Effect of type 2 diabetes mellitus on the pharmacokinetics and transplacental transfer of nifedipine in hypertensive pregnant women

Mechanistic Framework to Predict Maternal-Placental-Fetal Pharmacokinetics of Nifedipine Employing Physiologically Based Pharmacokinetic Modeling Approach

Nifedipine is used for treating mild to severe hypertension and preventing preterm labor in pregnant women. Nevertheless, concerns about nifedipine fetal exposure and safety are always raised. The aim of this study was to develop and validate a maternal-placental-fetal nifedipine physiologically based pharmacokinetic (PBPK) model and apply the model to predict maternal, placental, and fetal exposure to nifedipine at different pregnancy stages. A nifedipine PBPK model was verified with nonpregnant data and extended to the pregnant population after the inclusion of the fetoplacental multicompartment model that accounts for the placental tissue and different fetal organs within the Simcyp Simulator version 22. Model parametrization involved scaling nifedipine transplacental clearance based on Caco-2 permeability, and fetal hepatic clearance was obtained from in vitro to in vivo extrapolation encompassing cytochrome P450 3A7 and 3A4 activities. Predicted concentration profiles were compared with in vivo observations and the transplacental transfer results were evaluated using 2-fold criteria. The PBPK model predicted a mean cord-to-maternal plasma ratio of 0.98 (range, 0.86-1.06) at term, which agrees with experimental observations of 0.78 (range, 0.59-0.93). Predicted nifedipine exposure was 1.4-, 2.0-, and 3.0-fold lower at 15, 27, and 39 weeks of gestation when compared with nonpregnant exposure, respectively. This innovative PBPK model can be applied to support maternal and fetal safety assessment for nifedipine at various stages of pregnancy.

Exploring the role of gut microbiota in advancing personalized medicine

Ongoing extensive research in the field of gut microbiota (GM) has highlighted the crucial role of gut-dwelling microbes in human health. These microbes possess 100 times more genes than the human genome and offer significant biochemical advantages to the host in nutrient and drug absorption, metabolism, and excretion. It is increasingly clear that GM modulates the efficacy and toxicity of drugs, especially those taken orally. In addition, intra-individual variability of GM has been shown to contribute to drug response biases for certain therapeutics. For instance, the efficacy of cyclophosphamide depends on the presence of Enterococcus hirae and Barnesiella intestinihominis in the host intestine. Conversely, the presence of inappropriate or unwanted gut bacteria can inactivate a drug. For example, dehydroxylase of Enterococcus faecalis and Eggerthella lenta A2 can metabolize L-dopa before it converts into the active form (dopamine) and crosses the blood-brain barrier to treat Parkinson's disease patients. Moreover, GM is emerging as a new player in personalized medicine, and various methods are being developed to treat diseases by remodeling patients' GM composition, such as prebiotic and probiotic interventions, microbiota transplants, and the introduction of synthetic GM. This review aims to highlight how the host's GM can improve drug efficacy and discuss how an unwanted bug can cause the inactivation of medicine.

Pharmacokinetics of the most commonly used antihypertensive drugs throughout pregnancy methyldopa, labetalol, and nifedipine: a systematic review

Purpose

Antihypertensive drugs are among the most prescribed drugs during pregnancy. Methyldopa, labetalol, and nifedipine have been perceived safe to use during pregnancy and are therefore recommended in international guidelines for treatment of hypertension. In this review, we provide a complete overview of what is known on the pharmacokinetics (PK) of the antihypertensive drugs methyldopa, labetalol, and nifedipine throughout pregnancy.

Methods

A systematic search was performed to retrieve studies on the PK of methyldopa, labetalol, and nifedipine used throughout pregnancy. The search was restricted to English and original studies. The systematic search was conducted on July 27, 2021, in Embase, Medline Ovid, Web of Science, Cochrane Library, and Google Scholar. Keywords were methyldopa, labetalol, nifedipine, pharmacokinetics, pregnancy, and placenta.

Results

A total of 1459 unique references were identified of which title and abstract were screened. Based on this screening, 67 full-text papers were assessed, to retain 30 PK studies of which 2 described methyldopa, 12 labetalol, and 16 nifedipine. No fetal accumulation is found for any of the antihypertensive drugs studied.

