Effects of repetitive stress during the acute phase of Trypanosoma cruzi infection on chronic Chagas' disease in rats.
The effect of repetitive stress during acute infection with Trypanosoma cruzi (T. cruzi) on the chronic phase of ensuing Chagas' disease was the focus of this investigation. The aim of this study was to evaluate in Wistar rats the influence of repetitive stress during the acute phase of infection (7 days) with the Y strain of T. cruzi on the chronic phase of the infection (at 180 days). Exposure to ether vapor for 1 min twice a day was used as a stressor. Repetitive stress enhanced the number of circulating parasites and cardiac tissue disorganization, from a moderate to a severe diffuse mononuclear inflammatory process and the presence of amastigote burden in the cardiac fibers. Immunological parameters revealed that repetitive stress triggered a reduced concanavalin A induced splenocyte proliferation in vitro with major effects on the late chronic phase. Serum interleukin-12 concentration decreased in both stressed and infected rats in the early phase of infection although it was higher on 180 days post-infection. These results suggest that repetitive stress can markedly impair the host's immune system and enhance the pathological process during the chronic phase of Chagas' disease.
Laboratório de Parasitologia, Departamento de Análises Clinicas, Toxicológicas e Bromatológicas, Faculdade de Ciéncias Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil. leony@fcfrp.usp.br
Leony Cristina
LC
Caetano
Vânia
V
Brazão
Marina Del Vecchio
Mdel V
Filipin
Fabricia Helena
FH
Santello
Luana Naiara
LN
Caetano
Miriam Paula Alonso
MP
Toldo
Jerri C
JC
Caldeira
José Clóvis
JC
do Prado
D000208:Acute Disease; D000818:Animals; D049109:Cell Proliferation; D002598:Chagas Cardiomyopathy / Q000276:immunology / Q000473:pathology; D014355:Chagas Disease / Q000276:immunology* / Q000469:parasitology / Q000473:pathology; D002908:Chronic Disease; D004986:Ether / Q000009:adverse effects; D018664:Interleukin-12 / Q000097:blood; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013312:Stress, Physiological / Q000276:immunology*; D014349:Trypanosoma cruzi / Q000276:immunology
D004986:Ether; D018664:Interleukin-12