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Erazo-Oliveras A, Muñoz-Vega M, Salinas ML, Wang X, Chapkin RS. Dysregulation of cellular membrane homeostasis as a crucial modulator of cancer risk. FEBS J 2024; 291:1299-1352. [PMID: 36282100 PMCID: PMC10126207 DOI: 10.1111/febs.16665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Revised: 09/09/2022] [Accepted: 10/24/2022] [Indexed: 11/07/2022]
Abstract
Cellular membranes serve as an epicentre combining extracellular and cytosolic components with membranous effectors, which together support numerous fundamental cellular signalling pathways that mediate biological responses. To execute their functions, membrane proteins, lipids and carbohydrates arrange, in a highly coordinated manner, into well-defined assemblies displaying diverse biological and biophysical characteristics that modulate several signalling events. The loss of membrane homeostasis can trigger oncogenic signalling. More recently, it has been documented that select membrane active dietaries (MADs) can reshape biological membranes and subsequently decrease cancer risk. In this review, we emphasize the significance of membrane domain structure, organization and their signalling functionalities as well as how loss of membrane homeostasis can steer aberrant signalling. Moreover, we describe in detail the complexities associated with the examination of these membrane domains and their association with cancer. Finally, we summarize the current literature on MADs and their effects on cellular membranes, including various mechanisms of dietary chemoprevention/interception and the functional links between nutritional bioactives, membrane homeostasis and cancer biology.
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Affiliation(s)
- Alfredo Erazo-Oliveras
- Program in Integrative Nutrition and Complex Diseases; Texas A&M University; College Station, Texas, 77843; USA
- Department of Nutrition; Texas A&M University; College Station, Texas, 77843; USA
| | - Mónica Muñoz-Vega
- Program in Integrative Nutrition and Complex Diseases; Texas A&M University; College Station, Texas, 77843; USA
- Department of Nutrition; Texas A&M University; College Station, Texas, 77843; USA
| | - Michael L. Salinas
- Program in Integrative Nutrition and Complex Diseases; Texas A&M University; College Station, Texas, 77843; USA
- Department of Nutrition; Texas A&M University; College Station, Texas, 77843; USA
| | - Xiaoli Wang
- Program in Integrative Nutrition and Complex Diseases; Texas A&M University; College Station, Texas, 77843; USA
- Department of Nutrition; Texas A&M University; College Station, Texas, 77843; USA
| | - Robert S. Chapkin
- Program in Integrative Nutrition and Complex Diseases; Texas A&M University; College Station, Texas, 77843; USA
- Department of Nutrition; Texas A&M University; College Station, Texas, 77843; USA
- Center for Environmental Health Research; Texas A&M University; College Station, Texas, 77843; USA
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2
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Elifranji ZO, Al-Ajlouni JM, Al-Saber MG, Hammad YS, Baniatta BA, Alshoubaki SN, Jabaiti MS, Alkhatib AM, Abu awad AM, Altarazi AE, Abdin AN, Al-Ani A, Alshrouf MA. Effect of Preoperative Antianxiety Medications on Blood Pressure and Blood Loss in Total Knee Arthroplasty: A Case-Control Study. Adv Orthop 2023; 2023:6355849. [PMID: 37456533 PMCID: PMC10349676 DOI: 10.1155/2023/6355849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 05/14/2023] [Accepted: 07/01/2023] [Indexed: 07/18/2023] Open
Abstract
Background The increasing number of canceled operations in patients undergoing total knee arthroplasty (TKA) due to high blood pressure readings has put a considerable burden on surgeons. In this study, we aim to assess the effect of giving antianxiety drugs preoperatively on maintaining blood pressure (BP) and blood loss for patients undergoing TKA surgery. Methods This retrospective case-control study included patients who underwent total knee arthroplasty and divided them into two main groups: those who had taken a 3 mg bromazepam oral tablet at the night preoperatively and the control group. The blood pressure of patients was then measured preoperatively (baseline), in the morning of surgery, in the operating room before anesthesia, and during the surgery. The percentage of measured BP was calculated by dividing the measured BP by the baseline, then multiplying by 100. Results 301 patients were included in our study: 137 received bromazepam and 164 as a control group. The ratio of systolic BP (SBP) in the morning of surgery to the baseline (percentage of morning SBP) decreased significantly in the bromazepam group compared with the controls. The ratio of SBP, in the operating room before anesthesia (percentage of preanesthesia SBP) also decreased significantly in the bromazepam group. However, the percentage of SBP in the middle of surgery did not change significantly. In addition, there was a significant difference change from the baseline in diastolic BP and mean arterial BP between the two groups in the morning of surgery, inside the theatre, and in the middle of the operation. The bromazepam group also showed a significant decrease in blood loss. Conclusion Preoperative oral antianxiety drugs (bromazepam) helps in controlling hemodynamic changes associated with anxiety, including maintaining BP in well-controlled hypertensive and healthy patients undergoing TKA, and it plays a role in decreasing the total blood loss.
