|Grade||Level of Evidence|
|A||Multiple double-blind, controlled clinical trials.|
|B||1 double-blind, controlled clinical trial.|
|C||At least 1 controlled or comparative clinical trial.|
|D||Uncontrolled, observational, animal or in-vitro studies only.|
|Grade||Effect||Size of Effect||Comments|
Acts as a UV filter by absorbing UV radiation in the range between 300-350 nm. 2% retinyl palmitate is as effective as an SPF 20 sunscreen in inhibiting sunburn erythema and thymine dimer formation.
Improves wrinkles around the eyes and possibly on the face and neck.
Increases the thickness of the epidermis in mouse and guinea pig skin.
Prevents the reduction in superoxide dismutase activity by UV light.
Looking to buy skin care products containing Retinyl Palmitate?
Buy from Amazon.com..
Table of contents:
- 1. Sources
- 2. Bioavailability
- 3. Effects on the skin
- 4. Side Effects
1.1 In the skin
Retinyl esters are the major storage forms of vitamin A in animal tissues, including those of humans. In human skin, retinyl esters account for >70% of the endogenous vitamin A. Of these retinyl palmitate, an ester of retinol and palmitic acid, is the predominant component.
The epidermis contains approximately 3.5 times more retinyl esters (including retinyl palmitate) than the dermis, but sunlight induces a rapid degradation of epidermal retinyl esters without significantly reducing dermal retinyl esters. In an experiment on cultured keratinocytes, 80% of retinyl esters disappeared upon irradiation.
The amount of retinyl palmitate in the skin may decline with age. In an experiment on female mice, age-related effects were observed in the stratum corneum, epidermis and dermis, with the level of retinyl palmitate being the highest in the epidermis of 20-week-old mice, and decreasing by about 4-fold at 60-68-weeks of age.
1.2 In cosmetic products
Retinyl palmitate is widely used in cosmetics. In 2008, there were 1778 cosmetic products containing retinyl palmitate in the US FDA's Voluntary Cosmetic Registration Program, compared to 160 products containing retinol, 28 products containing retinyl acetate and 3 products containing retinoic acid. The concentration of retinyl palmitate in cosmetic products ranges from 0.1% to 10%, but is generally less than or equal to 1%.
2.1 Topical administration
Retinyl palmitate is more thermally stable than retinol, and is therefore frequently used as a retinoid in cosmetic products. It is however more photochemically labile than retinol, which is problematic. The addition of sunscreens such as butyl methoxy dibenzoylmethane and antioxidants such as vitamin C, vitamin E and butyl hydroxytoluene (BHT) helps increase the stability of retinyl palmitate in cosmetic formulations. Other details of the formulation also matter -- one formulation containing combinations of retinyl palmitate, tocopherol acetate and α-tocopherol had a shelf life of just 77 days, but a different formulation containing retinyl palmitate, ascorbyl tetraisopalmitate and tocopheryl acetate had a much better shelf life of 120 days. The difference was thought to be due to the high levels of water in the first formulation, which enhances hydrolysis reactions, versus the second formulation that contains ethylhexyl ethylhexanoate, a high molecular weight emollient that reduces the electrical conductivity of the medium and consequently the hydrolysis of retinyl palmitate.
The percutaneous absorption of retinyl palmitate is well-established; it diffuses rapidly into the stratum corneum and epidermis after application. In one study, 18% of topically applied retinyl palmitate was absorbed into human skin from an acetone vehicle. Interestingly, the permeation and deposition of retinyl palmitate can be enhanced by the combined use of pectin and ascorbyl palmitate, which increases the amount of retinyl palmitate deposited in the epidermis substantially, presumably through their antioxidative effect. The addition of glycolic acid on the other hand may not increase the total amount of retinyl palmitate that penetrates into the skin, although it seems to promote a faster permeation.
Many drug delivery systems have been developed to further improve the dermal and transdermal release of retinyl palmitate, including hydrogels, micelles, microcapsules, liposomes liquid crystalline systems and nanoparticles. Retinyl palmitate can also be used as the core of polymeric nanocapsules to deliver retinyl palmitate and other actives into deep layers of the skin.
