scientific evidence
literature and references
Polypodium Leucotomos Extract (PLE)
Background
Polypodium leucotomos (PL) is a fern native to Central and South America where it has a historical role in traditional medicine. Polypodium leucotomos extract (PLE) is composed of phenolic compounds and acid molecules notably p-coumaric, ferulic, caffeic, and vanillic acid. Its chemical composition endows it with photoprotective qualities. It has been studied extensively in both topical and oral formulations in in-vivo human and murine models. It is absorbed rapidly and efficiently (70-100%) and metabolized in 24 hours by the liver(1). It is currently available in topical and oral formulations and has been utilized in Europe for over a decade.
Clinical Features
- Actinic Keratosis: Reduction in new AK development over 6 and 12 mo in patients with severe actinic damage when combined with SPF 100 compared to SPF 100 alone(2).
- UV Erythema Tolerance: PLE increases minimal erythemal dose (MED) in human UV erythema testing(3).
- Delays UVR-induced tumor development in mice(4).
- Protection from visible light damage (such as blue light from digital devices)(1).
- Also demonstrated to have applications for vitiligo, PMLE, and other photosensitive conditions with regard to light tolerance.
Dosing
- Recommended oral dose is 240mg daily in the morning. When excessive sun exposure is expected, 240mg is recommended one hour before exposure and after 2-3 hrs.
- Topically available as sunscreen booster
Safety
- PLE has a good safety profile without side effects and has been shown to be safe in children. No data is available with pregnancy(5, 6, 7).
Mechanism of Action
- Antioxidant(8, 9): due to polyphenolic compounds and is able to inhibit membrane damage and lipid peroxidation in fibroblasts and keratinocytes1 PLE is also a direct ROS scavenger against superoxide anion, hydrozyl oxygen and oxygen peroxide and results in reduced levels of 8-OH-dG, a marker of cellular oxidative damage1
- Reduction in DNA Damage (8, 9): Reduction of cyclobutane pyrimidine dimer (CPD) production after UVR10 induces activation of oncosuppressor p53 and decreases UV induced mitochondrial DNA damage as well(1)
- Immunomodulatory Activity: Inhibition of t-UCA isomerization11 decreases UV-induced COX-2 expression(1)
- Protection of skin immunosurveillance: (prevention of immune cell depletion upon UV irradiation)(8, 12, 13)
- Extracellular Matrix: Inhibits MPP-1,2,3 and 9 and stimulates TGF-b, elastin and fibrillin(1)
- Visible Light Protection: inhibits increase in MMP-1, protects fibrillin and elastin, reduces opsin-3 activation, preventing melanin photooxidation and photodegradation in human cell lines(1)
- Calzari P, Vaienti S, Nazzaro G. Uses of Polypodium leucotomos Extract in Oncodermatology. J Clin Med. 2023 Jan 14;12(2):673. doi: 10.3390/jcm12020673. PMID: 36675602; PMCID: PMC9861608.
- Pellacani G, Peris K, Ciardo S, Pezzini C, Tambone S, Farnetani F, Longo C, Chello C, González S. The combination of oral and topical photoprotection with a standardized Polypodium leucotomos extract is beneficial against actinic keratosis. Photodermatol Photoimmunol Photomed. 2023 Jul;39(4):384-391. doi: 10.1111/phpp.12870. Epub 2023 Mar 31. PMID: 36892441.
- Kohli et al. The impact of oral Polypodium leucotomos extract on ultraviolet B response: A human clinical study. J Am Acad Dermatol. 2017 Jul;77(1):33-41.e1
- Rodríguez-Yanes E, Cuevas J, González S, Mallol J. Oral administration of Polypodium leucotomos delays skin tumor development and increases epidermal p53 expression and the anti-oxidant status of UV-irradiated hairless mice. Exp Dermatol. 2014 Jul;23(7):526-8. doi: 10.1111/exd.12454. PMID: 24862559.
- Nestor MS, Berman B, Swenson N. Safety and Efficacy of Oral Polypodium leucotomos Extract in Healthy Adult Subjects. J Clin Aesthet Dermatol. 2015;8(2):19-23.
