永井 良三

Accumulation of lipids in the heart may cause cardiac dysfunction in various disorders, such as obesity and diabetes. In the current study, we have investigated whether administration of angiotensin II or norepinephrine induces accumulation of lipids and/or changes in the expression of genes related to lipid metabolism in the rat heart. Lipid deposition was found in myocardial, vascular wall, and perivascular cells of the angiotensin II-infused rat heart, and superoxide generation was increased in these lipid-positive cells. By contrast, intracardiac lipid deposition was not found in the heart of norepinephrine-induced hypertensive rats. Triglyceride content in the heart tissue of angiotensin II-infused rats increased more than 3-fold as compared with untreated controls. Losartan completely, but hydralazine only partially, suppressed the angiotensin II-induced intracardiac lipid deposition and increase in tissue triglyceride content. Administration of angiotensin II upregulated the mRNA expression of sterol regulatory element-binding protein-1c and fatty acid synthase, but downregulated that of uncoupling protein 2 and 3, in a manner dependent on the angiotensin AT1 receptor. Collectively, these results suggest that angiotensin II may be involved in modulating both intracardiac lipid content and lipid metabolism-related gene expression, in part via an angiotensin AT1 receptor-dependent and pressor-independent mechanism. © 2009 Elsevier B.V. All rights reserved.

BACKGROUND: Patients with diabetic retinopathy (DR) have an increased risk of death from coronary heart disease and myocardial infarction. The purpose of this study was to compare the outcomes of revascularization strategies (sirolimus-eluting stent [SES] and coronary artery bypass surgery [CABG]) in patients with DR according to the stage of retinopathy: non-proliferative retinopathy (NPDR) and proliferative retinopathy (PDR). METHODS: From April 2004 until February 2007, 627 patients including 51 NPDR and 62 PDR patients underwent SES implantation. For each retinopathy group, a historical comparison group at the same stages of retinopathy undergoing CABG was selected. Cardiac events were defined as a composite of cardiac death, myocardial infarction, and repeat revascularization. RESULTS: The average follow-up from the time of the initial revascularization was 27.7 ± 8.5 months for NPDR-SES patients, 69.6 ± 36.6 months for NPDR-CABG patients, 26.4 ± 9.7 months for PDR-SES patients, and 68.3 ± 44.2 months for PDR-CABG patients; and Kaplan-Meier estimates of the percentages of events at 24 months were 47.0%, 22.8%, 28.5%, and 26.0%. Kaplan-Meier curves for cardiac events differed significantly between the SES group and the CABG group in NPDR patients (p = 0.04), whereas the curves did not differ significantly between the two groups of PDR patients. The adjusted hazard ratio of SES implantation for cardiac events in the entire group of DR patients was 1.75 (95% confidence interval [CI] 1.02-3.00, p = 0.04). CONCLUSIONS: SES implantation is not a suitable method of revascularization in DR patients, especially in NPDR patients. CABG may become the first-choice revascularization technique for these patients.

The inhibition of apoptotic changes in vascular endothelial cells is important for preventing vascular damage from hypoxia. AMP-activated protein kinase (AMPK) has recently been identified as playing a role in vascular protection. Although the chemical reagent 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside (AICAR) has been used to stimulate AMPK activity, AICAR has been associated with several nonspecific reactions. We therefore constructed a new constitutively active mutant of AMPK alpha 1 (NcaAMPK), which lacks the autoinhibitory domain in AMPK alpha 1 and in which threonine 172 has been replaced with aspartate. We investigated whether NcaAMPK has an anti-apoptotic effect in vascular endothelial cells under anoxic conditions. NcaAMPK, or green fluorescent protein (GFP) as a control, was overexpressed in human umbilical vein endothelial cells (HUVECs). After HUVECs were incubated for 40 h under normoxic or anoxic conditions, we examined cell viability, caspase 3/7 activity, and expression and phosphorylation levels of apoptosis-related proteins. Cell viabilities under anoxic conditions were improved in NcaAMPK-overexpressing cells. Anoxia increased caspase 3/7 activity, but NcaAMPK reduced this increase significantly. NcaAMPK overexpression increased protein kinase B/Akt Ser473 and endothelial nitric oxide synthase Ser1177 phosphorylation, but pretreatment with the nitric oxide synthase inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME) did not decrease the viability of NcaAMPK-overexpressing HUVECs. Furthermore, co-expression of a dominant-negative Akt reduced the improvement in cell viability and the suppression of poly (ADP-ribose) polymerase cleavage by NcaAMPK under anoxic conditions. In conclusion, NcaAMPK inhibited anoxia-induced apoptosis in vascular endothelial cells through Akt activation, suggesting that activation of AMPK might protect against ischemic vascular injury.

