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Comment by Dr. Krishna Kumari Challa on November 11, 2023 at 9:05am

Even more exciting is how closely the new study's results in mice appear to be reflected in human cells.

With a blood test, doctors can identify people who are at high-risk of developing type 1 diabetes months in advance of the death of their beta cells.

That may be a perfect timeframe for a treatment based on pharmacological inhibition of Atf6 or induction of LIF and other secreted proteins. If we can get there in time to protect these cells with transient senescence, the onset of diabetes might be prevented.

Hugo Lee et al, Stress-induced β cell early senescence confers protection against type 1 diabetes, Cell Metabolism (2023). DOI: 10.1016/j.cmet.2023.10.014

Part 2

Comment by Dr. Krishna Kumari Challa on November 11, 2023 at 9:03am

Relieving stress in insulin-producing cells protects against type 1 diabetes

Removing a gene that manages stress within insulin-producing beta cells draws helpful attention from the immune system, protecting mice predisposed to type 1 diabetes from developing the disease, a new  study shows.

The study also found that changes discovered in the modified mouse beta cells are also present in human beta cells that manage to survive the widespread beta-cell death that characterizes type 1 diabetes.

This gives the researchers hope that their findings, published in the journal Cell Metabolism, may point to a potential new treatment that could be administered very early in the development of diabetes. 

When we eat, our beta cells produce about 1 million molecules of insulin every minute to help maintain normal blood glucose levels. That is a big and stressful job, especially for a part of these beta cells called the endoplasmic reticulum.

The endoplasmic reticulum is like the cell's warehouse staff. It folds the insulin protein molecules that a beta cell produces, packing them for shipping to other parts of the body. If something goes wrong with the protein folding process, the shipping process backs up or even stops, stressing the endoplasmic reticulum. A stress-response gene called Atf6 perks up when a cell is struggling with unfolded proteins. But if Atf6 can't resolve the protein-folding problem, prolonged stress will eventually kill the cell.

Scientists bred a line of diabetes-predisposed mice without the Atf6 gene in their beta cells. Instead of meeting their typical fate, those mice were protected from diabetes. Analysis of the genes expressed by their beta cells suggested the cells entered a state called senescence far ahead of schedule.

Senescence is a period of the cell's life cycle in which it stops dividing and halts other normal cellular business. Senescing cells can cause problems for neighboring cells by releasing inflammatory messaging molecules that trigger an immune system response.

When researchers removed—knocked-out—the Atf6 gene in the beta cells in the pancreas of their mouse model of type 1 diabetes, and they did not become diabetic. Instead of dying off, these cells unexpectedly appear to go into an early senescence state that initiated a beneficial immune response and helped the cells survive an autoimmune attack.

DNA damage, stress and aging can kick off senescence, which can draw an immune system response that cleans up the senescent cells. If the immune system fails to clear these cells, they accumulate and cause chronic inflammation and disease.

The beta cells without Atf6 exhibit transient senescence and start releasing this group of proteins, including leukemia inhibitory factor, or LIF, that recruits protective immune cells called M2 macrophages.

Part 1

Comment by Dr. Krishna Kumari Challa on November 11, 2023 at 8:48am

Using bacteria to make lunar soil more fertile

A team of agronomists and biotechnicians  has found that adding bacteria to simulated lunar regolith increased the amount of phosphate in the soil for use by plants. In their study, published in the journal Communications Biology, the group added three types of bacteria to samples of volcanic material and then tested them for acidity and their ability to grow plants.

As several countries make plans to send humans back to the moon, they must address several issues—one of the most basic is figuring out a way to feed people working there for an extended period of time. The obvious solution is for workers to grow their own food. But that presents problems, as well, such as how to transport soil for growing edible plants from Earth to the moon.

