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Scientists have found that restoring a protein in the brain can partially reverse several signs of aging in mice, while a separate treatment with the amino acid D-serine improved cognitive performance. The findings suggest that changes in a protein called Menin, which is found in a small region of the brain, may play a role in age-related changes affecting memory, skin and bone health. The study, led by Lige Leng of Xiamen University in China, was published in the open-access journal PLOS Biology in March 2023. It identified a possible link between brain inflammation, metabolism and aging throughout the body. How Menin may affect agingThe researchers focused on the hypothalamus, a small region of the brain that helps regulate metabolism and other essential functions. The region also appears to play a role in how the body ages. Earlier research by Leng and his colleagues found that Menin helps control inflammation in the hypothalamus. They then investigated whether a decline in the protein could contribute to age-related changes. The researchers found that Menin levels declined with age in certain neurons in the ventromedial hypothalamus, a region involved in metabolism. The same decline was not observed in astrocytes and microglia, two types of cells that support and protect the brain. To determine whether the loss of Menin contributed to aging, rather than simply occurring alongside it, the scientists created genetically modified mice in which the protein could be selectively removed. Reducing Menin levels in younger mice increased inflammation in the hypothalamus and led to several aging-related changes, including reduced bone mass, thinner skin, cognitive decline and a slightly shorter lifespan. Link to D-serineThe loss of Menin also affected a chemical pathway involved in communication between brain cells. Mice with lower Menin levels had less D-serine, an amino acid that helps activate receptors involved in learning and memory. These receptors allow neurons to adjust the strength of their connections, a process important for storing information. An enzyme involved in producing D-serine was also affected, reducing the supply of the amino acid. The findings suggested that Menin could influence cognitive function through both inflammation and the chemical processes needed for communication between brain cells. D-serine is sometimes sold as a dietary supplement, but researchers caution that it should not be confused with L-serine, the form of serine found in dietary proteins. Foods such as soybeans, eggs, fish and nuts contain L-serine. The body can convert L-serine into D-serine, but the two forms are not interchangeable. Eating these foods is therefore not equivalent to receiving the experimental D-serine treatment used in the study. Restoring Menin in older miceThe researchers then tested whether increasing Menin levels could improve the health of 20-month-old mice. They introduced the Menin gene into the animals' hypothalamus, allowing cells in the region to produce more of the protein. After 30 days, the treated mice showed improvements in skin thickness and bone mass. They also performed better in tests measuring learning, cognition and balance. The treatment was accompanied by higher levels of D-serine in the hippocampus, a brain region important for learning and memory. The study also reported that restoring Menin extended the animals' lifespan. In a separate experiment, researchers gave mice D-serine through their drinking water for three weeks. The treatment improved cognitive performance, including in older mice. However, D-serine alone did not produce the broader physical improvements seen after Menin was restored. The study therefore did not show that D-serine supplementation could reverse aging throughout the body. Leng said the decline of Menin in the hypothalamus could be one factor driving aging and that the protein may connect genetic, inflammatory and metabolic processes involved in aging. Later research adds to the pictureSubsequent studies have examined related biological processes, although they do not directly confirm the entire Menin aging pathway. A study published in the Journal of Physiology and Biochemistry in March 2024 examined Menin in cultured mouse hippocampal cells exposed to the stress hormone corticosterone. Researchers found that a compound called itaconate increased Menin levels and reduced inflammation and a form of cell death. When Menin was silenced, those protective effects disappeared. However, because the work was conducted in cells rather than living animals, it did not show that the treatment could slow aging. Another 2024 study published in Cell Metabolism found that a different group of hypothalamic neurons communicates with fat tissue. Researchers at Washington University School of Medicine reported that maintaining or stimulating this system increased physical activity and extended lifespan in mice. The study involved a different biological pathway from Menin but provided further evidence that signals from the brain can affect aging elsewhere in the body. In January 2025, researchers at the Allen Institute analyzed about 1.2 million mouse brain cells in a study published in Nature. They found that some of the brain cells most affected by aging were concentrated around the third ventricle of the hypothalamus. Many of those cells showed lower activity in genes linked to neuron function and higher activity in genes associated with immune responses. The study did not test a treatment but identified the hypothalamus as an important area for further