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Ksenofontov AL, Baratova LA, Semenyuk PI, Fedorova NV, Badun GA. Changes in the Structure of Potato Virus A Virions after Limited in situ Proteolysis According to Tritium Labeling Data and Computer Simulation. Biochemistry (Mosc) 2023; 88:2146-2156. [PMID: 38462457 DOI: 10.1134/s0006297923120167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 11/02/2023] [Accepted: 11/14/2023] [Indexed: 03/12/2024]
Abstract
Coat proteins (CP) of the potato virus A virions (PVA) contain partially disordered N-terminal domains, which are necessary for performing vital functions of the virus. Comparative analysis of the structures of coat proteins (CPs) in the intact PVA virions and in the virus particles lacking N-terminal 32 amino acids (PVAΔ32) was carried out in this work based on the tritium planigraphy data. Using atomic-resolution structure of the potato virus Y potyvirus (PVY) protein, which is a homolog of the CP PVA, the available CP surfaces in the PVY virion were calculated and the areas of intersubunit/interhelix contacts were determined. For this purpose, the approach of Lee and Richards [Lee, B., and Richards, F. M. (1971) J. Mol. Biol., 55, 379-400] was used. Comparison of incorporation profiles of the tritium label in the intact and trypsin-degraded PVAΔ32 revealed position of the ΔN-peptide shielding the surface domain (a.a. 66-73, 141-146) and the interhelix zone (a.a. 161-175) of the PVA CP. Presence of the channels/cavities was found in the virion, which turned out to be partially permeable to tritium atoms. Upon removal of the ΔN-peptide, decrease in the label incorporation within the virion (a.a. 184-200) was also observed, indicating possible structural transition leading to the virion compactization. Based on the obtained data, we can conclude that part of the surface ΔN-peptide is inserted between the coils of the virion helix thus increasing the helix pitch and providing greater flexibility of the virion, which is important for intercellular transport of the viruses in the plants.
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Affiliation(s)
- Alexander L Ksenofontov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia.
| | - Ludmila A Baratova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia
| | - Pavel I Semenyuk
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia
| | - Natalia V Fedorova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia
| | - Gennadii A Badun
- Faculty of Chemistry, Lomonosov Moscow State University, Moscow, 119991, Russia
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Arcanjo C, Frelon S, Armant O, Camoin L, Audebert S, Camilleri V, Cavalié I, Adam-Guillermin C, Gagnaire B. Insights into the modes of action of tritium on the early-life stages of zebrafish, Danio rerio, using transcriptomic and proteomic analyses. J Environ Radioact 2023; 261:107141. [PMID: 36878054 DOI: 10.1016/j.jenvrad.2023.107141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/29/2023] [Accepted: 02/17/2023] [Indexed: 06/18/2023]
Abstract
In the environment, populations are exposed to different kinds of ionizing radiation. Little is known about their modes of action on non-human species, and whether or not they are similar for alpha, beta and gamma radiations, considered as the reference. In this context, tritium effects (beta emitter) under the form of tritiated water (HTO) were investigated in zebrafish, a common model in toxicology and ecotoxicology with a fully sequenced genome. Experiments were conducted on early life stages, considered to be highly sensitive to pollutants, by exposing eggs to 0.4 mGy/h of HTO until 10 days post fertilization. Tritium internalization was quantified, and effects were investigated using a combined approach of transcriptomic and proteomic analyses. Results highlighted similarities in the biological pathways affected by HTO by both techniques, such as defence response, muscle integrity and contraction, and potential visual alterations. These results correlated well with previous data obtained on earlier developmental stages (1 and 4 dpf). Interestingly, HTO effects were partly overlapping those obtained after gamma irradiation, underlying potential common modes of action. This study, therefore, brought a body of evidence on the effects of HTO observed at the molecular level on zebrafish larvae. Further studies could investigate if the effects persist in adult organisms.
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Affiliation(s)
- Caroline Arcanjo
- Institut de Radioprotection et de Sureté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, Saint-Paul-lez-Durance, 13115, France
| | - Sandrine Frelon
- Institut de Radioprotection et de Sureté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, Saint-Paul-lez-Durance, 13115, France
| | - Olivier Armant
- Institut de Radioprotection et de Sureté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, Saint-Paul-lez-Durance, 13115, France
| | - Luc Camoin
- Aix-Marseille Univ., CNRS, INSERM, Institut Paoli-Calmettes, CRCM, Marseille Proteomics, Marseille, France
| | - Stéphane Audebert
- Aix-Marseille Univ., CNRS, INSERM, Institut Paoli-Calmettes, CRCM, Marseille Proteomics, Marseille, France
| | - Virginie Camilleri
- Institut de Radioprotection et de Sureté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, Saint-Paul-lez-Durance, 13115, France
| | - Isabelle Cavalié
- Institut de Radioprotection et de Sureté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, Saint-Paul-lez-Durance, 13115, France
| | - Christelle Adam-Guillermin
- Institut de Radioprotection et de Sureté Nucléaire (IRSN), PSE-SANTE/SDOS/LMDN, Cadarache, Saint-Paul-lez-Durance, 13115, France
| | - Beatrice Gagnaire
- Institut de Radioprotection et de Sureté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, Saint-Paul-lez-Durance, 13115, France.
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Lai JL, Li ZG, Wang Y, Xi HL, Luo XG. Tritium and Carbon-14 Contamination Reshaping the Microbial Community Structure, Metabolic Network, and Element Cycle in the Seawater Environment. Environ Sci Technol 2023; 57:5305-5316. [PMID: 36952228 DOI: 10.1021/acs.est.3c00422] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The potential ecological risks caused by entering radioactive wastewater containing tritium and carbon-14 into the sea require careful evaluation. This study simulated seawater's tritium and carbon-14 pollution and analyzed the effects on the seawater and sediment microenvironments. Tritium and carbon-14 pollution primarily altered nitrogen and phosphorus metabolism in the seawater environment. Analysis by 16S rRNA sequencing showed changes in the relative abundance of microorganisms involved in carbon, nitrogen, and phosphorus metabolism and organic matter degradation in response to tritium and carbon-14 exposure. Metabonomics and metagenomic analysis showed that tritium and carbon-14 exposure interfered with gene expression involving nucleotide and amino acid metabolites, in agreement with the results seen for microbial community structure. Tritium and carbon-14 exposure also modulated the abundance of functional genes involved in carbohydrate, phosphorus, sulfur, and nitrogen metabolic pathways in sediments. Tritium and carbon-14 pollution in seawater adversely affected microbial diversity, metabolic processes, and the abundance of nutrient-cycling genes. These results provide valuable information for further evaluating the risks of tritium and carbon-14 in marine environments.
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Affiliation(s)
- Jin-Long Lai
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China
| | - Zhan-Guo Li
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China
| | - Yi Wang
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China
| | - Hai-Ling Xi
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China
| | - Xue-Gang Luo
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, China
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Guo W, Wei J, Estillore JP, Zhang L, Wang R, Sun B, Chen SRW. RyR2 disease mutations at the C-terminal domain intersubunit interface alter closed-state stability and channel activation. J Biol Chem 2021; 297:100808. [PMID: 34022226 PMCID: PMC8214192 DOI: 10.1016/j.jbc.2021.100808] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 05/14/2021] [Accepted: 05/18/2021] [Indexed: 11/19/2022] Open
Abstract
Ryanodine receptors (RyRs) are ion channels that mediate the release of Ca2+ from the sarcoplasmic reticulum/endoplasmic reticulum, mutations of which are implicated in a number of human diseases. The adjacent C-terminal domains (CTDs) of cardiac RyR (RyR2) interact with each other to form a ring-like tetrameric structure with the intersubunit interface undergoing dynamic changes during channel gating. This mobile CTD intersubunit interface harbors many disease-associated mutations. However, the mechanisms of action of these mutations and the role of CTD in channel function are not well understood. Here, we assessed the impact of CTD disease-associated mutations P4902S, P4902L, E4950K, and G4955E on Ca2+− and caffeine-mediated activation of RyR2. The G4955E mutation dramatically increased both the Ca2+-independent basal activity and Ca2+-dependent activation of [3H]ryanodine binding to RyR2. The P4902S and E4950K mutations also increased Ca2+ activation but had no effect on the basal activity of RyR2. All four disease mutations increased caffeine-mediated activation of RyR2 and reduced the threshold for activation and termination of spontaneous Ca2+ release. G4955D dramatically increased the basal activity of RyR2, whereas G4955K mutation markedly suppressed channel activity. Similarly, substitution of P4902 with a negatively charged residue (P4902D), but not a positively charged residue (P4902K), also dramatically increased the basal activity of RyR2. These data suggest that electrostatic interactions are involved in stabilizing the CTD intersubunit interface and that the G4955E disease mutation disrupts this interface, and thus the stability of the closed state. Our studies shed new insights into the mechanisms of action of RyR2 CTD disease mutations.
