Endocrine Abstracts

Objective: To evaluate the effects of free fatty acids (FFAs) on the regulation of plasma and adipose tissue mRNA adiponectin expression in lean and obese subjects.

Methods: Seven obese men (31.3±1.1 kg/m²) and eight lean men (21.3±0.4 kg/m²) were studied. Subjects received an Intralipid 20% infusion over 180-min with sodium heparin. Blood sampling and abdominal subcutaneous adipose tissue biopsy were taken before and after.

Results: The FFA concentration was increased six fold after Intralipid/heparin infusion in both lean and obese groups. Adipose tissue adiponectin mRNA was significantly reduced by Intralipid/heparin infusion (38.0±7.7 vs 21.1±3.0.0, P<0.05), and plasma level of adiponectin was reduced from 5.72 to 5.37 which, however, was a non-significant reduction (P=0.16). If the two groups were separated, in the lean subjects, adiponectin mRNA was significantly lower after Intralipid/heparin infusion (48.3±12.5 vs 23.2±5.0, P<0.05), whereas there was no difference in plasma adiponectin before and after (5.89±0.6 vs 5.84±0.8, P=0.88). In obese subjects, plasma adiponectin concentration was significantly lower after Intralipid/heparin infusion (5.5±0.8 vs 4.8±0.8, P<0.05), whereas there was no difference in adiponectin mRNA expression (26.0±6.3 vs 18.7±3.1, P=0.24).

Conclusions: Albeit the other data on the effect of FFAs on adiponectin concentrations are not consistent, we could get that FFAs suppress the expression of adiponectin in lean and obese human. The issue of possible FFA-induced regulation of adiponectin warrants further investigations.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.