Experimental Studies On Temperature-controlled Chitosan Hydrogel Of The Injectable Engineered Myocardial Tissues

lschemic heart disease shows high morbidity and mortality clinically. Currently, heart transplantation is the main successful treatment for endstage heart failure; however, the ability to provide this treatment is limited by the availability of donor hearts. The recent study shows that the transplantation of viable cells improve the ischemic heart function, but injected cell shows low retention and survival, which are not leading to obvious long term therapeutic efficacy.Tissue engineering may provide promising alternatives for the treatment of ischemic heart failure, especially recent study in the injectable biomaterial hydrogel gained serial development, and established the foundation for the advanced development of the injectable engineered myocardial tissues and treatment of ischemic heart failure. Injectable materias, including fibrin glue and Matrigel, were used to treat ischemic heart disease. However, fast degradation in ischemic area influence therapeutic efficacy.Chitosan hydrogel gains temperature-controlled property by mixing polyol sodium glycerophosphate solution and chitosan solution, and shows good property in the biocompatibility of hydrogels, the degradation of hydrogels and the controllable coagulation time. Firstly this study was prepared temperature-controlled chitosan hydrogel by mixing chloridate chitosan and glycerol-2-phosphate (β-GP), which showed the physical stability, good histocompatibility and biodegradation, Therefore, the hydrogel may have potential as the injectable biomaterial scaffold of myocardial tissue engineering. Secondly chitosan hydrogel was directly injected into the infarcted area of rat heart, 4 weeks later, the detection shows that the injection of chitosan hydrogel obviously improved the thick of the left ventricle wall, increased the blood vessel density and viable myocardium , and abated the fibrosis degree compared to the MI group and the PBS group. Finish, chitosan hydrogel mixed with C2C12 were injected into the infarcted area of rat heart, compared with PBS with C2C12. 4 weeks after injection the results showed the injection of chitosan hydrogel with C2C12 cells increased cell transplant retention and survival within the infarct, restored myocardial cell increased the blood vessel density and improved cardiac function. The above-mentioned results showed the temperature-controlled chitosan hydrogel worked as a injectable biomaterial engineering myocardium may have potential prospect to treat ischemic heart disease.The detailed contents are as follows:1. Reparation of hydrogels and the study of biological nature.2. Implantation of injectable chitosan hydrogel on infarcted area of rat heart.3. Implantation of injectable chitosan hydrogel mixed with C2C12 into infarcted area of rat heart.