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. 1997 Feb 15;322(Pt 1):175–184. doi: 10.1042/bj3220175

Metabolism of 27-, 25- and 24-hydroxycholesterol in rat glial cells and neurons.

J Zhang 1, Y Akwa 1, M el-Etr 1, E E Baulieu 1, J Sjövall 1
PMCID: PMC1218174  PMID: 9078259

Abstract

The metabolism of 27-, 25- and 24-hydroxycholesterol in cultures of rat astrocytes, Schwann cells and neurons was studied. 27- and 25-Hydroxycholesterol, but not 24-hydroxycholesterol, underwent 7 alpha-hydroxylation with subsequent oxidation to 7 alpha-hydroxy-3-oxo-delta 4 steroids in all three cell types. When cells were incubated for 24 h with 0.28 nmol of 27-hydroxycholesterol in 10 ml of medium, the rates of conversion into 7 alpha-hydroxylated metabolites were 0.21, 0.12 and 0.02 nmol/24 h per 10(6) cells in the media of astrocytes, Schwann cells and neurons respectively. The corresponding values for 25-hydroxycholesterol were 0.26, 0.16 and 0.04. A minor fraction of 27-hydroxycholesterol and its 7 alpha-hydroxylated metabolites was oxidized to 3 beta-hydroxy-5-cholestenoic acid. 3 beta, 7 alpha-dihydroxy-5-cholestenoic acid and 7 alpha-hydroxy-3-oxo-4-cholestenoic acid. In addition to the two hydroxycholesterols, other 3 beta-hydroxy-delta 4 steroids, dehydro-epiandrosterone, pregnenolone, 3 beta-hydroxy-5-cholestenoic acid and 3 beta-hydroxy-5-cholenoic acid underwent 7 alpha-hydroxylation. Competitive experiments did not distinguish between the presence of one or several 7 alpha-hydroxylases. In astrocyte incubations, 27-hydroxycholesterol also underwent 25-hydroxylation, and 12% of its metabolites carried a 25-hydroxy group. 25-Hydroxylation of added 24-hydroxycholesterol was also observed in the astrocyte incubations, as was the formation of 7 alpha, 25-dihydroxy-4-cholesten-3-one, 25-hydroxycholesterol and 7 alpha, 25-dihydroxycholesterol from endogenous precursor(s). Our study indicates that side-chain oxygenated cholesterol can undergo metabolic transformations that may be of importance for cholesterol homoeostasis in the brain.

