Evaluation of the in vitro/in vivo drug interaction potential of BST204, a purified dry extract of ginseng, and its four bioactive ginsenosides through cytochrome P450 inhibition/induction and UDP-glucuronosyltransferase inhibition

Pharmacokinetics and pharmacodynamics of Rh2 and aPPD ginsenosides in prostate cancer: a drug interaction perspective

Ginsenoside Rh2 and its aglycon (aPPD) are one of the major metabolites from Panax ginseng. Preclinical studies suggest that Rh2 and aPPD have antitumor effects in prostate cancer (PCa). Our aims in this review are (1) to describe the pharmacokinetic (PK) properties of Rh2 and aPPD ginsenosides; 2) to provide an overview of the preclinical findings on the use of Rh2 and aPPD in the treatment of PCa; and (3) to highlight the mechanisms of its PK and pharmacodynamic (PD) drug interactions. Increasing evidence points to the potential efficacy of Rh2 or aPPD for PCa treatment. Based on the laboratory studies, Rh2 or aPPD combinations revealed an additive or synergistic interaction or enhanced sensitivity of anticancer drugs toward PCa. This review reveals that enhanced anticancer activities were demonstrated in preclinical studies through interactions of Rh2 and/or aPPD with the proteins related to PK (e.g., cytochrome P450 enzymes, transporters) or PD of the other anticancer drugs or PCa signaling pathways. In conclusion, combining Rh2 or aPPD with anti-prostate cancer drugs leads to PK or PD interactions which could facilitate either therapeutically beneficial or toxic effects.

Benzisothiazolinone: Pharmacokinetics, Tissue Distribution, and Mass Balance Studies in Rats

Humans are continuously exposed to benzisothiazolinone (BIT), which is used as a preservative, through multiple routes. BIT is known to be a sensitizer; in particular, dermal contact or aerosol inhalation could affect the local toxicity. In this study, we evaluated the pharmacokinetic properties of BIT in rats following various routes of administration. BIT levels were determined in rat plasma and tissues after oral inhalation and dermal application. Although the digestive system rapidly and completely absorbed orally administered BIT, it underwent severe first-pass effects that prevented high exposure. In an oral dose escalation study (5-50 mg/kg), nonlinear pharmacokinetic properties showed that C_max and the area under the curve (AUC) increased more than dose proportionality. In the inhalation study, the lungs of rats exposed to BIT aerosols had higher BIT concentrations than the plasma. Additionally, the pharmacokinetic profile of BIT after the dermal application was different; continuous skin absorption without the first-pass effect led to a 2.13-fold increase in bioavailability compared with oral exposure to BIT. The [¹⁴C]-BIT mass balance study revealed that BIT was extensively metabolized and excreted in the urine. These results can be used in risk assessments to investigate the relationship between BIT exposure and hazardous potential.

The mechanism of Renshen-Fuzi herb pair for treating heart failure-Integrating a cardiovascular pharmacological assessment with serum metabolomics

Background: Renshen-Fuzi herb pair (RS-FZ) is often used in the clinical treatment of heart failure (HF) and has a remarkable therapeutic effect. However, the mechanism of RS-FZ for treating HF remains unclear. In our study, we explored the mechanism of RS-FZ for treating HF. Methods: Evaluation of RS-FZ efficacy by cardiovascular pharmacology. Moreover, Global metabolomics profiling of the serum was detected by UPLC-QTOF/MS. Multivariate statistics analyzed the specific serum metabolites and corresponding metabolic pathways. Combining serum metabolomics with network pharmacology, animal experiments screened and validated the critical targets of RS-FZ intervention in HF. Results: RS-FZ significantly ameliorated myocardial fibrosis, enhanced cardiac function, and reduced the serum HF marker (brain natriuretic peptide) level in rats with HF. Through topological analysis of the "Metabolite-Target-Component" interaction network, we found that 79 compounds of RS-FZ directly regulated the downstream specific serum metabolites by acting on four critical target proteins (CYP2D6, EPHX2, MAOB, and ENPP2). The immunohistochemistry results showed that RS-FZ observably improved the expression of CYP2D6 and ENPP2 proteins while decreasing the expression of EPHX2 and MAOB proteins dramatically. Conclusion: The integrated cardiovascular pharmacological assessment with serum metabolomics revealed that RS-FZ plays a crucial role in the treatment of HF by intervening in CYP2D6, EPHX2, MAOB, and ENPP2 target proteins. It provides a theoretical basis for RS-FZ for treating HF.

