半夏泻心汤调节2型糖尿病人GLP-1和β细胞功能的分子机制

Incretin, dysfunction of pancreatic islet beta cell, and intestinal flora imbalance are all hot topics in the etiology of type 2 diabetes, while the method of modulating gastrointestine has been the traditional therapy for diabetes in TCM. On the basis of previous research, this study, with newly diagnosed type 2 diabetes patients with syndrome of disorder of stomach qi as subjects, which were randomly divided into four groups, i.e. Ban-Xia-Xie-Xin-Tang decoction(BXXXT) group, the GLP-1 analogue group, Glimepiride group and the placebo group, and with dynamic acquisition of plasma and serum in the day of initially enlisting, 4th week, 8th week, and 16th weeks, to detect indices such as GLP-1, Fins, HOMA IR, Resistin, etc., was designed to confirm that BXXXT can elevate GLP-1 levels and increase the amount of islet beta cells in the patients, so as to achieve the purpose of lowering blood sugar. By detection of key indicators reflecting human intestinal flora in type 2 diabetes, such as plasma lipopolysaccharide, etc., this study confirmed that the therapeutic effect of elevating GLP-1 levels of BXXXT is achieved by regulating intestinal flora. At the same time, by detecting the apoptosis of human islet beta cells, this study also confirmed that the effects of BXXXT in elevating GLP-1 and anti-apoptosis are by modulating the expression of apoptosis protein Caspase -3 and antiapoptotic factor BCL-2.

肠促胰岛素和胰岛β细胞功能紊乱，以及肠道菌群失调是2型糖尿病病因学新热点，而调和胃肠法一直是中医治疗糖尿病的传统法则。本研究在前期研究的基础上，以2型糖尿病人为研究对象，将符合胃气不和证患者随机分为半夏泻心汤（BXXXT）组、GLP-1类似物组、格列美脲组和安慰剂组，于入组、4周、8周、16周，动态采集血浆和血清，检测GLP-1、Fins、HOMA-IR、Resistin等指标，证实BXXXT能提高患者体内GLP-1水平，增加胰岛β细胞量，从而达到降低血糖的目的。检测血浆脂多糖等反应人类2型糖尿病肠道菌群因素的关键指标，证明BXXXT提高血浆GLP-1水平是通过调节肠道菌群实现的。同时进行BXXXT对人胰岛β细胞凋亡的研究，通过凋亡蛋白Caspase-3及抗凋亡因子bcl-2的表达，证实其提高GLP-1、抗凋亡的作用。

胰岛B细胞功能障碍和胰岛β细胞凋亡是2型糖尿病发生的重要机制之一。许多中医学者认为脾虚胃热、痰瘀互结，胃肠失调是导致糖尿病发生发展的重要病机。调和胃肠法能够改善胃肠道功能、健脾清热、祛瘀化痰。近年来多项文献报导证明半夏泻心汤改善糖尿病的症状体征和实验室检查的临床疗效较好。. 本实验在前人研究的基础上探索半夏泻心汤对胰岛β细胞凋亡的影响，初步发现（1）TBHP的适宜造模浓度为400µm干预4h；（2）半夏泻心汤预处理浓度为0.25 mg/ml，0.5 mg/ml，1 mg/ml，最佳预处理时间为12h。（3）MTT、TUNEL和Hoechst 33342染色结果表明半夏泻心汤能够抑制MIN6细胞的凋亡、减轻细胞核凝聚和减少细胞碎片。（4）半夏泻心汤可减轻TBHP诱导的MIN6细胞氧化应激的影响，增强细胞的抗氧化性能。（5）半夏泻心汤能够调节PI3K/AKT/FOXO1通路蛋白的表达。本研究证实了半夏泻心汤可改善MIN6细胞凋亡，其可能是通过减轻TBHP诱导的MIN6细胞的氧化应激及激活PI3K/AKT/FOXO1通路，从而调节下游因子表达有关。. 本研究在临床研究方面初步发现：半夏泻心汤能降低初诊2型糖尿病患者血糖、GLU、胃动素、胃泌素、脂多糖结合蛋白的水平，升高胰岛素、C肽、GLP-1、生长抑素的水平，改善胃肠道激素分泌、胰岛功能和糖脂代谢功能。治疗前2型糖尿病人GLP-1、HOMA-ß、胰岛素、C肽、生长抑素均低于正常人，血糖、GLU、胃动素、胃泌素、脂多糖结合蛋白均高于正常人；经过12周治疗后，GLP-1、HOMA-ß、胰岛素、C肽、生长抑素均有所增加，血糖、GLU、胃动素、胃泌素、脂多糖结合蛋白均有所下降。