Metabolism of steroid hormones

R. Dorfman and F. Ungar, Metabolism of Steroid Hormones, Academic Press, New York, 1965. 

There are also numerous enzymes anchored in membranes of the microsomal cell fraction that participate in the metabolism of steroid hormones. Thus, those of the p450 family, which carry out molecular oxidation, or the sulfatases and sulfotransferases, more or less specific to several hormones (Pasqualini et al. 1995). The affinity of steroid hormones for proteins of the membrane (Kd between 10 and 100 nM) is frequently greater than that which some of these enzymes present for their substrates (Luzardo et al. 2000). Therefore, it is unlikely that a part of the proteins of the membrane that bind steroids is in reality enzymes metabolizing these hormones. 

A deficiency of liver function reduces metabolism of steroid hormones so that the blood concentration of oestrogens in men is increased. 

The inhibition by other organophosphate compounds of the carboxylesterase which hydrolyzes malathion is a further example of xenobiotic interaction resulting from irreversible inhibition because, in this case, the enzyme is phosphorylated by the inhibitor. A second type of inhibition involving organophosphorus insecticides involves those containing the P=S moiety. During CYP activation to the esterase-inhibiting oxon, reactive sulfur is released that inhibits CYP isoforms by an irreversible interaction with the heme iron. As a result, these chemicals are inhibitors of the metabolism of other xenobiotics, such as carbaryl and fipronil, and are potent inhibitors of the metabolism of steroid hormones such as testosterone and estradiol. 

Dorfman and Ungar have given an account of the metabolism of steroid hormones [10], therefore only a few comments v/ill be made here. The comparative relative activities of testosterone metabolities on the seminal vesicle and ventral prostate of immature male rats and capon s comb are summarized in the accompanying table. 

JR Gillette. Insights into deuterium isotope effects on the metabolism of steroid hormones and foreign compounds by cytochrome P-450 enzymes. Life Sci 49 1-14, 1991. 

Disease and Drug Protein Binding," and "Toxic Agents Resulting from the Oxidative Metabolism of Steroid Hormones and Drugs." ... 

A bibliography of steroid conjugates as well as a treatise on the metabolism of steroid hormones have been published. The abstracts of papers presented at the Second International Congress of Hormonal Steroids are available. ... 

For many years the metabolism of steroid hormones has been regarded largely as an irreversible detoxicating activity carried out mainly by the... 

D13. Dobriner, K., and Lieberman, S., The metabolism of steroid hormones in humans. Ciba Found. Colloq. Endocrinol. 2, 381—417 (1962). 

Dorfman Rl, Ungar F. Metabolism of Steroid Hormones. 2nd Ed. New York New York,... 

The work by Jones and Dobriner (1949) contains applications of infrared spectrometry to metabolism. A recent textbook on the metabolism of steroid hormones (Dorfman and Ungar, 1965) should be consulted for structures, nomenclature, and for the multifarious pathways in steroid metabolism, and for a discussion of conformational analysis of steroids. A chapter applying conformational analysis to steroids has been published by Eliel et al. (1965). A recently published handbook (Sober, 1968) shows the structures of 108 steroids and gives references to infrared data for many of them. The atlases by Neudert and Ropke (1965), Dobriner et al. (1953), and Roberts et al. (1958), are also very useful. Caspi and Scrimshaw (1967) have given some of the elementary aspects of the infrared spectroscopy of steroids. 

Dorfman, R. I., and Ungar, F. 1953. Metabolism of Steroid Hormones. Burgess Publ., Minneapolis, Minnesota. 

Chapter 12. METABOLISM OF STEROID HORMONES Leo T. Samuels and Kristen B. Eik-Nes... 

The effect of thyroid hormones on steroid metabolism is not restricted to cholesterol the metabolism of steroid hormones is also affected. An adequate understanding of the effects of thyroid hormones on steroid hormones requires a thorough knowledge of the intermediary metabolism of these hormones (see chapter on steroid hormones). 

Dorfman, R.L, Ungar, F. Metabolism of steroid hormones. New York Academic Press 1965... 

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