aging research. More D-serine may not always be betterLater research has also raised questions about whether increasing D-serine is always beneficial to the aging brain. A study published in Cellular and Molecular Life Sciences in April 2025 examined mice with features of Alzheimer's disease. Researchers found that an early increase in D-serine was associated with changes in brain signaling. When scientists genetically removed the enzyme responsible for producing D-serine, several later cognitive problems were prevented or reduced. The study involved a different disease model from the Menin research, but it showed that D-serine can have different effects depending on the underlying condition. Research published Sept. 16, 2026, in the Journal of Alzheimer's Disease found that feeding L-serine to mice in another Alzheimer's model increased blood levels of both L-serine and D-serine and partially restored the production of new neurons in the hippocampus. However, the treatment did not reduce the buildup of amyloid, a protein associated with Alzheimer's disease. That study examined L-serine and the production of new neurons, rather than D-serine supplementation as a treatment for human aging. Together, the findings suggest that serine metabolism may be an important area of research, but increasing serine is not necessarily beneficial in every situation. The form of serine, the disease or condition being studied and the outcome being measured all matter. What the findings mean for humansSome research has examined D-serine in humans, but there is no evidence that it can be used as an anti-aging treatment. A small randomized study published in 2016 involved 50 healthy older adults who received a single dose of D-serine. Participants performed better on one measure of a computerized maze task, but researchers found no significant improvement in other cognitive tests or measures of mood. The study did not demonstrate lasting memory benefits, slower aging or the safety of long-term D-serine use in older adults. The Menin research also leaves several questions unanswered. Scientists still need to determine why Menin levels decline with age, how much age-related physical and cognitive decline can be prevented by restoring the protein, and how long any benefits might last. Researchers also need to determine whether changing Menin levels or taking D-serine could cause unintended effects. The findings point to the possibility that some age-related changes may be influenced by signals originating in a small region of the brain. Understanding those signals could eventually help researchers find ways to preserve physical and cognitive function later in life. For now, however, the evidence points to an experimental biological pathway that requires further study, rather than a proven supplement or treatment capable of reversing human aging. Source: Science Daily

Scientists have found evidence suggesting that the first free-living cells on Earth may have emerged independently in two different forms — the ancestors of bacteria and archaea. An international team led by biologists at Heinrich Heine University Düsseldorf (HHU) examined the chemical reactions and enzymes involved in the earliest stages of life. Their findings, published in Science Advances, offer new clues about how the first cells produced essential substances and obtained energy. The researchers believe that around 4 billion years ago, two distinct types of primitive cells may have developed as life began moving beyond hydrothermal vents. “We would see two very different kinds of cells emerging, pioneer bacteria and pioneer archaea,” said Natalia Mrnjavac, a biologist at the University of Düsseldorf and lead author of the study. The team compared genomes, protein structures and chemical reactions to explore microbial evolution, including the period before cells became fully independent from their environment. Their study focused on about 420 chemical reactions that cells use to make essential components such as amino acids, RNA building blocks and vitamins. These reactions use substances that were available on the early Earth, including hydrogen, ammonia and carbon dioxide. Together, the reactions make up the basic metabolic network. The researchers found that while these reactions are extremely ancient and shared widely across life, the enzymes that perform them are not equally conserved between bacteria and archaea. William Martin, a biologist at HHU and senior author of the study, said the last universal common ancestor of all cells, known as LUCA, appears to have had enzymes for only about half of these reactions. The other reactions were likely carried out by naturally occurring metals in the environment where LUCA lived, the researchers said. This suggests that early life depended much more on its surroundings than modern cells do. “Metals that naturally occur in hydrothermal vents can replace a surprisingly large number of enzymes in metabolism,” said Harun Tüysüz, an inorganic chemist and co-author of the study. Joseph Moran of the University of Ottawa said early biochemical evolution appears to have involved a combination of enzyme-based and metal-based chemical reactions. The researchers also found cases in which bacteria and archaea appear to have developed different enzymes independently to perform the same essential metabolic functions. Mrnjavac said these parallel developments may have helped bacteria and archaea emerge as separate forms of free-living life. The findings suggest that although all life today shares a common genetic code and deep evolutionary connections, the earliest free-living cells may have had more than one independent origin. Source: Science Daily

