Troglitazone induces a rapid drop of mitochondrial membrane potential in liver HepG2 cells
- 作者：Bova ; Michael P. ; Tam ; Danny ; McMahon ; Gerald ; Mattson ; Matthew N.
- 关键词：CCCP ; carbonyl cyanide m-chloro phenylhydrazone ; HBSS ; Hanks balanced salt solution ; Δ ; Ψ ; ; mitochondrial membrane potential ; PPAR ; peroxisome proliferator-activated receptor ; ROS ; reactive oxygen species ; TMRE ; tetramethylrhodamine e
- 刊名：Toxicology Letters
- 出版年：2005
- 期刊代码：49_03784274
- 类别：pha
- 出版时间：January 15, 2005
- 卷：155
- 期：1
- 页码：41-50
- 文件大小：227 K
摘要
Troglitazone, a thiazolidinedione containing compound, was widely used to treat non-insulin dependent-diabetes. Unfortunately, troglitazone was associated with a sporadic liver toxicity that led to a cessation of its use clinically. Here we show that troglitazone induces a rapid and dose-dependent drop of mitochondrial membrane potential in liver HepG2 cells. The decrease in mitochondrial membrane potential induced by 100μM troglitazone was completed after 5min and similar in magnitude to that caused by carbonyl cyanide m-chloro phenylhydrazone. The troglitazone-induced loss of mitochondrial membrane potential preceded changes in cell permeability and cell count. In addition, troglitazone-induced a rise of intracellular calcium, subsequent to the drop in mitochondrial membrane potential, which was blocked by EGTA and the Na+/Ca2+ exchange inhibitor bepridil. Finally, application of 100μM troglitazone for 24h to HepG2 cells resulted in activation of caspase 3. The results of this study shed light on the molecular mechanisms by which troglitazone can cause cytotoxicity.