Researchers Database

kikuchi motoshi

    Natural History Professor
Last Updated :2021/10/17

Researcher Information

URL

J-Global ID

Research Interests

  • behavior   細胞接着   解剖学   シグナル伝達   細胞・組織   Notchシグナリング   細胞分化   下垂体   濾胞星状細胞   ホルモン   糖鎖   組織学   細胞外マトリックス   

Research Areas

  • Life sciences / Biodiversity and systematics
  • Life sciences / Morphology, anatomy

Academic & Professional Experience

  • 2009/04 - Today  Jichi Medical UniversitySchool of Medicine教授
  • 2007/04 - 2009/03  Jichi Medical UniversitySchool of Medicine助教授
  • 2002/04 - 2007/03  Jichi Medical UniversitySchool of Medicine講師
  • 2000/10 - 2002/03  Jichi Medical UniversitySchool of Medicine助手
  • 1992/01 - 2000/09  Waseda University取扱主任
  • 1991/04 - 1991/12  日本学術振興会特別研究員PD

Education

  • 1988/04 - 1991/03  Waseda University  Graduate School of Science and Engineering

Association Memberships

  • International Federation of Comparative Endocrinology   Asia Oceania Society for Comparative Endocrinology   THE JAPAN SOCIETY FOR PITUITARY RESEARCH   日本神経内分泌学会   日本臨床内分泌病理学会   JAPAN SOCIETY FOR COMPARATIVE ENDOCRINOLOGY   The Japan Endocrine Society   THE JAPANESE ASSOCIATION OF ANATOMISTS   

Published Papers

  • Motoshi Kikuchi, Kenkichi Takase, Morisada Hayakawa, Hiroko Hayakawa, Shin-Ichi Tominaga, Tsukasa Ohmori
    Molecular brain 13 (1) 74 - 74 2020/05 [Refereed][Not invited]
     
    Psychoneuroimmunological studies have clearly demonstrated that both cellular and humoral immunity are related to major depression. Soluble ST2 is regarded as a key molecule regulating immune system as well as cell proliferation. Indeed, soluble ST2 is reported to reduce IL-33-induced IL-6 and TNF-α production in macrophages and IL-33-induced IL-5 and IL-13 production in type 2 innate lymphoid cells. Elevated serum concentrations of soluble ST2 have been reported in patients with neuropsychiatric disorders, suggesting pathophysiological roles of soluble ST2 in behavioral phenotypes. Nevertheless, the relation between soluble ST2 and depressive behavior remain to be uncovered. To complement this point, we performed broad behavioral phenotyping, utilizing transgenic mice with a high concentration of serum ST2 in the present study. Soluble ST2 overexpression mice (ST2 Tg mice) were generated on a C3H/HeJ background. ST2 Tg mice crossed onto the BALB/c genetic background were used. Before starting tests, each mouse was observed in a clean cage for a general health check and neurological screening tests. In Experiment I, comprehensive behavioral phenotyping was performed to reveal the role of soluble ST2 on sensorimotor functions, anxiety-like behaviors, depression-like behaviors, social behaviors, and learning and memory functions. In Experiment II, to confirm the role of soluble ST2 on depression-like behaviors, a depression test battery (two bottle choice test, forced swimming test, and tail suspension test) was applied. The general health check indicated good general health and normal gross appearance for ST2 Tg mice. Further, the neurological reflexes of all the mice were normal. We found that soluble ST2 overexpression resulted in decreased social interaction. Moreover, depression-like behaviors of ST2 Tg mice were observed in two well-established behavioral paradigms, the forced swimming test and the tail suspension test. Nevertheless, hedonic reaction to sucrose was observed in ST2 Tg mice similar to WT mice. These results suggest the depression in the ST2 Tg mice. In conclusion, through a series of experiments, we established the animal model for assessing role of soluble ST2 in neuropsychiatric disorders, and revealed the possible involvement of soluble ST2 in depressive behavior.
  • 淺田 義和, 前田 佳孝, 鈴木 義彦, 川平 洋, 菊地 元史
    医学教育 (一社)日本医学教育学会 51 (6) 685 - 689 0386-9644 2020 [Refereed]
     
    背景:近年、国内外において、脱出ゲーム(ER)を用いた教育実践が増加している。方法:医学部1年生に対し、既存知識の確認とチームでの協力性を学習させる目的でERを用いた授業を行った。70分の授業時間のうち45分をERに用いた。パズル的な謎に加え、BLSなどのタスクも含めた運用を行った。また、最終的な回答を複数用意した分岐の導入など、学生の意欲を高めるための方策を取り入れた。結果:授業の運営を通じて、謎やストーリーの作成にかかる負荷、当日の人員確保などの課題が明らかになった。考察:ERを用いた教育実践に関しては包括的な調査が少ない。事例の整理を通じ、効果的な実践方法の検討を重ねる必要がある。(著者抄録)
  • Morio Azuma, Takehiro Tsukada, Takeshi Inagaki, Fujianti Casmad, Depicha Jindatip, Alimuddin Tofrizal, Rita Maliza, Khongorzul Batchuluun, Rahimi Syaidah, Nobuhiko Ohno, Ken Fujiwara, Motoshi Kikuchi, Takashi Yashiro
    Acta histochemica et cytochemica 51 (5) 145 - 152 2018/10 [Refereed][Not invited]
     
    Laminin, a major basement membrane protein, comprises three subunit chains: α, β, and γ chains. Among these chains, only the laminin α chain is capable of signaling via laminin receptors. Although laminin isoforms containing the α5 chain were reported to be the first laminin produced during rat anterior pituitary gland development, the functions of these isoforms are unknown. We used immunohistochemical techniques to localize the laminin α5 chain and its specific receptor, basal cell adhesion molecule (BCAM), in fetal and adult pituitary gland. Laminin α5 chain immunoreactivity was observed in the basement membrane of the primordial adenohypophysis at embryonic days 12.5 to 19.5. Double immunostaining showed that BCAM was present and co-localized with the laminin α5 chain in the tissue. Quantitative analysis showed that the laminin α5 chain and BCAM were expressed in the anterior pituitary gland during postnatal development and in adulthood (postnatal day 60). In the adult gland, co-localization of the laminin α5 chain and BCAM was observed, and BCAM was detected in both the folliculo-stellate cells and endothelial cells. These results suggest that laminin α5 chain signaling via BCAM occurs in both the fetal adenohypophysis and adult anterior pituitary gland.
  • Mochizuki S, Miki H, Zhou R, Kido Y, Nishimura W, Kikuchi M, Noda Y
    Experimental cell research 370 (2) 601 - 612 0014-4827 2018/09 [Refereed][Not invited]
  • Alimuddin Tofrizal, Ken Fujiwara, Morio Azuma, Motoshi Kikuchi, Depicha Jindatip, Takashi Yashiro, Shozo Yamada
    MEDICAL MOLECULAR MORPHOLOGY 50 (3) 145 - 154 1860-1480 2017/09 [Refereed][Not invited]
     
    Extracellular matrix (ECM) is essential in tissue physiology and pathologic conditions such as tumorigenesis. It affects tumor cell behavior, proliferation, and metastasis. Pituitary adenomas differ in their clinical characteristics, including ECM deposition, and we recently reported that the characteristics of collagen-producing cells differed between control human anterior pituitary gland and pituitary adenomas. ECM deposition is not defined solely by production; degradation and maintenance are also important. Tissue inhibitors of metalloproteinases (TIMPs) help maintain ECM by inhibiting degradation caused by matrix metalloproteases. The present study attempted to characterize TIMP-expressing cells in the human anterior pituitary. Specimens of human pituitary adenomas and control pituitary were obtained during surgery, and in situ hybridization for TIMP1, TIMP2, TIMP3, and TIMP4, followed by immunohistochemistry, was used to characterize TIMP-expressing cells. TIMP expression exhibited a distinct pattern in the human anterior pituitary. Azan staining showed that fibrous matrix deposition varied among pituitary adenomas and that the area of fibrosis was associated with the number and number of types of TIMP3-expressing cells. These results suggest that TIMPs are important in the maintenance of ECM in human pituitary and that TIMP expressions are altered in fibrosis associated with pituitary adenoma.
  • Rita Maliza, Ken Fujiwara, Morio Azuma, Motoshi Kikuchi, Takashi Yashiro
    ENDOCRINE JOURNAL 64 (6) 633 - 638 0918-8959 2017/06 [Refereed][Not invited]
     
    Retinoic acid (RA) is converted from retinal by retinaldehyde dehydrogenases (RALDHs) and is an essential signaling molecule in embryonic and adult tissue. We previously reported that RALDH1 was produced in the rat anterior pituitary gland and hypothesized that RA was generated in the gland. Midkine (MK) is an RA-inducible growth factor, and MK production in the rat anterior pituitary gland was recently reported. However, the mechanism that regulates gene expression of MK in the pituitary gland has not been determined. To investigate regulation of MK production in the anterior pituitary gland, we analyzed changes in MK mRNA in cultured rat anterior pituitary cells. We identified MK expressing cells by double-staining with in situ hybridization and immunohistochemical techniques for RALDH1. MK mRNA was expressed in RALDH1-producing cells in the anterior pituitary gland. Using isolated anterior pituitary cells of rats, we examined the effect of RA on gene expression of MK. Quantitative real-time PCR revealed that 72 h exposure to a concentration of 10(-6) M of retinal and all-trans retinoic acid increased MK mRNA levels by about 2-fold. Moreover, the stimulatory effect of all-trans retinoic acid was mimicked by the RA receptor agonist Am80. This is the first report to show that RA is important in regulating MK expression in rat anterior pituitary gland.
  • Khongorzul Batchuluun, Morio Azuma, Takashi Yashiro, Motoshi Kikuchi
    CELL AND TISSUE RESEARCH 368 (1) 125 - 133 0302-766X 2017/04 [Refereed][Not invited]
     
    The rat anterior pituitary is composed of hormone-producing cells, non-hormone-producing cells (referred to as folliculostellate cells) and marginal layer cells. In the adult rat, progenitor cells of hormone-producing cells have recently been reported to be maintained within this non-hormone-producing cell population. In tissue, non-hormone-producing cells construct homophilic cell aggregates by the differential expression of the cell adhesion molecule E-cadherin. We have previously shown that Notch signaling, a known regulator of progenitor cells in a number of organs, is activated in the cell aggregates. We now investigate the relationship between Notch signaling and E-cadherin-mediated cell adhesion in the pituitary gland. Immunohistochemically, Notch signaling receptor Notch2 and the ligand Jagged1 were localized within E-cadherin-positive cells in the marginal cell layer and in the main part of the anterior lobe, whereas Notch1 was localized in E-cadherin-positive and -negative cells. Activation of Notch signaling within E-cadherin-positive cells was confirmed by immunostaining of the Notch target HES1. Notch2 and Jagged1 were always co-localized within the same cells suggesting that homologous cells have reciprocal effects in activating Notch signaling. When the E-cadherin function was inhibited by exposure to a monoclonal antibody (DECMA-1) in primary monolayer cell culture, the percentage of HES1-positive cells among Notch2-positive cells was less than half that of the control. The present results suggest that E-cadherin-mediated cell attachment is necessary for the activation of Notch signaling in the anterior pituitary gland but not for the expression of the Notch2 molecule.
  • Khongorzul Batchuluun, Morio Azuma, Ken Fujiwara, Takashi Yashiro, Motoshi Kikuchi
    ACTA HISTOCHEMICA ET CYTOCHEMICA 50 (2) 63 - 69 0044-5991 2017 [Refereed][Not invited]
     
