Furthermore, these methodologies support the expression of scant, if any, CYP2B
Altered expression and glucocorticoid-inducibility of hepatic CYP3A and CYP2B
enzymes in male rats fed diets containing soy protein isolate.
Rodent cell lines have different CYP1A, CYP2B
and CYP3A expression levels and inducibilities compared to human cell lines (Westerink et al.
PCBs were grouped as follows: group 1, potentially estrogenic and weak phenobarbitol inducers (congeners 44, 49, 52, 101, 187, 174, 177, 157/201); group 2, potentially antiestrogenic and dioxin-like (congeners 95/66, 74, 77/110, 105/141, 118, 156, 167, 128, 138, 170); and group 3, phenobarbital, cytochrome P450 (CYP)1A, and CYP2B
inducers (congeners 99, 153, 180, 196/203, 183).
Phase I Phase II CYP1A2 Glutathione Stransferase * CYP2A6 CYP2B
N-acetyltransferase * CYP2C19 * UDP-glucuronosyltransferase * CYP2D6 * Sulfotransferases CYP2E1 * CYP3A NADPH-quinone Oxidoreductase * * Enzymes known to exhibit genetic polymorphism in humans.
Although PCB 153 and 180 are classified in group 3 and considered to be CYP1Al and CYP2B
inducers (Wolff et al.
Different regulation of the expression of mouse hepatic cytochrome P450 CYP2B
enzyme by glucocorticoid and phenobarbital.
(2005), liver expression of CYP1A1, CYP2B
, and CYP3A were analyzed after oral administration of DE-71 as well as individual congeners to adult rats on 3 consecutive days in doses ranging from 1.5 to 150 [micro]mol/kg BW/day.
Given that berberine metabolism involves CYP3A and CYP2B
in the rat (Liu et al.
1997) were as follows: Wolff group 1A, potentially estrogenic, weak phenobarbital inducers, not persistent congeners (PCB-52); Wolff group 2A, potentially antiestrogenic and immunotoxic, dioxin-like, non-ortho--and mono-ortho-substituted, moderately persistent congeners (PCB-74, PCB-105, PCB-118); Wolff group 2B, limited dioxin activity, di-ortho substituted, persistent congeners (PCB-138, PCB-170) and Wolff group 3, phenobarbital inducers, CYPlA and CYP2B
inducers, and persistent congeners (PCB-153, PCB-180, PCB-203).
The subtypes of CYP enzymes tested for were: ethoxyresorufin O-de-ethylase, CYPIA1; methoxyresorufin O-demethylase, CYPIA2; pentoxyresorufin O-dealkylase, CYP2B
; (S)-warfarin 7-hydroxyIase, CYP2C; p-nitrophenol hydroxylase, CYP2E1; and testosterone 6[beta]-hydroxylase, CYP3A.
In the current study, researchers grouped congeners on the basis of their reported abilities to induce the enzymes UDP-GT, CYP1A, and CYP2B
. UDP-GT has a role in [T.sub.4] elimination, and compounds that induce CYP1A and CYP2A are also likely to induce UDP-GT.