Researchers have discovered that two highly poisonous flowering plants—wolfsbane and larkspur—could help pave the way for new medicines to treat pain, malaria and cancer, while also offering safer ways to control agricultural pests. The study, led by scientists from Michigan State University (MSU) and the Czech Academy of Sciences, identified a method to reproduce part of the plants' complex chemical process in the laboratory. The findings were published in the journal Molecular Plant. Although both plants can cause nerve damage and paralysis even in very small amounts, they also produce natural compounds with promising medicinal properties. "These plants have been used in different forms of medicine throughout the world for thousands of years," said Garret Miller, a former MSU researcher and now an assistant professor of biotechnology at the University of Michigan-Flint. He said understanding how these compounds are produced could open new opportunities for medical research and drug development. Researchers said plants are remarkable natural chemists that have evolved over millions of years to produce complex chemicals for survival. Many everyday products and medicines, including caffeine, menthol and vanillin, either come directly from plants or are inspired by plant chemistry. The research focused on a group of toxic compounds known as diterpenoid alkaloids, which are found in wolfsbane and larkspur. While these chemicals are highly poisonous, scientists believe they could also have valuable medical uses. For decades, researchers have struggled to understand how plants produce these complicated molecules. One of the best-known compounds in this group, aconitine, was first isolated nearly 200 years ago, but scientists have still been unable to fully produce it in a laboratory. The breakthrough came after researchers from the United States and the Czech Republic joined forces to trace the plants' natural chemical production process. The team studied several species of both plants and examined thousands of genes to identify those involved in producing the toxic compounds. After identifying key genes, the researchers inserted them into tobacco plants, which acted as living "biofactories" to test whether they could recreate the chemical pathway. The modified tobacco plants successfully produced atisinium, a member of the diterpenoid alkaloid family, using six different enzymes. Scientists said this marks an important first step toward understanding how these complex compounds are made and could eventually enable sustainable production of plant-based chemicals for medical research. Researchers believe the findings could support the future development of new medicines inspired by these natural compounds while reducing the need to harvest toxic plants from the wild. Source: Science Daily

Scientists in France say they have uncovered the basic building blocks behind the remarkable variety of birdsongs, finding that thousands of bird species create their songs using just eight fundamental sound patterns. The study analysed more than 116,000 recordings from over 3,000 bird species collected through a global birdsong database featuring recordings uploaded by volunteers. Researchers found that every birdsong is made up of combinations of eight basic sound "motifs" — three types of trills, three types of whistles, chaotic notes and harmonies. Birdsong is considered one of nature's most advanced forms of sound-based communication, but its immense variety has made it difficult for scientists to study on a global scale. Lead researcher Quentin Bacquelé, a PhD student at the University of Saint-Etienne, said birds from different parts of the world produce very different songs, making it challenging to identify common patterns. Using artificial intelligence (AI), the research team compared thousands of recordings and discovered that the wide range of birdsongs is built from the same small set of sound motifs. The study also found that the environment where birds evolved plays a major role in shaping their songs. Birds living in tropical forests tend to use simpler sounds, such as flat whistles, which can travel more effectively through dense vegetation and noisy natural surroundings. In contrast, birds in temperate forests often produce more complex songs with rapid trills and combinations of sounds that can carry more information over shorter distances. Researchers say this reflects an evolutionary trade-off. While more complex songs can communicate richer information, they are less effective over long distances in dense environments. Bacquelé said the findings could help scientists better understand how birds may adapt as human activity changes natural soundscapes through increasing noise pollution. He also stressed the importance of protecting natural habitats, noting that birdsongs are closely linked to the environments where they evolved. "If a forest disappears, the songs that evolved for that habitat may no longer suit the new environment," he said, adding that birdsong is an important part of people's connection with nature and should be preserved. Source: BBC