    After publication of reports describing the presence of stem/progenitor cells among non-hormone-producing cells in the pituitary, the mechanism responsible for proliferation and differentiation generated considerable interest. Several studies have suggested that Notch signaling is involved. In the present study, we examined the histochemical relationship between Notch signaling molecules and the transcription factor SOX2 in rat pituitary. Combined in situ hybridization and immunohistochemistry showed that Notch2 mRNA and SOX2 were co-expressed at embryonic day 14.5 in most cells in the adenohypophyseal primordium. In adult rat pituitary, double immunohistochemistry showed that SOX2 and either Notch2 or the Notch signaling target HES1 were co-localized within cells with large oval nuclei in both the marginal cell layer and cell aggregates in the main part of the anterior lobe, which are believed to be stem cell niches. Furthermore, when the Notch signaling inhibitor DAPT was added to a primary culture of adult rat anterior pituitary cells, the proportion of SOX2-expressing cells within Notch2-positive cells was approximately 30% lower. These findings suggest that Notch signaling has a role in maintaining the stemness of precursor cells in the adult rat pituitary gland.
  • Rahimi Syaidah, Takehiro Tsukada, Morio Azuma, Kotaro Horiguchi, Ken Fujiwara, Motoshi Kikuchi, Takashi Yashiro
    Acta histochemica et cytochemica 49 (6) 171 - 179 0044-5991 2016/12 [Refereed][Not invited]
     
    Fibromodulin belongs to the family of small leucine-rich proteoglycans (SLRPs), an active component of extracellular matrix. It directly binds collagens to promote fibrillogenesis and also binds transforming growth factor-beta (TGFβ) to antagonize its actions. Our previous studies of rat anterior pituitary gland revealed that fibromodulin is expressed in folliculostellate cells and pericytes. Although our recent study showed that TGFβ2 secreted from folliculostellate cells induces collagen synthesis in pericytes, the involvement of fibromodulin in TGFβ2-mediated collagen regulation has not been studied. The present study examined the effect of TGFβ2 on fibromodulin synthesis in rat anterior pituitary gland. In situ hybridization for TGFβ receptor II and immunohistological techniques revealed the presence of TGFβ receptor II in folliculostellate cells and pericytes. To confirm canonical TGFβ intracellular signaling, Smad2 immunocytochemistry was performed. Nuclear translocation of Smad2 was observed in folliculostellate cells and pericytes after TGFβ2 treatment. TGFβ2 strongly enhanced fibromodulin mRNA and protein expressions, and TGFβ2-induced mRNA expression was completely blocked by TGFβ receptor I inhibitor (SB431542). These results suggest that folliculostellate cells and pericytes exhibit canonical TGFβ2 signaling, which is associated with fibromodulin production. Thus, this is the first report to show that TGFβ signaling regulates the endogenous TGFβ antagonist fibromodulin in the gland.
  • Rita Maliza, Ken Fujiwara, Takehiro Tsukada, Morio Azuma, Motoshi Kikuchi, Takashi Yashiro
    Endocrine journal 63 (6) 555 - 61 0918-8959 2016/06 [Refereed][Not invited]
     
    Retinoic acid (RA) is an important signaling molecule in embryonic development and adult tissue. The actions of RA are mediated by the nuclear receptors retinoic acid receptor (RAR) and retinoid X receptor (RXR), which regulate gene expression. RAR and RXR are widely expressed in the anterior pituitary gland. RA was reported to stimulate growth hormone (GH) gene expression in the anterior pituitary cells. However, current evidence is unclear on the role of RA in gene expression of growth hormone-releasing hormone receptor (Ghrh-r), growth hormone secretagogue receptor (Ghs-r) and somatostatin receptors (Sst-rs). Using isolated anterior pituitary cells of rats, we examined the effects of RA on gene expression of these receptors and GH release. Quantitative real-time PCR revealed that treatment with all-trans retinoic acid (ATRA; 10(-6) M) for 24 h increased gene expression levels of Ghrh-r and Ghs-r; however, expressions of Sst-r2 and Sst-r5 were unchanged. Combination treatment with the RAR-agonist Am80 and RXR-agonist PA024 mimicked the effects of ATRA on Ghrh-r and Ghs-r gene expressions. Exposure of isolated pituitary cells to ATRA had no effect on basal GH release. In contrast, ATRA increased growth hormone-releasing hormone (GHRH)- and ghrelin-stimulated GH release from cultured anterior pituitary cells. Our results suggest that expressions of Ghrh-r and Ghs-r are regulated by RA through the RAR-RXR receptor complex and that RA enhances the effects of GHRH and ghrelin on GH release from the anterior pituitary gland.
  • Takehiro Tsukada, Morio Azuma, Kotaro Horiguchi, Ken Fujiwara, Tom Kouki, Motoshi Kikuchi, Takashi Yashiro
    The Journal of endocrinology 229 (2) 159 - 70 0022-0795 2016/05 [Refereed][Not invited]
     
    The anterior pituitary gland comprises five types of endocrine cells plus non-endocrine cells including folliculostellate cells, endothelial cells, and capillary mural cells (pericytes). In addition to being controlled by the hypothalamic-pituitary-target organ axis, the functions of these cells are likely regulated by local cell and extracellular matrix (ECM) interactions. However, these complex interactions are not fully understood. We investigated folliculostellate cell-mediated cell-to-cell interaction. Using S100β-GFP transgenic rats, which express GFP in folliculostellate cells, we designed a three-dimensional cell culture to examine the effects of folliculostellate cells. Interestingly, removal of folliculostellate cells reduced collagen synthesis (Col1a1 and Col3a1). Because pericytes are important collagen-producing cells in the gland, we stained for desmin (a pericyte marker). Removal of folliculostellate cells resulted in fewer desmin-positive pericytes and less desmin mRNA. We then attempted to identify the factor mediating folliculostellate cell-pericyte interaction. RT-PCR and in situ hybridization revealed that the important profibrotic factor transforming growth factor beta-2 (TGFβ2) was specifically expressed in folliculostellate cells and that TGFβ receptor II was expressed in pericytes, endothelial cells, and parenchymal cells. Immunocytochemistry showed that TGFβ2 induced SMAD2 nuclear translocation in pericytes. TGFβ2 increased collagen synthesis in a dose-dependent manner. This action was completely blocked by TGFβ receptor I inhibitor (SB431542). Diminished collagen synthesis in folliculostellate cell-deficient cell aggregates was partially recovered by TGFβ2. TGFβ2-mediated folliculostellate cell-pericyte interaction appears to be essential for collagen synthesis in rat anterior pituitary. This finding sheds new light on local cell-ECM interactions in the gland.
  • Morio Azuma, Alimuddin Tofrizal, Rita Maliza, Khongorzul Batchuluun, Dini Ramadhani, Rahimi Syaidah, Takehiro Tsukada, Ken Fujiwara, Motoshi Kikuchi, Kotaro Horiguchi, Takashi Yashiro
    Acta histochemica et cytochemica 48 (6) 185 - 92 0044-5991 2015/12 [Refereed][Not invited]
     
    The extracellular matrix (ECM) is important in creating cellular environments in tissues. Recent studies have demonstrated that ECM components are localized in anterior pituitary cells and affect cell activity. Thus, clarifying the mechanism responsible for ECM maintenance would improve understanding of gland function. Tissue inhibitors of metalloproteinases (TIMPs) are endogenous inhibitors of matrix metalloproteinases and participate in ECM degradation. In this study, we investigated whether cells expressing TIMPs are present in rat anterior pituitary gland. Reverse transcription polymerase chain reaction was used to analyze expression of the TIMP family (TIMP1-4), and cells producing TIMPs in the gland were identified by using in situ hybridization. Expression of TIMP1, TIMP2, and TIMP3 mRNAs was detected, and the TIMP-expressing cells were located in the gland. The TIMP-expressing cells were also investigated by means of double-staining with in situ hybridization and immunohistochemical techniques. Double-staining revealed that TIMP1 mRNA was expressed in folliculostellate cells. TIMP2 mRNA was detected in folliculostellate cells, prolactin cells, and thyroid-stimulating hormone cells. TIMP3 mRNA was identified in endothelial cells, pericytes, novel desmin-immunopositive perivascular cells, and folliculostellate cells. These findings indicate that TIMP1-, TIMP2-, and TIMP3-expressing cells are present in rat anterior pituitary gland and that they are involved in maintaining ECM components.
  • Ken Fujiwara, Kotaro Horiguchi, Rita Maliza, Alimuddin Tofrizal, Khongorzul Batchuluun, Dini Ramadhani, Rahimi Syaidah, Takehiro Tsukada, Morio Azuma, Motoshi Kikuchi, Takashi Yashiro
    Cell and tissue research 359 (3) 909 - 14 0302-766X 2015/03 [Refereed][Not invited]
     
    Midkine (MK) belongs to a family of secreted heparin-binding growth factors and is highly expressed in various tissues during development. MK has multiple functions, such as regulation of cell proliferation, migration, survival and differentiation. We recently reported that MK mRNA is strongly expressed in the developing rat pituitary gland. In the adult pituitary, however, expression of MK and its receptor and the characteristics of the cells that produce them, have not been determined. Therefore, in this study, we investigate whether MK and its receptor, protein tyrosine phosphatase receptor-type Z (Ptprz1), are present in the adult rat pituitary. In situ hybridization, real-time reverse transcription-PCR and immunoblotting were performed to assess MK and Ptprz1 expression. We also characterize MK- and Ptprz1-expressing cells by double-staining with in situ hybridization and immunohistochemical techniques for each pituitary hormone or S100 protein [a marker of folliculostellate (FS) cells]. MK-expressing cells were located in the anterior and posterior lobes but not in the intermediate lobe. Double-staining and immunoblotting revealed that MK mRNA and protein were only expressed in FS cells in the anterior pituitary. Regarding Ptprz1 expression, Ptprz1 mRNA was detected in adrenocorticotropic hormone (ACTH) cells and growth hormone (GH) cells but not in prolactin cells, thyroid-stimulating hormone cells, luteinizing hormone cells, or FS cells. These findings suggest that MK produced in FS cells acts locally on ACTH cells and GH cells via Ptprz1 in the adult rat anterior pituitary.
  • Ken Fujiwara, Rita Maliza, Alimuddin Tofrizal, Khongorzul Batchuluun, Dini Ramadhani, Takehiro Tsukada, Morio Azuma, Kotaro Horiguchi, Motoshi Kikuchi, Takashi Yashiro
    Cell and tissue research 357 (1) 337 - 44 0302-766X 2014/07 [Refereed][Not invited]
     
    Pituitary gland development is controlled by numerous signaling molecules, which are produced in the oral ectoderm and diencephalon. A newly described family of heparin-binding growth factors, namely midkine (MK)/pleiotrophin (PTN), is involved in regulating the growth and differentiation of many tissues and organs. Using in situ hybridization with digoxigenin-labeled cRNA probes, we detected cells expressing MK and PTN in the developing rat pituitary gland. At embryonic day 12.5 (E12.5), MK expression was localized in Rathke's pouch (derived from the oral ectoderm) and in the neurohypophyseal bud (derived from the diencephalon). From E12.5 to E19.5, MK mRNA was expressed in the developing neurohypophysis, and expression gradually decreased in the developing adenohypophysis. To characterize MK-expressing cells, we performed double-staining of MK mRNA and anterior pituitary hormones. At E19.5, no MK-expressing cells were stained with any hormone. In contrast, PTN was expressed only in the neurohypophysis primordium during all embryonic stages. In situ hybridization clearly showed that MK was expressed in primitive (immature/undifferentiated) adenohypophyseal cells and neurohypophyseal cells, whereas PTN was expressed only in neurohypophyseal cells. Thus, MK and PTN might play roles as signaling molecules during pituitary development.
  • Dini Ramadhani, Takehiro Tsukada, Ken Fujiwara, Morio Azuma, Motoshi Kikuchi, Takashi Yashiro
    Acta histochemica et cytochemica 47 (5) 231 - 7 0044-5991 2014 [Refereed][Not invited]
     
