RxPG News Feed for RxPG News

Medical Research Health Special Topics World
  Home
 
   Health
 Aging
 Asian Health
 Events
 Fitness
 Food & Nutrition
 Happiness
 Men's Health
 Mental Health
 Occupational Health
 Parenting
 Public Health
 Sleep Hygiene
 Women's Health
 
   Healthcare
 Africa
 Australia
 Canada Healthcare
 China Healthcare
 India Healthcare
 New Zealand
 South Africa
 UK
 USA
 World Healthcare
 
   Latest Research
 Aging
 Alternative Medicine
 Anaethesia
 Biochemistry
 Biotechnology
 Cancer
 Cardiology
 Clinical Trials
 Cytology
 Dental
 Dermatology
 Embryology
 Endocrinology
 ENT
 Environment
 Epidemiology
 Gastroenterology
 Genetics
 Gynaecology
 Haematology
 Immunology
 Infectious Diseases
 Medicine
 Metabolism
 Microbiology
 Musculoskeletal
 Nephrology
 Neurosciences
  Brain Diseases
   Epilepsy
  Demyelinating Diseases
  Headache
  Memory
  Neurochemistry
  Neurodegenerative Diseases
  Regeneration
  Spinal Cord Diseases
  Stroke
  Taste
  Trigeminal Neuralgia
 Obstetrics
 Ophthalmology
 Orthopedics
 Paediatrics
 Pathology
 Pharmacology
 Physiology
 Physiotherapy
 Psychiatry
 Radiology
 Rheumatology
 Sports Medicine
 Surgery
 Toxicology
 Urology
 
   Medical News
 Awards & Prizes
 Epidemics
 Launch
 Opinion
 Professionals
 
   Special Topics
 Ethics
 Euthanasia
 Evolution
 Feature
 Odd Medical News
 Climate

Last Updated: Oct 11, 2012 - 10:22:56 PM
Research Article
Epilepsy Channel

subscribe to Epilepsy newsletter
Latest Research : Neurosciences : Brain Diseases : Epilepsy

   EMAIL   |   PRINT
Glutamate- involved in blocking response to anti-epileptic medication

Apr 14, 2008 - 1:41:38 PM , Reviewed by: Dr. Sanjukta Acharya
"These findings provide insight into one mechanism that underlies drug resistance in epilepsy and possibly other central nervous system disorders," said Bjoern Bauer, Ph.D., lead author on the publication.

 
[RxPG] Using a rodent model of epilepsy, researchers found one of the body’s own neurotransmitters released during seizures, glutamate, turns on a signaling pathway in the brain that increases production of a protein that could reduce medication entry into the brain. Researchers say this may explain why approximately 30 percent of patients with epilepsy do not respond to antiepileptic medications. The study, conducted by researchers at the National Institute of Environmental Health Sciences (NIEHS), part of the National Institutes of Health, and the University of Minnesota College of Pharmacy and Medical School, in collaboration with Heidrun Potschka’s laboratory at Ludwig-Maximilians-University in Munich, Germany, is available online and will appear in the May 2008, issue of Molecular Pharmacology.

“Our work identifies the mechanism by which seizures increase production of a drug transport protein in the blood brain barrier, known as P-glycoprotein, and suggests new therapeutic targets that could reduce resistance,” said David Miller, Ph.D., a principal investigator in the NIEHS Laboratory of Pharmacology and co-author on the paper.

The blood-brain barrier (BBB), which resides in brain capillaries, is a limiting factor in treatment of many central nervous system disorders. It is altered in epilepsy so that it no longer permits free passage of administered antiepileptic drugs into the brain. Miller explained that P-glycoprotein forms a functional barrier in the BBB that protects the brain by limiting access of foreign chemicals.

“The problem is that the protein does not distinguish well between neurotoxicants and therapeutic drugs, so it can often be an obstacle to the treatment of a number of diseases, including brain cancer,” Miller said. Increased levels of P-glycoprotein in the BBB has been suggested as one probable cause of drug resistance in epilepsy.

Using isolated brain capillaries from mice and rats and an animal model of epilepsy, the researchers found that glutamate, a neurotransmitter released when neurons fire during seizures, turns on a signaling pathway that activates cyclooxygenase-2 (COX-2), causing increased synthesis of P-glycoprotein in these experiments. Increased transporter expression was abolished in COX-2 knockout mice or by COX-2 inhibitors. It has yet to be shown in animals or patients that targeting COX-2 will reduce seizure frequency or increase the effectiveness of anti-epileptic drugs.

"These findings provide insight into one mechanism that underlies drug resistance in epilepsy and possibly other central nervous system disorders," said Bjoern Bauer, Ph.D., lead author on the publication. "Targeting blood-brain barrier signals that increase P-glycoprotein expression rather than the transporter itself suggests a promising way to improve the effectiveness of drugs that are used to treat epilepsy, though more research is needed before new therapies can be developed.”




Publication: Available online and will appear in the May 2008, issue of Molecular Pharmacology.

Advertise in this space for $10 per month. Contact us today.


Related Epilepsy News
High frequency oscillation analysis on EEGs offers a new surgical approach to improve seizure control
Anti-epileptic drugs increase risk of fractures in patients above the age of fifty years
More research and attention needed for epilepsy
Recent - onset seizures affect white matter development
Ethosuximide - most effective treatment for childhood absence epilepsy
Studies focusing on early diagnosis and treatment of epilepsy with minimal side-effects
Sudden Unexpected Death In Epilepsy
Topiramate may increase the risk of birth defects
Glutamate- involved in blocking response to anti-epileptic medication
Responsive Neurostimulator System: An implantable device to treat epilepsy

Subscribe to Epilepsy Newsletter

Enter your email address:


 About Dr. Sanjukta Acharya
This news story has been reviewed by Dr. Sanjukta Acharya before its publication on RxPG News website. Dr. Sanjukta Acharya, MBBS is the chief editor for RxPG News website. She oversees all the medical news submissions and manages the medicine section of the website. She has a special interest in diabetes and endocrinology.
RxPG News is committed to promotion and implementation of Evidence Based Medical Journalism in all channels of mass media including internet.
 Additional information about the news article
The primary mission of the National Institute of Environmental Health Sciences (http://www.niehs.nih.gov) (NIEHS), one of 27 Institutes and Centers at the National Institutes of Health, is to reduce the burden of human illness and disability by understanding how the environment influences the development and progression of human disease.
The National Institutes of Health (NIH) - The Nation's Medical Research Agency - includes 27 Institutes and Centers and is a component of the U. S. Department of Health and Human Services. It is the primary federal agency for conducting and supporting basic, clinical, and translational medical research, and it investigates the causes, treatments, and cures for both common and rare diseases.

Reference: Bauer B, Hartz AM, Pekcec A, Toellner K, Miller DS, Potschka H. Seizure-Induced Upregulation of P-glycoprotein at the Blood-Brain Barrier through Glutamate and COX-2 Signaling. Molecular Pharmacology. 2007 Dec 19 [Epub ahead of print] doi:10.1124/mol.107.041210.
 Feedback
For any corrections of factual information, to contact the editors or to send any medical news or health news press releases, use feedback form

Top of Page

 
Contact us

RxPG Online

Nerve

 

    Full Text RSS

© All rights reserved by RxPG Medical Solutions Private Limited (India)