N-AcetylneuraminiC ACID(Sialic acids) are a family of nine-carbon acidic monosaccharides that occur naturally at the end of sugar chains attached to the surfaces of cells and soluble proteins. In the human body, the highest concentration of sialic acid (as N-acetylneuraminic acid) occurs in the brain where it participates as an integral part of ganglioside structure in synaptogenesis and neural transmission.
|Name||N-AcetylneuraminiC ACID (SIALIC ACID)|
|Chemical name||N-AcetylneuraminiC ACID|
|Molecular Weight||309.27 g/mol|
|Appearance||White crystal powder|
|Storage Condition||Store at room temperature, in a sealed airtight container, keep the air out, protected from heat, light and humidity.|
Sialic acid is a generic term for a family of derivatives of neuraminic acid, an acidic sugar with a nine-carbon backbone.It is also the name for the most common member of this group, N-acetylneuraminic acid (Neu5Ac or NANA).
N-AcetylneuraminiC ACID Sialic acids are found widely distributed in animal tissues and to a lesser extent in other organisms, ranging from fungi to yeasts and bacteria, mostly in glycoproteins and gangliosides (they occur at the end of sugar chains connected to the surfaces of cells and soluble proteins). That is because it seems to have appeared late in evolution. However, it has been observed in Drosophila embryos and other insects and in the capsular polysaccharides of certain strains of bacteria. Generally, plants do not contain or display sialic acids.
In humans the brain has the highest sialic acid concentration, where these acids play an important role in neural transmission and ganglioside structure in synaptogenesis. More than 50 kinds of sialic acid are known, all of which can be obtained from a molecule of neuraminic acid by substituting its amino group of one of its hydroxil groups. In general, the amino group bears either an acetyl or a glycolyl group, but other modifications have been described. These modifications along with linkages have shown to be tissue specific and developmentally regulated expressions, so some of them are only found on certain types of glycoconjugates in specific cells. The hydroxyl substituents may vary considerably; acetyl, lactyl, methyl, sulfate, and phosphate groups have been found.
In mammals, N-AcetylneuraminiC ACID(SIALIC ACID) is synthesized by the liver. It is an important nutrient in breast milk, which can promote the development of brain and nerve tissue in infants and young children, improve memory and intelligence, improve the immunity of infants and mothers;
N-AcetylneuraminiC ACID(SIALIC ACID) is not degraded by enzymes in the digestive tract, it forms glycoproteins that block the attachment of pathogens (viruses, bacteria and bacterial toxins) to the endocrine cells, and can improve cell identification, detoxify cholera toxins, prevent infection of pathological E. coli, regulate the half-life of blood proteins, and thus effectively improve human immune function. At the same time, N-AcetylneuraminiC ACID(SIALIC ACID) can improve the intestinal absorption of vitamins and minerals. Improve the immunity of the baby and the mother; N-AcetylneuraminiC ACID(SIALIC ACID) itself also contributes to the effect of stable birth, assists pregnant women to give birth smoothly, and accelerates postparto recovery.
The surface of human cells has a thick layer of N-AcetylneuraminiC ACID(SIALIC ACID), regulating cell life and cell information communication, N-AcetylneuraminiC ACID(SIALIC ACID) deficiency can lead to metabolic blood cell life and enzyme protein less. And oral N-AcetylneuraminiC ACID(SIALIC ACID) can improve the concentration of N-AcetylneuraminiC ACID(SIALIC ACID) in the body, prevent the cell surface N-AcetylneuraminiC ACID(SIALIC ACID) shedding, delay cell aging, has the role of longevity.
Sialic acid-rich glycoproteins (sialoglycoproteins) bind selectin in humans and other organisms. Metastatic cancer cells often express a high density of sialic acid-rich glycoproteins. This overexpression of sialic acid on surfaces creates a negative charge on cell membranes. This creates repulsion between cells (cell opposition) and helps these late-stage cancer cells enter the blood stream. Recent experiments have demonstrated the presence of sialic acid in the cancer-secreted extracellular matrix.
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