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Archive - Nov 2013

November 11th

Nobel Prize Winner Says MicroRNAs and piRNAs Influence the Coordinated Regulation of Transcription in the Nucleus, and Translation at the Synapse—Neuroscience 2013

Classic behavioral studies of memory storage in people and animals have defined two temporally distinct phases for memory storage: a short-term memory lasting minutes that can be elicited by one training trial, and a long-term memory lasting days or more that typically requires repeated training trials. In earlier work, Eric Kandel, M.D., Director of the Kavil Institute for Brain Science at Columbia University, Howard Hughes Medical Institute senior investigator, and a co-recipient of the 2000 Nobel Prize in Physiology or Medicine for discoveries concerning signal transduction in the nervous system, together with colleagues, delineated these two behavioral memory phases in studies of learned fear, an implicit form of memory, using the simple gill-withdrawal reflex of Aplysia, which is a marine snail. This work revealed that there is a cellular representation of the learning process. The substrate of learning is the synapse, and learning leads to changes in the strength of synaptic connections. These studies found that short-term memory is mediated by a transient synaptic facilitation of pre-existing connections due to covalent modification of pre-existing proteins, whereas long-term memory results from a persistent facilitation mediated by transcription and synaptic growth. The critical transcriptional switch that converts short-term to long-term facilitation and long-term memory in Aplysia is mediated by the removal of the repressive step of CREB-2 and the activation of CREB-1. Because small RNAs are important in transcriptional control and post-transcriptional regulation of gene expression, Dr. Kandel and his group wondered whether they might also regulate this key transcriptional switch from short-term to long-term memory. Together with collaborators, Dr.

Experiences, Including Learning and Drug Use, Leave Genetic Marks on Brain Behavior—Neuroscience 2013

New human and animal research released today demonstrates how experiences impact genes that influence behavior and health. Today’s studies, presented at a press conference of Neuroscience 2013, the annual meeting of the Society for Neuroscience and the world’s largest source of emerging news about brain science and health, provide new insights into how experience might produce long-term brain changes in behaviors like drug addiction and memory formation. 30,000 scientists are attending this meeting in San Diego. Years of heroin abuse may change how genes are expressed and how the brain functions, according to new human research described today in a news conference organized by the Society of Neuroscience. The studies focus on an area of research called epigenetics, in which the environment and experiences can turn genes “on” or “off,” while keeping underlying DNA intact. These changes affect normal brain processes, such as development or memory, and abnormal brain processes, such as depression, drug dependence, and other psychiatric disease — and can be passed down to subsequent generations. According to the World Health Organization, 9.5 million people abuse heroin around the world, which increases their risk of death by 20 to 30 times compared to that of non-drug users. “Our study addresses a critical gap in our knowledge about heroin addiction because we cannot often directly study the brains of addicted humans,” said senior author Yasmin Hurd, Ph.D., of the Icahn School of Medicine at Mount Sinai in New York. “Our results provide important insights into how human brains change in response to long-term heroin use, and give us to knowledge to help treat this dangerous disease.” Dr.

Absence of Specific Serotonin Receptor During Development Linked to Aggression and Impulsivity in Adults—Neuroscience 2013

Blocking serotonin receptors during development results in highly aggressive and impulsive behavior, according to new animal research. Reintroducing the receptors in adulthood suppresses impulsivity, but not aggression, to normal levels. These and related findings were described during a press conference on Sunday, November 10, at Neuroscience 2013, the annual meeting of the Society for Neuroscience and the world’s largest source of emerging news about brain science and health. 30,000 scientists are attending this convention in San Diego. Previous studies have identified a link between low serotonin levels and impulsive, violent aggression. However, therapeutic treatments that used antidepressants to increase serotonin generally did not reduce the negative behaviors. New research, led by Katherine Nautiyal, Ph.D., from Columbia University, identified a specific serotonin receptor (5-HT1B)(see image) as a key factor in aggressive and impulsive behaviors. Mice lacking this receptor during development exhibited more frequent and intense fighting than did control mice. They were also more impulsive in neutral situations, more vulnerable to abusing drugs, and demonstrated less restraint, even when rewarded to do so. Understanding the impact of changes in specific prefrontal regions during brain development could lead to new treatments and earlier interventions for disorders in which impulsivity plays a key factor. The research may have implications for understanding and dealing with aggressive and troublesome behaviors. The new findings show that: the absence of serotonin receptors during early development leads to highly aggressive and impulsive behaviors in mice.

