泛肽-蛋白酶体对TRAIL诱导凋亡作用的影响

目的：探讨泛肽-蛋白酶体对TRAIL诱导细胞凋亡作用的影响。方法：对四种不同处理组（PBS；anti-DR5；lactacystin和anti-DR5加lactacystin）的RSAF细胞及SCID小鼠滑囊细胞分别用Hoechst 33342染色和TUNEL染色后，检测其细胞凋亡率。用Hoechst染色和Luminescent ATP Lite法定量分析Caspase抑制剂对细胞凋亡的影响。结果：Lactacystin阻断泛肽-蛋白酶体通路后，Anti-DR5与TRAILR2 结合后能诱导95%以上的RASF细胞出现凋亡。而分别用anti-DR5抗体和lactacystin单独处理的细胞却没有观察到这种现象。结论：泛肽-蛋白酶体通路参与了对TRAIL 诱导的细胞凋亡的调节。而Caspase 8 和Caspase 4的激活在泛肽-蛋白酶体参与TRAIL的凋亡信号传导调节中是必需的。

Effect of ubiquitin-proteasome pathway on TRAIL inducing apoptosis

Objective To determine the influence of ubiquitin-proteasome in regulating the TRAIL-mediated apoptosis.Methods RASF cells and SCID mice were divided into 4 groups treated with PBS,anti-DR5,lactacystin,and anti-DR5 plus lactacystin. The apoptosis of cells was detected with Hoechst 33342 and TUNEL. The effect of caspase inhibitor on cell apoptosis was analysed with Hoechst 33342 and Luminescent ATP Lite.Results Block ubiquitin-proteasome with lactacystin , a highly specific and irreversible proteasome inhibitor, induced 95% cell apoptosis both in vitro and in vivo. In contrast, there was no apoptosis of cells after the treatment with anti-DR5 antibody or lactacystin alone. Conclusion The inhibition of ubiquitin-proteasome pathway can sensitize rheumatoid arthritis synovial fibroblast cells to TRAIL- induced apoptosis, and the activation of caspase 8 and caspase 4 is necessary in this process.