Early risk assessment of circulating endothelial progenitor cells and plasma stromal cell-derived factor-1 for nondisabling ischemic cerebrovascular events

BACKGROUND: Endothelial progenitor cells (EPCs) play an important role in ischemic stroke. However, there are few studies on the relationship between EPC and nondisabling ischemic cerebrovascular events. Our aim was to investigate the association of EPCs and SDF-1 (serum stromal cell-derived factor-1) with NICE (nondisabling ischemic cerebrovascular events). METHODS: TIA (transient ischemic attack) and minor stroke patients (153 in total) who had an onset of symptoms within 1 day were consecutively collected. 83 of the patients were categorized into the HR-NICE (high-risk nondisabling ischemic cerebrovascular event) group, and 70 of the patients were in the NHR-NICE (non-high-risk nondisabling ischemic cerebrovascular events) group. Adopted FCM (flow cytometry) was used to measure EPCs, taking double-positive CD34/KDR as EPCs. ELISA was used to measure the concentrations of serum SDF-1 and VEGF (vascular endothelial growth factor). By the sequence of admission time, 15 patients were selected separately from the HR-NICE group and NHR-NICE group, and another 15 healthy volunteers were chosen as the NC (Normal Control) group. The MTT method was used to measure the proliferation of EPCs of peripheral blood in all groups, and the Boyden chamber was used to measure the migration of EPCs. RESULTS: Compared with the NHR-NICE group, the HR-NICE group was older and contained more patients with hypertension and diabetes. Triglyceride, total cholesterol, and low-density lipoprotein in the HR-NICE group were also higher. For factors such as smoking, BMI (body mass index), and HCY (homocysteine), there were no significant differences (P > 0.05). Circulating EPCs, SDF-1, and VEGF in the NHR-NICE group were all higher. According to the multifactor regression analysis, age, hypertension, diabetes, total cholesterol, EPCs, and SDF-1 are independent risk factors for HR-NICE. For EPCs of 48-h isolated cultures, proliferation and migration were observed to be weakened compared with those of the NC group (P < 0.05). EPCs in HR-NICE group had lower proliferation and migration than those in NHR-NICE group (P < 0.01). CONCLUSIONS: For TIA and minor stroke patients, circulating EPCs and serum SDF-1 concentrations can be used to prognose HR-NICE. Factors that lead to high-risk NICE might be relevant to the decrease in proliferation and migration of circulating EPCs.