Adult Human Neurogenesis in Alzheimer's Disease: Are New Neurons Being still Generated?

Alzheimer's disease is a progressive neurodegenerative disorder that disrupts the brain regions involved in memory and cognitive functions. This impairment ultimately results in severe deficits in memory, learning, reasoning, communication, and the ability to perform daily activities. Our research reveals a statistically significant decrease in the density of neural progenitor cells within the dentate gyrus of the hippocampus and the subventricular zone of the lateral ventricles in patients diagnosed with Alzheimer's disease. This reduction correlates with the disease's progression. As Alzheimer’s disease advances, cognitive functions decline progressively, leading to the identification of five distinct stages of β-amyloid distribution across various brain structures. Early symptoms include short-term memory deficits and learning difficulties, along with cognitive, psychiatric, and neurological disturbances. Given the hippocampus's essential role in these functions, one would expect to see substantial changes in this brain region. Thus, understanding adult neurogenesis is vital in Alzheimer’s disease, particularly since the hippocampus, a primary neurogenic area, is notably impacted in affected individuals.