| With the development of society and the aging of population structure,articular cartilage injury caused by high-energy trauma or degeneration caused by aging has become a common and frequent clinical disease.Osteoarticular cartilage has no nutritive blood vessels and lymphatic tissue,and its self-repair ability is very limited after injury.Traumatic orthopedic doctors need accepts every year a large number of complex fractures involving the articular surface,usually we only focus on the bony structure of the reset and neglect of articular cartilage injury,and early articular cartilage injury is usually a hidden,so often the best time to delay treatment,accelerate the cartilage damage,leading to the formation of traumatic osteoarthritis,make limited joint activities,Even eventually lead to joint replacement,seriously affecting the quality of life of patients and getting younger.There are a variety of traditional treatment methods,but all of them have various problems,and the prognosis of the injury is mostly fibrocartilage,with poor biomechanical properties,which can only relieve the symptoms,but can not effectively delay the occurrence of osteoarthritis,and treat the symptoms rather than the root cause.Therefore,how to effectively repair and regenerate damaged or missing articular cartilage is of great research significance,and finding appropriate cartilage repair materials has always been a difficult problem for orthopedic surgeons.In recent years,with the continuous innovation of tissue engineering technology and biomaterial technology,it has been found that the three-dimensional network structure of hydrogel is similar to that of normal articular cartilage.Therefore,hydrogel as a cartilage repair material has attracted extensive interest.At present,a variety of natural or synthetic hydrogel materials(such as polyvinyl alcohol,hydroxyethyl methacrylate,chitosan,hyaluronic acid,etc.)have been applied in the repair of articular cartilage injury,showing certain therapeutic effects.However,most of these hydrogels are characterized by low mechanical strength(such as pressure resistance and strain resistance),fragile deformation,poor biocompatibility and bioactivity,and lack of properties such as stimulating the proliferation of chondrocytes and inducing the differentiation of stem cells,so they are still not satisfactory as artificial cartilage repair materials.This project intends to construct ga-loaded nano-composite hydrogel(n-LWG)as a new cartilage repair material through technological innovation by combining lithium nanocellulose(n-LP)rich in life functional elements with wheat protein(WP)and loading ammonia sugar(GA)at the same time,and explore its potential application value in cartilage repair.Part I: Preparation and related physical and chemical properties of n-LWGIn this topic,we used sol-gel method to prepare the li-lw G/wheat protein complex hydrogel.Firstly,sodium silicate,lithium hydroxide and magnesium hydroxide were used to prepare lithium nanocellosol(n-LP)as the basis.Then,the quantitative alcohol-soluble wheat protein(WP)was mixed with n-LP at different concentrations(0%,10 W %,20 W %),and genipin was added as a crosslinking agent to prepare three kinds of nano-lithium algal soil/wheat protein complex hydrogels(WP,n-LW10 and n-LW20).Finally,the compound hydrogels(WP,n-LWG10 and n-LWG20)were prepared by loading them with glucosamine(GA).The composite hydrogels(WP,n-LW10 and n-LW20)were observed by scanning electron microscopy,and their physical and chemical properties(such as microstructure,water absorption and expansion rate,biomechanical strength,release trend of ammonia sugar,in vitro degradation rate,etc.)were characterized in a series.The results showed that n-LW20 microenvironment constituted by the three-dimensional porous network structure could promote cell adhesion,growth,migration and proliferation,and had good cytocompatibility.Moreover,n-LWG20 containing 20 W % lithium nanocalphysol(n-LP)had better mechanical strength,material viscoelasticity,hydroscopicity,biodegradability and ammonia glycogen release ability than hydrogel WP without lithium nanocalphysol and n-LWG10 with low n-LP concentration,and promoted chondrogenic differentiation of BMSCs.The results were statistically different.Therefore,in subsequent experiments,n-LWG was mainly set as n-LWG20 containing 20 W % nanolith algal soil(n-LP).Part II: Study on the biological properties of aminoglycose-loaded lithium algal soil/wheat protein complex hydrogel(n-LWG).The aminoglycose-loaded lithium algal nano-soil/wheat protein composite hydrogel(n-LWG)not only has a three-dimensional network structure similar to that of articular cartilage,but also has better biocompatibility and mechanical strength.The aminoglycose-loaded lithium algal nano-soil/wheat protein composite hydrogel(n-LWG)also further promotes its cartilage repair ability.In this part,rat articular chondrocytes were isolated and cultured in vitro and co-cultured with materials,and their biocompatibility in vitro was determined by CCK-8 cell proliferation test and Live/Dead staining.In addition,rat articular chondrocytes were isolated and cultured in vitro and co-cultured with materials,and the expression level of chondrogenic genes was quantified by PCR.The morphology of chondrocytes was observed by inverted microscope,and the adhesion rate of chondrocytes on the material surface was measured by cell counting.The morphology and adhesion of chondrocytes on the material were observed by Confocal and SEM.The proliferation rate of chondrocytes was measured by CCK-8 method.The results showed that n-LWG had a higher adhesion rate to chondrocytes in the in vitro experiment by observing cell adhesion and growth on material surface by confocal microscope and SEM,compared with n-LW without amosaccharide loading.The expression of cartilage related genes SOX-9,COL-II and Aggrecan(Agg)was significantly increased by QRT-PCR,and the difference was statistically significant.Therefore,it was concluded that the aminoglycose-loaded lithium nanocalphysol/wheat protein complex hydrogel(n-LWG)could further promote the growth of chondrocytes and accelerate the repair of articular cartilage injury.Part III:Animal Experimental Study on the repair effect of n-LWG on articular cartilage defectsLoading ammonia sugar nanometer lithium algal soil/wheat protein composite hydrogel(n-LWG)the study of articular cartilage defect repair effect in the former two parts based on the conclusion,through the construction of rabbit knee joint cartilage defect model,we will be the material into the rabbit knee joint cartilage defect,and materials of 4,8,12 weeks after surgery,bone defect area is generally observed,Micro-CT scanning,H&E Staining,Safarin O/fast green Staining,and histological observation.To investigate the repair effect of aminoglycose-loaded lithium algal soil/wheat protein complex hydrogel(n-LWG)on cartilage defects in vivo.The results showed that,compared with the control group and n-LW without aminoglycose,n-LWG group had more new cartilage around cartilage injury after implantation.Both HE staining images and ferro red-solid green staining images showed that the surrounding new tissue and chondrocytes were more mature,and n-LWG had an excellent effect on promoting cartilage defect repair.Therefore,it can be concluded that ammonia-loaded lithium nanocellosol/wheat protein composite hydrogel(n-LWG)also shows excellent cartilage repair promoting ability in vivo experiments,and has good biomechanical properties,histocompatibility and economy,and is expected to become a reliable commercial cartilage repair product. |
PDF Full Text Request