Vitamin C Summary

Topical vitamin C must be in the form of L-ascorbic acid to be useful to the body and skin. L-ascobic acid is unstable and tends to break down rapidly, that's why it is so difficult to produce for cosmetic preparations. Once it is in the skin L-ascorbic acid stimulates collagen synthesis, provides photoprotection, stays in the skin or up to 72 hours, and prevents UV immunosuppression.

"Vitamin C is a water-soluble antioxidant and the most plentiful antioxidant in the skin." Farris PK. Topical vitamin C: A useful agent for treating photoaging and other dermatologic conditions. Dermatol Surg 2005;31:814-818 - Shindo Y, Witt E, Hans D, Epstein W, Packer L. Enzymic and nonenzymic antioxidants in epidermis and dermis of human skin. J Invest Dermatol 1994;102:122-124.

Vitamin C and Collagen

Vitamin C is the only antioxidant that has been proven to increase collagen synthesis. Collagen synthesis is essential to maintain healthy skin. Collagen decreases with aging and photoaging accelerates the decrease. L-ascorbic acid serves as a signal, relaying a critical message to collagen genes to synthesize collagen, as well as being a cofactor for two enzymes important in collagen synthesis.

"L-ascorbic acid, an alpha-hydroxy acid, is a cofactor for collagen synthesis and is naturally found in fruits, vegetables, and tea." Van Scott E, Ditre CM, Yu RJ. Alpha-hydroxyacids in the treatment of signs of photoaging. Clin Dermatol 1996;14:217-226. - Phillips CL, Combs SB, Pinnell SR. Effects of ascorbic acid on proliferation and collagen synthesis in relation to the donor age of human dermal fibroblasts. J Invest Dermatol 1994;103:228-232. -  Colven RM, Pinnell SR. Topical Vitamin C in aging. Clin Dermatol 1996;14:227-234.

"In 2002, Fitzpatrick and Rostan27 applied 10% vitamin C to the cheek of volunteers and compared it with the opposite untreated cheek. At 12 weeks, biopsy specimens revealed an increase in the Grenz zone collagen (the connective tissueimmediately beneath the epidermis) and increased gene expression of type I collagen in the skin. There have even been significant changes noted with lower concentrations of

vitamin C". Fitzpatrick RE, Rostan EF. Double-blind, half-face study comparingtopical Vitamin C and vehicle for rejuvenation of photodamage.Dermatol Surg 2002;28:231-236

"In another randomized double-blinded placebo-controlled study, 5% vitaminC applied to one forearm of volunteers and placebo to the other forearm for 6 months resulted in increased expression of collagen I, collagen III, and tissue inhibitor of matrix metalloproteinase on the treated side I." Nusgens BV, Humbert P, Rougier A, Colige AC, Haftek M, Lambert CA, et al. Topically applied vitamin C enhances the mRNA level of collagens I and III, their processing enzymes and tissue inhibitor of matrix metalloproteinase I in the human dermis. J Invest Dermatol 2001;116:853-859.

"Similar studies with 5% vitamin C also found an increase in elastic fibers and more uniform distribution of type I collagen bundles." Humbert PG, Haftek M, Creidi P, Lapiere C, Nusgens B, Richard A, et al. Topical ascorbic acid on photoaged skin. Clinical, topographical and ultrastructural evaluation: double-blind study vs placebo. Exp Dermatol 2003;12:237-244.

"In 2004, Sauermann et al investigated the epidermal-dermal junction and depth of dermal papilla in volunteers of all ages and found that as people age, the papillae and its nutritive capillary decrease in density. They then applied topical 3% vitamin C on the forearm of volunteers and saw that there was an increase in the dermal papillae with new vessel formation after 1 month of treatment, compared with the opposite forearm where placebo was applied. Sauermann K, Jaspers S, Koop U, Wenck H. Topically applied Vitamin C increases the density of dermal papillae in aged human skin. BMC Dermatology 2004;4:13.

Vitamin C (and E) and Sun Protection

Vitamin C is what is known as an antioxidant. Antioxidants protect skin by neutralizing free radicals, which would otherwise destroy skin and its components. These free radicals are stimulated by ultraviolet light and also occur naturally in the oxygen atmosphere.

"Ultraviolet (UV) radiation-induced oxidative stress may result in acute and chronic photodamage. Based on the endogenous antioxidant system, the administration of antioxidants for scavenging reactive oxygen species might be a promising strategy in the prevention of UV-induced skin reactions. The relevance of the most common antioxidants, vitamins E and C, is reviewed focusing on topical and systemic photoprotective effects in animals and humans.

Topically applied vitamin C induced significant photoprotective effects at concentrations of at least 10% in animals and humans, whereas a photoprotective effect has not been demonstrated by oral administration even at high doses in humans. Topical vitamin E reduced erythema, sunburn cells, chronic UV-B-induced skin damage, and photocarcinogenesis in the majority of the published studies, whereas only high doses of oral vitamin E may affect the response to UV-B in humans. Combination of vitamins C and E, partly with other photoprotective compounds, did increase the photoprotective effects dramatically compared to monotherapies.