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Affiliation(s)
- Wenting Guo
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada
| | - Jinhong Wei
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada
| | - John Paul Estillore
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada
| | - Lin Zhang
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada
| | - Ruiwu Wang
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada
| | - Bo Sun
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada; Medical School, Kunming University of Science and Technology, Kunming, China.
| | - S R Wayne Chen
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada.
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Jaumotte JD, Saarma M, Zigmond MJ. Protection of dopamine neurons by CDNF and neurturin variant N4 against MPP+ in dissociated cultures from rat mesencephalon. PLoS One 2021; 16:e0245663. [PMID: 33534843 PMCID: PMC7857574 DOI: 10.1371/journal.pone.0245663] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 01/05/2021] [Indexed: 01/27/2023] Open
Abstract
Parkinson's disease is associated with the loss of dopamine (DA) neurons in ventral mesencephalon. We have previously reported that no single neurotrophic factor we tested protected DA neurons from the dopaminergic toxin 1-methyl-4-phenylpyridinium (MPP+) in dissociated cultures isolated from the P0 rat substantia nigra, but that a combination of five neurotrophic factors was protective. We now report that cerebral DA neurotrophic factor (CDNF) and a variant of neurturin (NRTN), N4, were also not protective when provided alone but were protective when added together. In cultures isolated from the substantia nigra, MPP+ (10 μM) decreased tyrosine hydroxylase-positive cells to 41.7 ± 5.4% of vehicle control. Although treatment of cultures with 100 ng/ml of either CDNF or N4 individually before and after toxin exposure did not significantly increase survival in MPP+-treated cultures, when the two trophic factors were added together at 100 ng/ml each, survival of cells was increased 28.2 ± 6.1% above the effect of MPP+ alone. In cultures isolated from the ventral tegmental area, another DA rich area, a higher dose of MPP+ (1 mM) was required to produce an EC50 in TH-positive cells but, as in the substantia nigra, only the combination of CDNF and N4 (100 ng/ml each) was successful at increasing the survival of these cells compared to MPP+ alone (by 22.5 ± 3.5%). These data support previous findings that CDNF and N4 may be of therapeutic value for treatment of PD, but suggest that they may need to be administered together.
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Affiliation(s)
- Juliann D. Jaumotte
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, United States of America
- Pittsburgh Institute of Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Mart Saarma
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland
| | - Michael J. Zigmond
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, United States of America
- Pittsburgh Institute of Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, United States of America
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Peris-Yague A, Kiemes A, Cash D, Cotel MC, Singh N, Vernon AC, Modinos G. Region-specific and dose-specific effects of chronic haloperidol exposure on [ 3H]-flumazenil and [ 3H]-Ro15-4513 GABA A receptor binding sites in the rat brain. Eur Neuropsychopharmacol 2020; 41:106-117. [PMID: 33153853 PMCID: PMC7731940 DOI: 10.1016/j.euroneuro.2020.10.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 09/02/2020] [Accepted: 10/16/2020] [Indexed: 11/02/2022]
Abstract
Postmortem studies suggest that schizophrenia is associated with abnormal expression of specific GABAA receptor (GABAAR) α subunits, including α5GABAAR. Positron emission tomography (PET) measures of GABAAR availability in schizophrenia, however, have not revealed consistent alterations in vivo. Animal studies using the GABAAR agonist [3H]-muscimol provide evidence that antipsychotic drugs influence GABAAR availability, in a region-specific manner, suggesting a potential confounding effect of these drugs. No such data, however, are available for more recently developed subunit-selective GABAAR radioligands. To address this, we combined a rat model of clinically relevant antipsychotic drug exposure with quantitative receptor autoradiography. Haloperidol (0.5 and 2 mg/kg/day) or drug vehicle were administered continuously to adult male Sprague-Dawley rats via osmotic mini-pumps for 28 days. Quantitative receptor autoradiography was then performed postmortem using the GABAAR subunit-selective radioligand [3H]-Ro15-4513 and the non-subunit selective radioligand [3H]-flumazenil. Chronic haloperidol exposure increased [3H]-Ro15-4513 binding in the CA1 sub-field of the rat dorsal hippocampus (p<0.01; q<0.01; d=+1.3), which was not dose-dependent. [3H]-flumazenil binding also increased in most rat brain regions (p<0.05; main effect of treatment), irrespective of the haloperidol dose. These data confirm previous findings that chronic haloperidol exposure influences the specific binding of non-subtype selective GABAAR radioligands and is the first to demonstrate a potential effect of haloperidol on the binding of a α1/5GABAAR-selective radioligand. Although caution should be exerted when extrapolating results from animals to patients, our data support a view that exposure to antipsychotics may be a confounding factor in PET studies of GABAAR in the context of schizophrenia.
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Affiliation(s)
- Alba Peris-Yague
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, London SE5 8AF, United Kingdom
| | - Amanda Kiemes
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespingy Park, London SE5 8AF, United Kingdom
| | - Diana Cash
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, London SE5 8AF, United Kingdom
| | - Marie-Caroline Cotel
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, 5 Cutcombe Road, London SE5 9RT, United Kingdom
| | - Nisha Singh
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, London SE5 8AF, United Kingdom
| | - Anthony C Vernon
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, 5 Cutcombe Road, London SE5 9RT, United Kingdom; MRC Centre for Neurodevelopmental Disorders, King's College London, London, United Kingdom.
| | - Gemma Modinos
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, London SE5 8AF, United Kingdom; Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespingy Park, London SE5 8AF, United Kingdom; MRC Centre for Neurodevelopmental Disorders, King's College London, London, United Kingdom.
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Thamban Chandrika N, Fosso MY, Tsodikov OV, LeVine H, Garneau-Tsodikova S. Combining Chalcones with Donepezil to Inhibit Both Cholinesterases and Aβ Fibril Assembly. Molecules 2019; 25:E77. [PMID: 31878304 PMCID: PMC6983213 DOI: 10.3390/molecules25010077] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 12/18/2019] [Accepted: 12/21/2019] [Indexed: 02/08/2023] Open
Abstract
The fact that the number of people with Alzheimer's disease is increasing, combined with the limited availability of drugs for its treatment, emphasize the need for the development of novel effective therapeutics for treating this brain disorder. Herein, we focus on generating 12 chalcone-donepezil hybrids, with the goal of simultaneously targeting amyloid-β (Aβ) peptides as well as cholinesterases (i.e., acetylcholinesterase (AChE) and butyrylcholinesterase (BChE)). We present the design, synthesis, and biochemical evaluation of these two series of novel 1,3-chalcone-donepezil (15a-15f) or 1,4-chalcone-donepezil (16a-16f) hybrids. We evaluate the relationship between their structures and their ability to inhibit AChE/BChE activity as well as their ability to bind Aβ peptides. We show that several of these novel chalcone-donepezil hybrids can successfully inhibit AChE/BChE as well as the assembly of N-biotinylated Aβ(1-42) oligomers. We also demonstrate that the Aβ binding site of these hybrids differs from that of Pittsburgh Compound B (PIB).
