How chronic stress predisposes brain to mental disorders

University of California, Berkeley, researchers have shown that chronic stress generates long-term changes in the brain that may explain why people suffering chronic stress are prone to mental problems such as anxiety and mood disorders later in life.Their findings could lead to new therapies to reduce the risk of developing mental illness after stressful events.Doctors know that people with stress-related illnesses, such as post-traumatic stress disorder (PTSD), have abnormalities in the brain, including differences in the amount of gray matter versus white matter. Gray matter consists mostly of cells — neurons, which store and process information, and support cells called glia — while white matter is composed of axons, which create a network of fibers that interconnect neurons. White matter gets its name from the white, fatty myelin sheath that surrounds the axons and speeds the flow of electrical signals from cell to cell.How chronic stress creates these long-lasting changes in brain structure is a mystery that researchers are only now beginning to unravel.In a series of experiments, Daniela Kaufer, UC Berkeley associate professor of integrative biology, and her colleagues, including graduate students Sundari Chetty and Aaron Freidman, discovered that chronic stress generates more myelin-producing cells and fewer neurons than normal. This results in an excess of myelin — and thus, white matter — in some areas of the brain, which disrupts the delicate balance and timing of communication within the brain.”We studied only one part of the brain, the hippocampus, but our findings could provide insight into how white matter is changing in conditions such as schizophrenia, autism, depression, suicide, ADHD and PTSD,” she said.The hippocampus regulates memory and emotions, and plays a role in various emotional disorders.Kaufer and her colleagues published their findings in the Feb. 11 issue of the journal Molecular Psychiatry.Does stress affect brain connectivity?Kaufer’s findings suggest a mechanism that may explain some changes in brain connectivity in people with PTSD, for example. One can imagine, she said, that PTSD patients could develop a stronger connectivity between the hippocampus and the amygdala — the seat of the brain’s fight or flight response — and lower than normal connectivity between the hippocampus and prefrontal cortex, which moderates our responses.”You can imagine that if your amygdala and hippocampus are better connected, that could mean that your fear responses are much quicker, which is something you see in stress survivors,” she said. “On the other hand, if your connections are not so good to the prefrontal cortex, your ability to shut down responses is impaired. So, when you are in a stressful situation, the inhibitory pathways from the prefrontal cortex telling you not to get stressed don’t work as well as the amygdala shouting to the hippocampus, ‘This is terrible!’ You have a much bigger response than you should.”She is involved in a study to test this hypothesis in PTSD patients, and continues to study brain changes in rodents subjected to chronic stress or to adverse environments in early life.Stress tweaks stem cellsKaufer’s lab, which conducts research on the molecular and cellular effects of acute and chronic stress, focused in this study on neural stem cells in the hippocampus of the brains of adult rats. These stem cells were previously thought to mature only into neurons or a type of glial cell called an astrocyte. The researchers found, however, that chronic stress also made stem cells in the hippocampus mature into another type of glial cell called an oligodendrocyte, which produces the myelin that sheaths nerve cells.The finding, which they demonstrated in rats and cultured rat brain cells, suggests a key role for oligodendrocytes in long-term and perhaps permanent changes in the brain that could set the stage for later mental problems. …

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Personal experience, work seniority improve mental health professionals’ outlook

