Endocrine Abstracts

Context: Weight-reducing dietary intervention (DI) promotes an improvement in insulin sensitivity (IS) since early stage of the diet. The diet-induced changes of plasma levels of cytokines and chemokines that are expressed in adipose tissue (adipokines) have been suggested to play a role.

Aim: To examine relationship between the diet-induced changes of IS (assessed using homeostatic model assessment of insulin resistance (HOMA-IR)) and those of plasma adipokines during different time-points of a 6 months multi-phase DI.

Subjects and methods: obese women (BMI 34.8±3.8 kg/m²) were followed during 6 months DI that consisted of a 28 days very-low-calorie-diet (VLCD) and subsequent 5 months weight stabilization phase (WS) including 2 months low-calorie-diet and subsequent 3 months weight maintenance diet. Plasma sampling for analysis of a number of adipokines (serum amyloid A (SAA), haptoglobin, interleukines−6,−8,−1β, tumor-necrosis-factor-α, monocyte-chemoattractant-protein-1, plasminogen-activator-inhibitor-1) using Luminex technology and of relevant hormones and metabolites were performed before the diet and at the the end of each phase.

Results: Body weight (BW) and HOMA-IR decreased during VLCD and during the entire DI (BW: 95.9±12.5 vs 88.5±12.0 (P<0.001) vs 85.3±12.4 (P<0.001), HOMA-IR: 2.9±1.7 vs 1.6±0.8 (P<0.001) vs 1.7±0.9 (P<0.001) respectively). The pre-diet levels of plasma adiponectin correlated positively with HOMA-IR decrease during the early stage of the diet, i.e. during VLCD. The decrease of plasma SAA and haptoglobin levels during VLCD correlated positively with the increase of HOMA-IR during the entire DI. No such correlations were found for other examined adipokines.

Conclusion: Among the adipokines examined, the pre-diet level of plasma adiponectin and the response (decrease) of acute phase proteins (SAA and haptoglobin) during the early stage of the DI appear as determinants of the diet-induced improvement of IS.

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 work was supported, however funding details unavailable.