Macular Degeneration and your eyesight

You have most probably heard of this very common condition that damages your eyesight as you age. Because this condition affects more elderly people it is often referred to as age-related macular degeneration. Unfortunately there is no cure available for this condition however there are treatments that can help. This blog outlines the latest in research and treatments regarding macular degeneration and aims to help you make the most out of your eyesight in the mean time.

Now macular degeneration as the name implies affects the macula, which is an area right at the back of the eye on a structure that detects light known as the retina. Your macula is the part of the retina that allows you to see things in great detail. In fact many birds have better maculas than us, as they need to see things in great detail from up in the air. The condition of macula degeneration implies that the macula is damaged and as this damage becomes more extensive your eyesight will be affected. There are two types of macula degeneration and they are known as the wet or the dry type, the most common of the two is ‘dry’ maculae degeneration. In this type you get little yellow patches that pop up around your macula and your vision slowly worsens. In ‘wet’ macula degeneration there are tiny blood vessels in the back of your eye that grow and then leak out blood and other fluid. This tends to make ones vision worse more quickly and you should note that dry degeneration can turn into the wet kind.

Those who present with this condition for the most part have difficulty reading, making out fine detail and even have trouble recognizing friends and families faces. After a few years of having this condition things that are in the middle of your vision will begin to look blurred and you may struggle to make things out. After a while the middle of your vision may just appear black and you often cant see anything in this area, this means that you will be unable to see things that are right in front of you. However your peripheral vision will not be affected.

There are things that you can do to cope with this condition as well as medicines that can help. Your doctor may teach you how to make better use of your peripheral vision and tell you that using bright lighting in your home will help you see better. You may also need to make text on the computer screen bigger and use magnifying glasses when reading a book. Most of the medical treatments are aimed at the treatment of wet macular degeneration and in fact there are not many effective treatments for the dry variety. Laser therapy can be used to stop the macular degeneration from getting worse in the sense that these lasers burn away those yellow patches that form around the macular early in the disease course. Also there is no need to worry as laser therapy is not painful and is quite quick, however the evidence supporting this form of treatment is not great at this stage. In fact some research suggests that laser treatment can cause new blood vessels to from on the back of the eye that can make your sight worse.

Mineral and vitamin supplements may be useful in slowing down or stopping macula degeneration from occurring. You should take zinc, vitamin E and C as well as beta-carotene. Remember here that you will need to take them for a long time and in high doses to be affective and remember that these are not without their side effects. Some people find that they have problems with passing urine, others complain of stomach pains and some people notice that their skin turns a little yellow. If this is that case with you then you should stop taking the tablets and visit your doctor.

Wet macular degeneration can be treated with photodynamic laser surgery whereby a dye that is sensitive to light is injected into your bloodstream and then a laser is shone into your eye. The dye that was injected into the blood helps the laser to destroy all of those leaky blood vessels that are damaging your eye. This method has mixed reviews on effectiveness and one should have a good discussion with their doctor regarding the risks and benefits of this procedure before having it done.

There is another type of laser that can be used to destroy the blood vessels in the eye that leak, but this is only affective in a few people with very severe disease. There is a chance with this procedure that the blood vessels will grow back anyway and the laser can sometimes damage the eye. Radiotherapy is another option but lacks suitable research to say whether or not it works and we always worry that radiation may damage other parts of the eye.

There is an injection that you can have in your eyeball called pegaptanib, however for obvious reasons not many people like the idea of this if they can help it. Also you have to have two injections every month and the evidence is not great that it works wonders, although there are some convincing studies. There is another injection called ranibizumab that you get in your eyeball and this also does not have great results but is indicated in people with wet macular degeneration that is getting worse.

So the most important thing is what will happen to you and in this case the outcome is not fantastic. Over many years your vision will gradually get worse and it will be much worse in the centre of your vision than in the peripheries and you are unlikely to go completely blind. Unfortunately we don’t know how quickly things will turn bad and each patient is different, but most people manage to get around even with severe disease as they are able to use their peripheral vision much more effectively.

FDA grants pSivida, Alimera expedited review for macular degeneration therapy

FDA grants pSivida, Alimera expedited review for macular degeneration therapy
August 31, 2010 by MassDevice staff

pSivida Corp. and Alimera Sciences win priority review status for their Iluvien drug/device combination, designed to treat diabetic macular degeneration.
PSDV, ALIM logos

The Food & Drug Administration put pSivida Corp. (NSDQ:PSDV) and Alimera Sciences Inc. (NSDQ:ALIM) on the fast track, granting an expedited review for their drug/device combination designed to treat diabetic macular edema.

Watertown, Mass.-based pSivida and Alpharetta, Ga.-based Alimera filed a new drug application with the FDA in June for Iluvien, a sustained release drug delivery system that delivers flucocinolone acetonide, a steroid, for the treatment of DME.

The federal watchdog agency granted priority review status to the application, moving the goal for finishing the review from 10 months back to six months.

