Now, researchers led by scientists at the University of Wisconsin-Madison believe they may have uncovered the missing piece of the puzzle.

In a new study published in Nature, the team used extremely detailed computer simulations to study plasma flows. Their results suggest that large magnetic fields can emerge when turbulent plasma develops organized jet-like flows. The discovery introduces a new explanation for how cosmic magnetic fields form and could help scientists better understand everything from black hole formation to space weather near Earth.

“Magnetic fields across the cosmos are large-scale and ordered, but our understanding of how these fields are generated is that they come from some kind of turbulent motion,” says the study’s lead author Bindesh Tripathi, a former UW-Madison physics graduate student and current postdoctoral researcher at Columbia University. “Given that turbulence is known to be a destructive agent, the question remains, how does it create a constructive, large-scale field?”

Searching for Order in Cosmic Turbulence

Before focusing on three-dimensional (3D) magnetic fields, Tripathi had studied systems involving fluid flows and two-dimensional (2D) magnetic fields. While examining images and videos of 3D magnetic turbulence, he noticed that large-scale magnetic structures resembled the shapes of large-scale flows.

However, applying fluid dynamics directly to magnetic fields was not straightforward. Fluid flow problems can often be simplified into two dimensions, but magnetic field generation must be solved in full 3D space, making the calculations far more difficult.

To tackle the challenge, the researchers changed two important aspects of previous studies.

The first involved adding a constantly renewed velocity gradient into the simulations. A velocity gradient occurs when different parts of a system move at different speeds. For example, a cyclist who suddenly hits a curb experiences a sharp velocity gradient when the bike stops but the rider’s momentum continues forward. Similar effects occur throughout the universe, including inside the Sun and during neutron star mergers. The team suspected these gradients could play a major role in shaping magnetic fields.

Massive Supercomputer Simulations Reveal a Pattern

The second major step was computational power. The researchers carried out what may be the most detailed simulation yet of magnetic fields interacting with unstable velocity gradients. Their model used 137 billion grid points in 3D space.

In total, the team performed roughly 90 simulations, producing 0.25 petabytes of data and consuming nearly 100 million CPU hours on Purdue University’s Anvil supercomputer.

“We start our simulations with a flow that has a velocity gradient, then we add some tiny perturbations, like moving one fluid particle infinitesimally, we let that perturbation propagate over the system and grow, and then analyze the data over time,” Tripathi says. “Initially, these perturbations lead to turbulent flows and magnetic fields in small-scale structures, then, over time, they emerge into larger, ordered structures.”

When the researchers repeated the simulations without maintaining the large-scale velocity gradient, the organized magnetic structures never formed. Instead, the system remained chaotic and disordered.

“So that’s really the main key: to have a steady, large-scale gradient in velocity,” he emphasizes.

Solving a Long-Standing Magnetic Field Problem

Scientists have studied magnetic dynamos, the processes that generate magnetic fields, for roughly 70 years. Yet most theoretical models have struggled to produce the large, ordered magnetic structures that astronomers actually observe in space.

Adds Paul Terry, physics professor at UW-Madison and senior author of the study: “Magnetic field generation via dynamos has been extensively studied for 70 years, with the frustrating result that the generated fields almost always end up at small scales and highly disordered, unlike observations. This work, therefore, potentially resolves a long-standing issue.”

Although the new theory cannot be directly tested in distant cosmic environments, earlier laboratory experiments appear to support the findings. In 2012, researchers at the Wisconsin Plasma Physics Laboratory observed magnetic field behavior that existing theories could not explain. The new model developed by Tripathi and his colleagues aligns more closely with those puzzling experimental results.

Implications for Black Holes, Neutron Stars, and Space Weather

The findings could have important implications across astrophysics.

“This work has the potential to explain the magnetic dynamics relevant in, for example, neutron star mergers and black hole formation, with direct applications to multimessenger astronomy,” Tripathi says. “It may also help better understand stellar magnetic fields and predict gas ejections from the Sun toward the Earth.”

The research was supported by the National Science Foundation (2409206) and U.S. Department of Energy (DE-SC0022257) through the DOE/NSF Partnership in Basic Plasma Science and Engineering. The Anvil supercomputer at Purdue University was used through allocation TG-PHY130027 from the Advanced Cyberinfrastructure Coordination Ecosystem: Services & Support (ACCESS) program, supported by the National Science Foundation (2138259, 2138286, 2138307, 2137603 and 2138296).

