1
|
Persaud AK, Bernier MC, Massey MA, Agrawal S, Kaur T, Nayak D, Xie Z, Weadick B, Raj R, Hill K, Abbott N, Joshi A, Anabtawi N, Bryant C, Somogyi A, Cruz-Monserrate Z, Amari F, Coppola V, Sparreboom A, Baker SD, Unadkat JD, Phelps MA, Govindarajan R. Increased renal elimination of endogenous and synthetic pyrimidine nucleosides in concentrative nucleoside transporter 1 deficient mice. Nat Commun 2023; 14:3175. [PMID: 37264059 PMCID: PMC10235067 DOI: 10.1038/s41467-023-38789-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 05/16/2023] [Indexed: 06/03/2023] Open
Abstract
Concentrative nucleoside transporters (CNTs) are active nucleoside influx systems, but their in vivo roles are poorly defined. By generating CNT1 knockout (KO) mice, here we identify a role of CNT1 in the renal reabsorption of nucleosides. Deletion of CNT1 in mice increases the urinary excretion of endogenous pyrimidine nucleosides with compensatory alterations in purine nucleoside metabolism. In addition, CNT1 KO mice exhibits high urinary excretion of the nucleoside analog gemcitabine (dFdC), which results in poor tumor growth control in CNT1 KO mice harboring syngeneic pancreatic tumors. Interestingly, increasing the dFdC dose to attain an area under the concentration-time curve level equivalent to that achieved by wild-type (WT) mice rescues antitumor efficacy. The findings provide new insights into how CNT1 regulates reabsorption of endogenous and synthetic nucleosides in murine kidneys and suggest that the functional status of CNTs may account for the optimal action of pyrimidine nucleoside analog therapeutics in humans.
Collapse
Affiliation(s)
- Avinash K Persaud
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Matthew C Bernier
- Campus Chemical Instrument Center Mass Spectrometry and Proteomics Facility, The Ohio State University, Columbus, OH, 43210, USA
| | - Michael A Massey
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
- The Center for Life Sciences Education, College of Arts and Sciences, The Ohio State University, Columbus, OH, 43210, USA
| | - Shipra Agrawal
- Division of Nephrology & Hypertension, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY, 11794, USA
| | - Tejinder Kaur
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Debasis Nayak
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Zhiliang Xie
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Brenna Weadick
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Ruchika Raj
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Kasey Hill
- Pharmacoanalytic Shared Resource (PhASR), The Ohio State University, Columbus, OH, 43205, USA
| | - Nicole Abbott
- Pharmacoanalytic Shared Resource (PhASR), The Ohio State University, Columbus, OH, 43205, USA
| | - Arnav Joshi
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Nadeen Anabtawi
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Claire Bryant
- Center for Clinical & Translational Research, Nationwide Children's Hospital, Columbus, OH, 43210, USA
| | - Arpad Somogyi
- Campus Chemical Instrument Center Mass Spectrometry and Proteomics Facility, The Ohio State University, Columbus, OH, 43210, USA
| | - Zobeida Cruz-Monserrate
- Division of Gastroenterology, Hepatology, and Nutrition, College of Medicine, The Ohio State University, Columbus, OH, 43210, USA
| | - Foued Amari
- Genetically Engineered Mouse Modeling Core, Ohio State University Comprehensive Cancer Center, The Ohio State University, Columbus, OH, 43210, USA
| | - Vincenzo Coppola
- Genetically Engineered Mouse Modeling Core, Ohio State University Comprehensive Cancer Center, The Ohio State University, Columbus, OH, 43210, USA
- Department of Cancer Biology and Genetics, College of Medicine, The Ohio State University, Columbus, OH, 43210, USA
| | - Alex Sparreboom
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Sharyn D Baker
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Jashvant D Unadkat
- Department of Pharmaceutics, College of Pharmacy, University of Washington, Seattle, WA, 98195, USA
- Translational Therapeutics, Ohio State University Comprehensive Cancer Center, Ohio State University, Columbus, OH, 43210, USA
| | - Mitch A Phelps
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
- Pharmacoanalytic Shared Resource (PhASR), The Ohio State University, Columbus, OH, 43205, USA
| | - Rajgopal Govindarajan
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA.
- Translational Therapeutics, Ohio State University Comprehensive Cancer Center, Ohio State University, Columbus, OH, 43210, USA.
| |
Collapse
|
2
|
Yang M, Xu X. Important roles of transporters in the pharmacokinetics of anti-viral nucleoside/nucleotide analogs. Expert Opin Drug Metab Toxicol 2022; 18:483-505. [PMID: 35975669 PMCID: PMC9506706 DOI: 10.1080/17425255.2022.2112175] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 08/02/2022] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Nucleoside analogs are an important class of antiviral agents. Due to the high hydrophilicity and limited membrane permeability of antiviral nucleoside/nucleotide analogs (AVNAs), transporters play critical roles in AVNA pharmacokinetics. Understanding the properties of these transporters is important to accelerate translational research for AVNAs. AREAS COVERED The roles of key transporters in the pharmacokinetics of 25 approved AVNAs were reviewed. Clinically relevant information that can be explained by the modulation of transporter functions is also highlighted. EXPERT OPINION Although the roles of transporters in the intestinal absorption and renal excretion of AVNAs have been well identified, more research is warranted to understand their roles in the distribution of AVNAs, especially to immune privileged compartments where treatment of viral infection is challenging. P-gp, MRP4, BCRP, and nucleoside transporters have shown extensive impacts in the disposition of AVNAs. It is highly recommended that the role of transporters should be investigated during the development of novel AVNAs. Clinically, co-administered inhibitors and genetic polymorphism of transporters are the two most frequently reported factors altering AVNA pharmacokinetics. Physiopathology conditions also regulate transporter activities, while their effects on pharmacokinetics need further exploration. Pharmacokinetic models could be useful for elucidating these complicated factors in clinical settings.
