Green Tea (Camellia sinensis) 19124972
Effects of green tea catechins on cytochrome P450 2B6, 2C8, 2C19, 2D6 and 3A activities in human liver and intestinal microsomes CSV JSON

The effects of green tea catechins on the main drug-metabolizing enzymatic system, cytochrome P450 (CYP), have not been fully elucidated. The objective of the present study was to evaluate the effects of green tea extract (GTE, total catechins 86.5%, w/w) and (-)-epigallocatechin-3-gallate (EGCG) on the activities of CYP2B6, CYP2C8, CYP2C19, CYP2D6 and CYP3A in vitro, using pooled human liver and intestinal microsomes. Bupropion hydroxylation, amodiaquine N-deethylation, (S)-mephenytoin 4'-hydroxylation, dextromethorphan O-demethylation and midazolam 1'-hydroxylation were assessed in the presence or absence of various concentrations of GTE and EGCG to test their effects on CYP2B6, CYP2C8, CYP2C19, CYP2D6 and CYP3A activities, respectively. Each metabolite was quantified using UPLC/ESI-MS, and the inhibition kinetics of GTE and EGCG on CYP enzymes was analyzed. In human liver microsomes, IC50 values of GTE were 5.9, 4.5, 48.7, 25.1 and 13.8 µg/mL, for CYP2B6, CYP2C8, CYP2C19, CYP2D6 and CYP3A, respectively. ECGC also inhibited these CYP isoforms with properties similar to those of GTE, and produced competitive inhibitions against CYP2B6 and CYP2C8, and noncompetitive inhibition against CYP3A. In human intestinal microsomes, IC50 values of GTE and EGCG for CYP3A were 18.4 µg/mL and 31.1 µM, respectively. EGCG moderately inhibited CYP3A activity in a noncompetitive manner. These results suggest that green tea catechins cause clinically relevant interactions with substrates for CYP2B6 and CYP2C8 in addition to CYP3A.

1 . Inhibition of CYP2C8 by (-)-Epigallocatechin Gallate in HLM (IC50 Determination) (id=NPDI-Hh_vaQ)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used — IC50 determination

amodiaquine

N-desethylamodiaquine

  • CYP2C8 4306333

Cell fraction Pooled human liver microsomes -7999662

Results

Compound measured Measurement Value Study sequence Additional information N replicates

Experimental Conditions

0.1 mg/mL

Commercially available

100 µL

20 min

NADPH

Not available

Not available

2.6 µM

1-218 µM

2 . Inhibition of CYP2C8 by (-)-Epigallocatechin Gallate in HLM (Ki Determination) (id=NPDI-rnQE5Q)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used — Ki determination

amodiaquine

N-desethylamodiaquine

  • CYP2C8 4306333

Cell fraction Pooled human liver microsomes -7999662

Results

Compound measured Measurement Value Study sequence Additional information N replicates

Experimental Conditions

0.1 mg/mL

Commercially available

100 µL

20 min

NADPH

Not available

Not available

1.3-5.2 µM

1-218 µM

3 . Inhibition of CYP2B6 by (-)-Epigallocatechin Gallate in HLM (IC50 Determination) (id=NPDI-KMW0mA)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used — IC50 determination

bupropion 750982

hydroxybupropion 4037950

  • CYP2B6 4308333

Cell fraction Pooled human liver microsomes -7999662

Results

Compound measured Measurement Value Study sequence Additional information N replicates

Experimental Conditions

0.1 mg/mL

Commercially available

100 µL

20 min

NADPH

Not available

Not available

62 µM

1-218 µM

4 . Inhibition of CYP2B6 by (-)-Epigallocatechin Gallate in HLM (Ki Determination) (id=NPDI-oFLPrw)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used — Ki determination

bupropion 750982

hydroxybupropion 4037950

  • CYP2B6 4308333

Cell fraction Pooled human liver microsomes -7999662

Results

Compound measured Measurement Value Study sequence Additional information N replicates

Experimental Conditions

0.1 mg/mL

Commercially available

100 µL

20 min

NADPH

Not available

Not available

31-124 µM

1-218 µM

5 . Inhibition of CYP2D6 by (-)-Epigallocatechin Gallate in HLM (IC50 Determination) (id=NPDI-P8wXLQ)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used — IC50 determination

dextromethorphan 1119510

dextrorphan 4349487

  • CYP2D6 4173631

Cell fraction Pooled human liver microsomes -7999662

Results

Compound measured Measurement Value Study sequence Additional information N replicates

