Ingredients in fruit juices interact with dasatinib through inhibition of BCRP: a new mechanism of beverage-drug interaction

Newly synthesized chitosan nanoparticles loaded with caffeine/moringa leaf extracts Halt Her2, BRCA1, and BRCA2 expressions

Breast cancer is among the highest morbidity and mortality rates in women around the world. In the present investigation we aimed to synthesis novel nanosystem combining two naturally important anticancer agents with different mechanism of action namely Moringa oleifera and caffeine. Firstly, chemical analysis of Moringa oleifera extract and caffeine was done by gas chromatography-mass spectroscopy (GC-MS) in order to assess the main chemical compounds present and correlate between them and the possible anticancer effect. The novel nanosystem was characterized through dynamic light scattering techniques which revealed the stability and homogeneity of the prepared M. oleifera leaves extract/Caffeine loaded chitosan nanoparticles, while FTIR and transmission electron microscope (TEM) proved the shape and the successful incorporation of M. oleifera leaves extract/Caffeine onto the nanochitosan carrier. Our initial step was to assess the anticancer effect in vitro in cancer cell line MCF-7 which proved the significant enhanced effect of M. oleifera leaves extract/Caffeine nanosystem compared to M. oleifera leaves extract or caffeine loaded nanoparticles. Further studies were conducted in vivo namely tumor biomarkers, tumor volume, bioluminescence imaging, molecular and histopathological investigations. The present study proved the potent anticancer effect of the synthesized M. oleifera leaves extract/Caffeine loaded chitosan nanoparticles. Mo/Caf/CsNPs exhibited a large number of apoptotic cells within the tumor mass while the adipose tissue regeneration was higher compared to the positive control. The prepared nanoparticles downregulated the expression of Her2, BRCA1 and BRCA2 while mTOR expression was upregulated. The aforementioned data demonstrated the successful synergistic impact of Moringa and caffeine in decreasing the carcinoma grade.

Pharmacokinetics of Dasatinib in Rats: a Potential Food-Drug Interaction with Naringenin

BACKGROUND AND OBJECTIVES

The novel tyrosine kinase inhibitor (TKI) dasatinib, a multitarget inhibitor of Bcr-Abl and Src family kinases, has been licensed for the treatment of Ph+ acute lymphoblastic leukemia and chronic myeloid leukemia. Many citrus-based foods include the flavonoid naringenin, which is commonly available. Dasatinib is a Cyp3a4, P-gp, and Bcrp1 substrate, which makes it sensitive to potential food-drug interactions. The concurrent use of naringenin may change the pharmacokinetics of dasatinib, which could result in adverse effects and toxicity. The present investigation examined the impact of naringenin on the pharmacokinetics interactions of DAS and proposes a possible interaction mechanism in Wistar rats.

METHODS

Rats were provided with a single oral dose of dasatinib (25 mg/kg) with or without naringenin pretreatment (150 mg/kg p.o. daily for 7 days, n = 6 in each group). Dasatinib was quantified in plasma by UHPLC MS/MS assay. Noncompartmental analysis was used to compute the pharmacokinetic parameters, and immunoblot was used to assess the protein expression in the hepatic and intestinal tissues.

RESULTS

Following 7 days of naringenin pretreatment, the plasma mean concentration of dasatinib was enhanced compared with without pretreatment. In rats that were pretreated with naringenin, the pharmacokinetics of the orally administered dasatinib (25 mg/kg) was shown to be significantly different from that of dasatinib given without pretreatment (p < 0.05). There was a significant enhancement in pharmacokinetic parameters elimination half-life (T1/2), time to maximum concentration ( Tmax), maximum concentration )Cmax), area under the concentration-time curve (AUC0-t), area under the moment curve (AUMC0-∞), and mean residence time (MRT) by 28.41%, 50%, 103.54%, 72.64%, 115.08%, and 15.19%, respectively (p < 0.05) and suppression in elimination rate constant (Kel), volume of distribution (Vd), and clearance (CL) by 21.09%, 31.13%, and 46.25%, respectively, in comparison with dasatinib alone group (p < 0.05). The enhancement in dasatinib bioavailability and systemic exposure resulted from the significant inhibition of Cyp3a2, Mdr1/P-gp, and Bcrp1 expression and suppression of the dasatinib hepatic and intestinal metabolism, which enhanced the rate of dasatinib absorption and decreased its elimination.

CONCLUSION

Concurrent use of naringenin-containing supplements, herbs, or foods with dasatinib may cause serious and potentially life-threatening drug interactions. Further studies are necessary to determine the clinical significance of these findings.

Polymethoxylated flavonoids in citrus fruits: absorption, metabolism, and anticancer mechanisms against breast cancer

Polymethoxylated flavonoids (PMFs) are a subclass of flavonoids found in citrus fruits that have shown multifunctional biological activities and potential anticancer effects against breast cancer. We studied the absorption, metabolism, species source, toxicity, anti-cancer mechanisms, and molecular targets of PMFs to better utilize their anticancer activity against breast cancer. We discuss the absorption and metabolism of PMFs in the body, including the methylation, demethylation, and hydroxylation processes. The anticancer mechanisms of PMFs against breast cancer were also reviewed, including the estrogen activity, cytochrome P-450 enzyme system, and arylhydrocarbon receptor (AhR) inhibition, along with various molecular targets and potential anticancer effects. Although PMFs may be advantageous in the prevention and treatment for breast cancer, there is a lack of clinical evidence and data to support their efficacy. Despite their promise, there is still a long way to go before PMFs can be applied clinically.

