IRISIN, OBESITY AND TYPE II DIABETES MELLITUS

Background: Irisin is an exercise-induced cytokine that is expressed as a biologically active peptide in many organs and tissues. Physical exercise and coldness are the main triggers for irisin release. Many studies have found that the levels of irisin are strongly correlated with health condition. Interestingly, irisin levels are higher in cancer patients but lower in patients with cardiovascular diseases, Alzheimer's disease, muscular atrophy, osteoporosis, and obesity. Irisin mediates glucose uptake in muscle cells, decreases insulin resistance, causes the 'browning' of the white adipocytes, enhances neural differentiation, and promotes osteoblast proliferation and differentiation through binding to the integrin αV/β5 receptor. Nevertheless, it is not completely known if it maintains glucose homeostasis, promotes neurogenesis, prevents cancer development, and regulates muscle regeneration by directly binding to its receptors. Objectives: Several studies aiming at the correlation between irisin levels and metabolic diseases have gained interest as a potential novel target to combat insulin resistance and type II diabetes mellitus (T2DM). Therefore, this review focuses on the molecular mechanisms of irisin and its impacts on obesity, glucose homeostasis, insulin resistance, and T2DM. Methodology: The data was collected through the electronic search of many scientific articles including, PubMed, Science Direct, and Google scholar. Results: Irisin has been shown to reduce insulin resistance and type II diabetes mellitus by enhancing insulin receptor sensitivity in the heart and skeletal muscle by improving lipid and glucose metabolism in the liver, enhancing pancreatic β-cell actions, and converting white to brown adipose tissue. Conclusion: Irisin has raised great hopes as a possible target in the conservative treatment of type II diabetes and obesity.