1
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Badaut J, Blochet C, Obenaus A, Hirt L. Physiological and pathological roles of caveolins in the central nervous system. Trends Neurosci 2024:S0166-2236(24)00117-6. [PMID: 38972795 DOI: 10.1016/j.tins.2024.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 05/14/2024] [Accepted: 06/12/2024] [Indexed: 07/09/2024]
Abstract
Caveolins are a family of transmembrane proteins located in caveolae, small lipid raft invaginations of the plasma membrane. The roles of caveolin-enriched lipid rafts are diverse, and include mechano-protection, lipid homeostasis, metabolism, transport, and cell signaling. Caveolin-1 (Cav-1) and other caveolins were described in endothelial cells and later in other cell types of the central nervous system (CNS), including neurons, astrocytes, oligodendrocytes, microglia, and pericytes. This pancellular presence of caveolins demands a better understanding of their functional roles in each cell type. In this review we describe the various functions of Cav-1 in the cells of normal and pathological brains. Several emerging preclinical findings suggest that Cav-1 could represent a potential therapeutic target in brain disorders.
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Affiliation(s)
- Jérôme Badaut
- CNRS UMR 5536 RMSB-University of Bordeaux, Bordeaux, France; Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA, USA.
| | - Camille Blochet
- Department of Clinical Neurosciences, CHUV, Lausanne, Switzerland; Department of Fundamental Neuroscience, University of Lausanne, Lausanne, Switzerland
| | - André Obenaus
- Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA, USA; Division of Biomedical Sciences, University of California Riverside, Riverside, CA, USA
| | - Lorenz Hirt
- Department of Clinical Neurosciences, CHUV, Lausanne, Switzerland; Department of Fundamental Neuroscience, University of Lausanne, Lausanne, Switzerland
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2
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Lin MC, Kuo WH, Chen SY, Hsu JY, Lu LY, Wang CC, Chen YJ, Tsai JS, Li HJ. Ago2/CAV1 interaction potentiates metastasis via controlling Ago2 localization and miRNA action. EMBO Rep 2024; 25:2441-2478. [PMID: 38649663 PMCID: PMC11094075 DOI: 10.1038/s44319-024-00132-7] [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: 11/07/2023] [Revised: 03/22/2024] [Accepted: 03/27/2024] [Indexed: 04/25/2024] Open
Abstract
Ago2 differentially regulates oncogenic and tumor-suppressive miRNAs in cancer cells. This discrepancy suggests a secondary event regulating Ago2/miRNA action in a context-dependent manner. We show here that a positive charge of Ago2 K212, that is preserved by SIR2-mediated Ago2 deacetylation in cancer cells, is responsible for the direct interaction between Ago2 and Caveolin-1 (CAV1). Through this interaction, CAV1 sequesters Ago2 on the plasma membranes and regulates miRNA-mediated translational repression in a compartment-dependent manner. Ago2/CAV1 interaction plays a role in miRNA-mediated mRNA suppression and in miRNA release via extracellular vesicles (EVs) from tumors into the circulation, which can be used as a biomarker of tumor progression. Increased Ago2/CAV1 interaction with tumor progression promotes aggressive cancer behaviors, including metastasis. Ago2/CAV1 interaction acts as a secondary event in miRNA-mediated suppression and increases the complexity of miRNA actions in cancer.
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Affiliation(s)
- Meng-Chieh Lin
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli, 35053, Taiwan
| | - Wen-Hung Kuo
- Department of Surgery, National Taiwan University Hospital, Taipei, 100229, Taiwan
| | - Shih-Yin Chen
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli, 35053, Taiwan
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Jing-Ya Hsu
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli, 35053, Taiwan
| | - Li-Yu Lu
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli, 35053, Taiwan
| | - Chen-Chi Wang
- Department of Surgery, National Taiwan University Hospital, Taipei, 100229, Taiwan
| | - Yi-Ju Chen
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli, 35053, Taiwan
| | - Jia-Shiuan Tsai
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli, 35053, Taiwan
| | - Hua-Jung Li
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli, 35053, Taiwan.
- Program in Tissue Engineering and Regenerative Medicine, National Chung Hsing University, Taichung City, 402, Taiwan.
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3
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Ni C, Hong M. Oligomerization of drug transporters: Forms, functions, and mechanisms. Acta Pharm Sin B 2024; 14:1924-1938. [PMID: 38799641 PMCID: PMC11119549 DOI: 10.1016/j.apsb.2024.01.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 12/07/2023] [Accepted: 01/05/2024] [Indexed: 05/29/2024] Open
Abstract
Drug transporters are essential players in the transmembrane transport of a wide variety of clinical drugs. The broad substrate spectra and versatile distribution pattern of these membrane proteins infer their pharmacological and clinical significance. With our accumulating knowledge on the three-dimensional structure of drug transporters, their oligomerization status has become a topic of intense study due to the possible functional roles carried out by such kind of post-translational modification (PTM). In-depth studies of oligomeric complexes formed among drug transporters as well as their interactions with other regulatory proteins can help us better understand the regulatory mechanisms of these membrane proteins, provide clues for the development of novel drugs, and improve the therapeutic efficacy. In this review, we describe different oligomerization forms as well as their structural basis of major drug transporters in the ATP-binding cassette and solute carrier superfamilies, summarize our current knowledge on the influence of oligomerization for protein expression level and transport function of these membrane proteins, and discuss the regulatory mechanisms of oligomerization. Finally, we highlight the challenges associated with the current oligomerization studies and propose some thoughts on the pharmaceutical application of this important drug transporter PTM.
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Affiliation(s)
- Chunxu Ni
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Mei Hong
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, South China Agricultural University, Guangzhou 510642, China
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4
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Xie YY, Lu YW, Yu GR. The protective effects of hyperoside on Ang II-mediated apoptosis of bEnd.3 cells and injury of blood-brain barrier model in vitro. BMC Complement Med Ther 2022; 22:157. [PMID: 35698113 PMCID: PMC9195266 DOI: 10.1186/s12906-022-03635-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 05/30/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Hypertension and its associated dysfunction of the blood-brain barrier (BBB) are considered to contribute to cerebral small vessel disease (cSVD). Angiotensin II (Ang II), as an important vasoactive peptide of the renin-angiotensin system (RAS), is not only a pivotal molecular signal in hypertension, but also causes BBB leakage, cSVD and its related cognitive impair. Hyperoside (Hyp), a flavone glycoside, has antioxidant, antiphlogistic and anti-apoptosis effects. In this study, we investigate the protection of Hyp on apoptosis of bEnd.3 cells and BBB disruption in vitro induced by Ang II.
Methods
We used bEnd.3 cells to imitate a BBB monolayer model and explored the protection of Hyp on Ang II-induced BBB leakage. The apoptotic activity was assessed by TUNEL staining and flow cytometry. The expression of apoptosis pathway related proteins, tight junction proteins and transcytosis related proteins were detected by western blot assay. The BBB model permeability was detected through measuring the flux of sodium fluorescein (Na-F).
Results
We found that Hyp can not only effectively inhibit the apoptosis of bEnd.3 induced by Ang II, but also protect the structural soundness and functional integrity of BBB model by affecting the expression levels of junctional adhesion molecule A (JAM-A), Claudin-5, zonula occludens-1 (ZO-1), Caveolin-1 (Cav-1) and major facilitator superfamily domain-containing protein 2a (Mfsd2a).
Conclusion
Hyp might be a potent compound for preventing Ang II-induced BBB disruption.
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5
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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.
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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
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6
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Molecular Regulation of Canalicular ABC Transporters. Int J Mol Sci 2021; 22:ijms22042113. [PMID: 33672718 PMCID: PMC7924332 DOI: 10.3390/ijms22042113] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 02/15/2021] [Accepted: 02/18/2021] [Indexed: 12/17/2022] Open
Abstract
The ATP-binding cassette (ABC) transporters expressed at the canalicular membrane of hepatocytes mediate the secretion of several compounds into the bile canaliculi and therefore play a key role in bile secretion. Among these transporters, ABCB11 secretes bile acids, ABCB4 translocates phosphatidylcholine and ABCG5/G8 is responsible for cholesterol secretion, while ABCB1 and ABCC2 transport a variety of drugs and other compounds. The dysfunction of these transporters leads to severe, rare, evolutionary biliary diseases. The development of new therapies for patients with these diseases requires a deep understanding of the biology of these transporters. In this review, we report the current knowledge regarding the regulation of canalicular ABC transporters' folding, trafficking, membrane stability and function, and we highlight the role of molecular partners in these regulating mechanisms.
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7
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de Trizio I, Errede M, d'Amati A, Girolamo F, Virgintino D. Expression of P-gp in Glioblastoma: What we can Learn from Brain Development. Curr Pharm Des 2020; 26:1428-1437. [PMID: 32186270 DOI: 10.2174/1381612826666200318130625] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 02/18/2020] [Indexed: 02/06/2023]
Abstract
P-Glycoprotein (P-gp) is a 170-kDa transmembrane glycoprotein that works as an efflux pump and confers multidrug resistance (MDR) in normal tissues and tumors, including nervous tissues and brain tumors. In the developing telencephalon, the endothelial expression of P-gp, and the subcellular localization of the transporter at the luminal endothelial cell (EC) plasma membrane are early hallmarks of blood-brain barrier (BBB) differentiation and suggest a functional BBB activity that may complement the placental barrier function and the expression of P-gp at the blood-placental interface. In early fetal ages, P-gp has also been immunolocalized on radial glia cells (RGCs), located in the proliferative ventricular zone (VZ) of the dorsal telencephalon and now considered to be neural progenitor cells (NPCs). RG-like NPCs have been found in many regions of the developing brain and have been suggested to give rise to neural stem cells (NSCs) of adult subventricular (SVZ) neurogenic niches. The P-gp immunosignal, associated with RG-like NPCs during cortical histogenesis, progressively decreases in parallel with the last waves of neuroblast migrations, while 'outer' RGCs and the deriving astrocytes do not stain for the efflux transporter. These data suggest that in human glioblastoma (GBM), P-gp expressed by ECs may be a negligible component of tumor MDR. Instead, tumor perivascular astrocytes may dedifferentiate and resume a progenitor-like P-gp activity, becoming MDR cells and contribute, together with perivascular P-gpexpressing glioma stem-like cells (GSCs), to the MDR profile of GBM vessels. In conclusion, the analysis of Pgp immunolocalization during brain development may contribute to identify the multiple cellular sources in the GBM vessels that may be involved in P-gp-mediated chemoresistance and can be responsible for GBM therapy failure and tumor recurrence.
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Affiliation(s)
- Ignazio de Trizio
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Human Anatomy and Histology Unit, University of Bari, School of Medicine, Bari, Italy.,Department of Neurosurgery, Neurocenter of Southern Switzerland, Regional Hospital Lugano, Lugano, Switzerland
| | - Mariella Errede
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Human Anatomy and Histology Unit, University of Bari, School of Medicine, Bari, Italy
| | - Antonio d'Amati
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Human Anatomy and Histology Unit, University of Bari, School of Medicine, Bari, Italy
| | - Francesco Girolamo
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Human Anatomy and Histology Unit, University of Bari, School of Medicine, Bari, Italy
| | - Daniela Virgintino
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Human Anatomy and Histology Unit, University of Bari, School of Medicine, Bari, Italy
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8
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VEGF/VEGFR-2 system exerts neuroprotection against Phoneutria nigriventer spider envenomation through PI3K-AKT-dependent pathway. Toxicon 2020; 185:76-90. [PMID: 32649934 DOI: 10.1016/j.toxicon.2020.06.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 06/23/2020] [Accepted: 06/23/2020] [Indexed: 01/19/2023]
Abstract
This study was undertaken to elucidate why VEGF/VEGFR-2 is elevated in the hippocampus of rats injected with Phoneutria nigriventer spider venom (PNV). PNV delays Na+ channels inactivation; blocks Ca2+ and K+ channels, increases glutamate release, causes blood-brain breakdown (BBBb), brain edema and severe excitotoxicity. Analytical FT-IR spectroscopy showed profound alteration in molecular biochemical state, with evidences for VEGFR-2 (KDR/Flk-1) signaling mediation. By blocking VEGF/VEGFR-2 binding via pre-treatment with itraconazole we demonstrated that animals' condition was deteriorated soon at 1-2 h post-PNV exposure concurrently with decreased expression of VEGF, BBB-associated proteins, ZO-1, β-catenin, laminin, P-gp (P-glycoprotein), Neu-N (neuron's viability marker) and MAPKphosphorylated-p38, while phosphorylated-ERK and Src pathways were increased. At 5 h and coinciding with incipient signs of animals' recuperation, the proteins associated with protection (HIF-1α, VEGF, VEGFR-1, VEGFR-2, Neu-N, occludin, β-catenin, laminin, P-gp efflux protein, phosphorylated-p38) increased thus indicating p38 pathway activation together with paracellular route strengthening. However, the BBB transcellular trafficking and caspase-3 increased (pro-apoptotic pathway activation). At 24 h, the transcellular route reestablished physiological state but the pro-survival pathway PI3K/(p-Akt) dropped in animals underwent VEGF/VEGFR-2 binding inhibition, whereas it was significantly activated at matched interval in PNV group without prior itraconazole; these results demonstrate impaired VEGF' survival effects at 24 h. The inhibition of VEGF/VEGFR-2 binding identified 5 h as turning point at which multi-level dynamic interplay was elicited to reverse hippocampal damage. Collectively, the data confirmed VEGFR-2 signaling via serine-threonine kinase Akt as neuroprotective pathway against PNV-induced damage. Further studies are needed to elucidate mechanisms underlying PNV effects.