One might think that after years of seeing people at their worst, mental health workers would harbor negative attitudes about mental illness, perhaps associating people with mental health issues as less competent or dangerous. But a new study suggests the opposite.In a survey of 731 mental health professionals in Washington state, the more seniority employees had on the job, the more positively they viewed people with mental illness. The survey also linked mental health workers’ positive attitudes with having advanced degrees and reporting a mental illness themselves.”The results suggest that the more exposure you have personally and professionally to mental illness, the more positive attitudes you’ll have,” said Jennifer Stuber, lead author of the paper and an assistant professor of social work at the University of Washington.Pervasive, stigmatizing views of people with mental illness can create barriers for their employment, housing, medical treatment and social relationships, wrote Stuber in the study published online in January by Psychiatric Services.Mental health workers having these biased, denigrating views could set low expectations for improvement for individuals seeking treatment, she said.The study, funded by the Substance Abuse and Mental Health Services Administration and National Institute of Mental Health, is among the first in the United States to examine attitudes among mental health professionals.”On one hand, it may be the case that mental health professionals become hardened, because they see people at their worst and become discouraged if treatment is slow,” Stuber said. “On the other hand, more experience may make mental health professionals more empathetic to their clients and aware of the possibility of recovery.”Stuber and her research team conducted 30-minute online surveys assessing the perceived competence and dangerousness of individuals with depression and schizophrenia. A sample of mental health professionals — counselors, social workers, psychologists, case managers and others — living in Washington read vignettes portraying people who had symptoms of depression or schizophrenia.Then the participants answered questions gauging how much distance they would want to keep from the people in the vignettes. Would they want the person as their neighbor, housemate, co-worker or spouse? How likely is the person to be dangerous or make responsible financial or treatment decisions? Such questions are used in other surveys that measure stereotypes and stigmas such as those against people who are gay or use drugs.Stuber and her colleagues found that mental health workers who had at least a four-year college degree, a job position denoting greater seniority (for example, program manager) and a mental illness themselves had more positive attitudes about people with mental health problems.”The finding that stands out the most is that almost a third of mental health professionals disclosed that they received a diagnosis of mental illness in the past,” Stuber said. “This prior experience was associated with less negative attitudes, which has implications for how we think of the relevance of that experience in recruiting for a mental health workforce.”The researchers compared the findings to attitudes held by non-experts, composed of close to 400 adults taking the biennial national General Social Survey.Overall, mental health workers held more positive attitudes than did the general public. For instance, 40 percent of mental health providers and 70 percent of the general public indicated they wouldn’t want someone with schizophrenia as a co-worker. …

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Caring for animals may correlate with positive traits in young adults

Young adults who care for an animal may have stronger social relationships and connection to their communities, according to a paper published online today in Applied Developmental Science.While there is mounting evidence of the effects of animals on children in therapeutic settings, not much is known about if and how everyday interactions with animals can impact positive youth development more broadly.”Our findings suggest that it may not be whether an animal is present in an individual’s life that is most significant but rather the quality of that relationship,” said the paper’s author, Megan Mueller, Ph.D., a developmental psychologist and research assistant professor at the Cummings School of Veterinary Medicine at Tufts University. “The young adults in the study who had strong attachment to pets reported feeling more connected to their communities and relationships.”Mueller surveyed more than 500 participants aged 18-26 and predominately female about their attitudes and interaction with animals. Those responses were indexed against responses the same participants had given on a range of questions that measure positive youth development characteristics such as competence, caring, confidence, connection, and character, as well as feelings of depression, as part of a national longitudinal study, the 4-H Study of Positive Youth Development, which was led by Tufts Professor of Child Development Richard Lerner, Ph.D., and funded by the National 4-H Council.Young adults who cared for animals reported engaging in more “contribution” activities, such as providing service to their community, helping friends or family and demonstrating leadership, than those who did not. The more actively they participated in the pet’s care, the higher the contribution scores. The study also found that high levels of attachment to an animal in late adolescence and young adulthood were positively associated with feeling connected with other people, having empathy and feeling confident.”We can’t draw causal links with this study but it is a promising starting point to better understanding the role of animals in our lives, especially when we are young,” said Mueller.To learn more about how and if interacting with animals is linked with positive youth development future studies need to look at specific features of human experiences with animal experiences, as well as how these relationships develop over time, and include a larger, more diverse sample, Mueller noted.Mueller has a unique vantage point from which to study human-animal interaction. As both a developmental psychologist and a faculty member at the Cummings School, she has insight into both sides of the relationship between people and animals, and is a leader in bringing the developmental perspective to the field.Story Source:The above story is based on materials provided by Tufts University. Note: Materials may be edited for content and length.

