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Featured researches published by Hiroshi Niiyama.


Hypertension | 2003

Roles of Intercellular Adhesion Molecule-1 in Hypertensive Cardiac Remodeling

Fumitaka Kuwahara; Hisashi Kai; Keisuke Tokuda; Hiroshi Niiyama; Nobuhiro Tahara; Ken Kusaba; Kiyoko Takemiya; Ali Jalalidin; Mitsuhisa Koga; Tsuyoshi Nagata; Rei Shibata; Tsutomu Imaizumi

Abstract—Recently, we have shown that in rats with a suprarenal abdominal aortic constriction (AC), pressure overload induces early perivascular fibro-inflammatory changes (transforming growth factor [TGF]-&bgr; induction and fibroblast proliferation) within the first week after AC and then causes the development of cardiac remodeling (myocyte hypertrophy and reactive myocardial fibrosis) associated with diastolic dysfunction. Intercellular adhesion molecule (ICAM)-1 is implicated in the recruitment of leukocytes, especially macrophages, in various inflammatory situations. Thus, we sought to investigate the causal relation of ICAM-1 to macrophage recruitment and cardiac remodeling in AC rats. In AC rats, immunoreactive ICAM-1 was observed transiently on endothelial cells of the intramyocardial coronary arterioles after day 1, with a peak at day 3, returning to baseline by day 7. Also, ED1+ macrophage accumulation was found in the area adjacent to the arteries expressing ICAM-1. Chronic treatment with an anti–ICAM-1 neutralizing antibody, but not with control IgG, remarkably reduced the accumulations of macrophages and proliferative fibroblasts and inhibited the upregulation of TGF-&bgr; expression. Furthermore, the neutralizing antibody significantly prevented myocardial fibrosis without affecting arterial pressure and left ventricular and myocyte hypertrophy. In conclusion, ICAM-1 expression was induced by pressure overload in the intramyocardial arterioles, and triggered perivascular macrophage accumulation. In pressure-overloaded hearts, a crucial role in ICAM-1–mediated macrophage accumulation was suggested in the development of myocardial fibrosis, through TGF-&bgr; induction and fibroblast activation.


Journal of Cardiovascular Pharmacology | 2003

Rho-kinase inhibition reduces neointima formation after vascular injury by enhancing Bax expression and apoptosis.

Rei Shibata; Hisashi Kai; Yukihiko Seki; Ken Kusaba; Kiyoko Takemiya; Mitsuhisa Koga; Ali Jalalidin; Keisuke Tokuda; Nobuhiro Tahara; Hiroshi Niiyama; Tsuyoshi Nagata; Fumitaka Kuwahara; Tsutomu Imaizumi

Summary: Recently, we have shown that a specific Rho‐kinase inhibitor, Y27632 (R‐(+)‐trans‐N‐(4‐pyridyl)‐4‐(1‐aminoethyl)‐ cyclohexanecarboxamide), prevents neointima formation after vascular injury associated with increased terminal deoxynucleotidyl transferase‐mediated dUTP nickend labeling (TUNEL)+ smooth muscle cells. Because the mechanism of the action of Y27632 remains unclear, we investigated the expression changes in Bcl family proteins, apoptosis regulators of smooth muscle cells, in the rat carotid artery after balloon injury (BI). Y27632 (BI + Y group) or saline (BI group) was administered peritoneally from Day 1 to Day 14 after BI. Y27632 markedly prevented neointima formation at Day 14. In the BI group, TUNEL+ smooth muscle cells were transiently increased in the neointima, but not in the media, with a peak at Day 7, returning to a lower level by Day 14. Y27632 significantly increased TUNEL+ smooth muscle cells at Days 7 and 14. Smooth muscle cell apoptosis was confirmed by electron microscopic examination. At Day 14, although proapoptotic Bax was slightly, but not significantly, increased in the BI group, it was significantly upregulated in the BI + Y group. Antiapoptotic Bcl‐xL was upregulated in the BI group, and the upregulated Bcl‐xL was not affected by Y27632. These findings indicate that Rho‐kinase inhibition induces neointimal smooth muscle cell apoptosis through Bax upregulation, resulting in reduced neointima formation.


