Ye Xiong, Asim Mahmood, Micheal Chopp
Recent evidence has suggested that traumatic brain injuries can be treated effectively using mesenchymal stem cells (MSC). Treatment does not completely reverse the damage caused by a traumatic brain injury but has been shown to have a significant therapeutic effect. An important factor in utilizing MSCs for brain injuries is their ability to generate exosomes. Exosomes are lipid vesicles capable of crossing the blood brain barrier and are heavily involved in cellular communication.They shuttle proteins and genetic information between neighboring and distant cells. Disadvantages seen in the use of therapeutic MSCs seem to be absent with the MSC derived exosomes.
MSC-derived Exosome as a Novel Therapy for TBI
Exosomes have recently gained recognition due to their ability to maintain the same therapeutic benefits as traditional MSC therapy and provide a decrease in safety risks for patients. Exosomes have the ability to promote cellular regeneration without the dangers of uncontrolled replication and can be stored without losing function. Exosomes could become a more effective over the counter treatment option. However, their use in clinical treatment of brain injuries is still in its infancy.
microRNAs in MSC-derived Exosomes as Possible Mediators of Neuroplasticity
miRNA regulate gene expression and “are likely to be involved in most biological processes such as developmental timing and host-pathogen interactions as well as cell differentiation, proliferation, apoptosis and tumorigenesis” suggesting that miRNAs might be involved in stimulating neuroplasticity and healing after injury. Theoretically, exosomes may transfer miRNAs to the neural cells which then promotes recovery and regeneration. An important factor to mention is the significance of an exosome’s internal components (proteins, RNAs, lipids, and DNA) in its efficacy. Exosomes without proteins and genetic materials provide no therapeutic benefit in cellular recovery.