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Comment by Dr. Krishna Kumari Challa on April 27, 2025 at 12:39pm

Aging also transformed the APCs into a new type of stem cell called committed preadipocytes, age-specific (CP-As). Arising in middle age, CP-A cells actively churn out new fat cells, explaining why older mice gain more weight.

A signaling pathway called leukemia inhibitory factor receptor (LIFR) proved critical for promoting these CP-A cells to multiply and evolve into fat cells.

The scientists discovered that the body's fat-making process is driven by LIFR. While young mice don't require this signal to make fat, older mice do.

Guan Wang et al, Distinct adipose progenitor cells emerging with age drive active adipogenesis, Science (2025). DOI: 10.1126/science.adj0430

Part 2

Comment by Dr. Krishna Kumari Challa on April 27, 2025 at 12:38pm

Why our waistlines expand in middle age

Peoples' waistlines often expand in middle age, but the problem isn't strictly cosmetic. Belly fat accelerates aging and slows down metabolism, increasing their risk for developing diabetes, heart problems and other chronic diseases. Exactly how age transforms a six pack into a softer stomach, however, is murky.

Now preclinical research has uncovered the cellular culprit behind age-related abdominal fat, providing new insights into why our midsections widen with middle age.

The researchers discovered that aging triggers the arrival of a new type of adult stem cell and enhances the body's massive production of new fat cells, especially around the belly.

The scientists conducted a series of mouse experiments later validated on human cells.

They focused on white adipose tissue (WAT), the fatty tissue responsible for age-related weight gain.

While it's well-known that fat cells grow larger with age, the scientists suspected that WAT also expanded by producing new fat cells, meaning it may have an unlimited potential to grow.

To test their hypothesis, the researchers focused on adipocyte progenitor cells (APCs), a group of stem cells in WAT that evolve into fat cells.

They first transplanted APCs from young and older mice into a second group of young mice. The APCs from the older animals rapidly generated a colossal amount of fat cells.

When the team transplanted APCs from young mice into the older mice, however, the stem cells did not manufacture many new fat cells. The results confirmed that older APCs are equipped to independently make new fat cells, regardless of their host's age.

Using single-cell RNA sequencing, the scientists next compared APC gene activity in young and older mice. While barely active in young mice, APCs woke up with a vengeance in middle-aged mice and began pumping out new fat cells.

While most adult stem cells' capacity to grow wanes with age, the opposite holds true with APCs—aging unlocks these cells' power to evolve and spread. This is the first evidence that our bellies expand with age due to the APCs' high output of new fat cells.

Part 1

Comment by Dr. Krishna Kumari Challa on April 27, 2025 at 12:07pm

A Single-Celled Microbe Can Transform Into a Multicellular Creature

A single-celled microbe that revels in Earth's most hostile salt lakes has the remarkable ability to transform its mote of a body into multicellular tissue when the pressure's on.

Haloferax volcanii is a member of the often-overlooked archaea domain, which looks quite similar to bacteria and yet have more in common with our own domain, eukaryota. Multicellularity is common in eukaryotes and rare among bacteria, and as far as we know, H. volcanii is only the second archaeon found to take this multicellular leap.

H. volcanii has some impressive shape shifting techniques up its tiny sleeves to help it thrive in such extreme environments as the Dead Sea and the Great Salt Lake.

When H. volcanii's outer layer is pulled taut by physical forces, researchers found, the microbe takes on a form even more reminiscent of complex organisms: it goes multicellular.

To see what would happen under forces more similar to the microbe's natural habitat, the researchers next placed H. volcanii under pressure of more than 100 kPa, which is equivalent to conditions around ten meters underwater.

Not only did the organism flatten like a pancake, but over 12 hours its cells, each containing multiple sets of genetic information, grew larger and organized into a fused cluster resembling the tissue of multicellular organisms.

The microbes' flexible proteinaceous surface layer, more similar to animal cell membranes than the rigid cell walls of plants and fungi, seems key to its metamorphic ways.

https://www.science.org/doi/10.1126/science.adu0047

https://www.science.org/doi/10.1126/science.adw6689

Comment by Dr. Krishna Kumari Challa on April 26, 2025 at 12:23pm

Super stem cells become better versions of themselves by changing their diet

In a new study, researchers  have successfully created stem cells that are better at developing into other cell types, like a younger, fitter version of themselves—by changing their diet. These stem cells are better than normal stem cells at creating specialized cells like liver, skin or nerve cells, which is a core trait of stem cells.