- Murbach TS, Béres E, Vértesi A, et al. A comprehensive toxicological safety assessment of an aqueous extract of Polypodium leucotomos (Fernblock(®)). Food Chem Toxicol. 2015;86:328-341. doi:10.1016/j.fct.2015.11.008
- Ramírez-Bosca A, Zapater P, Betlloch I, et al. Polypodium leucotomos extract in atopic dermatitis: a randomized, double-blind, placebo-controlled, multicenter trial. Actas Dermosifiliogr. 2012;103(7):599-607. doi:10.1016/j.ad.2012.01.008
- Mulero M, Rodríguez-Yanes E, Nogués MR, et al. Polypodium leucotomos extract inhibits glutathione oxidation and prevents Langerhans cell depletion induced by UVB/UVA radiation in a hairless rat model. Exp Dermatol. 2008;17(8):653-658. doi:10.1111/j.1600-0625.2007.00684.x
- Zattra E, Coleman C, Arad S, et al. Polypodium leucotomos extract decreases UV-induced Cox-2 expression and inflammation, enhances DNA repair, and decreases mutagenesis in hairless mice. Am J Pathol. 2009;175(5):1952-1961. doi:10.2353/ajpath.2009.090351
- Portillo-Esnaola M, Rodríguez-Luna A, Nicolás-Morala J, et al. Formation of Cyclobutane Pyrimidine Dimers after UVA Exposure (Dark-CPDs) Is Inhibited by an Hydrophilic Extract of Polypodium leucotomos. Antioxidants (Basel). 2021;10(12):1961. Published 2021 Dec 7. doi:10.3390/antiox10121961
- Capote R, Alonso-Lebrero JL, García F, Brieva A, Pivel JP, González S. Polypodium leucotomos extract inhibits trans-urocanic acid photoisomerization and photodecomposition. J Photochem Photobiol B. 2006;82(3):173-179. doi:10.1016/j.jphotobiol.2005.11.005
- González S, Pathak MA, Cuevas J, Villarrubia VG, Fitzpatrick TB. Topical or oral administration with an extract of Polypodium leucotomos prevents acute sunburn and psoralen-induced phototoxic reactions as well as depletion of Langerhans cells in human skin. Photodermatol Photoimmunol Photomed. 1997;13(1-2):50-60. doi:10.1111/j.1600-0781.1997.tb00108.x
- Middelkamp-Hup MA, Pathak MA, Parrado C, et al. Oral Polypodium leucotomos extract decreases ultraviolet-induced damage of human skin. J Am Acad Dermatol. 2004;51(6):910-918. doi:10.1016/j.jaad.2004.06.027
Niacinamide
Background
Niacinamide (NAM) is the amide form of niacin (vitamin B3). NAM is distinct from niacin and does not cause flushing. Niacinamide is a precursor for nicotinamide adenine dinucleotide (NAD+), which is an essential coenzyme in cellular energy production. Adequate cellular ATP is essential for DNA synthesis and repair. After UV radiation, a cellular energy crisis occurs which restricts DNA repair. Studies demonstrate that niacinamide supplementation is able to prevent the energy crisis and allows for superior DNA repair thus preventing cell damage and death. Prompt DNA repair also leads to downstream benefits, because DNA damage is a signal for other cascades such as local immunosuppression.
Of note, nicotinamide riboside (NR) and nicotinamide mononucleotide (NMN) are similar structures that show excellent promise for their ability to increase coenzyme NAD+. Currently, human clinical trials for photoprotection and skin cancer study niacinamide specifically, so this is the form included in this blend.
Clinical Features
- Oral NAM reduces the incidence of keratinocyte cancers (including squamous cell and basal cell carcinomas) and actinic keratoses among high-risk immunocompetent patients(1). Studies with immunocompromised transplant patients suggested benefit but failed to reach statistical significance(2). It may be less effective in immunosuppressed patients because the mechanism of action is preservation of skin immunity (which requires immune competence).
- Oral NAM improves skin hydration by preventing transepidermal water loss(3).
- Topical NAM: Niacinamide 0.2% and 5% applied after exposure protected from longwave UVA, UVB, and solar-stimulated UV-induced immunosuppression(4).
- Topical and oral niacinamide prevents UV-induced immune suppression and tumor formation in mice (5, 6).
Dosing
- Oral 500mg twice a day for high-risk patients: Most clinicians base recommendations for high-risk skin cancer patients based on the ONTRAC (1) study results for immunocompetent people. We elected to include 250mg as a starting point which can be supplemented with additional NAM for high-risk patients.
- Protection from immunosuppression is seen in humans at doses of 500mg daily and 1500mg daily(7).
- Topically, 5% concentration is most commonly used in studies(8). It is available 5%-20% over the counter.
Safety
- No major adverse effects are reported, even at higher doses in the grams range.
- A meta-analysis published in Nature Medicine(9) stirred some concern for high-dose niacinamide. It demonstrated that a metabolite of niacinamide (elevated in those with a genetic variant) is associated with an increased risk of cardiovascular disease. The authors proposed that this increase in risk might be offsetting the decrease in risk conferred by an increase in HDL known to result from niacin supplementation. More studies need to be done to determine if the population with this genetic variant should abstain from niacin, but this study does not offset the decades of research we have that does not show increase risk of cardiovascular disease with even high dose niacin/niacinamide. For e.g.
- Renal Disease: For NAM specifically, there appears to be a dose-dependent association between NAM and risk of thrombocytopenia and diarrhea in patients with renal impairment. There has been no report of thrombocytopenia in patients without ESRD.
- Liver Disease: Elevated liver enzymes have been reported with extended release niacin. For NAM, hepatotoxicity has been documented in a case study of NAM administration of >9 g per day and in other reports of doses greater than 3 g daily(12).
- Pediatric population: oral niacin has been studied in the pediatric population for children on hemodialysis. Doses in the range of 100-300mg daily are used and the only side effects included nausea, diarrhea, and flushing. People on hemodialysis have a known higher risk of side effects presumably due to the reliance of niacin on renal clearance(13).
Mechanism of Action:
- Enhances the repair of ultraviolet (UV) radiation-induced DNA damage by mitigating UV-induced energy crisis (3).
- Reduces the cutaneous immunosuppressive effects of UV radiation via upregulation of succinic dehydrogenase, an essential enzyme in cellular respiration, and tumor suppressor protein p53 (4).