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Affiliation(s)
- Nishad Thamban Chandrika
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596, USA; (N.T.C.); (M.Y.F.); (O.V.T.)
| | - Marina Y. Fosso
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596, USA; (N.T.C.); (M.Y.F.); (O.V.T.)
| | - Oleg V. Tsodikov
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596, USA; (N.T.C.); (M.Y.F.); (O.V.T.)
| | - Harry LeVine
- Center on Aging, School of Medicine, University of Kentucky, Lexington, KY 40536-0230, USA;
- Department of Molecular and Cellular Biochemistry, School of Medicine, University of Kentucky, Lexington, KY 40536-0230, USA
| | - Sylvie Garneau-Tsodikova
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596, USA; (N.T.C.); (M.Y.F.); (O.V.T.)
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Arcanjo C, Maro D, Camilleri V, Cavalié I, Simon O, Beaugelin-Seiller K, Carasco L, Orjollet D, Adam-Guillermin C, Gagnaire B. Assessing tritium internalisation in zebrafish early life stages: Importance of rapid isotopic exchange. J Environ Radioact 2019; 203:30-38. [PMID: 30849559 DOI: 10.1016/j.jenvrad.2019.02.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 01/22/2019] [Accepted: 02/19/2019] [Indexed: 06/09/2023]
Abstract
Tritium (3H) is mainly released into the environment in the form of tritiated water (HTO) by nuclear power plants and nuclear fuel reprocessing plants. To better understand how organisms may be affected by contamination to 3H it is essential to link observed effects to a correct estimation of absorbed dose rates. Due to quick isotopic exchanges between 3H and hydrogen, 3H measurement is difficult in small organisms such as zebrafish embryo, a model in ecotoxicological assay. This work aimed to optimise tritium measurement protocol to better characterise internalisation by early life stages of zebrafish. Zebrafish eggs were exposed at one HTO activity concentration of 1.22 × 105 Bq/mL. This activity was calculated to correspond to theoretical dose rates of 0.4 mGy/h, where some deleterious effects are expected on young fish. A protocol for the preparation of biological samples was adapted from the method classically used to segregate the different forms of tritium in organisms. To deal with very quick isotopic exchanges of 3H with hydrogen, the impacts of washing by non-tritiated water as well as the bias induced by absorbed tritium around organisms on the measured activity concentration were studied. We managed to develop protocols to perform total tritium and total organically bound tritium (OBT) activity concentrations measurements in zebrafish eggs and larvae. The measurement of these both forms allowed the calculation of tissue-free-water-tritium (TFWT). To better understand total tritium internalisation, a study of total tritium kinetics from 4 hpf (hour post-fertilization) to 168 hpf was performed. OBT and TFWT were also assessed to complete the total tritium internalisation kinetics. The internalisation is a rapid phenomenon reaching a steady-state within 24 h after the beginning of contamination for total tritium and TFWT, with concentration factors and TFWT/HTO close to unity. OBT formation seemed to be slower. It appeared that OBT content in organisms was low with an OBT/TFWT ratio of about 8% for both stages (24 hpf and 96 hpf). To verify absorbed dose rates at key developmental stages (24 hpf eggs and 96 hpf larvae), they were calculated from total tritium activity concentrations after exposure at 1.22 × 105 and 1.22 × 106 Bq/mL, as these two activity concentrations were used to assess effects of tritium in another part of the study. Dose rates calculated from total tritium activity concentrations measured in 24 hpf eggs and 96 hpf larvae were consistent with the nominal ones, which validates the robustness of the protocol developed in the present study.
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Affiliation(s)
- Caroline Arcanjo
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, 13115, Saint-Paul-lez-Durance, France.
| | - Denis Maro
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SRTE/LRC, Cherbourg-Octeville, 50130, France
| | - Virginie Camilleri
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, 13115, Saint-Paul-lez-Durance, France
| | - Isabelle Cavalié
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, 13115, Saint-Paul-lez-Durance, France
| | - Olivier Simon
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, 13115, Saint-Paul-lez-Durance, France
| | - Karine Beaugelin-Seiller
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, 13115, Saint-Paul-lez-Durance, France
| | - Loïc Carasco
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SRTE/LR2T, Cadarache, 13115, Saint-Paul-lez-Durance, France
| | - Daniel Orjollet
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SRTE/LR2T, Cadarache, 13115, Saint-Paul-lez-Durance, France
| | - Christelle Adam-Guillermin
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, 13115, Saint-Paul-lez-Durance, France
| | - Béatrice Gagnaire
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, 13115, Saint-Paul-lez-Durance, France
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Abstract
This protocol provides a comprehensive reference for the evolution of the lymph fistula model, the mechanism of lipid absorption, the detailed procedure for studying lipid absorption using the lymph fistula model, the interpretation of the results, and consideration of the experimental design. The lymph fistula model is an approach to assess the concentration and rate of a range of molecules transported by the lymph by cannulating lymph duct in animals. In this protocol, mice first undergo surgery with the implantation of cannulae in the duodenum and mesenteric lymph duct and are allowed to recover overnight in Bollman restraining cages housed in a temperature-regulated environment. To study in vivo lipid absorption, a lipid emulsion is prepared with labeled tracers, including [3 H]-triolein and [14 C]-cholesterol. On the day of the experiment, mice are continuously infused with lipid emulsion via the duodenum for 6 hr, and lymph is usually collected hourly. At the end of the study, gastrointestinal segments and their luminal contents are collected separately for determination of the digestion, uptake, and transport of exogenous lipids. © 2019 by John Wiley & Sons, Inc.
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Affiliation(s)
- Chih-Wei Ko
- Department of Pathology and Laboratory Medicine, University of Cincinnati, Cincinnati, Ohio 45237
| | - Jie Qu
- Department of Pathology and Laboratory Medicine, University of Cincinnati, Cincinnati, Ohio 45237
| | - Min Liu
- Department of Pathology and Laboratory Medicine, University of Cincinnati, Cincinnati, Ohio 45237
| | - Dennis D Black
- Children’s Foundation Research Institute at Le Bonheur Children’s Hospital, University of Tennessee Health Science Center, Memphis, Tennessee 38103
| | - Patrick Tso
- Department of Pathology and Laboratory Medicine, University of Cincinnati, Cincinnati, Ohio 45237
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Ivanov Kavkova E, Blöchl C, Tenhaken R. The Myo-inositol pathway does not contribute to ascorbic acid synthesis. Plant Biol (Stuttg) 2019; 21 Suppl 1:95-102. [PMID: 30102814 PMCID: PMC6492119 DOI: 10.1111/plb.12898] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 08/07/2018] [Indexed: 05/07/2023]
Abstract
Ascorbic acid (AsA) biosynthesis in plants predominantly occurs via a pathway with d-mannose and l-galactose as intermediates. One alternative pathway for AsA synthesis, which is similar to the biosynthesis route in mammals, is controversially discussed for plants. Here, myo-inositol is cleaved to glucuronic acid and then converted via l-gulonate to AsA. In contrast to animals, plants have an effective recycling pathway for glucuronic acid, being a competitor for the metabolic rate. Recycling involves a phosphorylation at C1 by the enzyme glucuronokinase. Two previously described T-DNA insertion lines in the gene coding for glucuronokinase1 show wild type-like expression levels of the mRNA in our experiments and do not accumulate glucuronic acid in labelling experiments disproving that these lines are true knockouts. As suitable T-DNA insertion lines were not available, we generated frameshift mutations in the major expressed isoform glucuronokinase1 (At3g01640) to potentially redirect metabolites to AsA. However, radiotracer experiments with 3 H-myo-inositol revealed that the mutants in glucuronokinase1 accumulate only glucuronic acid and incorporate less metabolite into cell wall polymers. AsA was not labelled, suggesting that Arabidopsis cannot efficiently use glucuronic acid for AsA biosynthesis. All four mutants in glucuronokinase as well as the wild type have the same level of AsA in leaves.
