低糖培养对H9c2心肌细胞的自噬功能和细胞凋亡的影响

Effect of Low Glucose Incubation on the Activity of Autophagy and Apoptosis in H9c2 Cells

目的研究低糖培养对H9c2心肌细胞自噬活性的影响及此时自噬功能对细胞凋亡水平的影响。方法用33.3mmol/L葡萄糖浓度的培养基培养H9c2细胞后用2.5mmol/L葡萄糖浓度培养基处理细胞4h作为低糖组(LG组),高糖组(HG组)维持33.3mmol/L的葡萄糖浓度,对照组(Con组)维持5.5mmol/L的葡萄糖浓度;LG组加入自噬抑制剂3-MA作为抑制剂组(LG+3-MA组)。采用LDH检测试剂盒检测细胞毒性;MTT法检测H9c2细胞增殖能力;Western blot法检测caspase3、LC3、Beclin-1的表达量。结果与Con组和HG组相比,LG组LDH活性显著增加,细胞增殖能力显著降低,caspase3、LC3-Ⅱ和Beclin-1表达显著增加;而与LG组比较,抑制剂组LC3-Ⅱ、Beclin-1表达降低,同时caspase3以及细胞毒性降低,细胞活力增加。结论低糖培养通过激活H9c2心肌细胞的自噬活性引起细胞凋亡。

Objective To investigate the effects of low glucose incubation on autophagy activity and autophagy on apoptosis in H9c2 cells. Methods DMEM of 2.5mmol/L glucose concentration was used to replace that of 33.3mmol/L glucose concentration maintaining for 4h as the low glucose group （LG）. The high glucose group （HG） was maintained 33.3mmol/L glucose concentration environment,and the control group （Con group） was maintained 5.5mmol/L glucose concentration environment all the time. In addition, autophagy inhibitor 3-MA was added to LG as the inhibitor group （LG＋3-MA）. Lactate dehydrogenase assay was used to detect cytotoxicity; MTT assay was used to detect the proliferation of H9c2 cells; Western blotting assay was used to detect the expression of caspase3, LC3 and Beclin-1. Results Compared with the Con group and RG group, the activity of LDH in LG group was increased and the cell proliferation capacity of LG group was reduced. The protein levels of caspase3, Beclin-1 and ratio of LC3-Ⅱ/LC3-Ⅰ were also increased in LG group which was all reversed in LG＋3-MA group. Conclusion Low glucose increase cell apoptosis through activating autophagy in H9c2 cells.