Collapse
Affiliation(s)
- Mengbi Yang
- Drug Metabolism and Pharmacokinetics, Division of Preclinical Innovation (DPI), National Center for Advancing Translational Sciences (NCATS), National Institutes of Health, 9800 Medical Center Drive, Rockville, MD 20850, USA
| | - Xin Xu
- Drug Metabolism and Pharmacokinetics, Division of Preclinical Innovation (DPI), National Center for Advancing Translational Sciences (NCATS), National Institutes of Health, 9800 Medical Center Drive, Rockville, MD 20850, USA
| |
Collapse
|
3
|
Ali SS, Raj R, Kaur T, Weadick B, Nayak D, No M, Protos J, Odom H, Desai K, Persaud AK, Wang J, Govindarajan R. Solute Carrier Nucleoside Transporters in Hematopoiesis and Hematological Drug Toxicities: A Perspective. Cancers (Basel) 2022; 14:cancers14133113. [PMID: 35804885 PMCID: PMC9264962 DOI: 10.3390/cancers14133113] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 06/18/2022] [Accepted: 06/22/2022] [Indexed: 02/04/2023] Open
Abstract
Simple Summary Anticancer nucleoside analogs are promising treatments that often result in damaging toxicities and therefore ineffective treatment. Mechanisms of this are not well-researched, but cellular nucleoside transport research in mice might provide additional insight given transport’s role in mammalian hematopoiesis. Cellular nucleoside transport is a notable component of mammalian hematopoiesis due to how mutations within it relate to hematological abnormities. This review encompasses nucleoside transporters, focusing on their inherent properties, hematopoietic role, and their interplay in nucleoside drug treatment side effects. We then propose potential mechanisms to explain nucleoside transport involvement in blood disorders. Finally, we point out and advocate for future research areas that would improve therapeutic outcomes for patients taking nucleoside analog therapies. Abstract Anticancer nucleoside analogs produce adverse, and at times, dose-limiting hematological toxicities that can compromise treatment efficacy, yet the mechanisms of such toxicities are poorly understood. Recently, cellular nucleoside transport has been implicated in normal blood cell formation with studies from nucleoside transporter-deficient mice providing additional insights into the regulation of mammalian hematopoiesis. Furthermore, several idiopathic human genetic disorders have revealed nucleoside transport as an important component of mammalian hematopoiesis because mutations in individual nucleoside transporter genes are linked to various hematological abnormalities, including anemia. Here, we review recent developments in nucleoside transporters, including their transport characteristics, their role in the regulation of hematopoiesis, and their potential involvement in the occurrence of adverse hematological side effects due to nucleoside drug treatment. Furthermore, we discuss the putative mechanisms by which aberrant nucleoside transport may contribute to hematological abnormalities and identify the knowledge gaps where future research may positively impact treatment outcomes for patients undergoing various nucleoside analog therapies.
Collapse
Affiliation(s)
- Syed Saqib Ali
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA; (S.S.A.); (R.R.); (T.K.); (B.W.); (D.N.); (M.N.); (J.P.); (H.O.); (K.D.); (A.K.P.)
| | - Ruchika Raj
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA; (S.S.A.); (R.R.); (T.K.); (B.W.); (D.N.); (M.N.); (J.P.); (H.O.); (K.D.); (A.K.P.)
| | - Tejinder Kaur
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA; (S.S.A.); (R.R.); (T.K.); (B.W.); (D.N.); (M.N.); (J.P.); (H.O.); (K.D.); (A.K.P.)
| | - Brenna Weadick
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA; (S.S.A.); (R.R.); (T.K.); (B.W.); (D.N.); (M.N.); (J.P.); (H.O.); (K.D.); (A.K.P.)
| | - Debasis Nayak
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA; (S.S.A.); (R.R.); (T.K.); (B.W.); (D.N.); (M.N.); (J.P.); (H.O.); (K.D.); (A.K.P.)
| | - Minnsung No
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA; (S.S.A.); (R.R.); (T.K.); (B.W.); (D.N.); (M.N.); (J.P.); (H.O.); (K.D.); (A.K.P.)
| | - Jane Protos
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA; (S.S.A.); (R.R.); (T.K.); (B.W.); (D.N.); (M.N.); (J.P.); (H.O.); (K.D.); (A.K.P.)
| | - Hannah Odom
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA; (S.S.A.); (R.R.); (T.K.); (B.W.); (D.N.); (M.N.); (J.P.); (H.O.); (K.D.); (A.K.P.)
| | - Kajal Desai
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA; (S.S.A.); (R.R.); (T.K.); (B.W.); (D.N.); (M.N.); (J.P.); (H.O.); (K.D.); (A.K.P.)
| | - Avinash K. Persaud
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA; (S.S.A.); (R.R.); (T.K.); (B.W.); (D.N.); (M.N.); (J.P.); (H.O.); (K.D.); (A.K.P.)
| | - Joanne Wang
- Department of Pharmaceutics, College of Pharmacy, University of Washington, Seattle, WA 98195, USA;
| | - Rajgopal Govindarajan
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA; (S.S.A.); (R.R.); (T.K.); (B.W.); (D.N.); (M.N.); (J.P.); (H.O.); (K.D.); (A.K.P.)