The USC team linked elevated cPLA2 activity to Alzheimer’s risk while studying people who carry the APOE4 gene, the strongest known genetic risk factor for the disease. Although many APOE4 carriers never develop Alzheimer’s, researchers found that those with higher cPLA2 activity were more likely to experience the disease.

Because cPLA2 also supports healthy brain function, scientists needed to find a way to reduce its harmful activity without completely shutting the enzyme down. Another challenge involved identifying compounds small enough to cross the blood-brain barrier so they could reach the brain effectively.

“In this study, we identified compounds that act selectively on cPLA2, with minimal effects on related PLA2 enzymes that are important for normal cellular function,” said senior author Hussein Yassine, director of the Center for Personalized Brain Health at the Keck School of Medicine of USC. “Across cell-based and animal models, cPLA2 activity was reduced at low concentrations, indicating that the compounds are potent in brain-relevant systems.”

Screening Billions of Molecules for Alzheimer’s Drug Candidates

To search for potential treatments, researchers used large-scale computational screening methods to evaluate billions of possible molecules. The team prioritized compounds predicted to selectively target cPLA2, enter the brain, and remain active under biologically relevant conditions. The screening methods were developed by Vsevolod “Seva” Katritch of the USC Dornsife College of Letters, Arts and Sciences and the USC Michelson Center for Convergent Bioscience.

After narrowing down the list of candidates, pharmacologist Stan Louie of the USC Alfred E. Mann School of Pharmacy and Pharmaceutical Sciences led efforts to prepare the compounds for testing in animal models and measure how effectively they reached the brain.

One cPLA2 inhibitor emerged as the leading candidate after reducing harmful cPLA2 activation in human brain cells exposed to Alzheimer’s-related stress conditions.

Promising Results in Early Brain and Animal Studies

In mouse studies, the compound successfully crossed the blood-brain barrier and influenced neuroinflammatory pathways linked to Alzheimer’s disease. The results suggest that selectively inhibiting cPLA2 may represent a promising strategy for treating neurodegenerative disorders.

“Our goal is to find out whether targeting inflammation can alter Alzheimer’s risk — particularly in APOE4 carriers,” Yassine said. “This next phase focuses not on promises, but on carefully determining whether modulating this pathway is safe, feasible, and ultimately meaningful for human disease.”

In addition to Yassine, Louie, and Katritch, the study was led by co-first authors Anastasiia V. Sadybekov, Marlon Vincent Duro, and Shaowei Wang, all of USC. Other contributors included Brandon Ebright, Dante Dikeman, Cristelle Hugo, Bilal Ersen Kerman, Qiu-Lan Ma, Antonina L. Nazarova, Arman A. Sadybekov, and Isaac Asante.

The research received funding from the National Institute on Aging (U01AG094622, RF1AG076124, R01AG055770, R01AG067063, R01AG054434, R21AG056518, and P30AG066530); the National Institute of General Medical Sciences (R01GM147537); Department of Defense (W81XWH2110740), the Alzheimer’s Drug Discovery Foundation (GC-201711-2014197); USC CTSI KL2 (UL1 TR000004); and donations from the Vranos and Tiny Foundations and Lynne Nauss.

Disclosure: Yassine, Katritch, and Louie are founders of PeBRx, a company developing cPLA2 inhibitors. No other authors reported competing interests.

The newly described species was announced in the journal Zootaxa after researchers confirmed that the unusual octopus had never been documented before.

The animal was first spotted during a 2015 deep-sea expedition aboard the exploration vessel E/V Nautilus. The mission was carried out in partnership with the Charles Darwin Foundation (CDF) and the Galápagos National Park Directorate. Researchers used a remotely operated underwater vehicle (ROV) to investigate the seafloor near Darwin Island, located at the northern edge of the Galápagos archipelago.

Deep-Sea Discovery Near an Underwater Mountain

As the ROV explored an underwater mountain roughly 5,800 feet (1,773 meters) below the ocean surface, researchers noticed something unusual moving across the seafloor: a tiny octopus with a striking blue color.

The scientists’ immediate reactions were captured in the expedition audio recordings.

“He’s tiny!”

“It’s blue!”

Using the ROV, the team collected the octopus specimen and also recorded video footage of two others that appeared to be the same species. After returning to the Galápagos, the researchers brought dozens of deep-sea specimens to the Charles Darwin Research Station for examination.

Among all the collected animals, the little octopus immediately stood out. About the size of a golf ball, it looked unlike any known species. Researchers at the station contacted octopus expert Janet Voight and sent her photographs of the animal for identification.

