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Cutaneous Ulcer Caused by Apixaban Treatment Is Resolved after Replacement with Dabigatran. MEDICINA (KAUNAS, LITHUANIA) 2022; 58:medicina58050691. [PMID: 35630109 PMCID: PMC9146744 DOI: 10.3390/medicina58050691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 05/19/2022] [Accepted: 05/20/2022] [Indexed: 11/24/2022]
Abstract
Nowadays, novel oral anticoagulants (NOACs) have shown improved safety profile and efficacy compared to vitamin K antagonists in the prevention of thromboembolic events occurring during different pathological conditions. However, there are concerns and safety issues, mostly related to adverse events following interactions with other drugs, in real-world practice. We report the case of an 83-year-old woman who developed a non-bleeding leg ulcer not caused by trauma or other evident pathological conditions after 10 days of treatment with apixaban 5 mg/q.d. She was switched from apixaban to dabigatran and the leg ulcer rapidly improved and completely cicatrized in 40 days. The resolution of the ulcer and the toleration of dabigatran therapy suggest an apixaban-specific reaction; however, the pathological mechanism of ulcer onset is currently unclear. Careful evaluation of hospital databases of Molise region (Southern Italy) hospitals identified two similar cases between 2019 and 2021. These cases underline the necessity of careful post-marketing surveillance, considering the rapidly increasing number of patients treated with NOACs and patient’s risk factors such as old age, high polypharmacy rate, co-morbidities, and peculiar genetic background related to NOACs pharmacokinetic features.
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Influence of Amlodipine on the Disposition of Quinine in Healthy Volunteers. Am J Ther 2020; 29:e115-e118. [PMID: 33021550 DOI: 10.1097/mjt.0000000000001249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Park J, Kim K, Il Kim Y, Park J. Pharmacokinetic and haemodynamic interactions between amlodipine and losartan in human beings. Basic Clin Pharmacol Toxicol 2019; 125:345-352. [DOI: 10.1111/bcpt.13244] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 04/17/2019] [Indexed: 11/30/2022]
Affiliation(s)
- Jin‐Woo Park
- Department of Clinical Pharmacology and Toxicology, Korea University College of Medicine Korea University Anam Hospital Seoul Republic of Korea
| | - Kyoung‐Ah Kim
- Department of Clinical Pharmacology and Toxicology, Korea University College of Medicine Korea University Anam Hospital Seoul Republic of Korea
| | - Yong Il Kim
- Pharmaceutical Research Center Hanmi Pharm. Co. Gyeonggi‐Do Republic of Korea
| | - Ji‐Young Park
- Department of Clinical Pharmacology and Toxicology, Korea University College of Medicine Korea University Anam Hospital Seoul Republic of Korea
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Effects of hydrochlorothiazide and amlodipine on single oral dose pharmacokinetics of valsartan in healthy Korean subjects: Population model-based approach. Eur J Pharm Sci 2018; 118:154-164. [DOI: 10.1016/j.ejps.2018.03.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 03/09/2018] [Accepted: 03/28/2018] [Indexed: 01/11/2023]
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Effects of orally administered antibiotics on the bioavailability of amlodipine: gut microbiota-mediated drug interaction. J Hypertens 2016; 34:156-62. [PMID: 26630218 DOI: 10.1097/hjh.0000000000000773] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
BACKGROUND Amlodipine is a representative calcium channel blocker that is frequently prescribed for the treatment of hypertension. In this study, the possibility of drug-drug interactions between amlodipine and coadministered antibiotics (ampicillin) was investigated in rats; thus, changes in the metabolic activities of gut microflora and the consequent pharmacokinetic pattern of amlodipine following ampicillin treatment were characterized. METHODS AND RESULTS In human and rat fecalase incubation samples, amlodipine was metabolized to yield a major pyridine metabolite. The remaining amlodipine decreased and the formation of pyridine metabolite increased with incubation time, indicating the involvement of gut microbiota in the metabolism of amlodipine. Pharmacokinetic analyses showed that systemic exposure of amlodipine was significantly elevated in antibiotic-treated rats compared with controls. CONCLUSION These results showed that antibiotic intake might increase the bioavailability of amlodipine by suppressing gut microbial metabolic activities, which could be followed by changes in therapeutic potency. Therefore, coadministration of amlodipine with antibiotics requires caution and clinical monitoring.
