Apolipoprotein E (apoE) is a protein component that helps transport cholesterol in the blood between the liver and other tissues, says Steven Fliesler, Ph.D., professor and director of research in the department of ophthalmology at Saint Louis University School of Medicine and lead investigator. It also is present in the brain and other nervous tissues, including the retina.
There are three genetically determined forms of apoE (apoE-2, apoE-3 and apoE-4), each encoded by a specific sequence of DNA . Studies suggest that apoE-3 may play a protective role in the nervous system, assisting in the repair of nervous tissue, such as after a brain injury.
On the other hand, people who have elevated levels of the apoE-4 version of the protein are at an increased risk for developing the late onset, familial type of Alzheimer’s disease.
The mystery SLU researchers are now trying to solve is why the reverse seems to be true when it comes to advanced macular degeneration.
“Paradoxically, the exact opposite trend seems to prevail,” Fliesler says. “ApoE-4 seems to correlate with a reduced incidence of macular degeneration.”
For the next two years, Fliesler and his team will test whether the presence of one or the other form of apoE slows down, quickens, or does essentially nothing to the rate of retinal degeneration in genetically altered mice that undergo progressive, age-dependent vision loss. Fliesler’s team will selectively introduce either the human apoE-3 or apoE-4 gene into the mice and then study what effects this may have on the structure and function of their retinas.
“We hope our experiments with transgenic mice will provide some clues as to what apoE is doing in the retina and why one form of apoE versus another would predispose someone to having macular degeneration,” Fliesler says. “At this point, it makes no sense to me that the same molecule would have very different actions in the brain versus the retina, both of which are nervous tissue,” he says.
Macular degeneration, which affects nearly 12 million people in the United States - about one in four older adults – and about 50 million worldwide, is caused by the deterioration of the central portion of the retina, known as the macula. The macula is responsible for focusing central vision in the eye, and it controls the ability to read, drive a car, recognize faces or colors and see objects in fine detail.
As people age, their chances for developing eye diseases increase dramatically. Smoking is also a strong risk factor, as it seems to be for other age-related diseases.
As the baby boomers get older and the average human lifespan continues to increase, these diseases will have an increasingly significant impact on society, including quality of life for the elderly as well as worldwide escalating healthcare costs, says Fliesler.
Established in 1836, Saint Louis University School of Medicine has the distinction of awarding the first M.D. degree west of the Mississippi River. Saint Louis University School of Medicine is a pioneer in geriatric medicine, organ transplantation, chronic disease prevention, cardiovascular disease, neurosciences and vaccine research, among others. The School of Medicine trains physicians and biomedical scientists, conducts medical research, and provides health services on a local, national and international level.
Rachel Otto | EurekAlert!
New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)
Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
27.04.2017 | Life Sciences
27.04.2017 | Physics and Astronomy
27.04.2017 | Earth Sciences