Effects of Fas, NF-?B and caspases on microvascular endothelial cell apoptosis induced by TNF?
- VernacularTitle:Fas、NF-?B及Caspases在TNF?介导的微血管内皮细胞凋亡中的作用
- Author:
Xiang CAO
;
Huiming JIN
- Publication Type:Journal Article
- Keywords:
Apoptosis;
Endothelium, vascular;
Tumor necrosis factor;
Caspases;
Antigens, CD95;
NF-kappa B
- From:
Chinese Journal of Pathophysiology
2000;0(08):-
- CountryChina
- Language:Chinese
-
Abstract:
AIM:To study the apoptotic effect of TNF? on rat pulmonary microvascular endothelial cells (PMVEC)and the role of Fas, NF-?B in its mechanism. METHODS: Apoptosis of PMVEC was analyzed and quantitated with TUNEL, flow cytometer. Northern blot was applied to assess the influence of TNF? on PMVEC Fas expression. Fas antibody was used to investigate the apoptotic effect of Fas on PMVEC. Activation of caspase-8 was examined by Western blot. Expression of caspase-3 was analyzed with histo-immunochemical staining. RESULTS:Growth curve showed that TNF? suppressed endothelial cell proliferation in a dose-dependent manner. After treatment with 5?10 6 U/L TNF?, apoptotic rate was 14.0%?3.1% detected with TUNEL, and 13.1% with flow cytometer. When the cells were co-cultured with TNF? and APDC, an NF-?B inhibitor, less cells were viable and more cells were positively stained with TUNEL. Fas expression in PMVEC was elevated after TNF? treatment. Co-culturing with Anti-Fas antibody aggravated PMVEC apoptosis. Caspase-8 activity and caspase-3 expression was elevated. Caspase-3 inhibitor significantly ameliorated PMVEC apoptosis. CONCLUSION: Large dose of TNF? (5?10 6 U/L) can induce apoptosis in rat PMVEC. NF-?B has an anti-apoptotic effect in PMVEC. TNF? up-regulates Fas expression in PMVEC, and the latter takes a part in apoptosis. Caspase-8 and caspase-3 are involved in PMVEC apoptosis induced by TNF?.