Chapter 7. Life-Span Development of the Brain and Behavior

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Catherine Offord The Japanese government’s health ministry has given the go-ahead for a trial of human induced pluripotent stem cells to treat spinal cord injury, Reuters reports today (February 18). Researchers at Keio University plan to recruit four adults who have sustained recent nerve damage in sports or traffic accidents. “It’s been 20 years since I started researching cell treatment. Finally we can start a clinical trial,” Hideyuki Okano of Keio University School of Medicine told a press conference earlier today, The Japan Times reports. “We want to do our best to establish safety and provide the treatment to patients.” The team’s intervention involves removing differentiated cells from patients and reprogramming them via human induced pluripotent stem cells (iPSCs) into neural cells. Clinicians will then inject about 2 million of these cells into each patient’s site of injury. The approach has been successfully tested in a monkey, which recovered the ability to walk after paralysis, according to the Times. It’s not the first time Japan has approved the use of iPSCs in clinical trials. Last year, researchers at Kyoto University launched a trial using the cells to treat Parkinson’s disease. And in 2014, a team at the RIKEN Center for Developmental Biology led the first transplant of retina cells grown from iPSCs to treat a patient’s eye disease. © 1986 - 2019 The Scientist

Keyword: Regeneration; Stem Cells
Link ID: 25976 - Posted: 02.21.2019

Ian Sample Science editor Scientists are developing a radical form of gene therapy that could cure a devastating medical disorder by mending mutations in the brains of foetuses in the womb. The treatment, which has never been attempted before, would involve doctors injecting the feotus’s brain with a harmless virus that infects the neurons and delivers a suite of molecules that correct the genetic faults. Tests suggest that the therapy will be most effective around the second trimester, when their brains are in the early stages of development. “We believe that this could provide a treatment, if not a cure, depending on when it’s injected,” said Mark Zylka, a a neurobiologist at the University of North Carolina. The therapy is aimed at a rare brain disorder known as Angelman syndrome, which affects one in 15,000 births. Children with the condition have small brains and often experience seizures and problems with walking and sleeping. They can live their whole lives without speaking a word. Zylka said children with Angelman syndrome can have such severe sleeping difficulties that parents can feel they must lock them in their rooms at night to prevent them from getting up and having accidents around the house. Healthy people tend to have two copies of every gene in the genetic code, one inherited from their mother and the other from their father. But both copies are not always switched on. For normal brain development, the mother’s copy of a gene called UBE3A is switched on, while the father’s copy is silenced. © 2019 Guardian News & Media Limited

Keyword: Development of the Brain
Link ID: 25975 - Posted: 02.19.2019

By Perri Klass, M.D. A major international study provides new reassurance around the question of whether young children who have anesthesia are more likely to develop learning disabilities The issue has troubled pediatric anesthesiologists and parents for well over a decade, after research on animals suggested that there was a connection. Do the drugs that make it possible to perform vital surgical procedures without pain cause lasting damage to the developing human brain? Several large studies have found ways to tease out the effects of actual surgeries and anesthetic exposures on children. The new study, in the British journal The Lancet, is a randomized controlled trial involving more than 700 infants who needed hernia repairs. The babies, at 28 hospitals in seven countries, were randomly assigned to receive either general anesthesia or regional (spinal) anesthesia for these short operations — the mean duration of general anesthesia was 54 minutes. The study, called the GAS study — for general anesthesia compared to spinal — compared neurodevelopmental outcomes at 5 years of age, and found no significant difference in the children’s performance in the two groups. Dr. Andrew Davidson, a professor in the department of anesthesia at the Royal Children’s Hospital of Melbourne and one of the two lead investigators on the trial, said that this prospective, randomized design allows researchers to avoid many confounding factors that have complicated previous studies, and answer a very specific question. Preliminary data from testing the children at age 2 had shown no significant differences between the groups, and the children were then evaluated at the age of school entry. “If you have an hour of anesthesia as a child, then you are at no greater risk of deficits of cognition at the age of 5,” Dr. Davidson said. “It doesn’t increase the risk of poor neurodevelopmental outcome.” © 2019 The New York Times Company