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Affiliation(s)
- Zuhdi O. Elifranji
- Department of Special Surgery, Division of Orthopaedics, School of Medicine, The University of Jordan, Amman 11942, Jordan
| | - Jihad M. Al-Ajlouni
- Department of Special Surgery, Division of Orthopaedics, School of Medicine, The University of Jordan, Amman 11942, Jordan
| | - Munther G. Al-Saber
- Department of Special Surgery, Division of Orthopaedics, School of Medicine, The University of Jordan, Amman 11942, Jordan
| | - Yazan S. Hammad
- Department of Special Surgery, Division of Orthopaedics, School of Medicine, The University of Jordan, Amman 11942, Jordan
| | - Basel A. Baniatta
- Department of Special Surgery, Division of Orthopaedics, School of Medicine, The University of Jordan, Amman 11942, Jordan
| | - Sara N. Alshoubaki
- Medical Internship, Jordan University Hospital, The University of Jordan, Amman 11942, Jordan
| | - Mohammad S. Jabaiti
- Department of Special Surgery, Division of Orthopaedics, School of Medicine, The University of Jordan, Amman 11942, Jordan
| | - Ahmad M. Alkhatib
- Department of Special Surgery, Division of Orthopaedics, School of Medicine, The University of Jordan, Amman 11942, Jordan
| | - Abdelrahman M. Abu awad
- Department of Special Surgery, Division of Orthopaedics, School of Medicine, The University of Jordan, Amman 11942, Jordan
| | - Abdelrahman E. Altarazi
- Department of Special Surgery, Division of Orthopaedics, School of Medicine, The University of Jordan, Amman 11942, Jordan
| | - Aseel N. Abdin
- Medical Internship, Jordan University Hospital, The University of Jordan, Amman 11942, Jordan
| | - Abdallah Al-Ani
- Office of Scientific Affairs and Research, King Hussein Cancer Center, Amman 11942, Jordan
| | - Mohammad Ali Alshrouf
- Medical Internship, Jordan University Hospital, The University of Jordan, Amman 11942, Jordan
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Tan Z, Haider A, Zhang S, Chen J, Wei J, Liao K, Li G, Wei H, Dong C, Ran W, Li Y, Li Y, Rong J, Li Y, Liang SH, Xu H, Wang L. Quantitative assessment of translocator protein (TSPO) in the non-human primate brain and clinical translation of [ 18F]LW223 as a TSPO-targeted PET radioligand. Pharmacol Res 2023; 189:106681. [PMID: 36746361 DOI: 10.1016/j.phrs.2023.106681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 01/12/2023] [Accepted: 01/30/2023] [Indexed: 02/05/2023]
Abstract
OBJECTIVES Translocator protein 18 kDa (TSPO) positron emission tomography (PET) can be harnessed for the non-invasive detection of macrophage-driven inflammation. [18F]LW223, a newly reported TSPO PET tracer which was insensitive to rs6971 polymorphism, showed favorable performance characteristics in a recent imaging study involving a rat myocardial infarction model. To enable quantitative neuroimaging with [18F]LW223, we conducted kinetic analysis in the non-human primate (NHP) brain. Further, we sought to assess the utility of [18F]LW223-based TSPO imaging in a first-in-human study. METHODS Radiosynthesis of [18F]LW223 was accomplished on an automated module, whereas molar activities, stability in formulation, lipophilicity and unbound free fraction (fu) of the probe were measured. Brain penetration and target specificity of [18F]LW223 in NHPs were corroborated by PET-MR imaging under baseline and pre-blocking conditions using the validated TSPO inhibitor, (R)-PK11195, at doses ranging from 5 to 10 mg/kg. Kinetic modeling was performed using one-tissue compartment model (1TCM), two-tissue compartment model (2TCM) and Logan graphical analyses, using dynamic PET data acquisition, arterial blood collection and metabolic stability testing. Clinical PET scans were performed in two healthy volunteers (HVs). Regional brain standard uptake value ratio (SUVr) was assessed for different time intervals. RESULTS [18F]LW223 was synthesized in non-decay corrected radiochemical yields (n.d.c. RCYs) of 33.3 ± 6.5% with molar activities ranging from 1.8 ± 0.7 Ci/µmol (n = 11). [18F]LW223 was stable in formulation for up to 4 h and LogD7.4 of 2.31 ± 0.13 (n = 6) and fu of 5.80 ± 1.42% (n = 6) were determined. [18F]LW223 exhibited good brain penetration in NHPs, with a peak SUV value of ca. 1.79 in the whole brain. Pre-treatment with (R)-PK11195 substantially accelerated the washout and attenuated the area under the time-activity curve, indicating in vivo specificity of [18F]LW223 towards TSPO. Kinetic modeling demonstrated that 2TCM was the most suitable model for [18F]LW223-based neuroimaging. Global transfer rate constants (K1) and total volumes of distribution (VT) were found to be 0.10 ± 0.01 mL/cm3/min and 2.30 ± 0.17 mL/cm3, respectively. Dynamic PET data analyses across distinct time windows revealed that the VT values were relatively stable after 60 min post-injection. In a preliminary clinical study with two healthy volunteers, [18F]LW223 exhibited good brain uptake and considerable tracer retention across all analyzed brain regions. Of note, an excellent correlation between SUVr with VT was obtained when assessing the time interval from 20 to 40 min post tracer injection (SUVr(20-40 min), R2 = 0.94, p < 0.0001), suggesting this time window may be suitable to estimate specific binding to TSPO in human brain. CONCLUSION Our findings indicate that [18F]LW223 is suitable for quantitative TSPO-targeted PET imaging in higher species. Employing state-of-the-art kinetic modeling, we found that [18F]LW223 was effective in mapping TSPO throughout the NHP brain, with best model fits obtained from 2TCM and Logan graphical analyses. Overall, our results indicate that [18F]LW223 exhibits favorable tracer performance characteristics in higher species, and this novel imaging tool may hold promise to provide effective neuroinflammation imaging in patients with neurological disease.
