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Translocator protein

Translocator protein (TSPO) is an 18 kDa protein mainly found on the outer mitochondrial membrane.[5] It was first described as peripheral benzodiazepine receptor (PBR), a secondary binding site for diazepam, but subsequent research has found the receptor to be expressed throughout the body and brain.[6] In humans, the translocator protein is encoded by the TSPO gene.[7][8] It belongs to a family of tryptophan-rich sensory proteins. Regarding intramitochondrial cholesterol transport, TSPO has been proposed to interact with StAR (steroidogenic acute regulatory protein) to transport cholesterol into mitochondria, though evidence is mixed.[9]

TSPO
Identifiers
AliasesTSPO, BPBS, BZRP, DBI, IBP, MBR, PBR, PBS, PKBS, PTBR, mDRC, pk18, translocator protein
External IDsOMIM: 109610 MGI: 88222 HomoloGene: 574 GeneCards: TSPO
Orthologs
SpeciesHumanMouse
Entrez
Ensembl
UniProt
RefSeq (mRNA)

NM_000714
NM_001256530
NM_001256531
NM_007311

NM_009775

RefSeq (protein)

NP_033905

Location (UCSC)Chr 22: 43.15 – 43.16 MbChr 15: 83.45 – 83.46 Mb
PubMed search[3][4]
Wikidata
View/Edit HumanView/Edit Mouse

Function edit

In animals, TSPO (PBR) is a mitochondrial protein usually located in the outer mitochondrial membrane and characterised by its ability to bind a variety of benzodiazepine-like drugs, as well as to dicarboxylic tetrapyrrole intermediates of the haem biosynthetic pathway.

TSPO has many proposed functions depending on the tissue.[10] The most studied of these include roles in the immune response, steroid synthesis and apoptosis.

Cholesterol transport and bile acid biosynthesis edit

Mitochondrial cholesterol transport is a molecular function closely tied to TSPO in the scientific literature. TSPO binds with high affinity to the lipid cholesterol, and pharmacological ligands of TSPO facilitate cholesterol transport across the mitochondrial intermembrane space to stimulate steroid synthesis and bile acid synthesis in relevant tissues.[11] However, TSPO deletion in genetically engineered mouse models has yielded mixed results regarding the physiological necessity of TSPO's role in steroidogenesis. Deletion of TSPO in steroidogenic Leydig cells did not impair synthesis of the steroid testosterone.[12] Thus, though biochemical and pharmacological experimentation suggest an important role for TSPO in cellular cholesterol transport and steroid biosynthesis,[13] TSPO's necessity in this process remains controversial.

Regulation in the heart edit

TSPO (Translocator protein) acts to regulate heart rate and contractile force by its interaction with voltage-dependent calcium channels in cardiac myocytes.[14] The interaction between TSPO and calcium channels can alter cardiac action potential durations, thus contractility of the heart. In healthy individuals, TSPO has a cardio-protective role. When TSPO is up-regulated in the presence of infections, it can limit the inflammatory response, which can be cardio-damaging.[15]

Immunomodulation edit

PBRs (TSPOs) have many actions on immune cells including modulation of oxidative bursts by neutrophils and macrophages, inhibition of the proliferation of lymphoid cells and secretion of cytokines by macrophages.[16][17] Expression of TSPO is also linked to inflammatory responses that occur after ischemia-reperfusion injury, following hemorrhagic brain injury,[18] and in some neurodegenerative diseases.[citation needed]

Increased expression of TSPO is linked to the inflammatory responses in the heart that may cause myocarditis, which can lead to myocardial necrosis. TSPO is present in mast cells and macrophages, indicating its role in the immune system.[14] Oxidative stress is a strong contributing factor to cardiovascular disease, and often occurs because of inflammation caused by ischemia reperfusion injury.[19] Coxsackievirus B3 (CVB3) causes immune cells CD11b+ (present on macrophages) to stimulate inflammatory infiltration. Functionally, CD11b+ regulates leukocyte adhesion and migration to regulate the inflammatory response.[15] Following infection, CD11b+ is up-regulated, activating these immune responses, which then activate an increased expression of TSPO. These immune cells can cause myocarditis which can progress to dilated cardiomyopathy and heart failure.[15]

Apoptosis edit

Ligands of TSPO have been shown to induce apoptosis in human colorectal cancer cells.[citation needed] In lymphatic tissues, TSPO modulates apoptosis of thymocytes via reduction of mitochondrial transmembrane potential.[20]

