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TSPO PET Imaging: From Microglial Activation to Peripheral Sterile Inflammatory Diseases? CONTRAST MEDIA & MOLECULAR IMAGING 2017; 2017:6592139. [PMID: 29114179 PMCID: PMC5632884 DOI: 10.1155/2017/6592139] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 08/01/2017] [Accepted: 08/07/2017] [Indexed: 02/07/2023]
Abstract
Peripheral sterile inflammatory diseases (PSIDs) are a heterogeneous group of disorders that gathers several chronic insults involving the cardiovascular, respiratory, gastrointestinal, or musculoskeletal system and wherein inflammation is the cornerstone of the pathophysiology. In PSID, timely characterization and localization of inflammatory foci are crucial for an adequate care for patients. In brain diseases, in vivo positron emission tomography (PET) exploration of inflammation has matured over the last 20 years, through the development of radiopharmaceuticals targeting the translocator protein-18 kDa (TSPO) as molecular biomarkers of activated microglia. Recently, TSPO has been introduced as a possible molecular target for PSIDs PET imaging, making this protein a potential biomarker to address disease heterogeneity, to assist in patient stratification, and to contribute to predicting treatment response. In this review, we summarized the major research advances recently made in the field of TSPO PET imaging in PSIDs. Promising preliminary results have been reported in bowel, cardiovascular, and rheumatic inflammatory diseases, consolidated by preclinical studies. Limitations of TSPO PET imaging in PSIDs, regarding both its large expression in healthy peripheral tissues, unlike in central nervous system, and the production of peripheral radiolabeled metabolites, are also discussed, regarding their possible consequences on TSPO PET signal's quantification.
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Maruyoshi H, Maruyoshi N, Hirosue M, Ikeda K, Shimamoto M. Clonazepam-associated Bradycardia in a Disabled Elderly Woman with Multiple Complications. Intern Med 2017; 56:2301-2305. [PMID: 28794360 PMCID: PMC5635303 DOI: 10.2169/internalmedicine.8234-16] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We herein report an 87-year-old woman who was taking clonazepam at 1.5 mg/day. She was hospitalized with an old cerebral infarction complicated with symptomatic epilepsy, dementia, dyslipidemia, and chronic cholecystitis. Electrocardiogram revealed severe bradycardia at 31 beats/min. The bradycardia disappeared on day 3 after clonazepam withdrawal, although the serum clonazepam level had been within normal limits. She was diagnosed with clonazepam-associated bradycardia, which was likely related to the potential calcium channel-blocking properties of clonazepam. Because of age-related pharmacokinetic and pharmacodynamic changes, the adverse effects of clonazepam should be considered, especially in disabled elderly individuals with multiple comorbidities.
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Affiliation(s)
| | | | - Motone Hirosue
- Department of Internal Medicine, Shimamoto Hospital, Japan
| | - Komei Ikeda
- Department of Neurological Surgery, Shimamoto Hospital, Japan
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Hellberg S, Silvola JMU, Kiugel M, Liljenbäck H, Savisto N, Li XG, Thiele A, Lehmann L, Heinrich T, Vollmer S, Hakovirta H, Laine VJO, Ylä-Herttuala S, Knuuti J, Roivainen A, Saraste A. 18-kDa translocator protein ligand 18F-FEMPA: Biodistribution and uptake into atherosclerotic plaques in mice. J Nucl Cardiol 2017; 24:862-871. [PMID: 27225517 DOI: 10.1007/s12350-016-0527-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 04/01/2016] [Indexed: 10/21/2022]
Abstract
BACKGROUND Radioligands of 18-kDa translocator protein (TSPO) expressed on activated macrophages are a potential approach for imaging of inflammation in atherosclerosis. We evaluated a novel TSPO-targeted tracer 18F-FEMPA for the detection of atherosclerotic plaque inflammation in mice. METHODS AND RESULTS The distribution kinetics of 18F-FEMPA was evaluated by in vivo PET/CT imaging. 18F-FEMPA uptake was compared in atherosclerotic (LDLR-/-ApoB100/100, n = 10) and healthy mice (C57BL/6 N, n = 7) ex vivo at twenty minutes post-injection. Biodistribution was analyzed from harvested tissue samples, and aortas were sectioned for autoradiography. Aortas of LDLR-/-ApoB100/100 mice showed large, macrophage-rich atherosclerotic plaques. In vivo, 18F-FEMPA showed rapid blood clearance but no difference in aortic uptake between atherosclerotic and healthy mice. In the mice studied ex vivo at 20 minutes post-injection, quantification of radioactivity in the whole aorta showed 1.3-fold higher 18F-FEMPA accumulation in atherosclerotic than healthy mice (P = .028). Autoradiography showed higher tracer uptake in plaque areas with high macrophage content as compared with areas of no macrophages (count densities 190 ± 54 vs 40 ± 13 PSL/mm2, P < .001), but the uptake in the plaques was not higher than in the normal vessel wall (230 ± 78 PSL/mm2). In vitro blocking showed specific accumulation in mouse and human atherosclerotic plaques. Immunohistochemistry confirmed co-localization of TSPO and macrophages. CONCLUSIONS 18F-FEMPA shows rapid blood clearance and uptake in the mouse aorta. Uptake in atherosclerotic plaques correlated with the amount of macrophages, but did not exceed that in the normal vessel wall.
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Affiliation(s)
- Sanna Hellberg
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, 20520, Turku, Finland
| | - Johanna M U Silvola
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, 20520, Turku, Finland
| | - Max Kiugel
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, 20520, Turku, Finland
| | - Heidi Liljenbäck
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, 20520, Turku, Finland
- Turku Center for Disease Modeling, University of Turku, Turku, Finland
| | - Nina Savisto
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, 20520, Turku, Finland
| | - Xiang-Guo Li
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, 20520, Turku, Finland
| | | | | | | | | | | | - V Jukka O Laine
- Department of Pathology, Turku University Hospital, Turku, Finland
| | - Seppo Ylä-Herttuala
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Juhani Knuuti
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, 20520, Turku, Finland
- Turku PET Centre, Turku University Hospital, Turku, Finland
| | - Anne Roivainen
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, 20520, Turku, Finland
- Turku Center for Disease Modeling, University of Turku, Turku, Finland
- Turku PET Centre, Turku University Hospital, Turku, Finland
| | - Antti Saraste
- Turku PET Centre, University of Turku, Kiinamyllynkatu 4-8, 20520, Turku, Finland.
- Turku PET Centre, Turku University Hospital, Turku, Finland.
- Heart Center, Turku University Hospital and University of Turku, Turku, Finland.
- Institute of Clinical Medicine, University of Turku, Turku, Finland.
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Acero G, Nava Catorce M, González-Mendoza R, Meraz-Rodríguez MA, Hernández-Zimbron LF, González-Salinas R, Gevorkian G. Sodium thiosulphate attenuates brain inflammation induced by systemic lipopolysaccharide administration in C57BL/6J mice. Inflammopharmacology 2017; 25:10.1007/s10787-017-0355-y. [PMID: 28526927 DOI: 10.1007/s10787-017-0355-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 04/26/2017] [Indexed: 02/03/2023]
Abstract
It has been demonstrated that peripheral infections accompanied by neuroinflammation may modify brain development or affect normal brain aging and represent major risk factors for the development of neurological disorders. A wide range of synthetic and natural compounds with anti-inflammatory properties have been evaluated in animal models of neuroinflammation and neurodegeneration as an adjuvant therapeutic strategy. In the present study we have demonstrated for the first time that sodium thiosulphate (STS), a known antidote approved for treatment of certain medical conditions, is capable of reducing brain inflammation caused by systemic LPS administration. STS reduced brain levels of pro-inflammatory cytokine interleukin-1β (IL-1β), cyclooxygenase-2 (COX-2), ionized calcium binding adaptor molecule 1 (Iba-1) and 18 kDa translocator protein (TSPO) in an animal model of systemic LPS-induced neuroinflammation. In addition, we demonstrated for the first time elevated TSPO expression in retinal ganglion cells layer after peripheral LPS challenge and inhibition of ocular TSPO expression after treatment with STS. We think that STS may be used as an adjuvant anti-inflammatory therapy for many pathological conditions associated with inflammation in the brain.
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Affiliation(s)
- Gonzalo Acero
- Instituto de Investigaciones Biomedicas, Universidad Nacional Autonoma de Mexico (UNAM), Apartado Postal 70228, Cuidad Universitaria, Mexico DF, CP 04510, Mexico
| | - Miryam Nava Catorce
- Instituto de Investigaciones Biomedicas, Universidad Nacional Autonoma de Mexico (UNAM), Apartado Postal 70228, Cuidad Universitaria, Mexico DF, CP 04510, Mexico
| | - Ricardo González-Mendoza
- Instituto de Investigaciones Biomedicas, Universidad Nacional Autonoma de Mexico (UNAM), Apartado Postal 70228, Cuidad Universitaria, Mexico DF, CP 04510, Mexico
| | - Marco Antonio Meraz-Rodríguez
- Instituto de Investigaciones Biomedicas, Universidad Nacional Autonoma de Mexico (UNAM), Apartado Postal 70228, Cuidad Universitaria, Mexico DF, CP 04510, Mexico
| | | | | | - Goar Gevorkian
- Instituto de Investigaciones Biomedicas, Universidad Nacional Autonoma de Mexico (UNAM), Apartado Postal 70228, Cuidad Universitaria, Mexico DF, CP 04510, Mexico.
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Classical and Novel TSPO Ligands for the Mitochondrial TSPO Can Modulate Nuclear Gene Expression: Implications for Mitochondrial Retrograde Signaling. Int J Mol Sci 2017; 18:ijms18040786. [PMID: 28387723 PMCID: PMC5412370 DOI: 10.3390/ijms18040786] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Revised: 03/24/2017] [Accepted: 03/27/2017] [Indexed: 12/22/2022] Open
Abstract
It is known that knockdown of the mitochondrial 18 kDa translocator protein (TSPO) as well as TSPO ligands modulate various functions, including functions related to cancer. To study the ability of TSPO to regulate gene expression regarding such functions, we applied microarray analysis of gene expression to U118MG glioblastoma cells. Within 15 min, the classical TSPO ligand PK 11195 induced changes in expression of immediate early genes and transcription factors. These changes also included gene products that are part of the canonical pathway serving to modulate general gene expression. These changes are in accord with real-time, reverse transcriptase (RT) PCR. At the time points of 15, 30, 45, and 60 min, as well as 3 and 24 h of PK 11195 exposure, the functions associated with the changes in gene expression in these glioblastoma cells covered well known TSPO functions. These functions included cell viability, proliferation, differentiation, adhesion, migration, tumorigenesis, and angiogenesis. This was corroborated microscopically for cell migration, cell accumulation, adhesion, and neuronal differentiation. Changes in gene expression at 24 h of PK 11195 exposure were related to downregulation of tumorigenesis and upregulation of programmed cell death. In the vehicle treated as well as PK 11195 exposed cell cultures, our triple labeling showed intense TSPO labeling in the mitochondria but no TSPO signal in the cell nuclei. Thus, mitochondrial TSPO appears to be part of the mitochondria-to-nucleus signaling pathway for modulation of nuclear gene expression. The novel TSPO ligand 2-Cl-MGV-1 appeared to be very specific regarding modulation of gene expression of immediate early genes and transcription factors.
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Liu GJ, Middleton RJ, Kam WWY, Chin DY, Hatty CR, Chan RHY, Banati RB. Functional gains in energy and cell metabolism after TSPO gene insertion. Cell Cycle 2017; 16:436-447. [PMID: 28103132 PMCID: PMC5351937 DOI: 10.1080/15384101.2017.1281477] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Recent loss-of-function studies in tissue-specific as well as global Tspo (Translocator Protein 18 kDa) knockout mice have not confirmed its long assumed indispensability for the translocation of cholesterol across the mitochondrial inter-membrane space, a rate-limiting step in steroid biosynthesis. Instead, recent studies in global Tspo knockout mice indicate that TSPO may play a more fundamental role in cellular bioenergetics, which may include the indirect down-stream regulation of transport or metabolic functions. To examine whether overexpression of the TSPO protein alters the cellular bioenergetic profile, Jurkat cells with low to absent endogenous expression were transfected with a TSPO construct to create a stable cell line with de novo expression of exogenous TSPO protein. Expression of TSPO was confirmed by RT-qPCR, radioligand binding with [3H]PK11195 and immunocytochemistry with a TSPO antibody. We demonstrate that TSPO gene insertion causes increased transcription of genes involved in the mitochondrial electron transport chain. Furthermore, TSPO insertion increased mitochondrial ATP production as well as cell excitability, reflected in a decrease in patch clamp recorded rectified K channel currents. These functional changes were accompanied by an increase in cell proliferation and motility, which were inhibited by PK11195, a selective ligand for TSPO. We suggest that TSPO may serve a range of functions that can be viewed as downstream regulatory effects of its primary, evolutionary conserved role in cell metabolism and energy production.