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9
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Olaniyan OT, Dare A, Okotie GE, Adetunji CO, Ibitoye BO, Bamidele OJ, Eweoya OO. Testis and blood-testis barrier in Covid-19 infestation: role of angiotensin-converting enzyme 2 in male infertility. J Basic Clin Physiol Pharmacol 2020; 31:jbcpp-2020-0156. [PMID: 33006953 DOI: 10.1515/jbcpp-2020-0156] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 08/21/2020] [Indexed: 02/07/2023]
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS- CoV-2) that causes COVID-19 infections penetrates body cells by binding to angiotensin-converting enzyme-2 (ACE2) receptors. Evidence shows that SARS-CoV-2 can also affect the urogenital tract. Hence, it should be given serious attention when treating COVID-19-infected male patients of reproductive age group. Other viruses like HIV, mumps, papilloma and Epstein-Barr can induce viral orchitis, germ cell apoptosis, inflammation and germ cell destruction with attending infertility and tumors. The blood-testis barrier (BTB) and blood-epididymis barrier (BEB) are essential physical barricades in the male reproductive tract located between the blood vessel and seminiferous tubules in the testes. Despite the significant role of these barriers in male reproductive function, studies have shown that a wide range of viruses can still penetrate the barriers and induce testicular dysfunctions. Therefore, this mini-review highlights the role of ACE2 receptors in promoting SARS-CoV-2-induced blood-testis/epididymal barrier infiltration and testicular dysfunction.
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Affiliation(s)
- Olugbemi T Olaniyan
- Laboratory for Reproductive Biology and Developmental Programming, Department of Physiology, Edo University Iyamho, Iyamho, Nigeria
| | - Ayobami Dare
- Department of Physiology, School of Laboratory Medicine and Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Westville, Durban, South Africa
| | - Gloria E Okotie
- Department of Physiology, University of Ibadan, Ibadan, Nigeria
| | - Charles O Adetunji
- Applied Microbiology, Department of Microbiology, Biotechnology and Nanotechnology Laboratory, Edo University Iyamho, Iyamho, Edo State, Nigeria
| | | | - Okoli J Bamidele
- Institute of Chemical and Biotechnology, Faculty of Computer and Applied Sciences, Vaal University of Technology, Southern Gauteng Science and Technology Park, Department of Chemistry, Vanderbijlpark, South Africa
| | - Olugbenga O Eweoya
- Department of Anatomical Sciences, School of Medicine and Allied Health Sciences, University of the Gambia, Banjul, The Gambia
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10
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Arroyo G, Bustos JA, Lescano AG, Gonzales I, Saavedra H, Rodriguez S, Pretell EJ, Bonato PS, Lanchote VL, Takayanagui OM, Horton J, Gonzalez AE, Gilman RH, Garcia HH. Albendazole Sulfoxide Plasma Levels and Efficacy of Antiparasitic Treatment in Patients With Parenchymal Neurocysticercosis. Clin Infect Dis 2020; 69:1996-2002. [PMID: 30715265 DOI: 10.1093/cid/ciz085] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 01/25/2019] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND The efficacy of albendazole therapy in patients with parenchymal neurocysticercosis (NCC) is suboptimal. Plasma levels of albendazole sulfoxide (ASOX), the active metabolite of albendazole, are highly variable among patients. We hypothesized that high ASOX plasma levels during albendazole therapy may be associated with an increased antiparasitic efficacy. METHODS ASOX plasma levels were measured at treatment day 7 in 118 patients with parenchymal NCC enrolled in a treatment trial. The relationships between increasing ASOX plasma levels with the proportion of cysts resolved and the proportion of patients with complete cyst resolution (evaluated by 6-month brain magnetic resonance) were assessed. RESULTS There was a trend toward a higher proportion of cysts resolved and a higher proportion of patients cured with increasing quartiles of ASOX plasma levels. In patients with 3 or more brain cysts, the regression analysis adjusted by the concomitant administration of praziquantel (PZQ) showed a 2-fold increase in the proportion of cysts resolved (risk ratio [RR], 1.98; 95% confidence interval [CI], 1.01-3.89; P = .048) and 2.5-fold increase in the proportion of patients cured (RR, 2.45; 95% CI, .94-6.36; P = .067) when ASOX levels in the highest vs the lowest quartile were compared. No association was found in patients with 1-2 brain cysts. CONCLUSIONS We suggest an association between high ASOX plasma levels and increased antiparasitic efficacy in patients with parenchymal NCC. Nonetheless, this association is also influenced by other factors including parasite burden and concomitant administration of PZQ. These findings may serve to individualize and/or adjust therapy schemes to avoid treatment failure.
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Affiliation(s)
| | - Javier A Bustos
- Department of Microbiology, School of Sciences, Lima.,Center for Global Health, Universidad Peruana Cayetano Heredia, Lima.,Cysticercosis Unit, Instituto Nacional de Ciencias Neurológicas, Lima
| | | | - Isidro Gonzales
- Cysticercosis Unit, Instituto Nacional de Ciencias Neurológicas, Lima
| | - Herbert Saavedra
- Cysticercosis Unit, Instituto Nacional de Ciencias Neurológicas, Lima
| | - Silvia Rodriguez
- Cysticercosis Unit, Instituto Nacional de Ciencias Neurológicas, Lima
| | | | - Pierina S Bonato
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, United Kingdom
| | - Vera L Lanchote
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, United Kingdom
| | - Osvaldo M Takayanagui
- Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo Brasil, United Kingdom
| | | | - Armando E Gonzalez
- School of Veterinary Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru
| | - Robert H Gilman
- Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland
| | - Hector H Garcia
- Department of Microbiology, School of Sciences, Lima.,Center for Global Health, Universidad Peruana Cayetano Heredia, Lima.,Cysticercosis Unit, Instituto Nacional de Ciencias Neurológicas, Lima
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11
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K C S, Kakoty V, Marathe S, Chitkara D, Taliyan R. Exploring the Neuroprotective Potential of Rosiglitazone Embedded Nanocarrier System on Streptozotocin Induced Mice Model of Alzheimer's Disease. Neurotox Res 2020; 39:240-255. [PMID: 32683650 DOI: 10.1007/s12640-020-00258-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 07/06/2020] [Accepted: 07/13/2020] [Indexed: 12/23/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder imposing great threat to an individual's cognitive capability. Mounting evidence suggests that type 2 diabetes mellitus (T2DM) and AD is closely associated with impaired insulin signalling and glucose metabolism in the brain. Member of the peroxisome proliferator-activated receptor (PPAR) family, especially PPARγ agonists, has been well known for their insulin-sensitizing actions, but due to low water solubility, poor penetration into the brain and associated toxicity limit their use clinically. Therefore, this study has been undertaken to investigate the neuroprotective potential of rosiglitazone embedded nanocarrier system on streptozotocin (STZ) induced mice model of AD. In vitro neuroprotective efficacy of rosiglitazone was determined on SH-SY5Y cells by assessing the messenger ribonulceic acid (mRNA) expression level of genes implicated for cognitive function. AD in mice was developed by intracerebroventricular (ICV) administration of STZ (3 mg/kg) directly into the lateral ventricles of the mice brain. The cognitive parameters and mRNA expression levels were evaluated after treatment with the free form of rosiglitazone as well as its nano-formulated form. It was observed that rosiglitazone elicits neuroprotection on SH-SY5Y cells as evidenced from the upregulation of genes such as cyclic-AMP response element-binding protein (CREB), brain-derived neurotrophic factor (BDNF), glial cell derived neurotrophic factor (GDNF), and nerve growth factor (NGF), which are involved in cognitive functions. Further, the nano-formulated rosiglitazone induced better neuroprotective efficacy than its free drug treatment on animal model of AD as evidenced by attenuating the behavioural and cognitive abnormalities, oxido-nitrosative stress and pro-inflammatory cytokines, i.e. tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6a) along with improved antioxidant enzymes (superoxide dismutase (SOD), reduced glutathione (GSH), acetylcholine, neuronal density and expression of CREB, BDNF, GDNF and NGF in the hippocampal region. Based on the results, it can be concluded that rosiglitazone nanoformulation exerts strong neuroprotection via increasing the mRNA expression of growth factors and inhibition of oxidative stress, and neuroinflammation eventually prevents neuronal injury in AD.
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Affiliation(s)
- Sarathlal K C
- Neuropsychopharmacology Division, Department of Pharmacy, Birla Institute of Technology and Science, Pilani, Rajasthan, 333031, India
| | - Violina Kakoty
- Neuropsychopharmacology Division, Department of Pharmacy, Birla Institute of Technology and Science, Pilani, Rajasthan, 333031, India
| | - Sandhya Marathe
- Department of Cancer Biology, Birla Institute of Technology and Science, Pilani, Rajasthan, 333031, India
| | - Deepak Chitkara
- Neuropsychopharmacology Division, Department of Pharmacy, Birla Institute of Technology and Science, Pilani, Rajasthan, 333031, India
| | - Rajeev Taliyan
- Neuropsychopharmacology Division, Department of Pharmacy, Birla Institute of Technology and Science, Pilani, Rajasthan, 333031, India.
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12
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Hoshi Y, Uchida Y, Tachikawa M, Ohtsuki S, Couraud PO, Suzuki T, Terasaki T. Oxidative stress-induced activation of Abl and Src kinases rapidly induces P-glycoprotein internalization via phosphorylation of caveolin-1 on tyrosine-14, decreasing cortisol efflux at the blood-brain barrier. J Cereb Blood Flow Metab 2020; 40:420-436. [PMID: 30621530 PMCID: PMC7370610 DOI: 10.1177/0271678x18822801] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Exposure of the brain to high levels of glucocorticoids during ischemia-reperfusion induces neuronal cell death. Oxidative stress alters blood-brain barrier (BBB) function during ischemia-reperfusion, and so we hypothesized that it might impair P-glycoprotein (P-gp)-mediated efflux transport of glucocorticoids at the BBB. Therefore, the purpose of this study was to clarify the molecular mechanism of this putative decrease of P-gp-mediated efflux function. First, we established that H2O2 treatment of a human in vitro BBB model (hCMEC/D3) reduced both P-gp efflux transport activity and protein expression on the plasma membrane within 20 min. These results suggested that the rapid decrease of efflux function might be due to internalization of P-gp. Furthermore, H2O2 treatment markedly increased tyrosine-14-phosphorylated caveolin-1, which is involved in P-gp internalization. A brain perfusion study in rats showed that cortisol efflux at the BBB was markedly decreased by H2O2 administration, and inhibitors of Abl kinase and Src kinase, which phosphorylate tyrosine-14 in caveolin-1, suppressed this decrease. Overall, these findings support the idea that oxidative stress-induced activation of Abl kinase and Src kinase induces internalization of P-gp via the phosphorylation of tyrosine-14 in caveolin-1, leading to a rapid decrease of P-gp-mediated cortisol efflux at the BBB.