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Affiliation(s)
- Zhiqiang Tan
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Ahmed Haider
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Rd, Atlanta, GA 30322, USA
| | - Shaojuan Zhang
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Jiahui Chen
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Rd, Atlanta, GA 30322, USA
| | - Junjie Wei
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Kai Liao
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Guocong Li
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Huiyi Wei
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Chenchen Dong
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Wenqing Ran
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Ying Li
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Yuefeng Li
- Guangdong Landau Biotechnology Co. Ltd., Guangzhou 510555, China
| | - Jian Rong
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Rd, Atlanta, GA 30322, USA
| | - Yinlong Li
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Rd, Atlanta, GA 30322, USA
| | - Steven H Liang
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Rd, Atlanta, GA 30322, USA.
| | - Hao Xu
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China.
| | - Lu Wang
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China.
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Colussi G, Catena C, Darsiè D, Sechi LA. Benzodiazepines: An Old Class of New Antihypertensive Drugs? Am J Hypertens 2018; 31:402-404. [PMID: 29186312 DOI: 10.1093/ajh/hpx205] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Affiliation(s)
- GianLuca Colussi
- Clinica Medica, Department of Medicine, University of Udine, Udine, Italy
| | - Cristiana Catena
- Clinica Medica, Department of Medicine, University of Udine, Udine, Italy
| | - Daniele Darsiè
- Clinica Medica, Department of Medicine, University of Udine, Udine, Italy
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Abstract
The 3D structure of the 18-kDa transmembrane (TM) protein TSPO (translocator protein)/PBR (peripheral benzodiazepine receptor), which contains a binding site for benzodiazepines, is important to better understand its function and regulation by endogenous and synthetic ligands. We have recently determined the structure of mammalian TSPO/PBR in complex with the diagnostic ligand PK11195 [1-(2-chlorophenyl)-N-methyl-N-(1-methylpropyl)-3-isoquinolinecarboxamide; Jaremko et al. (2014) Science 343: , 1363-1366], providing for the first time atomic-level insight into the conformation of this protein, which is up-regulated in various pathological conditions including Alzheimer's disease and Parkinson's disease. Here, we review the studies which have probed the structural properties of mammalian TSPO/PBR as well as the homologues bacterial tryptophan-rich sensory proteins (TspOs) over the years and provide detailed insight into the 3D structure of mouse TSPO (mTSPO)/PBR in complex with PK11195.
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Guerin GF, Schmoutz CD, Goeders NE. The extra-adrenal effects of metyrapone and oxazepam on ongoing cocaine self-administration. Brain Res 2014; 1575:45-54. [PMID: 24887642 DOI: 10.1016/j.brainres.2014.05.039] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 05/20/2014] [Accepted: 05/25/2014] [Indexed: 11/30/2022]
Abstract
Investigation of the role of stress in cocaine addiction has yielded an efficacious combination of metyrapone and oxazepam, hypothesized to decrease relapse to cocaine use by reducing stress-induced craving. However, recent data suggest an extra-adrenal role for metyrapone in mediating stress- and addiction-related behaviors. The interactions between the physiological stress response and cocaine self-administration were characterized in rodents utilizing surgical adrenalectomy and pharmacological treatment. Male Wistar rats were trained to self-administer cocaine (0.25mg/kg/infusion) and food pellets under a concurrent alternating fixed-ratio schedule of reinforcement. Surgical removal of the adrenal glands resulted in a significant decrease in plasma corticosterone and a consequent increase in ACTH, as expected. However, adrenalectomy did not significantly affect ongoing cocaine self-administration. Pretreatment with metyrapone, oxazepam and their combinations in intact rats resulted in a significant decrease in cocaine-reinforced responses. These same pharmacological treatments were still effective in reducing cocaine- and food-reinforced responding in adrenalectomized rats. The results of these experiments demonstrate that adrenally-derived steroids are not necessary to maintain cocaine-reinforced responding in cocaine-experienced rats. These results also demonstrate that metyrapone may produce effects outside of the adrenal gland, presumably in the central nervous system, to affect cocaine-related behaviors.
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Affiliation(s)
- Glenn F Guerin
- Department of Pharmacology, Toxicology, & Neuroscience, Louisiana State University Health Sciences Center, 1501 Kings Highway, Box 33932, Shreveport, LA 71130, USA
| | - Christopher D Schmoutz
- Department of Pharmacology, Toxicology, & Neuroscience, Louisiana State University Health Sciences Center, 1501 Kings Highway, Box 33932, Shreveport, LA 71130, USA.
| | - Nicholas E Goeders
- Department of Pharmacology, Toxicology, & Neuroscience, Louisiana State University Health Sciences Center, 1501 Kings Highway, Box 33932, Shreveport, LA 71130, USA
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Abstract
Mitochondria are implicated in many important cellular functions covering the whole life cycle from mitochondrial biogenesis to cell death. Mitochondrial homeostasis is tightly regulated, and mitochondrial dysfunction is frequently associated with severe human pathologies (eg, cardiovascular diseases, cancer, and neurodegeneration). The permeability transition pore (PTP) is an unselective voltage-dependent mitochondrial channel. Despite the extensive use of electrophysiology, biochemistry, pharmacology, and genetic invalidation in mice, the molecular identity of PTP is still unknown. Nevertheless, PTP is central to mitochondrial vital functions and can play a lethal role in many pathophysiological conditions. This review recapitulates the current knowledge of the various modes of conductance of the PTP channel and discusses their implication in the physiological roles of PTP and their regulation. Based on its involvement in normal physiology and human pathology, a better understanding of this channel and its roles remains a major goal for basic scientists and clinicians.
