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The role of astaxanthin in brain and eye health
Algae may be pond scum (literally), but that doesn’t mean they’re useless. On the contrary, algae produce a substance with major benefits for human and animal health: astaxanthin.[1]
In nature, astaxanthin serves to protect the algal cysts from the sun’s harmful ultraviolet rays,[2] so perhaps it is not surprising it protects our skin from them as well.[3] Numerous studies have shown that astaxanthin can shield the brain, eyes, skin, and many other organs against the oxidative damage associated with aging. Moreover, studies suggest that astaxanthin supports long-term memory, and may even protect the brain against neurodegenerative disorders such as Alzheimer’s disease and Parkinson’s disease.[4]
A single (3.5 ounce) serving of salmon provides up to 3.8 mg of astaxanthin.[5] However, the richest natural source of astaxanthin is the freshwater algae, Haematococcus pluvialis, which contains a whopping 3,800 milligrams (3.8 grams) of astaxanthin per 3.5 ounces (dry weight).[4],[6]
Thankfully, you don’t need to gulp down algae like the salmon does to obtain astaxanthin. Algae are now cleanly farmed to maximize the production of this valuable antioxidant, and the resulting purified natural astaxanthin is available as a supplement ingredient.[4],[7] Importantly, one should seek out a natural astaxanthin product because it has 90 times more intracellular antioxidant activity than synthetic (laboratory-made) astaxanthin, which also is available on the market.[8]
Effects of astaxanthin on the brain
The brain is especially vulnerable to oxidative stress and inflammation, processes that contribute to age-related memory loss and neurodegenerative diseases.[9],[10] Astaxanthin (AST) has a unique chemical structure that allows it to cross the blood-brain barrier and thus to shield brain cells against damage.[11],[12],[13]
The data from preclinical studies are particularly exciting, because they show that AST not only prevents oxidative damage, but also causes a measurable improvement in memory and cognition.
Preclinical studies suggest that AST has an array of beneficial effects within the brain:
- AST protects the brain against the toxic effects of aluminum,[14] a metal that has been linked to Alzheimer’s disease.[15]
- AST protects the brain against the toxic effects of environmental tobacco smoke, a pollutant that impairs cognitive function.[16]
- AST also protects the brain and eyes against damage due to chemotherapy drugs (e.g., “chemobrain”).[17],[18]
- AST induces the synthesis of nuclear factor erythroid 2 (NF-E2)-related factor (Nrf2), a master regulator of the body’s antioxidant response.[19]
- AST ameliorates age-related damage in the hippocampus, a brain region essential for long-term memory, spatial processing, and navigation.[20]
- AST stimulates the proliferation of brain stem cells, which can give rise to new neurons to replace degenerating cells.[21]
- Consistent with the above, AST boosts the number of mature neurons in the brain.[22]
The data from preclinical studies are particularly exciting, because they show that AST not only prevents oxidative damage, but also causes a measurable improvement in memory and cognition.[11],[21],[23] Beneficial effects of AST have been demonstrated in animals with high blood pressure (hypertension),[24] diabetes,[25] and brain injury or stroke.[26],[27],[28]
Alzheimer’s disease (AD) is associated with the accumulation of amyloid β peptides, which form aggregates (clumps) that lead to neuronal damage, cell death, and memory problems.[29],[30] AST is capable of protecting neurons from the damaging effects of amyloid β peptides.[12],[31] A combination of AST and fish oil (a source of omega-3 polyunsaturated fatty acids) was shown to enhance the beneficial effects of AST in an animal model of AD.[32],[33]
In addition to its direct antioxidant effects, AST helps prevent the accumulation of phospholipid hydroperoxides (PLOOH) in red blood cells.[12],[34] PLOOH are the primary oxidation products of phospholipids, and their accumulation causes a reduction in oxygen transport to the brain, which contributes to the progression of dementia.[35],[36],[37]
In an animal model of Parkinson’s disease, dopaminergic neuron death was reduced by supplementation with AST.
Parkinson’s disease (PD) is associated with the degeneration of dopaminergic neurons in the substantia nigra within the brain, leading to the decline of dopamine that is characteristic of PD. In an animal model of PD, dopaminergic neuron death was reduced by supplementation with AST.[12],[38],[39] The results were particularly significant in younger versus older animals. Thus AST may provide a valuable nutritional strategy for brain support during aging.
