Circulating Irisin in Relation to Insulin Resistance and the Metabolic Syndrome

• Published in: The journal of clinical endocrinology and metabolism Vol. 98; no. 12; pp. 4899 - 4907
• Main Authors: Hee Park, Kyung, Zaichenko, Lesya, Brinkoetter, Mary, Thakkar, Bindiya, Sahin-Efe, Ayse, Joung, Kyoung Eun, Tsoukas, Michael A., Geladari, Eleni V., Huh, Joo Young, Dincer, Fadime, Davis, Cynthia R., Crowell, Judith A., Mantzoros, Christos S.
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Oxford University Press 01.12.2013; Copyright by The Endocrine Society; Endocrine Society
• Subjects: Adiponectin; Adiponectin - blood; Adult; Biological and medical sciences; Biomarkers - blood; Blood pressure; Body Mass Index; Boston - epidemiology; Cardiovascular diseases; Cardiovascular Diseases - epidemiology; Cardiovascular Diseases - etiology; Cholesterol; Cross-Sectional Studies; Endocrine Research; Endocrinopathies; Energy balance; Fasting; Feeding. Feeding behavior; Female; Fibronectins - blood; Fundamental and applied biological sciences. Psychology; High density lipoprotein; Homeostasis; Humans; Insulin Resistance; Male; Medical sciences; Metabolic syndrome; Metabolic Syndrome - blood; Metabolic Syndrome - complications; Metabolic Syndrome - epidemiology; Metabolic Syndrome - physiopathology; Middle Aged; Models, Biological; Overweight - complications; Risk Factors; Triglycerides; Up-Regulation; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Vertebrates: endocrinology; Endocrinopathy; Obesity; Pancreatic hormone; Nutrition; Nutrition disorder; Cardiovascular disease; Metabolic diseases; Metabolic syndrome; Insulin; Target tissue resistance; Insulin resistance; Endocrinology; Nutritional status
• ISSN: 0021-972X; 1945-7197; 1945-7197
• DOI: 10.1210/jc.2013-2373

Context:Irisin, a recently identified hormone, has been proposed to regulate energy homeostasis and obesity in mice. Whether irisin levels are associated with risk of the metabolic syndrome (MetS), cardiometabolic variables, and cardiovascular disease (CVD) risk in humans remains unknown.Objective:Our objective was to assess the associations between baseline serum irisin levels and MetS, cardiometabolic variables, and CVD risk.Design, Setting, and Subjects:We conducted a comparative cross-sectional evaluation of baseline circulating levels of the novel hormone irisin and the established adipokine adiponectin with MetS, cardiometabolic variables, and CVD risk in a sample of 151 subjects.Results:Baseline irisin levels were significantly higher in subjects with MetS than in subjects without MetS. Irisin was associated negatively with adiponectin (r = −0.4, P < .001) and positively with body mass index (r = 0.22, P = .008), systolic (r = 0.17, P = .04) and diastolic (r = 0.27, P = .001) blood pressure, fasting glucose (r = 0.25, P = .002), triglycerides (r = 0.25, P = .003), and homeostasis model assessment for insulin resistance (r = 0.33, P < .001). After adjustment for potential confounders, including body mass index, subjects in the highest tertile of irisin levels were more likely to have MetS (odds ratio [OR] = 9.44, 95% confidence interval [CI] = 2.66–33.44), elevated fasting blood glucose (OR = 5.80, 95% CI = 1.72–19.60), high triglycerides (OR = 3.89, 95% CI = 1.16–13.03), and low high-density lipoprotein cholesterol (OR = 3.30, 95% CI = 1.18–9.20). Irisin was independently associated with homeostasis model assessment for insulin resistance and general Framingham risk profile in multiple linear regression analyses after adjustment for confounders. Adiponectin demonstrated the expected associations with outcomes.Conclusions:Irisin is associated with increased risk of MetS, cardiometabolic variables, and CVD in humans, indicating either increased secretion by adipose/muscle tissue and/or a compensatory increase of irisin to overcome an underlying irisin resistance in these subjects.