Skeletal Muscle

Original Editor - Lucinda hampton

Top Contributors - Lucinda hampton  

Introduction[edit | edit source]

Fascia surrounding muscle fibre

Skeletal muscle attaches to the bone by tendons, and together they produce our bodies movements. But it has important roles in health beyond voluntary movement. Human skeletal muscle is a very responsive tissue. Humans skeletal muscle makes up roughly 40% of total body weight and a huge 50-75% of all the bodies proteins. Muscle mass muscle mass depends on the dynamic process of protein synthesis and loss, and as such is responsive to factors including nutritional status, hormonal balance, physical activity/exercise, and injury or disease.[1][2]

Skeletal muscle fibers are crossed with a orderly pattern of fine red and white lines, hence its name striated muscle. For more on anatomical structure see Muscle Cells (Myocyte)

Biomechanical Organ[edit | edit source]

Muscle plays a large part in protein metabolism by acting as the primary reservoir for amino acids to keep protein synthesis occurring in vital tissues and organs when amino acid absorption is not inadequate from gut absoption and by providing gluconeogenic precursors. Changed muscle metabolism plays a part in the evolution of many common pathologic conditions and chronic diseases.[3]

Immune Function[edit | edit source]

Research shows the importance of regular exercise and physical activity as they boost the body’s ability to fight infections, and as a "medicine" to fight established diseases. This interaction is credited to glutamine, a non-essential amino acid that active skeletal muscle produce. It is then used by rapidly dividing cells, including lymphocytes and monocytes/macrophages, as their main source of energy.[4]

Endocrine Organ[edit | edit source]

Skeletal muscle may be viewed as an endocrine organ. Skeletal muscle releases myokines (a cytokine produced by muscles), which have are able to regulate some physiological processes.

Skeletal muscle also has a function in maintaining body homeostasis, being responsible for greater than 3/4's of all insulin-mediated glucose use. These altered myokines contribute to the pathogenesis of obesity, type 2 diabetes, and other metabolic diseases.[5]

Abnormalities[edit | edit source]

Many medical conditions occur due to abnormalities in skeletal muscles' function.

References[edit | edit source]

  1. 1.0 1.1 Frontera WR, Ochala J. Skeletal muscle: a brief review of structure and function. Calcified tissue international. 2015 Mar;96:183-95.Available:https://pubmed.ncbi.nlm.nih.gov/25294644/ (accessed 16.4.2023)
  2. Graham ZA, Lavin KM, O’Bryan SM, Thalacker-Mercer AE, Buford TW, Ford KM, Broderick TJ, Bamman MM. Mechanisms of exercise as a preventative measure to muscle wasting. American Journal of Physiology-Cell Physiology. 2021 Jul 1;321(7):C40-57.Available:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8424676/ (accessed 16.4.2023)
  3. Wolfe RR. The underappreciated role of muscle in health and disease. Am J Clin Nutr. 2006 Sep;84(3):475-82. doi: 10.1093/ajcn/84.3.475. PMID: 16960159.(Accessed 18.4.2023)
  4. Rogeri PS, Gasparini SO, Martins GL, Costa LK, Araujo CC, Lugaresi R, Kopfler M, Lancha Jr AH. Crosstalk between skeletal muscle and immune system: which roles do IL-6 and glutamine play?. Frontiers in Physiology. 2020 Oct 16;11:582258.Available:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7596683/ (accessed 17.3.2023)
  5. Feraco A, Gorini S, Armani A, Camajani E, Rizzo M, Caprio M. Exploring the role of skeletal muscle in insulin resistance: lessons from cultured cells to animal models. International Journal of Molecular Sciences. 2021 Aug 28;22(17):9327. Available:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8430804/ (accessed 17.4.2023)