“Our findings support the proposed concept that DHA and docosanoids (molecules made in the brain at the onset of injury or disease) are responsible for activating sustained cellular mechanisms that elicit long-term preconditioning protection,” says Nicolas Bazan, MD, PhD, Boyd Professor and Director of LSU Health New Orleans Neuroscience Center of Excellence.
Fish oil contains two types of polyunsaturated fatty acids (PUFAs) -- omega-3 (docosahexaenoic acid or DHA) and omega-6 (arachidonic acid or AA). They have distinctly different actions. Omega-3 PUFAs and their enzymatic metabolic derivatives, docosanoids, display potent anti-inflammatory and pro-resolving properties in contrast to the pro-inflammatory actions of omega-6 PUFA derivatives. The researchers found that although they are released concomitantly, DHA can alter the action of AA. When they supplemented DHA prior to the oxidative stress insult, the synthesis of protective DHA derivatives increased while AA synthesis decreased over time.
“Our findings demonstrate that DHA and the induction of docosanoid synthesis is necessary for preconditioning protection, and thus daily survival, of photoreceptor and RPE cells,” adds Bazan. “Since omega-3 impairments are associated with neuroinflammation, which contributes to photoreceptor cell dysfunction and death, enhancing the synthesis of docosanoids may provide an opportunity for halting or ameliorating debilitating retinal degenerative diseases, such as the dry form of age-related macular degeneration,” concludes Bazan.
The LSU Health New Orleans Neuroscience Center research team also included Drs. William Gordon and Bokkyoo Jun, as well as graduate students Khanh Do and Eric Knott.
This work was supported by National Eye Institute grant EY005121, National Institute of General Medical Sciences GM103340, and the Eye, Ear, Nose and Throat Foundation.