• A review on Stem cells and injectable hydrogels for heart disease
  • Nazanin Khaki,1,* Yasaman Dalman,2
    1. Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Iran
    2. Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Iran


  • Introduction: Myocardial infarction (MI) occurs after the source of oxygen and nutrients to the cardiac muscle become decreases due to blocked coronary arteries. Heart failure causes fibrotic tissue growth and proliferation in the affected area of cardiac muscle lead to a very limited chance for regeneration because of the inability of the myocardium to self-regenerate. Consequent stiffness of the cardiac muscle after myocardial infarction leads to decreased cardiac output, arrhythmia, and sudden cardiac death. Therefore, myocardial tissue engineering(MTE) approaches with a variety of stem cells, including mesenchymal stem cells, cardiac and cardiosphere derived cells, induced pluripotent stem cells, embryonic stem cells, umbilical cord stem cells, and adipose-derived stem cells, have attracted significant attention as a therapeutic treatment for heart failure.
  • Methods: In this study, the method of a library collection, search in various texts, and authoritative scientific articles have been used.
  • Results: Myocytes are surrounded by an extracellular matrix (ECM) network that is produced by cardiac fibroblasts. The major ECM proteins in the myocardial ECM are collagen type I (approximately 85%, depending on the species) and collagen type III (approximately 11%). Various amounts of simultaneous collagens are responsible for the anisotropic mechanical properties in different regions of the heart but after MI and expression of the Pw1 gene, scar tissue create. For preventing this issue several ways provided that they include a patch-based system with stem cells (SCs) that need a surgical operation and also it can distribute the integrity of the electrical or mechanical signal, another ways are the use of injection routes that including intravenous infusion, intracoronary delivery, and intramyocardial injection. Among these ways intravenous the use of hydrogel for intramyocardial injection is more effectible, because hydrogel protects the cells from host inflammation, and enable functional integration with the injured myocardium furthermore, it can contain Growth factors (GF) like bFGF and VEGF for enhancing angiogenesis, TGF-β for ECM remodeling, IGF-1 for reducing fibrosis and TNF-a for reducing local inflammation attenuation. It is noticeable that the use of each stem call has pros and cons. bone marrow cells are including bone marrow-derived mesenchymal stem cells (MSCs), hematopoietic stem cells, and endothelial progenitor cells. a bone marrow-derived mesenchymal stem cell is multipotent ability to differentiate into multiple mature cardiac cell lineages such as cardiac myocytes, endothelial cells, smooth muscle cells, and cardiac fibroblasts also, MSCs from bone marrow can play a role as pacemaker cells by the expression of the hyperpolarization-activated cyclic nucleotide-gated 2 genes (HCN-2). hematopoietic stem cells can be isolated from blood, bone marrow, and umbilical cord blood and Some studies report the ability of these stem cells to transdifferentiate into cardiomyocytes, but this has not been reproduced by all investigators working in this field. endothelial progenitor cells are very similar to hematopoietic stem cells, they are distinguished by their ability to respond to endothelial cell stimuli such as (VEGF), differentiate to form mature endothelial cells. Other cells are cardiac stem cells that they presenting c-kit, nkx2-5, gata4, flk-1, isl-1 antigens. Cardiac stem cells have higher angiogenic, antiapoptotic activity than other stem cells, high regeneration ability, no immunogenicity, they are adapted to the cardiac microenvironment, can also electromechanically coupled with host cells to allow synchronous contraction between the grafted cells and the host tissue but signification limitation of them are low cells population. embronic stem cells are the cell line with the most effective myogenic capabilities, but teratoma formation and immunogenicity are the major concerns in ESC, ethical concerns, incontrollable differentiation, arrhythmias. another one is insuce stem cells that like ESCs, iPSCs are multipotent and clonogenic. adipose-derived stem cells and umbilical cord stem cells also use in some studies. also, the use of mixed stem cell therapies like cardiochimeras and cardioclusters has been studied. for example, the Cardio Clusters are a 3D mixture of mesenchymal stem cells, cardiac progenitor cells, endothelial progenitor cells, and fibroblasts.
  • Conclusion: One of the major problems in the treatment of cardiovascular diseases is the inability of the myocardium to self-regenerate. Current therapies are unable to restore the heart's function after myocardial infarction. injectable hydrogel combined with stem cells SCs is necessary for optimal and effective myocardial recovery.
  • Keywords: stem cell,hydrogel, regenerative medicine