Roles of oxidative stress,apoptosis,and heme oxygenase-1 in ethylbenzene-induced renal toxicity in NRK-52E cells

Abstract

Ethylbenzene is an important industrial chemical, but its potential toxicity is a recent concern. Our previous study investigated the renal toxicity of ethylbenzene in vivo. Rat renal epithelial cells (NRK-52E cells) were incubated with 0, 30, 60, and 90 µmol/L of ethylbenzene for 24 h in vitro to investigate ethylbenzene-induced oxidative stress, apoptosis, and the expression of heme oxygenase 1 (HO-1) and nuclear factor (erythroid 2)-related factor 2 (Nrf2). The cell survival rate in the ethylbenzene-treated groups was significantly lower than the control group. Ethylbenzene significantly increased intracellular reactive oxygen species and apoptosis. Malondialdehyde levels were significantly elevated compared with the control group, while glutathione levels and glutathione peroxidase activities were decreased in ethylbenzene-treated groups. The activities of catalase and superoxide dismutase were also markedly reduced. A significant dose-dependent increase in HO-1 and Nrf2 messenger RNA expression levels was observed in ethylbenzene-treated groups compared with the control group. Similarly, ethylbenzene treatment enhanced protein expression of HO-1 and Nrf2 in a dose-dependent manner. Our results indicated that ethylbenzene induced oxidative stress, apoptosis, and upregulation of HO-1 and Nrf2 in NRK-52E cells, which contributes to ethylbenzene-induced renal toxicity.

Keywords

Ethylbenzene renal toxicity apoptosis oxidative stress heme oxygenase-1

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