To be pharmalogically active, retinyl palmitate must be enzymatically converted in the skin to retinol by cleavage of the ester linkage and subsequently converted to tretinoin via oxidative processes. There is evidence that this does happen; in an experiment on human skin, 44% of absorbed retinyl palmitate was hydrolyzed by esterases in the skin to retinol. Although no other metabolites were detected, retinol is known to be metabolized to tretinoin in small amounts in the epidermis and dermis. Some of the absorbed retinyl palmitate is likely stored in the skin, as topical application of retinyl palmitate has been shown to alter the physiological levels of retinoids in mice skin and human skin explants. In fact, cultured human fibroblasts have demonstrated a remarkable uptake and storage of retinyl palmitate in vitro.
Because of the multiple conversion steps, higher concentrations of retinyl palmitate as compared to retinol or retinal are required in cosmetic formulations to produce similar cellular and molecular changes in the skin.
2.2 Oral administration
Oral supplementation with retinyl palmitate raises the circulating serum levels of retinoic acid and retinol. On average, for every 10,000 IU of retinyl palmitate/day, the serum retinol concentration increases by 13 µg/l after 3 months and 12 µg/l after 6 months of supplementation (a 2% increase). However, the concentrations of retinol and retinyl palmitate in the skin does not change significantly compared to controls even after long periods of supplementation.
3. Effects on the skin
Retinyl esters strongly absorb UV radiation between 300-350 nm, a wavelength range received from the sun at earth level. In vitro, retinyl palmitate displayed a UV filtering capacity similar to that of the sunscreen octylmethoxycinnamate. In vivo, 2% retinyl palmitate prevented the formation of thymine dimers in hairless mice, and was as effective as an SPF 20 commercial sunscreen in inhibiting sunburn erythema and thymine dimer formation in human buttock skin.
Although the natural concentrations of epidermal retinyl esters are too low to exert a measurable sunscreen effect, retinyl esters can be easily loaded to the skin by topical application. Hence, retinyl palmitate can be used as a supplement in cosmetic formulations containing UV filters. It does not protect the skin when applied after UV exposure, however.
3.2 Age-related improvements
Topical retinyl palmitate alters skin composition, morphometry and histology. In mouse skin 0.1-5% retinyl palmitate increased the thickness of the epidermis and caused an accumulation of collagen within the dermis. In guinea pig skin 0.5% retinyl palmitate also led to a thickening of the epidermis and improved skin hydration when combined with 4.2% glycolic acid.
Retinyl palmitate is also known to ease wrinkles. 30 days of treatment with 1% retinyl palmitate in lamellar liquid crystalline systems significantly reduced the percentage areas with wrinkle traces of the eyes of 30 volunteers. 2 studies have also shown that nanoparticles loaded with retinyl palmitate have an anti-wrinkle effect. Because retinyl palmitate-loaded nanoparticles prevented the degradation of elastic fibres and the reduction in superoxide dismutase activity by UV irradiation, it has been hypothesized that retinyl palmitate exerts an antioxidative effect by protecting superoxide dismutase from UV irradiation, preventing the loss of elastin and ultimately resulting in its anti-wrinkle effect.
A few commercially available products containing retinyl palmitate have demonstrated their efficacy in treating aged skin. In a randomized, controlled and single-blinded clinical study, an oil-based moisturizer containing retinyl palmitate and antioxidants (Bio-Oil) was tested for its effects on improving photoaged skin on the face, neck, décolletage, arms and lower legs. 73 women with mild-to-moderate photodamage were randomly assigned to the treatment or no-treatment group, with those in the treatment group instructed to use the moisturizer twice daily on the facial and body skin sites. After 12 weeks, clinical grading revealed significant improvements in overall appearance, fine lines, coarse wrinkles, mottled pigmentation, uneven skin tone, visual and tactile roughness, firm appearance and clarity of the face and neck in women who had used the moisturizer compared to those who had not. There were also significant improvements in overall appearance, crepey texture, dryness/scaling, visual roughness/smoothness, and tactile roughness/smoothness on the décolletage, arms and lower legs of women in the treatment group versus those in the no-treatment group.