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Affiliation(s)
- Guo-Jun Liu
- a Australian Nuclear Science and Technology Organisation , Lucas Heights , NSW , Australia.,b Faculty of Health Science and Brain and Mind Centre, University of Sydney , NSW , Australia
| | - Ryan J Middleton
- a Australian Nuclear Science and Technology Organisation , Lucas Heights , NSW , Australia
| | - Winnie Wai-Ying Kam
- a Australian Nuclear Science and Technology Organisation , Lucas Heights , NSW , Australia.,c Department of Health Technology and Informatics , Hong Kong Polytechnic University , Hung Hom, Hong Kong , China
| | - David Y Chin
- d NCRIS Biologics Facility, Australian Institute for Bioengineering and Nanotechnology, University of Queensland , QLD , Australia
| | - Claire R Hatty
- a Australian Nuclear Science and Technology Organisation , Lucas Heights , NSW , Australia.,b Faculty of Health Science and Brain and Mind Centre, University of Sydney , NSW , Australia
| | - Ronald H Y Chan
- a Australian Nuclear Science and Technology Organisation , Lucas Heights , NSW , Australia.,b Faculty of Health Science and Brain and Mind Centre, University of Sydney , NSW , Australia
| | - Richard B Banati
- a Australian Nuclear Science and Technology Organisation , Lucas Heights , NSW , Australia.,b Faculty of Health Science and Brain and Mind Centre, University of Sydney , NSW , Australia
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Cardioprotective effects of intracoronary administration of 4-chlorodiazepam in small and large animal models of ischemia-reperfusion. Int J Cardiol 2016; 224:90-95. [PMID: 27643472 DOI: 10.1016/j.ijcard.2016.09.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 08/31/2016] [Accepted: 09/08/2016] [Indexed: 11/23/2022]
Abstract
BACKGROUND The Translocator Protein (TSPO) of the mitochondrial membrane has been recognized as a potential therapeutic target for mitigation of myocardial ischemia-reperfusion injury. Administration of 4-chlorodiazepam (4-CLD), a TSPO ligand, has been shown to confer acute cardioprotective effects in small animals; however, long-term studies and studies in clinically-relevant large animal models are lacking. In the present study we investigated a potential cardioprotective effect of intracoronary administration of 4-CLD in small and large animal models of ischemia-reperfusion. METHODS Acute myocardial infarction was induced in 38 Wistar rats and 29 farm pigs by ligation of the left anterior descending coronary artery, followed by reperfusion. Animals were randomized to undergo intracoronary infusion of 2μM 4-CLD or vehicle just prior (pigs) or immediately after (rats) reperfusion. Infarcted rats were euthanized either after 1h of reperfusion (for histological assessment of the "no reflow" area) or after 60days (for serial evaluation of cardiac function and structure by echocardiography and assessment of infarct size). Infarcted pigs were euthanized after 2h of reperfusion for histological assessment of infarct size and "no reflow" area. RESULTS In infarcted rats, intracoronary infusion of 4-CLD resulted in acute reduction of the "no reflow" area and conferred durable long-term structural and functional benefits (reduction in infarct size, attenuation of adverse remodeling, improvement in global systolic function). In infarcted pigs, intracoronary infusion of 4-CLD was well-tolerated from a hemodynamic standpoint and resulted in acute reduction in infarct size, reduction in "no reflow" area and more rapid resolution of ST-segment elevation. CONCLUSIONS In a rat model of myocardial infarction, intracoronary administration of 4-CLD attenuated the "no reflow" phenomenon and produced long-term structural and functional benefits. In a porcine model of myocardial infarction intracoronary administration of 4-CLD did not raise safety concerns and conferred acute cardioprotective effects.
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Antidepressant-Like and Anxiolytic-Like Effects of ZBD-2, a Novel Ligand for the Translocator Protein (18 kDa). Neuromolecular Med 2016; 19:57-68. [PMID: 27544207 DOI: 10.1007/s12017-016-8425-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 07/02/2016] [Indexed: 12/17/2022]
Abstract
Activation of translocator protein (18 kDa) (TSPO) plays an important role to mediate rapid anxiolytic efficacy in stress response and stress-related disorders by the production of neurosteroids. However, little is known about the ligand of TSPO on the anxiety-like and depressive behaviors and the underlying mechanisms in chronic unpredictable mild stress (UCMS) mice. In the present study, a novel ligand of TSPO, ZBD-2 [N-benzyl-N-ethyl-2-(7,8-dihydro-7-benzyl-8-oxo-2-phenyl-9H-purin-9-yl) acetamide] synthesized by our laboratory, was used to evaluate the anxiolytic and antidepressant efficacy and to elucidate the underlying mechanisms. ZBD-2 (3 mg/kg) significantly attenuated anxiety-like and depressive behaviors in the UCMS mice, which was blocked by TSPO antagonist PK11195 (3 mg/kg). Treatment of ZBD-2 reversed the decrease in biogenic amines (norepinephrine, dopamine, and serotonin) in the brain region of hippocampus in the UCMS mice. The decreases in TSPO, GluN2B-containing N-methyl-D-aspartate (NMDA) receptors, GluA1, p-GluA1-Ser831, p-GluA1-Ser845, PSD-95, and GABAA-a2 were integrated with the increases of CaMKII and iNOS levels in the hippocampus of the UCMS mice. ZBD-2 significantly reversed the changes of above proteins. However, ZBD-2 or PK11195 treatment did not affect the levels of GluN2A-containing NMDA receptors and the total levels of GAD67. Our study provides strong evidences that ZBD-2 has a therapeutic effect on chronic stress-related disorders such as depression and anxiety through regulating the biogenic amine levels and the synaptic proteins in the hippocampus.
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Tetrapyrroles as Endogenous TSPO Ligands in Eukaryotes and Prokaryotes: Comparisons with Synthetic Ligands. Int J Mol Sci 2016; 17:ijms17060880. [PMID: 27271616 PMCID: PMC4926414 DOI: 10.3390/ijms17060880] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 05/17/2016] [Accepted: 05/19/2016] [Indexed: 12/26/2022] Open
Abstract
The 18 kDa translocator protein (TSPO) is highly 0conserved in eukaryotes and prokaryotes. Since its discovery in 1977, numerous studies established the TSPO’s importance for life essential functions. For these studies, synthetic TSPO ligands typically are applied. Tetrapyrroles present endogenous ligands for the TSPO. Tetrapyrroles are also evolutionarily conserved and regulate multiple functions. TSPO and tetrapyrroles regulate each other. In animals TSPO-tetrapyrrole interactions range from effects on embryonic development to metabolism, programmed cell death, response to stress, injury and disease, and even to life span extension. In animals TSPOs are primarily located in mitochondria. In plants TSPOs are also present in plastids, the nuclear fraction, the endoplasmic reticulum, and Golgi stacks. This may contribute to translocation of tetrapyrrole intermediates across organelles’ membranes. As in animals, plant TSPO binds heme and protoporphyrin IX. TSPO-tetrapyrrole interactions in plants appear to relate to development as well as stress conditions, including salt tolerance, abscisic acid-induced stress, reactive oxygen species homeostasis, and finally cell death regulation. In bacteria, TSPO is important for switching from aerobic to anaerobic metabolism, including the regulation of photosynthesis. As in mitochondria, in bacteria TSPO is located in the outer membrane. TSPO-tetrapyrrole interactions may be part of the establishment of the bacterial-eukaryote relationships, i.e., mitochondrial-eukaryote and plastid-plant endosymbiotic relationships.
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Nikou T, Ioannidis A, Zoga M, Tzavellas E, Paparrigopoulos T, Magana M, Pliatsika P, Nikolaou C, Chatzipanagiotou S. Alteration in the concentrations of Interleukin-7 (IL-7), Interleukin-10 (IL-10) and Granulocyte Colony Stimulating Factor (G-CSF) in alcohol-dependent individuals without liver disease, during detoxification therapy. Drug Alcohol Depend 2016; 163:77-83. [PMID: 27068251 DOI: 10.1016/j.drugalcdep.2016.03.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 03/17/2016] [Accepted: 03/28/2016] [Indexed: 12/23/2022]
Abstract
BACKGROUND The course of Interleukin-7 (IL-7), Interleukin-10 (IL-10) and Granulocyte Colony Stimulating Factor (G-CSF) was investigated in alcohol-dependent individuals without liver disease in order to ascertain the use of these cytokines as markers for the follow-up testing and the outcome of the detoxification treatment. METHODS Forty-eight alcohol-dependent individuals were admitted for alcohol detoxification. Blood was obtained upon admission, two weeks later and after the completion of the detoxification period (4-5 weeks). Serum IL-7, IL-10 and G-CSF were measured with a commercially available sandwich enzyme immunoassay. RESULTS IL-7 concentration was steadily high from admission up to two weeks later and then showed a fall, yet still remaining significantly higher than in the control group at the end of the detoxification treatment. IL-10 concentration was significantly low on admission, presenting a linear increase during therapy and remained insignificantly low at the end. G-CSF was significantly elevated on admission and presented a linear fall ending up in almost normal values at the end of the detoxification therapy. CONCLUSIONS The alterations in the concentration of IL-7, IL-10 and G-CSF and their trend to normalization during the detoxification therapy are indicative of the generalized immune system disorder, caused by alcohol abuse. Further studies will help in further elucidating the pathophysiology of the immune system function in alcohol abuse, while immunological parameters might serve as biological markers and diagnostic tools for the assessment of the course and the outcome of the detoxification therapy.
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Affiliation(s)
- Thomas Nikou
- Athens Medical School, Aeginition Hospital, Department of Psychiatry, National and Kapodistrian University of Athens, Greece
| | - Anastasios Ioannidis
- Department of Nursing, Faculty of Human Movement and Quality of Life Sciences, University of Peloponnese, Sparta, Greece; Athens Medical School, Aeginition Hospital, Department of Biopathology and Clinical Microbiology, National and Kapodistrian University of Athens, Greece
| | - Margarita Zoga
- Athens Medical School, Aeginition Hospital, Department of Biopathology and Clinical Microbiology, National and Kapodistrian University of Athens, Greece
| | - Elias Tzavellas
- Athens Medical School, Aeginition Hospital, Department of Psychiatry, National and Kapodistrian University of Athens, Greece
| | - Thomas Paparrigopoulos
- Athens Medical School, Aeginition Hospital, Department of Psychiatry, National and Kapodistrian University of Athens, Greece
| | - Maria Magana
- Athens Medical School, Aeginition Hospital, Department of Biopathology and Clinical Microbiology, National and Kapodistrian University of Athens, Greece
| | - Paraskevi Pliatsika
- Athens Medical School, Aeginition Hospital, Department of Biopathology and Clinical Microbiology, National and Kapodistrian University of Athens, Greece
| | - Chryssoula Nikolaou
- Athens Medical School, Aeginition Hospital, Department of Biopathology and Clinical Microbiology, National and Kapodistrian University of Athens, Greece
| | - Stylianos Chatzipanagiotou
- Athens Medical School, Aeginition Hospital, Department of Biopathology and Clinical Microbiology, National and Kapodistrian University of Athens, Greece.
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Shackebaei D, Feizollahi F, Hesari M, Bahrami G. The Effect of Diazepam on the Function of Hypertrophied Rats’ Hearts in Ischemia-Reperfusion Conditions. Int Cardiovasc Res J 2016. [DOI: 10.17795/icrj-10(2)89] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Zhang LM, Qiu ZK, Chen XF, Zhao N, Chen HX, Xue R, Zhang YZ, Yang RF, Li YF. Involvement of allopregnanolone in the anti-PTSD-like effects of AC-5216. J Psychopharmacol 2016; 30:474-81. [PMID: 26783231 DOI: 10.1177/0269881115625115] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cholesterol import into mitochondria through the translocator protein (18 KDa) (TSPO) is the starting point and an important rate-limiting step in neurosteroidogenesis. For this reason TSPO has received increased attention in the pathophysiology of post-traumatic stress disorder (PTSD). In an effort to explore the role of TSPO in mediating the anti-PTSD effect, we first assessed the effects of the TSPO ligand AC-5216 in alleviating the enhanced anxiety and fear response in a time-dependent sensitization (TDS) procedure, a rat PTSD animal model. In the present study, we showed that chronic treatment with AC-5216 caused significant suppression of the enhanced anxiety and contextual fear induced in post-TDS rats; these effects were blocked by PK11195. Furthermore, AC-5216 treatment increased the levels of allopregnanolone in the serum, prefrontal cortex, and hippocampus of post-TDS rats, and these effects were antagonized by PK11195. These results demonstrate that AC-5216 has a clear anti-PTSD-like effect, which might be partially mediated by binding to TSPO and the subsequent synthesis of allopregnanolone.
