Screening of South American anti-helmintic plant infusions on Trichinella spiralis

SARACINO, MP; AGUDELO, I; VILA, CC; LOMBARDO, T; DIAZ, M; RICCO, R; BALDI, PC

Ciudad del Cabo

Simposio; Keystone Symposium Helminths: New Insights from Immunity to Global Health; 2019

Keystone Symposia

Helminth infections are still an international concern, not only affecting people in Latin America but also throughout the world. Given the fact that they can cause chronic infections, and in some cases, even public health emergencies, we turned our attention to medicinal plants used in the South American folk medicine as antiparasitic treatment. Trichinella spiralis is a parasite nematode which infects a broad range of mammals, among them humans and pigs, causing not only epidemiological problems but also important economic losses to pork meat producers. The aim of this work was to assess the efficacy of Dysphania ambrosioides (L.) Mosyakin & Clemants (Chenopodiaceae), Tagetes minuta L. and Baccharis salicifolia (Ruiz & Pav.) Pers. (Asteraceae) infusions on the survival of T. spiralis live stages: muscle larvae (ML), adult worms (AW) and newborn larvae (NBL) in in vitro and/or in vivo assays.For in vitro assays, ML and AW were incubated for 2, 4 and 24 h while NBL were incubated for 3 and 24 h with the infusions at different dilutions. After incubation, parasite mortality percentage (%M) was evaluated. We found that D. ambrosioides and T. minuta infusions produced a high %M of ML and AW when incubated for 24 h. B. salicifolia infusion affected the survival of three parasite stages at 24 h and also that of NBL at 3 h, both in a dilution dependent manner. Given this last result, we carried out an in vivo assay in which Swiss mice were orally infected with 200 ML and were treated with one dose/day for 3 days of PBS, mebendazole or B. salicifolia infusion starting at day 3 p.i. ML were recovered by artificial digestion at day 30 p.i. in order to determine the parasite burden (ML/g). We observed that B. salicifolia infusion reduced the parasite burden by 77.5% whereas mebendazole reduced it by 95.6%, both compared to the PBS group.In conclusion, the high protection observed suggests that these infusions are active in vitro against T. spiralis and, in the case of B. salicifolia, the infusion is also effective in in vivo conditions.