Increased activity of interleukin-23/interleukin-17 proinflammatory axis in obese women

Objective: To compare the concentrations of cytokines belonging to Th17 axis ( interleukin (IL)-17 and IL-23) and Th1 axis (IL-12 and interferon (IFN)-gamma) in obese and lean women, and to investigate their relationships with the proinflammatory adipokine leptin, proinflammatory cytokine macrophage migration inhibitory factor (MIF) and anthropometric and metabolic parameters of obesity. Design: Cross-sectional study. Subjects: Twenty-six obese women (age 20-52 years, body mass index (BMI): 30-48 kg/m(2)) and 20 healthy lean women (age 23-46 years, BMI: 18-25 kg/m(2)). Measurements: Plasma levels of cytokines and leptin, BMI, waist circumference ( WC) and insulin resistance index HOMA (homeostatic model assessment). Results: Blood concentrations of IL-17, IL-23, MIF and leptin, but not IL-12 or IFN-gamma, were higher in obese compared with lean women (P = 0.002, 0.046, 0.006 and 0.002, respectively). There was a positive correlation between IL-17 and IL-23 (r(s) = 0.530), which was at the border of statistical significance (P = 0.065). Neither IL-17 nor IL-23 correlated with leptin or MIF, and there was no association between IL-17 and IL-23 levels with BMI, WC or HOMA index. Conclusion: Interleukin-23/IL-17 axis is stimulated in obese women independently of the increase in abdominal fat, insulin resistance, leptin and MIF levels.