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Comment by Dr. Krishna Kumari Challa on November 11, 2025 at 8:19am

Neanderthal DNA helps explain how faces form

Every human face is unique, allowing us to distinguish between individuals. We know little about how facial features are encoded in our DNA, but we may be able to learn more about how our faces develop by looking at our ancient relatives, the Neanderthals. Neanderthal faces were quite distinctive from our own, with large noses, pronounced brows and a robust lower jaw.

Now, scientists are using the DNA of our extinct distant relatives to learn more about how faces develop and evolve.

Published in the journal Development, they show how a region of Neanderthal DNA is better at activating a jaw-forming gene than the human counterpart, revealing one potential reason for Neanderthal's larger lower jaws.

Scientists have sequenced the Neanderthal genome using DNA extracted from ancient bone. The Neanderthal genome is 99.7% identical to the genome of modern-day humans and the differences between species are likely responsible for altering appearance. Both human and Neanderthal genomes consist of about 3 billion letters that code for proteins and regulate how genes are used in the cell, which makes finding regions that impact appearance like looking for a needle in a haystack.

But still they decided on a region of the genome that is linked to Pierre Robin sequence, a syndrome in which the lower jaw is disproportionately small. Some individuals with Pierre Robin sequence have large deletions or DNA rearrangements in this part of the genome that change face development and limit jaw formation. They predicted that smaller differences in the DNA might have more subtle effects on face shape.

By comparing human and Neanderthal genomes, the team found that in this region, roughly 3000 letters in length, there were just three single-letter differences between the species. Although this region of DNA doesn't contain any genes, it regulates how and when a gene is activated, specifically a gene called SOX9, a key coordinator of the process of face development.

To demonstrate that these Neanderthal-specific differences are important for the development of the face, the researchers needed to show that the Neanderthal region could activate genes in the right cells at the right time as the embryo develops.

The researchers simultaneously inserted the Neanderthal and human versions of the region into the DNA of zebrafish and programmed the zebrafish cells to produce different colors of fluorescent protein depending on whether the human or Neanderthal region was active.

Watching the zebrafish embryos develop, the researchers found that both the human and Neanderthal regions were active in the zebrafish cells that are involved in forming the lower jaw and the Neanderthal region was more active than the human version.

This led them to think about what the consequences of these differences could be, and how to explore these experimentally.

Knowing that the Neanderthal sequence was more powerful at activating genes, the researchers then asked if the resulting increased activity of its target, SOX9, might change the shape and function of the adult jaw. To test this theory, they provided the zebrafish embryos with extra SOX9 and found that cells that contribute to forming the jaw occupied a larger area.

This research shows that by studying extinct species we can learn how our own DNA contributes to face variation, development and evolution.

Kirsty Uttley et al, Neanderthal-derived variants increase SOX9 enhancer activity in craniofacial progenitors that shape jaw development, Development (2025). DOI: 10.1242/dev.204779

Comment by Dr. Krishna Kumari Challa on November 10, 2025 at 8:05am

We're Still Evolving: Human Arms Keep Growing an Extra Artery

Subtle shifts in our anatomy today demonstrate how unpredictable evolution can be. Take something as mundane as an extra blood vessel in our arms, which, going by current trends, could be commonplace within just a few generations.

An artery that temporarily runs down the center of our forearms while we're still in the womb isn't vanishing as often as it used to, according to a study published in 2020 by researchers.

That means there are more adults than ever with what amounts to an extra channel of vascular tissue flowing under their wrist.

Since the 18th century, anatomists have been studying the prevalence of this artery in adults and our study shows it's clearly increasing.

The prevalence was around 10 percent in people born in the mid-1880s compared to 30 percent in those born in the late 20th century, so that's a significant increase in a fairly short period of time, when it comes to evolution

https://onlinelibrary.wiley.com/doi/10.1111/joa.13224

Comment by Dr. Krishna Kumari Challa on November 10, 2025 at 7:59am

First ever atlas of brain development

First-ever atlas of brain development shows how stem cells turn into neurons

A collection of studies that chart how mammalian brain cells grow and differentiate is a ‘very valuable’ tool for neuroscientists.

