Researchers at the University of California, Irvine announced on April 23 that they have identified a direct connection between dopamine dysfunction in the entorhinal cortex and memory impairment in Alzheimer’s disease. The findings, published in Nature Neuroscience, reveal a previously unrecognized role for dopamine in cognitive decline associated with Alzheimer’s and suggest new possibilities for treatment using existing drugs such as Levodopa.
The discovery is significant because it addresses why memories fade in Alzheimer’s disease and offers hope for developing therapies that could restore memory function. The study found that reduced dopamine levels disrupt the ability of neurons to respond to stimuli needed for learning, leading to impaired memory formation.
Kei Igarashi, Chancellor’s Fellow and associate professor of anatomy and neurobiology at UC Irvine School of Medicine, led the research team. “We did not initially expect dopamine to be affected in Alzheimer’s disease,” Igarashi said. “However, as the evidence accumulated, it became clear that dopamine dysfunction plays a central role in memory impairment.” Using mouse models with Alzheimer’s-like symptoms, researchers showed that restoring dopamine levels through optogenetic techniques or administering Levodopa improved both neural activity and memory performance.
Alzheimer’s affects tens of millions globally. Current treatments mainly target toxic proteins like amyloid-beta but often fail once neuronal dysfunction sets in. This study provides insight into how early changes within brain circuits contribute to associative memory decline and suggests targeting these mechanisms may slow cognitive deterioration.
UC Irvine is recognized for its high research activity according to its official website and participates within the University of California system according to its official website. The university emphasizes advancing knowledge through research, education, public service with inclusive excellence according to its official website, engages internationally according to its official website, holds accreditation from the Western Association of Schools and Colleges Senior College and University Commission according to its official website, and fields NCAA Division I athletic teams known as the Anteaters according to its official website.
This research was supported by grants from national health organizations as well as international collaborators from Japan’s RIKEN Center for Brain Science participated alongside UC Irvine scientists.