“Right away, I knew it was something really special,” says Voight, curator emerita of invertebrates at the Field Museum in Chicago and the lead author of the study describing the new species. “I’d never seen anything like it.”

Scientists Use CT Scans To Study Rare Octopus

The specimen was carefully preserved in alcohol and formalin before being shipped from the Galápagos to Chicago, where Voight examined it at the Field Museum.

Normally, identifying a new octopus species requires scientists to dissect the specimen and closely study features such as the mouth, beak, and teeth. However, the researchers faced a major challenge because they had only one confirmed specimen.

“When you describe a new species of octopus, you have to look at all the parts, including the mouth, the beak, and the teeth. And to see those things, you have to cut the specimen open. We only had the one specimen, so I didn’t want to take it apart,” says Voight.

Instead, the team turned to advanced imaging technology. Stephanie Smith, manager of the Field Museum’s X-ray computed tomography laboratory, helped create highly detailed micro CT scans of the octopus.

“Because CT imaging is non-destructive, it’s especially important for type specimens like this one. And that’s great for me because people are often bringing me these incredibly rare and stunningly beautiful specimens that I get the privilege of virtually opening up,” says Smith, a co-author of the paper describing the new species. “There’s nothing like spending the day looking at something no other human has ever seen.”

CT scanning works by combining thousands of X-ray images into a detailed 3D model that reveals both the exterior and internal anatomy of an object without physically cutting into it.

For the tiny blue octopus, the scans provided clear views of internal organs and mouth structures, allowing scientists to officially classify it as a new species and better understand its relationship to other octopuses.

“What really struck me was that the scan of the little octopus revealed so much information on its internal organ systems — usually, soft-part imaging using micro CT requires the use of heavy-metal-based contrast agents whose use would not be desirable with such a rare specimen. This made the 3D modeling of relevant organs really an easy task,” says Alexander Ziegler, a researcher at the University of Bonn in Germany and senior author of the paper.

A New Species Highlights Ocean Mysteries

The octopus has been named Microeledone galapagensis. Beyond the discovery itself, the species also marks an important milestone for Voight, who has spent more than 40 years studying octopus evolution. This is the first time she has officially led the description of a new octopus species.

“These are little octopuses that live in the deep sea, and hardly anybody on Earth has ever gotten to see them. I just feel lucky that I got to work with them,” says Voight. “If you took all the land on Earth and pieced it together, you would not cover the Pacific Ocean. The oceans are so big, and there’s so much left to explore.”

Researchers say discoveries like this are also important for protecting fragile ocean ecosystems that remain poorly understood.

“When we were sorting through dozens of specimens collected during the expedition, this tiny blue octopus fascinated us,” said Salome Buglass, marine scientist at the University of California of Los Angeles, former researcher at the Charles Darwin Foundation and co-author of the paper. “There was something unusual about it, so we went out of our way to find the right person to help us identify what it was. Getting the specimen to Janet was a long process, but one I would gladly repeat if it means getting to know the most precious parts of our ocean just a little bit better. Discoveries like these remind us how much of the deep ocean in Galápagos remains unexplored. Every new species helps us better understand these hidden ecosystems and why protecting them matters.”

Research from the University of Exeter found that older adults who drank nitrate rich beetroot juice twice a day for two weeks saw their blood pressure fall. The same effect did not appear in younger adults, even though beetroot juice also changed their oral microbiome.

The study, published in Free Radical Biology and Medicine, is the largest of its kind to examine how dietary nitrate affects the mouth bacteria, nitric oxide biology, and blood vessel responses of younger and older adults.

Why the Mouth Matters

Nitrate is found naturally in many vegetables and plays an important role in the body. Beetroot is especially rich in nitrate, but it is not the only option. Spinach, arugula, fennel, celery, and kale are also good dietary sources.

The key step happens before nitrate reaches the bloodstream. Certain bacteria in the mouth help convert nitrate from food into compounds that eventually support the production of nitric oxide. Nitric oxide helps blood vessels relax and function properly, which is important for healthy blood pressure regulation.

When the balance of oral bacteria shifts in the wrong direction, that nitrate to nitric oxide pathway may become less efficient. The Exeter team found evidence that beetroot juice changed the oral microbiome in older adults in a way that appeared to support this pathway.

A Two Week Beetroot Juice Test

The trial included 39 adults under age 30 and 36 adults in their 60s and 70s, recruited through the NIHR Exeter Clinical Research Facility. It was supported by the Exeter Clinical Trials Unit and funded through a BBSRC Industrial Partnership Award.

