3D microscopy clarifies understanding of body’s immune response to obesity

Researchers who focus on fat know that some adipose tissue is more prone to inflammation-related comorbidities than others, but the reasons why are not well understood. Thanks to a new analytical technique, scientists are getting a clearer view of the microenvironments found within adipose tissue associated with obesity. This advance may illuminate why some adipose tissues are more prone to inflammation — leading to diseases like type 2 diabetes, cancer and cardiovascular disorders — and help direct future drug therapies to treat obesity.

In a new study, University of Illinois Urbana Champaign bioengineering professors Andrew Smith and Mark A. Anastasio, molecular and integrative physiology professor Erik Nelson and nutritional sciences professor Kelly Swanson detail the use of the new technique in mice. The results are published in the journal Science Advances.

Inflammation in adipose tissue presents itself as round complexes of inflammatory tissue called crownlike structures. Previous studies have shown that body fat that contains these structures is associated with worse outcomes of obesity and related metabolic disorders, the study reports.

Previously, researchers were confined to the use of 2D slices of tissue and traditional microscopy, limiting what researchers could learn about them.

To get a better view, the team combined a special type of microscopy that uses a 3D sheet of light rather than a beam, a fat-clearing technique that renders tissue optically transparent, and deep-learning algorithms that help process the large amount of imaging data produced.

The researchers found that the crownlike appearances that gives these structures their name are, in reality, more like 3D shells or concentric spheres surrounding an empty core, Smith said.

“Using our new technique, we can determine the crownlike structures’ volume, the specific number of cells associated with them, as well as their size, geometry and distribution,” Smith said.

This ability led the team to discover that obesity tends to be associated with a prevalence of rare, massive crownlike structures that are not present in the lean state.

“These very large crownlike structures are clustered together and located in the center of the tissue,” Smith said. “And there is no way we could have analyzed this before using our new technique.”

Smith said the research may lead to new drug therapies and new ways to evaluate patients’ metabolic health.

“Right now, we know that some patients are overweight but metabolically healthy, while others are underweight and metabolically unhealthy,” Smith said. “We believe that having the ability to look deep into the microenvironments with fat tissue may unlock some of the reasons why this is.”

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Materials provided by University of Illinois at Urbana-Champaign, News Bureau. Original written by Lois Yoksoulian. Note: Content may be edited for style and length.

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New possibilities to prevent sudden cardiac death

Nearly a half-million people a year die from sudden cardiac death (SCD) in the U.S. — the result of malfunctions in the heart’s electrical system.

A leading cause of SCD in young athletes is arrhythmogenic cardiomyopathy (ACM), a genetic disease in which healthy heart muscle is replaced over time by scar tissue (fibrosis) and fat.

Stephen Chelko, an assistant professor of biomedical sciences at the Florida State University College of Medicine, has developed a better understanding of the pathological characteristics behind the disease, as well as promising avenues for prevention. His findings are published in the current issue of Science Translational Medicine.

Individuals with ACM possess a mutation causing arrhythmias, which ordinarily are non-fatal if managed and treated properly. However, Chelko shows that exercise not only amplifies those arrhythmias, but causes extensive cell death. Their only option is to avoid taking part in what should be a healthy and worthwhile endeavor: exercise.

“There is some awful irony in that exercise, a known health benefit for the heart, leads to cell death in ACM subjects,” Chelko said. “Now, we know that endurance exercise, in particular, leads to large-scale myocyte cell death due to mitochondrial dysfunction in those who suffer from this inherited heart disease.”

Several thousand mitochondria are in nearly every cell in the body, processing oxygen and converting food into energy. Considered the powerhouse of all cells (they produce 90 percent of the energy our bodies need to function properly), they also play another important role as a protective antioxidant.

As mitochondria fail to function properly, and myocyte cells in the heart die, healthy muscles are replaced by scar tissue and fatty cells. Eventually, the heart’s normal electrical signals are reduced to an erratic and disorganized firing of impulses from the lower chambers, leading to an inability to properly pump blood during heavy exercise. Without immediate medical treatment, death occurs within minutes.

Chelko’s research gets to the heart of the process involved in mitochondrial dysfunction.

