Objective:To investigate the effects of ginsenoside Rg1 (GS-Rg1) on the secretion of exosomes (MSC-Exo) and expression of angiogenesis related microRNAs (miRNAs) in mesenchymal stem cells.Methods:Human umbilical cord blood mesenchymal stem cells (hUCBMSCs) were divided into experimental group and control group. The experimental group was treated with GS-RG1 at a final concentration of 40 mg/L, while the control group was treated with phosphate buffered saline (PBS) at the same volume. Both groups were cultured for 24 h. The morphology of MSC-Exo was observed by transmission electron microscopy; the characteristic surface markers were identified by Western blot; the concentration of MSC-Exo was detected by dicootanobutyric acid protein quantification method, and the expression of 8 miRNAs related to angiogenesis in MSC-Exo was detected by reverse transcription polymerase chain reaction (RT-PCR).Results:After 24 h of incubation, MSC-Exo with a circular membrane vesicle structure was visible. MSC-Exo was positive for the expression of the characteristic surface markers CD9, CD63 and TSG101. After 24 h of intervention, the concentration of MSC-Exo protein were (1.080±0.019)μg/μl and (0.881±0.032)μg/μl in the experimental group and control group, respectively, with statistically significant difference ( P<0.01). The expression of miR-126-3p, miR-21, miR-146a-5p and miR-125b-5p in the GS-Rg1 group were significantly higher than that in the control group, while the expression of miR-16-5p was significantly lower than that in the control group (all P<0.05). Conclusions:GS-Rg1 promotes the secretion of MSC-Exo and enhances the expression of angiogenesis-related miRNAs within Exo to promote angiogenesis.

Objective:To investigate the effects of mesenchymal stem cells-derived exosomes (MSC-Exos) secreted by mesenchymal stem cells (MSCs) induced by astragaloside IV (AS-IV) on the biological function and pyroptosis of human umbilical vein endothelial cells (HUVECs) injured by high glucose.Methods:After human umbilical cord blood mesenchymal stem cells (hUCBMSCs) were intervened with 400 mg/L of AS-IV, exosomes were extracted, and then the morphology and specific markers of exosomes were identified. Human umbilical vein endothelial cells (HUVECs) were cultured in a medium with a glucose concentration of 30 mmol/L to prepare a high glucose-impaired HUVECs model. High glucose-impaired HUVECs were randomly divided into experimental and model groups, with the experimental group intervened with 100 μg/ml of MSC-Exos and the model group intervened with an equal volume of PBS solution, while a blank control group was also set up. Cell counting Kit-8 (CCK-8) cell proliferation assay, adhesion assay, matrigel tube formation assay and scratch assay were used to detect the effects of AS-IV-mediated MSC-Exos on the proliferation, adhesion, tube formation and migrationability of HUVECs; Western blot and real time fluorescence quantitative polymerase chain reaction (qRT-PCR) were used to detect the protein and mRNA expression of scorch death-related molecules, such as Caspase-1, GSDMD (Gasdermin D) and NLRP3 in each group.Results:The proliferation, adhesion number, tube number and migration width of HUVECs cells were significantly lower than those in the blank group ( P<0.05); The expression of Caspase-1, GSDMD, NLRP3 protein and their mRNA increased significantly ( P<0.001); Under the intervention of MSC-Exos mediated by AS-IV, the cell proliferation, adhesion number, tube number and migration width of HUVECs were significantly higher than those in the model group ( P<0.05); The expression of Caspase-1, GSDMD, NLRP3 protein and their mRNA decreased, with statistically significant difference ( P<0.05). Conclusions:AS-IV mediated MSC-Exos can significantly improve the biological function of high glucose-impaired endothelial cells, and its mechanism may be related to anti-pyroptosis.