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Affiliation(s)
- Yutaro Hoshi
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Yasuo Uchida
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Masanori Tachikawa
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Sumio Ohtsuki
- Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | | | - Takashi Suzuki
- Department of Pathology and Histotechnology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Tetsuya Terasaki
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
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13
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Yu Y, Nie X, Song Z, Xie Y, Zhang X, Du Z, Wei R, Fan D, Liu Y, Zhao Q, Peng X, Jia L, Wang X. Signal Detection of Potentially Drug-Induced Liver Injury in Children Using Electronic Health Records. Front Pediatr 2020; 8:171. [PMID: 32373564 PMCID: PMC7177017 DOI: 10.3389/fped.2020.00171] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 03/25/2020] [Indexed: 12/28/2022] Open
Abstract
Background: This study proposes a quantitative 2-stage procedure to detect potential drug-induced liver injury (DILI) signals in pediatric inpatients using an data warehouse of electronic health records (EHRs). Methods: Eight years of medical data from a constructed database were used. A two-stage procedure was adopted: (i) stage 1: the drugs suspected of inducing DILI were selected and (ii) stage 2: the associations between the drugs and DILI were identified in a retrospective cohort study. Results: 1,196 drugs were filtered initially and 12 drugs were further potentially identified as suspect drugs inducing DILI. Eleven drugs (fluconazole, omeprazole, sulfamethoxazole, vancomycin, granulocyte colony-stimulating factor (G-CSF), acetaminophen, nifedipine, fusidine, oseltamivir, nystatin and meropenem) were showed to be associated with DILI. Of these, two drugs, nystatin [odds ratio[OR]=1.39, 95%CI:1.10-1.75] and G-CSF (OR = 1.91, 95%CI:1.55-2.35), were found to be new potential signals in adults and children. Three drugs [nifedipine [OR = 1.77, 95%CI:1.26-2.46], fusidine [OR = 1.43, 95%CI:1.08-1.86], and oseltamivi r [OR = 1.64, 95%CI:1.23-2.18]] were demonstrated to be new signals in pediatrics. The other drug-DILI associations had been confirmed in previous studies. Conclusions: A quantitative algorithm to detect potential signals of DILI has been described. Our work promotes the application of EHR data in pharmacovigilance and provides candidate drugs for further causality assessment studies.
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Affiliation(s)
- Yuncui Yu
- Clinical Research Center, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Xiaolu Nie
- Center for Clinical Epidemiology and Evidence-Based Medicine, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Ziyang Song
- Department of Pharmacy, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Yuefeng Xie
- Information Center, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Xuan Zhang
- Clinical Research Center, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Zhaoyang Du
- Department of Pharmacy, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Ran Wei
- Clinical Research Center, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Duanfang Fan
- Clinical Research Center, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Yiwei Liu
- Department of Public Health and Preventive Medicine, School of Medicine, Keio University, Tokyo, Japan
| | - Qiuye Zhao
- Center of Big Data in Medicine, Beijing Institute of Big Data Research, Beijing, China
| | - Xiaoxia Peng
- Center for Clinical Epidemiology and Evidence-Based Medicine, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Lulu Jia
- Clinical Research Center, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Xiaoling Wang
- Department of Pharmacy, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
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14
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Fan Y, Si W, Ji W, Wang Z, Gao Z, Tian R, Song W, Zhang H, Niu R, Zhang F. Rack1 mediates Src binding to drug transporter P-glycoprotein and modulates its activity through regulating Caveolin-1 phosphorylation in breast cancer cells. Cell Death Dis 2019; 10:394. [PMID: 31113938 PMCID: PMC6529477 DOI: 10.1038/s41419-019-1633-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 05/02/2019] [Accepted: 05/06/2019] [Indexed: 12/24/2022]
Abstract
The failure of chemotherapy and the emergence of multidrug resistance (MDR) are the major obstacles for effective therapy in locally advanced and metastatic breast cancer. Overexpression of the drug transporter P-glycoprotein (P-gp) in cancer cells is one of the main causes of MDR due to its ability to efflux anticancer drugs out of cells. Although the signaling node that regulates the expression of P-gp has been intensively investigated; the regulatory mechanism underlying P-gp transport activity remains obscure. Herein, we reported that Rack1 and tyrosine kinase Src confer drug resistance through modulating the transport function of P-gp without altering its protein level. We provide evidences that Rack1 and Src regulate P-gp activity by modulating caveolin-1 (Cav1) phosphorylation. Importantly, Rack1 acts as a signaling hub and mediates Src binding to P-gp, thereby facilitating the phosphorylation of Cav1 by Src and abolishing the inhibitory effect of Cav1 on P-gp. Taken together, our results demonstrate the pivotal roles of Rack1 and Src in modulating P-gp activity in drug-resistant cells. Our findings also provide novel insights into the mechanism regulating P-gp transport activity. Rack1 may represent a new target for the development of effective therapies for reversing drug resistance.
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Affiliation(s)
- Yanling Fan
- Public Laboratory, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin, 300060, China.,Key Laboratory of Cancer Prevention and Therapy, Tianjin, 300060, China.,Tianjin's Clinical Research Center for Cancer, Tianjin, 300060, China.,Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, 300060, China
| | - Weiyao Si
- Public Laboratory, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin, 300060, China.,Key Laboratory of Cancer Prevention and Therapy, Tianjin, 300060, China.,Tianjin's Clinical Research Center for Cancer, Tianjin, 300060, China.,Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, 300060, China
| | - Wei Ji
- Public Laboratory, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin, 300060, China.,Key Laboratory of Cancer Prevention and Therapy, Tianjin, 300060, China.,Tianjin's Clinical Research Center for Cancer, Tianjin, 300060, China.,Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, 300060, China
| | - Zhiyong Wang
- Public Laboratory, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin, 300060, China.,Key Laboratory of Cancer Prevention and Therapy, Tianjin, 300060, China.,Tianjin's Clinical Research Center for Cancer, Tianjin, 300060, China.,Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, 300060, China
| | - Zicong Gao
- Public Laboratory, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin, 300060, China.,Key Laboratory of Cancer Prevention and Therapy, Tianjin, 300060, China.,Tianjin's Clinical Research Center for Cancer, Tianjin, 300060, China.,Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, 300060, China
| | - Ran Tian
- Public Laboratory, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin, 300060, China.,Key Laboratory of Cancer Prevention and Therapy, Tianjin, 300060, China.,Tianjin's Clinical Research Center for Cancer, Tianjin, 300060, China.,Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, 300060, China
| | - Weijie Song
- Public Laboratory, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin, 300060, China.,Key Laboratory of Cancer Prevention and Therapy, Tianjin, 300060, China.,Tianjin's Clinical Research Center for Cancer, Tianjin, 300060, China.,Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, 300060, China
| | - He Zhang
- Public Laboratory, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin, 300060, China.,Key Laboratory of Cancer Prevention and Therapy, Tianjin, 300060, China.,Tianjin's Clinical Research Center for Cancer, Tianjin, 300060, China.,Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, 300060, China
| | - Ruifang Niu
- Public Laboratory, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin, 300060, China. .,Key Laboratory of Cancer Prevention and Therapy, Tianjin, 300060, China. .,Tianjin's Clinical Research Center for Cancer, Tianjin, 300060, China. .,Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, 300060, China.
| | - Fei Zhang
- Public Laboratory, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin, 300060, China. .,Key Laboratory of Cancer Prevention and Therapy, Tianjin, 300060, China. .,Tianjin's Clinical Research Center for Cancer, Tianjin, 300060, China. .,Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, 300060, China.
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15
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Eser Ocak P, Ocak U, Tang J, Zhang JH. The role of caveolin-1 in tumors of the brain - functional and clinical implications. Cell Oncol (Dordr) 2019; 42:423-447. [PMID: 30993541 DOI: 10.1007/s13402-019-00447-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/04/2019] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Caveolin-1 (cav-1) is the major structural protein of caveolae, the flask-shaped invaginations of the plasma membrane mainly involved in cell signaling. Today, cav-1 is believed to play a role in a variety of disease processes including cancer, owing to the variations of its expression in association with tumor progression, invasive behavior, metastasis and therapy resistance. Since first detected in the brain, a number of studies has particularly focused on the role of cav-1 in the various steps of brain tumorigenesis. In this review, we discuss the different roles of cav-1 and its contributions to the molecular mechanisms underlying the pathobiology and natural behavior of brain tumors including glial, non-glial and metastatic subtypes. These contributions could be attributed to its co-localization with important players in tumorigenesis within the lipid-enriched domains of the plasma membrane. In that regard, the ability of cav-1 to interact with various cell signaling molecules as well as the impact of caveolae depletion on important pathways acting in brain tumor pathogenesis are noteworthy. We also discuss conversant causes hampering the treatment of malignant glial tumors such as limited transport of chemotherapeutics across the blood tumor barrier and resistance to chemoradiotherapy, by focusing on the molecular fundamentals involving cav-1 participation. CONCLUSIONS Cav-1 has the potential to pivot the molecular basis underlying the pathobiology of brain tumors, particularly the malignant glial subtype. In addition, the regulatory effect of cav-1-dependent and caveola-mediated transcellular transport on the permeability of the blood tumor barrier could be of benefit to overcome the restricted transport across brain barriers when applying chemotherapeutics. The association of cav-1 with tumors of the brain other than malignant gliomas deserves to be underlined, as well given the evidence suggesting its potential in predicting tumor grade and recurrence rates together with determining patient prognosis in oligodendrogliomas, ependymomas, meningiomas, vestibular schwannomas and brain metastases.
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Affiliation(s)
- Pinar Eser Ocak
- Department of Physiology and Pharmacology, Loma Linda University School of Medicine, Loma Linda, CA, 92354, USA
| | - Umut Ocak
- Department of Physiology and Pharmacology, Loma Linda University School of Medicine, Loma Linda, CA, 92354, USA
| | - Jiping Tang
- Department of Physiology and Pharmacology, Loma Linda University School of Medicine, Loma Linda, CA, 92354, USA
| | - John H Zhang
- Department of Physiology and Pharmacology, Loma Linda University School of Medicine, Loma Linda, CA, 92354, USA. .,Department of Anesthesiology, Loma Linda University School of Medicine, Loma Linda, CA, 92354, USA. .,Department of Neurology, Loma Linda University School of Medicine, Loma Linda, CA, 92354, USA. .,Department of Neurosurgery, Loma Linda University School of Medicine, Loma Linda, CA, 92354, USA.
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16
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Taylor J, Bebawy M. Proteins Regulating Microvesicle Biogenesis and Multidrug Resistance in Cancer. Proteomics 2019; 19:e1800165. [PMID: 30520565 DOI: 10.1002/pmic.201800165] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 12/02/2018] [Indexed: 01/01/2023]
Abstract
Microvesicles (MV) are emerging as important mediators of intercellular communication. While MVs are important signaling vectors for many physiological processes, they are also implicated in cancer pathology and progression. Cellular activation is perhaps the most widely reported initiator of MV biogenesis, however, the precise mechanism remains undefined. Uncovering the proteins involved in regulating MV biogenesis is of interest given their role in the dissemination of deleterious cancer traits. MVs shed from drug-resistant cancer cells transfer multidrug resistance (MDR) proteins to drug-sensitive cells and confer the MDR phenotype in a matter of hours. MDR is attributed to the overexpression of ABC transporters, primarily P-glycoprotein and MRP1. Their expression and functionality is dependent on a number of proteins. In particular, FERM domain proteins have been implicated in supporting the functionality of efflux transporters in drug-resistant cells and in recipient cells during intercellular transfer by vesicles. Herein, the most recent research on the proteins involved in MV biogenesis and in the dissemination of MV-mediated MDR are discussed. Attention is drawn to unanswered questions in the literature that may prove to be of benefit in ongoing efforts to improve clinical response to chemotherapy and circumventing MDR.
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Affiliation(s)
- Jack Taylor
- Discipline of Pharmacy, Graduate School of Health, The University of Technology Sydney, Sydney, Australia
| | - Mary Bebawy
- Discipline of Pharmacy, Graduate School of Health, The University of Technology Sydney, Sydney, Australia
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17
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Lee VR, Vera A, Alexander A, Ruck B, Nelson LS, Wax P, Campleman S, Brent J, Calello DP. Loperamide misuse to avoid opioid withdrawal and to achieve a euphoric effect: high doses and high risk. Clin Toxicol (Phila) 2018; 57:175-180. [DOI: 10.1080/15563650.2018.1510128] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Vincent R. Lee
- Department of Emergency Medicine, Morristown Medical Center, Morristown, NJ, USA
| | - Ariel Vera
- Department of Emergency Medicine, Morristown Medical Center, Morristown, NJ, USA
| | - Andreia Alexander
- Department of Emergency Medicine, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Bruce Ruck
- Department of Emergency Medicine, New Jersey Poison Information and Education System, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Lewis S. Nelson
- Department of Emergency Medicine, New Jersey Poison Information and Education System, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Paul Wax
- UT Southwestern Medical School, Dallas, TX, USA
- American College of Medical Toxicology, Phoenix, AZ, USA
| | | | - Jeffrey Brent
- American College of Medical Toxicology, Phoenix, AZ, USA
- School of Medicine, University of Colorado, Aurora, CO, USA
| | - Diane P. Calello
- Department of Emergency Medicine, New Jersey Poison Information and Education System, Rutgers New Jersey Medical School, Newark, NJ, USA
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18
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Tome ME, Jarvis CK, Schaefer CP, Jacobs LM, Herndon JM, Hunn KC, Arkwright NB, Kellohen KL, Mierau PC, Davis TP. Acute pain alters P-glycoprotein-containing protein complexes in rat cerebral microvessels: Implications for P-glycoprotein trafficking. J Cereb Blood Flow Metab 2018; 38:2209-2222. [PMID: 30346224 PMCID: PMC6282220 DOI: 10.1177/0271678x18803623] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
P-glycoprotein (PgP) is the major drug efflux pump in human cerebral microvessels. PgP prevents pathogens, toxins and therapeutic drugs from entering the CNS. Understanding the molecular regulation of PgP activity will suggest novel mechanisms to improve CNS drug delivery. Previously, we found that during peripheral inflammatory pain (PIP) (3 h after λ carrageenan injection in the rat paw), PgP traffics to the cortical microvessel endothelial cell plasma membrane concomitant with increased PgP activity. In the current study, we measured the changes in composition of PgP-containing protein complexes after PIP in rat microvessel isolates. We found that a portion of the PgP is contained in a multi-protein complex that also contains the caveolar proteins CAV1, SDPR, PTRF and PRKCDBP. With PIP, total CAV1 bound to PgP was unchanged; however, phosphorylated CAV1 (Y14P-CAV1) in the complex increased. There were few PgP/CAV1 complexes relative to total PgP and CAV1 in the microvessels suggesting CAV1 bound to PgP is unlikely to affect total PgP activity. However, both PgP and CAV1 trafficked away from the nucleus in response to PIP. These data suggest that P-CAV1 bound to PgP potentially regulates PgP trafficking and contributes to the acute PgP activity increase after a PIP stimulus.