“Ultimately, mitochondria become overwhelmed and expel ‘death signals’ that are sent to the nucleus, initiating large-scale DNA fragmentation and cell death,” Chelko said. “This novel study unravels a pathogenic role for exercise-induced, mitochondrial-mediated cell death in ACM hearts.”

In addition to providing a better understanding of the process involved, Chelko discovered that cell death can be prevented by inhibiting two different mitochondrial proteins. One such approach utilizes a novel targeting peptide developed for Chelko’s research by the National Research Council in Padova, Italy.

That discovery opens avenues for the development of new therapeutic options to prevent myocyte cell death, cardiac dysfunction and the pathological progression leading to deadly consequences for people living with ACM.

This research was funded by an American Heart Association Career Development Award.

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Materials provided by Florida State University. Original written by Doug Carlson. Note: Content may be edited for style and length.

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Covid-19: World’s first human challenge trials to start in UK

Healthy, young volunteers will be deliberately infected with a low dose of coronavirus.

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Hospital waiting list ‘may double to 10m by April’

There could be a surge in demand from delayed referrals and delays to treatment, a think tank warns.

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Covid: How will we know if the vaccine is working?

Deaths are falling faster for the over-80s – but does that mean the vaccine is working?

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Slow motion precursors give earthquakes the fast slip

At a glacier near the South Pole, earth scientists have found evidence of a quiet, slow-motion fault slip that triggers strong, fast-slip earthquakes many miles away, according to Cornell University research published in Science Advances.

During an earthquake, a fast slip happens when energy builds up underground and is released quickly along a fault. Blocks of earth rapidly slide against one another.

However, at an Antarctic glacier called Whillans Ice Plain, the earth scientists show that “slow slips” precede dozens of large magnitude 7 earthquakes. “We found that there is almost always a precursory ‘slow slip’ before an earthquake,” said lead author Grace Barcheck, research associate in Earth and Atmospheric Sciences at Cornell University.

Barcheck said that these slow-slip precursors — occurring as far as 20 miles away from the epicenter — are directly involved in starting the earthquake. “These slow slips are remarkably common,” she said, “and they migrate toward where the fast earthquake slip starts.”

Observations before several large tsunami-generating magnitude 8 and 9 earthquakes on subduction zone faults suggest a similar process may have occurred, according to Patrick Fulton, assistant professor and Croll Sesquicentennial Fellow in the Department of Earth and Atmospheric Sciences.

As these faults are mostly offshore and deep underwater, and because it is difficult to know when or where a large earthquake will occur, the start of large earthquakes is generally hard to observe.

To overcome these challenges, the scientists placed GPS sensors above an icy glacial fault at Whillans Ice Plain, where large magnitude 7 earthquakes occur nearly twice a day over a 60-mile-wide area of the glacier.

Within a period of two months in 2014, the group captured 75 earthquakes at the bottom of the Antarctic glacier. Data from GPS stations indicated that 73 — or 96% — of the 75 earthquakes showed a period of precursory slow motion.

The data from the GPS tracking stations and surface seismometers allowed the team to identify how the slow precursory slip triggers the fast earthquake slip.

“Our group was a little surprised to see so many precursors,” Barcheck said.

“In some cases, we can actually see the migration of the earthquake precursor towards where the earthquake begins.”

“Before we pored over the data, I thought that if we saw any precursors before the earthquakes, they would be rare and in the same place as the earthquake epicenter,” she said. “Instead, we found many slow-slip precursors — starting miles from the epicenters and migrating across the fault.”

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Materials provided by Cornell University. Original written by Blaine Friedlander. Note: Content may be edited for style and length.

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Covid: Extra 1.7m vulnerable added to shielding list

The move brings the total to 4m in England and means vaccinations will be prioritised more quickly.

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Radioactive bone cement may be safer in treating spinal tumors

A radioactive bone cement that’s injected into bone to provide support and local irradiation is proving to be a safer alternative to conventional radiation therapy for bone tumors, according to a study led by University of California, Irvine researchers.

The study shows that this brachytherapy cement can be placed into spinal bones to directly irradiate tumors without harming the spinal cord, and the radioactive material will stay localized in the bones, which promises to virtually eliminate side effects.