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Kohan HG, Boroujerdi M. Time and concentration dependency of P-gp, MRP1 and MRP5 induction in response to gemcitabine uptake in Capan-2 pancreatic cancer cells. Xenobiotica 2015; 45:642-52. [PMID: 25564970 DOI: 10.3109/00498254.2014.1001809] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
1. Influx and efflux proteins play a major role in the overall uptake and efficacy of chemotherapeutic agents and cellular chemo-resistance. 2. The present study investigated the time course and dose dependency of the induction of three efflux proteins, P-gp, MRP1 and MRP5, in response to gemcitabine exposure in Capan-2 pancreatic cancer cell line at transcriptional and translational levels. The influence of exposure on the influx protein (ENT1), the net cellular uptake of the gemcitabine, the overall ATPase activity and the cell death rate were also measured. 3. The time course of the expression exhibited an initial rise, toward a plateau level. The estimated Km and Vmax confirmed that MRP5 and to a lesser extent MRP1 are the prominent proteins for efflux of gemcitabine. Both mRNA and protein expression demonstrated the time and concentration dependency of the induction; and the elevated ATPase activity validated that the induced efflux proteins are functionally active. 4. The results of the study revealed that the efficacy window of gemcitabine as it relates to the function of the efflux proteins is concentration and temporal dependent and is well correlated to the first 60 min of exposure.
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Affiliation(s)
- Hamed Gilzad Kohan
- Department of Pharmaceutical Sciences, Albany College of Pharmacy and Health Sciences , Albany, NY , USA
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Fumoleau P, Koch KM, Brain E, Lokiec F, Rezai K, Awada A, Hayward L, Werutsky G, Bogaerts J, Marréaud S, Cardoso F. A phase I pharmacokinetics study of lapatinib and tamoxifen in metastatic breast cancer (EORTC 10053 Lapatam study). Breast 2014; 23:663-9. [PMID: 25065668 DOI: 10.1016/j.breast.2014.07.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Revised: 07/01/2014] [Accepted: 07/07/2014] [Indexed: 10/25/2022] Open
Abstract
OBJECTIVE This phase I study assessed the pharmacokinetic (PK), tolerability, safety and preliminary clinical activity of tamoxifen (T) and lapatinib (L) in patients with metastatic breast cancer (MBC). METHODS Patients (pts) with hormone receptor positive MBC, irrespective of HER-2 status, were randomly assigned to T → T + L group, tamoxifen in cycle 1 for 28 days then adding lapatinib on day 1 of cycle 2; or L → T + L group, lapatinib in cycle 1 for 14 days, then adding tamoxifen on day 1 of cycle 2 to evaluate the potential drug-drug PK interaction at steady-state. The dose of tamoxifen was 20 mg/day and lapatinib 1500 mg/day. RESULTS Twenty-five pts were enrolled of which 23 started treatment, five (22%) of them were HER-2 positive. Median age was 59 years and 96% had PS ≤1. Eleven (91.7%) pts in the T → T + L group and 10 (76.9%) in L → T + L group received at least 2 cycles of treatment. The most frequently reported drug-related adverse events (>25% of patients) were diarrhoea (62%), anaemia (56%), rash (52%), fatigue (52%), dermatology other (34%) and leukopenia (28%). Grade 3-4 drug-related toxicities were infrequent (<10%). No cardiotoxicity was observed. T plasma concentrations did not appeared to be affected by the presence of lapatinib. L steady-state plasma concentrations were 20% lower after 28 days of co-administration with T. Eight (36.4%) patients experienced stable disease and median progression free survival was 2.7 months. CONCLUSIONS The combination of L and T was safe and clinically active. T affected L plasma concentrations, which remained within the therapeutic index.
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Affiliation(s)
- Pierre Fumoleau
- Centre Georges-François Leclerc, Rue Professeur Marion, 21079 Dijon, France.
| | - Kevin M Koch
- GlaxoSmithKline, Research Triangle Park, 5 Moore Drive, 27709 Raleigh-Durham, United States.
| | - Etienne Brain
- Institut Curie, Centre René Huguenin, 35 rue Dailly, 92210 Saint-Cloud, France.
| | - François Lokiec
- Institut Curie, Centre René Huguenin, 35 rue Dailly, 92210 Saint-Cloud, France.
| | - Keyvan Rezai
- Institut Curie, Centre René Huguenin, 35 rue Dailly, 92210 Saint-Cloud, France.
| | - Ahmad Awada
- Institut Jules Bordet, Boulevard de Waterloo 121, 1000 Brussels, Belgium.
| | - Larry Hayward
- Edinburgh Cancer Centre, Western General Hospital, Crewe Road South, EH4 2XR Edinburgh, United Kingdom.