Scientists have created the most detailed maps yet of how our brains differentiate from stem cells during embryonic development and early life. In a collection of five papers, they tracked hundreds of thousands of early brain cells in the cortices of humans and mice, and captured with unprecedented precision the molecular events that give rise to a mixture of neurons and supporting cells. It's really the initial first draft of any ‘cell atlases’ for the developing brain.

https://www.nature.com/articles/d41586-025-03641-0?utm_source=Live+...

Comment by Dr. Krishna Kumari Challa on November 8, 2025 at 11:15am

Good Social Interactions Slow Cancer Via an Anxiety-Reducing Neural Circuit

Just an hour of socializing per day helped mice fight tumors. Now scientists have traced the brain circuitry that turns companionship into a cancer-fighting signal.

In the 1970s and ‘80s, scientists began noticing that people who had few or poor social relationships had a higher risk of developing illnesses and all-cause mortality. A slew of follow-up studies suggested that social support could protect people from pathological conditions like arthritis, alcoholism, depression, and even death. This link holds true for cancer as well. Upon analyzing disease progression and survival rates in thousands of breast cancer patients, researchers observed a negative impact of social isolation and a positive impact of interpersonal connections on prognosis.

One of the popular theories explaining these effects states that being social eases anxiety, a well-established driver of tumor growth, and consequently inhibits cancer progression. But how exactly does the body sense these stimuli and pump the brakes on cancer?

In a recent study published in Neuron, researchers uncovered the neural circuitry that drives the therapeutic effects of social connections on cancer, in mice. It demonstrates a real biological pathway by which this nebulous subject of social interaction can influence cancer.

That means that now it's technically targetable, by drugs or by neuromodulation techniques, when before, we wouldn't even know what to target or if there was something to target.

 These findings establish a new paradigm for how psychosocial factors influence cancer via neural circuits and could potentially lead to therapies that complement existing treatments.

Wen HZ, et al. Social interaction in mice suppresses breast cancer progression via... Neuron. 2025;113(20)3374-3389.e9.

Comment by Dr. Krishna Kumari Challa on November 8, 2025 at 9:09am

Urolithin A nudges aging immune cells toward a youthful profile in 28 days

An international research team focused on aging reports that urolithin A at 1,000 mg per day shifted human immune profiles toward a more naive-like, less exhausted CD8⁺ state and increased fatty acid oxidation capacity, with additional functional gains.

Urolithin A is a metabolite produced by gut bacteria after breaking down ellagic acid from certain foods, such as pomegranates and walnuts. While produced naturally through microbial digestion, it is in much smaller quantities than available as a supplement or used in the study.

Aging bodies face reduced production of mature T cells, shrinking naive T cell pools and chronic low-grade inflammation. Mitochondrial dysfunction and waning autophagy sit at the core of these shifts, with mitophagy failure linked to immune dysregulation and disease.

Preclinical evidence identified urolithin A as a potent inducer of mitophagy, clearing out damaged mitochondria, in rodents and humans. Previous clinical trials have reported improved physical performance following supplementation.

Improving mitochondrial quality control with a positive influence on immune function would represent a turning back of the aging biological clock, if it can have a meaningful and prolonged effect in humans.

Conclusion: Short-term urolithin A supplementation modulated human immune cell composition and metabolism and improved selected functional responses, supporting the body's potential to counteract age-related immune decline.