Lead researcher Joyce Keyak, UCI professor of radiological sciences, presented the results at the 2021 annual meeting of the Orthopaedic Research Society, which was held virtually Feb. 12-16.

Cancers that begin in the breast, prostate, lung, thyroid, kidney and other locations can spread to and erode bones, most commonly in the spine. Further complicating matters, normal radiation treatments for this problem can threaten the spinal cord and weaken the bones already compromised by the tumor’s erosion, increasing the risk of fracture.

Currently, multiple sessions of external beam radiation are used to treat cancer that has spread to the spine. This radiation causes unpleasant side effects (nausea, vomiting and diarrhea) and passes through the spinal cord, which often delays and limits treatment.

“Brachytherapy cement could be used without delay in a convenient, one-step, minimally invasive treatment to irradiate tumors,” Keyak said, “and would not irradiate the spinal cord or limit future treatment options.”

In animal and computational studies, the researchers evaluated the short-term safety of injecting brachytherapy cement into vertebrae; the possible migration of radioactivity into blood, urine or feces; the dose rate outside the injection site; and the radiation dose from phosphorus-32 emissions to the spinal cord and soft tissue.

At 17 weeks post-injection, physical examinations were all normal and no activity was detected in blood, urine or feces. The researchers found no evidence of the P-32 isotope in the circulating blood, no changes in blood work related to radioactivity and no neurological deficits.

“This localized treatment for bone tumors stays localized, and we did not see any effects outside the bone,” Keyak said. “This is important because traditional radiation therapy causes adverse effects such as nausea, vomiting and diarrhea.”

Bringing brachytherapy bone cement into being

Keyak and Dr. Harry Skinner, an orthopedic surgeon with St. Jude Heritage Medical Group, created the brachytherapy cement by infusing a common product of their trade, bone cement, with radioactive material already used in other treatments.

The brachytherapy bone cement does not have the same side effects as traditional radiation therapy, Keyak noted, because the injection directly targets the tumor and radiation doesn’t pass through other organs, such as the intestines or stomach. Previous studies also revealed that it can immediately reduce pain in the spine, potentially getting patients off strong painkillers that could carry additional side effects.

Normally, a bone cancer patient needs 10 or more sessions of radiation therapy. But with the brachytherapy bone cement, Keyak said, a single injection can provide an equivalent, targeted tumor treatment with significantly less threat to the spinal cord and nerves.

“You can have this procedure and be done with it,” she said. “And you can do it when tumors are smaller to prevent further bone and spinal cord damage, while limiting the pain and side effects that patients often feel.”

Keyak and Skinner have started a company, Bone-Rad Therapeutics, for their product and have licensed its intellectual property (four patents and one pending patent).

The next step, Keyak said, will be more animal studies, followed by an application for a clinical trial.

Mando Eijansantos, Katherine Rosecrance, Daniel Wong, Sayeh Feizi, Pranav Peddinti, Aleen Meldosian and Varun Sehgal of UCI and Clifford Les of Pedicaris Research in Birmingham, Michigan, also participated in the research.

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Genetic study of Lewy body dementia supports ties to Alzheimer’s and Parkinson’s diseases

In a study led by National Institutes of Health (NIH) researchers, scientists found that five genes may play a critical role in determining whether a person will suffer from Lewy body dementia, a devastating disorder that riddles the brain with clumps of abnormal protein deposits called Lewy bodies. Lewy bodies are also a hallmark of Parkinson’s disease. The results, published in Nature Genetics, not only supported the disease’s ties to Parkinson’s disease but also suggested that people who have Lewy body dementia may share similar genetic profiles to those who have Alzheimer’s disease.

“Lewy body dementia is a devastating brain disorder for which we have no effective treatments. Patients often appear to suffer the worst of both Alzheimer’s and Parkinson’s diseases. Our results support the idea that this may be because Lewy body dementia is caused by a spectrum of problems that can be seen in both disorders,” said Sonja Scholz, M.D., Ph.D., investigator at the NIH’s National Institute of Neurological Disorders and Stroke (NINDS) and the senior author of the study. “We hope that these results will act as a blueprint for understanding the disease and developing new treatments.”

