Expression of Matrix Metalloproteinases 2 and 9 in Mice with hyperoxia-induced Acute Lung Injury

Objective To investigate the role of matrix metalloproteinases (MMP-2, MMP-9) in the pathogenesis of acute lung injury induced by hyperoxia. Methods Seventy-two mice were exposed in sealed cages with ＞95% high concentration oxygen (for 24-72 hours) or room air. The expression and activity of MMP-2 and MMP-9 in bronchoalveolar lavage fluids (BALF) and lung tissues at 24, 48 and 72 hours of hyperoxia were studied by gelatin zymography, reverse transcript-polymerase chain reaction and immunohistochemistry. Result Acute lung injury caused by hyperoxia was accompanied with increased expression and activity of MMP-2 and MMP-9 in BALF, an upregulation of MMP-2, MMP-9 mRNA and protein in lung tissues. Conclusion MMP-2 and MMP-9 play an important role in the development of hyperoxia-induced acute lung injury in mice.