Comparative evaluation of hypoglycemic and hypolipidemic activity of various extract of Anogeissus latifolia bark in streptozotocin-induced diabetic rats.

Background Anogeissus latifolia Wall. (A. latifolia) bark has been traditionally used in the treatment of various diseases which includes diabetes and general debility. The present study was aimed to investigate the comparative hypoglycemic and hypolipidemic activity of various extracts of A. latifolia bark in streptozotocin-induced type 1 diabetic rats. Methods Acute toxicity was carried out at 2 g/kg dose of petroleum ether extract of A. latifolia bark (PEALB), chloroform extract of A. latifolia bark (CEALB) and methanol extract of A. latifolia bark (MEALB) in rats. Diabetes was induced by streptozotocin (STZ, 60 mg/kg, i.p.) and it was confirmed at 72 h. Diabetic rats received above extracts at 100 and 200 mg/kg doses for 28 days. Body weight and blood glucose level were determined at every week after the treatment schedule. Serum biochemical parameters and lipid profile levels were estimated at the end of the study. Results PEALB, CEALB and MEALB were non-toxic and no death was observed at 2 g/kg dose. Administration of MEALB at 100 and 200 mg/kg showed significant (p< 0.01, p< 0.05) improvement in body weight and reduction in blood glucose at third and fourth week of treatment. Altered serum biochemical parameters and lipid profiles level were brought to near normal level significantly (p<0.001) compared to diabetic control rats after the administration of both doses of MEALB. However, PEALB and CEALB did not exhibit significant hypoglycemic and hypolipidemic activity. Conclusions Our findings revealed that long-term (28 days) treatment of MEALB possesses significant hypoglycemic and hypolipidemic activity compared to PEALB and CEALB in type 1 diabetic rats and given evidence to the traditional use of A. latifolia bark in diabetes.

Virtual Screening Analysis and In-vitro Xanthine Oxidase Inhibitory Activity of Some Commercially Available Flavonoids.

Allopurinol, the xanthine oxidase inhibitor, is the only drug available for the treatment of gout. We examined the xanthine oxidase inhibitory activity of some commercially available flavonoids such asepigallocatechin, acacatechin, myricetin, naringenin, daidzein and glycitein by virtual screening and in-vitro studies. The interacting residues within the complex model and their contact types were identified. The virtual screening analysis were carried out using AutoDock 4.2 and in-vitro xanthine oxidase inhibitory activity was carried out using xanthine as the substrate. In addition, enzyme kinetics was performed using LineweaverBurkplot analysis. Allopurinol, a known xanthine oxidase inhibitor was used as the standard. The docking energy ofglycitein was found to be -8.49 kcal/mol which was less than that of the standard (-4.47 kcal/ mol). All the selected flavonoids were found to exhibit lower binding energy (-8.08 to -6.03 kcal/ mol) than allopurinol. The docking results confirm that flavonoids showed greater inhibition of xanthine oxidase due to their active binding sites and lesser binding energies compared to allopurinol. This may be attributed to the presence of benzopyran ring in the flavonoids. In the xanthine oxidase assay, IC50 value of glycitein was found to be 12±0.86 µg/mL, whereas that of allopurinol was 24±0.28 µg/mL. All the remaining compounds exhibited IC50 values ranging between 22±0.64 to 62±1.18 µg/mL. In the enzyme kinetic studies, flavonoids showed competitive type of enzyme inhibition. It can be concluded that flavonoids could be a promising remedy for the treatment of gout and related inflammatory disorders. Further in-vivo studies are required to develop potential compounds with lesser side effects.

Protective effect of the leaves of Vitex negundo against ethanol-induced cerebral oxidative stress in rats.