- Translational Therapeutics, The Ohio State University Comprehensive Cancer Center, Columbus, OH 43210, USA
- Correspondence: ; Tel.: +1-614-247-8269; Fax: +1-614-292-2588
| |
Collapse
|
4
|
Markowicz-Piasecka M, Markiewicz A, Darłak P, Sikora J, Adla SK, Bagina S, Huttunen KM. Current Chemical, Biological, and Physiological Views in the Development of Successful Brain-Targeted Pharmaceutics. Neurotherapeutics 2022; 19:942-976. [PMID: 35391662 PMCID: PMC9294128 DOI: 10.1007/s13311-022-01228-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/24/2022] [Indexed: 12/13/2022] Open
Abstract
One of the greatest challenges with successful pharmaceutical treatments of central nervous system (CNS) diseases is the delivery of drugs into their target sites with appropriate concentrations. For example, the physically tight blood-brain barrier (BBB) effectively blocks compounds from penetrating into the brain, also by the action of metabolizing enzymes and efflux transport mechanisms. However, many endogenous compounds, including both smaller compounds and macromolecules, like amino acids, sugars, vitamins, nucleosides, hormones, steroids, and electrolytes, have their peculiar internalization routes across the BBB. These delivery mechanisms, namely carrier-mediated transport and receptor-mediated transcytosis have been utilized to some extent in brain-targeted drug development. The incomplete knowledge of the BBB and the smaller than a desirable number of chemical tools have hindered the development of successful brain-targeted pharmaceutics. This review discusses the recent advancements achieved in the field from the point of medicinal chemistry view and discusses how brain drug delivery can be improved in the future.
Collapse
Affiliation(s)
- Magdalena Markowicz-Piasecka
- Laboratory of Bioanalysis, Department of Pharmaceutical Chemistry, Drug Analysis and Radiopharmacy, Medical University of Lodz, ul. Muszyńskiego1, 90-151 Lodz, Poland
| | - Agata Markiewicz
- Students Research Group, Laboratory of Bioanalysis, Department of Pharmaceutical Chemistry, Drug Analysis and Radiopharmacy, Medical University of Lodz, ul. Muszyńskiego 1, 90-151 Lodz, Poland
| | - Patrycja Darłak
- Students Research Group, Laboratory of Bioanalysis, Department of Pharmaceutical Chemistry, Drug Analysis and Radiopharmacy, Medical University of Lodz, ul. Muszyńskiego 1, 90-151 Lodz, Poland
| | - Joanna Sikora
- Department of Bioinorganic Chemistry, Medical University of Lodz, Medical University of Lodz, ul. Muszyńskiego1, 90-151 Lodz, Poland
| | - Santosh Kumar Adla
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, Yliopistonranta 1C, POB 1627, 70211 Kuopio, Finland
- Institute of Organic Chemistry and Biochemistry (IOCB), Czech Academy of Sciences, Flemingovo Namesti 542/2, 160 00 Prague, Czech Republic
| | - Sreelatha Bagina
- Charles River Discovery Research Services Finland Oy, Neulaniementie 4, 70210 Kuopio, Finland
| | - Kristiina M. Huttunen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, Yliopistonranta 1C, POB 1627, 70211 Kuopio, Finland
| |
Collapse
|
5
|
Hodel EM, Marzolini C, Waitt C, Rakhmanina N. Pharmacokinetics, Placental and Breast Milk Transfer of Antiretroviral Drugs in Pregnant and Lactating Women Living with HIV. Curr Pharm Des 2020; 25:556-576. [PMID: 30894103 DOI: 10.2174/1381612825666190320162507] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 03/18/2019] [Indexed: 12/22/2022]
Abstract
BACKGROUND Remarkable progress has been achieved in the identification of HIV infection in pregnant women and in the prevention of vertical HIV transmission through maternal antiretroviral treatment (ART) and neonatal antiretroviral drug (ARV) prophylaxis in the last two decades. Millions of women globally are receiving combination ART throughout pregnancy and breastfeeding, periods associated with significant biological and physiological changes affecting the pharmacokinetics (PK) and pharmacodynamics (PD) of ARVs. The objective of this review was to summarize currently available knowledge on the PK of ARVs during pregnancy and transport of maternal ARVs through the placenta and into the breast milk. We also summarized main safety considerations for in utero and breast milk ARVs exposures in infants. METHODS We conducted a review of the pharmacological profiles of ARVs in pregnancy and during breastfeeding obtained from published clinical studies. Selected maternal PK studies used a relatively rich sampling approach at each ante- and postnatal sampling time point. For placental and breast milk transport of ARVs, we selected the studies that provided ratios of maternal to the cord (M:C) plasma and breast milk to maternal plasma (M:P) concentrations, respectively. RESULTS We provide an overview of the physiological changes during pregnancy and their effect on the PK parameters of ARVs by drug class in pregnancy, which were gathered from 45 published studies. The PK changes during pregnancy affect the dosing of several protease inhibitors during pregnancy and limit the use of several ARVs, including three single tablet regimens with integrase inhibitors or protease inhibitors co-formulated with cobicistat due to suboptimal exposures. We further analysed the currently available data on the mechanism of the transport of ARVs from maternal plasma across the placenta and into the breast milk and summarized the effect of pregnancy on placental and of breastfeeding on mammal gland drug transporters, as well as physicochemical properties, C:M and M:P ratios of individual ARVs by drug class. Finally, we discussed the major safety issues of fetal and infant exposure to maternal ARVs. CONCLUSIONS Available pharmacological data provide evidence that physiological changes during pregnancy affect maternal, and consequently, fetal ARV exposure. Limited available data suggest that the expression of drug transporters may vary throughout pregnancy and breastfeeding thereby possibly impacting the amount of ARV crossing the placenta and secreted into the breast milk. The drug transporter's role in the fetal/child exposure to maternal ARVs needs to be better understood. Our analysis underscores the need for more pharmacological studies with innovative study design, sparse PK sampling, improved study data reporting and PK modelling in pregnant and breastfeeding women living with HIV to optimize their treatment choices and maternal and child health outcomes.