Researchers showed that by changing their diet, the stem cells can rejuvenate and turn into 'super stem cells.' It forces them to metabolize their energy in a different way than they normally would, and that process essentially reprograms the stem cells.

The net result is that they behave like they are from an earlier stage of development, which enhances their ability to develop, or differentiate, into other types of cells.

Specifically, the researchers changed what type of sugar the stem cells have available in the medium they grow in. The cells use the sugar to generate energy.

"What is really striking is that they're not just better at differentiating, but they stay fit and keep healthy much better over time compared to stem cells in standard culture conditions. And it is done with a relatively simple method.

Altering metabolism programs cell identity via NAD+-dependent deacetylation, The EMBO Journal (2025). DOI: 10.1038/s44318-025-00417-0

Comment by Dr. Krishna Kumari Challa on April 25, 2025 at 1:10pm

UN warns vaccine-preventable diseases on the rise globally

Outbreaks of vaccine-preventable diseases such as measles, meningitis, and yellow fever are on the rise globally amid misinformation and cuts to international aid, the United Nations and the Gavi vaccine alliance warned this week.

Vaccines have saved more than 150 million lives over the past five decades. Funding cuts to global health have put these hard-won gains in jeopardy.

The increasing outbreaks around the world are "putting lives at risk and exposing countries to increased costs in treating diseases."

Measles, for example, is making an "especially dangerous comeback," with cases rising every year since 2021 and reaching an estimated 10.3 million in 2023, which is a 20% increase since 2022.

The organizations believe that the trend is likely to have continued into 2024 and 2025.

In the past 12 months, 138 countries have reported measles cases, with 61 experiencing large or disruptive outbreaks—the highest number observed in any 12-month period since 2019, according to the statement.

The joint statement was signed by the World Health Organization, the United Nations children's fund UNICEF, and Gavi, and was released Wednesday at the start of World Immunization Week, which runs April 24-30.

Cases of meningitis and yellow fever have also increased significantly in Africa in 2024, it said.

The spikes are taking place amid rising misinformation, population growth and humanitarian crisis.

https://www.who.int/news/item/24-04-2025-increases-in-vaccine-preve...

Comment by Dr. Krishna Kumari Challa on April 25, 2025 at 8:26am

Blocking a master regulator of immunity eradicates liver tumors in mice

A protein identified nearly 40 years ago for its ability to stimulate the production of red blood cells plays a  critical role in dampening the immune system's response to cancer.

Blocking the activity of the protein turns formerly "cold," or immune-resistant, liver tumors in mice into "hot" tumors teeming with cancer-fighting immune cells. When combined with an immunotherapy that further activates these immune cells against the cancer, the treatment led to complete regression of existing liver tumors in most mice. Treated animals lived for the duration of the experiment. In contrast, control animals survived only a few weeks.

This is a fundamental breakthrough in our understanding of how the immune system is turned off and on in cancer.

Although the work was completed in mice, there are strong indications that the protein, erythropoietin or EPO, plays a similar role in many types of human cancers.

 David Kung-Chun Chiu et al, Tumor-derived erythropoietin acts as an immunosuppressive switch in cancer immunity, Science (2025). DOI: 10.1126/science.adr3026. www.science.org/doi/10.1126/science.adr3026

Comment by Dr. Krishna Kumari Challa on April 24, 2025 at 11:00am

The current study, which included fewer than 50 participants, was built on previous research conducted in Italy. Researchers compared the levels of micronanoplastics found in the carotid arteries of three groups: people with healthy arteries; those with plaque but no symptoms; and those experiencing symptoms due to plaque buildup.

Researchers also compared plaques with low and high plastic levels to assess the effects of micronanoplastics on markers of inflammation, the gene activity of immune cells called macrophages and stem cells that help stabilize plaque.