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Affiliation(s)
- Catherine Brenner
- INSERM UMR-S 769, LabEx LERMIT, Université de Paris-Sud, 5, Rue JB Clément, 92296 Châtenay-Malabry, France.
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Kannan S, Saadani-Makki F, Balakrishnan B, Chakraborty P, Janisse J, Lu X, Muzik O, Romero R, Chugani DC. Magnitude of [(11)C]PK11195 binding is related to severity of motor deficits in a rabbit model of cerebral palsy induced by intrauterine endotoxin exposure. Dev Neurosci 2011; 33:231-40. [PMID: 21791891 DOI: 10.1159/000328125] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2010] [Accepted: 03/25/2011] [Indexed: 11/19/2022] Open
Abstract
Intrauterine inflammation is known to be a risk factor for the development of periventricular leukomalacia (PVL) and cerebral palsy. In recent years, activated microglial cells have been implicated in the pathogenesis of PVL and in the development of white matter injury. Clinical studies have shown the increased presence of activated microglial cells diffusely throughout the white matter in brains of patients with PVL. In vitro studies have reported that activated microglial cells induce oligodendrocyte damage and white matter injury by release of inflammatory cytokines, reactive nitrogen and oxygen species and the production of excitotoxic metabolites. PK11195 [1-(2-chlorophenyl)-N-methyl-N-(1-methylpropyl)-3-isoquinoline carboxamide] is a ligand that is selective for the 18-kDa translocator protein expressed on the outer mitochondrial membrane of activated microglia and macrophages. When labeled with carbon-11, [(11)C]PK11195 can effectively be used as a ligand in positron emission tomography (PET) studies for the detection of activated microglial cells in various neuroinflammatory and neurodegenerative conditions. In this study, we hypothesized that the magnitude of [(11)C]-(R)-PK11195 uptake in the newborn rabbit brain, as measured using a small-animal PET scanner, would match the severity of motor deficits resulting from intrauterine inflammation-induced perinatal brain injury. Pregnant New Zealand white rabbits were intrauterinely injected with endotoxin or saline at 28 days of gestation. Kits were born spontaneously at 31 days and underwent neurobehavioral testing and PET imaging following intravenous injection of the tracer [(11)C]-(R)-PK11195 on the day of birth. The neurobehavioral scores were compared with the change in [(11)C]PK11195 uptake over the time of scanning, for each of the kits. Upon analysis using receiver operating characteristic curves, an optimal combined sensitivity and specificity for detecting abnormal neurobehavioral scores suggestive of cerebral palsy in the neonatal rabbit was noted for a positive change in [(11)C]PK11195 uptake in the brain over time on PET imaging (sensitivity of 100% and area under the curve of >0.82 for all parameters tested). The strongest agreements were noted between a positive uptake slope - indicating increased [(11)C]PK11195 uptake over time - and worsening scores for measures of locomotion (indicated by hindlimb movement, forelimb movement, circular motion and straight- line motion; Cohen's κ >0.75 for each) and feeding (indicated by ability to suck and swallow and turn the head during feeding; Cohen's κ >0.85 for each). This was also associated with increased numbers of activated microglia (mean ratio ± SD of activated to total microglia: 0.96 ± 0.16 in the endotoxin group vs. 0.13 ± 0.08 in controls; p < 0.001) in the internal capsule and corona radiata. Our findings indicate that the magnitude of [(11)C]PK11195 binding measured in vivo by PET imaging matches the severity of motor deficits in the neonatal rabbit. Molecular imaging of ongoing neuroinflammation in the neonatal period may be helpful as a screening biomarker for detecting patients at risk of developing cerebral palsy due to a perinatal insult.
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Affiliation(s)
- Sujatha Kannan
- Department of Pediatrics, Wayne State University, Detroit, MI, USA.
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Kannan S, Balakrishnan B, Muzik O, Romero R, Chugani D. Positron emission tomography imaging of neuroinflammation. J Child Neurol 2009; 24:1190-9. [PMID: 19745091 PMCID: PMC3840908 DOI: 10.1177/0883073809338063] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Injury to the central nervous system is characterized by localization of activated microglia at the site of injury. The peripheral benzodiazepine receptor expressed on the outer mitochondrial membrane of the activated microglia is a sensitive biomarker for the detection of this neuroinflammatory response to an insult. PK11195, an isoquinoline ligand that specifically binds peripheral benzodiazepine receptor, can be tagged with a positron emitter and used as a tracer for molecular imaging of this receptor in vivo by positron emission tomography (PET). [(11)C](R)PK11195 has been used in the imaging of various neuroinflammatory disorders, such as Alzheimer disease and multiple sclerosis. On the basis of our small-animal PET imaging studies using a neonatal rabbit model of maternal inflammation-induced cerebral palsy, we propose that PET imaging using [(11)C](R)PK11195 may be a valuable tool for detecting neuroinflammation in the brain of newborns born to mothers with chorioamnionitis.