Stress adaptation edit

TSPO in the basal land plant Physcomitrella patens, a moss, is essential for adaptation to salt stress.[21]

Tissue distribution edit

TSPO is found in many regions of the body including the human iris/ciliary-body.[22] Other tissues include the heart, liver, adrenal and testis, as well as hemopoietic and lymphatic cells.[23] "Peripheral" benzodiazepine receptors are also found in the brain, although only at around a quarter the expression levels of the "central" benzodiazepine receptors located at the plasma membrane.[24]

Therapeutic applications edit

TSPO has been shown to be involved in a number of processes such as inflammation,[16][25] and TSPO ligands may be useful anti-cancer drugs.[26][27]

Pharmacological activation of TSPO has been observed to be a potent stimulator of steroid biosynthesis[28][29] including neuroactive steroids such as allopregnanolone in the brain, which exert anxiolytic properties.[30] Thus, TSPO ligands such as emapunil, alpidem, and etifoxine have been proposed to be useful as potential anxiolytics which may have less addiction-based side effects than traditional benzodiazepine-type drugs.,[31][32][33][34] though toxicity side-effects remain a significant barrier in drug development.[35]

A 2013 study led by researchers from USC Davis School of Gerontology showed that TSPO ligands can prevent and at least partially correct abnormalities present in a mouse model of Alzheimer's disease.[36]

TSPO as a biomarker is a newly discovered non-invasive procedure, and has also been linked as a biomarker for other cardiovascular related diseases including: myocardial infarction (due to ischemic reperfusion), cardiac hypertrophy, atherosclerosis, arrhythmias, and large vessel vasculitis.[19] TSPO can be used as a biomarker to detect the presence and severity of inflammation in the heart and atherosclerotic plaques.[15] Inhibiting the over-production of TSPO can lead to a reduced incidence of arrhythmias which are most often caused by ischemia reperfusion injury.[19] TSPO ligands are used as a therapy after ischemia reperfusion injury to preserve the action potentials in cardiac tissue and restore normal electrical activity of the heart.[14] Higher levels of TSPO are present in those with heart disease, a change that is more common in men than women because testosterone worsens the inflammation causing permanent damage to the heart.[15]

The first high-resolution 3D solution structure of mammalian (mouse) translocator protein (TSPO) in a complex with its diagnostic PK11195 ligand was determined by means of NMR spectroscopy techniques by scientists from the Max-Planck Institute for Biophysical Chemistry in Goettingen in Germany in March 2014 (Jaremko et al., 2014) and has a PDB id: 2MGY. Obtained high-resolution clearly confirms a helical character of a protein and its complex with a diagnostic ligand in solution. The 3D structure of the mTSPO-PK11195 complex comprises five transmembrane α-helices (TM1 to TM5) that tightly pack together in the clockwise order TM1-TM2-TM5-TM4-TM3 (cytosol view). The mammalian TSPO in a complex with diagnostic ligand is nomomeric. The loop located in between TM1 and TM2 helices closes the entrance to the space between helices in which are bound with PK11195 molecule. Site-directed mutagenesis studies of mTSPO revealed that region important for PK11195 binding comprise amino acids from 41 to 51, because the deletion of this region resulted in the decrease in PK11195 binding (Fan et al., 2012).

The mammalian TSPO in a complex with the diagnostic ligand PK11195 is monomeric.[37][38]

Imaging edit

Ligands of the TSPO are very useful for imaging of inflammation. For example, the radioligand [3H]PK-11195 has been used in receptor autoradiography to study neuroinflammation following brain injury. The affinity of [11C]PBR28 depends on a single polymorphism (rs6971) in the TSPO gene.[39]

Measuring microglial activation in vivo is possible using PET imaging and radioligands binding to 18 kDa translocator protein (TSPO).[40] Activation can be measured using the PET tracer (R)-[11C]PK11195 and others like PBR28 are under research.[41]

Ligands edit

TSPO ligands[5] (endogenous or synthetic) modulate the action of this receptor, activating the transport of cholesterol from the outer to the inner mitochondrial membrane.