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New links found between sleep duration, depression

A genetic study of adult twins and a community-based study of adolescents both report novel links between sleep duration and depression. The studies are published in the Feb. 1 issue of the journal Sleep.”Healthy sleep is a necessity for physical, mental and emotional well-being,” said American Academy of Sleep Medicine President Dr. M. Safwan Badr. “This new research emphasizes that we can make an investment in our health by prioritizing sleep.”A study of 1,788 adult twins is the first to demonstrate a gene by environment interaction between self-reported habitual sleep duration and depressive symptoms. Results suggest that sleep durations outside the normal range increase the genetic risk for depressive symptoms. Among twins with a normal sleep duration of seven to 8.9 hours per night, the total heritability of depressive symptoms was 27 percent. However, the genetic influence on depressive symptoms increased to 53 percent among twins with a short sleep duration of five hours per night and 49 percent among those who reported sleeping 10 hours per night.”We were surprised that the heritability of depressive symptoms in twins with very short sleep was nearly twice the heritability in twins sleeping normal amounts of time,” said principal investigator Dr. Nathaniel Watson, associate professor of neurology and co-director of the University of Washington Medicine Sleep Center in Seattle, Wash. …

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Does caregiving cause psychological stress? It depends, says study of female twins

When it comes to life’s stressors, most people would put caregiving at the top of the list. But according to Peter Vitaliano, a professor of psychiatry and psychology at the University of Washington (UW), there never have been data actually showing caregiving causes psychological distress. So he, and other researchers at the UW conducted a study of about 1,228 female twins, some were caregivers, and some were not. The results were somewhat surprising.The study, “Does caregiving cause psychological distress? The case for familial and genetic vulnerabilities in female twins,” was published in the Annals of Behavioral Medicine in January 2014 and showed that the associations between caregiving and different types of psychological distress (depression, anxiety, perceived stress and perceived mental health) depend largely on a person’s genes and upbringing — and less so on the difficulty of caregiving.Did the person have a history of depression before being a caregiver? If so, “caregiving may be like putting salt on the wound,” said Vitaliano. If there’s no depression in the past, caregivers don’t seem more affected by depression than noncaregivers.Depression and perceived mental health are the most influenced by genes, said Vitaliano. Anxiety is most related to caregiving, and people who don’t get relief from anxiety are more likely to become depressed, he noted.Perceived stress, meanwhile, is almost exclusively related to the kind of environment a person was raised in, not genetics or caregiver status, he said. If a person grows up in a home where one’s parents show lots of avoidance and fear in response to a lost job or sickness , then he or she will likely model that behavior.Vitaliano said these results break the long-held belief that caregiving directly causes distress. He noted that since 1953 there have been more than a thousand papers on distress among caregivers without any data showing causality.By examining twin pairs — both monozygotic (identical from same fertilized egg) and dizygotic (fraternal from separate fertilized eggs) — UW researchers assessed the extent psychological distress is related to caregiving, or confounded by common genes and environmental exposure. …

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Boat Pose

Cardio Workouts Lose Weight Get Stronger Yoga & Pilates Recipes Must-Eat Foods Celebrity Chefs Myths & Facts Skin & Anti-Aging Hair & Makeup Slimming Style Celebrity Tips Adult ADHD Alzheimer’s Disease Asthma Bipolar Disorder Birth Control Breast Cancer Childhood Vaccines Cholesterol Chronic Pain Cold, Flu, and Sinus COPD Crohn’s Disease Depression Diabetes (Type 2) Fibromyalgia GERD Headaches & Migraines Incontinence Menopause Multiple Sclerosis Osteoarthritis Osteoporosis Psoriasis Rheumatoid Arthritis Sexual Health Sleep Disorders More Conditions Current Issue Subscribe Tablet Edition Archive Give a Gift Subscription Customer Service Media Kit Home>>Diet & Fitness>>Yoga & Pilates>> Boat PoseHow to FitnessBoat PoseThis great yoga move helps flatten out your belly.The 5 Best Vacation Spots for Hiking Light, Bright Sneakers for Summer Walk a Little…

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Reward with Music

Cardio Workouts Lose Weight Get Stronger Yoga & Pilates Recipes Must-Eat Foods Celebrity Chefs Myths & Facts Skin & Anti-Aging Hair & Makeup Slimming Style Celebrity Tips Adult ADHD Alzheimer’s Disease Asthma Bipolar Disorder Birth Control Breast Cancer Childhood Vaccines Cholesterol Chronic Pain Cold, Flu, and Sinus COPD Crohn’s Disease Depression Diabetes (Type 2) Fibromyalgia GERD Headaches & Migraines Incontinence Menopause Multiple Sclerosis Osteoarthritis Osteoporosis Psoriasis Rheumatoid Arthritis Sexual Health Sleep Disorders More Conditions Current Issue Subscribe Tablet Edition Archive Give a Gift Subscription Customer Service Media Kit Home>>Diet & Fitness>>Cardio Workouts>> Reward with MusicHealth TipsReward with MusicGet healthier now with our expert advice.How to Become an Exercise Addict 30-Minute Workout, No Gym Required 18 Moves to Tone Your Legs…

