Tag Archives: Mice

Gene Removal Reverses Alzheimer’s Disease in Mice: Breakthrough Findings from Sciworthy

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Alzheimer’s disease presents significant challenges, transforming a cherished family member into someone who often fails to recognize their true self. Many individuals ponder the reasons behind the erosion of memories and personalities. Researchers have identified the primary driver of Alzheimer’s as the accumulation of a brain protein known as Tau.

Under normal circumstances, tau protein plays a crucial role in preserving the health of nerve cells by stabilizing the microtubules, which function as pathways for nutrient transport. However, in Alzheimer’s patients, tau protein becomes twisted and tangled, obstructing communication between cells. These tau tangles are now recognized by medical professionals as a defining characteristic of Alzheimer’s disease, serving as indicators of cognitive decline.

Recent studies have shown that tau tangles correlate with diminished brain function in individuals affected by Alzheimer’s disease. Additionally, the apolipoprotein E4 (APOE4) gene is closely linked to late-onset Alzheimer’s and may exacerbate tau tangling. This gene encodes a protein involved in transporting fats and cholesterol to nerve cells throughout the brain.

A team from the University of California, San Francisco, and the Gladstone Institute has discovered that eliminating APOE4 from nerve cells can mitigate cognitive issues associated with Alzheimer’s. Their research involved specially bred mice exhibiting tau tangles and various forms of the human APOE gene, specifically APOE4 and APOE3. The aim was to determine if APOE4 directly contributes to Alzheimer’s-related brain damage and if its removal could halt cognitive decline.

To investigate the impact of the APOE4 gene, the researchers introduced a virus containing abnormal tau protein into one side of each mouse’s hippocampus. When the mice reached 10 months of age, the team conducted various tests—including MRI scans, staining of brain regions, microscopy, brain activity assessments, and RNA sequencing—to analyze the accumulation of tau protein in the brains of those with and without the APOE4 gene.

The findings revealed significant discrepancies between the two groups. Mice with the APOE4 gene displayed a higher prevalence of tau tangles, a marked decline in brain function, and increased neuronal death, while those with the APOE3 gene exhibited minimal tau deposits and no cognitive decline.

Next, the researchers employed a protein linked to an enzyme called CRE to excise the APOE4 gene from mouse nerve cells, subsequently measuring tau levels with a specialized dye. The results indicated a significant reduction in tau tangles, dropping from nearly 50% to around 10%. In contrast, mice carrying the APOE3 gene saw an even smaller reduction from just under 10% to approximately 3%.

Additionally, a different dye was utilized to quantify amyloid plaques—another protein cluster frequently found in Alzheimer’s cases. The outcomes showed that, following removal of the APOE4 gene, amyloid plaque levels decreased from roughly 20% to less than 10%. Mice with the APOE3 gene, however, displayed no notable change, consistently maintaining around 10% amyloid plaques.

The researchers further analyzed the RNA of the mice to understand how APOE4 affects neurons and other brain cells. Their observations confirmed that the presence of APOE4 correlated with an uptick in Alzheimer’s-related brain cells. This finding helped illustrate that eliminating APOE4 from nerve cells resulted in diminished responses associated with Alzheimer’s disease.

In conclusion, the researchers determined that APOE4 is detrimental and may actively induce Alzheimer’s-like damage in the brains of mice. While further validation in human subjects is needed, the implications of this gene may pave the way for developing targeted therapies for Alzheimer’s disease.

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Source: sciworthy.com

Low-Dose Lithium Alleviates Alzheimer’s Symptoms in Mice

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Illustration of neurons impacted by Alzheimer's Disease

Illustration of neurons affected by Alzheimer’s disease

Science Photo Library / Alamy Stock Photo

Research indicates that administering lithium to mice with low brain levels reverses cognitive decline associated with Alzheimer’s disease. These findings imply that lithium deficiency could contribute to Alzheimer’s, and low-dose lithium treatments may have therapeutic potential.

Several studies have highlighted a relationship between lithium and Alzheimer’s. A 2022 study found that individuals prescribed lithium faced nearly half the risk of developing Alzheimer’s. Another paper published recently linked lithium levels in drinking water with a reduced risk of dementia.

However, as Bruce Yankner from Harvard University points out, hidden variables may influence these results. He suggests that other elements in drinking water, like magnesium, might also contribute to a lower dementia risk.

Yankner and his team assessed metal levels in the brains of 285 deceased individuals, 94 of whom had Alzheimer’s, and 58 exhibited mild cognitive impairment. The remaining participants showed no cognitive decline prior to death.

They discovered that lithium concentrations in the prefrontal cortex (a vital area for memory and decision-making) were about 36% lower in those without cognitive decline, and 23% lower in individuals with mild cognitive impairment. “I believe environmental factors, including diet and genetics, play a significant role,” states Yankner.

There’s another concerning aspect. In Alzheimer’s patients, amyloid plaques exhibited nearly three times more lithium than areas without plaques. “Lithium is sequestered by these plaques,” explains Yankner. “Initially, there’s a lithium intake disorder, and as the disease advances, lithium levels decline further due to its binding to amyloid.”

