In addition to memory problems, Alzheimer’s disease is characterized by progressive disorders of language, writing, movement, mood and sleep. Currently, the diagnosis is established from standardized tests and reinforced by brain imaging and the evolution of the patient. But this technique could soon change: researchers at Columbia University in New York, United States, have located the precise starting point of the disease in the brain.
The study in question, published by the scientific journal Nature Neuroscience focused on the follow-up of 96 seniors. After three and a half years, Alzheimer’s disease was diagnosed in 12 of the participants. By comparing the functional MRI images of patients at the start of the study and those of healthy seniors, the study authors observed a significant drop in activity in the lateral entorhinal cortex.
Two implicated proteins
As the disease progressed, they also noticed that it spread from neuron to neuron, progressively affecting several areas of the brain. Another observation: the researchers proved that, in mice, the simultaneous presence and large quantity of two proteins, the beta-amyloid peptide and the tau protein, would be the cause of the dysfunction of the neurons of the lateral entorhinal cortex. Results to be verified in human patients.
The number of people affected by Alzheimer’s disease should reach two million in France in 2020, according to figures from the national institute of health (Inserm). “It is therefore a major medical, scientific, social and economic issue in all developed countries where life expectancy has increased steadily for a century,” say the Inserm researchers.