In addition, an antiaging product by The Boots Company (possibly the forerunner of the Boots No7 Protect & Perfect Intense Beauty Serum) induced partial repair of photoaged human skin in a 12-day patch test of the forearm, increasing the deposition of fibrillin-1 and procollagen I in the papillary dermis. Retinyl palmitate was present only at a low concentration (0.2%) in the formulation however, and may not have contributed to these positive changes.
3.3 Other effects and uses
Alterations of the extracellular matrix is thought to be one factor involved in the etiology of cellulite. Hence, retinyl palmitate should aid in the treatment of cellulite in theory, but a study on the use of intense pulsed light (IPL) therapy with a retinyl palmitate cream did not find conclusive evidence that retinyl palmitate augments the cosmetic improvement of cellulite.
In another study, retinyl palmitate was included in an ointment used to re-epithelialize the skin following fractional skin resurfacing with a carbon dioxide laser, though its effect in this respect was not measured.
4. Side Effects
4.1 Low risk of systemic toxicity
Although the application of retinyl palmitate to the relatively permeable skin of newborn rats led to significantly higher concentrations of retinyl palmitate and retinol in the lungs and liver, retinyl palmitate does not appear to penetrate well through the skin of adult rats, guinea pigs or humans, indicating only a small risk of systemic exposure. For instance, repeated topical treatment with 0.55% retinyl palmitate on large swathes of the body for 21 days did not alter plasma concentrations of retinol, retinyl esters or retinoic acids in a study on 14 women of child-bearing age.
Retinyl palmitate is included in the US FDA's list of nutrients or dietary supplements that are Generally Recognized as Safe (GRAS). Although chronic retinyl palmitate supplementation induced oxidative stress, mitochondrial impairment and altered behaviour in rats as well as osteotoxicity in mice, oral doses of retinyl palmitate up to 75,000 IU/day for a year has been proven to be safe and efficacious in humans. Single oral doses of up to 30,000 IU/day did not result in any systemic adverse events in adult women either.
4.2 Adverse skin reactions
Topical retinyl palmitate amounting to a total of approximately 30,000 IU/day for 21 days followed by single oral doses of 10,000 IU or 30,000 IU retinyl palmitate has been observed to lead to transient, mild local irritation reactions on the treatment sites in adult women.
Oral administration of 300,000 IU retinyl palmitate daily for 12 months or more as an adjuvant treatment for resected stage I lung cancer also frequently resulted in skin dryness and desquamation in many patients (60% of those treated), with other rarer symptoms such as dyspepsia, headache, nosebleeds and mild hair loss occurring in less than 10% of patients. Fortunately, most of the latter were self-terminating, and overall high-dose retinyl palmitate was considered a safe and well-tolerated treatment in this patient group.
A moisturizer containing 0.1% retinyl palmitate applied to the shaved backs of albino rabbits daily for 4 days led to only slight dermal irritation, but a body lotion containing 0.1% retinyl palmitate applied in the same way caused the development of erythema and edema within 48 hours. These persisted for at least 7 days, resulting in skin dehydration and desquamation.
Dermal irritation and sensitization studies on humans using patch tests concluded that a 1% retinyl palmitate-containing moisturizer was most likely not a primary skin irritant, but may be a sensitizing agent, and that a body lotion containing 0.1% retinyl palmitate was neither a strong irritant nor a strong contact sensitizer.
4.3 Reproductive and developmental toxicity
Excessive intake of retinyl palmitate during pregnancy may lead to maternal toxicity and adverse effects for the developing offspring. The feeding of 2,500-25,000 IU/kg of retinyl palmitate to female rats during gestation and lactation has been shown to induce oxidative stress and redox modulation in both the mothers and their pups, and mice administered 10,000-15,000 IU/kg retinyl palmitate on different days of pregnancy led to malformations in the forelimbs and hindlimbs of the offspring. There have not yet been any studies conducted on the effects of retinyl palmitate supplementation in pregnant women however.
