虾青素对急性心梗大鼠心肌细胞凋亡及caspase-3表达的影响

Effects of astaxanthin on apoptosis and caspase-3 expression of myocardial cells in rats with acute myocardial infarction

目的探讨虾青素(astaxanthin,AST)对急性心梗大鼠心肌细胞凋亡以及caspase-3表达的影响。方法雄性6-8周SD大鼠25只随机分为假手术组(n=5)、心梗组(n=10)、虾青素组(n=10)。心梗组和虾青素组通过结扎冠状动脉建立心梗模型(myocardial infarction,MI),随后虾青素组灌胃给予虾青素[5 mg/(kg·d)],心梗组和假手术组灌胃给予等量生理盐水。在制备心梗模型的第3天进行HE染色检测心肌细胞病理变化,TUNEL法检测心梗后心肌细胞凋亡指数,Western blot法检测大鼠心肌梗死周边区活化的caspase-3含量。结果与假手术组相比,心梗组心肌细胞排列紊乱,心肌纤维断裂伴有大量的炎性细胞浸润。心梗组心肌细胞凋亡指数较假手术组明显增加[(69.53±14.87)%vs(1.17±0.60)%,P<0.05],心梗组梗死周边区活化的caspase-3含量较假手术组增高(0.09±0.02 vs 0.70±0.06,P<0.05)。与心梗组大鼠相比,虾青素组大鼠心肌细胞变性程度及炎性细胞浸润程度均有所减轻。虾青素组心肌细胞凋亡指数较心梗组降低[(11.98±5.58)%vs(69.53±14.87)%,P<0.05],虾青素组梗死周边区活化的caspase-3含量较心梗组降低(0.29±0.09 vs 0.70±0.06,P<0.05)。结论虾青素可以减轻大鼠急性心肌梗死后的心肌细胞凋亡,保护心梗大鼠的心肌细胞。

Objective To explore the effects of astaxanthin on apoptosis of myocardial cells and the expression of caspase-3 in acute myocardial infarction(MI).Methods Male(6-8 weeks old)SD rats were randomly divided into sham group(n=5),MI group(n=10)and AST group(n=10).The myocardial infarction model in MI group and AST group was established by ligation of the coronary artery.Subsequently,the rats were given astaxanthin[5 mg/(kg·d)]in AST group,and the same amount of physiological saline in MI group and sham group.The pathologic changes of myocardial cells were detected by HE staining 3 d after the myocardial infarction.TUNEL method was used to detect the apoptosis of myocardial infarction cells.Western blot method was used to detect the activation of caspase-3 in the peripheral area of myocardial infarction in rats.Results Compared with sham group,myocardial cells were disordered in MI group,and the myocardial fibrillation was accompanied by a large number of inflammatory cell infiltration.The apoptotic index of myocardial cells was significantly higher in MI group than that in sham group[(69.53±14.87)%vs(1.17±0.60)%,P<0.05],and the content of cleaved caspase-3 in the peripheral infarction area was higher than that in sham group(0.09±0.02 vs 0.70±0.06,P<0.05).Compared with MI group,the degree of myocardial cell degeneration and inflammatory cell infiltration were all reduced in astaxanthin group.The apoptotic index of myocardial cells was decreased in astaxanthin group compared with MI group[(11.98±5.58)%vs(69.53±14.87)%,P<0.05],and the content of cleaved caspase-3 in the peripheral infarction area was also decreased(0.29±0.09 vs 0.70±0.06,P<0.05).Conclusion Astaxanthin can reduce the cardiomyocyte apoptosis after acute myocardial infarction in rats and protect myocardial cells in infarcted rats.