Ultraviolet (UV) irradiation is a major source of environmental damage to skin. Melanin
pigmentation protects against this damage by absorbing UV photons and UV-generated free …

Although the ability of UV irradiation to induce pigmentation in vivo and in vitro is well
documented, the intracellular signals that trigger this response are poorly understood. We …

Thymidine dinucleotide (pTpT) stimulates melanogenesis in mammalian pigment cells and
intact skin, mimicking the effects of UV irradiation and UV-mimetic DNA damage. Here it is …

We have determined that DNA damage is at least one of the signals generated by ultraviolet
radiation that stimulates pigmentation (tanning) in human skin. This photoprotective …

Tanning is a protective response of ultraviolet (UV)-irradiated skin that decreases damage
from subsequent sun exposures by increasing the epidermal content of melanin, a brown …

Highly pigmented, dark skin is more resistant to the harmful effects of solar ultraviolet
radiation than light-colored human skin. The extent to which tanning protects skin from …

Melanomas occur mainly in sunlight-exposed skin. Xeroderma pigmentosum (XP) patients
have 1,000-fold higher incidence of melanoma, suggesting that sunlight-induced “bulky” …

Although the induction of pigmentation following exposure of melanocytes to ultraviolet light
in vivo and in vitro is well documented, the intracellular mechanisms involved in this …

Epidermal melanin pigment is believed to prevent development of ultraviolet (UV)–induced
skin cancer by shielding cell nuclei and reducing DNA damage formation. It has not been …

Melanin protects the skin against DNA damage induced by direct absorption of sunlight's UV
radiation. Yet, irradiating melanin in vitro or in cultured cells also generates active oxygen …