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Affiliation(s)
| | - C. Blöchl
- Department of BiosciencesUniversity of SalzburgSalzburgAustria
| | - R. Tenhaken
- Department of BiosciencesUniversity of SalzburgSalzburgAustria
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11
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Parsons TK, Pratt RN, Tang L, Wu Y. An active and selective molecular mechanism mediating the uptake of sex steroids by prostate cancer cells. Mol Cell Endocrinol 2018; 477:121-131. [PMID: 29928927 DOI: 10.1016/j.mce.2018.06.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 05/31/2018] [Accepted: 06/16/2018] [Indexed: 12/21/2022]
Abstract
Steroid hormones play important roles in normal physiological functions and diseases. Sex steroids hormones are important in the biology and treatment of sex hormone-related cancer such as prostate cancer and breast cancer. Cells may take up steroids using multiple mechanisms. The conventionally accepted hypothesis that steroids cross cell membrane through passive diffusion has not been tested rigorously. Experimental data suggested that cells may take up sex steroid using an active uptake mechanism. 3H-testosterone uptake by prostate cancer cells showed typical transporter-mediated uptake kinetic. Cells retained testosterone taken up from the medium. The uptake of testosterone was selective for certain steroid hormones but not others. Data also indicated that the active and selective uptake mechanism resided in cholesterol-rich membrane domains, and may involve ATP and membrane transporters. In summary, the present study provided strong evidence to support the existence of an active and selective molecular mechanism for sex steroid uptake.
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Affiliation(s)
- Todd K Parsons
- Department of Urology, Roswell Park Comprehensive Cancer Center, Elm and Carlton Streets, Buffalo, NY, 14263, USA
| | - Rachel N Pratt
- Department of Cancer Prevention and Control, Roswell Park Comprehensive Cancer Center, Elm and Carlton Streets, Buffalo, NY, 14263, USA
| | - Li Tang
- Department of Cancer Prevention and Control, Roswell Park Comprehensive Cancer Center, Elm and Carlton Streets, Buffalo, NY, 14263, USA
| | - Yue Wu
- Department of Urology, Roswell Park Comprehensive Cancer Center, Elm and Carlton Streets, Buffalo, NY, 14263, USA.
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12
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Pang Y, Thomas P. Progesterone induces relaxation of human umbilical cord vascular smooth muscle cells through mPRα (PAQR7). Mol Cell Endocrinol 2018; 474:20-34. [PMID: 29428395 DOI: 10.1016/j.mce.2018.02.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 02/05/2018] [Accepted: 02/05/2018] [Indexed: 02/07/2023]
Abstract
Progesterone effects on vascular smooth muscle cell (VSMC) relaxation and the mechanism were investigated in cultured human umbilical vein VSMCs. Membrane progesterone receptors mPRα, mPRβ, and mPRγ were highly expressed in VSMCs, whereas nuclear progesterone receptor (nPR) had low expression. Progesterone (20 nM) and 02-0 (mPR-selective agonist), but not R5020 (nPR agonist), induced muscle relaxation in both a VSMC collagen gel disk contraction assay and an endothelium-denuded human umbilical artery ring tension assay. Progesterone and 02-0 increased ERK and Akt phosphorylation and decreased cAMP levels. These effects were blocked by preincubation with pertussis toxin. Progestin-induced muscle relaxation was blocked by pretreatment with mPRα, but not nPR, siRNAs, and by co-treatment with 8-Br-cAMP, AZD6244 (MAP kinase inhibitor), and wortmannin (PI3K inhibitor). Progestins reduced myosin light chain phosphorylation which was blocked with AZD6244 and wortmannin. These results demonstrate progesterone directly relaxes human VSMCs through mPRα/Gi and MAP kinase/ERK-, Akt/PI3K-, and cAMP-dependent pathways.
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Affiliation(s)
- Yefei Pang
- Marine Science Institute, University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX, 78373, USA.
| | - Peter Thomas
- Marine Science Institute, University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX, 78373, USA.
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Varaschin RK, Allen NA, Rosenberg MJ, Valenzuela CF, Savage DD. Prenatal Alcohol Exposure Increases Histamine H 3 Receptor-Mediated Inhibition of Glutamatergic Neurotransmission in Rat Dentate Gyrus. Alcohol Clin Exp Res 2018; 42:295-305. [PMID: 29315624 PMCID: PMC5785429 DOI: 10.1111/acer.13574] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 11/28/2017] [Indexed: 01/08/2023]
Abstract
BACKGROUND We have reported that prenatal alcohol exposure (PAE)-induced deficits in dentate gyrus, long-term potentiation (LTP), and memory are ameliorated by the histamine H3 receptor inverse agonist ABT-239. Curiously, ABT-239 did not enhance LTP or memory in control offspring. Here, we initiated an investigation of how PAE alters histaminergic neurotransmission in the dentate gyrus and other brain regions employing combined radiohistochemical and electrophysiological approaches in vitro to examine histamine H3 receptor number and function. METHODS Long-Evans rat dams voluntarily consumed either a 0% or 5% ethanol solution 4 hours each day throughout gestation. This pattern of drinking, which produces a mean peak maternal serum ethanol concentration of 60.8 ± 5.8 mg/dl, did not affect maternal weight gain, litter size, or offspring birthweight. RESULTS Radiohistochemical studies in adult offspring revealed that specific [3 H]-A349821 binding to histamine H3 receptors was not different in PAE rats compared to controls. However, H3 receptor-mediated Gi /Go protein-effector coupling, as measured by methimepip-stimulated [35 S]-GTPγS binding, was significantly increased in cerebral cortex, cerebellum, and dentate gyrus of PAE rats compared to control. A LIGAND analysis of detailed methimepip concentration-response curves in dentate gyrus indicated that PAE significantly elevates receptor-effector coupling by a lower affinity H3 receptor population without significantly altering the affinities of H3 receptor subpopulations. In agreement with the [35 S]-GTPγS studies, a similar range of methimepip concentrations also inhibited electrically evoked field excitatory postsynaptic potential responses and increased paired-pulse ratio, a measure of decreased glutamate release, to a significantly greater extent in dentate gyrus slices from PAE rats than in controls. CONCLUSIONS These results suggest that a PAE-induced elevation in H3 receptor-mediated inhibition of glutamate release from perforant path terminals as 1 mechanism contributing the LTP deficits previously observed in the dentate gyrus of PAE rats, as well as providing a mechanistic basis for the efficacy of H3 receptor inverse agonists for ameliorating these deficits.
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Affiliation(s)
- Rafael K Varaschin
- Department of Neurosciences, University of New Mexico School of Medicine, Albuquerque, New Mexico, 87131
| | - Nyika A Allen
- Department of Neurosciences, University of New Mexico School of Medicine, Albuquerque, New Mexico, 87131
| | - Martina J Rosenberg
- Department of Neurosciences, University of New Mexico School of Medicine, Albuquerque, New Mexico, 87131
| | - C Fernando Valenzuela
- Department of Neurosciences, University of New Mexico School of Medicine, Albuquerque, New Mexico, 87131
| | - Daniel D Savage
- Department of Neurosciences, University of New Mexico School of Medicine, Albuquerque, New Mexico, 87131
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Haque S, Whittaker M, McIntosh MP, Pouton CW, Phipps S, Kaminskas LM. A comparison of the lung clearance kinetics of solid lipid nanoparticles and liposomes by following the 3H-labelled structural lipids after pulmonary delivery in rats. Eur J Pharm Biopharm 2018; 125:1-12. [PMID: 29309835 DOI: 10.1016/j.ejpb.2018.01.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 11/16/2017] [Accepted: 01/04/2018] [Indexed: 12/31/2022]
Abstract
The utility of biodegradable nanosized drug carriers for the local and controlled delivery of therapeutics to the lungs has prompted significant interest in the development of inhalable nanomedicines. Still, little is known about how these systems are cleared from the lungs, including the kinetics of the structural lipids. Most preclinical and clinical studies to date have evaluated the lung clearance of loaded drugs, which in many cases poorly reflects the kinetics of the nanocarrier, or the bulk-labelled particles. This study therefore aimed to describe and compare the pulmonary pharmacokinetic behaviour and patterns of lung clearance of two commonly explored inhalable nanocarriers (anionic ∼150 nm liposomes and solid lipid nanoparticles [SLNs]) in rats by following the 3H-labelled structural lipids (phosphatidylcholine and tristearin respectively). The data showed that SLNs and liposomes were cleared from the lungs at similar rates, despite SLNs being deposited after intratracheal instillation in the upper respiratory track, and primarily via the mucociliary escalator, but this process was more pronounced for SLNs. Structural lipids were mainly associated with plasma proteins rather than nanocarrier in plasma. The lipids also exhibit prolonged lung exposure and are associated with the lung tissue (rather than BALF) over 2 weeks.
