Links for Keyword: Stroke

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'I would just be too exhausted:' Post-stroke fatigue common and hidden

By Amina Zafar, CBC News Senator Murray Sinclair suffered a mild stroke 10 years ago, while he was still serving as a justice in Manitoba. He got swift treatment, but says for weeks after even simple tasks left him exhausted. It's a hidden issue many stroke survivors experience, according to a new report. A stroke happens in about one in 10,000 adults under the age of 64, the group says. Sinclair, who experienced his stroke in 2007 at the age of 56, recalls waking up feeling dizzy and fuzzy headed. He had trouble getting into his robes for court and found he was bumping into a desk and doorway. Typing with his left hand was also difficult. Sinclair chalked it up to lack of sleep. After court, he called his family doctor in Winnipeg. The doctor performed a few co-ordination tests, immediately administered Aspirin and sent him to the emergency department where he was diagnosed, treated and released that night with medication and follow-up appointments arranged. "For several weeks thereafter whenever I would do something, if I would just go for a walk or if I would go outside and try to cut the grass, which I couldn't, I would just be too exhausted to finish a task. Or after I'd done a small task I'd just need to lay down or sit down," he recalled in an interview. "Even writing and reading were problematic for a while." ©2017 CBC/Radio-Canada.

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 23715 - Posted: 06.07.2017

A Baffling Brain Defect Is Linked to Gut Bacteria, Scientists Say

By GINA KOLATA Researchers have traced the cause of a baffling brain disorder to a surprising source: a particular type of bacteria living in the gut. Scientists increasingly suspect that the body’s vast community of bacteria — the microbiome — may play a role in the development of a wide variety of diseases, from obesity to perhaps even autism. The new study, published on Wednesday in Nature, is among the first to suggest convincingly that these bacteria may initiate disease in seemingly unrelated organs, and in completely unexpected ways. Researchers “need to be thinking more broadly about the indirect role of the microbiome” in influencing even diseases that have no obvious link to the gut, said Dr. David Relman, professor of microbiology and immunology at Stanford. The researchers studied hereditary cerebral cavernous malformations — blood-filled bubbles that protrude from veins in the brain and can leak blood or burst at any time. The findings do not point to a cure, but they do suggest a way to prevent these brain defects in children who inherit a mutated gene that can cause them. Researchers warned, though, that it is too soon to say whether the potential treatment — antibiotics, followed by a fecal transplant — will work. “Caution, caution, caution,” urged Dr. Mark Ginsberg, a professor of medicine at the University of California, San Diego, who was not involved in the new study. Still, he added, “The findings are very convincing.” When Dr. Mark Kahn, professor of cardiovascular medicine at the University of Pennsylvania’s Perelman School of Medicine, began this work, the microbiome was the last thing on his mind. © 2017 The New York Times Company

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry; Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language; Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 23603 - Posted: 05.11.2017

A Lazarus Patient And The Limits Of A Lifesaving Stroke Procedure

Irina Zhorov On July 17, 2014 Kurt Hinrichs, of Gladstone, Mo., went to bed early. As often happens, he woke in the middle of the night. When he tried to get out of bed, he crashed to the floor, which woke his wife, Alice. "At first it was like, 'What's going on?' " Alice says. "Are you dreaming? Are you sleepwalking?" Kurt wasn't responding to anything Alice asked him, so she called 911. "I [was] thinking, 'this is a nightmare,' " Kurt says. By the time the ambulance arrived, just a few minutes later, Kurt wasn't speaking and his entire right side was paralyzed. Paramedics recognized that Kurt was having a stroke. When they wheeled Kurt out of the house, Alice thought he might never come home again. And if he did, he would be bedridden or in a wheelchair. "I really didn't have a lot of hope that my husband would be normal again, ever," she says. Speeding towards St. Luke's Hospital in Kansas City, Mo., Kurt realized this was no nightmare. He was awake, "but there was something major and massively wrong with me," Kurt says. About 800,000 people suffer strokes every year in the U.S. Most of them are ischemic strokes, caused by a clot which blocks a vessel supplying blood to the brain. If blood can't reach the brain, cells are deprived of oxygen and start to die. © 2017 npr

A 27-year-old has a brain aneurysm that ruptures. Here’s how she recovers.

