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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, OBJECTIVE, METHODS, RESULTS. Meshes: Administration, Inhalation, Animals, Blotting, Western, Carbon Monoxide, Disease Models, Animal, Female, Heme Oxygenase-1, Male, Mice, Mice, Inbred C57BL, Mitochondria, NF-E2-Related Factor 2, Organelle Biogenesis, Peritonitis, Random Allocation, Real-Time Polymerase Chain Reaction, Risk Assessment, Sepsis, Staphylococcal Infections, Staphylococcus aureus, Survival Rate, Up-Regulation.
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Does activation of mitochondrial biogenesis by heme oxygenase-1-mediated NF-E2-related factor-2 induction rescue mice from lethal Staphylococcus aureus sepsis? Context: Mitochondrial damage is an important component of multiple organ failure syndrome, a highly lethal complication of severe sepsis that lacks specific therapy. Mitochondrial quality control is regulated in part by the heme oxygenase-1 (HO-1; Hmox1) system through the redox-regulated NF-E2-related factor-2 (Nrf2) transcription factor, but its role in mitochondrial biogenesis in Staphylococcus aureus sepsis is unknown. To test the hypothesis that Nrf2-dependent up-regulation of the HO-1/carbon monoxide (CO) system would preserve mitochondrial biogenesis and rescue mice from lethal S. aureus sepsis. A controlled murine S. aureus peritonitis model with and without inhaled CO was examined for HO-1 and Nrf2 regulation of mitochondrial biogenesis and the resolution of hepatic mitochondrial damage. Sepsis survival was significantly enhanced using inhaled CO (250 ppm once-daily for 1 h), and linked mechanistically to Hmox1 induction and mitochondrial HO activity through Nrf2 transcriptional and Akt kinase activity. HO-1/CO stimulated Nrf2-dependent gene expression and nuclear accumulation of nuclear respiratory factor-1, -2α (Gabpa), and peroxisome proliferator-activated receptor gamma coactivator-1α; increased mitochondrial transcription factor-A and citrate synthase protein levels; and augmented mtDNA copy number. CO enhanced antiinflammatory IL-10 and reduced proinflammatory tumor necrosis factor-α production. By contrast, Nrf2(-/-) and Akt1(-/-) mice lacked CO induction of Hmox1 and mitochondrial biogenesis, and CO rescued neither strain from S. aureus sepsis.
assistant
We identify an inducible Nrf2/HO-1 regulatory cycle for mitochondrial biogenesis that is prosurvival and counter-inflammatory in sepsis, and describe targeted induction of mitochondrial biogenesis as a potential multiple organ failure therapy. Final Decision: yes