Anti-diabetic effects of aqueous prickly lettuce (Lactuca scariola Linn.) leaves extract in alloxan-induced male diabetic rats treated with nickel (II).

BACKGROUND: Hattaraki pallye or prickly lettuce (Lactuca scariola Linn.) is one among several green leafy plants that grow in north Karnataka; it is usually consumed by the people of this region and is found to be antidiabetic in nature. The objective of this study is to evaluate hypoglycemic activities of supplementation with aqueous extract of prickly lettuce (L. scariola) leaves in vivo in acute and subchronic exposure with or without nickel (II) along with its glucose reduction capabilities with or without nickel (II) at pH 7.0 and 9.0 in vitro. METHODS: Percentage glucose reduction (in vitro) was determined by glucose oxidase-peroxidase enzymatic method at pH 7.0 and pH 9.0 using UV-Vis spectrophotometer. Hypoglycemic activities of L. scariola were carried out in alloxan-induced male diabetic rats at both acute and subchronic exposure. RESULTS: The results showed a significant alteration in the λmax value of Ni (II) in combination with L. scariola leaves extracts at both pH 7.0 and 9.0. The aqueous extract also produced a significant reduction in the glucose concentration at pH 7.0 and pH 9.0 even in presence of Ni (II) in vitro. Lactuca scariola leaves in either acute or subchronic supplementation showed a greater glucose tolerance and hypoglycemic regulation of blood sugar in diabetic rats with or without nickel (II) treatments. CONCLUSIONS: Lactuca scariola leaves can be a substitute for synthetic drugs to treat diabetic patients.

α-tocopherol supplementation prevents lead acetate and hypoxia-induced hepatic dysfunction.

OBJECTIVE: Lead (Pb) is a long-known poison of environment and industrial origin. Its prolonged exposure affects cellular material and alters cellular genetics and produces oxidative damages. In this study, we investigated the exposure of chronic sustained hypoxia or lead acetate alone or in combination with or without supplementation of α-tocopherol on hepatic oxidative and nitrosative stress in rats. MATERIALS AND METHODS: The rats weighing 165 ± 5 g were exposed to chronic sustained hypoxia (10% oxygen) or lead acetate (25 mg/kg of body weight, intraperitoneally) alone or in combination with or without supplementation of α-tocopherol (10 mg/100 g b.wt, intramuscularly). The body weight of all the rats was recorded on the day 1 of the treatment and the day of sacrifice. Serum lipid profile was estimated by using a biochemical analyzer. Oxidant and enzymatic antioxidants status was evaluated by using spectrophotometer. Serum levels of hypoxia inducible factor-1 alpha (HIF-1α) and vascular endothelial growth factor (VEGF) were measured by using ELISA technique. Histopathological assessments of hepatic tissue were also done. RESULTS: Exposure of both lead and hypoxia showed decreased body weight, altered serum lipid profile, oxidant and enzymatic antioxidants status, serum HIF-1α and VEGF concentrations. Simultaneous α-tocopherol supplementation showed beneficial effects to all these alterations. Histopathological observations also showed hepatic degenerative changes after lead or hypoxia exposure either alone or in combination, but remarkable improvement has been noticed after α-tocopherol supplementation. CONCLUSION: Supplementation of α-tocopherol is beneficial to counter both lead acetate and hypoxia induced hepatic cytotoxicities possibly by reducing oxidative and nitrosative stress.

α-Tocopherol ameliorates nickel induced testicular oxidative and nitrosative stress in albino rats.

BACKGROUND: Heavy metals generate free radicals and induce oxidative and nitrosative stress with depletion of antioxidants. In this study, we have evaluated the beneficial effects of α-tocopherol against nickel sulfate exposed testicular dysfunction. METHODS: We studied the effect of supplementation of α-tocopherol (10 mg/100 g body weight, i.m.) on nickel sulfate (2.0 mg/100 g body weight, i.p.) induced testicular oxidative and nitrosative stress in Wister strain male albino rats. Serum and testicular nitric oxide, L-ascorbic acid and serum α-tocopherol concentrations were evaluated. We also evaluated sperm count, motility and histopathology of testes. RESULTS: Nickel treated rats showed significantly decreased body weight, testicular somatic index, sperm count, sperm motility, serum and testicular L-ascorbic acid concentration and serum α-tocopherol level as compared to their controls. However, simultaneous treatment with nickel sulfate and α-tocopherol produced a remarkable improvement of all the above parameters when compared with treatment with nickel alone. Nickel treated rats also had significantly increased serum and testicular nitric oxide concentrations as compared to their controls. However, simultaneous treatment with nickel sulfate and α-tocopherol significantly decreased nitric oxide concentrations in both serum and testes, respectively, as compared to nickel treatment alone. Histopathology of the testes revealed tortuous seminiferous tubules, loss of spermatogenesis process (>75%), congestion and necrosis in nickel sulfate treated rats, whereas rats simultaneously treated with nickel sulfate and α-tocopherol had almost normal seminiferous tubules and near normal spermatogenesis as compared to nickel alone treated rats. CONCLUSIONS: Nickel sulfate treatment causes testicular oxidative and nitrosative stress in albino rats, but simultaneous supplementation of α-tocopherol was found to be beneficial in combating against such stresses.