FABP 4 is associated with inflammatory markers and metabolic syndrome in morbidly obese women

<jats:sec><jats:title>Objective</jats:title><jats:p>The adipocyte/macrophage fatty acid-binding protein 4 (FABP4) has been described as a biomarker for adiposity and metabolic syndrome (MS). The aims of this study were to assess the relationship between FABP4 and inflammatory cytokines related to obesity, and to evaluate <jats:italic>FABP4</jats:italic> mRNA expression in visceral and subcutaneous adipose tissue in non-diabetic morbidly obese women versus healthy lean women.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>We analyzed circulating levels of FABP4 in 81 Spanish women: 38 lean (body mass index (BMI)<25 kg/m<jats:sup>2</jats:sup>) and 43 morbidly obese (BMI>40 kg/m<jats:sup>2</jats:sup>). We took 30 follow-up blood samples at 6 and 12 months after bariatric surgery. We assessed <jats:italic>FABP4</jats:italic> gene expression in samples of subcutaneous abdominal and visceral adipose tissue. Adipose tissue mRNA expression was determined by real-time RT-PCR.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>In morbidly obese women, plasma FABP4 levels were significantly higher than in non-obese patients. These levels positively correlated with BMI, homeostasis model assessment of insulin resistance (HOMA2-IR), and plasma glucose and insulin levels. Post-operative FABP4 levels decreased by a maximum of 30% after 12 months. We also found an inverse association between FABP4 and adiponectin levels, and positive correlations between FABP4 and circulating leptin, tumor necrosis factor (TNF) receptors, C-reactive protein (CRP) and interleukin 6 levels. Linear regression analysis revealed that FABP4 was more closely related to HOMA2-IR than adiponectin, CRP, TNF-RI, or leptin. Furthermore, high circulating FABP4 levels were associated with the presence of MS. <jats:italic>FABP4</jats:italic> mRNA expression in visceral adipose tissue was related to its circulating levels in morbidly obese women.</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>Our results indicate that serum FABP4 is associated with inflammatory factors related to obesity and MS in non-diabetic morbidly obese women.</jats:p></jats:sec>