Anthelmintic activity in vitro and in vivo of Baccharis trimera (Less) DC against immature and adult worms of Schistosoma mansoni

Abstract

Although its efficiency against all Schistosoma species, praziquantel (PZQ) shows low efficacy against schistosomula and juvenile stages. The potential for development of resistance to PZQ has justified the search for new alternative chemotherapies. In this scenario, studies to new formulations, more comprehensive and without adverse effects, are being conducted. One viable and promising treatment is the study of medicinal plants as a new approach to the experimental treatment for Schistosomiasis. Amongst all the variety of the medicinal species studied, we can highlight Baccharis trimera (Less) DC, known as "Carqueja-amarga". This paper not only describes the effect of crude dichloromethane extract (DE) and aqueous fraction (AF) obtained from B. trimera, in vitro but also is the first one that investigates the in vivo efficacy of B. trimera against schistosomula, juvenile and adult worms of Schistosoma mansoni BH strain. In the experiment, mice were treated with DE, AF and PZQ (40 and 200mg/kg) over the period of larval development (3 and 30 post-infection; pi), and adult worms (60days post-infection; pi). The in vitro results show that the DE and AF effects are dose-dependents, being the 130μg/mL the most effective one in a shorter period of incubation. The exposure of the in vitro samples over adult parasites were able to inhibit 100% of the oviposition in females. Likewise caused the mortality of the parasites with morphological alterations on the tegument, on the suckers, oral and acetabulum, in both males and females after 6-72h of exposure. Additionally, the in vivo treatments against juvenile and adult infection were more effective compared to the control group untreated. Administrations of AF and DE in day 30pi (juvenile worms) show female worm total burden reductions of 75% and 68% respectively. At the same period of infection reductions of respectively 98% and 97% egg/g in the faeces were seen. In relation to the different egg developmental stages (oogram), the results showed significant reductions, due to the reduction in the number of worms, especially the females. In conclusion, B. trimera exhibits major schistosomicidal effects in vivo against immature and adult worms of S. mansoni, opening up perspectives for future researches on substance or compound isolation and the elucidation of its mechanisms of action.

Schistosomicidal activity and docking of Schistosoma mansoni ATPDase 1 with licoflavone B isolated from Glycyrrhiza inflata (Fabaceae)

“…Schistosomiasis is a neglected tropical disease, which there is no vaccine and chemotherapy relies on only PZQ (Oliveira et al 2014 In this context, G. inflata roots possess high potential for providing biologically activity compounds against parasites, such as Leishmania (Nielsen et al 1995; M A N U S C R I P T…”

“…Then, the reliance on one single drug is alarming and emphasizes the need for research and development of novel therapeutic agents against this neglected tropical disease (Oliveira et al 2014). …”

Murine cysticercosis model: Influence of the infection time and the time of treatment on the cysticidal efficacy of albendazole and praziquantel

“…Stettler et al (2004) used ABZ at 50 mg/kg against alveolar murine echinococcosis. With regard to PZQ, doses of 40 and 200 mg/kg have been evaluated for the treatment of murine schistosomiasis (de Oliveira et al, 2014). Taking into account these studies, we decided to use a dose of 50 mg/kg for both drugs.…”

Comparative Evaluation of Anthelmintic Activity of Edible and Ornamental Pomegranate Ethanolic Extracts againstSchistosoma mansoni

“…The research on medicinal plants is encouraged by the WHO, considering that certain traditional knowledge on curative plants could add up to the development of new pharmaceutical products as well as to the combat against diseases that affects the populations of developing countries [9, 10]. …”