Effects of age, malnutrition and refeeding on the expression and secretion of ghrelin.
OBJECTIVE
Anorexia is frequent in the malnourished elderly. We studied the effects of age, nutritional status and refeeding on the expression and secretion of the orexigenic peptide ghrelin.


METHODS
Four groups were prospectively enrolled: 11 undernourished elderly (80+/-6 y, BMI: 17.4+/-1.9 [Mean+/-SD]), nine well-nourished elderly (76+/-9 y, 23.5+/-2.0), 10 undernourished young (26+/-6 y, 15.1+/-1.9) and 10 well-nourished young (34+/-8 y, 22.2+/-2.7). Fasting and postprandial plasma ghrelin and other hormones (every 30 min) were measured at baseline and after a 21-day enteral nutrition in malnourished patients. Gastric ghrelin mRNA levels were measured by RT-PCR at baseline in all subjects.


RESULTS
Ghrelin was significantly higher in undernourished (2151+/-871 ng/L) than in well-nourished (943+/-389 ng/L) adults, whereas there were no differences between undernourished (1544+/-758 ng/L) and well-nourished (1154+/-541 ng/L) elderly. Refeeding did not influence ghrelin levels. Gastric ghrelin mRNA levels were similar in all groups.


CONCLUSIONS
There is an absence of malnutrition-induced increase of plasma ghrelin levels in elderly subjects. This feature, post-transcriptional, may be important in the lack of adaptation of elderly subjects to malnutrition.
Schneider
Stéphane M
SM
Université de Nice-Sophia-Antipolis, Faculté de Médecine, Nice F-06107, France. stephane.schneider@unice.fr
Al-Jaouni
Rima
R
Caruba
Céline
C
Giudicelli
Jean
J
Arab
Kamel
K
Suavet
Florence
F
Ferrari
Patricia
P
Mothe-Satney
Isabelle
I
Van Obberghen
Emmanuel
E
Hébuterne
Xavier
X
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D000855:Anorexia / Q000097:blood; D004750:Enteral Nutrition; D005215:Fasting; D005502:Food; D054439:Ghrelin / Q000097:blood* / Q000235:genetics; D006801:Humans; D044342:Malnutrition / Q000097:blood*; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013270:Stomach / Q000737:chemistry
D054439:Ghrelin; D012333:RNA, Messenger