Systemic low-grade inflammation is related to both circulating and adipose tissue TNFα, leptin and IL-6 levels in obese women

OBJECTIVE: We assessed the relationships between four circulating acute phase proteins and the circulating and adipose tissue levels of three adipocytokines. SUBJECTS: In all, 15 nondiabetic obese women with a body mass index (BMI) above 32 kg/m(2) were investigated. METHOD: Circulating concentrations of C-reactive protein (CRP), alpha 1 acid glycoprotein (AAG), fibrinogen, alpha 1 antitrypsin and both circulating and adipose tissue levels of interleukin (IL)-6, tumor necrosis factor (TNF) alpha and leptin were measured by either nephelometry or enzyme-linked immunosorbent assay. RESULTS: We found a strong positive correlation between both circulating and adipose tissue levels of IL-6, TNFalpha and leptin and serum CRP levels. All these adipose tissue adipocytokines were also positively correlated with serum AAG levels. These correlations disappeared when adjusted for fat mass, suggesting that the relationship observed was dependent on fat amount. CONCLUSION: Our results indicate a strong relationship between adipocytokines and inflammatory markers, and suggest that cytokines secreted by adipose tissue in obese subjects could play a role in increased inflammatory proteins secretion by the liver.