Herb-drug interaction: Effect of sinapic acid on the pharmacokinetics of dasatinib in rats

Dasatinib (DAS) is a narrow therapeutic index drug and novel oral multitarget inhibitor of tyrosine kinase and approved for the first-line therapy for chronic myelogenous leukemia (CML) and Philadelphia chromosome (Ph + ) acute lymphoblastic leukemia (ALL). DAS, a known potent substrate of cytochrome (CYP) 3A, P-glycoprotein (Pgp) and breast cancer resistance protein (BCRP) and is subject to auto-induction. The dietary supplementation of sinapic acid (SA) or concomitant use of SA containing herbs/foods may alter the pharmacokinetics as well as pharmacodynamics of DAS, that may probably lead to potential interactions. Protein expression in rat hepatic and intestinal tissues, as well as the in vivo pharmacokinetics of DAS and the roles of CYP3 A2 and drug transporters Pgp-MDR1 and BCPR/ABCG2, suggested a likely interaction mechanism. The single dose of DAS (25 mg/kg) was given orally to rats with or without SA pretreatment (20 mg/kg p.o. per day for 7 days, n = 6). The plasma concentration of DAS was estimated by using Ultra-High-Performance Liquid Chromatography Mass spectrometry (UHPLC-MS/MS). The in vivo pharmacokinetics and protein expression study demonstrate that SA pretreatment has potential to alter the DAS pharmacokinetics. The increase in Cmax, AUC and AUMC proposes increase in bioavailability and rate of absorption via modulation of CYP3 A2, PgP-MDR1 and BCPR/ABCG2 protein expression. Thus, the concomitant use of SA alone or with DAS may cause serious life-threatening drug interactions.

Dasatinib: a potential tyrosine kinase inhibitor to fight against multiple cancer malignancies

Dasatinib is the 2nd generation TKI (Tyrosine Kinase Inhibitor) having the potential to treat numerous forms of leukemic and cancer patients and it is 300 times more potent than imatinib. Cancer is the major cause of death globally and need to enumerate novel strategies to coping with it. Various novel therapeutics introduced into the market for ease in treating various forms of cancer. We reviewed and evaluated all the related aspects of dasatinib, which can enhance the knowledge about dasatinib therapeutics methodology, pharmacodynamic and pharmacokinetics, side effects, advantages, disadvantages, various kinds of interactions and its novel formulations as well.

Effects of Apigenin on Pharmacokinetics of Dasatinib and Probable Interaction Mechanism

Dasatinib (DAS), a narrow-therapeutic index drug, Bcr-Abl, and Src family kinases multitarget inhibitor have been approved for chronic myelogenous leukemia (CML) and Ph-positive acute lymphocytic leukemia (Ph+ ALL). Apigenin (APG) has a long history of human usage in food, herbs, health supplements, and traditional medicine, and it poses low risk of damage. The concomitant use of APG containing herbs/foods and traditional medicine may alter the pharmacokinetics of DAS, that probably lead to possible herb-drug interactions. The pharmacokinetic interaction of APG pretreatment with DAS in rat plasma following single and co-oral dosing was successfully deliberated using the UPLC-MS/MS method. The in vivo pharmacokinetics and protein expression of CYP3A2, Pgp-MDR1, and BCPR/ABCG2 demonstrate that APG pretreatment has potential to drastically changed the DAS pharmacokinetics where escalation in the Cmax, AUC_(0-t), AUMC_{(0-inf_obs)}, T_1/2, Tmax, and MRT and reduction in Kel, Vd, and Cl significantly in rats pretreated with APG 40 mg/kg, thus escalating systemic bioavailability and increasing the rate of absorption via modulation of CYP3A2, Pgp-MDR1, and BCPR/ABCG2 protein expression. Therefore, the concomitant consumption of APG containing food or traditional herb with DAS may cause serious life-threatening drug interactions and more systematic clinical study on herb-drug interactions is required, as well as adequate regulation in herbal safety and efficacy.

Effect of Green Tea Extract and Soy Isoflavones on the Pharmacokinetics of Rosuvastatin in Healthy Volunteers

Background and Aim

Green tea and soy products are extensively consumed in daily life. Research has shown that green tea catechins and soy isoflavones may influence the activity of drug metabolizing enzymes and drug transporters. We examined whether regular consumption of green tea extract or soy isoflavones affected the pharmacokinetics of a single dose of rosuvastatin in healthy subjects and whether any interactions were influenced by the polymorphism in the drug transporter ABCG2.

Study Design

This was an open-label, three-phase randomized crossover study with single doses of rosuvastatin.

Methods

Healthy Chinese male subjects were given a single dose of rosuvastatin 10 mg on 3 occasions: 1. without herbs; 2. with green tea extract; 3. with soy isoflavone extract. The green tea and soy isoflavone extract were given at a dose containing EGCG 800 mg once daily or soy isoflavones−80 mg once daily for 14 days before statin dosing and at the same time as the statin dosing with at least 4-weeks washout period between phases.

Results

Twenty healthy male subjects completed the study and the intake of green tea extract significantly reduced the systemic exposure to rosuvastatin by about 20% reducing AUC_0−24h from [geometric mean (% coefficient of variation)] 108.7 (28.9) h·μg/L to 74.1 (35.3) h·μg/L and C_max from 13.1 (32.2) μg/L to 7.9 (38.3) μg/L (P < 0.001 for both), without affecting the elimination half-life. The ABCG2 421C>A polymorphism had a significant effect on rosuvastatin exposure but no impact on the interaction with green tea. Soy isoflavones had no significant effect on rosuvastatin pharmacokinetics.

Conclusion

This study showed that repeated administration of green tea extract significantly reduced the systemic exposure of rosuvastatin in healthy volunteers. These effects might be predicted to either reduce or increase the lipid-lowering effect of rosuvastatin depending on the mechanism of the effect.

Nobiletin as a chemopreventive natural product against cancer, a comprehensive review

As a leading cause of death, second only to heart disease, cancer has always been one of the burning topics in medical research. When targeting multiple signal pathways in tumorigenesis chemoprevention, using natural or synthetic anti-cancer drugs is a vital strategy to reduce cancer damage. However, toxic effects, multidrug resistance (MDR) as well as cancer stem cells (CSCs) all prominently limited the clinical application of conventional anticancer drugs. With low side effects, strong biological activity, unique mechanism, and wide range of targets, natural products derived from plants are considered significant sources for new drug development. Nobiletin is one of the most attractive compounds, a unique flavonoid primarily isolated from the peel of citrus fruits. Numerous studies in vitro and in vivo have suggested that nobiletin and its derivatives possess the eminent potential to become effective cancer chemoprevention agents through various cellular and molecular levels. This article aims to comprehensively review the anticancer efficacy and specific mechanisms of nobiletin, enhancing our understanding of its chemoprevention properties and providing the latest research findings. At the end of this review, we also give some discussion and future perspectives regarding the challenges and opportunities in nobiletin efficient exploitation.

