Genes that have been implicated in Larsen syndrome include filamin B , whichisinvolvedinthe cytoskeletal architecture, and carbohydrate sulphotransferase
3, which has also been implicated in other skeletal dysplasias .
Tibolone is also a sulphatase inhibitor, blocking conversion of oestrone sulphate to oestrone, as well as stimulating local sulphotransferase activity.
As stated previously, it inhibits oestradiol sulphatase but stimulates the sulphotransferase enzymes, which result in low levels of endogenous oestradiol in mammary tissue.
It was observed in vitro that Hg exposure significantly altered the androgen synthesis pathway by inhibiting hydroxysteroid sulphotransferase (HST) activity, thus reducing the conversion of dehydroepiandrosterone (DHEA) to dehydroepiandrosterone-sulphate (DHEAS) (21-24).
Studies on a 3beta-hydroxysteroid sulphotransferase from rat liver.
Macular corneal dystrophy type I and type II are caused by distinct mutations in a new sulphotransferase
In addition, in vitro studies showed that Hg exposure significantly inhibited hydroxysteroid sulphotransferase
(HST) activity, thus reducing the conversion of dehydroepiandrosterone (DHEA) to dehydroepiandrosterone-sulphate (DHEA-S) (130, 131).
DHEA is metabolized to form DHEAS, and both hormones are metabolically interconvertible by the action of the enzymes sulphotransferase
for conjugation and sulphatase for hydrolysis, present in many tissues (Baulieu, 1996).
Sulpho-conjugation of ethanol in humans in vivo and by individual sulphotransferase
forms in vitro.
The results confirmed that silymarin's phenolic compounds undergo extensive metabolism, as do almost all flavonoids, forming sulphate and glucuronide conjugates through the action of UDP-glucuronosyltransferases (UGTs) and sulphotransferases
(SULTs) in the small intestine and liver.
The metabolites derived by the action of human UDP-glucuronosyltransferases (UGTs) and sulphotransferases
(SULTs) were identified via the loss of the conjugating groups (i.
Most importantly one of the most potent effects of phytoestrogens is their ability to inhibit the sulphotransferases