Circulation | 2011

Longest Survivor of Pulmonary Atresia With Ventricular Septal Defect Well-Developed Major Aortopulmonary Collateral Arteries Demonstrated by Multidetector Computed Tomography

Daisuke Fukui; Hisashi Kai; Tomohiro Takeuchi; Takeki Gondo; Toyoharu Oba; Kazutoshi Mawatari; Tatsuo Tonai; Yu Matsuo; Shin-ichiro Ueda; Hiroshi Niiyama; Takafumi Ueno; Tsutomu Imaizumi

A 59-year-old woman was admitted because of cyanosis and dyspnea on exertion and at rest. In her childhood, she was suspected of having ventricular septal defect (VSD), but she refused to undergo cardiac catheterization and operation. Dyspnea on exertion gradually developed after adolescence. On admission, chest roentgenography demonstrated enlarged cardiac silhouette with elevated cardiac apex, a right aortic arch, and enlargement of the main pulmonary arteries and their major branches with increased pulmonary arterial vascularity (Figure 1). Echocardiography revealed a large VSD which lay beneath the dilated aorta that overrides the interventricular septum, hypertrophied right ventricle, and the blind outflow tract of the right ventricle …


Journal of Nutrition Health & Aging | 2017

Effectiveness of cardiac rehabilitation for prevention and treatment of sarcopenia in patients with cardiovascular disease - A retrospective cross-sectional analysis

Haruhito Harada; Hisashi Kai; Hiroshi Niiyama; Yasuhiro Nishiyama; Atsushi Katoh; Noriko Yoshida; Yoshihiro Fukumoto; Hisao Ikeda

ObjectiveSarcopenia is a syndrome characterized by progressive and generalized loss of skeletal muscle mass and strength, with the risk of frailty and poor quality of life. This study aimed to clarify the clinical characteristics of sarcopenia and to investigate the effects of comprehensive cardiac rehabilitation (CCR), including nutrition, physical exercise and medication, in patients with cardiovascular disease (CVD).MethodsWe retrospectively studied 322 inpatients with CVD (age 72±12 years). Muscle mass, muscle strength and physical performance were assessed before and after exercise training in patients with and without sarcopenia, which was defined as either a gait speed of <0.8 m/s or reduced handgrip strength (<26 kg in males and <18 kg in females), together with lower skeletal muscle index (SMI) (<7.0 kg/m2 in males and <5.7 kg/m2 in females). The actual daily total calorie and nutrient intake was also calculated.ResultsSarcopenia was identified in 28% of patients with CVD, these patients having a higher prevalence of symptomatic chronic heart failure and chronic kidney disease. SMI was significantly associated with protein intake and statin treatment. The ratio of peak VO2 and SMI was significantly higher in the statin treatment group. Handgrip strength, gait speed, leg weight bearing index, and nutritional intake improved after exercise training in patients both with and without sarcopenia.ConclusionsThe present findings suggest that CCR is a promising strategy for prevention and treatment of sarcopenia in patients with CVD.


PLOS ONE | 2017

New diagnostic index for sarcopenia in patients with cardiovascular diseases

Haruhito Harada; Hisashi Kai; Rei Shibata; Hiroshi Niiyama; Yasuhiro Nishiyama; Toyoaki Murohara; Noriko Yoshida; Atsushi Katoh; Hisao Ikeda

