PPARgamma-agonist rosiglitazone increases number and migratory activity of cultured endothelial progenitor cells.

OBJECTIVE: Endothelial progenitor cells (EPC) are involved in the process of endothelial maintenance and angiogenesis and might be related to endothelial function. EPC function was shown to be impaired in type 2 diabetic patients. Since endothelial dysfunction of type 2 diabetic patients can be ameliorated by treatment with thiazolidinediones we asked whether this treatment might also influence number and function of EPC. METHODS AND
RESULTS: We investigated 10 recently diagnosed type 2 diabetic patients and 10 age and sex matched healthy control subjects. After baseline examination of metabolic parameters and EPC, patients received 4 mg rosiglitazone b.i.d. for 12 weeks. We measured EPC number and migratory activity after 3 and 12 weeks of treatment. Migratory activity of EPCs obtained from type 2 diabetic patients at baseline was 40% lower compared to control (P<0.05). There was no significant difference of EPC number between patients (323+/-19) and controls (358+/-25) at baseline. Treatment of patients with rosiglitazone normalized impaired migratory activity of EPC and increased EPC number (464+/-33, P<0.01). In addition treatment improved glycemic control and insulin sensitivity.
CONCLUSIONS: Twelve-week treatment with rosiglitazone improved EPC number and migratory activity of type 2 diabetic patients. The latter mechanism may contribute to the recently observed improvement of endothelial function by rosiglitazone in type 2 diabetes.