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Affiliation(s)
- Shadabul Haque
- Drug Delivery Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Pde, Parkville, VIC 3052, Australia; ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Melbourne, VIC 3052, Australia
| | - Michael Whittaker
- Drug Delivery Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Pde, Parkville, VIC 3052, Australia; ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Melbourne, VIC 3052, Australia
| | - Michelle P McIntosh
- Drug Delivery Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Pde, Parkville, VIC 3052, Australia
| | - Colin W Pouton
- Drug Delivery Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Pde, Parkville, VIC 3052, Australia
| | - Simon Phipps
- School of Biomedical Sciences, University of Queensland, St Lucia, QLD 4072, Australia
| | - Lisa M Kaminskas
- Drug Delivery Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Pde, Parkville, VIC 3052, Australia; School of Biomedical Sciences, University of Queensland, St Lucia, QLD 4072, Australia.
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Abstract
In this chapter, we present the preparation of gangliosides isotopically labelled with 3H or 14C. The methods do not present specific difficulties and can be used in any radiochemical laboratory. Some procedures can be applied to both gangliosides and neutral glycosphingolipids.
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Affiliation(s)
- Laura Mauri
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Simona Prioni
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Maria Grazia Ciampa
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Sandro Sonnino
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy.
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Shukla D, Mandal PK, Ersland L, Grüner ER, Tripathi M, Raghunathan P, Sharma A, Chaithya G, Punjabi K, Splaine C. A Multi-Center Study on Human Brain Glutathione Conformation using Magnetic Resonance Spectroscopy. J Alzheimers Dis 2018; 66:517-532. [PMID: 30198874 PMCID: PMC6218146 DOI: 10.3233/jad-180648] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/17/2018] [Indexed: 12/14/2022]
Abstract
Molecular dynamics simulation and in vitro nuclear magnetic resonance (NMR) studies on glutathione (GSH) indicated existence of closed and extended conformations. The present work in a multi-center research setting reports in-depth analysis of GSH conformers in vivo using a common magnetic resonance spectroscopy (MRS) protocol and signal processing scheme. MEGA-PRESS pulse sequence was applied on healthy subjects using 3T Philips MRI scanner (India) and 3T GE MRI scanner (Norway) using the same experimental parameters (echo time, repetition time, and selective 180° refocusing ON-pulse at 4.40 ppm and 4.56 ppm). All MRS data were processed at one site National Brain Research Center (NBRC) using in-house MRS processing toolbox (KALPANA) for consistency. We have found that both the closed and extended GSH conformations are present in human brain and the relative proportion of individual conformer peak depends on the specific selection of refocusing ON-pulse position in MEGA-PRESS pulse sequence. It is important to emphasize that in vivo experiments with different refocusing and inversion pulse positions, echo time, and voxel size, clearly evidence the presence of both the GSH conformations. The GSH conformer peak positions for the closed GSH (Cys-Hβ) peak at ∼2.80 ppm and extended GSH (Cys-Hβ) peak at ∼2.95 ppm remain consistent irrespective of the selective refocusing OFF-pulse positions. This is the first in vivo study where both extended and closed GSH conformers are detected using the MEGA-PRESS sequence employing the parameters derived from the high resolution in vitro NMR studies on GSH.
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Affiliation(s)
- Deepika Shukla
- Neuroimaging and Neurospectroscopy Laboratory (NINS), National Brain Research Centre, Gurgaon, India
| | - Pravat K. Mandal
- Neuroimaging and Neurospectroscopy Laboratory (NINS), National Brain Research Centre, Gurgaon, India
- The Florey Institute of Neuroscience and Mental Health, Melbourne, VIC, Australia
| | - Lars Ersland
- Department of Clinical Engineering, Haukeland University Hospital, Bergen, Norway
- Department of Biological and Medical Psychology, University of Bergen, Norway
- NORMENT Center of Excellence, University of Oslo, Norway
| | - Eli Renate Grüner
- NORMENT Center of Excellence, University of Oslo, Norway
- Department of Clinical Radiology, Haukeland University Hospital, Bergen, Norway
- Department of Physics and Technology, University of Bergen, Norway
| | - Manjari Tripathi
- Department of Neurology, All India Institute of Medical Sciences, New Delhi, India
| | | | - Ankita Sharma
- Neuroimaging and Neurospectroscopy Laboratory (NINS), National Brain Research Centre, Gurgaon, India
| | - G.R. Chaithya
- Neuroimaging and Neurospectroscopy Laboratory (NINS), National Brain Research Centre, Gurgaon, India
| | - Khushboo Punjabi
- Neuroimaging and Neurospectroscopy Laboratory (NINS), National Brain Research Centre, Gurgaon, India
| | - Christopher Splaine
- Department of Chemistry, Case Western Reserve University, Cleveland, OH, USA
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17
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Hamedani H, Kadlecek S, Xin Y, Siddiqui S, Gatens H, Naji J, Ishii M, Cereda M, Rossman M, Rizi R. A hybrid multibreath wash-in wash-out lung function quantification scheme in human subjects using hyperpolarized 3 He MRI for simultaneous assessment of specific ventilation, alveolar oxygen tension, oxygen uptake, and air trapping. Magn Reson Med 2017; 78:611-624. [PMID: 27734519 PMCID: PMC5391315 DOI: 10.1002/mrm.26401] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 08/03/2016] [Accepted: 08/08/2016] [Indexed: 01/06/2023]
Abstract
PURPOSE To present a method for simultaneous acquisition of alveolar oxygen tension (PA O2 ), specific ventilation (SV), and apparent diffusion coefficient (ADC) of hyperpolarized (HP) gas in the human lung, allowing reinterpretation of the PA O2 and SV maps to produce a map of oxygen uptake (R). METHOD An imaging scheme was designed with a series of identical normoxic HP gas wash-in breaths to measure ADC, SV, PA O2 , and R in less than 2 min. Signal dynamics were fit to an iterative recursive model that regionally solved for these parameters. This measurement was successfully performed in 12 subjects classified in three healthy, smoker, and chronic obstructive pulmonary disease (COPD) cohorts. RESULTS The overall whole lung ADC, SV, PA O2 , and R in healthy, smoker, and COPD subjects was 0.20 ± 0.03 cm2 /s, 0.39 ± 0.06,113 ± 2 Torr, and 1.55 ± 0.35 Torr/s, respectively, in healthy subjects; 0.21 ± 0.03 cm2 /s, 0.33 ± 0.06, 115.9 ± 4 Torr, and 0.97 ± 0.2 Torr/s, respectively, in smokers; and 0.25 ± 0.06 cm2 /s, 0.23 ± 0.08, 114.8 ± 6.0Torr, and 0.94 ± 0.12 Torr/s, respectively, in subjects with COPD. Hetrogeneity of SV, PA O2 , and R were indicators of both smoking-related changes and disease, and the severity of the disease correlated with the degree of this heterogeneity. Subjects with symptoms showed reduced oxygen uptake and specific ventilation. CONCLUSION High-resolution, nearly coregistered and quantitative measures of lung function and structure were obtained with less than 1 L of HP gas. This hybrid multibreath technique produced measures of lung function that revealed clear differences among the cohorts and subjects and were confirmed by correlations with global lung measurements. Magn Reson Med 78:611-624, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Hooman Hamedani
- Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States
| | - Stephen Kadlecek
- Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States
| | - Yi Xin
- Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States
| | - Sarmad Siddiqui
- Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States
| | - Heather Gatens
- Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States
| | - Joseph Naji
- Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States
| | - Masaru Ishii
- Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States
- Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins University, Baltimore, Maryland, USA
| | - Maurizio Cereda
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA, United States
| | - Milton Rossman
- Pulmonary, Allergy and Critical Care Division, University of Pennsylvania, Philadelphia, PA, United States
| | - Rahim Rizi
- Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States
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18
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Taher M, Amiroudine MZAM, Jaffri JM, Amri MS, Susanti D, Abd Hamid S, Rezali MF, Hassan CM, Read RW, Ahmed Q, Ahmad F. A lignan with glucose uptake activity in 3T3-L1 adipocytes from the stem bark of Knema patentinervia. Pak J Pharm Sci 2017; 30:1335-1339. [PMID: 29039334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A new naturally occurring dibenzylbutyrolactone lignan named isocubebinic ether has been isolated from Knema patentinervia. The structure was established by spectroscopic methods, which include Ultraviolet, Infrared, Nuclear Magnetic Resonance and Mass Spectrometry. The compound showed activity in the stimulation of glucose uptake by 3T3-L1 adipocytes.
