New insights into the regulation of inflammation by adenosine.
Adenosine, long known as a regulator of cardiovascular function, has recently been identified as a significant paracrine inhibitor of inflammation that acts primarily by activation of A2A adenosine receptors (A2AARs) on lymphoid or myeloid cells. In this issue of the JCI, Yang et al. describe a proinflammatory phenotype resulting from deletion of the gene encoding the A2B adenosine receptor (A2BAR) in the mouse, suggesting that activation of the A2BAR can also have antiinflammatory effects (see the related article beginning on page 1913). Nevertheless, the role of the A2BAR remains enigmatic since its activation can either stimulate or inhibit the release of proinflammatory cytokines in different cells and tissues.
Linden
Joel
J
Department of Medicine and Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia 22908, USA. jlinden@virginia.edu
D000241:Adenosine / Q000378:metabolism*; D000818:Animals; D007249:Inflammation / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D010641:Phenotype; D043704:Receptor, Adenosine A2B / Q000235:genetics / Q000378:metabolism*
D043704:Receptor, Adenosine A2B; D000241:Adenosine