Hyperoxia exposure results in decreased expression of pro-resolution receptor ALX/FPR2 (1153.12)

Rationale: Endogenously produced polyunsaturated fatty acids (PUFAs) are key mediators of the anti-inflammatory response following acute injury. PUFAs such as resolvins and lipoxins have demonstrated potent pro-resolutionary effects in acute lung injury. These molecules have been shown to bind and exert their effects through G-coupled protein receptor Lipoxin A4/formyl peptide receptor 2 (ALX/FPR2). Previous reports suggest that various septic or sterile insults lead to an increase in ALX/FPR2 expression; however, the response of ALX/FRP2 to oxidative stress has not been elucidated. In this study, we investigated the role of ALX/FPR2 in a murine mouse model of hyperoxic acute lung injury (HALI). Methods: C57BL/6 mice were exposed to hyperoxic (50, 75, or 95% O2) or normoxic (≍ 21% O2) conditions for 24, 48, or 72hrs. Following atmospheric treatment, mice were euthanized; bronchoalveolar lavage (BAL) fluid and lung tissue were collected for analysis. BAL fluid was used to assess alveolar protein leak. Lung...