Agonists edit

  • YL-IPA08
  • Ro5-4864 - original ligand with which TSPO receptor was characterised, now less used due to inter-species differences in binding affinity. Sedative yet also convulsant and anxiogenic in mice.[42]
Peptides
  • Anthralin - 16kDa polypeptide, binds to both TSPO receptor and dihydropyridine-sensitive calcium channels with high affinity.[43]
  • Diazepam binding inhibitor (DBI) - 11kDa neuropeptide, potent agonist for TSPO receptor and stimulates steroidogenesis in vivo,[44][45][46] also negative allosteric modulator of benzodiazepine-sensitive GABAA receptors.[47]
  • DBI 17-50 fragment - active processing product of DBI
Non-peptides

Antagonists edit

  • PK-11195 - potent and selective antagonist for both rat and human forms of TSPO.

See also edit

References edit

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External links edit

translocator, protein, tspo, protein, mainly, found, outer, mitochondrial, membrane, first, described, peripheral, benzodiazepine, receptor, secondary, binding, site, diazepam, subsequent, research, found, receptor, expressed, throughout, body, brain, humans, . Translocator protein TSPO is an 18 kDa protein mainly found on the outer mitochondrial membrane 5 It was first described as peripheral benzodiazepine receptor PBR a secondary binding site for diazepam but subsequent research has found the receptor to be expressed throughout the body and brain 6 In humans the translocator protein is encoded by the TSPO gene 7 8 It belongs to a family of tryptophan rich sensory proteins Regarding intramitochondrial cholesterol transport TSPO has been proposed to interact with StAR steroidogenic acute regulatory protein to transport cholesterol into mitochondria though evidence is mixed 9 TSPOIdentifiersAliasesTSPO BPBS BZRP DBI IBP MBR PBR PBS PKBS PTBR mDRC pk18 translocator proteinExternal IDsOMIM 109610 MGI 88222 HomoloGene 574 GeneCards TSPOGene location Human Chr Chromosome 22 human 1 Band22q13 2Start43 151 547 bp 1 End43 163 242 bp 1 Gene location Mouse Chr Chromosome 15 mouse 2 Band15 E1 15 39 4 cMStart83 447 793 bp 2 End83 458 404 bp 2 RNA expression patternBgeeHumanMouse ortholog Top expressed inmonocyteskin of abdomenminor salivary glandnippleleft coronary arterybody of stomachthoracic aortaascending aortabone marrowhuman penisTop expressed inwhite adipose tissuebrown adipose tissueadrenal glandpyloric antrumsubcutaneous adipose tissuecarotid bodyintercostal musclelipbone marrowmucous cell of stomachMore reference expression dataBioGPSn aGene ontologyMolecular functiontransmembrane transporter binding androgen binding benzodiazepine receptor activity cholesterol binding protein binding cholesterol transfer activityCellular componentmitochondrial outer membrane mitochondrion integral component of membrane membrane mitochondrial membranes extracellular exosome endoplasmic reticulumBiological processpositive regulation of necrotic cell death response to vitamin B1 response to testosterone negative regulation of glial cell proliferation response to progesterone negative regulation of ATP metabolic process human ageing regulation of steroid biosynthetic process contact inhibition cellular hypotonic response negative regulation of mitochondrion organization negative regulation of autophagy of mitochondrion ion transport adrenal gland development cellular response to zinc ion negative regulation of protein ubiquitination maintenance of protein location in mitochondrion positive regulation of reactive oxygen species metabolic process negative regulation of nitric oxide biosynthetic process behavioral response to pain response to manganese ion establishment of protein localization to mitochondrion positive regulation of mitochondrial depolarization peripheral nervous system axon regeneration response to pain response to axon injury positive regulation of apoptotic process negative regulation of tumor necrosis factor production chloride transport cellular response to lipopolysaccharide positive regulation of glial cell proliferation glial cell migration steroid biosynthetic process positive regulation of calcium ion transport signal transduction steroid metabolic process lipid transport