To further investigate cognitive effects, the research team genetically modified 22 mice to mimic Alzheimer’s symptoms and reduced their lithium consumption by 92%. After around eight months, these mice performed significantly worse on various memory assessments compared to 16 mice on normal diets. For instance, even after six days of training, lithium-deficient mice took approximately 10 seconds longer to locate a hidden platform in a water maze. Their brains also had about 2.5 times more amyloid plaques.

Genetic evaluations of brain cells from the lithium-deficient mice indicated heightened activity of genes linked to neurodegeneration and Alzheimer’s. These mice experienced increased encephalopathy, and their immune cells failed to eliminate amyloid plaques, mirroring changes seen in Alzheimer’s patients.

The researchers then evaluated various lithium compounds for their ability to bind with amyloid and found that orotium— a compound created through the combination of lithium and orotic acid— had the least propensity to be trapped in plaques. A nine-month treatment regimen with orotium significantly diminished amyloid plaques in Alzheimer’s-like mice and improved memory performance compared to regular mice.

These findings point toward the potential of lithium orotium as a treatment for Alzheimer’s. High doses of various lithium salts are already being employed to manage conditions such as bipolar disorder. “A significant challenge with lithium treatment in the elderly is the risk of kidney and thyroid toxicity due to high dosages,” notes Yankner. However, he mentions that the quantities used in this study were about 1,000 times lower than those typically administered, which may account for the absence of kidney or thyroid issues observed in the mice.

Nonetheless, clinical trials are crucial to gauge how low doses of orotium lithium might impact humans, says Rudolf Tansy at Massachusetts General Hospital. “The challenge lies in determining who truly requires lithium,” he adds. “Excessive lithium intake can result in severe side effects.”

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Source: www.newscientist.com

Retinal Implants Regain Vision in Blind Mice

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Retinal damage can result in blindness

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Retinal implants have shown potential in restoring vision in blind mice, indicating that they may eventually help those with conditions like age-related macular degeneration, where photoreceptor cells in the retina deteriorate over time.

Shuiyuan Wang from Fudan University in China and his team developed a retinal prosthesis composed of metal nanoparticles that replicate the function of lost retinal cells, converting light into electrical signals to be sent to the brain.

In their experiments, the researchers administered nanoparticles into the retinas of mice that had been genetically modified to be nearly completely blind.

They restricted water access for three days to both the modified blind mice and those with normal vision. Subsequently, they trained all mice to activate a 6cm wide button on a screen to receive water.

Following training, each mouse underwent 40 testing rounds. The fully sighted mouse pressed the button successfully 78% of the time. Mice with implants achieved a 68% success rate, while untreated blind mice only managed 27%. “That presents a very noticeable effect,” stated Patrick DeGenard, who wasn’t involved in the research but is affiliated with Newcastle University in the UK.

After 60 days, researchers observed minimal signs of toxicity from the implants in the mice. However, Degenaar emphasized the need for long-term safety data, stating, “For clinical application, extensive animal testing lasting approximately five years will be necessary.”

“Patients with age-related macular degeneration and retinitis pigmentosa could benefit from this prosthetic,” noted Leslie Askew from the University of Surrey, UK, who was not part of the study.

Degenaar also remarked that justifying this solution for age-related macular degeneration patients is complex, as they possess a degree of vision that may not warrant the risks associated with implanting prosthetics.

Furthermore, he noted that mice generally have inferior vision compared to humans, raising uncertainty about how beneficial the findings will be for people until comprehensive clinical trials are conducted.

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Source: www.newscientist.com

Scientists resurrect woolly mammoths with genetic technology and call them “mice”

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The first researchers in science created mice that exhibit properties similar to extinct woolly mammoths.

Colossal Biosciences, an American Biotechnology Company, utilized CRISPR genome editing technology to develop the “Colossal Woolly Mouse.”

These mice are not miniature mammoths but have DNA designed to express mammoth-like properties, making them well-suited for cold environments.

An unpublished study published on Biorxiv explains how researchers modified seven mouse genes to give them a woolly coat.

This marks the first instance of a “living model” of animals with mammoth-like attributes.

Two “woolly mice” created by scientists

“Observing these mice is akin to peering into the past through a specialized lens,” said Dr. Louise Johnson, an evolutionary biologist at the University of Reading not involved in the study. “This technology provides an exciting avenue to test our theories about extinct organisms.”

She added, “Researchers successfully adjusted the mouse genome towards the mammoth genome for the first time.”

Through extensive computer analysis, researchers studied mammoth and African elephant genomes from 1.2 million years ago, modifying mouse genes related to hair growth and cold tolerance to create the final edited seven-gene combination. However, these mice do not possess an exact replica of mammoth genes, leading researchers to doubt the genes responsible for mammoth properties.

