Selenite and ebselen supplementation attenuates d-galactose-induced oxidative stress and increases expression of SELR and SEP15 in rat lens

Selenite and ebselen supplementation has been shown to possess anti-cataract potential in some experimental animal models of cataract, however, the underlying mechanisms remain unclear. The present study was designed to evaluate the anti-cataract effects and the underlying mechanisms of selenite and ebselen supplementation on galactose induced cataract in rats, a common animal model of sugar cataract. Transmission electron microscopy images of lens fiber cells (LFC) and lens epithelial cells (LEC) were observed in d-galactose-induced experimental cataractous rats treated with or without selenite and ebselen, also redox homeostasis and expression of proteins such as selenoprotein R (SELR), 15kD selenoprotein (SEP15), superoxide dismutase 1 (SOD1), catalase (CAT), β-crystallin protein, aldose reductase (AR) and glucose-regulated protein 78 (GRP78) were estimated in the lenses. The results showed that d-galactose injection injured rat lens and resulted in cataract formation; however, selenite and ebselen supplementation markedly alleviated ultrastructural injury of LFC and LEC. Moreover, selenite and ebselen supplementation could mitigate the oxidative damage in rat lens and increase the protein expressions of SELR, SEP15, SOD1, CAT and β-crystallin, as well as decrease the protein expressions of AR and GRP78. Taken together, these findings for the first time reveal the anti-cataract potential of selenite and ebselen in galactosemic cataract, and provide important new insights into the anti-cataract mechanisms of selenite and ebselen in sugar cataract.