Latest news with #mice
Medscape
6 days ago
- Health
- Medscape
Watching Peers Eat Can Trigger Overeating, Says Mouse Study
TOPLINE: Even in the absence of hunger, mice increased their sucrose diet intake after observing their peers eat. This effect was abolished by the inhibition of dopamine receptors. METHODOLOGY: Previous studies in humans have shown a significant association between external eating behaviors and watching eating shows, but this has not been confirmed in a mouse model. This study examined whether satiated mice, despite not being hungry, increased their food intake when watching a peer engage in binge-like eating behavior. A total of 14 male mice were divided into two groups: One group was either fed or fasted overnight before testing, and the other group was always fed before testing. Mice were paired according to genetic and parental information and placed in separate but adjacent chambers for interaction without physical contact. Food intake was recorded hourly for 4 hours across different days, using chow, high-fat, and sucrose diets. In a follow-up experiment, the group of mice that was always fed before testing received intraperitoneal injections of saline, a D1 dopamine receptor inhibitor, or a D2 dopamine receptor inhibitor prior to testing. TAKEAWAY: Satiated mice increased their sucrose diet intake during the first hour while watching peers that had fasted eat, with significant increases noted in both the initial and repeated tests (P = .0043 and P = .0154, respectively). No significant increase in chow or high-fat diet intake was observed when satiated mice watched peers that had fasted consume the diets. The increase in sucrose intake persisted after saline injection (P = .0057) but was abolished after the administration of the D1 or D2 dopamine receptor inhibitors. IN PRACTICE: 'Establishing this animal model provides a foundation for future studies on the neurobiological mechanisms underlying cognitive-driven food intake and may contribute to the development of targeted therapeutic strategies for obesity,' the authors of the study wrote. 'This animal model opens the door to developing new treatments that target the brain's reward system to help prevent or reduce overeating,' Yong Xu, PhD, MD, professor and associate director for Basic Sciences at the Children's Nutrition Research Center, Baylor College of Medicine, Houston, said in a news release. 'It also supports public health efforts that aim to limit the influence of visual food cues in media and social settings, which could help people better manage their weight and eating habits.' SOURCE: The study was led by Xu Xu, MD, Baylor College of Medicine, Texas Children's Hospital, Houston. It was presented on June 14, 2025, at the ENDO 2025: The Endocrine Society Annual Meeting in San Francisco. LIMITATIONS: No limitations were discussed in the abstract. DISCLOSURES: No disclosures or conflict of interest statements were provided. This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.
Yahoo
13-07-2025
- Science
- Yahoo
Experts deploy helicopters carrying over 500 tons of poison to eradicate dangerous island threat: 'A roll of the dice'
An invasive population of mice is wreaking havoc on Marion Island, a small island off the southern coast of South Africa, reported. The damage they've done to local seabird populations has grown so extreme that officials are looking to eradicate all of the mice in one fell swoop using an innovative method — rodenticide-laced pellets. Mice first arrived on the island two centuries ago, via sealing vessels, and they've been relatively minor pests for much of their time there. However, reported that a number of factors — namely, warmer temperatures that extend their breeding cycles — have created the perfect storm for an enormous mouse population. That population is, of course, hungry. The mice seek food in the form of bird eggs and even the birds themselves. Now, grisly sights can be found around the island, as mice gnaw for hours at a time on nesting albatross. The birds, who never evolved a defense mechanism against land predators, simply sit in place until they bleed out or succumb to infection. "These mice, for the first time last year, were found to be feeding on adult Wandering Albatrosses," said Mark Anderson, CEO of nonprofit BirdLife South Africa, per "Mice just climb onto them and slowly eat them until they succumb." According to warmer waters have also driven fish deeper and farther south, meaning adult birds need to travel further for food and return to their nests more exhausted, unable to endure the attacks. Additionally, climate-intensified storms have been wiping away nests with extreme weather. "Combined with the mouse attacks, these pressures make every breeding season a roll of the dice," explained. Marion is home to approximately 25% of the world's wandering albatross and 29 seabird species overall. However, given the severe threat posed by the mice, 19 of those species are now facing local extinction. This poses a significant risk to the entire marine ecosystem of Marion and beyond. According to a study published in the Ecological Society of America, seabirds play an integral role in their food webs, enriching plant and coral health through their roles as both predators and prey. How concerned are you about the plastic waste in our oceans? Extremely I'm pretty concerned A little Not much Click your choice to see results and speak your mind. Their guano, or dung, fertilizes the oceans with nitrogen and phosphorus, boosting plankton and fish populations. Without these stocks, the entire food web would