Polyherbal formulation containing antioxidants may serve as a prophylactic measure to diabetic cataract: Preclinical investigations in rat model

Abstract

Background: Cataract is a major cause of visual impairment in diabetic patients. Due to increasing numbers of type 1 and type 2 diabetics worldwide, the incidence of diabetic cataracts steadily rises. Cataract surgery is the best possible cure for patients suffering from this ailment. However, the elucidation of pathomechanisms to delay or prevent the development of cataract in diabetic patients remains a challenge. Objective: The aim of the present study was to develop a polyherbal eyedrops containing potent antioxidant herbal extract and study the effectiveness as prophylactic treatment against galactose-induced diabetic cataract. Materials and Methods: Formulations were prepared by using extracts of Ginkgo biloba leaves, beet root (Beta vulgaris), and amla (Emblica officinalis) fruits. The viscosity enhancers were used to increase the retention time. Formulations (F1–F5) were prepared by using carboxy methyl cellulose and poly ethylene glycol-400 as thickening agents and propylene glycol as a solubilizer. Preliminary evaluation showed that formulations have passed clarity, sterility, and eye irritancy tests. Viscosity and pH of formulation were within the normal range. Diabetic cataract was induced in Wistar rats by 10% galactose drink (for 30 days) and anticataract activity was evaluated. Formulation was installed in eye as a prophylactic treatment from day 1 of galactose drinking and continued for 30 days. Results: Slit-lamp photography of eyes of rats showed clear lens of rats without any trace of opacity. On the other hand, galactose-treated rats developed dense nuclear opacity in lens as an indication of diabetic cataract. Rats which received prophylactic treatment showed less percent opacity as compared to that of cataract control group and decreased vacuoles. Conclusion: We may conclude that polyherbal formulation containing extracts of Ginkgo biloba leaves, beet root (Beta Vulgaris), and amla (Emblica officinalis) fruits may prevent the development of cataract in diabetic patients. Abbreviations used: ARI: Aldose reductase inhibitors; GPx: Glutathione peroxidase; GR: Glutathione reductase; DTNB: Dithio-bis-nitrobenzoic acid; GSH: Thiol.