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March 12th, 2018

Revolutionary Technique Allows Imaging of All Cells in Entire Regions of Living Brain

Until now, existing microscopy methods to explore living brain tissue have been limited to imaging previously labeled cells only. Yet, owing to technical limitations, not all the cells in a specific region of the brain can be labeled simultaneously, and this has restricted the way we see, and therefore understand, how brain cells, which are highly interconnected, are organized and interact with each other. Dr. Jan Tønnesen, researcher in the Ramón y Cajal Programme at the UPV/EHU-University of the Basque Country’s Department of Neurosciences, and who works at the ACHUCARRO Centre (Achucarro Basque Center for Neuroscience) located in the Basque town of Leioa, is one of the authors of a piece of work published in the February 22, 2018 issue of Cell. The open-access article describes a new microscopy technique known as SUSHI designed to improve the imaging of cells in living brain tissue. The article is titled “Super-Resolution Imaging of the Extracellular Space in Living Brain Tissue.” The new SUSHI (Super-resolution Shadow Imaging) technique allows the tiny space full of liquid surrounding brain cells to be labeled in one sweep, thus obviating the need to individually label all the cells that one is intending to analyze. Given that this "label" also remains outside the cells, a kind of negative image akin to the film used in old cameras is produced. So, the negative image contains the same information about the brain cells as its corresponding positive image, but, thanks to the fact that the labeling procedure is more straightforward, it is much easier to obtain this image and all the information contained in it.

New Treatment for Chronic Neuropathic Pain Targeting FLT3 Molecule Suggested by Mouse Study

Neuropathic pain is a chronic illness affecting 7-10% the population in France and for which there is no effective treatment. Researchers at the Institute for Neurosciences of Montpellier (INSERM/Université de Montpellier) and the Laboratory for Therapeutic Innovation (CNRS/Université de Strasbourg) have uncovered the mechanism behind the appearance and continuation of pain. Based on their discovery, an innovative treatment was developed which produces, in animal subjects, an immediate, robust, and long-lasting therapeutic effect on pain symptoms. This study was published online on March 12, 2018 in Nature Communications. The open-access article is titled “Inhibition of Neuronal FLT3 Receptor Tyrosine Kinase Alleviates Peripheral Neuropathic Pain in Mice.” French researchers have just revealed the unexpected role played by the molecule FLT3 (FMS-like tyrosine kinase 3) in chronic pain, known for its role in different blood functions and produced by the hematopoietic stem cells that generate all blood cells. Neuropathic pain is caused by a lesion in peripheral nerves due to diseases such as diabetes, cancer, or shingles, or to accident- or surgery related trauma. In this study, researchers showed that immune cells in the blood which flood the nerve at the site of the lesion synthesize and release another molecule, FL, which binds with and activates FLT3, triggering a chain reaction in the sensory system, causing pain. It was revealed that FLT3 induces and maintains pain by acting far upstream on other components in the sensory system that are known for making pain chronic (known as "chronicization").

March 11th

Top-Line Data Demonstrate Significant Reductions of Disease-Causing Mutant Huntingtin Protein in People with Huntington's Disease

Ionis Pharmaceuticals, Inc. (NASDAQ: IONS), a leader in antisense therapeutics, announced, on March 1, 2018, the presentation of positive top-line data from a completed Phase 1/2 study of IONIS-HTTRx (RG6042) in people with early-stage Huntington's disease (HD) at the 13th Annual CHDI HD conference (http://chdifoundation.org/13th-annual-hd-therapeutics-conference/) (February 26-March 1) in Palm Springs, California. The data demonstrate that IONIS-HTTRx (RG6042) is the first drug in development to lower the disease-causing protein in people with HD. HD is a rare, progressive, neurodegenerative disease caused by genetic mutation in the huntingtin gene, which results in the production of a toxic protein, the mutant huntingtin (mHTT) protein, which gradually destroys neurons in the brain resulting in deterioration in mental abilities and physical control. Ionis designed IONIS-HTTRx (RG6042), a Generation 2+ antisense drug, to specifically reduce the production of all forms of the huntingtin protein, including normal and mHTT. "For nearly twenty years, I have seen many families devastated from losses to this progressive neurodegenerative disease. With IONIS-HTTRx (RG6042), the HD community has new hope for a therapy that can reduce the cause of HD, and therefore, may slow the progression and potentially prevent the disease in future generations, which is truly groundbreaking," said Dr. Sarah Tabrizi, Professor of Clinical Neurology, Director of the University College London's Huntington's Disease Centre and the global lead investigator on the study.

