Recent advances in the role of excitation-inhibition balance in motor recovery post-stroke

Ioana-Florentina Grigoras; Charlotte J Stagg

doi:10.12703/r/10-58

Recent advances in the role of excitation-inhibition balance in motor recovery post-stroke

Fac Rev. 2021 Jun 23:10:58. doi: 10.12703/r/10-58. eCollection 2021.

Authors

Ioana-Florentina Grigoras¹, Charlotte J Stagg¹

Affiliation

¹ Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford; Medical Research Council Brain Network Dynamics Unit, University of Oxford, Oxford, UK.

Abstract

Stroke affects millions of people worldwide each year, and stroke survivors are often left with motor deficits. Current therapies to improve these functional deficits are limited, making it a priority to better understand the pathophysiology of stroke recovery and find novel adjuvant options. The excitation-inhibition balance undergoes significant changes post-stroke, and the inhibitory neurotransmitter γ-aminobutyric acid (GABA) appears to play an important role in stroke recovery. In this review, we summarise the most recent studies investigating GABAergic inhibition at different stages of stroke. We discuss the proposed role of GABA in counteracting glutamate-mediated excitotoxicity in hyperacute stroke as well as the evidence linking decreased GABAergic inhibition to increased neuronal plasticity in early stroke. Then, we discuss two types of interventions that aim to modulate the excitation-inhibition balance to improve functional outcomes in stroke survivors: non-invasive brain stimulation (NIBS) and pharmacological interventions. Finding the optimal NIBS administration or adjuvant pharmacological therapies would represent an important contribution to the currently scarce therapy options.

Keywords: GABA; MRS; NIBS; TMS; motor recovery; pharmacological intervention; stroke.

Publication types

Review

Grants and funding

CJS holds a Sir Henry Dale Fellowship, funded by the Wellcome Trust and the Royal Society (102584/Z/13/B). IG was funded by a studentship from the Dulverton Trust, Clarendon Fund and St John's College, and University of Oxford.