Oleic acid enhances the motility of umbilical cord blood derived mesenchymal stem cells through EphB2-dependent F-actin formation.

ABSTRACT

The role of unsaturated fatty acids (UFAs) is essential for determining stem cell functions. Eph/Ephrin interactions are important for regulation of stem cell fate and localization within their niche, which is significant for a wide range of stem cell behavior. Although oleic acid (OA) and Ephrin receptors (Ephs) have critical roles in the maintenance of stem cell functions, interrelation between Ephs and OA has not been explored. Therefore, the present study investigated the effect of OA-pretreated UCB-MSCs in skin wound-healing and underlying mechanism of Eph expression. OA promoted the motility of UCB-MSCs via EphB2 expression. OA-mediated GPR40 activation leads to Gαq-dependent PKCα phosphorylation. In addition, OA-induced phosphorylation of GSK3ß was followed by ß-catenin nuclear translocation in UCB-MSCs. Activation of ß-catenin was blocked by PKC inhibitors, and OA-induced EphB2 expression was suppressed by ß-cateninsiRNA transfection. Of those Rho-GTPases, Rac1 was activated in an EphB2-dependent manner. Accordingly, knocking down EphB2 suppressed F-actin expression. In vivo skin wound-healing assay revealed that OA-treated UCB-MSCs enhanced skin wound repair compared to UCB-MSCs pretreated with EphB2siRNA and OA. In conclusion, we showed that OA enhances UCB-MSC motility through EphB2-dependent F-actin formation involving PKCα/GSK3ß/ß-catenin and Rac1 signaling pathways.