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Affiliation(s)
- Li-Ming Zhang
- Department of New Drug Evaluation, Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Zhi-Kun Qiu
- Department of New Drug Evaluation, Beijing Institute of Pharmacology and Toxicology, Beijing, China Department of Pharmacology, the First Affiliated Hospital, Guangdong Pharmaceutical University, Guangzhou, China
| | - Xiao-Fei Chen
- Department of Pharmacology, the 309 Hospital of PLA, Beijing, China
| | - Nan Zhao
- Department of New Drug Evaluation, Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Hong-Xia Chen
- Department of New Drug Evaluation, Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Rui- Xue
- Department of New Drug Evaluation, Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - You-Zhi Zhang
- Department of New Drug Evaluation, Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Ri-Fang Yang
- Department of Medicinal Chemistry, Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Yun-Feng Li
- Department of New Drug Evaluation, Beijing Institute of Pharmacology and Toxicology, Beijing, China
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Srivastava P, Kaul A, Ojha H, Kumar P, Tiwari AK. Design, synthesis and biological evaluation of methyl-2-(2-(5-bromo benzoxazolone)acetamido)-3-(1H-indol-3-yl)propanoate: TSPO ligand for SPECT. RSC Adv 2016. [DOI: 10.1039/c6ra19514h] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The translator protein (TSPO, 18 kDa), a transmembrane mitochondrial protein, has been explored as an important biomarker by researchers for inflammation, immune modulation and cell proliferation. Here we report a new SPECT agent99mTc-MBIP for TSPO imaging and quantification.
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Affiliation(s)
- Pooja Srivastava
- Division of Cyclotron and Radiopharmaceutical Sciences
- Institute of Nuclear Medicine and Allied Sciences
- Delhi-110054
- India
- Molecular Neuroscience and Functional Genomics Laboratory
| | - Ankur Kaul
- Division of Cyclotron and Radiopharmaceutical Sciences
- Institute of Nuclear Medicine and Allied Sciences
- Delhi-110054
- India
| | - Himanshu Ojha
- Division of Cyclotron and Radiopharmaceutical Sciences
- Institute of Nuclear Medicine and Allied Sciences
- Delhi-110054
- India
| | - Pravir Kumar
- Molecular Neuroscience and Functional Genomics Laboratory
- Department of Biotechnology
- Delhi Technological University
- Delhi 110042
- India
| | - Anjani K. Tiwari
- Division of Cyclotron and Radiopharmaceutical Sciences
- Institute of Nuclear Medicine and Allied Sciences
- Delhi-110054
- India
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Ramirez K, Niraula A, Sheridan JF. GABAergic modulation with classical benzodiazepines prevent stress-induced neuro-immune dysregulation and behavioral alterations. Brain Behav Immun 2016; 51:154-168. [PMID: 26342944 PMCID: PMC4679551 DOI: 10.1016/j.bbi.2015.08.011] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Revised: 07/31/2015] [Accepted: 08/10/2015] [Indexed: 12/30/2022] Open
Abstract
OBJECTIVE Psychosocial stress is associated with altered immunity, anxiety, and depression. Repeated social defeat (RSD), a model of social stress, triggers egress of inflammatory myeloid progenitor cells (MPCs; CD11b(+)/Ly6C(hi)) that traffic to the brain, promoting anxiety-like behavior. In parallel, RSD enhances neuroinflammatory signaling and long-lasting social avoidant behavior. Lorazepam and clonazepam are routinely prescribed anxiolytics that act by enhancing GABAergic activity in the brain. Besides binding to the central benzodiazepine binding site (CBBS) in the central nervous system (CNS), lorazepam binds to the translocator protein (TSPO) with high affinity causing immunomodulation. Clonazepam targets the CBBS and has low affinity for the TSPO. Here the aims were to determine if lorazepam and clonazepam would: (1) prevent stress-induced peripheral and central inflammatory responses, and (2) block anxiety and social avoidance behavior in mice subjected to RSD. METHODS C57/BL6 mice were divided into experimental groups, and treated with either lorazepam (0.10mg/kg), clonazepam (0.25mg/kg) or vehicle (0.9% NaCl). Behavioral data and tissues were collected the morning after the last cycle of RSD. RESULTS Lorazepam and clonazepam were effective in attenuating mRNA expression of CRH in the hypothalamus and corticosterone in plasma in mice subjected to RSD. Both drugs blocked stress-induced levels of IL-6 in plasma. Lorazepam and clonazepam had different effects on stress-induced enhancement of myelopoiesis and inhibited trafficking of monocytes and granulocytes in circulation. Furthermore, lorazepam, but not clonazepam, inhibited splenomegaly and the production of pro-inflammatory cytokines in the spleen following RSD. Additionally, lorazepam and clonazepam, blocked stress-induced accumulation of macrophages (CD11b(+)/CD45(high)) in the CNS. In a similar manner, both lorazepam and clonazepam prevented neuroinflammatory signaling and reversed anxiety-like and depressive-like behavior in mice exposed to RSD. CONCLUSION These data support the notion that lorazepam and clonazepam, aside from exerting anxiolytic and antidepressant effects, may have therapeutic potential as neuroimmunomodulators during psychosocial stress. The reversal of RSD-induced behavioral outcomes may be due to the enhancement of GABAergic neurotransmission, or some other off-target effect. The peripheral actions of lorazepam, but not clonazepam, seem to be mediated by TSPO activation.
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Affiliation(s)
- Karol Ramirez
- Division of Biosciences, The Ohio State University, College of Dentistry, Columbus, OH 43210, USA; Facultad de Odontología, Universidad de Costa Rica, San Pedro, San José 11501-2060, Costa Rica.
| | - Anzela Niraula
- Institute for Behavioral Medicine Research, The Ohio State University Medical Center, Columbus, OH 43210, USA; Department of Neuroscience, The Ohio State University, Columbus, OH 43212, USA.
| | - John F Sheridan
- Division of Biosciences, The Ohio State University, College of Dentistry, Columbus, OH 43210, USA; Department of Molecular Virology, Immunology and Medical Genetics, The Ohio State University Medical Center, Columbus, OH 43210, USA; Institute for Behavioral Medicine Research, The Ohio State University Medical Center, Columbus, OH 43210, USA.
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Morin D, Musman J, Pons S, Berdeaux A, Ghaleh B. Mitochondrial translocator protein (TSPO): From physiology to cardioprotection. Biochem Pharmacol 2015; 105:1-13. [PMID: 26688086 DOI: 10.1016/j.bcp.2015.12.003] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Accepted: 12/04/2015] [Indexed: 01/08/2023]
Abstract
The mitochondrial translocator protein (TSPO) is a high affinity cholesterol binding protein which is primarily located in the outer mitochondrial membrane where it has been shown to interact with proteins implicated in mitochondrial permeability transition pore (mPTP) formation. TSPO is found in different species and is expressed at high levels in tissues that synthesize steroids but is also present in other peripheral tissues especially in the heart. TSPO has been involved in the import of cholesterol into mitochondria, a key step in steroidogenesis. This constitutes the main established function of the protein which was recently challenged by genetic studies. TSPO has also been associated directly or indirectly with a wide range of cellular functions such as apoptosis, cell proliferation, differentiation, regulation of mitochondrial function or porphyrin transport. In the heart the role of TSPO remains undefined but a growing body of evidence suggests that TSPO plays a critical role in regulating physiological cardiac function and that TSPO ligands may represent interesting drugs to protect the heart under pathological conditions. This article briefly reviews current knowledge regarding TSPO and discusses its role in the cardiovascular system under physiological and pathologic conditions. More particularly, it provides evidence that TSPO can represent an alternative strategy to develop new pharmacological agents to protect the myocardium against ischemia-reperfusion injury.
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Affiliation(s)
- Didier Morin
- INSERM U955, Équipe 3, Créteil, France; Université Paris-Est, UMR_S955, DHU A-TVB, UPEC, Créteil, France.
| | - Julien Musman
- INSERM U955, Équipe 3, Créteil, France; Université Paris-Est, UMR_S955, DHU A-TVB, UPEC, Créteil, France.
| | - Sandrine Pons
- INSERM U955, Équipe 3, Créteil, France; Université Paris-Est, UMR_S955, DHU A-TVB, UPEC, Créteil, France.
| | - Alain Berdeaux
- INSERM U955, Équipe 3, Créteil, France; Université Paris-Est, UMR_S955, DHU A-TVB, UPEC, Créteil, France.
| | - Bijan Ghaleh
- INSERM U955, Équipe 3, Créteil, France; Université Paris-Est, UMR_S955, DHU A-TVB, UPEC, Créteil, France.
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Vainshtein A, Veenman L, Shterenberg A, Singh S, Masarwa A, Dutta B, Island B, Tsoglin E, Levin E, Leschiner S, Maniv I, Pe’er L, Otradnov I, Zubedat S, Aga-Mizrachi S, Weizman A, Avital A, Marek I, Gavish M. Quinazoline-based tricyclic compounds that regulate programmed cell death, induce neuronal differentiation, and are curative in animal models for excitotoxicity and hereditary brain disease. Cell Death Discov 2015; 1:15027. [PMID: 27551459 PMCID: PMC4979516 DOI: 10.1038/cddiscovery.2015.27] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 07/16/2015] [Indexed: 12/21/2022] Open
Abstract
Expanding on a quinazoline scaffold, we developed tricyclic compounds with biological activity. These compounds bind to the 18 kDa translocator protein (TSPO) and protect U118MG (glioblastoma cell line of glial origin) cells from glutamate-induced cell death. Fascinating, they can induce neuronal differentiation of PC12 cells (cell line of pheochromocytoma origin with neuronal characteristics) known to display neuronal characteristics, including outgrowth of neurites, tubulin expression, and NeuN (antigen known as 'neuronal nuclei', also known as Rbfox3) expression. As part of the neurodifferentiation process, they can amplify cell death induced by glutamate. Interestingly, the compound 2-phenylquinazolin-4-yl dimethylcarbamate (MGV-1) can induce expansive neurite sprouting on its own and also in synergy with nerve growth factor and with glutamate. Glycine is not required, indicating that N-methyl-D-aspartate receptors are not involved in this activity. These diverse effects on cells of glial origin and on cells with neuronal characteristics induced in culture by this one compound, MGV-1, as reported in this article, mimic the diverse events that take place during embryonic development of the brain (maintenance of glial integrity, differentiation of progenitor cells to mature neurons, and weeding out of non-differentiating progenitor cells). Such mechanisms are also important for protective, curative, and restorative processes that occur during and after brain injury and brain disease. Indeed, we found in a rat model of systemic kainic acid injection that MGV-1 can prevent seizures, counteract the process of ongoing brain damage, including edema, and restore behavior defects to normal patterns. Furthermore, in the R6-2 (transgenic mouse model for Huntington disease; Strain name: B6CBA-Tg(HDexon1)62Gpb/3J) transgenic mouse model for Huntington disease, derivatives of MGV-1 can increase lifespan by >20% and reduce incidence of abnormal movements. Also in vitro, these derivatives were more effective than MGV-1.