Conclusion

We conclude that despite decades of prescribing methyldopa, labetalol, and nifedipine throughout pregnancy, descriptions of their PK during pregnancy are hampered by a large heterogeneity in the low number of available studies. Aiming for evidence-based and personalized dosing of antihypertensive medication in the future, further studies on the relationship of both PK and pharmacodynamics (including the optimal blood pressure targeting) during pregnancy and pregnancy-related pathology are urgently needed to prevent undertreatment, overtreatment, and side effects.

Changes in ophthalmic artery Doppler during acute blood-pressure control in hypertensive pregnant women

OBJECTIVE

To examine the changes in ophthalmic artery Doppler indices and their association with changes in mean arterial blood pressure (MAP) and systolic (SBP) and diastolic (DBP) blood pressure, following acute antihypertensive treatment in women with hypertensive disorders of pregnancy presenting with high blood pressure.

METHODS

This was a prospective cohort study of 31 pregnant women presenting at 30 + 0 to 39 + 6 weeks' gestation for management of their hypertension. Paired maternal blood-pressure and ophthalmic-artery-Doppler measurements were performed prior to and at 30 min and 60 min after starting antihypertensive medication. In patients who did not achieve blood-pressure control (i.e. when blood pressure was < 140/90 mmHg) by 60 min, paired readings were continued up to 120 min. If blood-pressure control was still not achieved at that point, patients were admitted to hospital. Univariate linear regression was performed to determine the association of ophthalmic artery peak systolic velocity (PSV) ratio with SBP, DBP and MAP before treatment and after blood-pressure control. The longitudinal changes in MAP, SBP, DBP and PSV ratio from pretreatment to 30 min and 60 min after commencement of antihypertensives were examined by repeated measure, multilevel, linear mixed-effects analysis.

RESULTS

Antihypertensive treatment was associated with a decrease in SBP, DBP, MAP and PSV ratio. At 60 min following antihypertensive treatment, the decrease in SBP, DBP, MAP and PSV ratio was 12.1 mmHg (95% CI, 9.0-15.1 mmHg; P < 0.0001), 9.1 mmHg (95% CI, 6.5-11.5 mmHg; P < 0.0001), 10.0 mmHg (95% CI, 7.6-12.4 mmHg; P < 0.0001) and 0.07 (95% CI, 0.03-0.11 mmHg; P < 0.001), respectively. From the total cohort, 20 (64.5%) women had achieved blood-pressure control at 60 min and another seven (22.6%) by 120 min from commencement of antihypertensive treatment. Four (12.9%) women did not achieve blood-pressure control during this period and were admitted to hospital. The relationship between PSV ratio and SBP, DBP and MAP was assessed before treatment (n = 31) and at the point of blood-pressure control in women in whom this was achieved by 120 min (n = 27). Prior to treatment, there was a significant association between PSV ratio and MAP (P < 0.0001, R²  = 0.39). This was primarily due to the association of PSV ratio with DBP (P < 0.0001, R²  = 0.39) and less so due to its association with SBP (P = 0.02, R²  = 0.16). At the point of achieving blood-pressure control, there was no significant association between PSV ratio and MAP (P = 0.7), DBP (P = 0.5) or SBP (P = 0.7).

CONCLUSIONS

Acute blood-pressure control in pregnancy is associated with a concomitant reduction in blood pressure and ophthalmic artery PSV ratio. In hypertensive pregnant women, there is a significant association of PSV ratio with MAP, SBP and DBP, which disappears after blood pressure is reduced to < 140/90 mmHg following antihypertensive treatment. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Pharmacomicrobiomics: Exploiting the Drug-Microbiota Interactions in Antihypertensive Treatment

Hypertension is a leading risk factor for cardiovascular diseases and can reduce life expectancy. Owing to the widespread use of antihypertensive drugs, patients with hypertension have improved blood pressure control over the past few decades. However, for a considerable part of the population, these drugs still cannot significantly improve their symptoms. In order to explore the reasons behind, pharmacomicrobiomics provide unique insights into the drug treatment of hypertension by investigating the effect of bidirectional interaction between gut microbiota and antihypertensive drugs. This review discusses the relationship between antihypertensive drugs and the gut microbiome, including changes in drug pharmacokinetics and gut microbiota composition. In addition, we highlight how our current knowledge of antihypertensive drug-microbiota interactions to develop gut microbiota-based personalized ways for disease management, including antihypertensive response biomarker, microbial-targeted therapies, probiotics therapy. Ultimately, a better understanding of the impact of pharmacomicrobiomics in the treatment of hypertension will provide important information for guiding rational clinical use and individualized use.