Participants completed two separate two week phases. In one phase, they drank regular doses of nitrate rich beetroot juice. In the other, they drank a placebo version of the juice with the nitrate removed. A two week “wash out” period separated the phases so the researchers could reset the conditions before testing the next drink.

The team then used bacterial gene sequencing to study which microbes were present in the mouth before and after each condition.

Older Adults Responded Differently

Both age groups showed significant changes in the oral microbiome after drinking nitrate rich beetroot juice. However, the changes were not the same in younger and older participants.

Among older adults, beetroot juice was linked to a notable drop in Prevotella, a group of mouth bacteria that the researchers described as potentially harmful in this context. At the same time, bacteria associated with health benefits, including Neisseria, became more abundant.

The older group also began the study with higher average blood pressure than the younger group. After the nitrate rich beetroot juice phase, their blood pressure fell. That reduction was not seen after the placebo drink, and it was not observed in the younger adults.

The Nitric Oxide Connection

The results point to a possible reason beetroot juice may be especially useful later in life. Older adults tend to produce less nitric oxide as they age, and reduced nitric oxide availability can affect blood vessel function.

Study author Professor Anni Vanhatalo, of the University of Exeter, said: “We know that a nitrate-rich diet has health benefits, and older people produce less of their own nitric oxide as they age. They also tend to have higher blood pressure, which can be linked to cardiovascular complications like heart attack and stroke. Encouraging older adults to consume more nitrate-rich vegetables could have significant long term health benefits. The good news is that if you don’t like beetroot, there are many nitrate-rich alternatives like spinach, rocket, fennel, celery and kale.”

The findings suggest that beetroot juice may not act only through the nutrients it delivers. It may also work by changing the tiny ecosystem in the mouth that helps unlock those nutrients.

Related Research Adds to the Picture

Follow up work and related studies have continued to strengthen the idea that oral bacteria are central to how nitrate affects the body.

A 2025 randomized, double blind, placebo controlled crossover study of 15 older adults with treated high blood pressure found that four weeks of nitrate rich beetroot juice selectively changed the oral microbiome, increasing Neisseria and decreasing Veillonella, while the intestinal microbiome did not significantly change. The same research program reported that nitrate intake affected nitrate metabolism but did not produce sustained improvements in blood pressure or vascular function in that treated hypertension group, showing that the response may depend on health status, medications, study design, and the bacteria present at baseline.

A 2026 pilot study also highlighted the importance of the mouth in nitrate biology. It found that chlorhexidine, an antiseptic mouthwash, disrupted nitrate processing and reduced gastric nitric oxide synthesis, while dietary nitrate supplementation partly preserved microbial function and nitric oxide related signaling during antiseptic use.

Other work has raised similar questions about antibacterial mouth rinses. A 2025 Scientific Reports study in rats found that a nitrate and antioxidant mouth rinse supported nitrate and nitrite reducing oral bacteria and was associated with lower blood pressure compared with chlorhexidine treatment. Because that study was conducted in animals, the findings cannot be directly applied to people, but they add to the broader evidence that oral bacteria can influence the nitrate pathway.

A Potential Nutrition Strategy for Healthy Aging

Co-author Professor Andy Jones, of the University of Exeter, said: “This study shows that nitrate-rich foods alter the oral microbiome in a way that could result in less inflammation, as well as a lowering of blood pressure in older people. This paves the way for larger studies to explore the influence of lifestyle factors and biological sex in how people respond to dietary nitrate supplementation.”

The findings do not mean beetroot juice is a replacement for medication or other proven ways to manage blood pressure. However, they do suggest that nitrate rich vegetables could be a practical addition to a heart healthy lifestyle, particularly for older adults.

They also point to a more personalized future for nutrition. Two people can eat the same nitrate rich foods but respond differently, partly because their oral microbiomes may not process nitrate in the same way.

What Comes Next

The Exeter researchers say larger studies are needed to understand why some people respond more strongly than others. Future research may help reveal how lifestyle, sex, age, oral hygiene habits, and baseline microbiome differences shape the effects of dietary nitrate.

Dr. Lee Beniston FRSB, Associate Director for Industry Partnerships and Collaborative Research and Development at BBSRC, said:

“This research is a great example of how bioscience can help us better understand the complex links between diet, the microbiome and healthy aging. By uncovering how dietary nitrate affects oral bacteria and blood pressure in older adults, the study opens up new opportunities for improving vascular health through nutrition. BBSRC is proud to have supported this innovative partnership between academic researchers and industry to advance knowledge with real-world benefits.”

