Objective: To investigate the effects of granulocyte colony-stimulating factor (G-CSF) on peripheral endothelial progenitor cells (EPC) and atherosclerosis (AS) in cholesterol-fed rabbits.
Methods: Male New Zealand white rabbits were randomly divided into control group, G group (Recombinant Human Granulocyte Colony Stimulating Factor Injection rhG-CSF 50 microg/d), AS group (high cholesterol diet) and G + AS group (rhG-CSF 50 microg/d plus high cholesterol diet, n = 8 per group). Peripheral blood was collected at baseline and at 1, 4, 8 and 12 weeks, total mononuclear cells (MNCs) were isolated from peripheral blood by Ficoll density gradient centrifugation, and then the cells were plated on fibronectin-coated culture dishes. After being cultured for 7 days, EPCs were characterized as adherent cells double positive for DiLDL uptake and lectin binding by direct fluorescent staining under a laser scanning confocal microscope. After being cultured for 3 days, the number of EPC (PE-CD34/FITC-CD133 double-stained positive cells) was quantified by flow cytometric analysis. Serum NO was measured and aortic plaque area analyzed at 12 weeks.
Results: EPC number was low in control and AS groups and EPC number was significantly increased ( approximately 13-fold, P < 0.001) compared to baseline at 1 week in G and G + AS groups and remained at this level throughout the study period in G group while decreased gradually in G + AS group and returned to baseline level at 12 weeks. Aortic atherosclerotic plaque was visible in both AS and G + AS groups, however, the aortic atherosclerotic plaque area was smaller in G + AS group than that of in As group (59.8 mm(2) +/- 26.9 mm(2) vs. 251.5 mm(2) +/- 83.4 mm(2), P < 0.01). Serum NO was similar between AS and G + AS groups and significantly higher than that in control and G groups.
Conclusion: CSF could attenuate atherosclerosis in cholesterol-fed rabbits by increasing circulating EPC.