Gut Health Intervention Shows Promise in Alleviating Alzheimer’s Symptoms in Mice

NOVATO, CA – August 30, 2025, 19:29:17 PDT – A new study from the Buck Institute for Research on Aging suggests a strong connection between gut health and the progression of Alzheimer’s disease (AD). Researchers discovered that supplementing the diet of mice with the pre-biotic fiber inulin led to improvements in AD-related frailty, including a reduction in tremors, and an overall extension of healthspan. The findings, published in Cell Reports, point to a bi-directional dialog pathway between the gut and the brain, offering potential new avenues for therapeutic intervention.

Alzheimer’s disease, a progressive neurodegenerative disorder, currently affects over 6.7 million americans, a number projected to rise dramatically as the population ages.While current treatments focus on managing symptoms, a cure remains elusive. This research highlights the potential of targeting the gut microbiome-the trillions of bacteria and other microorganisms residing in the digestive tract-as a novel approach to mitigating the disease’s impact. The study’s implications extend beyond AD, possibly informing strategies for other age-related neurological conditions where inflammation plays a key role. Researchers are now investigating whether gut changes are a result of brain alterations or a driving force behind the disease itself.

the research team, led by Dr.Dalip Winer, observed that mice genetically predisposed to develop AD exhibited changes in their gut immune systems. Specifically, migrating immune cells were depleted in the gut. Supplementation with inulin, a type of fiber found in foods like chicory root and onions, replenished these cells and reduced chemokine signaling in the brain. Chemokines are signaling molecules that attract immune cells, and elevated levels are often associated with inflammation.

“We found these migrating cells were replenished in the gut and that AD-related frailty, including the tremor trait, was reduced in the animals,” Dr. Winer stated. Inulin‘s beneficial effects are attributed to its production of short-chain fatty acids and other metabolites within the gut, which can then circulate throughout the body. The dietary intervention improved gut health and, consequently, reduced inflammation in the brain.

Interestingly,the high-fiber diet did not consistently reduce amyloid plaques-protein deposits considered a hallmark of AD-in the mice’s brains. However,the researchers found a significant advancement in overall well-being.An assay evaluating 31 aging metrics revealed that the inulin-supplemented diet extended the animals’ healthspan, enhancing their quality of life.

“We did an assay involving 31 metrics of aging in these mice. The diet definitely extended their healthspan, giving the animals a better quality of life,” Dr. Winer added. “this project supports the ‘eat your fruits and vegetables’ advice that is featured in nearly every dietary proposal.”

Researchers hypothesize that age-related factors may trigger inflammation in the brain, prompting the brain to signal the gut immune system for assistance. While this initial response may be protective, a compromised gut can lead to an overgrowth of harmful bacteria, exacerbating inflammation throughout the body.

“In the begining the process is likely protective,but over time the gut becomes compromised setting the stage for more dangerous types of bacteria to flourish which fuels inflammation throughout the body,” Dr. Winer explained.

Dr. Manisha Makhijani, a researcher involved in the study, emphasized the need for further examination into the gut microbiome’s role in neurological disease. “Maybe there is a microbiome that signals an increased risk of neurological disease. Perhaps we’ll be able to identify specific bacteria that set off immune system inflammation. What if we can inhibit the signaling chemokines early versus late in the disease process? Which woudl be protective for the whole system?” she said. “This paper provides so many avenues for further exploration.”