Anti-Cataract Potential of Heliotropium indicum Linn on Galactose-Induced Cataract in Sprague-Dawley Rats.

OBJECTIVE: To evaluate the anti-cataract potential of an aqueous whole plant extract of Heliotropium indicum (HIE) on galactose-induced cataract in Sprague-Dawley rats. MATERIALS AND METHODS: Cataract scores were recorded in 3-week-old Sprague-Dawley rats in which cataract was being induced by an oral administration of 1500 mgkg-1 galactose twice daily for 4 weeks, and concurrently being treated with 30, 100, or 300 mgkg-1 HIE daily over the induction period. Fasting blood glucose was monitored at weekly intervals. Changes in body weight as well as total lens protein, lens glutathione, and superoxide dismutase (SOD) were determined initially, and at the end of the experimental period. Crystalline lens weight-to-body-weight ratio was also determined for the various treatment groups at the end of the experimental period. Preliminary phytochemical screening, total antioxidant capacity, and reducing power assays were conducted on HIE. RESULTS: The 30 and 100 mgkg-1 HIE-treated rats recorded significantly lower (p ≤ 0.05-0.001) cataract scores (indicating very significant delays in cataractogenesis by the 3rd and 4th weeks of treatment) and blood glucose levels. Rats with delayed cataractogenesis also exhibited significant (p ≤ 0.05-0.001) weight gain, and reduction in lens weight. Total lens proteins glutathione and SOD levels in the crystalline lens were also significantly preserved (p ≤ 0.01-0.001). HIE showed substantial antioxidant capacity and reducing power. CONCLUSION: The aqueous whole plant extract of Heliotropium indicum delays cataractogenesis at an optimum dose of 30 mgkg-1 in Sprague-Dawley rats.

The Claim of Anti-Cataract Potential of Heliotropium indicum: A Myth or Reality?

INTRODUCTION: Heliotropium indicum has several uses in traditional medicine attributable to its numerous bioactive compounds. It is used as a traditional remedy for cataracts in Ghana without any scientific verification. This study aimed at verifying the anti-cataract properties of an aqueous whole plant extract of H. indicum. METHODS: The effect (cataract score) of 30, 100, and 300 mg kg(-1) extract (bid for 21 days, per os) on the development of 30 µmol kg(-1) sodium selenite-induced cataract in 10-day-old rat pups was investigated. Soluble lens proteins alpha A and alpha B crystallins, total lens protein, total lens glutathione, and aquaporin 0 in enucleated lens homogenates were determined spectrophotometrically using commercially available kits. Histopathological studies on the lenses were also performed. The 2,2-diphenyl-1-picrylhydrazyl scavenging effect and linoleic acid autoxidation (antioxidant properties) of the extract (0.1-3.0 mg ml(-1)), compared to n-propyl gallate, were ascertained using standard procedures. RESULTS: Cataract scores showed that the extract, at all dose levels, significantly alleviated selenite-induced cataracts (P ≤ 0.001). Markers of lens transparency (aquaporin 0, alpha A and B crystallins), as well as total lens proteins and lens glutathione levels, were significantly preserved (P ≤ 0.01-0.001). The extract exhibited activity relevant for scavenging free radicals and inhibition of lipid peroxidation. Epithelial and lens fiber integrity in the histopathological assessment were maintained with HIE treatment. CONCLUSION: The aqueous whole plant extract of H. indicum significantly inhibited the development of cataracts in rats via multiple mechanisms.