Protective Effect of Lipoic Acid against Acrolein-Induced Cytotoxicity in IMR-90 Human Fibroblasts

Abstract

Acrolein is a highly reactive unsaturated hazardous air pollutant of human health concern, particularly as a component of cigarette smoke. In this study, the effects of acrolein on mitochondrial damage in IMR-90 (a human lung fibroblast cell line), and the reduction of this damage by R-alpha-lipoic acid were examined. Our results show that acute acrolein exposure exceeding 100 microM (24 h) in IMR-90 cells caused serious cytotoxicity, including decreases in cell viability, mitochondrial membrane potential, SOD activity, GSH and ATP levels, and acute exposure also increased in ROS levels. Pretreatment with R-alpha-lipoic acid effectively protected IMR-90 cells from acrolein toxicity. The results show that acrolein is a mitochondrial toxin in IMR-90 cells and that acrolein-induced oxidative mitochondrial dysfunction is reduced by R-alpha-lipoic acid. These experiments imply R-alpha-lipoic acid may be an effective antioxidant for reducing or preventing chronic oxidant-induced lung cells degeneration in vivo from a variety of sources, including cigarette smoke.