Exercise-induced suppression of acylated ghrelin in humans

Abstract

Ghrelin is an orexigenic hormone secreted from endocrine cells in the stomach and other tissues. Acylation of ghrelin is essential for appetite regulation. Vigorous exercise induces appetite suppression, but this does not appear to be related to suppressed concentrations of total ghrelin. This study examined the effect of exercise and feeding on plasma acylated ghrelin and appetite. Nine male subjects aged 19-25 yr participated in two, 9-h trials (exercise and control) in a random crossover design. Trials began at 0800 in the morning after an overnight fast. In the exercise trial, subjects ran for 60 min at 72% of maximum oxygen uptake between 0800 and 0900. After this, they rested for 8 h and consumed a test meal at 1100. In the control trial, subjects rested for 9 h and consumed a test meal at 1100. Area under the curve values for plasma acylated ghrelin concentration (assessed from venous blood samples) were lower over the first 3 h and the full 9 h of the exercise trial compared with the control trial: 317+/-135 vs. 510+/-186 pg.ml(-1).3 h and 917+/-342 vs. 1,401+/-521 pg.ml(-1).9 h (means+/-SE) respectively (P<0.05). Area under the curve values for hunger (assessed using a visual scale) were lower over the first 3 h of the exercise trial compared with the control trial (P=0.013). These findings demonstrate that plasma acylated ghrelin concentration and hunger are suppressed during running.

Effect of acute and regular exercise on growth hormone secretagogue receptor-1a expression in human lymphocytes, T cell subpopulation and monocytes

“…In the present study, plasma levels of acylated ghrelin were temporarily suppressed after acute exercise, in accordance with previous literature (Broom et al, 2007;King et al, 2010).…”

“…Blood collected into the final tube was used for the determination of acylated ghrelin concentration, according to Broom et al (2007). This tube contained EDTA and phydroxymercuribenzoic acid to prevent the degradation of acylated ghrelin by protease.…”

Physiological and molecular responses to an acute bout of reduced-exertion high-intensity interval training (REHIT)

“…Following REHIT systemic concentrations of acylated ghrelin were reduced by >50% in the immediate post-exercise period, with little or no change observed following a bout of continuous cycling at a moderate intensity. This is consistent with other HIT studies (Sim et al 2013;Deighton et al 2013) and fits with previous research which highlights the key effect of relative exercise intensity on modulating the response of acylated ghrelin to aerobic exercise, with suppression occurring at higher (≥70% VȮ2max) but not lower (≤50% VȮ2max) exercise intensities (King et al 2010;Ueda et al 2009;Broom et al 2007;Broom et al 2009;Wasse et al 2013). Conversely, circulating levels of total PYY appear to be unaffected by REHIT.…”

Influence of resistance and aerobic exercise on hunger, circulating levels of acylated ghrelin, and peptide YY in healthy males

“…Currently, little is known about the influence of exercise on acylated ghrelin. Recently, we have shown that plasma acylated ghrelin is suppressed during vigorous treadmill running (9), while another recent study has reported increases in acylated ghrelin after five consecutive days of aerobic exercise (1 h/day) (36).…”