TY - JOUR
T1 - Metabolism of oral turinabol by the human brain cholesterol 24-hydroxylase CYP46A1
AU - Putkaradze, Natalia
AU - Hartz, Philip
AU - Hutter, Michael C
AU - Zapp, Josef
AU - Thevis, Mario
AU - Bernhardt, Rita
N1 - Copyright © 2021. Published by Elsevier Ltd.
Copyright © 2021 Elsevier Ltd. All rights reserved.
PY - 2021/9
Y1 - 2021/9
N2 - The human microsomal cytochrome P450 enzyme CYP46A1 plays a crucial role in cholesterol elimination from the brain. It performs a 24-hydroxylation of cholesterol and is of outstanding significance for memory and cognition. This study demonstrates the catalytic activity of human CYP46A1 towards an anabolic androgenic steroid, oral turinabol (dehydrochloromethyltestosterone, 4-chloro-17β-dihydroxy,17α-methylandrosta-1,4-dien-3-one), which is a doping substance. CYP46A1 is the first human microsomal steroid-converting P450 showing activity towards this xenobiotic compound. Furthermore, the inhibitory effect of oral turinabol on the cholesterol conversion has been investigated in vitro demonstrating competition of the two substrates on the active site of CYP46A1 which might be of importance for potential pathogenic effects of oral turinabol. The conversion of oral turinabol was found to be selective resulting in the formation of only one product, as shown by HPLC analysis. To produce sufficient amounts of this product for NMR analysis, a system expressing human full-length CYP46A1 and CPR on a bicistronic vector was successfully developed realizing the selective cholesterol 24-hydroxylation in E. coli in mg amounts. Using this novel whole-cell system, the conversion of oral turinabol was performed and the product of this conversion by CYP46A1 was isolated and identified as 16β-hydroxy oral turinabol by NMR.
AB - The human microsomal cytochrome P450 enzyme CYP46A1 plays a crucial role in cholesterol elimination from the brain. It performs a 24-hydroxylation of cholesterol and is of outstanding significance for memory and cognition. This study demonstrates the catalytic activity of human CYP46A1 towards an anabolic androgenic steroid, oral turinabol (dehydrochloromethyltestosterone, 4-chloro-17β-dihydroxy,17α-methylandrosta-1,4-dien-3-one), which is a doping substance. CYP46A1 is the first human microsomal steroid-converting P450 showing activity towards this xenobiotic compound. Furthermore, the inhibitory effect of oral turinabol on the cholesterol conversion has been investigated in vitro demonstrating competition of the two substrates on the active site of CYP46A1 which might be of importance for potential pathogenic effects of oral turinabol. The conversion of oral turinabol was found to be selective resulting in the formation of only one product, as shown by HPLC analysis. To produce sufficient amounts of this product for NMR analysis, a system expressing human full-length CYP46A1 and CPR on a bicistronic vector was successfully developed realizing the selective cholesterol 24-hydroxylation in E. coli in mg amounts. Using this novel whole-cell system, the conversion of oral turinabol was performed and the product of this conversion by CYP46A1 was isolated and identified as 16β-hydroxy oral turinabol by NMR.
KW - 16-Hydroxy oral turinabol
KW - Brain
KW - CYP46A1
KW - Cholesterol metabolism
KW - Dehydrochloromethyltestosterone
KW - Hydroxylase
UR - https://www.mendeley.com/catalogue/d9f9fd36-3cef-34f6-9069-0697f9303bb4/
U2 - 10.1016/j.jsbmb.2021.105927
DO - 10.1016/j.jsbmb.2021.105927
M3 - Journal articles
C2 - 34089835
SN - 0960-0760
VL - 212
JO - The Journal of Steroid Biochemistry and Molecular Biology
JF - The Journal of Steroid Biochemistry and Molecular Biology
M1 - 105927
ER -