Wound Healing-Promoting Effects of Flavonoids from Quercus mongolica via 15-PGDH Inhibition and Collagen Biosynthesis

This study investigated the cytotoxicity, 15-hydroxyprostaglandin dehydrogenase (15-PGDH) inhibitory activity, prostaglandin (PG)E2 release, mRNA expression, collagen biosynthesis, and wound healing activity for evaluating the role of flavonoids obtained from Quercus mongolica bark (QMB-flavonoid) in enhancing wound healing. QMB-flavonoid inhibited 15-PGDH activity in a concentration-dependent manner, with a notable reduction at 7.0 μg/mL, and increased PGE2 release from 1,600 to 2,500 pg/mL between 5.0 and 7.0 μg/mL. Gene expression analysis showed a decrease in 15-PGDH, COX-1, and PGT, whereas MRP4 expression increased. Genes related to cell proliferation, such as KDR, were upregulated, with KDR showing a 5.1-fold increase. At 3.0 µg/mL, QMB-flavonoid promoted collagen synthesis by 142.7% with no cytotoxicity observed in fibroblasts up to that concentration. QMB flavonoids also demonstrated significant wound healing effect, showing a 199.3% growth rate and near-complete wound closure by day 15. The treated group exhibited better tissue regeneration and thinner epidermis than the control group. These results suggest that QMB-flavonoid have potential therapeutic applications in skin regeneration.