suffer. Generally, any time that an invasive species wipes out a native plant or animal species, it risks throwing the entire ecosystem off balance. This jeopardizes the natural functions of that environment, including air and water filtration, food production, carbon sequestration, and disease control. It can also cost billions, or even trillions, of dollars to local economies. To address the issue, an initiative called the Mouse-Free Marion Project is looking to wipe out the island's mice all at once, leaving no chance for the species' recovery. The plan? Using helicopters to distribute 600 tons of rodenticide-laced cereal pellets. It may sound drastic, but conservationists argue that drastic is now the only possible approach. "We have to get rid of every last mouse," Anderson explained to "If there were a male and female remaining, they could breed and eventually get back to where we are now." Currently, the program is fundraising, as it comes with a hefty $29 million price tag, and hopes to deploy its "bombs" in 2027. Join our free newsletter for good news and useful tips, and don't miss this cool list of easy ways to help yourself while helping the planet.
Yahoo
13-07-2025
- Health
- Yahoo
Researchers make disturbing discovery about health risks lurking in common products: 'Highlights the critical need for further exploration'
A new study may help to unpack possible effects of microplastic pollution, including from biodegradable alternatives, on metabolism and gut bacteria. The findings suggest some concerning signs that demand further exploration into long-term health risks that could be linked to microplastic exposure and ingestion, such as the potential for gut inflammation and microbiome disruption. Polylactic acid, or PLA, is a bioplastic commonly marketed as biodegradable or compostable, and it's often used in food packaging. Made from fermented plant starch rather than fossil fuels, when broken down under the right conditions, it can degrade into lactic acid, generally understood as safe. However, PLA can also break down incompletely, resulting in some divided opinions on the material and its potential health and environmental advantages over traditional plastics. Researchers from China say their new findings indicate that PLA microplastics can break down into nanoparticles inside the body and potentially trigger a range of harmful biological responses. In their study, published in June online by the Journal of Hazardous Materials, mice were orally exposed to a daily dose of PLA microplastics. Researchers noted that "the particles retrieved from mouse feces exhibited a significant size reduction, breaking down from the micrometer scale to the nanometer scale." Short-term oral exposure appeared to impact gut microbiota and induce inflammation, while longer-term exposure seemed to cause persistent changes, including to the metabolism. The co-authors of this new study say the research "highlights the critical need for further exploration into the long-term health risks of microplastic exposure," even when it comes to materials manufactured to be biodegradable or compostable. While microplastic pollution has been studied in marine animals and environments, as well as the occasional tortoise or donkey, this study focuses on the potential for serious risks to human health and looks at PLA microplastics in particular. In 2019, a research team, with support from the World Wide Fund, estimated that people may consume up to 5 grams of microplastics per week — roughly the weight of a credit card. Some studies have also investigated possible links between microplastic exposure and chronic illnesses, such as endometriosis, though these studies have largely looked at traditional plastics. When PLA microplastics are used, it tends to be because of their eco-friendly image as a biodegradable alternative to traditional plastic types. Leveraging safe, sustainable alternatives to fossil fuel-based products is critical, but this study shows that bioplastics may still pose health threats inside the body, meriting further investigation. The researchers suggest that nanoparticles resulting from PLA breakdown could disrupt gut bacteria and contribute to inflammation, which has been linked to a range of illnesses from liver disease to neurodegenerative disorders. While more research is needed to provide a complete and thorough understanding of the potential impacts of microplastics — including from bioplastics — on our well-being, this study points toward the possibility that reducing their use could come with some health benefits. As more experts are suggesting, while we don't yet have a full picture of microplastic hazards, we may have enough information to warrant making some changes now. Do you worry about air pollution in and around your home? Yes — always Yes — often Yes — sometimes No — never Click your choice to see results and speak your mind. Steps like cutting back on single-use plastic cutlery and straws at restaurants, opting for non-plastic reusable containers and shopping bags, and minimizing plastic-packaged food may help reduce personal exposure and the amount of plastic waste in the world. On a broader level, stronger regulations, corporate accountability, and funding for more research are all critical to curbing plastic pollution and protecting public health. Encouragingly, studies like this are pushing the conversation forward, showing that biodegradable may not always mean completely harmless. Join our free newsletter for good news and useful tips, and don't miss this cool list of easy ways to help yourself while helping the planet.
