Enhanced intrinsic CYP3A4 activity in human hepatic C3A cells with optically controlled CRISPR/dCas9 activator complex

2018 ◽  
Vol 10 (12) ◽  
pp. 780-790
Author(s):  
Shuo Han ◽  
Shiruo Wei ◽  
Xuan Wang ◽  
Xu Han ◽  
Mingzhi Zhang ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Cytochrome P450 ◽  
Bioartificial Liver ◽  
Liver Development ◽  
Cytochrome P450 3A4 ◽  
Cyp3a4 Activity ◽  
Cyp3a4 Enzyme ◽  
Activator Complex

Human hepatic C3A cells have been applied in bioartificial liver development, although these cells display low intrinsic cytochrome P450 3A4 (CYP3A4) enzyme activity.

scholarly journals An Automated Multiplexed Hepatotoxicity and CYP Induction Assay Using HepaRG Cells in 2D and 3D

2017 ◽  
Vol 22 (5) ◽  
pp. 614-625 ◽  
Author(s):  
Lindsey M. Ott ◽  
Karthik Ramachandran ◽  
Lisa Stehno-Bittel
Keyword(s):  
Enzyme Activity ◽  
Cytochrome P450 ◽  
Early Stage ◽  
Three Dimensional ◽  
Atp Depletion ◽  
Drug Induced ◽  
Cyp Induction ◽  
Heparg Cells ◽  
Cyp3a4 Enzyme ◽  
2D And 3D

Drug-induced liver injury (DILI) and drug–drug interactions (DDIs) are concerns when developing safe and efficacious compounds. We have developed an automated multiplex assay to detect hepatotoxicity (i.e., ATP depletion) and metabolism (i.e., cytochrome P450 1A [CYP1A] and cytochrome P450 3A4 [CYP3A4] enzyme activity) in two-dimensional (2D) and three-dimensional (3D) cell cultures. HepaRG cells were cultured in our proprietary micromold plates and produced spheroids. HepaRG cells, in 2D or 3D, expressed liver-specific proteins throughout the culture period, although 3D cultures consistently exhibited higher albumin secretion and CYP1A/CYP3A4 enzyme activity than 2D cultures. Once the spheroid hepatic quality was assessed, 2D and 3D HepaRGs were challenged to a panel of DILI- and CYP-inducing compounds for 7 days. The 3D HepaRG model had a 70% sensitivity to liver toxins at 7 days, while the 2D model had a 60% sensitivity. In both the 2D and 3D HepaRG models, 83% of compounds were predicted to be CYP inducers after 7 days of compound exposure. Combined, our results demonstrate that an automated multiplexed liver spheroid system is a promising cell-based method to evaluate DILI and DDI for early-stage drug discovery.

Correlation Between Docetaxel Clearance and Estimated Cytochrome P450 Activity by Urinary Metabolite of Exogenous Cortisol

2000 ◽  
Vol 18 (11) ◽  
pp. 2301-2308 ◽  
Author(s):  
Noboru Yamamoto ◽  
Tomohide Tamura ◽  
Yoshikazu Kamiya ◽  
Ikuo Sekine ◽  
Hideo Kunitoh ◽  
...  
Keyword(s):  
Cytochrome P450 ◽  
Practical Method ◽  
Interpatient Variability ◽  
Cyp3a4 Activity ◽  
Time Curve ◽  
Glycoprotein P ◽  
Cytochrome P450 Activity ◽  
Free Cortisol ◽  
Cyp3a4 Enzyme ◽  
The Individual

