PXR acts as a xenobiotic sensor, detecting the presence of foreign substances in the body. Upon activation by ligands, PXR binds to specific response elements in the DNA, leading to the transcription of genes encoding drug-metabolizing enzymes such as Cytochrome P450 enzymes (e.g., CYP3A4). This enhances the metabolic clearance of drugs and reduces their potential toxicity. PXR's ability to regulate these enzymes underscores its significance in pharmacokinetics.