The Significance of this Discovery

According to Colossal Biosciences, this development is a groundbreaking step in addressing extinction. The company aims to reintroduce other extinct species with the goal of rebuilding ecosystems to maintain Earth’s balance. Founder Ben Lam envisions reviving species like dodos, giant ice age bears, and extinct Tasmanian marsupials known as thylacines.

Not all scientists are convinced of the immediate impact of this discovery.

While genetic manipulation has been used to create various models, including humans and extinct species, some remain skeptical. Professor Dusko Ilic, a stem cell science professor at King’s College London, acknowledges the milestone but warns of potential risks and ethical implications of such experiments.

While comparing mammoth and elephant genomes offers insights into adaptation and genetic traits, transforming mice into mammoth-like creatures may not directly translate to creating woolly elephants adapted for Arctic environments.

Many scientists doubt the feasibility of replicating mammoths through genetic manipulation alone without a complete understanding of their genetic makeup.

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Source: www.sciencefocus.com

Can Genetically Engineered “Woolly” Mice Aid in Reviving the Mammoth?

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Mouse modified to give a “mammoth-like” coat

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There is Estimated genetic differences of 1.5 million Between wool mammoth and an Asian elephant. Colossal Biosciences, a company that seeks to revive extinct species through genetic engineering, now makes mice with “mammoth-like” fur, each with up to five genetic changes. It seems there's still a way to go.

https://www.youtube.com/watch?v=xq9mvp_gg9y

Certainly, these mice have long, curly hair and blonde hair. In that way, it resembles a wool mammoth coat stored in permafrost. However, it is not clear that bringing the same genetic alterations in Asian elephants with far fewer hairs per area of ​​the skin will result in similar results.

“The work done with these mice doesn't mean there's a solution ready to regain the huge phenotype,” says team members. I love Darren At Stockholm University in Sweden, on the Scientific Advisory Committee of Corosal. “As you point out, we also need to understand how to grow more fur.”

Creating an Asian elephant with these genetic changes would also be much more difficult than doing it in a mouse. “Engineering mutations in mice are an established process and are not particularly challenging.” Dusko Ilic King's College London.

Mouse that has been fixed and unfixed

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Techniques that work in mice often fail in other species, and the size of elephants and their slow breeding significantly increases the time and cost involved. “These methods have not been developed for elephants. They are not easy based on anatomy.” Vincent Lynch At Buffalo University, New York. “That's probably the biggest challenge.”

However, Lynch is undoubtedly achievable. surely, Thomas Hildebrandt At the Leibniz Institute for Zoo and Wildlife Research in Berlin, Germany – Another giant advisor – New Scientist His team is the first time they've collected eggs from elephants, but the results have not yet been made public. Egg collection is an important step in IVF and is a genetic modification of mammals.

https://www.youtube.com/watch?v=QGT8SOKDSXO

So how did Colossal make a “mammoth” mouse? Researchers began by looking for known mutations in mice that looked like fur. “[T]The majority of these genes were selected based on previous observations of the coat phenotype in mice,” read in a paper published today, which has not been peer-reviewed.

They identified eight genes that affect patterns (curse), color and hair length when disabled in mice. According to Colossal, one of these eight is a mammoth and is naturally disabled.

From the mammoth genome, the team identified small mutations that are thought to affect hair patterns, along with another disordered gene involved in fat metabolism.

The company then tried to modify these genes in mice. For example, one experiment used CRISPR gene editing to attempt to disable five of these genes in fertilized eggs. From 134 edited eggs, 11 puppies were born, and one of these puppies invalidated copies of both five genes.

Fur stored in frozen mammoth rank

Arami Stock Photo

In another study, the researchers used a form of CRISPR called base editing to abolish several genes in embryonic mouse stem cells. They combined this with another technique called homologous recombination to create the exact mutations found in the mammoth genome. Make accurate changes is much more difficult than disabling genes, but the recombination method works well only in the mouse.

The team then sequenced the cells to identify cells with the desired change and injected into mouse embryos to create chimeric mice. Of the 90 injected embryos, seven mice were born with four intended changes.

These experiments can be said to be successful in producing several mice with desirable physical changes in the fur, but only one genetic change is in exact agreement with what is found in the mammoth genome. It takes more work to achieve Colossal's stated purpose With the creation of “a cold-resistant elephant with all the core biological properties of wool mammoths,” and the elephant pregnancy lasting for about two years, Colossal is in time for a spontaneous 2028 deadline.

“Elephants with fur are not mammoths in the way we think of them.” Juan Antonio Rodriguez At the University of Copenhagen, Denmark. He says many of the 1.5 million differences between the mammoth and the Asian elephant genome may not be effective, but it is not clear which is more important.

Even if we did, it's dangerous to make broader changes, says Rodriguez. “The more things change in organisms, the more likely they are to tinker with major metabolic pathways and genes.”

Rodriguez, Lynch and Irik are all

Source: www.newscientist.com

Scientists use genes from pre-animal choanoflagellates to recreate mice

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Scientists at Queen Mary University of London and the University of Hong Kong have utilized genetic tools from single-celled organisms that share a common ancestor with animals to create mouse stem cells capable of producing fully developed mice.

