Social Isolation Worsens Stroke Outcomes in Mouse Study
Results suggest interleukin-6 inflammatory response is altered by social isolation
MONDAY, March 30 (HealthDay News) -- Mice housed in isolation are more likely to experience major ischemic damage and die of a stroke than their socially housed cohorts, according to research published online March 23 in the Proceedings of the National Academy of Sciences.
Kate Karelina, of Ohio State University in Columbus, and colleagues housed cohorts of male mice either in social isolation (housed individually) or paired them with an ovariectomized female (socially housed). The researchers induced stroke in the male mice via transient intraluminal middle cerebral artery occlusion, or performed SHAM surgery.
Seven days after stroke, only 40 percent of the isolated mice had survived, compared with 100 percent of the socially housed mice, the investigators found. The isolated mice exhibited increased infarct size, increased edema development and an altered neuroinflammatory response compared with the socially housed mice, in particular down-regulated central interleukin-6 (IL-6) and up-regulated peripheral IL-6. Injection of IL-6 neutralizing antibodies in the socially housed mice eliminated observed ischemic differences between the two groups, the researchers report.
"Taken together, these data support a causal role for IL-6 underlying the increase in ischemic injury associated with social isolation and provide evidence that social modulation of immune function can significantly influence stroke outcome," the authors write.