Bulbine natalensis (currently Bulbine latifolia) and select bulbine knipholones modulate the activity of AhR, CYP1A2, CYP2B6, and P-gp

Bulbine natalensis, an emerging medicinal herb on the global market with androgenic properties, is often formulated in dietary supplements that promote perceived sexual enhancement. However, to date, comprehensive safety studies of B. natalensis are lacking, particularly those related to its herb-drug interaction potential. The purpose of this study was to assess the inductive and inhibitory effects of extracts and pure compounds of B. natalensis on human cytochrome P-450 isozymes in vitro. Our findings demonstrated that both water and methanolic extracts of B. natalensis as well as knipholone, bulbine-knipholone, and 6'-O-methylknipholone dose-dependently increased mRNA expression encoded by CYP2B6, CYP1A2, and ABCB1 genes. Functional analyses showed that water (60 to 2.20 µg/mL) and methanolic (30 to 3.75 µg/mL) extracts and knipholones (10 to 0.33 µM) increased CYP2B6 and CYP1A2 activity in a dose-dependent manner. Additionally, water extract (60 µg/mL), methanolic extract (30 µg/mL), and knipholone (10 µM) caused activation of the aryl hydrocarbon receptor up to 11.1 ± 0.7, 8.9 ± 0.6, and 7.1 ± 2.0-fold, respectively. Furthermore, inhibition studies revealed that methanolic extract attenuated the activity of metabolically active CYP1A2 (IC₅₀, 22.6 ± 0.4 µg/mL) and CYP2B6 (IC₅₀, 34.2 ± 6.6 µg/mL) proteins, whereas water extracts had no inhibitory effect on either isoform. These findings suggest that chronic consumption of B. natalensis may affect normal homeostasis of select CYPs with subsequent risks for HDIs when concomitantly ingested with conventional medications that are substrates of CYP2B6 and CYP1A2. However, more in-depth translational studies are required to validate our current findings and their clinical relevance.

Dietary supplements, cytochrome metabolism, and pharmacogenetic considerations

BACKGROUND

Dietary supplement use has continued to rise. In addition to supplement-drug interactions, it is prudent to consider how dietary supplements may interact with a patient's specific pharmacogenetics. Variations in genes associated with CYP 450 enzymes have evidence of impacting drug metabolism and adverse effects.

AIMS

This research was performed to evaluate CYP P450 enzyme activity of the top 15 dietary supplements used in the USA in order to initiate pharmacogenetic considerations specific to commonly used dietary supplements.

METHODS

The most common dietary supplements used in the USA were obtained from the National Health and Nutrition Examination Survey (NHANES). Primary literature detailing supplement CYP P450 activity was compiled from PubMed using MeSH search terms: supplement name(s), cytochrome P450 enzymes, metabolism, and pharmacokinetics. Additional resources utilized for documented CYP enzyme genotypes were the pharmacogenetic databases from Clinical Pharmacogenetics Implementation Consortium and The Pharmacogenomic Variation Consortium.

RESULTS

Of the 15 most common dietary supplements used in the USA, 53% (cranberry, echinacea, garlic, ginkgo biloba, ginseng, melatonin, milk thistle, and valerian) exhibit CYP P450 metabolism, with some having possible induction activity as well. Melatonin and garlic are substrates of CYP1A2 and CYP2C19, respectively. Additionally, there is evidence of echinacea having possible CYP3A4 induction activity.

CONCLUSION

CYP P450 activity is an important consideration for any patient but becomes increasingly critical if patients have certain CYP P450 phenotypes that impact metabolism. These popular supplements have the potential for changes in supplement exposure, and adverse effects based on pharmacogenetic profiles. Furthermore, these sites of metabolism are shared with many medications, setting the stage for possibly more profound interactions between medications and supplements. This paper highlights the mechanisms in which dietary supplements may constitute a risk for patients with certain CYP P450 phenotypes. Further research is needed in the area of dietary supplements and their pharmacogenomic implications.