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Affiliation(s)
- Sujatha Kannan
- Carman and Ann Adams Department of Pediatrics, Wayne State University School of Medicine, Detroit, Michigan 48201, USA.
| | - Bindu Balakrishnan
- Carman and Ann Adams Department of Pediatrics, Wayne State University School of Medicine, Detroit, Michigan
| | - Otto Muzik
- Carman and Ann Adams Department of Pediatrics, Wayne State University School of Medicine, Detroit, Michigan,Department of Radiology, Wayne State University School of Medicine, Detroit, Michigan
| | - Roberto Romero
- Department of Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, Michigan,Perinatology Research Branch, NICHD, NIH, DHHS
| | - Diane Chugani
- Carman and Ann Adams Department of Pediatrics, Wayne State University School of Medicine, Detroit, Michigan,Department of Radiology, Wayne State University School of Medicine, Detroit, Michigan
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London SE, Remage-Healey L, Schlinger BA. Neurosteroid production in the songbird brain: a re-evaluation of core principles. Front Neuroendocrinol 2009; 30:302-14. [PMID: 19442685 PMCID: PMC2724309 DOI: 10.1016/j.yfrne.2009.05.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2009] [Revised: 05/01/2009] [Accepted: 05/04/2009] [Indexed: 11/17/2022]
Abstract
Concepts of brain-steroid signaling have traditionally placed emphasis on the gonads and adrenals as the source of steroids, the strict dichotomy of early developmental ("organizational") and mature ("activational") effects, and a relatively slow mechanism of signaling through intranuclear receptors. Continuing research shows that these concepts are not inaccurate, but they are certainly incomplete. In this review, we focus on the song control circuit of songbird species to demonstrate how each of these concepts is limited. We discuss the solid evidence for steroid synthesis within the brain ("neurosteroidogenesis"), the role of neurosteroids in organizational events that occur both early in development and later in life, and how neurosteroids can act in acute and non-traditional ways. The songbird model therefore illustrates how neurosteroids can dramatically increase the diversity of steroid-sensitive brain functions in a behaviorally-relevant system. We hope this inspires further research and thought into neurosteroid signaling in songbirds and other animals.
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Affiliation(s)
- Sarah E. London
- Institute for Genomic Biology, University of Illinois, Urbana-Champaign, Urbana, IL 61801
| | - Luke Remage-Healey
- Department of Physiological Science &, Ecology and Evolutionary Biology, Brain Research Institute, University of California, Los Angeles, Los Angeles, California 90095
| | - Barney A. Schlinger
- Department of Physiological Science &, Ecology and Evolutionary Biology, Brain Research Institute, University of California, Los Angeles, Los Angeles, California 90095
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11
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Disorders of folliculogenesis are associated with abnormal expression of peripheral benzodiazepine receptors in granulosa cells. Bull Exp Biol Med 2008; 145:29-32. [PMID: 19023995 DOI: 10.1007/s10517-008-0017-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
We studied apoptosis and expression of peripheral benzodiazepine receptors in granulosa cells of dominant follicles from women with endocrine sterility. The expression of peripheral benzodiazepine receptors in granulosa cells depends on the degree of granulosa cell apoptosis and type of disorders in follicular steroidogenesis, which suggests the involvement of peripheral benzodiazepine receptors into the regulation of folliculogenesis in health and disease.
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12
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de Faria DEP, Borges LV, Peters VM, Reis JEDP, Ribeiro LC, de Cássia da Silveira E Sá R, Guerra MDO. Postnatal development of pups from nursing rats treated with Gingko biloba. Phytother Res 2008; 22:185-9. [PMID: 17726727 DOI: 10.1002/ptr.2282] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The Gingko biloba extract is contraindicated during pregnancy and lactation due to the lack of information about its effects on these reproductive phases. Previous studies have shown that G. biloba extract contains components with estrogenic and antiestrogenic activities, thus nursing dams treated with the extract of this plant could show reduction in milk production, resulting in malnutrition and poor development of pups. This work analyzes the postnatal development of pups, whose mothers were treated with G. biloba extract during the lactation period. Nursing Wistar rats received 3.5 mg/kg/day of G. biloba aqueous extract, corresponding to the highest human dose. Clinical signs of maternal toxicity were evaluated. The growth rate, viability, survival during treatment and lactation indices of the pups were calculated. The physical, motor and sensorial development of the pups was also evaluated. No maternal signs of toxicity were observed. As there were no biological differences between control and G. biloba treated pups, it is possible to assume that, in this experimental design, the administration of G. biloba aqueous extract to nursing rats during the lactation period seems to be devoid of toxic effect to mothers and to the physical, motor and sensory development of the pups.
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Affiliation(s)
- Dieime Elaine Pereira de Faria
- Centro de Biologia da Reprodução, Universidade Federal de Juiz de Fora, caixa postal 328, CEP 36001-970, Juiz de Fora, MG, Brazil
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Giatzakis C, Batarseh A, Dettin L, Papadopoulos V. The role of Ets transcription factors in the basal transcription of the translocator protein (18 kDa). Biochemistry 2007; 46:4763-74. [PMID: 17402746 PMCID: PMC2529463 DOI: 10.1021/bi062208o] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The translocator protein (18 kDa; TSPO), previously known as peripheral-type benzodiazepine receptor, is a high-affinity cholesterol- and drug-binding mitochondrial protein involved in various cell functions including steroidogenesis, apoptosis, and proliferation. TSPO is highly expressed in secretory and glandular tissues, especially in steroidogenic cells, and its expression is altered in certain pathological conditions such as cancer and neurological diseases. In this study, we characterized the regulatory elements present in the region of the TPSO promoter extending from 515 to 805 bp upstream of the transcription start site, an area previously identified as being important for transcription. Promoter fragments extending 2.7 kb and 805 bp upstream of the transcription start site were able to direct enhanced green fluorescent protein expression to Leydig cells of the testis, theca cells of the ovary, and cells of the adrenal cortex in transgenic animals. This expression pattern perfectly mimicked endogenous TSPO expression. Functional characterization of the 515-805 bp region revealed the presence of one specificity protein 1/specificity protein 3 (Sp1/Sp3) and two v-ets erythroblastosis virus E26 oncogene homologue (Ets) binding sites that are important for transcriptional activity in both MA-10 mouse Leydig tumor cells and NIH/3T3 whole mouse embryo fibroblasts. GA-binding protein alpha (GABPalpha), a member of the Ets family of transcription factors, was found to be associated with the endogenous TSPO promoter. We conclude that Sp1/Sp3 and members of the Ets family of transcription factors bind to specific binding sites in the TSPO promoter to drive basal TSPO gene transcription.
