Influence of parasite load on renal function in mice acutely infected with Trypanosoma cruzi.
BACKGROUND
Chagas disease is a neglected tropical disease caused by Trypanosoma cruzi. Despite the vast number of studies evaluating the pathophysiological mechanisms of the disease, the influence of parasite burden on kidney lesions remains unclear. Thus, the main goal of this work was to evaluate the effect of T. cruzi infection on renal function and determine whether there was a correlation between parasite load and renal injury using an acute experimental model of the disease.


RESULTS
Low, medium and high parasite loads were generated by infecting C57BL/6 mice with 300 (low), 3,000 (medium) or 30,000 (high) numbers of "Y" strain trypomastigotes. We found that mice infected with T. cruzi trypomastigotes show increased renal injury. The infection resulted in reduced urinary excretion and creatinine clearance. We also observed a marked elevation in the ratio of urine volume to kidney and body weight, blood urea nitrogen, chloride ion, nitric oxide, pro- and anti-inflammatory cytokines and the number of leukocytes in the blood and/or renal tissues of infected mice. Additionally, we observed the presence of the parasite in the cortical/medullary and peri-renal region, an increase of inflammatory infiltrate and of vascular permeability of the kidney. Overall, most renal changes occurred mainly in animals infected with high parasitic loads.


CONCLUSIONS
These data demonstrate that T. cruzi impairs kidney function, and this impairment is more evident in mice infected with high parasitic loads. Moreover, these data suggest that, in addition to the extensively studied cardiovascular effects, renal injury should be regarded as an important indicator for better understanding the pan-infectivity of the parasite and consequently for understanding the disease in experimental models.
Postgraduate Course of Pathology, Federal University of Triângulo Mineiro, Uberaba, Minas Gerais, Brazil.
Juliana Regina Dias
JR
Lemos
Wellington Francisco
WF
Rodrigues
Camila Botelho
CB
Miguel
Ricardo Cambraia
RC
Parreira
Renata Botelho
RB
Miguel
Alexandre
A
de Paula Rogerio
Carlo Jose Freire
CJ
Oliveira
Javier Emilio Lazo
JE
Chica
D000818:Animals; D002199:Capillary Permeability; D014355:Chagas Disease / Q000401:mortality / Q000469:parasitology* / Q000503:physiopathology*; D016207:Cytokines / Q000096:biosynthesis; D004195:Disease Models, Animal; D007668:Kidney / Q000378:metabolism / Q000469:parasitology* / Q000473:pathology / Q000503:physiopathology*; D007677:Kidney Function Tests; D008297:Male; D051379:Mice; D009569:Nitric Oxide / Q000096:biosynthesis; D009929:Organ Size; D059208:Parasite Load; D018512:Parasitemia / Q000469:parasitology; D014349:Trypanosoma cruzi
D016207:Cytokines; D009569:Nitric Oxide