N-乙酰半胱氨酸对脂多糖诱导的血管内皮细胞炎症损伤的影响

目的:探讨N-乙酰半胱氨酸(NAC)是否对脂多糖(LPS)刺激的血管内皮细胞具有保护作用,为NAC用于治疗种植体周围炎、牙周炎等提供理论基础。方法:通过细胞计数试剂盒(CCK-8)法检测不同浓度的LPS或NAC对人脐静脉血管内皮细胞(HUVECs)增殖的影响,以获得刺激HUVECs的最适药物浓度。添加最佳药物浓度的LPS和(或)NAC处理HUVECs 24 h,实时半定量聚合酶链反应(RT-qPCR)检测炎症因子白细胞介素-8(IL-8)、肿瘤坏死因子-α(TNF-α)和细胞粘附分子-1(ICAM-1)的mRNA表达;酶联免疫吸附试验(ELISA)检测TNF-α和IL-8的蛋白表达;Western blot法检测ICAM-1和NF-κB信号通路的表达情况。结果:LPS刺激HUVECs过量表达炎症因子TNF-α、IL-8和ICAM-1。此外,LPS增加NF-κB通路的磷酸化P65(pP65)表达。然而,NAC预处理HUVECs后,显著抑制了LPS引起的TNF-α、IL-8和ICAM-1表达的增加及降低了pP65的分泌水平。结论:本结果表明NAC保护血管内皮细胞免受LPS介导的炎症损伤,从而减轻炎症反应,其潜在的机制可能与NF-κB信号通路有关。

Effect of N-acetylcysteine on Inflammatory Injury Induced by Lipopolysaccharide in Vascular Endothelial Cells

Objective:To investigate whether N-acetylcysteine(NAC)has protective effects on lipopolysaccharide(LPS)-stimulated vascular endothelial cells,and provide a theoretical basis for the treatment of peri-implantitis and periodontitis.Methods:The effects of different concentrations of LPS or NAC on proliferation of human umbilical vein endothelial cells(HUVECs)were measured by cell counting kit 8(CCK-8)to obtain the optimal drug concentration for stimulation of HUVECs.After adding the optimal drug concentration of LPS and/or NAC to treat HUVECs for 24 h,real-time semi-quantitative polymerase chain reaction(RT-qPCR)was used to detect the mRNA expression of inflammatory factors interleukin-8(IL-8),tumor necrosis factor-α(TNF-α),and cell adhesion molecule 1(ICAM-1).Protein expression of TNF-αand IL-8 were detected by enzyme-linked immunosorbent assay(ELISA).The protein expressions of ICAM-1 and NF-κB signaling pathway were detected by western blot.Results:LPS stimulated HUVECs to overexpress inflammatory factors TNF-α,IL-8,and ICAM-1.In addition,LPS increased phosphorylation of P65(pP65)expression in the NF-κB pathway.However,NAC pretreatment of HUVECs significantly inhibited the increase of TNF-α,IL-8,and ICAM-1 expression induced by LPS and decreased the secretion level of pP65.Conclusion:NAC protects HUVECs against LPS-mediated inflammatory reaction and alleviates inflammation.The underlying mechanism is related to the NF-κB pathway.