By Vicky Hallett Anything can happen while you’re performing karaoke at a dive bar in Scotland. As Lauren Marks found out 10 years ago at age 27, that includes having an aneurysm rupture in your brain. After being rushed to the hospital, the American actress/writer underwent emergency surgery that saved her life. But she lost two things that night: a single black high heel and much of her ability to use language. “A Stitch of Time,” her memoir that focuses on the year that followed, offers a deeply personal — and often surprising — perspective on aphasia, the medical term for this kind of communication disorder. The initial sensation, which Marks describes as “The Quiet,” was pleasurable. “The smallest of activities would enthrall me,” she writes. “Dressing myself, I was awed by the orbital distance between cloth and flesh. Brushing my teeth, I was enchanted by the stiffness of the bristles and the sponginess of my gums.” The Quiet, she explains, was what temporarily replaced her inner monologue. It was as muted as her external speech, which was initially limited to about 40 words. Beginning soon after she was stricken, Marks kept a journal, which she describes as initially “this confetti of fractured words.” Today, Marks can’t imagine what compelled her to scribble down “cathrene prussia horse-donk.” On the same page, she also wrote “speshul,” “Tibet” and “chorus.” © 1996-2017 The Washington Post

The Patients We Do Not See

By Dave A. Chokshi, In medicine, we speak of “seeing patients” when we are rounding in the hospital or caring for those who come to our clinics. But what about those people who may be sick but do not seek care? What is our responsibility to the patients we do not see? This question takes on greater urgency in the current political climate, as patients face the threat of losing health insurance. Renewed efforts to repeal and replace the Affordable Care Act leave millions wondering whether they will be covered. For me, as a physician practicing in the safety net, abstract numbers evoke the very real stories of my uninsured patients. One of my patients, whom I’ll call Elsa, had not seen a doctor since immigrating to the United States 15 years ago. That abruptly changed one morning: She awoke to find the room spinning around her and, terrifyingly, she could not articulate the words to explain to her husband what was going on. She was having a stroke. There are many reasons that patients like Elsa may not seek care – until they have no choice. Although she felt no symptoms before her stroke, Elsa was one of about 13 million U.S. adults with undiagnosed high blood pressure. I wondered if making her aware of her blood pressure would have been enough to avoid her suffering. But even if high blood pressure may sit atop the list of problems I write out, from his or her perspective it may not crack the top five. Food security, job stability, child care and affordable housing understandably feel more urgent. Time and again, I have learned that taking care of my patients starts by trying to walk a mile in their shoes. © 2017 Scientific American

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry; Chapter 16: Psychopathology: Biological Basis of Behavior Disorders
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language; Chapter 12: Psychopathology: The Biology of Behavioral Disorders
Link ID: 23555 - Posted: 05.01.2017

Stroke rates appear to be rising steadily in young adults

By Jia Naqvi The rate of stroke among young people has apparently been rising steadily since 1995, according to a study published this week. Hospitalization rates for stroke increased for women between the ages of 18 and 44, and nearly doubled for men in that age range from 1995 through 2012. Using more-detailed data for 2003 through 2012, the researchers found that rates of hospitalizations for acute ischemic stroke increased by nearly 42 percent for men 35 to 44, while rates for women of the same age group increased by 30 percent over the same time, the study published in the JAMA, the Journal of the American Medical Association. Across all adults, including those in older age ranges, stroke was the fifth leading cause of death in 2013. Overall mortality rates from strokes have significantly decreased over the past 50 years due to multiple factors, including better treatment for hypertension and increased use of aspirin, even as incidence of acute ischemic stroke among young adults has been on the rise. The study also looked at stroke risk factors and whether there were any changes in their prevalence from 2003 to 2012. The likelihood of having three or more of five common risk factors — diabetes, hypertension, lipid disorders, obesity and tobacco use — doubled in men and women hospitalized for acute ischemic strokes. © 1996-2017 The Washington Post=

