Mitochondrial DNA damage-associated molecular patterns mediate a feed-forward cycle of bacteria-induced vascular injury in perfused rat lungs.

Autor:	Kuck JL; Department of Pharmacology, University of South Alabama, College of Medicine, Mobile, Alabama;, Obiako BO; Department of Pharmacology, University of South Alabama, College of Medicine, Mobile, Alabama;, Gorodnya OM; Department of Pharmacology, University of South Alabama, College of Medicine, Mobile, Alabama;, Pastukh VM; Department of Pharmacology, University of South Alabama, College of Medicine, Mobile, Alabama;, Kua J; Department of Pharmacology, University of South Alabama, College of Medicine, Mobile, Alabama;, Simmons JD; Department of Surgery and Center for Lung Biology, University of South Alabama, College of Medicine, Mobile, Alabama., Gillespie MN; Department of Pharmacology, University of South Alabama, College of Medicine, Mobile, Alabama; mgillesp@southalabama.edu.
Jazyk:	angličtina
Zdroj:	American journal of physiology. Lung cellular and molecular physiology [Am J Physiol Lung Cell Mol Physiol] 2015 May 15; Vol. 308 (10), pp. L1078-85. Date of Electronic Publication: 2015 Mar 20.
DOI:	10.1152/ajplung.00015.2015
Abstrakt:	Fragments of the mitochondrial genome released into the systemic circulation after mechanical trauma, termed mitochondrial DNA damage-associated molecular patterns (mtDNA DAMPs), are thought to mediate the systemic inflammatory response syndrome. The close association between circulating mtDNA DAMP levels and outcome in sepsis suggests that bacteria also might be a stimulus for mtDNA DAMP release. To test this hypothesis, we measured mtDNA DAMP abundance in medium perfusing isolated rat lungs challenged with an intratracheal instillation of 5 × 10(7) colony-forming units of Pseudomonas aeruginosa (strain 103; PA103). Intratracheal PA103 caused rapid accumulation of selected 200-bp sequences of the mitochondrial genome in rat lung perfusate accompanied by marked increases in both lung tissue oxidative mtDNA damage and in the vascular filtration coefficient (Kf). Increases in lung tissue mtDNA damage, perfusate mtDNA DAMP abundance, and Kf were blocked by addition to the perfusion medium of a fusion protein targeting the DNA repair enzyme Ogg1 to mitochondria. Intra-arterial injection of mtDNA DAMPs prepared from rat liver mimicked the effect of PA103 on both Kf and lung mtDNA integrity. Effects of mtDNA and PA103 on Kf were also attenuated by an oligodeoxynucleotide inhibitor of Toll-like receptor 9 (TLR-9) by mitochondria-targeted Ogg1 and by addition of DNase1 to the perfusion medium. Collectively, these findings are consistent with a model wherein PA103 causes oxidative mtDNA damage leading to a feed-forward cycle of mtDNA DAMP formation and TLR-9-dependent mtDNA damage that culminates in acute lung injury. (Copyright © 2015 the American Physiological Society.)
Databáze:	MEDLINE
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