4.4 Possible tumour promotion
The photocarcinogenicity of retinyl palmitate is controversial. There is some indication that retinyl palmitate may potentiate the damaging effects of UVA exposure, as treating mouse lymphoma cells with 1 to 25 µg/ml retinyl palmitate or its photodecomposition products in the presence of UVA light has been shown to induce mutations via a clastogenic mode of action. Photoirradiation of retinyl palmitate and anhydroretinol, one of its major photodecomposition products, is also known to generate reactive oxygen species that can mediate the induction of lipid peroxidation. Similarly, in human skin Jurkat T-cells illumination with UVA + visible light in the presence of retinyl palmitate or its photodecomposition products at concentrations of 100 µM and greater resulted in DNA fragmentation and increased cell death. Retinyl palmitate also appears to have a synergistic effect on the phototoxicity of cosmetic formulations containing avobenzone, a commonly used sunscreen ingredient. However, no overt cytotoxicity was seen in another study where Chinese hamster ovary cells were treated with retinyl palmitate under pre-irradiation or simultaneous irradiation conditions, raising the question of whether the previously reported photogenotoxic effects are due to the different test conditions used. It has also been noted that caution should be exercised in extrapolating the relevance of the findings of such in vitro studies to humans, since these studies do not take into account the complex antioxidant network in human skin.
A few studies have also investigated the photocarcinogenicity of retinyl palmitate in vivo. One revealed that when 0.05% retinyl palmitate in an oil-in-water cream was applied to the backs of hairless mice, it significantly decreased the the number of apoptotic cells as well as the formation of thymine dimers in the epidermis following acute UVB exposure. The National Toxicology Program has also conducted a 1-year study was to investigate the effects of topically applied skin cream containing retinyl palmitate on the photocarcinogenicity of simulated solar light or UV light in hairless mice. Although this study concluded that retinyl palmitate enhanced the photocarcinogenicity activity of SSL and UVB in hairless mice, its findings are considered to be seriously compromised by the effects of the control cream used as the vehicle. This is because the control cream alone caused substantial adverse effects in the control mice exposed to simulated sunlight, UVA, or UVB, as indicated by markedly reduced survivability and in-life skin lesion onset and elevated in-life skin lesion incidence and multiplicity, and is therefore a major confounding factor.
On the other hand, ingestion of retinyl palmitate may lower cancer risk. Female rats on a retinyl palmitate-enriched diet had reduced mammary cancer multiplicity induced by 1-methyl-1-nitrosourea, an animal carcinogen. 2 studies on mice likewise demonstrated that dietary supplementation with retinyl palmitate or retinyl palmitate + the carotenoid canthaxanthin led to decreases in the tumour burden induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) and UV irradiation, respectively. This effect may be due to a heightened tumoricidal capacity of macrophages in mice administered dietary retinyl palmitate.
In humans, daliy oral administration of retinyl palmitate was effective in reducing the number of new primary tumours in the lungs of patients patients cured of early-stage lung cancer, but oral retinyl palmitate alone or plus β-carotene was not effective in reducing the long-term risk of oral cancer.
- Ribaya-Mercado JD, et. al. High concentrations of vitamin A esters circulate primarily as retinyl stearate and are stored primarily as retinyl palmitate in ferret tissues. J Am Coll Nutr. (1994)
- Tanumihardjo SA, et. al. Retinyl ester (vitamin A ester) and carotenoid composition in human liver. Int J Vitam Nutr Res. (1990)
- O'Byrne SM, Blaner WS. Retinol and retinyl esters: biochemistry and physiology. J Lipid Res. (2013)