Scientists have discovered three previously unknown types of Helicobacter bacteria in pygmy sperm whales, offering new clues about the health of one of the ocean's most mysterious marine mammals. Pygmy sperm whales (Kogia breviceps) are among the least studied whale species because they spend most of their lives far offshore, travel in small groups and dive deep to hunt squid and fish. As they are rarely seen in the wild, much of what scientists know about them comes from whales that wash ashore. Researchers from Florida Atlantic University's Harbor Branch Oceanographic Institute and partner institutions reviewed more than two decades of whale stranding records and preserved tissue samples. Their findings, published in the Journal of Wildlife Diseases, identified three previously undocumented Helicobacter genotypes, named Kogia Helicobacter 1, 2 and 3. The discovery is the first confirmed evidence of these bacteria in pygmy sperm whales and could help scientists better understand the role bacterial infections play in the health of marine mammals. "Helicobacter bacteria are known to cause stomach-related illnesses in humans and other animals, including chronic inflammation, ulcers and even stomach cancer," said lead researcher Annie Page. "Finding new strains in a deep-diving whale species is an important scientific discovery." New bacteria identified Between 1999 and 2020, researchers examined 59 stranded pygmy sperm whales, conducting post-mortem examinations on about 80% of them. Four whales were found to have spiral-shaped bacteria in their stomach tissue. Further laboratory testing and DNA analysis confirmed that the bacteria belonged to three previously unknown Helicobacter genotypes. According to researcher Wendy Marks, two of the newly identified bacteria are genetically similar to Helicobacter species previously found in dolphins, porpoises and humans. The third belongs to a more distinct genetic group, suggesting that many unknown bacteria may still exist in the ocean. Signs of stomach disease All four whales carrying the bacteria also showed signs of digestive system disease, including stomach inflammation, ulcers, tissue scarring and parasitic worm infections. One whale also had inflammation in its intestine. Although researchers did not conclude that the bacteria caused the whales' deaths, they said the repeated presence of stomach damage suggests the infection may contribute to long-term health problems. Helicobacter bacteria were first identified in marine mammals in 2000 and have since been found in several whale and dolphin species. Infections have been linked to stomach ulcers, inflammation, reduced appetite and other digestive disorders. More research needed Scientists say it remains unclear how common these newly discovered bacteria are among pygmy sperm whales or how much they affect the animals' health. Because the species is rarely observed in the wild, further studies will be needed to determine whether the bacteria contribute to illness, strandings or broader population declines. Researchers said the discovery also highlights the importance of long-term marine mammal stranding programmes, which provide valuable opportunities to study species that are otherwise difficult to observe. The study involved scientists from Florida Atlantic University, the University of Florida, Colorado State University and Marine Mammal Pathology Services. Source: Science Daily

Scientists have identified the rare type of meteorite that is believed to have struck Earth 66 million years ago, triggering the mass extinction that wiped out about 75 percent of all species, including all non-avian dinosaurs. According to a new study published in Science Advances, the impactor was most likely a rare carbon-rich meteorite known as a CO chondrite, based on an analysis of nickel isotopes preserved in material left behind after the Cretaceous-Paleogene impact. The international research team included scientists from the University of British Columbia (UBC), as well as research institutions in Paris, Brussels and Vienna. Researchers said CO chondrites differ significantly from the meteorites commonly found on Earth because they contain much lower amounts of volatile elements such as carbon, zinc, water and especially sulfur. "CO chondrites are very different from the meteorites typically displayed in museums," said Dr. Philippe Claeys, a visiting professor at UBC and one of the study's researchers. The findings suggest that sulfur carried by the meteorite itself was probably not the main cause of the global environmental disaster that followed the impact. Instead, scientists believe vast amounts of fine dust and debris blasted into the atmosphere played the biggest role by blocking sunlight and disrupting Earth's climate. To identify the impactor, researchers conducted highly precise measurements of nickel isotopes in samples collected from a thin layer of clay found around the world. This layer was formed after the asteroid struck Earth and marks the boundary between the Cretaceous and Paleogene periods. Scientists said the work was particularly challenging because nearly the entire meteorite vaporized upon impact, leaving behind only tiny traces of its original material. Despite the limited evidence, the unique nickel isotope signature allowed researchers to identify the impactor as a rare CO chondrite. The meteorite's exact origin remains uncertain. Researchers believe it may have come either from the outer regions of the solar system or from the outer part of the asteroid belt near Jupiter. Carbonaceous chondrites make up only about five percent of meteorites recovered on Earth, while CO chondrites represent only a small fraction of that already rare group. They are considered among the oldest and most primitive materials formed during the early history of the solar system. "Being struck by such a rare object highlights just how unfortunate the dinosaurs were," Claeys said. Scientists estimate the asteroid measured between 10 and 15 kilometres in diameter and hit Earth at a speed of around 64,000 kilometres per hour. The impact created the massive Chicxulub crater, which is now buried beneath Mexico's Yucatán Peninsula. Researchers say the collision triggered global environmental changes that led to one of the most devastating mass extinctions in Earth's history. Source: Science Daily