| | - Gustavo Werutsky
- European Organisation for Research and Treatment of Cancer, Avenue Mounier, 83/11, 1200 Brussels, Belgium.
| | - Jan Bogaerts
- European Organisation for Research and Treatment of Cancer, Avenue Mounier, 83/11, 1200 Brussels, Belgium.
| | - Sandrine Marréaud
- European Organisation for Research and Treatment of Cancer, Avenue Mounier, 83/11, 1200 Brussels, Belgium.
| | - Fatima Cardoso
- Institut Jules Bordet, Boulevard de Waterloo 121, 1000 Brussels, Belgium; Institut Jules Bordet (currently at Champalimaud Cancer Center), Av. de Brasília, s/n, 1400-038 Lisbon, Portugal.
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Mater N, Geret F, Castillo L, Faucet-Marquis V, Albasi C, Pfohl-Leszkowicz A. In vitro tests aiding ecological risk assessment of ciprofloxacin, tamoxifen and cyclophosphamide in range of concentrations released in hospital wastewater and surface water. ENVIRONMENT INTERNATIONAL 2014; 63:191-200. [PMID: 24317225 DOI: 10.1016/j.envint.2013.11.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 11/06/2013] [Accepted: 11/14/2013] [Indexed: 06/02/2023]
Abstract
Ciprofloxacin (CIP), tamoxifen (TAM) and cyclophosphamide (CP) which are often used in anticancer treatment are released in hospital effluent and into the environment. Although the concentrations are low (from ng/L to μg/L), no data exist concerning their ecotoxicological impact. In this study two biomarkers of early effect were performed on hepatic cells (HepG2): cell viability and genotoxicity (DNA breaks) using cell proliferative assay and comet assay, respectively. These data were compared with two standardized ecotoxicological tests: algaltoxkit F™ and microtox®. Cells were exposed to an increasing amount of an individual drug or in a mixture for 24, 48 or 72h. The time-exposure of bacteria and algae ranged between 5 and 30min and 72h, respectively. A non-monotonic dose-response on cell viability was observed when HepG2 cells were exposed to TAM alone or in the presence of CIP. The same scheme was observed with microtox® when the bacteria were exposed to the mixtures. On the other side, an individual drug does not induce any DNA breaks on hepatic cells, whereas a mixture leads to a dose dependent increase of DNA breaks. Similarly a positive response was observed with algaltoxkit F™ only with mixtures. Synergistic effects observed when drugs are in a mixture highlight the importance of investigating the ecotoxicological effects of contaminants at low concentrations and in mixtures.
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Affiliation(s)
- N Mater
- Université de Toulouse, Institut National Polytechnique, Laboratoire de Génie Chimique, UMR CNRS/INPT/UPS 5503, France; Ecole Nationale Supérieure Agronomique (ENSAT), 1 avenue Agrobiopôle, BP 32607, 31320 Auzeville-Tolosane, France
| | - F Geret
- Université de Toulouse, Laboratoire GEODE, UMR CNRS 5602, Centre Universitaire Jean-François Champollion, Place de Verdun, 81012 Albi cedex 9, France
| | - L Castillo
- Veolia Environnement Recherche et Innovation, Centre de Recherche de Maisons Laffitte, 78603 Maisons Laffitte, France
| | - V Faucet-Marquis
- Université de Toulouse, Institut National Polytechnique, Laboratoire de Génie Chimique, UMR CNRS/INPT/UPS 5503, France; Ecole Nationale Supérieure Agronomique (ENSAT), 1 avenue Agrobiopôle, BP 32607, 31320 Auzeville-Tolosane, France
| | - C Albasi
- Université de Toulouse, Institut National Polytechnique, Laboratoire de Génie Chimique, UMR CNRS/INPT/UPS 5503, France; Ecole National Supérieure des Ingénieurs en Arts chimiques et Technologiques (ENSIACET), 4 allée Emile Monso, 31030 Toulouse cedex 4, France
| | - A Pfohl-Leszkowicz
- Université de Toulouse, Institut National Polytechnique, Laboratoire de Génie Chimique, UMR CNRS/INPT/UPS 5503, France; Ecole Nationale Supérieure Agronomique (ENSAT), 1 avenue Agrobiopôle, BP 32607, 31320 Auzeville-Tolosane, France.
