Hyptis verticillata attenuates dyslipidaemia, oxidative stress and hepato-renal damage in streptozotocin-induced diabetic rats.

AIMS: Chronic hyperglycaemia in diabetes mellitus (DM) increases the production of free radicals which results in oxidative stress and related disorders such as cardiovascular diseases, compromised hepatic and renal functions. Hyptis verticillata reportedly demonstrated glucose lowering activity in previous studies. The present study therefore evaluated the effect of H. verticillata on hyperglycaemia-induced dyslipidaemia, hepatorenal distortions, oxidative stress, as well as calculated indices of cardiovascular function. METHODS: Wistar rats employed for this study consisted of normoglycaemic and diabetic rats in nine experimental groups. The normoglycaemic and diabetic rats were either treated with metformin (500 mg/kg b.w.), quercetin (10 mg/kg b.w.), or ethanol extract of H. verticillata leaf (250 mg/kg b.w. and 500 mg/kg b.w.) administered orally for 28 days. KEY FINDINGS: Results revealed that H. verticillata significantly lowered blood glucose level, attenuated dyslipidaemia, decreased atherogenic coefficient, atherogenic and coronary risk indices, and increased cardioprotective index in diabetic rats. Also, H. verticillata significantly decreased serum urea, creatinine, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and unconjugated bilirubin levels, relative to untreated diabetic rats. Further, H. verticillata increased serum superoxide dismutase, catalase and glutathione peroxidase activities and glutathione level, and decreased malondialdehyde level in diabetic rats in a manner similar to metformin and quercetin. Histopathological investigation of the liver and kidney revealed restored hepatocytes and amelioration of congested interstitial blood vessel of the Bowman's space of the kidneys upon intervention with H. verticillata. SIGNIFICANCE: H. verticillata in addition to its anti-hyperglycaemic activity ameliorates oxidative stress, dyslipidaemia, atherogenicity and hepatorenal lesions in DM.

Activity of crude cold-water extract of the culinary-medicinal oyster mushroom, Pleurotus ostreatus (Jacq.:Fr.) P.Kumm. (higher Basidiomycetes), and timolol maleate on induced ocular hypertension.

Aqueous crude cold-water extract from the fruiting body of the culinary-medicinal oyster mushroom Pleurotus ostreatus was assessed for activity against increased intra-ocular pressure (IOP) in mice. A 0.1% dexamethasone instillation was used to raise the intra-ocular pressure in the animals above the 21-mmHg threshold limit. The extract has intrinsic anti-hypertensive properties that are dose dependent. A comparison analysis indicated that 150 mg/mL of the crude extract produced 57.69% reduction in the intra-ocular pressure, while doses of 100 mg/ mL and 200 mg/mL produced 44.78% and 70.03% IOP reduction, respectively, compared with timolol maleate with 57.69%. The results were significant at 0.05 confidence limit (p < 0.05) when compared to a placebo and therefore support its use for the treatment of increased intra-ocular pressure.