XML Feed for RxPG News   Add RxPG News Headlines to My Yahoo!   Javascript Syndication for RxPG News

Research Health World General
 
  Home
 
 Latest Research
 Cancer
 Psychiatry
 Genetics
 Surgery
 Aging
 Ophthalmology
  Cornea
  Cataract
  Retina
   ARMD
 Gynaecology
 Neurosciences
 Pharmacology
 Cardiology
 Obstetrics
 Infectious Diseases
 Respiratory Medicine
 Pathology
 Endocrinology
 Immunology
 Nephrology
 Gastroenterology
 Biotechnology
 Radiology
 Dermatology
 Microbiology
 Haematology
 Dental
 ENT
 Environment
 Embryology
 Orthopedics
 Metabolism
 Anaethesia
 Paediatrics
 Public Health
 Urology
 Musculoskeletal
 Clinical Trials
 Physiology
 Biochemistry
 Cytology
 Traumatology
 Rheumatology
 
 Medical News
 Health
 Opinion
 Healthcare
 Professionals
 Launch
 Awards & Prizes
 
 Careers
 Medical
 Nursing
 Dental
 
 Special Topics
 Euthanasia
 Ethics
 Evolution
 Odd Medical News
 Feature
 
 World News
 Tsunami
 Epidemics
 Climate
 Business
 
 India
Search

Last Updated: Nov 18, 2006 - 12:32:53 PM

Retina Channel
subscribe to Retina newsletter

Latest Research : Ophthalmology : Retina

   DISCUSS   |   EMAIL   |   PRINT
Successful tests of new treatments for Leber congenital amaurosis (LCA)
Nov 2, 2005 - 11:21:00 AM, Reviewed by: Dr.

In the current paper, Palczewski (formerly of the University of Washington) examined the effect of combining the two treatments in blind mice that did not have the LRAT enzyme. They report that gene therapy carrying the LRAT gene significantly restored electroretinographic (ERG) responses and pupillary light responses. Pharmacological intervention with orally administered drugs also caused long-lasting restoration of retinal function in LRAT-deficient mice and increased ERG response.

 
A team led by Krzysztof Palczewski, Ph.D., chair of pharmacology at the Case Western Reserve University School of Medicine, has taken the first steps in treating an eye disease causing irreversible congenital blindness in millions of people worldwide by successfully testing two new treatments in mice.

Publishing in this month's open access journal PLoS Medicine, the researchers found that these treatments "provide highly effective and complementary means for restoring retinal function in this animal model of human hereditary blindness."

The disease studied is Leber congenital amaurosis (LCA), characterized by severe loss of vision at birth. Its causes are not fully understood. Researchers believe that the disease might be due to abnormal development of photoreceptor cells in the retina, extremely premature degeneration of these cells, or lack of essential metabolic ingredients necessary for vision in the cells. In a subset of these diseases, it is known that the retina stops functioning due to loss of the lecithin retinol acyl-transferase enzyme (LRAT). LRAT is required for regeneration of a pigment necessary for the eye to detect light.

LCA can be caused by mutations in the gene encoding RPE65, a key protein involved in the production and recycling of 11-cis-retinal in the eye. Currently, there is no treatment for LCA, although previous studies in mice have successfully tested the injection of a virus carrying the normal gene for RPE65, and, separately, oral administration of a vitamin A-like compound.

In the current paper, Palczewski (formerly of the University of Washington) examined the effect of combining the two treatments in blind mice that did not have the LRAT enzyme. They report that gene therapy carrying the LRAT gene significantly restored electroretinographic (ERG) responses and pupillary light responses. Pharmacological intervention with orally administered drugs also caused long-lasting restoration of retinal function in LRAT-deficient mice and increased ERG response.

They noted that the oral treatment was easier to administer compared with injecting the gene therapy directly into the eye, but a disadvantage of the oral treatment was a potential for long-term systemic toxicity compared with the gene therapy. However, toxicological data gathered in this and previous studies have suggested no long term ill effects in mice.

It is possible that each treatment might eventually prove to be more suitable for a specific age group of patients, and therefore, combining the therapies might offer more effective treatment for a wider age range of patients, suggest the authors.

The team hopes that if the treatments are used together, treatment with oral retinoids could begin in infancy to avoid early sight loss and the difficulties associated with surgery in very young patients. And when patients are older, long-lasting drug-free treatment could be done by surgically introducing gene therapy. This study marks the first step in finding out whether these treatments will work effectively and safely in humans.
 

- PLoS Medicine
 

Case Western Reserve University

 
Subscribe to Retina Newsletter
E-mail Address:

 



Related Retina News

Master Proteins Dictate Retinal Differentiation Timetable
Yellow plant pigments lutein and zeaxanthin reduce risk of age-related macular degeneration
Objective way to diagnose diseases of colour perception
Antioxidants may slow retinal degeneration
Hormone Therapy Does Not Affect Age-Related Vision Loss
Eating Fish Protects Against Macular Degeneration
Research Highlights Risk Factors For Age-Related Vision Loss
FDA approves ranibizumab for the treatment of wet age-related macular degeneration
High Body Mass Index Increase the Genetic Risk of AMD
Ranibizumab Approved for Wet Age-Related Macular Degeneration


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

 

© Copyright 2004 onwards by RxPG Medical Solutions Private Limited
Contact Us