Study Of Hydrogels Loaded Plantamajoside Promoting Burn Healing

Burns are one of the most common causes of traumatic tissue damage,resulting in the breakdown of the skin barrier,body defense problems,and other diseases.Delayed healing or non-healing of burn wound is the main source of aggravating exogenous infection.Therefore,promoting burn wound healing can help delay the progression of the disease and improve survival and prognosis.Burn model establishmentThe first part is the establishment of burn model.The research of burn and scald treatment drugs is inseparable from the production of animal scald model,and the quality of scald model directly affects the evaluation and identification of drug efficacy.In the current research,there are many kinds of animal models of burn and scald,most of which are caused by fire,liquid,metal heating or corrosive liquid.However,these methods do not have a constant quantitative standard,so it is difficult to unify the burn time,severity and area.The rat experimental animal model and the experimental conditions we found out have strong controllability,unified standards,accurate implementation of fixed burn area,and the experimental results are true and reliable.We believe that it is a good animal experimental model that can be used for basic research of burn wound repair.After he staining,it was observed under microscope that part of the dermal papillary layer fell off,the collagen fibers in the dermis were destroyed and disordered,and some collagen fibers disappeared;there was "leukocyte infiltration zone" between the necrotic tissue and the surviving tissue;some skin appendages in the deep dermis remained,and the leukocyte infiltration was obvious,which proved that the injury of rats was deep II degree skin scald.In conclusion,he staining results showed that the skin injury of 100 ?for 8s was deep ? degree scald,which could be used for further experimental study.Preparation of injectable CMCS/ alginate-PMS hydrogelHydrogels based on carboxymethyl chitosan(CMCs)have been shown to prevent wound infection,reduce inflammatory cell infiltration,and accelerate collagen deposition.Plantamajoside(PMS)is a kind of natural Chinese herbal medicine with biological activity,which has anti-inflammatory,anti-oxidation and promoting wound healing.n this study,a new hydrogel was prepared by using carboxymethyl chitosan(CMCS)and alginate,which was further applied to burn and scald wound healing after loading PMS.The results showed that PMS may affect the gelation process of hydrogels.When PMS dissolved in ethanol was applied to the hydrogels,some aggregation occurred in CMCs/alginate-PMS hydrogels,and PMS was released by slow dissolution and controlled release.The CMCS/ alginate-PMS hydrogels can be used to further study the healing effect of burn and scald.Study on the effect of CMCS/ alginate-PMS hydrogel on wound healingThe results showed that the CMCS/ alginate-PMS hydrogel has good mechanical properties.However,its effect on deep second degree scald wound in rats is still unclear.Therefore,this study further explored its promoting healing effects at both cellular and animal levels.The cell viability test and scratch wound healing test were used to detect its effect on skin cells,and the healing effect was observed on deep second-degree scald wounds in rats.Our data showed that the hydrogel containing 0.25% PMS significantly improved the viability and migration of L929 cells.CMCS/ alginate-PMS hydrogel can significantly improve the wound healing rate,promote granulation tissue proliferation and re-epithelialization,and accelerate collagen deposition.The effect of CMCs/alginate-PMS hydrogels on promoting healing is significant,but the mechanism of its action remains to be further studied.Study on mechanism of promoting wound healing with CMCS/ alginate-PMS hydrogelCMCS/alginate-PMS hydrogel can significantly increase the expression of VEGF,CD31,?-SMA and collagen protein ?,and reduce the expression of collagen ?.The results of this study further demonstrate the molecular basis of CMCS/ alginate-PMS hydrogel in promoting wound healing.Furthermore,CMCs/alginate-PMS hydrogel could significantly reduce the gene and protein expression of IL-1?,IL-6 and TNF-?,and promote the gene and protein expression of IL-10.To clarify its regulatory mechanism,the gene and protein expressions of IRF1,TNF-? and NF-?B signaling pathways were detected by Western blot and PCR.The results showed that the expressions of IRF1,TNF-? and NF-?B genes and proteins were significantly decreased by the CMCS/alginate-PMS hydrogel.CMCS/ alginate-PMS hydrogels accelerate burn wound healing in rats by reducing inflammatory response and increasing angiogenesis and collagen deposition.The mechanism may be related to the regulation of IRF1,TNF-? and NF-?B signaling pathways.In conclusion,the above research explored and established the deep second-degree burn and scald model in rats,and the preparation of CMCS/ alginate-PMS hydrogel provided a new way for wound healing.The possible mechanisms are as follows:improving hematopoietic function,increasing granulation tissue infiltration and related growth factor secretion,promoting neovascularization and collagen deposition;Inhibition of inflammatory signaling pathway and reduction of secretion of inflammatory pro-inflammatory mediators in inflammatory cells may be related to the regulation of IRF1,TNF-? and NF-?B signaling pathways.