Together, the evidence points to a striking idea: one path to healthier blood vessels may begin not in the heart, but in the mouth.

The issue is not that bananas are unhealthy. Instead, it comes down to how certain ingredients interact after they are blended together. In a study published in the Royal Society of Chemistry journal Food & Function, researchers found that fruits with high levels of an enzyme called polyphenol oxidase, or PPO, can sharply reduce the amount of flavanols your body absorbs from a smoothie.

Flavanols are natural plant compounds linked to heart and cognitive health. They are found in foods such as apples, pears, blueberries, blackberries, grapes, cocoa, and other common smoothie ingredients.

The Enzyme Behind Browning Fruit

“We sought to understand, on a very practical level, how a common food and food preparation like a banana-based smoothie could affect the availability of flavanols to be absorbed after intake,” said lead author Javier Ottaviani, director of the Core Laboratory of Mars Edge, which is part of Mars, Inc., and an adjunct researcher with the UC Davis Department of Nutrition.

Anyone who has sliced an apple or peeled a banana has seen PPO in action. When the fruit is cut, bruised, or exposed to air, the enzyme helps trigger the browning reaction. The UC Davis team wanted to know whether that same process could also affect the nutrients people hope to get from smoothies.

To test the idea, the researchers used freshly prepared smoothies made with ingredients that naturally contain different amounts of PPO. Bananas have high PPO activity, while mixed berries have low PPO activity.

Bananas Versus Berries

Participants drank a banana based smoothie, a mixed berry smoothie, and a flavanol capsule used as a control. The researchers then analyzed blood and urine samples to see how much of the flavanols became available in the body.

The difference was striking. People who drank the banana smoothie had 84% lower flavanol levels compared with the control. In contrast, the low PPO mixed berry smoothie produced flavanol levels similar to the capsule control.

“We were really surprised to see how quickly adding a single banana decreased the level of flavanols in the smoothie and the levels of flavanol absorbed in the body,” Ottaviani said. “This highlights how food preparation and combinations can affect the absorption of dietary compounds in foods.”

The study also included a second test in which participants consumed flavanols along with a high PPO banana drink, but the ingredients were kept from contacting each other before intake. Flavanol levels were still reduced, which suggests PPO activity may continue to matter after consumption, possibly in the stomach.

What This Means for Your Smoothie

The findings do not mean bananas are bad for you. Bananas provide fiber, potassium, and other nutrients, and they can still be part of a healthy diet. The more specific lesson is that bananas may not be the best choice when the goal is to maximize flavanol intake from berries, grapes, cocoa, or other flavanol rich foods.

The Academy of Nutrition and Dietetics has issued a dietary recommendation suggesting 400 to 600 milligrams of flavanols per day for cardiometabolic health. Those compounds are found in foods such as tea, apples, berries, grapes, and cocoa.

For people trying to boost flavanols through smoothies, Ottaviani recommends pairing flavanol rich fruits like berries with ingredients that have low PPO activity. Good options include pineapple, oranges, mango, or yogurt.

Bananas can still be eaten on their own or used in smoothies where flavanol intake is not the main goal. But if your smoothie is built around berries, grapes, or cocoa, the better strategy may be to leave the banana out or enjoy it separately.

A Small Study With a Practical Message

The original study was controlled and carefully designed, but it was also small. The first part included eight healthy men, and a second test included 11 participants. That means the results are useful and intriguing, but they should not be treated as the final word for every person or every diet.

Nutrition experts commenting on the research have also urged people not to overreact. Smoothies with bananas can still be nutritious, especially as part of a varied diet. Individual digestion, food patterns, and overall nutrient intake all matter.

The best takeaway is simple: ingredient combinations can change what your body gets from food. A smoothie is not just a pile of nutrients in a glass. How the ingredients interact can affect the final nutritional payoff.

Why Flavanols Remain a Hot Research Topic

The smoothie finding fits into a larger area of nutrition research focused on flavanols and other plant bioactives. These compounds are being studied for possible benefits related to blood flow, blood pressure, cholesterol, glucose regulation, and brain health. The Academy of Nutrition and Dietetics guideline described moderate evidence for 400 to 600 milligrams per day of flavanols to support cardiometabolic health, while emphasizing food sources rather than supplements.

Recent cocoa flavanol research has produced a more nuanced picture for cognition. In the COSMOS related research program, cocoa extract containing 500 milligrams of flavanols per day did not show broad cognitive benefits for everyone, but some analyses suggested potential benefit among older adults with lower habitual diet quality.