Choanoflagellate Sox can induce pluripotency in mammalian cells. Image credit: Gao others., doi: 10.1038/s41467-024-54152-x.

Alex de Mendoza, a researcher at Queen Mary University of London, and his colleagues used genes found in choanoflagellates, single-celled organisms related to animals, to create stem cells that were then employed in giving birth to living, breathing mice.

Choanoflagellates are the closest living relatives of animals, housing genes in their genomes that support pluripotency in mammalian stem cells, including versions of Sox and POU.

This surprising discovery challenges the notion that these genes only evolved within animals.

“With the successful creation of mice using molecular tools derived from our single-celled relatives, we are witnessing an incredible continuity of function spanning nearly a billion years of evolution,” Dr. Mendoza stated.

“This research suggests that crucial genes involved in stem cell formation may have originated well before the stem cells themselves, potentially paving the way for the multicellular life we observe today,” he added.

Shinya Yamanaka, who won the Nobel Prize in 2012 for demonstrating the obtainment of stem cells from differentiated cells by expressing factors such as Sox (Sox2) and POU (Oct4) genes, highlighted the significance of the study.

In their research, Dr. de Mendoza and co-authors incorporated the choanoflagellate Sox gene into mouse cells, leading to reprogramming into a pluripotent stem cell state.

These reprogrammed cells were then injected into developing mouse embryos to assess their efficacy.

The resulting chimeric mice displayed physical attributes from both donor embryos and laboratory-derived stem cells, highlighting the essential role these ancient genes play in shaping animal development.

This study showcases how early versions of the Sox and POU proteins, known for binding to DNA and regulating other genes, were utilized by unicellular ancestors for functions critical to stem cell development and animal growth.

“Despite choanoflagellates lacking stem cells and being unicellular organisms, they possess these genes, likely governing fundamental cellular processes that multicellular animals later repurposed to construct intricate bodies,” Dr. Mendoza explained.

“This newfound insight underscores the evolutionary adaptability of genetic tools and how early life forms employed similar mechanisms for controlling cell production, even before the emergence of truly multicellular organisms,” he concluded.

“This discovery goes beyond evolutionary biology and could lead to innovative advancements in regenerative medicine.”

A paper detailing the study findings was published in Nature Communications.

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Y. Gao others. 2024. The appearance of Sox and POU transcription factors predates the origin of animal stem cells. Nature Communications 15, 9868;doi: 10.1038/s41467-024-54152-x

This article is based on a press release provided by Queen Mary University of London.

Source: www.sci.news

Silk hydrogel battery could power pacemakers in mice

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A small soft lithium-ion battery made from water droplets

oxford university

The smallest soft lithium-ion battery ever made consists of just three tiny droplets formed from a silk-based hydrogel. Droplet batteries can provide pacemaker-style control and deliver defibrillator shocks to beating mouse hearts, but could eventually be used in biomedical implants and wearable electronics for humans. It may supply electricity.

“Potentially, our small battery could be used as an implantable microrobotic battery, which could be moved to a target location by a magnetic field and release its energy for treatment.” . Yuka Zhang at Oxford University.

Zhang and colleagues designed the small battery as three connected droplets that can self-assemble in solution after injecting various components into the liquid with a microsyringe. One droplet contains lithium manganese oxide particles and serves as the battery's negative electrode. The second droplet contains lithium titanate particles and serves as the positive electrode. A central droplet filled with lithium chloride separates these electrodes. UV light energizes the battery by breaking down the layers that separate each droplet, allowing lithium ions to flow freely between the droplets.

Droplet batteries are one-tenth the length of traditional soft lithium-ion batteries. At just 600 micrometers, it is about six times as wide as a human hair. The battery is also 1000 times smaller in volume than similar flexible lithium-ion batteries. The central droplet can also incorporate magnetic nickel particles, allowing the battery to be controlled remotely via an external magnetic field.

Such a small battery also provides an unprecedented amount of energy considering its small size. Wei Gao at the California Institute of Technology. “This energy density is significantly higher than what has been achieved with other similarly sized batteries,” he says.

The droplet battery was tested on a mouse heart removed from the animal's body. These successfully functioned as defibrillators to restore normal heartbeats and as pacemakers to regulate heartbeats. Additional testing showed that the battery retained 77% of its original capacity after 10 charge/discharge cycles.

The simplicity and scalability of such droplet batteries could be a potential advantage over traditional battery manufacturing in the future, Gao said. He suggested that such batteries could power minimally invasive biomedical implants and biodegradable medical devices.

“What impressed me most is how this soft battery mirrors the aqueous environment of human tissue by being hydrogel-based,” Gao says. “However, we still need to consider the safety and biocompatibility of the materials used in this battery, especially as we move towards commercialization and further research applications.”

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Source: www.newscientist.com

Hannah Fry discusses the science of laughter: Monkeys enjoy being tickled, mice giggle | Revealing the formula for life by Hannah Fry

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The British sense of humor is cherished among Brits, but it’s natural to assume that many British jokes may be embarrassing to other cultures. There is an interesting point to consider here – humor is not universal. What one finds amusing is not inherent, but rather cultural.