- Chen AC, Martin AJ, Choy B, Fernández-Peñas P, Dalziell RA, McKenzie CA, Scolyer RA, Dhillon HM, Vardy JL, Kricker A, St George G, Chinniah N, Halliday GM, Damian DL. A Phase 3 Randomized Trial of Nicotinamide for Skin-Cancer Chemoprevention. N Engl J Med. 2015 Oct 22;373(17):1618-26. doi: 10.1056/NEJMoa1506197. PMID: 26488693.
- Allen NC, Martin AJ, Snaidr VA, Eggins R, Chong AH, Fernandéz-Peñas P, Gin D, Sidhu S, Paddon VL, Banney LA, Lim A, Upjohn E, Schaider H, Ganhewa AD, Nguyen J, McKenzie CA, Prakash S, McLean C, Lochhead A, Ibbetson J, Dettrick A, Landgren A, Allnutt KJ, Allison C, Davenport RB, Mumford BP, Wong B, Stagg B, Tedman A, Gribbin H, Edwards HA, De Rosa N, Stewart T, Doolan BJ, Kok Y, Simpson K, Low ZM, Kovitwanichkanont T, Scolyer RA, Dhillon HM, Vardy JL, Chadban SJ, Bowen DG, Chen AC, Damian DL. Nicotinamide for Skin-Cancer Chemoprevention in Transplant Recipients. N Engl J Med. 2023 Mar 2;388(9):804-812. doi: 10.1056/NEJMoa2203086. PMID: 36856616.
- Snaidr VA, Damian DL, Halliday GM. Nicotinamide for photoprotection and skin cancer chemoprevention: A review of efficacy and safety. Exp Dermatol. 2019;28 Suppl 1:15-22. doi:10.1111/exd.13819
- Sivapirabu G, Yiasemides E, Halliday GM, Park J, Damian DL. Topical nicotinamide modulates cellular energy metabolism and provides broad-spectrum protection against ultraviolet radiation-induced immunosuppression in humans. Br J Dermatol. 2009;161(6):1357-1364. doi:10.1111/j.1365-2133.2009.09244.x
- Gensler HL. Prevention of photoimmunosuppression and photocarcinogenesis by topical nicotinamide. Nutr Cancer. 1997;29(2):157-162. doi:10.1080/01635589709514618
- Gensler HL, Williams T, Huang AC, Jacobson EL. Oral niacin prevents photocarcinogenesis and photoimmunosuppression in mice. Nutr Cancer. 1999;34(1):36-41. doi:10.1207/S15327914NC340105
- Yiasemides E, Sivapirabu G, Halliday GM, Park J, Damian DL. Oral nicotinamide protects against ultravioletradiation-induced immunosuppression in humans. Carcinogenesis. 2009;30(1):101-105. doi:10.1093/carcin/bgn248
- Damian DL, Patterson CR, Stapelberg M, Park J, Barnetson RS, Halliday GM. UV radiation-induced immunosuppression is greater in men and prevented by topical nicotinamide. J Invest Dermatol. 2008;128(2):447-454. doi:10.1038/sj.jid.5701058
- Ferrell M, Wang Z, Anderson JT, et al. A terminal metabolite of niacin promotes vascular inflammation and contributes to cardiovascular disease risk [published correction appears in Nat Med. 2024 Jun;30(6):1791. doi: 10.1038/s41591-024-02899-7]. Nat Med. 2024;30(2):424-434. doi:10.1038/s41591-023-02793-8
- Gale EA, Bingley PJ, Emmett CL, Collier T; European Nicotinamide Diabetes Intervention Trial (ENDIT) Group. European Nicotinamide Diabetes Intervention Trial (ENDIT): a randomised controlled trial of intervention before the onset of type 1 diabetes. Lancet. 2004;363(9413):925-931. doi:10.1016/S0140-6736(04)15786-3
- D'Andrea E, Hey SP, Ramirez CL, Kesselheim AS. Assessment of the Role of Niacin in Managing Cardiovascular Disease Outcomes: A Systematic Review and Meta-analysis. JAMA Netw Open. 2019 Apr 5;2(4):e192224. doi: 10.1001/jamanetworkopen.2019.2224. PMID: 30977858; PMCID: PMC6481429.
- Snaidr VA, Damian DL, Halliday GM. Nicotinamide for photoprotection and skin cancer chemoprevention: A review of efficacy and safety. Exp Dermatol. 2019;28 Suppl 1:15-22. doi:10.1111/exd.13819
- El Borolossy R, El Wakeel LM, El Hakim I, Sabri N. Efficacy and safety of nicotinamide in the management of hyperphosphatemia in pediatric patients on regular hemodialysis. Pediatr Nephrol. 2016;31(2):289-296. doi:10.1007/s00467-015-3208-1
Green tea extract
Background
Green tea extracts derived from Camellia sinensis are abundant in flavonoids called catechins. The four major catechin compounds are (−)-epigallocatechin-3-gallate (EGCG), (−)-epigallocatechin (EGC), (−)-epicatechin-3-gallate (ECG), and (−)-epicatechin (EC). EGCG is the most abundant and extensively studied catechin, and green tea metabolites are known to be bioavailable in the dermis and epidermis of the skin. In vivo human studies and animal models demonstrate green tea catechin’s anti-inflammatory, antioxidant, photo-protective, and chemo-preventative effects after topical application and/or oral ingestion (1).
Clinical Features
- Regular catechin supplementation as low as 540mg per day was found to strengthen the skin’s tolerance against UV radiation induced skin damage (DNA damage) and erythema (increase in MED) in a systematic review and meta-analysis published by Kapoor et al. in 2021.