March 8th

Exosomal MicroRNA 876-3p Predicts and Protects Against Severe Bronchopulmonary Dysplasia in Extremely Premature Infants

Extremely low birth-weight babies are at risk for a chronic lung disease called bronchopulmonary dysplasia, or BPD. This condition can lead to death or long-term disease, but clinical measurements are unable to predict which of the tiny infants — who get care in hospital intensive-care units and often weigh just one and a half pounds — will develop BPD. University of Alabama at Birmingham (UAB) researchers now report discovery of a strong predictive biomarker for BPD, and they show a role for the biomarker in the pathogenesis of this neonatal lung disease. These results open the path to possible future therapies to prevent or lessen BPD, which is marked by inflammation and impaired lung development. This biomarker could also help neonatologists plan optimal management and risk stratification of their tiny patients, and it could guide targeted enrollment of high-risk infants into randomized trials of potentially novel treatment strategies. The UAB work, published online on March 8, 2018 in the journal JCI Insight, is an example of “bedside to bench” research. It began with prospective studies of extremely premature infants to identify potential biomarkers, and then proceeded to lab experiments using animal models and cells grown in culture to learn how the biomarker functions in disease progression. The study was led by Charitharth Vivek Lal, MD, Assistant Professor in the UAB Pediatrics Division of Neonatology, and it builds upon Dr. Lal’s 2016 report that early microbial imbalance in the airways of extremely premature infants is predictive for development of BPD.

March 1st

Genetics of Human Host Plays Very Minor Role in Determining Microbiome Variation; Diet & Lifestyle Are Most Dominant Factors Shaping Microbiome Composition, New Study Suggests; Modification of Microbiome May Have Major Influence on Health

The question of nature versus nurture extends to our microbiome - the personal complement of mostly-friendly bacteria we carry around with us. Study after study has found that our microbiome affects nearly every aspect of our health; and its microbial composition, which varies from individual to individual, may hold the key to everything from weight gain to moods. Some microbiome researchers had suggested that this variation begins with differences in our genes; but a large-scale study conducted at the Weizmann Institute of Science in Israel challenges this idea and provides evidence that the connection between microbiome and health may be even more important than we thought. Indeed, the working hypothesis has been that genetics plays a major role in determining microbiome variation among people. According to this view, our genes determine the environment our microbiome occupies, and each particular environment allows certain bacterial strains to thrive. However, the Weizmann researchers were surprised to discover that the host's genetics plays a very minor role in determining microbiome composition - accounting for only about 2% of the variation between populations. The research was led by research student Daphna Rothschild, Dr. Omer Weissbrod, and Dr. Elad Barkan from the lab of Professor Eran Segal of the Computer Science and Applied Mathematics Department, together with members of Professor Eran Elinav's group of the Immunology Department, all at the Weizmann Institute of Science. The researchers’ findings, which were published on February 28, 2018 in Nature, were based on a unique database of around 1,000 Israelis who had participated in a longitudinal study of personalized nutrition.

February 28th

Single Non-Coding Nucleotide Difference Renders African Salmonella Variant Highly Lethal

Scientists at the University of Liverpool have identified a single genetic change in Salmonella that is playing a key role in the devastating epidemic of bloodstream infections currently killing approximately 400,000 people each year in sub-Saharan Africa. Invasive non-typhoidal Salmonellosis (iNTS) occurs when Salmonella bacteria, which normally cause gastrointestinal illness, enter the bloodstream and spread through the human body. The African iNTS epidemic is caused by a variant of Salmonella typhimurium (ST313) that is resistant to antibiotics and generally affects individuals with immune systems weakened by malaria or HIV. In a new study published online on February 27, 2018 in PNAS, a team of researchers led by Professor Jay Hinton at the University of Liverpool have identified a specific genetic change, a single-nucleotide polymorphism (SNP), that helps the African Salmonella to survive in the human bloodstream. The open-access article is titled “Role of a Single Noncoding Nucleotide in the Evolution of an Epidemic African Clade of Salmonella.” Professor Hinton explained: "Pinpointing this single letter of DNA is an exciting breakthrough in our understanding of why African Salmonella causes such a devastating disease, and helps to explain how this dangerous type of Salmonella evolved." SNPs represent a change of just one letter in the DNA sequence and there are thousands of SNP differences between different types of Salmonella. Until now, it has been hard to link an individual SNP to the ability of bacteria to cause disease. Using a type of RNA analysis called transcriptomics, the scientists identified SNPs that affected the level of expression of important Salmonella genes.

Study Suggests New Strategy Against Vascular Disease in Diabetes--Insulin-Mimicking Peptide Not Only Lowers Blood Sugars, But Also Slows Progression of Atherosclerosis In Mouse Model

Recent findings suggest a novel approach for protecting people with diabetes from their higher risk of advanced blood vessel disease, which sets the stage for early heart attacks and strokes. Cardiovascular problems from atherosclerosis - plaque-like lesions forming in artery walls - are the major cause of death in people with type 2 diabetes and metabolic syndrome. People with metabolic syndrome exceed the normal range for several clinical measurements: blood pressure, blood sugar levels, harmful lipids, body mass index, and belly fat. The researchers studied mice with metabolic syndrome. The mice were obese and had impaired glucose tolerance, a sign of pre-diabetes. In the study, an insulin-mimicking synthetic peptide called S597 was shown to both reduce blood sugar levels and slow the progression of atherosclerotic lesions. Insulin, even when it controls diabetes, does not prevent atherosclerosis. The findings were published in the February 26, 2018 issue of Diabetes. The article is titled “A Novel Strategy to Prevent Advanced Atherosclerosis and Lower Blood Glucose in a Mouse Model of Metabolic Syndrome.” The senior author is Karin E. Bornfeldt, University of Washington (UW) School of Medicine Professor of Medicine, Division of Metabolism, Endocrinology and Nutrition. Jenny Kanter, UW Research Assistant Professor of Medicine, was the lead author. They are scientists at the UW Medicine Diabetes Institute. The study was conducted as a research collaboration with Novo Nordisk A/S. Although S597 is composed of a single chain of amino acids and looks nothing like insulin, S597 can still activate insulin receptors. But, unlike insulin, it's more selective in what it turns on inside the cells.