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Upward Dog

Cardio Workouts Lose Weight Get Stronger Yoga & Pilates Recipes Must-Eat Foods Celebrity Chefs Myths & Facts Skin & Anti-Aging Hair & Makeup Slimming Style Celebrity Tips Adult ADHD Alzheimer’s Disease Asthma Bipolar Disorder Birth Control Breast Cancer Childhood Vaccines Cholesterol Chronic Pain Cold, Flu, and Sinus COPD Crohn’s Disease Depression Diabetes (Type 2) Fibromyalgia GERD Headaches & Migraines Incontinence Menopause Multiple Sclerosis Osteoarthritis Osteoporosis Psoriasis Rheumatoid Arthritis Sexual Health Sleep Disorders More Conditions Current Issue Subscribe Tablet Edition Archive Give a Gift Subscription Customer Service Media Kit Home>>Diet & Fitness>>Yoga & Pilates>> Upward DogHow to FitnessUpward DogOne of the best upper body exercises you’ve ever tried, and you don’t have to be a yoga person to do it.12 Yoga…

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When a Loved One Suffers Abuse in a Nursing Home

The idea of a loved one being abused while living in a nursing home, assisted living center, or other elder care environment is a difficult thought to deal with. As more and more Americans reach retirement age every day and the average lifespan keeps increasing, the chances that you or a family member will have to live in a nursing home are high. But, many people don’t realize that nursing home and elder abuse is a growing, and unfortunately common, problem for many seniors.Abuse, Neglect, and MalpracticeAn elderly person who is injured in a nursing home or elder care facility can often sue that facility when its actions directly led to the harms the elderly person suffered. These types of cases are typically divided into one of three types: abuse, neglect, and malpractice.Abuse. When nursing home employees intentionally hurt a patient, that’s nursing home abuse. Abuse can result from a variety of circumstances, such as unreasonable confinement, physical or psychological intimidation, or the purposeful infliction of physical injuries. In some situations, nursing home workers even commit sexual abuse against the elderly resident. Nursing home abuse can result in either physical pain, or mental and psychological anguish. Neglect. Neglect is slightly different than abuse. …

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Sticks and stones: Brain releases natural painkillers during social rejection

Oct. 10, 2013 — “Sticks and stones may break my bones, but words will never hurt me,” goes the playground rhyme that’s supposed to help children endure taunts from classmates. But a new study suggests that there’s more going on inside our brains when someone snubs us — and that the brain may have its own way of easing social pain.The findings, recently published in Molecular Psychiatry by a University of Michigan Medical School team, show that the brain’s natural painkiller system responds to social rejection — not just physical injury.What’s more, people who score high on a personality trait called resilience — the ability to adjust to environmental change — had the highest amount of natural painkiller activation.The team, based at U-M’s Molecular and Behavioral Neuroscience Institute, used an innovative approach to make its findings. They combined advanced brain scanning that can track chemical release in the brain with a model of social rejection based on online dating. The work was funded by the U-M Depression Center, the Michigan Institute for Clinical and Health Research, the Brain & Behavior Research Foundation, the Phil F Jenkins Foundation, and the National Institutes of Health.They focused on the mu-opioid receptor system in the brain — the same system that the team has studied for years in relation to response to physical pain. Over more than a decade, U-M work has shown that when a person feels physical pain, their brains release chemicals called opioids into the space between neurons, dampening pain signals.David T. Hsu, Ph.D., the lead author of the new paper, says the new research on social rejection grew out of recent studies by others, which suggests that the brain pathways that are activated during physical pain and social pain are similar.”This is the first study to peer into the human brain to show that the opioid system is activated during social rejection,” says Hsu, a research assistant professor of psychiatry. “In general, opioids have been known to be released during social distress and isolation in animals, but where this occurs in the human brain has not been shown until now.”The study involved 18 adults who were asked to view photos and fictitious personal profiles of hundreds of other adults. Each selected some who they might be most interested in romantically — a setup similar to online dating.But then, when the participants were lying in a brain imaging machine called a PET scanner, they were informed that the individuals they found attractive and interesting were not interested in them.Brain scans made during these moments showed opioid release, measured by looking at the availability of mu-opioid receptors on brain cells. The effect was largest in the brain regions called the ventral striatum, amygdala, midline thalamus, and periaqueductal gray — areas that are also known to be involved in physical pain.The researchers had actually made sure the participants understood ahead of time that the “dating” profiles were not real, and neither was the “rejection.” But nonetheless, the simulated social rejection was enough to cause both an emotional and opioid response.Suffering slings and arrows differentlyHsu notes that the underlying personality of the participants appeared to play a role in how much of a response their opioid systems made.”Individuals who scored high for the resiliency trait on a personality questionnaire tended to be capable of more opioid release during social rejection, especially in the amygdala,” a region of the brain involved in emotional processing, Hsu says. …