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He YL, Ligueros-Saylan M, Sunkara G, Sabo R, Zhao C, Wang Y, Campestrini J, Pommier F, Dole K, Marion A, Dole WP, Howard D. Vildagliptin, a Novel Dipeptidyl Peptidase IV Inhibitor, Has No Pharmacokinetic Interactions With the Antihypertensive Agents Amlodipine, Valsartan, and Ramipril in Healthy Subjects. J Clin Pharmacol 2013; 48:85-95. [DOI: 10.1177/0091270007307880] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Choi DH, Piao YJ, Choi EJ, Choi JS, Burm JP. Effects of Amlodipine on the Pharmacokinetics of Warfarin after Oral and Intravenous Administration of Warfarin in Rats. Biomol Ther (Seoul) 2011. [DOI: 10.4062/biomolther.2011.19.4.493] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Choi DH, Choi JS. Pharmacokinetic Interaction between Warfarin and Efonidipine in Rats. JOURNAL OF PHARMACEUTICAL INVESTIGATION 2011. [DOI: 10.4333/kps.2011.41.5.273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Zarrin A, Mehdipour AR, Miri R. Dihydropyridines and multidrug resistance: previous attempts, present state, and future trends. Chem Biol Drug Des 2011; 76:369-81. [PMID: 20925689 DOI: 10.1111/j.1747-0285.2010.01025.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Multidrug resistance is defined as the resistance of a tumor cell to the cytotoxic action of divergent drugs used in chemotherapy. Dihydropyridines are a class of calcium channel antagonists that were discovered to have a multidrug resistance reversing effect and prompted investigations resulting in the synthesis of hundreds of new derivatives. Most of the investigators tried to achieve two goals: a decrease in Ca²(+) channel-blocking activity and an increase in the multidrug resistance reversing effect. Most of the synthesized compounds failed in the later stages of studies especially in clinical trials because of pharmacokinetic or pharmacodynamic limitations. Therefore, it will be necessary to include new methods, such as combinatorial synthesis, and, more importantly, to apply computational methods based on global structure-activity relationship models that consider all problems. Moreover, some compounds should be synthesized that are effective on several multidrug resistance targets.
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Affiliation(s)
- Abdolhossein Zarrin
- Medicinal & Natural Products Chemistry Research Center, Shiraz University of Medical Sciences, Iran
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Calabrese EJ. P-glycoprotein efflux transporter activity often displays biphasic dose-response relationships. Crit Rev Toxicol 2008; 38:473-87. [PMID: 18568867 DOI: 10.1080/10408440802004049] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The occurrence of P-glycoprotein efflux transporter systems is recognized as playing critical roles in chemotherapy, drug pharmacokinetics, and the bioavailability of environmental toxins. This article reveals that P-glycoprotein efflux transporter activity commonly displays a biphasic dose response, with low doses being stimulatory and high doses inhibiting. The quantitative features of these biphasic dose responses are consistent with the hormetic dose-response model and are independent of biological model and chemical class. These findings provide further support for the generalizability of the hormetic dose-response model while having important biological and clinical implications, including transport through the blood-brain barrier.
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Affiliation(s)
- Edward J Calabrese
- Environmental Health Sciences Division, School of Public Health, University of Massachusetts, Amherst, Massachusetts 01003, USA.
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Nagaoka R, Iwasaki T, Rokutanda N, Takeshita A, Koibuchi Y, Horiguchi J, Shimokawa N, Iino Y, Morishita Y, Koibuchi N. Tamoxifen activates CYP3A4 and MDR1 genes through steroid and xenobiotic receptor in breast cancer cells. Endocrine 2006; 30:261-8. [PMID: 17526937 DOI: 10.1007/s12020-006-0003-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2006] [Revised: 10/31/2006] [Accepted: 11/27/2006] [Indexed: 10/23/2022]
Abstract
Cytochrome P450 monooxygenase 3A4 (CYP3A4) and P-glycoprotein, encoded by multidrug resistance 1 (MDR1) gene, are responsible for the metabolism of endogenous steroids, prescribed drugs, and xenobiotics. Both genes are regulated by steroid and xenobiotic receptor (SXR), a member of nuclear hormone receptors. Various endogenous steroids and drugs function as ligands of SXR. Although CYP3A4, MDR1, and SXR are expressed mainly in the liver and the small intestine, these gene products are also expressed in breast cancer cells. Because tamoxifen (TAM) is known to be metabolized by CYP3A4 and P-glycoprotein, we investigated the effect of TAM on these SXR-targeted genes in breast cancer cells. Transient transfection-based reporter gene assays showed 4-hydroxy TAM activated the SXR-mediated transcription through CYP3A4 and MDR1 promoters in a ligand- and receptor concentration-dependent manner. We confirmed the binding of 4-hydroxy TAM to SXR by ligand binding assay. Moreover, semiquantitative RT-PCR studies revealed that 4-hydroxy TAM activated the expression of CYP3A4 and MDR1 mRNA in MCF-7 cells. These results suggest that TAM induces CYP3A4 and MDR1 gene expression through SXR, which may affect TAM metabolic pathway in breast cancer cells.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism
