Trypanosoma cruzi: effects of adrenalectomy during the acute phase of experimental infection.
Glucocorticoid hormones have been implicated as an important modulator of Trypanosoma cruzi pathogenesis. Since adrenal steroid hormones play a fundamental role in modulating the immune response, we hypothesized that adrenalectomy affect the course of the experimental T. cruzi infection. This study was undertaken to determine the effects of adrenalectomy during the acute phase of T. cruzi infection. Blood and tissue parasitism, macrophages, nitric oxide (NO) production and IFN-gamma were evaluated in male Wistar rats infected with the Y strain of T. cruzi. Our results show that adrenalectomized rats displayed increased number of blood and heart parasites accompanied by decreases in the total number of peritoneal macrophages and IFN-gamma when compared to controls. Adrenalectomy also reduced the levels of NO released from peritoneal macrophages of infected animals. These results suggest that adrenal corticosteroid insufficiency due to adrenalectomy could be considered an important factor during development of acute phases of experimental Chagas' disease, enhancing pathogenesis through disturbance of the host's immune system.
Guerra-Lopes
Elaine S
ES
Departamento de Parasitologia, Instituto de Biologia, Universidade Estadual de Campinas, Cidade Universitária Zeferino Vaz, CEP 13083-970 Campinas, São Paulo, Brazil.
Caldeira
Jerri C
JC
Santos
Carla D
CD
Toldo
Míriam P A
MP
Faccioli
Lúcia H
LH
Sá-Nunes
Anderson
A
Albuquerque
Sérgio
S
Prado
José C
JC
D000208:Acute Disease; D000305:Adrenal Cortex Hormones / Q000502:physiology; D000311:Adrenal Glands / Q000502:physiology*; D000315:Adrenalectomy; D000818:Animals; D002452:Cell Count; D014355:Chagas Disease / Q000276:immunology* / Q000469:parasitology / Q000473:pathology; D006321:Heart / Q000469:parasitology; D007371:Interferon-gamma / Q000096:biosynthesis / Q000097:blood; D017737:Macrophages, Peritoneal / Q000276:immunology / Q000378:metabolism*; D008297:Male; D051379:Mice; D009206:Myocardium / Q000473:pathology; D009569:Nitric Oxide / Q000096:biosynthesis; D018512:Parasitemia / Q000276:immunology / Q000469:parasitology; D051381:Rats; D017208:Rats, Wistar
D000305:Adrenal Cortex Hormones; D009569:Nitric Oxide; D007371:Interferon-gamma