ATIVIDADE ANTI-Leishmania DA FORMULAÇÃO DO EXTRATO HIDROETANÓLICO DE Dysphania ambrosioides (L.) INCORPORADO EM MEMBRANAS DE QUITOSANA

Abstract

Leishmaniasis is a group of parasitic infectious diseases caused by protozoa of the Leishmania genus, prevalent in tropical and subtropical countries, with Cutaneous Leishmaniasis (TL) being the most common clinical form. The main therapy for TL is the prescription of pentavalent antimonials, but these are associated with significant problems such as high toxicity, drug resistance, and relapse. However, some studies indicate that the combination of natural products with leishmanicidal action with controlled drug delivery systems (CDDS) is a promising therapy for TL. This study evaluated the therapeutic potential of the hydroethanolic extract of Dysphania ambrosioides (HEDA) incorporated into a chitosan membrane as an alternative for the treatment of TL, analyzing its chemical and physicochemical profile, as well as its biological effects on leishmanicidal activity and in vitro viability of mammalian cells.EHDA was obtained from the leaves of D. ambrosioides, which were dried, ground, percolated, rotary evaporated, and lyophilized. EHDA was incorporated into 1% acetic acid and 1% chitosan and dried in an oven. The chemical characterization of polyphenols in EHDA and the membranes was determined by HPLC and total polyphenol content (TPC) and total flavonoid content (TFC). Physicochemical characterization was analyzed by Fourier Transform Infrared Spectroscopy (FTIR), Xray Diffraction (XRD), Solubility Test, UV-Visible Region Spectroscopy, Water Vapor Transmission Rate (WVTR), and Scanning Electron Microscopy (SEM).For in vitro biological assays, antipromastigote (48h) and anti-amastigote (24h) activity and cytotoxicity in macrophages (24h) were determined by the MTT method. Hemolytic activity (1h) was determined by spectrophotometer. The infection rate of macrophages by L. amazonensis (10 Leishmania/1 macrophage) was determined by counting internalized amastigotes. Quantification of reactive oxygen species production by HEDA and membranes was performed by assaying NADPH oxidase activity in macrophages using Amplex red. Caffeic acid, gallic acid, myricetin, rutin, quercitin, and kaempferol were identified as the major compounds of HEDA. TFC release kinetics demonstrated that the flavonoids were released from the membrane within 96h. Chitosan-incorporated HEDA exhibited leishmanicidal activity against promastigotes and amastigotes of Leishmania amazonensis and reduced the infection rate in a dose-dependent manner, without showing cytotoxicity to erythrocytes and macrophages. It is suggested that the observed biological effects are associated with the presence of polyphenols and flavonoids quantified after HEDA release kinetics from the membrane. Physicochemical analyses of the membranes demonstrated smooth surfaces, free of cracks and layered structures, good chemical stability at different pHs, high UV protection, and high water vapor transmission capacity, demonstrating potential use in the treatment of leishmanial ulcerative lesions. Therefore, the chitosan-incorporated HEDA membrane exhibits leishmanial activity, low cellular toxicity, and satisfactory structure and physicochemical properties.