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Exercise provides some benefits for depression

Sep. 11, 2013 — Exercise may benefit people suffering from depression, according to an updated systematic review published in The Cochrane Library. The authors of the review found evidence to suggest that exercise reduces symptoms of depression, although they say more high quality trials are needed.Worldwide, more than 120 million people suffer from depression. Antidepressants and psychological therapies are recommended as effective treatments for depression. However, antidepressants have side-effects and some people prefer not to receive, or may not have access to, psychological therapies. Physical exercise is also used as a treatment for depression. There are a number of reasons why it might work such as changing hormone levels that affect mood or providing a distraction from negative thoughts.The previous version of the Cochrane review found only limited evidence of benefit for exercise in depression. However, more trials have now been completed, leading researchers to carry out a further update. Altogether, they reviewed the results of 39 trials involving 2,326 people diagnosed with depression. The severity of patients’ symptoms was assessed using standard scales of depression.In 35 trials comparing exercise with control treatments or no treatment, the researchers saw moderate benefits of exercise for treating depression. …

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Red cedar tree study shows that clean air act is reducing pollution, improving forests

Sep. 2, 2013 — A collaborative project involving a Kansas State University ecologist has shown that the Clean Air Act has helped forest systems recover from decades of sulfur pollution and acid rain.The research team — which included Jesse Nippert, associate professor of biology — spent four years studying centuries-old eastern red cedar trees, or Juniperus virginiana, in the Central Appalachian Mountains of West Virginia. The region is downwind of the Ohio River Valley coal power plants and experienced high amounts of acidic pollution — caused by sulfur dioxide emissions — in the 20th century.By studying more than 100 years of eastern red cedar tree rings, the scientists found that the trees have improved in growth and physiology in the decades since the Clean Air Act was passed in 1970.”There is a clear shift in the growth, reflecting the impact of key environmental legislation,” Nippert said. “There are two levels of significance in this research. One is in terms of how we interpret data from tree rings and how we interpret the physiology of trees. The other level of significance is that environmental legislation can have a tremendous impact on an entire ecosystem.”The findings appear in the scientific journal Proceedings of the National Academy of Sciences, or PNAS, in the article “Evidence of recovery of Juniperus virginiana trees from sulfur pollution after the Clean Air Act.”The principal investigator on the project was Richard Thomas, professor of biology at West Virginia University. Other researchers include Scott Spal, master’s graduate from West Virginia University, and Kenneth Smith, undergraduate student at West Virginia University.For the study, the scientists collected and analyzed data from eastern red cedar trees ranging from 100 to 500 years old. The researchers wanted to better understand the trees’ physiological response and the growth response to long-term acid deposition, or acid rain.The team focused on red cedar trees because they are abundant, long-lived and a good recorder of environmental variability. Red cedar trees grow slowly and rely on surface soil moisture, which makes them sensitive to environmental change. Their abilities to live for centuries meant that researchers could analyze hundreds of years of tree rings, Nippert said.The researchers analyzed the stable carbon isotopes within each tree ring as a recorder of physiological changes through time. …

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Maternal posttraumatic stress disorder associated with increased risk for child maltreatment

