抵抗素对内皮细胞NO生成的影响及Akt信号机制

目的探讨抵抗素对内皮细胞NO生成的影响及其可能的信号机制。方法分离、培养人脐静脉内皮细胞（HUVECs），以不同浓度抵抗素（15、50、100ng／ml）干预。荧光显微镜检测各组细胞中N0的生成，RT-PCR检测eNOS mRNA表达水平，Western blot检测Akt和eNOS磷酸化水平。结果15、50、100ng／ml抵抗素干预HUVECs 24h后，胰岛素刺激的内皮NO生成显著降低（三组分别为4．01±0．69、3．764±0．71、3．73±0．45，vs对照组P均〈0．05），同时伴有内皮Akt和eNOS磷酸化水平的降低（us对照组P均〈0．05），而eNOS mRNA表达无显著改变。结论抵抗素可通过P13K／Akt途径影响HuVECs eNOS磷酸化水平，进而调节内皮细胞NO生成，但该影响并非Akt依赖性。

Effect of resistin on nitric oxide production of human endothelial cells and on the Akt signaling mechanism

Objective To investigate the effect of resistin on HUVECs NO production and on the Akt signaling. Methods HUVECs were isolated and cultured for experiment. Endothelial cells were incubated with recombinant human resistin （15, 50, 100ng/ml） for 24 hours and stimulated by insulin for 20 min. NO production of HUVECs was detected by fluorescence microscope. The eNOS mRNA expression level and eNOS and Akt phoshporylation levels were measured by RT-PCR and Western-blot. Results Interventions by resistin for 24h resulted in the decrease of insulin-stimulated NO production （Convs resistin of 15, 50, 100ng/ml group：4.89±0.58 versus 4.01±0.69, 3.76±0. 71, 3. 734±0.45 respectively, P 〈 0. 05）. At the same time, Akt and eNOS phosphorylation levels were decreased obviously, hut there was no significant change in eNOS mRNA expression level. Conclusions Resistin may inhibit the NO production of HUVECs through the regulation of eNOS phosphorylation and may be independent on PI3K/Akt signaling of insulin.