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Comment by Dr. Krishna Kumari Challa on February 5, 2025 at 12:45pm

What is brown fat?

Comment by Dr. Krishna Kumari Challa on February 5, 2025 at 12:39pm

They used CRISPR to activate genes that are dormant in white fat cells but are active in brown fat cells, in the hopes of finding the ones that would transform the white fat cells into the hungriest of beige fat cells.

A gene called UCP1 rose to the top.

Then, the researchers grew UCP1 beige fat cells and cancer cells in a "trans-well" petri dish. The cancer cells were on the bottom and the fat cells were above them in separate compartments that kept the cells apart but forced them to share nutrients.

The results were shocking.
In their very first trans-well experiment, very few cancer cells survived.
The beige fat cells held sway over two different types of breast cancer cells, as well as colon, pancreatic and prostate cancer cells.

But the researchers still didn't know if the implanted beige fat cells would work in a more realistic context.
So, the scientists turned to fat organoids, which are coherent clumps of cells grown in a dish, to see if they could beat tumor cells when they were implanted next to tumors in mice.

The approach worked against breast cancer, as well as pancreatic and prostate cancer cells. The cancer cells starved as the fat cells gobbled up all the available nutrients.

The implanted beige fat cells were so powerful that they suppressed pancreatic and breast tumors in mice that were genetically predisposed to develop cancer. It even worked when the beige fat cells were implanted far away from the breast cancer cells.
When tested with removed cancer breasts, these same-patient beige fat cells outcompeted breast cancer cells in petri dishes—and when they were implanted together in mouse models.

Knowing that cancers have preferred diets, the researchers engineered fat just to eat certain nutrients. Certain forms of pancreatic cancer, for example, rely on uridine when glucose is scarce.

So, they programmed the fat to eat just uridine, and they easily outcompeted these pancreatic cancer cells. This suggests that fat could be adapted to any cancer's dietary preferences.
Fat cells have many advantages when it comes to living cell therapies.

Hai P. Nguyen et al, Implantation of engineered adipocytes suppresses tumor progression in cancer models, Nature Biotechnology (2025). DOI: 10.1038/s41587-024-02551-2

Part 2

Comment by Dr. Krishna Kumari Challa on February 5, 2025 at 12:34pm

Hungry fat cells could  starve cancer to death

Liposuction and plastic surgery aren't often mentioned in the same breath as cancer. But they are the inspiration for a new approach to treating cancer that uses engineered fat cells to deprive tumors of nutrition.

Researchers  used the gene editing technology CRISPR to turn ordinary white fat cells into "beige" fat cells, which voraciously consume calories to make heat.

Then, they implanted them near tumors the way plastic surgeons inject fat from one part of the body to plump up another. The fat cells scarfed up all the nutrients, starving most of the tumor cells to death. The approach even worked when the fat cells were implanted in mice far from the sites of their tumors. Relying on common procedures could hasten the approach's arrival as a new form of cellular therapy.

Doctors already routinely remove fat cells with liposuction and put them back via plastic surgery. These fat cells can be easily manipulated in the lab and safely placed back into the body, making them an attractive platform for cellular therapy, including for cancer.

Beige fat cells outcompete cancer cells for nutrients. That is why exposure to cold could suppress cancer in mice.

One remarkable experiment even showed it could help a patient with non-Hodgkin lymphoma. Scientists concluded that the cancer cells were starving because the cold was activating brown fat cells, which use nutrients to produce heat.

But cold therapy isn't a viable option for cancer patients with fragile health.

So the researchers turned to the idea of using beige fat, wagering that they could engineer it to burn enough calories, even in the absence of cold, to deprive tumors of the fuel they needed to grow.

Part 1

Comment by Dr. Krishna Kumari Challa on February 5, 2025 at 12:26pm

Image source : tandfonline.com

Part 2

Comment by Dr. Krishna Kumari Challa on February 5, 2025 at 12:22pm

Phage Therapy: Helping viruses deliver a knockout blow to killer bacterial infections

In the face of rising concerns about antibiotic resistant infections, an international group of microbial experts have launched a powerful and flexible free online genomic toolkit for more rapid development of phage therapy.

After decades of research, phages or bacteriophage viruses that target and kill specific bacteria are seen as the next frontier in finding fast and effective ways to curb the death toll and serious illnesses caused by antibiotic resistant "superbugs" every year.

The lead developers of the new platform, called Sphae, claim it is capable of assessing if a phage is suitable for a targeted therapy in under 10 minutes.

This marks a big step forward in quickly evaluating phage safety and suitability for addressing antibiotic-resistant infections, according to the team at Flinders Accelerator for Microbiome Exploration (FAME) and collaborators in a new article just published in the journal Bioinformatics Advances.

Sphae integrates high-throughput sequencing technologies with advanced computational pipelines, enabling researchers to analyze vast and complex datasets efficiently. It  prioritizes safety, flagging genes associated with toxins or undesirable traits to ensure that only the safest candidates are advanced for therapeutic use.

Adaptability and scalability sets Sphae apart. The workflow supports a wide range of sequencing technologies while the toolkit can handle the massive datasets typical of high-performance computing environments, making it an invaluable tool for labs tackling large-scale projects.