Sep. 2, 2013 — Posttraumatic stress disorder (PTSD) in mothers appears to be associated with an increased risk for child maltreatment beyond that associated with maternal depression, according to a study published by JAMA Pediatrics, a JAMA Network publication.The psychopathology of a caregiver is understood to be an important risk factor for child maltreatment and maternal depression is associated with an increased use of corporal punishment and physical abuse of children. Until recently, research on maternal depression and maltreatment risk has largely ignored the high rate of comorbidity between depression and PTSD. The National Comorbidity Survey suggests that 24.7 percent of depressed women have PTSD and that 48.4 of women with PTSD have depression, according to the study background.Claude M. Chemtob, Ph.D., of the NYU School of Medicine, and colleagues examined the association of probable maternal depression, PTSD and comorbid PTSD and depression with the risk for child maltreatment and parenting stress and with the number of traumatic events that preschool children are exposed to.The study included 97 mothers of children ages 3 to 5 years old. About half of the children were boys.The children of mothers with PTSD (mean number of events the child was exposed to, 5) or with comorbid PTSD and depression (3.5 events) experienced more traumatic events than those of mothers with depression (1.2 events) or neither disorder (1.4 events). When PTSD symptom severity scores were high, psychological aggression and the number of traumatic events children experienced increased. Depressive symptom severity scores also were associated with the risk for psychological aggression and exposure to traumatic events only when PTSD symptom severity scores were low, according to the study results.”Mothers in the comorbid group reported the highest levels of physically and psychologically abusive behaviors and overall parenting stress. Although not statistically significant, mothers with depression alone showed a trend toward endorsing more physically abusive and neglectful parenting behaviors,” the study concludes. “Given the high comorbidity between PTSD and depression, these findings suggest the importance of measuring PTSD symptoms when considering the relationship between depression and increased risk for child maltreatment.”

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Average height of European males has grown by 11 centimeters in just over a century

Sep. 2, 2013 — The average height of European males increased by an unprecedented 11 cm between the mid-nineteenth century and 1980, according to a new paper published online today in the journal Oxford Economic Papers. Contrary to expectations, the study also reveals that average height actually accelerated in the period spanning the two World Wars and the Great Depression.Timothy J. Hatton, Professor of Economics at the University of Essex and the Research School of Economics at Australian National University in Canberra, examined and analysed a new dataset for the average height (at the age of around 21) of adult male birth cohorts, from the 1870s to 1980, in fifteen European countries. The data were drawn from a variety of sources. For the most recent decades the data were mainly taken from height-by-age in cross sectional surveys. Meanwhile, observations for the earlier years were based on data for the heights of military conscripts and recruits. The data is for men only as the historical evidence for women’s heights is severely limited.Professor Hatton said, “Increases in human stature are a key indicator of improvements in the average health of populations. The evidence suggests that the improving disease environment, as reflected in the fall in infant mortality, is the single most important factor driving the increase in height. The link between infant mortality and height has already been demonstrated by a number of studies.” Infant mortality rates fell from an average of 178 per thousand in 1871-5 to 120 per thousand in 1911-15. …

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Meeting report: �Depression and Anxiety Spectrum disorders

Dr. Eskandar gave an overview of neurosurgical and physiological studies in both animal and human studies; Dr. Akil gave an overview of the underlying biology associated with stress and depression; and Dr. Dougherty discussed using …

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Shutting off neurons helps bullied mice overcome symptoms of depression

