Laminin-111 Improves the Anabolic Response to Mechanical Load in Aged Skeletal Muscle

Abstract

Anabolic resistance to a mechanical stimulus may contribute to the loss of skeletal muscle mass observed with age. In this study, young and aged mice were injected with saline or human LM-111 (1 mg/kg). One week later, the myotendinous junction of the gastrocnemius muscle was removed via myotenectomy (MTE), thus placing a chronic mechanical stimulus on the remaining plantaris muscle for 2 weeks. LM-111 increased α7B integrin protein expression and clustering of the α7B integrin near DAPI+ nuclei in aged muscle in response to MTE. LM-111 reduced CD11b+ immune cells, enhanced repair, and improved the growth response to loading in aged plantaris muscle. These results suggest that LM-111 may represent a novel therapeutic approach to prevent and/or treat sarcopenia.

Advanced Glycation End Products Are Retained in Decellularized Muscle Matrix Derived from Aged Skeletal Muscle

“…Muscle's β1-integrin counterpart, α7, has less known effects during aging. Recent evidence suggests no differences between levels of α7B in 3and 22-month murine muscle [84]. In contrast, our data show an increase in total α7 at 20 months, suggesting a compensatory mechanism to protect muscle from sarcolemmal damage.…”