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Affiliation(s)
- Muhammad Taher
- Department of Pharmaceutical Technology, Faculty of Pharmacy, International Islamic University Malaysia, Jalan Istana, Bandar Indera Mahkota, Kuantan, Pahang, Malaysia
| | - Mohamed Zaffar Ali Mohamed Amiroudine
- Department of Pharmaceutical Technology, Faculty of Pharmacy, International Islamic University Malaysia, Jalan Istana, Bandar Indera Mahkota, Kuantan, Pahang, Malaysia
| | - Juliana Md Jaffri
- Department of Pharmaceutical Technology, Faculty of Pharmacy, International Islamic University Malaysia, Jalan Istana, Bandar Indera Mahkota, Kuantan, Pahang, Malaysia
| | - Mohamad Shahreen Amri
- Department of Pharmaceutical Technology, Faculty of Pharmacy, International Islamic University Malaysia, Jalan Istana, Bandar Indera Mahkota, Kuantan, Pahang, Malaysia
| | - Deny Susanti
- Department of Chemistry, Faculty of Science, International Islamic University Malaysia, Jalan Istana, Bandar Indera Mahkota, Kuantan, Pahang, Malaysia
| | - Shafida Abd Hamid
- Department of Chemistry, Faculty of Science, International Islamic University Malaysia, Jalan Istana, Bandar Indera Mahkota, Kuantan, Pahang, Malaysia
| | - Mohamad Fazlin Rezali
- SIRIM Berhad (National Metrology Laboratory), Lot PT, Bandar Baru Salak Tinggi, Sepang, Selangor, Malaysia
| | | | - Roger W Read
- The School of Chemistry, The University of New South Wales, UNSW Sydney NSW, Australia
| | - Qamaruddin Ahmed
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, International Islamic University Malaysia, Jalan Istana, Bandar Indera Mahkota, Kuantan, Pahang, Malaysia
| | - Farediah Ahmad
- Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, Skudai, Johor, Malaysia
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Adams RM, Wang M, Crane AM, Brown B, Darlington GJ, Ledley FD. Effective Cryopreservation and Long-Term Storage of Primary Human Hepatocytes with Recovery of Viability, Differentiation, and Replicative Potential. Cell Transplant 2017; 4:579-86. [PMID: 8714779 DOI: 10.1177/096368979500400607] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Despite reports of successful cryopreservation of primary human hepatocytes, existing methods do not produce sufficient recovery of viable cells to meet the needs of basic research or clinical trials of hepatocellular transplantation. We now describe a protocol for efficient cryopreservation of primary human hepatocytes using University of Wisconsin (UW) solution, fetal bovine serum, and dimethyl sulfoxide (DMSO). This method provides >90% viability of differentiated, primary human hepatocytes 8 mo after cryopreservation as measured by trypan blue exclusion, preserves hepatocyte morphology, liver-specific gene expression α1 antitrypsin), and replication. The effectiveness of UW solution as a cryopreservative agent suggests that metabolic as well as ultrastructural factors may be important in the effective cryopreservation of primary human hepatocytes. The present method represents an effective protocol for cryopreserving differentiated primary human hepatocytes for research. This method may allow characterization and banking of human hepatocytes for clinical applications, including hepatocellular transplantation and hepatic assist devices.
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Affiliation(s)
- R M Adams
- Department of Cell Biology, Baylor College of Medicine, Houston, TX 77030, USA
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20
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Thomas P, Pang Y, Dong J. Membrane androgen receptor characteristics of human ZIP9 (SLC39A) zinc transporter in prostate cancer cells: Androgen-specific activation and involvement of an inhibitory G protein in zinc and MAP kinase signaling. Mol Cell Endocrinol 2017; 447:23-34. [PMID: 28219737 DOI: 10.1016/j.mce.2017.02.025] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 02/14/2017] [Accepted: 02/14/2017] [Indexed: 11/29/2022]
Abstract
Characteristics of novel human membrane androgen receptor (mAR), ZIP9 (SLC39A9), were investigated in ZIP9-transfected PC-3 cells (PC3-ZIP9). Ligand blot analysis showed plasma membrane [3H]-T binding corresponds to the position of ZIP9 on Western blots which suggests ZIP9 can bind [3H]-T alone, without a protein partner. Progesterone antagonized testosterone actions, blocking increases in zinc, Erk phosphorylation and apoptosis, further evidence that ZIP9 is specifically activated by androgens. Pre-treatment with GTPγS and pertussis toxin decreased plasma membrane [3H]-T binding and blocked testosterone-induced increases in Erk phosphorylation and intracellular zinc, indicating ZIP9 is coupled to an inhibitory G protein (Gi) that mediates both MAP kinase and zinc signaling. Testosterone treatment of nuclei and mitochondria which express ZIP9 decreased their zinc contents, suggesting ZIP9 also regulates free zinc through releasing it from these intracellular organelles. The results show ZIP9 is a specific Gi coupled-mAR mediating testosterone-induced MAP kinase and zinc signaling in PC3-ZIP9 cells.
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Affiliation(s)
- Peter Thomas
- University of Texas Marine Science Institute, 750 Channel View Drive, Port Aransas, TX, 78373, USA.
| | - Yefei Pang
- University of Texas Marine Science Institute, 750 Channel View Drive, Port Aransas, TX, 78373, USA
| | - Jing Dong
- University of Texas Marine Science Institute, 750 Channel View Drive, Port Aransas, TX, 78373, USA
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Date SS, Fiori MC, Altenberg GA, Jansen M. Expression in Sf9 insect cells, purification and functional reconstitution of the human proton-coupled folate transporter (PCFT, SLC46A1). PLoS One 2017; 12:e0177572. [PMID: 28493963 PMCID: PMC5426777 DOI: 10.1371/journal.pone.0177572] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 04/28/2017] [Indexed: 01/05/2023] Open
Abstract
The proton-coupled folate transporter (PCFT) provides an essential uptake route for the vitamin folic acid (B9) in mammals. In addition, it is currently of high interest for targeting chemotherapeutic agents to tumors due to the increased folic acid requirement of rapidly dividing tumor cells as well as the upregulated PCFT expression in several tumors. To understand its function, determination of its atomic structure and molecular mechanism of transport are essential goals that require large amounts of functional PCFT. Here, we present a high-level heterologous expression system for human PCFT using a recombinant baculovirus and Spodoptera frugiperda (Sf9) insect cells. We demonstrate folate transport functionality along the PCFT expression, isolation, and purification process. Importantly, purified PCFT transports folic acid after reconstitution. We thus succeeded in overcoming heterologous expression as a major bottleneck of PCFT research. The availability of an overexpression system for human PCFT provides the basis for future biochemical, biophysical and structural studies.
