Increased levels and adipose tissue expression of visfatin in morbidly obese women: the relationship with pro-inflammatory cytokines

Objective The controversial results on the physiopathological role of visfatin led us to examine both circulating visfatin levels and gene expression in visceral (VAT) and subcutaneous fat (SAT) in a homogeneous group of morbidly obese women. Design, patients and measurements We analysed circulating levels of several adipo/cytokines in 133 Spanish women: 40 lean (C) [body mass index (BMI) < 25 kg/m2] and 93 morbidly obese (MO) (BMI > 40 kg/m2). In the MO group, we found 31 diabetic and 62 nondiabetic subjects. We obtained follow-up blood samples at 6 and 12 months after bariatric surgery from 30 MO patients. We determined the circulating levels of visfatin, adiponectin, interleukin-6 (IL6), C-reactive protein (CRP), resistin and tumour necrosis factor-a (TNFa) by ELISA, and visfatin, adiponectin, IL6, resistin and TNFa gene expression in SAT and VAT by real-time RT-PCR. Results Circulating visfatin levels were higher in MO women compared with lean controls (C = 1.43 +/- 0.14 mu g/l, MO = 3.60 +/- 0.29 mu g/l, P < 0.001). After bariatric surgery-induced weight loss, visfatin levels were reduced significantly over 12 months. Visfatin expression in SAT and VAT was similar, but significantly higher in MO compared to C and independent of the presence of diabetes mellitus. Circulating visfatin levels were positively related to IL6 and CRP levels. Visfatin gene expression in VAT and SAT was strongly related to IL6 and TNFa expression. Conclusion In a homogeneous cohort of morbidly obese women, our findings show that visfatin has a strong relationship with pro-inflammatory factors in severe obesity.