当归多糖通过上调VEGF抑制细胞凋亡

本研究旨在探讨当归多糖减轻糖尿病缺血再灌注(I/R)诱导大鼠心肌细胞凋亡的作用机制。通过构建糖尿病I/R大鼠模型,再将大鼠随机分为4组(n=10):假手术组(Sham)、糖尿病I/R组(I/R)、I/R+10 mg/kg当归多糖组(I/R+ANG)、I/R+10 mg/kg当归多糖+15μg/kg阿柏西普组(I/R+ANG+AF);通过TTC染色法分析不同实验组大鼠心肌梗死面积差异;使用ELISA试剂盒分析当归多糖干预对I/R大鼠心肌酶水平和氧化应激反应的影响;借助TUNEL/DAPI双重染色分析各组大鼠心肌细胞凋亡情况;通过Western blotting检测当归多糖对血管内皮生长因子A (VEGFA)蛋白表达的影响。TTC染色检测结果表明,与糖尿病I/R组相比,当归多糖可显著减少糖尿病I/R大鼠心肌梗塞面积(p<0.05)。ELISA检测结果显示,与I/R组相比,当归多糖显著降低了糖尿病I/R组大鼠心肌酶--LDH和CK血清水平(p<0.05),并降低TNF-α(p<0.05)、IL-6 (p<0.05)水平,以及上调SOD活性(p<0.05)。TUNEL/DAPI双重染色镜检观察到当归多糖组的TUNEL阳性心肌细胞百分比显著低于I/R组(p<0.05);蛋白免疫印迹分析表明,与假手术组相比,在糖尿病I/R大鼠中检测到p-eNOS蛋白表达下调;而与I/R相比,当归多糖显著减轻了I/R对p-eNOS蛋白表达的抑制作用;与I/R组和阿柏西普组相比,当归多糖处理组的Caspase-3活化水平较低(p<0.05)。而VEGF抑制剂--阿柏西普处理均明显减轻上述当归多糖在糖尿病I/R大鼠中的所有有益作用。当归多糖通过减轻糖尿病I/R大鼠的氧化应激以及炎症反应,以及上调VEGFA表达和抑制Caspase-3活化来减弱糖尿病缺血/再灌注诱导的心肌细胞凋亡,从而在大鼠体内发挥心脏保护作用。

Angelica Polysaccharides Inhibit Apoptosis by Up-regulating VEGF

The aim of this study was to investigate the molecular mechanism of angelica polysaccharides in reducing myocardial cell apoptosis induced by diabetic ischemia-reperfusion(I/R). A rat model of diabetes I/R was constructed. The rats were randomly divided into 4 groups(n=10): Sham operation group(Sham), diabetic I/R group(I/R), I/R+10 mg/kg angelica polysaccharide group(I/R+ANG), I/R+10 mg/kg angelica polysaccharide+15 μg/kg aflibercept group(I/R+ANG+AF). The difference of myocardial infarction area in different experimental groups was analyzed by TTC staining. Different ELISA kits were used to analyze the effect of angelica polysaccharide intervention on myocardial enzyme levels and oxidative stress in I/R rats. TUNEL/DAPI dual staining was used to analyze the myocardial cell apoptosis rats in each group. The effect of Angelica sinensis polysaccharide on the expression of vascular endothelial growth factor A(VEGFA) protein was detected by Western blotting. TTC staining test results showed that compared with the diabetic I/R group, Angelica polysaccharide could significantly reduce the area of myocardial infarction in diabetic I/R rats(p<0.05). ELISA test results showed that angelica polysaccharide intervention significantly reduced myocardial enzymes-LDH and CK serum levels in diabetic I/R rats(p<0.05).And it restores myocardial oxidative stress and inflammation to improve cardiac function in diabetic I/R rats, by reducing the expression levels of TNF-α, MDA, and up-regulating the activity of SOD(p<0.05). TUNEL/DAPI double staining microscopy showed that the percentage of TUNEL-positive cardiomyocytes in Angelica polysaccharide group was significantly lower than that in I/R group(p<0.05). Western blotting analysis showed that compared with the sham operation group, p-e NOS protein expression was detected in diabetic I/R rats Down-regulated;Angelica polysaccharide significantly reduced the inhibitory effect of I/R on p-eNOS protein expression compared with I/R;compared with I/R group and aflibercept group, the activation level of caspase-3 in angelica polysaccharide treated group was lower(p<0.05). The treatment with VEGF inhibitor aflibercept significantly alleviated all the beneficial effects of the aforementioned angelica polysaccharide in diabetic I/R rats. Angelica polysaccharides reduce myocardial cell apoptosis induced by diabetic ischemia/reperfusion by reducing oxidative stress and inflammatory response, and up-regulating VEGFA expression and inhibiting caspase-3 a ctivation in diabetic I/R rats. Thus play a cardioprotective effect.