By Meredith Wadman The hallmark brain damage in Parkinson’s disease is thought to be the work of a misfolded, rogue protein that spreads from brain cell to brain cell like an infection. Now, researchers have found that the normal form of the protein—α-synuclein (αS)—may actually defend the intestines against invaders by marshaling key immune cells. But chronic intestinal infections could ultimately cause Parkinson’s, the scientists suggest, if αS migrates from overloaded nerves in the gut wall to the brain. “The gut-brain immune axis seems to be on a cusp of an explosion of new insights, and this work offers an exceptionally exciting new hypothesis,” says Charles Bevins, an expert in intestinal immunity at the University of California, Davis, who was not involved with the study. The normal function of αS has long been a mystery. Though the protein is known to accumulate in toxic clumps in the brain and the nerves of the gut wall in patients with Parkinson’s disease, no one was sure what it did in healthy people. Noting that a region of the αS molecule behaves similarly to small, microbe-targeting proteins that are part of the body’s immune defenses, Michael Zasloff, an immunologist at Georgetown University Medical Center in Washington, D.C., set out to find whether αS, too, might help fend off microbial invaders. © 2017 American Association for the Advancement of Science

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity; Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 23784 - Posted: 06.28.2017

By Alice Klein EVIDENCE that Parkinson’s disease may be an autoimmune disorder could lead to new ways to treat the illness. Parkinson’s begins with abnormal clumping of a protein called synuclein in the brain. Neighbouring dopamine-producing neurons then die, causing tremors and difficulty moving. The prevailing wisdom has been that these neurons die from a toxic reaction to synuclein deposits. However, Parkinson’s has been linked to some gene variants that affect how the immune system works, leading to an alternative theory that synuclein causes Parkinson’s by triggering the immune system to attack the brain. An argument against this theory has been that brain cells are safe from immune system attack, because most neurons don’t have antigens – the markers immune cells use to recognise a target. But by studying postmortem brain tissue samples, David Sulzer at Columbia University and his team have discovered that dopamine-producing neurons do display antigens. The team has now conducted blood tests to reveal that people with Parkinson’s show an immune response to these antigens, while people who don’t have the condition do not (Nature, DOI: 10.1038/nature22815). These findings suggest Parkinson’s may be an autoimmune disorder, in which the immune system mistakenly attacks part of the body. There have been hints before that the immune system is involved in Parkinson’s, but this is the first evidence that it plays a major pathological role, says Roger Barker at the University of Cambridge. “It would be an attractive target for therapeutic intervention,” he says. However, it isn’t clear yet if the immune response directly causes neuron death, or if it is merely a side effect of the disease. Sulzer’s team plans to try blocking the autoimmune response in Parkinson’s, to see if this can stop the disease progressing. © Copyright New Scientist Ltd.

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 11: Emotions, Aggression, and Stress
Link ID: 23760 - Posted: 06.22.2017

Parkinson’s disease is commonly thought of as a movement disorder, but after years of living with the disease, approximately 25 percent of patients also experience deficits in cognition that impair function. A newly developed research tool may help predict a patient’s risk for developing dementia and could enable clinical trials aimed at finding treatments to prevent the cognitive effects of the disease. The research was published in Lancet Neurology and was partially funded by the National Institute of Neurological Disorders and Stroke (NINDS), part of the National Institutes of Health. “This study includes both genetic and clinical assessments from multiple groups of patients, and it represents a significant step forward in our ability to effectively model one of the most troublesome non-motor aspects of Parkinson’s disease,” said Margaret Sutherland, Ph.D., program director at the NINDS. For the study, a team of researchers led by Clemens Scherzer, M.D., combined data from 3,200 people with Parkinson’s disease, representing more than 25,000 individual clinical assessments and evaluated seven known clinical and genetic risk factors associated with developing dementia. From this information, they built a computer-based risk calculator that may predict the chance that an individual with Parkinson’s will develop cognitive deficits. Dr. Scherzer is head of the Neurogenomics Lab and Parkinson Personalized Medicine Program at Harvard Medical School and a member of the Ann Romney Center for Neurologic Diseases at Brigham and Women’s Hospital, Boston.