That means a response could drop during the fourth quarter, pSivida president and CEO Dr. Paul Ashton said in prepared remarks, adding that FDA approval would trigger a $25 million milestone payment from Alimera.

The milestone payment wouldn't be the first time Alimera ponied up for pSivida. Its $72 million IPO in April triggered the repayment of a $15 million loan and $225,000 in interest. The companies are seeking European approval for Iluvien. If it makes it to market, pSivida will collect 20 percent of the net profits.

The FDA has already cleared a pair of pSivida products: Retisert, for the treatment of posterior uveitis, and Vitrasert for the treatment of AIDS-related cytomegalovirus retinitis. Both are licensed to Bausch & Lomb Inc. The company is also developing other ophthalmic products with Pfizer Inc. (NYSE:PFE), its largest shareholder, and has products of its own in the pipeline outside of ophthalmology, according to a press release.

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Gene therapy can correct inherited retinal eye diseases

Researchers at the American Academy of Ophthalmology have found that Leber’s congenital Amaurosis (LCA), a very severe form of retinal disease
can be improved with the help of gene therapy.

Not only that, but the improvements were also found to be stable for two years.

Gene Therapy Can Correct Retinal Eye Diseases: LCA can be diagnosed in children at a very early age, sometimes even at infancy.

The main symptoms
of LCA are severity in vision loss and nystagmus(involuntary eye movement). By the time a person reaches his thirties or forties LCA develops into blindness.

* The impact of gene therapy could mainly be observed in children. The visual acuity and light sensitivity was tremendous in these children.
* Not only in children, researchers were also able to observe improvement in adults.

The Research and Theory: LCA is due to the mutations caused in any of the 13 genes in our body. Researchers were studying a Type 2 LCA which is due to mutation in the RPE65 gene.

* The doctors injected a normal functioning RPE65 gene which was joined with a virus into the sub-retinal space upon performing a surgery.
* The altered virus places the normally functioning RPE65 gene into the diseased cells and modifies the defective enzymes.
* After 2 weeks from the date of surgery, doctors observed that the patients reported an improvement in vision even in dim light.
* There were a few patients who also said that their visual acuity improved.
* A few even experienced massive improvement in nystagmus.
* The most encouraging result was that none of the patients experienced adverse effects.

Gene therapy does not improve sight on a permanent basis. But, gene therapy can correct inherited retinal eye diseases and help people restore sight.

People who undergo gene therapy need not be classified as blind any more. Researchers are trying hard to implement this technique in a safer way in younger children.

Drug Research could lead to AMD therapy

By Adrian Galbreth

New drug research may pave the way for more effective treatments of age-related macular degeneration - the leading cause of blindness in the western world.

Those are the claims being made by researchers at Tufts University School of Medicine, who say that a protein known as galectin-3 promotes the growth of new blood vessels, and that targeting the protein can "significantly reduce" angiogenesis.

The findings have been published in the Journal of Experimental Medicine and may lead to treatments for diseases caused by excessive angiogenesis, which include AMD, said Dr Noorjahan Panjwani, who led the project.

She explained: "Our study shows that galectin-3 protein binds to glycans of specific cell-adhesion proteins to activate the signaling pathways that bring about angiogenesis. This improved understanding may provide a more targeted approach to preventing harmful angiogenesis."

Meanwhile, another team of researchers at Tufts have found that that non-viral gene therapy can delay the onset of some forms of eye disease and offer hope to retinal degeneration sufferers.ADNFCR-1853-ID-800028486-ADNFCR

Visudyne therapy

Age-related macular degeneration (AMD) is a progressive disease of the eye, meaning that it can’t be cured. The good news is that AMD can be controlled. Treatments available today can slow the vision loss associated with AMD and even restore some vision.

Wet and dry age-related macular degeneration (AMD) differ in several important respects, including treatment options. The only way to find out which AMD treatment regimen or management plan is right for you is to talk to your ophthalmologist or retinal specialist.

Visudyne therapy treats a form of AMD called predominantly classic subfoveal CNV due to AMD.

In this form of AMD, abnormal blood vessels leak fluid and/or blood under the macula—the part of the eye responsible for central vision—causing serious vision loss. During therapy, Visudyne is injected into the patient (generally through the arm). Next, light from a low-energy laser activates Visudyne, causing it to destroy the leaky vessels. As a part of a wet AMD treatment regimen, Visudyne therapy may help slow its progression.

Ask your ophthalmologist or retinal specialist if Visudyne therapy may be right for you.

Other treatment options
Anti-VEGF (anti-vascular endothelial growth factor) treatments block the formation of new abnormal blood vessels

Medicine from Moss to produce human protien

Diabetics use human insulin produced in bacteria in order to treat their metabolic disorder. Many other genetically engineered proteins are also on the advance. They are being used for diagnosis as well as for therapy.

Whereas insulin used to be extracted from slaughterhouse waste, today it is produced genetically in bacteria. However, more complex proteins have to be synthesised in more complex organisms. This takes place mostly in bioreactors using animal cell lines. Biotechnologist Prof. Ralf Reski from Freiburg, Germany, has developed the moss Physcomitrella patens into a safe and inexpensive alternative supplier of medicine.

