Effects of Diet and Exercise-Induced Weight Loss in Sedentary Obese Women on Inflammatory Markers, Resistin, and Visfatin

Resistin and Visfatin are secreted by adipose tissue and are potential regulators of inflammation and insulin sensitivity. This study examined the effects of exercise and diet-induced weight loss on resistin and visfatin. Twenty six sedentary obese women were randomly assigned into a non-exercise and diet intervention control group (C) or a diet plus exercise group (DE) that involved adherence to a 1,200 kcal/day for 1 week and 1,500 kcal/d diet for 11 weeks (45% protein, 30% fat) while participating in a supervised circuit resistance-exercise (4 d/week) with walking (10,000 steps/d, 3 d/week). Body composition and fasting blood samples were obtained at 0 and 12 weeks and analyzed by multivariate, univariate, and repeated measures General Linear Model analysis and bivariate Pearson product correlation analysis. Data are presented as mean±SD changes from baseline. Participants in the DE group lost more weight (DE: -5.9±4.0; C: 0.6±1.4 kg, p<0.001), fat mass (DE: -5.1±4.5; C: 0.4±1.5 kg, p<0.001) and body fat percentage (DE: -3.4±3.3; C: 0.2±1.9 kg, p=0.002) with significant decreases in insulin (DE: -8.5±15.0; C: 0.1±7.7 IU/ml, p=0.07, ηp2 = 0.13), IL-6 (DE: -1.9±4.2; C: 2.7±1.2 ng/ml, p=0.001), TNFα (DE: -0.2±2.1; C: 1.7±1.5 ng/ml, p<0.01), and leptin (DE: -19.8±21.9; C: 4.5±16.0 ng/ml, p=0.003) while tending to prevent decreases in visfatin (DE: 0.9±15; C -20.1±37 ng/ml, p=0.10, ηp2= 0.10). No effects were seen on glucose (DE: -3.8±19.8; C: -2.8±6.9 mg/dl, p=0.87) and resistin levels (DE: 18.6±100; C: 59.9±162 ng/ml, p=0.45). Changes in resistin significantly correlated with IL-6 and visfatin. Linear regression analysis revealed significant correlations between changes in resistin to visfatin (r=0.42, R2=0.174, p=0.034) and resistin to IL-6 (r=0.43, R2=0.185, p=0.028). Results support contentions that diet and exercise-induced weight loss affects insulin sensitivity and inflammatory markers and that changes in resistin and visfatin may be correlated with some of these changes.