Enhanced phasic GABA inhibition during the repair phase of stroke: a novel therapeutic target

Takeshi Hiu; Zoya Farzampour; Jeanne T Paz; Eric Hou Jen Wang; Corrine Badgely; Andrew Olson; Kristina D Micheva; Gordon Wang; Robin Lemmens; Kevin V Tran; Yasuhiro Nishiyama; Xibin Liang; Scott A Hamilton; Nancy O'Rourke; Stephen J Smith; John R Huguenard; Tonya M Bliss; Gary K Steinberg

doi:10.1093/brain/awv360

Enhanced phasic GABA inhibition during the repair phase of stroke: a novel therapeutic target

Brain. 2016 Feb;139(Pt 2):468-80. doi: 10.1093/brain/awv360. Epub 2015 Dec 18.

Authors

Takeshi Hiu¹, Zoya Farzampour², Jeanne T Paz³, Eric Hou Jen Wang⁴, Corrine Badgely⁵, Andrew Olson⁶, Kristina D Micheva⁷, Gordon Wang⁷, Robin Lemmens⁸, Kevin V Tran⁴, Yasuhiro Nishiyama⁴, Xibin Liang⁴, Scott A Hamilton⁴, Nancy O'Rourke⁷, Stephen J Smith⁷, John R Huguenard⁵, Tonya M Bliss⁴, Gary K Steinberg⁹

Affiliations

¹ 1 Department of Neurosurgery, Stanford University, Stanford, CA, USA 2 Stanford Stroke Centre, Palo Alto, CA 94304, USA tbliss1@stanford.edu gsteinberg@stanford.edu.
² 3 Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA tbliss1@stanford.edu gsteinberg@stanford.edu.
³ 3 Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA 4 Gladstone Institute of Neurological Disease and University of California, San Francisco San Francisco, CA USA.
⁴ 1 Department of Neurosurgery, Stanford University, Stanford, CA, USA 2 Stanford Stroke Centre, Palo Alto, CA 94304, USA.
⁵ 3 Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA.
⁶ 1 Department of Neurosurgery, Stanford University, Stanford, CA, USA.
⁷ 5 Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA.
⁸ 1 Department of Neurosurgery, Stanford University, Stanford, CA, USA 2 Stanford Stroke Centre, Palo Alto, CA 94304, USA 6 KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology; VIB - Vesalius Research Center University Hospitals Leuven, Department of Neurology, B-3000 Leuven, Belgium.
⁹ 1 Department of Neurosurgery, Stanford University, Stanford, CA, USA 2 Stanford Stroke Centre, Palo Alto, CA 94304, USA 3 Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA tbliss1@stanford.edu gsteinberg@stanford.edu.

Abstract

Ischaemic stroke is the leading cause of severe long-term disability yet lacks drug therapies that promote the repair phase of recovery. This repair phase of stroke occurs days to months after stroke onset and involves brain remapping and plasticity within the peri-infarct zone. Elucidating mechanisms that promote this plasticity is critical for the development of new therapeutics with a broad treatment window. Inhibiting tonic (extrasynaptic) GABA signalling during the repair phase was reported to enhance functional recovery in mice suggesting that GABA plays an important function in modulating brain repair. While tonic GABA appears to suppress brain repair after stroke, less is known about the role of phasic (synaptic) GABA during the repair phase. We observed an increase in postsynaptic phasic GABA signalling in mice within the peri-infarct cortex specific to layer 5; we found increased numbers of α1 receptor subunit-containing GABAergic synapses detected using array tomography, and an associated increased efficacy of spontaneous and miniature inhibitory postsynaptic currents in pyramidal neurons. Furthermore, we demonstrate that enhancing phasic GABA signalling using zolpidem, a Food and Drug Administration (FDA)-approved GABA-positive allosteric modulator, during the repair phase improved behavioural recovery. These data identify potentiation of phasic GABA signalling as a novel therapeutic strategy, indicate zolpidem's potential to improve recovery, and underscore the necessity to distinguish the role of tonic and phasic GABA signalling in stroke recovery.

Keywords: brain repair; phasic GABA; stroke; zolpidem.

Publication types

Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Animals
Drug Delivery Systems* / trends
GABA-A Receptor Agonists / administration & dosage*
Male
Mice
Mice, Inbred C57BL
Neocortex / drug effects
Neocortex / physiology
Neural Inhibition / drug effects
Neural Inhibition / physiology*
Organ Culture Techniques
Pyridines / administration & dosage*
Receptors, GABA-A / physiology*
Recovery of Function / drug effects
Recovery of Function / physiology
Stroke / drug therapy*
Stroke / pathology
Stroke / physiopathology
Zolpidem

Substances

GABA-A Receptor Agonists
Pyridines
Receptors, GABA-A
Zolpidem

Abstract

Publication types

MeSH terms

Substances

Grants and funding