Changes of body weight and plasma ghrelin levels after gastric banding and gastric bypass.
OBJECTIVE
Ghrelin is an enteric peptide with strong orexigenic and adipogenic effects. Plasma ghrelin levels are decreased in obese subjects but increase after weight loss; this increase is not observed after Roux-en-Y gastric bypass (RYGB). Prospective and comparative data after adjustable silicone gastric banding (ASGB) have not been reported previously.


METHODS
Overnight fasting plasma ghrelin concentration was measured in morbidly obese subjects at baseline and 3, 6, 12, and 24 months after ASGB (n = 8) or RYGB (n = 5) and in nonoperated controls (n = 7).


RESULTS
After RYGB, body weight (BW) decreased by 29.5 +/- 5.5 kg (mean +/- SE, p < 0.001), whereas plasma ghrelin failed to increase significantly (+167 +/- 119 pg/mL, not significant). In contrast, after ASGB, BW decreased less (by 22.8 +/- 5.9 kg; p < 0.001), and plasma ghrelin significantly increased by 377 +/- 201 pg/mL (p = 0.025). Neither BW nor plasma ghrelin changed in nonoperated controls. Plasma leptin decreased in both operated groups (similarly p < 0.05) but not in nonoperated controls. Plasma growth hormone and insulin-like growth factor 1 were not correlated with changes in plasma ghrelin concentrations.


CONCLUSIONS
Plasma ghrelin levels failed to increase during substantial weight loss after RYGB, but did increase in response to lesser weight loss after ASGB. These findings suggest that the plasma ghrelin response after weight loss is impaired after exclusion of major parts of the stomach and the duodenum (RYGB), and the smaller long-term weight loss after ASGB compared with RYGB may be due, at least in part, to an absent increase in plasma ghrelin after RYGB.
Division of Endocrinology, Diabetology, and Clinical Nutrition, University Hospital Basel, 4031 Basel, Switzerland.
Rolf
R
Stoeckli
Robin
R
Chanda
Igor
I
Langer
Ulrich
U
Keller
D000328:Adult; D000713:Anastomosis, Roux-en-Y; D015992:Body Mass Index; D015390:Gastric Bypass; D054439:Ghrelin; D006801:Humans; D008875:Middle Aged; D009767:Obesity, Morbid / Q000097:blood* / Q000601:surgery*; D036361:Peptide Hormones / Q000097:blood*; D011184:Postoperative Period; D013270:Stomach / Q000601:surgery*; D015431:Weight Loss / Q000502:physiology*
D054439:Ghrelin; D036361:Peptide Hormones