Age-related macular degeneration:

Age-related macular degeneration: the promise of treatment based on stem cells

The first cause of visual impairment among those over age 50, macular degeneration related to age (AMD) is a disease of the central region of the retina called the macula

It begins with a phase most often without clinical signs, known as age-related macular degeneration, or AMD, a debutante, which will evolve over several years to the AMD intermediate stage at which appear a visual impairment and deposits visible by examining the back of the eye.

At the ultimate stage, AMD advanced is characterized by atrophy, with loss of photoreceptors and cells of the underlying called the pigmented epithelium (“AMD atrophic”), or by the appearance of a macular edema (“wet AMD”).

“Without that one can predict at an early stage of what will be the form of AMD advanced who will show up, half will evolve to form atrophic and the other half to the wet form,” says professor Michael Weber, ophthalmologist in the teaching hospital of Nantes. The two forms lead, without treatment, to irreversible degradation of the macula and loss of central vision. “A quarter of octogenarians suffer from age-related macular degeneration, and 10 to 15 % of AMD,” professor Jean-François Korobelnik, ophthalmologist at the university hospital of Bordeaux.

How many people are affected? All forms combined, this disease affects approximately 1.5 million French.

“But its frequency increases with age.

A quarter of octogenarians suffer from age-related macular degeneration, and 10 to 15 % of AMD,” says professor Jean-François Korobelnik, ophthalmologist at the university hospital of Bordeaux. For the past ten years, the wet form, which progresses more rapidly, is an effective treatment consisting of injections directly into the eye (injections, intra-vitréennes). Today, it is the form atrophic, of course is more slow, but inevitable, who finds himself an orphan of treatment. The lampalizumab, only medication arrived in the final phase of clinical trials, has not shown to decrease the atrophy compared to placebo. One of the clinical trials conducted by Roche has been arrested in last September. Other drugs are still in the process of development against age-related macular degeneration atrophic, but in early stages of clinical trials earlier.

At the same time, the researchers are focused on cellular therapy, which uses embryonic stem cells, capable of differentiating into all cell types of the body.

Two preliminary clinical trials of this new type of therapy have been presented at the conference of the american Academy of ophthalmology in mid-November in New Orleans. They suggest a promising lead.

Both of these tests involve grafts of epithelial cells retinal pigment which have an important role in the proper functioning of the photoreceptors.

The researchers have speculated that AMD atrophic corresponds to the gradual disappearance of the cells of the retinal pigment epithelium (RPE) and the photoreceptors located at the level of the macula. In the restaurant the retinal pigment epithelium, they hope to be able to save the photoreceptors. “At the stage of age-related macular degeneration food supplements containing vitamins and lutein reduce by 25% the evolution towards a form of advanced” professor Jean-François Korobelnik “It is a strategy which, if it demonstrates its effectiveness, could be interesting at an early stage of the disease, before the photoreceptors are reached,” professor Michel Weber. But the way to go before getting to that point is still fraught with difficulty since, at this stage, there is no evidence that a pigmented epithelium regenerated would stop the progression of the disease. While waiting for the arrival of therapeutic solutions that are really effective, the only weapon available to combat AMD, atrophic is prevention.

First measure advocated by the specialists of the view: smoking cessation. The risk of AMD is in effect multiplied by 2. .5 for those smoking more than 20 cigarettes per day. This excess risk persists for up to 20 years after smoking cessation. At the early stage of the disease, taking dietary supplements would help prevent its aggravation.

“At the stage of age-related macular degeneration food supplements containing vitamins and lutein reduce by 25% the evolution to an advanced form,” explains professor Jean-François Korobelnik. Only downside, if these nutrients have shown to be effective, these are not drugs, and they are not supported by social Security. “Take these supplements cost around 20 euros per month, for a profit, which is not visible immediately as it reduces a risk to come.

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Result: many patients drop out,” says professor Jean-François Korobelnik. . .

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