Synthesis and Characterization of Injectable Hydrogels with Varying Collagen⁻Chitosan⁻Thymosin β4 Composition for Myocardial Infarction Therapy.

Thirty percent of global mortalities are caused by cardiovascular disease, and 54% of the aforementioned amount is instigated by ischemic heart disease that triggered myocardial infarction. Myocardial infarction is due to blood flow cessation in certain coronary arteries that causes lack of oxygen (ischemia) and stimulates myocardial necrosis. One of the methods to treat myocardial infarction consists in injecting cells or active biomolecules and biomaterials into heart infarction locations. This study aimed to investigate the characteristics of a collagen⁻chitosan-based hydrogel with variations in its chitosan composition. The prepared hydrogels contained thymosin β4 (Tβ4), a 43-amino acid peptide with angiogenic and cardioprotective properties which can act as a bioactive molecule for the treatment of myocardial infarction. A morphological structure analysis showed that the hydrogels lacked interconnecting pores. All samples were not toxic on the basis of a cytotoxicity test. A histopathological anatomy test showed that the collagen⁻chitosan⁻thymosin β4 hydrogels could stimulate angiogenesis and epicardial heart cell migration, as demonstrated by the evaluation of the number of blood vessels and the infiltration extent of myofibroblasts.