β-胡萝卜素对脂多糖刺激巨噬细胞RAW264.7炎症因子的影响及其机制

摘要

Objective:To investigate the effects and mechanism of β-carotene on inflammatory factors (IL-1 β,IL-6,TNF-α) in LPS-induced RAW264.7 cells.Methods:Firstly,RAW264.7 cells of being induced by 4 (5 μg/ml)for 24 h were treated with different concentration of β-carotene (20,40,80,160 pmol/L)for 3 h.The cells viability was measured by MTIT,the mRNA relative expression of IL-1 β,IL-6,TNF-cα was detected by fluorescence quantitative PCR,the secretion capacity of IL-1 β,IL-6,TNF-α was detected by ELISA and the protein relative expression of NF-κB p65 protein was measured by Western blot.Secondly,RAW264.7 cells were induced by LPS(5 μg/ml) and different concentration of PDTC(1,5,10 μg/ml)for 24 h,NF-κB p65 protein was measured by Western blot and inflammatory factors were detected by fluorescence quantitative PCR and ELISA.Finally,compared the changes in the relative expression of inflammatory factors and NF-κB p65 protein between LPS+PDTC group and LPS+PDTC + β-carotene group.Results:Compared with the LPS-induced group,β-carotene could increase the cell viability of LPS-induced RAW264.7 cells and inhibied the relative expression of inflammatory factors and NF-κB p65 protein.Inhibited the relative expression of NF-κB p65 protein could reduce the relative expression of inflammatory factors.Compared with the LPS+PDTC group,LPS +PDTC + β-carotene group could inhibit the relative expression of inflammatory factors significantly (P＜0.05).But,there was little difference about the relative expression of NF-κB p65 protein between this two groups.Conclusion:β-carotene inhibits the relative expression of inflammatory factors(IL-1 β,IL-6,TNF-α) in LPS-induced RAW264.7 cells through inhibition of NF-κB p65 protein in NF-κB pathway,this pathway isn't unique.%目的:探讨β-胡萝卜素对脂多糖(LPS)刺激巨噬细胞RAW264.7炎症因子的影响及其机制.方法:采用5μ.g/ml的LPS刺激巨噬细胞24h后用不同浓度的β-胡萝卜素(20、40、80、160μmol/L)处理细胞3h,MTT法测细胞活性,荧光定量PCR测炎症因子IL-1β、IL-6、TNF-α mRNA相对表达量,ELISA测炎症因子IL-1β、IL-6、TNF-α.的分泌量,Western blot 测NF-κB p65蛋白相对表达量.5μg/ml的LPS和不同浓度的NF-κB抑制剂PDTC(1、5、10μg/ml)共同处理巨噬细胞24 h,Western blot测NF-κB p65蛋白相对表达量,荧光定量PCR、ELISA测炎症因子的表达和分泌.比较LPS+PDTC组和LPS+PDTC+β-胡萝卜素组炎症因子和NF-κB p65蛋白相对表达的变化.结果:与LPS组相比,不同浓度的β-胡萝卜素对LPS刺激的巨噬细胞的细胞活性有提升作用,对炎症因子和NF-κB p65蛋白的表达有抑制作用;抑制NF-κB蛋白的表达可以抑制LPS刺激的巨噬细胞炎症因子的分泌;LPS+PDTC+β-胡萝卜素组对炎症因子的抑制作用比LPS+PDTC组明显,且差异显著(P＜0.05),但两组对NF-κB p65蛋白的表达不明显.结论:β-胡萝卜素可以通过抑制NF-κB通路中NF-κB p65蛋白的表达抑制LPS刺激的巨噬细胞炎症因子IL-1β、IL-6、TNF-α的分泌,且此通路不是唯一相关的通路.