November 10th

Blood-Clotting Protein May Offer Early Detection of Multiple Sclerosis—Neuroscience 2013

A protein involved in blood clotting may be a new indicator to help detect multiple sclerosis (MS) lesions before symptoms arise. The presence of the clotting protein, thrombin, signals an early stage of the disease when the blood-brain barrier is breached and the brain’s immune response is set into motion. The research was presented at Neuroscience 2013, the annual meeting of the Society for Neuroscience and the world’s largest source of emerging news about brain science and health. 30,000 scientists are attending this meeting. “Our research shows this indicator is a promising approach for detecting MS-like lesions early, even before major symptoms appear,” said senior author Katerina Akassoglou, Ph.D., of the Gladstone Institutes and the University of California, San Francisco. “Such sensitive indicators could act as red flags that signal neuroinflammatory changes in the brain not only in MS, but also in other diseases such as Alzheimer’s.” MS is a debilitating disorder that can be intermittent or progressive, and causes numbness, fatigue, difficulty walking, paralysis, and loss of vision in 2 million people worldwide. MS arises when the body’s immune system attacks its own myelin sheaths, the protective coverings that surround neurons and allow signals to move from one cell to the next. The researchers found that thrombin, usually a beneficial protein involved in blood clotting, builds up in the central nervous system as MS progresses. Thrombin enters in the brain together with fibrinogen, another clotting protein when the protective barrier between the blood and brain becomes leaky. Thrombin converts the fibrinogen to fibrin which activates brain’s immune cells that break down the protective myelin sheath that surrounds neurons in the central nervous system.

Dendritic-Cell-Derived Exosomes As Possible Therapy for Multiple Sclerosis--Neuroscience 2013

Currently, no multiple sclerosis (MS) treatments promote remyelination. Richard Kraig, M.D., Ph.D., Professor in Neurosciences and Director of the Migraine Headache Clinic at the University of Chicago Medicine, described to the press on Sunday, May 10, at the Society for Neuroscience 2013 meeting in San Diego, his group’s new work showing that dendritic cells, a type of immune cell present in blood, can be cultured from bone marrow and stimulated to release small particles called exosomes (see image). When administered to the brain, these exosomes significantly increase myelination and improve remyelination following a demyelinating injury, like that caused by MS. MS is an inflammatory disease involving oligodendrocyte loss, demyelination, and failure to remyelinate damaged brain areas. Oligodendrocytes in the central nervous system produce myelin, the insulation surrounding axons, which is necessary for neuronal signaling. Damage to oligodendrocytes and demyelination — loss of this insulation — can lead to severe neurological disability. Remyelination is a spontaneously occurring repair process mediated by recruitment of oligodendrocyte precursor cells to damaged areas. Their subsequent differentiation into mature oligodendrocytes is capable of replacing lost myelin. Initially, MS patients follow a relapsing-remitting disease course, characterized by periods of partial recovery associated with incomplete remyelination. However, over time this ability to repair declines and patients develop a secondary-progressive, steadily worsening disease course. With over 400,000 people currently suffering from MS in the United States, it is a significant and devastating healthcare burden.

Scientists Unveil New Understanding, Warning Signs, and Potential Treatments for Multiple Sclerosis--Neurocience 2013

Scientists are gaining a new level of understanding of multiple sclerosis (MS) that may lead to new treatments and approaches to controlling the chronic disease, according to new research released in San Diego on Sunday, November 10, at Neuroscience 2013, the annual meeting of the Society for Neuroscience and the world’s largest source of emerging news about brain science and health. Approximately 30,000 scientists are attending this year’s meeting. MS is a severe, often crippling, autoimmune disease caused by the body’s immune system attacking the nervous system. Today, more than two million people worldwide suffer from MS and other neuroinflammatory diseases. MS usually strikes in early adulthood and manifests with symptoms including vision loss, paralysis, numbness, and fatigue. The disease can be intermittent or progressive and currently has no cure. Today’s new findings show that: scientists are one step closer to understanding how antibodies in the blood stream break past the brain’s protective barrier to attack the optic nerves, spinal cord, and brain, causing the symptoms of neuromyelitis optica, a rare disease similar to MS. Understanding how the antibodies bypass the protective blood-brain barrier could provide new approaches to treating the disease (Yukio Takeshita, M.D., Ph.D., abstract 404.09); a protein involved in blood clotting might serve as an early detection method for MS before symptoms occur. Early detection of the disease could lead to more effective early treatments (Katerina Akassoglou, Ph.D., abstract 404.11); low levels of a cholesterol protein correlate with the severity of a patient’s MS in both human patients and mouse models. The finding suggests the protein, known to protect against inflammation, may protect against developing MS, and possibly even aid in the regeneration of damaged neurons.

Research Reveals Positive Roles for Exercise, Diet, and Meditation in Aging and Depression—Neuroscience 2013

New studies released on Sunday, November 10, 2013, underscore the potential impact of healthy lifestyle choices in treating depression, the effects of aging, and learning. The research focused on the effects of mind/body awareness, exercise, and diet, and was presented in San Diego at Neuroscience 2013, the annual meeting of the Society for Neuroscience and the world’s largest source of emerging news about brain science and health. The 2013 meeting is being attended by approximately 30,000 scientists. The experiences and choices people make throughout life actively impact the brain. As humans live longer, these choices also affect aging and quality of life. Lifestyle changes to diet and exercise will be important to aging populations as non-drug, easy-to-follow interventions with few side effects, making ideal potential therapies. Today’s new findings show that: as few as 12 consecutive days of exercise in aging rats helps preserve and improve movement function, an effect possibly caused by changes in dopamine levels. The results suggest that exercise could stave off or reverse the slowed movements that are hallmarks of age (Jennifer Arnold, abstract 334.02); practices like yoga or meditation that increase mind/body awareness help people learn a brain-computer interface quicker. This finding may have implications for those who need brain-computer interfaces to function, such as people with paralysis (Bin He, Ph.D., abstract 16.06); long-term exercise in aging rats improves memory function, as well as increases the number of blood vessels in the white matter of their brains — the tracts that carry information between different areas of the brain.

