Effects of xuezhikang on proliferation and adhesion capacity of cultured endothelial progenitor cells: An in vitro study

Abstract: BACKGROUND: Endothelial progenitor cells (EPCs) might be useful in the management of coronary artery disease (CAD). OBJECTIVE: The aim of this study was to investigate the effects of xuezhikang, an extract of Chinese red yeast rice, on the proliferation and adhesion capacity of EPCs from the peripheral blood of patients with stable CAD. METHODS: Mononuclear cells from 20 Chinese patients (14 men, 6 women; mean [SD] age, 64.5 [2.8] years [range, 60–69 years]) were isolated using densitygradient centrifugation. After 4 days in culture, the attached cells were treated with different concentrations of xuezhikang (50, 125, 250, and 500 ng/mL; 20 samples/group), atorvastatin (10 ng/mL; n = 20), or phosphate-buffered saline (control, n = 20) for 3 days. Cells that were positive for 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine-labeled acetylated low-density lipoprotein and lectin were defined as EPCs. They were counted by 2 independent investigators in ≥4 randomly selected highpower fields per well. EPCs were then treated and adherent cells were counted by the independent investigators who were blinded to study drug administration. RESULTS: The mean (SD) number of cultured EPCs in the xuezhikang 50-, 125-, 250-, and 500-ng/mL groups (205 [28], 244 [31], 283 [42], and 334 [43] cells, respectively; all, P < 0.001) was significantly increased in a dose-dependent manner compared with the control group (167 [36] cells). The adhesion capacity of the EPCs was significantly greater in the 4 xuezhikang groups (51 [9], 62 [10], 71 [11], and 83 [12] cells; all, P < 0.001) when compared with that of the control group (41 [7] cells). Both the number of EPCs (327 [49] cells) and the number of adhesive EPCs (84 [15] cells) in the atorvastatin group were also significantly increased compared with the control group (both, P < 0.001); however, these increases were not significantly different from those in the xuezhikang 500-ng/mL group. CONCLUSIONS: Xuezhikang was associated with significantly enhanced proliferation and adhesion capacity of EPCs derived from the peripheral blood of these patients with stable CAD. These effects were not significantly different between xuezhikang and atorvastatin. [Copyright &y& Elsevier]