Collapse
Affiliation(s)
- E M Hodel
- Department of Molecular and Clinical Pharmacology, University of Liverpool, Molecular & Clinical Pharmacology, Liverpool, United Kingdom.,Liverpool School of Tropical Medicine, Liverpool, United Kingdom.,Division of Paediatric Pharmacology & Pharmacometrics, University of Basel Children's Hospital, Basel, Switzerland
| | - C Marzolini
- Department of Molecular and Clinical Pharmacology, University of Liverpool, Molecular & Clinical Pharmacology, Liverpool, United Kingdom.,Division of Infectious Diseases and Hospital Epidemiology, University Hospital of Basel, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - C Waitt
- Department of Molecular and Clinical Pharmacology, University of Liverpool, Molecular & Clinical Pharmacology, Liverpool, United Kingdom.,Infectious Diseases Institute, Makerere University College of Health Sciences, Kampala, Uganda.,Royal Liverpool University Hospital, Liverpool, United Kingdom
| | - N Rakhmanina
- Department of Pediatrics, The George Washington University, School of Medicine & Health Sciences, Washington, DC, United States.,Division of Infectious Diseases, Children's National Medical Center, Washington, DC, United States.,Elizabeth Glaser Pediatric AIDS Foundation, Washington, DC, United States
| |
Collapse
|
6
|
Xie CY, Wang Q, Li G, Fan Z, Wang H, Wu X. Dietary supplement with nucleotides in the form of uridine monophosphate or uridine stimulate intestinal development and promote nucleotide transport in weaned piglets. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2019; 99:6108-6113. [PMID: 31177538 DOI: 10.1002/jsfa.9850] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 06/04/2019] [Accepted: 06/05/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND Nucleotides are key constituents of milk, where they are utilized in cell replication, although there are limited studies for weaned piglets. This study evaluated the effects of uridine monophosphate (UMP) with uridine (UR) feed supplementation on the intestinal development and nucleotide transport in weaned piglets. RESULTS Supplementation with UMP significantly increased (P < 0.05) plasma glucose, and UR supplementation significantly reduced (0.05 < P < 0.10) the plasma total cholesterol (TC) of piglets when compared with that of the control group, although non-significant difference (P > 0.05) in growth performance was observed among three groups. Piglets fed supplementary UR exhibited greater (P < 0.05) crypt depth in the duodenum and ileum when compared with those in the supplementary UMP and control groups. Real-time quantitative polymerase chain reaction (RT-qPCR) results revealed that UR supplementation increased (P < 0.05) the relative mRNA levels of genes encoding the transmembrane proteins ZO-1 and occludin in the duodenum mucosa, and ZO-1 in the jejunum mucosa (P < 0.05). Similarly, UR supplementation increased (P < 0.05) expression of solute carriers SLC28A1 and SLC29A1 in the duodenum mucosa. Conversely, claudin-1 expression in the duodenum mucosa was inhibited (P < 0.05) by dietary supplementation with UMP or UR. CONCLUSION Collectively, our data indicated that dietary supplementation with UMP or UR was conducive to stimulating intestinal development and promoting nucleotide transport in weaned piglets. © 2019 Society of Chemical Industry.
Collapse
Affiliation(s)
- Chun-Yan Xie
- College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, China
| | - Qinhua Wang
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences; National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production, Changsha, China
- Hunan Co-Innovation Center of Safety Animal Production, College of Animal Science and Technology, Hunan Agricultural University, Changsha, China
| | - Guanya Li
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences; National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production, Changsha, China
- Hunan Co-Innovation Center of Safety Animal Production, College of Animal Science and Technology, Hunan Agricultural University, Changsha, China
| | - Zhiyong Fan
- Hunan Co-Innovation Center of Safety Animal Production, College of Animal Science and Technology, Hunan Agricultural University, Changsha, China
| | - Hong Wang
- Meiya Hai'an Pharmaceutical Co., Ltd, Hai'an, China
| | - Xin Wu
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences; National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production, Changsha, China
| |
Collapse
|
7
|
Pastor-Anglada M, Urtasun N, Pérez-Torras S. Intestinal Nucleoside Transporters: Function, Expression, and Regulation. Compr Physiol 2018; 8:1003-1017. [PMID: 29978890 DOI: 10.1002/cphy.c170039] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The gastrointestinal tract is the absorptive organ for nutrients found in foods after digestion. Nucleosides and, to a lesser extent nucleobases, are the late products of nucleoprotein digestion. These metabolites are absorbed by nucleoside (and nucleobase) transporter (NT) proteins. NTs are differentially distributed along the gastrointestinal tract showing also polarized expression in epithelial cells. Concentrative nucleoside transporters (CNTs) are mainly located at the apical side of enterocytes, whereas equilibrative nucleoside transporters (ENTs) facilitate the basolateral efflux of nucleosides and nucleobases to the bloodstream. Moreover, selected nucleotides and the bioactive nucleoside adenosine act directly on intestinal cells modulating purinergic signaling. NT-polarized insertion is tightly regulated. However, not much is known about the modulation of intestinal NT function in humans, probably due to the lack of appropriate cell models retaining CNT functional expression. Thus, the possibility of nutritional regulation of intestinal NTs has been addressed using animal models. Besides the nutrition-related role of NT proteins, orally administered drugs also need to cross the intestinal barrier, this event being a major determinant of drug bioavailability. In this regard, NT proteins might also play a role in pharmacology, thereby allowing the absorption of nucleoside- and nucleobase-derived drugs. The relative broad selectivity of these membrane transporters also suggests clinically relevant drug-drug interactions when using combined therapies. This review focuses on all these physiological and pharmacological aspects of NT protein biology. © 2017 American Physiological Society. Compr Physiol 8:1003-1017, 2018.
