Fig. 8. Irisin inhibitor eliminated the protective effect of irisin on IR-injured lung.

(A) Effect of irisin and genipin administration on lung edema in IR mice. Arterial blood samples were drawn from individual mice, and plasma PaO₂ (B) and PaCO₂ (C) were measured; n = 5 for control, 4 for genipin alone, 4 for IR, 4 for (IR + irisin), and 4 for (IR + irisin + genipin) (*P < 0.05 versus control and ^#P < 0.05 versus irisin-treated lung IR mice). (D) Effect of genipin on lactate dehydrogenase (LDH) concentration in supernatant from A549 cells after AR with or without irisin administration (*P < 0.05 versus control cells and ^#P < 0.05 versus irisin-treated AR cells; n = 4). (E and F) Effect of genipin on mitochondria-mediated apoptosis in A549 cells after AR, with or without irisin administration. Cyc c release (E) was expressed as the ratio of cyc c in cytosol and mitochondria, and caspase 9 activity (F) was expressed as the ratio of active caspase 9 and GAPDH (*P < 0.05 versus control cells and ^#P < 0.05 versus irisin-treated AR cells; n = 4).