- Intake of 1402 mg of green tea catechins improves skin structural characteristics such as elasticity, roughness, scaling, density and water balance in women (2).
- Oral administration of green tea polyphenols in mice protects against UV induced non-melanoma skin cancer in terms of tumor incidence and size (3).
Dosing
- ECGC 250-300 mg daily in supplement form
Safety
- Daily intakes equal to or above 800 mg of EGCG per day may increase transaminases according to 2018 European Food Safety Authority (EFSA)(4).
- In a systematic review in 2018, Hu et al.(5) concluded
- National Center for Complementary and Integrative Health (NCCIH) at the National Institute of Health (NIH) notes that it is safe to consume up to 8 cups of green tea daily (6).
- Primary concern is for hepatotoxicity at levels >800mg EGCG daily. Use caution in patients with severe liver disease.
- EGCG may interact with the following medications:
Mechanism of Action
- Anti-inflammatory: selective inhibition of COX-2 and reduces EGFR pathway (1).
- Induces rapid repair of DNA. The DNA repair by GTPs is mediated through the induction of interleukin (IL)-12 which has been shown to have DNA repair ability (8).
- Kapoor MP, Sugita M, Fukuzawa Y, Timm D, Ozeki M, Okubo T. Green Tea Catechin Association with Ultraviolet Radiation-Induced Erythema: A Systematic Review and Meta-Analysis. Molecules. 2021;26(12):3702. Published 2021 Jun 17. doi:10.3390/molecules26123702
- Heinrich U, Moore CE, De Spirt S, Tronnier H, Stahl W. Green tea polyphenols provide photoprotection, increase microcirculation, and modulate skin properties of women. J Nutr. 2011 Jun;141(6):1202-8. doi: 10.3945/jn.110.136465. Epub 2011 Apr 27. PMID: 21525260.
- Mantena SK, Meeran SM, Elmets CA, Katiyar SK. Orally administered green tea polyphenols prevent ultraviolet radiation-induced skin cancer in mice through activation of cytotoxic T cells and inhibition of angiogenesis in tumors. J Nutr. 2005 Dec;135(12):2871-7. doi: 10.1093/jn/135.12.2871. PMID: 16317135.
- EFSA ANS Panel (EFSA Panel on Food Additives and Nutrient Sources added to Food), Younes et al., P. Scientific Opinion on the safety of green tea catechins. EFSA Journal 2018;16(4):5239, 89 pp. https://doi.org/10.2903/j.efsa.2018.5239
- Hu J, Webster D, Cao J, et al. The safety of green tea and green tea extract consumption in adults - Results of a systematic review. Regul Toxicol Pharmacol. 2018;95:412-433. doi:10.1016/j.yrtph.2018.03.019
- National Institute of Health National Center for Complementary and Integrative Health. Green tea.
- Abdelkawy KS, Abdelaziz RM, Abdelmageed AM, et al. Effects of green tea extract on atorvastatin pharmacokinetics in healthy volunteers. Eur J Drug Metab Pharmacokinet. 2020;45(3):351-360. doi:10.1007/s13318-020-00608-6
- Katiyar SK. Green tea prevents non-melanoma skin cancer by enhancing DNA repair. Arch Biochem Biophys. 2011 Apr 15;508(2):152-8. doi: 10.1016/j.abb.2010.11.015. Epub 2010 Nov 19. PMID: 21094124; PMCID: PMC3077767.
- Frasheri L, Schielein MC, Tizek L, Mikschl P, Biedermann T, Zink A. Great green tea ingredient? A narrative literature review on epigallocatechin gallate and its biophysical properties for topical use in dermatology. Phytother Res. 2020 Sep;34(9):2170-2179. doi: 10.1002/ptr.6670. Epub 2020 Mar 18. PMID: 32189392.
Lutein
Background
Lutein is a carotenoid known primarily for its role in eye health, particularly in protecting against age-related macular degeneration. However, its benefits extend beyond eye health to applications in dermatology and skincare.
Lutein is a naturally occurring pigment found in various fruits and vegetables, particularly in green leafy vegetables like spinach and kale, as well as in egg yolks. It belongs to the family of carotenoids, which are potent antioxidants known for their ability to neutralize free radicals and protect cells from oxidative stress.
Clinical Features
- Antioxidant Protection: Lutein is an antioxidant in the skin, scavenging free radicals generated by UV radiation and environmental pollutants. This antioxidant activity helps protect skin cells from oxidative damage, which can lead to premature aging and skin cancer (1,2).
- Blue Light Protection: Blue light triggers melasma and other hyperpigmentation in the skin. The importance of protection from blue light and electronic “light pollution” for skin aesthetics is being increasingly recognized. Lutein is able to absorb, and thus filter out, high-energy blue light. Its absorption peak is in the blue wavelengths of visible light with a maximum absorbance at 446nm. It is also important to note that visible light is responsible for one-third of the free radical formation in the skin after full spectrum irradiation and protection from visible light is therefore an essential piece of a comprehensive skin protection plan.
- Skin Hydration: Some studies suggest that lutein supplementation may improve skin hydration and elasticity, possibly due to its antioxidant properties and ability to support skin barrier function (3).
