Regenerative effect of lyophilized dental follicle mesenchymal stem cells and platelet-rich fibrin in skin wounds in geriatric and young rats

The aim of this study was to investigate the regenerative effect of lyophilized dental follicle mesenchymal stem cells (DF-MSCs) combined with rat platelet-rich fibrin (PRF) on geriatric skin wounds. Human DF-MSCs which were isolated from the wisdom teeth of healthy donors and PRF were mixed and incubated in a 37 °C incubator for 1-2 h containing 1 million cells in 150 mg PRF. The mixture was suspended in a freeze-drying solution and then lyophilized. Wounds were created on the back skin of Wistar albino rats using a 6 mm punch. Lyophilized DF-MSCs, PRF, or PRF + DF-MSCs were applied to the wounds of rats. On the 15th day, the wound area was histopathologically evaluated in rats. Blood samples from rats were analyzed for total antioxidant status (TAOS), and inflammatory cytokine levels using ELISA. In both young and geriatric rats treated with lyophilized PRF + DF-MSCs, wound area began to significantly decrease from the 10th day compared to the untreated group (p < 0.05). Histopathological examination revealed that in the lyophilized PRF + DF-MSCs treated groups, epithelial integrity and scarless healing significantly increased compared to the untreated groups (p < 0.05). There were no significant differences in TAOS, total oxidant status (TOS), tumor necrosis factor (TNF), interleukin-6 (IL6), and hydroxyproline levels in serum samples from young rats on the 15th day. In geriatric rats, hydroxyproline (HYPS) levels were increased in the DF-MSC and PRF + DF-MSC groups (p < 0.01), TNF was significantly elevated in PRF geriatric group and IL6 was increased in the PRF group compared to the control group (p = 0.01). Lyophilized PRF + DF-MSCs, which is a shelf-stable and ready-to-use product, hold promise, especially for traumatic wounds in geriatric individuals with longer healing times.