Collapse
Affiliation(s)
- Marçal Pastor-Anglada
- Biochemistry and Molecular Pharmacology Section, Department of Biochemistry and Molecular Biomedicine, Institute of Biomedicine (IBUB), University of Barcelona, Barcelona, Spain.,Oncology Program, National Biomedical Research Institute on Liver and Gastrointestinal Diseases (CIBER EHD), Instituto de Salud Carlos III, Barcelona, Spain.,Genetics, Molecular Biology and Gene Therapy Program, Institut de Recerca Sant Joan de Déu (IR SJD), Esplugues de Llobregat, Barcelona, Spain
| | - Nerea Urtasun
- Biochemistry and Molecular Pharmacology Section, Department of Biochemistry and Molecular Biomedicine, Institute of Biomedicine (IBUB), University of Barcelona, Barcelona, Spain.,Oncology Program, National Biomedical Research Institute on Liver and Gastrointestinal Diseases (CIBER EHD), Instituto de Salud Carlos III, Barcelona, Spain.,Genetics, Molecular Biology and Gene Therapy Program, Institut de Recerca Sant Joan de Déu (IR SJD), Esplugues de Llobregat, Barcelona, Spain
| | - Sandra Pérez-Torras
- Biochemistry and Molecular Pharmacology Section, Department of Biochemistry and Molecular Biomedicine, Institute of Biomedicine (IBUB), University of Barcelona, Barcelona, Spain.,Oncology Program, National Biomedical Research Institute on Liver and Gastrointestinal Diseases (CIBER EHD), Instituto de Salud Carlos III, Barcelona, Spain.,Genetics, Molecular Biology and Gene Therapy Program, Institut de Recerca Sant Joan de Déu (IR SJD), Esplugues de Llobregat, Barcelona, Spain
| |
Collapse
|
8
|
Calcagno A, Cusato J, D'Avolio A, Bonora S. Genetic Polymorphisms Affecting the Pharmacokinetics of Antiretroviral Drugs. Clin Pharmacokinet 2017; 56:355-369. [PMID: 27641153 DOI: 10.1007/s40262-016-0456-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Antiretroviral treatment is highly effective in enhancing HIV-positive patients' survival and quality of life. Despite an increased tolerability in recent years, a substantial amount of patients experience side effects. Antiretrovirals' efficacy and tolerability have been associated with plasma concentrations and single nucleotide polymorphisms in selected genes involved in drug disposition. OBJECTIVE Our aim was to review the current knowledge in genetic polymorphisms affecting plasma, intracellular or compartmental concentrations of antiretrovirals. METHODS A search of the PubMed database was conducted to identify relevant articles, using the following terms: 'pharmacogenetics' or 'pharmacogenomics' or 'single nucleotide polymorphisms' or 'genetic/allelic variants' and 'pharmacokinetics' or 'concentrations' and 'HIV' or 'antiretroviral'. Abstracts from the main HIV conferences during 2015 and 2016 were also searched using the same keywords. Abstracts were manually checked and, if relevant, full papers were obtained. Only articles published in English were selected. RESULTS Several genetic polymorphisms in genes coding enzymes involved in drug metabolism (cytochrome P450 isoenzymes and uridine diphosphate glucuronosyltransferases) and transport (P-glycoprotein, anionic and cationic transporters, other transporters), as well as nuclear receptors (pregnane X receptor and the constitutive androstane receptor), have been associated with concentrations of antiretrovirals. The extent of such influence, the conflicting data, and the potential clinical relevance are discussed in the main section of this article. CONCLUSION Genetic polymorphisms may affect antiretroviral disposition, as well as both efficacy and toxicity. Despite a large amount of data, such precious knowledge has seldom been applied in patients. Studies on the clinical relevance and cost effectiveness of tailoring antiretroviral regimens to patients' genetic assets are lacking, but their importance may grow with the increasing age and complexity of persons living with HIV/AIDS.
