By Gina Kolata Every so often a drug comes along that has the potential to change the world. Medical specialists say the latest to offer that possibility are the new drugs that treat obesity — Ozempic, Wegovy, Mounjaro and more that may soon be coming onto the market. It’s early, but nothing like these drugs has existed before. “Game changers,” said Jonathan Engel, a historian of medicine and health care policy at Baruch College in New York. Obesity affects nearly 42 percent of American adults, and yet, Dr. Engel said, “we have been powerless.” Research into potential medical treatments for the condition led to failures. Drug companies lost interest, with many executives thinking — like most doctors and members of the public — that obesity was a moral failing and not a chronic disease. While other drugs discovered in recent decades for diseases like cancer, heart disease and Alzheimer’s were found through a logical process that led to clear targets for drug designers, the path that led to the obesity drugs was not like that. In fact, much about the drugs remains shrouded in mystery. Researchers discovered by accident that exposing the brain to a natural hormone at levels never seen in nature elicited weight loss. They really don’t know why, or if the drugs may have any long-term side effects. “Everyone would like to say there must be some logical explanation or order in this that would allow predictions about what will work,” said Dr. David D’Alessio, chief of endocrinology at Duke, who consults for Eli Lilly among others. “So far there is not.” Although the drugs seem safe, obesity medicine specialists call for caution because — like drugs for high cholesterol levels or high blood pressure — the obesity drugs must be taken indefinitely or patients will regain the weight they lost. Dr. Susan Yanovski, a co-director of the office of obesity research at the National Institute of Diabetes and Digestive and Kidney Diseases, warned that patients would have to be monitored for rare but serious side effects, especially as scientists still don’t know why the drugs work. But, she added, obesity itself is associated with a long list of grave medical problems, including diabetes, liver disease, heart disease, cancers, sleep apnea and joint pain. “You have to keep in mind the serious diseases and increased mortality that people with obesity suffer from,” she said. © 2023 The New York Times Company

Keyword: Obesity
Link ID: 28875 - Posted: 08.19.2023

Saima May Sidik A protein involved in wound healing can improve learning and memory in ageing mice1. Platelet factor 4 (PF4) has long been known for its role in promoting blood clotting and sealing broken blood vessels. Now, researchers are wondering whether this signalling molecule could be used to treat age-related cognitive disorders such as Alzheimer’s disease. “The therapeutic possibilities are very exciting,” says geneticist and anti-ageing scientist David Sinclair at Harvard University in Boston, Massachusetts, who was not involved in the research. The study was published on 16 August in Nature. Young blood, old brains About a decade ago, scientists discovered that blood from young mice could restore youthful properties, including learning abilities, in older mice2,3. The idea captivated Saul Villeda, a neuroscientist at the University of California, San Francisco, and a co-author of the new study. He and his colleagues have since been trying to identify the components of blood that cause this rejuvenation. Several lines of evidence suggested that PF4 might be one of these components, including the fact that young mice have higher levels of this molecule in their blood than do older mice. Villeda and his colleagues tried injecting PF4 into aged mice without including other blood components. The researchers found that the ratios of various types of immune cell shifted to become more similar to what is typically seen in younger mice. Some immune cells also reverted to a more youthful pattern of gene expression. Although PF4 was not able to cross the blood–brain barrier, its effects on the immune system also led to changes in the brain, probably through indirect mechanisms. Old mice that received doses of PF4 showed decreases in damaging inflammation in the hippocampus — a part of the brain that’s particularly vulnerable to the effects of ageing. They also showed increases in the levels of molecules that promote synaptic plasticity (the capacity to alter the strength of connections between nerve cells). © 2023 Springer Nature Limited

