title: Vagus nerve stimulation during rehabilitative training enhances recovery of forelimb function after ischemic stroke in aged rats.
abstract: Advanced age is associated with a higher incidence of stroke and worse functional outcomes. Vagus nerve stimulation (VNS) paired with rehabilitative training has emerged as a potential method to improve recovery after brain injury but to date has only been evaluated in young rats. Here, we evaluated whether VNS paired with rehabilitative training would improve recovery of forelimb function after ischemic lesion of the motor cortex in rats 18 months of age. Rats were trained to perform the isometric pull task, an automated, quantitative measure of volitional forelimb strength. Once proficient, rats received an ischemic lesion of the motor cortex and underwent rehabilitative training paired with VNS for 6 weeks. VNS paired with rehabilitative training significantly enhances recovery of forelimb function after lesion. Rehabilitative training without VNS results in a 34% ± 19% recovery, whereas VNS paired with rehabilitative training yields a 98% ± 8% recovery of prelesion of forelimb function. VNS does not significantly reduce lesion size. These findings demonstrate that VNS paired with rehabilitative training enhances motor recovery in aged subjects in a model of stroke and may suggest that VNS therapy may effectively translate to elderly stroke patients.
authors.affiliation: Department of Bioengineering, Erik Jonsson School of Engineering and Computer Science, The University of Texas at Dallas, Richardson, TX, USA; Texas Biomedical Device Center, Richardson, TX, USA. Electronic address: seth.hays@utdallas.edu.
authors.forename: Seth A
authors.initials: SA
authors.lastname: Hays
authors.affiliation: Texas Biomedical Device Center, Richardson, TX, USA.
authors.forename: Andrea
authors.initials: A
authors.lastname: Ruiz
authors.affiliation: Brain and Mind Research Institute and Department of Neurology and Pediatrics, Weill Cornell Medical College, New York, NY, USA; Burke Medical Research Institute, White Plains, NY, USA.
authors.forename: Thelma
authors.initials: T
authors.lastname: Bethea
authors.affiliation: Texas Biomedical Device Center, Richardson, TX, USA; School of Behavioral Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA.
authors.forename: Navid
authors.initials: N
authors.lastname: Khodaparast
authors.affiliation: Brain and Mind Research Institute and Department of Neurology and Pediatrics, Weill Cornell Medical College, New York, NY, USA; Burke Medical Research Institute, White Plains, NY, USA.
authors.forename: Jason B
authors.initials: JB
authors.lastname: Carmel
authors.affiliation: Department of Bioengineering, Erik Jonsson School of Engineering and Computer Science, The University of Texas at Dallas, Richardson, TX, USA; Texas Biomedical Device Center, Richardson, TX, USA; School of Behavioral Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA.
authors.forename: Robert L
authors.initials: RL
authors.lastname: Rennaker
authors.affiliation: Texas Biomedical Device Center, Richardson, TX, USA; School of Behavioral Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Kilgard
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D004195:Disease Models, Animal; D004558:Electric Stimulation / Q000379:methods*; D005260:Female; D005552:Forelimb / Q000502:physiology*; D006801:Humans; D009043:Motor Activity / Q000502:physiology; D009044:Motor Cortex / Q000502:physiology; D010805:Physical Conditioning, Animal / Q000502:physiology*; D064797:Physical Conditioning, Human / Q000502:physiology; D011916:Rats, Inbred F344; D020521:Stroke / Q000503:physiopathology*; D000071939:Stroke Rehabilitation / Q000379:methods*; D014630:Vagus Nerve / Q000502:physiology*
keywords: Aging; Elderly; Ischemic stroke; Motor function; Recovery; Rehabilitation; Vagus nerve stimulation