The present study investigated the effect of the various fractions of hydromethanolic extract of the leaves of Vitex negundo (Verbenaceae) against ethanol-induced cerebral oxidative stress in rats. Cerebral oxidative stress was induced by the administration of 20% ethanol (5 ml/100 gbw) for a period of 28 days. The petroleum ether (PEF), chloroform (CF), ethylacetate (EAF) and residual (RF) fractions at a dose of 200 mg/kgbw orally were simultaneously administered with ethanol for 28 days. α-tocopherol at a dose of 100 mg/kg orally was used as the standard. Administration of ethanol resulted in a significant elevation in serum biochemical parameters like aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), uric acid, triglycerides and lipoprotein levels. In addition there was a significant (P<0.01) elevation in malondialdehyde (MDA) and lipid hydroperoxide (LH) levels and a significant (P<0.01) reduction in enzymatic and non-enzymatic antioxidants in the brain tissue. Histopathological examination of the brain tissue of the ethanol treated animals showed marked gliosis. Simultaneous administration of the fractions prevented the enzymatic leakage and elevation of serum uric acid, triglycerides and lipoprotein levels. All the fractions (except the residual fraction) prevented the rise in lipid peroxidation and enhanced the antioxidant enzymes. Further, histopathological examination revealed that the fractions of V. negundo offered a significant protection against ethanol toxicity in rat brain. The activity exhibited by the chloroform fraction is comparable to that of the standard. The present study reveals that the leaf of V negundo has protective action on the brain, which could be attributed to its antioxidant potential.

In vitro antioxidant activity of Vetiveria Zizanioides root extract.

Free radicals induce numerous diseases by lipid peroxidation and DNA damage. It has been reported that some of the extracts from plants possess antioxidant properties capable of scavenging free radicals in vivo. Vetiveria zizanioides belonging to the family Gramineae, is a densely tufted grass which is widely used as a traditional plant for aromatherapy, to relieve stress, anxiety, nervous tension and insomnia. In this regard, the roots of V zizanioides was extracted with ethanol and used for the evaluation of various in vitro antioxidant activities such as reducing power ability, superoxide anion radical scavenging activity, deoxyribose degradation assay, total antioxidant capacity, total phenolics and total flavonoid composition. The various antioxidant activities were compared with suitable antioxidants such as butyl hydroxy toluene, ascorbic acid, quercetin, alpha tocopherol, pyrocatechol and curcumin respectively. The generation of free radicals O2, H2O2 OH and N O were effectively scavenged by the ethanolic extract of V zizanioides. In all these methods, the extract showed strong antioxidant activity in a dose dependent manner. The results obtained in the present study clearly indicates that V zizanioides scavenges free radicals, ameliorating damage imposed by oxidative stress in different disease conditions and serve as a potential source of natural antioxidant. The study provides a proof for the ethnomedical claims and reported biological activities. The plant has, therefore, very good therapeutic and antioxidant potential.

Xanthine oxidase inhibitory activity of some Indian medical plants.

Xanthine oxidase inhibitory activity was assayed from six species belonging to different families traditionally used for the treatment of gout and related symptoms by indigenous people of India. The aqueous, methanol-water mixture and methanolic extract of these plants were used for the experiment. Of the 18 extracts assayed, 14 extracts demonstrated xanthine oxidase inhibitory activity at 100 microg/ml, among which 10 extracts showed an inhibition greater than 50% and IC(50) values below 100 microg/ml. The methanolic extracts of Coccinia grandis, Datura metel, Strychnos nux-vomica and Vitex negundo showed more than 50% inhibition, hence, they were screened for their in vivo hypouricaemic activity against potassium oxonate-induced hyperuricaemia in mice. Methanolic extracts of Coccinia grandis and Vitex negundo showed a significant decrease in the serum urate level (3.90+/-0.07 mg/dl, P<0.001) and (6.26+/-0.06 mg/dl, P<0.01), respectively, when compared to hyperuricaemic control (11.42+/-0.14 mg/dl). This effect is almost similar to the serum urate level of allopurinol (3.89+/-0.07 mg/dl).