Rimonabant has been shown to not only decrease the food intake and body weight but also to increase serum adiponectin levels. This increase of the serum adiponectin levels has been hypothesized to be related to the rimonabant-induced amelioration of insulin resistance linked to obesity, although experimental evidence to support this hypothesis is lacking. To test this hypothesis experimentally, we generated adiponectin knock-out (adipo(-/-))ob/ob mice. After 21 days of 30 mg/kg rimonabant, the body weight and food intake decreased to similar degrees in the ob/ob and adipo(-/-)ob/ob mice. Significant improvement of insulin resistance was observed in the ob/ob mice following rimonabant treatment, associated with significant up-regulation of the plasma adiponectin levels, in particular, of high molecular weight adiponectin. Amelioration of insulin resistance in the ob/ob mice was attributed to the decrease of glucose production and activation of AMP-activated protein kinase (AMPK) in the liver induced by rimonabant but not to increased glucose uptake by the skeletal muscle. Interestingly, the rimonabant-treated adipo(-/-)ob/ob mice also exhibited significant amelioration of insulin resistance, although the degree of improvement was significantly lower as compared with that in the ob/ob mice. The effects of rimonabant on the liver metabolism, namely decrease of glucose production and activation of AMPK, were also less pronounced in the adipo(-/-)ob/ob mice. Thus, it was concluded that rimonabant ameliorates insulin resistance via both adiponectin-dependent and adiponectin-independent pathways.

AIM: Loss or gain in obesity indexes, such as body mass index (BMI) and waist circumference (WC), may affect serum lipid parameters. We therefore analyzed the impact of changes in WC and BMI over a one-year period on serum levels of LDL cholesterol (LDL-C), HDL cholesterol (HDL-C), and triglycerides (TG). METHODS: We analyzed the data of 3,111 individuals who were not on lipid- lowering medication and who underwent general health screening two years running. RESULTS: The correlation between percent changes of WC (%dWC) and BMI (%dBMI) were both statistically significantly correlated with percent changes in LDL-C (%dLDL), HDL-C (%dHDL), and TG (%dTG) except that between %dWC and %dHDL in women. In multiple regression analysis, %dBMI, but not %dWC, was found to be an independent predictor of %dLDL, %dHDL, and %dTG. When %dBMI was excluded from the variables, %dWC was identified as an independent factor predicting %dLDL and %dTG however, in individuals with %dBMI of &gt or =0, %dWC was not found to be a predictor of percent changes in any lipid parameters tested in this model. CONCLUSION: Percent changes in BMI were found to be an independent predictor of adverse changes in lipid parameters in both genders. Although percent changes in WC (%dWC) also tended to confer adverse changes in lipid parameters, this relationship did not remain statistically significant after controlling for %dBMI. It is suggested that changes in obesity parameters are an important goal to avoid adverse lipid changes, although there might be some gender differences.

The objective of this study was to evaluate the efficacy of the Integrating the Healthcare Enterprise (IHE) Echocardiography profile in an environment that included legacy information systems. For this study, we developed an Ultrasound Image and Report Management System that was capable of supporting the IHE echocardiography profile. We then implemented this system at the real clinical environment and integrated it with the existing legacy hospital information system, department system, and picture archive and communication system (PACS). A gateway interface was used to convert the proprietary protocol and data from the legacy systems to support the standard HL7 data format and DICOM connectivity used in newer systems. After a year of operation, we evaluated the efficacy of IHE connectivity by collecting questionnaires and performing interviews to compare system performance before and after the integration. The assessment showed that IHE connectivity provided greater accuracy for measurement data as well as for patient and examination information on the report. The conclusion was that IHE connectivity is effective in environments that mix new standards-based systems with existing legacy information systems.

Recent advances in our understanding of the disease biology of KLFs have spurred considerable interest in their potential to serve as therapeutic targets. Results obtained with small molecules and nucleic acids (e.g., siRNA) targeting KLFs in vitro and in vivo strongly support the feasibility of therapeutic modulation of KLFs for the treatment of cancer as well as cardiovascular and metabolic diseases. Nonetheless, a better understanding of the precise mode of action of KLF in its transcription network, particularly its interaction with other transcription factors and cofactors and its posttranslational modification, would further facilitate development of KLF therapeutics. Moreover, development of improved drug delivery systems would increase the number of diseases that could be targeted by siRNA against KLFs. KLFs have also been used to induce pluripotency in induced pluripotent stem (iPS) cells, suggesting that pharmacological modulation of KLFs may be a useful approach to tailoring iPS cells and their derivatives. © Springer 2009.

