Asian Science Citation Index is committed to provide an authoritative, trusted and significant information by the coverage of the most important and influential journals to meet the needs of the global scientific community.  
ASCI Database
308-Lasani Town,
Sargodha Road,
Faisalabad, Pakistan
Fax: +92-41-8815544
Contact Via Web
Suggest a Journal
 
Articles by R. J. Riley
Total Records ( 2 ) for R. J. Riley
  D. F McGinnity , G Zhang , J. R Kenny , G. A Hamilton , S Otmani , K. R Stams , S Haney , P Brassil , D. M Stresser and R. J. Riley
 

Prototypic CYP3A4 inducers were tested in a pregnane X receptor (PXR) reporter gene assay, Fa2N-4 cells, HepaRG cells, and primary human hepatocytes, along with negative controls, using CYP3A4 mRNA and activity endpoints, where appropriate. Over half of the compounds tested (14 of 24) were identified as time-dependent inhibitors of CYP3A4 and high mRNA/activity ratios (>10) were consistent with CYP3A4 time-dependent inhibition for compounds such as troleandomycin, ritonavir, and verapamil. Induction response was compared between two human donors; there was an excellent correlation in the EC50 estimates (r2 = 0.89, p < 0.001), and a weak but statistically significant correlation was noted for maximum observed induction at an optimum concentration (Emax) (r2 = 0.38, p = 0.001). Emax and EC50 estimates determined from the PXR reporter gene assay and Fa2N-4 and HepaRG cells were compared with those from hepatocytes. Overall, EC50 values generated using hepatocytes agreed with those generated in the PXR reporter gene assay (r2 = 0.85, p < 0.001) and Fa2N-4 (r2 = 0.65, p < 0.001) and HepaRG (r2 = 0.99, p < 0.001) cells. However, Emax values generated in hepatocytes were only significantly correlated to those determined in Fa2N-4 (r2 = 0.33, p = 0.005) and HepaRG cells (r2 = 0.79, p < 0.001). "Gold standard" cytochrome P450 induction data can be generated using primary human hepatocytes, but a restricted, erratic supply and interdonor variability somewhat restrict routine application within a drug discovery setting. HepaRG cells are a valuable recent addition to the armory of in vitro tools for assessing CYP3A4 induction and seem to be an excellent surrogate of primary cells.

  D. F McGinnity , G Zhang , J. R Kenny , G. A Hamilton , S Otmani , K. R Stams , S Haney , P Brassil , D. M Stresser and R. J. Riley
 

Prototypic CYP3A4 inducers were tested in a pregnane X receptor (PXR) reporter gene assay, Fa2N-4 cells, HepaRG cells, and primary human hepatocytes, along with negative controls, using CYP3A4 mRNA and activity endpoints, where appropriate. Over half of the compounds tested (14 of 24) were identified as time-dependent inhibitors of CYP3A4 and high mRNA/activity ratios (>10) were consistent with CYP3A4 time-dependent inhibition for compounds such as troleandomycin, ritonavir, and verapamil. Induction response was compared between two human donors; there was an excellent correlation in the EC50 estimates (r2 = 0.89, p < 0.001), and a weak but statistically significant correlation was noted for maximum observed induction at an optimum concentration (Emax) (r2 = 0.38, p = 0.001). Emax and EC50 estimates determined from the PXR reporter gene assay and Fa2N-4 and HepaRG cells were compared with those from hepatocytes. Overall, EC50 values generated using hepatocytes agreed with those generated in the PXR reporter gene assay (r2 = 0.85, p < 0.001) and Fa2N-4 (r2 = 0.65, p < 0.001) and HepaRG (r2 = 0.99, p < 0.001) cells. However, Emax values generated in hepatocytes were only significantly correlated to those determined in Fa2N-4 (r2 = 0.33, p = 0.005) and HepaRG cells (r2 = 0.79, p < 0.001). "Gold standard" cytochrome P450 induction data can be generated using primary human hepatocytes, but a restricted, erratic supply and interdonor variability somewhat restrict routine application within a drug discovery setting. HepaRG cells are a valuable recent addition to the armory of in vitro tools for assessing CYP3A4 induction and seem to be an excellent surrogate of primary cells.

 
 
 
Copyright   |   Desclaimer   |    Privacy Policy   |   Browsers   |   Accessibility