Plasma ghrelin concentrations in elderly subjects: comparison with anorexic and obese patients

• Published in: Journal of endocrinology Vol. 175; no. 1; pp. R1 - R5
• Main Authors: Rigamonti, AE, Pincelli, AI, Corra, B, Viarengo, R, Bonomo, SM, Galimberti, D, Scacchi, M, Scarpini, E, Cavagnini, F, Muller, EE
• Format: Journal Article
• Language: English
• Published: Colchester BioScientifica 01.10.2002; Portland Press
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Aging - physiology; Anorexia Nervosa - blood; Biological and medical sciences; Body Mass Index; Female; Ghrelin; Humans; Insulin - blood; Insulin-Like Growth Factor I - analysis; Male; Medical sciences; Metabolic diseases; Obesity; Obesity - blood; Peptide Hormones - blood; Thyrotropin - blood; Human; Obesity; Metabolic disorder; Anorexia; Ghrelin; Nutrition disorder; Eating disorder; Elderly; Nutritional status
• ISSN: 0022-0795; 1479-6805
• DOI: 10.1677/joe.0.175r001

Ghrelin, a novel endogenous ligand for the GH secretagogue receptor, has been reported to stimulate GH secretion and food intake in both humans and other animals. Interestingly, recent data indicate that ghrelin is up- and down-regulated in anorexia nervosa (AN) and obesity, which are also known to be accompanied by increased and reduced GH levels respectively. Ageing is associated with a gradual but progressive reduction in GH secretion, and by alterations in appetite and food intake. The role of ghrelin in the decline of somatotroph function and the anorexia of ageing is unknown. To investigate the influence of age on circulating levels of ghrelin, a total of 19 young and old normal weight subjects (Y-NW, n=12; O-NW, n=7), six patients with active AN (A-AN), and seven patients with morbid obesity (OB) were studied. In addition to fasting plasma ghrelin concentrations, baseline serum TSH, IGF-I and insulin levels were measured. Mean plasma ghrelin concentrations in A-AN or OB were higher and lower respectively than those present in Y-NW. Interestingly, mean plasma ghrelin concentrations in O-NW were significantly lower than those present in Y-NW and superimposable on those of OB. The mean fasting plasma ghrelin concentrations in all groups of subjects were negatively correlated with body mass index and serum insulin levels, but not with TSH and IGF-I levels. This study provides evidence of an age-related decline of plasma ghrelin concentrations, which might explain, at least partially, the somatotroph dysregulation and the anorexia of the elderly subject.