Science Current Events | Science News | Brightsurf.com
 

Bacterium present in eyes with 'wet' age-related macular degeneration

November 08, 2005
BOSTON - Researchers at the Massachusetts Eye and Ear Infirmary (MEEI) have found that Chlamydia pneumoniae, a bacterium linked to heart disease and capable of causing chronic inflammation, was present in the diseased eye tissue of five out of nine people with neovascular, or "wet," age-related macular degeneration (AMD). However, it was not found in the eyes of more than 20 individuals without AMD, providing more evidence that this disease may be caused by inflammation. The study is described in the November issue of Graefe's Archive for Clinical and Experimental Ophthalmology.

AMD is the leading cause of blindness in Americans over the age of 55. The majority of vision loss is due to neovascular AMD, the advanced form of the disease characterized by the formation of blood vessels in the macula, the center part of the eye's retina. These blood vessels often leak, thus giving neovascular AMD the name of "wet" AMD.

Researchers at the MEEI and Harvard Medical School (HMS) examined nine wet AMD membranes for the presence of C. pneumoniae and also determined whether this pathogen can change the function of eye cells in ways that can cause wet AMD. They found C. pneumoniae in the eyes of five out of the nine patients with wet AMD. They also tested tissue from more than 20 people who did not have AMD and did not find C. pneumoniae in any of these normal eye tissues.

"The paper showed that C. pneumoniae is capable of modifying the function of important cell types involved in regulating normal eye function," said lead author Murat Kalayoglu, MD, PhD. "We found that C. pneumoniae infection led to increased production of vascular endothelial growth factor (VEGF), the key protein involved in wet AMD. That C. pneumoniae infection of human eye cell types increases VEGF production is therefore significant and could explain in part why VEGF levels are increased in many people with wet AMD." Kalayoglu is an HMS research fellow in ophthalmology at MEEI.

Most of the new medications either marketed or being developed to treat wet AMD, such as Macugen (EyeTech Pharmaceuticals) and Lucentis (Genetech) block VEGF.

The study comes at a time of great interest in inflammatory mediators of AMD. Over the past seven months, a flurry of high-impact papers have shown, in aggregate, that nearly 50 percent of AMD can be explained by variations in a gene called Complement Factor H (CFH). This gene makes a protein that regulates the immune and inflammatory responses of the body.

"Our hypothesis is that C. pneumoniae may be the key link between CFH and AMD," Kalayoglu said. "That is, patients with CFH variations may be particularly susceptible to the damaging effects of chronic infection, and an infectious organism like C. pneumoniae may be particularly effective in accelerating inflammation and driving progression of AMD in these patients."

Kalayoglu and colleagues are currently collaborating with CFH researchers to study this hypothesis. "It may be possible to stop or reverse progression of AMD by identifying susceptible patients by diagnostic testing, and then treating these susceptible patients. Although C. pneumoniae is a bacterium that might respond to some antibiotics, much more work needs to be done before considering antibiotic therapy for AMD," he said.

"This is an important study suggesting that infection with C. pneumoniae may be a critical link between a genetic predisposition to AMD and actual progression to disease," said Gerald I. Byrne, Ph.D., professor and chairman of the Department of Molecular Sciences University of Tennessee Health Sciences Center. "This is yet another example of how an infection may unexpectedly contribute to a chronic disease. Certainly the association of C. pneumoniae with heart disease sets the stage for this pathogen's involvement in other chronic conditions. This work is, in some ways, reminiscent of studies done more than 15 years ago on infections and ulcers. Those studies were viewed with skepticism, but Drs. Marshal and Warren, the researchers who pioneered that work received the Nobel Prize this year."

The Graefe's paper builds on data from the same group that showed, for the first time, that an infectious agent is associated with AMD by epidemiological studies (Archives of Ophthalmology, April 2003).

Harvard Medical School


Related Macular Degeneration Current Events and Macular Degeneration News Articles


Study suggests new way of preventing diabetes-associated blindness
Reporting on their study with lab-grown human cells, researchers at The Johns Hopkins University and the University of Maryland say that blocking a second blood vessel growth protein, along with one that is already well-known, could offer a new way to treat and prevent a blinding eye disease caused by diabetes.

Complex signaling between blood and stem cells controls regeneration in fly gut
Having a healthy gut may well depend on maintaining a complex signaling dance between immune cells and the stem cells that line the intestine.

Patients with AIDS at increased risk of developing age-related macular degeneration
Patients with acquired immunodeficiency syndrome (AIDS) have a four-fold increase in their risk of developing intermediate-stage age-related macular degeneration (AMD) compared to people of the same age who are not infected with HIV.

First embryonic stem cell therapy safety trial in Asian patients
A clinical trial in the Republic of Korea for patients with degenerative eye diseases is the first to test the safety of an embryonic stem cell therapy for people of Asian descent.