Keyword: Development of the Brain
Link ID: 28874 - Posted: 08.19.2023

David Cox In June 2021, 32-year-old actor Kate Hyatt travelled to a farmhouse near Great Malvern in Worcerstershire for a plant medicine retreat that she hoped would improve her mental health after a difficult time during the pandemic lockdowns. While there, she is believed to have taken a substance called wachuma, or San Pedro cactus, a powerful hallucinogen used by Indigenous people in the Andes for thousands of years. But Hyatt did not experience relief; instead, her mental health worsened. Three months later, she described being in “some sort of psychotic break” and feeling as if her brain was going to explode. Later that autumn she took her own life. At the subsequent inquest, the coroner’s report linked her worsening symptoms to the hallucinogens she had consumed. Such tragedies represent the darker side of the psychedelics renaissance. These cases are often forgotten amid the feverish anticipation surrounding the therapeutic potential of these drugs, combined with exhaustive media coverage, the rapid rise of a billion-dollar industry – ranging from venture capital-backed startups to wellness retreats – and the hype around last year’s Netflix series How to Change Your Mind (based on Michael Pollan’s bestselling book). Yet without careful monitoring and scrutiny of who receives them, this class of drugs – which includes LSD, MDMA (commonly known as ecstasy or molly) and psilocybin (the active ingredient of magic mushrooms) – can be dangerous. There is evidence that they can destabilise vulnerable individuals who have experienced a previous psychotic episode or have a family history of psychosis. The substances are illegal to distribute and possess in the UK, although they are often obtained on the hidden market. Scientific researchers and biotechnology companies are able to use them in clinical trials only after obtaining a Home Office licence and applying extensive security arrangements. © 2023 Guardian News & Media Limited

Keyword: Depression; Drug Abuse
Link ID: 28873 - Posted: 08.19.2023

By Veronique Greenwood Floating languorously through forests and jungles of the Americas, longwing butterflies have many secrets. The 30-odd species in this group include many mimics. The wing markings on some distantly related species of longwings are so similar they inspired one Victorian naturalist to theorize that harmless species could mimic deadly ones to avoid predators. In the age of genomic sequencing, biologists have found other oddities in longwings. In a paper published last week in the Proceedings of the National Academy of Sciences, researchers report that female zebra longwings can see colors that males cannot, thanks to a gene on their sex chromosome. Understanding how it got there might shed light on how differences between sexes can evolve. Like primates, butterflies have a handful of proteins that are sensitive to certain wavelengths of light that, working together, produce the ability to distinguish colors. Curious about the zebra longwing’s vision, Adriana Briscoe, a professor at the University of California, Irvine, and an author of the new paper, asked a student to check the species’ genome for a well-known color vision gene. The gene, known as UVRh1, codes for a protein that is sensitive to ultraviolet light. To her surprise, it was nowhere to be found. Digging deeper, and drawing on genomic data from additional zebra longwings, Dr. Briscoe and her colleagues discovered that UVRh1 was there, but only in females. With lab experiments, they confirmed that females could see markings males couldn’t. They eventually pinpointed the gene in an unexpected place: the butterfly’s tiny sex chromosome. Sex chromosomes in butterflies are unstable, often shedding genes that are picked up by other chromosomes, or lost entirely, Dr. Briscoe said. That makes them a somewhat unusual place to keep something as important as a gene for color vision. © 2023 The New York Times Company

Keyword: Sexual Behavior; Vision
Link ID: 28872 - Posted: 08.19.2023

By Elizabeth Preston Some things need no translation. No matter what language you speak, you can probably recognize a fellow human who is cheering in triumph or swearing in anger. If you are a crocodile, you may recognize the sound of a young animal crying in distress, even if that animal is a totally different species — like, say, a human baby. That sound means you are close to a meal. In a study published Wednesday in Proceedings of the Royal Society B, researchers put speakers near crocodiles and played recordings of human, bonobo and chimpanzee infants. The crocodiles were attracted to the cries, especially shrieks that sounded more distressed. “That means that distress is something that is shared by species that are really, really distant,” said Nicolas Grimault, a bioacoustic research director at the French National Centre for Scientific Research and one of the paper’s authors. “You have some kind of emotional communication between crocodiles and humans.” These infant wails most likely drew crocodiles because they signaled an easy meal nearby, the authors say. But in some cases, the opposite may have been true: The crocs were trying to help. The animals in the study were Nile crocodiles, African predators that can reach up to 18 feet long. Understandably, the researchers kept their distance. They visited the reptiles at a Moroccan zoo and placed remote-controlled loudspeakers on the banks of outdoor ponds. The researchers played recordings of cries from those speakers while groups of up to 25 crocodiles were nearby. Some cries came from infant chimpanzees or bonobos calling to their mothers. Others were human babies, recorded either at bath time or in the doctor’s office during a vaccination. Nearly all of the recordings prompted some crocodiles to look or to move toward the speaker. When they heard the sounds of human babies getting shots, for example, almost half the crocodiles in a group responded. Dr. Grimault said the reptiles seemed most tempted by cries with a harsh quality that other studies have linked to distress in mammals. © 2023 The New York Times Company

