The gut contains the largest collection of immune cells in the body. New research at the Buck Institute shows that some of those immune cells travel along the brain/gut axis in a mouse model of Alzheimer’s disease (AD) providing a potential new therapeutic pathway for the memory-robbing malady. The research, published in the August29, 2025 issue of Cell Reports, also shows that feeding the mice a high fiber diet reduces AD-related frailty, including tremor.

Some regions of the brain in people with Alzheimer's reorganize more often while at rest than in people without the disease––and in healthy people this frequent reshuffling sometimes predicts who will develop the condition later, according to a new study from the University of Michigan and Columbia University.

Inflammation in the brain is usually seen as harmful in the aging process—it’s thought to contribute to Alzheimer’s and dementia. But a new study in mice suggests that inflammation, led by an immune molecule called STING, might have a role in protecting the aging brain. The findings also have implications for new experimental Alzheimer’s drugs that are designed to block STING.

A new analysis of 15 years of clinical and genomic data from the UK BioBank and 2 other public resources has found that people who had been diagnosed with select gut diseases – such as functional intestinal disorders – also had a higher likelihood of developing Alzheimer’s disease (AD) and Parkinson’s disease (PD). By harnessing these massive databases, the work explores the relationship between gut disruptions and neurodegeneration, incorporating genetics and proteomics in its characterizations. Conditions in the gut can influence brain health and vice versa. Teasing out the intricacies of this connection – especially the relationship between neurodegenerative diseases, such as AD and PD, and digestive disorders – could help scientists identify disease predictors and improve techniques for early detection and treatment. Using data from the UK Biobank, the SAIL databank, and the FinnGen project, Mohammad Shafieinouri and colleagues investigated correlations between 155 diagnoses for nutritional, metabolic, digestive, and endocrine disorders. They used statistical models that examined the connection between the time of diagnosis for gut-brain disorders and the time of AD or PD diagnosis (spanning 1 to 5, 5 to 10, and 10 to 15 years prior to AD or PD). The clinical data featured more than 502,000 people. They also employed linear models from UK BioBank data to generate polygenic risk scores and assess 1,463 known proteomic biomarkers. The genetic data included more than 487,000 people, and the proteomic data included more than 52,000 people. Overall, Shafieinouri et al. found that any co-occurring gut diagnosis contributes to AD or PD risk, corroborating existing work. There was no statistically significant correlation between years between diagnosis and neurodegeneration onset. Within these gut diagnoses, people with non-infective colitis, gastritis, and oesophagitis had a higher rate of developing AD or PD. This relationship also appeared with functional intestinal disorders. The team also developed an interactive resource to see the breakdown between comorbidities and likelihood of AD or PD.