Pharmaceutical industry regulation undermines NICE drugs appraisal work
Government policies that support UK pharmaceutical science and enhance export income are costing the NHS millions and undermine the National Institute for Health and Care Excellence.

TSRI study: Nerve cells and blood vessels in eye 'talk' to prevent disease
A new study from scientists at The Scripps Research Institute (TSRI) shows that nerve cells and blood vessels in the eye constantly "talk" to each other to maintain healthy blood flow and prevent disease.

Scientists X-ray anti-inflammatory drug candidates
Using DESY's ultra bright X-ray source PETRA III, scientists have decoded the molecular and three-dimensional structure of two promising drug candidates from the new group of Spiegelmers for the first time.

Study shows new technology may improve management of leading causes of blindness
Research published today in the Proceedings of the National Academy of Sciences (PNAS) demonstrates that technology invented by researchers at Oregon Health & Science University's Casey Eye Institute can improve the clinical management of the leading causes of blindness.

Caring for blindness: A new protein in sight?
Vasoproliferative ocular diseases are responsible for sight loss in millions of people in the industrialised countries. Many patients do not currently respond to the treatment offered, which targets a specific factor, VEGF.

Stem cell injection may soon reverse vision loss due to age-related macular degeneration
An injection of stem cells into the eye may soon slow or reverse the effects of early-stage age-related macular degeneration, according to new research from scientists at Cedars-Sinai.
More Macular Degeneration Current Events and Macular Degeneration News Articles

Macular Degeneration: The Complete Guide to Saving and Maximizing Your Sight

Macular Degeneration: The Complete Guide to Saving and Maximizing Your Sight
by Lylas G. Mogk (Author), Marja Mogk (Author)


The acclaimed book on macular degeneration—now completely revised and updated with cutting edge research and the latest developments in the field.

More than fifteen million Americans have age-related macular degeneration (AMD), and the disease will strike 200,000 more people this year. It is the most prevalent cause of vision loss in the western world. Dr. Lylas Mogk, the founding director of the Visual Rehabilitation and Research Center of the Henry Ford Health System, has a unique professional and personal understanding of AMD. A doctor and loving daughter of a parent with this frightening though manageable condition, Mogk here explains exactly what it is and how to limit its effect on your life. Reassuring and comprehensive—complete with illuminating first person stories of...

Overcoming Macular Degeneration: A Guide to Seeing Beyond the Clouds

Overcoming Macular Degeneration: A Guide to Seeing Beyond the Clouds
by J.D. Solomon (Contributor)


Each year, more than 400,000 Americans are diagnosed with macular degeneration, an age-related, progressive eye disease that immediately raises a fear of total blindness. The good news is: YOU ARE NOT GOING BLIND. However, you are dealing with a disease that causes serious visual impairment—an inconvenience the author, Dr. Yale Solomon, is personally familiar with because he has macular degeneration. Now this respected ophthalmologist offers a compassionate and understanding look at both the medical and human side of macular degeneration and ways to meet the challenge of its impact on everyday life. This newly updated edition includes a comprehensive appendix of associations, organizations and foundations, large-print publishers, audio and video resources, and a helpful list of...

Eat Right for Your Sight: Simple, Tasty Recipes that Help Reduce the Risk of Vision Loss from Macular Degeneration

Eat Right for Your Sight: Simple, Tasty Recipes that Help Reduce the Risk of Vision Loss from Macular Degeneration
by Jennifer Trainer Thompson (Author), Johanna M. Seddon MD ScM (Author), The American Macular Degeneration Foundation (Draft Writer)


Safeguard your vision with 85 simple, satisfying recipes rich in the nutrients that fight macular degeneration

The Bad News: Age-related macular degeneration (AMD) is the leading cause of central vision loss in adults over the age of fifty. It can wreak havoc on the ability to see faces, read, drive, and move about safely. Millions of people are at risk, and we still don’t have a cure.

The Good News: The latest research suggests that healthy lifestyle choices, including a diet rich in lutein, zeaxanthin, and other key nutrients, can delay the onset and progress of AMD. Eat Right for Your Sight provides a delicious way to add the best ingredients for eye health to every meal of the day. Feast your eyes on these appealing recipes:Sweet Pea GuacamoleChicken-Vegetable...

Macular Degeneration... ...Macular Regeneration (Natural Vision & Eye Care) (Volume 3)

Macular Degeneration... ...Macular Regeneration (Natural Vision & Eye Care) (Volume 3)
by Dr. Glen Swartwout (Author)


When asked, the one thing most people would least want to lose is their vision. Macular Degeneration is particularly frustrating, because it affects the central vision, so that whatever you look at is distorted or even disappears in a black hole... While recent announcements in the news have brought hope to millions that stem cell injections deep into the eye have now been observed to stimulate regeneration of the macula, potentially restoring functional vision to those blinded by this common condition, the methods outlined in detail in this book have stimulated this kind of healing as well, without any invasive procedures. Such results have been observed independently by two different Harvard trained retinal specialists following Dr. Swartwout's patients after they chose to pursue...