That makes the smoothie study especially practical. If people are choosing berries, cocoa, or grapes for their flavanols, then preparation and pairing may matter. More research is still needed, but the idea is easy to apply at home.

Better Smoothie Combos for Flavanols

If the goal is a flavanol friendly smoothie, try combining berries with low PPO ingredients such as mango, pineapple, orange, or yogurt. These options can keep the drink sweet and creamy without adding the high PPO activity found in bananas.

For banana lovers, there is no need to give them up. Just consider separating your smoothie goals. Use bananas when you want creaminess, potassium, and sweetness. Use berries, cocoa, grapes, or apples with lower PPO partners when you want to preserve more flavanols.

The research may also point beyond smoothies. Ottaviani said tea, another major source of flavanols, could be affected by preparation methods that change how many flavanols are available for absorption.

“This is certainly an area that deserves more attention in the field of polyphenols and bioactive compounds in general,” said Ottaviani.

Jodi Ensunsa, Reedmond Fong, Jennifer Kimball and Alan Crozier, all affiliated with the UC Davis Department of Nutrition and researchers affiliated with the UC Davis Department of Internal Medicine, University of Reading, King Saud University and Mars, Inc. contributed to the research.

The study was funded by a research grant from Mars, Inc., which collaborates with researchers to study potential benefits of cocoa flavanols for human health.

The findings add to growing evidence that aging may be strongly influenced by the hypothalamus, a small but powerful brain region that regulates metabolism, hormones, body temperature, sleep, and stress responses. Researchers increasingly view the hypothalamus as a central command center for aging itself.

A Brain Protein That Declines With Age

The study, led by Lige Leng and colleagues at Xiamen University in China, focused on Menin, a protein that helps suppress inflammation in the brain. Earlier work had already shown that Menin plays an important role in controlling neuroinflammatory activity. The team wanted to know whether losing this protective protein might contribute to aging.

Their experiments revealed that Menin levels dropped sharply in the hypothalamus as mice grew older. The decline occurred specifically in neurons within the ventromedial hypothalamus (VMH), a region linked to metabolism and systemic aging. Interestingly, Menin levels did not significantly decrease in nearby support cells such as astrocytes or microglia.

To investigate what this loss might mean, the researchers engineered mice in which Menin activity could be selectively reduced. The effects were striking. Younger mice with lower Menin levels developed increased brain inflammation, thinning skin, lower bone mass, impaired balance, memory problems, and a shorter lifespan compared with normal mice.

The results suggest that Menin may act as a protective “anti-aging” factor inside the brain.

The D-Serine Connection

One of the most surprising discoveries involved D-serine, an amino acid that also functions as a neurotransmitter in the brain. D-serine helps regulate communication between neurons and is important for learning and memory.

When Menin levels fell, D-serine production also dropped. The researchers traced this effect to reduced activity of an enzyme required for D-serine synthesis, which itself appears to be regulated by Menin.

D-serine naturally occurs in foods including soybeans, eggs, fish, and nuts, and it is also sold as a dietary supplement.

The connection caught researchers’ attention because other studies have linked declining D-serine levels with aging-related cognitive impairment and reduced synaptic plasticity, the brain’s ability to strengthen neural connections involved in memory and learning.

Reversing Signs of Aging in Mice

The researchers then tested whether restoring Menin could reverse age-related decline.

They delivered the Menin gene directly into the hypothalamus of elderly mice that were about 20 months old, roughly equivalent to late-life aging in humans. Just 30 days later, the animals showed measurable improvements in learning, memory, balance, skin thickness, and bone density.

The improvements were accompanied by increased D-serine levels in the hippocampus, a brain region essential for memory formation.

The team also tested whether D-serine supplementation alone could help. After three weeks of supplementation, older mice displayed better cognitive performance, although the treatment did not reverse the physical aging markers seen in skin and bone tissue.

That distinction suggests Menin likely affects aging through several interconnected biological pathways, not just D-serine production alone.

Why the Hypothalamus Is Becoming a Major Focus in Aging Research

Interest in the hypothalamus has grown rapidly in recent years as scientists uncover evidence that this brain region may coordinate many aspects of aging throughout the body.

More recent research has explored how age-related changes in hypothalamic DNA methylation and hormone signaling could contribute to neurodegenerative diseases such as Alzheimer’s. One 2024 study in Nature Communications found that the hypothalamus undergoes distinctive epigenetic changes with age and may influence pathways involving oxytocin and gonadotropin-releasing hormone (GnRH), both linked to aging and brain health.

