This article originally appeared on Live in the Now.
Research from LSU Health New Orleans has discovered that a compound in oily fish can help vision cells in the eye to survive when injured. The authors compare the benefit to a form of vaccination.
Fish varieties like salmon, trout and tuna are rich sources of omega-3 fatty acids, which have been linked to an array of health benefits. One omega-3 fat, docosahexaenoic acid (DHA), and its derivatives precondition the survival of photoreceptor and retinal pigment epithelial (RPE) cells, which are critical for vision.
“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,” said Nicolas Bazan, M.D., Ph.D., Boyd Professor and Director of LSU Health New Orleans Neuroscience Center of Excellence.
How Preconditioning Works
A preconditioning stimulus is a stressor that triggers a protective response to a future damaging event, the team explains. For example, the preconditioning response occurs when the blood supply to an organ is temporarily interrupted. The protective response to the initial interruption would still be in effect when subsequent ones happen. This benefit is similar to the immunity against future disease that a vaccine confers.
“This happens in the heart, brain and retina, as well as other organs,” Bazan said. “To harness the therapeutic potential of preconditioning, it is very important to identify the molecules directly involved.”
Fish oil contains two types of polyunsaturated fatty acids (PUFAs) that have very different actions. Omega-3 PUFAs like DHA and its derivatives have strong anti-inflammatory and pro-resolving properties, while omega-6 PUFAs like arachidonic acid (AA) have harm-producing pro-inflammatory actions.
The authors found that although the two types of PUFAs are released at the same time, DHA mitigates the action of AA. When the team exposed the retinal cells of humans and rats to the stress of constant light, prior DHA supplementation protected the cells from destruction.
“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,” said 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,” concluded Bazan.
The study was published in the journal Cellular and Molecular Neurobiology.
Recipe: Salmon Bisque
Holly Clegg, bestselling healthy cookbook author of Trim & Terrific and the Eating Well Series shares this comforting recipe with Live in the Now.
“A mouth-watering salmon lover’s soup — easy and elegant. Don’t let bisque intimidate you, as it is just a thick, creamy soup. Great recipe to use leftover salmon.”
Makes 8 (1-cup) servings
- 2 tablespoons butter
- 1/4 cup finely chopped onion
- 1/3 cup all-purpose flour
- 1 cup fat-free low-sodium chicken broth
- 1 cup organic half-and-half
- 1/2 cup organic whole milk
- 1 tablespoon tomato paste
- 1/2 cup white wine
- 2 cups cooked, skin removed, flaked salmon fillet (pan sauté, broil, grilled or poached)
- 1 teaspoon dried dill weed leaves
- Salt and white pepper to taste
- In large nonstick pot, melt butter and sauté onion about 3 minutes, cooking until tender.
- Gradually blend in flour, stirring 1 minute. Add broth, half-and-half, milk and tomato paste, stirring constantly. Bring to boil, reduce heat, stirring until mixture starts to thicken. Add white wine and continue cooking until thickened.
- Add flaked salmon, dill weed and season to taste.