Paracoccidioides brasiliensis pancreatic destruction in Calomys callosus experimentally infected.
BACKGROUND
The wild rodent Calomys callosus is notably resistant to Trypanosoma cruzi infection. In order to better characterize this animal model for experimental infections, we inoculated C. callosus intraperitoneally with Paracoccidioides brasiliensis, a thermally dimorphic fungus that causes a chronic disease with severe granuloma formation in the mouse and humans. The dissemination of P. brasiliensis cells through the lungs, liver, pancreas, and spleen was assessed by histological analysis.


RESULTS
The animals were susceptible to infection and showed a granulomatous reaction. C. callosus presented peritonitis characterized by the presence of exudates containing a large number of yeast cells. Extensive accumulation of yeast cells with intense destruction of the parenchyma was observed in the pancreas, which reduced the glucose levels of infected animals. These lesions were regressive in the liver, spleen, and lungs until complete recovery. The role of estrogen during C. callosus infection with P. brasiliensis was addressed by infecting ovariectomized animals. It was observed a reduced inflammatory response as well as reduced extension of tissue damage. Removal of ovaries reestablished the normal glucose levels during infection.


CONCLUSIONS
Taken together, the results presented here reveal the pancreas as being an important organ for the persistence of P. brasiliensis during infection of C. callosus and that estrogen plays an important role in the susceptibility of the animals to this pathogen.
Laboratório de Imunopatologia das Doenças Infecciosas, Departamento de Microbiologia, Imunologia, Parasitologia e Patologia, Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiania, Goiás, Brasil. cimfortes@hotmail.com
Rogério M
RM
Fortes
André
A
Kipnis
Ana Paula
AP
Junqueira-Kipnis
D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D004195:Disease Models, Animal; D004967:Estrogens / Q000032:analysis; D005260:Female; D007958:Leukocyte Count; D008099:Liver / Q000382:microbiology / Q000473:pathology; D008168:Lung / Q000382:microbiology / Q000473:pathology; D010052:Ovariectomy; D010179:Pancreas / Q000382:microbiology* / Q000473:pathology; D010228:Paracoccidioides / Q000472:pathogenicity*; D010229:Paracoccidioidomycosis / Q000473:pathology*; D010538:Peritonitis / Q000382:microbiology / Q000473:pathology; D016205:Sigmodontinae / Q000382:microbiology*; D013154:Spleen / Q000382:microbiology / Q000473:pathology
D001786:Blood Glucose; D004967:Estrogens