The research relates to the theory that there is a connection between Alzheimer’s disease and the bacteria that reside in the gut. As reported by Digital Journal, this year 31 international scientists published a paper which put forward the case for the herpes virus and Chlamydia bacteria causing Alzheimer’s disease.
The argument is that viruses or bacteria are responsible for neuroinflammation. This, in turn, leads to plaque formation. With plaque, the common medical consensus is that a protein called amyloid-beta forms sticky “plaques” in the brains of people with Alzheimer’s disease. This leads to destruction of the surrounding neurons and causes memory loss and other cognitive problems.
The new study has been conducted by Professor Robert Moir of Massachusetts General Hospital. The aim was to see if a course of antibiotics had any effect on the build-up of amyloid-beta plaques.
To explore this, the researchers administered a range of antimicrobials to mice. The mice were genetically engineered to develop plaques in their brains. The modified mice were divided into a control group (that did not receive the antibiotics) and a test group (which did receive the antibiotics.)
When the results were reviewed, Science News reports it was found that the bacteria given the antibiotics had a similar numbers of microorganisms to the control group. However, the types of bacteria detected differed and there was a notable reduction in bacterial diversity.
Importantly, the reduction in microbial flora affected the brains of the test mice. These mice had fewer plaques in their brains and the plaque formations were smaller in size. From this it is theorized that bacteria send messages to the brain via alterations to the immune system molecules carried in the blood.
Whether these results apply to people is unknown and further research will be required to test this notion. In addition, while most social media reactions were positive, one scientist, John Peters (@johnthejack) tweeted: “Overselling the microbiome: U of Chicago, Alzheimer’s, antibiotics and gut microbes.”
The new research is published in the journal Scientific Reports. The research paper is titled “Antibiotic-induced perturbations in gut microbial diversity influences neuro-inflammation and amyloidosis in a murine model of Alzheimer’s disease.”