The study was led by Dr. Scholz’s team and researchers in the lab of Bryan J. Traynor, M.D., Ph.D., senior investigator at the NIH’s National Institute on Aging (NIA).

Lewy body dementia usually affects people over 65 years old. Early signs of the disease include hallucinations, mood swings, and problems with thinking, movements, and sleep. Patients who initially have cognitive and behavioral problems are usually diagnosed as having dementia with Lewy bodies, but are sometimes mistakenly diagnosed with Alzheimer’s disease. Alternatively, many patients, that are initially diagnosed with Parkinson’s disease, may eventually have difficulties with thinking and mood caused by Lewy body dementia. In both cases, as the disease worsens, patients become severely disabled and may die within 8 years of diagnosis.

A growing body of evidence suggests genetics may play a role in the disorder and that some cases may be inherited. Scientists have found that some of these rare cases can be caused by mutations in the gene for alpha-synuclein (SNCA), the main protein found in Lewy bodies. Further studies have found that variants in the gene for apolipoprotein E (APOE), which is known to play a role in Alzheimer’s disease, may also play one in Lewy body dementia.

“Compared to other neurodegenerative disorders, very little is known about the genetic forces behind Lewy body dementia,” said Dr. Traynor. “To get a better understanding we wanted to study the genetic architecture of Lewy body dementia.”

To do this, they compared the chromosomal DNA sequences of 2,981 Lewy body dementia patients with those of 4,931 healthy, age-matched control participants. Samples were collected from participants of European ancestry at 44 sites: 17 in Europe and 27 across North America. The DNA sequencing was led by Clifton Dalgard, Ph.D., and researchers at The American Genome Center, a series of state-of-the-art laboratories at the Uniformed Services University of the Health Sciences and supported by the Henry M. Jackson Foundation for the Advancement of Military Medicine.

Initially, they found that the sequences of five genes from the Lewy body dementia patients were often different from those of the controls, suggesting that these genes may be important. It was the first time that two of the genes, called BIN1 and TMEM175, had been implicated in the disease. These genes may also have ties to Alzheimer’s and Parkinson’s diseases. The other three genes, SNCA, APOE, and GBA, had been implicated in previous studies, and thus, strengthened the importance of the genes in Lewy body dementia.

The researchers also saw differences in the same five genes when they compared the DNA sequences of another 970 Lewy body dementia patients with a new set of 8,928 control subjects, confirming their initial results.

Further analysis suggested that changes in the activity of these genes may lead to dementia and that the GBA gene may have a particularly strong influence on the disease. The gene encodes instructions for beta-glucosylceramidase, a protein that helps a cell’s recycling system break down sugary fats. The researchers found that both common and rare variants in the GBA gene are tied to Lewy body dementia.

“These results provide a list of five genes that we strongly suspect play a role in Lewy body dementia,” said Dr. Traynor.

Finally, to examine the apparent links between Lewy body dementia and other neurodegenerative diseases, the researchers further analyzed data from previous studies on Alzheimer’s and Parkinson’s disease. They found that the genetic profiles of the patients in this study had higher chances of suffering from either Alzheimer’s or Parkinson’s disease than the age-matched control subjects. These predictions held even after they lowered the potential impact of known Alzheimer’s and Parkinson’s disease-causing genes, like APOE and SNCA. Interestingly, the patient’s genetic risk profiles for Alzheimer’s disease, on the one hand, or Parkinson’s disease, on the other, did not overlap.

“Although Alzheimer’s and Parkinson’s disease are molecularly and clinically very different disorders, our results support the idea that the problems that cause those diseases may also happen in Lewy body dementia,” said Dr. Scholz. “The challenge we face in treating these patients is determining which specific problems are causing the dementia. We hope studies like this one will help doctors find precise treatments for each patient’s condition.”

To help with this effort, the team published the genome sequence data from the study on the database of Genotypes and Phenotypes (dbGaP), a National Library of Medicine website that researchers can freely search for new insights into the causes of Lewy body dementia and other disorders.

This study was supported in part by the NIH Intramural Research Programs at the National Institute of Neurological Disorders and Stroke (NS003154) and the National Institute on Aging (AG000935).

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