The analysis found that the concentration of micronanoplastics in carotid arteries was:

16 times higher (895 micrograms/gram vs. 57 micrograms/gram) in plaque among people without symptoms compared to the levels found in artery walls of deceased tissue donors of similar age with no plaque; and
51 times higher (2,888 micrograms/gram vs. 57 micrograms/gram) in plaque from people who had experienced stroke, mini-stroke or temporary loss of vision due to blockage of blood flow to the retina, in comparison to samples from age-matched, deceased tissue donors.
Comparing high-plastic and low-plastic plaque levels, the analysis found:

no link between the amount of micronanoplastics and signs of sudden inflammation; and
differences in gene activity in plaque-stabilizing cells and less activity in anti-inflammatory genes of plaque macrophage immune cells.
"These findings indicate that the biological effects of micronanoplastics on fatty deposits are more complex and nuanced than simply causing sudden inflammation.

https://professional.heart.org/en/meetings/vascular-discovery-from-...

Part 2

Comment by Dr. Krishna Kumari Challa on April 24, 2025 at 10:59am

Tiny plastic particles found in artery-clogging plaque in the neck

People with plaque in the blood vessels of their neck have a higher amount of tiny plastic particles in those vessels compared to people with healthy arteries. This increase was significantly higher in people who had experienced a stroke, mini-stroke or temporary loss of vision due to clogged blood vessels, according to preliminary research presented at the American Heart Association's Vascular Discovery 2025 Scientific Ses..., April 22–25 .

Micronanoplastics are tiny pieces of plastic created in industrial processes or from larger plastic objects as they degrade in the ocean or the soil. Micronanoplastics are not uniform in size and are a mixture of micro and nano plastic sizes.

While microplastics are sometimes visible at less than 5 millimeters in size, nanoplastics are microscopic, less than 1,000 nanometers across. This makes them more easily dispersed and able to penetrate cells and tissues in living organisms. Researchers suggest that terminology should gradually transition to nanoplastics because that is more precisely what is being studied.

These types of plastics are commonly found in the environment, especially in ocean garbage patches. Over many years, these plastics break down, mix into the soil and water, and can build up in the food chain.

Many people think that micro and nanoplastics mainly come from using plastic utensils, cutting boards, packaging, water bottles and other plastic items. However, the main source is the food and water we eat and drink.

In 2024, researchers in Italy reported finding micronanoplastics in plaque from some people without symptoms who underwent surgery to remove carotid artery plaque.

Symptoms caused by carotid plaque buildup may include stroke, mini-stroke or temporary blindness. Followed for almost three years after surgery, people with micronanoplastics in their carotid plaque were significantly more likely to die or to have a non-fatal heart attack or stroke.

Part 1

Comment by Dr. Krishna Kumari Challa on April 24, 2025 at 10:40am

The world's biggest companies have caused $28 trillion in climate damage

The world's biggest corporations have caused $28 trillion in climate damage, a new study estimates as part of an effort to make it easier for people and governments to hold companies financially accountable.

A research team came up with the estimated pollution caused by 111 companies, with more than half of the total dollar figure coming from 10 fossil fuel providers: Saudi Aramco, Gazprom, Chevron, ExxonMobil, BP, Shell, National Iranian Oil Co., Pemex, Coal India and the British Coal Corporation.

The researchers figured that every 1% of greenhouse gas put into the atmosphere since 1990 has caused $502 billion in damage from heat alone, which doesn't include the costs incurred by other extreme weather such as hurricanes, droughts and floods. People talk about making polluters pay, and sometimes even take them to court or pass laws meant to rein them in. The study is an attempt to determine the causal linkages that underlie many of these theories of accountability.

Christopher W. Callahan et al, Carbon majors and the scientific case for climate liability, Nature (2025). DOI: 10.1038/s41586-025-08751-3

Comment by Dr. Krishna Kumari Challa on April 24, 2025 at 10:31am

Repair in mammals often proceeds through scarring, a process that rapidly seals wounds without restoring original tissue architecture. This may reflect an evolutionary trade-off in larger or more complex organisms, where fast tissue sealing through fibrosis can ensure immediate survival, even at the cost of long-term function or structural integrity.

Greater understanding of the requirements for regeneration in worms and other regenerating species brings science closer to the goal of one day reverse-engineering regenerative responses in therapeutic settings.

Clare L.T. Booth et al, Developmental onset of planarian whole-body regeneration depends on axis reset, Current Biology (2025). DOI: 10.1016/j.cub.2025.03.065

Part 2

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