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23759 - Posted: 06.22.2017

Jon Hamilton Researchers are working to revive a radical treatment for Parkinson's disease. The treatment involves transplanting healthy brain cells to replace cells killed off by the disease. It's an approach that was tried decades ago and then set aside after disappointing results. Now, groups in Europe, the U.S. and Asia are preparing to try again, using cells they believe are safer and more effective. "There have been massive advances," says Claire Henchcliffe, a neurologist at Weill Cornell Medicine in New York. "I'm optimistic." "We are very optimistic about ability of [the new] cells to improve patients' symptoms," says Viviane Tabar, a neurosurgeon and stem cell biologist at Memorial Sloan Kettering Cancer Center in New York. Henchcliffe and Tabar joined several other prominent scientists to describe plans to revive brain cell transplants during a session Tuesday at the International Society for Stem Cell Research meeting in Boston. Their upbeat message marks a dramatic turnaround for the approach. During the 1980s and 1990s, researchers used cells taken directly from the brains of aborted fetuses to treat hundreds of Parkinson's patients. The goal was to halt the disease. © 2017 npr

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 13: Memory, Learning, and Development
Link ID: 23738 - Posted: 06.14.2017

By Clare Wilson Would you have pig cells implanted in your brain? Some people with Parkinson’s disease have, in the hope it will stop their disease progressing. The approach is still in the early stages of testing, but initial results from four people look promising, with all showing some improvement 18 months after surgery. People with Parkinson’s disease, which causes tremors and difficulty moving, usually get worse over time. The disease is caused by the gradual loss of brain cells that make dopamine, a compound that helps control our movements. Current medicines replace the missing dopamine, but their effectiveness wears off over the years. So Living Cell Technologies, based in Auckland, New Zealand, has been developing a treatment that uses cells from the choroid plexus in pigs. This brain structure makes a cocktail of growth factors and signalling molecules known to help keep nerve cells healthy. Last month, surgery was completed on a further 18 people in a placebo-controlled trial, using the choroid plexus cell implants. The hope is that compounds made by these cells will nourish the remaining dopamine-producing cells in the patients’ brains, slowing further loss. © Copyright New Scientist Ltd.

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 13: Memory, Learning, and Development
Link ID: 23731 - Posted: 06.12.2017

Mo Costandi Since 1997, more than 100,000 Parkinson’s Disease patients have been treated with deep brain stimulation (DBS), a surgical technique that involves the implantation of ultra-thin wire electrodes. The implanted device, sometimes referred to as a ‘brain pacemaker’, delivers electrical pulses to a structure called the subthalamic nucleus, located near the centre of the brain, and effectively alleviates many of the physical symptoms of the disease, such as tremor, muscle rigidity, and slowed movements. DBS is generally safe but, like any surgical procedure, comes with some risks. First and foremost, it is highly invasive, requiring small holes to be drilled in the patient’s skull, through which the electrodes are inserted. Potential complications of this include infection, stroke, and bleeding on the brain. The electrodes, which are implanted for long periods of time, sometimes move out of place; they can also cause swelling at the implantation site; and the wire connecting them to the battery, typically placed under the skin of the chest, can erode, all of which require additional surgical procedures. Now, researchers at the Massachusetts Institute of Technology have a developed a new method that can stimulate cells deep inside the brain non-invasively, using multiple electric fields applied from outside the organ. In a study published today in the journal Neuron, they show that the method can selectively stimulate deep brain structures in live mice, without affecting the activity of cells in the overlying regions, and also that it can be easily adjusted to evoke movements by stimulation of the motor cortex. © 2017 Guardian News and Media Limited o

Related chapters from BP7e: Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 5: The Sensorimotor System
Link ID: 23700 - Posted: 06.02.2017

By: Ted Dinan, M.D., Ph.D, and John F. Cryan, Ph.D. O ver the past few years, the gut microbiota has been implicated in developmental disorders such as schizophrenia and autism, neurodegenerative disorders such as Alzheimer’s disease and Parkinson’s disease, mood disorders such as depression, and even addiction disorders. It now seems strange that for so many decades we viewed the gut microbiota as bacteria that did us no harm but were of little benefit. This erroneous view has been radically transformed into the belief that the gut microbiota is, in effect, a virtual organ of immense importance. What we’ve learned is that what is commonly referred to as “the brain-gut-microbiota axis” is a bidirectional system that enables gut microbes to communicate with the brain and the brain to communicate back to the gut. It may be hard to believe that the microbes in the gut collectively weigh around three pounds—the approximate weight of the adult human brain—and contain ten times the number of cells in our bodies and over 100 times as many genes as our genome. 1 If the essential microbial genes were to be incorporated into our genomes, it is likely that our cells would not be large enough for the extra DNA. Many of those genes in our microbiota are important for brain development and function; they enable gut bacteria to synthesize numerous neurotransmitters and neuromodulators such as γ-aminobutyric acid (GABA), serotonin, dopamine, and short-chain fatty acids. While some of these compounds act locally in the gut, many products of the microbiota are transported widely and are necessary for the proper functioning of diverse organs. This is a two-way interaction: gut microbes are dependent on us for their nourishment. Any pathological process that reduces or increases food intake has implications for our microbes. © 2017 The Dana Foundation. All Rights Reserved.