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language; Chapter 13: Memory, Learning, and Development
Link ID: 23496 - Posted: 04.17.2017

Deadly spider venom could ward off stroke brain damage

Ian Sample Science editor Doctors have stumbled on an unlikely source for a drug to ward off brain damage caused by strokes: the venom of one of the deadliest spiders in the world. A bite from an Australian funnel web spider can kill a human in 15 minutes, but a harmless ingredient found in the venom can protect brain cells from being destroyed by a stroke, even when given hours after the event, scientists say. If the compound fares well in human trials, it could become the first drug that doctors have to protect against the devastating loss of neurons that strokes can cause. Researchers discovered the protective molecule by chance as they sequenced the DNA of toxins in the venom of the Darling Downs funnel web spider (Hadronyche infensa) that lives in Queensland and New South Wales. Venom from three spiders was gathered for the study after scientists trapped and “milked exhaustively” three spiders on Orchid beach, about 400km north of Brisbane. The molecule, called Hi1a, stood out because it looked like two copies of another brain cell-protecting chemical stitched together. It was so intriguing that scientists decided to synthesise the compound and test its powers. “It proved to be even more potent,” said Glenn King at the University of Queensland’s centre for pain research. Strokes occur when blood flow to the brain is interrupted and the brain is starved of oxygen. About 85% of strokes are caused by blockages in blood vessels in the brain, with the rest due to bleeds when vessels rupture. Approximately six million people a year die from stroke, making it the second largest cause of death worldwide after heart attacks. © 2017 Guardian News and Media Limited

After A Stroke At 33, A Writer Relies On Journals To Piece Together Her Own Story

After A Stroke At 33, A Writer Relies On Journals To Piece Together Her Own Story On New Year's Eve, 2006, Christine Hyung-Oak Lee developed a splitting headache. She was 33, and her world turned upside down — as in, she literally saw the world upside down. Suddenly, she could hold things in her mind for only 15 minutes at a time. She was a writer who now couldn't recall words or craft sentences. She remembers looking at the phone and thinking to herself: What is the phone number for 911? Days later, she learned she'd had a stroke. "I had a 15-minute short-term memory, like Dory the fish in Finding Nemo," Lee wrote in a Buzzfeed essay chronicling her experience. "My doctors instructed me to log happenings with timestamps in my Moleskine journal. That, they said, would be my working short-term memory. My memento to my mori." Lee used those journals to reconstruct her experience in a new memoir called Tell Me Everything You Don't Remember. She talks with NPR's Scott Simon about the silver linings of memory loss and the unexpected grief that came with her recovery. Interview Highlights On what it's like to have a 15-minute memory You don't even fathom the magnitude of your loss — or at least I didn't. I couldn't plan for the future. I couldn't think of the past. I had no regrets. So it's literally living in the moment. I was experiencing something that people go to yoga and Zen retreats to achieve. So it was quite pleasant. It was not pleasant for the people around me. But in that period of my recovery, where I couldn't remember everything, I think I was incredibly at peace and happy. On having an "invisible" disability It was frustrating. On the one hand, you want people to know: Hey, slow down for me. Hey, I'm going through a crisis. On the other hand, I was also privileged to be disabled in a way that wasn't visible. So people also didn't treat me any differently. So it was very isolating. ... When I told people that I was sick and I needed them to slow down, along with that came this need to explain my position and I ... felt a lot of resentment for having to do with that. © 2017 npr

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language; Chapter 13: Memory, Learning, and Development
Link ID: 23213 - Posted: 02.11.2017

