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We investigated sex-specific responses to hyperoxia-induced acute lung injury (HALI) in rats. Female rats exhibited attenuated severity, with less pleural effusion, pulmonary edema, and apoptosis than males. Studies in isolated mitochondria, lung tissue homogenates, and isolated lungs indicate that this attenuated severity is associated with mitochondrial adaptations and enhanced tissue H2O2scavenging capacity. These findings underscore the importance of sex as a biological variable and identify mitochondrial complex II as a potential HALI therapeutic target.
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This content will become publicly available on December 1, 2026
Sex dimorphism and substrate dependency of liver mitochondrial bioenergetics and H 2 O 2 production
We examined sex-specific and substrate-dependent differences in liver mitochondrial function of adult SD rats. Liver mitochondria preferentially use GM over PM for respiration, whereas PM produces more H2O2. Female mitochondria exhibited higher respiration and H2O2production than males across all substrates, likely driven by hormonal factors and sex-specific regulatory pathways. These findings highlight the importance of both substrate and sex in shaping liver mitochondrial bioenergetics and redox function, offering insight into intrinsic metabolic differences.
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- Award ID(s):
- 2153387
- PAR ID:
- 10711372
- Publisher / Repository:
- American Physiological Society
- Date Published:
- Journal Name:
- American Journal of Physiology-Gastrointestinal and Liver Physiology
- Volume:
- 329
- Issue:
- 6
- ISSN:
- 0193-1857
- Page Range / eLocation ID:
- G664 to G679
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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