Adora2b adenosine receptor signaling protects during acute kidney injury via inhibition of neutrophil-dependent TNF-α release

J Immunol. 2012 Nov 1;189(9):4566-73. doi: 10.4049/jimmunol.1201651. Epub 2012 Oct 1.

Abstract

Renal ischemia is among the leading causes of acute kidney injury (AKI). Previous studies have shown that extracellular adenosine is a prominent tissue-protective cue elicited during ischemia, including signaling events through the adenosine receptor 2b (Adora2b). To investigate the functional role of Adora2b signaling in cytokine-mediated inflammatory pathways, we screened wild-type and Adora2b-deficient mice undergoing renal ischemia for expression of a range of inflammatory cytokines. These studies demonstrated a selective and robust increase of TNF-α levels in Adora2b-deficient mice following renal ischemia and reperfusion. Based on these findings, we next sought to understand the contribution of TNF-α on ischemic AKI through a combination of loss- and gain-of-function studies. Loss of TNF-α, through either Ab blockade or study of Tnf-α-deficient animals, resulted in significantly attenuated tissue injury and improved kidney function following renal ischemia. Conversely, transgenic mice with overexpression of TNF-α had significantly pronounced susceptibility to AKI. Furthermore, neutrophil depletion or reconstitution of Adora2b(-/-) mice with Tnf-α-deficient neutrophils rescued their phenotype. In total, these data demonstrate a critical role of adenosine signaling in constraining neutrophil-dependent production of TNF-α and implicate therapies targeting TNF-α in the treatment of ischemic AKI.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Retracted Publication

MeSH terms

  • Acute Kidney Injury / genetics
  • Acute Kidney Injury / immunology*
  • Acute Kidney Injury / metabolism*
  • Animals
  • Disease Models, Animal
  • Genetic Predisposition to Disease
  • Ischemia / genetics
  • Ischemia / immunology
  • Ischemia / metabolism
  • Mice
  • Mice, 129 Strain
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mice, Transgenic
  • Neutrophils / immunology*
  • Neutrophils / metabolism*
  • Neutrophils / pathology
  • Receptor, Adenosine A2B / deficiency
  • Receptor, Adenosine A2B / genetics
  • Receptor, Adenosine A2B / physiology*
  • Reperfusion / methods
  • Signal Transduction / genetics
  • Signal Transduction / immunology*
  • Tumor Necrosis Factor-alpha / antagonists & inhibitors*
  • Tumor Necrosis Factor-alpha / deficiency
  • Tumor Necrosis Factor-alpha / metabolism*

Substances

  • Receptor, Adenosine A2B
  • Tumor Necrosis Factor-alpha