In search of the stroke detector

Robert McCrum Stroke, or “brain attack”, is the third biggest killer in the western world, after cancer and heart failure. The life-changing effects associated with this simple, Anglo-Saxon word are readily explained: a stroke occurs when the blood supply to the brain is disrupted by a blood vessel either bursting or blocking, so that the part of the brain supplied by this blood vessel dies. The brain is a much more complex organ than the heart. While strokes are a common feature of everyday life, precisely how and why they occur is far from straightforward. Each year in the UK, there will be about 50,000 brain attacks. One-third of those affected will die; one-third will be left severely disabled; and about one-third will make some kind of recovery. In the time it takes to read this article, approximately nine people in Britain, from across all age groups, will have suffered a stroke. Or did they? For the brain is not only super-sensitive territory – as the human animal’s command HQ – it is also top secret. Despite extraordinary progress in MRI scans, the brain remains essentially mysterious and the symptoms of its dysfunction can be hard to diagnose with certainty. An elderly man presenting himself at A&E with unsteady gait and a slurring of his words could be suffering a stroke – or he might just be intoxicated. Treat him for the former, and you’ll save his life; treat him as a drunk, and he might die. © 2017 Guardian News and Media Limited

Common 'silent strokes' go undetected, raise concerns about dementia and strokes

By Sheryl Ubelacker, The Canadian Press Posted: Peter Chaban was up early doing dishes one morning in 2012 when he noticed there was water flowing over his hand — but he couldn't feel it. Next thing he knew, he lost all sensation and strength on his left side and dropped to floor. Within seconds he was lying there completely immobilized. By the time the ambulance arrived at his vacation property near Collingwood, Ont., Chaban had recovered. But doctors at the local hospital diagnosed him with a probable transient ischemic attack, or TIA, a type of temporary stroke that leaves no permanent damage. Once he returned home to Toronto, Chaban was sent for an MRI, and the brain scan confirmed that diagnosis. But of more concern was the discovery of "quite a few" lesions in his brain, the result of "silent strokes" that show up as small holes on imaging. When the strokes had occurred and over what time period was a mystery to Chaban, who had experienced no symptoms. That's why, in fact, they're known as silent — patients have no idea they've had a miniature clot or microbleed in the brain that has destroyed a tiny chunk of neurons, but resulted in no loss of function as would typically occur with a full-blown stroke. "I was never aware of any deficits," said Chaban, 64, who retired from his research job at the Hospital for Sick Children three years ago. "When I was employed, I was quite cognitively active. "I was physically very active. I ski, play golf, I played squash until a few years ago. And my health is very good, so the silent strokes hadn't expressed themselves, at least to my awareness." ©2016 CBC/Radio-Canada.

NPR Story Helps Listener Realize She Was Having A Stroke

As 2016 draws to a close, we are re-visiting some of the people we met this year — including one man who survived a stroke at a young age, and a listener who heard his story on the radio. DAVID GREENE, HOST: Now as 2016 draws to a close, we're revisiting some of the people we met this year. And NPR's Rae Ellen Bichell checks back with a man who survived a stroke in his 40s and also a listener who heard his story. RAE ELLEN BICHELL, BYLINE: Back in February, I reported a story about strokes increasing in adults under 50. Troy Hodge, a 43-year-old man living in Maryland, shared his story about having a stroke two years earlier. (SOUNDBITE OF ARCHIVED BROADCAST) TROY HODGE: I remember setting myself on the floor because I was really hot. And I wanted to get some water to splash on my face. BICHELL: When the story aired on MORNING EDITION, the radio waves carried Hodge's voice into the home of Sue Bryson, a teacher in Virginia. SUE BRYSON: It was just a normal Monday morning and I was just getting ready for work and I was listening to NPR. BICHELL: Listening to Hodge's story, Bryson realized that right then, she was having similar symptoms, that she was having a stroke. So she called her neighbors and they took her to the emergency room. BRYSON: I would have never gone to the hospital if I didn't hear your show - never. BICHELL: Bryson is now back in the classroom and Hodge has made some changes. He moved into a bigger apartment. He walks up a flight of stairs each day without his cane to check the mail. He sometimes forgets things. HODGE: Memory's not too bad, I mean, it's... © 2016 npr