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Affiliation(s)
- Margaret E Tome
- Department of Pharmacology, University of Arizona, Tucson, AZ, USA
| | - Chelsea K Jarvis
- Department of Pharmacology, University of Arizona, Tucson, AZ, USA
| | | | - Leigh M Jacobs
- Department of Pharmacology, University of Arizona, Tucson, AZ, USA
| | - Joseph M Herndon
- Department of Pharmacology, University of Arizona, Tucson, AZ, USA
| | - Kristen C Hunn
- Department of Pharmacology, University of Arizona, Tucson, AZ, USA
| | | | | | - Peyton C Mierau
- Department of Pharmacology, University of Arizona, Tucson, AZ, USA
| | - Thomas P Davis
- Department of Pharmacology, University of Arizona, Tucson, AZ, USA
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19
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Stavrovskaya AA, Rybalkina EY. Recent Advances in the Studies of Molecular Mechanisms Regulating Multidrug Resistance in Cancer Cells. BIOCHEMISTRY (MOSCOW) 2018; 83:779-786. [PMID: 30200862 DOI: 10.1134/s0006297918070015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Here we present new approaches to better understanding multidrug resistance (MDR) development in cancer cells, such as identification of components of a complex process of MDR evolution. Recent advances in the studies of MDR are discussed: 1) chemotherapy agents might be involved in the selection of cancer stem cells resulting in the elevated drug resistance and enhanced tumorigenicity; 2) cell-cell interactions have a great effect on the MDR emergence and evolution; 3) mechanotransduction is an important signaling mechanism in cell-cell interactions; 4) proteins of the ABC transporter family which are often involved in MDR might be transferred between cells via microvesicles (epigenetic MDR regulation); 5) proteins providing cell-to-cell transfer of functional P-glycoprotein (MDR1 protein) via microvesicles have been investigated; 6) P-glycoprotein may serve to regulate apoptosis, as well as transcription and translation of target genes/proteins. Although proving once again that MDR is a complex multi-faceted process, these data open new approaches to overcoming it.
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Affiliation(s)
- A A Stavrovskaya
- Blokhin Medical Research Center of Oncology, Ministry of Health of the Russian Federation, Moscow, 115478, Russia.
| | - E Yu Rybalkina
- Blokhin Medical Research Center of Oncology, Ministry of Health of the Russian Federation, Moscow, 115478, Russia
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20
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Liu W, Guan X, Yu Z, Chen K, Benet L, Zhai S. A Drug-drug Interaction Between Cyclosporine and Nystatin. Clin Ther 2018; 40:660-662. [PMID: 29551534 DOI: 10.1016/j.clinthera.2018.02.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 02/04/2018] [Accepted: 02/09/2018] [Indexed: 11/26/2022]
Abstract
We present a case of increased cyclosporine concentration and liver function right after the combinational use of cyclosporine and nystatin, which indicated a drug-drug interaction between them. Both the concentration and liver function were decreased after discontinuation of nystatin and remained normal after taking on cyclosporine again. To our knowledge, this is the first case report of the interactions between nystatin and cyclosporine. Enteric P-glycoprotein could play an important role in the pharmacokinetic profile of cyclosporine, which needs further identification by physicians and pharmacists.
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Affiliation(s)
- Wei Liu
- Department of Pharmacy, Peking University Third Hospital, Beijing, China; Center of Peking University Therapeutic Drug Monitoring and Clinical Toxicology, Beijing, China
| | - Xin Guan
- Department of Dermatology, Peking University Third Hospital, Beijing, China
| | - Zhiheng Yu
- Department of Pharmacy, Peking University Third Hospital, Beijing, China
| | - Ken Chen
- Department of Pharmacy, Peking University Third Hospital, Beijing, China
| | - Leslie Benet
- Department of Pharmacy, Peking University Third Hospital, Beijing, China; University of California San Francisco, San Francisco, California
| | - Suodi Zhai
- Department of Pharmacy, Peking University Third Hospital, Beijing, China; Center of Peking University Therapeutic Drug Monitoring and Clinical Toxicology, Beijing, China.
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21
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The pericyte-glia interface at the blood-brain barrier. Clin Sci (Lond) 2018; 132:361-374. [PMID: 29439117 DOI: 10.1042/cs20171634] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 01/04/2018] [Accepted: 01/04/2018] [Indexed: 12/30/2022]
Abstract
The cerebrovasculature is a multicellular structure with varying rheological and permeability properties. The outer wall of the brain capillary endothelium is enclosed by pericytes and astrocyte end feet, anatomically assembled to guarantee barrier functions. We, here, focus on the pericyte modifications occurring in disease conditions, reviewing evidence supporting the interplay amongst pericytes, the endothelium, and glial cells in health and pathology. Deconstruction and reactivity of pericytes and glial cells around the capillary endothelium occur in response to traumatic brain injury, epilepsy, and neurodegenerative disorders, impacting vascular permeability and participating in neuroinflammation. As this represents a growing field of research, addressing the multicellular reorganization occurring at the outer wall of the blood-brain barrier (BBB) in response to an acute insult or a chronic disease could disclose novel disease mechanisms and therapeutic targets.
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22
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Pokharel D, Roseblade A, Oenarto V, Lu JF, Bebawy M. Proteins regulating the intercellular transfer and function of P-glycoprotein in multidrug-resistant cancer. Ecancermedicalscience 2017; 11:768. [PMID: 29062386 PMCID: PMC5636210 DOI: 10.3332/ecancer.2017.768] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2017] [Indexed: 12/15/2022] Open
Abstract
Chemotherapy is an essential part of anticancer treatment. However, the overexpression of P-glycoprotein (P-gp) and the subsequent emergence of multidrug resistance (MDR) hampers successful treatment clinically. P-gp is a multidrug efflux transporter that functions to protect cells from xenobiotics by exporting them out from the plasma membrane to the extracellular space. P-gp inhibitors have been developed in an attempt to overcome P-gp-mediated MDR; however, lack of specificity and dose limiting toxicity have limited their effectiveness clinically. Recent studies report on accessory proteins that either directly or indirectly regulate P-gp expression and function and which are necessary for the establishment of the functional phenotype in cancer cells. This review discusses the role of these proteins, some of which have been recently proposed to comprise an interactive complex, and discusses their contribution towards MDR. We also discuss the role of other pathways and proteins in regulating P-gp expression in cells. The potential for these proteins as novel therapeutic targets provides new opportunities to circumvent MDR clinically.
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Affiliation(s)
- Deep Pokharel
- Discipline of Pharmacy, The Graduate School of Health, The University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Ariane Roseblade
- Discipline of Pharmacy, The Graduate School of Health, The University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Vici Oenarto
- Discipline of Pharmacy, The Graduate School of Health, The University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Jamie F Lu
- Discipline of Pharmacy, The Graduate School of Health, The University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Mary Bebawy
- Discipline of Pharmacy, The Graduate School of Health, The University of Technology Sydney, Sydney, NSW 2007, Australia.,Laboratory of Cancer Cell Biology and Therapeutics, The University of Technology Sydney, Sydney, NSW 2007, Australia
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23
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Rodriguez-Grande B, Ichkova A, Lemarchant S, Badaut J. Early to Long-Term Alterations of CNS Barriers After Traumatic Brain Injury: Considerations for Drug Development. AAPS JOURNAL 2017; 19:1615-1625. [PMID: 28905273 DOI: 10.1208/s12248-017-0123-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2017] [Accepted: 07/11/2017] [Indexed: 01/06/2023]
Abstract
Traumatic brain injury (TBI) is one of the leading causes of death and disability, particularly amongst the young and the elderly. The functions of the blood-brain barrier (BBB) and blood-cerebrospinal fluid barrier (BCSFB) are strongly impaired after TBI, thus affecting brain homeostasis. Following the primary mechanical injury that characterizes TBI, a secondary injury develops over time, including events such as edema formation, oxidative stress, neuroinflammation, and alterations in paracelullar and transcellular transport. To date, most therapeutic interventions for TBI have aimed at direct neuroprotection during the acute phase and have not been successful. Targeting the barriers of the central nervous system (CNS) could be a wider therapeutic approach, given that restoration of brain homeostasis would benefit all brain cells, including neurons. Importantly, BBB disregulation has been observed even years after TBI, concomitantly with neurological and psychosocial sequelae; however, treatments targeting the post-acute phase are scarce. Here, we review the mechanisms of primary and secondary injury of CNS barriers, the accumulating evidence showing long-term damage to these structures and some of the therapies that have targeted these mechanisms. Finally, we discuss how the injury characteristics (hemorrhagic vs non-hemorrhagic, involvement of head rotation, gray vs white matter), the sex, and the age of the patient need to be carefully considered to improve clinical trial design and outcome interpretation, and to improve future drug development.
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Affiliation(s)
| | - Aleksandra Ichkova
- CNRS UMR5287, University of Bordeaux, 146 rue Léo Saignat, 33076, Bordeaux Cedex, France
| | - Sighild Lemarchant
- CNRS UMR5287, University of Bordeaux, 146 rue Léo Saignat, 33076, Bordeaux Cedex, France
| | - Jerome Badaut
- CNRS UMR5287, University of Bordeaux, 146 rue Léo Saignat, 33076, Bordeaux Cedex, France. .,Basic Science Departments, Loma Linda University School of Medicine, Loma Linda, California, USA.
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24
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Ichkova A, Rodriguez-Grande B, Bar C, Villega F, Konsman JP, Badaut J. Vascular impairment as a pathological mechanism underlying long-lasting cognitive dysfunction after pediatric traumatic brain injury. Neurochem Int 2017; 111:93-102. [PMID: 28377126 DOI: 10.1016/j.neuint.2017.03.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Revised: 03/29/2017] [Accepted: 03/31/2017] [Indexed: 12/11/2022]
Abstract
Traumatic brain injury (TBI) is the leading cause of death and disability in children. Indeed, the acute mechanical injury often evolves to a chronic brain disorder with long-term cognitive, emotional and social dysfunction even in the case of mild TBI. Contrary to the commonly held idea that children show better recovery from injuries than adults, pediatric TBI patients actually have worse outcome than adults for the same injury severity. Acute trauma to the young brain likely interferes with the fine-tuned developmental processes and may give rise to long-lasting consequences on brain's function. This review will focus on cerebrovascular dysfunction as an important early event that may lead to long-term phenotypic changes in the brain after pediatric TBI. These, in turn may be associated with accelerated brain aging and cognitive dysfunction. Finally, since no effective treatments are currently available, understanding the unique pathophysiological mechanisms of pediatric TBI is crucial for the development of new therapeutic options.
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Affiliation(s)
| | | | - Claire Bar
- CNRS UMR 5287, INCIA, University of Bordeaux, France; Department of Pediatric Neurology, University Children's Hospital of Bordeaux, France
| | - Frederic Villega
- Department of Pediatric Neurology, University Children's Hospital of Bordeaux, France
| | | | - Jerome Badaut
- CNRS UMR 5287, INCIA, University of Bordeaux, France; Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA, USA.