- Yan J, et. al. Levels of retinyl palmitate and retinol in the skin of SKH-1 mice topically treated with retinyl palmitate and concomitant exposure to simulated solar light for thirteen weeks. Toxicol Ind Health. (2007)
- Yan J, et. al. Levels of retinyl palmitate and retinol in stratum corneum, epidermis and dermis of SKH-1 mice. Toxicol Ind Health. (2006)
- Tang G, et. al. Epidermis and serum protect retinol but not retinyl esters from sunlight-induced photodegradation. Photodermatol Photoimmunol Photomed. (1994)
- Hubinger JC. Determination of retinol, retinyl palmitate, and retinoic acid in consumer cosmetic products. J Cosmet Sci. (2009)
- Natl Toxicol Program Tech Rep Ser. Photocarcinogenesis study of retinoic acid and retinyl palmitate in SKH-1 mice (Simulated Solar Light and Topical Application Study). National Toxicology Program. (2012)
- Idson B. Vitamins in cosmetics, an update. I. Overview and vitamin A. Drug Cosmet Ind. (1990)
- Ihara H, et. al. Esterification makes retinol more labile to photolysis. J Nutr Sci Vitaminol (Tokyo). (1999)
- Carlotti ME, Rossatto V, Gallarate M. Vitamin A and vitamin A palmitate stability over time and under UVA and UVB radiation. Int J Pharm. (2002)
- Moyano MA, Segall A. Vitamin A palmitate and α-lipoic acid stability in o/w emulsions for cosmetic application. J Cosmet Sci. (2011)
- Ro J, et. al. Anti-oxidative activity of pectin and its stabilizing effect on retinyl palmitate. Korean J Physiol Pharmacol. (2013)
- Guaratini T, Gianeti MD, Campos PM. Stability of cosmetic formulations containing esters of vitamins E and A: chemical and physical aspects. Int J Pharm. (2006)
- Gianeti MD, et. al. Benefits of combinations of vitamin A, C and E derivatives in the stability of cosmetic formulations. Molecules. (2012)
- Yan J, et. al. Levels of retinyl palmitate and retinol in the stratum corneum, epidermis, and dermis of female SKH-1 mice topically treated with retinyl palmitate. Toxicol Ind Health. (2006)
- Antille C, et. al. Penetration and metabolism of topical retinoids in ex vivo organ-cultured full-thickness human skin explants. Skin Pharmacol Physiol. (2004)
- Boehnlein J, et. al. Characterization of esterase and alcohol dehydrogenase activity in skin. Metabolism of retinyl palmitate to retinol (vitamin A) during percutaneous absorption. Pharm Res. (1994)
- Suh DC, et. al. Enhanced In Vitro Skin Deposition Properties of Retinyl Palmitate through Its Stabilization by Pectin. Biomol Ther (Seoul). (2014)
- Leonardi GR, Maia Campos P. Influence of glycolic acid as a component of different formulations on skin penetration by vitamin A palmitate. J Soc Cosmet Chem. (1998)
- Carlotti ME, et. al. Vitamin A palmitate photostability and stability over time. J Cosmet Sci. (2004)
- Luppi B, et. al. Poly(vinylalcohol-co-vinyloleate) for the preparation of micelles enhancing retinyl palmitate transcutaneous permeation. Drug Deliv. (2002)
- Chorilli M, et. al. Structural characterization and in vivo evaluation of retinyl palmitate in non-ionic lamellar liquid crystalline system. Colloids Surf B Biointerfaces. (2011)
- Oliveira MB, et. al. Topical application of retinyl palmitate-loaded nanotechnology-based drug delivery systems for the treatment of skin aging. Biomed Res Int. (2014)
- Jenning V, et. al. Vitamin A loaded solid lipid nanoparticles for topical use: occlusive properties and drug targeting to the upper skin. Eur J Pharm Biopharm. (2000)
- Felippi CC, et. al. Safety and efficacy of antioxidants-loaded nanoparticles for an anti-aging application. J Biomed Nanotechnol. (2012)
- Jeon HS, et. al. A retinyl palmitate-loaded solid lipid nanoparticle system: effect of surface modification with dicetyl phosphate on skin permeation in vitro and anti-wrinkle effect in vivo. Int J Pharm. (2013)
- Teixeira Z, et. al. Retinyl palmitate polymeric nanocapsules as carriers of bioactives. J Colloid Interface Sci. (2012)
- Teixeira Z, et. al. Retinyl palmitate flexible polymeric nanocapsules: characterization and permeation studies. Colloids Surf B Biointerfaces. (2010)
- Bailly J, et. al. In vitro metabolism by human skin and fibroblasts of retinol, retinal and retinoic acid. Exp Dermatol. (1998)
