苦豆碱对缺血再灌注引起的H9c2心肌细胞损伤和炎症应答的作用

目的:明确苦豆碱对缺血再灌注(I/R)引起的大鼠心肌H9c2细胞损伤和炎症应答的作用及其机制。方法:采用缺氧/复氧的方法体外模拟缺血再灌注(SI/R)心肌损伤,用不同浓度苦豆碱处理,MTT实验分析苦豆碱对H9c2细胞存活率的影响;流式细胞术检测细胞凋亡;试剂盒检测乳酸脱氢酶(LDH)和丙二醛(MDA)的水平及caspase-3的活性;ELISA分析多种炎性因子水平;同时用Western blot法分析苦豆碱对PI3K/AKT信号通路的影响。结果:苦豆碱可对抗SI/R抑制的H9c2细胞存活率,同时明显降低SI/R引起的LDH及MDA浓度的增加(P0.05)。此外,苦豆碱能够显著抑制SI/R触发的细胞凋亡(P0.05),同时降低SI/R处理后引起的caspase-3活性的增加,并上调Bcl-2/Bax比值(P0.05)。与SI/R组相比,苦豆碱处理可显著性降低H9c2心肌细胞炎性因子白细胞介素6、肿瘤坏死因子α和白细胞介素1β的浓度(P0.05)。此外,与SI/R组相比,苦豆碱处理后可显著增加p-PI3K和p-AKT的蛋白水平(P0.05);当用LY294002抑制PI3K/AKT通路后,苦豆碱促心肌细胞存活、抗凋亡及抗炎症的作用明显减弱(P0.05)。结论:苦豆碱可通过激活PI3K/AKT信号通路对抗心肌细胞缺血再灌注引起的损伤及炎症应答,提示其对心肌缺血再灌注损伤的防治具有潜在应用价值。

Role of aloperine on ischemia-reperfusion-induced injury and inflammatory response in H9c2 cardiomyocytes

AIM: To explore the role of aloperine in ischemia-reperfusion (I/R)-induced H9c2 cardiomyocyte injury and inflammation.METHODS: The H9c2 cardiomyocytes were cultured under hypoxia and re-oxygenation conditions to simulate ischemia-reperfusion (SI/R) injury. After treatment with aloperine at various doses, the cell viability was measured by MTT assay. The cell apoptosis was analyzed by flow cytometry. Simultaneously, the levels of lactate dehydrogenase (LDH), malonaldehyde (MDA) and caspase-3 activity were detected by the commercial kits. The levels of inflammatory cytokines were also detected by ELISA. Moreover, the effects of aloperine on the activation of PI3K/AKT signaling pathway were determined by Western blot.RESULTS: Pre-treatment with aloperine remarkably abated the inhibitory effect of SI/R on H9c2 cell viability, and decreased the elevations of LDH and MDA triggered by SI/R (P<0.05). Pre-treatment with aloperine dramatically suppressed the cell apoptosis induced by SI/R treatment (P<0.05), concomitant with the decrease in caspase-3 activity and increase in Bcl-2/Bax ratio (P<0.05). In contrast to SI/R group, aloperine treatment notably restrained the concentrations of pro-inflammatory cytokines, including interleukin-6, tumor necrosis factor-α and interleukin-1β (P<0.05). Furthermore, aloperine remarkably increased the protein levels of p-PI3K and p-AKT. While blocking the PI3K/AKT pathway with its specific inhibitor LY294002, the viability-promoting, anti-apoptotic and anti-inflammatory effects of aloperine on the H9c2 cells were obviously attenuated (P<0.05).CONCLUSION: Alope-rine protects against cardiomyocytes from I/R injury and inhibits inflammatory responses by activating the PI3K/AKT signaling pathway, implying a potential benefic role of aloperine against myocardial I/R injury.