Avaliação das atividades antimalárica e antitoxoplasma dos compostos complexados obtidos da Bidens pilosa (Asteraceae)

Abstract

Parasitic diseases affecting hundreds of millions of people worldwide, killing millions of these every year. The malaria and toxoplasmosis are the major parasitic dis-eases of the world, the first is caused by Plasmodium, a parasite constantly connected to cases of resistance to conventional treatments, the second is a pro-tozoonose prevalence worldwide caused by Toxoplasma gondii, which has in its treatment of an important cause adverse effects. The nature and plants comes mainly in providing medicinal compounds for thousands of years, she being the main source of isolation of bioactive molecules of low molecular weight. The Bidens pilosa, a plant well known in ethnopharmacology due to its wide use by indigenous peoples bra-ian. Recently the Bidens pilosa had proven its antimalarial action, however, their bioactive molecules proved labile and therefore became necessary to stabilize these molecules using pharmacological excipients. Therefore, our objective is to evaluate the potential antiparasitic complexed extracts obtained from Bidens pilosa Zando-used models of malaria and toxoplasmosis, as well as the safe use of these new extracts. For this test was done cytotoxicity (MTT) with Hela cell S5 (1x104 cells / well) with crude extracts (Bp.Ra.Liof) and complexed (Bp.Ra.Bc and Bp.Ra.At) Root Bidens pilosa at concentrations ranging from 5000 to 80 mg / ml. Acute toxicity in vivo, following the protocol of OECD / OECD 2001. Testing in vivo susceptibility of the ME49 strain of Toxoplasma gondii. Extracts Bp.Ra.Liof., And Bp.Ra.Bc Bp.Ra.At were used in concentrations of 200, 300 and 400 mg / kg and control with South fadiazina 200 mg / kg, the animals showed high mortality and morbidity monitored over 30 days. The susceptibility of Plasmodium were evaluated in vitro with Plasmodium falci-parum with extracts Bp.Ra.liof (50 to 3.12 / ml), Bp.Ra.At. (75 to 4.7 g / ml) and Bp.Ra.Bc (100 to 6.25 ug / ml) and in vivo in Plasmodium berghei with extracts Bp.Ra.Bc (50, 200, 800 mg / kg ) Bp.Ra.At (37.5, 150, 600 mg / kg) and Bp.Ra.liof (25, 100, 400 mg / kg). Tests for cytotoxicity to HeLa cell S5 and acute toxicity in vivo showed that all the extracts tested (Bp.Ra.Liof, and Bp.Ra.Bc Bp.Ra.At) have low toxicity and no significant difference between them. The toxoplasma test showed that the extracts did not significantly increased survival of the animals. Tests antimalarials in vivo and in vitro extracts complexed proved more efficient that the crude mortality reduction both in the in vivo test, but also in the reduction of parasitemia in tests in vivo and in vitro.