1. Electrical ‘switch’ in brain’s capillary network monitors activity and controls blood flow

    March 29, 2017 by Ashley

    From the Larner College of Medicine at the University of Vermont press release:

    All it takes is the flip of a protein “switch” within the tiny wire-like capillaries of the brain to increase the blood flow that ensures optimal brain function. New research has uncovered that capillaries have the capacity to both sense brain activity and generate an electrical vasodilatory signal to evoke blood flow and direct nutrients to nourish hard-working neurons.

    These findings were reported online in Nature Neuroscience.

    When there is an increase in brain activity, there is an increase in blood flow, says Thomas Longden, Ph.D., assistant professor of pharmacology at the Larner College of Medicine at the University of Vermont and first author of the study. “The area of the brain covered by the capillaries — the smallest blood vessels in the body — vastly surpasses the area covered by arterioles. This ideally positions them for monitoring neuronal activity and controlling blood flow.”

    Understanding the mechanisms that precisely direct cerebrovascular blood flow to satisfy the brain’s ever-changing energy needs has, to date, eluded scientists. Neurons consume an enormous amount of the body’s energy supplies — about 20 percent — yet lack their own reserves, so are reliant on blood to deliver nutrients. Previously, capillaries were thought to be passive tubes and the arterioles were thought to be the source of action. Now, Longden and colleagues have discovered that capillaries actively control blood flow by acting like a series of wires, transmitting electrical signals to direct blood to the areas that need it most.

    To achieve this feat, the capillary sensory network relies on a protein (an ion channel) that detects increases in potassium during neuronal activity. Increased activity of this channel facilitates the flow of ions across the capillary membrane, thereby creating a small electrical current that generates a negative charge — a rapidly transmitted signal — that communicates the need for additional blood flow to the upstream arterioles, which then results in increased blood flow to the capillaries.

    The team’s study also determined that if the potassium level is too high, this mechanism can be disabled, which may contribute to blood flow disturbances in a broad range of brain disorders.

    “These findings open new avenues in the way we can investigate cerebral diseases with a vascular component,” says co-first author Fabrice Dabertrand, Ph.D., an assistant professor of pharmacology at the University of Vermont’s Larner College of Medicine. Cerebrovascular illnesses like Alzheimer’s disease, CADASIL, and other conditions that cause cognitive decline can, in part, be a consequence of neurons not receiving enough blood flow and therefore not getting sufficient nutrients.

    “If you’re hungry, you’re not able to do your best work; it may be the same for neurons,” says Dabertrand, who adds that the group’s next phase of research will focus on exploring potential pathological factors involved in disabling the capillary potassium-sensing mechanism.

    An image from the Vermont team’s research will be featured on the cover of the May 2017 issue of Nature Neuroscience.


  2. Study suggests PTSD risk can be predicted by hormone levels prior to deployment

    March 26, 2017 by Ashley

    From the UT Austin press release:

    Up to 20 percent of U.S. veterans who served in Iraq and Afghanistan developed symptoms of post-traumatic stress disorder from trauma experienced during wartime, but new neuroscience research from The University of Texas at Austin suggests some soldiers might have a hormonal predisposition to experience such stress-related disorders.

    Cortisol — the stress hormone — is released as part of the body’s flight-or-fight response to life-threatening emergencies. Seminal research in the 1980s connected abnormal cortisol levels to an increased risk for PTSD, but three decades of subsequent research produced a mixed bag of findings, dampening enthusiasm for the role of cortisol as a primary cause of PTSD.

    However, new findings published in the journal Psychoneuroendocrinology point to cortisol’s critical role in the emergence of PTSD, but only when levels of testosterone — one of most important of the male sex hormones — are suppressed, researchers said.

    “Recent evidence points to testosterone’s suppression of cortisol activity, and vice versa. It is becoming clear to many researchers that you can’t understand the effects of one without simultaneously monitoring the activity of the other,” said UT Austin professor of psychology Robert Josephs, the first author of the study. “Prior attempts to link PTSD to cortisol may have failed because the powerful effect that testosterone has on the hormonal regulation of stress was not taken into account.”

    UT Austin researchers used hormone data obtained from saliva samples of 120 U.S. soldiers before deployment and tracked their monthly combat experiences in Iraq to examine the effects of traumatic war-zone stressors and PTSD symptoms over time.