The Bartonella species have been recently recognized as important causative agents of culture-negative bacterial endocarditis. Antineutrophil cytoplasmic antibodies (ANCAs) have been associated with the spectrum of idiopathic small vessel vasculitis. However, a variety of infections can result in a false-positive ANCA test, and especially subacute bacterial endocarditis (SBE) with the presence of ANCAs occasionally mimics the clinical manifestations of an ANCA-associated vasculitis such as skin purpura and glomerulonephritis. In contrast, noninfectious endocardial involvement is known to be part of the spectrum of the manifestations of the ANCA-associated vasculitis. Therefore, it is crucial to distinguish an ANCA-positive SBE from an ANCA-associated vasculitis with endocardial compromise, because the misdiagnosis of an SBE as an ANCA-associated vasculitis can lead to an inappropriate immunosuppressive therapy with catastrophic consequences. The differential diagnosis is sometimes difficult, especially in the case of culture-negative infective endocarditis with a positive ANCA test. We describe here a case of a culture-negative SBE caused by Bartonella quintana, accompanied with a positive cytoplasmic ANCA test and clinical findings masquerading as ANCA-associated vasculitis. Both a serological test for Bartonella and polymerase chain reaction restriction fragment length polymorphism analysis were helpful for a correct diagnosis and appropriate treatment. Copyright (C) 2009 S. Karger AG, Basel

Kruppel-like transcription factors (KLFs) participate in diverse physiological and pathological processes, such as cell growth, cell differentiation, tumorigenicity, metabolism, inflammation, and tissue remodeling in response to diverse external stress. The importance of KLFs has recently been appreciated as detailed mechanisms of their molecular functions have been rapidly unraveled. However, many questions remain to be addressed: for instance, (1) how is gene expression of KLFs regulated-in a developmental stage-specific manner or in terms of cell-cell interaction; (2) how do KLFs interplay with other cofactors amid the transcriptional network; and (3) need to explore the tertiary structure of KLFs. Given the importance of KLFs in disease biology, extensive investigations on KLFs are expected to lead to identification of therapeutic targets for many diseases.

Heart transplantation has been broadly performed in humans. However, occurrence of acute and chronic rejection has not yet been resolved. Several inflammatory factors, such as cytokines and adhesion molecules, enhance the rejection. The graft arterial disease (GAD), which is a type of chronic rejection, is characterized by intimal thickening comprised of proliferative smooth muscle cells. Specific treatments that target the attenuation of acute rejection and GAD formation have not been well studied in cardiac transplantation. Recent progress in the nucleic acid drugs, such as antisense oligodeoxynucleotides (ODNs) to regulate the transcription of disease-related genes, has important roles in therapeutic applications. Transfection of cis-element double-stranded DNA, named as "decoy," has been also reported to be a useful nucleic acid drug. This decoy strategy has been not only a useful method for the experimental studies of gene regulation but also a novel clinical strategy. In this paper, we reviewed the experimental results of NF-kappa B, E2F, AP-1, and STAT-1 decoy and other ODNs using the experimental heart transplant models. Copyright (C) 2009 Jun-ichi Suzuki et al.

Tea polyphenols known as catechins are key components with many biological functions, including anti-inflammatory, antioxidative, and anticarcinogenic effects. These effects are induced by the suppression of several inflammatory factors including nuclear factor-kappa B (NF-kappa B). While these characteristics of catechins have been well documented, actions of catechins as mediators on inflammation-related cardiovascular diseases have not yet been well investigated. In this article, we reviewed recent papers to reveal the anti-inflammatory effects of catechins in cardiovascular diseases. In our laboratory, we performed oral administration of catechins into murine and rat models of cardiac transplantation, myocarditis, myocardial ischemia, and atherosclerosis to reveal the effects of catechins on the inflammation-induced ventricular and arterial remodeling. From our results, catechins are potent agents for the treatment and prevention of inflammation-related cardiovascular diseases because they are critically involved in the suppression of proinflammatory signaling pathways. Copyright (c) 2009 Jun-ichi Suzuki et al.

Voltage-gated Na(+) channel currents (I(Na)) are expressed in several types of smooth muscle cells. The purpose of this study was to evaluate the expression of I(Na), its functional role, pathophysiology in cultured human (hASMCs) and rabbit aortic smooth muscle cells (rASMCs), and its association with vascular intimal hyperplasia. In whole cell voltage clamp, I(Na) was observed at potential positive to -40 mV, was blocked by tetrodotoxin (TTX), and replacing extracellular Na(+) with N-methyl-d-glucamine in cultured hASMCs. In contrast to native aorta, cultured hASMCs strongly expressed SCN9A encoding Na(V)1.7, as determined by quantitative RT-PCR. I(Na) was abolished by the treatment with SCN9A small-interfering (si)RNA (P < 0.01). TTX and SCN9A siRNA significantly inhibited cell migration (P < 0.01, respectively) and horseradish peroxidase uptake (P < 0.01, respectively). TTX also significantly reduced the secretion of matrix metalloproteinase-2 6 and 12 h after the treatment (P < 0.01 and P < 0.05, respectively). However, neither TTX nor siRNA had any effect on cell proliferation. L-type Ca(2+) channel current was recorded, and I(Na) was not observed in freshly isolated rASMCs, whereas TTX-sensitive I(Na) was recorded in cultured rASMCs. Quantitative RT-PCR and immunostaining for Na(V)1.7 revealed the prominent expression of SCN9A in cultured rASMCs and aorta 48 h after balloon injury but not in native aorta. In conclusion, these studies show that I(Na) is expressed in cultured and diseased conditions but not in normal aorta. The Na(V)1.7 plays an important role in cell migration, endocytosis, and secretion. Na(V)1.7 is also expressed in aorta after balloon injury, suggesting a potential role for Na(V)1.7 in the progression of intimal hyperplasia.

