Galactosamine

Galactosamine

File:Galactosamine.png
File:D-(+)-Galactosamine Structural Formulae V.1.svg
Names
IUPAC name 2-Amino-2-deoxy-D-galactose
Other names α-D-galactosamine
Identifiers
CAS Number	7535-00-4 checkY
3D model (JSmol)	Interactive image
ChEBI	CHEBI:60312 checkY
ChEMBL	ChEMBL207280 ☒N
ChemSpider	22576 checkY
ECHA InfoCard
E number
PubChem CID	24154
UNII	4Y6R29688W checkY
CompTox Dashboard (EPA)	{{#property:P3117}}
InChI InChI=1S/C6H13NO5/c7-3-5(10)4(9)2(1-8)12-6(3)11/h2-6,8-11H,1,7H2/t2-,3-,4+,5-,6?/m1/s1 checkY Key: MSWZFWKMSRAUBD-GASJEMHNSA-N checkY InChI=1/C6H13NO5/c7-3-5(10)4(9)2(1-8)12-6(3)11/h2-6,8-11H,1,7H2/t2-,3-,4+,5-,6?/m1/s1 Key: MSWZFWKMSRAUBD-GASJEMHNBA
SMILES O[C@H]1[C@@H](O)[C@H](OC(O)[C@@H]1N)CO
Properties
Chemical formula	C6H13NO5
Molar mass	179.172 g·mol−1
Melting point	180 °C (356 °F; 453 K) (HCl salt)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). ☒N verify (what is checkY☒N ?) Infobox references

Galactosamine is a hexosamine derived from galactose with the molecular formula C₆H₁₃NO₅. This amino sugar is a constituent of some glycoprotein hormones such as follicle-stimulating hormone (FSH) and luteinizing hormone (LH).

Precursors such as uridine diphosphate (UDP), UDP-N-acetyl-D-glucosamine, or glucosamine are used to synthesize galactosamine in the human body. A derivative of this compound is N-acetyl-D-galactosamine.

Galactosamine is a hepatotoxic, or liver-damaging, agent that is sometimes used in animal models of liver failure.

Hepatotoxicity

Galactosamine is used to induce hepatitis in rodent liver for research purposes. The result of using galactosamine to induce hepatitis is a disease model in which there is necrosis and inflammation of the liver. This type of tissue damage triggered by galactosamine resembles drug-induced liver disease in humans.

Mechanism of hepatotoxicity

The proposed mechanism behind galactosamine-induced hepatitis is depletion of the energy source of hepatocytes. In the Leloir pathway galactosamine is metabolized into galactosamine-1-phosphate (by galactokinase) and UDP-galactosamine (by UDP-galactose uridyltransferase). It is hypothesized that this leads to UDP-galactosamine accumulation within cells, and uridine triphosphate (UTP), UDP, and uridine monophosphate (UMP) decrease. The depletion of high-energy molecules such as UTP leads to a disruption in hepatocyte metabolism. Additionally, other derivatives of uridine such as UDP-glucose are depleted and this interferes with glycogen synthesis in the cell.

Another recent hypothesis states that overexpression of pro-inflammatory cytokines (such as tumor necrosis factor (TNFα) and NFκB-dependent inducible nitric oxide synthase (iNOS) over expression play a role in galactosamine-induced damage to liver cells.

See also

• N-Acetylgalactosamine
• Uridine

External links

• Galactosamine at the U.S. National Library of Medicine Medical Subject Headings (MeSH)