- Körner T, Rath FW, Schmidt H. The ability of cultivated human skin fibroblasts to store vitamin A. A contribution to the cytogenesis of the Ito cells of the liver. Exp Pathol. (1988)
- Duell EA, Kang S, Voorhees JJ. Unoccluded retinol penetrates human skin in vivo more effectively than unoccluded retinyl palmitate or retinoic acid. J Invest Dermatol. (1997)
- Sedjo RL, et. al. Circulating endogenous retinoic acid concentrations among participants enrolled in a randomized placebo-controlled clinical trial of retinyl palmitate. Cancer Epidemiol Biomarkers Prev. (2004)
- Wald NJ, et. al. The effect of vitamin A supplementation on serum retinol and retinol binding protein levels. Cancer Lett. (1985)
- Alberts DS, et. al. Pharmacokinetics and metabolism of retinol administered at a chemopreventive level to normal subjects. Cancer Detect Prev. (1988)
- Antille C, et. al. Vitamin A exerts a photoprotective action in skin by absorbing ultraviolet B radiation. J Invest Dermatol. (2003)
- Sorg O, et. al. Proposed mechanisms of action for retinoid derivatives in the treatment of skin aging. J Cosmet Dermatol. (2005)
- Benevenuto CG, et. al. Influence of the photostabilizer in the photoprotective effects of a formulation containing UV-filters and vitamin A. Photochem Photobiol. (2010)
- Park HM, et. al. Direct Analysis in Real Time Mass Spectrometry (DART-MS) Analysis of Skin Metabolome Changes in the Ultraviolet B-Induced Mice. Biomol Ther (Seoul). (2013)
- Counts DF, et. al. The effect of retinyl palmitate on skin composition and morphometry. J Soc Cosmet Chem. (1988)
- Maia Campos PM, et. al. Histopathological, morphometric, and stereologic studies of dermocosmetic skin formulations containing vitamin A and\/or glycolic acid. J Soc Cosmet Chem. (1999)
- Rawlings AV, et. al. The effect of a vitamin A palmitate and antioxidant-containing oil-based moisturizer on photodamaged skin of several body sites. J Cosmet Dermatol. (2013)
- Watson RE, et. al. Repair of photoaged dermal matrix by topical application of a cosmetic 'antiageing' product. Br J Dermatol. (2008)
- Dupont E, et. al. An integral topical gel for cellulite reduction: results from a double-blind, randomized, placebo-controlled evaluation of efficacy. Clin Cosmet Investig Dermatol. (2014)
- Fink JS, et. al. Use of intense pulsed light and a retinyl-based cream as a potential treatment for cellulite: a pilot study. J Cosmet Dermatol. (2006)
- Trelles MA, Shohat M, Urdiales F. Safe and effective one-session fractional skin resurfacing using a carbon dioxide laser device in super-pulse mode: a clinical and histologic study. Aesthetic Plast Surg. (2011)
- Ashmeade TL, et. al. Transcutaneous absorption of vitamin A in newborn rats. Biol Neonate. (2000)
- Nohynek GJ, et. al. Repeated topical treatment, in contrast to single oral doses, with Vitamin A-containing preparations does not affect plasma concentrations of retinol, retinyl esters or retinoic acids in female subjects of child-bearing age. Toxicol Lett. (2006)
- de Oliveira MR, Moreira JC. Acute and chronic vitamin A supplementation at therapeutic doses induces oxidative stress in submitochondrial particles isolated from cerebral cortex and cerebellum of adult rats. Toxicol Lett. (2007)
- de Oliveira MR, et. al. Short-term vitamin A supplementation at therapeutic doses induces a pro-oxidative state in the hepatic environment and facilitates calcium-ion-induced oxidative stress in rat liver mitochondria independently from permeability transition pore formation : detrimental effects of vitamin A supplementation on rat liver redox and bioenergetic states homeostasis. Cell Biol Toxicol. (2009)
- da Rocha RF, et. al. Long-term vitamin A supplementation at therapeutic doses induces mitochondrial electrons transfer chain (METC) impairment and increased mitochondrial membrane-enriched fraction (MMEF) 3-nitrotyrosine on rat heart. Free Radic Res. (2010)
- Forsyth KS, Watson RR, Gensler HL. Osteotoxicity after chronic dietary administration of 13-cis-retinoic acid, retinyl palmitate or selenium in mice exposed to tumor initiation and promotion. Life Sci. (1989)
