The Effects Of Ginsenoside Rg1 On Promoting Endothelial Repair And Inhibiting Vascular Restenosis And Underlying Mechanisms

Objective:To investigate the effects of ginsenoside Rg1 on promoting endothelial repair and inhibiting vascular restenosis,and to investigate the underlying mechanisms with microenvironment and calcium-sensing receptors(CaSR).Methods:Rats were operated with carotid artery balloon injury.(1)60 rats were randomly divided into:Sham group,Model group,Rg1 4 mg/kg group,Rg1 8 mg/kg Group and Rg116 mg/kg group,and granulocyte colony stimulating factor(G-CSF,30?g/kg)group as a positive control.After the models were established,the G-CSF group was continuously administered for 7 days,the ginsenoside Rg1 groups were continuously administered for 14days.After 14 days of treatment,the inhibitive effects of ginsenoside Rg1 on intimal hyperplasia were evaluated by histology.Flow cytometry was used to detect CD133~+and VEGFR-2~+labeled endothelial progenitor cells(EPCs)in peripheral blood.Smooth muscle progenitor cells(SMPCs)were detected by CD133 and?-smooth muscle actin(?-SMA)double labeled immunofluorescence.Serum levels of stromal cell-derived factor-1?(SDF-1?),stem cell factor(SCF),soluble fractalkine(sFKN)and vascular endothelial growth factor(VEGF)were detected by enzyme linked immunosorbent assay(ELISA).The protein expressions of the SDF-1?,SCF,fractalkine(FKN),CXCR4,c-kit,CX3CR1,as well as CD31 were detected by immunochemistry.(2)40 rats were randomly divided into:Sham group,Model group,Rg1 16 mg/kg group and Rg1 16 mg/kg+CaSR inhibitor(NPS 2143,4.5 mg/kg)group.After the models were established,the Rg1 16 mg/kg+CaSR inhibitor group was given a CaSR inhibitor NPS 2143 every two days.After 14 days continuous administration,the inhibitive effects of ginsenoside Rg1 on intimal hyperplasia were evaluated by histology.Flow cytometry was used to detect CD133~+and VEGFR-2~+labeled EPCs in peripheral blood.The protein expressions of the CD31,CaSR,JNK and P38 were detected by immunochemistry.SMPCs were detected by CD133 and?-SMA double labeled immunofluorescence.Results:(1)Ginsenoside Rg1 and G-CSF inhibited intimal hyperplasia caused by balloon injury,as evidenced by reducing neointimal area(NIA),neointimal area/media area(NIA/MA),neointimal area/internal elastic area(NIA/IELA)and increasing lumen area(LA).(2)Ginsenoside Rg1 could increase CD133~+and VEGFR-2~+labeled EPCs in peripheral blood.Ginsenoside Rg1 and G-CSF promoted re-endothelialization via increasing protein expression of CD31 in vascular walls.(3)Ginsenoside Rg1 and G-CSF reduced the CD133 and?-SMA labeled SMPCs in injured arteries.(4)Ginsenoside Rg1 and G-CSF reduced serum levels of SDF-1?,SCF and FKN,and they also decreased the protein expressions of the SDF-1?/CXCR4,SCF/c-kit and FKN/CX3CR1 axes in injured arteries.(5)CaSR inhibitor reduced the protective effect of ginsenoside Rg1 on inhibiting intimal hyperplasia,reduced effects of Rg1 on CD133~+and VEGFR-2~+labeled EPCs in peripheral blood and protein expression of CD31 in vascular walls.(6)Ginsenoside Rg1 reduced the protein expressions of CaSR,JNK and P38 in injured arteries.(7)Ginsenoside Rg1decreased the CD133 and?-SMA labeled SMPCs in injured arteries.However,the expression of CaSR was increased by Rg1 in the endothelial layer.Conclusions:(1)Ginsenoside Rg1 had the effect on promoting re-endothelialization and inhibiting intimal hyperplasia.(2)Mechanism of ginsenoside Rg1 was related to re-endothelialization on mobilizing EPCs to the injured arteries.(3)Ginsenoside Rg1 changed the protein expressions of the SDF-1?/CXCR4,SCF/c-kit and FKN/CX3CR1 axes in microenvironment to inhibit the proliferation of SMPCs.(4)...