protein targeting to mitochondrion anion transport regulation of cholesterol transport heme biosynthetic process cell population proliferation apoptotic process C21 steroid hormone biosynthetic process cholesterol transport transport regulation of cell population proliferationSources Amigo QuickGOOrthologsSpeciesHumanMouseEntrez70612257EnsemblENSG00000100300ENSMUSG00000041736UniProtP30536P50637RefSeq mRNA NM 000714NM 001256530NM 001256531NM 007311NM 009775RefSeq protein NP 000705NP 001243459NP 001243460NP 000705 2NP 001243459 1NP 001243460 1NP 033905Location UCSC Chr 22 43 15 43 16 MbChr 15 83 45 83 46 MbPubMed search 3 4 WikidataView Edit HumanView Edit Mouse Contents 1 Function 1 1 Cholesterol transport and bile acid biosynthesis 1 2 Regulation in the heart 1 3 Immunomodulation 1 4 Apoptosis 1 5 Stress adaptation 2 Tissue distribution 3 Therapeutic applications 4 Imaging 5 Ligands 5 1 Agonists 5 2 Antagonists 6 See also 7 References 8 External linksFunction editIn animals TSPO PBR is a mitochondrial protein usually located in the outer mitochondrial membrane and characterised by its ability to bind a variety of benzodiazepine like drugs as well as to dicarboxylic tetrapyrrole intermediates of the haem biosynthetic pathway TSPO has many proposed functions depending on the tissue 10 The most studied of these include roles in the immune response steroid synthesis and apoptosis Cholesterol transport and bile acid biosynthesis edit Mitochondrial cholesterol transport is a molecular function closely tied to TSPO in the scientific literature TSPO binds with high affinity to the lipid cholesterol and pharmacological ligands of TSPO facilitate cholesterol transport across the mitochondrial intermembrane space to stimulate steroid synthesis and bile acid synthesis in relevant tissues 11 However TSPO deletion in genetically engineered mouse models has yielded mixed results regarding the physiological necessity of TSPO s role in steroidogenesis Deletion of TSPO in steroidogenic Leydig cells did not impair synthesis of the steroid testosterone 12 Thus though biochemical and pharmacological experimentation suggest an important role for TSPO in cellular cholesterol transport and steroid biosynthesis 13 TSPO s necessity in this process remains controversial Regulation in the heart edit TSPO Translocator protein acts to regulate heart rate and contractile force by its interaction with voltage dependent calcium channels in cardiac myocytes 14 The interaction between TSPO and calcium channels can alter cardiac action potential durations thus contractility of the heart In healthy individuals TSPO has a cardio protective role When TSPO is up regulated in the presence of infections it can limit the inflammatory response which can be cardio damaging 15 Immunomodulation edit PBRs TSPOs have many actions on immune cells including modulation of oxidative bursts by neutrophils and macrophages inhibition of the proliferation of lymphoid cells and secretion of cytokines by macrophages 16 17 Expression of TSPO is also linked to inflammatory responses that occur after ischemia reperfusion injury following hemorrhagic brain injury 18 and in some neurodegenerative diseases citation needed Increased expression of TSPO is linked to the inflammatory responses in the heart that may cause myocarditis which can lead to myocardial necrosis TSPO is present in mast cells and macrophages indicating its role in the immune system 14 Oxidative stress is a strong contributing factor to cardiovascular disease and often occurs because of inflammation caused by ischemia reperfusion injury 19 Coxsackievirus B3 CVB3 causes immune cells CD11b present on macrophages to stimulate inflammatory infiltration Functionally CD11b regulates leukocyte adhesion and migration to regulate the inflammatory response 15 Following infection CD11b is up regulated activating these immune responses which then activate an increased expression of TSPO These immune cells can cause myocarditis which can progress to dilated cardiomyopathy and heart failure 15 Apoptosis edit Ligands of TSPO have been shown to induce apoptosis in human colorectal cancer cells citation needed In lymphatic tissues TSPO modulates apoptosis of