Vitamin D levels do not cause vitamin-drug interactions with dexamethasone or dasatinib in mice

Vitamin D3 (VD3) induces intestinal CYP3A that metabolizes orally administered anti-leukemic chemotherapeutic substrates dexamethasone (DEX) and dasatinib potentially causing a vitamin-drug interaction. To determine the impact of VD3 status on systemic exposure and efficacy of these chemotherapeutic agents, we used VD3 sufficient and deficient mice and performed pharmacokinetic and anti-leukemic efficacy studies. Female C57BL/6J and hCYP3A4 transgenic VD3 deficient mice had significantly lower duodenal (but not hepatic) mouse Cyp3a11 and hCYP3A4 expression compared to VD3 sufficient mice, while duodenal expression of Mdr1a, Bcrp and Mrp4 were significantly higher in deficient mice. When the effect of VD3 status on DEX systemic exposure was compared following a discontinuous oral DEX regimen, similar to that used to treat pediatric acute lymphoblastic leukemia patients, male VD3 deficient mice had significantly higher mean plasma DEX levels (31.7 nM) compared to sufficient mice (12.43 nM) at days 3.5 but not at any later timepoints. Following a single oral gavage of DEX, there was a statistically, but not practically, significant decrease in DEX systemic exposure in VD3 deficient vs. sufficient mice. While VD3 status had no effect on oral dasatinib's area under the plasma drug concentration-time curve, VD3 deficient male mice had significantly higher dasatinib plasma levels at t = 0.25 hr. Dexamethasone was unable to reverse the poorer survival of VD3 sufficient vs. deficient mice to BCR-ABL leukemia. In conclusion, although VD3 levels significantly altered intestinal mouse Cyp3a in female mice, DEX plasma exposure was only transiently different for orally administered DEX and dasatinib in male mice. Likewise, the small effect size of VD3 deficiency on single oral dose DEX clearance suggests that the clinical significance of VD3 levels on DEX systemic exposure are likely to be limited.

Enteral Medication for the Tube-Fed Patient: Making This Route Safe and Effective

The administration of medication through an enteral access device requires important forethought. Meeting a patient's therapeutic needs requires achieving expected drug bioavailability without increasing the risk for toxicity, therapeutic failure, or feeding tube occlusion. Superimposing gut dysfunction, critical illness, or enteral nutrition-drug interaction further increases the need for a systematic approach to prescribing, evaluating, and preparing a drug for administration through an enteral access device. This review will explain the fundamental factors involved in drug bioavailability through the gut, address the influencing considerations for the enterally fed patient, and describe best practices for enteral drug preparation and administration.

The effect of green tea catechins on breast cancer resistance protein activity and intestinal efflux of aflatoxin B1 via breast cancer resistance protein in Caco-2 cells

Aflatoxin B₁ (AFB₁), a mycotoxin produced by Aspergillus spp., was proved as one of the major causes of human hepatocellular carcinoma (HCC) when chronically consumed. An efflux of AFB₁ was reported to be associated with breast cancer resistance protein (BCRP) whose activity could also be modulated by green tea catechins. The purpose of this study was, therefore, to examine the impacts of green tea catechins on BCRP activity in Caco-2 cells by H33342 (bis-benzamide, BCRP substrate) accumulation and AFB₁ efflux. Results showed a significant decrease (p < 0.05) of AFB₁ in the efflux ratio following the incubation with Ko143, a specific BCRP inhibitor, and sodium fluoride, confirming the association of BCRP in AFB₁ efflux transport across the cells. Pre-incubation with green tea and gallate catechins (ECG and EGCG) significantly reduced the efflux ratio of AFB₁ (p < 0.05) and significantly increased the intracellular H33342 substrate (p < 0.05) in Caco-2 cells, clearly indicating the inhibitory effects of green tea and gallate catechins on BCRP function. Further study on H33342 accumulation revealed a dose-dependent increment of intracellular H33342 when co-administered with increasing concentrations of AFB₁. This result implied a possible role of AFB₁ as a BCRP competitive inhibitor. The findings from this study concluded the roles of BCRP as an efflux transporter for AFB₁ and could be modulated by the exposure of green tea catechins. Owing to a reduction of its efflux, an inhibitory effect of BCRP when pre-exposed with green tea catechins could be crucial for AFB₁ cellular accumulation.

Flavoured water consumption alters pharmacokinetic parameters and increases exposure of erlotinib and gefitinib in a preclinical study using Wistar rats

Background

Erlotinib (ERL) and Gefitinib (GEF) are considered first line therapy for the management of non-small cell lung carcinoma (NSCLC). Like other tyrosine kinase inhibitors (TKIs), ERL and GEF are mainly metabolized by the cytochrome P450 (CYP450) CYP3A4 isoform and are substrates for transporter proteins with marked inter-/intra-individual pharmacokinetic (PK) variability. Therefore, ERL and GEF are candidates for drug-drug and food-drug interactions with a consequent effect on drug exposure and/or drug-related toxicities. In recent years, the consumption of flavoured water (FW) has gained in popularity. Among multiple ingredients, fruit extracts, which might constitute bioactive flavonoids, can possess an inhibitory effect on the CYP450 enzymes or transporter proteins. Therefore, in this study we investigated the effects of different types of FW on the PK parameters of ERL and GEF in Wistar rats.

Methods

ERL and GEF PK parameters in different groups of rats after four weeks consumption of different flavours of FW, namely berry, peach, lime, and pineapple, were determined from plasma drug concentrations using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS).