New emergency brain procedure saving stroke patients

By Vik Adhopia, CBC News Every eight minutes someone in Canada has a stroke. But the odds of survival are getting better because of a new emergency intervention being offered at 22 hospitals across Canada. Spencer Higdon, 63, successfully received the procedure at Toronto Western Hospital in April after suddenly collapsing in his bathroom. "I was stepping into the shower and I dropped like a tonne of bricks." he said. When he regained consciousness he knew he'd had a stroke. "I couldn't move my right leg, my right arm, I couldn't speak, and I had difficulty moving my head." Physicians confirmed he'd had an ischemic stroke — a blood clot in his brain. Unless the blockage was cleared within a few hours, his paralysis would likely be permanent, or worse, he'd die. Higdon later learned from one of the treating physicians that because of the position of the clot in the brainstem, the consequences of his stroke could have been devastating. "She said it's called 'locked-in syndrome,' where your brain works just fine but nothing else in your body moves. You're lying in a bed and the only way to communicate is through your eyes. And that just horrified me." The procedure used to remove Higdon's clot, known as a thrombectomy, involves feeding a tiny catheter into an artery near the groin, all the way up into the brain and through the blockage. The device is expanded to grab the clot. Then it's pulled out, allowing the blood to flow again. Advanced imaging equipment helps navigate the catheter. For Higdon, the entire procedure took eight minutes, a record for the stroke team at Toronto Western. ©2016 CBC/Radio-Canada.

Stroke Rates Rising in Younger People

By NICHOLAS BAKALAR Stroke rates have been declining in older people over the past 20 years — but have sharply increased in those under 55. Researchers at Rutgers University used data from the New Jersey Department of Health on more than 227,000 hospitalizations for stroke from 1995 through 2014, calculating incidence by age over five-year periods. The findings appeared in the Journal of the American Heart Association. Compared with the 1995-99 period, the rate of stroke in 2010-14 increased by 147 percent in people 35 to 39, by 101 percent in people 40 to 44, by 68 percent in those 45 to 49, and by 23 percent in the 50 to 54 group. Stroke is still far more common in older people. But the rate decreased by 11 percent in those 55 to 59, by 22 percent in the 60 to 64 group, and by 18 percent in people 65 to 69. The reasons are unclear, but the lead author, Joel N. Swerdel, now an epidemiologist with Janssen Pharmaceuticals, said that increasing obesity and diabetes in younger people are probably involved. “For a person 30 to 50, the good news is you ain’t dead yet,” he said. “With behavioral changes, changing diet, increasing exercise, there’s still hope for you. Behavioral change is hard, but this study is an early warning sign.” © 2016 The New York Times Company

Thousands 'miss out on stroke treatment'

By Smitha Mundasad Health reporter About 9,000 stroke patients a year are missing out on a treatment that can prevent disability following a stroke, say UK experts. Clot retrieval can restore blood flow to the brain, preventing some lasting damage, but currently only 600 patients a year get this therapy, they estimate. A national stroke audit reveals part of the problem is a lack of skilled staff to do the procedure. NHS England says stroke patients are receiving high quality care. During a stroke, the blood supplying vital parts of the brain is interrupted. The most common reason is a clot blocking a major blood vessel in the head, although some strokes are caused by a bleed. The longer a part of the brain is starved of blood, the more likely lasting damage - such as paralysis and speech problems - will occur. Expanding mesh While many people with a stroke caused by a clot currently get drugs to help dissolve the blockage, this does not always work completely. Thrombectomy - or clot retrieval - is another method, which aims to remove the clot mechanically. It is a highly skilled operation, and stroke services need to be set up to be able to deliver the treatment. A thin metal wire housing a mesh is inserted into a major artery in the leg and, under X-ray guidance, it is directed to the site of the problem in the brain. The mesh is then expanded, like a miniature fishing net, to trap and remove the clot. 'Once the clot was out, the damage stopped' © 2016 BBC