February 26th

Study Unravels Novel Pathway That Regulates Innate and Adaptive Immunity Via Mast Cells, Exclusively, and Underscores Therapeutic Potential of NAD+ in Myriad Diseases

Researchers at Brigham and Women's Hospital (BWH) in Boston have discovered a new cellular and molecular pathway that regulates CD4+ T cell response--a finding that may lead to new ways to treat diseases that result from alterations in these cells. The discovery, published online on February 19, 2018 in the Journal of Allergy and Clinical Immunology, shows that administering oxidized nicotinamide adenine dinucleotide (NAD+), a natural molecule found in all living cells, shuts off the capacity of dendritic cells and macrophages to dictate CD4+ T fate. Researchers found that NAD+ administration regulated CD4+ T cells via mast cells (MCs), cells that have been mainly described in the context of allergy, exclusively. "This is a novel cellular and molecular pathway that is distinct from the two major pathways that were previously known. Because it is distinct and because it has the ability to regulate the immune system systemically, we can use it as an alternative to bypass the current pathways," said Abdallah ElKhal, PhD, BWH Department of Surgery, senior study author. The open-access article is titled “Mast Cells Regulate CD4+ T Cell Differentiation in Absence of Antigen Presentation.” CD4+ T helper cells and dendritic cells play a central role in immunity. Alterations or aberrant dendritic cells and T cell responses can lead to many health conditions including autoimmune diseases, infections, allergy, primary immunodeficiencies, and cancer. As of today, two major pathways have been described to regulate CD4+ T cell response. The first pathway was described by Peter C. Doherty and Rolf M. Zinkernagel (1996 Nobel prize winners) showing the requirement of MHC-TCR signaling machinery.

February 25th

Better Diet May Ease Depression

People who eat vegetables, fruit, and whole grains may have lower rates of depression over time, according to a preliminary study released on February 25, 2018 and that will be presented at the American Academy of Neurology's 70th Annual Meeting in Los Angeles, April 21 to 27, 2018 (https://www.aan.com/conferences-community/annual-meeting/registration-an...). The study found that people whose diets adhered more closely to the Dietary Approaches to Stop Hypertension (DASH) diet were less likely to develop depression than people who did not closely follow the diet. In addition to fruit and vegetables, the DASH diet recommends fat-free or low-fat dairy products and limits foods that are high in saturated fats and sugar. Studies have shown health benefits such as lowering high blood pressure and bad cholesterol (LDL), along with lowering body weight. "Depression is common in older adults and more frequent in people with memory problems, vascular risk factors such as high blood pressure or high cholesterol, or people who have had a stroke," said study author Laurel Cherian, MD, of the Rush University Medical Center in Chicago and a member of the American Academy of Neurology. "Making a lifestyle change such as changing your diet is often preferred over taking medications, so we wanted to see if diet could be an effective way to reduce the risk of depression." For the study, 964 participants with an average age of 81 were evaluated yearly for an average of six-and-a-half years. They were monitored for symptoms of depression such as being bothered by things that usually didn't affect them and feeling hopeless about the future.

Lizard Genome Sequencing Reveals Molecular Genetic Evidence for Rapid Evolution

Lizards have special superpowers. While birds can regrow feathers and mammals can regrow skin, lizards can regenerate entire structures such as their tails. Despite these differences, all have evolved from the same ancestor as lizards. Spreading through the Americas, one lizard group, the anoles, evolved like Darwin's finches, adapting to different islands and different habitats on the mainland. Today there are more than 400 species. Constructing a family tree for three lizard species collected in Panama at the Smithsonian Tropical Research Institute (STRI) and a fourth from the southeastern U.S., scientists at Arizona State University (ASU) compared lizard genomes--their entire DNA code--to those of other animals. The researchers discovered that changes in genes involved in the interbrain (the site of the pineal gland and other endocrine glands), for color vision, hormones, and the colorful dewlap that males bob to attract females, may contribute to the formation of boundaries between species. Genes regulating limb development also evolved especially quickly. "While some reptiles, such as tortoises, changed remarkably little over millions of years, anole lizards evolved quickly, generating a diversity of shapes and behaviors," said Dr. Kenro Kusumi, corresponding author and Professor at the ASU School of Life Sciences. "Now that sequencing entire genomes is cheaper and easier, we discovered molecular genetic evidence for rapid evolution that may account for striking differences between bodies of animals living in different environments." The study's findings were published in the February 1, 2018 issue of Genome Biology and Evolution. The open-access article is titled "Comparative Genomics Reveals Accelerated Evolution in Conserved Pathways during the Diversification of Anole Lizards." Dr.