Skin whitening
(From Wikipedia, the free encyclopedia)

Skin whitening is the practice of using substances, mixtures, or physical treatments to lighten skin color. Skin whitening treatments work by reducing the content of melanin of the skin. Many agents have been shown to be effective in skin whitening; some have beneficial side effects (e.g.: are antioxidantsnutrients, or decrease the risk of some types of cancer); some are a significant risk to health (for example, those containing mercury).




Specific zones of hyperpigmentation such as lentigo spots, moles and birthmarks may be depigmented to match to the surrounding skin. In cases of vitiligo, unaffected skin may be lightened to achieve a more uniform appearance.



Discovery and design[edit]
Melanogenesis inhibitors have been discovered and developed through several methods, including: screening of synthetic chemical libraries (high throughput screening is occasionally used), screening of plant extracts,computational (in silico) search,found as a side effect of previously known drugs and exploration of structural analogues of previously known tyrosinase inhibitors based on knowledge (in varying degrees) of their structure-activity relationship. Thus, the development and discovery of melanogenesis inhibitors illustrates many of the methods used in drug design. Some of the most potent competitive reversible tyrosinase inhibitors are synthetic compounds with a potency hundreds of times that of kojic acid.

合成のスクリーニング:メラニン形成阻害剤は、化学ライブラリー(ハイスループットスクリーニングを時折使用される)、植物抽出物のスクリーニング、計算(シリコで)検索などを含む、いくつかの方法によって発見され、開発されてきたが,以前から知られている薬物と、それらの構造活性相関(様々な程度での)知識に基づいた既知のチロシナーゼ阻害剤構造類似体探査 などの側効果が発見された。したがって、メラニン形成阻害剤の開発および発見は、薬物設計に使用される多くの方法を示している。最も強力な競合的可逆チロシナーゼインヒビターのいくつかは、コウジ酸の数百倍の効力を有する合成化合物である。


Mechanisms of action
See also: melanocyte, melanin, enzyme inhibitor, skin color, and hair color
For a review of mechanism of action of skin whitening agents, see Chang (2012)[12] or Ebanks, Wickett, Boissy (2009).[13]
Melanin is the main substance responsible for the color of the skin. Melanin is class of dark polymers generated by the body through the process of melanogenesis. Among the melanin pigmenting the skin and hair, 2 types can be distinguished based on its chemical composition and biological route of synthesis: the black/brown eumelanin and the red/yellow pheomelanin. The variation of skin color among individuals is mostly because of variation of the content of melanin in the skin. Skin with little or no melanin is almost white. Other factors influence skin color in a lesser degree, including the amount of blood in blood vessels (because of the color of blood), skin thickness and content of carotenoids in skin.[14][15]

メラニンは皮膚の色を担う主要な物質です。メラニンは、メラニン生成のプロセスを通じて体によって生成されるダークポリマーのクラスである。皮膚と髪を着色するメラニンのうち、その化学組成合成の生物学的経路:黒/茶色のユーメラニンと赤色/黄色のフェオメラニンに基づいて、2つのタイプを区別することができます。個体間での肌色の変化は、主に皮膚のメラニン含量の変動のためである。メラニンがほとんど、またはまったくない皮膚はほぼ白い。(血液の色のために)血管内の血液の量、皮膚の厚さおよび皮膚中のカロチノイドの含有量を含む他の要因は、皮膚の色にほとんど影響しない。[14] [15]