Dados do Trabalho

Título

Rhizophora mangle (L. 1753): Phytochemical analysis, cytotoxicity and in vitro schistosomicidal evaluation against couples of Schistosoma mansoni

Objetivo (s)

We aimed at the phytochemical characterization of the Rhizophora methanolic extract, its cytotoxicity on RAW 264.7 and in vitro schistosomicidal effect against Schistosoma mansoni couples.

Material e Métodos

The methanolic extract of R. mangle leaves was analyzed by high performance liquid chromatography (HPLC). Mice infected with S. mansoni cercariae had the hepatic portal system and mesenteric vessels perfused on the 60th day of infection for couple recovery. The couples were incubated in culture plates (2 couples/well in quadruplicate) and exposed to 12.5 - 400μg/mL of the extract. Couples were monitored every 24h for 5 consecutive days to evaluate mortality, motility, unmating and oviposition, in addition to cell viability by MTT. Negative and positive controls were formed by couples incubated only in RPMI medium or 10μM PZQ, respectively.

Resultados e Conclusão

HPLC identified the flavanoid rutin as the main metabolite. Negative control exhibited typical motility and peristalsis, in addition to maintenance of mating. PZQ caused 100% mortality after 24h and mortality occurred with worms still paired (couples). The extract caused mortality and altered motility in a time and dose-dependent manner, in addition to causing pair separation at all concentrations. In 24h, 400μg/mL caused 81.25% reduction in body motility and internal organs, in addition to ventral suckers not adhered to culture plate and 100% of the couples were already unmated. At this concentration, after 72 and 120h the mortality was 56.25% and 75%, respectively. The extract at 200 and 100μg/mL after 72h caused a 100% reduction in motility and after 120h mortality of 62.5 and 56.25%, respectively. After 120h, all couples were unmated at 25 and 50μg/mL with a significant reduction in motility. No eggs were observed on any extract concentration at the different observation intervals, contrary to the negative control group, where there was oviposition and egg accumulation at all intervals. The extract reduced cell viability of the worms by 26.1, 31.74, 34.55 and 46.45% at concentrations of 50, 100, 200 and 400μg/ml, with a significant difference with PZQ. The concentrations used in the schistosomicidal evaluation study, R. mangle did not show cytotoxicity in RAW cells. R. mangle showed promising in vitro activity against S. mansoni couples, especially in worm couples separation, reducing worm cell viability and inhibiting oviposition, in addition to not exhibiting cytotoxicity.

Palavras-chave

Mangrove; Extract; Methanolic; Schistosomicidal.

Agradecimentos

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