Keyword: Development of the Brain; Learning & Memory
Link ID: 25972 - Posted: 02.18.2019

A genetic variant found only in people of African descent significantly increases a smoker’s preference for cigarettes containing menthol, a flavor additive. The variant of the MRGPRX4 gene is five to eight times more frequent among smokers who use menthol cigarettes than other smokers, according to an international group of researchers supported by the U.S. Food and Drug Administration and the National Institutes of Health. The multiethnic study is the first to look across all genes to identify genetic vulnerability to menthol cigarettes. The paper was published online in the journal PLOS Genetics (link is external) on Feb. 15. Menthol provides a minty taste and a cooling or soothing sensation, and plays a particularly troubling role in U.S. cigarette smoking patterns. According to the FDA, nearly 20 million people in the United States smoke menthol cigarettes, which are particularly popular among African-American smokers and teen smokers. In the U.S., 86 percent of African-American smokers use menthol cigarettes, compared to less than 30 percent of smokers of European descent. In addition, menthol cigarettes may be harder to quit than other cigarettes. Although not originally the focus of the study, researchers also uncovered clues as to how menthol may reduce the irritation and harshness of smoking cigarettes. “This study sheds light on the molecular mechanisms of how menthol interacts with the body,” said Andrew Griffith, M.D., Ph.D., scientific director and acting deputy director of NIH’s National Institute on Deafness and Other Communications Disorders (NIDCD). “These results can help inform public health strategies to lower the rates of harmful cigarette smoking among groups particularly vulnerable to using menthol cigarettes.”

Keyword: Drug Abuse; Genes & Behavior
Link ID: 25969 - Posted: 02.18.2019

By Pallab Ghosh Science correspondent, BBC News, Washington DC New results suggest ageing brains can potentially be rejuvenated, at least in mice, according to researchers. Very early-stage experiments indicate that drugs can be developed to stop or even reverse mental decline. The results were presented at the 2019 meeting of the American Association for the Advancement of Science. The US and Canadian researchers took two new approaches to trying to prevent the loss of memory and cognitive decline that can come with old age. One team, from the University of California, Berkeley, showed MRI scans which indicated that mental decline may be caused by molecules leaking into the brain. Blood vessels in the brain are different from those in other parts of the body. They protect the organ by allowing only nutrients, oxygen and some drugs to flow through into the brain, but block larger, potentially damaging molecules. This is known as the blood-brain barrier. The scans revealed that this barrier becomes increasingly leaky as we get older. For example, 30-40% of people in their 40s have some disruption to their blood-brain barrier, compared with 60% of 60-year-olds. The scans also showed that the brain was inflamed in the leaky areas. Prof Daniela Kaufer, who leads the Berkeley group, said that young mice altered to have leaky blood-brain barriers showed many signs of aging. She discovered a chemical that stops the damage to the barrier from causing inflammation to the brain. Prof Kaufer told BBC News that not only did the chemical stop the genetically altered young mice from showing signs of aging, it reversed the signs of aging in older mice. © 2019 BBC

Keyword: Alzheimers; Learning & Memory
Link ID: 25966 - Posted: 02.15.2019

By Kelly Servick Rough sleep is bad for your mind—and your heart. It can increase the risk of clogged arteries, which can lead to stroke or heart attacks. But how these two things are connected has been a mystery. Now, a study in mice reveals a link, based on signals the brain sends to bone marrow. If the story holds true in humans, the mechanism could help explain the connection between sleep and other conditions, from obesity to cancer. “Not everyone who is sleep-deprived develops cardiovascular disease,” says Namni Goel, a behavioral neuroscientist at the University of Pennsylvania Perelman School of Medicine in Philadelphia who was not involved in the work. The new mouse work “opens the door for human studies” that could sort out who is most at risk. In many forms of cardiovascular disease, fatty deposits build up on artery walls (a condition called atherosclerosis) and can rupture to cause a stroke or heart attack. Immune cells—in particular, white blood cells called monocytes—also play a key role. They flock to sites where these deposits have damaged blood vessels and they spawn cells that can contribute to the growing plaque. To follow up on the known connection between sleep and heart disease, immunologist Filip Swirski of Harvard Medical School and Massachusetts General Hospital in Boston wanted to explore whether sleep somehow triggered an immune process that spurs this dangerous buildup. © 2019 American Association for the Advancement of Science

