硫氧还蛋白相互作用蛋白(thioredoxin interacting protein,TXNIP)是内源性硫氧还蛋白结合抑制蛋白,在糖尿病患者血清和组织中均高表达。本研究观察TXNIP过表达对正常糖脂浓度下培养的INS-1细胞自噬水平的影响,并分析自噬在TXNIP诱导的细胞凋亡中的作用。常规培养的INS-1胰岛细胞分为正常培养组、空病毒(Ad-eGFP)组和TXNIP过表达(Ad-TXNIP-eGFP)组,后两组转染相应腺病毒,48 h后测定TXNIP mRNA和蛋白的表达情况;用Western blot检测各组自噬相关的Beclin-1、LC3和P62的蛋白表达情况,以cleaved caspase 3/caspase 3比值和流式细胞术检测各组细胞凋亡情况;用IF/ICC法检测各组细胞内自噬体数量的变化。结果显示,与Ad-eGFP组相比,Ad-TXNIP-eGFP组TXNIP mRNA和蛋白表达量均明显升高;与Ad-eGFP组相比,Ad-TXNIP-eGFP组LC3-II/LC3-I比值和Beclin-1蛋白表达水平升高,P62蛋白表达降低,自噬体荧光强度增强,细胞凋亡率升高,cleaved caspase 3/caspase 3比值上升。使用自噬抑制剂3-MA干预后,与TXNIP过表达组相比,TXNIP过表达+3-MA组自噬明显受到抑制,同时凋亡明显减轻。以上结果提示,在正常糖脂浓度培养下的INS-1细胞过表达TXNIP可以通过诱导自噬促进细胞凋亡。 Thioredoxin interacting protein (TXNIP) is an endogenous thioredoxin binding inhibitor that is highly expressed in the serum and tissues of diabetic patients. This study was to investigate the effect of TXNIP overexpression on the autophagy of INS-1 cells cultured in normal glycolipid concentration and analyze the role of autophagy in TXNIP-induced apoptosis. The cultured INS-1 islet cells were divided into normal culture group, Ad-eGFP group and Ad-TXNIP-eGFP group. The latter two groups were transfected with the corresponding adenovirus. The expression of TXNIP mRNA Western blot was used to detect the protein expression of autophagy-related Beclin-1, LC3 and P62 in each group. The apoptosis rate of each group was detected by cleaved caspase 3 / caspase 3 ratio and flow cytometry. IF / ICC method was used to detect the number of intracellular autophagosomes in each group. The results showed that compared with Ad-eGFP group, TXNIP mRNA and protein expression in Ad-TXNIP-eGFP group were significantly increased; compared with Ad-eGFP group, LC3-II / LC3-I ratio And Beclin-1 protein expression, P62 protein expression decreased, autophagosome fluorescence intensity increased, the apoptosis rate increased cleaved caspase 3 / caspase 3 ratio increased. Compared with TXNIP overexpression group, the autophagy in TXNIP overexpressing + 3-MA group was significantly inhibited after 3-MA intervention with autophagy inhibitor, and the apoptosis was significantly reduced. The above results suggest that overexpression of TXNIP in INS-1 cells under normal glycolipid concentration can promote apoptosis by inducing autophagy.