Propriedades anti-inflamatórias e antioxidantes dos extratos aquosos das folhas de Turnera subulata Sm. E Anacardium occidentale L.

Abstract

Plant extracts are widely applied in popular medicine, mainly in the Northeastern Brazil. The leaf extracts of Turnera subulata and Anacardium occidentale, for example, are applied as an alternative in the treatment of lots diseases such diabetes, hypertension, chronic pain, cancer and inflammation. Despite their wide use, the effects of these are still not well described. Thus, we to evaluate the antioxidant and anti-inflammatory properties of leaf extracts of T. subulata and A. occidentale in an in vitro inflammation model of using lipopolysaccharide macrophage RAW 264.7 cells. Therefore, we quantified the inflammatory response markers in the lineage, as well as its ability to modulate the MAPKs (p38, ERK½ and JNK). In addition, MTT and SRB viability tests, TNF-α and IL-1β modulation evaluation were performed, as well as specific tests for antioxidant evaluation such as DCFH, TBARS, thiol proteins and carbonylation of proteins. The extracts presented antioxidant and anti-inflammatory activities, and it was possible to observe that co-treatment with the extract of leaf the T. subulata was able to reduce the oxidative stress in the cells, produced by the inflammatory response, the capacity for modulate directly the inflammatory response, altering the activity of MAPK pathway members. In the extract of leaf the A. occidentale the results also showed antioxidant activity, which was observed when the extract decreased the oxidative damage in cells of macrophages treated with the dosages of 0.5 and 5 μg/mL. In addition, this extract reversed the oxidative damage and inflammatory parameters induced by lipopolysaccharide in the cells tested, being able to inhibit the release of TNF-α and IL-1β. Inflammatory markers such as TLR4, RAGE and CD40 that are induced by LPS were also modulated. Later, we evaluated the signaling pathways involved in the lipopolysaccharide-mediated inflammatory response. The extract of A. occidentale blocked the effects of lipopolysaccharide on the phosphorylation of ERK½, SAPK/ JNK and p38. In this way, our results indicate the possible antioxidant and anti-inflammatory effects of the aqueous extracts of T. subulata and A. occidentale and demonstrate the possible biological mechanisms responsible for these effects.