thymocytes via reduction of mitochondrial transmembrane potential 20 Stress adaptation edit TSPO in the basal land plant Physcomitrella patens a moss is essential for adaptation to salt stress 21 Tissue distribution editTSPO is found in many regions of the body including the human iris ciliary body 22 Other tissues include the heart liver adrenal and testis as well as hemopoietic and lymphatic cells 23 Peripheral benzodiazepine receptors are also found in the brain although only at around a quarter the expression levels of the central benzodiazepine receptors located at the plasma membrane 24 Therapeutic applications editTSPO has been shown to be involved in a number of processes such as inflammation 16 25 and TSPO ligands may be useful anti cancer drugs 26 27 Pharmacological activation of TSPO has been observed to be a potent stimulator of steroid biosynthesis 28 29 including neuroactive steroids such as allopregnanolone in the brain which exert anxiolytic properties 30 Thus TSPO ligands such as emapunil alpidem and etifoxine have been proposed to be useful as potential anxiolytics which may have less addiction based side effects than traditional benzodiazepine type drugs 31 32 33 34 though toxicity side effects remain a significant barrier in drug development 35 A 2013 study led by researchers from USC Davis School of Gerontology showed that TSPO ligands can prevent and at least partially correct abnormalities present in a mouse model of Alzheimer s disease 36 TSPO as a biomarker is a newly discovered non invasive procedure and has also been linked as a biomarker for other cardiovascular related diseases including myocardial infarction due to ischemic reperfusion cardiac hypertrophy atherosclerosis arrhythmias and large vessel vasculitis 19 TSPO can be used as a biomarker to detect the presence and severity of inflammation in the heart and atherosclerotic plaques 15 Inhibiting the over production of TSPO can lead to a reduced incidence of arrhythmias which are most often caused by ischemia reperfusion injury 19 TSPO ligands are used as a therapy after ischemia reperfusion injury to preserve the action potentials in cardiac tissue and restore normal electrical activity of the heart 14 Higher levels of TSPO are present in those with heart disease a change that is more common in men than women because testosterone worsens the inflammation causing permanent damage to the heart 15 The first high resolution 3D solution structure of mammalian mouse translocator protein TSPO in a complex with its diagnostic PK11195 ligand was determined by means of NMR spectroscopy techniques by scientists from the Max Planck Institute for Biophysical Chemistry in Goettingen in Germany in March 2014 Jaremko et al 2014 and has a PDB id 2MGY Obtained high resolution clearly confirms a helical character of a protein and its complex with a diagnostic ligand in solution The 3D structure of the mTSPO PK11195 complex comprises five transmembrane a helices TM1 to TM5 that tightly pack together in the clockwise order TM1 TM2 TM5 TM4 TM3 cytosol view The mammalian TSPO in a complex with diagnostic ligand is nomomeric The loop located in between TM1 and TM2 helices closes the entrance to the space between helices in which are bound with PK11195 molecule Site directed mutagenesis studies of mTSPO revealed that region important for PK11195 binding comprise amino acids from 41 to 51 because the deletion of this region resulted in the decrease in PK11195 binding Fan et al 2012 The mammalian TSPO in a complex with the diagnostic ligand PK11195 is monomeric 37 38 Imaging editLigands of the TSPO are very useful for imaging of inflammation For example the radioligand 3H PK 11195 has been used in receptor autoradiography to study neuroinflammation following brain injury The affinity of 11C PBR28 depends on a single polymorphism rs6971 in the TSPO gene 39 Measuring microglial activation in vivo is possible using PET imaging and radioligands binding to 18 kDa translocator protein TSPO 40 Activation can be measured using the PET tracer R 11C PK11195 and others like PBR28 are under research 41 Ligands editTSPO ligands 5 endogenous or synthetic modulate the action of this receptor activating