Together, these findings strengthen the idea that aging is not simply the result of wear and tear across the body. Instead, some scientists suspect the brain may actively regulate parts of the aging process through inflammation, metabolism, and hormonal signaling.

Could D-Serine Help Humans?

Despite the excitement surrounding the findings, the research remains early and was conducted in mice, not humans. Scientists still do not know whether boosting Menin or supplementing with D-serine could safely slow aging or improve cognition in people.

Researchers also caution that altering powerful brain signaling pathways could have unintended consequences. More work is needed to understand why Menin declines with age, how long any benefits might last, and whether D-serine supplementation could produce side effects over time.

Still, the study offers an intriguing glimpse into how aging may one day be targeted more directly.

Leng said, “We speculate that the decline of Menin expression in the hypothalamus with age may be one of the driving factors of aging, and Menin may be the key protein connecting the genetic, inflammatory, and metabolic factors of aging. D-serine is a potentially promising therapeutic for cognitive decline.”

Leng also noted, “Ventromedial hypothalamus (VMH) Menin signaling diminished in aged mice, which contributes to systemic aging phenotypes and cognitive deficits. The effects of Menin on aging are mediated by neuroinflammatory changes and metabolic pathway signaling, accompanied by serine deficiency in VMH, while restoration of Menin in VMH reversed aging-related phenotypes.”

There are two forms of vitamin D supplements available: vitamin D2 and vitamin D3. Researchers have found that taking vitamin D2 supplements can lead to a drop in the body’s concentration of vitamin D3, which is the form our bodies naturally produce from sunlight and use most effectively to raise overall vitamin D levels.  

The study, published in Nutrition Reviews, analyzed data from randomized controlled trials and found that vitamin D2 supplementation resulted in a reduction in vitamin D3 levels compared to those not taking a vitamin D2 supplement. In many of the studies, the vitamin D3 levels went lower than in the control group. 

Emily Brown, PhD Research Fellow and Lead Researcher of the study from the University of Surrey’s Nutrition, Exercise, Chronobiology & Sleep Discipline, said: 

“Vitamin D supplements are important, especially between October and March, when our bodies cannot make vitamin D from sunlight in the UK.  However, we discovered that vitamin D2 supplements can actually decrease levels of vitamin D3 in the body, which is a previously unknown effect of taking these supplements. This study suggests that subject to personal considerations, vitamin D3 supplements may be more beneficial for most individuals over vitamin D2.”  

Professor Cathie Martin, Group Leader at the John Innes Centre, said:  

“This meta-analysis highlights the importance of ensuring plant-based vitamin D3 is accessible in the UK.” 

This research supports a previous study published in Frontiers in Immunology, led by Professor Colin Smith from the University of Surrey, which suggests that vitamin D2 and D3 do not have identical roles in supporting immune function. Vitamin D3 has a modifying effect on the immune system that could fortify the body against viral and bacterial diseases.   

Professor Colin Smith said: 

“We have shown that vitamin D3, but not vitamin D2, appears to stimulate the type I interferon signalling system in the body – a key part of the immune system that provides a first line of defence against bacteria and viruses. Thus, a healthy vitamin D3 status may help prevent viruses and bacteria from gaining a foothold in the body.” 

Further research into the different functionalities of vitamin D2 and D3 should be a priority in deciding whether vitamin D3 should be the first-line choice of vitamin D supplement, subject to individual requirements. 

Professor Martin Warren, Chief Scientific Officer at the Quadram Institute, said: 

 “Vitamin D deficiency represents a significant public health concern, especially during the winter months with significant deficiency across the UK population. This collaborative research effort aligns well with the Quadram Institute’s mission to deliver healthier lives through food innovation to enhance the nutrient density of the food we eat. Tackling this with the most effective form of vitamin D supplementation or fortification is of the utmost importance to the health of the nation.” 

The study also identified similar molecular patterns in human tissue, suggesting that important aspects of obesity-related nerve damage may occur in both mice and people. The findings were published in the journal Nature.

Obesity is known to affect much more than body weight and metabolism. It can alter immune activity, disrupt nerve structures, and reshape tissues throughout the body, increasing the risk of conditions such as type 2 diabetes, cardiovascular disease, stroke, neuropathy, and cancer. Despite these widespread effects, scientists have lacked tools capable of studying disease-related changes across an entire intact body in high detail.

