Obesity is increasing worldwide, and since obesity is associated with dyslipidemia, the consumption of cholesterol-lowering pharmaceuticals has increased. The aim of this study was therefore to study potential endocrine disrupting effects of one of the world's most frequently prescribed drugs, the cholesterol-lowering drug, atorvastatin (ATO) in vitro using the H295R steroidogenesis assay and in vivo using male Sprague-Dawley rats. We analyzed all major steroids in the mammalian steroidogenesis using liquid chromatography-tandem mass spectrometry (LC-MS/MS). In vitro, ATO significantly decreased all steroids in the H295R steroidogenesis at concentrations close to human plasma Cmax values, with an IC50 value for testosterone of 0.093 ± 0.033 µM. Additionally, we determined steroid hormone levels in testis, adrenals, brain and plasma from rats after 14 days of exposure to three therapeutically relevant doses of ATO and observed pronounced decreasing steroid levels in particular in testis and adrenals but also in brain and plasma. In testis, all major steroidogenic enzymes were up-regulated, indicating autocrine and/or paracrine compensation for the decrease in steroid production by this tissue. In adrenals, StAR and CYP11A1 gene expression were decreased, whereas little effects were observed in the brain. Furthermore, we analyzed plasma LH and ACTH levels to investigate feedback via the PT and HPA axes. No effects were observed on LH levels, indicating little compensation via the PT axis. In contrast, ACTH levels increased during ATO exposure, indicating that the HPA axis to some extend compensated for the decrease in adrenal steroid production. Overall, ATO exerted pronounced effects on steroid production both in vitro and in vivo at therapeutically relevant doses. This clearly demonstrates the high potency of ATO to affect steroid homeostasis during therapeutic treatment. Further clinical and epidemiological studies should be conducted to investigate the relevance of these observations in patients treated with cholesterol-lowering pharmaceuticals.
Keywords: ACTH; Androgens; Corticosteroids; Endocrine disrupting pharmaceuticals; Progestagens; Statins; Steroid analysis.