the transport of cholesterol from the outer to the inner mitochondrial membrane Agonists edit YL IPA08 Ro5 4864 original ligand with which TSPO receptor was characterised now less used due to inter species differences in binding affinity Sedative yet also convulsant and anxiogenic in mice 42 PeptidesAnthralin 16kDa polypeptide binds to both TSPO receptor and dihydropyridine sensitive calcium channels with high affinity 43 Diazepam binding inhibitor DBI 11kDa neuropeptide potent agonist for TSPO receptor and stimulates steroidogenesis in vivo 44 45 46 also negative allosteric modulator of benzodiazepine sensitive GABAA receptors 47 DBI 17 50 fragment active processing product of DBINon peptidesAlpidem DAA 1097 DAA 1106 Deuterated etifoxine DPA 713 DPA 714 Emapunil Etifoxine FGIN 127 FGIN 143 GML 1 Olesoxime TRO19622 48 SSR 180 575Antagonists edit PK 11195 potent and selective antagonist for both rat and human forms of TSPO See also editSteroidogenic enzyme Neurosteroidogenesis inhibitorReferences edit a b c GRCh38 Ensembl release 89 ENSG00000100300 Ensembl May 2017 a b c GRCm38 Ensembl release 89 ENSMUSG00000041736 Ensembl May 2017 Human PubMed Reference National Center for Biotechnology Information U S National Library of Medicine Mouse PubMed Reference National Center for Biotechnology Information U S National Library of Medicine a b Mokrov GV Deeva OA Gudasheva TA 2021 The Ligands of Translocator Protein Design and Biological Properties Current Pharmaceutical Design 27 2 217 237 doi 10 2174 1381612826666200903122025 PMID 32881658 S2CID 221498255 Papadopoulos V Baraldi M Guilarte TR Knudsen TB Lacapere JJ Lindemann P et al August 2006 Translocator protein 18kDa new nomenclature for the peripheral type benzodiazepine receptor based on its structure and molecular function Trends in Pharmacological Sciences 27 8 402 409 doi 10 1016 j tips 2006 06 005 PMID 16822554 Chang YJ McCabe RT Rennert H Budarf ML Sayegh R Emanuel BS et al 1992 The human peripheral type benzodiazepine receptor regional mapping of the gene and characterization of the receptor expressed from cDNA DNA and Cell Biology 11 6 471 480 doi 10 1089 dna 1992 11 471 PMID 1326278 Riond J Mattei MG Kaghad M Dumont X Guillemot JC Le Fur G et al January 1991 Molecular cloning and chromosomal localization of a human peripheral type benzodiazepine receptor European Journal of Biochemistry 195 2 305 311 doi 10 1111 j 1432 1033 1991 tb15707 x PMID 1847678 Bogan RL Davis TL Niswender GD April 2007 Peripheral type benzodiazepine receptor PBR aggregation and absence of steroidogenic acute regulatory protein StAR PBR association in the mitochondrial membrane as determined by bioluminescence resonance energy transfer BRET The Journal of Steroid Biochemistry and Molecular Biology 104 1 2 61 67 doi 10 1016 j jsbmb 2006 10 007 PMID 17197174 S2CID 24634653 Casellas P Galiegue S Basile AS May 2002 Peripheral benzodiazepine receptors and mitochondrial function Neurochemistry International 40 6 475 486 doi 10 1016 S0197 0186 01 00118 8 PMID 11850104 S2CID 18428847 Lacapere JJ Papadopoulos V September 2003 Peripheral type benzodiazepine receptor structure and function of a cholesterol binding protein in steroid and bile acid biosynthesis Steroids 68 7 8 569 585 doi 10 1016 s0039 128x 03 00101 6 PMID 12957662 S2CID 26232564 Morohaku K Pelton SH Daugherty DJ Butler WR Deng W Selvaraj V January 2014 Translocator protein peripheral benzodiazepine receptor is not required for steroid hormone biosynthesis Endocrinology 155 1 89 97 doi 10 1210 en 2013 1556 PMC 3868810 PMID 24174323 Midzak A Papadopoulos V September 2014 Binding domain driven intracellular trafficking of sterols for synthesis of steroid hormones bile acids and oxysterols Traffic 15 9 895 914 doi 10 1111 tra 12177 PMID 24890942 a b c Qi X Xu J Wang F Xiao J 2012 Translocator protein 18 kDa a promising therapeutic target and diagnostic tool for cardiovascular diseases Oxidative Medicine and Cellular Longevity 2012 162934 doi 10 1155 2012 162934 PMC 3516045 PMID 23251719 a b c d e Fairweather D Coronado MJ Garton AE Dziedzic JL Bucek A Cooper LT et al March 2014 Sex differences in translocator protein 18 kDa TSPO in the heart implications for