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Affiliation(s)
| | | | | | - Vassilios Papadopoulos
- Address all correspondence and requests for reprints to: Dr. Vassilios Papadopoulos, Department of Biochemistry & Molecular and Cellular Biology, Georgetown University Medical Center, 3900 Reservoir Road NW, Washington, DC 20057. Tel: (202) 687-8991; Fax: (202) 687-7855; e-mail:
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14
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Effect of glutamate and somatostatin-14 on basal and cAMP-stimulated steroidogenesis by rainbow trout (Oncorhynchus mykiss) ovarian follicles, in vitro. Comp Biochem Physiol B Biochem Mol Biol 2005; 140:647-56. [PMID: 15763520 DOI: 10.1016/j.cbpc.2005.01.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2004] [Revised: 01/03/2005] [Accepted: 01/04/2005] [Indexed: 12/24/2022]
Abstract
The effects of glutamate and somatostatin-14 (SRIF) on the in vitro basal and cAMP-stimulated steroid production of mid-vitellogenic rainbow trout (Oncorhynchus mykiss) ovarian follicles were investigated. cAMP-stimulation was achieved by the addition of the adenylyl cyclase activator, forskolin (FS), or a membrane permeate cAMP agonist, 8-bromo-cAMP (BA), to the incubation medium. Testosterone (T) and 17beta-estradiol (E(2)) secretion was measured using radioimmunoassay. Solid phase extraction (SPE) was used to measure the relative formation of unconjugated and conjugated steroids, and high performance liquid chromatography (HPLC) was used to examine the steroid metabolites formed from the metabolism of a tritium labelled precursor, pregnenolone (P(5)). The accumulations of T and E(2) in the medium were suppressed in the presence of the glutamate agonists, N-methyl-d,l-aspartate (NMA) or l-glutamic acid (GA), and by the presence of SRIF. The suppression was evident for both basal and cAMP-stimulated steroidogenesis except for T concentrations of GA treatments following basal steroidogenesis, when there were no treatment effects. No significant effects of treatment on conjugated:unconjugated steroid ratios were found. For all treatments E(2) was the major end product steroid synthesized from P(5), and the steroid profiles were similar except for trace amounts of radiolabelled androgens in the medium following cAMP-stimulated steroidogenesis that were not present following basal steroidogenesis. The findings suggest that glutamate and SRIF reduce end point steroid production, possibly by reducing P(5) production. However, since the inhibitory affect was found for basal and cAMP-stimulated steroidogenesis, the response does not appear to be due to the inhibition of cAMP synthesis.
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15
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Mast N, Pikuleva IA. A simple and rapid method to measure cholesterol binding to P450s and other proteins. J Lipid Res 2005; 46:1561-8. [PMID: 15834119 DOI: 10.1194/jlr.d500008-jlr200] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cholesterol plays an important role in cellular function and membrane compartmentalization and is involved in the interaction with more than a dozen of different proteins. Using three cholesterol-metabolizing cytochrome P450s (P450s 7A1, 46A1, and 11A1), we have developed a rapid and simple assay for measurements of nanomolar to micromolar cholesterol affinities. In this assay, the P450 is incubated with a fixed amount of radiolabeled cholesterol and varying concentrations of cold cholesterol followed by separation of free and protein-bound cholesterol via filtration through a membrane. Free cholesterol is found in the flow-through fraction, whereas P450 binds to the membrane. The radioactivity of the membranes is then measured, and a saturation curve is generated after correction for nonspecific binding of cholesterol to the filter. The validity of the filter assay was confirmed by spectral assay, a traditional method to evaluate the interaction of the P450 enzymes with their substrates. Two types of membranes, one binding positively charged proteins and another binding negatively charged proteins, were identified. These membranes were also found to hold proteins through hydrophobic interactions. Thus, the cholesterol binding properties of a wide variety of proteins could be characterized using this filter assay.
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Affiliation(s)
- Natalia Mast
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston TX 77555-1031, USA
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16
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Villaseñor-García MM, Lozoya X, Osuna-Torres L, Viveros-Paredes JM, Sandoval-Ramírez L, Puebla-Pérez AM. Effect of Ginkgo biloba extract EGb 761 on the nonspecific and humoral immune responses in a hypothalamic-pituitary-adrenal axis activation model. Int Immunopharmacol 2005; 4:1217-22. [PMID: 15251117 DOI: 10.1016/j.intimp.2004.05.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2003] [Revised: 01/04/2004] [Accepted: 05/17/2004] [Indexed: 10/26/2022]
Abstract
We evaluated the immune response of healthy control and stressed Wistar rats submitted to hypothalamic-pituitary-adrenal (HPA) axis activation. Rats were treated with Ginkgo biloba extract (EGb 761) orally (100 mg/kg per day for 7 days). EGb 761 stimulated the digestion index of peritoneal and alveolar macrophages (PM and AM) of stressed rats. Likewise, the cellular immune response measured using the delayed-type hypersensitivity response to sheep red blood cells (SRBC) and the humoral immune response (measured through an anti-SRBC response), were also restored in stressed rats. Thus, this G. biloba extract possesses immunostimulatory activity in addition to its broad spectrum of pharmacological effects.