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Affiliation(s)
- Swapneeta S. Date
- Department of Cell Physiology and Molecular Biophysics, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States of America
- Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States of America
| | - Mariana C. Fiori
- Department of Cell Physiology and Molecular Biophysics, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States of America
- Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States of America
| | - Guillermo A. Altenberg
- Department of Cell Physiology and Molecular Biophysics, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States of America
- Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States of America
| | - Michaela Jansen
- Department of Cell Physiology and Molecular Biophysics, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States of America
- Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States of America
- * E-mail:
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Melintescu A, Galeriu D. Uncertainty of current understanding regarding OBT formation in plants. J Environ Radioact 2017; 167:134-149. [PMID: 27916298 DOI: 10.1016/j.jenvrad.2016.11.026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 11/17/2016] [Accepted: 11/25/2016] [Indexed: 06/06/2023]
Abstract
Radiological impact models are important tools that support nuclear safety. For tritium, a special radionuclide that readily enters the life cycle, the processes involved in its transport into the environment are complex and inadequately understood. For example, tritiated water (HTO) enters plants by leaf and root uptake and is converted to organically bound tritium (OBT) in exchangeable and non-exchangeable forms; however, the observed OBT/HTO ratios in crops exhibit large variability and contradict the current models for routine releases. Non-routine or spike releases of tritium further complicate the prediction of OBT formation. The experimental data for a short and intense atmospheric contamination of wheat are presented together with various models' predictions. The experimental data on wheat demonstrate that the OBT formation is a long process, it is dependent on receptor location and stack dynamics, there are differences between night and day releases, and the HTO dynamics in leaf and ear is a very important contributor to OBT formation.
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Affiliation(s)
- A Melintescu
- "Horia Hulubei" National Institute for Physics and Nuclear Engineering, Department of Life and Environmental Physics, 30 Reactorului St., P.O. Box MG-6, Bucharest - Magurele, RO-077125, Romania.
| | - D Galeriu
- "Horia Hulubei" National Institute for Physics and Nuclear Engineering, Department of Life and Environmental Physics, 30 Reactorului St., P.O. Box MG-6, Bucharest - Magurele, RO-077125, Romania
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23
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Marquié M, Normandin MD, Meltzer AC, Chong MST, Andrea NV, Antón-Fernández A, Klunk WE, Mathis CA, Ikonomovic MD, Debnath M, Bien EA, Vanderburg CR, Costantino I, Makaretz S, DeVos SL, Oakley DH, Gomperts SN, Growdon JH, Domoto-Reilly K, Lucente D, Dickerson BC, Frosch MP, Hyman BT, Johnson KA, Gómez-Isla T. Pathological correlations of [F-18]-AV-1451 imaging in non-alzheimer tauopathies. Ann Neurol 2017; 81:117-128. [PMID: 27997036 PMCID: PMC5319193 DOI: 10.1002/ana.24844] [Citation(s) in RCA: 157] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 11/08/2016] [Accepted: 12/04/2016] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Recent studies have shown that positron emission tomography (PET) tracer AV-1451 exhibits high binding affinity for paired helical filament (PHF)-tau pathology in Alzheimer's brains. However, the ability of this ligand to bind to tau lesions in other tauopathies remains controversial. Our goal was to examine the correlation of in vivo and postmortem AV-1451 binding patterns in three autopsy-confirmed non-Alzheimer tauopathy cases. METHODS We quantified in vivo retention of [F-18]-AV-1451 and performed autoradiography, [H-3]-AV-1451 binding assays, and quantitative tau measurements in postmortem brain samples from two progressive supranuclear palsy (PSP) cases and a MAPT P301L mutation carrier. They all underwent [F-18]-AV-1451 PET imaging before death. RESULTS The three subjects exhibited [F-18]-AV-1451 in vivo retention predominantly in basal ganglia and midbrain. Neuropathological examination confirmed the PSP diagnosis in the first two subjects; the MAPT P301L mutation carrier had an atypical tauopathy characterized by grain-like tau-containing neurites in gray and white matter with heaviest burden in basal ganglia. In all three cases, autoradiography failed to show detectable [F-18]-AV-1451 binding in multiple brain regions examined, with the exception of entorhinal cortex (reflecting incidental age-related neurofibrillary tangles) and neuromelanin-containing neurons in the substantia nigra (off-target binding). The lack of a consistent significant correlation between in vivo [F-18]-AV-1541 retention and postmortem in vitro binding and tau measures in these cases suggests that this ligand has low affinity for tau lesions primarily made of straight tau filaments. INTERPRETATION AV-1451 may have limited utility for in vivo selective and reliable detection of tau aggregates in these non-Alzheimer tauopathies. ANN NEUROL 2017;81:117-128.
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Affiliation(s)
- Marta Marquié
- MassGeneral Institute for NeuroDegenerative Disease, Charlestown, MA
- Department of Neurology, Massachusetts General Hospital, Boston, MA
| | | | - Avery C. Meltzer
- MassGeneral Institute for NeuroDegenerative Disease, Charlestown, MA
- Department of Neurology, Massachusetts General Hospital, Boston, MA
| | - Michael Siao Tick Chong
- MassGeneral Institute for NeuroDegenerative Disease, Charlestown, MA
- Department of Neurology, Massachusetts General Hospital, Boston, MA
| | | | | | - William E. Klunk
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Chester A. Mathis
- Department of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Milos D. Ikonomovic
- Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA
- Geriatric Research Education and Clinical Center, VA Pittsburgh Clinical System, Pittsburgh, PA
| | - Manik Debnath
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Elizabeth A. Bien
- MassGeneral Institute for NeuroDegenerative Disease, Charlestown, MA
- Department of Neurology, Massachusetts General Hospital, Boston, MA
- Harvard Neurodiscovery Center, Massachusetts General Hospital, Boston, MA
| | - Charles R. Vanderburg
- MassGeneral Institute for NeuroDegenerative Disease, Charlestown, MA
- Department of Neurology, Massachusetts General Hospital, Boston, MA
- Harvard Neurodiscovery Center, Massachusetts General Hospital, Boston, MA
| | - Isabel Costantino
- MassGeneral Institute for NeuroDegenerative Disease, Charlestown, MA
| | - Sara Makaretz
- Department of Neurology, Massachusetts General Hospital, Boston, MA
| | - Sarah L. DeVos
- MassGeneral Institute for NeuroDegenerative Disease, Charlestown, MA
- Department of Neurology, Massachusetts General Hospital, Boston, MA
| | - Derek H. Oakley
- MassGeneral Institute for NeuroDegenerative Disease, Charlestown, MA
- C.S. Kubik Neuropathology Center, Massachusetts General Hospital, Boston, MA
| | - Stephen N. Gomperts
- MassGeneral Institute for NeuroDegenerative Disease, Charlestown, MA
- Department of Neurology, Massachusetts General Hospital, Boston, MA
| | - John H. Growdon
- Department of Neurology, Massachusetts General Hospital, Boston, MA
| | | | - Diane Lucente
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA
| | | | - Matthew P. Frosch
- MassGeneral Institute for NeuroDegenerative Disease, Charlestown, MA
- C.S. Kubik Neuropathology Center, Massachusetts General Hospital, Boston, MA
| | - Bradley T. Hyman
- MassGeneral Institute for NeuroDegenerative Disease, Charlestown, MA
- Department of Neurology, Massachusetts General Hospital, Boston, MA
| | - Keith A. Johnson
- Department of Neurology, Massachusetts General Hospital, Boston, MA
| | - Teresa Gómez-Isla
- MassGeneral Institute for NeuroDegenerative Disease, Charlestown, MA
- Department of Neurology, Massachusetts General Hospital, Boston, MA
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Colmenares-Aguilar MG, Urbina M, Obregón F, Fazzino F, Lima L. Fluoxetine Treatment in Rats Increases the Rate of Taurine Transport in Mononuclear Cells. Neuroimmunomodulation 2017; 24:132-142. [PMID: 29131097 DOI: 10.1159/000480733] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 08/28/2017] [Indexed: 11/19/2022] Open
Abstract
UNLABELLED Fluoxetine, a selective serotonin reuptake inhibitor antidepressant, modulates the mitogen-induced proliferation of lymphocytes. Lymphocytes contain taurine and express taurine transporter (TauT). Among the effects of taurine on lymphocytes are protection against oxidants and regulation of the inflammatory aspects of the immune response. Our aim was to determine the influence of fluoxetine treatment on taurine transport, and to determine the presence of TauT in the mononuclear cells of rats. METHODS Male adult Sprague-Dawley rats were treated with fluoxetine 10 mg/kg i.p. for 1, 2, and 3 weeks. The cells were obtained by density gradients. [3H]Taurine was used for transport assays. Amino acid levels were determined by high-performance liquid chromatography. Immunolabeling of CD4+, CD8+, and TauT was performed. The mRNA of TauT was evaluated by RT-PCR. Controls were included for each protocol. RESULTS The transport of taurine, after 1 week of treatment, was significantly augmented compared to controls. The affinity significantly increased at 1 and 2 weeks. While the percentage of CD4+ cells decreased and that of CD8+ cells increased, the percentage of TauT in CD4+ and CD8+ cells was not affected. Reduction of levels of aspartic acid, glutamic acid, threonine, alanine, glycine, and arginine occurred at 1 and 2 weeks. The taurine concentration significantly decreased after 2 and 3 weeks of treatment. The estimation of mRNA of TauT was not different. CONCLUSION Taurine transport increases with fluoxetine treatment, and so this could be related to an immunomodulatory role of fluoxetine through TauT. Inhibition of serotonin reuptake might be involved in the regulation of taurine transport in mononuclear cells.