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Affiliation(s)
- A Vainshtein
- Department of Neuroscience, Technion – Israel Institute of Technology, Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences, Haifa, Israel
| | - L Veenman
- Department of Neuroscience, Technion – Israel Institute of Technology, Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences, Haifa, Israel
| | - A Shterenberg
- Technion – Israel Institute of Technology, Schulich Faculty of Chemistry, The Mallat Family Laboratory of Organic Chemistry, Haifa, Israel
| | - S Singh
- Technion – Israel Institute of Technology, Schulich Faculty of Chemistry, The Mallat Family Laboratory of Organic Chemistry, Haifa, Israel
| | - A Masarwa
- Technion – Israel Institute of Technology, Schulich Faculty of Chemistry, The Mallat Family Laboratory of Organic Chemistry, Haifa, Israel
| | - B Dutta
- Technion – Israel Institute of Technology, Schulich Faculty of Chemistry, The Mallat Family Laboratory of Organic Chemistry, Haifa, Israel
| | - B Island
- Technion – Israel Institute of Technology, Schulich Faculty of Chemistry, The Mallat Family Laboratory of Organic Chemistry, Haifa, Israel
| | - E Tsoglin
- Technion – Israel Institute of Technology, Schulich Faculty of Chemistry, The Mallat Family Laboratory of Organic Chemistry, Haifa, Israel
| | - E Levin
- Department of Neuroscience, Technion – Israel Institute of Technology, Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences, Haifa, Israel
| | - S Leschiner
- Department of Neuroscience, Technion – Israel Institute of Technology, Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences, Haifa, Israel
| | - I Maniv
- Department of Neuroscience, Technion – Israel Institute of Technology, Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences, Haifa, Israel
| | - L Pe’er
- Department of Neuroscience, Technion – Israel Institute of Technology, Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences, Haifa, Israel
| | - I Otradnov
- Department of Neuroscience, Technion – Israel Institute of Technology, Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences, Haifa, Israel
| | - S Zubedat
- Department of Physiology, Technion – Israel Institute of Technology, The Behavioral Neuroscience Laboratory, Faculty of Medicine and Emek Medical Center, Haifa, Israel
| | - S Aga-Mizrachi
- Department of Physiology, Technion – Israel Institute of Technology, The Behavioral Neuroscience Laboratory, Faculty of Medicine and Emek Medical Center, Haifa, Israel
| | - A Weizman
- Tel Aviv University, Sackler Faculty of Medicine, The Felsenstein Medical Research Center, Geha Mental Health Center, Tel Aviv, Israel
| | - A Avital
- Department of Physiology, Technion – Israel Institute of Technology, The Behavioral Neuroscience Laboratory, Faculty of Medicine and Emek Medical Center, Haifa, Israel
| | - I Marek
- Technion – Israel Institute of Technology, Schulich Faculty of Chemistry, The Mallat Family Laboratory of Organic Chemistry, Haifa, Israel
| | - M Gavish
- Department of Neuroscience, Technion – Israel Institute of Technology, Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences, Haifa, Israel
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Veenman L, Vainshtein A, Gavish M. TSPO as a target for treatments of diseases, including neuropathological disorders. Cell Death Dis 2015; 6:e1911. [PMID: 26469960 PMCID: PMC4632315 DOI: 10.1038/cddis.2015.294] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- L Veenman
- Department of Neuroscience, Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences, Technion – Israel Institute of Technology, Haifa, Israel
| | - A Vainshtein
- Department of Neuroscience, Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences, Technion – Israel Institute of Technology, Haifa, Israel
| | - M Gavish
- Department of Neuroscience, Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences, Technion – Israel Institute of Technology, Haifa, Israel
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Abstract
Suvorexant is a novel dual orexin receptor antagonist (DORA) newly introduced in the U.S. as a hypnotic, but no claim of superiority over other hypnotics has been offered. The manufacturer argued that the 5 and 10 mg starting doses recommended by the FDA might be ineffective. The manufacturer's main Phase III trials had not even included the 10 mg dosage, and the 5 mg dosage had not been tested at all in registered clinical trials at the time of approval. Popular alternative hypnotics may be similarly ineffective, since the FDA has also reduced the recommended doses for zolpidem and eszopiclone. The "not to exceed" suvorexant dosage of 20 mg does slightly increase sleep. Because of slow absorption, suvorexant has little effect on latency to sleep onset but some small effect in suppressing wakening after sleep onset and in improving sleep efficiency. The FDA would not approve the manufacturer's preferred 40 mg suvorexant dosage, because of concern with daytime somnolence, driving impairment, and possible narcolepsy-like symptoms. In its immediate benefits-to-risks ratio, suvorexant is unlikely to prove superior to currently available hypnotics—possibly worse—so there is little reason to prefer over the alternatives this likely more expensive hypnotic less-tested in practice. Associations are being increasingly documented relating hypnotic usage with incident cancer, with dementia risks, and with premature death. There is some basis to speculate that suvorexant might be safer than alternative hypnotics in terms of cancer, dementia, infections, and mortality. These safety considerations will remain unproven speculations unless adequate long-term trials can be done that demonstrate suvorexant advantages.
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Affiliation(s)
- Daniel F Kripke
- Scripps Clinic Viterbi Family Sleep Center, La Jolla, CA, USA
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69
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Papadopoulos V, Aghazadeh Y, Fan J, Campioli E, Zirkin B, Midzak A. Translocator protein-mediated pharmacology of cholesterol transport and steroidogenesis. Mol Cell Endocrinol 2015; 408:90-8. [PMID: 25818881 PMCID: PMC4417383 DOI: 10.1016/j.mce.2015.03.014] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 03/16/2015] [Accepted: 03/17/2015] [Indexed: 12/17/2022]
Abstract
Steroidogenesis begins with cholesterol transfer into mitochondria through the transduceosome, a complex composed of cytosolic proteins that include steroidogenesis acute regulatory protein (STAR), 14-3-3 adaptor proteins, and the outer mitochondrial membrane proteins Translocator Protein (TSPO) and Voltage-Dependent Anion Channel (VDAC). TSPO is a drug- and cholesterol-binding protein found at particularly high levels in steroid synthesizing cells. Its aberrant expression has been linked to cancer, neurodegeneration, neuropsychiatric disorders and primary hypogonadism. Brain steroids serve as local regulators of neural development and excitability. Reduced levels of these steroids have been linked to depression, anxiety and neurodegeneration. Reduced serum testosterone is common among subfertile young men and aging men, and is associated with depression, metabolic syndrome and reduced sexual function. Although testosterone-replacement therapy is available, there are undesired side-effects. TSPO drug ligands have been proposed as therapeutic agents to regulate steroid levels in the brain and testis.
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Affiliation(s)
- Vassilios Papadopoulos
- The Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada; Department of Medicine, McGill University, Montreal, Quebec, Canada; Department of Pharmacology & Therapeutics, McGill University, Montreal, Quebec, Canada; Departments of Biochemistry, McGill University, Montreal, Quebec, Canada.
| | - Yasaman Aghazadeh
- The Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada; Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Jinjiang Fan
- The Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada; Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Enrico Campioli
- The Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada; Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Barry Zirkin
- Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, USA
| | - Andrew Midzak
- The Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada; Departments of Biochemistry, McGill University, Montreal, Quebec, Canada
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The mitochondrial translocator protein and arrhythmogenesis in ischemic heart disease. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2015:234104. [PMID: 25918579 PMCID: PMC4397036 DOI: 10.1155/2015/234104] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 03/18/2015] [Indexed: 12/19/2022]
Abstract
Mitochondrial dysfunction is a hallmark of multiple cardiovascular disorders, including ischemic heart disease. Although mitochondria are well recognized for their role in energy production and cell death, mechanisms by which they control excitation-contraction coupling, excitability, and arrhythmias are less clear. The translocator protein (TSPO) is an outer mitochondrial membrane protein that is expressed in multiple organ systems. The abundant expression of TSPO in macrophages has been leveraged to image the immune response of the heart to inflammatory processes. More recently, the recognition of TSPO as a regulator of energy-dissipating mitochondrial pathways has extended its utility from a diagnostic marker of inflammation to a therapeutic target influencing diverse pathophysiological processes. Here, we provide an overview of the emerging role of TSPO in ischemic heart disease. We highlight the importance of TSPO in the regenerative process of reactive oxygen species (ROS) induced ROS release through its effects on the inner membrane anion channel (IMAC) and the permeability transition pore (PTP). We discuss evidence implicating TSPO in arrhythmogenesis in the settings of acute ischemia-reperfusion injury and myocardial infarction.
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71
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Zhang L, Yang L. Anti-inflammatory effects of vinpocetine in atherosclerosis and ischemic stroke: a review of the literature. Molecules 2014; 20:335-47. [PMID: 25549058 PMCID: PMC6272149 DOI: 10.3390/molecules20010335] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 12/19/2014] [Indexed: 12/21/2022] Open
Abstract
Immune responses play an important role in the pathophysiology of atherosclerosis and ischemic stroke. Atherosclerosis is a common condition that increases the risk of stroke. Hyperlipidemia damages endothelial cells, thus initiating chemokine pathways and the release of inflammatory cytokines—this represents the first step in the inflammatory response to atherosclerosis. Blocking blood flow in the brain leads to ischemic stroke, and deprives neurons of oxygen and energy. Damaged neurons release danger-associated molecular patterns, which promote the activation of innate immune cells and the release of inflammatory cytokines. The nuclear factor κ-light-chain-enhancer of activated B cells κB (NF-κB) pathway plays a key role in the pathogenesis of atherosclerosis and ischemic stroke. Vinpocetine is believed to be a potent anti-inflammatory agent and has been used to treat cerebrovascular disorders. Vinpocetine improves neuronal plasticity and reduces the release of inflammatory cytokines and chemokines from endothelial cells, vascular smooth muscle cells, macrophages, and microglia, by inhibiting the inhibitor of the NF-κB pathway. This review clarifies the anti-inflammatory role of vinpocetine in atherosclerosis and ischemic stroke.
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Clavier T, Tonon MC, Foutel A, Besnier E, Lefevre-Scelles A, Morin F, Gandolfo P, Tuech JJ, Quillard M, Veber B, Dureuil B, Castel H, Compère V. Increased plasma levels of endozepines, endogenous ligands of benzodiazepine receptors, during systemic inflammation: a prospective observational study. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2014; 18:633. [PMID: 25407756 PMCID: PMC4326502 DOI: 10.1186/s13054-014-0633-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 10/31/2014] [Indexed: 12/30/2022]
Abstract
Introduction Recent work has shown that benzodiazepines interact with the immune system and exhibit anti-inflammatory effects. By using in vitro models, researchers in several studies have shown that the peptidergic endogenous ligands of benzodiazepine receptors, named endozepines, are involved in the immune response. All endozepines identified so far derive from diazepam-binding inhibitor (DBI), which generates several biologically active fragments. The aim of the present study was to measure plasma levels of DBI-like immunoreactivity (DBI-LI) in a rat model of sepsis and in patients with systemic inflammation from septic or non-septic origin. Methods Cecal ligation and puncture (CLP) or sham surgery was performed in rats. Blood samples were taken from animals, patients hospitalized for digestive surgery with inflammatory diseases, and healthy volunteers. Measurements of plasma DBI-related peptides were carried out by radioimmunoassay in animal and human samples. Results In the rats, CLP provoked an increase of plasma DBI-LI (+37%) 6 hours postsurgery. In humans, DBI-LI levels were significantly higher in the systemic inflammation group than in the healthy volunteer group (48.6 (32.7 to 77.7) pg/ml versus 11.1 (5.9 to 35.3) pg/ml, P < 0.001). We found a positive correlation between endozepine levels and Acute Physiology and Chronic Health Evaluation II score (rs = 0.33 (0.026 to 0.58), P < 0.05) and tumor necrosis factor α levels (rs = 0.43 (0.14 to 0.65), P < 0.01). The area under the receiver operating characteristic curve for endozepines was 0.842 (95% CI (0.717 to 0.966), P < 0.0001) for discriminating patients with inflammation from healthy volunteers. Conclusions Endozepines might be involved in the inflammatory response in patients with systemic inflammation.