The impact of pregnancy on antihypertensive drug metabolism and pharmacokinetics: current status and future directions

INTRODUCTION

Hypertensive disorders of pregnancy (HDP) are rising in prevalence, and increase risk of adverse maternal and fetal outcomes. Physiologic changes occur during pregnancy that alter drug pharmacokinetics. However, antihypertensive drugs lack pregnancy-specific dosing recommendations due to critical knowledge gaps surrounding the extent of gestational changes in antihypertensive drug pharmacokinetics and underlying mechanisms.

AREAS COVERED

This review (1) summarizes currently recommended medications and dosing strategies for non-emergent HDP treatment, (2) reviews and synthesizes existing literature identified via a comprehensive Pubmed search evaluating gestational changes in the maternal pharmacokinetics of commonly prescribed HDP drugs (notably labetalol and nifedipine), and (3) offers insight into the metabolism and clearance mechanisms underlying altered HDP drug pharmacokinetics during pregnancy. Remaining knowledge gaps and future research directions are summarized.

EXPERT OPINION

A series of small pharmacokinetic studies illustrate higher oral clearance of labetalol and nifedipine during pregnancy. Pharmacokinetic modeling and preclinical studies suggest these effects are likely due to pregnancy-associated increases in hepatic UGT1A1- and CYP3A4-mediated first-pass metabolism and lower bioavailability. Accordingly, higher and/or more frequent doses may be needed to lower blood pressure during pregnancy. Future research is needed to address various evidence gaps and inform the development of more precise antihypertensive drug dosing strategies.

Simultaneous determination of five alkaloids from Rauvolfia vomitoria in rat plasma by LC-MS/MS: Application to a comparative pharmacokinetic study in normal and type 2 diabetic rats

Rauvolfia vomitoria is widely distributed in the tropical regions of Africa and Asia, and has been used in traditional folk medicine in China. Indole alkaloids were found to be major bioactive components, while the effects of diabetes mellitus on the pharmacokinetic parameters of the components have not been reflected in vivo. In this study, an efficient and sensitive liquid chromatography-tandem mass spectrometry method was developed and validated for the simultaneous determination of five ingredients of R. vomitoria in rats. Detection was implemented in multiple-reaction-monitoring mode with an electrospray positive-ionization source. Validation parameters were all in accordance with the current criterion. The established method was effectively employed to compare the pharmacokinetic behaviors of five alkaloids (reserpine, yohimbine, ajmaline, ajmalicine, and serpentine) between normal and type 2 diabetic rats. The single-dose pharmacokinetic parameters of the five alkaloids were determined in normal and diabetic rats after oral administration of 100 and 200 mg/kg body weight. The results indicated that diabetes mellitus significantly altered the pharmacokinetic characteristics of yohimbine, ajmaline, and ajmalicine after oral administration in rats. This is an attempt to provide some evidence for clinicians that may serve as a guide for the use of antidiabetic medicine in clinical practice.

Effects of Apatinib on the Pharmacokinetics of Nifedipine and Warfarin in Patients with Advanced Solid Tumors

Background and Purpose

Apatinib is a small-molecule tyrosine kinase inhibitor for the treatment of recurrent or progressive advanced-stage gastric adenocarcinoma or gastroesophageal junction cancer. The in vitro inhibition studies suggested that apatinib exerted potent inhibition on CYP3A4 and CYP2C9. To evaluate the potential of apatinib as a perpetrator in CYP450-based drug–drug interactions in vivo, nifedipine and warfarin were, respectively, selected in the present study as the probe substrates of CYP3A4 and CYP2C9 for clinical drug–drug interaction studies. Since hypertension and thrombus are common adverse effects of vascular targeting anticancer agents, nifedipine and warfarin are usually coadministered with apatinib in clinical practice.

Methods

A single-center, open-label, single-arm, and self-controlled trial was conducted in patients with advanced solid tumors. The patients received a single dose of 30 mg nifedipine on Day 1/14 and a single dose of 3 mg warfarin on Day 3/16. On Day 9–21, the subjects received a daily dose of 750 mg apatinib, respectively. The pharmacokinetics of nifedipine and warfarin in the absence or presence of apatinib was, respectively, investigated.