    Before deployment, soldiers’ stress responses were tested in a stressful CO2 inhalation challenge. “Healthy stress responses showed a strong cortisol increase in response to the stressor, whereas abnormal stress responses showed a blunted, nonresponsive change in cortisol,” Josephs said.

    The researchers found that soldiers who had an abnormal cortisol response to the CO2 inhalation challenge were more likely to develop PTSD from war-zone stress. However, soldiers who had an elevated testosterone response to the CO2 inhalation challenge were not likely to develop PTSD, regardless of the soldiers’ cortisol response.

    “The means through which hormones contribute to the development of PTSD and other forms of stress-related mental illness are complex,” said Adam Cobb, a UT Austin clinical psychology doctoral candidate and co-author of the study. “Advancement in this area must involve examining how hormones function together, and with other psychobiological systems, in response to ever-changing environmental demands.”

    Knowing this, the scientists suggest future research could investigate the efficacy of preventative interventions targeting those with at-risk profiles of hormone stress reactivity. “We are still analyzing more data from this project, which we hope will reveal additional insights into risk for combat-related stress disorders and ultimately how to prevent them,” said Michael Telch, clinical psychology professor and corresponding author of the study.


  3. Shared reading can help with chronic pain

    March 23, 2017 by Ashley

    From the University of Liverpool press release:

    A study conducted by researchers from the University of Liverpool, The Reader and the Royal Liverpool University Hospitals Trust, and funded by the British Academy,
    has found that shared reading (SR) can be a useful therapy for chronic pain sufferers.

    The study, led by Dr Josie Billington from the University’s Centre for Research into Reading into Reading, Literature and Society (CRILS) and recently published in the BMJ Journal for Medical Humanities, compared Shared Reading (SR) — a literature-based intervention developed by national charity The Reader — to Cognitive Behavioural Therapy (CBT) as an intervention for chronic pain sufferers.

    Chronic pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage. It is pain which persists for more than six months.

    Usually pain is picked up by specialised cells in your body, and impulses are sent through the nervous system to the brain. What happens in people with chronic pain, however, is that other nerves are recruited into this ‘pain’ pathway which start to fire off messages to the brain when there is no physical stimulus or damage. But the body can ‘unjoin’ again. Nerve blockers (drugs) are one way; Cognitive Behavioural Therapy (CBT) is another — by getting the brain to send new messages back to the body

    Cognitive Behavioural Therapy

    CBT is a talking therapy that can help you manage your problems by changing the way you think and behave. It’s most commonly used to treat anxiety and depression, but can be useful for other mental and physical health problems.

    The current evidence base in respect of chronic pain supports the use of standard psychological interventions, CBT in particular. CBT’s benefits, while useful are shown by recent research to be both limited and short-term.

    Shared Reading is used in a range of environments that have similarities with chronic pain, in that the conditions involved can often be chronic and unsolvable, as in the case of dementia, prisons (people locked in, life halted and future inevitably affected by baggage of past), and severe mental illness (with recurring episodes).

    The model is based on small groups (2-12 people) coming together weekly to read literature — short stories, novels and poetry — together aloud. The reading material ranges across genres and period, and is chosen for its intrinsic interest, not pre-selected with a particular ‘condition’ in mind.

    Validating experiences

    Regular pauses are taken to encourage participants to reflect on what is being read, on the thoughts or memories the book or poem has stirred, or on how the reading matter relates to their own lives.

    Group members participate voluntarily, usually in relation to what is happening in the text itself, and what may be happening within themselves as individuals (personal feelings and thoughts, memories and experiences), responding to the shared presence of the text within social group discussion.

    CBT allowed participants to exchange personal histories of living with chronic pain in ways which validated their experience. However, in CBT, participants focused exclusively on their pain with ‘no thematic deviation’.

    In SR, by contrast, the literature was a trigger to recall and expression of diverse life experiences — of work, childhood, family members, relationships — related to the entire life-span, not merely the time-period affected by pain, or the time-period pre-pain as contrasted with life in the present. This in itself has a potentially therapeutic effect in helping to recover a whole person, not just an ill one.