Keyword: Sleep; Learning & Memory
Link ID: 25965 - Posted: 02.14.2019

Ian Sample Science editor An experimental drug that bolsters ailing brain cells has raised hopes of a treatment for memory loss, poor decision making and other mental impairments that often strike in old age. The drug could be taken as a daily pill by over-55s if clinical trials, which are expected to start within two years, show that the medicine is safe and effective at preventing memory lapses. Tests in the lab showed that old animals had far better memory skills half an hour after receiving the drug. After two months on the treatment, brain cells which had shrunk in the animals had grown back, scientists found. Etienne Sibille, at the Centre for Addiction and Mental Health in Toronto, said the treatment was aimed not only at the “normal” cognitive decline that leads to senior moments, but at memory loss and mental impairments that commonly afflict people with depression, schizophrenia and Alzheimer’s disease. If the drug did well in human trials, Sibille said it was possible that “anybody over the age of 55-60 who may be at risk of cognitive problems later on could benefit from this treatment”. “Our findings have direct implications for poor cognition in normal ageing,” he said, with the drug potentially improving learning, memory, decision making and essential life planning. “But we see this deficiency across disorders from depression to schizophrenia and Alzheimer’s.” © 2019 Guardian News & Media Limited

Keyword: Alzheimers; Learning & Memory
Link ID: 25964 - Posted: 02.14.2019

By Nicholas Bakalar Chronic inflammation in middle age may lead to memory and thinking problems later in life. Unlike acute inflammation, which arises in response to injury, chronic inflammation persists over months or years. Autoimmune disease, lingering infection, exposure to polluted air, psychological stress and other conditions can all promote chronic inflammation. Researchers did blood tests on 12,336 men and women, average age 57, assigning them an “inflammation composite score” based on white blood cell count, clotting factors and other tests. They also assessed their cognition with standardized tests of memory, processing speed and verbal fluency. The study is in Neurology. After controlling for age, education, blood pressure, cholesterol, heart disease and many other factors, they found that the greater the number of inflammatory factors, the steeper the cognitive decline over 20 years of follow-up. Inflammation was most strongly associated with declines in memory. “We know that dementia starts earlier than the appearance of symptoms,” said the lead author, Keenan A. Walker, a postdoctoral researcher at Johns Hopkins, “and we’ve shown that levels of inflammation matter for dementia risk. Reducing chronic inflammation involves the same health behaviors that we already know are important for other reasons — regular exercise, healthy diet, avoiding excessive weight gain and so on.” © 2019 The New York Times Company

Keyword: Alzheimers; Neuroimmunology
Link ID: 25962 - Posted: 02.14.2019

By Natalie Angier Most female flies take a low-rent approach to parenthood, depositing scores of seed-sized eggs in the trash or on pet scat to hatch, leaving the larvae to fend for themselves. Not so the female tsetse fly. She gestates her young internally, one at a time, and gives birth to them live. When each extravagantly pampered offspring pulls free of her uterus after nine days, fly mother and child are pretty much the same size. “It’s the equivalent of giving birth to an 18-year-old,” said Geoffrey Attardo, an entomologist who studies tsetse flies at the University of California, Davis. The newborn tsetse fly looks like a hand grenade and moves like a Slinky, and if you squeeze it too hard the source of its plumpness becomes clear — or rather a telltale white. The larva, it seems, is just a big bag of milk. “Rupture the gut,” Dr. Attardo said, “and the milk comes spilling out.” And milk it truly is — a nutritional, biochemical and immunological designer fluid that the mother fly’s body has spun from her blood meals and pumped into her uterus, where her developing young greedily gulped it down. Thus fattened on maternal largess, a tsetse fly larva can safely burrow underground and pupate for 30 days before emerging as a full-blown adult with a nasty bite and a notorious capacity to transmit a deadly disease called sleeping sickness. In a recent chemical and genetic analysis of tsetse fly milk, Dr. Attardo and his colleagues were startled to discover how similar it was to the product of the beloved gland that stamps us as mammals. “I was expecting something completely off the wall and different,” he said. “But there are frightening, fascinating overlaps with mammalian milk in the kinds of proteins we see.” © 2019 The New York Times Company

