Avaliação da atividade hipoglicêmica do oleo essencial de folhas de Piper marginatum em camundongos

Abstract

Diabetes Mellitus is the fastest growing chronic condition, especially in developing countries. Considering the growing number of diabetes cases, high costs related to its control, treatment of its complications, numerous side effects caused by oral and injectable medications and by the Piper marginatum species being incident in the region, this study aimed to evaluate the oil's hypoglycemic activity of leaves of P. marginatum in mice. The dissertation project was submitted to the Ethics Committee on the Use of Animals at UFOPA - CEUA / UFOPA and was approved under protocol No. 1120180048/2019. For the evaluation of acute oral toxicity, 12 female mice, isogenic from the Swiss strain, were submitted to the experiment, which were divided into a control group and a test group in which they received the essential oil (OE) of levaes from P. marginatum in a single concentration of 2000mg / kg and observed for 14 days, following the protocol OECD 423/2001.To verify the action of the OE of P. marginatum, glycemic levels were measured in 36 male Swiss mice and concentrations of 100 mg / kg, 200 mg / kg and 400 mg / kg administered by gavage for 20 days. Blood glucose, water and feed intake, body weight and biochemical parameters were evaluated. The OE was obtained by hydrodistillation in Clevenger apparatus and chemical characterization by gas chromatography coupled to mass spectrometry (CG-EM). In the chemical composition, a total of forty-three compounds were identified, the major ones being: 3-Carene (13.28%), followed by Karyophylene (12.57%), Copaene (9.50%), 3,4-methylenedioxypropiophenone (7.96%), Elixene (6.02%), β-Cubebene (5.60%). Regarding acute oral toxicity, the mice showed body weight gain and absence of symptoms or clinical signs of intoxication and death. In the glycemic evaluation, the OE of leaves from P. marginatum did not show antidiabetic activity as it maintained hyperglycemia in the mice treated with the oil until the end of the experiment. In addition, during the 20 days the mice showed polydipsia, polyphagia and weight loss. In the biochemical evaluation, Alanine aminotransferase (ALT) and creatinine showed no significant changes, with the exception of urea, which presented values 2.2 times higher in relation to the nondiabetic control group. The hepatic marker Aspartate aminotransferase (AST) of the animals treated with the OE of leaves from P. marginatum gradually decreased as the dose in mg / kg was increased. These results showed that although the OE of leaves from P. marginatum did not have a satisfactory effect in reducing glycemia in experimental models, it is believed that the results of this research contributed to the toxicological knowledge of the species studied, as it did not demonstrate toxicity when administered orally. Therefore, it is necessary to invest in more experimental studies with an in vitro approach in order to identify biological potential and complement the information presented in this study.