    Cell-matrix interaction is required for tissue development. Laminin, a major constituent of the basement membrane, is important for structural support and as a ligand in tissue development. Laminin has 19 isoforms, which are determined by combinational assembly of five α, three β, and three γ chains (eg, laminin 121 is α1, β2, and γ1). However, no report has identified the laminin isoforms expressed during pituitary development. We used in situ hybridization to investigate all laminin chains expressed during rat anterior pituitary development. The α5 chain was expressed during early pituitary development (embryonic day 12.5-15.5). Expression of α1 and α4 chains was noted in vasculature cells at embryonic day 19.5, but later diminished. The α1 chain was re-expressed in parenchymal cells of anterior lobe from postnatal day 10 (P10), while the α4 chain was present in vasculature cells from P30. The α2 and α3 chains were transiently expressed in vasculature cells and anterior lobe, respectively, only at P30. Widespread distribution of β and γ chains was also observed during development. These findings suggest that numerous laminin isoforms are involved in anterior pituitary gland development and that alteration of the expression pattern is required for proper development of the gland.
  • Takehiro Tsukada, Ken Fujiwara, Kotaro Horiguchi, Morio Azuma, Dini Ramadhani, Alimuddin Tofrizal, Khongorzul Batchuluun, Rita Maliza, Rahimi Syaidah, Motoshi Kikuchi, Takashi Yashiro
    Acta histochemica et cytochemica 47 (5) 239 - 45 0044-5991 2014 [Refereed][Not invited]
     
    The anterior pituitary gland is organized tissue comprising hormone-producing cells and folliculostellate (FS) cells. FS cells interconnect to form a meshwork, and their cytoplasmic processes are anchored by a basement membrane containing laminin. Recently, we developed a three-dimensional (3D) cell culture that reproduces this FS cell architecture. In this study of the novel function of FS cells, we used transgenic rats that express green fluorescent protein in FS cells for the 3D culture. Anterior pituitary cells were cultured with different proportions of FS cells (0%, 5%, 10%, and 20%). Anterior pituitary cells containing 5-20% FS cells formed round/oval cell aggregates, whereas amorphous cell aggregates were formed in the absence of FS cells. Interestingly, immunohistochemistry showed laminin-immunopositive cells instead of extracellular laminin deposition in FS cell-deficient cell aggregates. Double-immunostaining revealed that these laminin-immunopositive cells were gonadotrophs. Laminin mRNA expression did not differ in relation to the presence or absence of FS cells. When anterior pituitary cells with no FS cells were cultured with FS cell-conditioned medium, the proportion of laminin-immunopositive cells was lower than in control. These results suggest that a humoral factor from FS cells is required for laminin release from gonadotrophs.
  • Rahimi Syaidah, Kotaro Horiguchi, Ken Fujiwara, Takehiro Tsukada, Motoshi Kikuchi, Takashi Yashiro
    Cell and tissue research 354 (2) 633 - 8 0302-766X 2013/11 [Refereed][Not invited]
     
    The anterior pituitary is a complex organ consisting of five types of hormone-producing cells, non–hormone-producing cells such as folliculostellate (FS) cells and vascular cells (endothelial cells and pericytes). We have previously shown that FS cells and pericytes produce fibromodulin, a small leucine-rich proteoglycan (SLRP). SLRPs are major proteoglycans of the extracellular matrix (ECM) and are important in regulating cell signaling pathways and ECM assembly. However, the mechanism regulating fibromodulin expression in the anterior pituitary has not been elucidated. Here, we investigate whether fibromodulin expression is modulated by major anterior pituitary ECM components such as laminin and type I collagen. Using transgenic rats expressing green fluorescent protein (GFP) specifically in FS cells, we examine fibromodulin expression in GFP-positive (FS cells) and GFP-negative cells (e.g., pericytes, endocrine cells and endothelial cells). Immunostaining and Western blot analysis were used to assess protein expression in the presence and absence of laminin or type I collagen. We confirmed fibromodulin expression in the pituitary and observed the up-regulation of fibromodulin in FS cells in the presence of ECM components. However, neither laminin nor type I collagen affected expression in GFP-negative cells. This suggests that laminin and type I collagen support the function of FS cells by increasing fibromodulin protein expression in the anterior pituitary.
  • Kotaro Horiguchi, Rahimi Syaidah, Ken Fujiwara, Takehiro Tsukada, Dini Ramadhani, Depicha Jindatip, Motoshi Kikuchi, Takashi Yashiro
    Cell and tissue research 353 (3) 473 - 81 0302-766X 2013/09 [Refereed][Not invited]
     
    In the anterior pituitary gland, folliculo-stellate cells and five types of hormone-producing cells are surrounded by an extracellular matrix (ECM) essential for these cells to perform their respective roles. Syndecans-type I transmembrane cell-surface heparan sulfate proteoglycans act as major ECM coreceptors via their respective heparan sulfate chains and efficiently transduce intracellular signals through the convergent action of their transmembrane and cytoplasmic domains. The syndecans comprise four family members in vertebrates: syndecan-1, -2, -3 and -4. However, whether syndecans are produced in the pituitary gland or whether they have a role as a coreceptor is not known. We therefore used (1) reverse transcription plus the polymerase chain reaction to analyze the expression of syndecan genes and (2) immunohistochemical techniques to identify the cells that produce the syndecans in the anterior pituitary gland of adult rat. Syndecan-2 mRNA expression was clearly detected in the corticotropes of the anterior pituitary gland. Moreover, the expression of syndecan-2 in the developing pituitary gland had a distinct temporospatial pattern. To identify the cells expressing syndecan-2 in the developing pituitary gland, we used double-immunohistochemistry for syndecan-2 and the cell markers E-cadherin (immature cells) and Ki-67 (proliferating cells). Some E-cadherin- and Ki-67-immunopositive cells expressed syndecan-2. Therefore, syndecan-2 expression occurs in developmentally regulated patterns and syndecan-2 probably has different roles in adult and developing anterior pituitary glands.
  • Takehiro Tsukada, Tom Kouki, Ken Fujiwara, Dini Ramadhani, Kotaro Horiguchi, Motoshi Kikuchi, Takashi Yashiro
    Acta histochemica et cytochemica 46 (4) 121 - 7 0044-5991 2013/08 [Refereed][Not invited]
     
    The anterior pituitary gland comprises 5 types of hormone-producing cells and non-endocrine cells, such as folliculostellate (FS) cells. The cells form a lobular structure surrounded by extracellular matrix (ECM) but are not randomly distributed in each lobule; hormone-producing cells have affinities for specific cell types (topographic affinity), and FS cells form a homotypic meshwork. To determine whether this cell and ECM organization can be reproduced in vitro, we developed a 3-dimensional (3D) model that utilizes hanging drop cell culture. We found that the topographic affinities of hormone-producing cells were indeed maintained (ie, GH to ACTH cells, GH to TSH cells, PRL to LH/FSH cells). Fine structures in hormone-producing cells retained their normal appearance. In addition, FS cells displayed well-developed cytoplasmic protrusions, which interconnected with adjacent FS cells to form a 3D meshwork. In addition, reassembly of gap junctions and pseudofollicles among FS cells was observed in cell aggregates. Major ECM components-collagens and laminin-were deposited and distributed around the cells. In sum, the dissociated anterior pituitary cells largely maintained their in vivo anterior pituitary architectures. This culture system appears to be a powerful experimental tool for detailed analysis of anterior pituitary cell organization.
  • Yukiko Tando, Ken Fujiwara, Takashi Yashiro, Motoshi Kikuchi
    CELL AND TISSUE RESEARCH 351 (3) 511 - 519 0302-766X 2013/03 [Refereed][Not invited]
     
    Notch signaling is a cell-to-cell signaling system involved in the maintenance of precursor cells in many tissues. Although Notch signaling has been reported in the pituitary gland, the histological characteristics of Notch receptors and ligands in the gland are unknown. Here, we report the histological gene expression pattern of Notch receptors and ligands and the role of Notch signaling in cellular proliferation in adult rat pituitary gland. In situ hybridization detected transcripts of Notch1 and 2 and Jagged1 and 2. Double-staining with a combination of in situ hybridization and immunohistochemistry revealed that their mRNAs were localized in almost half of the S100-protein-positive cells, which are generally regarded as marginal layer cells and folliculo-stellate cells. In primary culture of anterior pituitary cells, proliferation of S100-protein-positive cells was modulated by Notch signaling inhibitor and solubilized Notch ligand. Furthermore, quantitative analysis revealed that the inhibition of Notch signaling led to the down-regulation of mRNA for the Notch target gene Hes1 and the up-regulation of p57 gene expression. These findings suggest that Notch signaling is involved in the proliferation of S100-protein-positive cells, presumably precursor cells, in adult rat pituitary gland.
  • Kotaro Horiguchi, Rahimi Syaidah, Ken Fujiwara, Takehiro Tsukada, Dini Ramadhani, Depicha Jindatip, Motoshi Kikuchi, Takashi Yashiro
    Cell and tissue research 351 (1) 207 - 12 0302-766X 2013/01 [Refereed][Not invited]
     
    Proteoglycans are components of the extracellular matrix and comprise a specific core protein substituted with covalently linked glycosaminoglycan chains. Small leucine-rich proteoglycans (SLRPs) are a major family of proteoglycans and have key roles as potent effectors in cellular signaling pathways. Research during the last two decades has shown that SLRPs regulate biological functions in many tissues such as skin, tendon, kidney, liver, and heart. However, little is known of the expression of SLRPs, or the characteristics of the cells that produce them, in the anterior pituitary gland. Therefore, we have determined whether SLRPs are present in rat anterior pituitary gland. We have used real-time reverse transcription with the polymerase chain reaction to analyze the expression of SLRP genes and have identified the cells that produce SLRPs by using in situ hybridization with a digoxigenin-labeled cRNA probe. We have clearly detected the mRNA expression of SLRP genes, and cells expressing decorin, biglycan, fibromodulin, lumican, proline/arginine-rich end leucine-rich repeat protein (PRELP), and osteoglycin are located in the anterior pituitary gland. We have also investigated the possible double-staining of SLRP mRNA and pituitary hormones, S100 protein (a marker of folliculostellate cells), desmin (a marker of capillary pericytes), and isolectin B4 (a marker of endothelial cells). Decorin, biglycan, fibromodulin, lumican, PRELP, and osteoglycin mRNA have been identified in S100-protein-positive and desmin-positive cells. Thus, we conclude that folliculostellate cells and pericytes produce SLRPs in rat anterior pituitary gland.
  • Dini Ramadhani, Takehiro Tsukada, Ken Fujiwara, Kotaro Horiguchi, Motoshi Kikuchi, Takashi Yashiro
    Acta histochemica et cytochemica 45 (5) 309 - 15 0044-5991 2012/10 [Refereed][Not invited]
     
    Laminin is a key component of the basement membrane and is involved in the structural scaffold and in cell proliferation and differentiation. Research has identified 19 laminin isoforms, which are assemblies of α, β, and γ chains (eg, the α1, β1, and γ1 chains form the laminin 111 isoform). Although laminin is known to be present in the anterior pituitary, the specific laminin isoforms have not been identified. This study used molecular biological and histochemical techniques-namely, RT-PCR, immunohistochemistry, and in situ hybridization-to identify the laminin isoforms and laminin-producing cells in rat anterior pituitary. RT-PCR showed that laminin α1, α3, and α4 genes were expressed in anterior pituitary. Immunohistochemistry revealed laminin α1 in gonadotrophs and laminin α4 in almost all vascular endothelial cells. Laminin α3 was seen in a subset of vascular endothelial cells. We then performed in situ hybridization to localize β and γ chains in these cells and found that laminin β1, β2, and γ1 were expressed in gonadotrophs and that laminin β1 and γ1 were expressed in endothelial cells. In conclusion, we identified gonadotroph-type (laminin 111 and 121) and vascular-type (laminin 411 and 311) laminin isoforms in rat anterior pituitary.
  • Kotaro Horiguchi, Tom Kouki, Ken Fujiwara, Takehiro Tsukada, Floren Ly, Motoshi Kikuchi, Takashi Yashiro
    The Journal of endocrinology 214 (2) 199 - 206 0022-0795 2012/08 [Refereed][Not invited]
     
