Experimental centrocestiasis: Worm burden, morphology and fecundity of Centrocestus formosanus (Trematoda: Heterophyidae) in dexamethasone immunosuppressed mice.
Centrocestus formosanus is an intestinal foodborne trematode with medical and veterinary importance that remains with the pathological and immunological aspects of the infection in definitive host poorly studied. In the present study, we evaluated the effects of pharmacological immunosuppression by glucocorticoids in experimental centrocestiasis. Mice of the AKR/J strain were orally inoculated with 100 metacercariae of C. formosanus obtained in naturally infected fish (Australoheros facetus) collected in an urban reservoir from Brazil. Treatment with dexamethasone (25 mg/kg, via subcutaneous injection) was started 1h before infection of mice and then continued daily during 14 days post-infection. Untreated mice also infected with C. formosanus were used as control. At the end of the treatment course, all rodents were euthanized and adult parasites recovered from host intestines were subjected to morphological and morphometric analysis under optical microscopy. The worm burden in dexamethasone treated group [70±14 (41-85)] was significantly greater (p<0.0001) than that in the control group [15±4 (10-22)]. In addition, the parasites recovered from immunosuppressed mice were larger, with more developed reproductive structures and greater number of intrauterine eggs than in control mice. These parasite developmental changes induced by dexamethasone treatment are reported for the first time in experimental centrocestiasis. Moreover the higher parasite fecundity induced by glucocorticoid treatment had so far not been reported for any heterophyid species, which can have implications for the pathology and morbidity in infections caused by these parasites.
Laboratório de Taxonomia e Biologia de Invertebrados, Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. Electronic address: hudsonalves13@ig.com.br.
Hudson Alves
HA
Pinto
Laboratório de Taxonomia e Biologia de Invertebrados, Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
Vitor Luís Tenório
VL
Mati
Laboratório de Taxonomia e Biologia de Invertebrados, Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
Alan Lane
AL
de Melo
D000818:Animals; D023681:Cichlids / Q000469:parasitology*; D003907:Dexamethasone / Q000009:adverse effects; D004195:Disease Models, Animal; D005298:Fertility; D005393:Fish Diseases / Q000469:parasitology*; D006578:Heterophyidae / Q000502:physiology* / Q000648:ultrastructure; D007165:Immunosuppression Therapy / Q000662:veterinary; D008297:Male; D058488:Metacercariae; D051379:Mice; D008806:Mice, Inbred AKR; D014201:Trematode Infections / Q000469:parasitology / Q000662:veterinary*
D003907:Dexamethasone
Centrocestus formosanus; Dexamethasone; Fecundity; Immunosuppression; Morphometry