The angiotensin II/AT1 receptor pathway mediates malaria-induced acute kidney injury

PLoS One. 2018 Sep 11;13(9):e0203836. doi: 10.1371/journal.pone.0203836. eCollection 2018.

Abstract

Malaria-induced acute kidney injury (MAKI) is a life-threatening complication of severe malaria. Here, we investigated the potential role of the angiotensin II (Ang II)/AT1 receptor pathway in the development of MAKI. We used C57BL/6 mice infected by Plasmodium berghei ANKA (PbA-infected mice), a well-known murine model of severe malaria. The animals were treated with 20 mg/kg/day losartan, an antagonist of AT1 receptor, or captopril, an angiotensin-converting enzyme inhibitor. We observed an increase in the levels of plasma creatinine and blood urea nitrogen associated with a significant decrease in creatinine clearance, a marker of glomerular flow rate, and glomerular hypercellularity, indicating glomerular injury. PbA-infected mice also presented proteinuria and a high level of urinary γ-glutamyltransferase activity associated with an increase in collagen deposition and interstitial space, showing tubule-interstitial injury. PbA-infected mice were also found to have increased fractional excretion of sodium (FENa+) coupled with decreased cortical (Na++K+)ATPase activity. These injuries were associated with an increase in pro-inflammatory cytokines, such as tumor necrosis factor alpha, interleukin-6, interleukin-17, and interferon gamma, in the renal cortex of PbA-infected mice. All modifications of these structural, biochemical, and functional parameters observed in PbA-infected mice were avoided with simultaneous treatment with losartan or captopril. Our data allow us to postulate that the Ang II/AT1 receptor pathway mediates an increase in renal pro-inflammatory cytokines, which in turn leads to the glomerular and tubular injuries observed in MAKI.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Kidney Injury / etiology*
  • Acute Kidney Injury / metabolism*
  • Acute Kidney Injury / pathology
  • Angiotensin II / metabolism*
  • Angiotensin II Type 1 Receptor Blockers / pharmacology
  • Angiotensin-Converting Enzyme Inhibitors / pharmacology
  • Animals
  • Captopril / pharmacology
  • Disease Models, Animal
  • Kidney / drug effects
  • Kidney / metabolism
  • Kidney / pathology
  • Losartan / pharmacology
  • Malaria / complications*
  • Malaria / metabolism*
  • Malaria / pathology
  • Male
  • Mice, Inbred C57BL
  • Plasmodium berghei
  • Random Allocation
  • Receptor, Angiotensin, Type 1 / metabolism*

Substances

  • Angiotensin II Type 1 Receptor Blockers
  • Angiotensin-Converting Enzyme Inhibitors
  • Receptor, Angiotensin, Type 1
  • Angiotensin II
  • Captopril
  • Losartan

Grants and funding

This work was supported by grants from the following Brazilian agency: Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (http://www.faperj.br/): E-26/202.950/2016 (AASP); E-26/201.197/2014 and E-26/202.833/2017 (CCN).