2型糖尿病模型大鼠胰岛β细胞损伤和益气养阴化痰祛瘀方的保护作用及机制

Protective effect and its underlying mechanism of the formula for tonifying qi and nourishing yin with activating blood and dissipating phlegm on islet β cell damage in type 2 diabetes rat model

为探查2型糖尿病中医证候模型大鼠(Rattus norvegicus)胰岛细胞损伤机制和中医因证治方的保护作用,采用雄性SD大鼠给予高脂高糖联合小剂量链脲佐菌素(STZ,30 mg/kg)注射的方法复制2型糖尿病气阴二虚痰瘀证模型.将成模后4周的大鼠分为模型组、西药组(盐酸吡格列酮)和中药组(益气养阴化痰祛瘀方),给药组连续灌胃干预2周,正常组和模型组均给予等量生理盐水.检测空腹血糖(FPG)、血清胰岛素(Fins)、血清胰岛素原(PI)、甘油三酯(TG)、高密度脂蛋白(HDL-c)、游离脂肪酸(FFA)、低密度脂蛋白(LDL-c),测定胰腺组织一氧化氮合酶(i NOS)、核因子(NF-?B)、超氧化物歧化酶(SOD)、血管内皮生长因子(VEGF)、肝细胞生长因子(HGF)、非受体酪氨酸激酶2(JAK-2)、蛋白激酶B(PKB)、胰淀素(amylin),观测胰脏胰岛病理及细胞面积.结果发现,模型组大鼠的FPG,血清Fins,PI,TG,FFA,LDL-c以及胰腺i NOS,NF-?B和Amylin含量升高(P<0.01或P<0.05),血清HDL-c和胰腺SOD,VEGF,HGF,JAK-2,PKB含量明显降低(P<0.01或P<0.05),胰腺的胰岛明显萎缩,结构紊乱,胰岛内可见空泡样变,细胞比积下降;益气养阴化痰祛瘀方组大鼠的FPG,血清Fins,PI,TG,LDL-c以及胰腺组织i NOS和Amylin的含量下降(P<0.01或P<0.05),胰腺SOD,VEGF,HGF,JAK-2,PKB的含量升高(P<0.01或P<0.05),胰岛结构基本正常,边界较清晰,空泡样变细胞明显减少,细胞所占面积增加.研究表明,该模型大鼠出现2型糖尿病及脂质代谢异常并伴有明显的胰岛损伤;益气养阴化痰祛瘀方在改善模型糖脂代谢的同时,有改善胰岛病理损伤及促进胰岛再生的作用,其胰岛保护性作用机制可能涉及抗氧化应激损伤、促进胰腺内皮保护性因子生成及调节JAK-2/STAT-5和PI3K/PKB信号通路.

To study the type 2 diabetes with TCM syndrome rat＇s islet beta cell damage mechanism, and the protection of the formula designed aiming at given syndrome＇s treatment, in this research, the Male SD rats were given high fat and sugar in combination with small dose of STZ（30 mg/kg） to induce the type 2 diabetes model with Qi and yin deficiency, phlegm and blood stasis syndrome. After 4 weeks, the rats of diagnostic criteria for T2 DM were divided into model group, the western medicine（pioglitazone hydrochloride） group and Chinese medicine（formula for Supplementing qi and nourishing yin with activating blood and dissipating phlegm） group. The Chinese medicine group and western medicine group were administrated drugs for two weeks. Normal group was given saline solution. FPG, Fins, PI, serum TG, HDL-c, FFA, LDL-c in blood and i NOS, NF- KB, SOD, VEGF and HGF, JAK-2, PKB, Amylin in pancreatic tissue were detected. The pancreatic islet pathology were observed. The results showed that FPG, Fins, PI, TG, FFA, LDL-c, i NOS, NF-？B and Amylin content were significantly increased（P〈0.01 or P〈0.05）, HDL-c and SOD, VEGF and HGF, JAK-2, PKB content significantly decreased（P〈0.01 or P〈0.05）, and pancreas islet had obvious atrophy, structure disorder, vacuoles like cells, and beta cell area percentage declined in model group. Compared with model group, there were FPG, Fins, PI, serum TG, LDL-c and pancreatic i NOS and Amylin content decreased（P〈0.01 or P〈0.05） in Chinese medicine group. The pancreatic islet structure and the boundary were clear, vacuolar cells decreased, and beta cell area percentage increased. Furthermore pancreatic SOD, VEGF, HGF, JAK-2 and PKB markedly increased（P〈0.01 or P〈0.05）. So we can get conclusions that Type 2 Diabetes model had lipid metabolic abnormalities and obvious pancreas injury. Chinese medicine could improve the glucolipid metabolism and the pancreas pathological damage, and promote the regeneration of the islet cell. The mechanism may be related to against oxidative stress damage, promote the pancreas endothelial protective factors generated, and regulate the signal pathways of JAK-2/STAT-5 and PI3K/PKB.