Effects of adiponectin on acute lung injury in cecal ligation and puncture–induced sepsis rats

Abstract

BackgroundThe purpose of this study was to elucidate the possible beneficial effects of adiponectin (APN) on acute lung injury in a rat model of sepsis. MethodsWe subjected male Sprague-Dawley rats to cecal ligation and puncture (CLP) to establish sepsis models. We randomly animals divided into four groups: control (C), model (CLP), preemptive APN administration (APN plus CLP), and delayed APN administration (CLP plus APN). We killed the animals 24 h after CLP and collected blood samples to determine PaO2 and PaCO2. Lung samples were taken for histologic assessment and measurement of myeloperoxidase activity. We measured neutrophil and macrophage count and cytokine production (tumor necrosis factor-α and macrophage inflammatory protein-2) in bronchoalveolar lavage fluid. ResultsHistology findings and lung injury score analysis revealed acute lung injury in rats in the CLP group, whereas those in the APN-treated group had mild lung injury. The effects of sepsis on the increasing cell number in bronchoalveolar lavage fluid as well as the wet/dry weight ratio, neutrophil infiltration, and myeloperoxidase activity of lung tissue were significantly attenuated by APN administration. Adiponectin also significantly alleviated hypoxemia and hypercapnia resulting from the development of lung injury. In addition, in APN-treated rats, the levels of pulmonary inflammatory molecule (macrophage inflammatory protein-2) and cytokine (tumor necrosis factor-α) were down-regulated compared with the CLP group. ConclusionsAdiponectin administration ameliorates acute lung injury in a rat model of sepsis induced by CLP, no matter whether it is administrated before or after the onset of sepsis.