Accumulating evidence suggests that statins have beneficial effects which are independent of their lipid-lowering actions, on vascular cells. Here, we investigated whether the HMG-CoA reductase inhibitor rosuvastatin can inhibit atherosclerotic lesion development with favorable effects on endothelial cells in ApoE-deficient mice. Rosuvastatin rapidly phosphorylated Akt and endothelial nitric oxide synthase ( eNOS) in human endothelial cells. Endothelial cell death induced by serum starvation was significantly inhibited by rosuvastatin ( percent cell death; 45.9 +/- 2.4% vs. 37.3 +/- 1.1%, p &lt; 0.05). Eight-week-old ApoE-deficient mice were orally administered vehicle or rosuvastatin at a dose of 20 mg/kg/day for 24 weeks. There was no significant difference in cholesterol profile. Rosuvastatin preserved endothelial lining at the aortic root (CD31-positive luminal side; 63.8 +/- 2.8% vs. 81.7 +/- 3.9%, p &lt; 0.05). En face Sudan IV staining of aorta revealed that rosuvastatin significantly decreased the atherosclerotic area (21.9 +/- 2.9% vs. 11.9 +/- 1.9%, p &lt; 0.05). Lipid deposition at the atherosclerotic area was also suppressed by rosuvastatin with more stabilized morphologic features as determined by oil red O staining (3.4 +/- 0.4% vs. 1.7 +/- 0.4%, p &lt; 0.05). Our findings indicate that rosuvastatin protects endothelial cells from death with phosphorylation of Akt and eNOS. These effects may contribute, at least in part, to the anti-atherosclerotic effects of rosuvastatin. (C) 2007 Elsevier Masson SAS. All rights reserved.

【背景】高強度の急性運動で血中CRPが上昇することは知られている。Pentraxin3(PTX3)はCRPと同様のPentraxin Familyに属し、炎症により特異的に発現する蛋白である。我々は、3種類の急性運動に対するPTX3とCRPの反応と運動により誘発される様々なマーカーについて比較検討した。【方法】対象は、健常男性9名(平均年齢41±3歳)。各被験者は、(1)自転車エルゴメーターでの有酸素運動(70%AT)30分間、(2)自転車エルゴメーターでの20watt-Ramp自覚的最大負荷運動(MAX)、(3)70%1RMの下肢レジスタンス運動3種目(レッグプレス、レッグカール、レッグエクステンション)を15回4セットの3種類の運動を行った。静脈採血ではPTX3、高感度CRP(hsCRP)、乳酸(LA)、ノルアドレナリン(NA)、白血球(WBC)、IL-6、顆粒球コロニー刺激因子(G-CSF)、ミエロペルオキシダーゼ(MPO)を測定した。採血ポイントは運動前、運動終了時、運動終了1時間後の計3回行った。【結果】安静時のPTX3とhsCRPに有意な相関はみられなかった。MAX運動とレジスタンス運動では、運動直後にPTX3、hsCRPともに有意な上昇を認めたが、有酸素運動では上昇はみられなかった。IL-6もMAX運動とレジスタンス運動にて増加したが、G-CSFでは有意な増加はみられなかった。安静時を基準としたPTX3、hsCRPの増加率は、WBC、NA、LA、MPOの増加率と有意な相関がみられたが、IL-6の増加率とは相関はみられなかった。さらに、PTX3と相関の強いものはWBC>LA>MPO>NAの順であり、hsCRPではNA>LA>WBC>MPOの順に強い相関があった。PTX3とhsCRPの上昇は、運動終了1時間後には安静時と同程度に戻った。【結語】PTX3はCRPとは異なる特異的な炎症マーカーであり、高強度短時間の急性運動では筋肉などの組織の炎症を反映し、早期に上昇することが判明した。さらにPTX3の上昇には、損傷した筋肉に動員された白血球からの放出などが関与していると考えられた。(著者抄録)

Background: Accumulating evidence indicates that C-reactive protein (CRP) is an independent predictive factor for atherosclerotic vascular disease in Caucasians. Accordingly, this study sought to investigate the relationship between the serum level of CRP and cardiovascular events of Japanese patients with coronary artery disease (CAD). Methods and Results: The Japanese CAD (JCAD) study enrolled 15,628 patients who had significant diameter stenosis (≥75%) in at least 1 coronary artery. Of these, 6,802 patients had their baseline serum CRP data available. Patients were followed up for a mean of 2.7 years (follow-up rate 88.3%). The primary endpoint of the JCAD study was all events. Baseline covariates possibly influencing the event rate were adjusted between the 2 groups with and without elevated serum CRP level. Kaplan-Meier analysis demonstrated a 30% higher all-events rate in patients with a serum level of CRP ≥0.1 mg/dl (P=0.0002). Cox proportional hazard analysis also showed that a serum level of CRP ≥0.1 mg/dl was an independent predictor of all events (P=0.0001), and of cardiac events and cardiac death (P=0.0005). Conclusions: Elevated serum level of CRP is an independent predictor of cardiovascular events in JCAD patients.