Humor differs significantly from laughter, which is a common experience for all human beings, even the grumpiest ones. Laughter is much easier to comprehend and study scientifically.

For instance, TV producers have long understood that incorporating a pre-recorded “laugh track” can make people perceive something as funnier compared to when they don’t hear that laughter (I’m Looking at You, 90’s Sitcom). However, neuroscientist Robert Provine found that jokes are not even necessary. In a study conducted in 2013, Provine solely played the laugh track, which surprisingly was adequate to induce laughter in nearly all participants.

Provine’s groundbreaking research on laughter involved observing it in real-world settings rather than just in a lab. Observing people laughing in public, he empirically proved that individuals are significantly more likely to laugh in the presence of others than when alone, approximately 30 times more likely. Moreover, laughter is not necessarily a response to finding something funny but serves as a form of social communication, indicating a positive, nonthreatening interaction.

Laughter is not exclusive to humans; it is observed across the animal kingdom. For example, apes enjoy being tickled and vocalize their enjoyment while playing. Kea parrots are known for their playful behaviors and have distinct calls to amuse others. Additionally, mice produce ultrasonic giggles when playing. Rats tickled regularly by their owners exhibit immediate laughter upon the owner’s arrival, displaying excitement for playtime.

Powered by Galaxy AI to provide resourceful assistance
Thanks to the Chat Assist feature on the new Samsung Galaxy Z Flip6, Galaxy AI analyzes your chats and messages in real-time and displays contextual suggestions as you type to help craft the perfect reply. Therefore, choosing a casual tone is likely to include lighter and wittier touches.

However, humor poses a greater challenge in understanding. What makes certain things more amusing than others? And how do you define what is considered amusing, depending on individual perspectives?

One compelling explanation for humor is that it involves the buildup and release of tension. This concept can explain some well-known comedic moments, such as Del Boy falling on the bar, Basil Fawlty hitting a car with a tree branch, or Mark Simmons’ joke at the Edinburgh Fringe: “I planned to sail around the world in the smallest ship, but chickened out.” These instances are humorous, especially when viewed from a non-human perspective.

Generative AI, trained on vast internet data, is adept at replicating various humor styles, including generating jokes based on given parameters. When prompted with a framework like, “I thought I was going to sail around the world in the world’s smallest ship…”, an AI chatbot replied, “I felt like I was sinking.” Not a bad attempt, right?

However, creating the framework itself, i.e., original humor, involves distilling quirky and unconventional ideas that resonate with shared human experiences but lack any firsthand experience of the world beyond online sources. For now, these unique concepts offer intriguing ways to engage with audiences.

Source: www.theguardian.com

The discovery of new adrenal cells enhances parenting abilities in mice

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During evolution, new types of cells emerge and perform new functions, resulting in changes in animals. Scientists study the origin and development of these new cell types to understand how they affect the animal’s bodily functions, structure, or behavior.

Scientists previously Mammalian ancestors Mammals live solitary lives, and parental care of young has developed over time in some mammalian groups. A research team led by scientists from Columbia University in New York recently used two closely related mouse species to elucidate how parental care evolved in mammals. The first species, the Asian goshawk, is monogamous and displays strong parenting behaviors, including grooming, herding, and retrieving young that have strayed from their nests. The second species, the deer mouse, is promiscuous and does not display parenting behaviors. The researchers aimed to investigate the genetic drivers of parental care in Asian goshawks.

They performed their experiments on two small clusters of cells located in the top part of each kidney. Adrenal glands These glands produce fat hormones, Steroid hormones Once produced, it immediately affects bodily function. The researchers found that the adrenal glands of monogamous Oldfield mice were six times heavier than those of promiscuous deer mice, an unexpectedly large size difference for such closely related species. When the researchers examined the tissue composition of both glands, they realized that the larger adrenal glands of Oldfield mice were due to larger and more numerous adrenal cells.

To look for molecular differences between the adrenal glands of the two mouse strains, the team studied the RNA molecules in their glands. RNA molecules copy genetic instructions from DNA and carry out the functions of genes. By counting and comparing the types and amounts of RNA molecules in the adrenal glands, the scientists hoped to understand how the adrenal glands functioned differently. They took adrenal tissue from adult mice, broke it down to release the RNA, and counted that RNA. They looked for differences in the amount of RNA, called ribosomal RNA. Akrc18 This level was 3,200 times higher in Oldfield mice than in deer mice, a difference that led the researchers to wonder whether this RNA might be related to the parental behavior seen in Oldfield mice.

The researchers, Akrc18 It produces steroid hormones. Steroid hormones affect parental behavior, so the team tested whether the hormone had an effect on mice. They gave Oldfield mice a single dose of the hormone and measured their parental behavior 20 hours later. They observed that these mice groomed and cuddled their pups longer, brought them back to their nests more frequently, and built stronger nests. In deer mice, which don’t normally show parental behavior, 17% of the injected mice groomed and brought back their pups. From these results, the scientists concluded that the hormone shapes the parental behavior of Oldfield mice.

