Steroid catabolism in marine and freshwater fish

Molecular Characterization of Zebrafish Oatp1d1 (Slco1d1), a Novel Organic Anion-transporting Polypeptide

“…Corticosteroid metabolism is also in part regulated by transporters. Oatp1d1, similarly to OATP1A2, transports cortisol, a crucial hormone in fish that acts as both glucocorticoid and mineralocorticoid, given that fish do not possess corticosterone and aldosterone (40,41). In summary, our data strongly suggest that the role of OATP/Oatp transporters in steroid catabolism is conserved from fish to mammals and that Oatp1d1 fulfills that role in zebrafish.…”

“…Inhibition of Oatp1d1 by nonconjugated steroids could reduce the uptake of conjugated steroid hormones in target tissues, depending on the fine hormonal balance in the plasma. In that sense, transporters, and more specifically Oatp1d1, would be involved in the negative feedback loop regulation of steroid hormone synthesis (40). Corticosteroid metabolism is also in part regulated by transporters.…”

Functional characterization of CYP1A9 and CYP1C1 from Anguillus japonica

“…Whereas the microsomal fraction from trout kidney was shown to hydroxylate progesterone at the 6β and 16α positions (Andersson and Rafter 1990;James 2011).…”

Steroidogenesis and phase II conjugation during the gametogenesis of thicklip grey mullet (Chelon labrosus) from a population showing intersex condition

“…Phase II metabolism enzymes such as glucuronosyltransferases (UGTs), sulfotransferases (SULTs) and glutathione-S-transferases (GST), are known to increase their activity toward endogenous substrates once reproductive maturation is completed, excreting the extra disposable hormones and endocrine sub-products (James, 2011). Sex steroid metabolism in liver and peripheral tissues often produces metabolites with reduced receptor affinity such as glucuronidated and sulfonated estrogens and androgens (Dawson, 2012;James, 2011).…”