Motor Skill Training Promotes Sensorimotor Recovery and Increases Microtubule-Associated Protein-2 (MAP-2) Immunoreactivity in the Motor Cortex after Intracerebral Hemorrhage in the Rat

Abstract

Motor skill learning may induce behavioral and neurophysiological adaptations after intracerebral hemorrhage (ICH). Learning a new motor skill is associated with dendritic reorganization and requires protein synthesis and expression of MAP-2. The purpose of this study was to evaluate motor performance and expression of MAP-2 in the motor cortex of rats submitted to intracerebral hemorrhage model (ICH) and skill task training (SK) or unskilled training (US) during 4 weeks. The Staircase test was used for behavioral evaluation, and relative optical densities and morphometrical analysis were used to estimate MAP-2 immunoreactivity and parameters of brain tissue in both motor cortices. Results show that skill task training performed with the impaired forelimb was able to increase MAP-2 immunoreactivity in the motor cortex either in sham or in ICH groups in both cortices: ipsilesional [F (5,35) = 14.25 (P < 0.01)] and contralesional hemispheres [F (5,35) = 9.70 (P < 0.01)]. ICH alone also increased MAP-2 immunoreactivity despite the absence of functional gains. Behavioral evaluation revealed that ICH-SK group performed better than ICH and ICH-US animals in the Staircase test. Data suggest that motor skill training induces plastic modifications in both motor cortices, either in physiological or pathological conditions and that skill motor training produces higher brain plasticity and positive functional outcomes than unskilled training after experimental intracerebral hemorrhage.

Targeted Vagus Nerve Stimulation for Rehabilitation After Stroke

“…Intracerebral hemorrhage (ICH) is a common and devastating subtype of stroke with few post-injury treatment options. Evidence from preclinical studies indicates that reorganization of spared circuits supports recovery after ICH, similar to ischemic stroke (Auriat et al, 2010; Liang et al, 2013; Santos et al, 2013). Based on the premise that VNS enhances plasticity, a study evaluated whether VNS paired with rehabilitative training may lead to improved recovery in a model of ICH (Hays et al, 2014a).…”

Enhancing Rehabilitative Therapies with Vagus Nerve Stimulation

“…A recent global epidemiological study indicates that the disability adjusted life years lost to ICH is nearly double that lost to ischemic stroke, highlighting the significant burden of this disease [71]. Like ischemic stroke, plasticity within spared circuitry is believed to support recovery after ICH [72][73][74]. Therefore, VNS paired with rehabilitative training may enhance reorganization within these motor circuits and support recovery.…”

Recovery and Rehabilitation after Intracerebral Hemorrhage

“…One challenge in preclinical research is the use of different ICH-induction methods and different animal species, resulting in inconsistent histological and behavioral profiles. 16,17 In the most common model (collagenase-induced ICH in rodents), peri-and contrahematomal areas undergo neurogenesis, 18,19 dendritic branching, 20 dendritic reorganization, 21 and axonal spouting. 16 Although some of these histological changes have not yet been linked to behavioral change, 16,21 they are unlikely to be epiphenomena, and a more sensitive testing battery to precisely assay recovery may be required.…”

“…Skilled reach training requires the animal to repeatedly reach and grasp edible pellets without compensatory truncal movements. 42 Skilled reaching activity improves with training, 21,43 and some animals also show improvements in skilled walking and spontaneous forelimb use. 44,45 Skilled reach training of the paretic forelimb increases bihemispheric brain-derived neurotrophic factor (BDNF), 44 bihemispheric dendritic reorganization, 21 and ipsilesional and bilateral sensorimotor astrocytic plasticity.…”