The researchers also explained that mate bonding is an important aspect of monogamy. To understand partner choice, the researchers measured how long mice huddled with their partners compared to opposite-sex mice of the same species. They found that monogamous Oldfield mice huddled three times longer with their partners than with new individuals, whereas promiscuous deer mice huddled neither with their partners nor with strangers. Injecting the Akrc18 steroid hormone did not change these preferences, suggesting that the hormone only affected parenting behavior and not pair bonding.

The research team found that Oldfield mice had larger adrenal glands and that Akrc18 RNA production was related. To test whether the adrenal glands of the two mouse species had different cell types, the researchers used the RNA from the adrenal glands of both mice that they had previously counted. They used computational methods to search for specific RNAs in the cells and identify what cell types were present. They found that nearly all cell types were shared between the two species, except for one type that was present in Oldfield mice but not in deer mice.

Also, Akrc18 RNA was the most abundant element in these new cells. The researchers examined the structure and composition of the tissue and observed these cells lining the adrenal glands of wolf mice, which are absent in deer mice. The researchers suggested that these cell types may have evolved from existing adrenal cells by increasing production of steroid hormones and related genes. The researchers concluded that the parenting behavior of wolf mice is linked to this new type of cell in the adrenal glands.


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Source: sciworthy.com

Injecting Neurons into Rats Gives Mice the Ability to Smell Cookies, Despite Their Lack of Olfactory Function.

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Mouse brain hippocampus (red) containing some rat cells

M. Kadish Imtiaz/Columbia University Irving Medical Center (CC BY-NC-ND)

Rat cells grown in the brains of mice without a sense of smell have enabled them to acquire the sense of smell. This is the first time that one species has experienced the world through the sensory neurons of another species.

When cells of one species multiply within the body of another species, the resulting organism is known as an interspecies chimera. These have previously been used to study specific tissues, such as mice containing cells of the human immune system, to study disease responses. However, creating chimeras of other tissues, such as neural tissue, is more complex.

Researchers at the University of Texas Southwestern Medical Center previously bred mice with parts of rat brains transplanted into them. Now, another team of researchers has shown that this cross-species chimerism may confer the ability to smell in mice genetically modified to lack scent-sensing neurons.

christine baldwin The researchers at Columbia University in New York injected these engineered mouse embryos with rat stem cells. Once the embryos became adult mice, the researchers monitored neuronal activity. The researchers discovered that these animals have functional neural pathways for sensing odors, made up of both rat and mouse cells that can communicate directly with each other.

When researchers tested these mice's sense of smell by searching for hidden mini Oreo cookies, they found that the mice that received stem cell injections found the food more easily, as opposed to the same genetically modified mice. It turned out that it was possible. It wasn't a chimera.

“This is a huge opportunity for human health, allowing us to better understand how to create cell replacement therapies for humans,” Baldwin said. “We can also create models in mice and rats for diseases that affect long-lived organisms.”

The fact that rat cells were able to facilitate food exploration in mice, which normally don't have a sense of smell, is very impressive, he says. walter lowe at the University of Minnesota. “Now, it is not yet clear whether something similar to this can occur in even different species, but at least [this study] Shows what's happening in two relatively close species [in evolutionary terms]” he says.

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Source: www.newscientist.com

Antibody treatment restores immune function in elderly mice

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Antibodies are proteins that can target and attack specific cells.

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An experimental treatment rejuvenates the immune systems of older mice and improves the animals’ ability to fight infections. If this treatment is effective in humans, it could reverse the age-related decline in immunity that makes older people more susceptible to illness.

These reductions may be due to changes in blood stem cells, which can develop into all types of blood cells, including important components of the immune system. As we age, a greater proportion of these stem cells tend to produce some immune cells than others. Jason Ross at Stanford University in California. This imbalance impairs the immune system’s ability to fight infection. It also promotes chronic inflammation, which accelerates aging and increases the risk of age-related diseases such as heart disease, cancer, and type 2 diabetes.

Ross and his colleagues have developed a treatment that uses antibodies, proteins that recognize and attack specific cells, to target these biased stem cells. Next, they tested the treatment on six mice aged 18 to 24 months. This is roughly equivalent to a human being between 56 and 70 years old.

One week after receiving the antibody injection, these abnormal stem cells in the mice had decreased by about 38 percent compared to six rodents of the same age who did not receive treatment. They also had significantly higher amounts of two types of white blood cells important for recognizing and fighting pathogens, and lower levels of inflammation.

“You can think of this as turning back the clock,” says Ross. “We are adjusting these percentages [immune] more similar cells [those of] A young adult mouse. ”

To test whether these changes result in a stronger immune system, the researchers vaccinated 17 older mice with a mouse virus. Nine of these mice had received antibody treatment eight weeks earlier. The researchers then infected rodents with the virus. After two weeks, the number of infected cells in the animals was measured and it was found that almost half of the treated mice (4 out of 9) had completely cleared the infection, compared to 1 out of 8 of the untreated mice. It turned out that there was only one.

