[ROLE OF MITOCHONDRIAL REACTIVE OXYGEN SPECIES IN LIPOPOLYSACCHARIDE-PROMOTED ACCUMULATION OF INTRACELLULAR LIPID DROPLETS].

Abstract

It is known that in various cell types bacterial lipopolysaccharide (LPS) causes mitochondrial disfunction and promotes accumulation of triglycerides in intracellular lipid droplets. The precise mechanisms which mediate LPS-induced neutral lipid deposition remain poorly understood. In the present work performed on primary cultured epithelial cells isolated from the frog urinary bladder we studied the possible role of mitochondrial reactive oxygen species (mROS) in LPS-in-duced alteration of lipid metabolism. It was shown that LPS stimulated ROS production, decrea- 705 sed fatty acids oxidation, enhanced intracellular triglyceride deposition and promoted the formation of lipid droplets visualized by Nile red staining. Pretreatment of cells with mitochondrial-tar-geted antioxidant MitoQ at dose 25 nM for 2 h almost completely eliminated all the above effects of LPS. In contrast to MitoQ, a-tocopherol was ineffective. The data obtained indicate that increase of mROS level is a critical factor that mediates LPS-induced intracellular deposition of neutral lipids in epithelial cells.