Pyruvate modulates antioxidant status of cultured human lens epithelial cells under hypergalactosemic conditions

Lens epithelial cells are the metabolic unit of the lens and antioxidant enzymes are mainly concentrated here. The purpose of this study was to maintain human lens epithelial cells (HLEC) in culture and examine the status of antioxidant enzymes (glutathione peroxidase (GSHPx), catalase (CAT), glutathione-S-transferase (GST)), lipid peroxidation product malondialdehyde (MDA) and glutathione (GSH) levels in these cells under normal as well as hypergalactosemic (30 mM galactose) conditions. Further, effect of pyruvate, a physiological antioxidant has also been evaluated on these parameters. For conducting experiments, anterior capsule specimens obtained from fresh cadaver eyes from eye bank were cultured in Dulbecco's Modified Eagle's Medium (DMEM) supplemented with 20% fetal calf serum. Upon confluency, the cells were subcultured in three separate flasks containing DMEM alone (normal group), DMEM + 30 mM D-galactose (control group), DMEM + 30 mM D-galactose + 5 mM pyruvate (test group) and incubated for 24 or 72 h. These cells were observed under the phase contrast microscope for any morphological changes and harvested for the estimation of various antioxidant parameters. Our results show significant weakened antioxidant defense in HLEC when incubated in the presence of galactose as compared to normal. Addition of pyruvate significantly modulated levels of GSH, MDA, GSHPx, CAT and GST.