Keyword: Hearing; Evolution
Link ID: 28871 - Posted: 08.09.2023

Jon Hamilton If you've ever had trouble finding your keys or remembering what you had for breakfast, you know that short-term memory is far from perfect. For people who've had a traumatic brain injury (TBI), though, recalling recent events or conversations can be a major struggle. "We have patients whose family cannot leave them alone at home because they will turn on the stove and forget to turn it off," says Dr. Ramon Diaz-Arrastia, who directs the Traumatic Brain Injury Clinical Research Center at the University of Pennsylvania. So Arrastia and a team of scientists have been testing a potential treatment. It involves delivering a pulse of electricity to the brain at just the right time. And it worked in a study of eight people with moderate or severe TBIs, the team reports in the journal Brain Stimulation. A precisely timed pulse to a brain area just behind the ear improved recall by about 20 percent and reduced the person's memory deficit by about half. If the results pan out in a larger study, the approach might improve the lives of many young people who survive a serious TBI, says Diaz-Arrastia, an author of the study and a professor of neurology at Penn. "In many cases, the reason they're unable to rejoin and fully participate in society is because of their memory problems," he says. "And they often have this disability that goes on for many, many decades." But the treatment is not for the timid. It requires patients to have electrodes surgically implanted in their brain. And scientists are still refining the system that delivers the electrical pulses. More than 1.5 million people in the U.S. sustain a TBI each year. Common causes include falls, motor vehicle accidents, assaults, contact sports, and gunshots. © 2023 npr

Keyword: Brain Injury/Concussion
Link ID: 28870 - Posted: 08.09.2023

By Alla Katsnelson Our understanding of animal minds is undergoing a remarkable transformation. Just three decades ago, the idea that a broad array of creatures have individual personalities was highly suspect in the eyes of serious animal scientists — as were such seemingly fanciful notions as fish feeling pain, bees appreciating playtime and cockatoos having culture. Today, though, scientists are rethinking the very definition of what it means to be sentient and seeing capacity for complex cognition and subjective experience in a great variety of creatures — even if their inner worlds differ greatly from our own. Such discoveries are thrilling, but they probably wouldn’t have surprised Charles Henry Turner, who died a century ago, in 1923. An American zoologist and comparative psychologist, he was one of the first scientists to systematically probe complex cognition in animals considered least likely to possess it. Turner primarily studied arthropods such as spiders and bees, closely observing them and setting up trailblazing experiments that hinted at cognitive abilities more complex than most scientists at the time suspected. Turner also explored differences in how individuals within a species behaved — a precursor of research today on what some scientists refer to as personality. Most of Turner’s contemporaries believed that “lowly” critters such as insects and spiders were tiny automatons, preprogrammed to perform well-defined functions. “Turner was one of the first, and you might say should be given the lion’s share of credit, for changing that perception,” says Charles Abramson, a comparative psychologist at Oklahoma State University in Stillwater who has done extensive biographical research on Turner and has been petitioning the US Postal Service for years to issue a stamp commemorating him. Turner also challenged the views that animals lacked the capacity for intelligent problem-solving and that they behaved based on instinct or, at best, learned associations, and that individual differences were just noisy data. But just as the scientific establishment of the time lacked the imagination to believe that animals other than human beings can have complex intelligence and subjectivity of experience, it also lacked the collective imagination to envision Turner, a Black scientist, as an equal among them. The hundredth anniversary of Turner’s death offers an opportunity to consider what we may have missed out on by their oversight. © 2023 Annual Reviews

