Is the unique benzodiazepine structure interacting with CYP enzymes to affect steroid synthesis in vitro?

• Published in: The Journal of steroid biochemistry and molecular biology 2021-01, Vol.205, p.105765, Article 105765
• Main Authors: Johannsen, Malene Louise, Munkboel, Cecilie Hurup, Jørgensen, Flemming Steen, Styrishave, Bjarne
• Format: Article
• Language: English
• Subjects: Adrenal Cortex Hormones - chemistry; Adrenal Cortex Hormones - pharmacology; Adrenal Glands - drug effects; Alprazolam; Alprazolam - chemistry; Alprazolam - pharmacology; Androgens; Androgens - genetics; Benzodiazepines; Benzodiazepines - chemistry; Benzodiazepines - pharmacology; Binding mode; Complementarity; Computer applications; Corticosteroids; Diazepam; Diazepam - chemistry; Diazepam - pharmacology; Docking; Down-regulation; Endocrine disruption; Endocrine disruptors; Endocrine Disruptors - chemistry; Endocrine Disruptors - pharmacology; Enzymes; Gene expression; H295R; Heme; Humans; Hydrophobicity; Hydroxylase; Kinases; Molecular Docking Simulation; Molecular modelling; Molecular weight; Oxazepam; Oxazepam - chemistry; Oxazepam - pharmacology; Physicochemical properties; Receptors, Androgen - chemistry; Receptors, Androgen - genetics; Receptors, GABA-A - chemistry; Receptors, GABA-A - genetics; Steroid 17-alpha-Hydroxylase - antagonists & inhibitors; Steroid 17-alpha-Hydroxylase - chemistry; Steroid 17-alpha-Hydroxylase - genetics; Steroid 21-Hydroxylase - antagonists & inhibitors; Steroid 21-Hydroxylase - chemistry; Steroid 21-Hydroxylase - genetics; Steroid hormones; Steroidogenesis; Steroidogenesis in silico modelling; Steroids - biosynthesis; Steroids - chemistry; γ-Aminobutyric acid A receptors
• ISSN: 0960-0760; 1879-1220
• DOI: 10.1016/j.jsbmb.2020.105765

•Effects of 3 benzodiazepines on steroidogenesis were investigated in vitro.•In H295R cells, diazepam and oxazepam disrupted steroidogenesis by inhibiting CYP17A1.•Alprazolam exerted little effects on steroidogenesis.•Recombinant CYP17 assay confirmed that CYP17 was the main target for diazepam and oxazepam.•Benzodiazepines also affect gene transcription of steroidogenic enzymes. The aim of this project was to investigate the endocrine disrupting effects of three γ-aminobutyric acid type A receptor (GABAAR) agonists, diazepam (DZ), oxazepam (OX) and alprazolam (AL) using the steroidogenic in vitro H295R cell line assay, a recombinant CYP17A1 assay, qPCR analysis and computational modelling. Similar effects for DZ and OX on the steroidogenesis were observed in the H295R experiment at therapeutically relevant concentrations. Progestagens and corticosteroids were increased up to 10 fold and androgens were decreased indicating CYP17A1 lyase inhibition. For DZ the inhibition on both the hydroxylase and lyase was confirmed by the recombinant CYP17A1 assay, whereas OX did not appear to directly affect the recombinant CYP17A1 enzyme. Androgens were decreased when exposing the H295R cells to AL, indicating a CYP17A1 lyase inhibition. However, this was not confirmed by the recombinant CYP17A1 assay but a down-regulation in gene expression was observed for StAR and CYP17A1. The present study showed that the three investigated benzodiazepines (BZDs) are rather potent endocrine disruptors in vitro, exerting endocrine effects close the therapeutic Cmax. Both direct and indirect effects on steroidogenesis were observed, but molecular modelling indicated no direct interactions between the heme group in the steroidogenic CYP enzymes and the unique diazepin structure. In contrast, physicochemical properties such as high log P, structure and molecular weight similar to that of steroids appeared to influence the endocrine disrupting abilities of the investigated pharmaceuticals in vitro. Docking of the three BZDs in CYP17A1 and CYP21A2 confirmed that shape complementarity and hydrophobic effects seem to determine the binding modes.