Scientists have proposed a new explanation for what fuels the Yellowstone supervolcano, challenging the long-held belief that it is fed by a deep plume of molten rock rising from Earth’s interior. A new study published in the journal ‘Science’ suggests that Yellowstone’s magma is instead supplied by a broad underground flow of hot rock, described as a “mantle wind,” moving through the upper mantle beneath North America. Supervolcanoes are capable of producing the largest volcanic eruptions on Earth, releasing more than 1,000 cubic kilometres of magma, rock and ash. Such eruptions can have far-reaching effects on global climate, ecosystems and human societies, making it important for scientists to understand how these massive volcanic systems develop. Researchers from the Institute of Geology and Geophysics of the Chinese Academy of Sciences created a detailed three-dimensional model of western North America to study how the Earth's outer shell, known as the lithosphere, and the underlying mantle interact. Their findings suggest that the hot material feeding Yellowstone comes from the shallow asthenosphere, a softer layer beneath the lithosphere, rather than from a deep mantle plume. The study also challenges the traditional idea that supervolcanoes contain huge, long-lasting chambers of liquid magma beneath the surface. Instead, researchers say the magma is spread through vast regions of partially molten rock called "magma mush" systems. These thick, semi-solid zones extend across large sections of the lithosphere and may only produce smaller liquid-rich magma pockets shortly before an eruption. Yellowstone, located in the western United States, has experienced two supereruptions over the past 2.1 million years, making it one of the world’s best-studied supervolcanoes. Previous research had identified a large magma mush system beneath Yellowstone, but the source of the magma and the forces shaping it remained uncertain. According to the new model, the underground mantle wind was created by the long-term movement of the ancient Farallon Plate, whose remnants still lie deep beneath central and eastern North America. As this hot mantle material flows eastward beneath the continent, it is forced downward under the thick lithosphere. The resulting stretching causes pressure to drop, allowing rock to melt and form magma. The researchers also found that opposing forces beneath Yellowstone gradually pull apart the continental lithosphere, creating a southwest-sloping pathway that allows magma to rise and evolve over time. They say the model closely matches existing geological and geophysical observations from the Yellowstone region. The researchers believe their findings provide one of the clearest explanations yet of how giant magma systems develop beneath supervolcanoes. The study also offers a possible mechanism for maintaining the long-lived magma mush systems believed to exist beneath many of the world's supervolcanoes.

Scientists have identified a brain mechanism that links deep sleep with growth hormone release, helping explain how quality sleep supports muscle growth, fat metabolism and brain function. Researchers at the University of California, Berkeley, say the discovery sheds new light on why poor sleep can affect physical health and may eventually help develop treatments for sleep-related metabolic and neurological disorders. Deep sleep, particularly the non-REM stage, plays a crucial role in repairing the body, strengthening muscles, supporting bone growth and regulating fat storage. It is also important for normal growth during adolescence. Growth hormone, which is released mainly during sleep, is central to these processes. However, scientists have long been uncertain about exactly how sleep controls the hormone's release. In a study published in the journal ‘Cell’, researchers mapped brain circuits involved in growth hormone regulation and discovered a feedback system that helps maintain a balance between sleep and hormone production. “People know that growth hormone release is tightly related to sleep,” said lead author Xinlu Ding. “We are providing a basic circuit to work on in the future to develop different treatments.” The study found that specialised cells in the hypothalamus, a region deep within the brain, control growth hormone through two key chemical signals. One stimulates hormone release while the other suppresses it, allowing the body to regulate hormone levels throughout different stages of sleep. Researchers also found that once growth hormone is released, it activates another brain region called the locus coeruleus, which is involved in alertness, attention and thinking ability. According to the study, hormone levels rise differently during REM and non-REM sleep, helping maintain healthy body functions. The team also discovered a feedback loop in which growth hormone gradually promotes wakefulness as sleep continues. However, excessive activity in the same brain region can trigger sleepiness, creating a balance between sleep and alertness. “This balance is essential for growth, repair and metabolic health,” said study co-author Daniel Silverman. Scientists say the findings could have implications for conditions linked to poor sleep, including obesity, diabetes, heart disease, Parkinson’s disease and Alzheimer’s disease. Researchers also noted that growth hormone may benefit cognitive performance by supporting alertness and mental focus after waking up. “Growth hormone not only helps you build your muscle and bones and reduce your fat tissue, but may also have cognitive benefits,” Ding said. The study was conducted by researchers from UC Berkeley and Stanford University and was supported by the Howard Hughes Medical Institute and other research grants. Source: Science Daily