Results

Data indicated that tested FWs altered the PK parameters of both ERL and GEF differently. Lime water had the highest impact on most of ERL and GEF PK parameters, with a significant increase in C_max (95% for ERL, 58% for GEF), AUC_0-48 (111% for ERL, 203% for GEF), and AUC_0-∞ (200% for ERL, 203% for GEF), along with a significant decrease in the apparent oral clearance of both drugs (65% for ERL, 67% for GEF). The order by which FW affected the PK parameters for ERL and GEF was as follows: lime > pineapple > berry > peach.

Conclusion

The present study indicates that drinking FW could be of significance in rats receiving ERL or GEF. Our results indicate that the alteration in PKs was mostly recorded with lime, resulting in an enhanced bioavailability, and reduced apparent oral clearance of the drugs. Peach FW had a minimum effect on the PK parameters of ERL and no significant effect on GEF PKs. Accordingly, it might be of clinical importance to evaluate the PK parameters of ERL and GEF in human subjects who consume FW while receiving therapy.

Effect of Green Tea and (-)-Epigallocatechin Gallate on the Pharmacokinetics of Rosuvastatin

BACKGROUND

Green tea can inhibit OATPs, so it may interact with the substrate of OATPs, such as rosuvastatin.

OBJECTIVE

This study aimed to investigate the effects of green tea on the pharmacokinetics of rosuvastatin and its mechanism.

METHODS

Male Sprague-Dawley rats received different doses of green tea extract (GTE) and (-)- epigallocatechin-3- gallate (EGCG). Caco-2 cells and OATP1B1-HEK293T cells were used in drug uptake and transport assay. The matrix concentrations of rosuvastatin and catechins were determined by ultra-performance liquid chromatographytandem mass spectrometry (UPLC-MS/MS).

RESULTS

GTE and EGCG were both found to increase the area under the plasma concentration-time curve (AUC0-∞) of rosuvastatin ((p<0.050). In the Caco-2 cell model, the uptake and transport of rosuvastatin in the GTE groups were 1.94-fold (p<0.001) and 2.11-fold (p<0.050) higher, respectively, than those of the control group. However, in the EGCG group, the uptake and transport of rosuvastatin were decreased by 22.62% and 44.19%, respectively (p<0.050). In the OATP1B1- HEK293T cell model, the OATP1B1-mediated rosuvastatin uptake was decreased by GTE to 35.02% of that in the control (p<0.050) and was decreased by EGCG to 45.61% of that in the control (p<0.050).

CONCLUSION

GTE increased the systemic rosuvastatin exposure in rats. The mechanism may include an increase in rosuvastatin absorption and a decrease in liver distribution by inhibiting OATP1B1. EGCG may be the main ingredient of green tea that affects the pharmacokinetic parameters of rosuvastatin. Our results showed the importance of conducting green tea-rosuvastatin study.

ADMET evaluation in drug discovery. 20. Prediction of breast cancer resistance protein inhibition through machine learning

Breast cancer resistance protein (BCRP/ABCG2), an ATP-binding cassette (ABC) efflux transporter, plays a critical role in multi-drug resistance (MDR) to anti-cancer drugs and drug–drug interactions. The prediction of BCRP inhibition can facilitate evaluating potential drug resistance and drug–drug interactions in early stage of drug discovery. Here we reported a structurally diverse dataset consisting of 1098 BCRP inhibitors and 1701 non-inhibitors. Analysis of various physicochemical properties illustrates that BCRP inhibitors are more hydrophobic and aromatic than non-inhibitors. We then developed a series of quantitative structure–activity relationship (QSAR) models to discriminate between BCRP inhibitors and non-inhibitors. The optimal feature subset was determined by a wrapper feature selection method named rfSA (simulated annealing algorithm coupled with random forest), and the classification models were established by using seven machine learning approaches based on the optimal feature subset, including a deep learning method, two ensemble learning methods, and four classical machine learning methods. The statistical results demonstrated that three methods, including support vector machine (SVM), deep neural networks (DNN) and extreme gradient boosting (XGBoost), outperformed the others, and the SVM classifier yielded the best predictions (MCC = 0.812 and AUC = 0.958 for the test set). Then, a perturbation-based model-agnostic method was used to interpret our models and analyze the representative features for different models. The application domain analysis demonstrated the prediction reliability of our models. Moreover, the important structural fragments related to BCRP inhibition were identified by the information gain (IG) method along with the frequency analysis. In conclusion, we believe that the classification models developed in this study can be regarded as simple and accurate tools to distinguish BCRP inhibitors from non-inhibitors in drug design and discovery pipelines.

Evaluation of inhibitory effects of flavonoids on breast cancer resistance protein (BCRP): From library screening to biological evaluation to structure-activity relationship

Flavonoids are a group of polyphenols ubiquitously present in vegetables, fruits and herbal products, despite various known pharmacological activities, few researches have been done about the interaction of flavonoids with breast cancer resistance protein (BCRP). The present study was designed to investigate the inhibitory effects of 99 flavonoids on BCRP in vitro and in vivo and to clarify structure-activity relationships of flavonoids with BCRP. Eleven flavonoids, including amentoflavone, apigenin, biochanin A, chrysin, diosimin, genkwanin, hypericin, kaempferol, kaempferide, licochalcone A and naringenin, exhibited significant inhibition (>50%) on BCRP in BCRP-MDCKII cells, which reduced the BCRP-mediated efflux of doxorubicin and temozolomide, accordingly increased their cytotoxicity. In addition, co-administration of mitoxantrone with the 11 flavonoids increased the AUC0-t of mitoxantrone in different extents in rats. Among them, chrysin increased the AUC0-t most significantly, by 81.97%. Molecular docking analysis elucidated the inhibition of flavonoids on BCRP might be associated with Pi-Pi stacked interactions and/or potential Pi-Alkyl interactions, but not conventional hydrogen bonds. The pharmacophore model indicated the aromatic ring B, hydrophobic groups and hydrogen bond acceptors may play critical role in the potency of flavonoids inhibition on BCRP. Thus, our findings would provide helpful information for predicting the potential risks of flavonoid-containing food/herb-drug interactions in humans.