Moderate Drinking Tied to Lower Stroke Risk

By NICHOLAS BAKALAR Having one or two alcoholic drinks a day is associated with a lower risk of stroke, a review of studies has found. But drinking more than that increases the risk. The analysis, in BMC Medicine, used data from 27 studies. Compared with nondrinkers or occasional drinkers, people who had one or two drinks a day had an 8 percent reduced risk of ischemic stroke. Ischemic strokes, caused by blockage of an artery supplying blood to the brain, account for about 87 percent of all strokes. Heavier drinking, however, increased stroke risk. Having up to four daily drinks led to an 8 percent increased risk of ischemic stroke, and at more than four drinks, the risk increased by 14 percent. Drinking more than four drinks a day also increased the risk of hemorrhagic stroke, the result of a burst or leaking blood vessel in or near the brain, by up to 82 percent. More moderate drinking did not raise hemorrhagic stroke risk. The lead author, Susanna C. Larsson, an associate professor of epidemiology at the Karolinska Institutet in Sweden, warned that alcohol is not health food. “Nondrinkers should not start to drink as a health measure,” she said. “And I wouldn’t recommend that a person who has a drink or two on the weekend increase his consumption.” © 2016 The New York Times Company

Heartburn drugs may raise stroke risk

Laura Beil NEW ORLEANS — Popular heartburn drugs — already under investigation for possible links to dementia, kidney and heart problems (SN: 6/11/16, p. 8) — have a new health concern to add to the list. An analysis of almost 250,000 medical records in Denmark has found an association with stroke. Researchers from the Danish Heart Foundation in Copenhagen studied patients undergoing gastric endoscopy from 1997 to 2012. About 9,500 of all patients studied suffered from ischemic strokes, which occur when a blood clot blocks a blood vessel in the brain. Overall, the risk of stroke was 21 percent higher in patients taking a proton pump inhibitor, a drug that relieves heartburn, the researchers reported November 15 during the American Heart Association’s annual meeting. While those patients also tended to be older and sicker to start with, the level of risk was associated with dose, the researchers found. People taking the lowest drug doses (between 10 and 20 milligrams a day, depending on the drug) did not have a higher risk. At the highest doses, though, Prevacid (more than 60 mg/day) carried a 30 percent higher risk and Protonix (more than 80 mg/day) a 94 percent higher risk. For Prilosec and Nexium, stroke risk fell within that range. Introduced in the 1980s, proton pump inhibitors are available in both prescription and over-the-counter forms. While they are valuable drugs, “their use has been increasing rapidly,” says lead author Thomas Sehested, adding that people often take them for too long, or without a clear reason. Before taking them, he says, “patients need a conversation with their doctor to see if they really need these drugs.” |© Society for Science & the Public 2000 - 2016

Stroke Study Sparks Call for Revamping Emergency Care Plan

By Allison Bond, Although neurologist Amie Hsia was hundreds of miles away from the emergency room team caring for her ailing aunt last February, she knew her symptoms and imaging pointed to a severe stroke. Hsia’s aunt needed treatment fast with a clot-busting medicine and a procedure known as an endovascular thrombectomy, which removes the clot and restores blood flow to oxygen-starved patches of the brain. The hospital caring for her wasn’t equipped to perform the surgery, however, so Hsia insisted she be transferred to a nearby hospital, where the clot was removed from her brain. Hsia’s aunt survived and is able to live independently, despite some remaining symptoms from the stroke. Still, the travel to another hospital cost her valuable time—and could have hurt her in the long run. That’s the implication of a study published Monday in the Journal of the American Medical Association that found that the sooner patients with severe strokes receive a thrombectomy, the less disabled they tend to be three months later. The research indicates that the brain-saving benefits of thrombectomy are most pronounced within the first few hours after signs of a stroke begin, and that these effects decline with each passing hour. To some experts, the study is a call to rejigger the current method of determining where ambulances ought to take stroke patients, which is based solely on proximity. Instead, they say, patients with apparent severe strokes should be rushed to hospitals that perform thrombectomies. © 2016 Scientific America

