The use of microdialysis to characterize the endocrine production of human subcutaneous adipose tissue in vivo.

OBJECTIVE

Adipose tissue-derived factors represent important players in the metabolic regulations acting both on systemic and local level. However, their local concentrations in human adipose tissue are poorly described.

METHODS

We measured 24-hour profile and post-glucose load concentrations of selected adipokines in the subcutaneous adipose tissue of 17 healthy women by in vivo microdialysis. During 24-hour period, subjects consumed two standardized meals (at 13.00 h and at 19.00 h).

RESULTS

During 24-hour period, fat interleukin-6, interleukin-8/CXCL8, resistin, and hepatocyte growth factor (HGF) exhibited increase/decrease/plateau pattern and peaked at about 14.30 h. Fat leptin exhibited increase/plateau/decrease/increase pattern and reached plateau between 22.00 and 5.30 h. Fat adiponectin exhibited decrease/plateau pattern and reached plateau between 1.00 and 7.00 h. Fat plasminogen activator inhibitor-1 (PAI-1) exhibited decrease/increase pattern with the lowest value at 20.30 h. Oral glucose consumption significantly increased fat adiponectin and resistin levels and decreased fat leptin and PAI-1 levels, respectively.

CONCLUSIONS

The levels of studied adipokines in subcutaneous fat exhibited significant variations during the 24-hour period after microdialysis catheter insertion that were not reflected in the circulation. Concentrations of adiponectin, resistin, leptin and PAI-1 were regulated by oral glucose ingestion from 1 to 3 h after oral glucose load in healthy women.