From The Complete Herbal Guide:

 Besides being one of the most potent sources of anti-inflammatory  omega-3s, salmon also contains dimethylaminoethanol (DMAE). DMAE  promotes healthy skin because it protects the integrity of cell  membranes. Strengthening cell membranes guards against their  deterioration that causes premature aging. This nutrient also helps to  prevent the production of arachidonic acid (AA), an inflammation  precursor that leads to wrinkle formation. And that’s not all. DMAE  works in conjunction with B vitamins to increases levels of  acetylcholine, a neurotransmitter essential for proper muscle  functioning that can keep your face looking toned and firm. (Read more.)