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25
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Bastian TW, Duck KA, Michalopoulos GC, Chen MJ, Liu ZJ, Connor JR, Lanier LM, Sola-Visner MC, Georgieff MK. Eltrombopag, a thrombopoietin mimetic, crosses the blood-brain barrier and impairs iron-dependent hippocampal neuron dendrite development. J Thromb Haemost 2017; 15:565-574. [PMID: 28005311 PMCID: PMC5334144 DOI: 10.1111/jth.13602] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Indexed: 11/29/2022]
Abstract
Essentials Potential neurodevelopmental side effects of thrombopoietin mimetics need to be considered. The effects of eltrombopag (ELT) on neuronal iron status and dendrite development were assessed. ELT crosses the blood-brain barrier and causes iron deficiency in developing neurons. ELT blunts dendrite maturation, indicating a need for more safety studies before neonatal use. SUMMARY Background Thrombocytopenia is common in sick neonates. Thrombopoietin mimetics (e.g. eltrombopag [ELT]) might provide an alternative therapy for selected neonates with severe and prolonged thrombocytopenia, and for infants and young children with different varieties of thrombocytopenia. However, ELT chelates intracellular iron, which may adversely affect developing organs with high metabolic requirements. Iron deficiency (ID) is particularly deleterious during brain development, impairing neuronal myelination, dopamine signaling and dendritic maturation and ultimately impairing long-term neurological function (e.g. hippocampal-dependent learning and memory). Objective To determine whether ELT crosses the blood-brain barrier (BBB), causes neuronal ID and impairs hippocampal neuron dendrite maturation. Methods ELT transport across the BBB was assessed using primary bovine brain microvascular endothelial cells. Embryonic mouse primary hippocampal neuron cultures were treated with ELT or deferoxamine (DFO, an iron chelator) from 7 days in vitro (DIV) through 14 DIV and assessed for gene expression and neuronal dendrite complexity. Results ELT crossed the BBB in a time-dependent manner. 2 and 6 μm ELT increased Tfr1 and Slc11a2 (iron-responsive genes involved in neuronal iron uptake) mRNA levels, indicating neuronal ID. 6 μm ELT, but not 2 μm ELT, decreased BdnfVI, Camk2a and Vamp1 mRNA levels, suggesting impaired neuronal development and synaptic function. Dendrite branch number and length were reduced in 6 μm ELT-treated neurons, resulting in blunted dendritic arbor complexity that was similar to DFO-treated neurons. Conclusions Eltrombopag treatment during development may impair neuronal structure as a result of neuronal ID. Preclinical in vivo studies are warranted to assess ELT safety during periods of rapid brain development.
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Affiliation(s)
- Thomas W. Bastian
- Department of Pediatrics, School of Medicine, University of Minnesota, Minneapolis, MN
- Department of Neuroscience, University of Minnesota, Minneapolis, MN
- Center for Neurobehavioral Development, School of Medicine, University of Minnesota, Minneapolis, MN
| | - Kari A. Duck
- Department of Neurosurgery, The Pennsylvania State University, Hershey, PA
| | | | - Michael J. Chen
- Department of Neurosurgery, The Pennsylvania State University, Hershey, PA
| | - Zhi-Jian Liu
- Division of Newborn Medicine, Boston Children's Hospital, Boston, MA
| | - James R. Connor
- Department of Neurosurgery, The Pennsylvania State University, Hershey, PA
| | - Lorene M. Lanier
- Department of Neuroscience, University of Minnesota, Minneapolis, MN
- Center for Neurobehavioral Development, School of Medicine, University of Minnesota, Minneapolis, MN
| | | | - Michael K. Georgieff
- Department of Pediatrics, School of Medicine, University of Minnesota, Minneapolis, MN
- Center for Neurobehavioral Development, School of Medicine, University of Minnesota, Minneapolis, MN
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26
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Bustos ML, Zhao Y, Chen H, Caritis SN, Venkataramanan R. Polymorphisms in CYP1A1 and CYP3A5 Genes Contribute to the Variability in Granisetron Clearance and Exposure in Pregnant Women with Nausea and Vomiting. Pharmacotherapy 2016; 36:1238-1244. [PMID: 27809336 DOI: 10.1002/phar.1860] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Nausea and vomiting affect up to 90% of pregnant women. Granisetron is a potent and highly selective serotonin receptor antagonist and is an effective antiemetic. Findings from a prior study in pregnant women demonstrated a large interindividual variability in granisetron exposure. Granisetron is primarily metabolized by the cytochrome P450 (CYP) enzymes CYP1A1 and CYP3A and is likely a substrate of the ABCB1 transporter. Single-nucleotide polymorphisms (SNPs) in CYP3A, CYP1A1, and ABCB1 can alter drug metabolism. OBJECTIVE This study evaluated the influence of polymorphisms in CYP3A4, CYP3A5, CYP1A1, and ABCB1 on the pharmacokinetic properties of granisetron in pregnant women. METHODS The study enrolled 16 pregnant women (gestational age of 12-19 wks). All patients had nausea and vomiting and were treated with granisetron 1 mg. Granisetron plasma concentrations were determined using liquid chromatography tandem-mass spectrometry. The patients' genotype was determined using TaqMan SNP Genotyping Assays. The Hardy-Weinberg equilibrium was assessed by comparing observed and expected genotype frequencies, using the exact test. Intravenous granisetron clearance was used as the dependent variable for analysis of associations. RESULTS Of 16 patients, 25% were homozygous for the allele variant CYP3A5*3 and had a significantly lower granisetron clearance and increased area under the plasma concentration-versus-time curve (AUC) compared with nonhomozygous patients. Approximately one-third of patients (n=5) were carriers for the allele variant CYP1A1*2A and had a significantly higher granisetron clearance and decreased AUC. We did not find significant differences in the AUC or clearance for any SNPs in CYP3A4 and ABCB1 genes. CONCLUSIONS Polymorphisms in CYP3A5 and CYP1A1 account for some of the variability in systemic clearance and exposure of granisetron in pregnant women.
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Affiliation(s)
- Martha L Bustos
- Department of Pharmaceutical Sciences, University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania
| | - Yang Zhao
- Department of Pharmaceutical Sciences, University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania
| | - Huijun Chen
- Department of Pharmaceutical Sciences, University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania
| | - Steve N Caritis
- University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Raman Venkataramanan
- Department of Pharmaceutical Sciences, University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania.,Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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27
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Tome ME, Herndon JM, Schaefer CP, Jacobs LM, Zhang Y, Jarvis CK, Davis TP. P-glycoprotein traffics from the nucleus to the plasma membrane in rat brain endothelium during inflammatory pain. J Cereb Blood Flow Metab 2016; 36:1913-1928. [PMID: 27466374 PMCID: PMC5094312 DOI: 10.1177/0271678x16661728] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 06/28/2016] [Indexed: 02/01/2023]
Abstract
P-glycoprotein (PgP), a drug efflux pump in blood-brain barrier endothelial cells, is a major clinical obstacle for effective central nervous system drug delivery. Identifying PgP regulatory pathways that can be exploited clinically is critical for improving central nervous system drug delivery. We previously found that PgP activity increases in rat brain microvessels concomitant with decreased central nervous system drug delivery in response to acute peripheral inflammatory pain. In the current study, we tested the hypothesis that PgP traffics to the luminal plasma membrane of the microvessel endothelial cells from intracellular stores during peripheral inflammatory pain. Using immunofluorescence microscopy, we detected PgP in endothelial cell nuclei and in the luminal plasma membrane in control animals. Following peripheral inflammatory pain, luminal PgP staining increased while staining in the nucleus decreased. Biochemical analysis of nuclear PgP content confirmed our visual observations. Peripheral inflammatory pain also increased endothelial cell luminal staining of polymerase 1 and transcript release factor/cavin1 and serum deprivation response protein/cavin2, two caveolar scaffold proteins, without changing caveolin1 or protein kinase C delta binding protein/cavin3 location. Our data (a) indicate that PgP traffics from stores in the nucleus to the endothelial cell luminal membrane in response to peripheral inflammatory pain; (b) provide an explanation for our previous observation that peripheral inflammatory pain inhibits central nervous system drug uptake; and (c) suggest a novel regulatory mechanism for PgP activity in rat brain.
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Affiliation(s)
- Margaret E Tome
- Department of Pharmacology, University of Arizona, Tucson, USA
| | | | | | - Leigh M Jacobs
- Department of Pharmacology, University of Arizona, Tucson, USA
| | - Yifeng Zhang
- Department of Pharmacology, University of Arizona, Tucson, USA
| | | | - Thomas P Davis
- Department of Pharmacology, University of Arizona, Tucson, USA
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28
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Jullienne A, Obenaus A, Ichkova A, Savona-Baron C, Pearce WJ, Badaut J. Chronic cerebrovascular dysfunction after traumatic brain injury. J Neurosci Res 2016; 94:609-22. [PMID: 27117494 PMCID: PMC5415378 DOI: 10.1002/jnr.23732] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Revised: 02/11/2016] [Accepted: 02/28/2016] [Indexed: 12/12/2022]
Abstract
Traumatic brain injuries (TBI) often involve vascular dysfunction that leads to long-term alterations in physiological and cognitive functions of the brain. Indeed, all the cells that form blood vessels and that are involved in maintaining their proper function can be altered by TBI. This Review focuses on the different types of cerebrovascular dysfunction that occur after TBI, including cerebral blood flow alterations, autoregulation impairments, subarachnoid hemorrhage, vasospasms, blood-brain barrier disruption, and edema formation. We also discuss the mechanisms that mediate these dysfunctions, focusing on the cellular components of cerebral blood vessels (endothelial cells, smooth muscle cells, astrocytes, pericytes, perivascular nerves) and their known and potential roles in the secondary injury cascade. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Amandine Jullienne
- Department of Pediatrics, Loma Linda University School of Medicine, Loma Linda, California
| | - Andre Obenaus
- Department of Pediatrics, Loma Linda University School of Medicine, Loma Linda, California
- Department of Physiology, Loma Linda University School of Medicine, Loma Linda, California
- Center for Glial-Neuronal Interactions, Division of Biomedical Sciences, University of California Riverside, Riverside, California
| | | | | | - William J Pearce
- Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, California
| | - Jerome Badaut
- Department of Physiology, Loma Linda University School of Medicine, Loma Linda, California
- CNRS UMR5287, University of Bordeaux, Bordeaux, France
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29
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Kim DG, Bynoe MS. A2A adenosine receptor modulates drug efflux transporter P-glycoprotein at the blood-brain barrier. J Clin Invest 2016; 126:1717-33. [PMID: 27043281 PMCID: PMC4855938 DOI: 10.1172/jci76207] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 02/18/2016] [Indexed: 11/17/2022] Open
Abstract
The blood-brain barrier (BBB) protects the brain from toxic substances within the peripheral circulation. It maintains brain homeostasis and is a hurdle for drug delivery to the CNS to treat neurodegenerative diseases, including Alzheimer's disease and brain tumors. The drug efflux transporter P-glycoprotein (P-gp) is highly expressed on brain endothelial cells and blocks the entry of most drugs delivered to the brain. Here, we show that activation of the A2A adenosine receptor (AR) with an FDA-approved A2A AR agonist (Lexiscan) rapidly and potently decreased P-gp expression and function in a time-dependent and reversible manner. We demonstrate that downmodulation of P-gp expression and function coincided with chemotherapeutic drug accumulation in brains of WT mice and in primary mouse and human brain endothelial cells, which serve as in vitro BBB models. Lexiscan also potently downregulated the expression of BCRP1, an efflux transporter that is highly expressed in the CNS vasculature and other tissues. Finally, we determined that multiple pathways, including MMP9 cleavage and ubiquitinylation, mediated P-gp downmodulation. Based on these data, we propose that A2A AR activation on BBB endothelial cells offers a therapeutic window that can be fine-tuned for drug delivery to the brain and has potential as a CNS drug-delivery technology.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily B/biosynthesis
- ATP Binding Cassette Transporter, Subfamily B/genetics
- ATP Binding Cassette Transporter, Subfamily G, Member 2/biosynthesis
- ATP Binding Cassette Transporter, Subfamily G, Member 2/blood
- ATP Binding Cassette Transporter, Subfamily G, Member 2/genetics
- Adenosine A2 Receptor Agonists/pharmacology
- Animals
- Blood-Brain Barrier/metabolism
- Cell Line
- Endothelial Cells/metabolism
- Gene Expression Regulation
- Humans
- Matrix Metalloproteinase 9/genetics
- Matrix Metalloproteinase 9/metabolism
- Mice
- Neoplasm Proteins/blood
- Neoplasm Proteins/genetics
- Proteolysis/drug effects
- Purines/pharmacology
- Pyrazoles/pharmacology
- Receptor, Adenosine A2A/genetics
- Receptor, Adenosine A2A/metabolism
- Ubiquitination/drug effects
- Ubiquitination/genetics
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30
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Wu M, Li T, Chen L, Peng S, Liao W, Bai R, Zhao X, Yang H, Wu C, Zeng H, Liu Y. Essential oils from Inula japonica and Angelicae dahuricae enhance sensitivity of MCF-7/ADR breast cancer cells to doxorubicin via multiple mechanisms. JOURNAL OF ETHNOPHARMACOLOGY 2016; 180:18-27. [PMID: 26795076 DOI: 10.1016/j.jep.2016.01.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2015] [Revised: 11/26/2015] [Accepted: 01/18/2016] [Indexed: 06/05/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Angelicae dahurica (Hoffm.) Benth. & Hook.f.ex Franch. & Sav combined with Pueraria and Gastrodia elata Bl. combined with Inula japonica Thunb. are widely used in herb-pairs of traditional chinese medicine. Previous studies have shown that Angelicae dahuricae essential oil (ADO) enhanced puerarin internalization into ABCB1-overexpressed Caco-2 cells. These findings suggest the possibility that essential oils may enhance the absorption via certain mechanisms related to ABCB1 and reverse multidrug resistance (MDR). AIM OF THE STUDY ADO and essential oils from Inula japonica (IJO) may reverse ABCB1-mediated MDR, but this ability has not been investigated in detail in the well-established cancer cell lines. In this study, the underlying molecular mechanisms were further investigated to examine how IJO and ADO reverse MDR in the resistant human breast cancer cell line of MCF-7/ADR. Also this work may help uncover the conceivable compatibility mechanisms of above herb-pairs involved in ABCB1. MATERIALS AND METHODS The MDR human breast cancer MCF-7/ADR cells were treated with IJO, its sesquiterpene component isoalantolactone (ISO) or ADOat non- cytotoxic concentrations. The MDR ability was examined by measuring the sensitivity to doxorubicin (DOX), DOX accumulation and efflux, ABCB1 ATPase activity, ABCB1 expression, membrane fluidity, and stability and localization of lipid rafts and caveolae. Finally, the molecular modeling was performed to postulate how ISO interacts with ABCB1. RESULTS Treating MCF-7/ADR cells with IJ oil, ISO or AD oil reversed MDR 2- to 3-fold, without affecting the sensitivity of the non-MDR parental cell line. Mechanistic studies showed that these oils down-regulated mRNA and protein expression of ABCB1, and reduced the stability of lipid rafts in the cell membrane, which has previously been shown to reduce ABCB1-mediated transport. On the other hand, IJO, ISO and ADO did not inhibit ABCB1 ATPase activity, and fluorescence polarization experiments showed that low concentrations of the oils did not appear to alter membrane fluidity, unlike some MDR-reversing agents, ISO showed a higher docking score than verapamil but lower than dofequidar and tariquidar. CONCLUSIONS Our results suggest that IJO, ISO and ADO could reverse MDR by down-regulating ABCB1 expression and reducing lipid raft stability. These findings may be useful for developing safer and effective MDR reversal agents and also help find out the compatibility mechanisms.
