Astragaloside promotes the secretion of MSC-derived exosomal miR-146a-5p by regulating TRAF6/NF-κB pathway to attenuate inflammation in high glucose-impaired endothelial cells.

Abstract

This study aimed to explore the potential of using mesenchymal stem cell (MSC)-derived exosomes (MSC-Exos) pre-treated with Astragaloside IV (ASIV) to alleviate inflammation in high glucose (HG)-damaged endothelial cells. MSC-Exos were isolated from untreated MSCs and ASIV-pre-treated MSCs, and their characteristics were assessed. The expression of miR-146a-5p in MSC-Exos was determined, and it was found that ASIV treatment enhanced its expression. In order to assess the impact of highly miR-146a-5p-expressing MSC-Exos on HG-injured endothelial cells, we established a model of HG-induced inflammation using human umbilical vein endothelial cells (HUVECs). The study measured cell viability, apoptosis, tube formation, and levels of inflammatory cytokines among the different treatment groups. It was found that transferring MSC-Exos with high miR-146a-5p expression to HG-damaged HUVECs increased cell viability and tube formation ability while reducing the number of apoptotic cells. Additionally, changes in inflammatory factors indicated a reduction in the inflammatory response. Further investigation demonstrated that miR-146a-5p inhibited the expression of TNF receptor associated factor 6 (TRAF6) and phosphorylated NF-κB, which are involved in the inflammatory response. This resulted in the alleviation of inflammation in HG-damaged endothelial cells. In summary, our findings indicate that ASIV treatment stimulated the secretion of MSC-Exos that exhibited increased levels of miR-146a-5p. These exosomes, in turn, regulated the TRAF6/NF-κB pathway. As a result of this modulation, the inflammatory response in HG-damaged endothelial cells was alleviated. These findings offer a fresh approach to addressing vascular complications associated with diabetes, which could lead to novel treatment strategies in the field.