Abstract
The formation of dioxygenated metabolites of cholesterol, epicholesterol (5-cholesten-3α-ol) 4-cholesten-3β-ol, 4-cholesten-3α-ol, 4-cholesten-3-one and 4-stigmasten-3-one was studied after incubations with soybean lipoxygenase and linoleic acid. From cholesterol and epicholesterol were formed the 7α-hydroxy-, 7α-hydroperoxy-, 7β-hydroxy-, 7β-hydroperoxy-, 7-oxo and 5,6-epoxyderivatives as well as 6β-hydroxy-4-cholesten-3-one. All Δ4-steroids were hydroxylated in the 6α- and 6β-positions. The ratios between the yields of 6β- and 6α-hydroxylated metabolites varied between 3∶1 and 2∶1. Incubations with 4-cholesten-3α-ol and 4-cholesten-3β-ol also afforded the 4,5-epoxides of these steroids. The ratios between the yields of the 4β,5β- and 4α,5α-epoxides were ca. 4∶1 for 4-cholesten 3β-ol and ca. 3∶2 for 4-cholesten-3α-ol. With iron-supplemented microsomes from rat liver, the compounds formed were qualitatively and quantitatively the same as with soybean lipoxygenase, whereas with 18,000 × g rat liver supernatant fractions the yields of all products formed—except 7α-hydroxycholesterol and 6β-hydroxy-4-cholesten-3-one—were markedly decreased. The results indicate the presence of a rat liver microsomal 6β-hydroxylase which can use 4-cholesten-3-one as a substrate and extend previous findings of similarities between soybean lipoxygenase and a nonspecific lipoxygenase in rat liver microsomes.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Johansson, G., Eur. J. Biochem. 21:68 (1971).
Aringer, L and P. Eneroth, J. Lipid Res. 15:389 (1974).
Teng, J.I. and L.L. Smith, J. Am. Chem. Soc. 95:4060 (1973).
Teng, J.I. and L.L. Smith, Bioorganic Chem. 5:99 (1976).
Teng, J.I. and L.L. Smith, J. Steroid Biochem. 7:577 (1976).
Aringer, L., J. Lipid. Res. 19:933 (1978).
Aringer, L., Thesis, The Library of Karolinska Institutet, S-104 01 Stockholm, Sweden, 1975.
Henbest, H.B. and W.R. Jackson, J. Chem. Soc. 2459 (1967).
Makita, M. and W.W. Wells, An. Biochem. 5:523 (1963).
Aringer, L., P. Eneroth and J.-Å. Gustafsson, Steroids 17:377 (1971).
Collins, D.J., J. Chem. Soc. 3919 (1959).
Eneroth, P. and E. Nyström, Steroids 11:187 (1968).
Kulig, M.J. and L.L. Smith, J. Org. Chem. 38:3639 (1973).
Richmond, W., Clin. Chem. 19:1350 (1973).
Aringer, L. and P. Eneroth, J. Lipid Res. 14:563 (1973).
Ellingboe, J., E. Nyström and J. Sjövall, J. Lipid Res. 11:266 (1970).
Mitton, J.R., N.A. Scholan and G.S. Boyd, Eur. J. Biochem. 20:569 (1971).
Aringer, L., J. Lipid Res. 16:426 (1975).
Plattner, P.A., H. Heusser and A.B. Kulkarni, Helv. Chim. Acta 31:1885 (1948).
Aringer, L., P. Eneroth and L. Nordström, J. Lipid. Res. 17:263 (1976).
Smith, L.L., M.J. Kulig and J.I. Teng, Chem. Phys. Lipids 20:211 (1977).
Kulig, M.J. and L.L. Smith, J. Org. Chem. 39:3398 (1974).
Pistorius, J.C.E. and B. Axelrod, Biochim. Biophys. Acta 198:12 (1970).
Verhue, W.M. and A. Francke, Biochim. Biophys. Acta 284:43 (1972).
Hochstein, P. and L. Ernster, Biochem. Biophys. Res. Commun. 12:388 (1963).
Author information
Authors and Affiliations
About this article
Cite this article
Aringer, L. Oxidation of 3-oxygenated Δ4- and Δ5-C27 steroids by soybean lipoxygenase and rat liver microsomessteroids by soybean lipoxygenase and rat liver microsomes. Lipids 15, 563–571 (1980). https://doi.org/10.1007/BF02534180
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF02534180