Global Metabolomics and Targeted Steroid Profiling Reveal That Rifampin, a Strong Human PXR Activator, Alters Endogenous Urinary Steroid Markers
文摘
Activation of the pregnane X receptor (PXR) alters the expression of metabolic enzymes and transporters involved in the metabolism of xenobiotics and endobiotics. To identify endogenous biomarkers of PXR activation in humans, rifampin, a strong PXR activator, was administered to 12 healthy male subjects, and their urine was analyzed before and after rifampin administration. Ultraperformance liquid chromatography time-of-flight mass spectrometry (UPLC/QTOF鈥揗S)-based global metabolomics and gas chromatography鈥搈ass spectrometry (GC鈥揗S)-based profiling of 75 steroids were used to screen the urine samples. Global metabolomics revealed that hydroxytestosterone sulfate and glycochenodeoxycholate sulfate levels were significantly increased and that androsterone sulfate, dehydroepiandrosterone (DHEA) sulfate, and p-cresol sulfate levels were significantly decreased following rifampin administration compared with controls. Urinary steroid profiling showed that 16伪-OH-androstenedione (16伪-OH-A-dione), 16伪-OH-DHEA, 7伪-DHEA, 7尾-DHEA, and 11尾-OH-A-dione levels were increased, whereas DHEA, androsterone, etiocholanolone, estrone, 尾-cortolone, and allo-tetrahydrocortisone levels were decreased in the rifampin group. The analysis of the metabolic pathway and the metabolic ratio of steroids enabled the estimation of the induction of CYP1A/3A/7B/11B/2C and the inhibition of CYP17A/19A in response to PXR activation. These human urinary biomarkers may be useful for predicting the extent of PXR activation, monitoring the activity of DMEs, and anticipating drug鈥揹rug interactions in patients administered PXR-activating drugs.
Keywords:
untargeted and targeted metabolomics; PXR; biomarker; ultraperformance liquid chromatography time-of-flight mass spectrometry (UPLC/QTOF鈭扢S); gas chromatography鈭抦ass spectrometry (GC鈭扢S); steroid profiling