“For some neuroscientists, new studies have changed the way they think about the brain.
“One of the skeptics at that Alzheimer’s meeting was Sangram Sisodia, a neurobiologist at the University of Chicago. He wasn’t swayed by Dr. Cryan’s talk, but later he decided to put the idea to a simple test.
“It was just on a lark,” said Dr. Sisodia. “We had no idea how it would turn out.”
“He and his colleagues gave antibiotics to mice prone to develop a version of Alzheimer’s disease, in order to kill off much of the gut bacteria in the mice. Later, when the scientists inspected the animals’ brains, they found far fewer of the protein clumps linked to dementia.
“Just a little disruption of the microbiome was enough to produce this effect. Young mice given antibiotics for a week had fewer clumps in their brains when they grew old, too.
“I never imagined it would be such a striking result,” Dr. Sisodia said. “For someone with a background in molecular biology and neuroscience, this is like going into outer space.”
“Following a string of similar experiments, he now suspects that just a few species in the gut — perhaps even one — influence the course of Alzheimer’s disease, perhaps by releasing chemical that alters how immune cells work in the brain.
“He hasn’t found those microbes, let alone that chemical. But “there’s something’s in there,” he said. “And we have to figure out what it is.”
Read Carl Zimmer’s full article at The New York Times: Germs in Your Gut are Talking to Your Brain. Scientists Want to Know What They’re Saying.