Breakthrough Study Reveals How a Metabolic Compound Could Slow Alzheimer's Progression

A new study has uncovered a molecular pathway that may help combat cognitive decline in Alzheimer's disease. Published in Experimental & Molecular Medicine, the research highlights how a metabolic compound called β-hydroxybutyrate (β-OHB) and its epigenetic effects could protect brain function. Scientists believe this discovery opens fresh avenues for developing treatments that target both energy metabolism and gene regulation in neurons.

The findings suggest that boosting β-OHB levels might restore synaptic health and slow disease progression in patients with Alzheimer's.

The study centres on an enzyme called HMGCS2, which produces β-OHB—a molecule that serves as an alternative energy source for neurons. When HMGCS2 activity increases, it elevates β-OHB levels, triggering a chemical modification on histone proteins known as H3K9bhb. This change enhances the expression of genes critical for synaptic function and neuroprotection.

In experiments, mice with Alzheimer's-like symptoms showed improved cognition after treatments designed to strengthen the HMGCS2/β-OHB/H3K9bhb pathway. The research also found that human neurons treated with β-OHB displayed elevated H3K9bhb levels, reinforcing the idea that metabolic regulation of epigenetics could be a broad strategy for protecting brain health. Alzheimer's disease disrupts this pathway, reducing β-OHB production and impairing H3K9bhb signalling, which contributes to synaptic failure and memory loss.

By March 2026, at least five clinical trials had been launched to test therapies that raise β-OHB levels in Alzheimer's patients. These include studies like NCT04805748 in the USA, which investigates ketone supplementation, alongside early-stage genetic approaches. The trials remain in Phases 1-2, with most focusing on pharmaceutical agents such as ketone esters or precursors.

The researchers propose that measuring β-OHB or H3K9bhb levels in blood or cerebrospinal fluid could help track disease progression or gauge responses to metabolic treatments. They also highlight the potential of developing drugs or gene therapies to enhance HMGCS2 activity in the brain, though such strategies pose technical challenges.

The discovery of the HMGCS2/β-OHB/H3K9bhb pathway provides a scientific foundation for new Alzheimer's therapies. Early clinical trials are now testing whether raising β-OHB levels can improve cognitive function in patients. Further research will determine whether targeting this metabolic-epigenetic link can lead to effective treatments for neurodegenerative diseases.