Unstable lipid-rich plaques in atherosclerosis are characterized by the accumulation of macrophage foam cells loaded with cholesterol ester (CE). Although hormone-sensitive lipase and cholesteryl ester hydrolase (CEH) have been proposed to mediate the hydrolysis of CE in macrophages, circumstantial evidence suggests the presence of other enzymes with neutral cholesterol ester hydrolase (nCEH) activity. Here we show that the murine orthologue of KIAA1363, designated as neutral cholesterol ester hydrolase (NCEH), is a microsomal nCEH with high expression in murine and human macrophages. The effect of various concentrations of NaCl on its nCEH activity resembles that on endogenous nCEH activity of macrophages. RNA silencing of NCEH decreases nCEH activity at least by 50%; conversely, its overexpression inhibits the CE formation in macrophages. Immunohistochemistry reveals that NCEH is expressed in macrophage foam cells in atherosclerotic lesions. These data indicate that NCEH is responsible for a major part of nCEH activity in macrophages and may be a potential therapeutic target for the prevention of atherosclerosis.

The renin-angiotensin (Ang) system plays a critical role in the regulation of blood pressure, body fluid, electrolyte homeostasis, and organ remodeling under physiological and pathological conditions. The carboxypeptidase ACE2 is a homologue of angiotensin-converting enzyme (ACE). It has been reported that ACE2-deficient mice develop cardiac dysfunction with increased plasma levels of Ang II. However, the molecular mechanism by which genetic disruption of ACE2 results in heart dysfunction is not fully understood. Here, we generated mice with targeted disruption of the Ace2 gene and compared the cardiovascular function of ACE2(-/y) mice with that of their wild-type littermates. ACE2-deficient mice were viable and fertile and lacked any gross structural abnormalities. Echocardiographic study detected no functional difference between ACE2(-/y) and wild-type mice at 12 weeks of age. Twenty-four-week-old ACE2(-/y) mice displayed significantly enlarged hearts with impaired systolic and diastolic function. The Ang II level was elevated in the plasma and heart of ACE2(-/y) mice. Pharmacological blockade of Ang II type 1 receptor (AT1) with candesartan attenuated the development of cardiac dysfunction in ACE2(-/y) mice. These results suggest that enhanced stimulation of AT1 may play a role in the development of cardiac dysfunction observed in ACE2-deficient mice.

Although degradation of cartilage matrix has been suggested to be a rate-limiting step for endochondral ossification during skeletal development, little is known about the transcriptional regulation. This study investigated the involvement of KLF5 (Krüppel-like factor 5), an Sp/KLF family member, in the skeletal development. KLF5 was expressed in chondrocytes and osteoblasts but not in osteoclasts. The heterozygous deficient (KLF5+/-) mice exhibited skeletal growth retardation in the perinatal period. Although chondrocyte proliferation and differentiation were normal, cartilage matrix degradation was impaired in KLF5+/- mice, causing delay in replacement of cartilage with bone at the primary ossification center in the embryonic limbs and elongation of hypertrophic chondrocyte layer in the neonatal growth plates. Microarray analyses identified MMP9 (matrix metalloproteinase 9) as a transcriptional target, since it was strongly up-regulated by adenoviral transfection of KLF5 in chondrogenic cell line OUMS27. The KLF5 overexpression caused gelatin degradation by stimulating promoter activity of MMP9 without affecting chondrocyte differentiation or vascular endothelial growth factor expression in the culture of chondrogenic cells; however, in osteoclast precursors, it affected neither MMP9 expression nor osteoclastic differentiation. KLF5 dysfunction by genetic heterodeficiency or RNA interference was confirmed to cause reduction of MMP9 expression in cultured chondrogenic cells. MMP9 expression was decreased in the limbs of KLF5+/- embryos, which was correlated with suppression of matrix degradation, calcification, and vascularization. We conclude that KLF5 causes cartilage matrix degradation through transcriptional induction of MMP9, providing the first evidence that transcriptional regulation of a proteinase contributes to endochondral ossification and skeletal development.

