Cellular energetics and mitochondrial uncoupling in canine aging

Area of Science:

• Genomics
• Comparative Biology
• Aging Research

Background:

• Dogs exhibit significant lifespan variation, inversely correlated with body size.
• This variation offers a unique model for studying longevity-determining traits.
• Over 190 dog breeds present a diverse dataset for genetic and physiological studies.

Purpose of the Study:

• To identify novel genetic regulators associated with longevity in dogs.
• To investigate the role of mitochondrial properties in lifespan differences between dog breeds.
• To explore the link between thermoregulation, metabolism, and canine aging.

Main Methods:

• Genome-wide association study (GWAS) on 4169 canines across 110 breeds.
• Analysis of primary dermal fibroblasts from short-lived (large) and long-lived (small) breeds.
• Mitochondrial property assessment, including respiration, uncoupling, and electron transport chain function.

Main Results:

• Novel candidate regulators of longevity were identified through GWAS.
• Long-lived dog breeds possess more uncoupled mitochondria with greater respiratory capacity.
• Cells from long-lived breeds show higher catabolism and beta-oxidation rates.
• Short-lived breeds' cells accumulate metabolites for biosynthesis and growth.

Conclusions:

• Mitochondrial bioenergetics and thermoregulation are key factors in canine lifespan variation.
• The uncoupled metabolic profile in long-lived breeds may enhance thermogenesis and reduce oxidative stress.
• Cellular characteristics in long-lived breeds potentially delay age-related dysfunction and disease.