Some have suggested that moon soil, known as lunar regolith, might be treated to make it amenable to plant growth. Last year, a team in the U.S. showed that it is possible to grow plants in lunar regolith by growing a small number of weeds called thale cress in real lunar soil samples. That test showed that lunar soil can work, but not well enough for plants to mature and produce food. In this new study, the research team found that adding microbes to lunar soil can improve its ability to host plant life. To test the possibility of using microbes such as bacteria to make lunar regolith more hospitable to plant life, the research team obtained samples of volcanic material from a mountain in China—testing showed it to be a reasonable stand-in for regolith. The researchers then added one of three types of bacteria to three test pots filled with the volcanic material: Pseudomonas fluorescens, Bacillus megaterium and Bacillus mucilaginosus. After cultivating the bacteria in the soil samples, the researchers tested the samples to see the effects. They found that the addition of all three types of bacteria had made the soil samples more acidic, which resulted in reducing the pH level of the soil. That dissolved the insoluble phosphate-containing minerals in the soil, which released phosphorus, making it available for plants.

Yitong Xia et al, Phosphorus-solubilizing bacteria improve the growth of Nicotiana benthamiana on lunar regolith simulant by dissociating insoluble inorganic phosphorus, Communications Biology (2023). DOI: 10.1038/s42003-023-05391-z

Comment by Dr. Krishna Kumari Challa on November 10, 2023 at 1:45pm

Engineered yeast breaks new record: a genome with over 50% synthetic DNA

Highly edited strain survives and replicates despite containing 7.5 artificial chromosomes.

Scientists have created a strain of brewer’s yeast (Saccharomyces cerevisiae) whose genome is more than half synthetic. Seven-and-a-half chromosomes were synthesized or stitched together in the laboratory. To make sure the genome was stable, biologists removed repetitive regions of DNA and sequestered all genes for transfer RNAs — essential for protein synthesis — in a single ‘neochromosome’. It’s a milestone for the Sc2.0 consortium, whose aim is to create yeast with a fully synthetic genome.

https://www.sciencedirect.com/science/article/pii/S0092867423011303...

https://www.cell.com/cell-genomics/fulltext/S2666-979X(23)00273-2?utm_source=Live+Audience&utm_campaign=3a61cb3609-briefing-dy-20231109&utm_medium=email&utm_term=0_b27a691814-3a61cb3609-50323416

Comment by Dr. Krishna Kumari Challa on November 10, 2023 at 1:33pm

Blood cancer treatment could be transformed by discovery

Comment by Dr. Krishna Kumari Challa on November 9, 2023 at 8:53am

This is how the scientists described their work:

After we prepared the hydrogel, we embedded photosynthetic—or sunlight-capturing—bacteria called cyanobacteria into the gel.

The cyanobacteria embedded in the material still needed to take in light and carbon dioxide to perform photosynthesis, which keeps them alive. The hydrogel was porous enough to allow that, but to make the configuration as efficient as possible, we 3D-printed the gel into custom shapes—grids and honeycombs. These structures have a higher surface-to-volume ratio that allow more light, CO₂ and nutrients to come into the material.
Like all other bacteria, cyanobacteria has different genetic circuits, which tell the cells what outputs to produce. Our team genetically engineered the bacterial DNA so that the cells created a specific enzyme called laccase.

The laccase enzyme produced by the cyanobacteria works by performing a chemical reaction with a pollutant that transforms it into a form that's no longer functional. By breaking the chemical bonds, it can make a toxic pollutant nontoxic. The enzyme is regenerated at the end of the reaction, and it goes off to complete more reactions.

 Debika Datta et al, Phenotypically complex living materials containing engineered cyanobacteria, Nature Communications (2023). DOI: 10.1038/s41467-023-40265-2

Comment by Dr. Krishna Kumari Challa on November 9, 2023 at 8:51am

Engineered 'living materials' could help clean up water pollution one day

Water pollution is a growing concern globally, with research estimating that chemical industries discharge 300–400 megatonnes (600–800 billion pounds) of industrial waste into bodies of water each year. As a team of materials scientists, we're working on an engineered "living material" that may be able to transform chemical dye pollutants from the textile industry into harmless substances.

Water pollution is both an environmental and humanitarian issue that can affect ecosystems and human health alike. We're hopeful that the materials we're developing could be one tool available to help combat this problem.
The "engineered living material" scientists have been working on contains programmed bacteria embedded in a soft hydrogel material.
The hydrogel that forms the base of the material has similar properties to Jell-O—it's soft and made mostly of water. Our particular hydrogel is made from a natural and biodegradable seaweed-based polymer called alginate, an ingredient common in some foods.