PURPOSE: There is no simple and practical method for the estimation of the interpatient variability of cytochrome P450 (CYP3A4) enzyme activity. Cortisol is metabolized by this enzyme and excreted as 6-beta-hydroxycortisol (6β-OHF) and free-cortisol (FC) in urine, and docetaxel is also metabolized by hepatic CYP3A4 enzyme. We developed a new method for the estimation of CYP3A4 activity by measuring urinary cortisol metabolite after administration of exogenous cortisol. This study was aimed at assessing the predictability of the individual activity of CYP3A4 estimated by this method. PATIENTS AND METHODS: Thirty patients with advanced non–small-cell lung cancer were entered onto this study. Hydrocortisone 300 mg was administered intravenously, and urinary 6β-OHF and FC were measured. More than 2 days later, 60 mg/m2 of docetaxel was administered intravenously with pharmacokinetic sampling. The correlation between docetaxel pharmacokinetics and estimated interpatient variability of CYP3A4 activity with the application of our method was assessed. RESULTS: After cortisol administration, the total amount of 24-hour urinary 6β-OHF (T6β-OHF) increased about 60-fold compared with pretreatment levels, averaging 12,273 ± 4,076 μg/d (mean ± SD). Docetaxel clearance (CL) and area under the concentration-time curve averaged 24.5 ± 6.4 L/h/m2 and 2.66 ± 0.91 mg/L 8729· h, respectively. An excellent correlation between docetaxel CL and T6β-OHF was observed (r = .867). In multivariate analysis, T6β-OHF (P < .001), alpha-1-acid glycoprotein (P < .004), AST (P = .007), and age (P = .022) significantly correlated with docetaxel CL. CONCLUSION: The interpatient variability of CYP3A4 activity and docetaxel CL could be predicted by measuring T6β-OHF after cortisol administration.

Studies of the Toxicological Potential of Capsinoids, XIII: Inhibitory Effects of Capsaicin and Capsinoids on Cytochrome P450 3A4 in Human Liver Microsomes

2010 ◽  
Vol 29 (2_suppl) ◽  
pp. 22S-26S ◽  
Author(s):  
Toshiyuki Takanohashi ◽  
Mitsuyoshi Isaka ◽  
Kazuyuki Ubukata ◽  
Ryuichi Mihara ◽  
Bruce K. Bernard
Keyword(s):  
Enzyme Activity ◽  
Cytochrome P450 ◽  
Liver Microsomes ◽  
Negative Control ◽  
Cytochrome P450 3A4 ◽  
Dependent Manner ◽  
Inhibitory Effects ◽  
Microsomal Cytochrome P450 ◽  
Control Compound ◽  
Inhibition Curve

This study evaluated potential effects of a number of capsinoids (ie, capsiate, dihydrocapsiate, nordihydrocapsiate) and a single capsaicinoid (ie, capsaicin) on liver microsomal cytochrome P450 3A4-mediated midazolam 1'-hydroxylase activity. Where possible, an inhibition curve was prepared; the concentration at which enzyme activity dropped to 50% was calculated. Capsaicin clearly inhibited cytochrome P450 3A4 activity, losing 50% of the activity at 21.5 μmol/L. No enzyme inhibition was observed in the presence of capsiate, dihydrocapsiate, or nordihydrocapsiate (<100 μmol/L). Preincubation increased the capsaicin inhibitory activity against cytochrome P450 3A4 in a time-dependent manner. Enzyme activity was slightly reduced by capsiate, dihydrocapsiate, and nordihydrocapsiate to the same level as that attained with tolbutamide, the negative control compound. Capsaicin was shown to inhibit cytochrome P450 3A4, probably through a mechanism-based inhibition. In contrast, capsiate, dihydrocapsiate, and nordihydrocapsiate did not inhibit cytochrome P450 3A4 activity and were unlikely to be mechanism-based inhibitors of CYP3A4.

scholarly journals CO Binding Kinetics of Human Cytochrome P450 3A4

1995 ◽  
Vol 270 (10) ◽  
pp. 5014-5018 ◽  
Author(s):  
Aditya P. Koley ◽  
Jeroen T. M. Buters ◽  
Richard C. Robinson ◽  
Allen Markowitz ◽  
Fred K. Friedman
Keyword(s):  
Cytochrome P450 ◽  
Binding Kinetics ◽  
Cytochrome P450 3A4 ◽  
Human Cytochrome ◽  
Kinetics Of
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