Chloroquine sensitizes MDA-MB-231 cells to osimertinib through autophagy-apoptosis crosstalk pathway

Background: Triple-negative breast cancer (TNBC) is a breast cancer that tests negative for estrogen receptor (ER), progesterone receptors, and human epidermal growth factor receptors 2 (HER2). It is aggressive and invasive in nature and lacks targeted therapy. Purpose: The EGFR is frequently overexpressed in TNBC, and the EGFR-overexpressing TNBC presumably escapes EGFR inhibitor therapy by upregulating autophagy and inhibiting apoptosis. Methods: To parse the autophagy-apoptosis crosstalk pathway as a potential targeted therapy in TNBC, the activity of an EGFR inhibitor, osimertinib, alone and in combination with an autophagy inhibitor, chloroquine, was examined in EGFR-overexpressing TNBC cell line, MDA-MB-231. The nature of interaction between both drugs at various concentrations was determined by calculating combination indexes (CI) using CompuSyn software. Temporal changes in the expression of the autophagy marker, LC3B-II, and several apoptosis signaling molecules were measured using Western blot and luminex assay with MAGPIX® after exposure to drugs. A synergistic interaction (CI <1) was identified with combinations of 4-6.5 μM osimertinib with 30-75 μM chloroquine. Results: A combination of osimertinib (6 μM) with chloroquine (30 μM) resulted in a 6-fold increase of LC3B-II relative to control compared to 2.5-fold increase for either drug alone. The caspase-3 expression increased 2-fold compared to a 0.5-fold decrease with chloroquine and 1.5-fold increase with osimertinib. Conclusion: Our results indicate that inhibition of the autophagic flux via chloroquine improves the effectiveness of osimertinib in TNBC cancer cells, warranting further investigations of this combination in vivo.

Potential Influence of Centrally Acting Herbal Drugs on Transporters at the Blood-Cerebrospinal Fluid Barrier and Blood-Brain Barrier

Complementary and alternative medications (CAM) with known or suspected pharmacologic activity in the central nervous system (CNS) are common. These herbal preparations may cause clinically significant drug-drug interactions (DDIs) when coadministered with medications that act in the CNS. This can result in negative outcomes such as toxicity or loss of efficacy. Most drug interaction reports with CAM focus on cytochrome P450 (CYP) modulation. However, drug interactions between CAM and conventional medications may occur via mechanisms other than CYP inhibition or induction; in particular, modulation of drug transport proteins represents an important mechanism by which such interactions may occur. This article provides an updated review of transporter-mediated mechanisms by which herbal products may theoretically interact with centrally acting medications at the blood-brain barrier and blood-cerebrospinal fluid (CSF) barrier. Further research is required before the true clinical impact of interactions involving modulation of centrally located membrane transporters can be fully understood.

Food Bioactive Compounds and Their Interference in Drug Pharmacokinetic/Pharmacodynamic Profiles

Preclinical and clinical studies suggest that many food molecules could interact with drug transporters and metabolizing enzymes through different mechanisms, which are predictive of what would be observed clinically. Given the recent incorporation of dietary modifications or supplements in traditional medicine, an increase in potential food-drug interactions has also appeared. The objective of this article is to review data regarding the influence of food on drug efficacy. Data from Google Scholar, PubMed, and Scopus databases was reviewed for publications on pharmaceutical, pharmacokinetic, and pharmacodynamic mechanisms. The following online resources were used to integrate functional and bioinformatic results: FooDB, Phenol-Explorer, Dr. Duke's Phytochemical and Ethnobotanical Databases, DrugBank, UniProt, and IUPHAR/BPS Guide to Pharmacology. A wide range of food compounds were shown to interact with proteins involved in drug pharmacokinetic/pharmacodynamic profiles, starting from drug oral bioavailability to enteric/hepatic transport and metabolism, blood transport, and systemic transport/metabolism. Knowledge of any food components that may interfere with drug efficacy is essential, and would provide a link for obtaining a holistic view for cancer, cardiovascular, musculoskeletal, or neurological therapies. However, preclinical interaction may be irrelevant to clinical interaction, and health professionals should be aware of the limitations if they intend to optimize the therapeutic effects of drugs.

Beneficial Pharmacokinetic Drug Interactions: A Tool to Improve the Bioavailability of Poorly Permeable Drugs

Simultaneous oral intake of herbs, supplements, foods and drugs with other drug(s) may result in pharmacokinetic or pharmacodynamic interactions with the latter. Although these interactions are often associated with unwanted effects such as adverse events or inefficacy, they can also produce effects that are potentially beneficial to the patient. Beneficial pharmacokinetic interactions include the improvement of the bioavailability of a drug (i.e., by enhancing absorption and/or inhibiting metabolism) or prolongation of a drug's plasma level within its therapeutic window (i.e., by decreasing excretion), whereas beneficial pharmacodynamic interactions include additive or synergistic effects. Mechanisms by which pharmacokinetic interactions can cause beneficial effects include enhancement of membrane permeation (e.g., structural changes in the epithelial cell membranes or opening of tight junctions), modulation of carrier proteins (e.g., inhibition of efflux transporters and stimulation of uptake transporters) and inhibition of metabolic enzymes. In the current review, selected pharmacokinetic interactions between drugs and various compounds from different sources including food, herb, dietary supplements and selected drugs are discussed. These interactions may be exploited in the future to the benefit of the patient, for example, by delivering drugs that are poorly bioavailable in therapeutic levels via alternative routes of administration than parenteral injection.

