PROTECTIVE EFFECT OF HYDROALCOHOLIC EXTRACT OF GLORIOSA SUPERBA LINN. IN LEAD INDUCED NEUROTOXICITY IN RATS

V. Uma Rani*, M. Sudhakar, A. Ramesh, B.V.S.Lakshmi, Yengala Srinivas

In the present study, tubers of Gloriosa superba Linn (Liliaceae) was selected for evaluating the effect of hydroalcoholic extract of Gloriosa superba Linn in lead induced neurotoxicity in rats. Thirty six wistar rats (150- 200g) were selected and divided into six groups of six in each. Group I (normal control) received distilled water, group II-lead nitrate (10 mg/kg, p.o.), group III-lead nitrate + vitamin E (10 mg/kg, p.o. + 100 mg/kg, p.o.), group IV-lead nitrate + HEGS (10 mg/kg, p.o. + 50 mg/kg, p.o.), group V-lead nitrate + HEGS (10 mg/kg, p.o. + 100 mg/kg, p.o.), group VI-lead nitrate + HEGS (10 mg/kg, p.o. + 200 mg/kg, p.o.) experiment was carried out for 21 days. At end of the experiment various behavioral, biochemical and histopathological assessments were carried out. The animals showed increase in transfer latencies indicating learning and memory implairment in lead control group, but administration of hydroalcoholic extract of Gloriosa superba Linn decreased the transfer latencies, strengthened its memory improvement action in drug treated animals. Hence showed decrease in muscle strength measured by rota-rod test whereas, in hydroalcoholic extract of Gloriosa Superba Linn treated group there was improvement in muscle strength. The locomotor activity assessed by actophotometer and open field test was decreased in lead nitrate group compared with hydroalcoholic extract of Gloriosa superba Linn treated group. Biochemical analysis of brain revealed that the chronic administration of lead nitrate significantly increased lipid peroxidation and decreased levels of catalase (CAT), reduced glutathione (GSH) and glutathione reductase (GR), an index of oxidative stress process. Administration of hydroalcoholic extract of Gloriosa superba Linn attenuated the lipid peroxidation and reversed the decreased brain CAT and GSH levels. Lead exposed rats showed increased levels of various serum parameters like glucose, ALT, ALP, TG and TC. Lead toxicity also leads to alteration in acetylcholinesterase levels, might have caused neurobehavioral changes which was measured by the change in acetylcholinesterase activity but prior administration of hydroalcoholic extract of Gloriosa superba Linn ahead of lead nitrate ameliorated the change. There was marked changes at the subcellular level which were observed by histopathology studies in lead treated group and better improvement in these changes was observed in hydroalcoholic extract of Gloriosa superba Linn treated group. Therefore hydroalcoholic extract of Gloriosa superba Linn helps to combat the oxidative stress produced by the accumulation of lead in the body.