Gut microbiome's role in Alzheimer's disease confirmed: Study demonstrates transference of cognitive impairments in rats

Groundbreaking research has definitively confirmed the critical role of the gut microbiome in the onset and progression of Alzheimer's disease. Utilizing gut microbiota transplants, an international team of researchers has successfully demonstrated the transference of memory impairments from humans with Alzheimer's to young, healthy rats, shedding light on the specific bacteria in the gut that are directly linked to cognitive decline in Alzheimer's patients.

The study marks a significant turning point in Alzheimer's research, emphasizing the gut microbiome as a promising avenue for the development of novel therapeutic interventions.

According to neuroscientist Yvonne Nolan from University College Cork (UCC) in Ireland, people with Alzheimer's are typically diagnosed at or after the onset of cognitive symptoms, which may be too late, at least for current therapeutic approaches. Understanding the role of gut microbes during the prodromal stage of dementia may open avenues for new therapy development or even individualized intervention.

Prior evidence had suggested a potential association between changes in the gut microbiota and the development of Alzheimer's, but this study is the first to establish a causal link between gut microbiota and the progression of the disease. Neuroscientist Sandrine Thuret from King's College London (KCL) hailed the research as a significant stride forward in comprehending the complex nature of Alzheimer's.

Collaborators from UCC, KCL, and IRCCS Saint John of God Clinical Research Centre of Bresci in Italy conducted a comprehensive investigation into how the gut microbiota of Alzheimer's patients affects brain health and behavior. By conducting transplants of gut microbiota from Alzheimer's patients into young adult rats, the team observed impaired memory behaviors and reduced hippocampal neurogenesis, a process crucial for memory and mood regulation.

Notably, rats that received gut microbiota from Alzheimer's patients displayed more pronounced impairments in hippocampal neurogenesis, correlating with the cognitive test scores of the original donors. Furthermore, changes in the rats' hippocampal metabolome indicated potential contributions to the decreased growth of new neurons in the hippocampus.

While challenges persist in directly measuring hippocampal neurogenesis in living humans, laboratory experiments using human neural stem cells exposed to blood from Alzheimer's patients exhibited decreased neurogenesis, reflecting the findings in rats. The study also identified specific bacterial genera associated with the disease, underlining the need for further research into the intricate relationship between gut microbiota, cognitive impairment, and Alzheimer's disease.

Follow NEWS.am Medicine on Facebook and Twitter