To address that challenge, a research team led by Prof. Ali Ertürk, Director of the Institute for Biological Intelligence (iBIO) at Helmholtz Munich and Professor at LMU, developed MouseMapper. The AI framework uses foundation-model-based deep learning algorithms to analyze massive whole-body imaging datasets.

The system can automatically identify and segment 31 organs and tissue types while also mapping nerves and immune cells throughout the body. This allows researchers to examine how diseases affect multiple organ systems at the same time in intact mice.

“MouseMapper is built on a foundation model, which means it generalizes far beyond the data it was originally trained on,” says Ying Chen, co-first author of the study.

Transparent Mice and Whole-Body Imaging

To build the body maps, researchers first tagged nerves and immune cells in mice using fluorescent markers that glow under a microscope. They then used tissue-clearing methods to make the mice transparent while preserving the fluorescent signals, allowing scientists to see deep inside the body without cutting tissues apart.

Next, the team used advanced light-sheet microscopy to capture detailed three-dimensional images of entire mice. The process generated enormous datasets containing tens of millions of cellular structures from organs and tissues across the body.

MouseMapper then analyzed the images automatically, identifying anatomical regions, nerve networks, and immune-cell clusters throughout the animals.

This approach allowed the researchers to pinpoint exactly where inflammation and tissue damage appeared in organs such as fat tissue, muscle, liver, and peripheral nerves. Unlike earlier methods, scientists did not need to choose specific regions to study beforehand.

Obesity Linked to Facial Nerve Damage

To explore how obesity changes the body, the researchers fed mice a high-fat diet that produced obesity and metabolic problems similar to those seen in humans.

Using MouseMapper, the team found widespread alterations in immune-cell organization and nerve structures across the body. One of the most surprising discoveries involved the trigeminal nerve, a major facial nerve responsible for facial sensation and certain motor functions.

In obese mice, these sensory nerves showed a major reduction in branches and nerve endings, suggesting impaired nerve function. Behavioral tests supported that conclusion, showing that obese mice were less responsive to sensory stimulation compared to lean mice.

The researchers then focused on the trigeminal ganglion, which contains the cell bodies of facial sensory neurons. Through spatial proteomics analysis, they identified molecular changes linked to inflammation and nerve remodeling.

Importantly, many of the same molecular signatures were also found in trigeminal tissue from people with obesity. This suggests that the nerve-related changes observed in mice may also occur in humans.

“We revealed previously unknown structural and molecular changes in the trigeminal ganglion and its facial branches, and the same molecular signature was conserved in human tissue. This kind of finding simply cannot emerge from studying one organ at a time,” says Dr. Doris Kaltenecker, senior scientist at the Institute for Diabetes and Cancer (IDC) at Helmholtz Munich and first author of the study.

A New Tool for Studying Complex Diseases

The researchers believe MouseMapper could become an important tool for studying diseases that affect many organ systems simultaneously, including diabetes, cancer, neurodegenerative diseases, and autoimmune disorders.

Unlike earlier approaches focused on individual tissues or organs, MouseMapper provides an integrated whole-body analysis system that can identify disease hotspots throughout an organism.

The team has also made the whole-body datasets publicly available online so researchers around the world can explore obesity-related changes across organs and tissues.

“Our goal is to create a comprehensive framework for understanding how diseases affect the body as an interconnected system,” says Ali Ertürk. “Our long-term vision is to build truly realistic digital twins of mice in health and disease: cell-level atlases that we can query, perturb and screen in silico computationally. That would let us pinpoint the earliest changes a disease causes, design interventions to prevent them, and accelerate the discovery of new treatments while reducing the number of physical experiments we need to run.”

The work was supported by the European Research Council (Consolidator Grant CALVARIA to A. Ertürk; grant 949017 to M. Rohm), the German Research Foundation (DFG) under Germany’s Excellence Strategy within the Munich Cluster for Systems Neurology (SyNergy, ID 390857198, EXC 2145), DFG SFB 1052 (A9) and TR 296 (P03), the Collaborative Research Centre CRC 1744, the German Federal Ministry of Education and Research (NATON collaboration, 01KX2121, and HIVacToGC), the Vascular Dementia Research Foundation, the Nomis Heart Atlas Project Grant (Nomis Foundation), the Else-Kröner-Fresenius-Stiftung, the Edith-Haberland-Wagner Stiftung, the Helmut Horten Foundation, the EFSD and Novo Nordisk A/S Programme for Diabetes Research in Europe (to D. Kaltenecker), and the China Scholarship Council (to Y. Chen).