ABSTRACT
Objective:To investigate the effect of astragaloside IV (AS-IV) on the secretion of stromal cell-derived factor-1α (SDF-1α) and CXC chemokine receptor 4 (CXCR4) by high glucose injured human umbilical vein endothelial cells (HUVECs), so as to lay a foundation for further study on AS-IV improving angiogenesis by regulating SDF-1 α/CXCR4 axis of endothelial cells.Methods:HUVECs were isolated and cultured from the umbilical vein of full-term healthy newborns and identified by von Willebrand factor (vWF) combined with 4-diamino-2-phenylindole (DAPI) nuclear staining. The obtained HUVECs was cultured in EGM-2 medium with 30 mmol/L glucose for 120 h to obtain high glucose damaged HUVECs. After intervention with different concentration gradients (25 mg/L, 50 mg/L, 100 mg/L, 200 mg/L, 400 mg/L) AS-IV for 72 hours, the contents of SDF-1α and CXCR4 were detected by enzyme linked immunosorbent assay (ELISA) method to determine the best concentration of AS-IV. The supernatant of damaged HUVECs were collected at 6, 12, 24, 48 and 72 hours after intervention with the best concentration of AS-IV, and the contents of SDF-1α and CXCR4 were detected by ELISA method to determine the best action time of AS-IV. The damaged HUVECs was randomly divided into experimental group and control group, and the blank group was set up at the same time. The experimental group was treated with the best concentration of AS-IV and the best time, the control group and the blank group were treated with the same volume of phosphate buffered saline (PBS) solution, and the contents of SDF-1α and CXCR4 in each group were detected by ELISA method.Results:The vWF factor on the cell membrane was green fluorescence, and the nucleus was blue after DAPI staining. When the fusion image showed green fluorescence, HUVECs were identified by blue fluorescence. The expression of SDF-1α in damaged HUVECs was the best when treated with AS-IV of 100 mg/L for 24 hours (1 642.87 pg/ml), and the expression of CXCR4 in damaged HUVECs was the best when treated with AS-IV of 50 mg/L for 48 hours (8.44 ng/ml). Compared with the control group, the contents of SDF-1α and CXCR4 in the experimental group were significantly increased, and the difference was statistically significant ( P<0.05). While the contents of SDF-1α and CXCR4 in the experiment group were slightly less than those in the blank group and there was no statistically significant difference ( P>0.05). Conclusions:AS-IV can promote the expression of SDF-1α and CXCR4 in HUVECs damaged by high glucose to return to normal physiological level, so as to play the role of vascular repair and neovascularization.
ABSTRACT
Objective The objective is to probe into the effects of astragaloside Ⅳ (AS-Ⅳ) on activity and proliferative function of endothelial progenitor cells (EPCs),which lays a foundation for further study on the effects of AS-Ⅳ on vascular neovascularization mediated by endothelial progenitor cells.Methods The mononuclear cells were isolated by the density gradient centrifugation in umbilical cord blood of full-term healthy infants,and EPCs were obtained by subculture and cell identification when the cells presented spindle shapes.The obtained EPCs were randomly divided into the experimental group and the control group.In the experimental group,EPCs were cultured by AS-Ⅳ with different concentration gradients (25 mg/L,50 mg/L,100 mg/L,200 mg/L and 400 mg/L),while in the control group,they were treated with the same amount of phosphate buffer saline (PBS) solutions.The effects of AS-Ⅳ on the proliferation of endothelial progenitor cells was studied by cell counting kit-8 (CCK-8) cell proliferation experiment,and the activity rate of EPCs cells was measured at the optimum concentration of EPCs proliferation.Results EPCs were successfully obtained after confirming nuclear staining test of CD31 antibody and 4',6-diamidi-no-2-phenylindole (DAPI).Further study showed that AS-Ⅳ can promote the proliferation of EPCs,and its optimal concentration of EPCs proliferation is 100 mg/L.Compared with the normal control group,the activity rate of endothelial progenitor cells after intervention of AS-Ⅳ was 98.7％,higher than 98.12％ in the control group,with significant difference (x2 =49.59,P ＜0.01).Conclusions AS-Ⅳ can enhance the activity of human EPCs and promote their proliferation in vitro.