长链n-3多不饱和脂肪酸对肠上皮细胞促炎细胞因子基因mRNA表达的影响

本试验旨在探讨长链n-3多不饱和脂肪酸(LC n-3 PUFA)对肠上皮细胞促炎细胞因子基因mRNA表达的影响.试验选用大鼠肠上皮细胞系IEC-6细胞为模型,分为4个处理,分别为对照、脂多糖(LPS,1μg/mL)、LPS(1μg/mL)+二十二碳六烯酸(DHA,100 μmol/L)和LPS(l μg/mL)+二十碳五烯酸(EPA,100μmol/L),每个处理3个重复,每孔为1个重复.细胞先用DHA、EPA或等量二甲基亚砜(DHA和EPA的溶剂,对照)预处理48h,再用LPS处理3h,收集细胞提取总RNA,采用实时定量PCR方法分析肿瘤坏死因子-α(TNF-α)、白介素-1β(IL-1β)和白介素-6(IL-6)的基因mRNA表达水平的差异.结果表明:LPS极显著上调了细胞中TNF-α、IL-1 β和IL-6的基因mRNA表达水平(P＜0.01),EPA均极显著或显著削弱了细胞内LPS诱导的TNF-α(P＜0.01)、IL-1β(P ＜0.01)和IL-6的基因mRNA水平(P＜0.05)的上调,而DHA仅显著削弱了细胞内LPS诱导的IL-1β的基因mRNA水平的上调(P＜0.05).结果提示,LC n-3 PUFA在肠上皮细胞中具有抗炎作用,且在本试验条件下EPA的抗炎效果要优于DHA.

Long-Chain n-3 Polyunsaturated Fatty Acids Affect mRNA Expression of Pro-Inflammatory Cytokine Genes in Intestinal Epithelial Cells

This present study was conducted to investigate the effects of long-chain n-3 polyunsaturated fatty acids(LC n-3 PUFA) on the mRNA expression of pro-inflammatory cytokine genes in intestinal epithelial cells.IEC-6 cells from rat intestinal epithelial cells were used as the experimental model and subjected to four treatments with three replicates in each treatment and one well per replicate.The treatments were as follows: control,lipopolysaccharide(LPS,1 μg/mL),LPS(1 μg/mL)+docosahexaenoic acid(DHA,100 μmol/L) and LPS(1 μg/mL)+eicosapentaenoic acid(EPA,100 μmol/L).IEC-6 cells was collected for total RNA extraction after 48 h pretreatment with DHA,EPA or equivalent amounts of dimethyl sulfoxide(solvent of DHA and EPA,control) and 3 h treatment with LPS.The mRNA expression levels of tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β) and interleukin-6(IL-6) genes were determined using real-time quantitative PCR.The results showed that the mRNA expression levels of TNF-α,IL-1β and IL-6 genes were significantly up-regulated after LPS challenge(P<0.01),EPA significantly attenuated LPS-induced upregulation of mRNA expression levels of TNF-α(P<0.01),IL-1β(P<0.01) and IL-6 genes(P<0.05),while DHA only significantly attenuated LPS-induced upregulation of mRNA expression level of IL-1β gene(P<0.05).These results indicate that LC n-3 PUFA has an anti-inflammatory effect in intestinal epithelial cells,and the effect of EPA is more efficient than that of DHA under conditions in this experiment.