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Affiliation(s)
- Min Wu
- Department of Biophysics, School of Life Science and Technology, University of Electronic Science and Technology of China, PR China; Department of Pharmacy, Chengdu Medical College, Chengdu 610081, Sichuan, PR China.
| | - Tingting Li
- Department of Biophysics, School of Life Science and Technology, University of Electronic Science and Technology of China, PR China.
| | - Lilan Chen
- Department of Pharmacy, Chengdu Medical College, Chengdu 610081, Sichuan, PR China.
| | - Sugang Peng
- Department of Pharmacy, Chengdu Medical College, Chengdu 610081, Sichuan, PR China.
| | - Wei Liao
- Department of Pharmacy, Chengdu Medical College, Chengdu 610081, Sichuan, PR China.
| | - Ruolan Bai
- Department of Pharmacy, Chengdu Medical College, Chengdu 610081, Sichuan, PR China.
| | - Xue Zhao
- Department of Pharmacy, Chengdu Medical College, Chengdu 610081, Sichuan, PR China.
| | - Hong Yang
- Department of Biophysics, School of Life Science and Technology, University of Electronic Science and Technology of China, PR China; Center for Information in Biomedicine, University of Electronic Science and Technology of China, Chengdu 610054, Sichuan, PR China.
| | - Chunhui Wu
- Department of Biophysics, School of Life Science and Technology, University of Electronic Science and Technology of China, PR China; Center for Information in Biomedicine, University of Electronic Science and Technology of China, Chengdu 610054, Sichuan, PR China.
| | - Hongjuan Zeng
- Department of Biophysics, School of Life Science and Technology, University of Electronic Science and Technology of China, PR China; Center for Information in Biomedicine, University of Electronic Science and Technology of China, Chengdu 610054, Sichuan, PR China.
| | - Yiyao Liu
- Department of Biophysics, School of Life Science and Technology, University of Electronic Science and Technology of China, PR China; Center for Information in Biomedicine, University of Electronic Science and Technology of China, Chengdu 610054, Sichuan, PR China.
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31
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Lee CY, Lai TY, Tsai MK, Ou-Yang P, Tsai CY, Wu SW, Hsu LC, Chen JS. The influence of a caveolin-1 mutant on the function of P-glycoprotein. Sci Rep 2016; 6:20486. [PMID: 26843476 PMCID: PMC4740904 DOI: 10.1038/srep20486] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 01/05/2016] [Indexed: 12/02/2022] Open
Abstract
The genetic heterogeneity in cancer cells has an increased chance in the acquisition of new mutant such as drug-resistant phenotype in cancer cells. The phenotype of drug resistance in cancer cells could be evaluated by the number or function of drug transporters on cell membranes, which would lead to decreased intracellular anti-cancer drugs concentration. Caveolae are flask-shaped invaginations on cell membrane that function in membrane trafficking, endocytosis, and as a compartment where receptors and signaling proteins are concentrated. Caveolin-1 (CAV1) is the principal structural protein of caveolae and closely correlates with multidrug resistance in cancer cells. In a systematic study of the ubiquitin-modified proteome, lysine 176 of CAV1 was identified as a potential post-translational modification site for ubiquitination. In this article, we identified a mutation at lysine 176 to arginine (K176R) on CAV1 would interfere with the biogenesis of caveolae and broke the interaction of CAV1 with P-glycoprotein. Functional assays further revealed that K176R mutant of CAV1 in cancer cells increased the transport activity of P-glycoprotein and decreased the killing ability of anti-cancer drugs in non-small-cell lung cancer cell lines.
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Affiliation(s)
- Chih-Yuan Lee
- Department of Surgery, No. 7 Chung San South Road, Taipei 10002, Taiwan.,Institute of Molecular Medicine, College of Medicine, National Taiwan University, No. 1 Jen-Ai Road, Sec. 1, Taipei 10002, Taiwan
| | - Ting-Yu Lai
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, No. 1 Jen-Ai Road, Sec. 1, Taipei 10002, Taiwan
| | - Meng-Kun Tsai
- Department of Surgery, No. 7 Chung San South Road, Taipei 10002, Taiwan
| | - Pu Ou-Yang
- Department of Medical Research, National Taiwan University Hospital, No. 7 Chung San South Road, Taipei 10002, Taiwan
| | - Ching-Yi Tsai
- Department of Medical Research, National Taiwan University Hospital, No. 7 Chung San South Road, Taipei 10002, Taiwan
| | - Shu-Wei Wu
- Department of Surgery, No. 7 Chung San South Road, Taipei 10002, Taiwan
| | - Li-Chung Hsu
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, No. 1 Jen-Ai Road, Sec. 1, Taipei 10002, Taiwan
| | - Jin-Shing Chen
- Department of Surgery, No. 7 Chung San South Road, Taipei 10002, Taiwan
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32
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Qosa H, Miller DS, Pasinelli P, Trotti D. Regulation of ABC efflux transporters at blood-brain barrier in health and neurological disorders. Brain Res 2015; 1628:298-316. [PMID: 26187753 PMCID: PMC4681613 DOI: 10.1016/j.brainres.2015.07.005] [Citation(s) in RCA: 158] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2015] [Revised: 06/28/2015] [Accepted: 07/02/2015] [Indexed: 01/16/2023]
Abstract
The strength of the blood-brain barrier (BBB) in providing protection to the central nervous system from exposure to circulating chemicals is maintained by tight junctions between endothelial cells and by a broad range of transporter proteins that regulate exchange between CNS and blood. The most important transporters that restrict the permeability of large number of toxins as well as therapeutic agents are the ABC transporters. Among them, P-gp, BCRP, MRP1 and MRP2 are the utmost studied. These efflux transporters are neuroprotective, limiting the brain entry of neurotoxins; however, they could also restrict the entry of many therapeutics and contribute to CNS pharmacoresistance. Characterization of several regulatory pathways that govern expression and activity of ABC efflux transporters in the endothelium of brain capillaries have led to an emerging consensus that these processes are complex and contain several cellular and molecular elements. Alterations in ABC efflux transporters expression and/or activity occur in several neurological diseases. Here, we review the signaling pathways that regulate expression and transport activity of P-gp, BCRP, MRP1 and MRP2 as well as how their expression/activity changes in neurological diseases. This article is part of a Special Issue entitled SI: Neuroprotection.
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Affiliation(s)
- Hisham Qosa
- Weinberg Unit for ALS Research, Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, 900 Walnut street, Philadelphia, PA 19107, USA.
| | - David S Miller
- Laboratory of Signal Transduction, NIH/NIEHS, Research Triangle Park, NC 27709, USA
| | - Piera Pasinelli
- Weinberg Unit for ALS Research, Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, 900 Walnut street, Philadelphia, PA 19107, USA
| | - Davide Trotti
- Weinberg Unit for ALS Research, Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, 900 Walnut street, Philadelphia, PA 19107, USA.
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33
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Lam J, Baello S, Iqbal M, Kelly LE, Shannon PT, Chitayat D, Matthews SG, Koren G. The ontogeny of P-glycoprotein in the developing human blood-brain barrier: implication for opioid toxicity in neonates. Pediatr Res 2015; 78:417-21. [PMID: 26086643 DOI: 10.1038/pr.2015.119] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 03/23/2015] [Indexed: 12/29/2022]
Abstract
BACKGROUND Neonates have been shown to have a heightened sensitivity to the central depressive effects of opioids compared to older infants and adults. The limited development of P-glycoprotein (P-gp) may limit the ability of the neonate to efflux morphine from the brain back to the systemic circulation. The objective of the study was to determine the ontogeny of P-gp in the human brain. METHODS Postmortem cortex samples from gestational age (GA) 20-26 wk, GA 36-40 wk, postnatal age (PNA) 0-3 mo, PNA 3-6 mo, and adults were immunostained for P-gp. RESULTS The intensity of P-gp staining in adults was significantly higher compared to at GA 20-26 wk (P < 0.05), GA 36-40 wk (P < 0.05), and PNA 0-3 mo (P < 0.05). P-gp intensity at GA 20-26 wk (P < 0.05), GA 36-40 wk (P < 0.05), and PNA 0-3 mo (P < 0.05) was significantly lower compared to at PNA 3-6 mo. CONCLUSION P-gp expression in the brain is limited at birth, increases with postnatal maturation, and reaches adult levels at ~3-6 mo of age. Given the immaturity of blood-brain barrier (BBB) P-gp after birth, morphine may concentrate in the brain. This provides mechanistic support to life threatening opioid toxicity seen with maternal codeine use during breastfeeding.
