First Author | Xiao Y | Year | 2010 |
Journal | FEBS J | Volume | 277 |
Issue | 3 | Pages | 687-96 |
PubMed ID | 20050918 | Mgi Jnum | J:168272 |
Mgi Id | MGI:4887530 | Doi | 10.1111/j.1742-4658.2009.07514.x |
Citation | Xiao Y, et al. (2010) 3T3-L1 adipocyte apoptosis induced by thiazolidinediones is peroxisome proliferator-activated receptor-gamma-dependent and mediated by the caspase-3-dependent apoptotic pathway. FEBS J 277(3):687-96 |
abstractText | Although thiazolidinediones (TZDs) are potent promoters of adipogenesis in the preadipocyte, they induce apoptosis in several other cell types, such as cancer cells, endothelial cells and T-lymphocytes. In this study, we investigated the proapoptotic effect of TZDs in mature 3T3-L1 adipocytes, which express high levels of the peroxisome proliferator-activated receptor-gamma (PPARgamma) protein. Apoptosis was induced in mature 3T3-L1 adipocytes by treatment with troglitazone, pioglitazone or prostaglandin J2, and could be blocked by the PPARgamma antagonist GW9662. Treatment with PPARgamma agonists also decreased Akt-1 protein and phosphorylation levels without affecting phosphoinositide 3-kinase and PTEN. Further analysis indicated that in troglitazone-treated 3T3-L1 adipocytes, Bad phosphorylation and Bcl-2 protein levels were reduced, and Bax translocation to the mitochondria was increased. Subsequently, cytochrome c release and caspase-3 cleavage were observed. TZD-induced adipocyte apoptosis could be blocked by the caspase-3 inhibitor Ac-DEVD-CHO or by overexpression of Bcl2. In cultured rat primary adipocytes, similar apoptosis-inducing effects of troglitazone were also observed. Thus, TZDs promote apoptosis in adipocytes through a PPARgamma-dependent pathway. This apoptosis is mediated by the inhibition of Akt-1, which decreases Bad phosphorylation and activates the mitochondrial apoptotic pathway. |