Fish Skin Collagen-Chitosan-Pectin Scaffold Development And Application On Human Umbilical Cord Mesenchymal Stem Cell Culture And Skin Repair

Biopolymer scaffold,one of the most common 3D culture materials,is able to provide cells with more growth space and better communication environment.Based on how to enhance the mechanical strength of collagen-like scaffolds,we innovatively proposed to prepare salmon skin collagen-chitosan-pectin scaffold to provide a better microenvironment for 3D culture.At the same time,explored the characteristics of hUC-MSCs under the 3D culture provided by this scaffold,and the repair effect of exosomes derived from hUC-MSCs on the subacute aging of mouse skin caused by D-galactose.1、Established the method of fish skin collagen-chitosan-pectin scaffoldFish skin collagen was obtained by enzymatic extraction,salting out,dialysis and lyophilization from salmon skin.The collagen content of fish skin collagen was about92%,and the content of type I collagen in fish skin collagen was more than 90%.And the three-dimensional structure of fish skin collagen was complete.In this experiment,EDC/NHS crosslinking was used to obtain scaffolds with optimal morphology and cell’s adhesion by adjusting the crosslinking concentration and the percentage of fish skin collagen,chitosan and pectin.The appearance of the scaffold is milky white,soft,elastic,can be restored to its original state after rehydration with good flexibility.The scaffold has good water absorption and water retention capacity,and the pore size is between 30 μm and 260 μm.2、Fish skin collagen-chitosan-pectin scaffold have good cytocompatibilityCCK-8 and Calcein/PI staining results showed that the scaffold is noncytotoxic,and cells were allowed to adhere and grow on the scaffold.3 、 The characteristics of hUC-MSCs can be enhanced by Fish skin Collagen-chitosan-pectin scaffold cultureELISA results showed that the secretion of cytokines VEGF,b FGF and TGF-β of hUC-MSCs in 3D culture was significantly elevated than that in 2D culture;RT-q PCR results showed that the expression of stemness related genes Sox2,Oct4 and Nanog of hUC-MSCs in 3D culture were significantly elevated than those in 2D culture,indicating that hUC-MSCs in 3D culture had stronger stemness.4、The repair effect of hUC-MSCs-Exo on skin aging can be enhanced by Fish skin Collagen-chitosan-pectin scaffold cultureC57BL6/J mice were divided into groups to establish a subacute skin aging model by D-galactose.Results showed that the ability of hUC-MSCs-3D-Exo significantly promoted skin cell proliferation,collagen production,increase SOD activity in the skin and reduces the expression of the skin aging marker protein P16 was stronger than that of hUC-MSCs-2D-Exo,indicating that hUC-MSCs-3D-Exo treatment has a better effect on skin aging repair.