Cutting Edge: A2B Adenosine receptor signaling provides potent protection during intestinal ischemia/reperfusion injury.

Gastrointestinal ischemia/reperfusion (IR) injury significantly contributes to the morbidity and mortality of critical illness. In this study, we hypothesized a protective role for extracellular adenosine signaling in intestinal IR injury. Initial profiling studies of mucosal scrapings following murine IR demonstrated selective induction of the A2B adenosine receptor (A2BAR) transcript. Moreover, gene-targeted mice for the A2BAR showed more profound intestinal IR injury compared with controls. In contrast, A2AAR(-/-) mice exhibited no differences in intestinal injury compared with littermate controls. In addition, selective inhibition of the A2BAR resulted in enhanced intestinal inflammation and injury during IR. Furthermore, A2BAR agonist treatment (BAY 60-6583) protected from intestinal injury, inflammation, and permeability dysfunction in wild-type mice, whereas the therapeutic effects of BAY 60-6583 were abolished following targeted A2BAR gene deletion. Taken together, these studies demonstrate the A2BAR as a novel therapeutic target for protection during gastrointestinal IR injury.