铁苋菜叶提取物抑制大鼠实验性心肌缺血的生物化学和组织病理学研究(英文)

Effectiveness of flavonoid-rich leaf extract of Acalypha indica in reversing experimental myocardial ischemia: biochemical and histopathological evidence

目的:研究富含类黄酮的热带铁苋菜叶的甲醇提取物抗心肌缺血的作用。方法:用异丙肾上腺素诱导大鼠心肌缺血。成年Wistar白化大鼠经热带铁苋菜提取物(100和200mg/kg大鼠体质量,口服)30d预处理后连续2d注射异丙肾上腺素(85mg/kg大鼠体质量,皮下注射)。第2次注射异丙肾上腺素后12h,肌肉注射氯胺酮(24mg/kg大鼠体质量)处死大鼠。检测血浆总胆固醇、三酰甘油、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇、极低密度脂蛋白胆固醇、游离脂肪酸、磷脂质以及心肌脂质、肝脏脂质的含量,以衡量热带铁苋菜提取物的抗心肌缺血作用,同时观察大鼠心脏组织的组织病理学变化。结果:与模型组大鼠相比,所有热带铁苋菜提取物给药组(100和200mg/kg)大鼠的血浆脂质水平改善,且与正常组相比无明显变化。模型组大鼠心脏组织病理学结果显示心肌纤维缺失,广泛性心内膜下坏死,炎症细胞浸润,心肌细胞明显水肿,空泡变性。而经200mg/kg热带铁苋菜提取物预处理的大鼠心脏组织观察到较完整的心肌结构,心肌纤维可见,没有炎症细胞浸润、细胞水肿和坏死现象。结论:本研究的生化指标及组织学结果表明热带铁苋菜可抑制异丙肾上腺素诱导的大鼠心肌缺血。

OBJECTIVE：In this study,we investigated the antimyocardial ischemic effects of flavonoid-rich methanolic leaf extract of Acalyphaindica（AIE）. METHODS：An animal model of myocardial ischemic injury was induced by isoproterenol（ISO） in adult rats.Albino Wistar rats were pretreated with the AIE（100 and200 mg/kg body weight orally）for 30 d followed by ISO（85 mg/kg subcutaneously）at an interval of 24 h for 2 d.At the end of the experimental period（12 h after the second dose of ISO injection）,rats were sacrificed by anaesthetization with an intramuscular injection of ketamine hydrochloride（24 mg/kg）. To ensure anti-ischemic potential of AIE,the plasma lipids such as total cholesterol（TC）, triglycerides（TG）,high-density lipoprotein cholesterol（HDL-C）,low-density lipoprotein cholesterol（LDL-C）,very low-density lipoprotein cholesterol（VLDL-C）,free fatty acids （FFA）,phospholipids（PL）,myocardial lipids and hepatic lipids（TC,TG,FFA and PL）were estimated.Histopathology of heart tissue was also examined. RESULTS：Administration of AIE maintained the levels of plasma lipids in all the treatment groups（100 and200 mg/kg）when compared with the ISO-injected model rats.Histopathological examination of heart tissue of ISO-administered model rat showed myofiber loss,extensive subendocardial necrosis,infiltration of inflammatory cells,marked myocellular edema and vacuolar degeneration.However,pretreatment with AIE at 200 mg/kg showed predominantly normal myocardium structure with myofibers appeared and no inflammatory cell infiltration, edema and necrosis. CONCLUSION：The biochemical and histological evidence from this study shows that AIE is protective against ISO-induced myocardial ischemia.