Researchers have discovered that a very small change at the atomic level can significantly alter how a metal behaves, opening new possibilities for advanced electronics and materials design. A team at the University of Minnesota Twin Cities found that carefully controlling the interaction between two materials at their interface can dramatically change the electronic properties of a metal. Their study, published in ‘Nature Communications’, shows that a process known as interfacial polarization can be used to tune the surface work function of ruthenium dioxide (RuO₂) by more than 1 electron volt. The change was achieved simply by adjusting the thickness of an ultra-thin film by just a few nanometres. Researchers said the finding challenges the long-held belief that polarization mainly occurs in insulating or ferroelectric materials, not metals. “We often think of polarization as something that belongs to insulators or ferroelectrics — not metals,” said Bharat Jalan. “Our work shows that, through careful interface design, you can stabilise polarization in a metallic system and use it to tune electronic properties.” The effect was found to depend strongly on thickness, with the most significant change occurring when the ruthenium dioxide layer reached around four nanometres — roughly the width of a DNA strand. At this scale, the metal shifts from a strained atomic structure to a more relaxed arrangement, leading to noticeable changes in its electronic behaviour. “This was surprising,” said Seung Gyo Jeong. “We expected subtle interface effects, but not such a large and controllable change in work function.” Researchers said the ability to observe and link tiny atomic movements with major electronic changes shows how interface engineering can be used to precisely control metallic materials. They added that the discovery could have future applications in electronics, catalytic systems and emerging quantum technologies. Source: Science Daily

Pigeons may rely on an unexpected body part to navigate over long distances: their liver, according to a new study that sheds light on one of nature’s long-standing mysteries. Scientists have long known that many animals use Earth’s magnetic field to help them find their way. Birds, fish and sea turtles are among the species believed to use this natural compass, but researchers have struggled for decades to understand exactly how the process works. Pigeons are particularly famous for their navigation skills. They can travel hundreds of miles in a single day and have been used by humans for thousands of years to carry messages and important information. Over the years, scientists have proposed several theories about how pigeons detect magnetic signals, including through special molecules in their eyes, their beaks or their inner ears. However, a new study points to a different possibility. Researchers led by scientists in Germany found strong magnetic signals in the birds’ livers, specifically in iron-rich immune cells that help break down old red blood cells and store iron. When scientists temporarily removed these immune cells from pigeons and then observed their flights, the birds struggled to find their way home, according to the study published in the journal Science. “The magnetic sense has remained a mystery for nearly a century,” said Martin Wikelski of the Max Planck Institute of Animal Behavior. Researchers believe the iron-containing cells may help pigeons detect Earth’s magnetic field and provide navigation information to the brain. The effect was most noticeable on cloudy days. Scientists said that under clear skies pigeons can also use the sun as a guide, but when sunlight is unavailable, their magnetic sensing system becomes more important. According to study co-author Christian Kurts of the University of Bonn, the findings suggest the liver cells may play a key role in helping birds maintain their sense of direction. Another researcher involved in the study, Clivia Lisowski, said the immune cells are located close to nerve fibers in the liver, which could allow magnetic information to be transmitted to the brain. Experts not involved in the research described the findings as intriguing. Albert Kao of the University of Massachusetts Boston said he would not have expected the liver to play such a role, but the explanation appeared plausible. The researchers believe similar mechanisms could exist in other birds and animals, including mice. However, outside experts caution that more studies are needed to confirm the theory and understand exactly how magnetic signals are processed by the brain. Scientists also noted that magnetic-sensitive immune cells have been found in other parts of pigeons' bodies, including the beak and spleen, suggesting navigation may involve multiple systems rather than a single mechanism. In an accompanying editorial, researchers argued that pigeons may use several methods to navigate depending on the situation, such as traveling long distances or locating a specific destination. Having more than one way to find their way home, they noted, could be a useful advantage for birds flying in difficult conditions.