title: Physalin B inhibits Trypanosoma cruzi infection in the gut of Rhodnius prolixus by affecting the immune system and microbiota.
abstract: Physalin B is a natural secosteroidal, extracted from the Solanaceae plant, Physalis angulata, and it presents immune-modulator effects on the bloodsucking bug, Rhodnius prolixus. In this work, R. prolixus was treated with physalin B at a concentration of 1 mg/ml of blood meal (oral application), or 20 ng/insect (applied topically) or 57 ng/cm(2) of filter paper (contact treatment), and infected with Trypanosoma cruzi Dm28c clone (2×10(6) epimastigotes/insect). The three types of applications significantly decreased the number of T. cruzi Dm28c in the gut comparing with the non-treated infected insects (controls). All groups of infected insects treated with physalin B had higher numbers of bacterial microbiota in the gut than the non-treated controls infected with T. cruzi. We observed that the infected physalin B insects with topical and contact treatments had a lower antibacterial activity in the gut when compared with control infected insects. Furthermore, infected insects with the physalin B oral treatment produced higher levels of nitrite and nitrate in the gut than control infected insects. These results demonstrate that physalin B decreases the T. cruzi transmission by inhibiting the parasite development in the insect vector R. prolixus. Herein the importance of physalin B modulation on the immune system and microbiota population in terms of parasite development and transmission are discussed.
authors.affiliation: Laboratório de Bioquímica e Fisiologia de Insetos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Rio de Janeiro, Brazil. danicastro@ioc.fiocruz.br
authors.forename: Daniele P
authors.initials: DP
authors.lastname: Castro
authors.forename: Caroline S
authors.initials: CS
authors.lastname: Moraes
authors.forename: Marcelo S
authors.initials: MS
authors.lastname: Gonzalez
authors.forename: Ivone M
authors.initials: IM
authors.lastname: Ribeiro
authors.forename: Therezinha C B
authors.initials: TC
authors.lastname: Tomassini
authors.forename: Patrícia
authors.initials: P
authors.lastname: Azambuja
authors.forename: Eloi S
authors.initials: ES
authors.lastname: Garcia
mesh_terms: D000818:Animals; D006790:Host-Parasite Interactions / Q000187:drug effects*; D054892:Metagenome / Q000187:drug effects; D018978:Molting / Q000187:drug effects; D009566:Nitrates / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism; D026361:Reactive Nitrogen Species / Q000378:metabolism; D012239:Rhodnius / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism / Q000382:microbiology / Q000469:parasitology; D012632:Secosteroids / Q000494:pharmacology*; D014349:Trypanosoma cruzi / Q000187:drug effects*
chemical_list: D009566:Nitrates; D009573:Nitrites; D026361:Reactive Nitrogen Species; D012632:Secosteroids; C033270:physalin B