Endocrine Abstracts

Background, objective: Adipose tissue is known to secrete a multitude of bioactive adipokines and it seems that the majority of these adipokines is implicated in the pathogenesis of obesity and associated metabolic diseases. Existing research studies mostly concentrated on one or two adipokines and therefore, comparisons of the involvement of different adipokines in these disorders are difficult. Furthermore, associations of circulating adipokine levels with different fat compounds or lifestyle factors are mostly missing in existing studies. This study aimed to provide a comprehensive overview of the associations of a panel of circulating adipokines (adiponectin, leptin, resistin, chemerin, vaspin) with metabolic parameters and renal function in a well characterized large population-based study.

Methods: Data from 4129 subjects of the Study of Health in Pomerania were analyzed. Residual method was used to investigate the associations of MRI-quantified liver fat content as well as visceral (VAT) and subcutaneous adipose tissue (SAT) with circulating adipokine levels. Furthermore, multivariable regression models were applied to examine the associations of adipokine concentrations with lifestyle factors (smoking, alcohol consumption, physical inactivity), metabolic phenotypes, and renal function.

Results: Independently of other fat compounds, liver fat content, SAT, and VAT were inversely associated with adiponectin. Furthermore, an independent positive association of liver fat content and SAT with chemerin was observed. The strongest independent association was detected between SAT and leptin. Physically inactive subjects had higher chemerin and leptin levels and smoking led to higher chemerin as well as lower adiponectin and leptin concentrations. Alcohol consumption was associated with adiponectin (positive) and resistin (inverse). Obese subjects showed increased chemerin, leptin, and vaspin levels, but decreased adiponectin concentrations. All adipokines were associated with lipid markers, whereas associations with parameters of glucose metabolism were only seen for adiponectin, chemerin, and leptin. An inverse association of similar strength was observed between chemerin, leptin as well as resistin and estimated glomerular filtration rate (beta −0.2, P<0.01).

Conclusion: Our results indicate that the associations between different circulating adipokine levels and metabolic risk factors as well as renal function significantly differ. In general, high adiponectin levels seem to have a protective role whereas increased chemerin, leptin, resistin, or vaspin concentrations seem to be disadvantageous for the investigated alterations. Leptin concentrations play a key role during obesity, whereas for other metabolic disorders adiponectin and chemerin levels seem to be more meaningful. During processes of renal disease circulating chemerin, leptin, and resistin levels might be of similar importance.