    Folliculostellate (FS) cells in the anterior pituitary gland appear to have multifunctional properties. FS cells connect to each other at gap junctions and thereby form a histological and functional network. We have performed a series of studies on network formation in FS cells and recently reported that FS cells markedly prolong their cytoplasmic processes and form numerous interconnections with neighboring FS cells in the presence of laminin, an extracellular matrix (ECM) component of the basement membrane. In this study, we investigated the mechanism of this extension of FS cell cytoplasmic processes under the influence of laminin and found that laminin promoted stress fiber formation within FS cells. Next, we noted that formation of stress fibers in FS cells was mediated by syndecan-4, a transmembrane proteoglycan that binds ECM and soluble factors via their extracellular glycosaminoglycan chain. We then observed that expressions of syndecan-4 and α-actinin (a microfilament bundling protein that cross-links actin stress fibers in FS cells) were upregulated by laminin. Using specific siRNA of syndecan-4, actin polymerization of FS cells was inhibited. Our findings suggest that FS cells received a signal from laminin-syndecan-4 interaction, which resulted in morphological changes, and that the formation of a morphological and functional network in FS cells was transduced by a syndecan-4-dependent mechanism in the presence of ECM.
  • Kotaro Horiguchi, Cimi Ilmiawati, Ken Fujiwara, Takehiro Tsukada, Motoshi Kikuchi, Takashi Yashiro
    Endocrinology 153 (4) 1717 - 24 0013-7227 2012/04 [Refereed][Not invited]
     
    The anterior pituitary gland is composed of five types of hormone-producing cells plus folliculostellate (FS) cells, which do not produce classical anterior pituitary hormones. FS cells are interconnected by cytoplasmic processes and encircle hormone-producing cells or aggregate homophilically. Using living-cell imaging of primary culture, we recently reported that some FS cells precisely extend their cytoplasmic processes toward other FS cells and form interconnections with them. These phenomena suggest the presence of a chemoattractant factor that facilitates the interconnection. In this study, we attempted to discover the factor that induces interconnection of FS cells and succeeded in identifying chemokine (CXC)-L12 and its receptor CXCR4 as potential candidate molecules. CXCL12 is a chemokine of the CXC subfamily. It exerts its effects via CXCR4, a G protein-coupled receptor. The CXCL12/CXCR4 axis is a potent chemoattractant for many types of neural cells. First, we revealed that CXCL12 and CXCR4 are expressed by FS cells in rat anterior pituitary gland. Next, to clarify the function of the CXCL12/CXCR4 axis in FS cells, we observed living anterior pituitary cells in primary culture with specific CXCL12 inhibitor or CXCR4 antagonist and noted that extension of cytoplasmic processes and interconnection of FS cells were inhibited. Finally, we examined FS cell migration and invasion by using Matrigel matrix assays. CXCL12 treatment resulted in markedly increased FS cell migration and invasion. These data suggest that FS cells express chemokine CXCL12 and its receptor CXCR4 and that the CXCL12/CXCR4 axis evokes interconnection of FS cells.
  • Changes in plasma gonadotrophins, 17β-oestradiol, progesterone, prolactin, thyroxine and triiodothyronine concentrations in female Japanese quail (Coturnix coturnix japonica) of a heavy body weight line during photo-induced ovarian growth and regression
    S J Henare, M Kikuchi, R T Talbot, J F Cockrem
    British Poultry Science 53 (4) 520 - 530 2012 [Refereed]
  • Changes in plasma gonadotrophins, testosterone, prolactin, thyroxine and triiodothyronine concentrations in male Japanese quail (Coturnix coturnix japonica) of a heavy body weight line during photo-induced testicular growth and regression
    S J Henare, M Kikuchi, R T Talbot, J F Cockrem
    British Poultry Science 52 (6) 782 - 791 2011/12 [Refereed]
  • Motoshi Kikuchi, Megumi Yatabe, Yukiko Tando, Takashi Yashiro
    CELL AND TISSUE RESEARCH 345 (3) 425 - 429 0302-766X 2011/09 [Refereed][Not invited]
     
    In the anterior and intermediate lobes of the rat pituitary gland, non-hormone-producing cells that express S-100 protein coexist with various types of hormone-producing cells and are believed to function as phagocytes, supporting and paracrine-controlling cells of hormone-producing cells and stem cells, among other functions; however, their cytological characteristics are not yet fully understood. Using a transgenic rat that expresses green fluorescent protein under the promoter of the S100 beta protein gene, we immunohistochemically detected expression of the luteinizing hormone, thyroid-stimulating hormone, prolactin, growth hormone and proopiomelanocortin by S-100 protein-positive cells located between clusters of hormone-producing cells in the intermediate lobe. These findings lend support to the hypothesis that S-100 protein-positive cells are capable of differentiating into hormone-producing cells in the adult rat pituitary gland.
  • Masahide Amemiya, Takashi Yashiro, Motoshi Kikuchi, Tom Kouki, Sueo Nakama, Yuichi Hoshino
    MEDICAL MOLECULAR MORPHOLOGY 44 (3) 139 - 145 1860-1480 2011/09 [Refereed][Not invited]
     
    Stroke-prone spontaneously hypertensive rats (SHRSP) are known to show necrosis of the femoral head with a frequency of about 50%. This rat has thus been used as an animal model for necrosis of the femoral head in many studies. In a detailed investigation of feeding vessel disorders that cause femoral head necrosis, we observed changes over time in the feeding vessels using scanning electron microscopy and transmission electron microscopy. In scanning electron microscopy of vascular casts, abnormal findings in feeding vessels of SHRSP with aging from the immature stage included contortion and bending in the lumen with overall narrowing. Under transmission electron microscopy, decreased numbers of smooth muscle cells and increased amounts of collagen fibers were marked, and these changes with hypertrophy of vascular walls might be similar to those of arteriolosclerosis. The structural changes first revealed by transmission electron microscopic observation might cause the friability of the feeding vessels so that contortion and bending occurred, suggesting transient obstruction of blood flow to the femoral head and subsequent induction of femoral head necrosis. These findings should help in understanding the causes of femoral head necrosis in humans, including Perthes' disease.
  • Kotaro Horiguchi, Ken Fujiwara, Cimi Ilmiawati, Motoshi Kikuchi, Takehiro Tsukada, Tom Kouki, Takashi Yashiro
    The Journal of endocrinology 210 (1) 29 - 36 0022-0795 2011/07 [Refereed][Not invited]
     
    Folliculostellate (FS) cells in the anterior pituitary gland are believed to have multifunctional properties. Using transgenic rats that express green fluorescent protein (GFP) specifically in FS cells in the anterior pituitary gland (S100b-GFP rats), we recently revealed that FS cells in primary culture exhibited marked proliferation in the presence of laminin, an extracellular matrix (ECM) component of the basement membrane. In a process referred to as matricrine action, FS cells receive ECM as a signal through their receptors, which results in morphological and functional changes. In this study, we investigated matricrine signaling in FS cells and observed that the proliferation of FS cells is mediated by integrin β1, which is involved in various signaling pathways for cell migration and proliferation in response to ECM. Then, we analyzed downstream events of the integrin β1 signaling pathway in the proliferation of FS cells and identified caveolin 3 as a potential candidate molecule. Caveolin 3 is a membrane protein that binds cholesterol and a number of signaling molecules that interact with integrin β1. Using specific small interfering RNA of caveolin 3, the proliferation of FS cells was inhibited. Furthermore, caveolin 3 drove activation of the mitogen-activated protein kinase (MAPK) signaling cascades, which resulted in upregulation of cyclin D1 in FS cells. These findings suggest that matricrine signaling in the proliferation of FS cells was transduced by a caveolin 3-mediated integrin β1 signaling pathway and subsequent activation of the MAPK pathway.
  • Kotaro Horiguchi, Tom Kouki, Ken Fujiwara, Motoshi Kikuchi, Takashi Yashiro
    JOURNAL OF ENDOCRINOLOGY 208 (3) 225 - 232 0022-0795 2011/03 [Refereed][Not invited]
     
    Folliculo-stellate (FS) cells in the anterior pituitary gland are believed to have multifunctional properties. FS cells connect to each other not only by mechanical means, but also by gap junctional cell-to-cell communication. Using transgenic rats that express green fluorescent protein (GFP) specifically in FS cells in the anterior pituitary gland (S100b-GFP rats), we recently revealed that FS cells in primary culture markedly change their shape, and form numerous interconnections with neighboring FS cells in the presence of laminin, an extracellular matrix (ECM) component of the basement membrane. Morphological and functional changes in cells are believed to be partly modified by matricrine signaling, by which ECM components function as cellular signals. In the present study, we examined whether gap junction formation between FS cells is affected by matricrine cues. A cell sorter was used to isolate FS cells from male S100b-GFP rat anterior pituitary for primary culture. We observed that mRNA and protein levels of connexin 43 in gap junction channels were clearly higher in the presence of laminin. In addition, we confirmed the formation of gap junctions between FS cells in primary culture by electron microscopy. Interestingly, we also observed that FS cells in the presence of laminin displayed well-developed rough endoplasmic reticulum and Golgi apparatus. Our findings suggest that, in anterior pituitary gland, FS cells may facilitate functional roles such as gap junctional cell-to-cell communication by matricrine signaling. Journal of Endocrinology (2011) 208, 225-232
  • Motoshi Kikuchi, Kenji Kusumoto, Ken Fujiwara, Kozue Takahashi, Yukiko Tando, Takashi Yashiro
    ACTA HISTOCHEMICA ET CYTOCHEMICA 44 (4) 159 - 164 0044-5991 2011 [Refereed][Not invited]
     
    Anterior pituitary glands contain five types of hormone-producing cells. Distinguishing and isolating specific types of living cells are essential for studying their function. Although many such attempts have been made, the results have been disappointing. In the present study, we labeled specific types of living hormone-producing cells by using potential differences in sugar chains on the cell surfaces. Cytochemical analysis with lectins and cholera toxin B subunit revealed that PNA, S-WGA, and cholera toxin B subunit recognized sugar chains specific to prolactin cells, ACTH cells, and GH cells, respectively, and that UEA-I recognized most of prolactin cells and GH cells. Next, fluorescence-activated cell sorting was used to isolate GH cells labeled by fluoresceinated cholera toxin B. The purity of the GH cell fraction estimated by immunocytochemistry and quantitative real-time PCR for cell type-specific genes was more than 98%, which was higher than that reported in earlier studies, including those using transgenic animals. We conclude that cytochemistry with lectins and cholera toxin B subunit is a straightforward, acceptable method of isolating specific types of anterior pituitary cells and that the cells isolated by this method can serve as useful materials in the study of anterior pituitary cells.
  • Ken Fujiwara, Depicha Jindatip, Motoshi Kikuchi, Takashi Yashiro
    CELL AND TISSUE RESEARCH 342 (3) 491 - 495 0302-766X 2010/12 [Refereed][Not invited]
     
