Protective effect of alpha-lipoic acid on progression of cataract formation in fructose-induced experimental cataract

Abstract

Cataract is the leading cause of ocular blindness worldwide and exacerbated by various systemic disorders, including diabetes and hypertension. The present study was designed to investigate the protective effects of alpha-lipoic acid (LA) against fructose-induced experimental cataract. Sprague-Dawley albino rats (150–180g) were assigned to groups each containing six animals. Group I (normal) received 0.3% carboxymethyl cellulose (10ml/kg/day, p.o.) by gavage. Group II (fructose control) received carboxymethyl cellulose by gavage and 10% (w/v) fructose solution in place of drinking water. Group III and IV received LA at two dose levels 20 and 40mg/kg/day orally by gavage respectively, concurrent with fructose solution (10% w/v) for eight consecutive weeks. Mean arterial pressure, blood glucose level, and lenticular opacity were examined biweekly and pathophysiological parameters in eye lenses were evaluated after eight weeks of the experimental protocol. The eight weeks administration of LA (20 and 40mg/kg) concurrent with fructose solution significantly reduced the mean arterial pressure and blood glucose level. Additionally, lipoic acid treatment led to significant alleviation in lens antioxidants (CAT, SOD, GPx, and GSH), total protein, and Ca2+ ATPase activity. Moreover, a significant reduction in lens MDA and Ca2+ was seen as compared to fructose control group. Ophthalmoscope observations indicated that LA treatment delayed the onset and progression of cataract against the fructose treatment. The results suggest that alpha-lipoic acid supplement play a beneficial role in the management of diabetes and hypertension associated cataractogenesis.