Prophylactic efficacy of Boerhavia diffusa L. aqueous extract in toluene induced reproductive and developmental toxicity in Drosophila melanogaster

Abstract

Background: Environmental exposure to toxicants poses high risk to develop reproductive and developmental chronic toxicity in man. Toluene is one of the commonest industrial agents whose exposure is attributed with potential to induce reproductive and developmental toxicity. Since they contaminate the immediate environment of air and water to which humans are exposed, its containment is of great public health importance. Conventional treatment modalities fail owing to the difficulty to detect these highly volatile agents in environment and human body. The peril of such hazardous exposures is evident only when irreversible structural and functional damages have incurred. In such instances, prevention gains an upper hand when compared to therapeutic interventions. Several natural compounds derived from medicinal herbs possess potential to curb toxicities induced by such xenobiotic agents. Among them Boerhavia diffusa Linn. is a widely distributed and common herb attributed with antitoxic potential and capability for antioxidant defence. A study was performed on the prophylactic efficacy of aqueous extract of B. diffusa in curbing toluene induced developmental toxicity in Drosophila melanogaster. Methods: The study consisted of a preliminary phytochemical screening and HPTLC profiling of B. diffusa aqueous extract (BDAE). LC50 of toluene was assessed and a sublethal dose of 200 ppm was fixed for the study. Four doses of BDAE; 25, 50, 100 and 200 mg/ml designated as Low dose, medium dose 1, medium dose 2 and high dose was used for the study. The parameters used for the study included the determination of larval period, pupal period, percentage of egg hatching, morphometric analysis of egg, larvae, pupae and adults, fertility, fecundity, lifespan and levels of antioxidant enzymes such as catalase, glutathione-S-transferase and superoxide dismutase. Results: The phytochemical and HPTLC characters were as per the pharmacopoeial standards. LC50 of toluene was found to be 430 ppm in this study. BDAE at medium dose 2 and high dose significantly prevented the deterioration of reproductive and developmental toxicity parameters of larval period, pupal period, percentage of egg hatching, morphometric characters of larva, pupa and adult, fertility, fecundity and lifespan in drosophila. Also the drug significantly elevated the levels of antioxidant enzymes. Conclusion: Toluene exposure during lifetime is inevitable. B. diffusa, equipped with its rich active ingredients prevented toluene induced developmental and reproductive toxicity in Drosophila. This medicinal herb provides a ray of hope in preventing environmental toxin induced reproductive and developmental toxicity. Keywords: Developmental toxicity, Reproductive toxicity, Toluene, Boerhavia diffusa, Antioxidant