Social interaction plays a critical role in neurogenesis and recovery after stroke

Transl Psychiatry. 2014 Jan 28;4(1):e351. doi: 10.1038/tp.2013.128.

Abstract

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.

Publication types

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

MeSH terms

  • Animals
  • Behavior, Animal / physiology*
  • Brain-Derived Neurotrophic Factor / metabolism
  • Hippocampus / metabolism
  • Infarction, Middle Cerebral Artery / complications
  • Infarction, Middle Cerebral Artery / pathology
  • Infarction, Middle Cerebral Artery / rehabilitation*
  • Interpersonal Relations*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Neurogenesis / physiology*
  • Random Allocation
  • Recovery of Function / physiology
  • Social Isolation*

Substances

  • Brain-Derived Neurotrophic Factor