title: Alterations triggered by steroid gonadal hormones in triglycerides and the cellular immune response of Calomys callosus infected with the Y strain of Trypanosoma cruzi.
abstract: Calomys callosus is a wild rodent found naturally infected with different Trypanosoma cruzi strains. In the work described here, groups of male and female C. callosus were subjected to orchiectomy, ovariectomy and sham operation. One month after surgery, animals were inoculated intraperitoneally (i.p.) with 4x10(4) blood trypomastigotes of the "Y" strain of T. cruzi. Parasitemia, triglycerides, nitric oxide (NO) and concanavalin A (ConA)-induced proliferation were evaluated. Parasitemia during the course of infection was significantly higher in infected and sham operated animals as compared to infected orchiectomized animals. The opposite was observed in the ovariectomized and infected group. Orchiectomized and infected animals displayed elevated triglyceride levels, as well as a more vigorous immune response, with higher splenocyte proliferation and elevated concentrations of NO. Ovariectomy resulted in an impaired immune response, as observed by a reduction of splenocyte proliferation and NO concentration. The results suggest a pivotal role for gonadal hormones in the modulation of triglyceride levels and the magnitude of the immune response during the acute phase of T. cruzi infection.
authors.affiliation: Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto FCFRP-USP, Universidade de São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Renata
authors.initials: R
authors.lastname: D'Ambrósio Fernandes
authors.forename: Leony Cristina
authors.initials: LC
authors.lastname: Caetano
authors.forename: Carla Domingues
authors.initials: CD
authors.lastname: dos Santos
authors.forename: Ana Amélia Carraro
authors.initials: AA
authors.lastname: Abrahão
authors.forename: Ana Cláudia Henriques
authors.initials: AC
authors.lastname: Pinto
authors.forename: José C
authors.initials: JC
authors.lastname: Prado
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D014355:Chagas Disease / Q000276:immunology* / Q000469:parasitology*; D004195:Disease Models, Animal; D004198:Disease Susceptibility; D005260:Female; D006790:Host-Parasite Interactions / Q000276:immunology; D007111:Immunity, Cellular; D007274:Injections, Intraperitoneal; D008213:Lymphocyte Activation; D008297:Male; D009569:Nitric Oxide; D009919:Orchiectomy / Q000009:adverse effects / Q000662:veterinary; D010052:Ovariectomy / Q000009:adverse effects / Q000662:veterinary; D018512:Parasitemia / Q000453:epidemiology; D012737:Sex Factors; D016205:Sigmodontinae / Q000097:blood / Q000276:immunology / Q000469:parasitology / Q000601:surgery; D014280:Triglycerides / Q000097:blood*; D014349:Trypanosoma cruzi / Q000254:growth & development / Q000472:pathogenicity*
chemical_list: D014280:Triglycerides; D009569:Nitric Oxide