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Affiliation(s)
- Thomas Clavier
- Institut National de la Santé et de la Recherche Médicale (Inserm), U982, Place Emile Blondel, 76130, Mont-Saint-Aignan, France. .,Normandy University, Institute for Research and Innovation in Biomedicine (IRIB), Place Emile Blondel, 76130, Mont-Saint-Aignan, France. .,Rouen University, Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Place Emile Blondel, 76130, Mont-Saint-Aignan, France. .,Department of Anesthesiology and Critical Care, Rouen University Hospital, Rue de Germont, 76000, Rouen, France.
| | - Marie-Christine Tonon
- Institut National de la Santé et de la Recherche Médicale (Inserm), U982, Place Emile Blondel, 76130, Mont-Saint-Aignan, France. .,Normandy University, Institute for Research and Innovation in Biomedicine (IRIB), Place Emile Blondel, 76130, Mont-Saint-Aignan, France. .,Rouen University, Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Place Emile Blondel, 76130, Mont-Saint-Aignan, France.
| | - Anne Foutel
- Department of Anesthesiology and Critical Care, Rouen University Hospital, Rue de Germont, 76000, Rouen, France.
| | - Emmanuel Besnier
- Institut National de la Santé et de la Recherche Médicale (Inserm), U982, Place Emile Blondel, 76130, Mont-Saint-Aignan, France. .,Normandy University, Institute for Research and Innovation in Biomedicine (IRIB), Place Emile Blondel, 76130, Mont-Saint-Aignan, France. .,Rouen University, Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Place Emile Blondel, 76130, Mont-Saint-Aignan, France. .,Department of Anesthesiology and Critical Care, Rouen University Hospital, Rue de Germont, 76000, Rouen, France.
| | - Antoine Lefevre-Scelles
- Department of Anesthesiology and Critical Care, Rouen University Hospital, Rue de Germont, 76000, Rouen, France.
| | - Fabrice Morin
- Institut National de la Santé et de la Recherche Médicale (Inserm), U982, Place Emile Blondel, 76130, Mont-Saint-Aignan, France. .,Normandy University, Institute for Research and Innovation in Biomedicine (IRIB), Place Emile Blondel, 76130, Mont-Saint-Aignan, France. .,Rouen University, Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Place Emile Blondel, 76130, Mont-Saint-Aignan, France.
| | - Pierrick Gandolfo
- Institut National de la Santé et de la Recherche Médicale (Inserm), U982, Place Emile Blondel, 76130, Mont-Saint-Aignan, France. .,Normandy University, Institute for Research and Innovation in Biomedicine (IRIB), Place Emile Blondel, 76130, Mont-Saint-Aignan, France. .,Rouen University, Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Place Emile Blondel, 76130, Mont-Saint-Aignan, France.
| | - Jean-Jacques Tuech
- Department of Digestive Surgery, Rouen University Hospital, Rue de Germont, 76000, Rouen, France.
| | - Muriel Quillard
- Department of Medical Biochemistry, Institute of Clinical Biology, Rouen University Hospital, 76000, Rouen, France.
| | - Benoit Veber
- Department of Anesthesiology and Critical Care, Rouen University Hospital, Rue de Germont, 76000, Rouen, France.
| | - Bertrand Dureuil
- Department of Anesthesiology and Critical Care, Rouen University Hospital, Rue de Germont, 76000, Rouen, France.
| | - Hélène Castel
- Institut National de la Santé et de la Recherche Médicale (Inserm), U982, Place Emile Blondel, 76130, Mont-Saint-Aignan, France. .,Normandy University, Institute for Research and Innovation in Biomedicine (IRIB), Place Emile Blondel, 76130, Mont-Saint-Aignan, France. .,Rouen University, Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Place Emile Blondel, 76130, Mont-Saint-Aignan, France.
| | - Vincent Compère
- Institut National de la Santé et de la Recherche Médicale (Inserm), U982, Place Emile Blondel, 76130, Mont-Saint-Aignan, France. .,Normandy University, Institute for Research and Innovation in Biomedicine (IRIB), Place Emile Blondel, 76130, Mont-Saint-Aignan, France. .,Rouen University, Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Place Emile Blondel, 76130, Mont-Saint-Aignan, France. .,Department of Anesthesiology and Critical Care, Rouen University Hospital, Rue de Germont, 76000, Rouen, France.
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Anxiolytic-like effects of YL-IPA08, a potent ligand for the translocator protein (18 kDa) in animal models of post-traumatic stress disorder. Int J Neuropsychopharmacol 2014; 17:1659-69. [PMID: 24763106 DOI: 10.1017/s1461145714000479] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Recently, the translocator protein (18 kDa) (TSPO), previously called peripheral benzodiazepine receptor (PBR) and both the starting point and an important rate-limiting step in neurosteroidogenesis, has received increased attention in the pathophysiology of post-traumatic stress disorder (PTSD) because it affects the production of neurosteroids, reinforcing the hypothesis that selective TSPO ligands could potentially be used as anti-PTSD drugs. As expected, we showed that chronic treatment with YL-IPA08 [N-ethyl-N-(2-pyridinylmethyl)-2-(3,4-ichlorophenyl)-7-methylimidazo [1,2-a] pyridine-3-acetamide hydrochloride], a potent and selective TSPO ligand synthesized by our institute, caused significant suppression of enhanced anxiety and contextual fear induced in the inescapable electric foot-shock-induced mouse model of PTSD and the time-dependent sensitization (TDS) procedure. These effects were completely blocked by the TSPO antagonist PK11195. Furthermore, YL-IPA08 could increase the level of allopregnanolone in the prefrontal cortex and serum of post-TDS rats, and these effects were antagonized by PK11195. In summary, the findings from the current study showed that YL-IPA08, a potent and selective TSPO ligand, had a clear anti-PTSD-like effect, which might be partially mediated by binding to TSPO and the subsequent synthesis of allopregnanolone.
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Advances in mechanisms, imaging and management of the unstable plaque. Atherosclerosis 2014; 233:467-477. [PMID: 24530781 DOI: 10.1016/j.atherosclerosis.2014.01.036] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 01/14/2014] [Accepted: 01/15/2014] [Indexed: 01/09/2023]
Abstract
Post-mortem observations demonstrated that plaque fissure was the final event leading to coronary thrombosis and occlusion in about two-thirds of cases of sudden coronary death. Plaques prone to fissure have, therefore, been defined "vulnerable plaques" and are identified by specific anatomic features including thin inflamed fibrous cap, large lipidic core and positive remodeling. Accordingly, elegant imaging modalities have been developed in order to identify this "holy grail". However, the results of prognostic studies based on the identification of vulnerable plaques have not been encouraging because of the low positive predictive value for major cardiovascular events. This observation is not surprising as the pathogenesis of acute coronary syndromes is complex and multifactorial. In this review we propose a pathogenetic classification of acute coronary syndromes in the attempt to identify homogeneous groups of patients with a common mechanism of coronary instability which can be identified by using specific biomarkers and imaging techniques, and become a specific therapeutic target.
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Fairweather D, Coronado MJ, Garton AE, Dziedzic JL, Bucek A, Cooper LT, Brandt JE, Alikhan FS, Wang H, Endres CJ, Choi J, Pomper MG, Guilarte TR. Sex differences in translocator protein 18 kDa (TSPO) in the heart: implications for imaging myocardial inflammation. J Cardiovasc Transl Res 2014; 7:192-202. [PMID: 24402571 DOI: 10.1007/s12265-013-9538-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 12/18/2013] [Indexed: 12/17/2022]
Abstract
Myocarditis is more severe in men than in women and difficult to diagnose due to a lack of imaging modalities that directly detect myocardial inflammation. Translocator protein 18 kDa (TSPO) is used extensively to image brain inflammation due to its presence in CD11b(+) brain microglia. In this study, we examined expression of TSPO and CD11b in mice with coxsackievirus B3 (CVB3) myocarditis and biopsy sections from myocarditis patients in order to determine if it could be used to image myocarditis. We found that male mice with CVB3 myocarditis upregulated more genes associated with TSPO activation than female mice. TSPO expression was increased in the heart of male mice and men with myocarditis compared with female subjects due to testosterone, where it was expressed predominantly in CD11b(+) immune cells. We show that TSPO ligands detect myocardial inflammation using microSPECT, with increased uptake of [(125)I]-IodoDPA-713 in male mice with CVB3 myocarditis compared with undiseased controls.
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Affiliation(s)
- DeLisa Fairweather
- Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Baltimore, MD, 21205, USA,
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76
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Lecanu L, Yao ZX, McCourty A, Sidahmed EK, Orellana ME, Burnier MN, Papadopoulos V. Control of hypercholesterolemia and atherosclerosis using the cholesterol recognition/interaction amino acid sequence of the translocator protein TSPO. Steroids 2013; 78. [PMID: 23182766 PMCID: PMC3552137 DOI: 10.1016/j.steroids.2012.10.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The translocator protein (18-kDa) TSPO is an ubiquitous high affinity cholesterol-binding protein reported to be present in the endothelial and smooth muscle cells of the blood vessels; its expression dramatically increased in macrophages found in atherosclerotic plaques. A domain in the carboxy-terminus of TSPO was identified and characterized as the cholesterol recognition/interaction amino acid consensus (CRAC). The ability of the CRAC domain to bind to cholesterol led us to hypothesize that this peptide could be used as an hypocholesterolemic, with potential anti-atherogenic properties, agent. We report herein the therapeutic benefit that resulted for the administration of the VLNYYVWR human CRAC sequence to guinea pigs fed with a high cholesterol diet and ApoE knock-out B6.129P2-Apoetm1Unc/J mice. CRAC treatment (3 and 30mg/kg once daily for 6 weeks) resulted in reduced circulating cholesterol levels in guinea pigs fed with 2% high cholesterol diet and ApoE knock-out B6.129P2-Apoetm1Unc/J mice. In high cholesterol fed guinea pigs, CRAC treatment administered once daily induced an increase in circulating HDL, decreased total, free and LDL cholesterol, and removed atheroma deposits in the aorta in a dose-dependent manner. The treatment also prevented the high cholesterol diet-induced increase in serum creatine kinase, total and isoforms, markers of neurological, cardiac and muscular damage. No toxicity was observed. Taken together these results support a role of TSPO in lipid homeostasis and atherosclerosis and indicate that CRAC may constitute a novel and safe treatment of hypercholesterolemia and atherosclerosis.
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Affiliation(s)
- Laurent Lecanu
- The Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
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77
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Effects of 18-kDa translocator protein knockdown on gene expression of glutamate receptors, transporters, and metabolism, and on cell viability affected by glutamate. Pharmacogenet Genomics 2012; 22:606-19. [PMID: 22732722 DOI: 10.1097/fpc.0b013e3283544531] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE Previously, several important roles for glutamate have been described for the biology of primary brain tumors. For example, glutamate has been suggested to promote glioma cell proliferation by the activation of the 2-amino-3-(5-methyl-3-oxo-1,2-oxazol-4-yl)propanoic acid (AMPA) subtype of glutamate receptors. In the present study, we determined the potential regulatory roles of the 18-kDa translocator protein (TSPO) in the glutamatergic system in relation to cell death of brain tumor cells through knockdown of the TSPO by genetic manipulation. MATERIALS AND METHODS With microarray analysis and validation of gene expression of particular genes using real-time PCR, we found effects because of small inhibitory RNA knockdown of the TSPO in human U118MG glioblastoma cells on gene expression of glutamate receptors, glutamate transporters, and enzymes for glutamate metabolism. We also applied antisense RNA to silence TSPO in rat C6 glioblastoma cells and assayed the effects on DNA fragmentation, indicative of apoptosis, because of glutamate exposure. RESULTS In particular, the effects of TSPO silencing in human U118MG cells related to glutamate metabolism indicate a net effect of a reduction in glutamate levels, which may potentially protect the cells in question from cell death. The TSPO knockdown in C6 cells showed that TSPO is required for the induction of apoptosis because of glutamate exposure. CONCLUSION These findings show that interactions between the TSPO and the glutamatergic system may play a role in tumor development of glioblastoma cells. This may also have implications for our understanding of the involvement of the TSPO in secondary brain damage and neurodegenerative diseases.
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Shargorodsky L, Veenman L, Caballero B, Pe'er Y, Leschiner S, Bode J, Gavish M. The nitric oxide donor sodium nitroprusside requires the 18 kDa Translocator Protein to induce cell death. Apoptosis 2012; 17:647-65. [PMID: 22544277 DOI: 10.1007/s10495-012-0725-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Various studies have shown that several lethal agents induce cell death via the mitochondrial 18 kDa Translocator Protein (TSPO). In this study we tested the possibility that nitric oxide (NO) is the signaling component inducing the TSPO to initiate cell death process. Cell viability assays included Trypan blue uptake, propidium iodide uptake, lactate dehydrogenase release, and DNA fragmentation. These assays showed that application of the specific TSPO ligand PK 11195 reduced these parameters for the lethal effects of the NO donor sodium nitroprusside (SNP) by 41, 27, 40, and 42 %, respectively. TSPO silencing by siRNA also reduced the measured lethal effects of SNP by 50 % for all of these four assays. With 2,3-bis[2-methoxy-4-nitro-5-sulphophenyl]-2H-tetrazolium-5-carboxyanilide (XTT) changes in metabolic activity were detected. PK 11195 and TSPO knockdown fully prevented the reductions in XTT signal otherwise induced by SNP. Collapse of the mitochondrial membrane potential was studied with the aid of JC-1 (5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-benzimidazolylcarbocyanine chloride). PK 11195 and TSPO knockdown reduced, respectively by 36 and 100 %, the incidence of collapse of the mitochondrial membrane potential otherwise induced by SNP. 10-N-Nonyl-Acridine Orange (NAO) was used to detect mitochondrial reactive oxygen species generation due to SNP. PK 11195 and TSPO knockdown reduced this effect of SNP by 65 and 100 %, respectively. SNP did not affect TSPO protein expression and binding characteristics, and also did not cause TSPO S-nitrosylation. However, β-actin and various other proteins (not further defined) were S-nitrosylated. In conclusion, TSPO is required for the lethal and metabolic effects of the NO donor SNP, but TSPO itself is not S-nitrosylated.
