健胰方通过调控胰高血糖素样肽-1表达改善糖尿病大鼠胰岛细胞功能的研究

Preliminary Study on Jianyi Recipe in Improving Islet Cell Function in Diabetic Rats Through Regulation of Glucagon-like Peptide-1 Expression

【目的】从胰高血糖素样肽-1(GLP-1)合成、分泌和灭活3个环节探索健胰方影响GLP-1改善胰岛细胞功能的可能机制。【方法】采用高脂饲料联合链脲佐菌素(STZ)法诱导糖尿病模型大鼠,随机分为模型组、复方组与正常组,干预4周。快速血糖仪测定血糖,Luminex液相蛋白芯片技术测定血浆GLP-1和胰岛素(insulin)水平,实时荧光定量PCR检测胰腺组织胰岛—十二指肠同源盒基因-1(PDX-1)m RNA表达,免疫组织化学法检测回肠L细胞合成GLP-1,酶联免疫法检测Ⅳ型二肽基肽酶(DPP-Ⅳ)。【结果】健胰方可显著降低糖尿病模型大鼠的空腹及糖负荷后血糖水平(P<0.05),促进糖尿病大鼠血中胰岛素的分泌(P<0.05),提高胰腺PDX-1 m RNA表达(P<0.05),提高血浆GLP-1水平与回肠组织GLP-1阳性反应面积及累积光密度值(P<0.05);但血清DPP-Ⅳ各组间比较无显著性差异(P>0.05)。【结论】健胰方可能是通过调控GLP-1的合成与分泌,从而促进PDX-1基因表达和胰岛素分泌以降低糖尿病大鼠血糖水平的。

Objective To explore the possible mechanism of Jianyi Recipe for improving the function of islet cells from the aspects of synthesis, secretion and inactivation of glucagon-like peptide-1（GLP-1 ）. Methods The diabetic rat model was established by feeding with high-lipid food combined with injection of streptozotocin （STZ）. The rats were randomly divided into model group, Jianyi Recipe group, and normal group. The treatment for the rats lasted for 4 weeks. The blood glucose level was detected by the rapid blood glucose meter. The plasma levels of GLP-1 and insulin were detected by Luminex liquid phase protein chip technology. Pancreatic duodenal homeobox-1 （PDX-1） mRNA expression level was detected by quantitative real-time fluorescence polymerase chain reaction （PCR）. The level of GLP-1 in ileum L cells was detected by immunohistochemistry, and dipeptidyl peptidase Ⅳ （DPP-Ⅳ） level was detected by enzyme-linked immunosorbent assay. Results Jianyi Recipe could decrease the levels of fasting blood glucose and postprandial glucose （P 〈 0.05） , promote the secretion of insulin （P 〈 0.05） , and increase PDX-Ⅰ mRNA expression level in the pancreas of the diabetic rats. Compared with the model group, plasma GLP-1 level, and ileal GLP-1 positive expression area and integrated optical density were increased （P 〈 0.05） in Jiauyi Recipe group, while the differences of serum DPP-Ⅳ levels were insignificant between the two groups （P〉 0.05）. Conclusion Jianyi Recipe maybe regulate the synthesis and secretion of GLP-1 to promote PDX-1 gent expression and insulin secretion, so as to reduce blood glucose in diabetic rats.