Human clinical trials of AST have begun. In several studies, AST was shown to support cognitive and memory functions in healthy aging adults.[40],[41],[42] In one randomized double-blind placebo-controlled study, healthy middle-aged and elderly subjects who complained of age-related forgetfulness showed improvements in learning and memory test scores after 12 weeks of supplementation with 6 mg or 12 mg AST daily.[41]
Effects of astaxanthin on the eyes
Aging is associated with conditions such as dry eye, cataracts, glaucoma, and macular degeneration. Many of these effects are a result of ultaviolet (UV) exposure, which causes oxidative damage to the cornea, lens, and retina of the eye.[43],[44],[45] AST may help protect the eyes against UV damage,[46],[47],[48],[49] in a manner similar to that observed for lutein, another member of the carotenoid family.[50]
AST was shown to prevent cataract formation in the lens, and to protect the retina against damage associated with elevated intraocular pressure, a condition associated with glaucoma.
In animal models, supplementation with AST was shown to protect against photokeratitis (a condition in which the cornea, the clear dome on the front surface of the eye, becomes inflamed in response to UV light).[45],[46],[51] AST also was shown to prevent cataract formation in the lens,[52] and to protect the retina against damage associated with elevated intraocular pressure, a condition associated with glaucoma.[53]
Human studies show that natural AST (6 mg daily) can reduce eye soreness, dryness, fatigue, and blurred vision.[54],[55] In addition, AST was shown to support healthy blood flow in the choroid, the vascular layer of the eye.[56] A placebo-controlled clinical trial in healthy adults showed that four weeks of AST supplementation (6 mg daily) improved retinal capillary blood flow, another indicator of eye health.[57]
The carotenoids lutein and zeaxanthin have been shown to protect against age-related macular degeneration (AMD),[58],[59] and AST may have similar or complementary effects. In a study of individuals with AMD, volunteers who took a daily carotenoid and antioxidant supplement containing AST, lutein, and zeaxanthin, were more likely to report clinically meaningful stabilization/improvements in visual function through 24 months compared with non-treated subjects.[60]
Wrapping up
Numerous studies suggest that astaxanthin can support brain function and eye health as we age, and protect against the cumulative effects of environmental toxins and UV exposure. In sum, astaxanthin is truly a gift from algae (we promise not to call them pond scum anymore!).
Click here to see References[1] Wells ML, et al. Algae as nutritional and functional food sources: revisiting our understanding. J Appl Phycol. 2017;29(2):949-82.
[2] Kobayashi M. Astaxanthin biosynthesis enhanced by reactive oxygen species in the green alga Haematococcus pluvialis. Biotech Bioprocess Engineering. 2003 Dec 1;8(6):322.
[3] Ito N, et al. The protective role of astaxanthin for uv-induced skin deterioration in healthy people-a randomized, double-blind, placebo-controlled trial. Nutrients. 2018 Jun 25;10(7).
[4] Wu H, et al. Astaxanthin as a potential neuroprotective agent for neurological diseases. Mar Drugs. 2015 Sep 11;13(9):5750-66.
[5] Ambati RR, et al. Astaxanthin: sources, extraction, stability, biological activities and its commercial applications–a review. Mar Drugs. 2014 Jan 7;12(1):128-52.
[6] Shah MM, et al. Astaxanthin-producing green microalga Haematococcus pluvialis: from single cell to high value commercial products. Front Plant Sci. 2016 Apr 28;7:531.
[7] Kidd P. Astaxanthin, cell membrane nutrient with diverse clinical benefits and anti-aging potential. Altern Med Rev. 2011 Dec;16(4):355-64.
[8] Capelli B, et al. Synthetic astaxanthin is significantly inferior to algal-based astaxanthin as an antioxidant and may not be suitable as a human nutraceutical supplement. Nutrafoods. 2013 Dec 1;12(4):145-52.
[9] Beckhauser TF, et al. Reactive oxygen species: physiological and physiopathological effects on synaptic plasticity. J Exp Neurosci. 2016 Sep 4;10(Suppl 1):23-48.
[10] Liu Z, et al. Oxidative stress in neurodegenerative diseases: from molecular mechanisms to clinical applications. Oxid Med Cell Longev. 2017;2017:2525967.
[11] Grimmig B, et al. Neuroprotective mechanisms of astaxanthin: a potential therapeutic role in preserving cognitive function in age and neurodegeneration. Geroscience. 2017 Feb;39(1):19-32.
[12] Galasso C, et al. On the neuroprotective role of astaxanthin: new perspectives? Mar Drugs. 2018 Jul 24;16(8):247.
[13] Petri D, Lundebye AK. Tissue distribution of astaxanthin in rats following exposure to graded levels in the feed. Comp Biochem Physiol C Toxicol Pharmacol. 2007 Mar;145(2):202-9.
[14] Al-Amin MM, et al. Astaxanthin ameliorates aluminum chloride-induced spatial memory impairment and neuronal oxidative stress in mice. Eur J Pharmacol. 2016 Apr 15;777:60-9.
[15] Mirza A, et al. Aluminum in brain tissue in familial Alzheimer’s disease. J Trace Elem Med Biol. 2017 Mar;40:30-36.