    Type I and III collagens widely occur in the rat anterior pituitary gland and are the main components of the extracellular matrix (ECM). Although ECM components possibly play an important role in the function of the anterior pituitary gland, little is known about collagen-producing cells. Type I collagen is a heterotrimer of two alpha 1(I) chains (the product of the col1a1 gene) and one alpha 2(I) chain (the product of the col1a2 gene). Type III collagen is a homotrimer of alpha 1(III) chains (the product of the col3a1 gene). We used in situ hybridization with digoxigenin-labeled cRNA probes to examine the expression of col1a1, col1a2, and col3a1 mRNAs in the pituitary gland of adult rats. mRNA expression for these collagen genes was clearly observed, and cells expressing col1a1, col1a2, and col3a1 mRNA were located around capillaries in the gland. We also investigated the possible double-staining of collagen mRNA and pituitary hormones, S-100 protein (a marker of folliculo-stellate cells), or desmin (a marker of pericytes). Col1a1 and col3a1 mRNA were identified in desmin-immunopositive cells. Thus, only pericytes produce type I and III collagens in the rat anterior pituitary gland.
  • Kotaro Horiguchi, Motoshi Kikuchi, Kenji Kusumoto, Ken Fujiwara, Tom Kouki, Kotaro Kawanishi, Takashi Yashiro
    JOURNAL OF ENDOCRINOLOGY 204 (2) 115 - 123 0022-0795 2010/02 [Refereed][Not invited]
     
    Folliculo-stellate (FS) cells in the anterior pituitary gland appear to possess multifunctional properties. Recently, the development of transgenic rats (S100b-green fluorescent protein (GFP) rats) that express GFP specifically in FS cells in the anterior pituitary gland has allowed us to distinguish and observe living FS cells in other kinds of pituitary cells. We used S100b-GFP rats to investigate the topographic affinity of FS cells for other pituitary cells. We observed living FS cells in enzymatically dispersed anterior pituitary cells of S100b-GFP rats under a fluorescent microscope, and noted that FS cells markedly extended and contracted cytoplasmic processes and formed interconnections with neighboring FS cells. In addition, FS cells adhered to small clusters of GFP-negative cells, which were primarily hormone-producing cells, and these clusters further aggregated during the course of cytoplasmic contraction. In the presence of laminin, fibronectin, and varying types of collagen, FS cells showed marked changes in shape and specific proliferative activity; however, GFP-negative cells did not. On reverse transcription-PCR analysis and immunohistochemistry, FS cells were shown to express integrin subunits, which are the cell surface receptors for extracellular matrix (ECM). In the anterior pituitary gland, FS cells and the various types of hormone-producing cells generate a unique topography in the presence of basement membrane components and interstitial collagens. The novel characteristics of FS cells observed in the present study suggest that in the anterior pituitary gland, FS cells play important roles in determining and/or maintaining local cellular arrangement in the presence of ECM components. Journal of Endocrinology (2010) 204, 115-123
  • Kenji Kusumoto, Motoshi Kikuchi, Ken Fujiwara, Kotaro Horiguchi, Tom Kouki, Kotaro Kawanishi, Takashi Yashiro
    ACTA HISTOCHEMICA ET CYTOCHEMICA 43 (2) 83 - 88 0044-5991 2010 [Refereed][Not invited]
     
    Cadherins are a family of transmembrane glycoproteins that mediate cell-to-cell adhesion. A change in cadherin type in cells, i.e., cadherin switching, induces changes in the character of the cell. Recent studies of the developing rat adenohypophysis found that primordial cells co-expressed E- and N-cadherins, but that hormone-producing cells lost E- cadherin and ultimately possessed only N-cadherin. In the present study, we examined the roles of cadherin switching in cytogenesis of anterior pituitary cells by observing prolactin mRNA and protein expression in lactotrophs that were transformed with an E- cadherin expression vector. In hormone-producing cells that were transfected with a pIRES2-ZsGreen1 plasmid with a full-length E- cadherin cDNA (rE-cad-IZ) insert in primary culture, we detected E- and N-cadherins on plasma membrane and E- cadherin in cytoplasm. In these rE-cad-IZ-transfected cells, in situ hybridization revealed prolactin mRNA signals that were at a level identical to that in control cells, while prolactin protein was barely detectable using immunocytochemistry. The mean signal intensity of prolactin protein in rE-cad-IZ-transfected cells was approximately one fourth that in intact cells and in null-IZ-transfected cells (P<0.01). These results suggest that the expression of E-cadherin does not affect prolactin mRNA transcription; rather, it reduces prolactin protein content, presumably by affecting trafficking of secretory granules.
  • Ken Fujiwara, Motoshi Kikuchi, Kotaro Horiguchi, Kenji Kusumoto, Tom Kouki, Kotaro Kawanishi, Takashi Yashiro
    ENDOCRINE JOURNAL 56 (8) 963 - 973 0918-8959 2009/11 [Refereed][Not invited]
     
    Retinoic acid (RA) plays a critical role in embryonic development, growth, and reproduction. RA is synthesized from retinoids via oxidation processes, and the oxidation of retinal to RA is catalyzed by the retinaldehyde dehydrogenases (RALDHs). We previously reported that RALDH1 mRNA was expressed in the anterior pituitary glands of adult rats and suppressed by administration of 17 beta-estradiol in vivo. However, little is known about the mechanism regulating pituitary RALDH1 expression. In order to characterize the mechanism of estrogen-induced RALDH1 reduction, we examined the effect of 17 beta-estradiol on the regulation of pituitary RALDH1 gene expression and protein production both in vivo and in vitro. Using quantitative real-time PCR and immunoblot analysis, we found that levels of RALDH1 gene expression and protein production markedly decreased after 1-week treatment with 17 beta-estradiol in male rats. In immunohistochemical analysis, RALDH1-immunoreaction was observed in prolactin cells and folliculo-stellate cells. In 17 beta-estradiol-treated rats, RALDH1-immunoreactivity was lower in prolactin cells, but not in folliculo-stellate cells. Treatment of isolated anterior pituitary cells with 17 beta-estradiol (10(-14) - 10(-8) M) decreased expression of RALDH1 mRNA in a dose-dependent manner. Estradiol-induced suppression of RALDH1 expression was completely blocked by the estrogen receptor (ER) antagonist ICT 182, 780. The ER alpha-selective agonist propylpyrazole triol (10(-8) M) mimicked the effect of 17 beta-estradiol on RALDH1 expression, but the ER beta-selective agonist diarylpropionitrile (10(-8) M) did not. These results strongly suggest that RALDH1 mRNA expression is suppressed by 17 beta-estradiol through ER alpha, and that estrogen regulates the expression of RALDH1 and production of RA in the anterior pituitary gland.
  • Motoshi Kikuchi, Megumi Yatabe, Ken Fujiwara, Kotaro Horiguchi, Kenji Kusumoto, Tom Kouki, Atsushi Sakamoto, Takashi Yashiro
    ANATOMICAL SCIENCE INTERNATIONAL 84 (3) 155 - 160 1447-6959 2009/09 [Refereed][Not invited]
     
    Cadherins are a family of transmembrane glycoproteins that mediate cell-to-cell adhesion in solid tissues and have been reported to regulate not only morphogenesis but also cell motility, proliferation, and function by activating intracellular signaling pathways. We recently found that primordial cells in the developing rat adenohypophysis co-expressed E- and N-cadherins, but endocrine cells lost E-cadherin to possess only N-cadherin at certain embryonic stages. In the present study, we aimed to elucidate the temporal relationships between cadherin expression and cell proliferation as well as between cadherin expression and the onset of hormone production in embryonic adenohypophyses. Adenohypophyses and their primordia from embryonic and postnatal rats were fixed in Bouin's fluid and paraffin sections were routinely prepared. Multiple fluorescence immunohistochemistry was performed for combinations of E-cadherin, N-cadherin, proliferating cell nuclear antigen (a marker of proliferating cells), cyclin D1, and pituitary hormones. In primordia from embryonic days 13 through 16, proliferative activities were seen in cells that co-expressed E- and N-cadherin. Cells arrested proliferation coincidentally when they lost E-cadherin after embryonic day 16. Possession of E-cadherin was closely related with expression of cyclin D1 at this stage. Moreover, hormone production was observed from embryonic day 16 only in cells that lost E-cadherin. In the developing adenohypophysis, proliferation and differentiation of hormone-producing cells have been reported to be regulated by a variety of external humoral factors. Our results raise the possibility that changes in cadherins are closely involved in these processes.
  • Teruaki Endo, Takashi Ajiki, Hirokazu Inoue, Motoshi Kikuchi, Takashi Yashiro, Sueo Nakama, Yuichi Hoshino, Takashi Murakami, Eiji Kobayashi
    BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS 381 (3) 339 - 344 0006-291X 2009/04 [Refereed][Not invited]
     
    Rehabilitation is important for the functional recovery of patients with spinal cord injury. However, neurological events associated with rehabilitation remain unclear, Herein, we investigated neuronal regeneration and exercise following spinal cord injury, and found that assisted stepping exercise of spinal cord injured rats in the inflammatory phase causes allodynia, Sprague-Dawley rats with thoracic spinal cord contusion injury were Subjected to assisted stepping exercise 7 clays following injury. Exercise promoted microscopic recovery of corticospinal tract neurons, but the paw withdrawal threshold decreased and C fibers had aberrantly sprouted, suggesting a potential cause of the allodynia. Tropomyosin-related kinase B (TrkB) receptor for brain-derived neurotrophic factor (BDNF) was expressed on aberrantly sprouted C-fibers. Blocking of BDNF-TrkB signaling markedly suppressed aberrant sprouting and decreased the paw withdrawal threshold. Thus, early rehabilitation for spinal cord injury may cause allodynia with aberrant Sprouting of C-fibers through BDNF-TrkB signaling. (C) 2009 Elsevier Inc. All rights reserved.
  • Kotaro Horiguchi, Ken Fujiwara, Tom Kouki, Motoshi Kikuchi, Takashi Yashiro
    ANATOMICAL SCIENCE INTERNATIONAL 83 (4) 256 - 260 1447-6959 2008/12 [Refereed][Not invited]
     
    Folliculo-stellate (FS) cells in the anterior pituitary gland have been speculated to possess multifunctional properties. Because gap junctions (GJ) have been identified between FS cells, FS cells may be interconnected electrophysiologically by GJ and serve as signal transmission networks to modulate hormone release in the anterior pituitary gland. But whether GJ are localized among FS cells from the pars tuberalis through the pars distalis is unclear. The S100b-GFP transgenic rat has recently been generated, which expresses green fluorescent protein (GFP) specifically in FS cells in the anterior pituitary. This model is expected to be a powerful tool for studies of FS cells. The purpose of the present paper was therefore to examine the localization of GJ on connexin 43 immunohistochemistry throughout the anterior pituitary gland of S100b-GFP rats under confocal laser microscopy. The localization patterns of FS cells was also observed in primary culture of anterior pituitary cells and the question of whether GJ between FS cells are reconstructed in vitro was investigated. In vivo studies showed that GJ were present specifically between FS cells from the pars tuberalis to the pars distalis in the anterior pituitary gland. The appearance of FS cells was distinguished into two types, with localization of GJ differing between types. In vitro, it was observed for the first time that FS cells in primary culture could be categorized into two types. In vivo localization of GJ between FS cells was reconstructed in vitro. These morphological observations are consistent with the hypothesis that FS cells form an electrophysiological network throughout the anterior pituitary for signal transmission.
  • Ken Fujiwara, Bulgan Davaadash, Megumi Yatabe, Motoshi Kikuchi, Kotaro Horiguchi, Kenji Kusumoto, Tom Kouki, Takashi Yashiro
    MEDICAL MOLECULAR MORPHOLOGY 41 (3) 126 - 131 1860-1480 2008/09 [Refereed][Not invited]
     
