Restoring Brain Energy May Reverse Alzheimer’s Disease, Study Finds

UH Research & Education Institute

Alzheimer’s disease has long been considered irreversible, with decades of research focused on slowing its decline rather than restoring brain function. A new study led by the Pieper laboratory of the Brain Health Medicines Center of the Harrington Discovery Institute at University Hospitals, Case Western Reserve University, and the Louis Stokes Cleveland VA Medical Center, however, now challenges that paradigm. By identifying a fundamentally different driver of disease and demonstrating that key features of Alzheimer’s pathology may be reversible, their findings are changing the field’s view of Alzheimer’s and related forms of dementia.

Published in Cell Reports Medicine, the research shows that disruption of normal cellular homeostasis of NAD+, a central molecule in cellular energy metabolism, is not only a major contributor to Alzheimer’s disease, but a potentially tractable and reversible one.  In preclinical models, preserving NAD+ balance prevented disease onset, while restoring NAD+ balance in animals with advanced disease reversed brain pathology and achieved full cognitive recovery. This represents the first demonstration of the ability to reverse disease in any animal model of Alzheimer’s.

A Shift Away from Amyloid-Centric Thinking

Most current Alzheimer’s therapies focus on reducing amyloid-beta plaque accumulation. While these approaches have yielded incremental progress, they have not fundamentally altered disease trajectory. By contrast, this study suggests a different model: that failure of brain energy metabolism may be a central and actionable driver of disease progression.

NAD+ homeostasis is naturally and progressively lost with aging, but the researchers found that this phenomenon is significantly accelerated in the brains of people with Alzheimer’s brains, relative to age-matched healthy brains.  Without sufficient ability to maintain energy, the brain loses its ability to maintain the critical cellular processes necessary for neuronal survival and function.

“Our findings challenge the long-standing assumption that Alzheimer’s disease is irreversible,” said Andrew A. Pieper, MD, PhD, senior author of the study. “We show that disruption of energy homeostasis is not only central to disease progression, but also a mechanism that can be targeted to restore brain health.”

Reversing Alzheimer’s Pathology in Preclinical Models

Using two well-established mouse models of Alzheimer’s, one driven by amyloid pathology and the other by tau, the researchers tested whether restoring NAD+ balance could alter disease progression.

Both models recapitulate key features of Alzheimer’s, including neurodegeneration, neuroinflammation, synaptic dysfunction, and cognitive decline.

The results were striking:

• Preventing loss of brain NAD+ balance protected against disease development.
• Restoring brain NAD+ balance after disease onset reversed major pathological features and achieved complete recovery of cognitive function.

These effects were accompanied by normalization of blood levels of phosphorylated tau 217, a clinically validated biomarker of Alzheimer’s disease in humans.

"It is particularly exciting that we observed recovery even after significant disease progression,” said Dr. Pieper. “This suggests that the brain retains a capacity for energy-dependent self-repair that has not been previously appreciated.”

Targeting Energy Balance, Not Just Protein Aggregation

To restore NAD+ balance, the team used P7C3-A20, a pharmacologic agent discovered and developed in the Pieper laboratory that enables cells to maintain physiological NAD+ levels under stress.

This approach differs from over-the-counter NAD+ precursors, which directly drive NAD+ production and have been shown in animal models to raise NAD+ to potentially harmful levels. Instead, P7C3-A20 supports homeostatic regulation of NAD+, preserving cellular function without exceeding normal biological limits.

Implications for Alzheimer’s and Beyond

Together, these findings point to a new therapeutic strategy: restoring brain energy balance as a means of enabling the brain to protect and repair itself.

The study provides:

• A drug-based approach that reverses disease features in animal models
• A mechanistic framework linking energy metabolism to neurodegeneration
• Candidate biomarkers and molecular targets to guide clinical translation

This work may also help explain why previous therapeutic strategies have had limited success, by targeting downstream consequences of disease rather than its underlying drivers.

Translational Potential and Next Steps

The findings establish a strong foundation for clinical translation.

Next steps include:

• Defining the key molecular pathways underlying NAD+ balance-mediated recovery
• Identifying complementary therapeutic strategies
• Advancing toward carefully designed human clinical trials

“This research opens a new direction for Alzheimer’s therapeutics,” said Dr. Pieper. “If our findings translate to humans, it could change how we approach not only Alzheimer’s disease, but other age-related neurodegenerative conditions as well.”

Early efforts are also underway to explore how similar mechanisms may link traumatic brain injury to Alzheimer’s disease and how these pathways might be therapeutically targeted.

Reframing Alzheimer’s Disease

By demonstrating that restoring cellular energy balance in the brain can reverse key features of Alzheimer’s in preclinical models, this research challenges one of the field’s most entrenched assumptions that Alzheimer’s disease and related forms of neurodegeneration are inherently irreversible.

With Alzheimer’s affecting millions worldwide, approaches that enable the brain to repair itself represent a critical and long-sought goal.

This study brings that possibility closer to reality.