Infuso das folhas da guavira (Campomanesia pubescens (d.c.) O. berg): estudo fitoquímico, toxicidade préclínica e efeitos biológicos em ratos wistar

Abstract

Plants continue to be an essential source of bioactive compounds, and their study requires a multidisciplinary approach that combines ethnobotanical, phytochemical, and biological techniques to identify new compounds with therapeutic purposes. Popularly known as guavira, Campomanesia pubescens (D.C.) O. Berg is a fruit plant, the symbol of Mato Grosso do Sul, which has shown promise in terms of therapeutic properties and biological effects, reported by ethnopharmacological use and identified by studies as flavonones and chalcones, including 2',4'-dihydroxy-3',5'-dimethyl-6' methoxyalcone. However, no studies were found in the literature regarding its toxicity and biological effects (renal and antihyperglycemic agents). Thus, this work aimed to carry out a phytochemical study, assessment of toxicity, mutagenicity, and biological effects of the infusion of leaves of C. pubescens. For the acute toxicity test, 10 female Wistar rats received a single dose of 2000 mg/kg body weight of C. pubescens tea by gavage and were observed for 14 days. For subacute toxicity, male and female Wistar received repeated doses of 15, 40 and 250 mg/kg of body weight of C. pubescens tea orally, being treated and observed for 28 days and, after this period of treatment, a group satellite and satellite control remained under observation for another 14 days. To verify the renal effects, the same male rats used in the subacute toxicity test were evaluated on day zero and on the 28th day of the experiment. Results were evaluated by permutational multivariate analysis of variance (Permanova). When a significant difference was found between the groups, non-metric multidimensional scaling (nMDS) and principal component analysis (PCA) were used, followed by the Bonferroni test. In the acute toxicity assay, the LD50 was estimated to be greater than 2000 mg/kg. In long-term toxicity, the doses tested did not produce significant changes in physiological, behavioral, hematological or histopathological parameters in the animals. Therefore, it did not exhibit acute and subacute toxicity, being classified as grade V, that is, it presents a low risk of toxicity. The tea had a renal effect with increased relative urinary volume from day 0 to day 28. However, no antihyperglycemic effects were observed. The phytochemical profile of C. pubescens tea indicated high levels of flavonoids, antibacterial (MIC), and antioxidant activity. It is recommended that new studies of tea from the leaves of C. pubescens be carried out to elucidate the mechanism of action on the renal effects and verify the toxicity in repeated doses with prolonged exposure greater than 28 days.