Validated UPLC-MS/MS method for the quantification of dasatinib in plasma: Application to pharmacokinetic interaction studies with nutraceuticals in Wistar rats

Dasatinib (DAS) is a tyrosine kinase inhibitor (TKI) used in the treatment of chronic myeloid leukemia and in the management of ulcerative colitis (UC). Since some nutraceuticals (e.g. curcumin, olive oil, and cocoa extract) could alter the function of ABC transporters and /or CYP450 enzymes, DAS bioavailability could potentially be affected following their co-administration. This work aims at studying the possibility of PK interaction between DAS and the selected nutraceuticals in UC rats using UPLC- MS/MS. Chromatographic analysis was carried out using BEH C 18 column (Waters) with a mobile phase consisting of acetonitrile and 50% aqueous methanol, 65:35, v/v, each with 0.1% formic acid and using erlotinib (ERL) as an internal standard (IS). DAS quantitation was carried out using multiple reaction monitoring (MRM) with positive ionization of the transitions at m/z 488.03 > 400.92 (DAS), and m/z 394.29 > 278.19 (ERL). Method validation was assessed as per the FDA guidelines for bioanalytical methods for DAS determination within the concentration range 1–500 ng/mL. No significant effect on the oral bioavailability of DAS was reported with any of the studied nutraceuticals. Thus, the concomitant administration of these nutraceuticals with DAS could be considered safe with a necessity to perform more detailed clinical investigations.

Causes and Consequences of Variability in Drug Transporter Activity in Pediatric Drug Therapy

Drug transporters play a key role in mediating the uptake of endo- and exogenous substances into cells as well as their efflux. Therefore, variability in drug transporter activity can influence pharmaco- and toxicokinetics and be a determinant of drug safety and efficacy. In children, particularly in neonates and young infants, the contribution of tissue-specific drug transporters to drug absorption, distribution, and excretion may differ from that in adults. In this review 5 major factors and their interdependence that may influence drug transporter activity in children are discussed: developmental differences, genetic polymorphisms, pediatric comorbidities, interacting comedication, and environmental factors. Even if data are sparse, altered drug transporter activity due to those factors have been associated with clinically relevant differences in drug disposition, efficacy, and safety in pediatric patients. Single nucleotide polymorphisms in drug transporter-encoding genes were the most studied source of drug transporter variability in children. However, in the age group where drug transporter activity has been reported to differ from that in adults, namely neonates and young infants, hardly any studies have been performed. Longitudinal studies in this young population are required to investigate the age- and disease-dependent genotype-phenotype relationships and relevance of drug transporter drug-drug interactions. Physiologically based pharmacokinetic modeling approaches can integrate drug- and patient-specific parameters, including drug transporter ontogeny, and may further improve in silico predictions of pediatric-specific pharmacokinetics.

Renal Drug Transporters and Drug Interactions

Transporters in proximal renal tubules contribute to the disposition of numerous drugs. Furthermore, the molecular mechanisms of tubular secretion have been progressively elucidated during the past decades. Organic anions tend to be secreted by the transport proteins OAT1, OAT3 and OATP4C1 on the basolateral side of tubular cells, and multidrug resistance protein (MRP) 2, MRP4, OATP1A2 and breast cancer resistance protein (BCRP) on the apical side. Organic cations are secreted by organic cation transporter (OCT) 2 on the basolateral side, and multidrug and toxic compound extrusion (MATE) proteins MATE1, MATE2/2-K, P-glycoprotein, organic cation and carnitine transporter (OCTN) 1 and OCTN2 on the apical side. Significant drug-drug interactions (DDIs) may affect any of these transporters, altering the clearance and, consequently, the efficacy and/or toxicity of substrate drugs. Interactions at the level of basolateral transporters typically decrease the clearance of the victim drug, causing higher systemic exposure. Interactions at the apical level can also lower drug clearance, but may be associated with higher renal toxicity, due to intracellular accumulation. Whereas the importance of glomerular filtration in drug disposition is largely appreciated among clinicians, DDIs involving renal transporters are less well recognized. This review summarizes current knowledge on the roles, quantitative importance and clinical relevance of these transporters in drug therapy. It proposes an approach based on substrate-inhibitor associations for predicting potential tubular-based DDIs and preventing their adverse consequences. We provide a comprehensive list of known drug interactions with renally-expressed transporters. While many of these interactions have limited clinical consequences, some involving high-risk drugs (e.g. methotrexate) definitely deserve the attention of prescribers.

Multidrug-resistant cancer cells and cancer stem cells hijack cellular systems to circumvent systemic therapies, can natural products reverse this?

Chemotherapy is one of the most effective and broadly used approaches for cancer management and many modern regimes can eliminate the bulk of the cancer cells. However, recurrence and metastasis still remain a major obstacle leading to the failure of systemic cancer treatments. Therefore, to improve the long-term eradication of cancer, the cellular and molecular pathways that provide targets which play crucial roles in drug resistance should be identified and characterised. Multidrug resistance (MDR) and the existence of tumor-initiating cells, also referred to as cancer stem cells (CSCs), are two major contributors to the failure of chemotherapy. MDR describes cancer cells that become resistant to structurally and functionally unrelated anti-cancer agents. CSCs are a small population of cells within cancer cells with the capacity of self-renewal, tumor metastasis, and cell differentiation. CSCs are also believed to be associated with chemoresistance. Thus, MDR and CSCs are the greatest challenges for cancer chemotherapy. A significant effort has been made to identify agents that specifically target MDR cells and CSCs. Consequently, some agents derived from nature have been developed with a view that they may overcome MDR and/or target CSCs. In this review, natural products-targeting MDR cancer cells and CSCs are summarized and clustered by their targets in different signaling pathways.

Effect of Tea Polyphenol Compounds on Anticancer Drugs in Terms of Anti-Tumor Activity, Toxicology, and Pharmacokinetics

Multidrug resistance and various adverse side effects have long been major problems in cancer chemotherapy. Recently, chemotherapy has gradually transitioned from mono-substance therapy to multidrug therapy. As a result, the drug cocktail strategy has gained more recognition and wider use. It is believed that properly-formulated drug combinations have greater therapeutic efficacy than single drugs. Tea is a popular beverage consumed by cancer patients and the general public for its perceived health benefits. The major bioactive molecules in green tea are catechins, a class of flavanols. The combination of green tea extract or green tea catechins and anticancer compounds has been paid more attention in cancer treatment. Previous studies demonstrated that the combination of chemotherapeutic drugs and green tea extract or tea polyphenols could synergistically enhance treatment efficacy and reduce the adverse side effects of anticancer drugs in cancer patients. In this review, we summarize the experimental evidence regarding the effects of green tea-derived polyphenols in conjunction with chemotherapeutic drugs on anti-tumor activity, toxicology, and pharmacokinetics. We believe that the combination of multidrug cancer treatment with green tea catechins may improve treatment efficacy and diminish negative side effects.

