7-Ketocholesterol induces ROS-mediated mRNA expression of 12-lipoxygenase, cyclooxygenase-2 and pro-inflammatory cytokines in human mesangial cells: potential role in diabetic nephropathy

Publication date: Available online 15 November 2017 Source:Prostaglandins & Other Lipid Mediators Author(s): Yasuhiro Watanabe, Takashi Yamaguchi, Noriko Ishihara, Shoko Nakamura, Sho Tanaka, Rena Oka, Haruki Imamura, Yuta Sato, Noriko Ban, Hidetoshi Kawana, Masahiro Ohira, Naomi Shimizu, Atsuhito Saiki, Ichiro Tatsuno 7-Ketocholesterol (7-KCHO) is a highly proinflammatory oxysterol and plays an important role in the pathophysiology of diabetic nephropathy (DN). Lipoxygenases (LOXs) and cyclooxygenases (COXs) are also involved in the development of DN. The aim of this study was to clarify the effects of 7-KCHO on mRNA expression of LOXs and COXs as well as pro-inflammatory cytokines in human mesangial cells (HMC). We evaluated cell viability by WST-8 assay and measured mRNA expression by reverse transcription-polymerase chain reaction. Intracellular reactive oxygen species (ROS) production was evaluated by flow cytometry. Although 7-KCHO did not affect cell viability of HMC, 7-KCHO stimulated significant increases in mRNA expression of 12-LOX, COX-2 and pro-inflammatory cytokines. 7-KCHO also induced an increase in ROS production, while N-acetylcysteine partially suppressed the increase. The 12-LOX and COX-2 inhibitors also suppressed mRNA expression of cytokines. These findings may contribute to the elucidation of the molecular mechanism of the pathophysiology of DN.
Source: Prostaglandins and Other Lipid Mediators - Category: Lipidology Source Type: research