Taken together, these findings demonstrate that antibody treatment rejuvenates the immune system of aged mice. Humans, like rodents, have more abnormal blood stem cells as they age, so a similar antibody treatment could also boost their immune systems, Ross said.

Such a possibility is still far away, robert signer at the University of California, San Diego. First, we need a better understanding of the potential side effects of treatments. In an accompanying article, Signer and his colleagues write: Yasar al-Fat KassResearchers, also at the University of California, San Diego, suggest that depletion of stem cells, even abnormal stem cells, may increase cancer risk. On the other hand, “if you have a better immune system, you’ll be better at investigating cancer, so we don’t know exactly what will happen yet,” Signer says.

Still, Ross says these findings are a promising advance in understanding age-related immune decline and how to reduce it.

Aging is the biggest risk factor for various diseases. “Rejuvenating or improving immune function in older adults could really help fight infectious diseases,” Signer says. “It may also have an impact on different types of chronic inflammatory diseases. That’s what’s so exciting here.”

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Source: www.newscientist.com

Brain researchers discover cold sensors in mice

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Neuroscientists at the University of Michigan have identified thermoreceptors that mediate the sensation of cold in somatosensory neurons.

GluK2 KO mice have a defect in cold sensing.Image credit: Kai other10.1038/s41593-024-01585-8.

“The field began elucidating such temperature sensors more than 20 years ago with the discovery of a heat-sensing protein called TRPV1,” said Professor Sean Hsu of the University of Michigan.

“While various studies have discovered proteins that sense hot, warm, and even cold temperatures, we have not identified any proteins that sense temperatures below about 15 degrees Celsius (60 degrees Fahrenheit).”

In 2019, scientists discovered The world's first cold receptor protein Caenorhabditis elegans a millimeter-long nematode species that the lab is studying as a model system for understanding sensory responses.

Because the gene that codes for it is Caenorhabditis elegans This protein is evolutionarily conserved across many species, including mice and humans, and this discovery was a starting point for testing cold sensors in mammals. Glutamate ion channel receptor kainate type subunit 2 (GluK2).

In a new study, Professor Xu and colleagues tested that hypothesis in mice with the deficiency. GluK2 Because of the gene, the GluK2 protein could not be produced.

Through a series of experiments testing animals' behavioral responses to temperature and other mechanical stimuli, they found that mice responded normally to hot, warm, and cold temperatures, but not to harmful cold.

GluK2 is primarily found in neurons in the brain, where it receives chemical signals and facilitates communication between neurons.

However, it is also expressed by sensory neurons in the peripheral nervous system (outside the brain and spinal cord).

“We found that this protein serves a completely different function in the peripheral nervous system, processing temperature cues instead of cold-sensing chemical signals,” said Dr. Bo Duan from the University of Michigan.

of GluK2 This gene has relatives across the evolutionary tree, going back to single-celled bacteria.

“Bacteria don't have brains, so why have they evolved a way to receive chemical signals from other neurons?” Professor Xu said.

“But the need to sense its environment, and perhaps both temperature and chemicals, will be very strong.”

“Thus, I suspect that temperature sensing is an ancient function, at least for some of these glutamate receptors, that was eventually adopted as organisms evolved more complex nervous systems. .”

of result appear in the diary natural neuroscience.

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W. Kai other. The kainate receptor GluK2 mediates cold sensing in mice. nut neurosi, published online on March 11, 2024. doi: 10.1038/s41593-024-01585-8

Source: www.sci.news

Could two genetically engineered mice save Valentine’s Day?

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love time

Valentine's Day celebrates coupling. Alan McWilliam told Feedback about an offer he received from a US-based biotech company before the most recent Valentine's Day. It combines charm with other qualities.

Alan says: “I received the following marketing email. I have never before been offered a “free breeding pair of genetically modified mice” for Valentine's Day. What could be more romantic than staring into the eyes of a mouse over the flame of a Bunsen burner before implanting a tumor and humanely euthanizing it a few weeks later? ”

Here are the notes:

“Dear Alan,

love is in the air, [REDACTED]share the love with a special Valentine's Day promotion just for you.

Theme: The perfect combination in research

Promotion: This Valentine's Day, we're giving away a free breeding pair of genetically modified mice using our genetic targeting service.

Coupon code: FREECOUPLE

This limited time offer is designed to enhance your studies and provide you with the perfect study companion. ”

Regardless of the romantic or commercial effects of this offer, its most powerful use may be as a psychological test. How would a person seemingly react to this opportunity?

political restraint

With a growing trove of top-notch data, British psychology researchers are keen to sift through it for lessons about leadership. Feedback infers this from news accounts.

of BMJ (formerly known as this) british medical journal) create medical care Note It has been reported that Chancellor Rishi Sunak is “fasting for 36 hours at the beginning of every week''. Sunak's past and current medical data may be of interest and inspiration to physicians, psychologists, and nutritional researchers. Over time, does the body of evidence expand or contract? How much of that inflation or deflation is due to leaders' first-person food control?