- Alberts D, et. al. Safety and efficacy of dose-intensive oral vitamin A in subjects with sun-damaged skin. Clin Cancer Res. (2004)
- Hartmann S, et. al. Exposure to retinyl esters, retinol, and retinoic acids in non-pregnant women following increasing single and repeated oral doses of vitamin A. Ann Nutr Metab. (2005)
- Pastorino U, et. al. Safety of high-dose vitamin A. Randomized trial on lung cancer chemoprevention. Oncology. (1991)
- Cosmetic Ingredient Review Expert Panel. Final Report on the Safety Assessment of Retinyl Palmitate and Retinol. Int J Toxicol. (1987)
- Schnorr CE, et. al. The effects of vitamin A supplementation to rats during gestation and lactation upon redox parameters: increased oxidative stress and redox modulation in mothers and their offspring. Food Chem Toxicol. (2011)
- Schnorr CE, et. al. Vitamin A supplementation in rats under pregnancy and nursing induces behavioral changes and oxidative stress upon striatum and hippocampus of dams and their offspring. Brain Res. (2011)
- Rezaei N, Hashemi Soteh MB, Rahimi F. Effects of limited doses of retinyl palmitate at the critical time of limb morphogenesis in mouse embryos. Indian J Exp Biol. (2009)
- Mei N, et. al. Photomutagenicity of retinyl palmitate by ultraviolet a irradiation in mouse lymphoma cells. Toxicol Sci. (2005)
- Mei N, et. al. Photomutagenicity of Anhydroretinol and 5,6-Epoxyretinyl Palmitate in Mouse Lymphoma Cells. Chem Res Toxicol. (2006)
- Xia Q, et. al. Photoirradiation of retinyl palmitate in ethanol with ultraviolet light--formation of photodecomposition products, reactive oxygen species, and lipid peroxides. Int J Environ Res Public Health. (2006)
- Yin JJ, Xia Q, Fu PP. UVA photoirradiation of anhydroretinol--formation of singlet oxygen and superoxide. Toxicol Ind Health. (2007)
- Xia Q, et. al. UVA photoirradiation of retinyl palmitate--formation of singlet oxygen and superoxide, and their role in induction of lipid peroxidation. Toxicol Lett. (2006)
- Cherng SH, et. al. Photodecomposition of retinyl palmitate in ethanol by UVA light-formation of photodecomposition products, reactive oxygen species, and lipid peroxides. Chem Res Toxicol. (2005)
- Yan J, et. al. Photo-induced DNA damage and photocytotoxicity of retinyl palmitate and its photodecomposition products. Toxicol Ind Health. (2005)
- Gaspar LR, et. al. Skin phototoxicity of cosmetic formulations containing photounstable and photostable UV-filters and vitamin A palmitate. Toxicol In Vitro. (2013)
- Dufour EK, et. al. Retinyl palmitate is non-genotoxic in Chinese hamster ovary cells in the dark or after pre-irradiation or simultaneous irradiation with UV light. Mutat Res. (2009)
- Mei N, et. al. UVA-induced photomutagenicity of retinyl palmitate. Mutat Res. (2009)
- Burnett ME, Wang SQ. Current sunscreen controversies: a critical review. Photodermatol Photoimmunol Photomed. (2011)
- Sorg O, et. al. Spectral properties of topical retinoids prevent DNA damage and apoptosis after acute UV-B exposure in hairless mice. Photochem Photobiol. (2005)
- McDaniel SM, et. al. Whole-food sources of vitamin A more effectively inhibit female rat sexual maturation, mammary gland development, and mammary carcinogenesis than retinyl palmitate. J Nutr. (2007)
- Gensler HL, et. al. Effects of dietary retinyl palmitate or 13-cis-retinoic acid on the promotion of tumors in mouse skin. Cancer Res. (1987)
- Gensler HL, Aickin M, Peng YM. Cumulative reduction of primary skin tumor growth in UV-irradiated mice by the combination of retinyl palmitate and canthaxanthin. Cancer Lett. (1990)
- Watson RR, Moriguchi S, Gensler HL. Effects of dietary retinyl palmitate and selenium on tumoricidal capacity of macrophages in mice undergoing tumor promotion. Cancer Lett. (1987)
- Pastorino U, et. al. Adjuvant treatment of stage I lung cancer with high-dose vitamin A. J Clin Oncol. (1993)
- Papadimitrakopoulou VA, et. al. Randomized trial of 13-cis retinoic acid compared with retinyl palmitate with or without beta-carotene in oral premalignancy. J Clin Oncol. (2009)