Ahamed K, Epaud R, Holzenberger M, Bonora M, Flejou JF, Puard J, Clement A, Henrion-Caude A. Deficiency in type 1 insulin-like growth factor receptor in mice protects against oxygen-induced lung injury.
Respir Res 2005;
6:31. [PMID:
15819984 PMCID:
PMC1084363 DOI:
10.1186/1465-9921-6-31]
[Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2005] [Accepted: 04/08/2005] [Indexed: 11/29/2022] Open
Abstract
Background
Cellular responses to aging and oxidative stress are regulated by type 1 insulin-like growth factor receptor (IGF-1R). Oxidant injury, which is implicated in the pathophysiology of a number of respiratory diseases, acutely upregulates IGF-1R expression in the lung. This led us to suspect that reduction of IGF-1R levels in lung tissue could prevent deleterious effects of oxygen exposure.
Methods
Since IGF-1R null mutant mice die at birth from respiratory failure, we generated compound heterozygous mice harboring a hypomorphic (Igf-1rneo) and a knockout (Igf-1r-) receptor allele. These IGF-1Rneo/- mice, strongly deficient in IGF-1R, were subjected to hyperoxia and analyzed for survival time, ventilatory control, pulmonary histopathology, morphometry, lung edema and vascular permeability.
Results
Strikingly, after 72 h of exposure to 90% O2, IGF-1Rneo/- mice had a significantly better survival rate during recovery than IGF-1R+/+ mice (77% versus 53%, P < 0.05). The pulmonary injury was consistently, and significantly, milder in IGF-1Rneo/- mice which developed conspicuously less edema and vascular extravasation than controls. Also, hyperoxia-induced abnormal pattern of breathing which precipitated respiratory failure was elicited less frequently in the IGF-1Rneo/- mice.
Conclusion
Together, these data demonstrate that a decrease in IGF-1R signaling in mice protects against oxidant-induced lung injury.
Collapse