二甲双胍对高糖培养 H9 c2细胞 Connexin43表达的影响

摘要

Aim To investigate the effect of metformin (Met) on connexin43(Cx43) expression in H9c2 cells cultured with high glucose and the relevant mecha-nisms.Methods Rat myocardial cells H9c2 were cul-tured with high glucose , then combined with 3μmol· L-1 and 5 μmol · L-1 of Met for 24 h respectively . The viability and toxicity of H9c2 cells were detected by MTT and LDH , respectively .The expression and distribution of Cx43 were detected by immunofluores-cence staining .The intracellular oxygen species reac-tive ( ROS) level was detected by fluorescencemicrosco-py.And the expression of Cx43, P-AMPK, AMPK and GAPDH was determined by Western blot .Results The viability of H9c2 cells was increased and the level of intracellular ROS was decreased in Met group , while there existed no significant difference in LDH release among groups.Met significantly increased the phos-phorylation of AMPK and the expression of Cx 43, and improved the distribution of Cx 43 also.Conclusion The beneficial effect of Met on cardiovascular system in diabetic patients may via up-regulating the expression of Cx43 and down-regulating of intracellular ROS through activation of AMPK .%目的研究二甲双胍（metformin， Met）对高糖培养下的H9c2细胞缝隙连接蛋白43（connexin43，Cx43）表达的影响及其机制。方法高糖培养的大鼠H9 c2心肌细胞分别加入3和5μmol· L－1的两种不同浓度的二甲双胍继续培养24 h。 MTT实验检测H9c2细胞活力；LDH释放实验检测细胞毒力；细胞免疫荧光实验检测Cx43的表达和分布；荧光法检测细胞内活性氧（ ROS ）水平；Western blot 检测 Cx43、p-AMPK、AMPK和GAPDH的表达。结果 Met能增加H9c2细胞活力，降低细胞内ROS水平，对LDH释放差异无显著性；Met使AMPK磷酸化水平明显升高，增加心肌Cx43表达，改善Cx43的分布。结论 Met可能通过激活AMPK途径，增加心肌细胞Cx43的表达和减少细胞内ROS的产生，进而发挥心血管的保护效应。