Pregnenolone-16alpha-carbonitrile, Cytochrome P-450 inducer

Supplementary information

This supplementary information is collated from multiple sources and compiled automatically.

PXR also known as the pregnane X receptor or NR1I2 is a nuclear receptor involved in the regulation of gene expression. It plays a significant role in detoxification processes. PXR has a molecular mass of approximately 49 kDa. This receptor is primarily expressed in the liver and intestine where it mediates the induction of enzymes important in metabolizing xenobiotics and endobiotics. Notably PXR activation leads to the expression of cytochrome P450 enzymes including CYP3A4 which are essential in drug metabolism.

Biological function summary

The pregnane X receptor is an important sensor in the body's defense system against potentially harmful compounds. PXR forms a heterodimer complex with the retinoid X receptor (RXR) to exert its function. It binds to response elements in the promoter regions of target genes to regulate their transcription. This receptor is highly responsive to a variety of ligands including medications like buy tiagabine and endogenous steroids such as the pregnanolone chemical structure. Ligands binding to PXR result in the transcriptional upregulation of genes involved in several metabolic pathways.

Pathways

The pregnane X receptor has significant roles in the regulation of drug metabolism and disposition pathways. PXR activation leads to the induction of detoxifying enzymes and transporters prominently within the xenobiotic metabolism pathway. It is closely linked with CYP450 enzymes particularly CYP3A4 and the transport protein MDR1. These proteins work together to increase the metabolism and clearance of a variety of drugs and toxins thereby protecting the organism from potential harm.

PXR is associated with conditions involving drug-induced liver injury and inflammatory bowel disease. Its regulation of CYP3A4 impacts the metabolism of various drugs which can lead to altered efficacy or toxicity as seen in these conditions. Additionally PXR dysregulation has implications in liver diseases where nuclear receptors are critical for maintaining metabolic homeostasis. Interactions between PXR and other nuclear receptors like the constitutive androstane receptor (CAR) further demonstrate its involvement in hepatic health and disease.