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Affiliation(s)
- Jessica Lam
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada.,Division of Clinical Pharmacology and Toxicology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Stephanie Baello
- Department of Physiology, Obstetrics and Gynaecology, University of Toronto, Toronto, Ontario, Canada
| | - Majid Iqbal
- Division of Clinical Pharmacology and Toxicology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Lauren E Kelly
- Department of Physiology and Pharmacology, University of Western Ontario, Toronto, Ontario, Canada
| | - Patrick T Shannon
- Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - David Chitayat
- Department of Obstetrics and Gynaecology, Prenatal Diagnosis and Medical Genetics Program, Mount Sinai Hospital, Toronto, Ontario, Canada.,Division of Clinical and Metabolic Genetics, Department of Pediatrics, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Stephen G Matthews
- Department of Physiology, Obstetrics and Gynaecology, University of Toronto, Toronto, Ontario, Canada
| | - Gideon Koren
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada.,Division of Clinical Pharmacology and Toxicology, The Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Physiology and Pharmacology, University of Western Ontario, Toronto, Ontario, Canada
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Tome ME, Schaefer CP, Jacobs LM, Zhang Y, Herndon JM, Matty FO, Davis TP. Identification of P-glycoprotein co-fractionating proteins and specific binding partners in rat brain microvessels. J Neurochem 2015; 134:200-10. [PMID: 25832806 DOI: 10.1111/jnc.13106] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 02/26/2015] [Accepted: 03/23/2015] [Indexed: 11/27/2022]
Abstract
Drug delivery to the brain for the treatment of pathologies with a CNS component is a significant clinical challenge. P-glycoprotein (PgP), a drug efflux pump in the endothelial cell membrane, is a major factor in preventing therapeutics from crossing the blood-brain barrier (BBB). Identifying PgP regulatory mechanisms is key to developing agents to modulate PgP activity. Previously, we found that PgP trafficking was altered concomitant with increased PgP activity and disassembly of high molecular weight PgP-containing complexes during acute peripheral inflammatory pain. These data suggest that PgP activity is post-translationally regulated at the BBB. The goal of the current study was to identify proteins that co-localize with PgP in rat brain microvessel endothelial cell membrane microdomains and use the data to suggest potential regulatory mechanisms. Using new density gradients of microvessel homogenates, we identified two unique pools (1,2) of PgP in membrane fractions. Caveolar constituents, caveolin1, cavin1, and cavin2, co-localized with PgP in these fractions indicating the two pools contained caveolae. A chaperone (Hsc71), protein disulfide isomerase and endosomal/lysosomal sorting proteins (Rab5, Rab11a) also co-fractionated with PgP in the gradients. These data suggest signaling pathways with a potential role in post-translational regulation of PgP activity at the BBB.
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Affiliation(s)
- Margaret E Tome
- Department of Medical Pharmacology, University of Arizona, Tucson, Arizona, USA
| | - Charles P Schaefer
- Department of Medical Pharmacology, University of Arizona, Tucson, Arizona, USA
| | - Leigh M Jacobs
- Department of Medical Pharmacology, University of Arizona, Tucson, Arizona, USA
| | - Yifeng Zhang
- Department of Medical Pharmacology, University of Arizona, Tucson, Arizona, USA
| | - Joseph M Herndon
- Department of Medical Pharmacology, University of Arizona, Tucson, Arizona, USA
| | - Fabian O Matty
- Department of Medical Pharmacology, University of Arizona, Tucson, Arizona, USA
| | - Thomas P Davis
- Department of Medical Pharmacology, University of Arizona, Tucson, Arizona, USA
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Jaiswal R, Raymond Grau GE, Bebawy M. Cellular communication via microparticles: role in transfer of multidrug resistance in cancer. Future Oncol 2015; 10:655-69. [PMID: 24754595 DOI: 10.2217/fon.13.230] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Multidrug resistance (MDR) continues to be a major impediment to the successful treatment of cancer. The two efflux transporters, P-glycoprotein (P-gp) and MRP1 are major contributors to cancer MDR clinically. The upregulation of P-gp leading to MDR was initially understood to occur via pre- and post-transcriptional mechanisms only. However, we demonstrated that microparticles mediate the intercellular exchange and trafficking of bioactive material, including functional P-gp and selected modulatory miRNAs. This exchange of P-gp leads to the dissemination of MDR within a cancer cell population. These findings have significant implications in understanding the cellular basis governing the intercellular acquisition of deleterious traits in cancers, serving to substantially advance our understanding of the molecular basis of the emergence of MDR in cancer clinically.
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Affiliation(s)
- Ritu Jaiswal
- School of Pharmacy, Graduate School of Health, The University of Technology, Sydney, NSW 2007, Australia
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Badaut J, Ajao DO, Sorensen DW, Fukuda AM, Pellerin L. Caveolin expression changes in the neurovascular unit after juvenile traumatic brain injury: signs of blood-brain barrier healing? Neuroscience 2014; 285:215-26. [PMID: 25450954 DOI: 10.1016/j.neuroscience.2014.10.035] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 10/20/2014] [Accepted: 10/22/2014] [Indexed: 01/01/2023]
Abstract
Traumatic brain injury (TBI) is one of the major causes of death and disability in pediatrics, and results in a complex cascade of events including the disruption of the blood-brain barrier (BBB). A controlled-cortical impact on post-natal 17-day-old rats induced BBB disruption by IgG extravasation from 1 to 3 days after injury and returned to normal at day 7. In parallel, we characterized the expression of three caveolin isoforms, caveolin 1 (cav-1), caveolin 2 (cav-2) and caveolin 3 (cav-3). While cav-1 and cav-2 are expressed on endothelial cells, both cav-1 and cav-3 were found to be present on reactive astrocytes, in vivo and in vitro. Following TBI, cav-1 expression was increased in blood vessels at 1 and 7 days in the perilesional cortex. An increase of vascular cav-2 expression was observed 7 days after TBI. In contrast, astrocytic cav-3 expression decreased 3 and 7 days after TBI. Activation of endothelial nitric oxide synthase (eNOS) (via its phosphorylation) was detected 1 day after TBI and phospho-eNOS was detected both in association with blood vessels and with astrocytes. The molecular changes involving caveolins occurring in endothelial cells following juvenile-TBI might participate, independently of eNOS activation, to a mechanism of BBB repair while, they might subserve other undefined roles in astrocytes.
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Affiliation(s)
- J Badaut
- CNRS UMR5287, University of Bordeaux, Bordeaux, France; Department of Physiology, Loma Linda University, Loma Linda, CA, USA; Department of Pediatrics, Loma Linda University, Loma Linda, CA, USA.
| | - D O Ajao
- Department of Physiology, Loma Linda University, Loma Linda, CA, USA
| | - D W Sorensen
- Department of Physiology, Loma Linda University, Loma Linda, CA, USA; Department of Pediatrics, Loma Linda University, Loma Linda, CA, USA
| | - A M Fukuda
- Department of Physiology, Loma Linda University, Loma Linda, CA, USA
| | - L Pellerin
- Department of Physiology, University of Lausanne, Lausanne, Switzerland
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Brito MA, Palmela I, Cardoso FL, Sá-Pereira I, Brites D. Blood–Brain Barrier and Bilirubin: Clinical Aspects and Experimental Data. Arch Med Res 2014; 45:660-76. [DOI: 10.1016/j.arcmed.2014.11.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 11/18/2014] [Indexed: 01/18/2023]
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CLN3 loss disturbs membrane microdomain properties and protein transport in brain endothelial cells. J Neurosci 2014; 33:18065-79. [PMID: 24227717 DOI: 10.1523/jneurosci.0498-13.2013] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Juvenile neuronal ceroid lipofuscinosis (JNCL) is a fatal childhood-onset neurodegenerative disorder caused by mutations in ceroid lipofuscinosis neuronal-3 (CLN3), a hydrophobic transmembrane protein of unresolved function. Previous studies indicate blood-brain barrier (BBB) defects in JNCL, and our earlier report showed prominent Cln3 expression in mouse brain endothelium. Here we find that CLN3 is necessary for normal trafficking of the microdomain-associated proteins caveolin-1, syntaxin-6, and multidrug resistance protein 1 (MDR1) in brain endothelial cells. Correspondingly, CLN3-null cells have reduced caveolae, and impaired caveolae- and MDR1-related functions including endocytosis, drug efflux, and cell volume regulation. We also detected an abnormal blood-brain barrier response to osmotic stress in vivo. Evaluation of the plasma membrane with fluorescent sphingolipid probes suggests microdomain destabilization and enhanced fluidity in CLN3-null cells. In further work we found that application of the glycosphingolipid lactosylceramide to CLN3-deficient cells rescues protein transport and caveolar endocytosis. Last, we show that CLN3 localizes to the trans-Golgi network (TGN) and partitions with buoyant microdomain fractions. We propose that CLN3 facilitates TGN-to-plasma membrane transport of microdomain-associated proteins. Insult to this pathway may underlie BBB dysfunction and contribute to JNCL pathogenesis.
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Badaut J, Bix GJ. Vascular neural network phenotypic transformation after traumatic injury: potential role in long-term sequelae. Transl Stroke Res 2013; 5:394-406. [PMID: 24323723 DOI: 10.1007/s12975-013-0304-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 10/23/2013] [Accepted: 10/24/2013] [Indexed: 01/11/2023]
Abstract
The classical neurovascular unit (NVU), composed primarily of endothelium, astrocytes, and neurons, could be expanded to include smooth muscle and perivascular nerves present in both the up- and downstream feeding blood vessels (arteries and veins). The extended NVU, which can be defined as the vascular neural network (VNN), may represent a new physiological unit to consider for therapeutic development in stroke, traumatic brain injury, and other brain disorders (Zhang et al., Nat Rev Neurol 8(12):711-716, 2012). This review is focused on traumatic brain injury and resultant post-traumatic changes in cerebral blood flow, smooth muscle cells, matrix, blood-brain barrier structures and function, and the association of these changes with cognitive outcomes as described in clinical and experimental reports. We suggest that studies characterizing TBI outcomes should increase their focus on changes to the VNN, as this may yield meaningful therapeutic targets to resolve posttraumatic dysfunction.
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Affiliation(s)
- J Badaut
- Department of Pediatrics, Loma Linda University School of Medicine, Coleman Pavilion, Room A1120, 11175 Campus Street, Loma Linda, CA, 92354, USA,
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Quann K, Gonzales DM, Mercier I, Wang C, Sotgia F, Pestell RG, Lisanti MP, Jasmin JF. Caveolin-1 is a negative regulator of tumor growth in glioblastoma and modulates chemosensitivity to temozolomide. Cell Cycle 2013; 12:1510-20. [PMID: 23598719 PMCID: PMC3680531 DOI: 10.4161/cc.24497] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Caveolin-1 (Cav-1) is a critical regulator of tumor progression in a variety of cancers where it has been shown to act as either a tumor suppressor or tumor promoter. In glioblastoma multiforme, it has been previously demonstrated to function as a putative tumor suppressor. Our studies here, using the human glioblastoma-derived cell line U-87MG, further support the role of Cav-1 as a negative regulator of tumor growth. Using a lentiviral transduction approach, we were able to stably overexpress Cav-1 in U-87MG cells. Gene expression microarray analyses demonstrated significant enrichment in gene signatures corresponding to downregulation of MAPK, PI3K/AKT and mTOR signaling, as well as activation of apoptotic pathways in Cav-1-overexpressing U-87MG cells. These same gene signatures were later confirmed at the protein level in vitro. To explore the ability of Cav-1 to regulate tumor growth in vivo, we further show that Cav-1-overexpressing U-87MG cells display reduced tumorigenicity in an ectopic xenograft mouse model, with marked hypoactivation of MAPK and PI3K/mTOR pathways. Finally, we demonstrate that Cav-1 overexpression confers sensitivity to the most commonly used chemotherapy for glioblastoma, temozolomide. In conclusion, Cav-1 negatively regulates key cell growth and survival pathways and may be an effective biomarker for predicting response to chemotherapy in glioblastoma.
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Affiliation(s)
- Kevin Quann
- Department of Stem Cell Biology & Regenerative Medicine, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
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41
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McCaffrey G, Davis TP. Physiology and pathophysiology of the blood-brain barrier: P-glycoprotein and occludin trafficking as therapeutic targets to optimize central nervous system drug delivery. J Investig Med 2012; 60:1131-40. [PMID: 23138008 PMCID: PMC3851303 DOI: 10.2310/jim.0b013e318276de79] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The blood-brain barrier (BBB) is a physical and metabolic barrier that separates the central nervous system from the peripheral circulation. Central nervous system drug delivery across the BBB is challenging, primarily because of the physical restriction of paracellular diffusion between the endothelial cells that comprise the microvessels of the BBB and the activity of efflux transporters that quickly expel back into the capillary lumen a wide variety of xenobiotics. Therapeutic manipulation of protein trafficking is emerging as a novel means of modulating protein function, and in this minireview, the targeting of the trafficking of 2 key BBB proteins, P-glycoprotein and occludin, is presented as a novel, reversible means of optimizing central nervous system drug delivery.
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Affiliation(s)
- Gwen McCaffrey
- Department of Medical Pharmacology, University of Arizona College of Medicine, Tucson, AZ 85745, USA.
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Collins BM, Davis MJ, Hancock JF, Parton RG. Structure-based reassessment of the caveolin signaling model: do caveolae regulate signaling through caveolin-protein interactions? Dev Cell 2012; 23:11-20. [PMID: 22814599 DOI: 10.1016/j.devcel.2012.06.012] [Citation(s) in RCA: 111] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Caveolin proteins drive formation of caveolae, specialized cell-surface microdomains that influence cell signaling. Signaling proteins are proposed to use conserved caveolin-binding motifs (CBMs) to associate with caveolae via the caveolin scaffolding domain (CSD). However, structural and bioinformatic analyses argue against such direct physical interactions: in the majority of signaling proteins, the CBM is buried and inaccessible. Putative CBMs do not form a common structure for caveolin recognition, are not enriched among caveolin-binding proteins, and are even more common in yeast, which lack caveolae. We propose that CBM/CSD-dependent interactions are unlikely to mediate caveolar signaling, and the basis for signaling effects should therefore be reassessed.
