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Roxanne Khamsi New evidence adds weight to the theory that one of the most deadly forms of brain cancer, called malignant glioma, is caused when stem cells deep within the brain begin to proliferate abnormally, researchers have announced. Special receptors on the surfaces of these cells trigger cancerous cell division in response to a particular growth hormone, the team's experiments in mice reveal. Absence of this hormone caused such tumours to shrink, they discovered, raising hopes for a potential treatment. When diagnosed with malignant gliomas, the sufferer typically has just 14 months to live. There is currently no effective treatment for the fast-spreading illness. Arturo Alvarez-Buylla at the University of California in San Francisco, US, and colleagues conducted post-mortem examinations of the brains of three people without the illness. Chemical tests on nerve stem-cells in a deep region of the brain, known as the sub-ventricular zone, revealed the existence of receptors for a growth hormone known as PDGF on the cell surfaces. The PDGF receptors on these stem cells are the same as those found in cells from malignant brain tumours, comments Charles Stiles of the Dana-Farber Cancer Institute in Boston, Massachusetts, US. He says this strengthens the argument that malignant gliomas result when brain stem cells regenerate abnormally. © Copyright Reed Business Information Ltd.

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 9152 - Posted: 06.24.2010

A particularly aggressive form of brain tumor called a glioma may be vulnerable to a drug currently used to treat Crohn's disease, according to a new study in mice. The finding is good news to scientists looking for better treatment options for a cancer that is almost always fatal. The drug exploits a weakness of glioma cells. While most cells take in a necessary amino acid called cystine through a variety of pathways, a team led by Harald Sontheimer, a neuroscientist with the University of Alabama at Birmingham, has discovered that glioma cells have only one mechanism for grabbing the amino acid. Earlier studies elsewhere found that cystine intake in leukemia cells is impaired by sulfasalazine, a drug used to treat diseases such as Crohn's, which causes inflammation of the intestinal tract. So, Sontheimer and colleagues wondered if the drug would cut off the cystine supply to glioma tumors. To test the theory, the researchers first injected mice with malignant human glial tissue. After the tissue developed into tumors, the team divided the mice into three groups. Two groups got sulfasalazine for either 1 or 3 weeks, and a control group received saline. Within 48 hours of receiving the drug, mice in the sulfasalazine group showed biochemical signs that glioma cells were affected. And within a matter of weeks, the size of their tumors had shrunk dramatically. The drug also increased the animals' survival rate. Mice in the control group showed no improvement, the team reports 27 July in the Journal of Neuroscience. Copyright © 2005 by the American Association for the Advancement of Science

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 7695 - Posted: 06.24.2010

Roxanne Khamsi Can a controversial medicine called Lorenzo's oil really reduce the risk of developing a rare brain disease? After years of hope and provisional evidence, experts are publishing scans from children who started this therapy more than a decade ago. They say the positive results will quiet sceptics and prove the oil's worth. In 1984, Augusto and Michaela Odone learned that their son, Lorenzo, suffered from a genetic disorder known as adrenoleukodystrophy, or ALD. The prognosis was frightening: children diagnosed with ALD experience neurological deterioration and typically die from the illness within a few years. Faced with a lack of treatment options for their son, the Odones began pouring over books in the library for more information. They learned that ALD is related to an abnormal accumulation of very-long-chain fatty acids, particularly in the nervous system of the body. Although they tried to cut these fatty acids from their son's diet, his body continued producing them. The literature convinced them that giving their son a different fatty acid, an oily liquid known as oleic acid, would inhibit the synthesis of long chains of saturated fats. It works simply by keeping enzymes busy making chains of unsaturated fats instead. The Odones later improved their formula by using a modified form of rapeseed oil, which seems to keep the enzymes even busier. Their medicine, which improved the health of their ailing son and inspired a Hollywood movie in the early 1990s, became known as 'Lorenzo's oil'. ©2005 Nature Publishing Group

Related chapters from BN: Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Related chapters from MM:Chapter 2: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 7623 - Posted: 06.24.2010

