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08/09/2019

What is a P-gp inducer?

What is a P-gp inducer?

Inducers include rifampicin and St John’s wort. P-glycoprotein has a very wide substrate spectrum similar to CYP3A4. It is involved in the transport of drugs from different drug classes including: antineoplastic drugs e.g. docetaxel, etoposide, vincristine. calcium channel blockers e.g. amlodipine.

What is the function of P-glycoprotein?

P-glycoprotein, the most extensively studied ATP-binding cassette (ABC) transporter, functions as a biological barrier by extruding toxins and xenobiotics out of cells. In vitro and in vivo studies have demonstrated that P-glycoprotein plays a significant role in drug absorption and disposition.

Does phenobarbital induce P-gp?

Phenytoin, phenobarbital, carbamazepine, and valproic acid induced the overexpression of Pgp in astrocytes in a dose- and time-dependent manner.

What is P-glycoprotein role in multi drug resistant cancers?

P-glycoprotein (P-gp) is a well-identified membrane transporter with capability to efflux drug molecules out of the cancer cell leading to reduced efficiency of chemotherapy. Cancer cells upregulate P-gp expression as an adaptive response to evade chemotherapy mediated cell death.

Which CYP does phenobarbital induce?

Enzyme-inducing drugs and their cytochrome (CYP) targets

CYP
1A2 2B6 2C19
Phenobarbital Phenobarbital Norethindrone
Ritonavir Ritonavir Rifampicin
Rifampicin Rifampicin St John’s Wort

What enzymes does phenobarbital induce?

The most significant aspect of the metabolism of barbiturates (e.g., phenobarbital, thiopental, methohexital) is their effect on the hepatic microsomal enzyme system (cytochrome P450 (CYP) enzymes). These effects are dependent on the duration of exposure to the barbiturate.

How are inhibitors and inducers of P-gp drug efflux different?

Inhibitors of the P-gp drug efflux pump (also known as P-gp multidrug resistance transporter) listed above may increase serum concentrations of drugs that are substrates of P-gp, whereas inducers of P-gp drug efflux may decrease serum concentrations of substrates of P-gp.

Are there any inhibitors or inducers of P-glycoprotein?

Inhibitors and inducers of P-glycoprotein (P-gp) drug efflux pump (P-gp multidrug resistance transporter) Inhibitors of P-gp. Amiodarone. Neratinib. Azithromycin (systemic) Ombitasvir-paritaprevir-ritonavir (Technivie)*. Capmatinib. Osimertinib.

How is P-gp related to multidrug resistance?

Members of the MDR/TAP subfamily are involved in multidrug resistance. P-gp is an ATP-dependent drug efflux pump for xenobiotic compounds with broad substrate specificity. It is responsible for decreased drug accumulation in multidrug-resistant cells and often mediates the development of resistance to anticancer drugs.

How are activators and repressors related to gene regulation?

Repressor binding physically blocks RNA polymerase from transcribing structural genes. Conversely, an activator is a transcription factor that increases the transcription of a gene in response to an external stimulus by facilitating RNA polymerase binding to the promoter.