Cannabis (Cannabis sativa)
In Vitro Inhibition of Carboxylesterase 1 by Major Cannabinoids and Selected Metabolites CSV JSON

The escalating use of medical cannabis and significant recreational use of cannabis in recent years has led to a higher potential for metabolic interactions between cannabis or one or more of its components and concurrently used medications. Although there have been a significant number of in vitro and in vivo assessments of the effects of cannabis on cytochrome P450 and UDP-glucuronosyltransferase enzyme systems, there is limited information regarding the effects of cannabis on the major hepatic esterase, carboxylesterase 1 (CES1). In this study, we investigated the in vitro inhibitory effects of the individual major cannabinoids and metabolites Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), cannabinol (CBN), 11-nor-THC-carboxylic acid, and 11-hydroxy-THC on CES1 activity. S9 fractions from human embryonic kidney 293 cells stably expressing CES1 were used in the assessment of cannabinoid inhibitory effects. THC, CBD, and CBN each exhibited substantial inhibitory potency, and were further studied to determine their mechanism of inhibition and kinetic parameters. The inhibition of CES1 by THC, CBD, and CBN was reversible and appears to proceed through a mixed competitivenoncompetitive mechanism. The inhibition constant (Ki) values for THC, CBD, and CBN inhibition were 0.541, 0.974, and 0.263 mM (0.170, 0.306, and 0.0817 mg/ml), respectively. Inhibition potency was increased when THC, CBD, and CBN were combined. Compared with the potential unbound plasma concentrations attainable clinically, the Ki values suggest a potential for clinically significant inhibition of CES1 by THC and CBD. CBN, however, is expected to have a limited impact on CES1. Carefully designed clinical studies are warranted to establish the clinical significance of these in vitro findings.

Cannabis (Cannabis sativa)

30833288

1 . Evaluation of Time-Dependent CES1 Inhibition by CBD (30 min) (id=NPDI-sciDeA)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used —

Not provided

oseltamivir phosphate

cannabidiol

oseltamivir acid

  • CES1

Cell fraction Human kidney S9 fraction

Results

IC50 pre-incubation 0 min (A) = 7.73 µM
IC50 pre-incubation 30 min (B) = 12.1 µM
B/A = 1.57

Sample Compound measured Value Measurement Study sequence Additional information N replicates

Experimental Conditions

20 µg/mL

Commercially available

100 µL

15 min

1 mM

30 min

30 min

0 - 50 µg/mL

2 . Evaluation of Time-Dependent CES1 Inhibition by CBD (0 min) (id=NPDI-gAcr3g)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used —

Not provided

oseltamivir phosphate

cannabidiol

oseltamivir acid

  • CES1

Cell fraction Human kidney S9 fraction

Results

IC50 pre-incubation 0 min (A) = 7.73 µM
IC50 pre-incubation 30 min (B) = 12.1 µM
B/A = 1.57

Sample Compound measured Value Measurement Study sequence Additional information N replicates

Experimental Conditions

20 µg/mL

Commercially available

100 µL

15 min

1 mM

30 min

0 min

0 - 50 µg/mL

3 . Inhibition of CES1 by CBD (id=NPDI-a3nUTg)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used —

90% inhibition

oseltamivir phosphate

cannabidiol

oseltamivir acid

  • CES1

Cell fraction Human kidney S9 fraction

Results

Table 2

Sample Compound measured Value Measurement Study sequence Additional information N replicates

Experimental Conditions

20 microG/ml

Commercially available

100 µL

15 min

0, 100, 500, 1000, 2500, 5000 µM

0 - 10 µg/mL

4 . Evaluation of Time-Dependent CES1 Inhibition by CBN (0 min) (id=NPDI-2KocMg)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used —

Not provided

oseltamivir phosphate

cannabinol

oseltamivir acid

  • CES1

Cell fraction Human kidney S9 fraction

Results

IC50 pre-incubation 0 min (A) = 4.03 µM
IC50 pre-incubation 30 min (B) = 8.51 µM
B/A = 2.11

Sample Compound measured Value Measurement Study sequence Additional information N replicates

Experimental Conditions

20 µg/mL

Commercially available

100 µL

15 min

1 mM

30 min

0 min

0 - 50 µg/mL

5 . Inhibition of CES1 by CBN (id=NPDI-LI0O-A)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used —

90% inhibition

oseltamivir phosphate

cannabinol

oseltamivir acid

  • CES1

Cell fraction Human kidney S9 fraction

Results

Table 2

Sample Compound measured Value Measurement Study sequence Additional information N replicates

Experimental Conditions

20 microG/ml

Commercially available

100 µL

15 min

0, 100, 500, 1000, 2500, 5000 µM

0 - 10 µg/mL

6 . Evaluation of Time-Dependent CES1 Inhibition by CBN (30 min) (id=NPDI--0E9EQ)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used —

Not provided

oseltamivir phosphate

cannabinol

oseltamivir acid

  • CES1

Cell fraction Human kidney S9 fraction

Results

IC50 pre-incubation 0 min (A) = 4.03 µM
IC50 pre-incubation 30 min (B) = 8.51 µM
B/A = 2.11

Sample Compound measured Value Measurement Study sequence Additional information N replicates

Experimental Conditions

20 µg/mL

Commercially available

100 µL

15 min

1 mM

30 min

30 min

0 - 50 µg/mL

7 . Evaluation of Time-Dependent CES1 Inhibition by THC (0 min) (id=NPDI-t5Bygg)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used —

Not provided

oseltamivir phosphate

oseltamivir acid

  • CES1

Cell fraction Human kidney S9 fraction

Results

IC50 pre-incubation 0 min (A) = 3.91 µM
IC50 pre-incubation 30 min (B) = 11.2 µM
B/A = 2.85

Sample Compound measured Value Measurement Study sequence Additional information N replicates

Experimental Conditions

20 µg/mL

Commercially available

100 µL

15 min

1 mM

30 min

0 min

0 - 50 µg/mL

8 . Inhibition of CES1 by THC (id=NPDI-AIeEmg)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used —

90% inhibition

oseltamivir phosphate

oseltamivir acid

  • CES1

Cell fraction Human kidney S9 fraction

Results

Table 2

Sample Compound measured Value Measurement Study sequence Additional information N replicates

Experimental Conditions

20 microG/ml

Commercially available

100 µL

15 min

0, 100, 500, 1000, 2500, 5000 µM

0 - 10 µg/mL

9 . Evaluation of Time-Dependent CES1 Inhibition by THC (30 min) (id=NPDI-8d0Lug)

In Vitro Enzyme Inhibition Experiment

Inhibition was detected.  Cutoff used —

Not provided

oseltamivir phosphate

oseltamivir acid

  • CES1

Cell fraction Human kidney S9 fraction

Results

IC50 pre-incubation 0 min (A) = 3.91 µM
IC50 pre-incubation 30 min (A) = 11.2 µM
B/A = 2.85

Sample Compound measured Value Measurement Study sequence Additional information N replicates

Experimental Conditions

20 µg/mL

Commercially available

100 µL

15 min

1 mM

30 min

30 min

0 - 50 µg/mL