Results

Compared with the single oral administration, coadministration with apatinib contributed to the significant increases of AUC_0–48h and C_max of nifedipine by 83% (90% confidence interval [CI] 1.46–2.31) and 64% (90% CI 1.34–2.01), respectively. Similarly, coadministration with apatinib contributed to the significant increases of AUC_0-t and C_max of S-warfarin by 92% (90% CI 1.68–2.18) and 24% (90% CI 1.10–1.39), respectively.

Conclusion

Concomitant apatinib administration resulted in significant increases in systemic exposure to nifedipine and S-warfarin. Owing to the risk of pharmacokinetic drug–drug interactions based on CYP3A4/CYP2C9 inhibition by apatinib, caution is advised in the concurrent use of apatinib with either CYP2C9 or CYP3A4 substrates.

Imbalance of Drug Transporter-CYP450s Interplay by Diabetes and Its Clinical Significance

The pharmacokinetics of a drug is dependent upon the coordinate work of influx transporters, enzymes and efflux transporters (i.e., transporter-enzyme interplay). The transporter-enzyme interplay may occur in liver, kidney and intestine. The influx transporters involving drug transport are organic anion transporting polypeptides (OATPs), peptide transporters (PepTs), organic anion transporters (OATs), monocarboxylate transporters (MCTs) and organic cation transporters (OCTs). The efflux transporters are P-glycoprotein (P-gp), multidrug/toxin extrusions (MATEs), multidrug resistance-associated proteins (MRPs) and breast cancer resistance protein (BCRP). The enzymes related to drug metabolism are mainly cytochrome P450 enzymes (CYP450s) and UDP-glucuronosyltransferases (UGTs). Accumulating evidence has demonstrated that diabetes alters the expression and functions of CYP450s and transporters in a different manner, disordering the transporter-enzyme interplay, in turn affecting the pharmacokinetics of some drugs. We aimed to focus on (1) the imbalance of transporter-CYP450 interplay in the liver, intestine and kidney due to altered expressions of influx transporters (OATPs, OCTs, OATs, PepTs and MCT6), efflux transporters (P-gp, BCRP and MRP2) and CYP450s (CYP3As, CYP1A2, CYP2E1 and CYP2Cs) under diabetic status; (2) the net contributions of these alterations in the expression and functions of transporters and CYP450s to drug disposition, therapeutic efficacy and drug toxicity; (3) application of a physiologically-based pharmacokinetic model in transporter-enzyme interplay.

Recent Avenues in Novel Patient-Friendly Techniques for the Treatment of Diabetes

Background:

Diabetes is one of the most common chronic metabolic disorders which affect the quality of human life worldwide. As per the WHO report, between 1980 to 2014, the number of diabetes patients increases from 108 million to 422 million, with a global prevalence rate of 8.5% per year. Diabetes is the prime reason behind various other diseases like kidney failure, stroke, heart disorders, glaucoma, etc. It is recognized as the seventh leading cause of death throughout the world. The available therapies are painful (insulin injections) and inconvenient due to higher dosing frequency. Thus, to find out a promising and convenient treatment, extensive investigations are carried out globally by combining novel carrier system (like microparticle, microneedle, nanocarrier, microbeads etc.) and delivery devices (insulin pump, stimuli-responsive device, inhalation system, bioadhesive patch, insulin pen etc.) for more precise diagnosis and painless or less invasive treatment of disease.

Objective:

The review article is made with an objective to compile information about various upcoming and existing modern technologies developed to provide greater patient compliance and reduce the undesirable side effect of the drug. These devices evade the necessity of daily insulin injection and offer a rapid onset of action, which sustained for a prolonged duration of time to achieve a better therapeutic effect.

Conclusion:

Despite numerous advantages, various commercialized approaches, like Afrezza (inhalation insulin) have been a failure in recent years. Such results call for more potential work to develop a promising system. The novel approaches range from the delivery of non-insulin blood glucose lowering agents to insulin-based therapy with minimal invasion are highly desirable.