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Affiliation(s)
- Brett M Collins
- The Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia.
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Byrne DP, Dart C, Rigden DJ. Evaluating caveolin interactions: do proteins interact with the caveolin scaffolding domain through a widespread aromatic residue-rich motif? PLoS One 2012; 7:e44879. [PMID: 23028656 PMCID: PMC3444507 DOI: 10.1371/journal.pone.0044879] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Accepted: 08/09/2012] [Indexed: 01/08/2023] Open
Abstract
Caveolins are coat proteins of caveolae, small flask-shaped pits of the plasma membranes of most cells. Aside from roles in caveolae formation, caveolins recruit, retain and regulate many caveolae-associated signalling molecules. Caveolin-protein interactions are commonly considered to occur between a ∼20 amino acid region within caveolin, the caveolin scaffolding domain (CSD), and an aromatic-rich caveolin binding motif (CBM) on the binding partner (фXфXXXXф, фXXXXфXXф or фXфXXXXфXXф, where ф is an aromatic and X an unspecified amino acid). The CBM resembles a typical linear motif - a short, simple sequence independently evolved many times in different proteins for a specific function. Here we exploit recent improvements in bioinformatics tools and in our understanding of linear motifs to critically examine the role of CBMs in caveolin interactions. We find that sequences conforming to the CBM occur in 30% of human proteins, but find no evidence for their statistical enrichment in the caveolin interactome. Furthermore, sequence- and structure-based considerations suggest that CBMs do not have characteristics commonly associated with true interaction motifs. Analysis of the relative solvent accessible area of putative CBMs shows that the majority of their aromatic residues are buried within the protein and are thus unlikely to interact directly with caveolin, but may instead be important for protein structural stability. Together, these findings suggest that the canonical CBM may not be a common characteristic of caveolin-target interactions and that interfaces between caveolin and targets may be more structurally diverse than presently appreciated.
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Affiliation(s)
- Dominic P. Byrne
- Institute of Integrative Biology, The University of Liverpool, Liverpool, United Kingdom
| | - Caroline Dart
- Institute of Integrative Biology, The University of Liverpool, Liverpool, United Kingdom
| | - Daniel J. Rigden
- Institute of Integrative Biology, The University of Liverpool, Liverpool, United Kingdom
- * E-mail:
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44
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McCaffrey G, Staatz WD, Sanchez-Covarrubias L, Finch JD, Demarco K, Laracuente ML, Ronaldson PT, Davis TP. P-glycoprotein trafficking at the blood-brain barrier altered by peripheral inflammatory hyperalgesia. J Neurochem 2012; 122:962-75. [PMID: 22716933 DOI: 10.1111/j.1471-4159.2012.07831.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
P-glycoprotein (ABCB1/MDR1, EC 3.6.3.44), the major efflux transporter at the blood-brain barrier (BBB), is a formidable obstacle to CNS pharmacotherapy. Understanding the mechanism(s) for increased P-glycoprotein activity at the BBB during peripheral inflammatory pain is critical in the development of novel strategies to overcome the significant decreases in CNS analgesic drug delivery. In this study, we employed the λ-carrageenan pain model (using female Sprague-Dawley rats), combined with confocal microscopy and subcellular fractionation of cerebral microvessels, to determine if increased P-glycoprotein function, following the onset of peripheral inflammatory pain, is associated with a change in P-glycoprotein trafficking which leads to pain-induced effects on analgesic drug delivery. Injection of λ-carrageenan into the rat hind paw induced a localized, inflammatory pain (hyperalgesia) and simultaneously, at the BBB, a rapid change in colocalization of P-glycoprotein with caveolin-1, a key scaffolding/trafficking protein. Subcellular fractionation of isolated cerebral microvessels revealed that the bulk of P-glycoprotein constitutively traffics to membrane domains containing high molecular weight, disulfide-bonded P-glycoprotein-containing structures that cofractionate with membrane domains enriched with monomeric and high molecular weight, disulfide-bonded, caveolin-1-containing structures. Peripheral inflammatory pain promoted a dynamic redistribution between membrane domains of P-glycoprotein and caveolin-1. Disassembly of high molecular weight P-glycoprotein-containing structures within microvascular endothelial luminal membrane domains was accompanied by an increase in ATPase activity, suggesting a potential for functionally active P-glycoprotein. These results are the first observation that peripheral inflammatory pain leads to specific structural changes in P-glycoprotein responsible for controlling analgesic drug delivery to the CNS.
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Affiliation(s)
- Gwen McCaffrey
- Department of Medical Pharmacology, University of Arizona College of Medicine, Tucson, AZ 85745, USA.
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Schmitz M, Signore SC, Zerr I, Althaus HH. Oligodendroglial process formation is differentially affected by modulating the intra- and extracellular cholesterol content. J Mol Neurosci 2012; 49:457-69. [PMID: 22740150 PMCID: PMC3566395 DOI: 10.1007/s12031-012-9833-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 06/04/2012] [Indexed: 12/12/2022]
Abstract
Cholesterol is an essential component of eukaryotic plasma membranes and plays an important role in membrane organization and signaling processes. It is the major lipid component of detergent resistant caveolin-1 containing rafts which previously had been reported as a platform for nerve growth factor (NGF) signaling in oligodendrocytes (OL). Surprisingly, a knockdown of caveolin-1 attenuated the process formation of OL (Schmitz et al. J Neurosci Res 88:572–588, 2010), for which a loss of cholesterol could be responsible. In the present report, we could show that a caveolin-1 knockdown resulted in an elevation of cellular cholesterol level; it may indicate an important role of caveolin-1 in cholesterol trafficking to the plasma membrane. Treatment with exogenous PEG cholesterol, which was incorporated to the plasma membrane, supported oligodendroglial process formation, in particular when OL were stimulated by NGF. In this context we have found that OL express NPC1L1 (Niemann–Pick disease type C1-Like 1) which could modulate cholesterol uptake. In contrast, depletion of membrane-bound cholesterol diminished NGF-induced process formation concomitant with a reduced activity of p42/44 mitogen-activated protein kinases.
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Affiliation(s)
- Matthias Schmitz
- Max-Planck Institute of Experimental Medicine, RU Neural Regeneration, Hermann-Rein-Straße 3, 37075, Goettingen, Germany.
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Abstract
Glioblastoma multiforme (GBM) is the most common malignant brain tumor and is characterized by high invasiveness, poor prognosis, and limited therapeutic options. Biochemical and morphological experiments have shown the presence of caveolae in glioblastoma cells. Caveolae are flask-shaped plasma membrane subdomains that play trafficking, mechanosensing, and signaling roles. Caveolin-1 is a membrane protein that participates in the formation of caveolae and binds a multitude of signaling proteins, compartmentalizing them in caveolae and often directly regulating their activity via binding to its scaffolding domain. Caveolin-1 has been proposed to behave either as a tumor suppressor or as an ongogene depending on the tumor type and progress. This review discusses the existing information on the expression and function of caveolin-1 and caveolae in GBM and the role of this organelle and its defining protein on cellular signaling, growth, and invasiveness of GBM. We further analyze the available data suggesting caveolin-1 could be a target in GBM therapy.
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Affiliation(s)
- Marie-Odile Parat
- University of Queensland School of Pharmacy, PACE, 20 Cornwall St., Woollloongabba QLD 4102, Australia.
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Ferrándiz-Huertas C, Fernández-Carvajal A, Ferrer-Montiel A. Rab4 interacts with the human P-glycoprotein and modulates its surface expression in multidrug resistant K562 cells. Int J Cancer 2010; 128:192-205. [PMID: 20209493 DOI: 10.1002/ijc.25310] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
P-glycoprotein (P-gp) is a plasma membrane glycoprotein that has been signaled as a primary cause of multidrug resistance (MDR) in tumors. We performed a yeast 2-hybrid screen using the C-terminal domain of P-gp and identified 2 small GTPases involved in vesicular trafficking, Rab4 and Rab14, which complex with P-gp. The overexpression of GFP-Rab4, either transiently or stably, but not of Rab14, in K562ADR cells decreased the presence of P-gp in the cell surface. As a result, expression of this GTPase reduced the MDR phenotype of K562ADR cells, by augmenting the intracellular accumulation of daunomycin (DNM). This effect was mimicked by the constitutively active Rab4Q72L mutant, but not by the dominant negative Rab4S27N mutant. Rab4 regulated excocytotic P-gp trafficking to the plasma membrane from intracellular compartments, and this modulation required the interaction of both proteins and the GTPase activity. Noteworthy, K562ADR cells exhibited a significant reduction of Rab4 levels, but not of other Rab GTPases, as compared with the sensitive parental cell line, suggesting that the development of the MDR phenotype in these cells involves upregulation of P-gp and a concomitant downregulation of proteins that regulate its surface expression. Attenuation of endogenous Rab4 levels in K562ADR by RNA interference enhanced the expression of P-gp in the cell surface, and reduced the uptake of DNM. Accordingly, these findings substantiate the notion that modulation of the temporal and spatial distribution of P-gp in cancer cells may be a valid therapeutic strategy to alleviate the MDR phenotype, and signal to Rab4 as a potential target.
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Affiliation(s)
- Clotilde Ferrándiz-Huertas
- Instituto de Biología Molecular y Celular, Universidad Miguel Hernández, Av de la Universidad s/n, 03202 Elche, Alicante, Spain
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Mruk DD, Su L, Cheng CY. Emerging role for drug transporters at the blood-testis barrier. Trends Pharmacol Sci 2010; 32:99-106. [PMID: 21168226 DOI: 10.1016/j.tips.2010.11.007] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Revised: 10/26/2010] [Accepted: 11/16/2010] [Indexed: 12/22/2022]
Abstract
Drug transporters are integral membrane proteins that transport a broad range of substrates into and out of cells, usually against a concentration gradient. Studies have shown that efflux pumps such as P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) localize at the blood-testis barrier (BTB), where they protect the testis from drugs and xenobiotics that are detrimental to spermatogenesis. At the same time, efflux pumps might also preclude entry of non-hormonal contraceptives to the testis. In more recent studies, P-gp function was correlated with BTB integrity. In this review, we discuss findings that have made a significant impact on our understanding of efflux pumps in the testis. Modulation of efflux pump function via specific inhibitors could help to deliver contraceptives to the testis in the future.
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Affiliation(s)
- Dolores D Mruk
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, USA.
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49
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Roger E, Lagarce F, Garcion E, Benoit JP. Reciprocal competition between lipid nanocapsules and P-gp for paclitaxel transport across Caco-2 cells. Eur J Pharm Sci 2010; 40:422-9. [DOI: 10.1016/j.ejps.2010.04.015] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Revised: 02/02/2010] [Accepted: 04/22/2010] [Indexed: 11/28/2022]
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50
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Intact lipid rafts regulate HIV-1 Tat protein-induced activation of the Rho signaling and upregulation of P-glycoprotein in brain endothelial cells. J Cereb Blood Flow Metab 2010; 30:522-33. [PMID: 19794400 PMCID: PMC2949153 DOI: 10.1038/jcbfm.2009.214] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The Rho signaling has an essential function in human immunodeficiency virus (HIV)-1-mediated disruption of the integrity of the blood-brain barrier (BBB). However, it is unknown how membrane domains, such as lipid rafts, can influence HIV-1-mediated activation of the Rho pathway and how these processes can affect the expression of the efflux transporters at the BBB level. This study is focused on the function of HIV-1 protein Tat in activation of the Rho signaling and upregulation of P-glycoprotein (P-gp) in human brain endothelial cells. Treatment with Tat markedly elevated GTP-RhoA levels and the potential downstream effectors, such as myosin phosphatase target subunit 1 and myosin light chain. In addition, Tat upregulated expression and promoter activity of P-gp as well as its efflux function. Inhibition of the Rho signaling cascade effectively blocked P-gp overexpression at the level of promoter activity. Disruption of lipid rafts by depletion of membrane cholesterol by methyl-beta-cyclodextrin, but not caveolin-1 silencing, also abolished Tat-mediated RhoA activation and P-gp upregulation. The present data indicate the critical function of intact lipid rafts and the Rho signaling in HIV-1-mediated upregulation of P-gp and potential development of drug resistance in brain endothelial cells.
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