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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.
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Objective By taking usage of bioinformatics screening methods,this medical research aimed at exploring how the miRNAs in endothelial progenitor cell exosomes relate to the regulation of angiogenesis.Methods miRNAs in endothelial progenitor cells exosomes and angiogenesis-related miRNA was intersected from the existing database to obtain the candidates of miRNA molecules related to angiogenesis in endothelial progenitor exosomes.Results 160 and 50 miRNAs in endothelial progenitor cell candidates were obtained through experimental data analysis and literature searching respectively.600 candidates of angiogenesis-related miRNAs were obtained through literature searching;the top 20 with the highest frequency were selected out.Finally,9 miRNA candidates (miR-126,miR-21,miR-221,miR-92a,miR-199a,miR-210,miR-214,miR-155,miR-146a) that may be highly expressed in endothelial progenitor exosomes and associated with angiogenesis were obtained for the following research.Conclusions Based on data analysis and literature searching,bioinformatics could screen out the target miRNAs for follow-up studies easily and reliably,it is worthy to be widely applied and popularized.
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Objective To prepare a new-type acellular dermal matrix (ADM) and research on its relevant performance,which would provide theoretical evidence for clinical application.Methods Skin of Bama suckling pig was taken as resource of skin,and technologies of physics,chemistry and biology were selected to prepare new-type ADM.To detect the external structure,physical and chemical property as well as biological property of the prepared new-type ADM,hematoxylin-eosin (HE) staining observation,scanning electron microscope observation,amino acid analysis,material porosity and hydrophilicity test,tensile strength and in vitro degradation experiment,cytotoxicity test,and animal experiment have been conducted.Results New-type ADM cells have been thoroughly removed and dermal matrix remains intact with collagen content of 95.55％,connective three-dimensional pore structure,(85.03 ± O.99) ％ of porosity,(24.56 ± 0.57) ° of contact angle implying new-type ADM was hydrophilic substance,(5.48 ± 0.44) Pa of tensile strength implying its moderate level of pulling force,in vitro degradation period reduced to (28.7 ± O.76) h,and ＞75％ relative growth rate (RGR).Cells grew and proliferated on new-type ADM and could be replaced by original tissue after degradation.Conclusions New-type ADM have overcome disadvantages of traditional preparation method in sabotaging dermal matrix structure and incompletely removing cells from matrix,which is qualified with higher level of collagen content and porosity.With improved biological property,greatly reduced inflammation immunoreactions,and accelerated degradation rate,new-type ADM is of higher level of clinical application value.