Sphae not only aids in therapeutic research but also advances our broader understanding of microbial ecosystems and their impact on global health and climate. Sphae processes multiple phage genomes at once, saving time and efficiently handling larger datasets.

Sphae works effectively even in mixed or challenging datasets, providing consistent and accurate results to help identify phages that can potentially combat resistant bacterial strains.

It offers a complete view of phage genomes, summarizing key features like resistance and virulence markers for better insight into phage safety and functionality.

When conventional antibiotics are not effective any more, personalized phage therapy could become a standard part of medical practice by simplifying and accelerating the discovery of therapeutic phages suited to the individual patient's infection. The future of medicine lies in the precise, efficient, and safe use of phages to combat bacterial infections and restore hope to patients worldwide.

Bhavya Papudeshi et al, Sphae: an automated toolkit for predicting phage therapy candidates from sequencing data, Bioinformatics Advances (2025). DOI: 10.1093/bioadv/vbaf004

Comment by Dr. Krishna Kumari Challa on February 5, 2025 at 12:01pm

Human influence has led to loss of dialects in chimpanzees, long-term study suggests

A new study, conducted on wild chimpanzees (Pan troglodytes verus) in Taï National Park, Côte d'Ivoire, provides evidence that the gestures used by male chimpanzees from four neighboring communities during copulation requests may reflect different dialects. One gesture, used predominantly in one community, disappeared from the repertoire 20 years ago after a poaching incident and did not return. This incident documents a cultural loss associated with human-induced population decline, a phenomenon rarely documented in animals.

Much like people from different regions speak with different accents or use unique expressions, many animals have their own "dialects." Songbirds such as sparrows and finches, or even whales, learn their songs from others, resulting in variations that are as unique to a region as local accents in humans. However, in primates, which are phylogenetically closer to humans, evidence for community-specific dialects remains surprisingly scarce, presenting an intriguing area for further scientific investigation.

Researchers observed members of the four neighboring communities of wild chimpanzees every day from the time they left their nests in the morning until they went to sleep at night. Their work is published  in the journal Current Biology.

Researchers identified four types of communicative gestures, 'heel kick,' 'knuckle knock,' 'leaf clip' and 'branch shake,' used by male chimpanzees to attract females to mate with them. Between 2013 and 2024, they found differences in the frequency of use of these communicative gestures between neighboring chimpanzee communities, but also between populations across Africa.

Using long-term data from 45 years of research in the Taï Chimpanzee Project, the researchers also revealed variations in gesture use over time. These findings highlight the ability of humans' closest living relatives to produce cultural differences in communicative signals.

The consistent use of the same mating request signal forms within communities, but different signal forms between neighboring communities that experience regular gene flow through female migration, suggests socially learned dialects in chimpanzees, evidence that has rarely been demonstrated before.

These days, males in the North group, one of the four communities, have not been observed to use the 'knuckle knock' for 20 years, although all males in the North group used this gesture before 2004.

Following a series of human-induced events leading to demographic loss, the last adult male of the North group was killed by a poacher, resulting in several years without an adult male.

The loss of competition between adult males for females or the loss of all role models could be responsible for the cultural loss of this specific copulation request gesture in this community.

This finding provides evidence that human illegal activities have altered the cultural behavior of chimpanzees.

There is an urgent need to integrate the preservation of chimpanzee culture into conservation strategies, the researchers say.

Mathieu Malherbe et al, Signal traditions and cultural loss in chimpanzees, Current Biology (2025). DOI: 10.1016/j.cub.2024.12.008

Comment by Dr. Krishna Kumari Challa on February 5, 2025 at 11:50am

How eye saccades enable mammals to simultaneously chase prey and navigate through complex environments

How do predators use their vision to both navigate through the terrain while tracking prey running for its life? Pursuing prey through a complex environment is a major challenge for the visual system, as not only does the prey constantly change direction, sometimes in the opposite direction to the pursuer, but running after something evokes self-induced motion-blur that degrades vision.

To investigate this question, researchers reconstructed the visual fields of freely moving ferrets that were chasing a fleeing target and discovered that eye saccades (very rapid coordinated eye movements) align the world motion—and not the actual thing they are chasing—to the retina and retinal specializations used for high-acuity vision.

Saccades achieve this by countering head rotations to align the area of the sharpest vision with the direction of intended travel and the area of the least motion-induced blur. This enables image blur, which degrades vision, to be minimized over these specialized retinal areas during turns when chasing targets that are trying to evade capture.

These eye movements are seen in freely moving ferrets, mice, rats and tree shrews, suggesting a generalized mechanism enabling mammals to navigate complex environments during pursuit.

The research is published in the journal Current Biology.

 Eye saccades align optic flow with retinal specializations during object pursuit in freely moving ferrets, Current Biology (2025). DOI: 10.1016/j.cub.2024.12.032. www.cell.com/current-biology/f … 0960-9822(24)01700-7

Comment by Dr. Krishna Kumari Challa on February 5, 2025 at 11:18am

This finding fundamentally differs from what is observed in some birds, another well-studied migratory group. For example, in willow warblers, a large chromosomal region has been associated with variable migratory direction, illustrating how different phenotypes arise from distinct genomic compositions.

