UV radiation is widely considered as a major cause of skin pigmentation. Upon exposure to UV radiation, the melanocytes
increase the production of intracellular nitric oxide, which triggers signal transduction cascades to initiate melanogenesis by tyrosinase.
UV radiation also influences melanogenesis through a paracrine regulation process involving the keratinocytes. Although
a number of hypopigmenting products have been developed, those from natural sources are preferred and will predominate in the
cosmetics market