In vivo potential hypoglycemic and in vitro vasorelaxant effects of Cecropia glaziovii standardized extracts

Abstract

The aim of this study is to investigate the effect of Cecropia glaziovii Snethl, Urticaceae, extracts on theoral glucose tolerance curve, on glycemia in alloxan-induced diabetic rats and vasorelaxant effect after the extraction process, and to standardize the extractive solutions. The effects of the process variablesand their interactions were calculated in relation to dry residue, pH, total phenolic results and chemicalmarker content. Furthermore, the effect of the extracts (400 mg/kg), chlorogenic (2 or 15 mg/kg) andcaffeic acids (2 mg/kg) were investigated on the oral glucose tolerance curve and on glycemia in alloxan-induced diabetic rats. Oral administration of ethanol extracts 4d20 and 8d20 significantly improvedglucose tolerance in the hyperglycemic rats. Chlorogenic and caffeic acids, as well as the association of the compounds were able to significantly reduce glycemia after oral gavage treatments. On the other hand, the aqueous extracts did not alter the glycemia. The aqueous extracts (8020 and 9030) and only the higher dose of chlorogenic acid presented a significant effect on serum glucose lowering in diabeticrats. Additionally, the IC50 reveals that the ethanol extracts presented more potent vasodilator effectsthan the aqueous extracts in aortic rings. This study shows that C. glaziovii standardized extracts exhibit santihyperglycemic action, is able to improve glucose tolerance and has a potent vascular relaxing effect. These results are probably linked to concentrations of the main phenolic compounds of the extracts.