医学部 解剖学講座

長内 康幸

オサナイ ヤスユキ  (Yasuyuki Osanai)

基本情報

所属
自治医科大学 医学部 解剖学講座 組織学部門 講師
学位
博士(理学)(総合研究大学院大学)

研究者番号
90758004
J-GLOBAL ID
202001007587820189
researchmap会員ID
R000006728

論文

 17
  • Yasuyuki Osanai, Yao Lulu Xing, Shinya Mochizuki, Kenta Kobayashi, Jihane Homman-Ludiye, Amali Cooray, Jasmine Poh, Ayumu Inutsuka, Nobuhiko Ohno, Tobias D. Merson
    Molecular Therapy - Methods and Clinical Development 32(3) 101288-101288 2024年9月  査読有り
  • Yao Lulu Xing, Jasmine Poh, Bernard H A Chuang, Kaveh Moradi, Stanislaw Mitew, William D Richardson, Trevor J Kilpatrick, Yasuyuki Osanai, Tobias D Merson
    Cell reports methods 3(2) 100414-100414 2023年2月27日  
    Approaches to investigate adult oligodendrocyte progenitor cells (OPCs) by targeted cell ablation in the rodent CNS have limitations in the extent and duration of OPC depletion. We have developed a pharmacogenetic approach for conditional OPC ablation, eliminating >98% of OPCs throughout the brain. By combining recombinase-based transgenic and viral strategies for targeting OPCs and ventricular-subventricular zone (V-SVZ)-derived neural precursor cells (NPCs), we found that new PDGFRA-expressing cells born in the V-SVZ repopulated the OPC-deficient brain starting 12 days after OPC ablation. Our data reveal that OPC depletion induces V-SVZ-derived NPCs to generate vast numbers of PDGFRA+NG2+ cells with the capacity to proliferate and migrate extensively throughout the dorsal anterior forebrain. Further application of this approach to ablate OPCs will advance knowledge of the function of both OPCs and oligodendrogenic NPCs in health and disease.
  • Reiji Yamazaki, Yasuyuki Osanai, Tom Kouki, Jeffrey K Huang, Nobuhiko Ohno
    Neurochemistry international 164 105505-105505 2023年2月6日  
    Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system characterized by remyelination failure, axonal degeneration, and progressive worsening of motor functions. Animal models of demyelination are frequently used to develop and evaluate therapies for MS. We recently reported that focal internal capsule (IC) demyelination in mice with lysophosphatidylcholine injection induced acute motor deficits followed by recovery through remyelination. However, it remains unknown whether the IC demyelination mouse model can be used to evaluate changes in motor functions caused by pharmacological treatments that promote remyelination using behavioral testing and histological analysis. In this study, we examined the effect of clemastine, an anti-muscarinic drug that promotes remyelination, in the mouse IC demyelination model. Clemastine administration improved motor function and changed forepaw preference in the IC demyelinated mice. Moreover, clemastine-treated mice showed increased mature oligodendrocyte density, reduced axonal injury, an increased number of myelinated axons and thicker myelin in the IC lesions compared with control (PBS-treated) mice. These results suggest that the lysophosphatidylcholine-induced IC demyelination model is useful for evaluating changes in motor functions following pharmacological treatments that promote remyelination.
  • Batpurev Battulga, Kazuhiro Shiizaki, Yutaka Miura, Yasuyuki Osanai, Reiji Yamazaki, Yoshiaki Shinohara, Yoshiyuki Kubota, Toru Hara, Makoto Kuro-O, Nobuhiko Ohno
    Scientific reports 13(1) 852-852 2023年1月16日  
    Calcium phosphate forms particles under excessive urinary excretion of phosphate in the kidney. While the formation of calcium phosphate particles (CaPs) has been implicated in the damage to renal tubular cells and renal dysfunction, clarifying the ultrastructural information and the elemental composition of the small CaPs in the wide areas of kidney tissue has been technically difficult. This study introduces correlative and sequential light as well as electron microscopic CaP observation in the kidney tissue by combining fluorescent staining for CaPs and energy-dispersive X-ray spectroscopy (EDS) in scanning electron microscopy (SEM) on resin sections prepared using high-pressure freezing and freeze substitution. CaPs formed in mouse kidneys under long-term feeding of a high-phosphate diet were clearly visualized on resin sections by fluorescence-conjugated alendronate derivatives and toluidine blue metachromasia. These CaPs were verified by correlative observation with EDS. Furthermore, small CaPs formed in the kidney under short-term feeding were detected using fluorescent probes. The elemental composition of the particles, including calcium and magnesium, was identified following EDS analyses. These results suggest that the correlative microscopy approach is helpful for observing in situ distribution and elemental composition of CaPs in the kidney and contributing to studies regarding CaP formation-associated pathophysiology.
  • Yasuyuki Osanai, Batpurev Battulga, Reiji Yamazaki, Tom Kouki, Megumi Yatabe, Hiroaki Mizukami, Kenta Kobayashi, Yoshiaki Shinohara, Yumiko Yoshimura, Nobuhiko Ohno
    Neurochemical research 47(9) 2815-2825 2022年8月6日  
    An appropriate sensory experience during the early developmental period is important for brain maturation. Dark rearing during the visual critical period delays the maturation of neuronal circuits in the visual cortex. Although the formation and structural plasticity of the myelin sheaths on retinal ganglion cell axons modulate the visual function, the effects of dark rearing during the visual critical period on the structure of the retinal ganglion cell axons and their myelin sheaths are still unclear. To address this question, mice were reared in a dark box during the visual critical period and then normally reared to adulthood. We found that myelin sheaths on the retinal ganglion cell axons of dark-reared mice were thicker than those of normally reared mice in both the optic chiasm and optic nerve. Furthermore, whole-mount immunostaining with fluorescent axonal labeling and tissue clearing revealed that the myelin internodal length in dark-reared mice was shorter than that in normally reared mice in both the optic chiasm and optic nerve. These findings demonstrate that dark rearing during the visual critical period affects the morphology of myelin sheaths, shortens and thickens myelin sheaths in the visual pathway, despite the mice being reared in normal light/dark conditions after the dark rearing.

MISC

 14

講演・口頭発表等

 3

共同研究・競争的資金等の研究課題

 7