Pigmentation disorders: causes and types

Violation of skin pigmentation is a cosmetic and often psychological problem. They can be small or occupy large areas of the skin. First of all, such changes have an unattractive appearance, but they can also be a symptom of dangerous diseases.

UV protection

As you know, the color of the skin depends on the presence of a special pigment in it - melanin, which is scattered in growth cells - melanocytes. It is synthesized from tyrosine as a result of complex chemical reactions. The enzyme that is responsible for the transformations that lead to the synthesis of melanin is tyrosinase.

Skin color depends mainly on the activity of melanocytes, that is, on the number of melanin granules produced. The number of melanocytes in individual parts of the body is different. Without pigments, our skin would be pale, and where blood vessels are close to the surface of the skin, there would be areas of pink skin.

Melanin contains two pigments - eumelanin (black-brown pigment) and pheomelanin (red-yellow pigment). They act in different ways: eumelanin reduces the penetration of solar radiation through the epidermis, and also has the ability to neutralize free radicals and has a sun protective effect. At the same time, pheomelanin is unstable to solar radiation, is potentially phototoxic and can damage deoxyribonucleic acid (DNA).

Violations of pigment formation occur both as a result of an increase in the production of pigments, and as a result of a decrease or complete absence of their production.

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This article is part of the special project Skin pigmentation and its correction

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