[show abstract][hide abstract] ABSTRACT: BACKGROUND: Cardiomyocytes apoptosis is an important contributor to myocardial dysfunction and heart failure. Adiponectin has cardioprotective effects, potential mechanisms behind it are not clear in cardiomyocytes. The purpose of the study was to investigate whether adiponectin can block palmitate-induced apoptosis and the underlying biochemical mechanism in H9c2 cells. METHODS: H9c2 cells were treated with palmitate presence or absence of 2.5 mug/mL globular adiponectin. The effect on the cell viability of H9c2 cells was evaluated using MTT assay, and cell apoptosis was determined by Hoechst 33342 staining. Protein expression was measured using the western blot method. RESULTS: Our results showed that the palmitate treatment induced apoptosis in H9c2 cells, which was associated with increasing the level of cleaved caspase-3 and cleaved PARP. Meanwhile, palmitate-induced apoptosis increased the protein level of p-ERK1/2, and decreased the protein level of p-Akt significantly. However, levels of both of these proteins were restored to the normal when pretreated with adiponectin, and followed with the decrease of cleaved caspase-3 and cleaved PARP. In line with these results, the protective effect of adiponectin can be blocked by PI3K/Akt inhibitor LY294002, and palmitate-induced apoptosis can be attenuated by ERK1/2 inhibitor U0126. CONCLUSIONS: Taken together, the present study demonstrated that adiponectin protects H9c2 cells from palmitate-induced apoptosis via PI3K/Akt and ERK1/2 signaling pathways. Our results reveal a link between adiponectin and cardiomyocytes apoptosis, suggesting that adioponectin may be a promising therapeutic for the treatment of lipotoxicity cardiomyopathy.
Lipids in Health and Disease 10/2012; 11(1):135. · 2.02 Impact Factor
[show abstract][hide abstract] ABSTRACT: Objective: Several groups have reported the important role of the estradiol/testosterone (E(2)/T) ratio in benign prostatic hyperplasia and cerebral vessels. However, there has been no study on the role of the E(2)/T ratio in women with coronary heart disease (CHD). This study aimed to evaluate the association among the ratio of sex hormones and known risk factors of atherosclerosis in postmenopausal women with CHD. Methods: 114 controls and 124 postmenopausal women with CHD were selected for this study. Serum levels of estradiol, testosterone, aromatase, sex hormone-binding globulin (SHBG), lipid-lipoprotein profile and high-sensitivity C-reactive protein were determined. Results: Compared with the control, the E(2)/T ratio decreased from 5.35 ± 2.78 to 3.88 ± 2.51 (p < 0.0001). Multiple linear regression analysis showed that the E(2)/T ratio was negatively associated with total cholesterol, low-density lipoprotein cholesterol (LDL-c) and the atherogenic index of plasma, but positively associated with high-density lipoprotein cholesterol (HDL-c) and HDL-c/LDL-c (for all, p < 0.0001). We found that there was a negative correlation between the E(2)/T ratio and aromatase (r = -0.192, p = 0.032) and a positive correlation between aromatase and SHBG (r = 0.938). Conclusion: The balance of the serum E(2)/T ratio was broken in the women with CHD, and an imbalanced E(2)/T ratio showed a strong association with cardiovascular risk factors in postmenopausal women with CHD.
[show abstract][hide abstract] ABSTRACT: Estrogens protect the vascular system in women, but its effect in men is unclear. We evaluated the impact of estrogen on the male cardiovascular system. Of 140 Chinese males, 55 (aged 61.2 ± 3.5) were cases and 60 (aged 59.5 ± 4.6) were controls. Compared with the control group, only serum estradiol ([E2]; P < .01) levels but not testosterone ([T]; P = .21) were significantly lower in the cases. Linear and multiple regression analysis showed that serum T was positively associated with triglycerides ([TG]; r = .439, P < .01) and d-dimer (r = .258, P < .05) but negatively associated with high-density lipoprotein cholesterol (HDL-C) levels (r = -.267, P < .05) and C-reactive protein (CRP; r = -.214, P < .05). Estradiol was highly associated with TG (r = .783, P < .01) and HDL-C (r = .515, P < .01) but was negatively related with low-density lipoprotein cholesterol (LDL-C; P < .05), total cholesterol/HDL-C (P < .05), CRP (P < .01), and d-dimer (P < .01). In conclusion, serum E2 and T levels affect coronary heart disease risk factors in males.