Antidiabetic potential of polyphenolic-rich fraction of Tamarindus indica seed coat in alloxan-induced diabetic rats.

Background: Tamarindus is a monotypic genus and belongs to the subfamily Caesalpinioideae of the family Leguminosae (Fabaceae), Tamarindus indica L., commonly known as Tamarind tree is one of the most important multipurpose tropical fruit tree species in the India, Sudan, Nigeria, Bangladesh and entire subcontinent.

Methods: Hydroethanolic seed coat extract of Tamarindus indica (HETI) was assessed for presence of phytoconstituents and selection of optimum dose through acute and sub acute toxicity study. The single and multidose (14 days) study were conducted to evaluate antidiabetic potential of HETI in alloxan induced rats via determine of blood glucose level, body weight, hematological profile, extra-pancreatic glucose utilization of isolated rat hemi-diaphragm as well as histopathology of rat pancreas.

Results: Phytochemical analysis of HETI showed the presence of polyphenol like flavonoids. Single and multidose of HETI significantly (p<0.05; p<0.001) reduced blood glucose level in normoglycaemic, glucose loaded and alloxan induced hyperglycaemic animals. HETI exerts the protective effect on pancreatic β-cells as per results obtained from histopathology of animals. Moreover, HETI increased glucose uptake in isolated rat hemi-diaphragm and prevents decrease in body weight along with recovery of altered hematological parameters.

Conclusions: The study revealed that HETI have potent hypoglycaemic action by virtue of its phytoconstituents and it can be used as a herbal medicine for diabetes.