Muscle mass preservation

Muscle mass preservation is a physiological and therapeutic objective rather than a single molecular target. It represents the maintenance of skeletal muscle tissue through a balance between protein synthesis (anabolism) and protein degradation (catabolism). Key molecular pathways involved in this process include the myostatin/activin signaling axis, which acts as a negative regulator of muscle growth, and the IGF-1/Akt/mTOR pathway, which promotes protein translation and muscle hypertrophy [8, 13]. Clinically, preserving muscle mass is critical in addressing conditions such as sarcopenia, cancer-associated cachexia, and muscle loss associated with intensive weight loss therapies, including GLP-1 receptor agonists [1, 7, 14]. Therapeutic strategies currently target specific receptors and ligands, such as growth differentiation factor 8 (myostatin), the activin type IIB receptor (ACVR2B), and the androgen receptor, to prevent atrophy and improve metabolic health [6, 9, 14]. Drug candidates like bimagrumab and various selective androgen receptor modulators (SARMs) are being investigated for their ability to spare lean mass while promoting fat loss [9, 14].

Other names

Lean mass preservationMuscle maintenanceMuscle sparingSkeletal muscle preservationMaintenance of lean body mass

Preservation is achieved through the inhibition of catabolic signaling (e.g., myostatin/activin blockade via ActRII receptors), activation of anabolic steroid receptors (e.g., androgen receptor), or stimulation of the mTORC1 pathway to shift the balance toward muscle protein synthesis and away from ubiquitin-proteasome-mediated degradation.