title: Circulating ghrelin is sensitive to changes in body weight during a diet and exercise program in normal-weight young women.
abstract: Ghrelin is directly involved with short-term regulation of energy balance. Although circulating levels of ghrelin are elevated in anorexia nervosa and reduced in obesity, the role of ghrelin in regulating long-term energy balance in healthy women has not been investigated. We examined the effects of a 3-month energy deficit-imposing diet and exercise intervention on circulating ghrelin in normal-weight, healthy women. Body composition, resting metabolic rate, and serum ghrelin were measured at pre-, mid-, and postintervention in controls (n = 7), who performed no exercise, and exercising women who remained weight stable (n = 5) or lost weight (n = 10). Exercise training occurred five times per week, and subjects were fed a specific diet. Ghrelin significantly increased over time (770 +/- 296 to 1322 +/- 664 pmol/liter) in the weight-loss group compared with the controls and the weight-stable group (P < 0.05). Changes in ghrelin were negatively correlated with changes in body weight (r = -0.61; P < 0.05). Body fat, body weight, and resting metabolic rate significantly decreased in the weight-loss group before the increase in ghrelin. These findings suggest that ghrelin responds in a compensatory manner to changes in energy homeostasis in healthy young women, and that ghrelin exhibits particular sensitivity to changes in body weight.
authors.affiliation: Noll Physiological Research Center and the Department of Kinesiology, Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: H J
authors.initials: HJ
authors.lastname: Leidy
authors.forename: J K
authors.initials: JK
authors.lastname: Gardner
authors.forename: B R
authors.initials: BR
authors.lastname: Frye
authors.forename: M L
authors.initials: ML
authors.lastname: Snook
authors.forename: M K
authors.initials: MK
authors.lastname: Schuchert
authors.forename: E L
authors.initials: EL
authors.lastname: Richard
authors.forename: N I
authors.initials: NI
authors.lastname: Williams
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism; D000293:Adolescent; D000328:Adult; D015992:Body Mass Index; D001835:Body Weight / Q000502:physiology*; D002940:Circadian Rhythm / Q000502:physiology; D004032:Diet; D002149:Energy Intake / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D005260:Female; D054439:Ghrelin; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D036361:Peptide Hormones / Q000097:blood*; D011446:Prospective Studies
chemical_list: D054439:Ghrelin; D036361:Peptide Hormones