Background: Stem cells are of two types: embryonic and adult stem cells and they act as a
repair system by replenishing body tissue. Stem cells differentiate into different types of cells, such as
neural, hematopoietic, adipose, etc. and are used for the treatment of various conditions like myocardial
infarction, spinal cord injury, Parkinson’s disease and diabetes.
Methods: This article focuses on recent research development that addresses the viability issues of
stem cells. The efficiency of transplanted stem cells reduces due to conditions like hypoxia, inflammation,
nutrient deprivation, immunogenicity, extracellular matrix loss on delivery and mechanical stress.
Results: To increase the viability of stem cells, techniques like scaffolds of stem cells with hydrogel or
alginate, pre-conditioning, different routes of administration and encapsulation, are implemented.
Conclusion: For the protection of stem cells against apoptosis, different pathways, namely Phosphoinositide
3-Kinase (PI3K/AKT), Hypoxia-Inducible Factor (HIF1), Mitogen-Activated Protein Kinases
(MAPK) and Hippo, are discussed.
Discussion: Activation of the PI3K/AKT pathway decreases the concentration of apoptotic factors,
while the HIF pathway protects stem cells against the micro-environment of tissue (hypoxia).