The alginate hydrogel provides a solid physical support for bacterial cells, similar to how tissues support cells in the human body. We intentionally chose this material so that the bacteria we embedded could grow and flourish.
Part 1

Comment by Dr. Krishna Kumari Challa on November 9, 2023 at 8:26am

Cheetahs become more nocturnal on hot days. Climate change may trigger fights among predators

Changing temperatures can impact the behavior patterns of large carnivore species and also the dynamics among species.

Cheetahs are usually daytime hunters, but the speedy big cats will shift their activity toward dawn and dusk hours during warmer weather, a new study finds.

Unfortunately for endangered cheetahs, that sets them up for more potential conflicts with mostly nocturnal competing predators such as lions and leopards, say the authors of research published recently in the journal Proceedings of the Royal Society B.

While cheetahs only eat fresh meat, lions and leopards will sometimes opportunistically scavenge from smaller predators.

Lions and leopards normally kill prey themselves, but if they come across a cheetah's kill, they will try to take it. The cheetahs will not fight the larger cats, they will just leave.

Hunting at different times of the day is one long-evolved strategy to reduce encounters between the multiple predator species. But the new study found that on the hottest days, when maximum daily temperatures soared to nearly 45 degrees Celsius (113 degrees Fahrenheit), cheetahs became more nocturnal—increasing their overlapping hunting hours with rival big cats by 16%.

There's a greater chance for more unfriendly encounters and less food for the cheetahs because of global warming. 

Kasim Rafiq et al, Increasing ambient temperatures trigger shifts in activity patterns and temporal partitioning in a large carnivore guild, Proceedings of the Royal Society B: Biological Sciences (2023). DOI: 10.1098/rspb.2023.1938

Comment by Dr. Krishna Kumari Challa on November 9, 2023 at 8:20am

 Willow bark extract has broad-spectrum antiviral effect

We need safe, sustainable antiviral options to treat the outbreaks of the future. Scientists  have now shown that an extract of willow bark—a plant that has already provided several medicines, including the precursor to modern aspirin—has a broad-spectrum antiviral effect in cell sample experiments.

The extract worked both on enveloped coronaviruses, which cause colds as well as COVID-19, and non-enveloped enteroviruses, which cause infections such as flu and meningitis. There are no clinically approved drugs that work against enteroviruses directly, so this extract could be a future game-changer.

The scientists had previously tested willow bark extract on enteroviruses, and found it was highly successful. In this new study, they expanded the remit of their research to look at additional kinds of virus and to try to understand the mechanism of the extract's action.

Willow (Salix spp.) bark hot extracts inhibit both enveloped and nonenveloped viruses: study on its anti-coronavirus and anti-enterovirus activities, Frontiers in Microbiology (2023). DOI: 10.3389/fmicb.2023.1249794

Comment by Dr. Krishna Kumari Challa on November 9, 2023 at 8:14am

This study showed that when participants received methylphenidate orally, the rate of dopamine increases peaked more than an hour after administration. Comparatively, when participants received an intravenous injection of methylphenidate, the rate of dopamine increases peaked much faster—within 5 to 10 minutes of the administration.

Through the fMRI, researchers observed that one brain region, the  ventromedial prefrontal cortex,  was less active after both oral and intravenous administration of the study drug. However, two brain regions, the dorsal anterior cingulate cortex and the insula, which are part of the brain's salience network, were activated only after receiving the injection of methylphenidate, the more addictive route of drug administration. These same areas of the brain were not activated after taking methylphenidate orally, the route with lower addiction potential. This finding was consistent among all 20 research participants.

The salience network attributes value to things in our environment and is important for recognizing and translating internal sensations—including the subjective effects of drugs. This research adds to a growing body of evidence documenting the important role that the salience network appears to play in substance use and addiction. For instance, studies have shown that people who experience damage to the insula, part of the brain's salience network, can have a complete remission of their addiction.

 P Manza, et al. Neural circuit selective for fast but not slow dopamine increases in drug reward, Nature Communications (2023). DOI: 10.1038/s41467-023-41972-6. www.nature.com/articles/s41467-023-41972-6

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