In vitro modulatory effects of ginsenoside compound K, 20(S)-protopanaxadiol and 20(S)-protopanaxatriol on uridine 5'-diphospho-glucuronosyltransferase activity and expression

We explored the inhibitory effect of ginsenoside compound K (CK), 20(S)-protopanaxadiol (PPD), and 20(S)-protopanaxatriol (PPT) on six uridine 5'-diphospho-glucuronosyltransferase (UGT) enzyme (UGT1A1, 1A3, 1A4, 1A6, 1A9, and 2B7) activities in human liver microsomes (HLMs) and 10 UGT enzyme (UGT1A1, 1A3, 1A4, 1A6, 1A9, 2B4, 2B7, 2B10, 2B15, and 2B17) activities in recombinant UGT isoforms.PPD was a potent inhibitor of UGT1A3 activity with half-maximal inhibitory concentration values of 5.62 and 3.38 μM in HLMs and recombinant UGT1A3, respectively. UGT1A3 inhibition by CK and PPD was competitive with inhibitory constant (K_i) values of 17.4 and 1.21 μM, respectively, and inhibition by PPT was non-competitive with a K_i value of 8.07 μM in HLMs. PPD exhibited more than 3.4-fold selectivity for UGT1A3 inhibition compared with other UGT isoforms inhibition, while CK and PPT showed more than 2.16- and 2.21-fold selectivity, respectively.PPD did not significantly increase the mRNA expression of UGT1A1, 1A3, 1A4, 1A9, and 2B7 in hepatocytes.Given the low plasma concentrations of PPD in healthy human subjects and the absence of induction potential on UGT isoforms, we conclude that PPD cause no pharmacokinetic interactions with other co-administered drugs metabolised by UGT1A3.

Potential Cytochrome P450-mediated pharmacokinetic interactions between herbs, food, and dietary supplements and cancer treatments

Herbs, food and dietary supplements (HFDS), can interact significantly with anticancer drug treatments via cytochrome p450 isoforms (CYP) CYP3A4, CYP2D6, CYP1A2, and CYP2C8. The objective of this review was to assess the influence of HFDS compounds on these cytochromes. Interactions with CYP activities were searched for 189 herbs and food products, 72 dietary supplements in Web of Knowledge® databases. Analyses were made from 140 of 3,125 clinical trials and 236 of 3,374 in vitro, animal model studies or case reports. 18 trials were found to report direct interactions between 9 HFDS with 8 anticancer drugs. 21 HFDS were found to interact with CYP3A4, a major metabolic pathway for many anticancer drugs. All 261 HFDS were classified for their interaction with the main cytochromes P450 involved in the metabolism of anticancer drugs. We provided an easy-to-use colour-coded table to easily match potential interactions between 261 HFDS and 117 anticancer drugs.

A systematic review of possible interactions for herbal medicines and dietary supplements used concomitantly with disease-modifying or symptom-alleviating multiple sclerosis drugs

Multiple Sclerosis (MS) is a demyelinating disease affecting the central nervous system, with no curative medicine available. The use of herbal drugs and dietary supplements is increasing among people with MS (PwMS), raising a need for knowledge about potential interactions between conventional MS medicine and herbal drugs/dietary supplements. This systematic review provides information about the safety of simultaneous use of conventional MS-drugs and herbal drugs frequently used by PwMS. The study included 14 selected disease-modifying treatments and drugs frequently used for symptom-alleviation. A total of 129 published papers found via PubMed and Web of Science were reviewed according to defined inclusion- and exclusion criteria. Findings suggested that daily recommended doses of Panax ginseng and Ginkgo biloba should not be exceeded, and herbal preparations differing from standardized products should be avoided, especially when combined with anticoagulants or substrates of certain cytochrome P450 isoforms. Further studies are required regarding ginseng's ability to increase aspirin bioavailability. Combinations between chronic cannabis use and selective serotonin reuptake inhibitors or non-steroidal antiinflammatory drugs should be carefully monitored, whereas no significant evidence for drug-interactions between conventional MS-drugs and ginger, cranberry, vitamin D, fatty acids, turmeric, probiotics or glucosamine was found.

Evaluation of the Efficacy and Safety of the Herbal Formula PM014 in a Cisplatin- and Paclitaxel-Treated Tumor-Bearing Mouse Model

PM014 (HL301) is a standardized herbal mixture derived from a traditional Korean medicine, Chung-Sang-Bo-Ha-Tang. Previously, we reported that PM014 treatment significantly suppressed pulmonary fibrosis, one of the frequent adverse effects of anticancer therapy in lung cancer. Before the clinical application of PM014 in anticancer therapy, the safety and efficacy of PM014 in combination with conventional anticancer drugs should be addressed to determine whether PM014 can be used in lung cancer. Lewis lung cancer–bearing mice were injected with 10 mg/kg of cisplatin or paclitaxel on day 5. Starting on day 7, the mice were administered 200 mg/kg PM014 every 2 days. On day 15, all mice were assessed by biochemical and histological analyses. PM014 did not block the antitumor activity of cisplatin and paclitaxel. Coadministration of PM014 and antitumor agents did not elevate the aspartate transaminase/alanine transaminase ratio or the blood urea nitrogen/creatinine ratio. Histopathological analysis also showed that PM014 did not induce hepatic or renal injury. Moreover, PM014 had no apparent inhibitory effects on drug metabolizing enzymes, indicating that PM014 did not alter the pharmacokinetics of chemotherapeutic drugs. Overall, these data show the safety and compatibility of combination therapy of PM014 and chemotherapies for the treatment of lung cancer.

