At the heart of most Alzheimer's research has been a familiar target: amyloid beta, the protein that accumulates into the plaques found in affected brains. Drugs that clear those plaques have now reached the clinic, but results in patients have been modest. A team led by Professor Hilmar Bading, director of the Institute of Neurobiology at Heidelberg University's Interdisciplinary Center for Neurosciences (IZN) in Heidelberg, Germany, has been working from a different angle entirely.
Their research focuses on two proteins found in brain cells: the NMDA receptor, which plays a vital role in communication between neurons and is essential for learning and memory, and TRPM4, a separate channel protein. Individually, these proteins perform normal functions. The problem arises when TRPM4 encounters NMDA receptors outside their usual location within synapses — the junctions between nerve cells. When they meet in the wrong place, they form what the researchers describe as a "death complex": a toxic pairing that sets off a chain of cellular destruction, killing neurons and — in a damaging feedback loop — actually promoting the formation of further amyloid deposits.
In Alzheimer's mice, this NMDAR/TRPM4 death complex was found at dramatically higher levels than in healthy animals. The team then tested a compound called FP802, a small molecule previously developed by Prof. Bading's lab that can precisely block the contact surface between the two proteins, preventing them from combining. In treated mice, the results were notable across multiple measures: cognitive decline was slowed, synapse loss was reduced, dendrites — the branching structures through which neurons communicate — were better preserved, and amyloid plaque formation decreased.
The research was published in the journal Molecular Psychiatry in 2025 and drew wider attention following a Heidelberg University press release in March 2026. Prof. Bading cautions that clinical trials in humans are still some way off, requiring extensive further pharmacological development and safety testing. But the researchers believe they have identified a broadly applicable principle that could prove relevant not only to Alzheimer's but to other neurodegenerative diseases, including ALS (amyotrophic lateral sclerosis, also known as motor neurone disease), in which the same death complex appears to play a role.