Social interaction plays a critical role in neurogenesis and recovery after stroke.
Stroke survivors often experience social isolation. Social interaction improves quality of life and decreases mortality after stroke. Male mice (20-25 g; C57BL/6N), all initially pair housed, were subjected to middle cerebral artery occlusion (MCAO). Mice were subsequently assigned into one of three housing conditions: (1) Isolated (SI); (2) Paired with their original cage mate who was also subjected to stroke (stroke partner (PH-SP)); or (3) Paired with their original cage mate who underwent sham surgery (healthy partner (PH-HP)). Infarct analysis was performed 72 h after stroke and chronic survival was assessed at day 30. Immediate post-stroke isolation led to a significant increase in infarct size and mortality. Interestingly, mice paired with a healthy partner had significantly lower mortality than mice paired with a stroke partner, despite equivalent infarct damage. To control for changes in infarct size induced by immediate post-stroke isolation, additional cohorts were assessed that remained pair housed for three days after stroke prior to randomization. Levels of brain-derived neurotrophic factor (BDNF) were assessed at 90 days and cell proliferation (in cohorts injected with 5-bromo-2'-deoxyuridine, BrdU) was evaluated at 8 and 90 days after stroke. All mice in the delayed housing protocol had equivalent infarct volumes (SI, PH-HP and PH-SP). Mice paired with a healthy partner showed enhanced behavioral recovery compared with either isolated mice or mice paired with a stroke partner. Behavioral improvements paralleled changes in BDNF levels and neurogenesis. These findings suggest that the social environment has an important role in recovery after ischemic brain injury.
Department of Neuroscience, University of Connecticut Health Center, Farmington, CT, USA.
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Venna
Department of Neuroscience, University of Connecticut Health Center, Farmington, CT, USA.
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Xu
Department of Neuroscience, University of Connecticut Health Center, Farmington, CT, USA.
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Doran
Department of Neuroscience, University of Connecticut Health Center, Farmington, CT, USA.
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Patrizz
1] Department of Neuroscience, University of Connecticut Health Center, Farmington, CT, USA [2] Department of Neurology, University of Connecticut Health Center, Farmington, CT, USA [3] The Stroke Center at Hartford Hospital, Hartford, CT, USA.
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McCullough
D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D019208:Brain-Derived Neurotrophic Factor / Q000378:metabolism; D006624:Hippocampus / Q000378:metabolism; D020244:Infarction, Middle Cerebral Artery / Q000150:complications / Q000473:pathology / Q000534:rehabilitation*; D007398:Interpersonal Relations; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D055495:Neurogenesis / Q000502:physiology*; D011897:Random Allocation; D020127:Recovery of Function / Q000502:physiology; D012934:Social Isolation
D019208:Brain-Derived Neurotrophic Factor