Alzheimer’s may be reversed by recharging the brain’s mitochondria

Scientists at Scripps Research have found something that could fundamentally change how we think about Alzheimer’s disease.

In a study published in the journal Advanced Science in January 2024, researchers identified the precise point in brain cell chemistry where things go wrong in Alzheimer’s patients, and then used a small molecule to fix it.

The result?

Neuron-to-neuron connections, which had withered and broken apart in Alzheimer’s nerve cell models, were largely restored.

This is not a vague promise of future medicine. The team worked with nerve cell models derived directly from the stem cells of actual Alzheimer’s patients, and in those models, the approach worked. Around three quarters of synapses where signaling had been lost were successfully re-energized.

This matters because those synaptic connections are memory. When they go, so does the ability to form new thoughts, recognize faces, and hold onto the present moment.

The lead researcher, Dr. Stuart Lipton, a clinical neurologist and professor at Scripps Research, put it plainly: the goal was to repair the metabolic activity in the mitochondria and, in doing so, salvage the brain’s energy production.

It worked.

How the Study Was Conducted

To understand what the team did, it helps to know what mitochondria actually are.

Mitochondria are the energy factories of every cell in your body. They convert nutrients into a usable form of energy called ATP. Your brain alone burns through roughly 20% of your body’s total energy, making it one of the most energy-hungry organs in existence.

For nerve cells, energy is not optional. They need a constant, reliable supply of ATP just to stay alive and to maintain the web of connections that allow memory and thought to function.

The Scripps team focused on a specific cellular process happening inside the mitochondria called the Krebs cycle, sometimes also referred to as the TCA cycle. Think of it as a spinning engine that keeps generating fuel. For that engine to keep turning, it needs a steady supply of key molecules at each stage of the cycle.

In Alzheimer’s patients, the researchers found the engine was stalling.

Specifically, they traced the problem to a chemical called succinate, a molecule that plays a critical role in powering the Krebs cycle forward. In Alzheimer’s neurons, abnormal levels of nitric oxide were interfering with the process through a reaction called S-nitrosylation, which essentially jammed the machinery responsible for producing succinate.

Without enough succinate, the cycle slowed, ATP production dropped, and the neurons began to starve.

The team then tested a solution: a modified analog of succinate engineered to pass through cell membranes, something normal succinate molecules cannot do easily. They introduced this analog into the Alzheimer’s neuron models to see if bypassing the blockage could jumpstart energy production.

It could.

Findings From the Study

The results were striking.

Neuron connections that had been lost were rebuilt. The synapses, which are the physical contact points between nerve cells where communication happens, were restored in a significant portion of the affected cells.

To be precise, the research published in Advanced Science showed that energy production was restored in roughly three out of four synapses that had gone dark.

This is not a cosmetic fix. Synaptic loss is one of the most reliable predictors of cognitive decline in Alzheimer’s patients. When synapses break apart, memory fades. When synapses are restored, the communication pathway between neurons can function again.

The broader implication of the study is just as important as the specific finding: mitochondrial dysfunction may not just be a symptom of Alzheimer’s disease. It may be one of its root causes.

Separate research from the Mayo Clinic and Jackson Laboratory, published in the journal Alzheimer’s and Dementia in 2025, reinforced this idea. That study found that a deficiency in a component of the mitochondria called Complex I was enough on its own to generate Alzheimer’s-like changes in brain tissue, including disruptions to synaptic function and transcriptomic patterns that mirror those seen in late-onset Alzheimer’s patients.

Crucially, those changes were partially reversed by a targeted treatment called CP2, a neuroprotective small molecule that mildly inhibits Complex I activity.

Two independent research teams, working from different angles, arriving at the same conclusion: fix the mitochondria, and the brain may begin to heal.

Here Is What Most People Get Wrong About Alzheimer’s Research

For decades, Alzheimer’s research has been dominated by one theory: the disease is caused by the buildup of a protein called amyloid beta, which clumps together in the brain and triggers a cascade of damage.

The scientific community invested billions of dollars and decades of effort into drugs that clear amyloid from the brain.

Many of them failed.

Some worked at clearing amyloid and still did not meaningfully slow cognitive decline in patients. That raised an uncomfortable question: what if amyloid is not the beginning of the story?

What if it is a consequence?

The emerging evidence around mitochondria suggests that energy failure in brain cells may come first, triggering a chain reaction that eventually leads to amyloid accumulation, tau protein tangles, and the progressive loss of neurons.

As researchers at Frontiers in Pharmacology noted in a 2025 review of mitochondrial therapies for Alzheimer’s, the mitochondrial cascade hypothesis proposes that inherited mitochondrial variation, aging, and environmental stress all converge to determine how resilient neurons are. When that resilience fails, amyloid and tau pathology follow. This means that therapies focused only on clearing amyloid may not fully reverse neuronal dysfunction that has already taken hold.

That reframing is significant. It suggests that targeting the energy crisis in the brain, rather than cleaning up the debris it leaves behind, could be the more effective strategy, especially if applied early.

How This Research Applies to Real Life

More than 55 million people worldwide are currently living with Alzheimer’s disease or a related form of dementia. According to Alzheimer’s Disease International, a new case emerges somewhere in the world every three seconds.

In the United States alone, an estimated 7.4 million Americans aged 65 and older are living with Alzheimer’s in 2026, and that number is projected to nearly double by 2060 without a major scientific breakthrough.

The urgency is real. So is the hope that this line of research represents.

What makes the mitochondria approach particularly promising is its specificity. Rather than flooding the brain with broadly acting drugs, researchers are targeting a precise chemical bottleneck. The Scripps team identified exactly where the Krebs cycle stalls in Alzheimer’s neurons and designed a molecule to slip past that blockage.

That kind of precision is what modern medicine has been striving toward.

What Comes Next for Mitochondrial Therapies

The research is still in early stages.

The Scripps study was conducted in nerve cell models, not in living patients. That distinction matters. What works in a lab dish does not always translate into a working treatment in a human brain.

Researchers will need to conduct animal studies, then safety trials, and eventually large-scale clinical trials before any mitochondria-targeting treatment reaches patients. That process typically takes years, sometimes more than a decade.

But the direction is meaningful.

A separate 2024 study published in Alzheimer’s and Dementia explored an entirely different mitochondrial approach: actually transplanting healthy mitochondria directly into Alzheimer’s neurons. In laboratory models, this restored mitochondrial membrane potential, increased ATP levels, and reduced cell death signals. The cells, in effect, came back to life.

Multiple teams, multiple methods, converging on the same target.

That kind of scientific momentum is not accidental.

Why the Mitochondria Angle Changes the Conversation

For patients and families living with Alzheimer’s, the conversation around this disease has long felt trapped between hope and helplessness.

Treatments exist to manage symptoms. Nothing has reliably stopped or reversed the disease in a broad population.

That is part of what makes the mitochondrial energy angle so worth paying attention to. It does not just offer a new drug candidate. It offers a new framework for understanding what Alzheimer’s actually is, namely, in part, a disease of energy failure, of neurons slowly starving in a brain that can no longer fuel itself properly.

If that is true, then the path forward is not just about clearing the damage that has already been done. It is about restoring the conditions the brain needs to repair itself.

That is a different kind of medicine. And it may be the kind Alzheimer’s has needed all along.

The researchers at Scripps said they thought that if they could repair metabolic activity in the mitochondria, they might be able to salvage energy production. They were right. The question now is how far that insight can travel.

For the more than 55 million people living in the long shadow of this disease, the answer cannot come soon enough.

References and Further Reading