Keyword: Sexual Behavior; Development of the Brain
Link ID: 25955 - Posted: 02.12.2019

By Lisa Rapaport New mothers who have friends ready to step in and help them, tend to have toddlers who score better on cognitive tests than the babies of women with smaller social support networks, a U.S. study suggests. Strong social ties to friends and family have long been linked to better behavioral and physical health outcomes for adults. And plenty of previous research also indicates that infants’ and toddlers’ bonds with caregivers can have a lasting impact on children’s emotional, intellectual and social development. But less is known about how the caregivers’ own social connections might influence early childhood cognitive development. For the current study, researchers examined data on 1,082 mother-child pairs. They questioned women about their family structure, friendships and relationships in their communities and also looked at test results from cognitive assessments done when children were 2 years old. Overall, mothers had an average of 3.5 friends in their social support networks. The kids of mothers with more than that tended to have higher cognitive test scores than the kids of those who had fewer, suggesting “network conditions were significantly associated with early cognitive development in children,” the study authors wrote. © 1996-2019 The Washington Post

Keyword: Sexual Behavior; Development of the Brain
Link ID: 25954 - Posted: 02.12.2019

Sujata Gupta The task was designed to scare the kids. One by one, adults guided children, ranging in age from 3 to 7, into a dimly lit room containing a mysterious covered mound. To build anticipation, the adults intoned, “I have something in here to show you,” or “Let’s be quiet so it doesn’t wake up.” The adult then uncovered the mound — revealed to be a terrarium — and pulled out a realistic looking plastic snake. Throughout the 90-second setup, each child wore a small motion sensor affixed to his or her belt. Those sensors measured the child’s movements, such as when they sped up or twisted around, at 100 times per second. Researchers wanted to see if the movements during a scary situation differed between children diagnosed with depression or anxiety and children without such a diagnosis. It turns out they did. Children with a diagnosis turned further away from the perceived threat — the covered terrarium — than those without a diagnosis. In fact, the sensors could identify very young children who have depression or anxiety about 80 percent of the time, researchers report January 16 in PLOS One. Such a tool could be useful because, even as it’s become widely accepted that children as young as age 3 can suffer from mental health disorders, diagnosis remains difficult. Such children often escape notice because they hold their emotions inside. It’s increasingly clear, though, that these children are at risk of mental and physical health problems later in life, says Lisabeth DiLalla, a developmental psychologist at Southern Illinois University School of Medicine in Carbondale. “The question is: ‘Can we turn that around?’” |© Society for Science & the Public 2000 - 2019

Keyword: Development of the Brain; Depression
Link ID: 25936 - Posted: 02.06.2019

By Jen Gunter Pregnant women are given a long list of medical recommendations that can come across as patriarchal don’ts: Don’t eat raw fish. Don’t consume deli meats. Don’t do hot yoga! Don’t drink. There’s scientific evidence that these activities can have negative impacts on the health of the fetus, but the one that seems to be the source of most debate is alcohol. After all, the French do it, don’t they? And many people born in the 1960s or earlier had mothers who drank. And we’re fine, right? My mother had a fairly regular glass of rye and ginger ale when she was pregnant with me. And she smoked. And I graduated from medical school at the age of 23. So my opinion, especially as someone who believes strongly in a woman’s right to make decisions about her own body, may come as a surprise: It’s medically best not to drink alcohol in pregnancy. Not even a little. The source of that viewpoint? My training and practice as an OB/GYN. Some attribute this abstinence approach to the patriarchy: Clearly we doctors know that moderate alcohol is safe (we don’t!), and we just don’t trust women with that knowledge. According to this theory, we think a woman who hears that an occasional drink is O.K. will blithely go on a bender. (We don’t think that.) Some also say that, in an effort to avoid frivolous lawsuits, doctors advise against alcohol while using a nudge-nudge-wink-wink to insinuate that a glass or two is fine. But this isn’t about sexism (not this time) or dodging litigation. This is about facts. How women use those facts is, of course, their choice. The truth is that fetal alcohol syndrome is far more common than people think, and we have no ability to say accurately what level of alcohol consumption is risk free. © 2019 The New York Times Company