    Valuable

    As part of the study participants with severe chronic pain symptoms were recruited by the pain clinic at Broadgreen NHS Hospital Trust having given informed consent. A 5-week CBT group and a 22-week SR group for chronic pain patients ran in parallel, with CBT group-members joining the SR group after the completion of CBT.

    The study found that CBT showed evidence of participants ‘managing’ emotions by means of systematic techniques, where Shared Reading (SR) turned passive experience of suffering emotion into articulate contemplation of painful concerns.

    Dr Josie Billington, Deputy Researcher, Centre for Research into Reading, said: “Our study indicated that shared reading could potentially be an alternative to CBT in bringing into conscious awareness areas of emotional pain otherwise passively suffered by chronic pain patients.

    “The encouragement of greater confrontation and tolerance of emotional difficulty that Sharing Reading provides makes it valuable as a longer-term follow-up or adjunct to CBT’s concentration on short-term management of emotion.”


  4. How to get kids to use salad bars at school

    March 21, 2017 by Ashley

    From the BYU press release:

    Thanks to a national initiative, salad bars are showing up in public schools across the country. Now a Brigham Young University researcher is trying to nail down how to get kids to eat from them.

    BYU health sciences professor Lori Spruance studies the impact of salad bars in public schools and has found one helpful tip: teens are more likely to use salad bars if they’re exposed to good, old-fashioned marketing. Students at schools with higher salad bar marketing are nearly three times as likely to use them.

    “Children and adolescents in the United States do not consume the nationally recommended levels of fruits and vegetables,” Spruance said. “Evidence suggests that salad bars in schools can make a big difference. Our goal is to get kids to use them.”

    Some 4,800 salad bars have popped up in public schools around the country according to the Let’s Move Salad Bars to Schools initiative. About 50 percent of high school students have access to salad bars at schools, 39 percent of middle school kids and 31 percent of elementary school children.

    Spruance’s study, published in Health Education and Behavior, followed the salad bar usage of students in 12 public schools in New Orleans. Spruance and coauthors from Tulane University administered surveys to the students and tracked the school environment through personal visits.

    Not only did they find better marketing improved salad bar usage among secondary school students, but they also found female students use salad bars more often than male students, and children who prefer healthy foods use them more frequently.

    “The value of a salad bar program depends on whether students actually use the salad bar,” Spruance said. “But few studies have examined how to make that happen more effectively.”

    Some examples of successful salad bar marketing efforts included signage throughout the school promoting the salad bar, information in school publications and newsletters, and plugs for the salad bar on a school’s digital presence.

    Spruance suggests that schools engage parents in their efforts to improve the school food environment–such as reaching out to parents through newsletters or parent teacher conferences. Of course, she says, offering healthy options at home makes the biggest difference.

    “It takes a lot of effort and time, but most children and adolescents require repeated exposures to food before they will eat them on their own,” Spruance said. “If a child is being exposed to foods at home that are served at school, the child may be more likely to eat those fruits or vegetables at school.”

    Spruance’s research builds off of previous studies that show students are more likely to use salad bars if they are included in the normal serving line.

    There have now been 2,401,500 kids served from salad bars in public schools nationwide. However, only two Utah public schools currently have salad bars funded by the Let’s Move initiative.


  5. Blueberry concentrate improves brain function in older people

    March 20, 2017 by Ashley

    From the University of Exeter press release:

    Blueberries

    Drinking concentrated blueberry juice improves brain function in older people, according to research by the University of Exeter.

    In the study, healthy people aged 65-77 who drank concentrated blueberry juice every day showed improvements in cognitive function, blood flow to the brain and activation of the brain while carrying out cognitive tests.

    There was also evidence suggesting improvement in working memory.

    Blueberries are rich in flavonoids, which possess antioxidant and anti-inflammatory properties.

    Dr Joanna Bowtell, head of Sport and Health Sciences at the University of Exeter, said: “Our cognitive function tends to decline as we get older, but previous research has shown that cognitive function is better preserved in healthy older adults with a diet rich in plant-based foods.

    “In this study we have shown that with just 12 weeks of consuming 30ml of concentrated blueberry juice every day, brain blood flow, brain activation and some aspects of working memory were improved in this group of healthy older adults.”

    Of the 26 healthy adults in the study, 12 were given concentrated blueberry juice — providing the equivalent of 230g of blueberries — once a day, while 14 received a placebo.