The First Year: Age-Related Macular Degeneration: An Essential Guide for the Newly Diagnosed

The First Year: Age-Related Macular Degeneration: An Essential Guide for the Newly Diagnosed
by Daniel L. Roberts (Author)


Age-related macular degeneration (AMD) is a progressive disease of the retina wherein the light-sensing cells in the central area of vision (the macula) stop working and eventually die. AMD is the leading cause of legal blindness in people over 50. From the moment of his own diagnosis, educator and musician Dan Roberts has made it his mission to provide the most up-to-date information about AMD, its effects and challenges, through his website at mdsupport.org. Receiving over 60,000 unique visitors monthly, MD Support is the go-to for all things AMD. Now, as a "patient-expert," Roberts applies his wealth of knowledge to the First Year series, providing crucial information for the newly diagnosed, including cutting edge therapies, and tips on how to navigate everyday tasks with diminishing...

Macular Disease: Practical Strategies for Living with Vision Loss

Macular Disease: Practical Strategies for Living with Vision Loss
by Peggy R. Wolfe (Author)


Filled with compiling ideas for living well with vision loss from macular disease, this book's positive, take-charge approach provides encouragement to both the newly diagnosed and those at later stages of their disease by showing ways to compensate for their declining sight. Featuring photos of special lighting and other aids and insight from the author's own personal experience with low vision, this oversized handbook is ideally formatted for readers with vision loss by employing the use of large print on glare-resistant paper. Offering reassurance, hope, and personal insight, this revised edition is filled with descriptions of adaptive strategies and assistive technologies. With strong endorsements from medical communities, the book includes an invaluable index and resource list for...

Macular Degeneration: From Diagnosis to Treatment

Macular Degeneration: From Diagnosis to Treatment
by David S. Boyer MD (Author), Homayoun Tabandeh MD (Author)


With a focus on giving those diagnosed with macular degeneration the necessary information to make sound treatment choices, this reference aims to answer patients’ questions and ease their anxiety. The book provides information on the symptoms, causes, and emotional impact of macular degeneration; how the disease is diagnosed; choosing the right physician; and how to adapt the home and workplace to be “eye friendly.” In addition, it outlines the newest treatment options, drugs and surgical techniques, ways to slow the progression of the disease, and the importance of nutrition and general fitness on eye health. Written by two doctors with decades of experience treating thousands of patients, it supplies essential facts while affirming that people living with the disease can still...

Stem Cells Heal Your Eyes: Prevent and Help: Macular Degeneration, Retinitis Pigmentosa, Stargardt, Retinal Distrophy, and Retinopathy.

Stem Cells Heal Your Eyes: Prevent and Help: Macular Degeneration, Retinitis Pigmentosa, Stargardt, Retinal Distrophy, and Retinopathy.
by Carlyle Coash MA (Author), Adam Miller (Author), Damon P Miller II MD (Author)


A physician and pioneer in the integrative treatment of serious eye diseases such as Macular Degeneration, Retinitis Pigmentosa, Stargardt and other retinopathies reveals the best strategies used today to prevent and reverse these devastating diseases. Drawing on some of the hottest topics in modern medicine, the book discusses the surprising revelations from the research in Epigenetics and adult stem cells. Your genes are not your destiny. From our work with thousands of people, we understand that you might be fearful that you will lose your independence or your ability to do even the simplest tasks because serious eye disease is taking your sight. This book empowers you with simple tools that combat degenerative eye disease. Tools that support a healthy lifestyle and methods to remove...

Macular Degeneration: A Complete Guide for Patients and Their Families

Macular Degeneration: A Complete Guide for Patients and Their Families
by Michael A. Samuel (Author)


For people who start losing their vision to macular degeneration, the prospect of impending blindness is frightening and terribly depressing. They often get contradictory advice about surgery, medical treatments, natural supplements, and lifestyle changes that might arrest or reverse the condition, and these conflicting recommendations only compound their anxiety.

Finally, in Macular Degeneration: A Complete Guide for Patients and Their Families, patients and their loved ones can turn to one easy-to-understand and authoritative source for up-to-date information about macular degeneration. Written by renowned ophthalmologist Michael Samuel, M.D., a retinal specialist, this book casts the spotlight on macular degeneration and dispels the myths surrounding this disease.

Macular...

Healing the Eye the Natural Way

Healing the Eye the Natural Way
by Edward C. Kondrot MD (Author), William K. Coors (Author)


Alternative Medicine and Macular Degeneration; A 12 step guide to improve your vision. Featuring information on vitamin and nutritional terapy, homeopathy, mico-current stimulation and chelation tgerapy. Written by a homeopath and ophthalmologist to include a most comprehensive approach to treating Macular Degeneration, a condition that is still considered hopeless by conventional medicine. The clear approach and patient testimonials will inspire patients and doctors alike to take a new look at the condition most responsible for blindness in the over 60 age group.

© 2015 BrightSurf.com