The Preservation of Muscle Mitochondrial Machinery During Hypometabolic Hibernation in Scandinavian Brown Bears (Ursus arctos).

ABSTRACT:

Aim

Unlike humans, brown bears (Ursus arctos) uniquely preserve skeletal muscle mass and function during months of hibernation despite prolonged fasting and inactivity. We investigated how mitochondrial energetics respond in skeletal muscle to support this remarkable resilience.

Methods

Muscle biopsies from eight wild brown bears were collected during hibernation and again in the active summer season. We assessed mitochondrial respiration using high-resolution respirometry and evaluated changes in protein expression, enzyme activity, and mitochondrial content through proteomics, Western blotting, enzymatic assays, and DNA quantification.

Results

Hibernation was associated with lower mitochondrial respiratory capacity, largely due to a reduction in mitochondrial densit

SUBMITTER: Bergouignan A 

PROVIDER: S-EPMC12926787 | biostudies-literature | 2026 Apr

REPOSITORIES: biostudies-literature