A Novel Self-assembling Peptide For Functional Myocardial Infarction Repair

This study investigated the effects of the peptide self-assembed to nanofiber hydrogel scaffolds on three-dimensional(3D)myocardial cell culture,myocardial infarction tissue repairing and bone marrow mesenchymal stem cells(BMSCs)differentiation to cardimyogenic cells.In physical chemistry part,Circular Dichroism(CD)spectrum was used to obtain secondary structure of self-assemble peptide,and Atomic Force Microscope(AFM)to analyze the microstructure of hydrogel nanofiber scaffolds.In the cellular part,using erythrocyte hemolysis to analyze the membrane cracking effect treated by the peptide.The nanofiber scaffolds utilized as the 3D culture materials to insight the growth effect of cardiomyocytes.In the animal test part,the survival ability of myocardial cells with characteristics of c-kit+ in peptide hydrogel scaffolds studied by immunofluorescence methods.Tissue repairing influence of myocardial infarction was analyzed by hematoxylin and eosin staining and immunohistochemical.In inducing cells by peptide part,the effect of BMSCs differentiation to myocardial cells inducing by myocardial cracking buffer cultured in hydrogel scaffolds,and the control release effect of different concentrations of the peptide for myocardial induced factors.The results show this new self-assemble peptide form prioritily ?-sheet structure and form piled nanofiber sacffolds in PBS after 24 hours.The myocardial cells grow well in 3D cell cultures,and mRNA level of Notch 1 was ~5 times higher than 2D cell culture.Myocardial infarction repairing in vitro proved that peptide hydrogel scaffold could alleviate tissue necrosis in myocardial infarction area.After induce BMSCs by myocardial cracking buffer,the cells differentiation to the similar trend of myocardial cells in a short time;The peptide hydrogels have a control release ability to different induced factors.As a new nanofiber scaffold material,self-assembling peptide can be used for 3D cell cultures,cell differentiation and tissue repairing in myocardial infarction,approching a new way for cardiovascular disease and myocardial infarction.This study provides the nanometer biological materials areas in cell and stem cell,tissue repairing,protein molecular control release,and which have market potential application;They have great value in biomedical engineering,regenerative medicine and clinical medicine.