PURPOSE: In hypertensive patients with diabetes, antihypertensive therapy is important in reducing the risk of macro- and microvascular complications. In contrast to the guidelines issued by the American Diabetes Association (ADA) in and after 2002, the guidelines issued by the Japanese Society of Hypertension (JSH) in 2000 and 2004 maintained the traditional view that beta-blockers and thiazides should be rated as second-line drugs. However, both sets of guidelines recommended angiotensin converting enzyme inhibitors and angiotensin II receptor blockers (ARBs) as first-line agents for such patients. METHODS: We examined the use of antihypertensives in hypertensive patients with and without diabetes using the prescription data for 1999, 2002 and 2005 from three Japanese university hospitals. RESULTS: When compared with 1999, the proportion of patients with and without diabetes using ARBs was dramatically increased in 2005 from 1.5 to 55% and from 1.5 to 40%, while that of angiotensin converting enzyme inhibitors decreased from 52 to 32% and 35 to 23%, respectively. A relatively stable proportion of patients (around 10% with and without diabetes) used beta-blockers and around 60% of patients with and without diabetes used calcium channel blockers (CCBs) and very few (<5%) used thiazides. CONCLUSIONS: The rapid increase in use of ARBs and under-use of thiazides may be explained by the fee schedule in the Japanese health insurance system. The paucity of large-scale clinical trials may also hinder evaluation of the traditional view of the role of beta-blockers and thiazides in treatment of Japanese patients with diabetes.

Stent thrombosis has been recognized as a potentially critical complication in percutaneous coronary intervention. In the bare-metal stent era, stent thrombosis was considered to be an acute or subacute event, occurring within 1 month after stent implantation. Recently, late or very late stent thrombosis after drug-eluting stent implantation has been brought into focus however, the mechanism underlying this potentially fatal event is largely unknown. We report a case of critical late thrombosis 2 years after sirolimus-eluting stent implantation. Detailed serial intravascular ultrasound analyses revealed that late-acquired incomplete stent apposition, accompanied by extensive positive vascular remodeling, was involved in the pathogenesis of the nearly fatal event described in this case.

Self-renewal of embryonic stem cells (ESCs) is maintained by a complex regulatory mechanism involving transcription factors Oct3/4 (Pou5f1), Nanog and Sox2. Here, we report that Klf5, a Zn-finger transcription factor of the Kruppel-like family, is involved in ESC self-renewal. Klf5 is expressed in mouse ESCs, blastocysts and primordial germ cells, and its knockdown by RNA interference alters the molecular phenotype of ESCs, thereby preventing their correct differentiation. The ability of Klf5 to maintain ESCs in the undifferentiated state is supported by the finding that differentiation of ESCs is prevented when Klf5 is constitutively expressed. Maintenance of the undifferentiated state by Klf5 is, at least in part, due to the control of Nanog and Oct3/4 transcription, because Klf5 directly binds to the promoters of these genes and regulates their transcription.

Aim: Previous studies have shown that hepatitis B virus (HBV) and hepatitis C virus (HCV) infection may be associated with glomerulonephritis. Methods: In the current study, we investigated the possible association between HBV/HCV infection, estimated GFR (eGFR) and albuminuria by analyzing cross-sectional data from individuals undergoing general health screening. Results: Of 12 535 individuals enrolled, 130 (1.0%) and 72 (0.6%) tested positive for HBV surface antigen and HCV core antigen, respectively. In comparison with hepatitis-negative individuals, the prevalence of low eGFR and albuminuria was significantly greater in individuals with HCV infection, but not in those with HBV infection. Logistic regression analysis adjusted for age, sex, systolic blood pressure and fasting plasma glucose showed that HCV infection was positively associated with low eGFR (odds ratio 1.63 [95% CI 0.95-2.80, P = 0.077]) and with albuminuria (odds ratio 2.00 [95% CI 1.06-3.76, P = 0.003]). By contrast, prevalence of neither low eGFR nor albuminuria was greater in individuals with HBV infection than in hepatitis-negative subjects. Further adjustment for either HOMA-IR or serum alanine aminotransferase levels abolished the statistical significance in the association between HCV infection and albuminuria. Conclusion: Our data suggest that although both HCV and HBV infection are associated with increased insulin resistance, the different viruses may have different impacts on chronic kidney disease among Japanese individuals undergoing general health screening. © 2008 The Japan Society of Hepatology.

Hormone-sensitive lipase (HSL) regulates the hydrolysis of acylglycerol and cholesteryl ester (CE) in various organs, including adipose tissues. However, the hepatic expression level of HSL has been reported to be almost negligible. In the present study, we found that mice lacking both leptin and HSL (Lep(ob/ob)/HSL(-/-)) showed massive accumulation of CE in the liver compared with Lep(ob/ob)/HSL(+/+) mice, while triacylglycerol (TG) accumulation was modest. Similarly, feeding with a high-cholesterol diet induced hepatic CE accumulation in HSL(-/-) mice. Supporting these observations, we detected significant expression of protein as well as mRNA of HSL in the liver. HSL(-/-) mice showed reduced activity of CE hydrolase, but not of TG lipase, in the liver compared with wild-type mice. Furthermore, we confirmed the expression of HSL in viable parenchymal cells isolated from wild-type mice. The hepatocytes from HSL(-/-) mice showed reduced activity of CE hydrolase and contained more CE than those from HSL(+/+) mice even without the incubation with lipoproteins. Incubation with LDL further augmented the accumulation of CE in the HSL-deficient hepatocytes. From these results, we conclude that HSL is involved in the hydrolysis of CE in hepatocyes.