Keyword: Development of the Brain; Drug Abuse
Link ID: 25935 - Posted: 02.06.2019

Catherine Offord Researchers in the UK and New Zealand have created the largest-ever database of protein expression changes associated with Alzheimer’s disease, according to a study published today (February 4) in Communications Biology. The data, which are freely available to researchers online, reveal new insights into the brain areas affected by Alzheimer’s, as well as the molecular pathways leading to the disease. “This database provides a huge opportunity for dementia researchers around the world to progress and to follow-up new areas of biology and develop new treatments,” study coauthor Richard Unwin of the University of Manchester says in a statement. “It’s very exciting to be able to make these data public so scientists can access and use this vital information.” The team analyzed the expression data of more than 5,500 proteins spanning six brain regions in postmortem tissue of nine healthy and nine Alzheimer’s-affected patients. The results provide a map of changes associated with the disease, identifying certain areas of the brain as more affected than others. Heavily affected areas include the hippocampus, the entorhinal cortex, and the cingulate gyrus, the analysis showed. The researchers also found that the cerebellum, an area of the brain thought to be less damaged by Alzheimer’s disease, showed substantial changes in protein expression, but that these changes qualitatively differed from those in other regions. © 1986 - 2019 The Scientist

Keyword: Alzheimers
Link ID: 25934 - Posted: 02.06.2019

By Howard M. Fillit Alzheimer's disease is the sixth leading cause of death in the U.S., and unlike with cancer and heart disease, we lack the tools to effectively diagnose and treat it. In sharp contrast to other illnesses and despite many efforts, huge expense and hundreds of clinical trials, no new treatments have been approved in the past 16 years. The emphasis has been on drugs targeting beta-amyloid proteins, which clump into plaques in the brains of afflicted people. Unfortunately, these approaches have not yet yielded the results we hoped for. So now it is time to target novel pathways to tackle this incredibly complex disease. This has been a challenge because of the absence of affordable and noninvasive tests based on biomarkers that doctors can easily use in their offices. The alternatives have been expensive and invasive spinal taps or neuroimaging tests that can be performed only in a hospital or freestanding radiology office. New biomarkers are needed for specific molecular targets that can be used to subtype patients; for predicting the likelihood that they will acquire Alzheimer's; and possibly for providing a diagnosis even before symptoms are noticeable, enabling prevention. That is, they could do what currently available amyloid positron-emission tomography (PET) scans and cerebrospinal fluid tests do. Biomarkers can also be used to enroll patients in clinical trials directed to a specific target, such as beta-amyloid, and to measure how the body responds to a treatment—as was done most recently by Biogen with its anti-beta-amyloid monoclonal antibody. Ultimately biomarkers can determine which therapies would be most effective for an individual. © 2019 Scientific American

