Steroid hormone hydroxylase specificities of eleven cDNA-expressed human cytochrome P450s.

@article{Waxman1991SteroidHH,
  title={Steroid hormone hydroxylase specificities of eleven cDNA-expressed human cytochrome P450s.},
  author={David J. Waxman and D P Lapenson and Toshifumi Aoyama and H. V. Gelboin and Frank J. Gonzalez and Kenneth Ray Korzekwa},
  journal={Archives of biochemistry and biophysics},
  year={1991},
  volume={290 1},
  pages={
          160-6
        }
}

Allelic variants of human cytochrome P450 1A1 (CYP1A1): effect of T461N and I462V substitutions on steroid hydroxylase specificity.

TLDR
Results indicate that all three naturally occurring allelic variants of human CYP1A1 hydroxylate steroid hormones with varying efficiencies in a stereo- and regioselective manner, whereby the CYP 1A1 T461N variant exhibited the lowest catalytic efficiency.

Cytochrome P450 3A9 catalyzes the metabolism of progesterone and other steroid hormones

TLDR
As a major isoform of CYP3A expressed in rat brain, the activities of P450 3A9 toward two major neurosteroids, progesterone and DHEA suggested a possible role for P4503A9 in the metabolism of neurosteroid metabolism.

16 α-Hydroxylation of estrone by human cytochrome P 4503 A 4 / 5

The cytochrome P450 (P450) enzymes that catalyse metabolism of the estrogen, estrone (E1), to the putative carcinogen 16α-hydroxy E1 (16α-OHE1) in humans were determined. The potential of the most

16Alpha-hydroxylation of estrone by human cytochrome P4503A4/5.

The cytochrome P450 (P450) enzymes that catalyse metabolism of the estrogen, estrone (E1), to the putative carcinogen 16alpha-hydroxy E1 (16alpha-OHE1) in humans were determined. The potential of the

Progesterone and testosterone hydroxylation by cytochromes P450 2C19, 2C9, and 3A4 in human liver microsomes.

TLDR
The results suggest that CYP2C19 plays important roles in the oxidation of progesterone and testosterone in human liver microsomes, although the physiological significance of these metabolic pathways remains unclear.

Differential activation of cyclophosphamide and ifosphamide by cytochromes P-450 2B and 3A in human liver microsomes.

TLDR
It is established that liver microsomal CYP2B and CYP3A preferentially catalyze cyclophosphamide and ifosphamide 4-hydroxylation, respectively, suggesting that liver P-450-inducing agents targeted at these enzymes might be used in cancer patients to enhance drug activation and therapeutic efficacy.

Separate and interactive regulation of cytochrome P450 3A4 by triiodothyronine, dexamethasone, and growth hormone in cultured hepatocytes.

TLDR
It is concluded that iodothyronines, glucocorticoids, and GH act directly on human hepatocytes to regulate the expression of CYP3A4, and these effects appear to be exerted at a pretranslational level.

Inhibition and activation of the human liver microsomal and human cytochrome P450 3A4 metabolism of testosterone by deployment-related chemicals.

TLDR
Kinetic analysis indicated that chlorpyrifos was one of the most potent inhibitors of major TST metabolites followed by fonofos and phorate, and inhibited major T ST metabolites noncompetitively and irreversibly.
...

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Results suggest that 2-Hydroxy- and/or 4-hydroxycatechol estrogens are further metabolized to other yet uncharacterized metabolites by P450s IIIA3 and IIIA4, and that these enzymes constitute the major forms catalyzing estradiol oxidation in human liver.

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Quantitative high-pressure liquid chromatographic assays were developed that separate progesterone and 17 authentic monohydroxylated derivatives and indicated that P-450k or an immunochemically related isozyme contributed greater than 80% of the 21-hydroxylase activity observed in microsomes from phenobarbital-induced rats.

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TLDR
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