Muzin

Term derived from the Greek (myxa = mucus). Mucins are glycoproteins consisting of a central protein chain and (long) side chains of sugar compounds (polysaccharides). They are functionally divided into two groups -:

• membrane-bound and
• secreted mucins.

Notwithstanding this, in humans they are numbered consecutively with the abbreviation "MUC" followed by a number (MUC1, MUC2, MUC3, etc.).

The mucins found in the skin consist of a mixture of glycosaminoglycans found in healthy skin, primarily hyaluronic acid and dermatan sulfate. Occur in bound (to proteins) form, as proteoglycans or in free form as hyaluronic acid and dermatan sulfate. Glycosaminoglycans are formed by fibroblasts and keratinocytes. They are the most important water-binding substances of the connective tissue and guarantee the consistency and turgor of the skin.

Mucins consist of a central protein with high glycosylation (bound polysaccharides). The polysaccharide chains give them a high water-binding capacity and thus protect the central protein from enzymatic degradation or the effects of acids.

Most cutaneous mucinoses result in an excessive production of mucins. Disturbances of degradation are also discussed.

1. Lobster LK (2014) Scleromyxedema. Curr Opin Rheumatol 26:658-662.
2. Ferretti VA et al (2016) Temporal and spatial expression of Muc2 and Muc5ac mucins during rat respiratory and digestive tracts development. Res Vet Sci 104:136-q45.
3. Krishn SR ET AL. (2016) Mucins and associated glycan signatures in colon adenoma-carcinoma sequence: Prospective pathological implication(s) for early diagnosis of colon cancer. Cancer Lett 374: 304-314.