Astaxanthin is a red pigment found in fish, shrimp, and some microalgae. It is a potent antioxidant that has been proven to help with cardiovascular risks, protect the brain, and modulation the immune system. Read this post to learn more about the proven benefits of astaxanthin and how it can help optimize your health.
What is Astaxanthin?
Astaxanthin (ASTA) is a naturally-occurring orange-red pigment carotenoid found in algae, shrimp, lobster, crab, and salmon.
Astaxanthin is made by the green microalgae Haematococcus pluvialis, Chlorella zofingiensis, Chlorococcum, and yeast Phaffia rhodozyma (R).
The green algae H. pluvialis makes high amounts of astaxanthin when its condition is unfavorable, including high UV exposure, which is why astaxanthin has strong antioxidative properties (R).
Animals that eat these microalgae or yeast then absorb astaxanthin into their bodies, which is why wild shrimp, lobster, crab, and salmon have bright red-orange colors (R).
Wild salmon can have up to 26 – 38 mg of astaxanthin per kg of body weight, whereas farmed Atlantic salmons typically have 6 – 8 mg of astaxanthin per kg of body weight (R).
Astaxanthin is not converted to vitamin A in the human body.
Like other carotenoids, astaxanthin has self-limited absorption orally and no toxicity was detected when tested at very high doses (up to 465 mg/kg/day for male and 557 mg/kg/day for female) in rats (R, R2).
However, overconsumption of astaxanthin can turn animal skin and tissues red, which is why astaxanthin is used in feed for farmed seafood and fish (R).
Pharmacokinetics of Astaxanthin
Astaxanthin is a highly fat-soluble substance, which means that it is better absorbed when consumed with oil (R).
When astaxanthin is ingested, it is digested and absorbed in a similar manner as fat, which means it is assembled into chylomicrons. The chylomicrons are absorbed into lymph circulation before remnants of astaxanthin are digested by lipoprotein lipases. Astaxanthin is then assimilated into lipoprotein particles to get transported into tissues (R).
This means astaxanthin can more readily affect the metabolism of fat and cholesterol, especially when it relates to cardiovascular health.
Ingested astaxanthin is metabolized by first-pass liver metabolism primarily by liver CYP450 in rats (R).
Astaxanthin is found in all tissues studied, except for the heart (R).
Astaxanthin as a Potent Antioxidant
The structure of astaxanthin allows it to span across cell membranes or stay outside of cell membranes, allowing it to protect cell membranes from both inside and outside the cell (R).
1) Astaxanthin Mitigates Oxidative Effects of Diabetes
Generally, high blood sugar causes high levels of oxidative stress in diabetic patients. Astaxanthin can protect pancreatic β-cells (which produce insulin) from oxidative stress caused by high blood sugar (R).
It is also a good agent in the recovery of lymph cell dysfunctions associated with diabetic rats (R).
It also prevents diabetic nerve disorder by reduction of the oxidative stress and renal cell damage (R).
2) Astaxanthin Reduces Risks of Cardiovascular Disease
In a mouse model, astaxanthin delays and reduces blood clotting in the blood vessels, and increases blood flow (R).
3) Astaxanthin Reduces Heart Damage from Heart Attacks
In rats, rabbits, and dogs heart attack models, pre-treatment of the animals with a synthetic astaxanthin reduce the damage on the heart that was caused by the heart attacks in a dose-dependent manner (R, R2, R3).
4) Astaxanthin Helps with Non-Alcoholic Fatty Liver Disease
Astaxanthin improves insulin sensitivity, liver inflammation, and reduces fatty liver in mice on a high-fat diet. In addition, astaxanthin helps with fatty liver in humans comparing to placebo (R).
5) Astaxanthin Inhibits Cancer
Astaxanthin inhibits chemical-induced fibrosarcoma by activating the anti-cancer immune system (R).
In cell cultures, astaxanthin inhibits the growth of colon, fibrosarcoma, breast, and prostate cancer cells and embryonic fibroblasts, with activation of tumor-suppressor genes such as p53 (R).
6) Astaxanthin Modulates the Immune Responses
Combined astaxanthin and fish oil supplementation modulate lymphocyte function in rats (R).
Astaxanthin enhanced antibody production and decreased immune response in older animals after dietary supplementation (R).
Supplementation with 2 mg astaxanthin for 8 weeks enhanced immune response and reduced CRP in young healthy females (R).
7) Astaxanthin Protects the Stomach Lining from H. pylori and Ulcers
Mice pretreated with astaxanthin for 1 hour before ulcer induction had significantly decreased gastric ulcers. These results suggest that astaxanthin has antioxidant properties and exerts a protective effect against ulcer formation in murine models (R).
