A broad field of action
for lightening agents
Cutaneous pigmentation is the outcome of two important events: the synthesis of pigment melanin by melanocytes and their transfer to surrounding keratinocytes. The process of protein synthesis is subjected to change on gene expression and post-translational level and is regulated through intracellular signalization incoming from external stimuli and receptors on cell surface. The final enzyme activity of proteins contributes to melanin synthesis in melanosome which is translocated towards the melanocyte dendrite tips into the recipient keratinocytes. Protein degradation, modulation of epidermal turnover and desquamation are another approach how to regulate skin pigmentation. There is no doubt that the skin pigmentation is a complex multistep process open to numerous influences. The focus of this review is to provide an overview of the melanin production mechanism and show ways in which new inhibitors of pigmentation could be targeted.
Humans have different colour skin depending on the distribution of pigment therein. Pigmentation is controlled genetically, environmentally and by endocrine factors modulating the amount, type and distribution of the pigment melanin in the skin. The main role of the pigment melanin is to protect the skin from ultraviolet radiation. Changes in skin colour have an impact not only on skin physiology, but also on social life, from the perspective of how we perceive beauty. On the one hand, tanning beds and bronzing lotions are used to give a tanned look, while on the other hand lightening agents are used to fight hyperpigmentation and adjust an even skin tone. New substances that inhibit melanogenesis are of great interest in the therapy of pigmentary diseases and reduced signs of ageing.
MELANOGENESIS IN THE SKIN
Although the surface of the human skin is suggestive of simplicity, it is actually one of the most complex and metabolically active organs, which, as the external shield of the body, is designed to interact and cope with the surrounding world. As a physical barrier, it prevents water loss and resists me ...