Schematic showing how stroke alters gut microbiota, which primes the immune system to exert further damageARTHUR LIESZScientists are finding increasing evidence that the stomach and the brain are linked via microbes and the immune system. Researchers from the Ludwig Maximilian University of Munich in Germany have found that inducing strokes in mice altered the animals’ gut microbiota, triggering an immune response that traveled back to the brain and worsened the severity of the lesions. When the researchers transplanted fecal bacteria from healthy mice into germ-free rodents that had suffered strokes, the latter animals made a better recovery than mice that didn’t receive the healthy bacteria, the researchers reported this week (July 12) in The Journal of Neuroscience.
“It’s a very nice study,” neuroscientist Josef Anrather of Weill Cornell Medical College in New York City, who was not involved in the research, told The Scientist. The authors show that if the stroke is severe enough, it affects the gut microbiota, which then feeds back to the brain, Anrather said. “There are some implications for extending [the findings] to the clinic for stroke” in humans, he added.
Research has shown that ischemic strokes produce an inflammatory response in the brain, which activates lymphocytes—particularly T cells. Depending on their fate, these T cells can help or worsen the brain’s recovery. Accumulating evidence now suggests that microbes in the gut can influence immune activity in the brain via the so-called “gut-brain axis.” Anrather and colleagues published ...