NEW ORLEANS --Glial cells once had a reputation as the support staff for neurons, the real movers and shakers in the nervous system. In recent years, however, researchers have gleaned hints that glia, which comprise about 90% of the cells in the brain, do more than just maintenance work. New findings presented here last week at the annual meeting of the Society for Neuroscience suggest that in the crucial task of building synapses--the contact points that allow neurons to talk to one another--glia may even run the show. The study firms up earlier evidence that glial cells called astrocytes instruct neurons to make synapses and identifies the first extracellular signal known to spur synapse formation in the brain. "That's a pretty big deal," says Michael Ehlers, a neuroscientist at Duke University in Durham, North Carolina. A clue that glia might be the source of the signal to build synapses came in 2001, when Ben Barres and colleagues at Stanford University reported that lab-grown rat neurons make more synapses in the presence of astrocytes (Science , 26 January 2001, p. 657). To hunt for the chemical messenger, postdocs Karen Christopherson and Erik Ullian in Barres's lab grew astrocytes in culture and filtered the solution bathing the cells before adding it to neurons. To their surprise, these experiments indicated that the chemical that spurs synapse building was a whopper--more than 300 kilodaltons. Copyright © 2003 by the American Association for the Advancement of Science.

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 4555 - Posted: 06.24.2010

For the brain to stay online, it needs quick delivery of oxygen and energy. Now, neuroscientists have identified the brain cells that order blood supply for humming parts of the brain. Understanding the link between brain activity and changes in blood flow is crucial to further improve clinical brain scans, such as functional magnetic resonance imaging (MRI), which chart changes in brain activity via measurements of blood flow. Once dismissed as mere scaffolding in the brain, starlike cells called astrocytes are stepping into the limelight. Astrocytes are far more abundant than the electrically powered neurons, and each one features entangled fingerlike processes connected to more than a thousand nerve cells. Positioned close to the neuronal chat sites, the synapses, astrocytes sense neuronal activity and can even influence it, a fact that researchers have come to appreciate in recent years. Astrocytes are also hooked up to the fine network of capillaries that feed neurons, but their interaction with blood vessels has remained mysterious. Copyright © 2002 by the American Association for the Advancement of Science.

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 3093 - Posted: 06.24.2010

NewScientist.com news service The controversial do-it-yourself medicine that inspired the heart-rending movie Lorenzo's Oil has finally been proved to work. The new research ends years of uncertainty about the treatment and demolishes the claims of experts who repeatedly said it was a worthless quack remedy. New Scientist has learned that Hugo Moser, the neurologist and doctor played by Peter Ustinov in the film, will on Saturday unveil the positive conclusions of a 10-year investigation into the oil's effects on a group of boys affected with the same genetic condition as Lorenzo. Normally carriers of the genetic defect are at high risk of developing adrenoleukodystrophy, causing them to progressively lose the ability to move, hear, speak and - finally - breathe. Some victims, like Lorenzo Odone portrayed in the film, get the childhood form which usually kills within just two years. Others get the adult form of the disease, which strikes people in their late twenties and acts more slowly. © Copyright Reed Business Information Ltd.

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System; Chapter 2: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 2725 - Posted: 06.24.2010

It is often the quiet, supportive types who wield real power. Star-shaped brain cells called astrocytes, usually dismissed as support cells for the attention-grabbing neurons, now seem to control the growth of new neurons in adult brains. The find brings scientists closer to understanding the forces that control neuron growth in adults and could lead to ways to treat neurodegenerative diseases or spinal cord injuries. Astrocytes reside throughout the nervous system, filling in the spaces between neurons, the "wires" that pass the system's messages. Astrocytes were thought to constitute protective scaffolding and a nutrition source that help keep neurons healthy. But recently astrocytes have begun to shed their inert image. In the last few years, scientists have found that the supposedly placid cells help neurons form connections with each other (ScienceNOW, 26 January 2001) and might even be stem cells themselves (ScienceNOW, 15 June 1999). Copyright © 2002 by the American Association for the Advancement of Science.