His group has now, under Dr. Eva Decker, for the first time succeeded in producing a human protein in a moss bioreactor, which has been assigned the "orphan drug" status by the respective EU authorities. This means the development and approval of such medication receive particular support from the authorities. In many people the amount of this protein decreases with old age - with severe consequences. Eva Decker explains: "With the complement factor H we have produced a protein in moss that otherwise occurs only in blood and is important for the immune system. Not enough of this protein in older people is the main cause of blindness for 50 million people worldwide. This age-related macular degeneration (AMD) is a problem, particularly in industrialised countries."

Biochemists from the Freiburg Centre for Systems Biology under Dr. Andreas Schlosser were able to show with the help of high-performance mass spectrometers that the human factor H engineered into and produced by moss was a complete protein. Infection biologists headed by Prof. Peter F. Zipfel from the Hans-Knöll-Institute in Jena, Germany, were able to prove in biological assays that factor H from moss is fully functional. "Currently factor H is not available in pharmacies, so treatment for AMD with this protein is not possible. To date recombinant production of factor H was barely feasible. I am convinced that for the first time the moss bioreactor is a promising option", says Peter Zipfel.

This work was supported by the German Federal Ministry of Education and Research (BMBF), the Freiburg Initiative for Systems Biology and the Cluster of Excellence BIOSS.
Dr. Annette Büttner-Mainik, first author of the publication, was a Kekulé scholarship holder from the endowment fund of the German Chemical Industry (FCI).
The title of the original publication is: Annette Büttner-Mainik, Juliana Parsons, Hanna Jérôme, Andrea Hartmann, Stephanie Lamer, Andreas Schaaf, Andreas Schlosser, Peter F. Zipfel, Ralf Reski, Eva L. Decker (2010): Production of biologically active recombinant human Factor H in Physcomitrella. Plant Biotechnology Journal, doi: 10.1111/j.1467-7652.2010.00552.x.

"It will take a while before medication produced in moss is available in pharmacies", says Ralf Reski, member of the Innovation Think Tank of the governor of Baden-Wuerttemberg. "We are further optimising the moss bioreactor using methods from Systems Biology and Synthetic Biology. However, the implementation of clinical studies and the setting up of industrial production is long-winded and expensive; this is the task of industry and not of university research."

Stem Cell Transplants Stalled Blindness in Rats

Researchers say putting nerve stem cells from StemCells Inc near the retinas of rats with a form of macular degeneration helped keep the disease from advancing to blindness for several months.Nerve stem cell transplants may help slow the progression of macular degeneration, the most common cause of blindness in the developed world, U.S. researchers said on Monday.


They said putting nerve stem cells from StemCells Inc near the retinas of rats with a form of macular degeneration helped keep the disease from advancing to blindness for several months.


"These cells improve the chemical environment in the back of the eye," said Ray Lund of the Casey Eye Institute at Oregon Health & Science University in Portland, whose findings were presented at the Society for Neuroscience meeting in Chicago.


Lund said the mechanism is not clear, but he suspects that when immature nerve cells are placed near the retina, they produce growth factors that protect the cells from damage by the disease.


"It's basically a chemical pump that is sitting in the right place and producing the right things," Lund said in a telephone interview.


Where normally animals with eye disease lost their vision by three months old, rats that got the transplants kept their vision for at least seven months, he said.


"There is no evidence that they (the transplanted cells) do any damage," Lund said, adding that the animals do not develop tumors, a key worry for stem cell transplants.


The findings raise hope for use of the treatment in humans with a range of diseases in which the retina become damaged, including age-related macular degeneration or AMD, which affects nearly 30 million people worldwide, including 15 million Americans.


People with AMD lose central vision when delicate light-sensing cells of the macula, a region at the center of the retina, become damaged.


In the rats, the researchers transplanted immature nerve cells into the space near the retina. Lund said the same could be done in people with retinal disease.


Dr. Stephen Huhn, head of the Central Nervous System research program at StemCells Inc, said the cells are adult neural stem cells. He said they are multipotent, meaning they can morph into different types of nerve cells.


The company has already tested the treatment in a study of six patients with Batten's disease, a fatal inherited disorder of the nervous system.


"Having a cell that has already entered clinical testing that has been well tolerated at very high doses in the brain gives us a lot of confidence about exploring the same type of strategy in the eye," Huhn said.


Huhn said he thinks the cells may be especially well suited for use in the retina, brain and spinal cord, which are less likely to reject the cells than other parts of the body.


Ultimately, he said the hope is to develop a treatment for the dry form of macular degeneration, which affects around 90 percent of patients diagnosed with AMD. No treatments are available for this form of the disease.


Huhn said treating this form of the disease may prevent some people from developing wet AMD, in which tiny new blood vessels grow between the retina and the back of the eye.


This form of the disease can be treated with modern drugs like Lucentis, from Novartis and Roche's Genentech, and Pfizer's Macugen.