二十二碳六烯酸抑制慢性阻塞性肺疾病患者中性粒细胞核因子-κB p65的表达

DHA suppresses NF-κB p65 expression in neutrophils in patients with chronic obstructive pulmonary disease

摘要:

目的 探讨二十二碳六烯酸（DHA）在慢性阻塞性肺疾病（COPD）中的抗炎机制。方法 选取2011年12月至2012年12月在上海市徐汇区中心医院门诊就诊的患者40例，其中COPD稳定期患者20例为A组，COPD发作期患者20例为B组，分离外周静脉血中性粒细胞体外培养，用不同浓度的DHA（10，50和100μmol/L）处理0～72h（0，24，48和72h），收取培养液上清测定炎症因子白细胞介素（IL）-6，IL-8和肿瘤坏死因子α（TNF-α）水平，收取细胞蛋白做Western印迹法检测核因子κB（NF-κB）p65的表达。结果 DHA作用前B组炎症因子水平显著高于A组。DHA作用后，两组炎症因子水平都下降，并呈现浓度和时间依赖效应，B组下降趋势大于A组，高浓度DHA作用72h后，A组和B组炎症因子水平趋于一致。NF-κB p65的表达水平随DHA浓度和时间变化呈现下降趋势（P＜0.05）。结论 DHA可能通过抑制中性粒细胞的NF-κB p65蛋白的表达，显著性地降低了中性粒细胞分泌炎症因子IL-6、IL-8、TNF-α的水平，为DHA用于临床治疗COPD提供了理论依据。

Abstract:

Objective To investigate the anti-inflammatory effect and mechanism of docosahexaenoic acid (DHA) in patients with chronic obstructive pulmonary disease (COPD). Methods A total of 40 COPD outpatients in our department from December 2011 to December 2012 were recruited in this study. Twenty cases of them in stable period were assigned as group A, and the left 20 cases in exacerbation period were assigned into group B. Their peripheral blood neutrophils were isolated and cultivated. Then the cells were treated with DHA at different concentrations (10, 50 and 100μmol/L) for 0, 24, 48 and 72h, respectively. The levels of the inflammatory cytokines IL-6, IL-8, and TNF-α in culture supernatants were measured. The expression level of NF-κB p65 protein was detected with Western blotting. Results Before DHA treatment, the levels of inflammatory factors were significantly higher in group B than in group A. After DHA treatment, the levels dropped directly in a concentration- and time-dependent manner in both groups, but the downtrend was stronger in group B than in group A. After treated with high dosed DHA for 72h, the inflammatory cytokines levels in group A were not significantly different with those in group B. NF-κB p65 protein expression was decreased in a dose- and time-dependent manner (P＜0.05). Conclusions DHA significantly reduces the levels of inflammatory cytokines IL-6, IL-8, and TNF-α through inhibiting NF-κB p65 protein expression in neutrophils, providing the theoretical basis for DHA in clinical treatment of COPD.