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Affiliation(s)
- María Martha Villaseñor-García
- Laboratorio de Inmunofarmacología de Productos Naturales, División de Medicina Molecular CIBO-IMSS, Guadalajara, Jalisco, Mexico.
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17
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Abstract
Tumor cell targeted therapies, by induction or enhancement of apoptosis, constitute recent promising approaches achieving more specific anti-tumor efficacy. The peripheral benzodiazepine receptor (PBR), which belongs to the permeability transition pore (PTP), the central regulatory complex of apoptosis, is a potential target. A number of findings argue in favor of the development of PBR targeting approaches: (i) overexpression of PBR has been described in a large range of human cancers, (ii) PTP-mediated regulation of programmed cell death is an apoptotic-inducing factor-independent check-point that could be modulated by various conventional cancer therapies, and (iii) PBR ligation enhances apoptosis induction in many types of tumors and reverses Bcl-2 cytoprotective effects. Altogether, these observations support the use of PBR-directed drugs, particularly PBR ligands such as Ro5-4864, in the treatment of human cancers.
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Affiliation(s)
- Didier Decaudin
- Department of Clinical Hematology, Institut Curie, Paris, France.
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18
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Giatzakis C, Papadopoulos V. Differential utilization of the promoter of peripheral-type benzodiazepine receptor by steroidogenic versus nonsteroidogenic cell lines and the role of Sp1 and Sp3 in the regulation of basal activity. Endocrinology 2004; 145:1113-23. [PMID: 14630713 DOI: 10.1210/en.2003-1330] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The peripheral-type benzodiazepine receptor (PBR) is involved in many cellular functions, including steroidogenesis, oxidative processes, cellular proliferation, and apoptosis. Secretory and glandular tissues, especially steroid hormone-producing cells, are particularly rich in PBR. To understand the mechanisms of PBR expression and regulation, we established an mRNA expression profile in mouse tissues and cell lines and subsequently mapped the transcription start site and characterized the promoter of the gene. Our findings indicate that PBR tissue mRNA levels are relatively high in kidney, spleen, muscle, lung, adrenal gland, thymus, and stomach; are intermediate in pancreas, uterus, prostate, heart, and testis; and are low in brain and liver. Relatively high levels of PBR mRNA were also observed in the steroid-synthesizing MA-10 mouse Leydig tumor cells compared with adrenocortical Y1 mouse cells and nonsteroidogenic NIH-3T3 mouse fibroblasts, although PBR protein levels were much higher in both steroidogenic cells compared with fibroblasts. Transcription was initiated primarily at an adenine nucleotide 61 nucleotides upstream of the translation start site, but internal initiation was also observed. A 2.7-kb fragment of the mouse PBR promoter was cloned and sequenced. Sequence analysis revealed the absence of TATA or CCAAT boxes, but the presence of many putative transcription factor-binding sites, including Sp1/Sp3, AP2, Ik2, AP1, SOX, GATA, and SRY. Functional characterization revealed that two Sp1/Sp3 sites in the proximal promoter are important for basal activity in all cell lines tested and that the steroidogenic MA-10 and Y1 cells use different areas of the promoter compared with nonsteroidogenic NIH-3T3 cells.
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Affiliation(s)
- Christoforos Giatzakis
- Department of Cell Biology, Georgetown University Medical Center, Washington, DC 20057, USA
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19
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Gesi M, Fornai F, Lenzi P, Ferrucci M, Soldani P, Ruffoli R, Paparelli A. Morphological alterations induced by loud noise in the myocardium: the role of benzodiazepine receptors. Microsc Res Tech 2002; 59:136-46. [PMID: 12373725 DOI: 10.1002/jemt.10186] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Noise represents an environmental stress factor affecting several organs and apparati, including the cardiovascular system. In experimental animals undergoing noise exposure, subcellular myocardial changes have been reported, especially at mitochondrial level; in particular, after 6 hours of exposure only the atrium exhibited significant mitochondrial alterations, whereas after 12 hours as well as subchronic exposure both atrium and ventricle were damaged. The first part of the present article overviews the experimental evidence on effects of noise on the myocardium. In the second part, the review analyzes the role of benzodiazepine receptors and the potential efficacy of benzodiazepine ligands in preventing the mitochondrial damage induced by noise exposure. Drugs acting at both central and peripheral benzodiazepine receptors significantly prevent this damage. Differences in the amount and the duration of the protective effect might depend on variability in the potency and pharmacokinetics of the specific drug. The effects of the combined treatment with selective and non-selective peripheral benzodiazepine ligands on noise stimulation are discussed at biochemical level reviewing studies on the effects of noise exposure on mitochondrial fractions.
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Affiliation(s)
- Marco Gesi
- Department of Human Morphology and Applied Biology, School of Medicine, University of Pisa, 56126 Pisa, Italy.
