According to health experts, oxidative stress and inflammation are the underlying reasons for heart disease. In turn, these are believed to be caused by overproduction of damage-inducing reactive oxygen species (ROS) and reactive nitrogen species (RNS).
Both ROS and RNS trigger the activity of other signaling molecules such as nuclear factor kappa B or NFKB, which causes damage to the lining of blood vessel walls - increasing the risk of onset and progression of plaque formation or atherosclerosis, arrhythmia and stroke.
In spite of this known connection between oxidative stress, inflammation and heart disease, there is currently no known treatment for heart disease that tries to prevent or reduce these two risk factors.
That’s not because of a shortage of candidates.
For instance, a 2008 review of preclinical data by researchers at the University of Hawaii looked at how carotenoid antioxidants prevent oxidative stress and inflammation. They found that data from multiple species strongly support a therapeutic role for astaxanthin as an antioxidant and anti-inflammatory agent. In fact astaxanthin seems to be the perfect candidate for development as a therapy for treating heart disease.
The main natural source of astaxanthin is the microalga H. pluvialis. Only plankton, algae, certain bacteria and fungi are able to make astaxanthin on their own, while animals, including us humans, must get carotenoids from our diet.
Astaxanthin is the reason why salmon, shrimp, red fish, and lobster - and feathers of birds such as flamingoes and quail - have that typical, bright reddish-orange color. Both its color and powerful antioxidant activity are because of its chemical structure.
Carotenoid antioxidants are known for being able to effectively neutralize damage-causing free radicals. When researchers determined the free radical-fighting capacity of various carotenoids, they found that vitamin E was the most effective in terms of its electron donor capacity, whereas astaxanthin was the most effective in terms of its electron acceptor capacity.
So far, astaxanthin has shown the following activities under experimental conditions:
- Protects mitochondria - the cell’s furnaces for making energy - against oxidative stress caused by oxygen-derived free radicals and also boosts respiration, increasing levels of cellular energy.
- Protects the brain against free radicals because of its unique ability to cross the blood-brain barrier.
- Protects against many types of cancer in cultured cells and animal models.
- Prevents progression of many of the complications associated with type II diabetes when given in combination with an extract from French maritime pine bark.
- Significantly enhances immune function.
However, astaxanthin has not yet been extensively tested in humans - and previous clinical trials with carotenoid antioxidants such as vitamin E and beta-carotene have been disappointing.
Health experts are not sure if this means antioxidants are ineffective as therapeutic agents, or whether their mechanisms of action still have to be properly understood and their appropriate targets and doses determined.
While the jury’s still out on the effectiveness of carotenoid antioxidants in therapy, all the signs point to astaxanthin as a potential therapy for heart disease and other disorders.