Lack of Correlation between In Vitro and In Vivo Studies on the Inhibitory Effects of (‒)-Sophoranone on CYP2C9 is Attributable to Low Oral Absorption and Extensive Plasma Protein Binding of (‒)-Sophoranone

(‒)-Sophoranone (SPN) is a bioactive component of Sophora tonkinensis with various pharmacological activities. This study aims to evaluate its in vitro and in vivo inhibitory potential against the nine major CYP enzymes. Of the nine tested CYPs, it exerted the strongest inhibitory effect on CYP2C9-mediated tolbutamide 4-hydroxylation with the lowest IC₅₀ (K_i) value of 0.966 ± 0.149 μM (0.503 ± 0.0383 μM), in a competitive manner. Additionally, it strongly inhibited other CYP2C9-catalyzed diclofenac 4′-hydroxylation and losartan oxidation activities. Upon 30 min pre-incubation of human liver microsomes with SPN in the presence of NADPH, no obvious shift in IC₅₀ was observed, suggesting that SPN is not a time-dependent inactivator of the nine CYPs. However, oral co-administration of SPN had no significant effect on the pharmacokinetics of diclofenac and 4′-hydroxydiclofenac in rats. Overall, SPN is a potent inhibitor of CYP2C9 in vitro but not in vivo. The very low permeability of SPN in Caco-2 cells (P_app value of 0.115 × 10⁻⁶ cm/s), which suggests poor absorption in vivo, and its high degree of plasma protein binding (>99.9%) may lead to the lack of in vitro–in vivo correlation. These findings will be helpful for the safe and effective clinical use of SPN.

Herbal Interaction With Chemotherapeutic Drugs-A Focus on Clinically Significant Findings

One of the most consequential risks associated with the concomitant use of herbal products and chemotherapeutic agents is herb-drug interactions. The risk is higher in patients with chronic conditions taking multiple medications. Herb-drug interaction is particularly undesirable in cancer management because of the precipitous dose-effect relationship and toxicity of chemotherapeutic agents. The most common mechanism of herb-drug interaction is the herbal-mediated inhibition and/or induction of drug-metabolizing enzymes (DME) and/or transport proteins leading to the alteration in the pharmacokinetic disposition of the victim drug. Most mechanistic research has focused on laboratory-based studies, determining the effects of herbal products on DMEs and extrapolating findings to predict clinical relevance; however, not all DME/transporter protein inhibition/induction results in clinical herb-drug interaction. This study reviews relevant literature and identified six herbal products namely echinacea, garlic, ginseng, grapefruit juice, milk thistle, and St John's wort, which have shown interactions with chemotherapeutic agents in humans. This focus on clinically significant herb-drug interaction, should be of interest to the public including practitioners, researchers, and consumers of cancer chemotherapy.

Recent progress and challenges in screening and characterization of UGT1A1 inhibitors

Uridine-diphosphate glucuronosyltransferase 1A1 (UGT1A1) is an important conjugative enzyme in mammals that is responsible for the conjugation and detoxification of both endogenous and xenobiotic compounds. Strong inhibition of UGT1A1 may trigger adverse drug/herb-drug interactions, or result in metabolic disorders of endobiotic metabolism. Therefore, both the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) have recommended assaying the inhibitory potential of drugs under development on the human UGT1A1 prior to approval. This review focuses on the significance, progress and challenges in discovery and characterization of UGT1A1 inhibitors. Recent advances in the development of UGT1A1 probes and their application for screening UGT1A1 inhibitors are summarized and discussed in this review for the first time. Furthermore, a long list of UGT1A1 inhibitors, including information on their inhibition potency, inhibition mode, and affinity, has been prepared and analyzed. Challenges and future directions in this field are highlighted in the final section. The information and knowledge that are presented in this review provide guidance for rational use of drugs/herbs in order to avoid the occurrence of adverse effects via UGT1A1 inhibition, as well as presenting methods for rapid screening and characterization of UGT1A1 inhibitors and for facilitating investigations on UGT1A1-ligand interactions.