[16] Yang X, et al. Astaxanthin attenuates environmental tobacco smoke-induced cognitive deficits: a critical role of p38 MAPK. Mar Drugs. 2019 Jan 3;17(1):24.
[17] El-Agamy SE, et al. Astaxanthin ameliorates doxorubicin-induced cognitive impairment (chemobrain) in experimental rat model: impact on oxidative, inflammatory, and apoptotic machineries. Mol Neurobiol. 2018 Jul;55(7):5727-40.
[18] Findik H, et al. The protective effects of astaxanthin against cisplatin-induced retinal toxicity. Cutan Ocul Toxicol. 2019 Mar;38(1):59-65.
[19] Saw CL, et al. Astaxanthin and omega-3 fatty acids individually and in combination protect against oxidative stress via the Nrf2-ARE pathway. Food Chem Toxicol. 2013 Dec;62:869-75.
[20] Wu W, et al. Astaxanthin alleviates brain aging in rats by attenuating oxidative stress and increasing BDNF levels. Food Funct. 2014 Jan;5(1):158-66.
[21] Kim JH, et al. Astaxanthin improves stem cell potency via an increase in the proliferation of neural progenitor cells. Int J Mol Sci. 2010;11(12):5109-19.
[22] Yook JS, et al. Astaxanthin supplementation enhances adult hippocampal neurogenesis and spatial memory in mice. Mol Nutr Food Res. 2016 Mar;60(3):589-99.
[23] Zhang X, et al. Impact of astaxanthin-enriched algal powder of Haematococcus pluvialis on memory improvement in BALB/c mice. Environ Geochem Health. 2007 Dec;29(6):483-9.
[24] Hussein G, et al. Antihypertensive and neuroprotective effects of astaxanthin in experimental animals. Biol Pharm Bull. 2005 Jan;28(1):47-52.
[25] Feng Y, et al. The protective effect of astaxanthin on cognitive function via inhibition of oxidative stress and inflammation in the brains of chronic T2DM rats. Front Pharmacol. 2018 Jul 10;9:748.
[26] Ji X, et al. Astaxanthin improves cognitive performance in mice following mild traumatic brain injury. Brain Res. 2017 Mar 15;1659:88-95.
[27] Nai Y, et al. Protective effect of astaxanthin on acute cerebral infarction in rats. Hum Exp Toxicol. 2018 Sep;37(9):929-36.
[28] Wang Y, et al. Protective effects of astaxanthin on subarachnoid hemorrhage-induced early brain injury: reduction of cerebral vasospasm and improvement of neuron survival and mitochondrial function. Acta Histochem. 2019 Jan;121(1):56-63.
[29] Haass C, Selkoe DJ. Soluble protein oligomers in neurodegeneration: lessons from the Alzheimer’s amyloid beta-peptide. Nat Rev Mol Cell Biol. 2007 Feb;8(2):101-12.
[30] Irvine GB, et al. Protein aggregation in the brain: the molecular basis for Alzheimer’s and Parkinson’s diseases. Mol Med. 2008 Jul-Aug;14(7-8):451-64.
[31] Lobos P, et al. Astaxanthin protects primary hippocampal neurons against noxious effects of Aβ-oligomers. Neural Plast. 2016;2016:3456783.
[32] Mattei R, et al. Astaxanthin limits fish oil-related oxidative insult in the anterior forebrain of Wistar rats: putative anxiolytic effects? Pharmacol Biochem Behav. 2011 Sep;99(3):349-55.
[33] Nolan JM, et al. Nutritional intervention to prevent Alzheimer’s disease: potential benefits of xanthophyll carotenoids and omega-3 fatty acids combined. J Alzheimers Dis. 2018;64(2):367-78.
[34] Nakagawa K, et al. Antioxidant effect of astaxanthin on phospholipid peroxidation in human erythrocytes. Br J Nutr. 2011 Jun;105(11):1563-71.
[35] Ajmani RS, et al. Hemodynamic changes during aging associated with cerebral blood flow and impaired cognitive function. Neurobiol Aging. 2000 Mar-Apr;21(2):257-69.
[36] Mohanty JG, et al. Do red blood cell-beta-amyloid interactions alter oxygen delivery in Alzheimer’s disease? Adv Exp Med Biol. 2008;614:29-35.
[37] Leijenaara JF, et al. Lower cerebral blood flow in subjects with Alzheimer’s dementia, mild cognitive impairment, and subjective cognitive decline using two-dimensional phase-contrast magnetic resonance imaging. Alzheimers Dement (Amst). 2017 Nov 2;9:76-83.
