SEATTLE — The world’s leading cause of blindness may be treatable thanks to a new form of omega-3 fish oil. Scientists have created a type of the omega-3 fat DHA (docosahexaenoic acid) which protects the eyes. The supplement can cross into the retina from the bloodstream, unlike similar versions of the supplements already available on store shelves.
It could halt age-related macular degeneration (AMD) that afflicts one in 10 Americans over the age of 50. Researchers believe this supplement may also stop visual decline in patients with diabetes and dementia. Experiments in mice found LPC (lysophospholipid)-DHA reduced Alzheimer’s-like eye problems.
“Dietary LPC-DHA is enormously superior to TAG-DHA in enriching retinal DHA and could be potentially beneficial for various retinopathies in patients,” says Sugasini Dhavamani, a research assistant professor in the Department of Medicine at the University of Illinois at Chicago, in a media release.
“This approach provides a novel therapeutic approach for the prevention or mitigation of retinal dysfunction associated with Alzheimer’s disease and diabetes.”
Mice taking the new DHA experienced nearly 100% improvement
The retina is a small area of tissue at the back of the eye containing light sensitive cells, which DHA helps to maintain. However, the retina can suffer damage due to reduced blood flow — a hallmark of both diabetes and dementia.
The breakthrough has implications for people with AMD, Alzheimer’s disease, diabetes, and retinitis pigmentosa, the study authors say.
“Increasing the retinal DHA at clinically feasible doses has not been possible until now because of the specificity of the blood–retinal barrier that is incompatible with the specificity of the intestinal barrier,” Dr. Dhavamani explains. “This study uses the novel approach of dietary LPC-DHA that overcomes both intestinal and blood–retinal barriers and improves retinal function.”
Study authors tested the fish oil on mice bred to exhibit processes similar to those found among people with early-onset Alzheimer’s. After six months, amounts of retinal DHA in those fed LPC-DHA daily showed a 96-percent improvement. The supplements successfully preserved the structure and function of the retina.
In contrast, current supplements had no effect on levels or efficiency. The results suggest LPC-DHA supplements will help prevent many types of vision impairment.
Researchers used dosages equivalent to about 250 to 500 milligrams of omega-3 fatty acids per day in humans. Further safety studies will be necessary before human trials can begin. Dr. Dhavamani presented the findings at a meeting of the American Society for Biochemistry and Molecular Biology in Seattle.
South West News Service writer Mark Waghorn contributed to this report.