Phytochemical mediated-modulation of the expression and transporter function of breast cancer resistance protein at the blood-brain barrier: An in-vitro study

Clinical translation of BCRP inhibitors have failed due to neurotoxicity and novel approaches are required to identify suitable modulators of BCRP to enhance CNS drug delivery. In this study we examine 18 compounds, primarily phytochemicals, as potential novel modulators of AhR-mediated regulation of BCRP expression and function in immortalised and primary porcine brain microvascular endothelial cells as a mechanism to enhance CNS drug delivery. The majority of modulators possessed a cellular viability IC₅₀ >100µm in both cell systems. BCRP activity, when exposed to modulators for 1h, was diminished for most modulators through significant increases in H33342 accumulation at <10µm with 2,6,4-trimethoflavone increasing H33342 intracellular accumulation by 3.7-6.6 fold over 1-100µm. Western blotting and qPCR identified two inducers of BCRP (quercetin and naringin) and two down-regulators (17-β-estradiol and curcumin) with associated changes in BCRP efflux transport function further confirmed in both cell lines. siRNA downregulation of AhR resulted in a 1.75±0.08 fold change in BCRP expression, confirming the role of AhR in the regulation of BCRP. These findings establish the regulatory role AhR of in controlling BCRP expression at the BBB and confirm quercetin, naringin, 17-β-estradiol, and curcumin as novel inducers and down-regulators of BCRP gene, protein expression and functional transporter activity and hence potential novel target sites and candidates for enhancing CNS drug delivery.

The Multifunctional Effects of Nobiletin and Its Metabolites In Vivo and In Vitro

Nobiletin (NOB) chemically known as 5,6,7,8,3′,4′-hexamethoxyflavone is a dietary polymethoxylated flavonoid found in Citrus fruits. Recent evidences show that NOB is a multifunctional pharmaceutical agent. The various pharmacological activities of NOB include neuroprotection, cardiovascular protection, antimetabolic disorder, anticancer, anti-inflammation, and antioxidation. These events may be underpinned by modulation of signaling cascades, including PKA/ERK/MEK/CREB, NF-κB, MAPK, Ca²⁺/CaMKII, PI3K/Akt1/2, HIF-1α, and TGFβ signaling pathways. The metabolites may exhibit stronger beneficial effects than NOB on diseases pathogenesis. The biological activities of NOB have been clarified on many systems. This review aims to discuss the pharmacological effects of NOB with specific mechanisms of actions. NOB may become a promising candidate for potential drug development. However, further investigations of NOB on specific intracellular targets and clinical trials are still needed, especially for in vivo medical applications.

TKI combination therapy: strategy to enhance dasatinib uptake by inhibiting Pgp- and BCRP-mediated efflux

The overexpression of efflux transporters, especially P-glycoprotein (Pgp, MDR1, ABCB1) and breast cancer resistance protein (BCRP, ABCG2), represents an important mechanism of multidrug resistance (MDR). Tyrosine kinase inhibitors (TKIs), a novel group of target-specific anticancer drugs, have recently been found to interact with Pgp and BCRP and to serve as both substrates and inhibitors. Considering their dual role, we anticipate that combination TKI therapy may represent a promising strategy to reverse efflux transporter mediated TKI resistance. Presently, investigations on these interactions are very limited. To fill the literature gap, dasatinib was used as the model drug and the effects of various TKIs on Pgp- and BCRP- mediated dasatinib efflux were evaluated. Cell uptake studies were performed using LLC-PK1 and MDCK-II cells along with their subclones that were transfected with human Pgp and BCRP, respectively. Among the 14 TKIs screened, nine TKIs greatly inhibited Pgp-mediated dasatinib efflux at 50 μm. Further concentration dependent studies showed that imatinib, nilotinib and pazopanib were potent Pgp inhibitors with IC₅₀ values of 2.42, 6.11 and 8.06 μm, respectively. Additionally, 50 μm of five TKIs greatly increased dasatinib accumulation through BCRP inhibition. Concentration dependent studies revealed that imatinib, erlotinib, nilotinib, axitinib and pazopanib were potent BCRP inhibitors with IC₅₀ values of 0.94, 2.23, 2.50, 6.89 and 10.4 μm, respectively. Our findings point to potential combinations of TKIs that could enhance intracellular concentrations of the targeted TKI, overcome MDR and improve TKI efficacy. Further in vivo studies are warranted to confirm the efflux transporter-mediated TKI-TKI interaction. Copyright © 2016 John Wiley & Sons, Ltd.

Phytochemical-loaded mesoporous silica nanoparticles for nose-to-brain olfactory drug delivery

Central nervous system (CNS) drug delivery is often hampered due to the insidious nature of the blood-brain barrier (BBB). Nose-to-brain delivery via olfactory pathways have become a target of attention for drug delivery due to bypassing of the BBB. The antioxidant properties of phytochemicals make them promising as CNS active agents but possess poor water solubility and limited BBB penetration. The primary aim of this study was the development of mesoporous silica nanoparticles (MSNs) loaded with the poorly water-soluble phytochemicals curcumin and chrysin which could be utilised for nose-to-brain delivery. We formulated spherical MSNP using a templating approach resulting in ∼220nm particles with a high surface porosity. Curcumin and chrysin were successfully loaded into MSNP and confirmed through Fourier transformation infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and HPLC approaches with a loading of 11-14% for curcumin and chrysin. Release was pH dependant with curcumin demonstrating increased chemical stability at a lower pH (5.5) with a release of 53.2%±2.2% over 24h and 9.4±0.6% for chrysin. MSNP were demonstrated to be non-toxic to olfactory neuroblastoma cells OBGF400, with chrysin (100μM) demonstrating a decrease in cell viability to 58.2±8.5% and curcumin an IC₅₀ of 33±0.18μM. Furthermore confocal microscopy demonstrated nanoparticles of <500nm were able to accumulate within cells with FITC-loaded MSNP showing membrane localised and cytoplasmic accumulation following a 2h incubation. MSNP are useful carriers for poorly soluble phytochemicals and provide a novel vehicle to target and deliver drugs into the CNS and bypass the BBB through olfactory drug delivery.