Aug. 29, 2013 — A new drug target to treat depression and other mood disorders may lie in a group of GABA neurons (gamma-aminobutyric acid -the neurotransmitters which inhibit other cells) shown to contribute to symptoms like social withdrawal and increased anxiety, Penn Medicine researchers report in a new study in the Journal of Neuroscience.Experts know that people suffering from depression and other mood disorders often react to rejection or bullying by withdrawing themselves socially more than the average person who takes it in strides, yet the biological processes behind these responses have remained unclear.Now, a preclinical study, from the lab of Olivier Berton, PhD, an assistant professor in the department of Psychiatry, in collaboration with Sheryl Beck, PhD, a professor in the department of Anesthesiology at Children’s Hospital of Philadelphia, found that bullying and other social stresses triggered symptoms of depression in mice by activating GABA neurons, in a never-before-seen direct relationship between social stimuli and this neural circuitry. Activation of those neurons, they found, directly inhibited levels of serotonin, long known to play a vital role in behavioral responses — without it, a depressed person is more likely to socially withdrawal.Conversely, when the researchers successfully put the brake on the GABA neurons, mice became more resilient to bullying and didn’t avoid once -perceived threats.”This is the first time that GABA neuron activity — found deep in the brainstem — has been shown to play a key role in the cognitive processes associated with social approach or avoidance behavior in mammals,” said Dr. Berton. “The results help us to understand why current antidepressants may not work for everyone and how to make them work better — by targeting GABA neurons that put the brake on serotonin cells.”Less serotonin elicits socially defensive responses such as avoidance or submission, where enhancement — the main goal of antidepressants — induces a positive shift in the perception of socio-affective stimuli, promoting affiliation and dominance. However, current antidepressants targeting serotonin, like SSRIs, are only effective in about 50 percent of patients.These new findings point to GABA neurons as a new, neural drug target that could help treat the other patients who don’t respond to today’s treatment.For the study, “avoidant” mice were exposed to brief bouts of aggression from trained “bully” mice. By comparing gene expression in the brains of resilient and avoidant mice, Berton and colleagues discovered that bullying in avoidant mice puts GABA neurons in a state where they become more excitable and the mice exhibit signs of social defeat. Resilient mice, however, had no change in neuron levels and behavior.To better understand the link between GABA and the development of stress resilience, Berton, Beck, and colleagues also devised an optogenetics-based approach to directly manipulate levels: Lifting GABA inhibition of serotonin neurons reduced social and anxiety symptoms in mice exposed to bullies and also fully prevented neurobiological changes due to stress.”Our paper provides a novel cellular understanding of how social defensiveness and social withdrawal develop in mice and gives us a stepping stone to better understand the basis of similar social symptoms in humans,” said Berton. “This has important implications for the understanding and treatment of mood disorders.”This work was funded by the National Institute of Mental Health grants MH087581, MH0754047 and MH089800 and grants from the International Mental Health Research Organization, the National Alliance for Research on Schizophrenia and Depression and the National Institute on Drug Abuse.Co-authors on the study include Collin Challis, Janette Boulden, Avin Veerakumar, Julie Espallergues, and R. Christopher Pierce from Penn’s department of Psychiatry.

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Brain inflammation linked to more severe Parkinson’s symptoms

Aug. 28, 2013 — Reversing inflammation in the fluid surrounding the brain’s cortex may provide a solution to the complex riddle of Parkinson’s, according to researchers who have found a link between pro-inflammatory biomarkers and the severity of symptoms such as fatigue, depression and anxiety in patients with the chronic disease.Lena Brundin of Michigan State University’s College of Human Medicine was part of a research team that measured inflammatory markers found in cerebrospinal fluid samples of Parkinson’s patients and members of a control group.”The degree of neuroinflammation was significantly associated with more severe depression, fatigue, and cognitive impairment even after controlling for factors such as age, gender and disease duration,” said Brundin, an associate professor in the college and a researcher with the Van Andel Institute.”By investigating associations between inflammatory markers and non-motor symptoms we hope to gain further insight into this area, which in turn could lead to new treatment options.”The results of the study were published in the journal Brain, Behavior, and Immunity.Inflammation in the brain long has been suspected to be involved in the development of Parkinson’s disease, specifically in non-motor symptoms such as depression, fatigue and cognitive impairment. Recent research suggests inflammation could drive cell death and that developing new drugs that target this inflammation might slow disease progression.Parkinson´s disease is the second most common degenerative disorder of the central nervous system; the causes of the disease and its development are not yet fully understood.”The few previous studies investigating inflammatory markers in the cerebrospinal fluid of Parkinson’s patients have been conducted on comparatively small numbers of subjects, and often without a healthy control group for comparison,” Brundin said.In the study, 87 Parkinson’s patients were enrolled between 2008 and 2012. For the control group, 37 individuals were recruited. Participants underwent a general physical exam and routine blood screening. Researchers looked at the following markers: C-reactive protein, interleukin-6, tumor necrosis factor-alpha, eotaxin, interferon gamma-induced protein-10, monocyte chemotactic protein-1 and macrophage inflammatory protein 1-β.The study was carried out in collaboration with researchers from Lund University in Sweden, Skåne University Hospital in Sweden and the Mayo Clinic College of Medicine in Florida.

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