imaging myocardial inflammation Journal of Cardiovascular Translational Research 7 2 192 202 doi 10 1007 s12265 013 9538 0 PMC 3951973 PMID 24402571 a b Wolf A Herb M Schramm M Langmann T June 2020 The TSPO NOX1 axis controls phagocyte triggered pathological angiogenesis in the eye Nature Communications 11 1 2709 Bibcode 2020NatCo 11 2709W doi 10 1038 s41467 020 16400 8 PMC 7264151 PMID 32483169 Pawlikowski M 1993 Immunomodulating effects of peripherally acting benzodiazepines New York In Peripheral Benzodiazepine Receptors Academic press pp 125 135 Ren H Han R Chen X Liu X Wan J Wang L et al September 2020 Potential therapeutic targets for intracerebral hemorrhage associated inflammation An update Journal of Cerebral Blood Flow and Metabolism 40 9 1752 1768 doi 10 1177 0271678X20923551 PMC 7446569 PMID 32423330 a b c Batarseh A Papadopoulos V October 2010 Regulation of translocator protein 18 kDa TSPO expression in health and disease states Molecular and Cellular Endocrinology 327 1 2 1 12 doi 10 1016 j mce 2010 06 013 PMC 2922062 PMID 20600583 Tanimoto Y Onishi Y Sato Y Kizaki H February 1999 Benzodiazepine receptor agonists modulate thymocyte apoptosis through reduction of the mitochondrial transmembrane potential Japanese Journal of Pharmacology 79 2 177 183 doi 10 1254 jjp 79 177 PMID 10202853 Frank W Baar KM Qudeimat E Woriedh M Alawady A Ratnadewi D et al September 2007 A mitochondrial protein homologous to the mammalian peripheral type benzodiazepine receptor is essential for stress adaptation in plants The Plant Journal 51 6 1004 1018 doi 10 1111 j 1365 313X 2007 03198 x PMID 17651369 Valtier D Malgouris C Gilbert JC Guicheney P Uzan A Gueremy C et al June 1987 Binding sites for a peripheral type benzodiazepine antagonist 3H PK 11195 in human iris Neuropharmacology 26 6 549 552 doi 10 1016 0028 3908 87 90146 8 PMID 3037422 S2CID 45035355 Woods MJ Williams DC December 1996 Multiple forms and locations for the peripheral type benzodiazepine receptor Biochemical Pharmacology 52 12 1805 1814 doi 10 1016 S0006 2952 96 00558 8 PMID 8951338 Marangos PJ Patel J Boulenger JP Clark Rosenberg R July 1982 Characterization of peripheral type benzodiazepine binding sites in brain using 3H Ro 5 4864 Molecular Pharmacology 22 1 26 32 PMID 6289073 Chen MK Guilarte TR April 2008 Translocator protein 18 kDa TSPO molecular sensor of brain injury and repair Pharmacology amp Therapeutics 118 1 1 17 doi 10 1016 j pharmthera 2007 12 004 PMC 2453598 PMID 18374421 Santidrian AF Cosialls AM Coll Mulet L Iglesias Serret D de Frias M Gonzalez Girones DM et al December 2007 The potential anticancer agent PK11195 induces apoptosis irrespective of p53 and ATM status in chronic lymphocytic leukemia cells Haematologica 92 12 1631 1638 doi 10 3324 haematol 11194 hdl 2445 127632 PMID 18055986 Kugler W Veenman L Shandalov Y Leschiner S Spanier I Lakomek M Gavish M 2008 Ligands of the mitochondrial 18 kDa translocator protein attenuate apoptosis of human glioblastoma cells exposed to erucylphosphohomocholine Cellular Oncology 30 5 435 450 doi 10 3233 clo 2008 0431 PMC 4618834 PMID 18791274 Veenman L Papadopoulos V Gavish M 2007 Channel like functions of the 18 kDa translocator protein TSPO regulation of apoptosis and steroidogenesis as part of the host defense response Current Pharmaceutical Design 13 23 2385 2405 doi 10 2174 138161207781368710 PMID 17692008 Falchi AM Battetta B Sanna F Piludu M Sogos V Serra M et al August 2007 Intracellular cholesterol changes induced by translocator protein 18 kDa TSPO PBR ligands Neuropharmacology 53 2 318 329 doi 10 1016 j neuropharm 2007 05 016 PMID 17631921 S2CID 39793765 Farb DH Ratner MH October 2014 Targeting the modulation of neural circuitry for the treatment of anxiety disorders Pharmacological Reviews 66 4 1002 1032 doi 10 1124 pr 114 009126 PMID 25237115 S2CID 14537740 Mealy NE Bayes M Lupone B 2006 Psychiatric Disorders Drugs of the Future 31 3 259 Da Settimo F Simorini F Taliani S La Motta C Marini AM Salerno S et al September 2008 Anxiolytic like effects of N N dialkyl 2 phenylindol 3 ylglyoxylamides by modulation of translocator protein promoting neurosteroid biosynthesis Journal of Medicinal Chemistry 51 18 5798 5806 doi 