| Objective:Surgical trauma or burns affect millions of people each year,leaving scars that cause serious physical and psychological harm,and maxillofacial trauma with scars are even worse.There is currently a shortage of ideal treatment for scarless regeneration,which is becoming a hot topic.Pectolinarin is a flavonoid with several wound-healing properties,including anti-inflammatory and antibacterial capabilities,but few study focus on pectolinarin’s role in wound healing.Yes associated transcriptional regulator(YAP)is a key gene that regulates scar formation,and molecular docking tests revealed that pectolinarin can bind to YAP,implying that pectolinarin can promote scarless regeneration.On the other hand,pectolinarin is a water-insoluble molecule that requires a good drug delivery platform for exerting its effect.The PF-127 hydrogel is an amphiphilic polymer with temperature-sensitive characteristics that may be employed as a co-solvent and a good biocompatibility drug delivery platform for wound healing.Therefore,in this study,we hope to develop a thermosensitive PF-127 hydrogel dressing loaded with pectolinarin,evaluate its effect on scar-free regeneration,and reveal the likely mechanism.Methods:1.The slow-release capabilities of a temperature-sensitive hydrogel dressing loaded with pectolinarin were assessed using a UV-vis spectrophotometer(UV)absorbance spectrometer,and the micromorphology was observed using scanning electron microscopy.Calcein-AM/PI staining and cytoskeleton staining were used to examine the cytocompatibility of the dressing,and a hemolysis assay was used to assess the dressing’s hemocompatibility.2.The migratory and proliferation capabilities of vascular endothelial cells were investigated utilizing a scratch test and a Cell Counting Kit-8(CCK-8)assay,respectively.And using Real-time polymerase chain reaction(RT-q PCR)to measure the expression levels of key angiogenesis-related genes,such as von willebrand factor(v WF),vascular endothelial growth factor receptor(VEGFR),angiopoietin-1(ANG-1)and endothelial nitric oxide synthase(e NOS).Reactive oxygen species assays were used to determine the antioxidant activities of pectolinarin.3.To test the dressing’s ability for scarless regeneration in vivo,a rat skin defect model was created.H&E and Masson staining were used to observe collagen arrangement,vascular neovascularization,and skin attachment regeneration in the faulty skin,and immunohistochemistry was used to analyze the expression of key scar genes,like YAP,α-smooth muscle actin(α-SMA)and Engrailed-1(En1)at the tissue level.Results:1.The delivery platform of pectolinarin was successfully created using temperature-sensitive PF-127 hydrogel,which did not alter the micromorphology or temperature-sensitive features.Calcain-AM/PI staining revealed no evident dead cells,and no alterations in cell morphology.The hemolysis test findings revealed a hemolysis rate of less than 5%,implying that the dressings are biocompatible.2.The dressing appeared to promote endothelial cell migration,proliferation,and angiogenesis-related gene expression.When the concentration of pectolinarin was20μg/ml,the best effect of increasing cell proliferation was observed,and it efficiently repaired the cell damage induced by ROS.3.According to the rat skin defect model,loading pectolinarin at 25μg/ml,50μg/ml,and 100μg/ml could improve wound healing.Furthermore,histological research revealed that the concentration of 50μg/ml had the optimum effect,with considerable reduction of scar tissue and neater fiber structure and skin attachment.The expression levels of YAP,α-SMA,and En1 were all down-regulated under the dressing,suggesting that which could be a potential mechanism for scarless wound healing.Conclusion:The PF-127@P hydrogel provide a scarless regeneration approach that is safe,effective,and quick.It’s possible due to the ability of boosting wound angiogenesis and antioxidant effects while suppressing the expression of the scar-related gene YAP. |