    Before and after the 12-week period, participants took a range of cognitive tests while an MRI scanner monitored their brain function and resting brain blood flow was measured.

    Compared to the placebo group, those who took the blueberry supplement showed significant increases in brain activity in brain areas related to the tests.

    The study excluded anyone who said they consumed more than five portions of fruit and vegetables per day, and all participants were told to stick to their normal diet throughout.

    Previous research has shown that risk of dementia is reduced by higher fruit and vegetable intake, and cognitive function is better preserved in healthy older adults with a diet rich in plant-based foods.

    Flavonoids, which are abundant in plants, are likely to be an important component in causing these effects.


  6. Might smartphones help to maintain memory in patients with mild Alzheimer’s disease?

    by Ashley

    From the IOS Press press release:

    The patient is a retired teacher who had reported memory difficulties 12 months prior to the study. These difficulties referred to trouble remembering names and groceries she wanted to purchase, as well as frequently losing her papers and keys. According to the patient and her husband, the main difficulties that she encountered were related to prospective memory (e.g., forgetting medical appointments or to take her medication).

    To help her with her symptoms, Mohamad El Haj, a psychologist and assistant professor at the University of Lille, proposed Google Calendar, a time-management and scheduling calendar service developed by Google. The patient accepted as she was already comfortable using her smartphone. She also declared that she preferred the application as it offers more discrete assistance than a paper-based calendar.

    With the patient and her husband, Dr. El Haj and his colleagues defined several prospective omissions in the patient, such as forgetting her weekly medical appointment, forgetting her weekly bridge game in the community club, and forgetting to go to weekly mass at the church. These omissions were targeted by sending automatic alerts, prompted by Google Calendar, at different times before each event (e.g., the medical appointment).

    The researchers compared omissions before after the use of Google Calendar, they observed less omission after implementing the application.

    The study is the first to suggest positive effects of smartphones applications on everyday life prospective memory in Alzheimer’s disease. The findings, published in Journal of Alzheimer’s disease, are encouraging, however, Dr. El Haj notes that this is a case study and therefore entails a few limitations, including generalizability of the results. The current, anecdotal findings require a larger study, not only to confirm or refute the findings reported here, but also to address challenges such as the long-term benefits of Google calendar.

    Regardless of its potential limitations, Dr. El Haj notes that this study addresses memory loss, the main cognitive hallmark of Alzheimer’s disease and the major concern of the patients and their families. By demonstrating positive effect of Google Calendar on prospective memory in this patient, Dr. El Haj hopes that his study paves the way for exploring the potential of smartphone-integrated memory aids in Alzheimer’s disease. The future generation of patients may be particularly sensitive to the use of smartphones as a tool to alleviate their memory compromise.


  7. Even after treatment, brains of anorexia nervosa patients not fully recovered

    March 19, 2017 by Ashley

    From the University of Colorado Anschutz Medical Campus press release:

    Even after weeks of treatment and considerable weight gain, the brains of adolescent patients with anorexia nervosa remain altered, putting them at risk for possible relapse, according to researchers at the University of Colorado Anschutz Medical Campus.

    The study, published last week in the American Journal of Psychiatry, examined 21 female adolescents before and after treatment for anorexia and found that their brains still had an elevated reward system compared to 21 participants without the eating disorder.

    “That means they are not cured,” said Guido Frank, MD, senior author of the study and associate professor of psychiatry and neuroscience at the University of Colorado School of Medicine. “This disease fundamentally changes the brain response to stimuli in our environment. The brain has to normalize and that takes time.”

    Brain scans of anorexia nervosa patients have implicated central reward circuits that govern appetite and food intake in the disease. This study showed that the reward system was elevated when the patients were underweight and remained so once weight was restored.

    The neurotransmitter dopamine might be the key, researchers said.

    Dopamine mediates reward learning and is suspected of playing a major role in the pathology of anorexia nervosa. Animal studies have shown that food restriction or weight loss enhances dopamine response to rewards.

    With that in mind, Frank, an expert in eating disorders, and his colleagues wanted to see if this heightened brain activity would normalize once the patient regained weight. Study participants, adolescent girls who were between 15 and 16 years old, underwent a series of reward-learning taste tests while their brains were being scanned.

