TGF-β_1和TL1A在高糖所致血管内皮细胞凋亡中的作用

Effects of TGF-β_1 and TL1A on high glucose-induced apoptosis in endothelial cell

目的:观察高糖条件下,内皮细胞分泌的TGF-β1和TL1A对细胞凋亡的影响。方法:以22.4mmol/L葡萄糖培养细胞不同时间(0h,6h,12h,24h,48h),RT-PCR和Westernblot检测内皮细胞TGF-β1和TL1A表达,Annexin V-FITC/PI双染色、流式细胞仪测定细胞凋亡率。结果:高糖条件下HUVECTGF-β1和TL1A表达增加(均P<0.01),22.4mmol/L葡萄糖培养条件下,TGF-β1的表达高峰在12h,TL1A高表达峰值在48h。高糖条件下细胞凋亡率明显增加(21.06%±3.05%vs3.09%±0.32%,P<0.01)。在正常糖培养的HUVEC中加入外源性的TGF-β1和TL1A,均导致细胞凋亡率显著增高(15.26%±2.93%,55.70%±8.91%vs3.09%±0.32%,均P<0.01),在高糖培养液中加入抗TL1A抗体能明显抑制细胞凋亡发生(4.28%±0.48%vs21.06%±3.05,P<0.01),但加入抗TGF-β1抗体却不能逆转高糖诱导的细胞凋亡(20.93%±3.21vs21.06%±3.05%,P>0.05)。结论:高糖上调内皮细胞TGF-β1和TL1A的表达,TL1A介导高糖引起内皮细胞凋亡的作用,高糖引起内皮细胞凋亡与TGF-β1无关。

Objective To investigate the effects of TGF-β1 and TL1A on high glucose-mediated cells apoptosis in Human umbilical vein endothelial cell （HUVEC） .Method HUVECs were treated with media containing 22.4 mM of glucose for different time （0 h,6 h,12 h,24 h,48 h） experiments.TGF-β1 mRNA and TL1A mRNA expression were determined by RT-PCR,and the proteins of both were evaluated by Western blot.The apoptotic rate of HUVEC was determined by flow cytometry with annexin V-FITC/PI double staining.Results Exposure HUVEC to 22.4 mM glucose resulted in a significant increase in TGF-β1 and TL1A expression,compared with normal glucose （5.6 mM,P〈0.05 or P〈0.01） .The peak expression of TGF-β1 in HUVEC was at the first 12 h,while TL1A was at the first 48 h after treatment with high glucose.High glucose increased HUVEC apoptosis [（3.09 ± 0.32） % vs （21.06 ± 3.05） % ,P〈0.01].HUVEC apoptosis rate significantly increased after adding exogenous TGF-β1 or TL1A to media containing 5.6 mM of glucose for 24 h [（15.26 ± 2.93） % ,（55.70 ± 8.91） % vs （3.09 ± 0.32） % ,P〈0.01].TL1A antibody prevented high glucose-induced endothelial apoptosis,but TGF-β1 antibody did not.Conclusion High glucose up-regulates TGF-β1 and TL1A expression in HUVEC,TL1A mediates the apoptotic effects of high glucose,high glucose-induced endothelial apoptosis is independent of TGF-β1.