Keyword: Learning & Memory; Evolution
Link ID: 28869 - Posted: 08.09.2023

By Laurie McGinley and David Ovalle The weight-loss drug Wegovy reduced the risk of strokes, heart attacks and other cardiovascular problems by 20 percent among overweight people with a history of heart disease, its manufacturer said Tuesday, results that could increase demand and bolster the case for insurance coverage for the medication. The better-than-expected result was announced by Danish pharmaceutical giant Novo Nordisk in a news release. Experts said the results of the trial, called Select, demonstrate that a new crop of drugs commonly used for weight loss, such as Wegovy, can provide important health benefits, not just cosmetic ones. Obesity should be treated as a serious illness given its connection to other problems such as heart disease, specialists said. Still, private insurers have been slow to cover Wegovy, and Medicare is barred from paying for weight-loss medications. With Wegovy costing more than $1,300 a month, the lack of insurance coverage has put the drug out of reach for many people. The study is important because it could shift perceptions of Wegovy and similar drugs, said Andres J. Acosta, an assistant professor of medicine and a consultant in gastroenterology and hepatology at the Mayo Clinic. Previously, the medications were highlighted for their cosmetic results. “It’s a new era,” Acosta said. “It matters because if you lose weight, your risk of dying is reduced.” The data from the highly anticipated trial have not been published. The results released Tuesday were top-line findings, and the company said it would release detailed results at a conference later this year. Steven Nissen, a Cleveland Clinic cardiologist, noted that while Tuesday’s announcement is promising, he wants to see the full results. “We have to be cautious until we actually see the peer-reviewed publication,” said Nissen, who is leading a similar trial involving Eli Lilly’s Mounjaro, a diabetes drug commonly used for weight loss.

Keyword: Obesity
Link ID: 28868 - Posted: 08.09.2023

By Pam Belluck The Food and Drug Administration on Friday approved the first pill for postpartum depression, a milestone considered likely to increase recognition and treatment of a debilitating condition that afflicts about a half-million women in the United States every year. Clinical trial data show the pill works quickly, beginning to ease depression in as little as three days, significantly faster than general antidepressants, which can take two weeks or longer to have an effect. That — along with the fact that it is taken for just two weeks, not for months — may encourage more patients to accept treatment, maternal mental health experts said. The most significant aspect of the approval may not be the features of the drug, but that it is explicitly designated for postpartum depression. Several doctors and other experts said that while there were other antidepressants that are effective in treating the condition, the availability of one specifically shown to address it could help reduce the stigma of postpartum depression by underscoring that it has biological underpinnings and is not something women should blame themselves for. The hope is that it will encourage more women to seek help and prompt more obstetricians and family doctors to screen for symptoms and suggest counseling or treatment. “This is a patient population that just so often falls through the cracks,” said Dr. Ruta Nunacs, a psychiatrist with the Center for Women’s Mental Health at Massachusetts General Hospital. “When women are told, ‘You have postpartum depression,’ it’s embarrassing, it is demeaning, it makes them feel like a bad mom.” She added, “There’s also a lot of stigma about taking antidepressant medication, so that might make this treatment more appealing because it’s really a treatment specific for postpartum depression.” © 2023 The New York Times Company

Keyword: Depression; Sexual Behavior
Link ID: 28867 - Posted: 08.05.2023

By Aara'L Yarber When the pandemic began, losing your sense of smell was considered a key indicator of covid-19, and the condition affected about half of those who tested positive for the coronavirus. However, a new study reveals that the chance of smell loss from the latest omicron variants has dropped dramatically since the early days of the pandemic. “So now, three people out of 100 getting covid presumably may lose their sense of smell, which is far, far less than it was before,” said study leader Evan Reiter, the medical director of Virginia Commonwealth University Health’s Smell and Taste Disorders Center. The findings, published in the journal Otolaryngology — Head and Neck Surgery, mean that losing smell and, by association, your sense of taste is no longer a reliable sign that someone has a covid infection, Reiter said. Advertisement “Now, the chance of you having [smell loss from] covid as opposed to another virus, like different cold and flu bugs, is about the same,” he said. Although it is unclear why the frequency of smell loss has decreased over time, vaccinations and preexisting immunity could be playing a role, the researchers said. Doctors have had difficulty explaining the cause of smell loss, but some research suggests it is due to covid triggering a prolonged immune assault on olfactory nerve cells. These cells sit at the top of the nasal cavity and help send smell signals from the nose to the brain. It is possible that over time this attack causes a decline in the number of olfactory cells. But if you’ve already been infected or vaccinated, the time the virus has to inflict this kind of damage is dramatically reduced, said Benjamin tenOever, a professor of microbiology and medicine at New York University who was not involved in the study.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 28866 - Posted: 08.05.2023