[38] Lee DH, et al. Astaxanthin protects against MPTP/MPP+-induced mitochondrial dysfunction and ROS production in vivo and in vitro. Food Chem Toxicol. 2011 Jan;49(1):271-80.
[39] Grimmig B, et al. Astaxanthin is neuroprotective in an aged mouse model of Parkinson’s disease. Oncotarget. 2017 Dec 28;9(12):10388-10401.
[40] Satoh A, et al. Preliminary clinical evaluation of toxicity and efficacy of a new astaxanthin-rich Haematococcus pluvialis extract. J Clin Biochem Nutr. 2009 May;44(3):280-4.
[41] Hayashi M, et al. Effect of astaxanthin-rich extract derived from Paracoccus carotinifaciens on cognitive function in middle-aged and older individuals. J Clin Biochem Nutr. 2018 Mar;62(2):195-205.
[42] Katagiri M, et al. Effects of astaxanthin-rich Haematococcus pluvialis extract on cognitive function: a randomised, double-blind, placebo-controlled study. J Clin Biochem Nutr. 2012 Sep;51(2):102-7.
[43] Belleza I. Oxidative stress in age-related macular degeneration: Nrf2 as therapeutic target. Front Pharmacol. 2018 Nov 5;9:1280.
[44] Lin JB, et al. A glimpse at the aging eye. NPJ Aging Mech Dis. 2016 Mar 10;2:16003.
[45] Linetsky M, et al. UVA light-excited kynurenines oxidize ascorbate and modify lens proteins through the formation of advanced glycation end products: implications for human lens aging and cataract formation. J Biol Chem. 2014 Jun 13;289(24):17111-23.
[46] Otsuka T, et al. Protective effects of a dietary carotenoid, astaxanthin, against light-induced retinal damage. J Pharmacol Sci. 2013;123(3):209-18.
[47] Harada F, et al. Protective effects of oral astaxanthin nanopowder against ultraviolet-induced photokeratitis in mice. Oxid Med Cell Longev. 2017;2017:1956104.
[48] Yoshihisa Y, et al. Astaxanthin, a xanthophyll carotenoid, inhibits ultraviolet-induced apoptosis in keratinocytes. Exp Dermatol. 2014 Mar;23(3):178-83.
[49] Li Z, et al. Astaxanthin protects ARPE-19 cells from oxidative stress via upregulation of Nrf2-regulated phase II enzymes through activation of PI3K/Akt. Mol Vis. 2013 Jul 25;19:1656-66.
[50] Buscemi S, et al. The effect of lutein on eye and extra-eye health. Nutrients. 2018 Sep 18;10(9):1321.
[51] Shimokawa T, et al. Efficacy of high-affinity liposomal astaxanthin on up-regulation of age-related markers induced by oxidative stress in human corneal epithelial cells. J Clin Biochem Nutr. 2019 Jan;64(1):27-35.
[52] Ishikawa S, et al. Effect of astaxanthin on cataract formation induced by glucocorticoids in the chick embryo. Curr Eye Res. 2015 May;40(5):535-40.
[53] Cort A, et al. Suppressive effect of astaxanthin on retinal injury induced by elevated intraocular pressure. Regul Toxicol Pharmacol. 2010 Oct;58(1):121-30.
[54] Shiratori K, et al. The effects of astaxanthin on accommodation and asthenopia—efficacy identification study in healthy volunteers. Clin Med. 2005 Jun;21(6):637-50.
[55] Nagaki Y, et al. [The supplementation effect of astaxanthin on accommodation and asthenopia.] J. Clin. Ther. Med. 2006;22(1):41-54.
[56] Saito M, et al. Astaxanthin increases choroidal blood flow velocity. Graefes Arch Clin Exp Ophthalmol. 2012 Feb;250(2):239-45.
[57] Nagaki Y, et al. [The effect of astaxanthin on retinal capillary blood flow in normal volunteers.] J Clin Ther Med. 2005;21(5):537-42.
[58] Jia YP, et al. The pharmacological effects of lutein and zeaxanthin on visual disorders and cognition diseases. Molecules. 2017 Apr 20;22(4):610.
[59] Age-Related Eye Disease Study 2 (AREDS2) Research Group. Secondary analyses of the effects of lutein/zeaxanthin on age-related macular degeneration progression: AREDS2 report No. 3. JAMA Ophthalmol. 2014 Feb;132(2):142-9.
[60] Piermarocchi S, et al. Carotenoids in Age-related Maculopathy Italian Study (CARMIS): two-year results of a randomized study. Eur J Ophthalmol. 2012 Mar-Apr;22(2):216-25.
The information provided is for educational purposes only. Consult your physician or healthcare provider if you have specific questions before instituting any changes in your daily lifestyle including changes in diet, exercise, and supplement use.
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Marina MacDonald, MS, PhD
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