[Effect of icariin on hypoxia/reoxygenation injury in neonatal rat cardiomyocytes].

OBJECTIVE: To investigate the effect of icariin on myocardial hypoxia reoxygenation injury and the possible mechanism. METHODS: Neonatal Sprague-Dawley rat cardiomyocytes in primary culture were treated with different concentrations of icariin for 24 h prior to hypoxia/reoxygenation injury. Cardiomyocyte apoptosis was evaluated with Tunel staining. The expression levels of apoptosis proteins were detected by Western blotting. The nuclear translocation of p65 was evaluated by immunofluorescence. The p65 signaling pathway was also detected by Western blotting. RESULTS: Myocardial apoptosis rate significantly increased after hypoxia/reoxygenation (control: 1.5% ± 0.1%; MODEL: 23.4% ± 1.3%, P<0.05). While icariin significantly reduced cardiomyocyte apoptosis induced by hypoxia/reoxygenation (1 µmol/L icariin: 7.2% ± 0.9%; 10 µmol/L icariin: 3.9% ± 0.8%, both P<0.05). Western blot showed that the expression levels of pro-apoptotic protein, Bax, increased significantly (control: 0.19 ± 0.05; MODEL: 0.41 ± 0.03, P<0.05), while the expression of anti-apoptotic protein, B-Cell CLL/Lymphoma 2 (BCL-2), was significantly reduced (control: 0.15 ± 0.02; MODEL: 0.03 ± 0.01, P<0.05) after hypoxia/reoxygenation. Notably, icariin reduced the expression of Bax (1 µmol/L icariin: 0.29 ± 0.01; 10 µmol/L icariin: 0.33 ± 0.03, both P<0.05) and increased expression of BCL-2 (1 µmol/L icariin: 0.10 ± 0.03; 10 µmol/L icariin: 0.11 ± 0.02, both P<0.05). Immunofluorescence showed that NFκB-p65 nuclear translocation in cardiomyocytes was increased after hypoxia/reoxygenation (control: 3.6% ± 0.5%; MODEL: 89.5% ± 4.8%, P<0.05), while icariin reduced the nuclear translocation of p65 (1 µmol/L icariin: 32.6% ± 2.3%; 10 µmol/L icariin: 10.6% ± 1.0%, both P<0.05). Moreover, icariin reduced the activation of p65 and phosphorylation of IKBα induced by hypoxia/reoxygenation in cardiomyocytes. CONCLUSION: Icariin can protect cardiomyocytes against hypoxia reoxygenation injury, which may be via blocking p65 signaling pathway.

The effect of polymorphisms (M235T and T174M) on the angiotensinogen gene (AGT) in coronary artery disease in the Eastern Asian population: A systematic review and meta-analysis.

BACKGROUND: It is thought that genetic factors may play an important role in the development of coronary artery disease (CAD). Several studies report that AGT polymorphism is implicated in CAD susceptibility, but these results contradict those of the other studies with the associations being unclear in the Eastern Asian population. Therefore, meta-analysis was performed to evaluate this relationship. METHODS: Publication databases were used to search for eligible relevant studies and valid data were extracted from studies meeting the inclusion criteria. Subsequently, odds ratios (ORs) with 95 % confidence intervals (CIs), were used to assess the strength of the association between AGT polymorphism and CAD risk. RESULTS: Seven eligible studies published only in English were included in the present meta-analysis. In the Eastern Asian population, CAD susceptibility was shown to be related to AGT M235T under the heterozygote model (OR = 0.19). Stratified analysis indicated there was a significant relationship between AGT M235T and CAD risk in China under allelic (OR = 1.34), dominant (OR = 1.43), and heterozygote (OR = 1.62) models. The results showed that the T174M polymorphism was significantly associated with CAD risk in recessive (OR = 2.28) and homozygote (OR = 2.37) models in the Eastern Asian population. CONCLUSIONS: In the Eastern Asian population, especially the Chinese, the M235T of AGT is associated with CAD susceptibility. The T174M polymorphisms were associated with CAD risk in the Eastern Asian population.