头顶一颗珠提取液对实验性糖尿病大鼠心肌损伤的干预作用

目的：探讨头顶一颗珠提取液（TTM）对糖尿病大鼠心肌损伤的干预作用及机制，为进一步研究头顶一颗珠的药理作用提供理论基础。方法：雄性SPF级SD大鼠48只，随机分为4组（n=12）正常对照组、模型组、干预组、及阳性对照组，采用高脂饮食加一次性尾静脉注射STZ 35 mg/kg复制糖尿病模型。干预组在实验开始时给予TTM浓度1 mg/ml头顶一颗珠提取液3 ml灌胃，每天1次；造模成功后阳性对照组用二甲双胍5mg/kg.d灌胃治疗，各组继续喂养6周，处死大鼠，取血测B型脑钠肽（BNP）、心肌肌钙蛋白I（cTnI）水平，心脏称重计算心脏重量指数（心重/体重），TUNEL法计算心肌细胞凋亡指数，取心室肌组织行常规形态学及Masson染色观察，检测心肌组织SOD， GPx，MDA水平。结果：TTM干预可明显降低糖尿病大鼠心脏重量，降低血清中BNP、cTnI水平，提高心肌组织中SOD， GPx活性，降低MDA含量，抑制心肌细胞凋亡，而且在增强GPx活性、抑制胶原纤维产生方面，TTM作用比西药二甲双胍效果更好。结论：头顶一颗珠提取物可能通过减轻糖尿病大鼠体内氧化应激反应，进而抑制心肌细胞凋亡，减少胶原纤维产生，来达到保护心肌细胞损伤的作用。

Intervention effect of trillium tschonoskii maxim extract solution on myocardial injury in diabetic rats

Objective: To study the protective effect and the underlying mechanism of trillium tschonoskii maxim (TTM, Traditional Chinese Medicine) on myocardial injury of diabetic rats induced by high-fat diet and streptozotocin (STZ), which will lay a theoretical foundation for further exploring its pharmacological effect. Methods: SD male rats received high fat diet and STZ (35 mg/kg) via tail vein injection were modeled into diabetic rats, the levels of brain natriuretic peptide (BNP) and cardiac troponin I (cTnI) in serum, the contents of superoxide (SOD), glutathione peroxidase (GPX),malondialdehyde (MDA) in cardiac tissues, and cardiac myocyte apoptosis index were tested in all groups after the last administration. Results: Compared with that in the model group, SOD and GPX activities were significantly increased and levels of BNP、cTnI、cardiac weight index (CWI)、apoptosis index (AI) were decreased in TTM and metformin (Met) group. The effects of TTM were better than traditional medicine metformin in enhancing GPX activity and decreasing collagen level. Conclusion: TTM can inhibit myocardial apoptosis by reducing oxidative stress responses in diabetic rats, which can slow down collagen fiber production to protect the myocardial cell injury.