Losartan reduced connexin43 expression in left ventricular myocardium of spontaneously hypertensive rats / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

<p><b>OBJECTIVE</b>To assess the effect of angiotensin II type 1 (AT(1)) receptor antagonist losartan on myocardium connexin43 (Cx43) gap junction (GJ) expression in spontaneously hypertensive rats (SHRs) and investigate possible mechanisms.</p><p><b>METHODS</b>Sixteen 9-week-old male SHRs and 8 age-matched male Wistar-Kyoto (WKY) rats were included in this study. SHRs were randomly divided into two groups to receive losartan at 30 mg/(kg x d) by oral gavage once daily for 8 weeks (SHR-L) or vehicle (0.9% saline) to act as controls (SHR-V); WKY rats receiving vehicle for 8 weeks served as normotensive controls. At the end of the experiment, rats were sacrificed and the hearts were removed. Expressions of Cx43 and nuclear factor-kappaB p65 (NF-kappaB p65) proteins in all three groups were observed and further investigations on the effect of angiotensin II type 1 receptor antagonist losartan (30 mg/(kg x d), 8 weeks) on Cx43 expression were conducted with Western blot and immunohistochemistry. NF-kappaB p65 protein in nuclear extracts was determined by Western blot.</p><p><b>RESULTS</b>Left ventricular (LV) hypertrophy was prominent in SHRs, Cx43 and NF-kappaB p65 protein expressions were obviously upregulated and Cx43 distribution was dispersed over the cell surface. Treatment with losarton reduced the over-expressions of Cx43 and NF-kappaB p65 in LV myocardium. The distribution of Cx43 gap junction also became much regular and confined to intercalated disk after losartan treatment.</p><p><b>CONCLUSION</b>Cx43 level was upregulated in LV myocardium of SHR during early stage of hypertrophy. Angiotensin II type 1 receptor antagonist losartan prevented Cx43 gap junction remodeling in hypertrophied left ventricles, possibly through the NF-kappaB pathway.</p>

Proteomic analysis of the serum in patients with idiopathic pulmonary arterial hypertension / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Idiopathic pulmonary arterial hypertension (IPAH) is a rare disease of unknown etiology. The exact pathogenesis of pulmonary arterial hypertension is still not well known. In the past decades, many protein molecules have been found to be involved in the development of IPAH. With proteomic techniques, profiling of human plasma proteome becomes more feasible in searching for disease-related markers. In present study, we showed the protein expression profiles of the serum of IPAH and healthy controls after depleting a few high-abundant proteins in serum. Thirteen spots had changed significantly in IPAH compared with healthy controls and were identified by LC-MS/MS. Alpha-1-antitrypsin and vitronectin were down-regulated in IPAH and may be valuable candidates for further explorations of their roles in the development of IPAH.

Atorvastatin prevents connexin43 remodeling in hypertrophied left ventricular myocardium of spontaneously hypertensive rats / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Connexin43 (Cx43) is the predominant gap junction protein in heart and is involved in the control of cell-to-cell communication to modulate the contractility and the electrical coupling of cardiac myocytes. Left ventricular (LV) hypertrophy is accompanied by changes of Cx43 expression. Recent studies have demonstrated that statins reduced cardiac hypertrophy. However, it is unknown whether statins can affect Cx43 expression in hypertrophied left ventricular myocardium. This study was designed to assess the effects of atorvastatin on LV hypertrophy and Cx43 expression in spontaneously hypertensive rats (SHR).</p><p><b>METHODS</b>Nine-week old SHRs were randomly divided into two groups. Some received atorvastatin at 30 mg/kg by oral gavage once daily for 8 weeks (SHR-A); others received vehicle. Age-matched Wistar-Kyoto rats (WKY) received atorvastatin or vehicle for 8 weeks were used as controls. At the end of the experiment, we investigated LV hypertrophy and the expression of Cx43 in LV myocardium in four groups. Cx43 expression was investigated by the methods of Western blotting, immunohistochemistry, and transmission electron microscope. LV hypertrophy was accessed by pathological analysis and plasma brain natriuretic peptide (BNP) level.</p><p><b>RESULTS</b>LV hypertrophy was prominent in untreated SHR. In SHR, LV myocardium Cx43 level was upregulated, and the distribution of Cx43 was displaced from their usual locations to other sites at various distances away from the intercalated disks. After atorvastatin treatment, myocardium Cx43 level was reduced in SHR-A, and the distribution of Cx43 gap junction became much regular and confined to intercalated disk. Statins also prevented LV hypertrophy in SHR.</p><p><b>CONCLUSIONS</b>These results provide novel in vivo evidence for the key role of Cx43 gap junctions in LV hypertrophy and the possible mechanism in anti-hypertrophic effect of statins. Atorvastatin treatment may have beneficial effects on LV hypertrophy in spontaneously hypertensive rats.</p>

PPAR alpha activator fenofibrate regressed left ventricular hypertrophy and increased myocardium PPAR alpha expression in spontaneously hypertensive rats / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the effect of PPAR alpha activator fenofibrate on left ventricular hypertrophy and myocardium PPAR alpha (peroxisome proliferator-activated receptor-alpha) expression in spontaneously hypertensive rats (SHR).</p><p><b>METHODS</b>Sixteen nine-week-old male spontaneously hypertensive rats were randomly divided into two groups: SHR received fenofibrate 100 mg x kg(-1) x d(-1) by oral gavage once daily for 8 weeks (SHR-F, n=8), and SHR received vechile (0.9 % saline) acted as controls (SHR, n=8). Age-matched Wistar-kyoto rats received vehicle for 8 weeks were served as negative controls (WKY, n=8). Systolic blood pressure was measured at the beginning, 2, 4, and 8 weeks of the experiment. At the end of the experiment, plasma BNP (brain natriuretic peptide)and lipid levels were measured. Left ventricular hypertrophy was accessed by pathological analysis. The expression of PPAR alpha and nuclear factor-kappa B (NF-kappa B p65) were investigated by the method of Western blotting.</p><p><b>RESULT</b>Compared with SHR group, systolic blood pressure was slightly lowered in SHR-F group, but it didn't reach significant level(p>0.05). Fenofibrate administration lowered plasma BNP in SHR-F group (P<0.01). There were not much difference of plasma lipid levels between SHR-F and SHR group. Left ventricular mass index (assessed by left ventricular weight/body weight, g x kg(-1)), transdiameter of cardiomyocyte (TDM), cardiomyocyte area (CA), collagen volume fraction (CVF), and perivascular circumferential area (PVCA) decreased significantly in SHR-F group (P<0.05, P<0.01). The myocardium PPAR alpha expression increased significantly (P<0.01), and NF-kappa B p65 expression decreased significantly (P<0.01) in SHR-F group.</p><p><b>CONCLUSION</b>PPAR alpha activator fenofibrate can regress left ventricular hypertrophy and increase myocardium PPAR alpha expression in spontaneously hypertensive rats, which is perhaps independent of its lipid-lowering activity.</p>