4403 Galactitol Galactitol or dulcitol is a sugar alcohol that is a metabolic breakdown product of galactose. Galactose is derived from lactose in food (such as dairy products). When lactose is broken down by the enzyme lactase it produces glucose and galactose. Galactitol has a slightly sweet taste. It is produced from galactose in a reaction catalyzed by aldose reductase. When present in sufficiently high levels, galactitol can act as a metabotoxin, a neurotoxin, and a hepatotoxin. A neurotoxin is a compound that disrupts or attacks neural cells and neural tissue. A hepatotoxin as a compound that disrupts or attacks liver tissue or liver cells. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of galactitol are associated with at least two inborn errors of metabolism, including galactosemia and galactosemia type II. Galactosemia is a rare genetic metabolic disorder that affects an individual's ability to metabolize the sugar galactose properly. Excess lactose consumption in individuals with galactose intolerance or galactosemia activates aldose reductase to produce galactitol, thus depleting NADPH and leading to lowered glutathione reductase activity. As a result, hydrogen peroxide or other free radicals accumulate causing serious oxidative damage to various cells and tissues. In individuals with galactosemia, the enzymes needed for the further metabolism of galactose (galactose-1-phosphate uridyltransferase) are severely diminished or missing entirely, leading to toxic levels of galactose 1-phosphate, galactitol, and galactonate. High levels of galactitol in infants are specifically associated with hepatomegaly (an enlarged liver), cirrhosis, renal failure, cataracts, vomiting, seizure, hypoglycemia, lethargy, brain damage, and ovarian failure. 608-66-2 11850 C6H14O6 White powder. 189.5°C 31,0 mg/mL at 15°C Accumulation of galactitol in the body has been shown to be toxic. Accumulation of galactitol in the lens causes the osmotic phenomena and results in cataract formation. It may form in excess in the lens of the eye in galactosemias, a deficiency of galactokinase. No indication of carcinogenicity to humans (not listed by IARC). This is an endogenously produced metabolite found in the human body. It is used in metabolic reactions, catabolic reactions or waste generation. Chronically high levels of galactitol are associated with at least 2 inborn errors of metabolism including: Galactosemia and Galactosemia type II. 2014-08-29T06:31:18Z 2018-03-21T17:46:18Z Galactitol C01697 16813 15-DIDEOXY-15-IMINO-D-GALACTITOL true [H][C@](O)(CO)[C@@]([H])(O)[C@@]([H])(O)[C@]([H])(O)CO C6H14O6 InChI=1/C6H14O6/c7-1-3(9)5(11)6(12)4(10)2-8/h3-12H,1-2H2/t3-,4+,5+,6- InChIKey=FBPFZTCFMRRESA-GUCUJZIJNA-N 182.1718 182.07903818 Endogenous Solid -3.1 HMDB00107 CHEMBL1773904 11357 Muniruzzaman, Syed; Itoh, Hiromichi; Yoshino, Akira; Katayama, Takeshi; Izumori, Ken. Biotransformation of lactose to galactitol. Journal of Fermentation and Bioengineering (1994), 77(1), 32-5.