Hypoglycaemic activity ofSpathodea campanulata stem bark decoction in mice

Management of diabetes in Guinean traditional medicine: an ethnobotanical investigation in the coastal lowlands

ETHNOPHARMACOLOGICAL RELEVANCE

This survey was carried out in the coastal lowlands of Guinea-Conakry in order to make an inventory of plants used by traditional healers, herbalists and diabetic patients for the management of diabetes mellitus.

MATERIALS AND METHODS

Frequent ethnomedical and ethnobotanical investigations were conducted from June 2008 to December 2009 in Conakry, Kindia, Forécariah, Dubréka, Boke, Fria and Boffa. It is a cross-sectional survey and data collection is based on the interactive method. During this period a total of 112 people aged from 39 to 76 years old were interviewed.

RESULTS

During this investigation 146 plant species belonging to 55 families were collected. The most cited plants were Anacardium occidentale L. and Ficus spp., while the Fabaceae family was the most represented, followed by the Euphorbiaceae and Rubiaceae. The most frequently plant parts used by the traditional healers and the herbalists were the stem-bark and decoctions the most common preparation mode.

CONCLUSIONS

It is clear that a variety of plants is used in the management and treatment of diabetes. Due to the increasing prevalence of type 2 diabetes, there is an urgent need for scientific investigations to rationalise the use of these traditional remedies, which could represent accessible alternative medicines for the Guinean populations.

In Vitro evaluation of effects of two ghanaian plants relevant to wound healing

Commelina diffusa and Spathodea campanulata are used as wound-healing agents in Ashanti traditional medicine in Ghana. The methanol extracts of Commelina diffusa herb and Spathodea campanulata bark showed some level of antimicrobial activity with C. diffusa exhibiting selective antifungal activity against Trichophyton species. The extracts reduced the peroxidation of bovine brain extract with an IC(50) value of 1.39 mg/mL and 0.24 mg/mL, respectively. In addition the extracts also exhibited significant antioxidant activity by protecting MRC-5 cells from hydrogen peroxide induced oxidant injury at concentrations between 1 microg/mL and 10 microg/mL. The extracts showed no inhibition of NF-kappaB at 100 microg/mL. The antioxidant activities and antimicrobial activities suggest that the use of the plants in wound healing may be based on antioxidant and antiseptic effects of its constituents.

Effect of Aegle marmelos fruits on normal and streptozotocin-diabetic Wistar rats

The present study evaluates the antidiabetic effect of an aqueous extract of Aegle marmelos fruits (AMFEt) in diabetes. Female albino Wistar rats were randomly divided into five groups: normal (untreated), normal + AMFEt, streptozotocin (STZ)-treated, STZ-treated + AMFEt, and STZ-treated + glibenclamide. Rats were rendered diabetic by STZ (45 mg/kg) administered intraperitoneally. AMFEt (250 mg/kg) was given twice daily for 1 month. Blood glucose, plasma insulin, glycosylated hemoglobin, liver glycogen, and change in body weight were determined. Food intake and water intake were monitored daily. An oral glucose tolerance test was also performed to determine the effect of this extract. The results show that glucose level and glycosylated hemoglobin were increased and plasma insulin and liver glycogen were decreased in diabetic rats, and that treatment with AMFEt reversed the effects of diabetes on these biochemical parameters to near-normal levels.

Effect of Gymnema montanum on blood glucose, plasma insulin, and carbohydrate metabolic enzymes in alloxan-induced diabetic rats

The effects of Gymnema montanum, an endangered plant used in the ancient period of India, on blood glucose, plasma insulin, and carbohydrate metabolic enzymes were studied in alloxan diabetic rats. Administration of alcoholic extract of G. montanum leaves (50, 100, 200 mg/kg body weight) to alloxan diabetic rats for 3 weeks reduced the blood glucose level. Administration of G. montanum leaf extract (GLEt) at 200 mg/kg body weight significantly decreased the blood glucose levels and significantly increased the plasma insulin levels. This clearly shows the antidiabetic efficacy of GLEt, which was better than that of glibenclamide.

Effects of Averrhoa bilimbi leaf extract on blood glucose and lipids in streptozotocin-diabetic rats

The present study was designed to investigate the hypoglycemic and hypolipidemic activities of an ethanolic extract of Averrhoa bilimbi Linn. leaves (Oxalidaceae, Common name: Bilimbi) in streptozotocin (STZ)-diabetic rats. The optimal hypoglycemic dose (125 mg kg(-1)) was determined by performing the oral glucose tolerance test (OGTT) in both normal and STZ-diabetic rats. To investigate the effect of repeated administration of an ethanolic extract of Averrhoa bilimbi (ABe) leaves, diabetic rats were treated with vehicle (distilled water), ABe (125 mg kg(-1)) or metformin (500 mg kg(-1)) twice a day for 2 weeks. Like metformin, ABe significantly lowered blood glucose by 50% and blood triglyceride by 130% when compared with the vehicle. ABe also significantly increased the HDL-cholesterol concentrations by 60% compared with the vehicle. ABe thus significantly increased the anti-atherogenic index and HDL-cholesterol/total cholesterol ratio. However, like metformin, ABe did not affect total cholesterol and LDL-cholesterol concentrations, but significantly reduced the kidney lipid peroxidation level. These data show that ABe has hypoglycemic, hypotriglyceridemic, anti-lipid peroxidative and anti-atherogenic properties in STZ-diabetic rats.

Hypoglycemic, anticomplement and anti-HIV activities of Spathodea campanulata stem bark

Spathodea campanulata stem bark decoction (SCD) has shown hypoglycemic activity in mice. It was separated by column chromatography into different fractions, which were evaluated for their hypoglycemic, anticomplement and anti-HIV activities. The most polar fraction exerted by far the most prominent effect in different biological models.