- Anti-Inflammatory Effects: Lutein exhibits anti-inflammatory properties that can help mitigate skin inflammation and redness, making it potentially beneficial for conditions like acne and rosacea (4).
Dosing
- Studies investigating the effects of lutein on skin health typically use doses ranging from 5 mg to 20 mg per day.
- For example, a study evaluating the effects of lutein on skin hydration and elasticity used a daily dose of 10 mg (3).
Safety
- Digestive Issues: In some cases, high doses of lutein (typically above 20 mg per day) may cause mild gastrointestinal disturbances such as nausea, diarrhea, or stomach cramps.
- Carotenoderma/Skin Discoloration: High doses of carotenoids can lead to reversible yellowing of the skin known as carotenodermia. This is more commonly associated with high doses of beta-carotene (20-50mg/day), another carotenoid, but may occur with lutein as well in very high doses.
- Interactions with Medications: Lutein supplements could potentially interact with medications, particularly those that affect blood clotting or blood thinners. However, specific interactions with lutein are not well-documented compared to other supplements.
- Stahl, W., et al. (1998). Macular pigment: Abundance, bioavailability, and relationship with macular disease. Nutrition Reviews, 56(6), 193-202.
- Palombo, P., et al. (2007). Beneficial long-term effects of combined oral/topical antioxidant treatment with the carotenoids lutein and zeaxanthin on human skin: A double-blind, placebo-controlled study. Skin Pharmacology and Physiology, 20(4), 199-210.
- Grether-Beck, S., et al. (2017). Topical application of lutein-loaded nanocrystals: Influence of formulation parameters on lutein deposition in porcine skin. European Journal of Pharmaceutics and Biopharmaceutics, 119, 315-322.
- Böhm, F., et al. (2014). Lutein suppresses IL-1β-induced inflammation in LSkeratinocytes and reduces inflammation in UV-irradiated skin in mice. Journal of Investigative Dermatology, 134(6), 1450-1457.
Lycopene
Background
Lycopene is a powerful antioxidant belonging to the carotenoid family, primarily found in tomatoes and other red fruits and vegetables. As a micronutrient, lycopene is absorbed in the gut and deposited into light-exposed tissues where it serves to filter light, scavenge free radicals, and neutralize reactive oxygen species (ROS).
Clinical Features
- Lycopene ingestion over 10-12 weeks has been shown to increase minimal erythemal dose (MED) in human clinical trials (1,2). In animal models, it can significantly slow the onset and reduce the incidence, multiplicity, and tumor weights of UVB-induced skin tumors in mice (3).
- Anti-aging: The extended system of conjugated double bonds endows carotenoids like lycopene with powerful antioxidant properties. They are particularly efficient natural scavengers of singlet molecular oxygen. Lycopene was shown to completely inhibit UVA/B induced upregulation of HO1, ICAM1 and MMP1 mRNA in a 2017 study with lycopene-rich tomato paste (4). Protection from UV-induced oxidative stress and preservation of structural extracellular matrix components like collagen protects from premature skin aging.
Dosing
- Studies investigating the effects of lycopene on skin health include dosing in the range of 8 mg to 16 mg per day.
- Human clinical trials demonstrate an increase in minimal erythemal dose after 15mg daily and the equivalent of 16mg/d from tomato paste (2,5).
Safety
- No upper limit of lycopene has been reported in toxicology studies, and both diet and supplements are safe and well-tolerated at doses up to 3000mg per day (6).
- Lycopenemia was the only condition reported due to exorbitant lycopene intake via consuming up to 2L of tomato juice.
- Medication Interactions: Lycopene may have antiplatelet effects and could potentially interact with anticoagulant medications, increasing the risk of bleeding.
- Stahl W, Heinrich U, Aust O, Tronnier H, Sies H. Lycopene-rich products and dietary photoprotection. Photochem Photobiol Sci. 2006;5(2):238-242. doi:10.1039/b505312a
- Stahl, W., et al. (2001). Dietary tomato paste protects against ultraviolet light-induced erythema in humans. The Journal of Nutrition, 131(5), 1449-1451.
- Zhou X, Burke KE, Wang Y, Wei H. Dietary Lycopene Protects SKH-1 Mice Against Ultraviolet B-Induced Photocarcinogenesis. J Drugs Dermatol. 2019 Dec 1;18(12):1244-1254. PMID: 31860213.
- Grether-Beck S, Marini A, Jaenicke T, Stahl W, Krutmann J. Molecular evidence that oral supplementation with lycopene or lutein protects human skin against ultraviolet radiation: results from a double-blinded, placebo-controlled, crossover study. Br J Dermatol. 2017;176(5):1231-1240. doi:10.1111/bjd.15080
- Heinrich, U., et al. (2003). Supplementation with β-carotene or a similar amount of mixed carotenoids protects humans from UV-induced erythema. Journal of Nutrition, 133(1), 98-101.
- Tufail T, Bader Ul Ain H, Noreen S, Ikram A, Arshad MT, Abdullahi MA. Nutritional Benefits of Lycopene and Beta-Carotene: A Comprehensive Overview. Food Sci Nutr. 2024;12(11):8715-8741. Published 2024 Oct 16. doi:10.1002/fsn3.4502
Astaxanthin
Background
Astaxanthin (ASX) is a ketocarotenoid most commonly isolated from the microalgae Haematococcus pluvialis. It has gained attention for its benefits in dermatology and skincare. It is found primarily in marine organisms such as microalgae, salmon, shrimp, and krill, where it serves as a protective agent against oxidative stress. ASX is considered to be one of the most effective carotenoids and has been reported to be approximately 10 times more potent as an antioxidant than beta-carotene, 500 times more potent than alpha-tocopherol, and 6000 times stronger than vitamin C (1).
