Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

University of Utah study suggests cellular waste to blame for a form of blinding eye disease

24.11.2004


Discovery offers hope for a pharmaceutical intervention to treat some forms of retinitis pigmentosa



Gene mutations that impair the ability of photoreceptor cells to properly dispose of waste - and as a result cause the blinding eye disease retinitis pigmentosa - have been identified by vision researchers at the University of Utah’s Moran Eye Center. The discovery raises concerns that carbonic anhydrase inhibitors (medications often used to treat both heart and eye diseases) may adversely affect vision. The study is published in the November 24, 2004 online version of the journal Human Molecular Genetics.

Retinitis pigmentosa (RP) is one of the most common causes of blindness. It affects one in 3,500 people or approximately two million people worldwide. Patients with RP typically are diagnosed with night blindness and, as the disease progresses, they eventually lose all of their peripheral vision and a significant portion of their central vision.


Photoreceptor cells (known as rods and cones) are located in the eye’s retina and are responsible for converting light into electrical impulses for transmitting messages to the brain, according to Kang Zhang, M.D., Ph.D., the study’s senior author. This process of converting light to electrical signals in the retina requires a tremendous amount of energy which, in turn, creates waste in the form of carbon dioxide and bicarbonate.

According to the paper, patients in the study each had a mutation in which a defect in the process responsible for handling carbon dioxide waste and maintaining acid and base balance led to photoreceptor degeneration.

Zhang says the mutation inhibits function of a protein complex made up of carbonic anhydrase 4 (CA4) and Na+/Bicarbonate Co-transporter1 (NBC1) from doing its job of controlling acid and base balance. "In healthy eyes this acid waste is released from the retina and into the bloodstream via tiny blood vessels called the choriocapillaris which are located adjacent to the photoreceptors. When this doesn’t happen, we see the death of photoreceptor cells and the start of retinitis pigmentosa," said Zhang.

The study also suggests additional research is needed to determine whether carbonic anhydrase inhibitors may affect vision. According to the study, "the importance of a functional CA4 for survival of photoreceptors implies that carbonic anhydrase inhibitors, which are widely used as medications, particularly in the treatment of glaucoma, may have long-term adverse effects on vision."

Zhang says it’s not clear how many cases of RP can be attributed to this newly discovered CA4 gene mutation. "However, we have already gained invaluable lessons from studying four families with this mutation. The next step is to begin working on a pharmaceutical intervention to counteract the effect of the gene mutations," he said.

Although one of the three gene mutations in this study was independently reported by a group of researchers at the University of Cape Town and St. Louis University, Zhang says these new results indicate a completely different mechanism causing blindness.

In addition to Zhang, other investigators contributing to the new findings are from the University of Alberta, University College of London, Universitätsaugenklinik Tübingen, and University Medical Centre Nijmegen. Zhang is an assistant professor of ophthalmology and visual sciences at the Moran Eye Center. He is also an investigator for the Program in Human Molecular Biology and Genetics at the University of Utah’s Eccles Institute of Human Genetics.

Chris Nelson | EurekAlert!
Further information:
http://www.utah.edu
http://hmg.oupjournals.org

More articles from Life Sciences:

nachricht Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery
20.01.2017 | GSI Helmholtzzentrum für Schwerionenforschung GmbH

nachricht Seeking structure with metagenome sequences
20.01.2017 | DOE/Joint Genome Institute

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>