Fruit Fly Research Links Alzheimer’s Proteins to Systemic Organ Changes and Sensory Decline

Recent research conducted by Baylor College of Medicine and collaborating institutions has provided new insights into how Alzheimer’s disease impacts the entire body, not just the brain. Using a fruit fly model, scientists explored the effects of Alzheimer’s-associated proteins, specifically Aβ42 and Tau, on various tissues across the organism.

While Alzheimer’s is primarily known as a neurodegenerative disorder characterized by amyloid plaques of the Aβ42 protein and neurofibrillary tangles of Tau, emerging evidence indicates that the disease's influence extends beyond the nervous system. The researchers created an Alzheimer’s Disease Fly Cell Atlas by profiling gene expression in single cells from 219 cell types in the heads and bodies of the fruit flies engineered to express Aβ42 or Tau specifically in neurons. This approach minimizes developmental confounders and highlights effects that manifest in adulthood.

The study revealed that expressing Aβ42 predominantly affected neuronal tissues, especially sensory neurons linked to vision, hearing, and smell. Notably, the decline in olfactory function observed in flies parallels early symptoms of Alzheimer’s in humans. Conversely, Tau expression resulted in broader systemic changes, including altered fat metabolism, impaired digestion, and decreased reproductive capacity, mimicking age-related physiological declines. Disruptions in neuronal connectivity and brain-to-body communication pathways were also evident in animals expressing Tau.

These findings suggest that proteins associated with Alzheimer’s can influence various organ systems, providing a more comprehensive understanding of the disease’s progression. The study paves the way for identifying new biomarkers and potential therapeutic targets by illustrating the systemic nature of Alzheimer’s pathology.

Published in the journal Neuron, this research underscores the importance of looking beyond the brain in Alzheimer’s studies and highlights the utility of the fruit fly model in neurodegenerative disease research. The integrated analysis of brain and body changes offers promising avenues for future interventions aimed at halting or reversing disease-related decline across multiple organ systems.