What happens when P-glycoprotein is induced?

In the gut, P-glycoprotein pumps drugs back into the lumen, decreasing their absorption. Drugs which induce P-glycoprotein, such as rifampicin, can reduce the bioavailability of some other drugs. Inhibitors of P-glycoprotein, such as verapamil, increase the bioavailability of susceptible drugs.

What is the role 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.

Is P-glycoprotein an active transporter?

P-glycoprotein (P-gp) is an ATP-binding cassette (ABC) transporter responsible for the multidrug resistance (MDR) phenotype when overproduced in the plasma membrane of tumor cells (1). P-gp exhibits an ATP hydrolysis activity, coupled to the efflux of a variety of hydrophobic molecules (2, 3).

What is a P-glycoprotein inhibitor?

P-gp is overexpressed on the surface of cancer cells and prevents drug accumulation inside the tumor, acting as the efflux pump. It extrudes anticancer drugs before they can reach the intended target. Further, it often mediates the development of resistance of the cells to anticancer drugs.

Is P-glycoprotein the same as MDR1?

MDR1, more commonly referred to as P-gp or P-glycoprotein, is an efflux transporter that serves two major drug transport functions. Its role in modulating the tissue distribution of drugs is well established, particularly with respect to CNS exposure.

Does azithromycin inhibit P-glycoprotein?

Macrolides: Erythromycin, Azithromycin, and Clarithromycin The FDA approved macrolide antibiotics (erythromycin, azithromycin, and clarithromycin) were all reported as p-gp inhibitors. This has been supported by many studies in the literature (64–66).

What type of transport is P-glycoprotein?

Human P-glycoprotein (ABCB1) is a primary multidrug transporter located in plasma membranes, that, utilizes the energy of ATP hydrolysis to pump toxic xenobiotics out of cells. P-glycoprotein employs a most unusual molecular mechanism to perform this drug transport function.

Does cyclosporine inhibit P-gp?

Cyclosporine and sirolimus are P-glycoprotein (Pgp) substrates. Pgp expression and function were confirmed in HRECs and cyclosporine and sirolimus were shown to be Pgp inhibitors in this model. Verapamil-induced inhibition of Pgp led to a significant increase in cellular concentration of cyclosporine (P<0.05).