The relationships between IGF-1 and CRP, NO, leptin, and adiponectin during weight loss in the morbidly obese

Background The relationship between C-reactive protein (CRP), nitric oxide (NO), leptin, adiponectin, and insulin growth factor 1 (IGF-1) is poorly defined in morbidly obese patients before and after gastric bypass and, in some cases, is controversial. Methods We examined the plasma of 34 morbidly obese patients before and 1, 6, and 12 months after Roux-en-Y gastric bypass surgery. Results Obese people had more CRP (21.3 ±1.8 μg/ml) and leptin (36.9±4.0 μg/ml) man those in the control group (nonobese people: CRP= 6.9±0.9 μg/ml, p<0.0001; leptin= 7.5±0.4 μg/ml, p<0.0001). However, they had less NO (30.4±2.7 nmol/ml), IGF-1 (77.5±6.6 ng/ml), and adiponectin (11.1 ±1.0 μg/ml) than those in the control group (NO= 45.8±3.9 nmol/ml, p=0.0059; IGF-1 = 202.0± 12.0 ng/ml, p<0.0001; adiponectin= 18.0±2.0 μg/ml, p< 0.0001). During weight loss, the amount of CRP and leptin decreased until they reached the nonobese values, but the level of NO remained lower than in nonobese people, even 1 year after surgery. The linear regression slopes were negative and very significant for leptin (p=0.0005) and CRP 0=0.0018) but were less significant for NO (p= 0.0221). IGF-1 displayed a very good linear regression (both negative and significant) with some anthropometric parameters, including body mass index (p=0.0025), total fat p=0.0177), and the percentage of fat (p<0.0001). Conclusion For the first time, we report the relationship between IGF-1 and CRP, NO, leptin, and adiponectin. For all these parameters, the best and most widely demonstrated improvements in comorbidities before and during weight loss in morbid obesity were associated with CRP and leptin. © 2010 Springer Science+Business Media, LLC.