基于HMGB1/TLR4途径评价通络消渴方对糖尿病大鼠心脏的保护作用

Evaluation on cardioprotective effects of Tongluo Xiaoke Formula on diabetic rats based on HMGB1/TLR4 pathway

目的:通过研究HMGB1/TLR4信号通路变化,探索通络消渴方改善2型糖尿病大鼠心脏损伤的可能机制。方法:采用链脲佐菌素(STZ)腹腔注射方法建立2型糖尿病大鼠模型,成模后将大鼠随机分为模型组、二甲双胍组及通络消渴方高、低剂量组,并设正常对照组。造模成功后即开始灌胃给药,中药高剂量组(7.36 g·kg^(-1)·d^(-1))、中药低剂量组(1.84 g·kg^(-1)·d^(-1))和二甲双胍组(140 mg·kg^(-1)·d^(-1)),空白组和模型组灌胃同体积0.9%NaCl溶液,每日1次。8周后处死大鼠,取样检测各组大鼠空腹血糖、心肌病理及HMGB1和TLR4蛋白表达。结果:与正常对照组比较,模型组大鼠血糖显著升高、体质量明显下降;与模型组比较,通络消渴方高、低剂量组均可抑制大鼠血糖升高,且中药高剂量组可明显抑制体质量下降,差异具有显著性(P<0.05)。病理结果显示,通络消渴方高、低剂量组和二甲双胍组大鼠心肌病理改变较糖尿病模型组明显减轻;免疫组化结果显示,通络消渴方高剂量组、低剂量组和二甲双胍组均可降低大鼠HMGB1和TLR4蛋白表达,与模型组比较差异有统计学意义(P<0.05)。结论:通络消渴方可改善糖尿病大鼠心脏功能,其机制可能与降低HMGB1/TLR4信号蛋白表达,从而发挥抗炎作用有关。

Objective： To explore the possible mechanisms of Tongluo Xiaoke Formula on improving cardiac injury in type 2 diabetic rats through the changes in HMGB1/TLR4 signaling pathway. Methods： The rat model of type 2 diabetes rats was established by intraperitoneal injection of streptozoosin（ STZ）. After successfully modeling,the rats were randomly divided into the model group,metformin group and Tongluo Xiaoke Formula groups with high-and low-dose,and the normal rats were taken as the normal control group. The rats were treated with the corresponding drugs by intragastric administration once a day. The Chinese medicine groups with high-and low-dose were treated with decoction of Tongluo Xiaoke Formula at dose of 7. 36 g · kg^-1·d^-1 and 1. 84 g · kg^-1·d^-1 respectively,the metformin group was treated with metformin at dose of 140 mg·kg^-1·d^-1,and the blank group and model group were treated with 0.9% NaCl solution at equivalent volume. 8 weeks later,the rats were sacrificed and the samples were collected. The fasting blood glucose,myocardial pathology and expressions of high mobility group box-1（ HMGB1） protein and Toll-like receptor 4（ TLR4） in each group were detected. Results： Compared with the normal control group,the blood glucose in the model group was increased significantly and the body weight was decreased significantly. Compared with the model group,the increased blood glucose was inhibited in the Chinese medicine groups with high-and low-dose,and the decreased body weight was suppressed in the Chinese medicine group with high-dose,with statistically significant differences（ P〈0.05）. The pathological results showed that the pathological changes on myocardium in the metformin group and Tongluo Xiaoke Formula groups with high-and low-dose were obviously alleviated compared with the model group. The immunohistochemical results showed that compared with the model group,the protein expressions of HMGB1 and TLR4 were decreased in the metformin group and Tongluo Xiaoke Formula groups with high-and low-dose,with statistically significant differences（ P〈0.05）. Conclusion： Tongluo Xiaoke Formula can improve the cardiac function of diabetic rats,and its mechanism may be related to the down-regulation of HMGB1/TLR4 signaling protein expressions,which plays the anti-inflammatory effects.