Inhibitory effects of α-lipoic acid on cell proliferation and ICAM-1 expression induced by high glucose in rat mesangial cells

Objective:To investigate the effects of α-lipoic acid on cell proliferation and expression of intercellular adhesion molecule1(ICAM-1) induced by high glucose(HG) in rat mesangial cells(MCs).Methods: Rat mesangial cells were co-cultured with normal glucose(5.6 mmol/L,NG group),high glucose(25 mmol/L,HG group),and HG+α-lipoic acid(50,100,200,300 μmol/L)for 12,24 and 48 h,respectively.Cell proliferation was assessed by MTT;the levels of ICAM-1 in the supernatants were determined by enzyme-linked immunosorbent assay(ELISA);and ICAM-1 mRNA expression was measured by semi-quantitative RT-PCR.Results: α-lipoic acid at 50-300 μmol/L inhibited the proliferation of MCs.Semi-quantitative RT-PCR showed that α-lipoic acid(100 and 200 μmol/L)significantly inhibited the high glucose-induced increase of ICAM-1 mRNA((P)(0.01).) In addition,HG-induced up-regulation of ICAM-1 protein was remarkably reduced by 200 μmol/L α-lipoic acid([288.4±23.4] ng/ml) compared with HG group([542.3±35.6] ng/ml,P0.01).Conclusion: Certain concentrations of αlipoic acid can inhibit high glucose-induced proliferation of MCs and decrease the expression of ICAM-1 protein and mRNA.