In dermatology, astaxanthin is valued for its ability to scavenge free radicals and reduce oxidative damage induced by ultraviolet (UV) radiation and other environmental stressors. UV radiation, in particular, is a major cause of skin aging, inflammation, and DNA damage, leading to wrinkles, pigmentation, and skin cancer.
Clinical Features
- Increases minimal erythemal dose (reduced burning) and preserves hydration of the skin following ultraviolet exposure in humans (2).
- Restores moisture content and improves elasticity in human skin (3).
- In mice, astaxanthin protects against UV-induced photoaging. It reduces UV light-induced wrinkle formation and skin thickening, and it increases collagen (4).
Dosing
Oral supplementation doses range from 2 mg to 12 mg daily for skin health benefits, though some studies have used higher doses up to 16 mg or more per day. There is no universally established maximum dose for astaxanthin, but studies have used doses up to 12 mg to 16 mg daily for several months and much higher doses as a single dose.
Safety
Astaxanthin has been studied extensively for its safety profile, and there are no significant documented adverse effects at standard doses (5, 6).
Mechanism of Action
- Antioxidant Protection: Astaxanthin is a potent antioxidant that neutralizes singlet oxygen radicals in the epidermis and dermis generated by UV radiation and environmental stressors (7). Astaxanthin also upregulates endogenous antioxidant enzymes such as superoxide dismutase 2, catalase, and glutathione peroxidase 1 for further sequestration of oxidative stress in UV-irradiated cells (3).
- Anti-Inflammatory Effects: Its amphipathic structure allows ASX to be incorporated into the bilayers of cell membranes where it reduces lipid peroxidation. Supplementation in humans has been shown to lower concentrations of the plasma inflammatory marker CRP and reduce UV-induced inflammatory mediators in HaCaT keratinocytes and fibroblasts (8). In human photoaged skin, supplementation with ATX combined with collagen hydrolysate resulted in increased expression of procollagen type I mRNA and decreased expression of MMP-1 mRNA (9).
- Skin Barrier Function: Chalyk et al. demonstrated systemic antioxidant and skin barrier benefits of astaxanthin in humans (10). In mice, astaxanthin is found to reduce transepidermal water loss and promote production of natural moisturizing factors through stimulation of filaggrin proteolysis (11, 12).
- Adıgüzel E, Ülger TG. A marine-derived antioxidant astaxanthin as a potential neuroprotective and neurotherapeutic agent: A review of its efficacy on neurodegenerative conditions. Eur J Pharmacol. 2024;977:176706. doi:10.1016/j.ejphar.2024.176706
- Ito N, Seki S, Ueda F. 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):817. doi: 10.3390/nu10070817. PMID: 29941810; PMCID: PMC6073124.
- Zhou X, Cao Q, Orfila C, Zhao J, Zhang L. Systematic Review and Meta-Analysis on the Effects of Astaxanthin on Human Skin Ageing. Nutrients. 2021;13(9):2917. Published 2021 Aug 24. doi:10.3390/nu13092917
- Li X, Matsumoto T, Takuwa M, Saeed Ebrahim Shaiku Ali M, Hirabashi T, Kondo H, Fujino H. Protective Effects of Astaxanthin Supplementation against Ultraviolet-Induced Photoaging in Hairless Mice. Biomedicines. 2020 Jan 21;8(2):18. doi: 10.3390/biomedicines8020018. PMID: 31973028; PMCID: PMC7168265.
- Karppi J, Rissanen TH, Nyyssönen K, Kaikkonen J, Olsson AG, Voutilainen S, Salonen JT. Effects of astaxanthin supplementation on lipid peroxidation. Int J Vitam Nutr Res. 2007 Jan;77(1):3-11. doi: 10.1024/0300-9831.77.1.3. PMID: 17685090.
- Adıgüzel E, Ülger TG. A marine-derived antioxidant astaxanthin as a potential neuroprotective and neurotherapeutic agent: A review of its efficacy on neurodegenerative conditions. Eur J Pharmacol. 2024;977:176706. doi:10.1016/j.ejphar.2024.176706
- Yuan, J. P., et al. (2020). Potential health-promoting effects of astaxanthin: A high-value carotenoid mostly from microalgae. Molecular Nutrition & Food Research, 64(10), 1900670.
- Terazawa S, Nakajima H, Shingo M, Niwano T, Imokawa G. Astaxanthin attenuates the UVB-induced secretion of prostaglandin E2 and interleukin-8 in human keratinocytes by interrupting MSK1 phosphorylation in a ROS depletion-independent manner. Exp Dermatol. 2012;21 Suppl 1:11-17. doi:10.1111/j.1600-0625.2012.01496.x
- Zhou X, Cao Q, Orfila C, Zhao J, Zhang L. Systematic Review and Meta-Analysis on the Effects of Astaxanthin on Human Skin Ageing. Nutrients. 2021;13(9):2917. Published 2021 Aug 24. doi:10.3390/nu13092917
- Chalyk, N. E., et al. (2020). Astaxanthin and its metabolites inhibit UV-induced skin inflammation in human keratinocytes by interfering with NF-κB and MAPK pathways. Biochemical Pharmacology, 173, 113728.
