Potential Role of Growth Factors Controlled Release in Achieving Enhanced Neuronal Trans-differentiation from Mesenchymal Stem Cells for Neural Tissue Repair and Regeneration.

With an increase in the incidence of neurodegenerative diseases, a need to replace incapable conventional methods has arisen. To overcome this burden, stem cells therapy has emerged as an efficient treatment option. Endeavours to accomplish this have paved the path to neural regeneration through efficient neuronal transdifferentiation. Despite their potential, the use of stem cells still entails several limitations, such as low differentiation efficiency and difficulties in guiding differentiation. The process of neural differentiation through the stem cells is achieved through the use of chemical inducers or growth factors and their direct introduction reduces their bioavailability in the system. To address these limitations, neural regeneration ventures require growth factors to be effectively implemented on stem cells in order to produce functional neuronal precursor cells. An efficient technique to achieve it is through the delivery of growth factors via microcarriers for their sustained release. It ensures the presence of commensurable concentration even at later stages of neuronal transdifferentiation. Nanofibers and nanoparticles, along with liposomes and such, have been used to implement this. The interaction between such carriers and the growth factors is mainly electrostatic. Such interaction enables them to form a stable assembly through immobilisation of the growth factor either onto their surfaces or within the core of their structures. The rate of sustained release depends upon the release kinetics associated with the polymeric structure employed and its interaction with the encapsulated growth factor. The sustained release ensures that the stem cells immerse under the effect of the growth factors for a prolonged period, ultimately aiding in the formation of cells showing ample characteristics of neuron precursors. This review analyses the various carriers that have been employed for the release of growth factors in an orderly fashion and their constituents, along with the advantages and the limitations they pose in delivering the growth factors for facilitating the process of neuronal transdifferentiation.