Bioprospecção de extratos de quimiotipos de Myracrodruon urundeuva: atividade antiinflamatória

Abstract

Inflammation is a complex physiological response to potentially harmful stimuli and can lead to diseases when it is exacerbated. Medicinal plants are an alternative for the treatment of this disorder, as M. urundeuva (MU), commonly used for this purpose. In this study, we have analyzed the anti-inflammatory effect and the antioxidant and cytotoxic activity of extracts of leaves of MU chemotypes (myrcene, α-pinene, Δ3 -carene and limonene) collected in Rio Grande do Norte/Brazil. Moreover, we investigated the anti-inflammatory activity of extracts from the stem bark of “aroeira”. To evaluate its anti-inflammatory potential, we investigated the action on the release of myeloperoxidase (MPO) in human neutrophils and the effect on the volume of paw edema induced by carrageenan in mice. The evaluation of the antioxidant activity was made by using the DPPH (2,2-diphenyl-1-picrylhydrazyl hydrate) test. By determining the toxicity on the cell membrane, we measured the activity of cytosolic lactate dehydrogenase present in the medium. When testing their action on the release of MPO, all extracts of the leaves of MU chemotypes showed inhibition of the order of 46-80%, considering the maximum release of the control group (100%). The ethanolic extract of the leaves of MU myrcene chemotype was the only one that showed significant toxicity to the membrane of neutrophils. The ethanolic extract of the leaves of MU á-Pinene chemotype (MUPFh-E) (400 mg/kg body weight) and the dry extract of the stem bark (800mg/Kg body weight) were able to reverse the edema in the 2nd, 3rd and 4th hours after induction. The remaining ethanolic extracts of the stem bark tested did not decreased the paw edema at the concentrations evaluated. In the antioxidant activity test, all tested extracts were equivalent to standard (vitamin-E 100ìg/mL) from the concentration of 25ìg/mL. The results of this study demonstrated both the in vitro and in vivo anti-inflammatory potential of MUPFh-E, as well as its antioxidant activity, suggesting that the bioactivity of extracts from “aroeira” may vary depending on the extraction method and the plant chemotype.