Study On The Preparation,characterization And Skin Repair Promotion Of Ginsenoside Rg3 Thermosensitive Hydrogel

The skin is the largest organ of the human body and the first protective barrier against the external environment.The wound healing process is a complex series of biochemical and cellular phenomena to restore the integrity of the skin and subcutaneous tissue.Good clinical wound management including control of microbial infections,cleaning of the wound environment to keep it free of foreign bodies,and selection of appropriate wound dressings are important in treating various complications that may occur during wound healing.Ginsenoside Rg3 has been shown to have beneficial effects on a variety of skin diseases,and there is currently growing interest in designing and developing hydrogels for biomedical applications,which motivates further development of drug-loaded water for tissue repair and topical delivery gel.Therefore,the purpose of this study was to develop an effective and safe hydrogel(Rg3-Gel)using ginsenoside Rg3 and to evaluate the wound healing potential and therapeutic mechanism of Rg3-Gel.The specific research contents and results are as follows:(1)This subject designed a temperature-sensitive hydrogel system containing Rg3 by using SDS as a gelling agent and co-solvent and combining hyaluronic acid,chitosan and poloxamer matrix for Promoting wound healing research.The optimized Rg3-Gel exists in the form of liquid at room temperature and in the form of semi-solid gel at low and high temperature.When applied locally for treatment,Rg3-Gel also exhibits a good network structure,which can undergo phase transition and swelling/de-swelling with changes in ambient temperature,endows the drug delivery with local spatial and temporal controllability,and exerts its plasticity and biocompatibility.Improve the bioavailability of drugs.Poloxamer-based hydrogel dressings are similar to extracellular matrix,which can provide a moist repair environment for wounds and accelerate wound healing.Furthermore,the loading of Rg3 in the hydrogel partially enhanced the free radical scavenging activity.Meanwhile,in vitro antibacterial experiments also showed that Rg3-Gel could more effectively inhibit the growth of Escherichia coli and Staphylococcus aureus.(2)Ultraviolet UVB radiation can cause skin photodamage.In this study,the intervention of Rg3-Gel could significantly improve the viability of UVB-induced oxidatively damaged Ha Ca T cells,reduce the generation of intracellular ROS,increase the activity of SOD,GSH-Px and HYP levels,and reduce the generation of MDA.Rg3-Gel can promote the activation of Caspase-3 and the production of Bax,while inhibiting the expression of Bcl-2,thereby inhibiting the apoptosis of Ha Ca T cells induced by UVB.In addition,Rg3-Gel can inhibit the activation of AP-1,while inhibiting the expression of MMP9,down-regulating the protein expression of NF-κB p65 and reducing the production of TNF-α and IL-1β,COX-2 and i NOS,suggesting that Rg3-Gel has a significant effect on UVB stress in Ha Ca T cells has apparently potent anti-inflammatory effects.In conclusion,Rg3-Gel treatment effectively protected Ha Cat cells from UV-induced photodamage,and the underlying mechanisms involved the inhibition of oxidative damage and inflammatory responses mediated by NF-κB and AP-1 signaling pathways.(3)By constructing a full-thickness skin thickness wound model on the back of mice and using Rg3-Gel for wound treatment,the wound area of the mice in the Rg3-Gel group was significantly reduced compared with the mice in the control group.Histological analysis showed that at the 16 th day of treatment In the Tian Rg3-Gel group,normal skin tissue morphology was observed,and the skin tissue structure was complete.And ginsenoside Rg3 has high biological activity,so Rg3-Gel can promote collagen deposition,epithelial and new blood vessel formation,and Rg3-Gel also reduces NF-κB,p62,Akt,Erk,p38,JNK proteins and proteins in damaged skin tissue of mice.Its phosphorylation level increases the expression of autophagy proteins LC3,Atg5,and Beclin-1,thus becoming an important material for the preparation of wound dressings.(4)In 16 S rDNA sequencing,Rg3-Gel can increase the number of OTUs of wound flora,improve the richness and diversity of skin wound microbial communities to regulate host immunity,in addition,can also increase Firmicutes and Bacteroidetes The proportion of probiotic bacteria Lactobacillus and Bacteroides effectively restore the skin microbiota,reduce the relative frequency of pathogenic bacteria such as Sphingomonas to prevent infection.From these preliminary evaluations,it can be concluded that Rg3-Gel has excellent potential for application in wound healing drug delivery systems.