感染大鼠骨骼肌细胞内核因子-κB在胰岛素信号转导障碍中的作用  

Nuclear factor kappa B impairs insulin signaling pathway in skeletal muscle cells of rat with sepsis

作　　者：燕晓雯[1] 李维勤[1] 李秋荣[1] 李宁[1] 黎介寿[1] 

机构地区：[1]南京军区南京总医院全军普通外科研究所,210002

出　　处：《中华外科杂志》2009年第16期1257-1260,共4页Chinese Journal of Surgery

基　　金：军队“十一五”科研基金重点攻关项目（06G041）

摘　　要：目的研究感染大鼠骨骼肌细胞内核因子-κB（NF—κB）在胰岛素信号转导障碍中的作用。方法SD大鼠随机分为对照组和感染组。感染组大鼠使用盲肠结扎穿孔（CLP）的方法制造大鼠感染模型。2组实验大鼠分别在手术后8、16、24、48和72h取腓肠肌。光镜下观察HE染色骨骼肌细胞形态。使用免疫印迹和免疫沉淀法半定量分析骨骼肌中胰岛素受体底物-1（IRS-1）及其酪氨酸（Tyr）磷酸化和丝氨酸（Ser^307）磷酸化含量变化，凝胶电泳迁移率改变分析法测定骨骼肌细胞NF—κB活性。结果HE染色光镜下与对照组相比感染组大鼠CLP术后8h时骨骼肌细胞组织内无明显炎性细胞浸润。骨骼肌细胞IRS．1 Tyr磷酸化水平在感染组大鼠术后明显低于对照组（P〈0．01）；IRS—1 Ser^307磷酸化水平在术后明显高于对照组（P〈0．01）。术后骨骼肌细胞内NF—κB活性在术后明显高于对照组（P〈0．01）。Spearman相关分析显示骨骼肌细胞内NF—κB活性与IRS-1Tyr磷酸化水平呈显著负相关（r=0．972，P〈0．01），而与IRS-1Ser^307磷酸化水平呈显著正相关（r=0．969，P〈0．01）。结论感染状态下机体胰岛素抵抗产生的主要机制是IRS-1酪氨酸磷酸化水平降低而丝氨酸（Ser^307）水平升高，这时骨骼肌细胞内虽无明显炎性细胞浸润，但NF—κB的活性明显增强，并与胰岛素信号转导障碍密切相关，可能在感染引起机体胰岛素抵抗中起重要作用。Objective To investigate the effects of nuclear factor kappa B （ NF-κB ） on insulin signaling in skeletal muscle cells of rat with sepsis. Methods SD rats were randomly divided into two groups ： control group and sepsis group. Sepsis model was reproduced by cecal ligation and puncture in sepsis group. At 8, 16, 24, 48 and 72 h after operation, the gastroenemius was harvested. Conventional HE staining was used to observe the morphology of skeletal muscle cells. IRS-1 protein and tyrosine phosphorylation of IRS-1 and Ser307 phosphorylation of IRS-1 were detected by Western Blotting and immunoprecipitation. Activities of NF-κB in skeletal muscle cells were detected by eleetrophoretic mobility shift assay. Results Tyrosine phosphorylation of IRS-1 in sepsis group was significantly lower than in control group （P 〈0. 01 ）, while Set^307 phosphorylation of IRS-1 in sepsis group was significantly higher than in control group （P 〈 0. 01 ）. In sepsis group, NF-κB activity in skeletal muscle cells was significantly higher than in control group （P 〈 0. 01 ）. There was significant negative correlation between activity of NF-κB and tyrosine phosphorylation of IRS-1 （ r = 0. 972, P 〈 0. 01 ）. There was significant positive correlation between activities of NF-κB and Set307 phosphorylation of IRS-1 （ r = 0. 969, P 〈 0. 01 ）. Conclusions There is no inflammatory cell infiltrate in skeletal muscle cells with sepsis. But the activity of NF-κB in skeletal muscle cells is obviously enhanced, and it is closely related with disorder of insulin signaling in skeletal muscle cells of rat with sepsis.

关 键 词：感染 胰岛素抗药性 核因子-ΚB 大鼠 

分 类 号：R686[医药卫生—骨科学]