ABSTRACT
Weight loss of 7-18% following either lifestyle programs or bariatric surgery reduces ICAM-1, VCAM-1 and E-selectin by 15-28%, 15% and 20-35% respectively (Ferri et al. 1999, Ito et al. 2002, Pontiroli et al. 2004, Vazquez et al. 2005). However, the eff ect of weight loss on adhesion molecules is very variable. In a study by Pontiroli et al. (2008), BMI was reduced from 44.3 ± 0.43 to 36.4 ± 0.39 kg/m2 with a corresponding reduction in ICAM-1 concentrations from 313.1 ± 9.69 to 275.2 ± 6.16 ng/m (a 12% reduction). E-selectin was reduced from 64.1 ± 4.04 to 44.1 ± 1.96 ng/ml (a 31% reduction). Vazquez et al. (2005) observed that E-and P-selectin improved aft er weight loss of 24 kg, but ICAM-1 levels did not change and VCAM-1 increased, PAI-1 and CRP fell but TNF-alpha and IL6 did not change. Plat et al. (2007) in a study evaluating the eff ects of fi sh oil and moderate weight loss in 11 obese men (BMI 30-35 kg/m2) found that fi sh oil did not aff ect s-ICAM-1, whereas weight loss of 9.4 kg reduced fasting levels (p = 0.009) and post-prandial s-ICAM-1 responses (p < 0.001). A number of other studies have observed similarly mixed results (Ziccardi et al. 2002, Hamdy et al. 2003, Hanusch-Enserer et al. 2004, Pontiroli et al. 2004, Sharman and Volek 2004, Trøseid et al. 2005, McLaughlin et al. 2006, Konukoglu et al. 2007, Swarbrick et al. 2008). In a study of 18 morbidly obese patients who underwent gastric banding, subjects were evaluated before surgery and 6 and 12 mon aft er surgery. BMI dropped from 45.22 ± 5.62 to 36.99 ± 4.34 kg/m2 aft er 6 mon and to 33.72 ± 5.55 kg/m2 aft er 12 mon (both p < 0.0001). E-selectin levels decreased signifi cantly aft er 6 and 12 mon (p = 0.05), whereas signifi cantly lower levels of ICAM-1 and PAI-1 were seen aft er 6 mon but were not sustained at 12 mon. No changes were observed in VCAM-1 (Hanusch-Enserer et al. 2004). Th is was a small study and despite large weight loss these patients remain obese, which may explain the variability in the eff ects on adhesion molecules aft er maintenance of weight loss. Pontiroli et al. (2004) found that ICAM-1, E-selectin, and endothelin-1 (ET-1) were higher in 96 obese patients compared with 30 lean controls. In those 26
patients with type 2 diabetes, these variables were higher than in patients with normal (n = 43) or impaired (n = 27) glucose tolerance. Sixty-eight obese patients had signifi cant weight loss following bariatric surgery, with a decrease in these molecules to levels comparable with the lean controls. In 13 patients with a small weight loss achieved by diet the changes were not signifi cant. McLaughlin et al. (2006) observed that subjects (n = 57) who underwent 16 wk of an energy-restricted diet, 15% of energy as protein and either 60% and 25% or 40% and 45% of energy as carbohydrate and fat, showed weight loss of 5.7 ± 0.7 versus 6.9 ± 0.7 kg, respectively; subjects on the lower-carbohydrate (LC) diet (40% of energy) had greater decrease in plasma E-selectin than subjects on the higher-carbohydrate (HC) diet (60% of energy). ICAM-1 decreased aft er weight loss by 11% with no diff erence between diets. Hamdy et al. (2003) performed an uncontrolled study in 24 obese subjects in whom weight loss was 6.6 ± 1% and observed that sICAM decreased (251.3 ± 7.7 vs. 265.6 ± 9.3 ng/ml, p = 0.018). Sharman et al. (2004) in a study of 15 obese men who were allocated to two weight-loss diets for two consecutive 6 wk periods, either a very-low-carbohydrate diet (< 10% energy) or a low-fat diet (< 30% energy), observed that both diets resulted in signifi cant decreases in sICAM-1 with no change in sP-selectin concentrations. In 18 obese patients 1 mon aft er bariatric surgery, Konukoglu et al. (2007) found that weight loss was 13.2 kg and, while plasma sCRP and ADMA concentrations were signifi cantly decreased, they did not return to the same level as age-matched lean controls. VCAM-1 levels did not change aft er weight loss. Th ese patients remained obese despite the weight loss. In a study of 56 obese and 40 age-matched lean women compared with nonobese women, obese women had increased concentrations of TNF-alpha, IL-6, P-selectin, ICAM-1 and VCAM-1. TNF-alpha and IL-6 were related to visceral obesity. Weight loss (10%, 9.8 kg) was associated with reductions in TNF-alpha (30%), IL-6 (46%), P-selectin (30%), ICAM-1 (26%) and VCAM-1 (17%) (Ziccardi et al. 2002). Swarbrick et al. (2008), in a study of 19 obese women (BMI 45.6 ± 1.6 kg/m2), assessed weight before and 1 yr aft er Roux-en-Y gastric bypass surgery. Weight loss was 32% (40.5 kg) and IL6 fell by 49%, CRP by 77% and sICAM1 by 11%. Finally, the eff ect of physical exercise and pravastatin on levels of CAMs was evaluated in a study of 32 subjects (Trøseid et al. 2005). Subjects in the exercise group lost 0.7 BMI units and 7.5 cm in waist circumference. Changes in serum E-selectin were correlated with changes in BMI (r = 0.48, p = 0.006) and waist circumference (r = 0.48, p = 0.006) but not to changes in visceral or subcutaneous fat.