Collapse
Affiliation(s)
- Andrea Calcagno
- Unit of Infectious Diseases, Department of Medical Sciences, University of Torino, c/o Ospedale Amedeo di Savoia, C.so Svizzera 164, 10159, Torino, Italy.
| | - Jessica Cusato
- Unit of Infectious Diseases, Department of Medical Sciences, University of Torino, c/o Ospedale Amedeo di Savoia, C.so Svizzera 164, 10159, Torino, Italy
| | - Antonio D'Avolio
- Unit of Infectious Diseases, Department of Medical Sciences, University of Torino, c/o Ospedale Amedeo di Savoia, C.so Svizzera 164, 10159, Torino, Italy
| | - Stefano Bonora
- Unit of Infectious Diseases, Department of Medical Sciences, University of Torino, c/o Ospedale Amedeo di Savoia, C.so Svizzera 164, 10159, Torino, Italy
| |
Collapse
|
9
|
Role of ABC and Solute Carrier Transporters in the Placental Transport of Lamivudine. Antimicrob Agents Chemother 2016; 60:5563-72. [PMID: 27401571 DOI: 10.1128/aac.00648-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 07/03/2016] [Indexed: 12/26/2022] Open
Abstract
Lamivudine is one of the antiretroviral drugs of choice for the prevention of mother-to-child transmission (MTCT) in HIV-positive women. In this study, we investigated the relevance of drug efflux transporters P-glycoprotein (P-gp) (MDR1 [ABCB1]), BCRP (ABCG2), MRP2 (ABCC2), and MATE1 (SLC47A1) for the transmembrane transport and transplacental transfer of lamivudine. We employed in vitro accumulation and transport experiments on MDCK cells overexpressing drug efflux transporters, in situ-perfused rat term placenta, and vesicular uptake in microvillous plasma membrane (MVM) vesicles isolated from human term placenta. MATE1 significantly accelerated lamivudine transport in MATE1-expressing MDCK cells, whereas no transporter-driven efflux of lamivudine was observed in MDCK-MDR1, MDCK-MRP2, and MDCK-BCRP monolayers. MATE1-mediated efflux of lamivudine appeared to be a low-affinity process (apparent Km of 4.21 mM and Vmax of 5.18 nmol/mg protein/min in MDCK-MATE1 cells). Consistent with in vitro transport studies, the transplacental clearance of lamivudine was not affected by P-gp, BCRP, or MRP2. However, lamivudine transfer across dually perfused rat placenta and the uptake of lamivudine into human placental MVM vesicles revealed pH dependency, indicating possible involvement of MATE1 in the fetal-to-maternal efflux of the drug. To conclude, placental transport of lamivudine does not seem to be affected by P-gp, MRP2, or BCRP, but a pH-dependent mechanism mediates transport of lamivudine in the fetal-to-maternal direction. We suggest that MATE1 might be, at least partly, responsible for this transport.
Collapse
|
10
|
Alam C, Whyte-Allman SK, Omeragic A, Bendayan R. Role and modulation of drug transporters in HIV-1 therapy. Adv Drug Deliv Rev 2016; 103:121-143. [PMID: 27181050 DOI: 10.1016/j.addr.2016.05.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 04/29/2016] [Accepted: 05/03/2016] [Indexed: 12/15/2022]
Abstract
Current treatment of human immunodeficiency virus type-1 (HIV-1) infection involves a combination of antiretroviral drugs (ARVs) that target different stages of the HIV-1 life cycle. This strategy is commonly referred to as highly active antiretroviral therapy (HAART) or combined antiretroviral therapy (cART). Membrane-associated drug transporters expressed ubiquitously in mammalian systems play a crucial role in modulating ARV disposition during HIV-1 infection. Members of the ATP-binding cassette (ABC) and solute carrier (SLC) transporter superfamilies have been shown to interact with ARVs, including those that are used as part of first-line treatment regimens. As a result, the functional expression of drug transporters can influence the distribution of ARVs at specific sites of infection. In addition, pathological factors related to HIV-1 infection and/or ARV therapy itself can alter transporter expression and activity, thus further contributing to changes in ARV disposition and the effectiveness of HAART. This review summarizes current knowledge on the role of drug transporters in regulating ARV transport in the context of HIV-1 infection.
Collapse
Affiliation(s)
- Camille Alam
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Toronto, Ontario M5S 2S2, Canada
| | - Sana-Kay Whyte-Allman
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Toronto, Ontario M5S 2S2, Canada
| | - Amila Omeragic
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Toronto, Ontario M5S 2S2, Canada
| | - Reina Bendayan
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Toronto, Ontario M5S 2S2, Canada.
| |
Collapse
|
11
|
Hu M, Patel SK, Zhou T, Rohan LC. Drug transporters in tissues and cells relevant to sexual transmission of HIV: Implications for drug delivery. J Control Release 2015; 219:681-696. [PMID: 26278511 PMCID: PMC4656065 DOI: 10.1016/j.jconrel.2015.08.018] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2015] [Revised: 08/05/2015] [Accepted: 08/06/2015] [Indexed: 01/11/2023]
Abstract
Efflux and uptake transporters of drugs are key regulators of the pharmacokinetics of many antiretroviral drugs. A growing body of literature has revealed the expression and functionality of multiple transporters in female genital tract (FGT), colorectal tissue, and immune cells. Drug transporters could play a significant role in the efficacy of preventative strategies for HIV-1 acquisition. Pre-exposure prophylaxis (PrEP) is a promising strategy, which utilizes topically (vaginally or rectally), orally or other systemically administered antiretroviral drugs to prevent the sexual transmission of HIV to receptive partners. The drug concentration in the receptive mucosal tissues and target immune cells for HIV is critical for PrEP effectiveness. Hence, there is an emerging interest in utilizing transporter information to explain tissue disposition patterns of PrEP drugs, to interpret inter-individual variability in PrEP drug pharmacokinetics and effectiveness, and to improve tissue drug exposure through modulation of the cervicovaginal, colorectal, or immune cell transporters. In this review, the existing literature on transporter expression, functionality and regulation in the transmission-related tissues and cells is summarized. In addition, the relevance of transporter function for drug delivery and strategies that could exploit transporters for increased drug concentration at target locales is discussed. The overall goal is to facilitate an understanding of drug transporters for PrEP optimization.
