Abstract

Background and Aim: Angiogenesis and anti-apoptosis play crucial roles in ischemic stroke recovery. The mesenchymal stem cell (MSC) secretome, rich in bioactive molecules, presents a promising therapeutic avenue. However, optimizing the culture conditions to enhance the expression of angiogenic markers remains a challenge. This study examines the effect of hypoxic preconditioning on the expression of vascular endothelial growth factor (VEGF), monocyte chemoattractant protein-1 (MCP-1), matrix metalloproteinase-2 (MMP-2), and microRNA (miRNA-128) in the secretome of umbilical cord-derived MSCs (UC-MSCs) from Macaca fascicularis.

Materials and Methods: UC-MSCs were cultured under normoxic (21% O2) and hypoxic conditions (1%, 3%, and 5% O2) for 48 h. The secretome was isolated, and reverse transcription-quantitative polymerase chain reaction was used to quantify the expression of VEGF, MCP-1, MMP-2, and miRNA-128. Expression levels were normalized to housekeeping genes and analyzed using statistical methods to determine significant differences among groups.

Results: Hypoxic preconditioning significantly upregulated VEGF (1% O2), MCP-1 (5% O2), and miRNA-128 (5% O2) expression compared to normoxic conditions. Conversely, MMP-2 expression was highest in normoxic conditions and downregulated under hypoxia. In addition, miRNA-128 was found to be predominantly secreted into the extracellular space under hypoxic conditions rather than retained within cells.

Conclusion: Hypoxic preconditioning effectively modulates the expression of key angiogenesis and anti-apoptotic markers in UC-MSCs. The study highlights the importance of optimizing oxygen levels to enhance the therapeutic potential of MSCderived secretomes for ischemic stroke treatment. Future research should focus on in vivo validation and clinical translation of these findings.

Keywords: angiogenesis, hypoxic preconditioning, ischemic stroke, mesenchymal stem cells, microRNA-128, secretome.