Dynamic distribution of gut microbiota during Alzheimer's disease progression in a mice model

Alzheimer's disease (AD) is an irreversible neurodegenerative disease that affects more than 44 million people worldwide. The pathogenic mechanisms of AD still remain unclear. Currently, there are numerous studies investigating the microbiota-gut-brain axis in humans and rodents indicated that gut microbiota played a role in neurodegenerative diseases, including AD. However, the underlying relationship between the progress of AD disease and the dynamic distribution of gut microbiota is not well understood. In the present study, APP^swe /PS1^ΔE9 transgenic mice of different ages and sex were employed. After the evaluation of the AD mice model, gut metagenomic sequencing was conducted to reveal gut microbiota, moreover, probiotics intervention was treated in the AD mice. The results showed that (1) AD mice had reduced microbiota richness and a changed gut microbiota composition, and AD mice gut microbiota richness was correlated with cognitive performance. We have also found some potential AD-related microbes, for example, in AD-prone mice, the genus Mucispirillum was strongly associated with immune inflammation. (2) Probiotics intervention improved cognitive performance and changed gut microbiota richness and composition of AD mice. We revealed the dynamics distribution of gut microbiota and the effect of probiotics on AD in a mice model, which provides an important reference for the pathogenesis of AD, intestinal microbial markers associated with AD, and AD probiotic intervention.