Collapse
Affiliation(s)
- Minlu Hu
- School of Pharmacy, University of Pittsburgh, Pittsburgh, PA, USA; Magee-Womens Research Institute, Pittsburgh, PA, USA
| | - Sravan Kumar Patel
- School of Pharmacy, University of Pittsburgh, Pittsburgh, PA, USA; Magee-Womens Research Institute, Pittsburgh, PA, USA
| | - Tian Zhou
- School of Pharmacy, University of Pittsburgh, Pittsburgh, PA, USA; Magee-Womens Research Institute, Pittsburgh, PA, USA
| | - Lisa C Rohan
- School of Pharmacy, University of Pittsburgh, Pittsburgh, PA, USA; Magee-Womens Research Institute, Pittsburgh, PA, USA; School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.
| |
Collapse
|
12
|
Pastor-Anglada M, Pérez-Torras S. Nucleoside transporter proteins as biomarkers of drug responsiveness and drug targets. Front Pharmacol 2015; 6:13. [PMID: 25713533 PMCID: PMC4322540 DOI: 10.3389/fphar.2015.00013] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Accepted: 01/13/2015] [Indexed: 12/13/2022] Open
Abstract
Nucleoside and nucleobase analogs are currently used in the treatment of solid tumors, lymphoproliferative diseases, viral infections such as hepatitis and AIDS, and some inflammatory diseases such as Crohn. Two gene families are implicated in the uptake of nucleosides and nucleoside analogs into cells, SCL28 and SLC29. The former encodes hCNT1, hCNT2, and hCNT3 proteins. They translocate nucleosides in a Na+ coupled manner with high affinity and some substrate selectivity, being hCNT1 and hCNT2 pyrimidine- and purine-preferring, respectively, and hCNT3 a broad selectivity transporter. SLC29 genes encode four members, being hENT1 and hENT2 the only two which are unequivocally implicated in the translocation of nucleosides and nucleobases (the latter mostly via hENT2) at the cell plasma membrane. Some nucleoside-derived drugs can also interact with and be translocated by members of the SLC22 gene family, particularly hOCT and hOAT proteins. Inter-individual differences in transporter function and perhaps, more importantly, altered expression associated with the disease itself might modulate the transporter profile of target cells, thereby determining drug bioavailability and action. Drug transporter pharmacology has been periodically reviewed. Thus, with this contribution we aim at providing a state-of-the-art overview of the clinical evidence generated so far supporting the concept that these membrane proteins can indeed be biomarkers suitable for diagnosis and/or prognosis. Last but not least, some of these transporter proteins can also be envisaged as drug targets, as long as they can show “transceptor” functions, in some cases related to their role as modulators of extracellular adenosine levels, thereby providing a functional link between P1 receptors and transporters.
Collapse
Affiliation(s)
- Marçal Pastor-Anglada
- Molecular Pharmacology and Experimental Therapeutics, Department of Biochemistry and Molecular Biology, Institute of Biomedicine, University of Barcelona, Barcelona Spain ; Oncology Program, CIBER ehd, National Biomedical Research Institute on Liver and Gastrointestinal Diseases, Instituto de Salud Carlos III, Barcelona Spain
| | - Sandra Pérez-Torras
- Molecular Pharmacology and Experimental Therapeutics, Department of Biochemistry and Molecular Biology, Institute of Biomedicine, University of Barcelona, Barcelona Spain ; Oncology Program, CIBER ehd, National Biomedical Research Institute on Liver and Gastrointestinal Diseases, Instituto de Salud Carlos III, Barcelona Spain
| |
Collapse
|
13
|
Chishu T, Sai Y, Nishimura T, Sato K, Kose N, Nakashima E. Potential of various drugs to inhibit nucleoside uptake in rat syncytiotrophoblast cell line, TR-TBT 18d-1. Placenta 2008; 29:461-7. [PMID: 18329095 DOI: 10.1016/j.placenta.2008.01.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2007] [Revised: 01/17/2008] [Accepted: 01/22/2008] [Indexed: 10/22/2022]
Abstract
The placenta requires nucleosides as nutrients for fetal growth, so it is important to examine potential interactions between placental transports of nucleosides and drugs to ensure the safety of pharmacotherapy during pregnancy. The purposes of this study are to clarify the uptake mechanisms of nucleosides from the maternal side of the syncytiotrophoblast and to investigate the inhibitory effect of various drugs on nucleoside uptake, using the rat syncytiotrophoblast cell line TR-TBT 18d-1, which shows syncytial-like morphology and functional expression of several transporters. Initial uptake of [(3)H]uridine or [(3)H]adenosine from the apical side of TR-TBT 18d-1 was markedly reduced by an excess of the respective unlabelled compound, and was slightly reduced by replacement of Na(+) with N-methyl-d-glucamine, indicating that both uptakes were Na(+)-independent. [(3)H]Uridine and [(3)H]adenosine uptakes in the absence of Na(+) were significantly and concentration-dependently inhibited by both 0.1 microM and 100 microM nitrobenzylthioinosine, suggesting the involvement of equilibrative nucleoside transporters (ENTs, SLC29). Kinetic analysis of adenosine uptake yielded a K(m) value of approximately 17 microM. These results are consistent with the reported uptake characteristics of uridine and adenosine by ENT1 and ENT2. The uptakes were significantly reduced by high concentrations of several nucleoside drugs, including cytarabine, vidarabine, zidovudine, mizoribine, caffeine and amitriptyline, but the effects were small within the therapeutic concentration ranges. In summary, our results suggest that ENTs are involved in apical uptake of uridine and adenosine in the syncytiotrophoblast. However, therapeutic concentrations of the drugs tested in this study might have little influence on maternal-to-fetal nucleoside transfer.