10 1021 jm8003224 PMID 18729350 Taliani S Da Settimo F Da Pozzo E Chelli B Martini C September 2009 Translocator protein ligands as promising therapeutic tools for anxiety disorders Current Medicinal Chemistry 16 26 3359 3380 doi 10 2174 092986709789057653 PMID 19548867 Rupprecht R Rammes G Eser D Baghai TC Schule C Nothdurfter C et al July 2009 Translocator protein 18 kD as target for anxiolytics without benzodiazepine like side effects Science 325 5939 490 493 Bibcode 2009Sci 325 490R doi 10 1126 science 1175055 PMID 19541954 S2CID 26125316 Skolnick P November 2012 Anxioselective anxiolytics on a quest for the Holy Grail Trends in Pharmacological Sciences 33 11 611 620 doi 10 1016 j tips 2012 08 003 PMC 3482271 PMID 22981367 Barron AM Garcia Segura LM Caruso D Jayaraman A Lee JW Melcangi RC Pike CJ May 2013 Ligand for translocator protein reverses pathology in a mouse model of Alzheimer s disease The Journal of Neuroscience 33 20 8891 8897 doi 10 1523 JNEUROSCI 1350 13 2013 PMC 3733563 PMID 23678130 Jaremko L Jaremko M Giller K Becker S Zweckstetter M March 2014 Structure of the mitochondrial translocator protein in complex with a diagnostic ligand Science 343 6177 1363 1366 Bibcode 2014Sci 343 1363J doi 10 1126 science 1248725 PMC 5650047 PMID 24653034 Fan J Lindemann P Feuilloley MG Papadopoulos V May 2012 Structural and functional evolution of the translocator protein 18 kDa Current Molecular Medicine 12 4 369 386 doi 10 2174 156652412800163415 PMID 22364126 Owen DR Yeo AJ Gunn RN Song K Wadsworth G Lewis A et al January 2012 An 18 kDa translocator protein TSPO polymorphism explains differences in binding affinity of the PET radioligand PBR28 Journal of Cerebral Blood Flow and Metabolism 32 1 1 5 doi 10 1038 jcbfm 2011 147 PMC 3323305 PMID 22008728 Airas L Rissanen E Tuisku J Rinne J April 2015 Microglial Activation Correlates with Disease Progression in Multiple Sclerosis Neurology 86 16 Supplement P4 167 Mirzaei N Tang SP Ashworth S Coello C Plisson C Passchier J et al June 2016 In vivo imaging of microglial activation by positron emission tomography with 11 C PBR28 in the 5XFAD model of Alzheimer s disease Glia 64 6 993 1006 doi 10 1002 glia 22978 PMID 26959396 S2CID 25681298 Pellow S File SE July 1984 Behavioural actions of Ro 5 4864 a peripheral type benzodiazepine Life Sciences 35 3 229 240 doi 10 1016 0024 3205 84 90106 1 PMID 6087055 Gavish M Bachman I Shoukrun R Katz Y Veenman L Weisinger G Weizman A December 1999 Enigma of the peripheral benzodiazepine receptor Pharmacological Reviews 51 4 629 650 PMID 10581326 Papadopoulos V Amri H Boujrad N Cascio C Culty M Garnier M et al January 1997 Peripheral benzodiazepine receptor in cholesterol transport and steroidogenesis Steroids 62 1 21 28 doi 10 1016 S0039 128X 96 00154 7 PMID 9029710 S2CID 1977513 Costa E Auta J Guidotti A Korneyev A Romeo E June 1994 The pharmacology of neurosteroidogenesis The Journal of Steroid Biochemistry and Molecular Biology 49 4 6 385 389 doi 10 1016 0960 0760 94 90284 4 PMID 8043504 S2CID 33492066 Garnier M Boujrad N Ogwuegbu SO Hudson JR Papadopoulos V September 1994 The polypeptide diazepam binding inhibitor and a higher affinity mitochondrial peripheral type benzodiazepine receptor sustain constitutive steroidogenesis in the R2C Leydig tumor cell line The Journal of Biological Chemistry 269 35 22105 22112 doi 10 1016 S0021 9258 17 31762 3 PMID 8071335 Bormann J Ferrero P Guidotti A Costa E 1985 Neuropeptide modulation of GABA receptor C1 channels Regulatory Peptides Supplement 4 33 38 doi 10 1016 0167 0115 85 90215 0 PMID 2414820 Bordet T Buisson B Michaud M Drouot C Galea P Delaage P et al August 2007 Identification and characterization of cholest 4 en 3 one oxime TRO19622 a novel drug candidate for amyotrophic lateral sclerosis The Journal of Pharmacology and Experimental Therapeutics 322 2 709 720 doi 10 1124 jpet 107 123000 PMID 17496168 S2CID 17271734 External links editTSPO protein human at the U S National Library of Medicine Medical Subject Headings MeSH Retrieved from https en wikipedia org w index php title Translocator protein amp oldid 1193264038, wikipedia, wiki, book, books, library,

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