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System; Chapter 4: Development of the Brain
Link ID: 2001 - Posted: 06.24.2010

Scientists have pinpointed a mutated gene as key to the development of some types of glioma brain tumour. The mutation leads to hugely increased levels of a chemical in the brain, which seems to feed the cancer. The Nature study suggests that detecting higher levels of the chemical could provide doctors with a useful diagnostic tool. It also raises hopes that blocking production of the chemical might prevent the cancer getting worse. People with particular brain tumours, such as lower-grade gliomas, often carry a mutated version of a gene that controls production of an enzyme called IDH1. The latest study, by US firm Agios Pharmaceuticals, shows that these mutations change the way the enzyme works and result in the build-up of high levels of a chemical called 2-hydroxyglutarate (2HG) in the brain. Researchers found malignant glioma samples with IDH1 mutations had 100 times more 2HG than similar samples from patients without the mutation. They said measuring 2HG levels could be used to help identify patients with IDH1 mutant brain tumours. Writing in the journal, the researchers said: "This will be important for prognosis as patients with IDH1 mutations live longer than patients with gliomas characterised by other mutations. "In addition, patients with lower-grade gliomas may benefit by the therapeutic inhibition of 2HG production. Inhibition of 2HG production by mutant IDH1 might slow or halt conversion of lower-grade glioma into lethal secondary glioblastoma, changing the course of the disease." (C)BBC

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 13492 - Posted: 11.24.2009

Scientists at Cambridge University have made a major breakthrough researching brain tumours in children. For the first time a sequence of DNA present in around two-thirds of the most common tumour has been pinpointed. Pilocytic astrocytomas is diagnosed in 145 children from five to 19 every year, with nearly 40 cases untreatable. As little is known about the causes and genetics of brain tumours, it is hoped the findings could lead to better treatment. Professor Peter Collins, who led the research at Cambridge University, carried out genetic scans on 44 pilocytic astrocytoma and found a DNA sequence rearranged on a chromosome in the majority of the samples. The rearrangement creates a fusion gene, a hybrid created from two separate genes. It is the first time fusion activity has been associated with a brain tumour. Professor Collins said: "If we can diagnose exactly which type of brain tumour a child has as early as possible, the tumour is more likely to be treated successfully. We also hope the findings will mean it is possible to create therapies in the future that block the activity of the fusion gene and halt the growth of tumour cells." (C)BBC

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 12200 - Posted: 11.01.2008

Researchers have developed a "man-made" scorpion venom to be used in the treatment of brain tumours. The venom is used as a carrier to deliver radioactive iodine into tumour cells left behind after surgery has removed the bulk of the tumour. So far the technique has been tested in 18 patients and further trials are under way, a report in the Journal of Clinical Oncology says. Initial findings suggest the treatment is well-tolerated and may be effective. Gliomas are a particularly aggressive form of brain tumours, with only 8% of patients surviving two years and 3% surviving five years from the time of diagnosis. Despite advances in surgery, radiotherapy and chemotherapy, there has been little improvement in length of survival for patients with gliomas. Researchers at Cedars-Sinai Medical Center, in California, carried out a study using TM-601, a synthetic version of a peptide, that naturally occurs in the venom of the Giant Yellow Israeli scorpion. Unlike many substances, the peptide can pass through the bloodstream into the brain and can bind to glioma cells. Patients in the study first had surgery to remove their tumour. Then 14 to 28 days later, a single, low dose of TM-601 with radioactive iodine attached was injected into the cavity from which the tumour had been removed. (C)BBC

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System; Chapter 3: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Link ID: 9186 - Posted: 07.31.2006

