降糖三黄片抑制糖尿病小鼠胰岛细胞的内质网应激和自噬

目的 探讨降糖三黄片对db/db小鼠血糖调节和胰岛细胞损伤的影响以及糖脂毒性诱导的胰岛细胞内质网应激和自噬初期的保护机制。方法 40只db/db小鼠随机分为db/db、db/db+JT(L)(1.32 g/kg)、db/db+JT(H)(2.64 g/kg)、db/db+Met(0.225 g/kg)，以C57BL/6J小鼠为正常组（n=10）。干预8周，检测血糖血脂等代谢指标，观察胰岛细胞形态变化。体外培养小鼠胰岛细胞（MIN6），将其分为4组：Control组（5 mmol/L葡萄糖），HH组（22 mmol/L葡萄糖+0.1 mmol/L棕榈酸），HH+JT组（高脂高糖组条件基础上+5%降糖三黄片含药血清）和HH+JT+SP600125组（降糖三黄片组条件基础上+20μmol/lSP600125）。流式术检测MIN6凋亡，RT-qPCR和Western blot检测内质网应激与自噬初期水平。结果 与对照组相比，中药有效改善糖脂代谢水平（P<0.05），延缓体质量持续增长（P<0.05），但对饮水量改善效果不明显（P>0.05）。HE染色发现降糖三黄片可修复胰岛细...

Jiangtang Sanhuang tablet inhibits endoplasmic reticulum stress and autophagy in diabetic mouse islet cells

Objective To investigate effects of Jiangtang Sanhuang tablet (JTSHT) for regulating blood glucose and alleviating islet cell damage in db/db mice and its protective effects against endoplasmic reticulum stress (ERS) and autophagy induced by glycolipid toxicity. Methods Forty db/db mice were randomized into 4 groups for daily intragastric administration of saline, JTSHT of 2.64 and 1.32 g/kg, and metformin at 0.225g/kg for 8 weeks, using 10 C57BL/6J mice as the normal control. After the treatments, the metabolic indexes of the mice were measured, and morphological changes of the islet cells were observed. A mouse islet cell line (MIN6) was exposed to high glucose (22 mmol/L glucose) and 0.1 mmol/L palmitic acid, followed by treatment with the sera from JTSHT- or saline- treated SD rats, alone or in combination with SP600125, and the changes in cell apoptosis, ERS and autophagy were evaluated using flow cytometry, RT-qPCR and Western blotting. Results In db/db mice, treatment with JTSHT significantly improved glucose and lipid metabolism (P<0.05) and suppressed progressive weight gain (P<0.05) without significant effect on drinking water volume (P>0.05). JTSHT was also found to promote repair of islet cell injuries. In the cell experiments, high glucose exposure significantly increased apoptosis rate of MIN6 cells (P<0.05), which was obviously lowered by treatment with JTSHT-treated rat serum (P<0.05). Western blotting showed that JTSHT significantly reduced the level of ERS and autophagy caused by glycolipid toxicity in MIN6 cells (P<0.05). Interference with ERS using SP600125 significantly attenuated the protective effect of JTSHT against MIN6 cell injury, apoptosis and autophagy induced by glycolipid toxicity (P<0.05). Conclusion JTSHT has protective effects against glycolipid toxicity in MIN6 cells possibly by inhibiting ERS and autophagy.