This synergistic interplay of several antioxidants should be taken into consideration in future research on cutaneous photoprotection."B Eberlein-Konig1,2 & J Ring2. Relevance of vitamins C and E in cutaneous photoprotection . 1.Division of Environmental Dermatology and Allergology GSF/TUM, Neuherberg-Munich, Germany. 2.Department of Dermatology and Allergy Biederstein, Technical University Munich, Germany

"The combination of 15% L-ascorbic acid and 1% alpha-tocopherol provided significant protection against erythema and sunburn cell formation; either L-ascorbic acid or 1% alpha-tocopherol alone also was protective but the combination was superior. Application during 4 days provided progressive protection that yielded an antioxidant protection factor of 4-fold. In addition, the combination of vitamins C and E provided protection against thymine dimer formation." Lin JY, Selim MA, Shea CR, Grichnik JM, Omar MM, Monteiro-Riviere NA, Pinnell SR. UV photoprotection by combination topical antioxidants vitamin C and vitamin E.  Department of Medicine, Duke University Medical Center Read more

"Topical L-ascorbic acid (10% solution, twice daily for 3 days prior to UV exposure) induced a 40% reduction of sunburn cells and a 50% reduction in erythema in UVB irradiated porcine skin." Darr D, Combs S, Dunston S et al. Topical vitamin C protects porcine skin from ultraviolet radiation-induced damage. Br J Dermatol 1992; 127 : 247-53.

"Application of a 15% L -ascorbic acid solution to pig skin daily for 4 days protected twofold against solar-simulated UV erythema when compared with vehicle-treated skin." Lin J, Selim M, Shea C et al. UV photoprotection by combination topical antioxidants vitamin C and vitamin E. J Am Acad Dermatol 2003; 48 : 866-74.

"Topical L -ascorbic acid (10% solution, concentration of 0.5- 5 u mol/cm 2 , respectively) was able to reduce UV-B-induced immunosuppression and systemic tolerance to contact allergens in murine skin." Nakamura T, Pinnell SR, Darr D et al. Vitamin C abrogates the deleterious effects of UVB radiation on cutaneous immunity by a mechanism that does not depend on TNFalpha. J Invest Dermatol 1997; 109 : 20-4. - Steenvoorden DP, Beijersbergen van Henegouwen G. Protection against UV-induced systemic immunosuppression in mice by a single topical application of the antioxidant vitamins C and E. Int J Radiat Biol 1999; 75 : 747-55.

"Bissett and coworkers showed that topical ascorbic acid in mice effectively minimized chronic damage to low UVB doses, but not to UVA irradiation." Bissett DL, Chatterjee R, Hannon DP. Photoprotective effect of superoxide-scavenging antioxidants against ultraviolet radiation-induced chronic skin damage in the hairless mouse. Photodermatol Photoimmunol Photomed 1990; 7: 56-62.

"In a human study, volunteers were treated with 10% solution of L -ascorbic acid or vehicle controls (5 days prior to irradiation) before UV-B irradiation. Sites treated with topical vitamin C showed a significant reduction of the minimal erythema dose." Murray J, Darr D, Rich J, Pinnell S. Topical vitamin C treatment reduces ultraviolet B radiation-induced erythema in human skin [abstract]. J Invest Dermatol 1991; 96: 587.

"Application of a 5% solution of L-ascorbic acid 30 min before ultraviolet irradiation showed a modest, not significant effect." Dreher F, Gabard B, Schwindt DA, Maibach HI. Topical melatonin in combination with vitamins E and C protects skin from ultraviolet-induced erythema: a human study in vivo. Br J Dermatol 1998; 139: 332-9.

I"n contrast, one single application of a 10% solution immediately after UV-B irradiation significantly reduced the minimal erythema dose..." Eberlein-Konig B. Parameter der UVBStrahlungsempfindlichkeit des Menschen: in-vitro- und invivo- Modelle zur Prufung photosensibilisierender und photoprotektiver Substanzen. Shaker Verlag; Aachen; 2003.

"...whereas a 5% solution did not. " Dreher F, Denig N, Gabard B et al. Effect of topical antioxidants on UV-B-induced erythema formation when administered after exposure. Dermatology 1999; 198: 52-5." Journal of Cosmetic Dermatology Volume 4 Issue 1 Page 4 - January 2005

" Reports comparing the clinical appearance of mild to moderately photodamaged facialskin after a 3-month application of 10% topical vitamin C (Cellex-C; Cellex-C International, Toronto, Ontario, Canada) to the hemi-face found statistically significantimprovement compared with the untreated hemi-face with respect to surface texture, fine wrinkling, tactile roughness, coarse rhytids, skin laxity, and sallowness." Traikovich SS. Use of topical ascorbic acid and its effects on photodamaged skin topography. Arch Otolaryngol Head Neck Surg 1999;125:1091-1098.

"Many groups have used optical profilometry to demonstrate significant improvements in skin texture, wrinkling, and roughness with vitamin C treatment." Rubino C, Farace F, Dessy LA, Sanna MP, Mazzarello V. A prospective study of anti-aging topical therapies using a quantitative method of assessment. Plast Reconstr Surg 2005;115:1156-1162.

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