Endocrine Abstracts

Introduction: Glitazones’ admisitration has been proved to affect EPCs in peripheral circulation in endothelial function and inflammatory process. The purpose of this study was to further investigate if the administration of pioglitazone in diabetics can modify the number of EPCs in the peripheral blood and alter the inflammatory state and endothelial function of these patients.

Methods: Twenty five diabetic patients were recruited and pioglitazone was administered to all patients for a one-month period. In parallel 10 non-diabetic control subjects were treated with placebo. Blood samples were drawn on admission and after one month of drug’s administration in order to count EPCs and inflammation markers such as CRP, vascular endothelial growth factor (VEGF) and asymmetric dimethylarginine (ADMA) were also measured. Circulating EPCs were defined by the surface markers CD34+ (CD34 expressing cells) and analyzed by flow-cytometry. Moreover the endothelial function was evaluated using the technique of flow mediated dilation (FMD).

Results: In the group of diabetic patients, no significant difference was observed in the number of endothelial progenitor cells before and after the administration of pioglitazone (3.22±1.96 vs 3.55±1.88, P=NS), either in plasma concentrations of CRP (2.998±3.35 vs 1.962±1.57, P=NS), ADMA (0.78±0.51 vs 0.67±0.51, P=NS) or in endothelial function (0.362±0.075 vs 0.38±0.074, P=NS). The plasma concentrations of VEGF in the group of diabetics showed a significant increase after the administration of pioglitazone (128.14±144.85 vs 177.91±126.26, P<0.05). The number of circulating EPCs was compared between the groups of diabetic patients and control patients there was a significant difference (P<0.01).

Conclusions: Based on the existing data, there is no significant difference in the number of circulating EPCs, CRP and ADMA plasma concentrations and endothelial function before and after the administration of pioglitazone. Nevertheless, the administration of pioglitazone seems to increase plasma levels of VEGF playing a possible role in the stimulation of angiogenesis in diabetes.

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.