An Italian study published in Nature Communications and coordinated by Marcello D’Amelio, associate professor of human physiology and neurophysiology at Rome’s Bio-Medical Campus University in collaboration with the Fondazione IRCCS Santa Lucia and the National Research Council (CNR) in Rome, reports that the origins of Alzheimer’s disease are linked to the death of neurons in an area linked to mood disorders. Until now researchers had looked for the cause of the disease primarily in the hippocampus, the area of the brain associated with memory, because memory loss is one of the principal symptoms of Alzheimer’s.
The new research has found that this is actually just a domino effect, the memory loss is generated by the breakdown that takes place in the hippocampus when it does not receive sufficient amounts of dopamine. This in turn is due to the degeneration of dopaminergic neurons in the ventral tegmental area. Dopamine is a neurotransmitter that plays a fundamental role in the reward circuitry of the brain, cognition, motivation, drug addiction and several psychiatric disorders. This explains why Alzheimer’s is accompanied by a drop in interest for daily activities, leading to depression; it also indicates that the mood changes associated with Alzheimer’s are not a consequence of its manifestation but an alarm bell on the start of the depressive pathology.
The findings could revolutionize to the researchers for treatments of both Alzheimer’s and Parkinson’s, as it is caused by the degeneration of dopaminergic neurons. Indeed, administering a dopamine precursor or an inhibitor of its degradation to animal models led to the restoration of both memory and motivation.
Ilona Catani Scarlett