A cocktail probe approach to evaluate the effect of hormones on the expression and activity of CYP enzymes in human hepatocytes with conditions simulating late stage of pregnancy

A simple HPLC method for the determination of plasma progesterone levels in the third trimester of human pregnancy

Progesterone is a steroid hormone primarily associated with pregnancy. A simple, rapid, and reliable high-performance liquid chromatography (HPLC) method has been developed and validated for the quantification of progesterone in human plasma. The method consists of a simple liquid-liquid extraction of progesterone and internal standard (estriol) from human plasma using a mixture of hexane and diethyl ether. The chromatographic determination of progesterone was performed using an acetonitrile-water (70:30, v/v) mobile phase with a C18 reversed-phase column. The method achieved an extraction recovery of greater than 96.4% from spiked plasma samples. Intra- and inter-day precision were generally acceptable, with relative SD% less than ≤6.60% and accuracy (relative error %) better than 3.64%. The developed and validated method was used to successfully quantify progesterone levels in plasma samples collected from women during the third trimester of pregnancy. Furthermore, a statistical comparison was conducted between progesterone concentrations in plasma samples obtained from 2 groups of pregnant women: group 1 (n = 9) at 30-35 weeks and group 2 (n = 9) at 36-41 weeks. The developed and validated HPLC method described in this study enables the successful determination of progesterone in human plasma, offering advantages such as shorter analysis time, simplicity, cost-effectiveness, and potential routine use during pregnancy.

The effect of pregnancy-related hormones on hepatic transporters: studies with premenopausal human hepatocytes

Introduction

Pregnancy results in significant changes in drug pharmacokinetics (PK). While previous studies have elucidated the impact of pregnancy-related hormones (PRH) on mRNA or protein expression and activity of major hepatic metabolizing enzymes, their effect on hepatic drug transporters remains largely unexplored. Therefore, we investigated the effect of a cocktail of PRH on the mRNA expression and activity of hepatic transporters.

Methods

Plated human hepatocytes (PHH) from 3 premenopausal donors were incubated, in triplicate, for 72 h, with vehicle (DMSO < 0.01%), rifampin (10 μM; positive control) or a cocktail of PRH consisting of estrone, estradiol, estriol, estetrol, progesterone, cortisol, testosterone, oxytocin, and placental growth hormone. The PRH concentrations replicated 0.1×, 1×, or 10× of the plasma concentrations of these hormones observed during each of the three trimesters of pregnancy. After treatment, mRNA expression (quantified by qPCR) of hepatic influx and efflux transporters as well as the activity of influx transporters was quantified (uptake of a selective substrate ± corresponding transporter inhibitor). The data were expressed relative to that in the control (vehicle) group. Significance was evaluated by ANOVA (followed by Dunn's multiple comparisons) or unpaired t-test when the within-lot data were analyzed, or repeated measures ANOVA (followed by Dunn's multiple comparisons) or paired t-test when data from all 3 lots were analyzed (p < 0.05).

Results and Discussion

In general, a) PRH cocktails significantly induced transporter mRNA expression in the following order OAT2 ≈ NTCP ≈ OCT1 > OATP2B1 and repressed mRNA expression in the following order OATP1B3 > OATP1B1; b) these changes translated into significant induction of OAT2 (T1-T3) and NTCP (T2-T3, in only two lots) activity at the 1× PRH concentration. Compared with the influx transporters, the induction of mRNA expression of efflux transporters was modest, with mRNA expression of MRP2 and BSEP being induced the most.

Conclusion

Once these data are verified through in vivo probe drug PK studies in pregnancy, they can be populated into physiologically based pharmacokinetic (PBPK) models to predict, for all trimesters of pregnancy, transporter-mediated clearance of any drug that is a substrate of the affected transporters.

The impact of pregnancy and associated hormones on the pharmacokinetics of Δ9-tetrahydrocannabinol

INTRODUCTION

(-)-Δ9-tetrahydrocannabinol (THC) is the main psychoactive component of cannabis. Cannabis is the most widely used drug of abuse by pregnant individuals, but its maternal-fetal safety is still unclear. The changes in THC disposition during pregnancy may affect THC safety and pharmacology.

AREAS COVERED

This review summarizes the current literature on THC metabolism and pharmacokinetics in humans. It provides an analysis of how hormonal changes during pregnancy may alter the expression of cannabinoid metabolizing enzymes and THC and its metabolite pharmacokinetics. THC is predominately (>70%) cleared by hepatic metabolism to its psychoactive active metabolite, 11-OH-THC by cytochrome P450 (CYP) 2C9 and to other metabolites (<30%) by CYP3A4. Other physiological processes that change during pregnancy and may alter cannabinoid disposition are also reviewed.

EXPERT OPINION

THC and its metabolites disposition likely change during pregnancy. Hepatic CYP2C9 and CYP3A4 are induced in pregnant individuals and in vitro by pregnancy hormones. This induction of CYP2C9 and CYP3A4 is predicted to lead to altered THC and 11-OH-THC disposition and pharmacodynamic effects. More in vitro studies of THC metabolism and induction of the enzymes metabolizing cannabinoids are necessary to improve the prediction of THC pharmacokinetics in pregnant individuals.