Gut microbiome and neurosurgery: Implications for treatment

Abstract

Introduction: The aim of this review is to summarize the current understanding of the gut-brain axis (GBA), its impact on neurosurgery, and its implications for future treatment. Background: An abundance of research has established the existence of a collection of pathways between the gut microbiome and the central nervous system (CNS), commonly known as the GBA. Complicating this relationship, the gut microbiome bacterial diversity appears to change with age, antibiotic exposure and a number of external and internal factors. Methods: In this paper, we present the current understanding of the key protective and deleterious roles the gut microbiome plays in the pathogenesis of several common neurosurgical concerns. Results: Specifically, we examine how spinal cord injury, traumatic brain injury and stroke may cause gut microbial dysbiosis. Furthermore, this link appears to be bidirectional as gut dysbiosis contributes to secondary CNS injury in each of these ailment settings. This toxic cycle may be broken, and the future secondary damage rescued by timely, therapeutic, gut microbiome modification. In addition, a robust gut microbiome appears to improve outcomes in brain tumour treatment. There are several primary routes by which microbiome dysbiosis may be ameliorated, including faecal microbiota transplant, oral probiotics, bacteriophages, genetic modification of gut microbiota and vagus nerve stimulation. Conclusion: The GBA represents an important component of patient care in the field of neurosurgery. Future research may illuminate ideal methods of therapeutic microbiome modulation in distinct pathogenic settings.

Transcutaneous auricular vagus nerve stimulation as a potential novel treatment for polycystic ovary syndrome

“…Therefore, focusing on the VN might help restore the homeostasis of the microbiota-gut-brain axis to treat these diseases. Compelling evidence have shown that VNS can ameliorate gut dysbiosis-induced pro-inflammatory effects, and VNS may rescue decreased gut mucosal integrity by upregulating enteric glial cells, reducing systemic proinflammatory cytokines, promoting recovery as well as modulating immune functions 118 , 119 . With regard to the effect of VNS/ta-VNS on the GM profile, there is only the paper by Haney et al and although their results were neutral, the authors concluded that VNS remains a promising experimental and therapeutic modality for manipulating GM communities 120 .…”

The microbiome and neurosurgery

“…explores the connection between secondary spinal cord injury (SCI) and gut dysbiosis, disrupting the SCI healing process. [ 5 ] Gut dysbiosis has been shown to prolong locomotive recovery and increase inflammation, which can reduce the potential for functional recovery as well as possibly curtail the development of molecules such as brain-derived neurotrophic factor that are pivotal for neuroplasticity. [ 6 7 ]…”

“…The secondary effects of TBI after initial stabilization of the patient are disruption of the blood–brain barrier, elevated inflammation within the brain, increased production of reactive oxygen species as well as a dysregulated microbiome because of secondary neurodegeneration seen in TBI. [ 5 8 ]…”