How Uremic Toxins Alter Atorvastatin Disposition: Molecular Mechanisms of Inhibition of the Enzyme CYP3A4

Abstract

Background: In uremic patients, the accumulation of gut-derived protein-bound uremic toxins (PBUTs) induces changes in the microenvironment of the patients, leading to changes in the elimination pattern of drugs. Aims: To assess ways in which PBUTs alter the CYP450 enzymes in hepatocytes as well as the possible effects of specific PBUTs on the metabolism and excretion of atorvastatin (ATV). Study Design: An experimental study. Methods: The experimental group was treated with long-term MHD for > 3 months, estimated-glomerular filtration rate (e-GFR) 50% inhibition. Meanwhile, the protein expression of CYP3A4 was downregulated after incubation with US, IS, and HA (p < 0.01). The excretion of ATV was also inhibited by 59.24% and 71.95% after incubation with IS and HA, respectively. The effects of uremic toxins on PXR/NF-κB mRNA and protein expression elucidated that PBUTs can inhibit ATV uptake and metabolism by exerting inhibitory effects on CYP3A4 through the PXR/NF-κB signaling pathway. Conclusion: ATV metabolism could be significantly altered in the presence of uremic toxins, suggesting a downregulated effect on the ATV uptake, possibly through Oatp1b1, and also on the activity of CYP3A4 through the PXR/NF-κB signaling pathway.