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity; Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 23636 - Posted: 05.19.2017

By Andy Coghlan Using a virus to reprogram cells in the brain could be a radical way to treat Parkinson’s disease. People with Parkinson’s have difficulty controlling their movements due to the death of neurons that make dopamine, a brain signalling chemical. Transplants of fetal cells have shown promise for replacing these dead neurons in people with the disease, and a trial is currently under way. But the transplant tissue comes from aborted pregnancies, meaning it is in short supply, and some people may find this ethically difficult. Recipients of these cells have to take immunosuppressant drugs too. Ernest Arenas, at the Karolinska Institute in Stockholm, Sweden, and his team have found a new way to replace lost dopamine-making neurons. They injected a virus into the brains of mice whose dopamine neurons had been destroyed. This virus had been engineered to carry four genes for reprogramming astrocytes – the brain’s support cells – into dopamine neurons. Five weeks later, the team saw improvements in how the mice moved. “They walked better and their gait showed less asymmetry than controls,” says Arenas. This is the first study to show that reprogramming cells in the living brain can lead to such improvements, he says. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23488 - Posted: 04.14.2017

By Knvul Sheikh For the past five decades pharmaceutical drugs like levodopa have been the gold standard for treating Parkinson’s disease. These medications alleviate motor symptoms of the disease, but none of them can cure it. Patients with Parkinson’s continue to lose dopamine neurons critical to the motor control centers of the brain. Eventually the drugs become ineffective and patients’ tremors get worse. They experience a loss of balance and a debilitating stiffness takes over their legs. To replace the lost dopamine neurons, scientists have begun investigating stem cell therapy as a potential treatment or even a cure. But embryonic cells and adult stem cells have proved difficult to harness and transplant into the brain. Now a study from the Karolinska Institute in Stockholm shows it is possible to coax the brain’s own astrocytes—cells that typically support and nurture neurons—into producing a new generation of dopamine neurons. The reprogrammed cells display several of the properties and functions of native dopamine neurons and could alter the course of Parkinson’s, according to the researchers. “You can directly reprogram a cell that is already inside the brain and change the function in such a way that you can improve neurological symptoms,” says senior author Ernest Arenas, a professor of medical biochemistry at Karolinska. Previously, scientists had to nudge specialized cells like neurons into becoming pluripotent cells before they could develop a different kind of specialized cell, he says. It was like having to erase all the written instructions for how a cell should develop and what job it should do and then rewriting them all over again. But Arenas and his team found a way to convert the instructions into a different set of commands without erasing them. © 2017 Scientific American

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity; Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 23475 - Posted: 04.11.2017

By NICHOLAS BAKALAR Hepatitis infection may increase the risk for Parkinson’s disease, though the reasons for the link remain unknown. British investigators used records of 100,390 patients hospitalized with various forms of hepatitis or H.I.V. from 1999 to 2011. They compared Parkinson’s incidence in these patients with incidence in more than six million people admitted for medical or surgical conditions like cataracts, knee replacement or varicose veins. The study, in Neurology, found that people with hepatitis B had a 76 percent higher risk of having Parkinson’s, and people with hepatitis C a 51 percent higher risk, than the control group. Those with other forms of hepatitis or H.I.V. had no increased risk. The study was restricted to hospitalized patients, and the authors did not have detailed information about the severity and treatment of the diseases. “We can’t be sure what is underlying this association,” said the lead author, Dr. Julia Pakpoor, a researcher at the University of Oxford. “It could be the treatment for the hepatitis, or it could be that Parkinson’s and hepatitis have common risk factors we haven’t identified.” A different kind of study would be needed, she said, to determine possible mechanisms that might be involved. © 2017 The New York Times Company