Additionally, migration patterns in painted ladies could not be associated with factors such as sex, wing size, or wing shape.

According to the scientists, so-called phenotypic plasticity might explain the different migration styles. "Phenotypic plasticity is the ability of an organism to change its phenotype—in this case, its engagement in long- or short-distance migration—in response to environmental conditions without altering its genetic makeup.
For instance, in summer, butterflies in Sweden might be prompted to migrate a long distance south across the Sahara due to the quick shift in day lengths or other seasonal cues. In contrast, butterflies in Southern France, where the days are longer, may not encounter those migratory cues and therefore only undertake short-distance journeys, staying in the Mediterranean area.

Megan S Reich et al. Isotope geolocation and population genomics in Vanessa cardui: Short- and long-distance migrants are genetically undifferentiated, PNAS Nexus (2025). DOI: 10.1093/pnasnexus/pgae586. academic.oup.com/pnasnexus/art … /4/2/pgae586/7994570

Part 2

Comment by Dr. Krishna Kumari Challa on February 5, 2025 at 11:17am

Decoding a butterfly's travel map: Scientists find globetrotting not in genes

Painted lady butterflies are world travelers. The ones we encounter in Europe fly from Africa to Sweden, ultimately returning to areas north and south of the Sahara. But what determines whether some butterflies travel long distances while others travel short distances? A group of scientists shows that the different migration strategies are shaped by environmental conditions rather than being encoded in the butterfly's DNA.

Researchers, alongside citizen science projects, have been trying to decode the butterfly travel map. Their interdisciplinary publication provides new insights.

The results are now published in PNAS Nexus.

The painted lady is a strikingly beautiful and colorful butterfly species. But what makes them particularly special is their incredible long-distance migrations.

These butterflies go on a yearly 10,000 km journey between Africa and Europe. They do so through a succession of generations, looking for the best breeding conditions for their offspring. Each individual travels in one section of the annual migratory cycle, with its offspring continuing their journey.

The colorful insects begin their grand voyage in spring, starting from Northwest Africa and flying over the Mediterranean Sea to Europe. Subsequent generations then make their way to Great Britain, even reaching the Arctic tundra of Sweden to spend the summer.

Until recently, it was believed that once the butterflies reach Sweden, they perish due to the colder climates that arise there at the end of summer. However, studies have shown that painted ladies return to warmer regions in autumn, confirming a circular migratory pattern. While some end up staying in the Mediterranean area, others travel back to Africa, even crossing the Sahara. But how come?

Researchers set out to understand this phenomenon.

They utilized isotope geolocation to estimate the geographic origin of each butterfly. The key principle of this method is that the isotopic makeup—or the stable isotopes—of the adult butterfly's wings mirrors the isotopic signature of the plants they ate as a caterpillar. 

 Isotopes are different forms of the same element, with identical chemical properties but slightly different atomic masses.

The researchers spent several years developing this technique, testing different isotopes, refining statistical approaches, and incorporating machine-learning techniques to enhance accuracy and resolution.

The analysis confirmed the diverse travel behavior among individuals: some took a long migration trip south from Scandinavia, crossing the Sahara, while others migrated a short distance, staying north of the desert in the Mediterranean region.

The scientists then used whole genome sequencing to compare DNA sequences of each individual. Interestingly, there was no genetic difference between short-trip and long-trip butterflies.

Part 1

Comment by Dr. Krishna Kumari Challa on February 5, 2025 at 10:25am

Climate change is overhauling marine nutrient cycles, scientists say

Computer models reveal how human-driven climate change will dramatically overhaul critical nutrient cycles in the ocean. In the Proceedings of the National Academy of Sciences,  researchers report evidence that marine nutrient cycles—essential for sustaining ocean ecosystems—are changing in unexpected ways as the planet continues to warm.

Model studies have suggested that when the ocean warms it gets more stratified, which can drain certain parts of the surface ocean of nutrients. 

Although models suggest a connection between ocean temperatures and surface ocean nutrients, this is the first study to confirm climate change's impacts on nutrient cycles.

The researchers  discovered that over the last half-century, there's been a major decline in phosphorus—a nutrient that plays a key role in the health of marine food webs—in southern hemisphere oceans.

There can be cascading effects up the food web, they say. Because plankton—microorganisms that form the bases of many marine food webs—rely on phosphorous as a food source. "When phytoplankton have less phosphorus, they become less nutritious, which can impair zooplankton and fish growth rates."

Surprisingly, concentrations of nitrate—a nutrient the team expected to decline—appear to remain steady. Nitrate is crucial for ecosystem functioning, so that it's not in decline is a good sign.

Nevertheless, nitrate concentrations may still decline in the future as the climate continues to change.

Skylar D. Gerace et al, Observed declines in upper ocean phosphate-to-nitrate availability, Proceedings of the National Academy of Sciences (2025). DOI: 10.1073/pnas.2411835122

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