Background Sarcopenia is an aging and disease-related syndrome characterized by progressive and generalized loss of skeletal muscle mass and strength, with the risk of frailty and poor quality of life. Sarcopenia is diagnosed by a decrease in skeletal muscle index (SMI) and reduction of either handgrip strength or gait speed. However, measurement of SMI is difficult for general physicians because it requires special equipment for bioelectrical impedance assay or dual-energy X-ray absorptiometry. The purpose of this study was, therefore, to explore a novel, simple diagnostic method of sarcopenia evaluation in patients with cardiovascular diseases (CVD). Methods We retrospectively investigated 132 inpatients with CVD (age: 72±12 years, age range: 27–93 years, males: 61%) Binomial logistic regression and correlation analyses were used to assess the associations of sarcopenia with simple physical data and biomarkers, including muscle-related inflammation makers and nutritional markers. Results Sarcopenia was present in 29.5% of the study population. Serum concentrations of adiponectin and sialic acid were significantly higher in sarcopenic than non-sarcopenic CVD patients. Stepwise multivariate binomial logistic regression analysis revealed that adiponectin, sialic acid, sex, age, and body mass index were independent factors for sarcopenia detection. Sarcopenia index, obtained from the diagnostic regression formula for sarcopenia detection including the five independent factors, indicated a high accuracy in ROC curve analysis (sensitivity 94.9%, specificity 69.9%) and the cutoff value for sarcopenia detection was -1.6134. Sarcopenia index had a significant correlation with the conventional diagnostic parameters of sarcopenia. Conclusions Our new sarcopenia index using simple parameters would be useful for diagnosing sarcopenia in CVD patients.


International Heart Journal | 2016

Effect of Exercise Training on Red Blood Cell Distribution Width as a Marker of Impaired Exercise Tolerance in Patients With Coronary Artery Disease

Yasuhiro Nishiyama; Hiroshi Niiyama; Haruhito Harada; Atsushi Katou; Noriko Yoshida; Hisao Ikeda

Red blood cell distribution width (RDW) can predict mortality in cardiovascular disease. However, the underlying mechanisms of the beneficial prognostic marker remain unknown. The purpose of this study was to investigate whether the RDW is related to impaired exercise tolerance and exercise training (ET) effect on RDW in patients with coronary artery disease (CAD).Seventy-eight patients who underwent ET by supervised bicycle ergometer during 3 weeks served as the ET group whereas 30 patients who did not undergo ET were the control group. Exercise stress test with cardiopulmonary analysis was performed in the ET group. Peak oxygen uptake (from 14.1 ± 4.0 to 15.1 ± 3.8 mL/kg/minute, P < 0.05) significantly increased in the ET group. Although RDW and serum erythropoietin concentration (EP) before the observation period did not differ between the ET and control groups, RDW (from 44.4 ± 4.7 to 43.4 ± 3.8 fL, P < 0.01) and EP (from 27.9 ± 15.8 to 22.9 ± 8.2 mIU/mL, P < 0.005) significantly decreased in the ET group, however, these parameters did not change in the control group. In the ET group, RDW was negatively correlated with peak oxygen uptake (r = -0.55, P < 0.01) and the changes in RDW before and after ET were positively correlated with the changes in EP (r = 0.39, P < 0.005).Thus, ET increases exercise tolerance and decreases RDW in association with increased oxygen uptake in patients with CAD.


European Heart Journal | 2015

Demonstration of the disease activity by serial carotid artery ultrasonography, magnetic resonance imaging and 18-fluoro-deoxyglucose positron emission tomography in a Behçet's disease patient with carotid artery stenosis

Sachiyo Igata; Nobuhiro Tahara; Atsuko Tahara; Akihiro Honda; Yoshikazu Nitta; Ken Kusaba; Hiroshi Niiyama; Hayato Kaida; Toshi Abe; Hideki Yoshiyama; Yoshihiro Fukumoto

A 24-year-old female with repeated histories for 6 months of genital ulcer, folliculitis, and oral aphthous ulcers discovered a bruit from right side of her neck by herself. Although carotid ultrasonography and three-dimensional computed tomography demonstrated a diffuse thickening of the intima-media complex in the right common carotid artery (CCA) ( Panel A1 …