- Liu S, Manabe Y, Sugawara T. Oral administration of astaxanthin mitigates chronological skin aging in mice. Biosci Biotechnol Biochem. Published online December 26, 2024. doi:10.1093/bbb/zbae205
- Komatsu T, Sasaki S, Manabe Y, Hirata T, Sugawara T. Preventive effect of dietary astaxanthin on UVA-induced skin photoaging in hairless mice. PLoS One. 2017;12(2):e0171178. Published 2017 Feb 7. doi:10.1371/journal.pone.0171178
Pine bark extract
Background
Pine bark extract has gained attention in dermatology due to its antioxidant and anti-inflammatory properties. Pine bark extract contains a variety of bioactive compounds, including flavonoids, catechins, and procyanidins, which contribute to its therapeutic effects. It has been studied for its potential benefits in promoting skin health, protecting against UV-induced damage, and improving various dermatological conditions.
Clinical Features
- Antioxidant properties protect skin cells from damage caused by UV radiation, pollution, and other environmental factors (1,2).
- Anti-aging: Pine bark extract has been shown to protect from photoaging in human facial skin with beneficial effects on skin elasticity, smoothness, and hydration corresponding with increased gene expression of collagen type I and hyaluronic acid synthase (3,4,5,6).
- UV Protection: Human studies demonstrate an increase in minimal erythemal dose (MED) with follow up keratinocyte cell line studies showing an inhibition of UVR induced NFkB dependent gene expression as a probable mechanism (4).
- UV Protection: In mice, oral pine bark extract protected against UV-induced skin cancer (significant number of animals without tumors and reduction in tumor burden in animals bearing tumors) (7).
- Improvement in melasma (8,9)
- Improvement in psoriasis (10)
Dosing
- Studies investigating the effects of pine bark extract on skin health typically use doses ranging from 50 mg to 250 mg per day. Often 1mg/kg.
Safety
- Human clinical trials do not report significant adverse effects, and pine bark extract is well-tolerated even at higher doses. Minor side effects include mild gastrointestinal symptoms and are transient (3,8,10).
Mechanism of Action
- Antioxidant Activity: Pine bark extract is a potent antioxidant that scavenges free radicals and reduces oxidative stress in the skin. Shown to increase production of hyaluronic acid synthase and collagen and reduce production of elastase, collagenase and MMPs (1).
- Anti-inflammatory Properties: Pine bark extract exhibits anti-inflammatory effects by inhibiting key inflammatory pathways in particular NFkB and results in reduction in inflammatory mediators such as TNF-a, 5-LOX and COX-2 (1,4).
- Weichmann, Franziska & Rohdewald, Peter. (2024). Pycnogenol French maritime pine bark extract in randomized, double-blind, placebo-controlled human clinical studies. Frontiers in Nutrition. 11. 10.3389/fnut.2024.1389374.
- Grether-Beck S, Marini A, Jaenicke T, Krutmann J. French Maritime Pine Bark Extract (Pycnogenol®) Effects on Human Skin: Clinical and Molecular Evidence. Skin Pharmacol Physiol. 2016;29(1):13-7. doi: 10.1159/000441039. Epub 2015 Oct 23. PMID: 26492562.
- Furumura M, Sato N, Kusaba N, Takagaki K, Nakayama J. Oral administration of French maritime pine bark extract (Flavangenol(®)) improves clinical symptoms in photoaged facial skin. Clin Interv Aging. 2012;7:275-286. doi:10.2147/CIA.S33165
- Saliou, C., et al. (2001). Solar ultraviolet-induced erythema in human skin and nuclear factor-κB-dependent gene expression in keratinocytes are modulated by a French maritime pine bark extract. Free Radical Biology and Medicine, 30(2), 154-160.
- Marini A, Grether-Beck S, Jaenicke T, Weber M, Burki C, Formann P, Brenden H, Schonlau F, Krutmann J: Pycnogenol ® effects on skin elasticity and hydration coincide with increased gene expressions of collagen type I and hyaluronic acid synthase in women . Skin Pharmacol Physiol 2012; 25: 86–92.
- Segger D, Schonlau F: Supplementation with Evelle improves skin smoothness and elasticity in a double-blind, placebo-controlled study with 62 women. J Dermatolog Treat 2004;15:222–226.
- Kyriazi M, Yova D, Rallis M, Lima A: Cancer chemopreventive effects of Pinus maritima bark extract on ultraviolet radiation and ultraviolet radiation-7,12-dimethylbenz(a)anthracene induced skin carcinogenesis of hairless mice. Cancer Lett 2006; 237: 234–241.
- Ni Z, Mu Y, Gulati O: Treatment of melasma with Pycnogenol . Phytother Res 2002; 16: 567–571.
- Grether-Beck S, Marini A, Jaenicke T, Krutmann J: An intervention study to evaluate the in vivo cosmetic effects of a dietary supplement (Pycnogenol) in postmenopausal healthy women: additional gene expression studies. 2013.
- Belcaro G, Luzzi R, Hu S, et al. Improvement in signs and symptoms in psoriasis patients with Pycnogenol® supplementation. Panminerva Med. 2014 Mar;56(1):41-8.