The Independent
07-07-2025
- Health
- The Independent
How mice are helping detect early signs of Parkinson's
Chinese scientists have identified subtle new early signs of Parkinson's disease in mice, potentially enabling much earlier diagnosis in humans. Researchers at the Chinese Academy of Sciences found that behaviours such as rearing, walking, and hunching in mice are linked to Parkinson's and the loss of specific midbrain dopamine neurons. The study revealed that reductions in rearing and hunching correlate directly with the loss of dopamine neurons in the substantia nigra pars compacta (SNc), a midbrain region. An advanced artificial intelligence behaviour analysis system was employed to meticulously examine the movements of mouse models with dopamine neuron depletion. These findings underscore the potential for monitoring such subtle behaviours as early markers to track Parkinson's progression and improve treatment strategies.
The Independent
07-07-2025
- Health
- The Independent
Breakthrough study finds subtle new early symptoms of Parkinson's to watch out for
Chinese scientists have discovered subtle new earlier signs of Parkinson's in mice, an advance that may help diagnose the debilitating condition much sooner in humans. Researchers from the Chinese Academy of Sciences found that behaviours such as rearing, walking, and hunching in mice, associated with the loss of a specific type of midbrain dopamine (DA) neurons, are linked to Parkinson's disease. The earliest known signs of Parkinson's can include pain, anxiety, balance issues, stiffness, loss of smell, sleep problems and depression. Other signs like tremors, handwriting changes, and diminished facial expressions, appear later as the disease progresses. Gradually, patients may experience severe movement issues, highlighting the importance of early diagnosis and treatment for the condition. Until now, research has mostly focused on the functions of the DA neurons in mood regulation and reward mechanisms. These nerve cells are located in the midbrain regions substantia nigra pars compacta (SNc) and the ventral tegmental area (VTA), are essential for regulating movement, emotion, and reward processing But the roles of the DA neurons in more subtle and spontaneous behaviours remain poorly understood, scientists say. In the latest study, researchers discovered that behaviours like rearing and hunching are associated with the loss of one type of SNc DA neurons, but not those in VTA. These subtle behaviours could serve as key markers of SNc DA neuron loss, and enhance our understanding of Parkinson's, the study found. Scientists used an advanced artificial intelligence behaviour analysis system to examine the movement of two mouse models with a dopamine neuron depletion. Using this approach, researchers could capture detailed and nuanced behavioural features that traditional methods may overlook. The study found reductions in rearing and hunching behaviour in the PD model, which correlates directly with the loss of DA neurons in the SNc but not the VTA. Another behaviour in the mouse models called climbing, which is similar to rearing, was also found to be strongly linked to the loss of DA neurons in the midbrain's SNc area. The findings underscore the need for monitoring rearing behaviour as potential behavioural markers in tracking the progression of Parkinson's disease, scientists say. "Connecting behavioural changes with targeted neural damage advances the understanding of PD progression and offers valuable insights into improving treatment strategies," said Xuemei Liu, an author of the study from the Chinese Academy of Sciences.