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23430 - Posted: 03.31.2017

By Timothy Revell A smartphone app that uses deep learning lets people with Parkinson’s disease test their symptoms at home in just 4 minutes. The app could help people monitor the disease’s progression more closely, and uncover how lifestyle factors may affect their symptoms. “There’s very little understanding as to how Parkinson’s arises, and patients say that every day the condition is different,” says George Roussos at Birkbeck, University of London. People report symptom changes related to everything from exercise to socialising to diet, but it’s not yet possible to build a solid picture of how these factors interact. “To understand these differences, we need to monitor the condition regularly, in a quick and easy way, over a long period of time,” says Roussos. People with Parkinson’s usually only see a specialist once or twice a year. This makes it hard to track the disease progression in an individual in detail, and means that side effects of medication such as deterioration of mood can go unnoticed. With their Android app, called CloudUPDRS, Roussos and his colleagues want to make it easier to track symptoms and flag potential problems earlier. Similar to how a clinician would conduct a Parkinson’s severity test, the app includes both self-assessment questions and physical tests using a smartphone’s sensors. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23313 - Posted: 03.04.2017

Swedish researchers say a simple blood test is effective at differentiating symptoms of Parkinson's disease from similar disorders, but it isn't ready for clinical use. In its early stages, neurologists say Parkinson's is difficult to distinguish from rarer disorders, called atypical parkinsonian disorders. They have overlapping symptoms that tend to worsen more quickly and are more likely to lead to death. Researchers are on the hunt for biomarkers to help diagnosis these disorders. One potential biomarker, a nerve protein that can be detected when nerve cells die, is found in higher concentrations in spinal fluid collected by lumbar puncture. Now medical scientists have also found the protein in less invasive blood tests. For the study published in Wednesday's online issue of the journal Neurology, Dr. Oskar Hansson of Sweden's Lund University and his team examined 504 people in three groups. Two of the groups, in England and Sweden, included healthy people and those who had been living with one of the disorders for an average of four to six years. The third group of 109 patients had the diseases for three years or less. "The results of the present study strongly indicate that NfL when measured in blood can be used to distinguish between patients with Parkinson's disease and patients with progressive supranuclear palsy multiple system atrophy and corticobasal degeneration with high diagnostic accuracy," the study's authors said. ©2017 CBC/Radio-Canada.

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23206 - Posted: 02.09.2017

By JANE E. BRODY Susan Sills, a Brooklyn artist who until recently made life-size cutouts on plywood using a power saw, long suspected she might be at risk for developing Parkinson’s disease. Both her mother and grandfather had this neurological movement disorder, and she knew that it sometimes runs in families. So she was not surprised when at age 72 she first noticed hand tremors and a neurologist confirmed that she had the disease. But to watch her in action three years later, it would be hard for a layperson to tell. She stands straight, walks briskly, speaks in clarion tones and maintains a schedule that could tire someone half her age. Having wisely put the power saw aside, Ms. Sills now makes intricately designed art jewelry. She is also a docent at the Brooklyn Museum, participates in a cooperative art gallery and assists her husband’s business by entertaining customers. Ms. Sills attributes her energy and well-being partly to the medication she takes but primarily to the hours she spends working out with a physical therapist and personal trainer, who have helped her develop an exercise regimen that, while not a cure, can alleviate Parkinson’s symptoms and slow progression of the disease. “The exercises opened me up,” said Ms. Sills, allowing such symptoms as small steps, slow movements and tiny, cramped handwriting to subside. “The earlier people begin exercising after a Parkinson’s diagnosis, and the higher the intensity of exercise they achieve, the better they are,” Marilyn Moffat, a physical therapist on the faculty of New York University, said. “Many different activities have been shown to be beneficial, including cycling, boxing, dancing and walking forward and backward on a treadmill. If someone doesn’t like one activity, there are others that can have equally good results.” © 2017 The New York Times Company

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23132 - Posted: 01.23.2017

Parkinson’s disease, a chronic, progressive movement disorder characterized by tremors and stiffness, is not considered a fatal disease in and of itself, though it may reduce life expectancy by a modest amount. It is often said that people die “with” Parkinson’s rather than “of” the disease. “People who are healthy when diagnosed will generally live about as long as other people in their age cohort,” said James Beck, the vice president for scientific affairs at the Parkinson’s Disease Foundation, which is involved in research, education and advocacy. “It is not a death sentence.” Since Parkinson’s generally affects people later in life — patients are typically given a diagnosis in their 60s — patients often die of unrelated age-related diseases like cancer, heart disease or stroke. But the most common cause of death in those with Parkinson’s is pneumonia, because the disease impairs patients’ ability to swallow, putting them at risk for inhaling or aspirating food or liquids into their lungs, leading to aspiration pneumonia. Since Parkinson’s also impairs mobility and balance, those with the disease are also at high risk for falls and accidents, which can trigger a cascade of medical problems, including being bedridden and developing pneumonia, Dr. Beck said. In its advanced stages, the disease can make walking and talking difficult and cause other problems not related to movement, including cognitive impairment. Patients often cannot care for themselves and need assistance carrying out simple activities of daily living. One long-term study followed a group of 142 Parkinson’s patients after they were given their diagnosis; their mean age at diagnosis was around 70. The researchers found that 23 percent were generally doing well 10 years later, meaning they could maintain their balance and did not have dementia. But over half of the patients in the original group had died, with the most common cause related to Parkinson’s being pneumonia. © 2017 The New York Times Company

