Muscles and their myokines.
1Centre of Inflammation and Metabolism, Rigshospitalet-Section 7641, Blegdamsvej 9, DK-2100, Copenhagen, Denmark. bkp@rh.dk
The Journal of Experimental Biology
|December 24, 2010
Summary
Physical activity offers protection against chronic diseases like diabetes and dementia. Contracting skeletal muscles release myokines, acting as hormones to benefit overall health.
Area of Science:
- Exercise physiology
- Endocrinology
- Molecular biology
Background:
- Physical activity traditionally viewed for energy balance and obesity prevention.
- Growing evidence links physical activity to protection against chronic diseases, including type 2 diabetes, cardiovascular diseases, cancer, dementia, and depression.
- Previous research sought an 'exercise factor' mediating metabolic changes induced by muscle contraction.
Purpose of the Study:
- To introduce and define 'myokines' as signaling proteins secreted by skeletal muscle.
- To establish skeletal muscle as an endocrine organ.
- To explore the role of myokines in mediating exercise-induced health benefits.
Main Methods:
- Conceptual framework development based on existing epidemiological and physiological evidence.
- Definition and classification of myokines.
- Hypothesizing the endocrine and paracrine functions of myokines.
Main Results:
- Skeletal muscle releases myokines, which function similarly to hormones.
- Myokines exert endocrine effects on distant organs and paracrine effects within muscle tissue.
- Myokines are proposed mediators of exercise-induced protection against chronic diseases.
Conclusions:
- Skeletal muscle functions as an endocrine organ through the secretion of myokines.
- Myokines play a crucial role in the systemic health benefits of physical activity.
- Further research into myokines may reveal novel therapeutic targets for chronic diseases.
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