    Retinoic acid (RA) plays a critical role in normal development and tissue maintenance and is also a regulatory factor of anterior pituitary cells. We previously demonstrated that a retinoic acid-synthesizing enzyme, retinaldehyde dehydrogenase 1 (RALDH1), is expressed in prolactin cells of adult rats and that estrogen suppressed RALDH1 expression. It is suggested that RA plays a role as a paracrine and/or autocrine signaling molecule in the anterior pituitary gland. However, the presence of RALDH1 in pituitary tumors has not been demonstrated. In this study, we examined the expression of RALDH1 in diethylstilbestrol-induced prolactinoma of LEXF RI rats. Quantitative analysis of mRNA levels by real-time PCR demonstrated drastic reduction of RALDH1 expression in the prolactinoma. We have also detected both mRNA expression and production by in situ hybridization and immunohistochemistry. Both mRNA-expressing cells and immunopositive cells remarkably decreased after 4 weeks of treatment with diethylstilbestrol. Fluorescence double immunohistochemistry of RALDH1 and prolactin revealed that prolactin-immunopositive cells do not colocalize with RALDH1 in the prolactinoma. These results suggest that the reduction of local RA generation relates to cell proliferation and tumorigenesis of lactotrophs.
  • Yoshio Mabuchi, Nobuyuki Shirasawa, Eisuke Sakuma, Ikuo Wada, Osamu Horiuchi, Motoshi Kikuchi, Atsushi Sakamoto, Damon C. Herbert, Tsuyoshi Soji
    TISSUE & CELL 40 (3) 157 - 166 0040-8166 2008/06 [Refereed][Not invited]
     
    Since [Westlud, K.N., Chils, G.V., 1982. Localization of serotonin fibers in the rat adenohypophysis. Endocrinology 111, 1761-1763] initially identified the serotonin nerve fibers in the anterior pituitary gland, attention has been paid to the rostral zone of the anterior lobe into which nerve fibers enter and subsequently spread to deeper regions of the lobe. The rostral zone is the trifurcated junction of the partes tuberalis, intermedia and distalis, and has the important role(s) for hormone secretion via the "transitional zone" [Sato, G, Shirasawa, N, Sakuma, E, Sato, Y, Asai, Y, Wada, I, Horiuchi, O, Sakamoto, A, Herbert, DC, Soji, T, 2005a. Intercellular communications within the rat anterior pituitary. XI: An immunohistochemical study of distributions of S-100 positive cells in the anterior pituitary of the rat. Tissue and Cell 37, 269-280.]. The objective of this study was to focus on the ultrastructure of this "zone." All of the animals studied were fixed by perfusion with glutaraldehyde via the left ventricle of the heart and examined by electron microscopy. In the "transitional zone," a cluster of neuronal elements was observed between the folliculo-stellate cell-rich area and the anterior lobe. This cluster consisted of myelinated fibers, unmyelinated fibers, neuroendocrine fibers, large cells, and supporting cells. The large cells were perikarya of neurons which made a "ganglion-like" structure with associated satellite cells. Agranular, folliculo-stellate cells were intermingled among the elements. This is the first report that neuronal elements form clusters in the "transitional zone." A relationship of the unmyetinated and neuroendocrine fibers in the basal layer and in the "transitional zone" is discussed. (C) 2007 Elsevier Ltd. All rights reserved.
  • Shu Takigami, Ken Fujiwara, Motoshi Kikuchi, Takashi Yashiro
    CELL AND TISSUE RESEARCH 331 (3) 589 - 594 0302-766X 2008/03 [Refereed][Not invited]
     
    In the anterior pituitary gland, c-Fos expression is evoked by various stimuli. However, whether c-Fos expression is directly related to the stimulation of anterior pituitary cells by hypothalamic secretagogues is unclear. To confirm whether the reception of hormone-releasing stimuli evokes c-Fos expression in anterior pituitary cells, we have examined c-Fos expression of anterior pituitary glands in rats administered with synthetic corticotrophin-releasing hormone (CRH) intravenously or subjected to restraint stress. Single intravenous administration of CRH increases the number of c-Fos-expressing cells, and this number does not change even if the dose is increased. Double-immunostaining has revealed that most of the c-Fos-expressing cells contain adrenocorticotrophic hormone (ACTH); corticotrophs that do not express c-Fos in response to CRH have also been found. However, restraint stress evokes c-Fos expression in most of the corticotrophs and in a partial population of lactotrophs. These results suggest that c-Fos expression increases in corticotrophs stimulated by ACTH secretagogues, including CRH. Furthermore, we have found restricted numbers of corticotrophs expressing c-Fos in response to CRH. Although the mechanism underlying the different responses to CRH is not apparent, c-Fos is probably a useful immunohistochemical marker for corticotrophs stimulated by ACTH secretagogues.
  • R Tsuru, H Kondo, Y Hojo, M Gama, O Mizuno, T Katsuki, K Shimada, M Kikuchi, T Yashiro
    Heart 94 (3) 305 - 310 1355-6037 2008/03 [Refereed]
  • Ken Fujiwara, Bulgan Davaadash, Motoshi Kikuchi, Shu Takigami, Takashi Yashiro
    Endocrine Journal 55 (1) 91 - 96 0918-8959 2008 [Refereed][Not invited]
     
    Retinoic acid (RA) plays a critical role in cell growth and tissue development. RA is also a regulating factor of pituitary function. RA is synthesized from retinoids through oxidation processes. The oxidation of retinal to RA is catalyzed by the retinaldehyde dehydrogenases (RALDHs), including RALDH1, RALDH2 and RALDH3. Recently, we demonstrated that RALDH1 is expressed in the anterior pituitary glands of adult male rats. However, the expression of RALDH1 in the female pituitary gland and the regulation of RALDH1 expression have not been determined. Therefore, we examined the expression of RALDH1 mRNA in the pituitary glands of adult female rats. By in situ hybridization with digoxigenin-labeled cRNA probes and quantitative real-time PCR analysis, we found that the expression level of RALDH1 was significantly lower in estrus as compared to proestrus, metestrus and diestrus. RALDH1 mRNA levels increased after ovariectomy and decreased remarkably after a 1-week treatment with 17β-estradiol implants. Estradiol (0.01-100 μg per rat) dose-dependently decreased the expression of RALDH1 in the pituitary glands after 24 hours of subcutaneous administration. These results clearly show that RALDH1 mRNA expression is suppressed by estrogen. We speculate that the generation of RA is regulated by estrogen and that RA plays a role in the estrus cycle through paracrine and/or autocrine mechanisms in the anterior pituitary gland of female rats.
  • Atsushi Sakamoto, Kazumoto Murata, Hideto Suzuki, Megumi Yatabe, Motoshi Kikuchi
    ACTA HISTOCHEMICA ET CYTOCHEMICA 41 (5) 143 - 147 0044-5991 2008 [Refereed][Not invited]
     
    Cadherins are a family of transmembrane glycoproteins that mediate cell-to-cell adhesion. Isoforms, including E- and N-cadherin, have been identified and shown to regulate morphogenesis through homophilic binding. In the ontogeny, the expressions of E- and N-cadherin change spatiotemporally, and the changes in cadherin isoforms, called cadherin switching, impact the mechanical adhesion of cells. Furthermore, cadherin functions as a receptor that transfers information from outside to inside cells, and in terms of switching, it affects cell phenotypes. To observe the expression patterns of E- and N-cadherins during embryogenesis and to identify cells that transiently coexpress both cadherins, we employed a recently developed immunohistochemical double staining technique in rat fetuses. At embryonic day 9, embryonic ectodermal cells more dominantly expressed E- cadherin, while mesodermal cells more dominantly expressed N-cadherin. At embryonic day 10, the expression pattern of E- cadherin in the surface ectoderm and endoderm and that of N-cadherin in the neuroectoderm were established. After embryonic day 10, unique co-expression of E-and N-cadherin was observed in primordia, such as the bulbus cordis, otic pit, notochord, and Rathke's pouch. In the present study, it was possible to visualize the expression patterns of E- and N-cadherin during early fetal development, which enabled us to morphologically clarify cadherin switching.
  • Ken Fujiwara, Motoshi Kikuchi, Shu Takigami, Tom Kouki, Takashi Yashiro
    CELL AND TISSUE RESEARCH 329 (2) 321 - 327 0302-766X 2007/08 [Refereed][Not invited]
     
    Retinoic acid (RA) plays a critical role in cell growth and tissue development and is also a regulatory factor of pituitary function. However, whether RA is generated in the pituitary gland and plays a role as a paracrine and/or autocrine factor is generally unknown. RA is synthesized from retinoids through oxidation processes. Dehydrogenases that catalyze the oxidation of retinal to RA are members of the retinaldehyde dehydrogenase (RALDH) family. Recently, we demonstrated that RALDH2 and RALDH3, but not RALDH1, were expressed in the developing anterior pituitary gland of rats, but the expression of RALDHs in the adult pituitary gland was not determined. Therefore, we have now examined the expression of RALDH1, RALDH2, and RALDH3 mRNAs in the pituitary gland of adult rats. Analysis by quantitative real-time polymerase chain reaction of adult pituitary glands has revealed a high level of RALDH1 mRNA but not of RALDH2 mRNA or RALDH3 mRNA. We have also detected mRNA expression for RALDH1 in the anterior pituitary gland by in situ hybridization with digoxigenin-labeled cRNA probes. Double-staining for RALDH1 mRNA and pituitary hormones or S-100 protein, a marker of folliculo-stellate cells (FS-cells), has revealed RALDH1 mRNA expression in a portion of prolactin-producing cells, marginal layer cells, and FS-cells. Our results suggest that RA is generated in the adult anterior pituitary gland, and that it may act locally on pituitary cells.
  • Motoshi Kikuchi, Miegumi Yatabe, Tom Kouki, Ken Fujiwara, Shu Takigami, Atsushi Sakamoto, Takashi Yashiro
    ANATOMICAL RECORD-ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY 290 (5) 486 - 490 1932-8486 2007/05 [Refereed][Not invited]
     
    Recently, we showed that hormone-producing cells express N-cadherin, while folliculo-stellate cells and marginal layer cells express E-cadherin in the adult rat anterior pituitary gland. These cells are believed to originate from a single cell population of the adenohypophyseal placode. In the present study, we immunohistochemically examined the divergence of cadherin types during pituitary histogenesis. Pituitary glands were excised from rats of embryonic day 11 (E11) through postnatal day 60 (P60) and paraffin sections were prepared. E- and N-cadherins were immunostained sequentially using monoclonal and polyclonal primary antibodies and fluorescent secondary antibodies. At E11, E-cadherin was expressed over oral epithelium, while N-cadherin expression was limited to the primordium of Rathke's pouch. When Rathke's pouch was formed at E13, E- and N-cadherin were broadly expressed in the entire cell population. N-cadherin was expressed particularly intensely in the layer of cells that faced the lumen. From E14 through E16, the majority of cells expressed both types of cadherins; however, the cell population to become the pars tuberalis expressed N-cadherin but not E-cadherin. From E18 through E20, when many hormone-producing cells appear, the number of cells that expressed N-cadherin alone increased. However, some cell populations in the pars distalis and multilayered marginal cells still expressed both cadherins. After birth, most of the cells came to express only one of the cadherin types. These results may suggest that undetermined adenohypophyseal cells express both E- and N-cadherin, but come to express either E- or N-cadherin during cytogenesis.
  • Ken Fujiwara, Fumihiko Maekawa, Motoshi Kikuchi, Shu Takigami, Toshihiko Yada, Takashi Yashiro
    CELL AND TISSUE RESEARCH 328 (1) 129 - 135 0302-766X 2007/04 [Refereed][Not invited]
     