8) Astaxanthin Protects Against UV Damage
Astaxanthin protects against UVA-induced skin photoaging such as sagging and wrinkles (R).
9) Astaxanthin Reduces Exercise Fatigue
Antioxidant effects of astaxanthin can significantly delay exhaustion in a forced swimming test in rats (R).
10) Astaxanthin Protects the Mitochondria from Oxidative Stress
Astaxanthin is effective at improving mitochondrial function by protecting the mitochondria from oxidative stress (R).
Dietary astaxanthin improves mitochondrial function in white blood cells of dogs, most likely by alleviating oxidative damage to DNA and proteins (R).
Astaxanthin Protects the Nervous System
11) Astaxanthin Reduces Brain Damages from Stroke
Pre-treatment with high dose (80 mg/kg) astaxanthin significantly reduced brain damage from a stroke in rats (R).
Mice pre-treated with astaxanthin performs better than mice that were not treated with astaxanthin in a learning performance test after a stroke (R).
12) Astaxanthin Helps Recovery from Traumatic Brain Injury
Astaxanthin reduces brain swelling after a traumatic brain injury in mice (R).
Astaxanthin appears to help speed physical recovery from a traumatic brain injury in mice, albeit with no effects on cognitive function (R).
13) Astaxanthin May Protect Against Alzheimer’s Disease
In a cell model, astaxanthin protects neuronal cells from beta-amyloid-induced toxicity, suggesting that astaxanthin may protect against Alzheimer’s Disease (R).
Astaxanthin protects hippocampal neurons against the effects of beta-amyloid toxicity (R).
Astaxanthin combats brain aging in rats by increasing BDNF levels (R).
The effects of astaxanthin on the aging brain differences between genders in rats (R).
14) Astaxanthin may Protect Against and Treat Parkinson’s Disease
Due to its anti-inflammatory, antioxidant, and mitochondrial protective effects, astaxanthin has been proposed as a potential therapeutic agent for Parkinson’s Disease (R).
15) Astaxanthin Protects the Eyes from Bacterial Inflammation
16) Astaxanthin Helps with High Blood Pressure
Beneficial results have been observed at 2 mg in humans with dose-dependent effects at 8 mg (R).
Side Effects and Warnings
Currently, there is no direct evidence demonstrating the harm of using astaxanthin in humans or animals.
While there is no large-scale study to demonstrate long-term safety or harmful effects of astaxanthin in humans, several such studies have demonstrated conclusively that long-term supplementation of similar antioxidants including carotenoids and lutein increases the risks of cancer, especially among smokers (R, R).
- ASTA is a member of the xanthophylls, because it contains not only carbon and hydrogen but also oxygen atoms ((R).
- However, the synthesis of ASTA is not possible in humans. This also means that excess intake will not cause vitamin A toxicity (R).
- ASTA and canthaxanthin are scavengers of free radicals, chain-breaking antioxidants and potent quenchers of reactive oxygen and nitrogen species including singlet oxygen, single and two electron oxidants (R).
- ASTA inhibits NF-κB and Wnt signaling by downregulating the key regulatory enzymes IKKβ and GSK-3β. Analysis of gene expression and docking interactions reveals that inhibition of these pathways is mediated via inactivation of the upstream signaling kinases Erk/Akt by ASTA (R).
- Additionally, ASTA induced caspase-mediated mitochondrial apoptosis by downregulating the expression of antiapoptotic Bcl-2, p-Bad, and survivin and upregulation of proapoptotic BASTA and Bad, accompanied by efflux of Smac/Diablo and cytochrome-c into the cytosol and induced cleavage of poly (ADP-ribose) polymerase (PARP) (R).
- ASTA, as well as its esters, showed 80% anti-lipid peroxidation activity in ethanol-induced gastric ulcer and skin cancer in rats (R).
- Astaxanthin has been shown to induce expression of Nrf2 and its downstream antioxidant-related genes including SOD, GPx, and UCP-2 in mouse liver (R).
- Adding H. pluvialis extract to cell cultures of many cancer cell lines and a fibroblast cell line inhibit cell growth while upregulating p53, p21(WAF-1/CIP-1), and p27 expression. At the same time, apoptotic and inflammatory genes were upregulated (R).
- Astaxanthin supplementation (2 mg) decreases plasma CRP, but with no difference in TNF and IL-2 concentration, while plasma IFN-gamma and IL-6 increases in subjects given 8 mg of astaxanthin (R).
- Astaxanthin protects eyes against bacterial LPS by suppressing NO, PGE2, and TNF-alpha by directly blocking NOS activity and inhibiting NF-kB signaling in rats (R, R2).