Estudo fitoquímico e avaliação da atividade esquistossomicida in vitro dos extratos e metabólitos de Solidago microglossa MEYEN (Asteraceae) e Aristolochia cymbifera MART & ZUCC (Aristolochiaceae)

Abstract

Schistosomiasis affects about 207 million people in the world and, in Brazil, it is estimated that the number of infected people is 4-6 million people with Minas Gerais being one of the states that have the highest number of cases of schistosomiasis. The treatment of the disease is based on a single drug: Praziquantel (PZQ), however, there are already reports of resistance trait. In this context, extracts and secondary plant metabolites have been tested against the Schistosoma mansoni. The present work describes the phytochemical study of crude extracts from the roots of Solidago microglossa (Sm-R) and Aristolochia cymbifera (Ac) and its metabolites isolated. From the chromatographic fractionation of Sm-R, were isolated and identified three metabolites: spinasterol, α-amyrin and bauerenol, the latter two being reported for the first time in the roots of species. Since the chromatographic fractionation Ac culminated in the isolation and identification of populifolic acid and cubebin, both already isolated in species. In the in vitro schistosomicidal study, was used adult worms of S. mansoni and the parameters evaluated were alterations tegumental surface, oviposition, motility and mortality. Previous to the assay, cytotoxicity of the extracts was evaluated in Vero cells and there was no reduction in cell viability. The results showed that the concentration of 200 ug / ml Sm-R was able to decrease motor activity, alterations tegumental surface and death of all the adult worms of S. mansoni after 72 h of incubation, as well as significant reduction in oviposition. Already Ac extract, this was capable of causing reduction of motor activity, alterations tegumental surface and death of adult worms after 24 h of incubation at a concentration of 50 mg / mL, and promote reduction of oviposition. Among the isolated compounds, the mixture of bauerenol and α- amyrin, spinasterol, populifolic acid and cubebin showed weak activity and only the Sm-R 5 IV promoted reduction of motor activity and death of the parasites in 100 ug / mL after 48 h of incubation. Thus, the continuity of the study is necessary in order to identify the substances responsible for the activity of the extracts Sm-R and Ac