    The results showed that reward responses were higher in adolescents with anorexia nervosa than in those without it. This normalized somewhat after weight gain but still remained elevated.

    At the same time, the study showed that those with anorexia had widespread changes to parts of the brain like the insula, which processes taste along with a number of other functions including body self-awareness.

    The more severely altered the brain, the harder it was to treat the illness, or in other words, the more severely altered the brain, the more difficult it was for the patients to gain weight in treatment.

    Generalized sensitization of brain reward responsiveness may last long into recovery,” the study said. “Whether individuals with anorexia nervosa have a genetic predisposition for such sensitization requires further study.”

    Frank said more studies are also needed to determine if the continued elevated brain response is due to a heightened dopamine reaction to starvation and whether it signals a severe form of anorexia among adolescents that is more resistant to treatment.

    In either case, Frank said the biological markers discovered here could be used to help determine the likelihood of treatment success. They could also point the way toward using drugs that target the dopamine reward system.

    “Anorexia nervosa is hard to treat. It is the third most common chronic illness among teenage girls with a mortality rate 12 times higher than the death rate for all causes of death for females 15-24 years old,” Frank said. “But with studies like this we are learning more and more about what is actually happening in the brain. And if we understand the system, we can develop better strategies to treat the disease.”


  8. Living with children may mean less sleep for women, but not for men

    March 16, 2017 by Ashley

    From the American Academy of Neurology press release:

    New research backs up what many women already know: They’re sleep deprived. Unlike men, a good night’s sleep for women is affected by having children in the house, according to a preliminary study released today that will be presented at the American Academy of Neurology’s 69th Annual Meeting in Boston, April 22 to 28, 2017.

    “I think these findings may bolster those women who say they feel exhausted,” said study author Kelly Sullivan, PhD, of Georgia Southern University in Statesboro, Ga., and a member of the American Academy of Neurology. “Our study found not only are they not sleeping long enough, they also report feeling tired throughout the day.”

    For the study, researchers examined data from a nationwide telephone survey of 5,805 people. Participants were asked how long they slept, with seven to nine hours per day considered optimum and less than six hours considered insufficient. They were also asked how many days they felt tired in the past month.

    Researchers looked at age, race, education, marital status, number of children in the household, income, body mass index, exercise, employment and snoring as possible factors linked to sleep deprivation.

    Among the 2,908 women aged 45 years and younger in the study, researchers found the only factor associated with getting enough sleep was having children in the house, with each child increasing the odds of insufficient sleep by nearly 50 percent.

    For women under 45, 48 percent of women with children reported getting at least seven hours of sleep, compared to 62 percent of women without children.

    No other factors — including exercise, marital status and education — were linked to how long younger women slept.

    The study found that not only was living with children associated with how long younger women slept, but also how often they felt tired. Younger women with children reported feeling tired 14 days per month, on average, compared to 11 days for younger women without children in the household. Having children in the house was not linked to how long men slept.

    “Getting enough sleep is a key component of overall health and can impact the heart, mind and weight,” said Sullivan, “It’s important to learn what is keeping people from getting the rest they need so we can help them work toward better health.”


  9. Study suggests depression symptoms due to chronic sinus disease interfere with productivity

    March 14, 2017 by Ashley

    From the Massachusetts Eye and Ear Infirmary media release:

    Depressed patients with chronic rhinosinusitis (CRS) are more likely to miss days of work or school than those without depression symptoms, according to the results of a new study led by the Sinus Center at Massachusetts Eye and Ear. The findings, published online in Annals of Allergy, Asthma and Immunology, identify depression symptoms as the primary driver of lost days of productivity in patients with CRS, paving the way for more individualized therapy to improve overall quality of life in these patients.

    “In this study, we found that of all symptoms related to CRS — sinus, nasal or otherwise — the severity of depressed mood and depression symptomatology was the predominant factor associated with how often our CRS patients missed work or school due to their CRS,” said senior author Ahmad R. Sedaghat, M.D., Ph.D., a sinus surgeon at Mass. Eye and Ear and assistant professor of otolaryngology at Harvard Medical School. “The severity of even symptoms most typically related to CRS, such as nasal congestion, was not associated with how often our patients missed work or school due to their CRS.”