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20
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Boujrad N, Vidic B, Gazouli M, Culty M, Papadopoulos V. The peroxisome proliferator perfluorodecanoic acid inhibits the peripheral-type benzodiazepine receptor (PBR) expression and hormone-stimulated mitochondrial cholesterol transport and steroid formation in Leydig cells. Endocrinology 2000; 141:3137-48. [PMID: 10965884 DOI: 10.1210/endo.141.9.7678] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The peroxisome proliferator perfluordecanoic acid (PFDA) has been shown to exert an antiandrogenic effect in vivo by acting directly on the interstitial Leydig cells of the testis. The objective of this study was to examine the in vitro effects of PFDA and identify its site of action in steroidogenesis using as model systems the mouse tumor MA-10 and isolated rat Leydig cells. PFDA inhibited in a time- and dose-dependent manner the hCG-stimulated Leydig cell steroidogenesis. This effect was localized at the level of cholesterol transport into the mitochondria. PFDA did not affect either the total cell protein synthesis or the mitochondrial integrity. Moreover, it did not induce any DNA damage. Morphological studies indicated that PFDA induced lipid accumulation in the cells, probably due to the fact that cholesterol mobilized by hCG did not enter the mitochondria to be used for steroidogenesis. In search of the target of PFDA, we examined its effect on key regulatory mechanisms of steroidogenesis. PFDA did not affect the hCG-induced steroidogenic acute regulatory protein (StAR) levels. However, it was found to inhibit the mitochondrial peripheral-type benzodiazepine receptor (PBR) ligand binding capacity, 18-kDa protein, and messenger RNA (mRNA) levels. Further studies indicated that PFDA did not affect PBR transcription, but it rather accelerated PBR mRNA decay. Taken together, these data suggest that PFDA inhibits the Leydig cell steroidogenesis by affecting PBR mRNA stability, thus inhibiting PBR expression, cholesterol transport into the mitochondria, and the subsequent steroid formation. Moreover, this action of PFDA on PBR mRNA stability indicates a new mechanism of action of peroxisome proliferators distinct from the classic transcription-mediated regulation of target genes.
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Affiliation(s)
- N Boujrad
- Department of Cell Biology, Georgetown University Medical Center, Washington, DC 20007, USA
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21
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Salvetti F, Chelli B, Gesi M, Pellegrini A, Giannaccini G, Lucacchini A, Martini C. Effect of noise exposure on rat cardiac peripheral benzodiazepine receptors. Life Sci 2000; 66:1165-75. [PMID: 10737412 DOI: 10.1016/s0024-3205(00)00422-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Noise is an environmental physical agent, which is regarded as a stressful stimulus: impairment and modifications in biological functions are reported, after loud noise exposure, at several levels in human and animal organs and apparatuses, as well as in the endocrine, cardiovascular and nervous system. In the present study equilibrium binding parameters of peripheral benzodiazepine receptors (PBRs) labelled by the specific radioligand [3H]PK 11195, were evaluated in cardiac tissue of rats submitted to 6 or 12 h noise exposure and of rats treated "in vivo" with PBR ligands such as PK 11195, Ro54864, diazepam and then noise-exposed. Results revealed a statistically significant decrease in the maximum number of binding sites (Bmax) of [3H]PK 11195 in atrial membranes of 6 or 12 h noise exposed rats, compared with sham-exposed animals, without any change in the dissociation constant (Kd). The "in vivo" PBR ligand pre-treatment counteracted the noise-induced modifications of PBR density. As PBRs are mainly located on mitochondria we also investigated whether noise exposure can affect the [3H]PK 11195 binding parameters in isolated cardiac mitochondrial fractions. Results indicated a significant Bmax value decrease in right atrial mitochondrial fractions of rats 6 or 12 h noise-exposed. Furthermore, as PBR has been suggested to be a supramolecular complex that might coincide with the not-yet-established structure of the mitochondrial permeability transition (MPT)-pore, the status of the MPT-pore in isolated heart mitochondria was investigated in noise- and sham-exposed rats. The loss of absorbance associated with the calcium-induced MPT-pore opening was greater in mitochondria isolated from hearts of 6 h noise- than those of sham-exposed rats. In conclusion, these findings represent a further instance for PBR density decrease in response to a stressful stimulus, like noise; in addition they revealed that "in vivo" administration of PBR ligands significantly prevents this decrease. Finally, our data also suggest the involvement of MPT in the response of an organism to noise stress.
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Affiliation(s)
- F Salvetti
- Dipartimento di Psichiatria, Neurobiologia, Farmacologia e Biotecnologie, Università di Pisa, Italy
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22
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Giannaccini G, Betti L, Martini C, Bistocchi M, Mascia G, Piccolino M, Lucacchini A. Autoradiographic distribution of peripheral benzodiazepine receptors in the retina of the albino rabbit, Lepus cunicula. Neurosci Lett 2000; 280:37-40. [PMID: 10696806 DOI: 10.1016/s0304-3940(99)00982-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The distribution of peripheral benzodiazepine receptors (PBRs) in the retina of the albino rabbit, Lepus cunicula, was studied by autoradiography using [3H]-PK11195, a isoquinoline carboxamide, as a tracer. Autoradiograms obtained by directly placing the slides containing the retina sections on tritium-sensitive film provide evidence for the presence of PBRs in rabbit retina. Furthermore, the dark field examination of photomicrographs taken from autoradiograms showed two dense horizontal bands corresponding to the outer and inner photoreceptor segments, and to the inner plexiform layer. The retinal regions where [3H]-PK11195 binding was more dense are rich in mitochondria, suggesting that as in other neuronal tissues, retinal PBRs are involved in the mitochondrial activity.
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Affiliation(s)
- G Giannaccini
- Dipartimento di Psichiatria, Neurobiologia, Farmacologia e Biotecnologie dell'Università di Pisa, Italy
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