Effect of methylglyoxal on osteoprotegerin expression in the pre-osteoblast MC3T3E1 cell line: involvement of oxidant pathways

摘要

Objective: This study aimed to evaluate osteoprotegerin (OPG) expression in MC3T3E1 preosteoblast cell line exposed to methylgyoxal (MG) with/without antioxidant blocking or iron chelating. Methods: MC3T3E1 preosteoblast cell line subclone 4 was obtained from American Type Culture Cell Collection (ATCC). Modulation of intracellular oxidative status was obtained by blockade of superoxide dismutase (SOD) using diethylthiocarbamoic acid (DETCA), blockade of gluthatione peroxidase (GPx) using mercaptosuccinate (MS), and iron chelating using deferoxamine (DFX). The MC3T3E1 preosteoblast cell line was exposed to MG at the concentration of 5 μM for 6 h of incubation time. Eight groups (n=3) were constituted, including the control group, the MG-exposed group, the DETCA/MS/DFX-exposed groups, and the MG+DETCA/MS/DFX-exposed groups. OPG was evaluated by ELISA assay kit. Results: The expression of OPG in MG-exposed group was not different than that in the control group. OPG expression was significantly reduced by DETCA and restored in the MG+DETCA-exposed group. MS exposure also significantly reduced OPG expression; addition of MG to MS again clearly reversed this effect. On the other hand, DFX administration did not affect OPG expression. Conclusion: Modulation of the intracelllular oxidative status via blockade of SOD or GPx clearly inhibits the OPG expression in preosteoblast cells. Addition of MG reversed this effect and reversed the fall of OPG expression.