ABSTRACT Diabetes mellitus is a syndrome that reaches more than 382 million people worldwide. It interferes with the metabolism of carbohydrates, causing chronic hyperglycemia. The objective of this study was to evaluate the effect of the Copaifera duckei, Dwyer, Fabaceae, oleoresin on streptozotocin-induced (STZ) diabetic rats. This study was based on the induction of diabetes mellitus by streptozotocin (55 mg/kg, i.p.) in Wistar rats and treated with doses of C. duckei oleoresin (250 and 500 mg/kg, p.o.). Subsequently, the clinical, biochemical and histopathological of the pancreas parameters were evaluated. Gas chromatographic analysis indicated that β-bisabolene (22.29%), β-caryophyllene (21.25%) and α-farnesene (15.58%) sesquiterpenes were the major components of the C. duckei oleoresin. In streptozotocin-induced diabetes mellitus, it was possible to observe that the C. duckei oleoresin treatment had a significant effect (p < 0.001) on the clinical parameters, and that there was a positive improvement. This was attenuated by the urea, creatinine, and transaminases alterations (p < 0.001) observed in animals with diabetes mellitus, as well as the significantly reduced (p < 0.001) values of total cholesterol, triacylglycerides, and glucose. In the histopathological analyses of the pancreas, it was observed that the C. duckei oleoresin was able to restore β-cells and to significantly increase the quantity and diameter of the Langerhans islets (p < 0.05), when compared to the diabetic group. The treatment with C. duckei oleoresin, employed under the conditions of this study, presented antidiabetic activity and can improve the complications found in this syndrome.

ABSTRACT Diabetes mellitus is a chronic and severe metabolic dysfunction, it's slow and progressive evolution interferes directly in the metabolism of carbohydrates, fats and proteins, causing hyperglycemia, glycosuria, polydipsia, hyperlipidaemia, among others. The aim of this study was to evaluate the antidiabetic effect of hydroethanolic extract and granulated of Calophyllum brasiliense Cambess., Clusiaceae, species in diabetic rats as well as it's biochemical parameters. The results demonstrated that both the pharmaceutical forms, hydroethanolic extract and granulated, were able to reduce significantly (p < 0.001) hyperglycemia and glycosuria, in addition to improve polydipsia, polyuria, and weight loss. Treatments using hydroethanolic extract and granulated were also able to reduce significantly levels of triacylglycerides, cholesterol and low-density lipoprotein, as well as the transaminases, urea and creatinine levels. Therefore, it is concluded that these pharmaceutical forms have anti-diabetic effect and act improving the biochemical parameters, this effect is probably due to the high content of polyphenolic compounds found in the formulations.