Effect of HM30181 mesylate salt-loaded microcapsules on the oral absorption of paclitaxel as a novel P-glycoprotein inhibitor

The purpose of this study was to develop HM30181 mesylate salt (HM30181M)-loaded microcapsules as a novel P-glycoprotein inhibitor for enhancing the oral absorption of paclitaxel. The effect of various carriers including hydrophilic polymers and solvents on the solubility of HM30181M were evaluated. Among the hydrophilic polymers and solvents tested, HPMC and methylene chloride (and ethanol) provided the highest HM30181M solubility. Numerous HM30181M-loaded microcapsules were prepared with HPMC, silicon dioxide and acidifying agents using a spray-drying technique, and their solubility, dissolution and physicochemical properties were evaluated. Furthermore, a pharmacokinetic study was performed after oral administration of paclitaxel alone, simultaneously with HM30181M powder or HM30181M-loaded microcapsules to rats. Among the acidifying agents investigated, phosphoric acid provided the best improvement in the solubility and dissolution of HM30181M. Moreover, the microcapsule composed of HM30181M, HPMC, silicon dioxide and phosphoric acid at a weight ratio of 3:6:3:2 remarkably enhanced the solubility and dissolution of HM30181M compared with the HM30181M powder alone. The microcapsules were spherical in shape, had a reduced particle size of about 7μm, and contained HM30181M in an amorphous state. Furthermore, this microcapsule significantly enhanced HM30181M absorption, making it about 1.7-fold faster and 1.6-fold greater after simultaneous administration, leading to about 70- and 2-fold improved oral bioavailability of paclitaxel compared with paclitaxel alone and the simultaneous administration with HM30181M powder, respectively. Thus, this novel microcapsule could be a potential candidate for effective P-glycoprotein inhibition during oral administration of paclitaxel.

Inhibitory Effects of Green Tea and (-)-Epigallocatechin Gallate on Transport by OATP1B1, OATP1B3, OCT1, OCT2, MATE1, MATE2-K and P-Glycoprotein

Green tea catechins inhibit the function of organic anion transporting polypeptides (OATPs) that mediate the uptake of a diverse group of drugs and endogenous compounds into cells. The present study was aimed at investigating the effect of green tea and its most abundant catechin epigallocatechin gallate (EGCG) on the transport activity of several drug transporters expressed in enterocytes, hepatocytes and renal proximal tubular cells such as OATPs, organic cation transporters (OCTs), multidrug and toxin extrusion proteins (MATEs), and P-glycoprotein (P-gp). Uptake of the typical substrates metformin for OCTs and MATEs and bromosulphophthalein (BSP) and atorvastatin for OATPs was measured in the absence and presence of a commercially available green tea and EGCG. Transcellular transport of digoxin, a typical substrate of P-gp, was measured over 4 hours in the absence and presence of green tea or EGCG in Caco-2 cell monolayers. OCT1-, OCT2-, MATE1- and MATE2-K-mediated metformin uptake was significantly reduced in the presence of green tea and EGCG (P < 0.05). BSP net uptake by OATP1B1 and OATP1B3 was inhibited by green tea [IC₅₀ 2.6% (v/v) and 0.39% (v/v), respectively]. Green tea also inhibited OATP1B1- and OATP1B3-mediated atorvastatin net uptake with IC₅₀ values of 1.9% (v/v) and 1.0% (v/v), respectively. Basolateral to apical transport of digoxin was significantly decreased in the presence of green tea and EGCG. These findings indicate that green tea and EGCG inhibit multiple drug transporters in vitro. Further studies are necessary to investigate the effects of green tea on prototoypical substrates of these transporters in humans, in particular on substrates of hepatic uptake transporters (e.g. statins) as well as on P-glycoprotein substrates.

Aristolochic acid I is a substrate of BCRP but not P-glycoprotein or MRP2

ETHNOPHARMACOLOGICAL RELEVANCE

Aristolochic acid nephropathy is a severe kidney disease caused by the administration of aristolochic acid, which is widely existed in plants of the Aristolochiaceae family. Aristolochic acid I (AAI) is the main toxic component in aristolochic acid.

AIM OF THE STUDY

The roles of intestinal efflux drug transporters in the transport of AAI are unclear. This study investigates the interaction between AAI and main intestinal efflux transporters.

MATERIALS AND METHODS

Firstly, bidirectional transport of AAI in Caco-2 cell monolayers was investigated. Then, MDCK-MDR1 (gene of P-glycoprotein (P-gp)), MDCK-MRP2 and LLC-PK1-BCRP cell lines were used for further investigation.

RESULTS

In this study, we observed that the efflux ratio of AAI in Caco-2 cell monolayers was 5.8, which indicated that efflux transporters might be involved in the transport of AAI. AAI did not inhibit Rho123 efflux by P-gp and calcein efflux by MRP2, and intracellular accumulation of AAI in P-gp or MRP2 overexpressing cells was not different from their parental cells. These results indicated that AAI was not a substrate of P-gp or MRP2. In contrast, intracellular accumulation of AAI in LLC-PK1-BCRP cells was significantly lower than in their parental cells. The presence of GF120918, a BCRP inhibitor, significantly increased AAI accumulation in BCRP overexpressing cells but not in their parental cells. In addition, bidirectional transport assay of AAI in LLC-PK1-BCRP monolayers showed that the net efflux ratios of AAI were 13.8, 8.0 and 7.0 at 20, 40 and 80 µM AAI, respectively, and decreased to 3.0, 1.9 and 2.0 by the addition of 10 µM GF120918.

CONCLUSIONS

These results indicated that AAI was a substrate of BCRP but not P-gp or MRP2.