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23094 - Posted: 01.13.2017

By DANNY HAKIM LONDON — Syngenta, the Swiss pesticide giant, claims on its website that data from an influential 2011 study shows that farmers who use the weed killer paraquat are less likely to develop Parkinson’s disease than the general population. However, Syngenta’s claim is at odds with the actual findings of the study, according to two of its authors. The 2011 study, carried out by the National Institutes of Health and researchers from other institutions around the world, found that people who used paraquat or another pesticide, called rotenone, were roughly two and a half times more likely to develop Parkinson’s. The work is known as the Farming and Movement Evaluation, or FAME, study. It drew on a sweeping United States government project called the Agricultural Heath Study, which tracked more than 80,000 farmers and their spouses, as well as other people who applied pesticides, in Iowa and North Carolina. The FAME researchers identified 115 people from the Agricultural Health Study who developed Parkinson’s, and studied 110 of them who provided information on the pesticides they used. The study was influential even among some people who had been skeptics of a connection between the chemicals and the disease. Gary W. Miller, a professor of environmental health at Emory University, referred to a link between Parkinson’s and paraquat as a “red herring” in a 2007 publication. But while Dr. Miller said in a recent email exchange that he had concerns about some previous research making the connection, “the FAME data are strong and should be considered.” He said the study “appears to show a connection between paraquat exposure and Parkinson’s disease.” Because of the prominence of the FAME study, Syngenta addresses it on one of its websites, paraquat.com. Syngenta claims that the study shows that only 115 people had Parkinson’s out of the more than 80,000 people in the broader Agricultural Health Study. Therefore, “the incidence of Parkinson’s disease” in the study “appears to be lower than in the general U.S. population,” Syngenta says. © 2016 The New York Times Company

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Link ID: 23016 - Posted: 12.23.2016

By Israel Robledo As has often been said, with great power comes great responsibility. As we saw in the recent election, social media is a great example of a powerful medium that can change minds and change lives but can also give credibility to false or misguiding information. As someone diagnosed with Parkinson’s disease (PD) nine years ago, I’ve thrilled at seeing social media’s growing power as an agent for good. As our advocacy community has grown, social media has allowed for more information to be circulated in the PD community than ever before, and has become a vital link through which we share experiences, raise awareness about quality of life issues, point people to clinical trials, spread knowledge about cutting-edge research—and importantly, raise critical dollars to fund it. Connecting our community more tightly together has underscored the important role each of us can play in finding an eventual cure. A downside to the awesome power of this platform comes from not knowing or perhaps not caring about the source of information shared on social media. Just as “fake news” has flourished in an environment where speed, rather than accuracy, is what counts, patients—who are understandably vulnerable to hopeful reports about their disease—must recognize that not everything they read is equally credible. In my years of advocating for PD-related causes, hundreds of so-called “miracles” have been announced, all of which have proven to have disappointing results. © 2016 Scientific American

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 22950 - Posted: 12.05.2016

By Clare Wilson WE HAVE been thinking about Parkinson’s disease all wrong. The condition may arise from damage to the gut, not the brain. If the idea is correct, it opens the door to new ways of treating the disease before symptoms occur. “That would be game-changing,” says David Burn at Newcastle University, UK. “There are lots of different mechanisms that could potentially stop the spread.” Parkinson’s disease involves the death of neurons deep within the brain, causing tremors, stiffness and difficulty moving. While there are drugs that ease these symptoms, they become less effective as the disease progresses. One of the hallmarks of the condition is deposits of insoluble fibres of a substance called synuclein. Normally found as small soluble molecules in healthy nerve cells, in people with Parkinson’s, something causes the synuclein molecules to warp into a different shape, making them clump together as fibres. The first clue that this transition may start outside the brain came about a decade ago, when pathologists reported seeing the distinctive synuclein fibres in nerves of the gut during autopsies – both in people with Parkinson’s and in those without symptoms but who had the fibres in their brain. They suggested the trigger was some unknown microbe or toxin. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 22938 - Posted: 12.01.2016