    Retinoic acid (RA) plays an important role in cell growth and tissue development and is also a regulating factor of pituitary function. However, whether RA is generated in the pituitary gland and plays a role as a paracrine and/or autocrine hormone is generally unknown. RA is synthesized from retinoids through oxidation processes. Dehydrogenases catalyzing the oxidation of retinal to RA are members of the retinaldehyde dehydrogenase (RALDH) family. In this study, we examined the expression of RALDH1, RALDH2, and RALDH3 mRNA in the rat embryonic pituitary gland. By in situ hybridization with digoxigenin-labeled cRNA probes, we detected mRNA expression for RALDH2 and RALDH3, but not RALDH1. The expression of RALDH2 and RALDH3 was located in Rathke's pouch at embryonic day 12.5 (E12.5) and subsequently in the developing anterior pituitary gland. We also used quantitative real- time polymerase chain reaction to analyze RALDH2 and RALDH3 mRNA expression levels during the development of the pituitary gland. We found that pituitary RALDH2 and RALDH3 mRNA levels were high at E17.5 and decreased markedly after birth. Our study is the first to show that RALDH2 and RALDH3, but not RALDH1, are expressed in the embryonic anterior pituitary gland of the rat.
  • Motoshi Kikuchi, Megumi Yatabe, Ken Fujiwara, Shu Takigami, Atsushi Sakamoto, Tsuyoshi Soji, Takashi Yashiro
    ANATOMICAL RECORD PART A-DISCOVERIES IN MOLECULAR CELLULAR AND EVOLUTIONARY BIOLOGY 288A (11) 1183 - 1189 1552-4884 2006/11 [Refereed][Not invited]
     
    In the rat anterior pituitary gland, folliculo-stellate cells aggregate preferably to form pseudofollicles, and each type of hormone-producing cell shows adhesive affinity with particular types of heterologous hormone-producing cells. Distribution of cadherin types in the rat anterior pituitary was examined immunohistochemically to clarify the unique cell arrangements caused by homologous and heterologous affinities among cells. N- and E-cadherins were detected continuously along cell membranes, while P-cadherin was not. N- and E-cadherins showed distinct isolation in localization, with N-cadherins localized in hormone-producing cells of distal and intermediate lobes in various amounts, and E-cadherins limited to folliculo-stellate cells and marginal layer cells facing the residual lumen of Rathke's pouch. A similar distribution of cadherins was observed in cell clusters of primary cultured anterior pituitary cells. These findings suggest that differential expression of cell adhesion molecules may be partially responsible for localization of hormone-producing cells and folliculo-stellate cells.
  • Kazuko Momose, Shin Nunomiya, Masanori Nakata, Toshihiko Yada, Motoshi Kikuchi, Takashi Yashiro
    MEDICAL MOLECULAR MORPHOLOGY 39 (3) 146 - 153 1860-1480 2006/09 [Refereed][Not invited]
     
    The Goto-Kakizaki (GK) rat offers a genetic model of type 2 diabetes and displays profoundly defective insulin secretion leading to basal hyperglycemia. This animal is widely used for studying type 2 diabetes. However, the morphological characteristics of the pancreatic islets of Langerhans in GK rats are not fully understood. The present study sought to clarify this issue using immunohistochemical and electron microscopic techniques. GK rats were killed at 7, 14, 21, and 35 weeks of age. Structural islet changes were not observed at 7 weeks old. At 14 and 21 weeks of age, GK rats displayed histopathological islet changes. The general shape of islets became irregular, and immunoreaction of beta-cells against antiinsulin appeared diffusely weakened. Electron microscopy revealed that the numbers of so-called beta-granules decreased and the numbers of immature granules increased. The Golgi apparatus of beta-cells was developed and the cisternae of rough endoplasmic reticulum were often dilated, indicating hyperfunction of the cells. However, at 35 weeks old, immunoreactivities of dispersed beta-cells into the exocrine portion recovered, and numbers of secretory granules increased again and features of the cell organelles did not display hyperfunction. These results suggest that insulin deficiency in GK rats is not caused by simple dysfunction and/or degeneration of beta-cells but rather by more complicated events within cells.
  • AS Kitaysky, MD Romano, JF Piatt, JC Wingfield, M Kikuchi
    HORMONES AND BEHAVIOR 47 (5) 606 - 619 0018-506X 2005/05 [Refereed][Not invited]
     
    In several seabirds, nutritional state of a nest-bound chick is negatively correlated with the activity of its hypothalamus-pituitary-adrenal (HPA) axis. Increased corticosterone (cort) secretion has been shown to facilitate changes in behavior that allow hungry chicks to obtain more food from parents. However, if parents are not willing/able to buffer their young from temporary food shortages, increased cort secretion could be detrimental to undernourished chicks. In a system where parents are insensitive to chick demands, low benefits and high costs of activation of the HPA-axis in hungry chicks should lead to a disassociation of the nutritional state of the young and the activity of its HPA-axis. We tested this novel hypothesis for the tufted puffin (Fratercula cirrhata), a seabird with intermittent provisioning of a nest-bound semi-precocial chick. We examined the HPA-axis activity of captive chicks exposed to the following: (1) a short-term (24 h) food deprivation; and (2) an array of prolonged (3 weeks) restrictions in feeding regimens. We found that in response to a short-term food deprivation chicks decreased baseline levels of cort and thyroid hormones. In response to prolonged restrictions, food-limited chicks exhibited signs of nutritional deficit: they had lower body mass, endogenous lipid reserves, and thyroid hormone titers compared to chicks fed ad libitum. However, baseline and maximum acute stress-induced levels of cort were also lower in food-restricted chicks compared to those of chicks fed ad libitum. These results support a major prediction of the study hypothesis that puffin chicks suppress HPA-axis activity in response to short- and long-term nutritional deficits. This physiological adaptation may allow a chick to extend its development in the nest, while eluding detrimental effects of chronic cort elevation. (c) 2005 Elsevier Inc. All rights reserved.
  • Sueo Nakama, Motoshi Kikuchi, Takashi Yashiro, Atsushi Sakamoto, Ichiro Kikkawa, Hitoshi Ookami, Kazuo Saita, Yuichi Hoshino
    Medical Molecular Morphology 38 (3) 173 - 180 1860-1480 2005 [Refereed][Not invited]
     
    Ossification or calcification of the ligamentum flavum (LF) is relatively common in the middle and lower cervical, thoracic, and lumbar spine but extremely rare in the upper cervical region. This clinical fact suggests that there exist local factors promoting or preventing ossification or calcification of LF. However, little is known about the differences in the ultrastructure and cellular alterations of the LF between the different spinal levels, even in the cervical spine. With electron microscopy, we examined samples of LF collected surgically from the upper and lower cervical spine regions we then studied the apoptotic appearance of ligament cells using a preferential labeling method. We found direct evidence of apoptosis of ligament cells in the LF. Apoptosis was more apparent in the upper region samples than in the lower region samples. The spaces around the normal fibroblasts were filled with thick collagen fibrils, but the collagen fibrils disappeared around the apoptotic bodies and thin fibrils were formed. The difference of the level of apoptosis may correlate to the ultrastructual difference of LF, and our data will benefit further investigations seeking to clarify the mechanism of various pathological conditions in the human LF. © The Japanese Society for Clinical Molecular Morphology 2005.
  • Yuanyuan Zhang, Yoshinori Jinbu, Hiroto Itoh, Mikio Kusama, Keiichi Tsukinoki, Motoshi Kikuchi, Takashi Yashiro
    Oral Medicine & Pathology 10 (3) 89 - 94 1342-0984 2005 [Refereed]
  • Motoshi Kikuchi, Kaori Sunaga, Megumi Yatabe, Shu Takigami, Atsushi Sakamoto, Takashi Yashiro
    Acta Histochemica et Cytochemica 38 (6) 381 - 386 0044-5991 2005 [Refereed][Not invited]
     
    Different types of integrin alpha subunit were investigated immunohistochemically to determine the relationship between the cell adhesion molecule and the local morphology of the rat anterior pituitary using anterior pituitary tissues and primary cultured cells. Alpha 3 subunit was shown to be the main integrin subunit in the anterior pituitary. In vitro, immunoreactions of α3 subunit appeared mainly surrounding cell clusters. The distribution roughly overlapped with immunoreaction of laminin, while it was also observed where expression of laminin was negative. When dispersed cells were primary cultured for 2, 3 or 5 days, immunoreaction of α3 subunit was clearly detected in the vicinity of cell membrane throughout the period while that of α5 subunit was not observed on day 2, it was observed as dots in cytoplasm on day 3 and more distinctly as lines in the vicinity of the cell membrane on day 5. Alpha 5 subunit was not detectable in vivo. These results indicate the possibility that integrin α3 subunit not only binds the cells to the basement membrane but also to other extracellular matrix or directly to adjacent cells in the anterior pituitary. In addition, integrin α5 subunit may supplement the function of α3 subunit under certain conditions.
  • N Perfito, AD Tramontin, S Meddle, P Sharp, D Afik, J Gee, S Ishii, M Kikuchi, JC Wingfield
    OECOLOGIA 140 (2) 201 - 210 0029-8549 2004/07 [Refereed][Not invited]
     
    Seasonal temperate zone breeders respond to increasing day length to anticipate the approach of spring breeding conditions. Other (supplementary) environmental cues, such as temperature and precipitation, were historically thought to play unimportant roles in reproductive timing. We demonstrate variation in reproductive timing across small geographic distances by examining the vernal testicular recrudescence of adult song sparrows (Melospiza melodia morphna) breeding in coastal (0-10 in elevation) and montane (280-1220 in elevation) habitats. Each year, these birds experienced the same photoperiod, but were exposed to different supplementary cues that varied with altitude. Coastal birds experienced warmer and more stable temperatures during late winter and early spring than did montane birds. We measured bud opening, emergence of new green shoots, and arthropod biomass to monitor the pace of spring's approach. New spring shoots emerged 2 months earlier on the coast than in the mountains and buds on flowering trees and shrubs also tended to open earlier at the coast. Arthropod biomass was similar in both the mountains and the coast during early spring, and began to increase in early summer. Reproductive morphology (i.e. testis volume and cloacal protuberance length) developed up to 2 months earlier on the coast than in the mountains. Testicular recrudescence occurred earlier on the coast in most years and proceeded at a faster rate in I year. Circulating levels of luteinizing hormone, follicle stimulating hormone and prolactin increased through the season, but did not correlate with differences between sites. Both populations responded similarly when exposed to identical photoperiodic cues in the laboratory. Therefore, we suggest that an integrated response to cues characteristic of location and elevation account for differences in patterns measured in the field.
  • Shirasawa N, Mabuchi Y, Sakuma E, Horiuchi O, Yashiro T, Kikuchi M, Hashimoto Y, Tsuruo Y, Herbert DC, Soji T
    The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology 278 (1) 462 - 473 1552-4884 2004/05 [Refereed][Not invited]
  • Aki Nihei, Kayo Hagiwara, Motoshi Kikuchi, Takashi Yashiro, Yuichi Hoshino
    Anatomical Science International 78 (3) 162 - 167 1447-6959 2003/09 [Refereed][Not invited]
     
    The structure of the ligamentum flavum has yet to be fully elucidated and no studies have investigated fine structural differences at different spinal levels in any animals. The aim of the present study was to clarify structural differences in the ligamentum flavum at different spinal levels (cervical: C3/4 and C5/6 upper thoracic: T2/3 lower thoracic: T9/10 lumbar: L3/4) using light and electron microscopy of rabbit specimens. Light microscopy using resorcin-fuchsin staining revealed that the distribution of elastic fibers was diffuse in the cervical and upper thoracic regions, but was generally dense in the lower thoracic and lumbar regions. Electron microscopy demonstrated that the cervical and upper thoracic regions were rich in collagen fibers. Conversely, the lower thoracic and lumbar regions were rich in elastic fibers. Quantitative image analyses displayed thick elastic fibers in the lower thoracic and lumbar regions, with high area ratios. Radiographic examinations revealed that ranges of motion were large at the cervical region, but small at the lower thoracic and lumbar regions. These findings suggest that structure of the ligamentum flavum varies at different spinal levels with respect to differences in motion.
  • Noda T, Kikuchi M, Kaidzu S, Yashiro T
    The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology 272 (2) 548 - 555 1552-4884 2003/06 [Refereed][Not invited]
  • Munetada Kamimoto, Motoshi Kikuchi, Takashi Yashiro, Aki Nihei, Yusei Kariya, Yuichi Hoshino
    Journal of Orthopaedic Science 8 (3) 400 - 407 0949-2658 2003 [Refereed][Not invited]
     
