Combining robotic training and inactivation of the healthy hemisphere restores pre-stroke motor patterns in mice
Abstract
Focal cortical stroke often leads to persistent motor deficits, prompting the need for more effective interventions. The efficacy of rehabilitation can be increased by 'plasticity-stimulating' treatments that enhance experience-dependent modifications in spared areas. Transcallosal pathways represent a promising therapeutic target, but their role in post-stroke recovery remains controversial. Here, we demonstrate that the contralesional cortex exerts an enhanced interhemispheric inhibition over the perilesional tissue after focal cortical stroke in mouse forelimb motor cortex. Accordingly, we designed a rehabilitation protocol combining intensive, repeatable exercises on a robotic platform with reversible inactivation of the contralesional cortex. This treatment promoted recovery in general motor tests and in manual dexterity with remarkable restoration of pre-lesion movement patterns, evaluated by kinematic analysis. Recovery was accompanied by a reduction of transcallosal inhibition and 'plasticity brakes' over the perilesional tissue. Our data support the use of combinatorial clinical therapies exploiting robotic devices and modulation of interhemispheric connectivity.
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Funding
Fondazione Pisa (158/2011)
- Matteo Caleo
Regione Toscana
- Silvestro Micera
- Matteo Caleo
European Union's Horizon 2020 Research and Innovation Program (720270 (HBP SGA1))
- Silvestro Micera
- Matteo Caleo
ERC Advanced Grant 2015 (692943)
- Matteo Caleo
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All procedures were performed in compliance with the EU Council Directive 2010/63/EU on the protection of animals used for scientific purposes, and approved by the Italian Ministry of Health, protocol number DGSAF0015924-16/06/2015.
Copyright
© 2017, Spalletti et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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