Lumosity Presents New Data on Measuring Cognitive Training Improvements--Neuroscience 2013

Lumosity, the online cognitive training and neuroscience research company, is presenting today, at the annual 2013 Society for Neuroscience meeting, data on its set of online neuropsychological battery of assessments, the Brain Performance Test (BPT). The poster presentation titled, "Measuring Training-Related Changes in Cognitive Performance with a Repeatable Online Assessment Battery," examined the reliability of the BPT and the variability in training dose and improvement. The study found that the BPT is a reliable assessment, and that larger doses of cognitive training are associated with greater improvements on the BPT. The study also found that training gains were more strongly predictive of improvements on the assessment battery than the training dose alone.,"We created the Brain Performance Test with the goal of improving the way we measure the transfer effects of cognitive training to other tasks and real-world outcomes," said Daniel Sternberg, Ph.D., Data Scientist at Lumosity and lead author of the study. "These results are interesting because they demonstrate that training gains are a powerful predictor of transfer – replicating previous findings from other labs, but in a much larger sample." The study included a final sample of 5,870 participants between the ages of 15-75 who took the pre-test and post-test at least 70 days apart. The study found that those who trained more than the median participants — approximately 10.5 hours over a 10-week period — saw increases in improvements on core cognitive abilities compared to those who trained less. Current ongoing research using the BPT includes a randomized controlled study, multiple studies comparing the effects of different training programs on training improvements, and assessment validation studies.

November 9th

NIH Launches Clinical Trial of Investigational Genital Herpes Vaccine

Researchers have launched an early-stage clinical trial of an investigational vaccine designed to prevent genital herpes disease. The National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, is sponsoring the Phase I trial, which is being conducted at the NIH Clinical Center in Bethesda, Maryland. Genital herpes is one of the most common sexually transmitted infections in the United States. Most genital herpes cases are caused by infection with herpes simplex virus type 2 (HSV-2); however, herpes simplex virus type 1 (HSV-1) can also cause genital herpes. An estimated 776,000 people in the United States are infected with HSV-2 or HSV-1 each year. There is no vaccine to prevent genital herpes. "Although genital herpes is treatable, it is a lifelong infection that can exact a substantial psychological and physical toll on infected individuals and places them at higher risk of acquiring HIV," said NIAID Director Anthony S. Fauci, M.D. "Furthermore, mothers with active genital herpes infection at time of delivery can transmit the virus to their newborns, which can lead to severe illness and death. A protective vaccine would help to reduce significantly the spread of this all-too- common sexually transmitted infection," Dr. Fauci added. Led by principal investigator Lesia K. Dropulic, M.D., of NIAID's Laboratory of Infectious Diseases, the trial will test an investigational HSV-2 vaccine candidate, called HSV529, for safety and the ability to generate an immune system response. The investigational vaccine, manufactured by Sanofi Pasteur, was developed by David Knipe, Ph.D., professor of microbiology and immunobiology at Harvard Medical School, Boston. Preclinical testing of the candidate vaccine involved a 10-year collaborative effort between Dr.

Earliest-Ever Marker for Autism Found in Young Infants

Eye contact during early infancy may be a key to early identification of autism, according to a study funded by the National Institute of Mental Health (NIMH), part of the National Institutes of Health. Published online on November 6, 2013 in Nature, the study reveals the earliest sign of developing autism ever observed—a steady decline in attention to others' eyes within the first two to six months of life. "Autism isn't usually diagnosed until after age 2, when delays in a child's social behavior and language skills become apparent. This study shows that children exhibit clear signs of autism at a much younger age," said Thomas R. Insel, M.D., director of the NIMH. "The sooner we are able to identify early markers for autism, the more effective our treatment interventions can be." Typically developing children begin to focus on human faces within the first few hours of life, and they learn to pick up social cues by paying special attention to other people's eyes. Children with autism, however, do not exhibit this sort of interest in eye-looking. In fact, a lack of eye contact is one of the diagnostic features of the disorder. To find out how this deficit in eye-looking emerges in children with autism, Warren Jones, Ph.D., and Ami Klin, Ph.D., of the Marcus Autism Center, Children's Healthcare of Atlanta, and Emory University School of Medicine, followed infants from birth to age 3. The infants were divided into two groups, based on their risk for developing an autism spectrum disorder. Those in the high-risk group had an older sibling already diagnosed with autism; those in the low-risk group did not. Drs. Jones and Klin used eye-tracking equipment to measure each child's eye movements as they watched video scenes of a caregiver.