Interaction of Sepsis, Disuse, and Aging on Skeletal Muscle Function and Remodeling in Male and Female Mice - PubMed

3 hours ago

Sepsis leads to skeletal muscle weakness and atrophy, especially in older and immobilized patients.
The study used young (5 months) and older (20 months) male and female mice to examine the effects of sepsis, disuse, reloading, aging, and biological sex on muscle function.
Survival rates were higher in young septic mice (>84%) compared to older septic mice (~51%-60% males, ~57% females).
Disuse was the primary factor causing body mass loss, with older females showing the greatest decline (-19.8% in Sham, -17.4% in CLP).
Disuse reduced median fiber cross-sectional area (CSA) by ~27%-46% across different groups.
Combined sepsis and disuse increased CD68+ macrophages the most, while extracellular matrix (ECM) expansion was observed only in males.
Pax7+ satellite cells were significantly reduced in young males with sepsis and disuse and in older mice of both sexes with sepsis.
After reloading, older septic males retained force deficits, and septic females remained significantly atrophic.
The study concluded that muscle disuse amplifies sepsis-induced myopathy in an age- and sex-dependent manner, with incomplete recovery after reloading.

Hasty Briefsbeta