龙眼叶乙酸乙酯提取物对2型糖尿病大鼠降血糖作用机制的研究

Study on hypoglycemic mechanism of ethylacetate extracts from the leaves of Longan Arillus in type 2 diabetes mellitus rats

目的:研究龙眼叶乙酸乙酯提取物(简称龙眼叶提取物)对2型糖尿病大鼠降血糖作用机制。方法:采用高糖高脂饲料结合腹腔注射链脲佐菌素(STZ)制备2型糖尿病大鼠模型,以二甲双胍为阳性对照,考察龙眼叶提取物对2型糖尿病大鼠体质量、空腹血糖(FBG)、糖耐量(OGTT)、胸腺指数、胰岛素浓度(FINS)、超氧化物歧化酶(SOD)、丙二醛(MDA)、总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、肿瘤坏死因子-α(TNF-α)、白细胞介素6(IL-6)及胰腺病理形态的影响。结果:龙眼叶提取物能显著降低糖尿病大鼠的血糖,增强其葡萄糖耐受能力,并能提高糖尿病大鼠的IRI,同时对糖尿病大鼠有升高SOD活性、降低MDA含量的作用,抑制其胸腺萎缩。并能调节糖尿病大鼠的血脂紊乱情况,降低大鼠血清中TNF-α和IL-6的分泌。对糖尿病大鼠的胰腺病理形态特征也有一定的改善。结论:龙眼叶提取物对2型糖尿病大鼠有降血糖作用,其作用机制可能与修复胰岛细胞损伤、降低炎性反应因子水平及抗脂质过氧化过程有关。

Objective: To investigate the hypoglycemic mechanism of ethyl acetate extracts from the leaves of Longan Arillus in type 2 diabetes mellitus rats. Methods: The model of type 2 diabetes mellitus rats were established by high glucose and high fat diet combined with STZ, metformin as a positive control, the effects of ethyl acetate extracts from the leaves of Longan Arillus on the body weight change of rats, fasted blood glucose(FBG), glucose tolerance(OGTT), thymus index, concentration of insulin(FINS), activity of SOD, amount of MDA, total cholesterol(TC), triglyceride(TG), high-density lipoprotein cholesterol(HDL-C), low density lipoprotein cholesterol(LDL-C), tumor necrosis factor-α(TNF-α), interleukin 6(IL-6) and the pancreas pathological morphology were observed. Results: The ethyl acetate extracts of the leaves of Longan Arillus. could significantly decrease fasted blood glucose and improve glucose tolerance in diabetic rats. It could increase the level of serum insulin and insulin sensitivity of the model rats. At the same time, activity of SOD was obviously increased, and amount of MDA was obviously decreased, and it could suppress thymic atrophy. It could modulate the blood lipid disorder and reduce the level of TNF-α and IL-6 inflammatory factors in serum of rats. And the pathological morphological features of the pancreas were also improved. Conclusion: The ethyl acetate extracts of the leaves of Longan Arillus are showed significant hypoglycemic effect on the type 2 diabetes mellitus rats. The mechanism of hypoglycemic action maybe related with accelerating the repair of pancreatic cells injured, inhibiting the secretion of inflammatory factors, and process of anti-lipid peroxidation.