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Affiliation(s)
- Luba Shargorodsky
- Department of Molecular Pharmacology, Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences, Technion-Israel Institute of Technology, Haifa, Israel
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79
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Translocator protein (18 kDa): a promising therapeutic target and diagnostic tool for cardiovascular diseases. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2012; 2012:162934. [PMID: 23251719 PMCID: PMC3516045 DOI: 10.1155/2012/162934] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Revised: 10/22/2012] [Accepted: 11/04/2012] [Indexed: 01/15/2023]
Abstract
The translocator protein (18 kDa) (TSPO) is a five transmembrane domain protein in mitochondria, abundantly expressed in a variety of organs and tissues. TSPO contributes to a wide range of biological processes, including cholesterol transportation, mitochondrial membrane potential and respiratory chain regulation, apoptosis, and oxidative stress. Recent studies have demonstrated that TSPO might also be involved in the physiological regulation of cardiac chronotropy and inotropy. Accordingly, TSPO ligands play significant roles in protecting the cardiovascular systems under pathological conditions through cardiac electrical activity retention, intracellular calcium maintenance, mitochondrial energy provision, mitochondrial membrane potential equilibrium, and reactive oxygen species inhibition. This paper focuses on the physiological and pathological characteristics of TSPO in the cardiovascular systems and also summarizes the properties of TSPO ligands. TSPO represents a potential therapeutic target and diagnostic tool for cardiovascular diseases including arrhythmia, myocardial infarction, cardiac hypertrophy, atherosclerosis, myocarditis, and large vessel vasculitis.
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80
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Xie L, Yui J, Hatori A, Yamasaki T, Kumata K, Wakizaka H, Yoshida Y, Fujinaga M, Kawamura K, Zhang MR. Translocator protein (18 kDa), a potential molecular imaging biomarker for non-invasively distinguishing non-alcoholic fatty liver disease. J Hepatol 2012; 57:1076-82. [PMID: 22796156 DOI: 10.1016/j.jhep.2012.07.002] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2012] [Revised: 06/29/2012] [Accepted: 07/02/2012] [Indexed: 12/20/2022]
Abstract
BACKGROUND & AIMS Mitochondrial dysfunction is responsible for liver damage and disease progression in non-alcoholic fatty liver disease (NAFLD). Translocator protein (18 kDa) (TSPO), a mitochondrial transmembrane protein, plays important roles in modulating mitochondrial function. This study explored whether TSPO can be used as an imaging biomarker of non-invasive diagnosis and staging of NAFLD, monitored using positron emission tomography (PET) with a TSPO radioligand [(18)F]FEDAC. METHODS PET with [(18)F]FEDAC, non-enhanced computerized tomography (CT), autoradiography, histopathology, and gene analysis were performed to evaluate and quantify TSPO levels and NAFLD progression in methionine and choline-deficient diet-fed mice. Correlations were analyzed between uptake ratio of radioactivity and NAFLD activity score (NAS) in the liver. RESULTS Uptake of [(18)F]FEDAC obviously increased with disease progression from simple steatosis to non-alcoholic steatohepatitis (NASH) (p<0.01). A close correlation was identified between [(18)F]FEDAC uptake ratio and NAS in the liver (Pearson's r=0.922, p=0.000). Specific binding of [(18)F]FEDAC to TSPO in the NAFLD livers was assessed in competition studies with the unlabelled TSPO-selective ligand PK11195. Autoradiography and histopathology confirmed the PET imaging results. Further, the mRNA levels of the functional macromolecular signaling complex composed of TSPO were obviously higher compared to controls. CONCLUSIONS TSPO expression increases in NAFLD and closely correlates with NAFLD progression. TSPO as a specific molecular imaging biomarker may open a novel avenue for non-invasive, reliable, and quantitative diagnosis and staging of NAFLD.
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Affiliation(s)
- Lin Xie
- Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
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81
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Kaynar G, Yurdakan G, Comert F, Yilmaz-Sipahi E. Effects of peripheral benzodiazepine receptor ligand Ro5-4864 in four animal models of acute lung injury. J Surg Res 2012; 182:277-84. [PMID: 23127280 DOI: 10.1016/j.jss.2012.10.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Revised: 10/01/2012] [Accepted: 10/12/2012] [Indexed: 10/27/2022]
Abstract
BACKGROUND Acute lung injury (ALI) is a syndrome of inflammation and increased permeability of the blood-gas barrier. It is associated with high morbidity and mortality. Despite intensive research, treatments remain limited. The aim of the present study was to investigate the protective efficacy of a specific peripheral benzodiazepine receptor ligand, Ro5-4864, in experimental models of ALI in rats. METHODS ALI was generated by four different methods: (1) intravenous (tail vein) injection of Escherichia coli (0111:B4) lipopolysaccaride (LPS), (2) cecal ligation and puncture (CLP), (3) mesenteric ischemia/reperfusion, and (4) intraperitoneal injection of α-naphthylthiourea (ANTU). Ro5-4864 was administered to rats intraperitoneally 30 min before ANTU and LPS administration or intravenously 15 min before reperfusion and CLP. The levels of pulmonary edema (lung weight/body weight ratio) and pleural effusion were measured, and the severity of ALI was scored (0-3). RESULTS Ro5-4864 showed a dose-dependent and significant prophylactic effect on the ANTU-induced lung weight/body weight and pleural effusion/body weight ratios and histopathologic scores. Ro5-4864 also showed significant prophylactic effects against the LPS-induced lung weight/body weight ratio and histopathologic scores. Ro5-4864 significantly decreased the intra-alveolar edema and perialveolar hemorrhage scores in the CLP group. However, we found no prophylactic effect of Ro5-4864 on mesenteric ischemia/reperfusion-induced ALI at the dose used (2 mg/kg intraperitoneally). CONCLUSIONS These results have demonstrated, for the first time, a protective effect of Ro5-4864 on experimental ALI induced by ANTU, LPS, and CLP. Ro5-4864 might be a useful therapeutic agent for lung diseases, including ALI, in intensive care patients.
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Affiliation(s)
- Gulcan Kaynar
- Department of Pharmacology, Health Science Institute, Bulent Ecevit University, Kozlu, Zonguldak, Turkey
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82
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The 18 kDa translocator protein influences angiogenesis, as well as aggressiveness, adhesion, migration, and proliferation of glioblastoma cells. Pharmacogenet Genomics 2012; 22:538-50. [PMID: 22547081 DOI: 10.1097/fpc.0b013e3283539cdc] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
BACKGROUND It is known that the mitochondrial 18 kDa translocator protein (TSPO) is present in almost all peripheral tissues and also in glial cells in the brain. TSPO levels are typically enhanced in correlation with tumorigenesis of cancer cells including glioblastoma. Relevant for angiogenesis, TSPO is also present in almost all cells of the cardiovascular system. METHODS We studied the effect of TSPO knockdown by siRNA on various aspects of tumor growth of U118MG glioblastoma cells in two in-vivo models: a nude mouse model with intracerebral implants of U118MG glioblastoma cells and implantation of U118MG glioblastoma cells on the chorionallantoic membrane (CAM) of chicken embryos. In vitro, we further assayed the influence of TSPO on the invasive potential of U118MG cells. RESULTS TSPO knockdown increased tumor growth in both in-vivo models compared with the scrambled siRNA control. Angiogenesis was also increased by TSPO knockdown as determined by a CAM assay. TSPO knockdown led to a decrease in adhesion to the proteins of the extracellular matrix, including fibronectin, collagen I, collagen IV, laminin I, and fibrinogen. TSPO knockdown also led to an enhancement in the migratory capability of U118MG cells, as determined in a modified Boyden chamber. Application of the TSPO ligand 1-(2-chlorophenyl)-N-methyl-N-(1-methylpropyl)-3-isoquinolinecarboxamide (PK 11195) at a concentration of 25 µmol/l in the in-vitro models yielded results similar to those obtained on TSPO knockdown. We found no effects of PK 11195 on TSPO protein expression. Interestingly, at low nmol/l concentrations (around 1 nmol/l), PK 11195 enhanced adhesion to collagen I, suggesting a bimodal concentration effect of PK 11195. CONCLUSION Intact TSPO appears to be able to counteract the invasive and angiogenic characteristics related to the aggressiveness of U118MG glioblastoma cells in vivo and in vitro.
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83
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Wang HJ, Fan J, Papadopoulos V. Translocator protein (Tspo) gene promoter-driven green fluorescent protein synthesis in transgenic mice: an in vivo model to study Tspo transcription. Cell Tissue Res 2012; 350:261-75. [PMID: 22868914 DOI: 10.1007/s00441-012-1478-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Accepted: 06/26/2012] [Indexed: 12/11/2022]
Abstract
Translocator protein (TSPO), previously known as the peripheral-type benzodiazepine receptor, is a ubiquitous drug- and cholesterol-binding protein primarily found in the outer mitochondrial membrane as part of a mitochondrial cholesterol transport complex. TSPO is present at higher levels in steroid-synthesizing and rapidly proliferating tissues and its biological role has been mainly linked to mitochondrial function, steroidogenesis and cell proliferation/apoptosis. Aberrant TSPO levels have been linked to multiple diseases, including cancer, endocrine disorders, brain injury, neurodegeneration, ischemia-reperfusion injury and inflammatory diseases. Investigation of the functions of this protein in vitro and in vivo have been mainly carried out using high-affinity drug ligands, such as isoquinoline carboxamides and benzodiazepines and more recently, gene silencing methods. To establish a model to study the regulation of Tspo transcription in vivo, we generated a transgenic mouse model expressing green fluorescent protein (GFP) from Aequorea coerulescens under control of the Tspo promoter region (Tspo-AcGFP). The expression profiles of Tspo-AcGFP, endogenous TSPO and Tspo mRNA were found to be well-correlated. Tspo-AcGFP synthesis in the transgenic mice was seen in almost every tissue examined and as with TSPO in wild-type mice, Tspo-AcGFP was highly expressed in steroidogenic cells of the endocrine and reproductive systems, epithelial cells of the digestive system, skeletal muscle and other organs. In summary, this transgenic Tspo-AcGFP mouse model recapitulates endogenous Tspo expression patterns and could be a useful, tractable tool for monitoring the transcriptional regulation and function of Tspo in live animal experiments.
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Affiliation(s)
- Hui-Jie Wang
- The Research Institute of the McGill University Health Center, McGill University, Montréal, Québec, H3A 1A4, Canada
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84
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Purinoceptor signaling in malaria-infected erythrocytes. Microbes Infect 2012; 14:779-86. [PMID: 22580091 DOI: 10.1016/j.micinf.2012.04.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2012] [Revised: 04/13/2012] [Accepted: 04/13/2012] [Indexed: 01/25/2023]
Abstract
Human erythrocytes are endowed with ATP release pathways and metabotropic and ionotropic purinoceptors. This review summarizes the pivotal function of purinergic signaling in erythrocyte control of vascular tone, in hemolytic septicemia, and in malaria. In malaria, the intraerythrocytic parasite exploits the purinergic signaling of its host to adapt the erythrocyte to its requirements.