Keyword: Alzheimers
Link ID: 25927 - Posted: 02.02.2019

Laura Sanders Do you floss regularly? A study published January 23 in Science Advances — and the news stories that it inspired — might have scared you into better oral hygiene by claiming to find a link between gum bacteria and Alzheimer’s disease. Those experiments hinted that the gum disease–causing bacteria Porphyromonas gingivalis was present in the brains of a small number of people who died with the degenerative brain disease. Some headlines trumpeted that the cause of Alzheimer’s had finally been found. Enzymes made by P. gingivalis, called gingipains, interact with key Alzheimer’s proteins called amyloid-beta and tau in test tube experiments and in the brains of mice, the researchers found. Gingipains prod A-beta to accumulate and tau to behave abnormally, both signs of Alzheimer’s disease in people, the experiments suggest. And compounds that block gingipains seemed to reduce the amount of A-beta in the infected mice. The findings “offer evidence that P. gingivalis and gingipains in the brain play a central role” in the development of Alzheimer’s disease, the researchers write in their study. The research was paid for and conducted in part by employees of Cortexyme, Inc., a San Francisco–based biotech company that’s developing these compounds. The results fit with an idea that’s gaining traction among Alzheimer’s researchers — that bacteria, viruses and even fungi could spark the disease (SN: 7/21/18, p. 10). But the Science Advances study is far from conclusive, cautions Rudolph Tanzi, an Alzheimer’s researcher at Massachusetts General Hospital in Boston. Science News asked him what the study can, and can’t, answer about Alzheimer’s disease. His responses are edited for length and clarity. |© Society for Science & the Public 2000 - 2019

Keyword: Alzheimers
Link ID: 25920 - Posted: 02.01.2019

Amy Lewis Cynthia Bulik began her scientific career studying childhood depression. But while she was working as a research assistant at the University of Pittsburgh in the 1980s, psychiatrist David Kupfer asked her to help write a book chapter comparing electroencephalography studies in depression and anorexia. As preparation, she shadowed a psychiatrist at a hospital inpatient unit for people with eating disorders. Bulik was intrigued by what she witnessed there. “These people were my age, my sex, and weighed half as much as I did,” she says. “They seemed very eloquent and interactive, but at the same time, in this one area of their psychology and biology, they occupied a completely different space.” Now the founding director of the Center of Excellence for Eating Disorders at the University of North Carolina at Chapel Hill, Bulik has been unraveling the biology behind eating disorders such as anorexia nervosa (AN) ever since. Characterized by extreme caloric restriction resulting in weight loss, an intense fear of gaining weight, and a distorted body image, anorexia has the highest mortality rate of any psychiatric disorder. Death can be a result of various risks associated with the condition, from suicide to heart failure. While many AN sufferers go undiagnosed, making incidence rates hard to pin down, some researchers estimate that up to 2 percent of women and 0.3 percent of men are affected globally. © 1986 - 2019 The Scientist

Keyword: Anorexia & Bulimia; Genes & Behavior
Link ID: 25914 - Posted: 01.29.2019

By Pam Belluck In dementia research, so many paths have led nowhere that any glimmer of optimism is noteworthy. So some experts are heralding the results of a large new study, which found that people with hypertension who received intensive treatment to lower their blood pressure were less likely than those receiving standard blood pressure treatment to develop minor memory and thinking problems that often progress to dementia. The study, published Monday in JAMA, is the first large, randomized clinical trial to find something that can help many older people reduce their risk of mild cognitive impairment — an early stage of faltering function and memory that is a frequent precursor to Alzheimer’s disease and other dementias. The results apply only to those age 50 or older who have elevated blood pressure and who do not have diabetes or a history of stroke. But that’s a condition affecting a lot of people — more than 75 percent of people over 65 have hypertension, the study said. So millions might eventually benefit by reducing not only their risk of heart problems but of cognitive decline, too. “It’s kind of remarkable that they found something,” said Dr. Kristine Yaffe, a professor of psychiatry and neurology at University of California San Francisco, who was not involved in the research. “I think it actually is very exciting because it tells us that by improving vascular health in a comprehensive way, we could actually have an effect on brain health.” © 2019 The New York Times Company