By Gina Kolata A national survey released on Friday by KFF, a nonprofit organization focused on health policy, has found that Americans long for safe and effective drugs for weight loss. But the more they learn about new drugs like Wegovy that are transforming obesity treatment, the more their enthusiasm fades. The survey found that 59 percent of people who were trying to lose weight said they were interested in taking a safe and effective drug. But only 23 percent remained interested when asked if they would take such a drug if it had to be injected. And just 16 percent were still interested if their insurance would not pay for the drug. The list price of the drugs is about $1,300 a month. When they heard they would regain their lost weight it they stopped taking the drug, interest declined to 14 percent. “People always want that magic pill,” said Ashley Kirzinger, director of survey methodology at KFF. “There is no magic.” The survey was conducted in July online and by telephone with a representative sample of 1,327 U.S. adults. That’s the median weight loss experienced by people who take Wegovy, a drug from Novo Nordisk. The new drugs are the first truly effective obesity medicines. They act by stemming people’s appetites and cravings for food. Many patients started by taking Ozempic, a diabetes drug also by Novo Nordisk that led to weight loss as a side effect. But many more patients are asking for Wegovy, which is approved for obesity. Mounjaro, made by Eli Lilly and approved for treating diabetes, is expected to be approved soon for obesity. People taking it lose a median of 20 percent of their body weight. Obesity is a chronic disease that can result in diabetes and other conditions like high blood pressure, heart disease, sleep apnea and joint problems. But it was so difficult to treat obesity that many doctors and patients had all but given up. © 2023 The New York Times Company

Keyword: Obesity
Link ID: 28865 - Posted: 08.05.2023

By Simon Makin Rats are extremely playful creatures. They love playing chase, and they literally jump for joy when tickled. Central to this playfulness, a new study finds, are cells in a specific region of rats’ brains. Neurons in the periaqueductal gray, or PAG, are active in rats during different kinds of play, scientists report July 28 in Neuron. And blocking the activity of those neurons makes the rodents much less playful. The results give insight into a poorly understood behavior, particularly in terms of how play is controlled in the brain. “There are prejudices that it’s childish and not important, but play is an underrated behavior,” says Michael Brecht, a neuroscientist at Humboldt University in Berlin. Scientists think play helps animals develop resilience. Some even relate it to optimal functioning. “When you’re playing, you’re being your most creative, thoughtful, interactive self,” says Jeffrey Burgdorf, a neuroscientist at Northwestern University in Evanston, Ill., who was not involved in the new study. This is the opposite of depressive states, and Burgdorf’s own research aims to turn understanding the neuroscience of play into new therapies for mood disorders. For the new study, Brecht and colleagues got rats used to lab life and being tickled and played with in a game of chase-the-hand. When rats play, they squeal with glee at a frequency of 50 kilohertz, which humans can’t hear. The researchers recorded these ultrasonic giggles as a way of measuring when the rats were having fun. To explore how a specific brain region in rats might relate to their well-documented play behavior, researchers tickled rats on their bellies and backs and played chase-the-hand. Rats also played together, chasing and play-fighting. Ultrasonic giggles, processed to make them audible to humans, coordinate social play and show that the rats are having fun. © Society for Science & the Public 2000–2023.

Keyword: Emotions; Evolution
Link ID: 28864 - Posted: 08.02.2023

By Claudia López Lloreda When someone loses a hand or leg, they don’t just lose the ability to grab objects or walk—they lose the ability to touch and sense their surroundings. Prosthetics can restore some motor control, but they typically can’t restore sensation. Now, a preliminary studyposted to the preprint server bioRxiv this month—shows that by mimicking the activity of nerves, a device implanted in the remaining part of the leg helps amputees “feel” as they walk, allowing them to move faster and with greater confidence. “It's a really elegant study,” says Jacob George, neuroengineer at the University of Utah who was not involved with the research. Because the experiments go from a computational model to an animal model and then, finally humans, he says, “This work is really impactful, because it's one of the first studies that's done in a holistic way.” Patients with prosthetics often have a hard time adapting. One big issue is that they can’t accurately control the device because they can’t feel the pressure that they’re exerting on an object. Hand and arm amputees, for example, are more prone to drop or break things. As a result, some amputees refuse to use such prosthetics. In the past few years, researchers have been working on prosthetic limbs that provide more natural sensory feedback both to help control the device better and give them back a sense of agency over their robotic limb. In a critical study in 2019, George and his team showed that so-called biomimetic feedback, sensory information that aims to resemble the natural signals that occur with touch, allowed a patient who’d lost his hand to more precisely grip fragile objects such as eggs and grapes. But such studies have been limited to single patients. They’ve also left many questions unanswered about how exactly this feedback helps with motor control and improves the use of the prosthetic. So in the new work, researchers used a computer model that re-creates how nerves in the foot respond to different inputs, such as feeling pressure. The goal was to create natural patterns of neural activity that might occur when sensing something with the foot or walking. © 2023 American Association for the Advancement of Science.