- Adenocarcinoma/metabolism
- Antineoplastic Agents, Hormonal/metabolism
- Breast Neoplasms/metabolism
- Cell Line, Tumor
- Cytochrome P-450 CYP3A
- Cytochrome P-450 Enzyme System/genetics
- Cytochrome P-450 Enzyme System/metabolism
- Dose-Response Relationship, Drug
- Drug Resistance, Neoplasm/physiology
- Estrogen Antagonists/metabolism
- Gene Expression Regulation, Neoplastic
- Genes, MDR
- Humans
- Pregnane X Receptor
- RNA, Messenger/metabolism
- Receptors, Steroid/metabolism
- Receptors, Steroid/physiology
- Retinoid X Receptors/metabolism
- Tamoxifen/analogs & derivatives
- Tamoxifen/metabolism
- Transcription, Genetic
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Affiliation(s)
- Rin Nagaoka
- Department of Integrative Physiology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan
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Darvari R, Boroujerdi M. Investigation of the influence of modulation of P-glycoprotein by a multiple dosing regimen of tamoxifen on the pharmacokinetics and toxicodynamics of doxorubicin. Cancer Chemother Pharmacol 2005; 56:497-509. [PMID: 15937726 DOI: 10.1007/s00280-005-1001-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2004] [Accepted: 02/07/2005] [Indexed: 10/25/2022]
Abstract
PURPOSE The in vivo effect of modulators of P-glycoprotein (Pgp) on organ accumulation of substrates of Pgp has not been fully investigated. We investigated the influence of a Pgp modulator (tamoxifen, TAM) on the pharmacokinetics and toxicodynamics of a Pgp substrate (doxorubicin, DOX) in rats. METHODS TAM was administered daily for 11 days before the administration of DOX in male Sprague-Dawley rats, with all doses being clinically relevant. The experimental design of the project consisted of two different protocols. One was to investigate the effect of DOX on the time course of Pgp-ATPase activity, sarcoplasmic reticulum Ca(2+) -ATPase (SERCA) activity, and DOX concentration in the heart, liver, and kidneys of TAM-pretreated animals; the other protocol was to study the effect of TAM pretreatment on the disposition of DOX in the body by investigating its time course in plasma, urine and bile. RESULTS The simultaneous curve fitting of plasma data with urine and bile data with the help of the related pharmacokinetic equations provided the calculated parameters and constants. The first-order rate constants between the central and the myocardial compartments (k(1H) and k(H1)) were decreased in the TAM-treated group. The treatment also significantly reduced the k(1H)/k(H1) ratio in comparison to that of the control group. The first-order biliary elimination rate constant (k(b)) was significantly decreased (29%) in the TAM-treated group. The reduction was estimated in comparison with that of the control group. This reduction could be attributed to the inhibitory effect of TAM on Pgp located on biliary canicular membranes. The initial reduction of Pgp activity in TAM-treated group was at 60% of the basal level. The activity declined and reached a plateau at 20% of the basal activity after 6 h and remained at that level for 24 h. The area under the curves of Pgp-ATPase activity time (AUC(Activity 0-24)) following DOX administration in TAM-treated group was significantly lower than that of the control group, indicating an overall inhibitory effect of TAM on Pgp-ATPase activity under the protocol of this study. The area under the curves of the SERCA activity-time curve following DOX administration in TAM-treated group demonstrated a 15% reduction in AUC(Activity 0-24) in comparison with that of the control group, an indication of increased toxicity. The amount of myocardial Pgp in the 24-h period following DOX administration was comparable to the control group and showed no significant deviation from the basal levels of the protein. CONCLUSIONS The effect of TAM on DOX accumulation in the myocardial tissue and the increase in cardiotoxicity can be related to the net inhibitory effect of TAM on the efflux activity of Pgp in the heart. The results of the present study supported the hypothesis of the project that multiple regimen pretreatment with Pgp modulator TAM increases the DOX accumulation in the heart and promotes DOX-induced cardiotoxicity.
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Affiliation(s)
- Ramin Darvari
- Epic Therapeutics Inc., a Subsidiary of Baxter Healthcare Corporation, Norwood, MA 02062, USA
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