Parathyroid Hormone as a Modulator of Skeletal Muscle: Insights into Bone–Muscle and Nerve–Muscle Interactions

Parathyroid hormone (PTH) has been studied to determine its broader role in musculoskeletal health, particularly its effects on skeletal muscle. Bone and muscle are inextricably linked via mechanical loading and biochemical signaling, with both processes playing important roles in muscular metabolism and function. Furthermore, the nervous system must maintain muscle mass and function, as neuromuscular transmission controls muscle contraction, protein synthesis, and energy metabolism. As a systemic endocrine regulator, PTH influences the physiology of skeletal muscle—both directly and through interactions with bone and the nervous system, modulating myokines, osteokines, and neuromuscular activity. The intricate relationships between PTH, muscle, bone, and nerves continue to be investigated due to their implications for aging, metabolic pathologies, and musculoskeletal disorders.