Department of Biochemistry and Biotechnology, Annamalai University, Annamalai Nagar 608002, Tamil Nadu, India.
Food Chem Toxicol. 2013 Mar;53:409-16. doi: 10.1016/j.fct.2012.12.010. Epub 2012 Dec 20.
Cardiac mitochondrial damage plays an important role in the pathology of myocardial infarction. The protective effects of (-) epicatechin on cardiac mitochondrial damage in isoproterenol induced myocardial infarction were evaluated in rats. Rats were pretreated with (-) epicatechin (20 mg/kg body weight) daily for a period of 21 days. After the pretreatment period, isoproterenol (100 mg/kg body weight) was injected subcutaneously into rats twice at an interval of 24 h to induce myocardial infarction. Isoproterenol induced myocardial infarcted rats showed a significant increase in the levels of cardiac diagnostic markers, heart mitochondrial lipid peroxidation, calcium, and a significant decrease in the activities/levels of heart mitochondrial glutathione peroxidase, glutathione reductase, reduced glutathione, isocitrate, succinate, malate, α-ketoglutarate and NADH-dehydrogenases, cytochrome-C-oxidase and adenosine triphosphate. (-) Epicatechin pretreatment showed significant protective effects on all the biochemical parameters evaluated. The in vitro study revealed the superoxide and hydroxyl radical scavenging activity of (-) epicatechin. The possible mechanisms for the beneficial effects of (-) epicatechin on cardiac mitochondria could be attributed to scavenging of free radicals, decreasing calcium, increasing multi-enzymes (antioxidant, tricarboxylic acid cycle and respiratory chain enzymes), reduced glutathione and adenosine triphosphate. Thus, (-) epicatechin attenuated mitochondrial damage in isoproterenol induced myocardial infarcted rats.
心脏线粒体损伤在心肌梗死的病理过程中起着重要作用。本研究旨在评估(-)表儿茶素对异丙肾上腺素诱导的心肌梗死大鼠心脏线粒体损伤的保护作用。大鼠预先用(-)表儿茶素(20mg/kg 体重)处理 21 天。预处理期结束后,每隔 24 小时给大鼠皮下注射异丙肾上腺素(100mg/kg 体重)两次,以诱导心肌梗死。异丙肾上腺素诱导的心肌梗死大鼠心脏诊断标志物水平显著升高,心脏线粒体脂质过氧化、钙水平显著升高,而心脏线粒体谷胱甘肽过氧化物酶、谷胱甘肽还原酶、还原型谷胱甘肽、异柠檬酸、琥珀酸、苹果酸、α-酮戊二酸和 NADH 脱氢酶、细胞色素 C 氧化酶和三磷酸腺苷的活性/水平显著降低。(-)表儿茶素预处理对所有评估的生化参数均显示出显著的保护作用。体外研究显示(-)表儿茶素具有清除超氧阴离子和羟自由基的活性。(-)表儿茶素对心脏线粒体有益作用的可能机制可归因于自由基清除、钙减少、多种酶(抗氧化剂、三羧酸循环和呼吸链酶)、还原型谷胱甘肽和三磷酸腺苷增加。因此,(-)表儿茶素减轻了异丙肾上腺素诱导的心肌梗死大鼠的线粒体损伤。