CLEVELAND, December 22, 2023 — For the first time, scientists are suggesting Alzheimer’s disease isn’t necessarily a life sentence. A new study reveals that restoring the brain’s energy balance may not just slow the disease—but actually reverse it, offering a glimmer of hope in a field long dominated by discouraging outcomes.
A Century-Old Assumption Challenged
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The research suggests that cognitive decline from Alzheimer’s may be reversible, a radical departure from the prevailing view.
- For over a century, Alzheimer’s has been considered a progressive and irreversible condition.
- Researchers pinpointed a critical energy imbalance—specifically, declining levels of NAD+—as a key driver of the disease.
- In animal models, restoring NAD+ levels not only prevented Alzheimer’s but reversed cognitive damage.
- The findings open the door to potential new therapies focused on restoring brain energy, rather than just slowing decline.
For more than 100 years, Alzheimer’s disease (AD) has been widely viewed as a condition that cannot be undone. This belief has shaped scientific efforts, focusing on prevention or slowing progression rather than restoring lost brain function. Despite decades of research and billions of dollars invested, no drug trial has ever been designed with the primary goal of reversing the disease and recovering cognitive abilities.
Targeting Brain Energy Failure
That long-held assumption is now being challenged by researchers from University Hospitals, Case Western Reserve University, and the Louis Stokes Cleveland VA Medical Center. Their work sought to answer a fundamental question: can brains already damaged by advanced Alzheimer’s recover?
The research, led by Kalyani Chaubey, PhD, of the Pieper Laboratory and published in Cell Reports Medicine, identified a key biological failure at the center of the disease. The team found that the brain’s inability to maintain normal levels of a vital cellular energy molecule called NAD+ plays a major role in driving Alzheimer’s. Maintaining proper NAD+ balance not only prevented the disease but also reversed it in experimental models.
NAD+ levels naturally decline throughout the body, including the brain, with age. When NAD+ drops too low, cells lose the ability to carry out essential processes. Researchers discovered this decline is far more severe in the brains of people with Alzheimer’s, a pattern also observed in mouse models of the disease.
Modeling Alzheimer’s in the Lab
Scientists study Alzheimer’s using genetically engineered mice that carry mutations known to cause the disease in humans. In this study, researchers used two such models: one with mutations affecting amyloid processing, and another with a mutation in the tau protein.
Amyloid and tau abnormalities are among the earliest and most significant features of Alzheimer’s. In both mouse models, these mutations led to widespread brain damage mirroring the human disease, including breakdown of the blood-brain barrier, nerve fiber damage, chronic inflammation, reduced neuron formation, weakened communication between brain cells, and extensive oxidative damage. The mice also developed severe memory and cognitive problems.
Reversing Alzheimer’s Damage
After confirming the sharp drop in NAD+ levels in both human and mouse Alzheimer’s brains, the team explored whether maintaining NAD+ balance could prevent the disease and whether restoring it could reverse existing damage. This approach built on earlier work demonstrating that restoring NAD+ balance led to recovery after severe traumatic brain injury.
In the current study, researchers used a compound called P7C3-A20, developed in the Pieper laboratory, to restore NAD+ balance.
Striking Results: Full Cognitive Recovery
The results were striking. Preserving NAD+ balance protected mice from developing Alzheimer’s. Even more surprising, restoring NAD+ balance in mice with advanced disease allowed the brain to repair major pathological damage caused by the genetic mutations.
Both mouse models showed complete recovery of cognitive function, reflected in blood tests showing normalized levels of phosphorylated tau 217, a recently approved clinical biomarker for Alzheimer’s diagnosis. These findings provided strong evidence of disease reversal and highlighted a potential biomarker for future human trials.
“We were very excited and encouraged by our results,” said Andrew A. Pieper, MD, PhD, senior author of the study and Director of the Brain Health Medicines Center. “Restoring the brain’s energy balance achieved pathological and functional recovery in both lines of mice with advanced Alzheimer’s. Seeing this effect in two very different animal models strengthens the idea that restoring the brain’s NAD+ balance might help patients recover from Alzheimer’s.”
A Shift in Perspective
The findings suggest a fundamental change in how Alzheimer’s could be approached. “The key takeaway is a message of hope—the effects of Alzheimer’s disease may not be inevitably permanent,” said Dr. Pieper. “The damaged brain can, under some conditions, repair itself and regain function.”
Dr. Chaubey added, “Through our study, we demonstrated one drug-based way to accomplish this in animal models, and also identified candidate proteins in the human AD brain that may relate to the ability to reverse AD.”
Supplements vs. Targeted Therapy
Dr. Pieper cautioned against confusing this strategy with over-the-counter NAD+ precursors, which animal studies have shown can raise NAD+ to dangerously high levels that promote cancer. The research relies on P7C3-A20, a compound that helps cells maintain healthy NAD+ balance without pushing levels beyond their normal range.
“This is important when considering patient care, and clinicians should consider the possibility that therapeutic strategies aimed at restoring brain energy balance might offer a path to disease recovery,” said Dr. Pieper.
Next Steps: Toward Human Trials
The research opens the door to additional studies and eventual testing in people. The technology is currently being commercialized by Glengary Brain Health.
“This new therapeutic approach to recovery needs to be moved into carefully designed human clinical trials to determine whether the efficacy seen in animal models translates to human patients,” Dr. Pieper explained. “Additional next steps for the laboratory research include pinpointing which aspects of brain energy balance are most important for recovery, identifying and evaluating complementary approaches to Alzheimer’s reversal, and investigating whether this recovery approach is also effective in other forms of chronic, age-related neurodegenerative disease.”