Collapse
Affiliation(s)
- T Chishu
- Department of Pharmaceutics, Kyoritsu University of Pharmacy, 1-5-30 Shiba-koen, Minato-ku, Tokyo 105-8512, Japan
| | | | | | | | | | | |
Collapse
|
14
|
Altered Expression of Nucleoside Transporter Genes (SLC28 and SLC29) in Adipose Tissue from HIV-1–Infected Patients. Antivir Ther 2007. [DOI: 10.1177/135965350701200601] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Background Nucleoside transporter proteins (NTs) encoded by members of the SLC28 and SLC29 gene families contribute to nucleoside and nucleobase recycling but also modulate extracellular adenosine levels and thus adenosine-regulated metabolic targets. Methods We have examined the expression pattern of NT-encoding genes in human adipose tissue and we have further analysed whether the mRNA related to these genes show changes in their amounts associated with either HIV-1 infection, highly active antiretroviral therapy (HAART) or development of HIV-1-associated lipodystrophy syndrome (HALS). Results Human adipocytes express SLC28A1, SLC28A2 and SLC28A3 (encoding hCNT1, hCNT2 and hCNT3, respectively) and SLC29A1 and SLC29A2 (encoding hENT1 and hENT2, respectively). HIV-1 infection, prior to HAART and HALS development, is associated with the upregulation of the mRNA levels of the genes encoding hCNT1, hCNT3 and hENT2. The increase in the mRNA amounts for the former two genes may be due to the action of tumour necrosis factor-α (TNF-α), a cytokine with enhanced expression in adipose tissue following HIV-1 infection, as the effect is also observed in human adipocytes in culture after treatment with TNF-α. HAART and HALS development are associated with the upregulation of the mRNA levels encoding hCNT2 and hENT1, and further enhancement of hCNT1, hCNT3 and hENT2 gene expression. Conclusions These data suggest that selected genes of the SLC28 and SLC29 families are not only targets of HIV-1 infection, but might also contribute to the development of adipose tissue alterations leading to lipodystrophy.
Collapse
|
15
|
Purcet S, Minuesa G, Molina-Arcas M, Erkizia I, Casado FJ, Clotet B, Martínez-Picado J, Pastor-Anglada M. 3′-Azido-2′,3′-Dideoxythymidine (Zidovudine) Uptake Mechanisms in T Lymphocytes. Antivir Ther 2006. [DOI: 10.1177/135965350601100603] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The nucleoside reverse transcriptase inhibitors (NRTIs) make up a family of antiretroviral drugs widely used in the treatment of HIV-1 infection. Human concentrative nucleoside transporters and equilibrative nucleoside transporters, encoded by SLC28 and SLC29 gene families, respectively, are known to be involved in the uptake of a variety of nucleoside analogues used in anticancer treatment. We therefore examined whether SLC28- and SLC29-encoded proteins contribute to the entry of these NRTIs into the human leukaemic T-cell line Molt-4. Cis-inhibition experiments demonstrated that nucleoside transporters have a negligible role in antiviral drug uptake. Moreover, the previously identified 3′-azido-2′,3′-dideoxythymidine (zidovudine; AZT) carriers, organic anion transporters (organic anion transporter [hOATs], members of the SLC22 gene family) have not been detected in T cells, either functionally or at the mRNA level, thus ruling out a role for hOATs in antiviral drug uptake in these cells. Nevertheless, the data provided here argue against the hypothesis of simple diffusion across the plasma membrane as the unique mechanism of AZT uptake. Actually, this pyrimidine derivative seems to have a temperature-sensitive route of entrance, a finding that, along with the evidence that, AZT inhibits its own uptake and its transport into phytohaemagglutinin-stimulated peripheral blood mononuclear cells is upregulated, strongly support the idea that AZT uptake into T-cells is associated with a mediated and regulated, transport mechanism.
Collapse
Affiliation(s)
- Sergi Purcet
- Regulació dels Sistemes de Transport (RST), Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
| | - Gerard Minuesa
- IrsiCaixa Foundation, Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, Badalona, Spain
| | - Míriam Molina-Arcas
- Regulació dels Sistemes de Transport (RST), Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
| | - Itziar Erkizia
- IrsiCaixa Foundation, Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, Badalona, Spain
| | - F Javier Casado
- Regulació dels Sistemes de Transport (RST), Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
| | - Bonaventura Clotet
- IrsiCaixa Foundation, Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, Badalona, Spain
| | - Javier Martínez-Picado
- IrsiCaixa Foundation, Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, Badalona, Spain
| | - Marçal Pastor-Anglada
- Regulació dels Sistemes de Transport (RST), Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
| |
Collapse
|