    To investigate the proliferative potencies of the two types of synovial lining cells (types A and B), we used immunohistochemical techniques under light and electron microscopy to survey the complete process of arthritis in a rat model system. Complete Freund's adjuvant (0.1 ml) containing 5 mg of heat-inactivated Mycobacterium butyricum was administered intradermally into the right hind paws of 25 male Sprague-Dawley rats. Five animals were killed at weeks 1, 2, 3, and 4 after the immunological challenge, respectively, and the infrapatellar adipose synovium was removed from each animal. Using proliferative cell nuclear antigen (PCNA) as a cell proliferation marker, we quantified the locations of proliferative cells under light microscopy and then identified the cell type with immunoelectron microscopy. The number of PCNA-positive cells was high in the deep layer at week 2, and most of them were determined to be B cells. At week 3, the number of PCNA-positive cells increased in the superficial layer, and most were identified as A cells. Our results support the idea that cells of the synovial lining proliferate in situ during the course of arthritis.
  • M.A. Ottinger, K. Kubakawa, M. Kikuchi, N. Thompson, S. Ishii
    Experimental Biology and Medicine 227 (9) 830 - 836 1535-3702 2002/10 [Refereed]
     
    During aging, the male Japanese quail exhibits a loss of fertility, increased morphological abnormalities in the testes, and a higher incidence of Sertoli cell tumors. Although there is a co-incident loss of reproductive behavior, plasma androgen levels remain high until testicular regression occurs in association with senescence. The purpose of this study was to compare mean specific binding of chicken luteinizing hormone (LH) and follicle-stimulating hormone (FSH) as a measure of testicular receptors during identified stages during aging. Males were categorized according to age (young = 9 months, middle aged = 24 months, or old = 36+ months) and sexual behavior (active or inactive). Testicular samples were collected immediately after perfusion with 4% paraformaldehyde from the following groups: young active (n = 8), young photoregressed (n = 5), young photoregressed plus testosterone implant (n = 4), middle-aged active (n = 8), middle-aged inactive (n = 4), old inactive (n = 5), and old inactive plus testosterone implant (n = 6). A crude plasma membrane fraction was prepared from the testes of each bird and an aliquot deriving from 10 mg of testicular tissue was used for binding assay. Specific binding of labeled LH or FSH was expressed as percentage of total radioactive hormone. Results showed significant (P < 0.05) age-related decreases in both FSH and LH receptor numbers. The highest FSH binding was found in young and middle-aged active males, with low binding in old inactive males. Testicular LH binding decreased during aging, with a sharp decrease in middle-aged males, which was similar to old males. Testosterone implants weakly stimulated FSH and LH binding in old males. Both LH and FSH binding decreased in photoregressed young males. However, testosterone implants stimulated increased LH binding, but did not affect FSH binding in young photoregressed males. These results provide evidence for separate regulation of testicular LH and FSH receptors, with testosterone stimulation of LH receptor, but not FSH receptor number in young males. However, during aging there appears to be a loss of this response, potentially because of the reduced efficacy of testosterone stimulation, thereby implying a diminished capacity for response with aging.
  • Sex Identification of the Japanese Crested Ibis, Nipponia nippon, by Chromodomain Helicase DNA Binding Protein (CHD) Gene Analysis
    Kikuchi M, Ishii, S
    J Yamashina Inst Ornithol. 33 189 - 197 2002 [Refereed]
  • Application of the Techniques in Molecular and Cellular Biology to Conservation of Endangered Birds
    Motoshi Kikuchi, Daisuke Kawasaki, Susumu Ishii
    Recent Advances in Comparative Endocrinology 387 - 392 2001 [Refereed][Invited]
  • Topographic Affinities of Hormone-Producing Cells in the Rat Anterior Pituitary Gland
    Noda T, Kaidzu S, Kikuchi M, Yashiro T
    Acta Histochem Cytochem 34 313 - 319 2001 [Refereed]
  • Reiko Okada, Takeo Iwata, Takafumi Kato, Motoshi Kikuchi, Kazutoshi Yamamoto, Sakae Kikuyama
    General and Comparative Endocrinology 119 (2) 224 - 231 0016-6480 2000/08 [Refereed]
  • Kazuyoshi Tsutsui, Etsuko Saigoh, Kazuyoshi Ukena, Hitoshi Teranishi, Yuko Fujisawa, Motoshi Kikuchi, Susumu Ishii, Peter J. Sharp
    Biochemical and Biophysical Research Communications 275 (2) 661 - 667 0006-291X 2000/08 [Refereed]
  • Biology of a critically endangered species, the toki (Japanese crested ibis) Nipponia Nippon
    Wingfield JC, Ishii S, Kikuchi M, Wakabayashi S, Sakai H, Yamaguchi N, Wada M, Chikatsuji K
    Ibis 142 1 - 11 2000 [Refereed]
  • B. Silverin, M. Kikuchi, S. Ishii
    General and Comparative Endocrinology 113 (3) 457 - 463 0016-6480 1999/03 [Refereed]
  • Changes in plasma levels of prolactin, luteinizing hormone and progesterone in relation to breeding activities in the bull-headed shrike (Lanius bucephalus)
    Kikuchi M, Ishii S, Imanishi S, Kansaku N, Shimada K
    Recent Progress in Molecular and Comparative Endocrinology 471 - 476 1999 [Refereed][Invited]
  • Kazuyoshi Tsutsui, Dan Li, Kazuyoshi Ukena, Motoshi Kikuchi, Susumu Ishii
    Endocrinology 139 (10) 4230 - 4236 0013-7227 1998/10 [Refereed]
  • Cloning of complementary deoxyribonucleic acid for the follicle-stimulating hormone-beta subunit in the Japanese quail
    M Kikuchi, M Kobayashi, T Ito, Y Kato, S Ishii
    General and Comparative Endocrinology 111 (2) 376 - 385 1998/09 [Refereed]
  • Expression of adenohypophyseal hormone genes in metamorphosing bullfrog larvae
    Kikuyama S, Aida T, Iwata T, Kato T, Okada R, Kikuchi M, Takahashi N, Yamamoto K
    Recent Development in Comparative Endocrinology and Neurobiology 274 - 276 1998 [Refereed]
  • B. Silverin, M. Kikuchi, S. Ishii
    General and Comparative Endocrinology 108 (3) 366 - 373 0016-6480 1997/12 [Refereed]
  • M Kikuchi, S Ishii
    ADVANCES IN COMPARATIVE ENDOCRINOLOGY, TOMES 1 AND 2 1393 - 1398 1997 [Refereed][Not invited]
     
    To estimate gonadal and adrenocortical endocrine activities of birds without disturbing them, we have devised methods for extracting and measuring steroid hormones in excreted feces. Methods needed for proper extraction of steroid hormones differed among species and included a simple extraction with water, an extraction with ethanol-acetone followed by an LH-20 column chromatography or an extraction with ether followed by a reverse phase HPLC. Samples thus prepared were analyzed for steroid hormones by radioimmunoassays. Preliminary experiments using Japanese quail showed that fecal steroid levels reflect plasma levels and hence the endocrine activity as well. Based on this experience, we proceeded to examine reproductive capacities of Japanese crested ibis, an endangered species with only one male and female were surviving in Japan in 1995, and also to study seasonal changes in gonadal and adrenocortical activities of wild rock ptarmigan. Clear changes in sex steroids and corticosterone were observed in the rock ptarmigan.
  • Hormonal induction of ovulation and oviposition in Japanese quail kept under a short-day regimen
    Wakabayashi S, Kikuchi M, Ishii S
    Poult Avi Biol Rev 7 183 - 192 1996 [Refereed]
  • Susumu Ishii, Kaoru Kubokawa, Motoshi Kikuchi, Hiroshi Nishio
    Zoological Science 12 (4) 475 - 484 0289-0003 1995/08 [Refereed]
  • J.X. Wilson, H. Sawai, M. Kikuchi, K. Kubokawa, S. Ishii
    General and Comparative Endocrinology 98 (3) 303 - 310 0016-6480 1995/06 [Refereed]
  • Susumu Ishii, Masaru Wada, Shuichi Wakabayashi, Hidetsugu Sakai, Yoshinori Kubodera, Nobuyuki Yamaguchi, Motoshi Kikuchi
    Journal of Biosciences 19 (4) 491 - 502 0250-5991 1994/10 [Refereed]
  • S. Wakabayashi, M. Kikuchi, M. Wada, H. Sakai, S. Ishii
    British Poultry Science 33 (4) 847 - 858 0007-1668 1992/09 [Refereed]
  • M KIKUCHI, S ISHII
    GENERAL AND COMPARATIVE ENDOCRINOLOGY 85 (1) 124 - 137 0016-6480 1992/01 [Refereed][Not invited]
  • 黄体形成ホルモン受容体の変化が卵成熟過程において果たす役割
    菊地元史
    1991 [Refereed]
  • M KIKUCHI, S ISHII
    BIOLOGY OF REPRODUCTION 41 (6) 1047 - 1054 0006-3363 1989/12 [Refereed][Not invited]

MISC

Awards & Honors

  • 2018/08 日本下垂体研究会 吉村賞
     
    受賞者: 菊地元史
  • 1996 日本動物学会 Zoological Science Award
     
    受賞者: 菊地元史

Research Grants & Projects

  • Elucidating the neural basis of the effect of personality characteristics on motor learning function
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
    Date (from‐to) : 2020/04 -2025/03 
    Author : 板井 美浩, 菊地 元史, 高瀬 堅吉
  • 位相連鎖の可変性が個体行動に与える影響の包括的検討-ヘッブの理論の拡張を目指して
    日本学術振興会:科学研究費助成事業 基盤研究(C)
    Date (from‐to) : 2019/04 -2024/03 
    Author : 高瀬 堅吉, 菊地 元史
     
    本研究では、成体期の雄性マウスに逆転学習課題を課し、その後、感覚運動機能、不安行動、社会行動、抑うつ行動を調べる複数のテストを組み合わせた行動テストバッテリーを課す。すべての実験終了後に、逆転学習課題の結果から位相連鎖の可変性が高い個体、低い個体を抽出し、行動テストバッテリーにおける各個体の結果を比較することで、個体行動全般における位相連鎖の役割を明らかにすることを目的に実験を行う。1クール(5週間)につき10匹を対象にサンプリングを行う。総計200匹まで、最大で20クールにわたり行動解析を実施してデータを得る。 昨年度は逆転学習機能測定で用いるバーンズ迷路テストのセットアップを行い、当該実験系を確立した。また、感覚運動機能測定で用いる視覚性置き直しテスト、プライエル驚愕反射テスト、二瓶選択テスト、嗅覚性馴化脱馴化テスト、フォンフレイ・フィラメントテスト、ホットプレートテスト、ビームテスト、ロータロッドテスト、フットプリントテスト、ワイアハングテストのセットアップも行った。さらに、不安行動測定に用いるオープンフィールドテスト、明暗選択テストや、社会行動測定に用いる社会的行動測定テスト、チューブテスト、性行動測定テスト、最後に、抑うつ行動測定に用いる強制水泳テスト、尾懸垂テストのセットアップも行い、すべての実験系を確立した。研究期間内に上記測定系で総計200匹のマウスの行動解析を終えるよう、実験を進めている。
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    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
    Date (from‐to) : 2020/04 -2023/03 
    Author : 菊地 元史, 早川 盛禎, 高瀬 堅吉
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    Author : 屋代隆
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    日本学術振興会:基盤研究(C)
    Date (from‐to) : 2009/04 -2011/03 
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    日本学術振興会:基盤研究(C)
    Date (from‐to) : 2007/04 -2009/03 
    Author : 屋代隆
  • 脳下垂体ホルモンの進化
    日本学術振興会:一般研究(A)
    Date (from‐to) : 1992/04 -1995/03 
    Author : 石居進

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