Laura Sanders SAN DIEGO — Over the course of months, clumps of a protein implicated in Parkinson’s disease can travel from the gut into the brains of mice, scientists have found. The results, reported November 14 at the annual meeting of the Society for Neuroscience, suggest that in some cases, Parkinson’s may get its start in the gut. That’s an intriguing concept, says neuroscientist John Cryan of the University College Cork in Ireland. The new study “shows how important gut health can be for brain health and behavior.” Collin Challis of Caltech and colleagues injected clumps of synthetic alpha-synuclein, a protein known to accumulate in the brains of people with Parkinson’s, into mice’s stomachs and intestines. The researchers then tracked alpha-synuclein with a technique called CLARITY, which makes parts of the mice’s bodies transparent. Seven days after the injections, researchers saw alpha-synuclein clumps in the gut. Levels there peaked 21 days after the injections. These weren’t the same alpha-synuclein aggregates that were injected, though. These were new clumps, formed from naturally occurring alpha-synuclein, that researchers believe were coaxed into forming by the synthetic versions in their midst. Also 21 days after the injections, alpha-synuclein clumps seemed to have spread to a part of the brain stem containing nerve cells that make up the vagus nerve, a neural highway that connects the gut to the brain. Sixty days after the injections, alpha-synuclein had accumulated in the midbrain, a region packed with nerve cells that make the chemical messenger dopamine. These are the nerve cells that die in people with Parkinson’s, a progressive brain disorder that affects movement. © Society for Science & the Public 2000 - 2016

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity; Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 22881 - Posted: 11.17.2016

By Karen Weintraub Researchers have long believed that problems with mitochondria—the power plants of cells—underlie some cases of Parkinson’s disease. Now a new study details those problems, and suggests that they may form a common thread linking previously unexplained cases of the disease with those caused by different genetic anomalies or toxins. Finding a common mechanism behind different suspected causes of Parkinson’s suggests that there might also be a common means to measure, treat or cure it, says Marco Baptista, research director at the nonprofit Michael J. Fox Foundation, a leading center for study and advocacy in the fight against Parkinson’s. The study, published Thursday in Cell Stem Cell, did identify a possible way to reverse the damage of Parkinson’s—but only in individual cells and fruit flies. Finding a treatment that does the same thing in people will be challenging, Baptista says. Roughly one million Americans have Parkinson’s disease, which is characterized by motor problems and can cause other symptoms including cognitive and gastrointestinal difficulties. About 1 to 2 percent of cases are linked to mutations in the LRRK2 gene, with far fewer associated with genes known as PINK1 and Parkin. Exposure to environmental factors such as toxic chemicals can also lead to Parkinson’s, although most cases have no obvious cause. In the new paper Xinnan Wang, an assistant professor of neurosurgery at Stanford University, and her colleagues show that mitochondria are underpowered in several types of Parkinson’s and that these mitochondria also release toxic chemicals. Looking at fly models of the disease as well as cells taken from patients, the researchers found that they could correct these problems and reverse neurodegeneration if they reduced levels of a protein involved in mitochondrial activity. © 2016 Scientific American

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 22642 - Posted: 09.10.2016

Researchers may have discovered a method of detecting changes in the eye which could identify Parkinson's disease before its symptoms develop. Scientists at University College London (UCL) say their early animal tests could lead to a cheap and non-invasive way to spot the disease. Parkinson's affects 1 in 500 people and is the second most common neurodegenerative disease worldwide. The charity Parkinson's UK welcomed the research as a "significant step". The researchers examined rats and found that changes could be seen at the back of their eyes before visible symptoms occurred. Professor Francesca Cordeiro who led the research said it was a "potentially revolutionary breakthrough in the early diagnosis and treatment of one of the world's most debilitating diseases". "These tests mean we might be able to intervene much earlier and more effectively treat people with this devastating condition." Symptoms of Parkinson's include tremors and muscle stiffness, slowness of movement and a reduced quality of life. These symptoms usually only emerge after brain cells have been damaged. But there is currently no brain scan, or blood test, that can definitively diagnose Parkinson's disease. Parkinson's does not directly cause people to die, but symptoms do get worse over time. © 2016 BBC

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 22577 - Posted: 08.20.2016