A vaccine has been developed which may be able to fight the most aggressive form of brain tumour, scientists say. US researchers say their vaccine increased survival times for the 23 glioblastoma multiforme patients they tested it on by at least 18 months. Only four patients went on to die from the cancer, the study to be presented at a meeting of experts in the US said. A larger trial of the jab, which works by targeting a protein thought to drive the tumour's spread, is now planned. It uses an artificial form of the protein, which is found on the outside of 30-50% of tumours, to alert the immune system to its presence and attack it. The brain is tricked into thinking the protein, known as EGFRvIII, is foreign, and fighter cells in the immune system are sent in. Amy Heimberger, assistant professor of neurosurgery at the MD Anderson Cancer Center in Texas, said the vaccine was an easy-to-use "off-the-shelf" treatment that could potentially help half of all patients with glioblastoma multiforme (GBM). She said results from the trial showed the vaccine significantly delays the progression of tumours until the cancer finds a new way to grow. But when tumours did grow again they did not display the EGFRvIII protein which led researchers to conclude that the vaccine had worked. Professor Heimberger said: "This is a proof of concept, and optimal use of the vaccine may be with chemotherapy to further retard progression. "Still, this is exciting because people have been trying to use immunotherapy against gliomas for a long time." (C)BBC

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 8855 - Posted: 05.01.2006

By Ker Than A new study finds that a cell once believed to serve neurons instead may perform the crucial function of regulating blood flow in the brain. The discovery challenges a basic assumption in neuroscience and could have implications for interpreting brain scans and understanding what occurs during brain trauma and Alzheimer's disease. Oxygen is the main fuel of biological cells. It is transported throughout the body by way of the circulatory system. Not surprisingly, the brain is one of the most voracious consumers of oxygen, and a basic assumption in neuroscience is that the more active a brain region is, the more oxygen (and thus blood) its neurons require. This assumption forms the foundation for sophisticated brain imaging techniques such as PET and functional MRI scans. By scanning the brain while subjects perform certain tasks, scientists have been able to pinpoint specialized brain regions for phenomena such as emotion or language. Star-shaped brain cells called astrocytes were traditionally thought of as housekeeping cells that helped nourish the brain under the direction of the neurons. The new study found that the astrocytes can directly control blood flow without being told. 2006 LiveScience.com.

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 8370 - Posted: 01.11.2006

Scientists at New York University School of Medicine report in a new study that they have identified the molecular switch that turns on the production of myelin, the fatty insulation around nerve cells that ensures swift and efficient communication in the nervous system. The study, published in the September 1, 2005, issue of the journal Neuron, may provide a new avenue for treating nervous system diseases such as multiple sclerosis, which are associated with damage to myelin. A team led by James L. Salzer, M.D., Ph.D., Professor of Cell Biology and Neurology at NYU School of Medicine, identified the long-sought factor that determines whether or not nerve cells will be wrapped in thick layers of myelin, producing the biological equivalent of a jelly roll. Using a sophisticated system for growing nerve cells in laboratory dishes, the team identified a gene called neuregulin as the myelin signal. This signal directs Schwann cells, the nervous system's cellular architects, to build elaborate sheaths of myelin around the axons of nerve cells. Axons are the long cable-like arms of nerve cells that send messages to other cells. The construction of myelin sheath has been called one of the most beautiful examples of cell specialization in nature. Myelin forms the so-called white matter in the nervous system and constitutes 50 percent of the weight of the brain. It is also an important component of the spinal cord, and of nerves in other parts of the body. It has been known for almost 170 years that there are two kinds of axons --one is wrapped in myelin and appears white and the other is not and appears gray.