It has been established that patients with chronic kidney disease (CKD) suffer from frequent cardiovascular events. On the other hand, recent studies suggest that renal damage tends to worsen in patients with cardiovascular diseases (CVD). Although the mechanisms for the cardiorenal association are unclear, the presence of arteriosclerotic risk factors common to both CVD and CKD is important. In arteriosclerosis, vascular derangement progresses not only in the heart but also in the kidney. In addition, heart failure, cardiac catheterization and hesitation of medical treatments due to renal dysfunction may explain the progression of renal damage. Therefore, the goal of treatments is a total control of arteriosclerotic risk factors. Medication should be selected among agents with protective effects on both heart and kidney. It is important to always consider the presence of CKD for the treatment of the cardiovascular disease and strictly control the risk factors.

Insulin receptor substrate (Irs) mediates metabolic actions of insulin. Here, we show that hepatic Irs1 and Irs2 function in a distinct manner in the regulation of glucose homeostasis. The PI3K activity associated with Irs2 began to increase during fasting, reached its peak immediately after refeeding, and decreased rapidly thereafter. By contrast, the PI3K activity associated with Irs1 began to increase a few hours after refeeding and reached its peak thereafter. The data indicate that Irs2 mainly functions during fasting and immediately after refeeding, and Irs1 functions primarily after refeeding. In fact, liver-specific Irs1-knockout mice failed to exhibit insulin resistance during fasting, but showed insulin resistance after refeeding; conversely, liver-specific Irs2-knockout mice displayed insulin resistance during fasting but not after refeeding. We propose the concept of the existence of a dynamic relay between Irs1 and Irs2 in hepatic insulin signaling during fasting and feeding.

AIMS: The early diagnosis of acute aortic dissection (AD) remains challenging. We sought to determine the utility of the troponin-like protein of smooth muscle, calponin, as a diagnostic biomarker of acute AD. METHODS AND RESULTS: Immunoassays against calponin (acidic, basic, and neutral isoforms) were developed and the levels were compared in a convenience sample of 59 patients with radiographically proven AD [34 males, age 59 +/- 15 (SD) years] vs. 158 patients suspected of having AD at presentation (116 males, age 63 +/- 15 years) but whose final diagnosis was not AD. Basic calponin, which is the most specific and abundant in smooth muscle, and acidic calponin, respectively, showed greater than two-fold and three-fold elevations in patients with acute AD. Diagnostic performance as determined by receiver-operating characteristics curve analysis showed that both acidic and basic calponin have the potential to detect AD in the first 24 h [respective areas under the curve (AUCs) 0.63 and 0.58], with superior performance of basic calponin (when compared with acidic) in the initial 6 h (respective AUCs 0.63 and 0.67). CONCLUSION: Circulating calponin levels were elevated in acute AD compared with controls. These biomarkers have the potential for use as an early diagnostic biomarker for acute AD.

We examined whether ANG II and TNF-alpha cooperatively induce vascular inflammation using the expression of monocyte chemoattractant protein (MCP)-1 as a marker of vascular inflammation. ANG II and TNF-alpha stimulated MCP-1 expression in a synergistic manner in vascular smooth muscle cells. ANG II-induced MCP-1 expression was potently inhibited to a nonstimulated basal level by blockade of the p38-dependent pathway but only partially inhibited by blockade of the NF-kappaB-dependent pathway. In contrast, TNF-alpha-induced MCP-1 expression was potently suppressed by blockade of NF-kappaB activation but only modestly suppressed by blockade of p38 activation. ANG II- and TNF-alpha-induced activation of NF-kappaB- and p38-dependent pathways was partially inhibited by pharmacological inhibitors of ROS production. Furthermore, ANG II- and TNF-alpha-stimulated MCP-1 expression was partially suppressed by ROS inhibitors. We also examined whether endogenous ANG II and TNF-alpha cooperatively promote vascular inflammation in vivo using a wire injury model of the rat femoral artery. Blockade of both ANG II and TNF-alpha further suppressed neointimal formation, macrophage infiltration, and MCP-1 expression in an additive manner compared with blockade of ANG II or TNF-alpha alone. These results suggested that ANG II and TNF-alpha synergistically stimulate MCP-1 expression via the utilization of distinct intracellular signaling pathways (p38- and NFkappaB-dependent pathways) and that these pathways are activated in ROS-dependent and -independent manners. These results also suggest that ANG II and TNF-alpha cooperatively stimulate vascular inflammation in vivo as well as in vitro.