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85
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Camici PG, Rimoldi OE, Gaemperli O, Libby P. Non-invasive anatomic and functional imaging of vascular inflammation and unstable plaque. Eur Heart J 2012; 33:1309-17. [PMID: 22507974 DOI: 10.1093/eurheartj/ehs067] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Over the last several decades, basic cardiovascular research has significantly enhanced our understanding of pathobiological processes leading to formation, progression, and complications of atherosclerotic plaques. By harnessing these advances in cardiovascular biology, imaging has advanced beyond its traditional anatomical domains to a tool that permits probing of particular molecular structures to image cellular behaviour and metabolic pathways involved in atherosclerosis. From the nascent atherosclerotic plaque to the death of inflammatory cells, several potential molecular and micro-anatomical targets for imaging with particular selective imaging probes and with a variety of imaging modalities have emerged from preclinical and animal investigations. Yet, substantive barriers stand between experimental use and wide clinical application of these novel imaging strategies. Each of the imaging modalities described herein faces hurdles-for example, sensitivity, resolution, radiation exposure, reproducibility, availability, standardization, or costs. This review summarizes the published literature reporting on functional imaging of vascular inflammation in atherosclerotic plaques emphasizing those techniques that have the greatest and/or most immediate potential for broad application in clinical practice. The prospective evaluation of these techniques and standardization of protocols by multinational networks could serve to determine their added value in clinical practice and guide their development and deployment.
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Affiliation(s)
- Paolo G Camici
- Vita-Salute University and Scientific Institute San Raffaele, Via Olgettina 60, Milan, Italy.
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86
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Joo HK, Lee YR, Lim SY, Lee EJ, Choi S, Cho EJ, Park MS, Ryoo S, Park JB, Jeon BH. Peripheral benzodiazepine receptor regulates vascular endothelial activations via suppression of the voltage-dependent anion channel-1. FEBS Lett 2012; 586:1349-55. [PMID: 22616995 DOI: 10.1016/j.febslet.2012.03.049] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Revised: 03/18/2012] [Accepted: 03/22/2012] [Indexed: 01/22/2023]
Abstract
Peripheral benzodiazepine receptor (PBR) is a multifunctional protein mainly found on the outer mitochondrial membrane. PBR expression is increased by tumor necrosis factor-α (TNF-α) in endothelial cells. Adenoviral overexpression of PBR inhibits monocyte adhesion, VCAM-1, and ICAM-1 expression in TNF-α-activated endothelial cells. Rotenone, cyclosporine A, and bongkrekic acid suppress TNF-α-induced VCAM-1 expression. Overexpression of PBR inhibits voltage-dependent anion channel-1 (VDAC-1) expression and the silencing of PBR increases VDAC-1 expression in endothelial cells. Moreover, TNF-α-induced VCAM-1 expression is suppressed by VDAC-1 gene silencing. PBR overexpression significantly decreases TNF-α-induced mitochondrial reactive oxygen species and MnSOD expression. These results suggest that PBR can inhibit endothelial activation and this action is related to the inhibition of mitochondrial ROS and/or VDAC-1 expression in endothelial cells.
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Affiliation(s)
- Hee Kyoung Joo
- Infectious Signaling Network Research Center and Research Institute for Medical Sciences, Department of Physiology, School of Medicine, Chungnam National University, Daejeon, Republic of Korea
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Abstract
Cardiac hypertrophy (CH) is an adaptive response of the heart to pressure overload. It is a common pathological feature in the natural course of some major cardiovascular diseases, like, hypertension and myocardial infarction. Cardiac hypertrophy is strongly associated with an increased risk of heart failure and sudden cardiac death. The complex and dynamic pathophysiological mechanisms of CH has been the focus of intense scientific investigation, in an effort to design preventive and curative strategies. Oxidative stress has been identified as one of the key contributing factors in the development of cardiac hypertrophy. In this review, evidences supporting the oxidative stress as a cause of cardiac hypertrophy with emphasis on mitochondrial oxidative stress and possible options for pharmacological interventions have been discussed. Reactive oxygen species (ROS) also activate a broad variety of hypertrophy signaling kinases and transcription factors, like, MAP kinase, NF K-B, etc. In addition to profound alteration of cellular function, ROS modulate the extracellular matrix function, evidenced by increased interstitial and perivascular fibrosis. Translocator protein (TSPO) present in the outer mitochondrial membrane is known to be involved in oxidative stress and cardiovascular pathology. Recently, its role in cardiac hypertrophy has been reported by us. All these evidences strongly provide support to beneficial role of drugs which selectively interfere with the generation of free radicals or augment endogenous antioxidants in cardiac hypertrophy.
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Affiliation(s)
- Subir Kumar Maulik
- Department of Pharmacology, All India Institute of Medical Sciences, New Delhi, India.
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88
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Shoshan-Barmatz V, Ben-Hail D. VDAC, a multi-functional mitochondrial protein as a pharmacological target. Mitochondrion 2012; 12:24-34. [DOI: 10.1016/j.mito.2011.04.001] [Citation(s) in RCA: 177] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2010] [Revised: 02/16/2011] [Accepted: 04/14/2011] [Indexed: 12/31/2022]
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McCommis KS, Baines CP. The role of VDAC in cell death: friend or foe? BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1818:1444-50. [PMID: 22062421 DOI: 10.1016/j.bbamem.2011.10.025] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2011] [Revised: 10/18/2011] [Accepted: 10/24/2011] [Indexed: 11/16/2022]
Abstract
As the voltage-dependent anion channel (VDAC) forms the interface between mitochondria and the cytosol, its importance in metabolism is well understood. However, research on VDAC's role in cell death is a rapidly growing field, unfortunately with much confusing and contradictory results. The fact that VDAC plays a role in outer mitochondrial membrane permeabilization is undeniable, however, the mechanisms behind this remain very poorly understood. In this review, we will summarize the studies that show evidence of VDAC playing a role in cell death. To begin, we will discuss the evidence for and against VDAC's involvement in mitochondrial permeability transition (MPT) and attempt to clarify that VDAC is not an essential component of the MPT pore (MPTP). Next, we will evaluate the remaining literature on VDAC in cell death which can be divided into three models: proapoptotic agents escaping through VDAC, VDAC homo- or hetero-oligomerization, or VDAC closure resulting in outer mitochondrial membrane permeabilization through an unknown pathway. We will then discuss the growing list of modulators of VDAC activity that have been associated with induction/protection against cell death. This article is part of a Special Issue entitled: VDAC structure, function, and regulation of mitochondrial metabolism.
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Affiliation(s)
- Kyle S McCommis
- Department of Biomedical Sciences, University of Missouri, USA
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90
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Cappelli A, Bini G, Valenti S, Giuliani G, Paolino M, Anzini M, Vomero S, Giorgi G, Giordani A, Stasi LP, Makovec F, Ghelardini C, Di Cesare Mannelli L, Concas A, Porcu P, Biggio G. Synthesis and Structure–Activity Relationship Studies in Translocator Protein Ligands Based on a Pyrazolo[3,4-b]quinoline Scaffold. J Med Chem 2011; 54:7165-75. [DOI: 10.1021/jm200770f] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Andrea Cappelli
- Dipartimento Farmaco Chimico Tecnologico and European Research Centre for Drug Discovery and Development, Università degli Studi di Siena, Via A. Moro, 53100 Siena, Italy
| | - Giulia Bini
- Dipartimento Farmaco Chimico Tecnologico and European Research Centre for Drug Discovery and Development, Università degli Studi di Siena, Via A. Moro, 53100 Siena, Italy
| | - Salvatore Valenti
- Dipartimento Farmaco Chimico Tecnologico and European Research Centre for Drug Discovery and Development, Università degli Studi di Siena, Via A. Moro, 53100 Siena, Italy
| | - Germano Giuliani
- Dipartimento Farmaco Chimico Tecnologico and European Research Centre for Drug Discovery and Development, Università degli Studi di Siena, Via A. Moro, 53100 Siena, Italy
| | - Marco Paolino
- Dipartimento Farmaco Chimico Tecnologico and European Research Centre for Drug Discovery and Development, Università degli Studi di Siena, Via A. Moro, 53100 Siena, Italy
| | - Maurizio Anzini
- Dipartimento Farmaco Chimico Tecnologico and European Research Centre for Drug Discovery and Development, Università degli Studi di Siena, Via A. Moro, 53100 Siena, Italy
| | - Salvatore Vomero
- Dipartimento Farmaco Chimico Tecnologico and European Research Centre for Drug Discovery and Development, Università degli Studi di Siena, Via A. Moro, 53100 Siena, Italy
| | - Gianluca Giorgi
- Dipartimento di Chimica, Università degli Studi di Siena, Via A. Moro, 53100 Siena, Italy
| | | | | | | | - Carla Ghelardini
- Dipartimento di Farmacologia Preclinica e Clinica “M. Aiazzi Mancini”, Università degli Studi di Firenze,Viale G. Pieraccini 6, 50139 Firenze, Italy
| | - Lorenzo Di Cesare Mannelli
- Dipartimento di Farmacologia Preclinica e Clinica “M. Aiazzi Mancini”, Università degli Studi di Firenze,Viale G. Pieraccini 6, 50139 Firenze, Italy
| | - Alessandra Concas
- Dipartimento di Biologia Sperimentale “B. Loddo”, Università degli Studi di Cagliari, Cittadella Universitaria, SS 554 (km 4.500), 09042 Monserrato (Cagliari), Italy
| | - Patrizia Porcu
- Dipartimento di Biologia Sperimentale “B. Loddo”, Università degli Studi di Cagliari, Cittadella Universitaria, SS 554 (km 4.500), 09042 Monserrato (Cagliari), Italy
| | - Giovanni Biggio
- Dipartimento di Biologia Sperimentale “B. Loddo”, Università degli Studi di Cagliari, Cittadella Universitaria, SS 554 (km 4.500), 09042 Monserrato (Cagliari), Italy
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91
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Gaemperli O, Shalhoub J, Owen DRJ, Lamare F, Johansson S, Fouladi N, Davies AH, Rimoldi OE, Camici PG. Imaging intraplaque inflammation in carotid atherosclerosis with 11C-PK11195 positron emission tomography/computed tomography. Eur Heart J 2011; 33:1902-10. [PMID: 21933781 DOI: 10.1093/eurheartj/ehr367] [Citation(s) in RCA: 182] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
AIMS We sought to determine whether intraplaque inflammation could be measured with positron emission tomography/computed tomography angiography (PET/CTA) using (11)C-PK11195, a selective ligand of the translocator protein (18 kDa) (TSPO) which is highly expressed by activated macrophages. METHODS AND RESULTS Patients (n = 32; mean age 70 ± 9 years) with carotid stenoses (n = 36; 9 symptomatic and 27 asymptomatic) underwent (11)C-PK11195 PET/CTA imaging. (11)C-PK11195 uptake into carotid plaques was measured using target-to-background ratios (TBR). On CTA images, plaque composition was assessed by measuring CT attenuation of the carotid plaque. Eight patients underwent carotid endarterectomy and ultrathin contiguous sections were processed for TSPO and CD68 (using immunohistochemical staining, (3)H-PK11195 autoradiography, and confocal fluorescence microscopy). Carotid plaques associated with ipsilateral symptoms (stroke or transient ischaemic attack) had higher TBR (1.06 ± 0.20 vs. 0.86 ± 0.11, P = 0.001) and lower CT attenuation [(median, inter-quartile range) 37, 24-40 vs. 71, 56-125 HU, P = 0.01] than those without. On immunohistochemistry and confocal fluorescence microscopy, CD68 and PBR co-localized with (3)H-PK11195 uptake at autoradiography. There was a significant correlation between (11)C-PK11195 TBR and autoradiographic percentage-specific binding (r = 0.77, P = 0.025). Both TBR and CT plaque attenuation had high negative predictive values (91 and 92%, respectively) for detecting symptomatic patients. However, the best positive predictive value (100%) was achieved when TBR and CT attenuation were combined. CONCLUSION Imaging intraplaque inflammation in vivo with (11)C-PK11195 PET/CTA is feasible and can distinguish between recently symptomatic and asymptomatic plaques. Patients with a recent ischaemic event had ipsilateral plaques with lower CT attenuation and increased (11)C-PK11195 uptake.
