瘦素对巨噬细胞IL-1α的表达和氧化应激的调节作用

Leptin-induced IL-1α expression by increasing peroxide and superoxide in macrophages

目的:研究瘦素(leptin)对小鼠腹腔巨噬细胞(PM)产生白介素1α(IL-1α)的影响及氧化应激在这一过程中的作用。方法:体外培养的小鼠PM,按瘦素不同浓度和/或不同的培养时间以及自由基清除剂catalase或SOD进行分组,分别收集培养细胞和上清液,用ELISA方法测定培养上清中IL-1α水平,用激光共聚焦显微镜检测细胞内过氧化氢以及超氧阴离子的产生,用逆转录-聚合酶链式反应(RT-PCR)测定IL-1α mRNA的表达。结果:瘦素能够剂量依赖地诱导小鼠PM产生IL-1α,瘦素浓度为75μg/L时IL-1α表达至峰值,是对照组的12.2倍,并在瘦素作用2 h达高峰。瘦素可增加细胞内H2O2和O2.-的量,分别是对照组的2.1倍和17.4倍。H2O2的特异性清除剂catalase能够抑制瘦素引起的H2O2产生和IL-1α mRNA表达,分别比瘦素处理组减少79%和65%。O2.-的特异清除剂SOD可使瘦素引起的O2.-产生和IL-1αmRNA表达比瘦素处理组减少93.8%和70%。结论:瘦素在小鼠PM通过增加H2O2和O2.-的产生而诱导细胞表达IL-1α。

AIM： To study the effects of leptin on interleukin 1 α （ IL - 1 et） secretion in murine peritoneal macrophages （ PM ） and whether peroxide and superoxide are involved in this process. METHODS ： The murine PMs cultured in vitro were divided into groups according to the concentrations of leptin and the cultured time. The level of IL - 1 α in the culture supernatant was measured by ELISA. Confocal laser scanning microscope was used to determine the generation of peroxide and superoxide. Reverse transcription - polymerase chain reaction （ RT - PCR ） was used to measure the expression of IL - 1 α mRNA in PM. RESULTS ： Leptin induced IL - 1 α expression in murine PMs and the secretion of IL -1α reached the maximum when stimulated with 75 μg,/L of leptin, which was 12. 2 -fold compaired with the control. Leptin also stimulated H2O2 and O2^- generation in murine PM, which was 2.1 -folds and 17.4 -fold compaired with the control group, respectively. Catalase, the specific eliminator for H2O2 , significantly suppressed the production of H2O2 and IL - 1α mRNA expression induced by leptin in murine PM by 79% and 65% compared to the leptin group. Specific eliminator for O7 , SOD, inhibited the O2^-generation and IL - 1α mRNA expression stimulated by leptin by 93. 8% and 70% compared to leptin group. CONCLUSION： Leptin induces IL - 1 α production partly by inducing H2O2 and O2^- generation in murine PM.