vehicle-controlled trial, 0.1% stabilized retinol outperformed vehicle at ameliorating all parameters aging including cheek wrinkles, crow’s feet, under-eye wrinkles, discrete pigmentation, mottled pigmentation, and overall skin tone from weeks 24 through the end of the 52-week study (Figure 5). Retinol treated patients experienced a 44% improvement in crow’s feet and 84% improvement in pigmentation over baseline at the end of the study. Over 50% of the patients treated with retinol experience a 2+ grade improvement in many aging skin parameters. This retinol formulation was well tolerated with no adverse events reported by any of the 62 subjects who participated in the study. Biopsies were performed on 12 subjects to address the question of whether the skin remains responsive to topical retinol over an extended period of time. Retinol-treated photoaged skin showed an increased expression of type 1 procollagen at 52 weeks, indicating long-term benefits of retinol on collagen production (Figure 6). Ki67 staining in basal keratinocytes, an indicator of epidermal proliferation, was increased in the retinol-treated group at the end of the study. Expression of hyaluronan both in the dermis and viable layers of the epidermis was also increased compared to vehicle control. This study indicates that long-term use of retinol induces biological responses that improve the appearance of photoaged skin and that the skin remains responsive to topical retinoids even with prolonged use.
The evolution of cosmetic retinols has afforded consumers effective over the counter solutions to address a variety of cosmetic concerns. The data presented here support the notion that retinol-containing cosmeceuticals are not only effective alternatives to retinoic acid but may actually be preferrable since they are more well tolerated and readily available. While some products contain only pure retinol, others contain additional ingredients that provide skin benefits. Topical retinols are inherently well tolerated but some formulations include ingredients like bisabalol or glycerin that reduce the possibility of irritation and dryness. Dermatologists need to familiarize themselves with the nuances of retinols so they can best advise their patients on proper product selection.
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6. Rittie L and Fisher GJ. Natural and sun-induced aging of human skin. Cold Springs Harb Perspect Med. 2015:5:a015370.
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8. Kligman LG, Duo CH, Kligman AM. Topical tretinoin enhances repair of ultraviolet damaged dermal connective tissue. Connect Tissue Res. 1984;12(2):139-150.
9. Cordero AJ. La vitamina a acida en la piel senile. Actualiz Terapeut Dermatologica. 1983;6:49-54.
10. Kligman LH and Kligman AM. The nature of photoaging; Its prevention and repair. Photodermatol. 1986;3:215-227.
11. Weiss JS, Ellis CN, Headington JT et al. Topical tretinoin improves photoaged skin: a double-blind, vehicle-controlled study. JAMA. 1988;259:527-532.
12. Olsen E, Katz K, Levine N, et al. Tretinoin emollient cream: A new therapy for photodamaged skin. J Am Acad Dermatol. 1992;26:215-224.
13. Sachs DL, Voorhees JJ. 2014. Vitamin A: Retinoids and the treatment of aging skin. In PK Farris (Ed). Cosmeceutical and Cosmetic Practice. pp. 81-93. West Sussex, UK. Wiley and Sons.
14. Sorg O, Antille C, Kaya G, Hilaire-Saurat J. Retinoids in cosmeceuticals. Dermatol Ther. 2006;19:289-296.
15. Kurlansky SB, Xiao J, Duell EA, et al. Biological activity of all-trans retinol requires metabolic conversion to all-trans retinoic acid and is mediated through activation of nuclear retinoid receptors in human keratinocytes. J Biol Chem. 1994;269(52):32821-32827.K
16. Fluhr J. Vienne NP, Lauze C, et al. Tolerance profile of retinol, retinaldehyde and retinoic acid under maximized and long-term clinical conditions. Dermatology. 1999;199:57-60.
17. Duell EA, Kang S, Voorhees JJ. Unoccluded retinol penetrates human skin in vivo more effectively than unoccluded retinyl pamitate or retinoic acid. J Invest Dermatol. 1997;109:301-305.
18. Tucker-Samaras S, Zekayko T, Cole C et al. A stabilized 0.1% retinol facial moisturizer improves the appearance of photodamaged skin in an eight-week, double-blind, vehicle- controlled study. J Drug Dermatol. 20009;8(10):932-936.
2. Fisher GJ, Voorhees Molecular mechanisms of retinoids actions in the skin. FASEB J. 1996;10:1002-1013.
3. Semba RD. On the ‘discovery’ of vitamin A. Ann Nutr Metab. 2012;61:192-198.
4. Kligman LH, Gans EG. Re-emergence of topical retinol in dermatology. J Derm Treat. 2000;11:47-52.
5. Krutmann J, Boulac A, Sore G, et al. The skin aging exposome. J Dermatol Sci. 2017;85(3):152-161.
6. Rittie L and Fisher GJ. Natural and sun-induced aging of human skin. Cold Springs Harb Perspect Med. 2015:5:a015370.
7. Fisher GJ, Wang Z, Datta SC, et al. Pathophysiology of premature skin aging induced by ultraviolet light. N Engl J Med. 1997;13:337(20):1419-28.
8. Kligman LG, Duo CH, Kligman AM. Topical tretinoin enhances repair of ultraviolet damaged dermal connective tissue. Connect Tissue Res. 1984;12(2):139-150.
9. Cordero AJ. La vitamina a acida en la piel senile. Actualiz Terapeut Dermatologica. 1983;6:49-54.
10. Kligman LH and Kligman AM. The nature of photoaging; Its prevention and repair. Photodermatol. 1986;3:215-227.
11. Weiss JS, Ellis CN, Headington JT et al. Topical tretinoin improves photoaged skin: a double-blind, vehicle-controlled study. JAMA. 1988;259:527-532.
12. Olsen E, Katz K, Levine N, et al. Tretinoin emollient cream: A new therapy for photodamaged skin. J Am Acad Dermatol. 1992;26:215-224.
13. Sachs DL, Voorhees JJ. 2014. Vitamin A: Retinoids and the treatment of aging skin. In PK Farris (Ed). Cosmeceutical and Cosmetic Practice. pp. 81-93. West Sussex, UK. Wiley and Sons.
14. Sorg O, Antille C, Kaya G, Hilaire-Saurat J. Retinoids in cosmeceuticals. Dermatol Ther. 2006;19:289-296.
15. Kurlansky SB, Xiao J, Duell EA, et al. Biological activity of all-trans retinol requires metabolic conversion to all-trans retinoic acid and is mediated through activation of nuclear retinoid receptors in human keratinocytes. J Biol Chem. 1994;269(52):32821-32827.K
16. Fluhr J. Vienne NP, Lauze C, et al. Tolerance profile of retinol, retinaldehyde and retinoic acid under maximized and long-term clinical conditions. Dermatology. 1999;199:57-60.
17. Duell EA, Kang S, Voorhees JJ. Unoccluded retinol penetrates human skin in vivo more effectively than unoccluded retinyl pamitate or retinoic acid. J Invest Dermatol. 1997;109:301-305.
18. Tucker-Samaras S, Zekayko T, Cole C et al. A stabilized 0.1% retinol facial moisturizer improves the appearance of photodamaged skin in an eight-week, double-blind, vehicle- controlled study. J Drug Dermatol. 20009;8(10):932-936.
