Injectable omega-3 halts progression of dangerous arterial plaques
Researchers have developed an injectable form of DHA, an omega-3 fatty acid, that is effective in halting the progression of the arterial fatty plaques that can lead to heart attack and stroke. The novel treatment may one day be used to treat heart disease.
DHA (docosahexaenoic acid) is an omega-3 polyunsaturated fatty acid that’s long been promoted for its anti-inflammatory and antioxidant effects, which are thought to help prevent atherosclerosis or the build-up of fatty plaques on artery walls, a major cause of heart attacks and strokes. While it’s found in oily fish like salmon, DHA is usually taken as an oral supplement. The problem is that it’s poorly absorbed by the gut when taken in that form, making it difficult to take advantage of its health effects.
Researchers from the National University of Singapore developed an injectable form of DHA that better exploits DHA's therapeutic potential, finding that it’s effective at targeting atherosclerosis and may be a novel treatment for heart disease.
They wrapped DHA in a liposomal formulation to protect it against degradation and increase its concentration in the tissues. Liposomes are tiny, artificially created spherical sacs that can be created from cholesterol and natural, non-toxic phospholipids, and are used to carry drugs or other substances into the tissues.
To test the therapeutic efficacy of their novel treatment in atherosclerosis, the researchers fed mice a high-fat diet for four weeks to establish arterial plaques, followed by eight weeks of intravenous administration of control liposomes or DHA liposomes while continuing the high-fat diet.
The researchers observed that when delivered into the bloodstream, the DHA liposomes accumulated in the arterial plaques. The liposomes were absorbed by macrophages, a type of white blood cell, which reduced the plaques. In addition, the plaque was more stable, making it less likely to rupture and cause an arterial blockage and subsequent heart attack or stroke.
The study's results suggest that injectable DHA is a promising new way of halting the progression of atherosclerosis, the researchers say. They are looking ahead to human clinical trials.
“This is the first study to demonstrate that injectable nanoformulation can remarkably improve the therapeutic effects of DHA against atherosclerosis at a dose of 40,000 to 400,000 times lower than the reported usage of oral DHA,” said Jiong-Wei Wang, corresponding author of the study. “We are optimistic about the clinical benefits it may bring to our patients, and are exploring clinical trials on patients in the near future.”
The study was published in the Journal of Controlled Release.