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System; Chapter 2: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 7831 - Posted: 09.01.2005

Scientists have identified a chemical that can sneak through the blood-brain barrier to treat tumours. The barrier exists to prevent toxic substances getting into the brain, which makes it hard to deliver drugs. Researchers found enough of the chemical, JV-1-36, could bypass the guard to block tumour growth. The University of Saint Louis study, in Proceedings of the National Academy of Science, suggests the compound may also be useful in treating other cancers. The team carried out tests on mice who had had malignant glioblastomas, the most common form of brain tumour, implanted. They then gave an intravenous injection of JV-1-36, which inhibits the effect of the hypothalamic growth hormone-releasing hormone (GHRH). GHRH's role should be to trigger the hormone that makes children grow, but it has also been found to fuel the growth of cancerous tumours. Receptors for the hormone have been found in other cancer cells including breast, ovary, prostate, pancreas and colon. The researchers found that the P-gp system, which acts as an extra "security guard" at the blood brain barrier and usually keeps anti-cancer drugs out of the brain, blocked some of the JV-1-36, but let much of it pass into the brain. The researchers say the compounds gets into the brain by dissolving into the cell membranes which comprise the blood-brain barrier, and not being picked up by P-gp. They say this appears to be because it is not recognised as being a "foreign" substance. (C)BBC

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System; Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System; Chapter 8: Hormones and Sex
Link ID: 7807 - Posted: 08.27.2005

Researchers from the Max Planck Institute for Medical Research in Heidelberg and the Max Planck Institute of Experimental Medicine in Goettingen (Germany) have uncovered the behaviour of microglial cells in the brain. In the current online edition of Science (Science, Epub ahead of print, 14. April 2005) they report on the busy action of these immune defense cells in the normal brain and their rapid response to cerebral hemorrhage in the first few hours following injury. Their imaging approach is transferable to other models of disease, and monitoring microglia behaviour under such circumstances promises to substantially enhance our knowledge about brain pathologies. Microglial cells are the primary immunocompetent cells in the brain. They are the first responsive element to any kind of brain damage or injury. Microglia are critically involved, for example, in neurodegenerative diseases and stroke. So far, microglial cells have been studied in vitro, i.e. outside the living organism. As a result, key aspects of microglia function have remained elusive such as their behavior in the intact brain or their immediate response to brain injury. Now a German team of researchers from two Max Planck Institutes in Heidelberg and Goettingen (Germany) report a breakthrough in the study of microglial cells in vivo. They uncovered the behaviour of microglial cells in the intact brain by making use of two key technologies: two-photon microscopy and a transgenic mouse model. While mice employed in their experiments were genetically modified to produce a green fluorescent protein (GFP), infrared laser light was used to excite GFPs and thus to visualize stained cells in the micoscope via detection of emitted fluorescent light - even through the intact mouse skullcap. Their findings appear in this weeks online edition of Science (Epub ahead of print).

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System; Chapter 11: Emotions, Aggression, and Stress
Link ID: 7206 - Posted: 04.16.2005

Traditionally viewed as supporting actors, cells known as glia may be essential for the normal development of nerve cells responsible for hearing and balance, according to new University of Utah research. The study is reported in the January 6, 2005 issue of Neuron and is co-authored by scientists at the University of Washington. "Using zebrafish as a model, we've demonstrated that glial cells play a previously unidentified role in regulating the development of sensory hair cell precursors -- the specialized neurons found in the inner ear of humans that make hearing possible. This research increases our understanding of how nerve cells develop and whether it may be possible to regenerate these types of cells in humans one day," said Tatjana Piotrowski, Ph.D., assistant professor of neurobiology and anatomy at the University of Utah School of Medicine. Scientists long have known that glial cells, or simply glia, are essential for healthy nerve cells. However, in the last 10 years scientists have learned that glia aren't just "glue" holding nerve cells together. Glia communicate with each other and even influence synapse formation between neurons. Piotrowski's research in zebrafish focuses on the development of sensory neurons known as hair cells. Like humans, zebrafish use hair cells to detect sound and motion. However, in humans hair cells are buried deep inside the inner ear making them difficult to access. Hair cells in zebrafish are located on the surface of their body and help the fish swim in groups and avoid predators.

