Advancing Spinal Cord Injury Treatment through Stem Cell Therapy: A Comprehensive Review of Cell Types, Challenges, and Emerging Technologies in Regenerative Medicine

Recent approaches in regenerative medicine in the fight against neurodegenerative disease

Neurodegenerative diseases arise due to slow and gradual loss of structure and/or function of neurons and glial cells and cause different degrees of loss of cognition abilities and sensation. The little success in developing effective treatments imposes a high and regressive economic impact on society, patients and their families. In recent years, regenerative medicine has provided a great opportunity to research new innovative strategies with strong potential to treatleva these diseases. These effects are due to the ability of suitable cells and biomaterials to regenerate damaged nerves with differentiated cells, creating an appropriate environment for recovering or preserving existing healthy neurons and glial cells from destruction and damage. Ultimately, a better understanding and thus a further investigation of stem cell technology, tissue engineering, gene therapy, and exosomes allows progress towards practical and effective treatments for neurodegenerative diseases. Therefore, in this review, advances currently being developed in regenerative medicine using animal models and human clinical trials in neurological disorders are summarized.

Improved Efficacy of Delayed Treatment with Human Bone Marrow-Derived Stromal Cells Evaluated in Rats with Spinal Cord Injury

The treatment of spinal cord injury (SCI) with uncultivated human bone marrow-derived stromal cells (bmSCs) prepared by negative selection has been proposed to be therapeutically superior to treatment with stem cells that were expanded in vitro. To explore their use in clinical trials, we studied the functional effects of delayed application at 7 days after SCI by testing different doses of bmSCs. Spinal cord contusion injury was induced in adult male Wistar rats at the thoracic level T9. Human bmSCs were prepared by negative selection without expansion in vitro (NeuroCellsTM). Treatment consisted of one 150 µL injection into the cisterna magna containing 0.5 or 2.5 million fresh bmSCs or 2.5 million bmSCs. The recovery of motor functions was evaluated during a surveillance period of six weeks (6 W), during which spinal cords were assessed histologically. Treatment resulted in a significant, dose-dependent therapeutic effect on the recovery of motor performance. The histological analysis revealed a lower degree of axonal degeneration and better survival of neurons and oligodendrocytes in bmSCs treated rats. Our results support delayed intrathecal application of bmSCs prepared by negative selection without expansion in vitro as a treatment of SCI.

An Insight into the Prospects and Drawbacks of Stem Cell Therapy for Spinal Cord Injuries: Ongoing Trials and Future Directions

Spinal cord injury (SCI) is a devastating neurological disorder that has a substantial detrimental impact on a person's quality of life. The estimated global incidence of SCI is 40 to 80 cases per million people and around 90% of cases are traumatic. Various etiologies can be recognized for SCI, and post-traumatic SCI represents the most common of these. Patients worldwide with SCI suffer from a persistent loss of motor and sensory function, which affects every aspect of their personal and social lives. Given the lack of effective treatments, many efforts have been made to seek a cure for this condition. In recent years, thanks to their ability to regenerate tissue and repair lost or damaged cells, much attention has been directed toward the use of stem cells (embryonic, induced pluripotent, mesenchymal, hematopoietic), aimed at restoring the functional integrity of the damaged spinal cord and improving a functional recovery including sensory and motor function. In this paper, we offer an overview of the benefits and drawbacks of stem cell therapy for SCI based on clinical evidence. This report also addresses the characteristics of various stem cell treatments, as well as the field's likely future. Each cell type targets specific pathological characteristics associated with SCI and demonstrates therapeutic effects via cell replacement, nutritional support, scaffolds, and immunomodulation pathways. SCI accompanied by complex pathological processes cannot be resolved by single treatment measures. Stem cells are associated with the adjustment of the expression of neurotrophic factors that help to achieve better nutrition to damaged tissue. Single-cell treatments have been shown in some studies to provide very minor benefits for SCI in multiple preclinical studies and a growing number of clinical trials. However, SCI damage is complex, and many studies are increasingly recognizing a combination approach such as physical therapy, electrical stimulation, or medication therapy to treatment.