One Year of Yoga Training Alters Ghrelin Axis in Centrally Obese Adults With Metabolic Syndrome

Abstract

Introduction: Metabolic syndrome (MetS) is a multiplex cardiometabolic manifestation associated with type 2 diabetes mellitus and cardiovascular diseases. Yoga training has been shown to alleviate MetS. Recently, circulatory ghrelin profile was demonstrated to be associated with MetS. This study examined the effects of 1 year of yoga training on β-cell function and insulin resistance, and the involvement of metabolic peptides, including unacylated ghrelin (UnAG), acylated ghrelin (AG), obestatin, growth hormone (GH), and insulin, in the beneficial effects of yoga training in centrally obese adults with MetS.Methods: This was a follow up study, in which data of risk factors of MetS, physical performance tests [resting heart rate (HR), chair stand test (CS), chair sit and reach test (CSR), back scratch test (BS), and single leg stand tests (SLS)] and serum samples of 79 centrally obese MetS subjects aged 58 ± 8 years (39 subjects received 1-year yoga training and 40 subjects received no training) were retrieved for analyses. β-cell function and insulin resistance were examined by Homeostasis Model Assessment (HOMA). Circulating levels of UnAG, AG, obestatin, GH, and insulin were determined by enzyme-linked immunosorbent assay using fasting serum samples. Generalized estimating equation analysis and Mann–Whitney U-test were used to detect statistically significant differences between groups.Results: Waist circumference (WC) was significantly decreased after yoga intervention (control: +2%; yoga: -4%). Significant improvements in HR (control: +2%; yoga: -5%), CS (control: -1%; yoga: +24%), CSR left (control: worsen by 0.90 cm; yoga: improved by 4.21 cm), CSR right (control: worsen by 0.75 cm; yoga: improved by 4.28 cm), right side of BS (control: improved by 0.19 cm; yoga: improved by 4.31 cm), SLS left (control: -10%; yoga: +86%), and SLS right (control: -6%; yoga: +47%) were observed after 1-year yoga training. No significant difference was found between the two groups in insulin, HOMA indices, and disposition index. Yoga training significantly increased circulating GH (control: -3%; yoga: +22%), total circulating ghrelin (control: -26%; yoga: +13%), and UnAG (control: -27%; yoga: +14%), whereas decreased AG (control: -7%; yoga: -33%) and obestatin (control: +24%; yoga: -29%).Conclusion: One-year of yoga training modulated total ghrelin, UnAG, AG, obestatin, and GH while exerting beneficial effects on physical functions and central obesity in adults with MetS. The beneficial effects of yoga may be associated with the alteration of ghrelin gene product and GH.

Ghrelin Response to Acute and Chronic Exercise: Insights and Implications from a Systematic Review of the Literature

“…Participants were normal weight people in 46 studies, overweight/obese people in 28 studies, and both groups in two studies. Five studies involved clinical populations, including GH-deficient [ 46 ], hemodialysis [ 55 , 124 ], and metabolic syndrome [ 103 , 111 ] patients. Regarding fitness/training level, 33 studies involved inactive untrained subjects, 23 studies involved mildly to moderately active subjects, and 24 studies involved well-trained athletes.…”

“…Four studies showed no change in AG in either normal weight [ 100 , 109 ] or overweight/obese [ 105 , 107 ] subjects who underwent short-term [ 100 ] or long-term [ 105 , 107 , 109 ] moderate-intensity aerobic training programs. Three studies involving active normal weight [ 109 ] or obese [ 108 , 111 ] individuals showed a decrease in AG with long-term or very long-term [ 108 , 109 , 111 ] moderate-intensity aerobic training.…”

Outcomes from a Whole-Systems Ayurvedic Medicine and Yoga Therapy Treatment for Obesity Pilot Study

“…29 Yoga is inexpensive, noninvasive, and has been determined by two comprehensive reviews of clinical trials to be a safe effective intervention to reduce BMI and effective as primary or supplemental self-care for weight loss, weight maintenance, and prevention of obesity and metabolic syndrome. 30,31 Other studies of yoga for weight loss/metabolic syndrome/diabetes have found significant reductions in abdominal obesity, 32 positive alterations in ghrelin axis, 33 and a reduction in cardiometabolic risk factors. 34 The specific mind-body approach of yoga therapy has also been found to spur psychosocial changes associated with durable weight loss, including ''yoga culture'' social support and reports that a yogic experience of weight loss was ''easier'' and ''subjects felt more confident in their ability to maintain lasting weight loss.''…”

“…Yoga therapy treats obesity through postures, breathing techniques, and meditation that improve muscle tone, reduce fat, regulate the nervous system and psychoemotional states, and detoxify tissues/improve metabolism. [30][31][32][33][34] Ayurvedic Yoga further addresses obesity by counteracting the slow, static, cold, heavy, and dense qualities. 22,23 The intervention was designed to change eating and activity patterns and to improve self-efficacy, quality of life/well-being, vitality, stress management, self-awareness around food choices, and barriers to weight loss.…”

Quality of Life in Yoga Experienced and Yoga Naïve Asian Indian Adults with Obesity

“…Yoga is one such intervention with studies reporting long-term adherence and benefits in various health conditions including obesity [16, 17]. Effects of yoga on the quality of life were seen in a single-arm interventional study on 279 overweight and obese Asian Indian persons of both sexes aged between 20 and 60 years who showed a significant improvement in physical, psychological, and environmental domains of the quality of life based on the World Health Organization Quality of Life Instruments (WHOQOL-BREF) questionnaire, after 10 days of a yoga-based lifestyle intervention [18].…”