辛伐他汀抑制oxLDL诱导的巨噬细胞焦亡

Simvastatin inhibits the oxidized LDL-induced macrophages pyroptosis

目的探讨辛伐他汀在氧化低密度脂蛋白(ox LDL)诱导巨噬细胞焦亡中的作用及机制。方法 ox LDL作用于J774A.1小鼠巨噬细胞,采用乳酸脱氢酶(LDH)释放试剂盒检测LDH的释放,荧光显微镜观察吖啶橙(AO)、溴化乙锭(EB)的染色情况来判断焦亡细胞膜的完整性;Western blot检测LC3-Ⅱ/Ⅰ、caspase-1与白介素-1β(IL-1β)的蛋白表达情况;分别加入辛伐他汀、3-甲基腺嘌呤(3-MA)自噬阻断剂等药物后,检测上述实验结果的变化情况。结果在ox LDL诱导的巨噬细胞脂质聚集的过程中,辛伐他汀药物有保护膜完整性的作用,并且显著减少LDH的释放,AO/EB荧光染色结果可观察到橘红色荧光(EB)所占比例显著降低,并抑制caspase-1的激活和IL-1β的分泌。然而,当巨噬细胞的自噬过程被3-MA所阻断时,Western blot结果显示LC3-Ⅱ/Ⅰ的表达下调,caspase-1的活性和成熟的IL-1β分泌增加;同时LDH实验和染色实验结果也显示,LDH释放增多、AO/EB染色中橘红色荧光增加,表明ox LDL诱导的巨噬细胞膜的损伤进一步加重。结论辛伐他汀可抑制ox LDL诱导的巨噬细胞焦亡,可能与增强ox LDL诱导的巨噬细胞自噬有关。

Objective To investigate the effect of simvastatin on oxLDL induced macrophages pyroptosis. Methods OxLDL treated J774A. 1 mouse macrophages. Acridine orange/ethidium bromide （AO/EB） staining method and LDH release assay was used to observe the membrane integrity; Western blot was used to detect the expression of LC3-Ⅱ/Ⅰ , caspase-1 and interleukinIL-1β, compared with the group after treatment with simvastatin and 3- methyladenine （3-MA）. Results Simvastatin could protect the plasma membrane integrity and inhibit the activa- tion of caspase-1 and the maturation of IL-1 during the process of lipid accumulation in macrophages induced by oxLDL. LDH release decreased and AO/EB staining showed orange fluorescence reduce. However, when the auto- phagy of macrophage was blocked by 3-MA, Western blot showed that the expression of LC3-Ⅱ/Ⅰ was down-regu-lated, the activity of caspase-1 and the secretion of mature IL-1βincreased. Furthermore, the results of LDH re- lease increased and AO/EB staining orange fluorescence increase indicated that the damage of macrophage cell membrane induced by oxLDL is significantly worse after 3-MA treatments. Conclusion Simvastatin inhibit the ox- LDL-induced macrophages pyroptosis,which may be associated with enhanced oxLDL-induced macrophage autoph- agy