Role of Circular Ribonucleic Acids in the Treatment of Traumatic Brain and Spinal Cord Injury

The causal and pathogenetic factors linked to traumatic brain injury (TBI) and spinal cord injury (SCI) are complex. This complexity is a contributive factor in the minimal improvement outcomes of injured individuals. Several studies have demonstrated the potentiality of stem cells in facilitating neuronal growth and improve outcome in various neurological conditions, including TBI and SCI. However, the efficiency concerning stem cell delivery at injured sites is open to question. Circular ribonucleic acids (circular RNAs) have recently been the focus of attention owing to their disparate functions and features in vivo. Exosomes have close relationship with circular RNAs and might have a significant impact on circular RNA expressions. Herein, we reviewed the specific functions of circular RNAs, exosomes, and stem cells in central nervous system conditions, particularly TBI and SCI, and attempted to show the connection among them. Our analyses showed the role of circular RNAs in brain/spinal cord injuries to be multifaceted, as they can modulate several signaling mechanisms while also acting as sponges for microRNAs and binding to their sites. Additionally, circular RNAs can activate several biological, molecular, and cellular activities in the wake of brain/spinal cord injuries. Thus, both non-pharmacological and pharmacological interventions centered on the regulation of circular RNAs could be promising for TBI and SCI.