    One of the more prevalent chronic illnesses in the United States, CRS has been known to cause significant quality of life detriments to affected patients, who often cannot breathe or sleep easily due to obstructed nasal and sinus passages.

    The researchers previously identified four categories of symptoms that dominate CRS — disturbances of sleep, nasal obstruction, ear and facial pain and emotional function. In subsequent studies, they showed that disturbed sleep and ear/facial pain are most associated with overall poorer quality of life.

    In search of an association with lost productivity, the researchers assessed these four categories of symptoms in 107 patients with CRS using a standardized survey. On average, study participants reported three missed days of work or school in a three-month period, or 12 missed days in a year. When the researchers took a closer look at the surveys, they identified emotional symptoms, in which depression symptoms are the strongest feature, as the primary driver of missed days of work or school.

    The researchers were surprised to find that there was not an association between sleep disturbance or nasal obstruction symptoms — symptoms which are more commonly thought of in relation to CRS — with CRS patients missing days of work or school.

    “These findings really point to the fact that specific elements (in this case, symptoms) of CRS may be driving specific disease manifestations or consequences of the disease” Dr. Sedaghat said. In an effort to specifically tailor our CRS treatment to each patient, we have to be cognizant not just of the overall severity of the disease, but also of the severity of individual aspects, symptoms and manifestations of the disease. In this case, we have found that depressed mood, which CRS patients commonly experience, is associated with a particular consequence of the disease — that patients may miss work because of CRS — and these results open the door to exploring interventions directed at depressed mood for reducing productivity losses due to CRS.”


  10. Rapid blood pressure drops in middle age linked to dementia in old age

    by Ashley

    From the Johns Hopkins University Bloomberg School of Public Health media release:

    Middle-aged people who experience temporary blood pressure drops that often cause dizziness upon standing up may be at an increased risk of developing cognitive decline and dementia 20 years later, new Johns Hopkins Bloomberg School of Public Health research suggests.

    The findings, being presented March 10 at the American Heart Association’s EPI|LIFESTYLE 2017 Scientific Sessions in Portland, Ore., suggest that these temporary episodes — known as orthostatic hypotension — may cause lasting damage, possibly because they reduce needed blood flow to the brain. Previous research has suggested a connection between orthostatic hypotension and cognitive decline in older people, but this appears to be the first to look at long-term associations.

    “Even though these episodes are fleeting, they may have impacts that are long lasting,” says study leader Andreea Rawlings, PhD, MS, a post-doctoral researcher in the Department of Epidemiology at the Bloomberg School. “We found that those people who suffered from orthostatic hypotension in middle age were 40 percent more likely to develop dementia than those who did not. It’s a significant finding and we need to better understand just what is happening.”

    An estimated four million to five million Americans currently have dementia and, as the population ages, that number is only expected to grow. There currently is no treatment and no cure for the condition.

    For the study, the researchers analyzed data from the Atherosclerosis Risk in Communities (ARIC) cohort, a study of 15,792 residents in four communities in the United States, who were between the ages of 45 and 64 when the study began in 1987. For this study, they focused on the 11,503 participants at visit one who had no history of coronary heart disease or stroke. After 20 minutes lying down, researchers took the participants’ blood pressure upon standing. Orthostatic hypotension was defined as a drop of 20 mmHg or more in systolic blood pressure or 10 mmHg or more in diastolic blood pressure. Roughly six percent of participants, or 703 people, met the definition.

    These participants, who were on average 54 years old upon enrolling in the study, continued to be followed over the next 20 or more years. People with orthostatic hypotension at the first visit were 40 percent more likely to develop dementia than those who did not have it. They had 15 percent more cognitive decline.

    Rawlings says it is not possible to tease out for certain whether the orthostatic hypotension was an indicator of some other underlying disease or whether the drop in blood pressure itself is the cause, though it is likely that the reduction in blood flow to the brain, however temporary, could have lasting consequences.

    It also wasn’t clear, she says, whether these participants had repeated problems with orthostatic hypotension over many years or whether they had just a brief episode of orthostatic hypotension at the original enrollment visit, as patients were not retested over time.

    “Identifying risk factors for cognitive decline and dementia is important for understanding disease progression, and being able to identify those most at risk gives us possible strategies for prevention and intervention,” Rawlings says. “This is one of those factors worth more investigation.”