Grape seed extract
Background
Grape seed extract (GSE) is derived from the seeds of grapes (Vitis vinifera) and is known for its rich content of antioxidants, primarily proanthocyanidins (oligomeric proanthocyanidins or OPCs), flavonoids, and polyphenols. The most abundant phenolic compounds isolated from grape seed are catechins, epicatechin, and procyanidins (1). These compounds are believed to contribute to various health benefits, including potential applications in dermatology and skincare.
Clinical Features
- UV Protection: Human keratinocyte cell lines treated with proanthocyanidins and grape seed extract show protection from UVB by suppressing oxidant stress, acute inflammation, and cell apoptosis via regulation of MAPK and NF-kB pathways (1,2).
- UV Protection: Mice supplemented with oral proanthocyanidins demonstrated reduction of UVR-induced skin cancer (3,4).
- Improved skin hydration and reduced pigmentation (5).
Dosing:
- Typical doses used in studies range from 100 mg to 400 mg per day.
- Higher doses, up to 600 mg per day, have been used in some clinical trials without significant adverse effects reported.
Safety:
- A study assessed the acute toxicity of grape seed extract in rats and found no significant adverse effects even at high doses, suggesting a wide margin of safety (6,7).
- Human studies have also supported the safety profile of grape seed extract at doses as high as 2500 mg daily. No significant drug interactions have been identified (8).
Mechanism of Action:
- Antioxidant Properties: GSE contains potent antioxidants that scavenge free radicals and reduce oxidative stress in the skin caused by environmental factors such as UV radiation and pollution. Additionally they enhance CAT, SOD, GSH, and GSH-Px activities (9).
- Anti Inflammatory Properties: Oligomeric proanthocyanidins protect against UVB induced damage not only by reduction of intracellular ROS but also by anti-inflammatory effects by regulating MAPK and NF-kB signaling pathways (10,11).
- Shi J, Yu J, Pohorly JE, Kakuda Y. Polyphenolics in grape seeds-biochemistry and functionality. J Med Food. 2003 Winter;6(4):291-9. doi: 10.1089/109662003772519831. PMID: 14977436.
- Perde-Schrepler M, Chereches G, Brie I, Tatomir C, Postescu ID, Soran L, Filip A. Grape seed extract as photochemopreventive agent against UVB-induced skin cancer. J Photochem Photobiol B. 2013 Jan 5;118:16-21. doi: 10.1016/j.jphotobiol.2012.10.008. Epub 2012 Nov 3. PMID: 23178081.
- Katiyar SK, Pal HC, Prasad R. Dietary proanthocyanidins prevent ultraviolet radiation-induced non-melanoma skin cancer through enhanced repair of damaged DNA-dependent activation of immune sensitivity. Semin Cancer Biol. 2017 Oct;46:138-145. doi: 10.1016/j.semcancer.2017.04.003. Epub 2017 Apr 12. PMID: 28412456.
- Mittal A, Elmets CA, Katiyar SK. Dietary feeding of proanthocyanidins from grape seeds prevents photocarcinogenesis in SKH-1 hairless mice: relationship to decreased fat and lipid peroxidation. Carcinogenesis. 2003 Aug;24(8):1379-88. doi: 10.1093/carcin/bgg095. Epub 2003 Jun 5. PMID: 12807737.
- Tsuchiya T, Fukui Y, Izumi R, Numano K, Zeida M. Effects of oligomeric proanthocyanidins (OPCs) of red wine to improve skin whitening and moisturizing in healthy women - a placebo-controlled randomized double-blind parallel group comparative study. Eur Rev Med Pharmacol Sci. 2020;24(3):1571-1584. doi:10.26355/eurrev_202002_20215.
- Charradi K, Mahmoudi M, Bedhiafi T, et al. Safety evaluation, anti-oxidative and anti-inflammatory effects of subchronically dietary supplemented high dosing grape seed powder (GSP) to healthy rat. Biomed Pharmacother. 2018;107:534-546. doi:10.1016/j.biopha.2018.08.031
- Bagchi, D., et al. (2002). Acute and chronic toxicity studies of a novel grape seed proanthocyanidin extract. Food and Chemical Toxicology, 40(5), 599-607.
- Sano A. Safety assessment of 4-week oral intake of proanthocyanidin-rich grape seed extract in healthy subjects. Food Chem Toxicol. 2017;108(Pt B):519-523. doi:10.1016/j.fct.2016.11.021
- Lai, R., Xian, D., Xiong, X., Yang, L., Song, J., & Zhong, J. (2018). Proanthocyanidins: novel treatment for psoriasis that reduces oxidative stress and modulates Th17 and Treg cells. Redox Report, 23(1), 130–135.
- Shi X, Shang F, Zhang Y, Wang R, Jia Y, Li K. Persimmon oligomeric proanthocyanidins alleviate ultraviolet B-induced skin damage by regulating oxidative stress and inflammatory responses. Free Radic Res. 2020 Oct;54(10):765-776. doi: 10.1080/10715762.2020.1843651. Epub 2020 Nov 9. PMID: 33108915.
- Sharma SD, Meeran SM, Katiyar SK. Dietary grape seed proanthocyanidins inhibit UVB-induced oxidative stress and activation of mitogen-activated protein kinases and nuclear factor- B signaling in in vivo SKH-1 hairless mice. Mol Cancer Ther. 2007;6(3):995–1005.