Stem cell therapy heals injured mouse brain

Scientists and clinicians have long dreamed of helping the injured brain repair itself by creating new neurons, and an innovative NIH-funded study published today in Nature Medicine may bring this goal much closer to reality. A team of researchers has developed a therapeutic technique that dramatically increases the production of nerve cells in mice with stroke-induced brain damage. The therapy relies on the combination of two methods that show promise as treatments for stroke-induced neurological injury. The first consists of surgically grafting human neural stem cells into the damaged area, where they mature into neurons and other brain cells. The second involves administering a compound called 3K3A-APC, which the scientists have shown helps neural stem cells grown in a petri dish develop into neurons. However, it was unclear what effect the molecule, derived from a human protein called activated protein-C (APC), would have in live animals. A month after their strokes, mice that had received both the stem cells and 3K3A-APC performed significantly better on tests of motor and sensory functions compared to mice that received neither or only one of the treatments. In addition, many more of the stem cells survived and matured into neurons in the mice given 3K3A-APC. “This USC-led animal study could pave the way for a potential breakthrough in how we treat people who have experienced a stroke,” added Jim Koenig, Ph.D., a program director at the NIH’s National Institute of Neurological Disorders and Stroke (NINDS), which funded the research. “If the therapy works in humans, it could markedly accelerate the recovery of these patients.”

Gift-giving brain cells are lifeline to injured nerve cells

Laura Sanders Under duress, nerve cells get a little help from their friends. Brain cells called astrocytes send their own energy-producing mitochondria to struggling nerve cells. Those gifts may help the neurons rebound after injuries such as strokes, scientists propose in the July 28 Nature. It was known that astrocytes — star-shaped glial cells that, among other jobs, support neurons — take in and dispose of neurons’ discarded mitochondria. Now it turns out that mitochondria can move the other way, too. This astrocyte-to-neuron transfer is surprising, says neuroscientist Jarek Aronowski of the University of Texas Health Science Center at Houston. “Bottom line: It’s sort of shocking.” Study coauthor Eng Lo of Massachusetts General Hospital and Harvard Medical School cautions that the work is at a very early stage. But he hopes that a deeper understanding of this process might ultimately point out new ways to protect the brain from damage. Mitochondria produce the energy that powers cells in the body. Scientists have spotted the organelles moving into damaged cells in other parts of the body, including the lungs, heart and liver. The new study turns up signs of this mitochondrial generosity in the brain. Astrocytes produce mitochondria and shunt them out into the soup that surrounds cells, Lo and colleagues found. The researchers then put neurons into this mitochondria-rich broth. When starved of glucose and oxygen — a situation that approximates a stroke — the neurons took in the astrocyte-made organelles. |© Society for Science & the Public 2000 - 2016

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry; Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language; Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 22491 - Posted: 07.30.2016

Neurons get fresh ‘batteries’ after stroke

By Emily Underwood If your car’s battery dies, you might call on roadside assistance—or a benevolent bystander—for a jump. When damaged neurons lose their “batteries,” energy-generating mitochondria, they call on a different class of brain cells, astrocytes, for a boost, a new study suggests. These cells respond by donating extra mitochondria to the floundering neurons. The finding, still preliminary, might lead to novel ways to help people recover from stroke or other brain injuries, scientists say. “This is a very interesting and important study because it describes a new mechanism whereby astrocytes may protect neurons,” says Reuven Stein, a neurobiologist at The Rabin Institute of Neurobiology in Tel Aviv, Israel, who was not involved in the study. To keep up with the energy-intensive work of transmitting information throughout the brain, neurons need a lot of mitochondria, the power plants that produce the molecular fuel—ATP—that keeps cells alive and working. Mitochondria must be replaced often in neurons, in a process of self-replication called fission—the organelles were originally microbes captured inside a cell as part of a symbiosis. But if mitochondria are damaged or if they can’t keep up with a cell’s needs, energy supplies can run out, killing the cell. In 2014, researchers published the first evidence that cells can transfer mitochondria in the brain—but it seemed more a matter of throwing out the trash. When neurons expel damaged mitochondria, astrocytes swallow them and break them down. Eng Lo and Kazuhide Hayakawa, both neuroscientsists at Massachusetts General Hospital in Charlestown, wondered whether the transfer could go the other way as well—perhaps astrocytes donated working mitochondria to neurons in distress. Research by other groups supported that idea: A 2012 study, for example, found that stem cells from bone marrow can donate mitochondria to lung cells after severe injury. © 2016 American Association for the Advancement of Science

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