The leading cause of vision loss among older adults is age-related macular degeneration.
Affecting the central vision of the eye, around 200 million people worldwide suffer from it and this number is expected to rise to 288 million by 2040 as the population ages.
There are currently no effective treatments, but a study led by University College London researchers may have an answer. People suffering from AMD often start with blurred eyesight, or seeing a black dot in their central vision, which can expand to the point where there is no useful central vision left.
The exact cause is complex and thought to involve a combination of ageing, genetics, environment and lifestyle factors such as diet, weight, exercise, smoking and drinking alcohol. The risk of developing it significantly increases with age, and it primarily affects people over the age of 50, making tasks such as reading and driving difficult.
But the study, from the international team based in the UK, US, Germany and Australia, has found that increasing the levels of a key immune-regulating protein called IRAK-M in the cells at the back of the eye could help protect against it. The protein is crucial for protecting a layer of cells essential for maintaining a healthy retina, the retinal pigment epithelium (RPE).
When RPE cells are damaged, the result is serious eye conditions and vision loss. In this study of AMD, researchers studied the levels of IRAK-M in patient samples and mouse models. They found low levels in mice that lacked a gene – the IRAK3.
This gene is responsible for “switching on” the manufacture of the IRAK-M protein. What the researchers noted was IRAK-M decreases with age and that this decline is more pronounced in people with age-related macular degeneration. The team then showed that increasing IRAK-M levels helps protect against the effects of ageing and oxidative stress, and reduces retinal damage.
Co-lead author, Professor Andrew Dick of Bristol University, said their findings suggest boosting IRAK-M “could be a potential treatment strategy for AMD and could offer an exciting new therapeutic target for this common condition for which effective therapies remain elusive”.
So this breakthrough could lead to new and more effective AMD treatments. Scientists aim to help develop their therapies further through a new Bristol University spin-off company called Cirrus Therapeutics.
It’s good to see universities benefitting financially from their brilliant discoveries.