THE POTENTIAL OF STEM CELLS IN THE STUDY AND TREATMENT OF THE CENTRAL NERVOUS SYSTEM

Letter to the Editor

F. Agostini^*

Stem Cell Unit, Centro di Riferimento Oncologico di Aviano (CRO) IRCCS, Aviano, Italy.

*Correspondence to:
Francesco Agostini,
Stem Cell Unit,
Centro di Riferimento Oncologico di Aviano (CRO) IRCCS,
Via F. Gallini 2,
33081 Aviano, Italy.

Received: 18 March, 2025 Accepted: 30 May, 2025

ISSN 2279-5855 print ISSN 2974-6345 online. Copyright © by BIOLIFE 2025 This publication and/or article is for individual use only and may not be further reproduced without written permission from the copyright holder. Unauthorized reproduction may result in financial and other penalties. Disclosure: All authors report no conflicts of interest relevant to this article.

KEYWORDS: Stem cell, differentiation, therapy, central nervous system, multiple sclerosis
 

INTRODUCTION

Stem cells are self-renewal cells that can divide multiple times and produce other identical stem cells (1). Furthermore, these cells undergo differentiation and can transform into specialized cells, such as neurons, skin cells, muscle cells, and blood cells, amongst others. The most widely studied stem cells are embryonic stem cells, which can give rise to all cell types in the body (2). Adult stem cells are located in the bone marrow, skin, and brain and are used to repair damaged tissue, while induced pluripotent stem cells are adult cells reprogrammed in the laboratory (3). Stem cells serve the body’s growth and development and repair damaged tissue and are used in biomedical research and experimental therapies. They play a very interesting and promising role in the study and potential treatment of the central nervous system (CNS) and spinal cord injuries (4). Stem cells are considered promising in the treatment of diseases and injuries of the CNS, brain, and spinal cord, where they can activate molecular and cellular mechanisms.

DISCUSSION

Stem cells are unspecialized cells capable of renewing themselves while maintaining their characteristics and differentiating into specialized cells, such as neurons or glial cells. The spinal cord transmits nerve impulses between the brain and the rest of the body. After injury, damaged neurons are not easily repaired due to their very limited regeneration capacity (5). In these cases, the use of stem cells has generated considerable therapeutic hope.

Embryonic stem cells are highly plastic and are often used in laboratory research, but not without ethical concerns (6). Significant interest in experimental research has been sparked by the use of healthy adult cells reprogrammed to revert to stem cells. In the spinal cord, stem cells aim to replace damaged neurons and oligodendrocytes, reduce inflammation, promote axon regrowth, and recover motor and sensory functions. This research has proven highly promising in animal models and has raised challenges regarding differentiation, safety, and integration mechanisms.

The damaged CNS is difficult to repair because mature neurons do not divide after an injury, and a glial scar forms with reactive astrocytes and the presence of inhibitory molecules such as Nogo-A that block axonal regrowth (7). Stem cells can differentiate into neurons, oligodendrocytes (to remyelinate axons), and astrocytes, and can be useful therapeutic tools, replacing damaged cells. They can elongate axons and dendrites, form functional synapses, and integrate into existing neuronal circuits. Therefore, stem cells may be important for the functional recovery of the CNS.

In addition to replacing nonfunctioning cells, mesenchymal stem cells also act by reducing inflammatory dynamics, inhibiting the immune response, and modifying the glial scar. Stem cells generate various molecules such as brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), and glial cell-line derived neurotrophic factor (GDNF) (8). These proteins promote neuronal survival, increase synaptic plasticity, and stimulate axonal growth. The formation of these molecules involves the Wnt/β-catenin pathway, which is involved in neuronal differentiation; the Norch pathway, which regulates cell proliferation; and the Sonic hedgehog (Shh) pathway, which participates in neural development and regeneration. These molecular pathways regulate the transition between stem cells and nerve cells.

Stem cells can also play a key role in remyelination by activating oligodendrocytes to produce new myelin and reactivate nerve impulses. Multiple sclerosis (MS) is an autoimmune disease of the CNS characterized by demyelination and axonal damage. Stem cells hold great promise in MS research (9). MS is an inflammatory disease in which the immune system attacks myelin and it can affect both the brain and spinal cord, causing motor, sensory, and cognitive deficits. Stem cells are useful in MS by modulating the immune system, which is reset by reducing the autoimmune attack on myelin.

CONCLUSIONS

Stem cells possess two fundamental characteristics: long-term replication and transformation into specialized cells such as neurons, astrocytes, oligodendrocytes, and so on. Treating the CNS with stem cells is one of the most important fields of regenerative medicine, with the goal of using stem cells to replace damaged neurons, repair tissue, and reduce inflammation. The main clinical applications include Parkinson’s disease, spinal cord injury, MS, and amyotrophic lateral sclerosis.

Conflict of interest

The author declares that they have no conflict of interest.

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