There is increasing evidence of a connection between Alzheimer's disease and gut health. For example, studies have found that people with the condition tend to have more pro-inflammatory or “bad” bacteria and fewer anti-inflammatory or“good” bacteria in the intestinesto have. They also tend to have a less diverse intestinal flora overall.
Chun Chen from Emory University in the US and her colleagues have added to this evidence by showing that mice suffering from Alzheimer's-like disease also have more pro-inflammatory bacteria and fewer anti-inflammatory bacteria in their gut.
The researchers also found that healthy mice housed with the sick mice were more likely to develop the disease themselves, possibly through exposure to their cage mates' unhealthy gut microbes.
To find out whether improving gut health could reduce the risk of developing Alzheimer's, Chen and her colleagues gave mice a prebiotic supplement called R13, which is designed to promote healthy gut flora.
They found that mice treated with R13 had less plaque buildupProtein namens Beta-Amyloidin their intestines. Beta-amyloid accumulates in the brains of people with Alzheimer's disease, forming sticky clumps that damage brain networks. Recent research in mice suggests that this protein can travel from the gut to the brain and cause Alzheimer's symptoms.
R13 recently received approval to be tested in a small clinical trial to help scientists determine whether it helps slow or prevent Alzheimer's disease in people. “It sounds really interesting, but we know from the history of Alzheimer's drug trials that many promising treatments fail,” says Bryce Vissel from the University of Technology Sydney, Australia.
In the meantime, Chen recommends eating a varied diet to promote microbial diversity in the gut. “It has been shown, for example, thatthe Mediterranean diet“slows the development of Alzheimer’s disease, which may be due in part to maintaining the diversity of the gut microbiota,” she says.
Reference: Science Advances,DOI: 10.1126 / sciadv.aba0466
