Apoaequorin
Apoaequorin is a protein isolated from the jellyfish Aequorea victoria. It is the active ingredient in some supplements marketed for memory and brain health (e.g., Prevagen®). Increased calcium levels in brain cells are associated with cell death and aging, so agents that help maintain healthy calcium levels do have potential for promoting brain health and preventing dementia. Apoaequorin, however, has a chemical structure that is likely broken down in the gut before reaching the brain, raising serious doubts about its potential benefit.