Discovery of 4-acetyl-3-(4-fluorophenyl)-1-(p-tolyl)-5-methylpyrrole as a dual inhibitor of human P-glycoprotein and Staphylococcus aureus Nor A efflux pump

Org Biomol Chem. 2015 May 21;13(19):5424-31. doi: 10.1039/c5ob00246j.

Abstract

Polysubstituted pyrrole natural products, lamellarins, are known to overcome multi-drug resistance in cancer via the inhibition of p-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) efflux pumps. Herein, a series of simplified polysubstituted pyrroles, prepared via a one-pot domino protocol, were screened for P-gp inhibition in P-gp overexpressing human adenocarcinoma LS-180 cells using a rhodamine 123 efflux assay. Several compounds showed the significant inhibition of P-gp at 50 μM, as indicated by increase in the intracellular accumulation of Rh123 in LS-180 cells. Furthermore, pyrrole 5i decreased the efflux of digoxin, a FDA approved P-gp substrate in MDCK-MDR1 cells with an IC50 of 11.2 μM. In in vivo studies, following the oral administration of a P-gp substrate drug, rifampicin, along with compound , the Cmax and AUC0-∞ of rifampicin was enhanced by 31% and 46%, respectively. All the compounds were then screened for their ability to potentiate ciprofloxacin activity via the inhibition of Staphylococcus aureus Nor A efflux pump. Pyrrole showed the significant inhibition of S. aureus Nor A efflux pump with 8- and 4-fold reductions in the MIC of ciprofloxacin at 50 and 6.25 μM, respectively. The molecular docking studies of compound with the human P-gp and S. aureus Nor A efflux pump identified its plausible binding site and key interactions. Thus, the results presented herein strongly indicate the potential of this scaffold for its use as multi-drug resistance reversal agent or bioavailability enhancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily B / antagonists & inhibitors*
  • ATP Binding Cassette Transporter, Subfamily B / metabolism
  • Administration, Oral
  • Animals
  • Bacterial Proteins / antagonists & inhibitors*
  • Bacterial Proteins / metabolism
  • Binding Sites
  • Biological Transport / drug effects
  • Caco-2 Cells
  • Ciprofloxacin / pharmacology
  • Coumarins / chemical synthesis
  • Coumarins / pharmacology
  • Dogs
  • Ethidium / metabolism
  • Humans
  • Madin Darby Canine Kidney Cells
  • Mice, Inbred BALB C
  • Models, Molecular
  • Multidrug Resistance-Associated Proteins / antagonists & inhibitors*
  • Multidrug Resistance-Associated Proteins / metabolism
  • Pyrroles / chemical synthesis
  • Pyrroles / chemistry
  • Pyrroles / pharmacology*
  • Rifampin / administration & dosage
  • Rifampin / pharmacokinetics
  • Staphylococcus aureus / metabolism*

Substances

  • 4-acetyl-3-(4-fluorophenyl)-1-(p-tolyl)-5-methylpyrrole
  • ATP Binding Cassette Transporter, Subfamily B
  • Bacterial Proteins
  • Coumarins
  • Multidrug Resistance-Associated Proteins
  • Pyrroles
  • NorA protein, Staphylococcus
  • Ciprofloxacin
  • Ethidium
  • Rifampin