Potential Intervention Targets in Utero and Early Life for Prevention of Hormone Related Cancers

Hormone-related cancers have long been thought to be sensitive to exposures during key periods of sexual development, as shown by the vulnerability to such cancers of women exposed to diethylstilbestrol in utero. In addition to evidence from human studies, animal studies using new techniques, such as gene knockout models, suggest that an increasing number of cancers may be hormonally related, including liver, lung, and bladder cancer. Greater understanding of sexual development has also revealed the "mini-puberty" of early infancy as a key period when some sex hormones reach levels similar to those at puberty. Factors driving sex hormones in utero and early infancy have not been systematically identified as potential targets of intervention for cancer prevention. On the basis of sex hormone pathways, we identify common potentially modifiable drivers of sex hormones, including but not limited to factors such as obesity, alcohol, and possibly nitric oxide. We review the evidence for effects of modifiable drivers of sex hormones during the prenatal period and early infancy, including measured hormones as well as proxies, such as the second-to-fourth digit length ratio. We summarize the gaps in the evidence needed to identify new potential targets of early life intervention for lifelong cancer prevention.

Role of Cytochrome P450 2C8 in Drug Metabolism and Interactions

During the last 10-15 years, cytochrome P450 (CYP) 2C8 has emerged as an important drug-metabolizing enzyme. CYP2C8 is highly expressed in human liver and is known to metabolize more than 100 drugs. CYP2C8 substrate drugs include amodiaquine, cerivastatin, dasabuvir, enzalutamide, imatinib, loperamide, montelukast, paclitaxel, pioglitazone, repaglinide, and rosiglitazone, and the number is increasing. Similarly, many drugs have been identified as CYP2C8 inhibitors or inducers. In vivo, already a small dose of gemfibrozil, i.e., 10% of its therapeutic dose, is a strong, irreversible inhibitor of CYP2C8. Interestingly, recent findings indicate that the acyl-β-glucuronides of gemfibrozil and clopidogrel cause metabolism-dependent inactivation of CYP2C8, leading to a strong potential for drug interactions. Also several other glucuronide metabolites interact with CYP2C8 as substrates or inhibitors, suggesting that an interplay between CYP2C8 and glucuronides is common. Lack of fully selective and safe probe substrates, inhibitors, and inducers challenges execution and interpretation of drug-drug interaction studies in humans. Apart from drug-drug interactions, some CYP2C8 genetic variants are associated with altered CYP2C8 activity and exhibit significant interethnic frequency differences. Herein, we review the current knowledge on substrates, inhibitors, inducers, and pharmacogenetics of CYP2C8, as well as its role in clinically relevant drug interactions. In addition, implications for selection of CYP2C8 marker and perpetrator drugs to investigate CYP2C8-mediated drug metabolism and interactions in preclinical and clinical studies are discussed.

The different metabolism of morusin in various species and its potent inhibition against UDP-glucuronosyltransferase (UGT) and cytochrome p450 (CYP450) enzymes

1. The aim of this study was to investigate the inhibitory effect of morusin on Glucuronosyltransferase (UGT) isoforms and cytochrome P450 enzymes (CYP450s). We also investigated the metabolism of morusin in human, rat, dog, monkey, and minipig liver microsomes. 2. 100 μM of morusin exhibited strong inhibition on all UGTs and CYP450s. The half inhibition concentration (IC50) values for CYP3A4, CYP1A2, CYP2C9, CYP2E1, UGT1A6, UGT1A7, and UGT1A8 were 2.13, 1.27, 3.18, 9.28, 4.23, 0.98, and 3.00 μM, and the inhibition kinetic parameters (Ki) were 1.34, 1.16, 2.98, 6.23, 4.09, 0.62, and 2.11 μM, respectively. 3. Metabolism of morusin exhibited significant species differences. The quantities of M1 from minipig, monkey, dog, and rat were 7.8, 11.9, 2.0, and 6.3-fold of human levels. The Km values in HLMs, RLMs, MLMs, DLMs, and PLMs were 7.84, 22.77, 14.32, 9.13, and 22.83 μM, and Vmax for these species were 0.09, 1.23, 1.43, 0.15, and 0.75 nmol/min/mg, respectively. CLint (intrinsic clearance) values (Vmax/Km) for morusin obeyed the following order: monkey > rat > minipig > dog > human. CLH (hepatic clearance) values for humans, dogs, and rats were calculated to be 8.28, 17.38, and 35.12 mL/min/kg body weight, respectively. 4. This study provided vital information to understand the inhibitory potential and metabolic behavior of morusin among various species.