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Selected References

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  1. Akwa Y., Morfin R. F., Robel P., Baulieu E. E. Neurosteroid metabolism. 7 alpha-Hydroxylation of dehydroepiandrosterone and pregnenolone by rat brain microsomes. Biochem J. 1992 Dec 15;288(Pt 3):959–964. doi: 10.1042/bj2880959. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Akwa Y., Sananès N., Gouézou M., Robel P., Baulieu E. E., Le Goascogne C. Astrocytes and neurosteroids: metabolism of pregnenolone and dehydroepiandrosterone. Regulation by cell density. J Cell Biol. 1993 Apr;121(1):135–143. doi: 10.1083/jcb.121.1.135. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Akwa Y., Schumacher M., Jung-Testas I., Baulieu E. E. Neurosteroids in rat sciatic nerves and Schwann cells. C R Acad Sci III. 1993;316(4):410–414. [PubMed] [Google Scholar]
  4. Andersson S., Davis D. L., Dahlbäck H., Jörnvall H., Russell D. W. Cloning, structure, and expression of the mitochondrial cytochrome P-450 sterol 26-hydroxylase, a bile acid biosynthetic enzyme. J Biol Chem. 1989 May 15;264(14):8222–8229. [PubMed] [Google Scholar]
  5. Axelson M., Larsson O., Zhang J., Shoda J., Sjövall J. Structural specificity in the suppression of HMG-CoA reductase in human fibroblasts by intermediates in bile acid biosynthesis. J Lipid Res. 1995 Feb;36(2):290–298. [PubMed] [Google Scholar]
  6. Axelson M., Mörk B., Sjövall J. Occurrence of 3 beta-hydroxy-5-cholestenoic acid, 3 beta,7 alpha-dihydroxy-5-cholestenoic acid, and 7 alpha-hydroxy-3-oxo-4-cholestenoic acid as normal constituents in human blood. J Lipid Res. 1988 May;29(5):629–641. [PubMed] [Google Scholar]
  7. Axelson M., Shoda J., Sjövall J., Toll A., Wikvall K. Cholesterol is converted to 7 alpha-hydroxy-3-oxo-4-cholestenoic acid in liver mitochondria. Evidence for a mitochondrial sterol 7 alpha-hydroxylase. J Biol Chem. 1992 Jan 25;267(3):1701–1704. [PubMed] [Google Scholar]
  8. Axelson M., Sjövall J. Potential bile acid precursors in plasma--possible indicators of biosynthetic pathways to cholic and chenodeoxycholic acids in man. J Steroid Biochem. 1990 Aug 28;36(6):631–640. doi: 10.1016/0022-4731(90)90182-r. [DOI] [PubMed] [Google Scholar]
  9. Björkhem I., Gustafsson J. Mitochondrial omega-hydroxylation of cholesterol side chain. J Biol Chem. 1974 Apr 25;249(8):2528–2535. [PubMed] [Google Scholar]
  10. Björkhem I., Holmberg I., Oftebro H., Pedersen J. I. Properties of a reconstituted vitamin D3 25-hydroxylase from rat liver mitochondria. J Biol Chem. 1980 Jun 10;255(11):5244–5249. [PubMed] [Google Scholar]
  11. Björkhem I., Nyberg B., Einarsson K. 7 alpha-hydroxylation of 27-hydroxycholesterol in human liver microsomes. Biochim Biophys Acta. 1992 Sep 22;1128(1):73–76. doi: 10.1016/0005-2760(92)90259-x. [DOI] [PubMed] [Google Scholar]
  12. Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1006/abio.1976.9999. [DOI] [PubMed] [Google Scholar]
  13. Cali J. J., Russell D. W. Characterization of human sterol 27-hydroxylase. A mitochondrial cytochrome P-450 that catalyzes multiple oxidation reaction in bile acid biosynthesis. J Biol Chem. 1991 Apr 25;266(12):7774–7778. [PubMed] [Google Scholar]
  14. Celotti F., Melcangi R. C., Negri-Cesi P., Ballabio M., Martini L. Differential distribution of the 5-alpha-reductase in the central nervous system of the rat and the mouse: are the white matter structures of the brain target tissue for testosterone action? J Steroid Biochem. 1987 Jan;26(1):125–129. doi: 10.1016/0022-4731(87)90040-9. [DOI] [PubMed] [Google Scholar]
  15. Dhar A. K., Teng J. I., Smith L. L. Biosynthesis of cholest-5-ene-3beta, 24-diol (cerebrosterol) by bovine cerebral cortical microsomes. J Neurochem. 1973 Jul;21(1):51–60. doi: 10.1111/j.1471-4159.1973.tb04224.x. [DOI] [PubMed] [Google Scholar]
  16. Dueland S., Trawick J. D., Nenseter M. S., MacPhee A. A., Davis R. A. Expression of 7 alpha-hydroxylase in non-hepatic cells results in liver phenotypic resistance of the low density lipoprotein receptor to cholesterol repression. J Biol Chem. 1992 Nov 15;267(32):22695–22698. [PubMed] [Google Scholar]