ABCG2 c.421C>A polymorphism alters nifedipine transport to breast milk in hypertensive breastfeeding women

Nifedipine, a known substrate to breast cancer resistance protein (ABCG2/BCRP), is used for the treatment of hypertension during breastfeeding. This study aimed to evaluate the effect of ABCG2 c.421C>A on nifedipine transfer to breast milk (BM) in hypertensive women. Nineteen hypertensive breastfeeding women treated with 20 mg nifedipine every 12 hours were investigated. Blood and BM samples were collected simultaneously 15-30 days after delivery and at least 15 days after drug treatment. Patients genotyped as ABCG2 c.421CC showed nifedipine plasma and BM concentrations ranging from 8.32-178.1 ng/mL and 4.8-58.5 ng/mL, respectively. ABCG2 c.421C>A showed a trend towards significance (p = 0.0793) on nifedipine in BM, with concentrations approximately 3 times higher in the heterozygous 421 CA (29 ng/mL) in comparison to 421 CC (10.5 ng/mL). Nifedipine BM/plasma ratio was significantly lower in 421CC when compared to 421CA (p = 0.01). In conclusion, ABCG2 c.421C>A polymorphism is associated with higher transfer of nifedipine to BM.

Plateau hypoxia attenuates the metabolic activity of intestinal flora to enhance the bioavailability of nifedipine

Nifedipine is completely absorbed by the gastrointestinal tract and its pharmacokinetics and metabolism may be influenced by microorganisms. If gut microbes are involved in the metabolism of nifedipine, plateau hypoxia may regulate the bioavailability and the therapeutic effect of nifedipine by altering the metabolic activity of the gut microbiota. We herein demonstrated for the first time that gut flora is involved in the metabolism of nifedipine by in vitro experiments. In addition, based on the results of 16S rRNA analysis of feces in rats after acute plateau, we first confirmed that the plateau environment could cause changes in the number and composition of intestinal microbes. More importantly, these changes in flora could lead to a slower metabolic activity of nifedipine in the body after an acute plateau, resulting in increased bioavailability and therapeutic efficacy of nifedipine. Our research will provide basis and new ideas for changes in the fecal flora of human acutely entering the plateau, and contribute to rational drug use of nifedipine.

Effect of type 2 diabetes mellitus on the pharmacokinetics and transplacental transfer of nifedipine in hypertensive pregnant women

AIMS

Diabetes mellitus can inhibit cytochrome P450 3A4, an enzyme responsible for the metabolism of nifedipine, used for the treatment of hypertension in pregnant women. We aimed to assess the effect of type 2 diabetes mellitus (T2DM) on the pharmacokinetics, placental transfer and distribution of nifedipine in amniotic fluid in hypertensive pregnant women.

METHODS

The study was conducted in 12 hypertensive pregnant women [control group (CG)] and 10 hypertensive pregnant women with T2DM taking slow-release nifedipine (20 mg, 12/12 h). On the 34th week of gestation, serial blood samples were collected (0-12 h) after administration of the medication. At delivery, samples of maternal and fetal blood and amniotic fluid were collected for determination of nifedipine distribution in these compartments.

RESULTS

The median pharmacokinetic parameters of CG were: peak plasma concentration (C_max ) 26.41 ng ml^-1 , time to reach C_max (t_max ) 1.79 h, area under the plasma concentration vs. time curve from 0-12 h (AUC_0-12 ) 235.99 ng.h ml^-1 , half-life (t½) 4.34 h, volume of distribution divided by bioavailability (Vd/F) 560.96 l, and Cl_T /F 84.77 l h^-1 . The parameters for T2DM group were: C_max 23.52 ng ml^-1 , t_max 1.48 h, AUC_0-12 202.23 ng.h ml^-1 , t½ 5.00 h, Vd/F 609.40 l, and apparent total clearance (Cl_T /F) 98.94 l h^-1 . The ratios of plasma concentrations of nifedipine in the umbilical vein, intervillous space and amniotic fluid to those in the maternal vein for CG and T2DM were 0.53 and 0.44, 0.78 and 0.87, respectively, with an amniotic fluid/maternal plasma ratio of 0.05 for both groups. The ratios of plasma concentrations in the umbilical artery to those in the umbilical vein were 0.82 for CG and 0.88 for T2DM.

CONCLUSIONS

There was no influence of T2DM on the pharmacokinetics or placental transfer of nifedipine in hypertensive women with controlled diabetes.