Dominic Denk et al, Effect of the mitophagy inducer urolithin A on age-related immune decline: a randomized, placebo-controlled trial, Nature Aging (2025). DOI: 10.1038/s43587-025-00996-x

A natural compound revitalizes the aging human immune system, Nature Aging (2025). DOI: 10.1038/s43587-025-01012-y

Comment by Dr. Krishna Kumari Challa on November 8, 2025 at 8:44am

Coordinated brain network activity during emotional arousal may explain vivid, lasting memories

Past psychology studies suggest that people tend to remember emotional events, such as their wedding, the birth of a child or traumatic experiences, more vividly than neutral events, such as a routine professional meeting. While this link between emotion and the recollection of past events is well-established, the neural mechanisms via which emotional states strengthen memories remain poorly understood.

So researchers now carried out a study aimed at better understanding these mechanisms. Their findings, published in Nature Human Behaviour, suggest that emotional states facilitate the encoding of memories by increasing communication between networks of brain regions.

Emotional experiences tend to be 'sticky,' meaning that they endure in our memories and shape how we interpret the past, engage with the present, and anticipate the future. 

The primary objective of the recent study 's to study the neural processes that make emotional memories become more persistent. To do this, they used brain imaging techniques combined with computational models that can analyze and generate texts, known as natural language processing (NLP) models.

The analyses carried out by the researchers revealed that when participants were emotionally aroused, the activity of various brain networks was more coordinated than when they were in neutral or mild emotional states. Notably, this greater coordination between brain networks was found to predict how well participants remembered the scenes that they viewed during the experiment.

It is more like an orchestra, where different sections work together to create a unified performance, with arousal serving as a conductor that coordinates their activity. This perspective suggests that whether we remember an emotional memory depends not only on the strength of activity in any single region, but also on how effectively different systems communicate and share information.

Overall, the results of this research team's analyses suggest that emotions strengthen the synchronization between brain networks, which in turn supports the encoding of memories. Their paper thus introduces a new way of thinking about emotional memories, suggesting that it is supported by the coordinated activity of various brain regions.

 Jadyn S. Park et al, Emotional arousal enhances narrative memories through functional integration of large-scale brain networks, Nature Human Behaviour (2025). DOI: 10.1038/s41562-025-02315-1.

Comment by Dr. Krishna Kumari Challa on November 7, 2025 at 10:01am

Carcinogenic preservatives are used in many processed meats such as bacon and ham. These preservatives, known as nitrites, are added to keep meat looking fresh and pink, enhance flavor and prevent spoilage. But they are now implicated in tens of thousands of cancer cases every year in the UK.
The danger comes from the way nitrites behave once eaten. Inside the body, they can turn into compounds called nitrosamines, which are potent carcinogens that damage DNA, the genetic material that controls how cells grow and divide.

These nitrosamines can attach themselves to DNA in the liver, forming DNA adducts, which are small chemical bonds that stick to the genetic material and distort its structure. This damage can cause genetic errors that, over time, build up and allow cells to divide uncontrollably, forming tumors, particularly in the colon.

Nitrosamines can also trigger stress within cells by creating harmful molecules called reactive oxygen species, which cause additional DNA damage. This combination of oxidative stress and genetic instability can help cancer develop and spread.

https://theconversation.com/the-case-for-a-cancer-warning-on-your-b...

Comment by Dr. Krishna Kumari Challa on November 7, 2025 at 9:59am

PFAS may be eliminated from the body faster with certain medicines, study suggests

Certain medicines can cause the environmental toxin PFAS to be eliminated from the body faster, according to a study from the University of Gothenburg. The findings highlight one more medicine as effective, but whether it brings health benefits is still unclear.

The study, published in the journal Environment International, is based on controlled studies carried out in Ronneby in Blekinge, where drinking water from a municipal water treatment plant previously contained very high levels of the environmental toxin PFAS.

The discovery was made in 2013, and the contamination was found to have originated from aqueous film-forming foam that had been used for decades during fire drills at the Air Force Wing F17 in Ronneby. The contaminated water was immediately replaced by clean water from another water treatment plant in the municipality.

A previous survey has shown that many residents had highly elevated levels of PFAS in their blood. It can take many years for PFAS to be eliminated from the body, but this varies widely between individuals. The reasons for this variation are not yet fully understood.

