Ever wondered about a hormone that is a pro-myogenic factor that makes you gain muscle? Decrease body fat and improve lipid profile? And does it help regulate energy homeostasis? Discovered in 2012, irisin is the new hormone most studied to reduce several problems such as cardiovascular disease, diabetes, osteopenia, sarcopenia among others.
What is irisin?
It is a hormone secreted by muscle cells to act as a bridge between physical exercise and metabolic homeostasis, the amount of circulating irisin is proportional to the amount of lean mass. Studies have shown that subjects who did endurance exercise for 10 weeks had the level of the hormone doubled.
It has action in various locations of our body such as muscle, adipose tissue, bones, liver and nervous system. Irisin is not only a myocin but also an adipokine, it acts as a transcription factor in several different cells.
During physical exercise microlesions occur in the muscle cells that produce substances that warn the body that that fiber needs repair, at that moment Irisin plays a fundamental role. One study showed that there is a relationship between the level of Irisin and increase of IGF-1 and reduction of myostatin, key substances for muscle hypertrophy.
Effects of irisin
In the Adipose Tissue it acts transforming the cells of white fat into brown fat, activating the transcription of a protein called UCP1 when this occurs the stored fat is mobilized more easily for the firing, that is, it has thermogenic effect. In this way Irisin can be a fundamental factor in weight loss and related diseases such as dyslipidemia, diabetes, hypertension among others. In addition, Irisin inhibits adipogenesis which is the mechanism by which fats are stored in adipose tissue, in other words, it prevents fat from accumulating.
Irisin also has an effect on bone metabolism. In rat studies, this hormone has decreased the action of osteoblast inhibitors that prevent bone regeneration. In that same study, rats supplemented with r-irisin had their osteopontin levels increased, this glycoprotein is essential for the biomineralization of bones, as well as decreases the presence of sclerostin a substance that prevents bone formation. Another incredible effect of this hormone on bones is the differentiation of osteoblasts in bone marrow.
It is also produced in the nervous tissue, more precisely in the Purkinje cells and is necessary for the correct differentiation of stem cells in embryonic nervous tissue, also has action in hippocampal neurogenesis and increases the proliferation of neurons in this region that is most affected by Alzheimer’s disease.
How to increase the hormone production?
Unfortunately the irisin hormone is not something that can be found in capsules or in a plant, exercising your body is the main way to increase irisin production.
Nutrition affects the production of irisin, the consumption of polyunsaturated fatty acids like omega-3 has a positive effect on the levels of this hormone. A study by the International Journal of Endocrinology and Metabolism showed that supplementation of 1.2g of omega-3s three times daily increases the serum irisin level in diabetic subjects.
Irisin has an effect on the decrease in insulin resistance, it acts as a transcription factor for Glut-4 in the muscles which is a transporter of glucose into the muscles, consequently lowering glycemia.
It is produced by muscle cells through the expression of the Ppargc1a gene that encodes the expression of PGC1α, which in turn will stimulate the expression of the FDNC5 which is the precursor of irisin.
There is still a lot of research to be done with this new hormone since it was only discovered in 2012, but the few results found show the benefits of this hormone to overall health. The good side of all this is that this hormone is synthesized from the trained muscle, plus evidence that physical activity is essential for health.
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