Reproduction Does Not Adversely Affect Liver Mitochondrial Respiratory Function but Results in Lipid Peroxidation and Increased Antioxidants in House Mice

• Published in: PloS one 2016-08, Vol.11 (8), p.e0160883-e0160883
• Main Authors: Mowry, Annelise V, Kavazis, Andreas N, Sirman, Aubrey E, Potts, Wayne K, Hood, Wendy R
• Format: Article
• Language: English
• Subjects: Adenosine diphosphate; Aging; Animals; Antioxidants; Antioxidants (Nutrients); Biology; Biology and Life Sciences; Catalase; Catalase - metabolism; Deoxyribonucleic acid; Design; DNA; Electron transport; Energy expenditure; Female; Females; Free radicals; House mouse; Impact damage; Lipid Peroxidation; Liver; Longevity; Male; Males; Medicine; Medicine and Health Sciences; Metabolism; Mice; Mitochondria; Mitochondria, Liver - metabolism; Mitochondrial DNA; Mus musculus; Mutation; Nutrition research; Oxidative Phosphorylation; Oxidative Stress; Oxygen; Oxygen consumption; Peroxidation; Physiological aspects; Physiology; Reproduction; Research and Analysis Methods; Respiration; Respiratory function; Rodents; Senescence; Sexual behavior; Studies; Superoxide Dismutase - metabolism; Tradeoffs
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0160883

Reproduction is thought to come at a cost to longevity. Based on the assumption that increased energy expenditure during reproduction is associated with increased free-radical production by mitochondria, oxidative damage has been suggested to drive this trade-off. We examined the impact of reproduction on liver mitochondrial function by utilizing post-reproductive and non-reproductive house mice (Mus musculus) living under semi-natural conditions. The age-matched post-reproductive and non-reproductive groups were compared after the reproductive females returned to a non-reproductive state, so that both groups were in the same physiological state at the time the liver was collected. Despite increased oxidative damage (p = 0.05) and elevated CuZnSOD (p = 0.002) and catalase (p = 0.04) protein levels, reproduction had no negative impacts on the respiratory function of liver mitochondria. Specifically, in a post-reproductive, maintenance state the mitochondrial coupling (i.e., respiratory control ratio) of mouse livers show no negative impacts of reproduction. In fact, there was a trend (p = 0.059) to suggest increased maximal oxygen consumption by liver mitochondria during the ADP stimulated state (i.e., state 3) in post-reproduction. These findings suggest that oxidative damage may not impair mitochondrial respiratory function and question the role of mitochondria in the trade-off between reproduction and longevity. In addition, the findings highlight the importance of quantifying the respiratory function of mitochondria in addition to measuring oxidative damage.