The study involved 10 subjects, aged 25 to 47, who were tested with different medicines to lower the levels of PFAS in their bodies. Participants were their own control subjects by taking a medication for a 12-week period, and were without medication for the same length of time.

The PFAS substances studied were more rapidly eliminated from the body by two of the medicines: the cholesterol-lowering drug cholestyramine, which confirms the findings of a Danish study last year; and the related medicine colesevelam, where the effect on elimination has not previously been demonstrated.

During the 12 weeks without medication, the level of the studied PFAS substances fell by a few percent, whereas the period with medication gave reductions of at most 40% for one of the PFAS substances.

Axel G. Andersson et al, Serum, urinary and fecal concentrations of perfluoroalkyl substances after interventions with cholestyramine/colesevelam and probenecid – cross-over trials in Ronneby, Sweden, Environment International (2025). DOI: 10.1016/j.envint.2025.109794

Comment by Dr. Krishna Kumari Challa on November 7, 2025 at 9:59am

New insights on gut microbes that prevent formation of cancer-causing compounds

Nitrogen metabolism of gut bacteria can provide health benefits. Specifically, gut microbes metabolize dietary nitrates and nitrites and prevent the formation of cancer-causing compounds called nitrosamines. New research published in The FEBS Journal sheds light on these processes and pinpoints which types of bacteria are most important.

Investigators found that Escherichia coli—and to a lesser extent, species of the genera Lactobacillus, Bacteroides and Phocaeicola—can efficiently metabolize different forms of nitrogen, thus preventing carcinogenic nitrosamine formation.

They also demonstrate that this bacterial processing is critical to enable microorganisms to survive and colonize the intestinal tract, likely preventing harmful changes in the composition of the gut microbiota.

The findings highlight the importance of the gut microbiota in preventing the formation of harmful nitrogen metabolites, potentially decreasing the risk of certain cancers. The study also illustrates how the microbiota facilitates crosstalk between our diet and the gut, thus having important implications for both health and disease.

 Distribution and activity of nitrate and nitrite reductases in the microbiota of the human intestinal tract, FEBS Journal (2025). DOI: 10.1111/febs.70299

Comment by Dr. Krishna Kumari Challa on November 7, 2025 at 9:48am

Stem cells derived from fatty tissue successfully repair spinal fractures in rats

 Researchers used stem cells extracted from adipose, the body's fatty tissue, to treat spine fractures in rats similar to those caused by osteoporosis in humans. These cells offer the advantages of being easy to collect, even from elderly individuals, and causing little stress to the body, suggesting a noninvasive way of treating bone diseases.

Osteoporosis is a disease that causes bones to become brittle and prone to fractures. 

Among osteoporosis-related fractures, compression fractures of the spine, known as osteoporotic vertebral fractures, are the most common type of fracture and pose a serious problem, leading to a need for long-term care and a significant decline in quality of life.

Stem cells taken from adipose tissue (ADSCs) are a possible solution to this problem. These cells are multipotent, meaning that they can be differentiated into many different cell types.

Forming ADSCs into three-dimensional spherical clusters, known as spheroids, has been reported to enhance their ability to repair tissue. When these spheroids are pre-differentiated toward bone cells, their capacity to promote bone healing is enhanced.

The ADSCs were developed into bone-differentiated spheroids and combined with β-tricalcium phosphate, a material widely used for bone reconstruction, to successfully treat rats with spinal fractures.

Bone regeneration and strength were significantly improved in rats transplanted with the complex. They also found that the genes involved in bone formation and regeneration were also activated.

This study has revealed the potential of bone differentiation spheroids using ADSCs for the development of new treatments for spinal fractures.

Since the cells are obtained from fat, there is little burden on the body, ensuring patient safety.

Yuta Sawada et al, Development of a new treatment for osteoporotic vertebral fractures using adipose-derived stem cell spheroids, Bone & Joint Research (2025). DOI: 10.1302/2046-3758.1410.bjr-2025-0092.r1

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