Heart Asia | 2014

Systolic blood pressure during recovery from exercise is related to flow-mediated dilatation in patients with coronary artery disease

Yasuhiro Nishiyama; Akiko Sakaue; Sumitake Matsuo; Hiroshi Niiyama; Haruhito Harada; Atsushi Katoh; Hisao Ikeda

Objective To assess the relationship between exercise-induced parameters obtained from the routine exercise stress testing (EST) and flow-mediated vasodilatation (FMD) as an index of endothelial function. Design A retrospective study. Setting Kurume University Medical Center, Kurume, Japan. Patients All patients with stable coronary artery disease (CAD) who were admitted to Kurume University Medical Center. Main outcome measure Results of EST and FMD. Results We studied 66 patients (35 male/31 female) with CAD. All patients underwent symptom-limited EST and measurement of FMD. Exercise parameters included exercise-induced heart rate and systolic blood pressure (SBP). FMD did not differ between male and female groups. In univariate analysis, determinants of FMD included age and the change in SBP at 1 min after exercise. In Cox hazard model analysis, the change in SBP at 1 min after exercise (p=0.011) was an independent determinant of FMD. FMD in patients with abnormal SBP response group was significantly lower than that in normal SBP response group (4.2±1.8 ns. 6.1±2.6%, p<0.05). Conclusions These findings suggest that SBP during recovery from exercise is associated with endothelial function in patients with CAD.


International Heart Journal | 2017

Oral Administration of Glucosamine Improves Vascular Endothelial Function by Modulating Intracellular Redox State

Atsushi Katoh; Hisashi Kai; Haruhito Harada; Hiroshi Niiyama; Hisao Ikeda

Glucosamine, used to treat osteoarthritis, has been shown to have anti-inflammatory and anti-atherosclerotic effects in experimental studies. A recent cohort study has demonstrated that the use of glucosamine was significantly associated with decreased total mortality. Vascular endothelial function is a potent surrogate marker of atherosclerosis and cardiovascular mortality where oxidative stress could participate. Therefore, we investigated whether glucosamine improves vascular endothelial function and intracellular redox state. We examined the effects of oral glucosamine administration (3000 mg/day) for 4 weeks on flow-mediated vasodilation (FMD) and intraerythrocyte glutathione parameters in 20 volunteers. Nineteen age-matched volunteers served as controls. Glucosamine administration significantly increased FMD (from 7.0 ± 2.3 to 8.7 ± 2.3%, P = 0.022). In the control group, FMD did not change. Glucosamine administration significantly increased intraerythrocyte total glutathione levels (from 212.9 ± 46.2 to 240.6 ± 49.4 μmol/L, P = 0.006), intraerythrocyte reduced form of glutathione (GSH) levels (from 124.7 ± 42.6 to 155.2 ± 47.7 μmol/L; P = 0.004) and intraerythrocyte GSH/oxidized form of glutathione (GSSG) ratios (from 3.18 ± 1.64 to 3.88 ± 1.61, P = 0.04). In the control group, any glutathione parameters did not change. Moreover, a stepwise multivariate analysis revealed percent change of GSH/GSSG is the only independent predictor for those of FMD (standardized β = 0.58, P = 0.007) in the glucosamine group. Glucosamine administration improved FMD in association with amelioration of intraerythrocyte GSH/GSSG ratios. These results suggest that oral glucosamine administration might improve vascular endothelial function by modulating intracellular redox state.


Hypertension | 2002

Hypoxia-Inducible Factor-1α/Vascular Endothelial Growth Factor Pathway for Adventitial Vasa Vasorum Formation in Hypertensive Rat Aorta

Fumitaka Kuwahara; Hisashi Kai; Keisuke Tokuda; Rei Shibata; Ken Kusaba; Nobuhiro Tahara; Hiroshi Niiyama; Tsuyoshi Nagata; Tsutomu Imaizumi

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