Keyword: Pain & Touch; Robotics
Link ID: 28863 - Posted: 08.02.2023

McKenzie Prillaman It’s rare to find a product so successful that its makers stop advertising it. But that’s what happened to the weight-loss drug Wegovy in May. In the United States, where prescription drugs can be advertised, developer Novo Nordisk pulled its television adverts because it couldn’t keep up with demand. The injectable medication, called semaglutide, works by imitating a hormone that curbs appetite and was approved as an obesity treatment by the US Food and Drug Administration (FDA) in 2021. In a study, participants who took semaglutide for over a year lost more than twice as much body weight on average — almost 16% — as did people taking an older weight-loss drug that mimics the same hormone1. Semaglutide’s approval for treatment of weight loss came four years after the drug was approved for type 2 diabetes under the trade name Ozempic, also made by Novo Nordisk, based in Bagsværd, Denmark. Demand for Ozempic has skyrocketed as physicians prescribe it for weight loss outside its approved use. Now, even more-potent medications for obesity are on the way. The drug tirzepatide, which is FDA-approved for type 2 diabetes under the name Mounjaro and made by Eli Lilly in Indianapolis, Indiana, imitates two hunger-related hormones. And the company’s drug retatrutide, which mimics three hormones, showed promising results for weight loss in its mid-stage clinical trial, announced at a conference in June. Neither of these newcomers has been approved for obesity. But treating the condition is more urgent than ever. Obesity rates have tripled in the past 50 years, and carrying significant extra weight often brings a heightened risk of other health complications, including type 2 diabetes, heart disease and some cancers. It can also impede quality of life in other ways, such as limiting a person’s range of movement or resulting in feelings of shame because of weight stigma. With this wave of drugs comes a fresh set of questions for researchers. “We are currently in such a dynamic phase of these transformative developments,” says physician-scientist Matthias Tschöp, chief executive of Helmholtz Munich, a research centre in Germany. “We’re still overwhelmed with curiosity.” © 2023 Springer Nature Limited

Keyword: Obesity
Link ID: 28862 - Posted: 08.02.2023

by Brendan Borrell The New York State Psychiatric Institute in New York City is undergoing an audit and a change in leadership following a suicide that occurred during one of its clinical trials. Autism researcher Jeremy Veenstra-VanderWeele has abruptly taken the helm as the interim executive director of the institute and chair of the Columbia University psychiatry department, replacing Helen Blair Simpson, Spectrum has learned. The New York State Psychiatric Institute is part of the New York State Office of Mental Health, but it shares buildings and staff with Columbia University and the university’s hospital. The Office of Mental Health is currently conducting an audit of the institute, according to Carla Cantor, the institute’s director of communications. The audit and turnover in leadership comes after the halting of a series of clinical trials conducted by Columbia psychiatrist Bret Rutherford, which tested whether the drug levodopa — typically used to treat Parkinson’s disease — could improve mood and mobility in adults with depression. During a double-blind study that began in 2019, a participant in the placebo group died by suicide. That study was suspended prior to completion, according to an update posted on ClinicalTrials.gov in 2022. Two published reports based on Rutherford’s pilot studies have since been retracted, as Spectrum has previously reported. The National Institute of Mental Health has terminated Rutherford’s trials and did not renew funding of his research grant or K24 Midcareer Award. Former members of Rutherford’s laboratory describe it as a high-pressure environment that often put publications ahead of study participants. “Research is important, but not more so than the lives of those who participate in it,” says Kaleigh O’Boyle, who served as clinical research coordinator there from 2018 to 2020. © 2023 Simons Foundation