  17. Groyer A., Robel P. DNA measurement by mithramycin fluorescence in chromatin solubilized by heparin. Anal Biochem. 1980 Jul 15;106(1):262–268. doi: 10.1016/0003-2697(80)90146-3. [DOI] [PubMed] [Google Scholar]
  18. Ichimiya H., Egestad B., Nazer H., Baginski E. S., Clayton P. T., Sjövall J. Bile acids and bile alcohols in a child with hepatic 3 beta-hydroxy-delta 5-C27-steroid dehydrogenase deficiency: effects of chenodeoxycholic acid treatment. J Lipid Res. 1991 May;32(5):829–841. [PubMed] [Google Scholar]
  19. Johansson G. Oxidation of cholesterol, 3 -hydroxy-5-pregnen-20-one and 3 -hydroxy-5-androsten-17-one by rat liver microsomes. Eur J Biochem. 1971 Jul 15;21(1):68–79. doi: 10.1111/j.1432-1033.1971.tb01441.x. [DOI] [PubMed] [Google Scholar]
  20. Kandutsch A. A., Chen H. W., Heiniger H. J. Biological activity of some oxygenated sterols. Science. 1978 Aug 11;201(4355):498–501. doi: 10.1126/science.663671. [DOI] [PubMed] [Google Scholar]
  21. Khalil M. W., Strutt B., Vachon D., Killinger D. W. Effect of dexamethasone and cytochrome P450 inhibitors on the formation of 7 alpha-hydroxydehydroepiandrosterone by human adipose stromal cells. J Steroid Biochem Mol Biol. 1994 Apr;48(5-6):545–552. doi: 10.1016/0960-0760(94)90206-2. [DOI] [PubMed] [Google Scholar]
  22. Leighton J. K., Dueland S., Straka M. S., Trawick J., Davis R. A. Activation of the silent endogenous cholesterol-7-alpha-hydroxylase gene in rat hepatoma cells: a new complementation group having resistance to 25-hydroxycholesterol. Mol Cell Biol. 1991 Apr;11(4):2049–2056. doi: 10.1128/mcb.11.4.2049. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Lin Y. Y., Smith L. L. Sterol metabolism. 28. Biosynthesis and accumulation of cholest-5-ene-3beta, 24-diol (cerebrosterol) in developing rat brain. Biochim Biophys Acta. 1974 May 29;348(2):189–196. doi: 10.1016/0005-2760(74)90230-6. [DOI] [PubMed] [Google Scholar]
  24. Lund E., Andersson O., Zhang J., Babiker A., Ahlborg G., Diczfalusy U., Einarsson K., Sjövall J., Björkhem I. Importance of a novel oxidative mechanism for elimination of intracellular cholesterol in humans. Arterioscler Thromb Vasc Biol. 1996 Feb;16(2):208–212. doi: 10.1161/01.atv.16.2.208. [DOI] [PubMed] [Google Scholar]
  25. Lund E., Björkhem I., Furster C., Wikvall K. 24-, 25- and 27-hydroxylation of cholesterol by a purified preparation of 27-hydroxylase from pig liver. Biochim Biophys Acta. 1993 Feb 24;1166(2-3):177–182. doi: 10.1016/0005-2760(93)90094-p. [DOI] [PubMed] [Google Scholar]
  26. Lund E., Breuer O., Björkhem I. Evidence that 24- and 27-hydroxylation are not involved in the cholesterol-induced down-regulation of hydroxymethylglutaryl-CoA reductase in mouse liver. J Biol Chem. 1992 Dec 15;267(35):25092–25097. [PubMed] [Google Scholar]
  27. Martin K. O., Budai K., Javitt N. B. Cholesterol and 27-hydroxycholesterol 7 alpha-hydroxylation: evidence for two different enzymes. J Lipid Res. 1993 Apr;34(4):581–588. [PubMed] [Google Scholar]
  28. Nagata K., Takakura K., Asano T., Seyama Y., Hirota H., Shigematsu N., Shima I., Kasama T., Shimizu T. Identification of 7 alpha-hydroxy-3-oxo-4-cholestenoic acid in chronic subdural hematoma. Biochim Biophys Acta. 1992 Jun 22;1126(2):229–236. doi: 10.1016/0005-2760(92)90295-7. [DOI] [PubMed] [Google Scholar]
  29. Okuda K., Usui E., Ohyama Y. Recent progress in enzymology and molecular biology of enzymes involved in vitamin D metabolism. J Lipid Res. 1995 Aug;36(8):1641–1652. [PubMed] [Google Scholar]
  30. Payne D. W., Shackleton C., Toms H., Ben-Shlomo I., Kol S., deMoura M., Strauss J. F., Adashi E. Y. A novel nonhepatic hydroxycholesterol 7 alpha-hydroxylase that is markedly stimulated by interleukin-1 beta. Characterization in the immature rat ovary. J Biol Chem. 1995 Aug 11;270(32):18888–18896. doi: 10.1074/jbc.270.32.18888. [DOI] [PubMed] [Google Scholar]
  31. Pedersen J. I., Oftebro H., Björkhem I. Reconstitution of C27-steroid 26-hydroxylase activity from bovine brain mitochondria. Biochem Int. 1989 Mar;18(3):615–622. [PubMed] [Google Scholar]
