Department of Internal Medicine, Division of Cardiovascular Medicine, University of California, Davis, California, USA
* Corresponding author Email: email@example.com
Accounting for approximately half of the body weight, the skeletal muscle is the largest organ in the human body. The functional significance of the muscle is seen in the two-fold purpose it serves–as a source of force production for locomotion and as a major regulatory organ for glucose and fatty acid metabolism. This short review will focus on muscle fibre types, starting with a brief historical overview of fibre types, their physiological and metabolic significance, how fibre type plasticity affects both contractile and metabolic properties of muscle and how these properties relate to human diseases known to exhibit muscle fibre type (slow-twitch vs. fast-twitch) disproportion. Also, based on recent animal model experiments, this paper discusses the efficacy of using fibre type manipulation for therapeutic purposes.
Because of its adaptability to external stimuli and easy accessibility, skeletal muscle remodeling could be a viable therapeutic approach for various diseases manifesting fibre type shifts. Reduced ratios of slow-oxidative muscle are significantly associated with obesity and type 2 diabetes. Recent information obtained from animal model studies for metabolic syndrome and muscle atrophy present multiple candidate genes and signaling pathways for use as therapeutic targets. As more detailed molecular mechanisms of fibre type specification and plasticity are revealed, manipulating physiological properties of skeletal muscle holds a promise for treatment of obesity-induced clinical conditions as well as muscle atrophy.