目的:探讨硫化氢(H2S)是否通过调控核因子κB(NF-κB)通路抑制阿霉素(DOX)引起的心肌细胞炎症反应与细胞毒性。方法:应用Western blotting法测定NF-κB p65表达;酶联免疫吸附试验(ELISA)测定白细胞介素(IL)-1β、IL-6及肿瘤坏死因子α(TNF-α)的分泌水平;细胞计数盒(CCK-8)检测细胞存活率,Hoechst 33258核染色法检测凋亡细胞的形态学及数量的变化。结果:应用5 μmol/L DOX处理H9c2心肌细胞明显上调磷酸化NF-κB p65(p-p65)表达水平,并引起炎症反应和细胞毒性,表现为IL-1β、IL-6、TNF-α的分泌水平升高、凋亡细胞数量增多及细胞存活率降低。400 μmol/L NaHS(H2S供体)预处理30 min能显著抑制DOX对心肌细胞p-p65表达的上调作用,并减轻DOX引起的炎症反应和细胞损伤,使IL-1β、IL-6、TNF-α的分泌水平下降、凋亡细胞数量降低及细胞存活率升高。与NaHS的作用相似,NF-κB抑制剂吡咯烷二硫代氨基甲酸盐(PDTC,100 μmol/L)预处理也能阻断DOX引起的心肌炎症反应和细胞毒性。IL-1受体拮抗剂(IL-1Ra, 20 μg/L)与DOX共处理能拮抗DOX对心肌细胞NF-κB p65的激活作用及细胞毒性作用。结论:在DOX引起的心肌细胞炎症中,NF-κB通路与IL-1β之间存在正的相互作用;H2S可通过抑制NF-κB通路保护心肌细胞对抗DOX引起的炎症反应与细胞毒性。
AIM:To investigate whether hydrogen sulfide (H2S) attenuates doxorubicin (DOX)-induced inflammation and cytotoxicity in rat cardiomyocytes (H9c2 cells) by modulating nuclear factor κB (NF-κB) pathway. METHODS:The expression of NF-κB p65 was measured by western blotting. The secretion levels of interleukin (IL)-1β, IL-6 and tumor necrosis factor α (TNF-α) were tested by enzyme-linked immunosorbent assay (ELISA). Cell viability was detected by Cell Counting Kit-8 (CCK-8) assay. Hoechst 33258 nuclear staining was used to detect the morphological changes and number of apoptotic cells. RESULTS:Treatment of H9c2 cells with 5 μmol/L DOX significantly up-regulated the expression level of phosphorylated NF-κB p65 (p-p65), and induced inflammation and cytotoxicity, as evidenced by increases in secretion levels of IL-1β, IL-6 and TNF-α and number of apoptotic cells as well as a decrease in cell viability. Pretreatment of H9c2 cells with 400 μmol/L NaHS (a donor of H2S) for 30 min markedly depressed the up-regulation of p-p65 expression induced by DOX. In addition, NaHS pretreatment also reduced DOX-induced inflammatory response and injury, leading to decreases in IL-1β, IL-6 and TNF-α secretion and number of apoptotic cells as well as an increase in cell viability. Similar to the effect of NaHS, pretreatment with 100 μmol/L pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF-κB, also blocked DOX-induced cardiac inflammation and cytotoxicity. Co-administration of IL-1 receptor antagonist (IL-1Ra) and DOX reduced DOX-induced activation of NF-κB and cytotoxicity in H9c2 cells. CONCLUSION:During the DOX-induced cardiomyocyte inflammation, there is positive interaction between NF-κB pathway and IL-1β. H2S may protect cardiomyocytes against DOX-induced inflammatory response and cytotoxicity by inhibiting NF-κB pathway.