ATP敏感性钾通道在硫化氢抑制坏死性凋亡介导的高糖致H9c2心肌细胞炎症中的作用

Role of ATP-sensitive potassium channels in inhibitory effect of hydrogen sulfide on high glucose-induced inflammation mediated by necroptosis in H9c2 cardiac cells

目的:探讨ATP敏感性钾通道(K_ATP通道)在硫化氢(H2S)抑制坏死性凋亡介导的高糖(HG)致H9c2心肌细胞炎症中的作用。方法:应用Western blot法测定受体相互作用蛋白3(RIP3)和环氧化酶-2(COX-2)的表达水平;ELISA检测细胞培养液中白细胞介素-1β(IL-1β)和肿瘤坏死因子-α(TNF-α)的水平。结果:H9c2心肌细胞经HG(35 mmol/L葡萄糖)处理24 h,其RIP3的表达水平明显升高,100μmol/L K_ATP通道开放剂二氮嗪(DZ)和400μmol/L H_2S的供体硫氢化钠(Na HS)预处理心肌细胞30 min均可抑制HG对RIP3表达的上调;100μmol/L K_ATP通道阻断剂5-羟基癸酸(5-HD)预处理心肌细胞30 min可阻断Na HS对HG上调RIP3表达的抑制作用。另一方面,100μmol/L坏死性凋亡的特异性抑制剂necrostatin-1共处理或100μmol/L DZ、400μmol/L Na HS预处理心肌细胞均能抑制高糖引起的心肌细胞炎症,使COX-2表达及IL-1β和TNF-α的分泌水平均减少;而100μmol/L 5-HD能明显拮抗Na HS的上述抗炎症反应作用。结论:K_ATP通道在H_2S抑制坏死性凋亡介导的高糖致心肌细胞炎症反应中发挥重要的作用。

AIM： To investigate the role of ATP-sensitive potassium（K_ATP） channels in the inhibitory effect of hydrogen sulfide（ H_2S） on high glucose（ HG）-induced inflammation mediated by necroptosis in H9c2 cardiac cells.METHODS： The expression levels of receptor-interacting protein 3（ RIP3; an indicator of necroptosis） and cyclooxygenase-2（ COX-2） were determined by Western blot. The levels of interleukin-1β（ IL-1β） and tumor necrosis factor-α（TNF-α） were detected by ELISA. RESULTS： After H9c2 cardiac cells were treated with 35 mmol/L glucose（HG） for 24 h,the expression of RIP3 was significantly increased. Pre-treatment of the cells with 100 μmol / L diazoxide（ DZ; a K_ATPchannel opener） or 400 μmol / L Na HS（ a donor of H_2S） for 30 min considerably blocked the up-regulation of RIP3 induced by HG. Moreover,pre-treatment of the cells with 100 μmol / L 5-hydroxydecanoic acid（ 5-HD; a K_（ATP）channel blocker） attenuated the inhibitory effect of Na HS on HG-induced up-regulation of RIP3. On the other hand,co-treatment of the cells with 100 μmol / L necrostatin-1（ a specific inhibitor of necroptosis） or pre-treatment of the cells with 100 μmol / L DZ or 400 μmol / L Na HS attenuated HG-induced inflammatory responses,evidenced by decreases in the expression of COX-2 and secretion levels of IL-1β and TNF-α. However,pre-treatment of the cells with 100 μmol / L 5-HD significantly attenuated the above anti-inflammatory effects of Na HS. CONCLUSION： K_（ATP）channels play an important role in the inhibitory effect of H_2 S on HG-induced inflammation mediated by necroptosis in H9c2 cardiac cells.