Keyword: Alzheimers
Link ID: 25913 - Posted: 01.29.2019

Aimee Cunningham A sleep-deprived brain is awash in excess amounts of not one but two proteins whose bad behavior is implicated in Alzheimer’s disease. A new study finds excessive amounts of a protein called tau in the fluid that bathes the brain and spinal cord of extremely sleep-deprived adults. Tau, which is tied to nerve cell death, tangles and spreads throughout the brain during Alzheimer’s. An earlier report on these sleepy adults found that the protein amyloid-beta — globs of which dot the brains of Alzheimer’s patients — also increased. Samples of cerebrospinal fluid collected from eight adults, monitored during a night of normal sleep and over the course of 36 hours of sleep deprivation, revealed a 51.5 percent increase in tau in participants robbed of shut-eye. And sleep-deprived mice had twice the amount of tau as well-rested mice, researchers report online January 24 in Science. Earlier work by these researchers had suggested that the quality of sleep might affect tau levels; this time, it’s been linked to duration of sleep. With both A-beta and tau increasing with a lack of sleep, “it certainly argues that treating sleep disorders during mid-life as well as getting appropriate levels of sleep is likely to decrease risk for Alzheimer’s disease,” says coauthor David Holtzman, a neurologist and neuroscientist at Washington University School of Medicine in St. Louis. During sleep, the brain appears to flush out excess proteins and other debris (SN: 7/21/18, p. 22), so perhaps less sleep means that wash cycle is curtailed. |© Society for Science & the Public 2000 - 2019.

Keyword: Sleep; Alzheimers
Link ID: 25904 - Posted: 01.26.2019

By Jocelyn Kaiser Poor oral health is a risk factor for Alzheimer’s disease. What’s not clear is whether gum disease causes the disorder or is merely a result—many patients with dementia can’t take care of their teeth, for example. Now, a privately sponsored study has confirmed that the bacteria that cause gum disease are present in the brains of people with Alzheimer’s, not just in their mouths. The study also finds that in mice, the bacteria trigger brain changes typical of the disease. The provocative findings are the latest in a wave of research suggesting microbial infections may play a role in Alzheimer’s disease. But even some scientists who champion that once-fringy notion aren’t convinced that Porphyromonas gingivalis, the species fingered in the new study, is behind the disorder. “I'm fully on board with the idea that this microbe could be a contributing factor. I'm much less convinced that [it] causes Alzheimer’s disease,” says neurobiologist Robert Moir of the Harvard University–affiliated Massachusetts General Hospital (MGH) in Boston, whose work suggests the β-amyloid protein that forms plaques in the brains of Alzheimer’s patients is a protective response to microbial invaders. The new study, published today in Science Advances, was sponsored by the biotech startup Cortexyme Inc. of South San Francisco, California. Co-founder Stephen Dominy is a psychiatrist who in the 1990s became intrigued by the idea that Alzheimer’s could have an infectious cause. At the time, he was treating people with HIV at the University of California, San Francisco. Some had HIV-related dementia that resolved after they got antiviral drugs. Dominy began a side project looking for P. gingivalis in brain tissue from deceased patients with Alzheimer’s, and—after his work found hints—started the company with entrepreneur Casey Lynch, who had studied Alzheimer’s as a graduate student. © 2018 American Association for the Advancement of Science

Keyword: Alzheimers
Link ID: 25899 - Posted: 01.24.2019

Andrew Scheyer We live in a medicated era. Recent data indicate that more than half of Americans are currently taking prescription drugs. Among pregnant women this number skyrockets to more than 80 percent. One of these women was a 24-year-old from California named Carol, whom I met and befriended through an online drug research forum. After weeks of debilitating morning sickness, persistent pain in her back and hips, and chronic anxiety about becoming a mother, Carol was taking a tranquilizer called alprazolam as needed, plus daily doses of acetaminophen and an anti-nausea drug called metoclopramide. Carol felt uneasy using the medications. Like many Americans and an even greater proportion of Europeans, Carol (who asked that I not use her surname) favors home remedies over pharmaceutical treatments. “I’ll always choose a tea over a pill,” she says. And so, as she sought relief during her pregnancy, she turned to marijuana. In the summer of 2007, Carol was surrounded by people touting the wonders of cannabis as a panacea for diseases from depression to glaucoma and myriad ailments in between—including nausea, pain, and anxiety. Worried that her suboptimal diet and poor sleep could be affecting the development of her child, she considered using small amounts of cannabis instead of the multiple prescription medications suggested by her doctor. Seventy percent of women in the United States believe that there is “slight or no risk of harm” in using can­nabis during pregnancy. © 1986 - 2019 The Scientist

Keyword: Development of the Brain; Drug Abuse
Link ID: 25898 - Posted: 01.24.2019