Research advances in the application of vagus nerve electrical stimulation in ischemic stroke

Abstract

Stroke seriously endangers human well-being and brings a severe burden to family and society. Different post-stroke dysfunctions result in an impaired ability to perform activities of daily living. Standard rehabilitative therapies may not meet the requirements for functional improvement after a stroke; thus, alternative approaches need to be proposed. Currently, vagus nerve stimulation (VNS) is clinically applied for the treatment of epilepsy, depression, cluster headache and migraine, while its treatment of various dysfunctions after an ischemic stroke is still in the clinical research stage. Recent studies have confirmed that VNS has neuroprotective effects in animal models of transient and permanent focal cerebral ischemia, and that its combination with rehabilitative training significantly improves upper limb motor dysfunction and dysphagia. In addition, vagus-related anatomical structures and neurotransmitters are closely implicated in memory–cognition enhancement processes, suggesting that VNS is promising as a potential treatment for cognitive dysfunction after an ischemic stroke. In this review, we outline the current status of the application of VNS (invasive and non-invasive) in diverse functional impairments after an ischemic stroke, followed by an in-depth discussion of the underlying mechanisms of its mediated neuroprotective effects. Finally, we summarize the current clinical implementation challenges and adverse events of VNS and put forward some suggestions for its future research direction. Research on VNS for ischemic stroke has reached a critical stage. Determining how to achieve the clinical transformation of this technology safely and effectively is important, and more animal and clinical studies are needed to clarify its therapeutic mechanism.

Analysis of factors influencing the efficacy of vagus nerve stimulation for the treatment of drug-resistant epilepsy in children and prediction model for efficacy evaluation

“…Structural lesion is one of the most common causes of drug-resistant focal epilepsy ( 32 , 33 ). Recent studies have shown that VNS has neuroprotective effects in animal models of transient and permanent focal cerebral ischemia, which may be specifically related to mechanisms such as inhibition of apoptosis, mediation of angiogenesis, and protection of the blood-brain barrier ( 34 ). The protective mechanism of VNS against lesion in the brain may make it more effective against focal epilepsy than the generalized epilepsy.…”

Neuromodulation techniques in poststroke motor impairment recovery: Efficacy, challenges, and future directions

“…Studies have been conducted on the application of VNS as a therapeutic option for several neurological conditions, including poststroke complications, for example, motor deficits, cognitive impairments, and mood disturbances. Emerging evidence supports the efficacy of VNS in facilitating poststroke motor recovery[ 30 ].…”

Gastrointestinal Dysfunction in Stroke

“…Vagus nerve stimulation (VNS) regulates this pathway and promotes an anti-inflammatory phenotype post-stroke; it is approved for use in treatment-refractory epilepsy and has shown promise in the restoration of post-stroke upper limb function. 202,203 In a recent RCT, 108 ischemic patients with upper-limb motor dysfunction were randomly assigned to VNS (or control); 90 days after therapy, a clinically meaningful response was achieved in 47% of VNS patients, compared with 24% of controls, as measured on the Fugl-Meyer Assessment Upper-Extremity score (between-group difference: 24%, 95% CI: 6-41, p ¼ 0.0098). 204 Finally, FMT, or the transfer of intestinal bacteria/other microbes from a healthy donor to a post-stroke patient to restore a healthy microbiota, has been considered.…”