摘要
目的:探讨小檗碱保护棕榈酸诱导的胰岛βTC3细胞的可能机制,观察PTEN是否参与该过程,以及小檗碱对胰岛素分泌的影响。方法:用1.0 mmol/L棕榈酸制作胰岛βTC3细胞脂毒性损伤模型,给予小檗碱干预;放射免疫法检测胰岛素分泌,West-ern blot法进行PTEN、p-AKT、AKT、Bcl-2、Bax、活性Caspase3蛋白的检测。实验分3大组(对照组、棕榈酸组、棕榈酸+小檗碱治疗组),棕榈酸分别作用3个时间段(24、48、72 h)。结果:(1)放射免疫法胰岛素分泌测定结果显示:β细胞暴露于棕榈酸24 h后,5.6、16.7 mmol/L葡萄糖刺激的胰岛素分泌均较正常对照组显著减少(P<0.01);添加小檗碱干预后胰岛素分泌较棕榈酸组回升,但较对照组减少(P均<0.01)。(2)在棕榈酸处理的3个时间段内,与对照组相比,棕榈酸组的PTEN、Bax、Active-Caspase3蛋白表达水平显著升高,p-AKT、Bcl-2蛋白水平下降;小檗碱干预后PTEN、Bax蛋白表达水平下降,p-AKT、Bcl-2蛋白水平提高(P均<0.01)。结论:小檗碱可改善棕榈酸引起的胰岛素分泌减少,抑制脂毒性诱导的PTEN表达增加,减少促凋亡基因Bax、Active-Caspase3表达,并增加抑凋亡基因Bcl-2基因表达及AKT的活化,从而拮抗棕榈酸诱导的β细胞凋亡,保护β细胞功能。
Objective： To evaluate the protective effect of berberine on pancreatic βTC3 cells lipoapoptosis induced by free fatty acids, investigated the role of PTEN/AKT signaling in berberine involved beta cell protection. To explore the anti-diabetic effects of berberine and its influence on inslin secretion. Methods： The basal and glucose stimulated insulin secretion capability of βTC3 cells were evaluated when exposed to FFAs with or without berberine by Radioimmunoassay. The expression of PTEN, AKT, p-AKT and apoptosis related proteins Bax, Bcl-2 and Active-Caspase3 were detected by western blotting in βTC3 cells when exposed to FFAs with or without berberine. Results： Berberine substantially facilitated the basal and glucose stimulated insulin secretion of beta cells in high FFAs condition. Western blot revealed that the phosphorylation of AKT and Bcl-2 was markedly decreased under lipid stress but was elevated when treated with berberine. Moreover, FFAs could up-regulate the expression levels of PTEN, Bax, and Active-Caspase3, but down-regulate the expression levels of p-AKT and Bcl-2 in beta cells, which were canceled by the addition of berberine. Conclusions：Berberine observably inhibited the apoptosis, elevated proliferation and the basal and glucose stimulated insulin secretion of beta cells in high FFAs condition. Furthermore, the protective action of berberine was probability mediated by activation of PTEN/AKT, which was accompanied by the down-regulation of Bax, Active-Caspase3 and up-regulation of p-AKT and Bcl-2 expressions.
出处
《现代生物医学进展》
CAS
2017年第5期810-814,共5页
Progress in Modern Biomedicine
基金
国家自然科学基金项目(81573746)
陕西省卫计委2014课题(2014D67)