Keyword: Depression; Parkinsons
Link ID: 28861 - Posted: 08.02.2023

By Yasemin Saplakoglu On warm summer nights, green lacewings flutter around bright lanterns in backyards and at campsites. The insects, with their veil-like wings, are easily distracted from their natural preoccupation with sipping on flower nectar, avoiding predatory bats and reproducing. Small clutches of the eggs they lay hang from long stalks on the underside of leaves and sway like fairy lights in the wind. The dangling ensembles of eggs are beautiful but also practical: They keep the hatching larvae from immediately eating their unhatched siblings. With sickle-like jaws that pierce their prey and suck them dry, lacewing larvae are “vicious,” said James Truman, a professor emeritus of development, cell and molecular biology at the University of Washington. “It’s like ‘Beauty and the Beast’ in one animal.” This Jekyll-and-Hyde dichotomy is made possible by metamorphosis, the phenomenon best known for transforming caterpillars into butterflies. In its most extreme version, complete metamorphosis, the juvenile and adult forms look and act like totally different species. Metamorphosis is not an exception in the animal kingdom; it’s almost a rule. More than 80% of the known animal species today, mainly insects, amphibians and marine invertebrates, undergo some form of metamorphosis or have complex, multistage life cycles. The process of metamorphosis presents many mysteries, but some of the most deeply puzzling ones center on the nervous system. At the center of this phenomenon is the brain, which must code for not one but multiple different identities. After all, the life of a flying, mate-seeking insect is very different from the life of a hungry caterpillar. For the past half-century, researchers have probed the question of how a network of neurons that encodes one identity — that of a hungry caterpillar or a murderous lacewing larva — shifts to encode an adult identity that encompasses a completely different set of behaviors and needs. Truman and his team have now learned how much metamorphosis reshuffles parts of the brain. In a recent study published in the journal eLife, they traced dozens of neurons in the brains of fruit flies going through metamorphosis. They found that, unlike the tormented protagonist of Franz Kafka’s short story “The Metamorphosis,” who awakes one day as a monstrous insect, adult insects likely can’t remember much of their larval life. Although many of the larval neurons in the study endured, the part of the insect brain that Truman’s group examined was dramatically rewired. That overhaul of neural connections mirrored a similarly dramatic shift in the behavior of the insects as they changed from crawling, hungry larvae to flying, mate-seeking adults. All Rights Reserved © 2023

Keyword: Learning & Memory
Link ID: 28860 - Posted: 07.27.2023

Liam Drew Scientific advances are rapidly making science-fiction concepts such as mind-reading a reality — and raising thorny questions for ethicists, who are considering how to regulate brain-reading techniques to protect human rights such as privacy. On 13 July, neuroscientists, ethicists and government ministers discussed the topic at a Paris meeting organized by UNESCO, the United Nations scientific and cultural agency. Delegates plotted the next steps in governing such ‘neurotechnologies’ — techniques and devices that directly interact with the brain to monitor or change its activity. The technologies often use electrical or imaging techniques, and run the gamut from medically approved devices, such as brain implants for treating Parkinson’s disease, to commercial products such as wearables used in virtual reality (VR) to gather brain data or to allow users to control software. How to regulate neurotechnology “is not a technological discussion — it’s a societal one, it’s a legal one”, Gabriela Ramos, UNESCO’s assistant director-general for social and human sciences, told the meeting. Advances in neurotechnology include a neuroimaging technique that can decode the contents of people’s thoughts, and implanted brain–computer interfaces (BCIs) that can convert people’s thoughts of handwriting into text1. The field is growing fast — UNESCO’s latest report on neurotechnology, released at the meeting, showed that, worldwide, the number of neurotechnology-related patents filed annually doubled between 2015 and 2020. Investment rose 22-fold between 2010 and 2020, the report says, and neurotechnology is now a US$33-billion industry. One area in need of regulation is the potential for neurotechnologies to be used for profiling individuals and the Orwellian idea of manipulating people’s thoughts and behaviour. Mass-market brain-monitoring devices would be a powerful addition to a digital world in which corporate and political actors already use personal data for political or commercial gain, says Nita Farahany, an ethicist at Duke University in Durham, North Carolina, who attended the meeting. © 2023 Springer Nature Limited