  32. Princen H. M., Meijer P., Wolthers B. G., Vonk R. J., Kuipers F. Cyclosporin A blocks bile acid synthesis in cultured hepatocytes by specific inhibition of chenodeoxycholic acid synthesis. Biochem J. 1991 Apr 15;275(Pt 2):501–505. doi: 10.1042/bj2750501. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Saucier S. E., Kandutsch A. A., Clark D. S., Spencer T. A. Hepatic uptake and metabolism of ingested 24-hydroxycholesterol and 24(S),25-epoxycholesterol. Biochim Biophys Acta. 1993 Feb 10;1166(1):115–123. doi: 10.1016/0005-2760(93)90291-g. [DOI] [PubMed] [Google Scholar]
  34. Schumacher M., Jung-Testas I., Robel P., Baulieu E. E. Insulin-like growth factor I: a mitogen for rat Schwann cells in the presence of elevated levels of cyclic AMP. Glia. 1993 Aug;8(4):232–240. doi: 10.1002/glia.440080403. [DOI] [PubMed] [Google Scholar]
  35. Shoda J., Axelson M., Sjövall J. Synthesis of potential C27-intermediates in bile acid biosynthesis and their deuterium-labeled analogs. Steroids. 1993 Mar;58(3):119–125. doi: 10.1016/0039-128x(93)90048-r. [DOI] [PubMed] [Google Scholar]
  36. Shoda J., Toll A., Axelson M., Pieper F., Wikvall K., Sjövall J. Formation of 7 alpha- and 7 beta-hydroxylated bile acid precursors from 27-hydroxycholesterol in human liver microsomes and mitochondria. Hepatology. 1993 Mar;17(3):395–403. [PubMed] [Google Scholar]
  37. Skrede S., Björkhem I., Kvittingen E. A., Buchmann M. S., Lie S. O., East C., Grundy S. Demonstration of 26-hydroxylation of C27-steroids in human skin fibroblasts, and a deficiency of this activity in cerebrotendinous xanthomatosis. J Clin Invest. 1986 Sep;78(3):729–735. doi: 10.1172/JCI112633. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Smith A. G., Gilbert J. D., Harland W. A., Brooks C. J. The isolation of cholest-5-ene-3beta,26-diol from human brain. Biochem J. 1974 Jun;139(3):793–795. doi: 10.1042/bj1390793. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. Smith L. L. Cholesterol autoxidation 1981-1986. Chem Phys Lipids. 1987 Jul-Sep;44(2-4):87–125. doi: 10.1016/0009-3084(87)90046-6. [DOI] [PubMed] [Google Scholar]
  40. Smith L. L., Ray D. R., Moody J. A., Wells J. D., Van Lier J. E. 24-hydroxycholesterol levels in human brain. J Neurochem. 1972 Mar;19(3):899–904. doi: 10.1111/j.1471-4159.1972.tb01406.x. [DOI] [PubMed] [Google Scholar]
  41. Sulcová J., Stárka L. 7 -Hydroxylation of dehydroepiandrosterone in human testis and epididymis in vitro. Experientia. 1972 Nov 15;28(11):1361–1362. doi: 10.1007/BF01965346. [DOI] [PubMed] [Google Scholar]
  42. Tint G. S., Dayal B., Batta A. K., Shefer S., Cheng F. W., Salen G., Mosbach E. H. Gas-liquid chromatography-mass spectrometry of trimethylsilyl ethers of bile alcohols. J Lipid Res. 1978 Nov;19(8):956–966. [PubMed] [Google Scholar]
  43. Toll A., Shoda J., Axelson M., Sjövall J., Wikvall K. 7 alpha-hydroxylation of 26-hydroxycholesterol, 3 beta-hydroxy-5-cholestenoic acid and 3 beta-hydroxy-5-cholenoic acid by cytochrome P-450 in pig liver microsomes. FEBS Lett. 1992 Jan 13;296(1):73–76. doi: 10.1016/0014-5793(92)80406-7. [DOI] [PubMed] [Google Scholar]
  44. Toll A., Wikvall K., Sudjana-Sugiaman E., Kondo K. H., Björkhem I. 7 alpha hydroxylation of 25-hydroxycholesterol in liver microsomes. Evidence that the enzyme involved is different from cholesterol 7 alpha-hydroxylase. Eur J Biochem. 1994 Sep 1;224(2):309–316. doi: 10.1111/j.1432-1033.1994.00309.x. [DOI] [PubMed] [Google Scholar]
  45. Zhang J., Akwa Y., Baulieu E. E., Sjövall J. 7 Alpha-hydroxylation of 27-hydroxycholesterol in rat brain microsomes. C R Acad Sci III. 1995 Mar;318(3):345–349. [PubMed] [Google Scholar]
  46. Zhang J., Larsson O., Sjövall J. 7 alpha-Hydroxylation of 25-hydroxycholesterol and 27-hydroxycholesterol in human fibroblasts. Biochim Biophys Acta. 1995 Jun 6;1256(3):353–359. doi: 10.1016/0005-2760(95)00045-e. [DOI] [PubMed] [Google Scholar]
  47. el-Etr M., Cordier J., Glowinski J., Premont J. A neuroglial cooperativity is required for the potentiation by 2-chloroadenosine of the muscarinic-sensitive phospholipase C in the striatum. J Neurosci. 1989 May;9(5):1473–1480. doi: 10.1523/JNEUROSCI.09-05-01473.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]

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