Reduction of sleeping metabolic rate after vertical banded gastroplasty

Department of Surgery, University Hospital Maastricht, The Netherlands. OBJECTIVE: To investigate whether long-term weight loss after vertical banded gastroplasty (VBG) results in a sustained reduction of sleeping metabolic rate (SMR) as a persistent risk factor for weight regain. DESIGN: Longitudinal clinical intervention study of morbidly obese patients undergoing VBG. PATIENTS: Group I: Six patients in which body composition and SMR were measured before and at 3, 6 and 12 months after VBG. Group II (long-term effect): nine patients in which body mass (BM) was measured before VBG, and body composition and SMR were measured 98+/-30 months after VBG. MEASUREMENTS: Body composition was assessed by deuterium dilution and hydrostatic weighing. SMR was measured (SMRm) in a respiration chamber and predicted (SMRp) based on body composition. RESULTS: In group I, fat mass and fat free mass decreased significantly after VBG (P < 0.05). SMRm decreased from 11.1+/-1.8 (s.d.) MJ/d before VBG to 8.1+/-0.9 MJ/d (P < 0.05) at 12 months after VBG. In group II at a mean of 98 months after VBG, the SMRm (6.9+/-0.7 MJ/d) was lower than the preoperative value of group I (P < 0.05). SMRm was lower than SMRp at all intervals after VBG (P < 0.05). The ratio measured vs predicted SMR was in group I: 1.02+/-0.05 before VBG, 0.91+/-0.08 at 12 months after VBG (P<0.05), and in group 11: 0.94+/-0.08 at a mean of 98 months after VBG (P < 0.05). CONCLUSION: The reduction of SMR adjusted for body composition after VBG is sustained as long as weight loss is maintained. The sustained and disproportional reduction of SMR may reflect the persistent susceptibility of the postobese to weight regain

Decreased plasma orexin-A levels in obese individuals

Orexin-A and -B stimulate appetite and food intake in rats. Orexins and orexin receptors are present in the hypothalamus as well as the enteric nervous system, the pancreas and the gut. The presence of orexins in peripheral blood, however, has not yet been reported. To determine whether orexin-A is present in human plasma and is related to body weight, we measured plasma orexin-A and leptin levels in a population with a body mass index (BMI) range from 19.8 to 59 kg/m(2). Plasma orexin-A levels correlated negatively and plasma leptin levels correlated positively with BMI. In obese and morbidly obese individuals, orexin-A levels were significantly lower and leptin levels were significantly higher when compared to normal. Our results support previous data suggesting that orexin-A acts also in a peripheral manner. The fact that lower levels of plasma orexin-A are present in obese individuals suggests that it is involved in the regulation of human energy metabolis

Increased leptin concentrations correlate with increased concentrations of inflammatory markers in morbidly obese individuals

OBJECTIVE: To study whether an increase of plasma leptin concentrations, as observed in the case of increased body weight, is associated with an inflammatory state. SUBJECTS: Sixty-three healthy subjects with body mass index (BMI) ranging from 20 to 61 kg/m2. MEASUREMENTS: Plasma concentrations of leptin, the inflammatory parameter soluble TNF-alpha receptors (TNFR55 and TNFR75), the acute phase proteins lipopolysaccharide binding protein (LBP), serum amyloid A (SAA), alpha-acid glycoprotein (AGP), C-reactive protein (CRP), plasminogen activator inhibitor-1 (PAI-1) and the anti-inflammatory soluble Interleukin-1 decoy receptor (sIL-1RII) were measured. RESULTS: As expected, BMI correlated significantly with leptin (r=0.823, P <0.001), but also with all acute phase proteins, both soluble TNF receptors and PAI concentrations. After correction for BMI and sex, no significant correlation between leptin and the acute phase proteins was seen. Interestingly, however, leptin strongly correlated with both TNF receptors (r=0.523, P <0.001 for TNFR55 and r=0.438, P <0.001 for TNFR75). CONCLUSIONS: This study shows the development of a pro-inflammatory state with increasing body weight. The BMI independent relationship between leptin and both soluble TNF-receptors is consistent with a regulatory role for leptin in the inflammatory state in morbidly obese subject