More complete data may already be available about the effects and effectiveness of self-regulation (or basically self-asserted restraint) by former Prime Minister David Cameron, who served as Prime Minister from 2010 to 2016. There is sex.

new scientistA 2015 report on Cameron Fluid Engineering explains: While this technique may be effective, it also appears to help people tell more convincing lies. ”

(By a happy coincidence, the 2011 Ig Nobel Prize in Medicine was awarded to Award It was given to researchers in the UK, Netherlands, Belgium, Australia and the US to test the effectiveness of the delayed voiding technique. The award was announced naked weeks before Prime Minister David Cameron went public with his penchant for peeing. )

If it someday turns out that other British prime ministers have also exercised restraint, researchers will have even more data available.

Under the tarantula hole

Fascinating and surprising delights about living things can linger in the bibliography section of scientific papers about things that went extinct long ago.

Trilobite researchers still chat about their research. ”Frontal auxiliary impression of the Ordovician trilobite Darmanitina reed, 1905, from Varandian region, Czech Republic.' was published a few years ago. Earth Science Bulletin.

But only the most diligent researchers discovered something unexpected deep in the bibliography section at the end of the paper. It was a reference to the paper “''.Connection between heart and sucking stomach during tarantula ingestionWritten by Jason Dunlop, John Altringham, and Peter Mill, published in 1992 Journal of Experimental Biology.

And deep within that heart- and stomach-sucking paper lurks a different kind of surprise, a reminder that scientists must always proceed with caution. “In the absence of detailed information about the tarantula's body fluid flow, any model is speculative.”

gentle youth

Dave Kirby noticed another cookbook: anarchist cookbookperhaps a warning is needed (feedback suggested something like “If you don't cook the anarchist to the correct temperature, you may run into problems”).

Dave says: “In addition to the books you mentioned, you can also add the following. River Cottage Baby and Toddler Cookbook. My local restaurant's bookshelf is full of cookbooks, and I found this one there a few months ago.

“I was hesitant to look at the fine print on the menu.”

Depending on the cat

This is probably reassuring news for people who fear being temporarily separated from their cats.

A study conducted in California titled “Comparing people's attachment to romantic partners and pet cats'' was published in the journal anthropozoanAccording to a report, some people “don't necessarily need the reassurance from a cat or feel distressed in its absence, as would be the case with a romantic partner.”

Mark Abrahams hosted the Ig Nobel Prize ceremony and co-founded the magazine Annals of Improbable Research. Previously, he was working on unusual uses of computers.his website is impossible.com.

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Source: www.newscientist.com

Researchers Develop VR Goggles for Mice

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Scenarios Mouse might see when wearing virtual reality goggles

Dom Pinke

Tiny virtual reality goggles for mice create a convincing world in which scientists can study animal brain activity in a variety of scenarios. This technology brings rodent neuroscience even closer to simulations that are indistinguishable from the real world, researchers say.

For about 20 years, Daniel Dombeck Researchers at Northwestern University in Illinois used rudimentary virtual reality to learn more about how the mouse brain works.

The machines used to observe brain patterns are too large to attach to freely moving mice. Instead, the researchers kept a mouse inside such a machine and placed a screen around the mouse that displayed a virtual reality world when it was placed on a treadmill. The researchers were able to create a virtual world where the mouse could navigate any environment they designed.

“We can run them through a virtual maze and image their brains to see which neurons form memories and remember where they are,” Dombeck says. “[But] What the animal sees is a flat surface, there is no depth perception, and the mouse sees things that are not part of the projection. So there’s a collision of all these cues around us, and we think they’re not fully engaged and immersed in the environment. They are not completely fooled.”

To solve this problem, researchers have now created tiny goggles with a different screen for each eye to cut out everything but the virtual world from the mouse’s field of view and create convincing depth perception. They believe this allows them to perform more accurate experiments because the mice become more convinced of the illusion and behave more naturally.

But designing goggles for mice isn’t as simple as simply miniaturizing technology made for humans. A human’s field of view is just over 200 degrees, while a mouse’s field of view is up to 320 degrees.

This means that the screen inside the goggles needs to be curved and almost surround the eyeball. Although the screen can only display 400 pixels by 400 pixels, Dombeck says that’s enough to be convincing, since mouse vision is much less detailed than human vision.

“The first use of goggles on the first set of mice was quite remarkable,” says Dombeck. “The rats seemed to engage very quickly. When you put the goggles on, it’s pitch black and you can’t see anything, and the virtual rendering turns on. The first rat sat up and said, ‘Oh, what is this?’ It was that kind of feeling. It then started moving pretty naturally, which doesn’t usually happen with flat projection screens.”

Dombeck says the long-term goal is to make mouse technology comparable to what’s seen in mice, with additional devices to trick the senses of smell, hearing, and touch.

topic:

Source: www.newscientist.com