Vagus nerve stimulation as a promising adjunctive treatment for ischemic stroke

The Food and Drug Administration has approved vagus-nerve stimulation (VNS) for the treatment of patients with epilepsy, depression, and headache. By targeting diverse neuroprotective and neuroplasticity pathways, VNS has the potential to be expanded as a treatment for ischemic stroke. VNS has been found to attenuate infarct volume, reduce neurological deficits, and improve memory and cognition in rats with stroke injuries. Some pilot studies with small sample sizes suggested that VNS paired with rehabilitation can be a promising approach to improve limb motor function in chronic-stroke patients. In this review, we first provide an overview of the diverse effects of VNS in the post-stroke condition, followed by a thorough discussion of the potential mechanisms responsible for its neuroprotective and neuroplasticity-enhancing properties. We also outline the clinical applications of the recently emerging non-invasive VNS. Finally, we summarize the advantages and adverse effects of the current VNS applications, as well as the future challenges and directions for the clinical implementation of VNS in ischemic stroke. Although more fundamental and clinical research is still required to fully understand its mechanisms of efficacy, we believe that the frequent and successful clinical use of VNS as a treatment for ischemic stroke is well within reach.