Original Article

Journal of Investigative Dermatology (1979) 73, 141–143; doi:10.1111/1523-1747.ep12581580

Effects of Aging and Chronic Sun Exposure on Melanocytes in Human Skin

Barbara A Gilchrest1,2,3, Frederick B Blog1,2,3 and George Szabo1,2,3

  1. 1Department of Dermatology and Gerontology Unit, Beth Israel Hospital, Harvard Medical School, Boston, Massachusetts, U.S.A.
  2. 2Department of Dermatology, Erasmus University, Rotterdam, The Netherlands
  3. 3Laboratory of Electron Microscopy, Harvard School of Dental Medicine, Boston, Massachusetts, U.S.A.

Received 20 October 1978; Accepted 22 January 1979.

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Abstract

Both aging and sun exposure have well-documented effects on the human melanocyte system. Paired biopsies of habitually exposed and nonexposed skin from adjacnet anatomic sites were obtained from 8 donors aged 28 to 80 yr in order to study the combined effect of chronic actinic irradiation and chronologic aging. Density of dopa-positive melanocytes was roughly twofold higher in the exposed than in the nonexposed skin at all ages, suggesting an irreversible effect of sun exposure. Melanocyte density declined approximately 6 to 8% of the surviving population per decade in both sites. Dopapositivity of individual melanocytes was consistently greater in the chronically exposed skin than in the nonexposed skin of the same subject and did not vary with age. These data strengthen and expand earlier observations of age-related melanocyte changes, and explain the apparent paradox of a generalized increase in pigmentation and simultaneous decrease in melanocyte density which frequently accompany advancing age. In addition, the present study suggests that the principal effect of chronic sun exposure on the human pigmentary system is not premature "aging" as currently recognized histologically, but rather activation and/or proliferation of the exposed melanocytes.

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References

  1. Quevedo, WC Jr, Szabo, G, Virks, J: Influence of age and UV on the population of dopa-positive melanocytes in human skin. J Invest Dermatol 1969 52: 287–290,  | PubMed | ISI | ChemPort |
  2. Fitzpatrick, TB, Szabo, G, Mitchell, R: Age changes in the human melanocyte system, Advances in the Biology of Skin 1964 VI: Edited by W Montagna, Pergamon Press, Oxford, pp 35–50,
  3. Snell, RS, Bischitz, PG: The melanocytes and melanin in human abdominal wall skin: A survey made at different ages in both sexes and during pregnancy. J Anat Lond 1963 97: 361–376,
  4. Walsh, RG: Variation in the melanin content of the skin of New Guinea natives at different ages. J Invest Dermatol 1964 42: 261–265,  | PubMed |
  5. Papa, CM, Carter, DM, Kligman, AM: The effect of autotransplantation on the progression or reversibility of aging in human skin. J Invest Dermatol 1970 54: 200–212,  | PubMed | ChemPort |
  6. Pathak, MA, Sinesi, SJ, Szabo, G: The effect of a single dose of ultraviolet radiation on epidermal melanocytes. J Invest Dermatol 1965 45: 520–528,  | PubMed | ISI | ChemPort |
  7. Melski, JW, Tanenbaum, L, Parrish, JA: Oral methoxsalen photochemotherapy for the treatment of psoriasis: A cooperative clinical trial. J Invest Dermatol 1977 68: 328–335,  | Article | PubMed | ISI | ChemPort |
  8. Staricco, RJ, Pinkus, H: Quantitative and qualitative data on the pigment cells of adult human epidermis. J Invest Dermatol 1957 28: 33–45,  | PubMed | ISI | ChemPort |
  9. Billingham, RE, Medawar, PB: A study of the branched cells of the mammalian epidermis, with special reference to the fate of their division products. Phil Trans Roy Soc London 1953 237: 151–171,
  10. Szabo, G: The number of melanocytes in human epidermis. Br Med J 1954 1: 1016–1017,
  11. Rowe, JW: Clinical research on aging: Strategies and directions. N Engl J Med 1977 297: 1332–1336,  | PubMed |
  12. Szabo, G: Quantitative histological investigations on the melanocyte system of the human epidermis, Pigment Cell Biology 1959 Edited by M Gordon, Academic Press, New York, pp 99–125,
  13. Fitzpatrick, TB, Quevedo, WC Jr, Szabo, G, Seiji, M: Biology of the melanin pigmentary system, Dermatology in General Medicine 1971 Edited by TB Fitzpatrick et al. McGraw-Hill Book Co, New York, pp 128–130,
  14. Ebling, FJ, Rook, A: Disorders of skin colour, Textbook of Dermatology 1972 Edited by A Rook et al, Blackwell Scientific Publications, Oxford, pp 1242–1243,
  15. Ackerman, AB: Structure and function of the skin, Dermatology 1975 Edited by SL Moschella et al, W.B. Saunders Co, Philadelphia, p 30,

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