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Affiliation(s)
- Oliver Gaemperli
- Medical Research Council Clinical Sciences Centre and National Heart and Lung Institute, Hammersmith Hospital, Imperial College, London, UK
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92
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Zulian A, Sileikytė J, Petronilli V, Bova S, Dabbeni-Sala F, Cargnelli G, Rennison D, Brimble MA, Hopkins B, Bernardi P, Ricchelli F. The translocator protein (peripheral benzodiazepine receptor) mediates rat-selective activation of the mitochondrial permeability transition by norbormide. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1807:1600-5. [PMID: 21889488 DOI: 10.1016/j.bbabio.2011.08.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 07/29/2011] [Accepted: 08/10/2011] [Indexed: 11/30/2022]
Abstract
We have investigated the mechanism of rat-selective induction of the mitochondrial permeability transition (PT) by norbormide (NRB). We show that the inducing effect of NRB on the PT (i) is inhibited by the selective ligands of the 18kDa outer membrane (OMM) translocator protein (TSPO, formerly peripheral benzodiazepine receptor) protoporphyrin IX, N,N-dihexyl-2-(4-fluorophenyl)indole-3-acetamide and 7-chloro-5-(4-chlorophenyl)-1,3-dihydro-1-methyl-2H-1,4-benzodiazepin-2-one; and (ii) is lost in digitonin mitoplasts, which lack an intact OMM. In mitoplasts the PT can still be induced by the NRB cationic derivative OL14, which contrary to NRB is also effective in intact mitochondria from mouse and guinea pig. We conclude that selective NRB transport into rat mitochondria occurs via TSPO in the OMM, which allows its translocation to PT-regulating sites in the inner membrane. Thus, species-specificity of NRB toward the rat PT depends on subtle differences in the structure of TSPO or of TSPO-associated proteins affecting its substrate specificity.
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Affiliation(s)
- Alessandra Zulian
- C.N.R. Institute of Neurosciences at the Department of Biomedical Sciences, University of Padova, Italy
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93
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Erythrocyte peripheral type benzodiazepine receptor/voltage-dependent anion channels are upregulated by Plasmodium falciparum. Blood 2011; 118:2305-12. [PMID: 21795748 DOI: 10.1182/blood-2011-01-329300] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Plasmodium falciparum relies on anion channels activated in the erythrocyte membrane to ensure the transport of nutrients and waste products necessary for its replication and survival after invasion. The molecular identity of these anion channels, termed "new permeability pathways" is unknown, but their currents correspond to up-regulation of endogenous channels displaying complex gating and kinetics similar to those of ligand-gated channels. This report demonstrates that a peripheral-type benzodiazepine receptor, including the voltage dependent anion channel, is present in the human erythrocyte membrane. This receptor mediates the maxi-anion currents previously described in the erythrocyte membrane. Ligands that block this peripheral-type benzodiazepine receptor reduce membrane transport and conductance in P falciparum-infected erythrocytes. These ligands also inhibit in vitro intraerythrocytic growth of P falciparum. These data support the hypothesis that dormant peripheral-type benzodiazepine receptors become the "new permeability pathways" in infected erythrocytes after up-regulation by P falciparum. These channels are obvious targets for selective inhibition in anti-malarial therapies, as well as potential routes for drug delivery in pharmacologic applications.
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94
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Surinkaew S, Chattipakorn S, Chattipakorn N. Roles of mitochondrial benzodiazepine receptor in the heart. Can J Cardiol 2011; 27:262.e3 -13. [PMID: 21459278 DOI: 10.1016/j.cjca.2010.12.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Accepted: 06/02/2010] [Indexed: 12/01/2022] Open
Abstract
Mitochondrial benzodiazepine receptor (mBzR) is a type of peripheral benzodiazepine receptor that is located in the outer membrane of mitochondria. It is an 18-kDa protein that can form a multimeric complex with voltage-dependent anion channel (32 kDa) and adenine nucleotide translocator (30 kDa). mBzR is found in various species and abundantly distributed in peripheral tissues, including the cardiovascular system. The mitochondria are well known as the site of energy production, and the heart is the organ that highly requires this energy supply. In the past decades, it has been shown that mBzR plays a critical role in regulating mitochondrial and heart functions. A growing body of evidence demonstrates that mBzR is associated with regulation of mitochondrial respiration, mitochondrial membrane potential, apoptosis, and reactive oxygen species production. Moreover, mBzR has been suggested to play a role in alteration of physiological effects in the heart such as contractility and heart rate. mBzR is involved in the pathologic condition such as ischemia/reperfusion injury, responses to stress, and changes in electrophysiological properties and arrhythmogenesis. In this review, evidence of the roles of mBzR in the heart under both physiological and pathologic conditions is presented. Clinical studies regarding the use of pharmacologic intervention involving mBzR in the heart are also discussed as a possible target for the treatment of electrical and mechanical dysfunction in the heart.
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Affiliation(s)
- Sirirat Surinkaew
- Department of Physiology, Chiang Mai University, Chiang Mai, Thailand
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95
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Colussi GL, Di Fabio A, Catena C, Chiuch A, Sechi LA. Involvement of endothelium-dependent and -independent mechanisms in midazolam-induced vasodilation. Hypertens Res 2011; 34:929-34. [DOI: 10.1038/hr.2011.62] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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96
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Thomas SL, Bouyer G, Cueff A, Egée S, Glogowska E, Ollivaux C. Ion channels in human red blood cell membrane: Actors or relics? Blood Cells Mol Dis 2011; 46:261-5. [DOI: 10.1016/j.bcmd.2011.02.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Accepted: 02/15/2011] [Indexed: 10/18/2022]
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97
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Onyimba JA, Coronado MJ, Garton AE, Kim JB, Bucek A, Bedja D, Gabrielson KL, Guilarte TR, Fairweather D. The innate immune response to coxsackievirus B3 predicts progression to cardiovascular disease and heart failure in male mice. Biol Sex Differ 2011; 2:2. [PMID: 21338512 PMCID: PMC3049118 DOI: 10.1186/2042-6410-2-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2010] [Accepted: 02/21/2011] [Indexed: 01/05/2023] Open
Abstract
Background Men are at an increased risk of dying from heart failure caused by inflammatory heart diseases such as atherosclerosis, myocarditis and dilated cardiomyopathy (DCM). We previously showed that macrophages in the spleen are phenotypically distinct in male compared to female mice at 12 h after infection. This innate immune profile mirrors and predicts the cardiac immune response during acute myocarditis. Methods In order to study sex differences in the innate immune response, five male and female BALB/c mice were infected intraperitoneally with coxsackievirus B3 (CVB3) or phosphate buffered saline and their spleens were harvested 12 h later for microarray analysis. Gene expression was determined using an Affymetrix Mouse Gene 1.0 ST Array. Significant gene changes were verified by quantitative real-time polymerase chain reaction or ELISA. Results During the innate immune response to CVB3 infection, infected males had higher splenic expression of genes which are important in regulating the influx of cholesterol into macrophages, such as phospholipase A2 (PLA2) and the macrophage scavenger receptor compared to the infected females. We also observed a higher expression in infected males compared to infected females of squalene synthase, an enzyme used to generate cholesterol within cells, and Cyp2e1, an enzyme important in metabolizing cholesterol and steroids. Infected males also had decreased levels of the translocator protein 18 kDa (TSPO), which binds PLA2 and is the rate-limiting step for steroidogenesis, as well as decreased expression of the androgen receptor (AR), which indicates receptor activation. Gene differences were not due to increased viral replication, which was unaltered between sexes. Conclusions We found that, compared to females, male mice had a greater splenic expression of genes which are important for cholesterol metabolism and activation of the AR at 12 h after infection. Activation of the AR has been linked to increased cardiac hypertrophy, atherosclerosis, myocarditis/DCM and heart failure in male mice and humans.
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Affiliation(s)
- Jennifer A Onyimba
- Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Michael J Coronado
- Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Amanda E Garton
- Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Joseph B Kim
- Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Adriana Bucek
- Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Djahida Bedja
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Kathleen L Gabrielson
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Tomas R Guilarte
- Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA.,Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY 10032, USA
| | - DeLisa Fairweather
- Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA.,Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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98
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Chen Y, Sajjad M, Wang Y, Batt C, Nabi HA, Pandey RK. TSPO 18 kDa (PBR) Targeted Photosensitizers for Cancer Imaging (PET) and PDT. ACS Med Chem Lett 2011; 2:136-41. [PMID: 24900292 DOI: 10.1021/ml100211g] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2010] [Accepted: 11/16/2010] [Indexed: 11/28/2022] Open
Abstract
Translocator protein (TSPO) 18 kDa overexpression has been observed in a large variety of human cancers, especially breast cancers. PK 11195, an isoquinoline analogue, is one of the ligands of highest TSPO binding affinity. Due to the long biological half life of our photosensitizers, there is a need to label them with a long lived radioisotope, for example I-124. Our objectives are to find translocator protein targeted photosensitizers for both tumor imaging (PET) and photodynamic therapy (PDT). I-PK 11195 is conjugated with the tumor avid photosensitizer HPPH. We find that those two tumor avid components complement each other and make the conjugate molecule even more tumor avid; compared to the photosensitizer itself, the conjugate is found to show improved PDT efficacy. It is concluded that I-PK 11195 can be a good vehicle to deliver radionuclide and photosensitizer to TSPO overexpressed tumor regions. Such conjugates could be useful for both tumor imaging (PET) and PDT.
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Affiliation(s)
- Yihui Chen
- PDT Center, Roswell Park Cancer Institute, Buffalo, New York 14263, United States
- Department of Nuclear Medicine, State University of New York, Buffalo, New York 14214, United States
| | - Munawwar Sajjad
- Department of Nuclear Medicine, State University of New York, Buffalo, New York 14214, United States
| | - Yanfang Wang
- PDT Center, Roswell Park Cancer Institute, Buffalo, New York 14263, United States
| | - Carrie Batt
- PDT Center, Roswell Park Cancer Institute, Buffalo, New York 14263, United States
| | - Hani A. Nabi
- Department of Nuclear Medicine, State University of New York, Buffalo, New York 14214, United States
| | - Ravindra K. Pandey
- PDT Center, Roswell Park Cancer Institute, Buffalo, New York 14263, United States
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Dimitrova-Shumkovska J, Veenman L, Ristoski T, Leschiner S, Gavish M. Decreases in binding capacity of the mitochondrial 18 kda translocator protein accompany oxidative stress and pathological signs in rat liver after DMBA exposure. Toxicol Pathol 2011; 38:957-68. [PMID: 21037200 DOI: 10.1177/0192623310379137] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
7,12-Dimethylbenz[a]anthracene (DMBA) presents a pollutant implicated in various toxicological effects. The aim of this experiment was to study the effects of DMBA administration on oxidative stress, histopathological signs, and 18 kDa translocator protein (TSPO) binding characteristics in rat liver. We also studied the effects of dose stoichiometry, dose frequency, and duration of protocol of DMBA administration. In this study, rats surviving eighteen weeks after DMBA exposure showed mild to moderate histopathological changes in the liver, mainly characterized by glossy appearance of hepatocytes, heterochromatic nuclei, and glycogen overload in the midzonal region of the hepatic lobe. These changes were accompanied by significant rises in oxidant levels, along with declines in nonenzymic antioxidants, indicating that DMBA induced oxidative stress in the liver. This finding correlated well with decreases in TSPO binding capacity in the liver of the rats in our study. Other studies have shown that TSPO can be affected by oxidative stress, as well as contribute to oxidative stress at mitochondrial levels. Further studies are needed to assay whether the decreases in TSPO density in the liver are part of the damaging effects caused by DMBA or a compensatory response to the oxidative stress induced by DMBA.
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Affiliation(s)
- Jasmina Dimitrova-Shumkovska
- Institute of Biology, Department of Biochemistry and Physiology, Faculty of Natural Sciences and Mathematics, Ss. Cyril and Methodius University, Skopje, Republic of Macedonia.
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Rupprecht R, Papadopoulos V, Rammes G, Baghai TC, Fan J, Akula N, Groyer G, Adams D, Schumacher M. Translocator protein (18 kDa) (TSPO) as a therapeutic target for neurological and psychiatric disorders. Nat Rev Drug Discov 2011; 9:971-88. [PMID: 21119734 DOI: 10.1038/nrd3295] [Citation(s) in RCA: 727] [Impact Index Per Article: 55.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The translocator protein (18 kDa) (TSPO) is localized primarily in the outer mitochondrial membrane of steroid-synthesizing cells, including those in the central and peripheral nervous system. One of its main functions is the transport of the substrate cholesterol into mitochondria, a prerequisite for steroid synthesis. TSPO expression may constitute a biomarker of brain inflammation and reactive gliosis that could be monitored by using TSPO ligands as neuroimaging agents. Moreover, initial clinical trials have indicated that TSPO ligands might be valuable in the treatment of neurological and psychiatric disorders. This Review focuses on the biology and pathophysiology of TSPO and the potential of currently available TSPO ligands for the diagnosis and treatment of neurological and psychiatric disorders.
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Affiliation(s)
- Rainer Rupprecht
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians University, Nussbaumstrasse 7, 80336 Munich, Germany.
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