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Scientists Discover New Causes of Cellular Decline in Prematurely Aging Children (Progeria); Finding May Shed Light on Normal Aging

In a paper published in the February 20, 2018 issue of Cell Reports, Saint Louis University researchers have uncovered new answers about why cells age in children with a rare and fatal disease, Hutchinson-Gilford Progeria Syndrome (HGPS). The open-access article is titled “A Cell-Intrinsic Interferon-like Response Links Replication Stress to Cellular Aging Caused by Progerin.” The data points to cellular replication stress and a mistaken innate immune response as culprits, and the team found success in the laboratory in blocking these processes with vitamin D. Susana Gonzalo, PhD, Associate Professor of Biochemistry and Molecular Biology at SLU, and her lab examined human and animal cells connected to HGPS. HGPS is caused by the random mutation of a single gene that causes children to age rapidly. Children with the condition develop many of the typical changes and illness associated with aging, including hair loss, aging skin, joint abnormalities, and bone loss. The disease causes atherosclerosis -- fatty deposits that clog arteries -- and patients with the illness die from cardiovascular complications such as stroke or myocardial infarction in their teens. Thanks to genetic mapping, scientists now know that HGPS is caused by a mutation in the LMNA gene, which encodes the lamin A protein. Lamin A serves as a scaffold that keeps the cell's nucleus organized and in shape. The shortened, mutated version of this protein is called progerin, and it causes the nucleus and cell to become unstable, leading to premature aging of the cells. "Those with progeria have a mutation in their DNA that codes for these proteins," Dr. Gonzalo said. "The presence of progerin makes a mess in the nucleus." This is a problem because the nucleus houses our DNA.

Termite Queen, King Recognition Pheromone Identified

Researchers at North Carolina (NC) State University have, for the first time, identified a specific chemical used by the higher termite castes -- the queens and the kings -- to communicate their royal status with worker termites. The findings could advance knowledge of termite evolution, behavior, and control. A study published online on March 19, 2018 in PNAS shows that a wax-like hydrocarbon -- a chemical consisting of only carbon and hydrogen atoms called heneicosane -- on the body surface of subterranean royal termites is used to enable worker termites to recognize and care for them. The open-access article is titled “"Identification of a Queen and King Recognition Pheromone in the Subterranean Termite Reticulitermes flavipes.” Termites live mostly underground or in wood and are generally blind, necessitating the use of chemical signals to communicate. "This is the first report of a queen recognition pheromone in termites and the first report of a king recognition pheromone in insects," said Coby Schal, PhD, the Blanton J. Whitmire Distinguished Professor of Entomology at NC State. Dr. Schal and NC State Ph.D. graduate Colin Funaro, the paper's co-corresponding authors, used gas chromatography to isolate specific chemicals from the exoskeletons of royal and worker Reticulitermes flavipes termites and found heneicosane on the royal termites, but not on workers. When heneicosane was placed on glass dummies serving as royal termite proxies, workers did not bow or curtsy, but instead started shaking -- an action that seemed to reflect the termite version of royal recognition. Workers shook even more when the royal pheromone was blended with other hydrocarbons from the colony's workers that represent the colony's odor.

New Long-Noncoding RNA (lncRNA) Biomarkers Identified for Neuroblastoma, a Type of Cancer in Children

Two new biomarkers for a type of cancer in children called neuroblastoma have been identified in a study published in the March 12, 2018 issue of Cancer Cell. The article is titled “Sense-Antisense lncRNA Pair Encoded by Locus 6p22.3 Determines Neuroblastoma Susceptibility via the USP36-CHD7-SOX9 Regulatory Axis.” The findings are expected to have immediate significance for disease prognosis, and eventually also for treatment. “There is a need for new methods of treatment for high-risk patients, and that’s where our research can lead to truly great benefits,” says Chandrasekhar Kanduri (photo), PhD, Professor of Medical Biochemistry and Cell Biology at Sahlgrenska Academy at Gothenburg University in Sweden. Neuroblastoma is the most common form of childhood cancer of the peripheral nervous system, the part of the nervous system that is not the brain or spinal cord. The disease can occur in the chest, neck, abdomen and adrenal glands and also spread to the spinal column. Symptoms may be general aches, anemia, and skeletal pains. When the disease is detected, the children are 17 months old on average and rarely over five years old. Milder variants of neuroblastoma may heal on their own in some cases, while the aggressive cases are the deadliest form of childhood cancer. Treatment is successful in less than half of these cases. Identification of high-risk patients is crucial, and this is where the new findings come in. With the support of patient data from Sweden (59 cases) and Germany (498 cases), researchers have identified two new types of RNA molecules that control the stability of tumor proteins and that, along with an already known RNA molecule, form a trio that can indicate how serious the condition of an individual patient is.

Autism's Social Deficits Are Reversed by Epigenetic Anti-Cancer Drug In Animal Models

Of all the challenges that come with a diagnosis of autism spectrum disorder (ASD), the social difficulties are among the most devastating. Currently, there is no treatment for this primary symptom of ASD. New research at the University at Buffalo (UB) in New York reveals the first evidence that it may be possible to use a single compound to alleviate the behavioral symptoms by targeting sets of genes involved in the disease. The research, published online on March 12, 2018 in Nature Neuroscience, demonstrated that brief treatment with a very low dose of romidepsin, an FDA-approved anti-cancer drug, restored social deficits in animal models of autism in a sustained fashion. The three-day treatment reversed social deficits in mice deficient in a gene called Shank 3, an important risk factor for ASD. This effect lasted for three weeks, spanning the juvenile to late adolescent period, a critical developmental stage for social and communication skills. That is equivalent to several years in humans, suggesting the effects of a similar treatment could potentially be long-lasting, the researchers say. The Nature Neuroscience article is titled “Social Deficits in Shank3-Deficient Mouse Models of Autism Are Rescued by Histone Deacetylase (HDAC) Inhibition.” "We have discovered a small molecule compound that shows a profound and prolonged effect on autism-like social deficits without obvious side effects, while many currently used compounds for treating a variety of psychiatric diseases have failed to exhibit the therapeutic efficacy for this core symptom of autism," said Zhen Yan (photo), PhD, Professor in the Department of Physiology and Biophysics in the Jacobs School of Medicine and Biomedical Sciences at UB, and senior author on the paper.

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").

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.

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.

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.

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.

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