It is well known that excessive intake of sodium chloride (sodium) is a risk factor for cardiovascular disease because it raises blood pressure. However, sodium loading reportedly promotes cardiovascular disease independently of its effect on blood pressure. To examine the mechanisms by which sodium loading promotes vascular inflammation independently of its effect on blood pressure, we examined the role of calcineurin in sodium loading-induced vascular inflammation using a wire injury model of the rat femoral artery. Calcineurin mRNA expression in the wire-injured femoral artery was significantly higher in sodium-loaded normotensive rats, such as Wistar-Kyoto (WKY) rats, than that in control WKY rats. Neointimal formation was also significantly enhanced in sodium-loaded WKY rats compared with control WKY rats. Gene transfer of an adenovirus expressing a dominant negative mutant of calcineurin (AdCalADeltaC92Q) significantly suppressed neointimal formation in sodium-loaded WKY rats to a level similar to that observed in control WKY rats. Calcineurin expression and neointimal formation were more significantly enhanced in hypertensive rats, such as spontaneously hypertensive rats (SHRs), than those in control WKY rats. AdCalADeltaC92Q infection significantly suppressed neointimal formation in SHRs to a level similar to that observed in control WKY rats. These results suggest that sodium loading promotes neointimal formation, even in normotensive rats, and that hypertension further stimulates neointimal formation. These results also suggest that calcineurin plays a pivotal role in this process.

Although antihypertensive drugs confer improvement in endothelial dysfunction and protection from atherogenesis in hypertension, different classes of antihypertensive drugs may elicit different degrees of vasculoprotective effects. We have investigated the effects of a long-acting calcium antagonist, benidipine, and an angiotensin AT(1) receptor antagonist, losartan, on the vascular damage observed in OLETF rats, an animal model of metabolic syndrome. At 34 weeks of age, OLETF rats were treated with either benidipine (3 mg/kg/day, per os) or losartan (25 mg/kg/day, per os) for 8 weeks. The extent of blood pressure reduction, restoration endothelium-dependent aortic relaxation, and elevation of serum nitrite/nitrate concentration did not differ significantly between benidipine- and losartan-treated OLETF rats. Benidipine and losartan also reduced the aortic expression of transforming growth factor-beta 1 mRNA and thickening of the vascular wall to a similar extent. Increased cardiac fibrosis was also inhibited by both benidipine and losartan. These data suggest that, when used in an antihypertensive dose, benidipine is as effective as losartan in restoring vascular endothelial function and in suppressing of cardiovascular remodeling in an animal model of metabolic syndrome. (C) 2008 Elsevier B.V. All rights reserved.

We show that transcription factor Krüppel-like factor 5 (KLF5), which is important in cardiovascular remodeling, interacts with retinoic acid receptor-alpha (RARalpha) to regulate downstream gene expression. Here, we investigated whether acyclic retinoid (ACR) regulates KLF5 and inhibits vascular remodeling. Co-immunoprecipitation and pull-down binding assay showed that ACR attenuates functional interaction of KLF5 and RARalpha. ACR affects KLF5 functions by regulating transactivation of platelet-derived growth factor A (PDGF-A) chain. ACR may be a new vascular therapy to target KLF5 in cardiovascular pathology.

AIMS/HYPOTHESIS: A decrease in plasma adiponectin levels has been shown to contribute to the development of diabetes. However, it remains uncertain whether adiponectin plays a role in the regulation of insulin secretion. In this study, we investigated whether adiponectin may be involved in the regulation of insulin secretion in vivo and in vitro. METHODS: The effect of adiponectin on insulin secretion was measured in vitro and in vivo, along with the effects of adiponectin on ATP generation, membrane potentials, Ca2+ currents, cytosolic calcium concentration and state of 5'-AMP-activated protein kinase (AMPK). In addition, insulin granule transport was measured by membrane capacitance and total internal reflection fluorescence (TIRF) analysis. RESULTS: Adiponectin significantly stimulated insulin secretion from pancreatic islets to approximately 2.3-fold the baseline value in the presence of a glucose concentration of 5.6 mmol/l. Although adiponectin had no effect on ATP generation, membrane potentials, Ca2+ currents, cytosolic calcium concentrations or activation status of AMPK, it caused a significant increase of membrane capacitance to approximately 2.3-fold the baseline value. TIRF analysis revealed that adiponectin induced a significant increase in the number of fusion events in mouse pancreatic beta cells under 5.6 mmol/l glucose loading, without affecting the status of previously docked granules. Moreover, intravenous injection of adiponectin significantly increased insulin secretion to approximately 1.6-fold of baseline in C57BL/6 mice. CONCLUSIONS/INTERPRETATION: The above results indicate that adiponectin induces insulin secretion in vitro and in vivo.