Experimental Conditions

0.1 mg/mL

Commercially available

100 µL

10 min

NADPH

Not available

Not available

2.7 µM

1-218 µM

6 . Inhibition of CYP2D6 by (-)-Epigallocatechin Gallate in HLM (Ki Determination) (id=NPDI-kN7saQ)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used — Ki determination

dextromethorphan 1119510

dextrorphan 4349487

  • CYP2D6 4173631

Cell fraction Pooled human liver microsomes -7999662

Results

Compound measured Measurement Value Study sequence Additional information N replicates

Experimental Conditions

0.1 mg/mL

Commercially available

100 µL

10 min

NADPH

Not available

Not available

1.3-5.4 µM

1-218 µM

7 . Inhibition of CYP2C19 by (-)-Epigallocatechin Gallate in HLM (IC50 Determination) (id=NPDI-cXHH7g)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used — IC50 determination

mephenytoin, (S)-

4-hydroxymephenytoin, (S)-

  • CYP2C19 4311137

Cell fraction Pooled human liver microsomes -7999662

Results

Compound measured Measurement Value Study sequence Additional information N replicates

Experimental Conditions

0.2 mg/mL

Commercially available

100 µL

40 min

NADPH

Not available

Not available

29 µM

1-218 µM

8 . Inhibition of CYP2C19 by (-)-Epigallocatechin Gallate in HLM (Ki Determination) (id=NPDI-YR9AgQ)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used — Ki determination

mephenytoin, (S)-

4-hydroxymephenytoin, (S)-

  • CYP2C19 4311137

Cell fraction Pooled human liver microsomes -7999662

Results

Compound measured Measurement Value Study sequence Additional information N replicates

Experimental Conditions

0.2 mg/mL

Commercially available

100 µL

40 min

NADPH

Not available

Not available

14.5-58 µM

1-218 µM

9 . Inhibition of CYP3A by (-)-Epigallocatechin Gallate in HLM (IC50 Determination) (id=NPDI-6x_uKQ)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used — IC50 determination

midazolam 708298

1'-hydroxymidazolam

  • CYP3A4 4306811

Cell fraction Pooled human liver microsomes -7999662

Results

Compound measured Measurement Value Study sequence Additional information N replicates

Experimental Conditions

0.1 mg/mL

Commercially available

100 µL

5 min

NADPH

Not available

Not available

1.7 µM

1-218 µM

10 . Inhibition of CYP3A by (-)-Epigallocatechin Gallate in HLM (Ki Determination) (id=NPDI-LZlNyQ)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used — Ki determination

midazolam 708298

1'-hydroxymidazolam

  • CYP3A4 4306811

Cell fraction Pooled human liver microsomes -7999662

Results

Compound measured Measurement Value Study sequence Additional information N replicates

Experimental Conditions

0.1 mg/mL

Commercially available

100 µL

5 min

NADPH

Not available

Not available

1.5-6.0 µM

1-218 µM

11 . Inhibition of CYP3A by (-)-Epigallocatechin Gallate in HIM (IC50 Determination) (id=NPDI-FMvj7w)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used — IC50 determination

midazolam 708298

1'-hydroxymidazolam

  • CYP3A4 4306811

Cell fraction Pooled human intestinal microsomes -7999663

Results

Compound measured Measurement Value Study sequence Additional information N replicates

Experimental Conditions

0.2 mg/mL

Commercially available

100 µL

5 min

NADPH

Not available

Not available

3.0 µM

1-218 µM

12 . Inhibition of CYP3A by (-)-Epigallocatechin Gallate in HIM (Ki Determination) (id=NPDI-AIlkaw)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used — Ki determination

midazolam 708298

1'-hydroxymidazolam

  • CYP3A4 4306811

Cell fraction Pooled human intestinal microsomes -7999663

Results

Compound measured Measurement Value Study sequence Additional information N replicates

Experimental Conditions

0.2 mg/mL

Commercially available

100 µL

5 min

NADPH

Not available

Not available

0.8-3.4 µM

1-218 µM