Keyword: Brain imaging
Link ID: 28859 - Posted: 07.27.2023

By Tanvi Dutta Gupta The Arctic Ocean is a noisy place. Creatures of the deep have learned to live with the cacophony of creaking ice sheets and breaking icebergs, but humanmade sources of noise from ships and oil and gas infrastructure are altering that natural submarine soundscape. Now, a research team has found that even subtle underwater noise pollution can cause narwhals to make shallower dives and cut their hunts short. The research, published today in Science Advances, uncovers “some really great information on a species we know very little about,” says Ari Friedlaender, an ocean ecologist at the University of California, Santa Cruz, not involved in the study. Knowing how the whales react to these noises could help conservationists “act proactively” to protect the animals in their Arctic home where warming waters already threaten their lifestyles. Narwhals—with their long, unicornlike horns extending from their faces—live in one of the most extreme environments in the world, explains Outi Tervo, an ecologist at the Greenland Institute of Natural Resources and the study’s first author. Each narwhal returns in summer to the same small fjord where it was born in order to feed on fish, squid, and shrimp. As humans increasingly encroach on Arctic waters, though, scientists, conservationists, and Inuit communities have worried about how development and ship traffic will affect the whales. Many of Greenland’s Inuit communities rely on the narwhals as a culturally important food source. When Greenland’s government started to auction new permits for offshore oil exploration in 2011, Tervo and colleagues decided to examine whether the noise pollution associated with such development affected narwhals. For instance, boats exploring the sea floor tow instruments called airguns, which blast air a few meters below the vessels to sonically suss out the presence of cavities that may contain oil and gas. Those pulses can be the “loudest sound put in the ocean by humans,” says study co-author Susanna Blackwell, a biologist with Greeneridge Sciences.

Keyword: Animal Communication; Hearing
Link ID: 28858 - Posted: 07.27.2023

by Giorgia Guglielmi Mice with a mutation that boosts the activity of the autism-linked protein UBE3A show an array of behaviors reminiscent of the condition, a new study finds. The behaviors differ depending on whether the animals inherit the mutation from their mother or their father, the work also reveals. The results add to mounting evidence that hyperactive UBE3A leads to autism. Duplications of the chromosomal region that includes UBE3A have been associated with autism, whereas deletions and mutations that destroy the gene’s function are known to cause Angelman syndrome, which is characterized by developmental delay, seizures, lack of speech, a cheerful demeanor and, often, autism. “UBE3A is on a lot of clinicians’ radar because it is well known to be causative for Angelman syndrome when mutated or deleted,” says lead investigator Mark Zylka, professor of cell biology and physiology at the University of North Carolina at Chapel Hill. “What our study shows is that just because you have a mutation in UBE3A, it doesn’t mean that it’s going to be Angelman syndrome.” In the cell, UBE3A is involved in the degradation of proteins, and “gain-of-function” mutations — which send the UBE3A protein into overdrive — result in enhanced degradation of its targets, including UBE3A itself. Studying the effects of these mutations could provide insight into how they affect brain development and suggest targets for therapies, says study investigator Jason Yi, assistant professor of neuroscience at Washington University in St. Louis, Missouri. Gain-of-function mutations in UBE3A can disrupt early brain development and may contribute to neurodevelopmental conditions that are distinct from Angelman syndrome, Yi and Zylka have shown in previous studies. One of the mutations they analyzed had been found in an autistic child, so the team used CRISPR to create mice with this mutation. © 2023 Simons Foundation

Keyword: Autism
Link ID: 28857 - Posted: 07.27.2023

Lilly Tozer A study that followed thousands of people over 25 years has identified proteins linked to the development of dementia if their levels are unbalanced during middle age. The findings, published in Science Translational Medicine on 19 July1, could contribute to the development of new diagnostic tests, or even treatments, for dementia-causing diseases. Most of the proteins have functions unrelated to the brain. “We’re seeing so much involvement of the peripheral biology decades before the typical onset of dementia,” says study author Keenan Walker, a neuroscientist at the US National Institute on Aging in Bethesda, Maryland. Equipped with blood samples from more than 10,000 participants, Walker and his colleagues questioned whether they could find predictors of dementia years before its onset by looking at a person’s proteome — the collection of all the proteins expressed throughout the body. They searched for any signs of dysregulation — when proteins are at levels much higher or lower than normal. The samples were collected as part of an ongoing study that began in 1987. Participants returned for examination six times over three decades, and during this time, around 1 in 5 of them developed dementia. The researchers found 32 proteins that, if dysregulated in people aged 45 to 60, were strongly associated with an elevated chance of developing dementia in later life. It is unclear how exactly these proteins might be involved in the disease, but the link is “highly unlikely to be due to just chance alone”, says Walker © 2023 Springer Nature Limited

Keyword: Alzheimers
Link ID: 28856 - Posted: 07.22.2023