Related chapters from BN: Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 9: Hearing, Balance, Taste, and Smell
Related chapters from MM:Chapter 2: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 6: Hearing, Balance, Taste, and Smell
Link ID: 6663 - Posted: 01.06.2005

Scientists have developed a treatment which may be effective against the most common and deadly form of brain cancer. Glioblastoma multiforme (GBM) usually grows so quickly that it kills within a year of diagnosis, and neither surgery, drugs or radiotherapy can stop it. But a team from Cedars-Sinai Medical Center in Los Angeles has boosted survival of lab rats with the tumour by injecting them with a protein. Details are published in the journal Molecular Therapy. The researchers used a genetically modified virus to deliver a small protein called hsFlt3L into the brains of lab rats who had developed GBM. They found that the protein increased the number of immune cells in the brain, and significantly slowed tumour growth. Seven out of 10 rats given a high dose of the protein survived for over a year. There were no signs of adverse side effects. In contrast, rats treated with a dummy injection died from their tumours within one week. Among rats treated with hsFlt3L, 33% were completely tumour free at three months, while all those who survived for six months or longer had no tumours at all. (C) BBC

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 6547 - Posted: 12.07.2004

ITHACA, N.Y. -- A laser-based microscopy technique may have settled a long-standing debate among neuroscientists about how brain cells process energy -- while explaining what's really happening in PET (positron emission tomography) imaging and offering a better way to observe the damage that strokes and neurodegenerative diseases, such as Alzheimer's, wreak on brain cells. Multi-photon microscopy scans by Cornell University biophysicists of living brain tissue, as reported in the latest issue of Science (July 2, 2004), reveal exactly how and when neurons (the cells that do the thinking) and astrocytes (the starburst-shaped glial cells that service neurons) interact to burn oxygen and glucose, after astrocytes make lactate from glucose in the bloodstream, to meet the extraordinary energy demands of the brain. Based on imaging of two different energy states of NADH (nicotinamide adenine dinucleotide, a coenzyme involved in brain-cell metabolism), the Cornell biophysicists say they have both confirmed and redefined the controversial "astrocyte-neuron lactate shuttle" hypothesis for brain energy metabolism. "Over the past decade scientists have passionately debated whether the activated brain burns glucose completely to water or incompletely to lactate," said Karl A. Kasischke, M.D., lead author of the Science paper titled "Neural Activity Triggers Neuronal Oxidative Metabolism Followed by Astrocytic Glycolysis."

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 5742 - Posted: 07.02.2004

For the first time, researchers are characterizing the molecular processes that turn brain cancer deadly, and their work may result in a diagnostic test that can predict patient survival. The research, by scientists at The University of Texas M. D. Anderson Cancer Center demonstrates that degree of loss of a crucial tumor suppressor gene, the AP-2( transcription factor, correlates with progression of different human gliomas. For example, researchers found that normal brain tissue, as well as grade II gliomas, maintained expression of AP-2(, whereas 96 percent of grade III glioma, and almost 99 percent of grade IV glioma had lost AP-2(. "Although previous molecular markers have been identified in malignant gliomas, none have exhibited such a strong correlation with progression, indicating the pivotal role of this gene," says Amy Heimberger, M.D., assistant professor in the Department of Neurosurgery.

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 3658 - Posted: 04.06.2003

A new model for the Parkinson related illness multiple system atrophy In this month's issue of EMBO Reports Kahle et al. describe how they genetically engineered a mouse to show pathological symptoms similar to those of human patients suffering from the neural disease Multiple System Atrophy (MSA), also known as Shy-Drager-Syndrome. The model could help researchers to develop and test new efficient drugs against this wide spread disease. More than 100,000 Europeans and 100,000 US-Americans suffer from MSA. Affected individuals either show symptoms similar to those of patients suffering from Parkinson's Disease or have a strong deterioration in their sense of balance. For this reason the disease is often diagnosed incorrectly. Doctors know very little about the pathology of the disease. However, one characteristic is that some brain cells show abnormal changes. Affected mature oligodendrocytes, the cells that form the isolating outer layer surrounding nerve fibers, produce a small protein called alpha-synuclein. They deposit this protein in the form of pathological structures called glial cytoplasmic inclusions.

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 2230 - Posted: 06.10.2002