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Affiliation(s)
- María Gabriela Colmenares-Aguilar
- Laboratorio de Neuroquímica, Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas, Caracas, Venezuela
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25
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Pinheiro BS, Lemos C, Neutzling Kaufmann F, Marques JM, da Silva-Santos CS, Carvalho E, Mackie K, Rodrigues RJ, Cunha RA, Köfalvi A. Hierarchical glucocorticoid-endocannabinoid interplay regulates the activation of the nucleus accumbens by insulin. Brain Res Bull 2016; 124:222-30. [PMID: 27208730 DOI: 10.1016/j.brainresbull.2016.05.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 05/16/2016] [Accepted: 05/17/2016] [Indexed: 12/28/2022]
Abstract
Here we asked if insulin activation of the nucleus accumbens in vitro is reflected by an increase in (3)H-deoxyglucose ([(3)H]DG) uptake, thus subserving a new model to study molecular mechanisms of central insulin actions. Additionally, we investigated the dependence of this insulin effect on endocannabinoids and corticosteroids, two major culprits in insulin resistance. We found that in acute accumbal slices, insulin (3 and 300nM but not at 0.3nM) produced an increase in [(3)H]DG uptake. The synthetic cannabinoid agonist, WIN55212-2 (500nM) and the glucocorticoid dexamethasone (10μM), impaired insulin (300nM) action on [(3)H]DG uptake. The glucocorticoid receptor (GcR) antagonist, mifepristone (10μM) prevented dexamethasone from inhibiting insulin's action. Strikingly, this anti-insulin action of dexamethasone was also blocked by two CB1 cannabinoid receptor (CB1R) antagonists, O-2050 (500nM) and SR141716A (500nM), as well as by tetrahydrolipstatin (10μM), an inhibitor of diacylglycerol lipases-the enzymes responsible for the synthesis of the endocannabinoid, 2-arachidonoyl-glycerol (2-AG). On the other hand, the blockade of the post-synaptic 2-AG metabolizing enzymes, α,β-serine hydrolase domain 6/12 by WWL70 (1μM) also prevented the action of insulin, probably via increasing endogenous 2-AG tone. Additionally, an anti-insulin receptor (InsR) antibody immunoprecipitated CB1Rs from accumbal homogenates, indicating a physical complexing of CB1Rs with InsRs that supports their functional interaction. Altogether, insulin stimulates glucose uptake in the nucleus accumbens. Accumbal GcR activation triggers the synthesis of 2-AG that in turn binds to the known CB1R-InsR heteromer, thus impeding insulin signaling.
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Affiliation(s)
- Bárbara S Pinheiro
- CNC, Center for Neuroscience and Cell Biology of Coimbra, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Cristina Lemos
- CNC, Center for Neuroscience and Cell Biology of Coimbra, University of Coimbra, 3004-504 Coimbra, Portugal
| | | | - Joana M Marques
- CNC, Center for Neuroscience and Cell Biology of Coimbra, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Carla S da Silva-Santos
- CNC, Center for Neuroscience and Cell Biology of Coimbra, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Eugénia Carvalho
- CNC, Center for Neuroscience and Cell Biology of Coimbra, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Ken Mackie
- Department of Psychological and Brain Sciences, Gill Center for Biomolecular Science, Indiana University, Bloomington, IN, USA
| | - Ricardo J Rodrigues
- CNC, Center for Neuroscience and Cell Biology of Coimbra, University of Coimbra, 3004-504 Coimbra, Portugal; Institute for Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal
| | - Rodrigo A Cunha
- CNC, Center for Neuroscience and Cell Biology of Coimbra, University of Coimbra, 3004-504 Coimbra, Portugal; FMUC, Faculty of Medicine, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Attila Köfalvi
- CNC, Center for Neuroscience and Cell Biology of Coimbra, University of Coimbra, 3004-504 Coimbra, Portugal; Institute for Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal.
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Nakano T, Inoue I, Takenaka Y, Ono H, Katayama S, Awata T, Murakoshi T. Ezetimibe Promotes Brush Border Membrane-to-Lumen Cholesterol Efflux in the Small Intestine. PLoS One 2016; 11:e0152207. [PMID: 27023132 PMCID: PMC4811413 DOI: 10.1371/journal.pone.0152207] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 03/10/2016] [Indexed: 11/19/2022] Open
Abstract
Ezetimibe inhibits Niemann-Pick C1-like 1 (NPC1L1), an apical membrane cholesterol transporter of enterocytes, thereby reduces intestinal cholesterol absorption. This treatment also increases extrahepatic reverse cholesterol transport via an undefined mechanism. To explore this, we employed a trans-intestinal cholesterol efflux (TICE) assay, which directly detects circulation-to-intestinal lumen 3H-cholesterol transit in a cannulated jejunal segment, and found an increase of TICE by 45%. To examine whether such increase in efflux occurs at the intestinal brush border membrane(BBM)-level, we performed luminal perfusion assays, similar to TICE but the jejunal wall was labelled with orally-given 3H-cholesterol, and determined elevated BBM-to-lumen cholesterol efflux by 3.5-fold with ezetimibe. Such increased efflux probably promotes circulation-to-lumen cholesterol transit eventually; thus increases TICE. Next, we wondered how inhibition of NPC1L1, an influx transporter, resulted in increased efflux. When we traced orally-given 3H-cholesterol in mice, we found that lumen-to-BBM 3H-cholesterol transit was rapid and less sensitive to ezetimibe treatment. Comparison of the efflux and fractional cholesterol absorption revealed an inverse correlation, indicating the efflux as an opposite-regulatory factor for cholesterol absorption efficiency and counteracting to the naturally-occurring rapid cholesterol influx to the BBM. These suggest that the ezetimibe-stimulated increased efflux is crucial in reducing cholesterol absorption. Ezetimibe-induced increase in cholesterol efflux was approximately 2.5-fold greater in mice having endogenous ATP-binding cassette G5/G8 heterodimer, the major sterol efflux transporter of enterocytes, than the knockout counterparts, suggesting that the heterodimer confers additional rapid BBM-to-lumen cholesterol efflux in response to NPC1L1 inhibition. The observed framework for intestinal cholesterol fluxes may provide ways to modulate the flux to dispose of endogenous cholesterol efficiently for therapeutic purposes.
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Affiliation(s)
- Takanari Nakano
- Department of Biochemistry, Faculty of Medicine, Saitama Medical University, Iruma-gun, Saitama, Japan
- * E-mail:
| | - Ikuo Inoue
- Department of Diabetes and Endocrinology, Faculty of Medicine, Saitama Medical University, Iruma-gun, Saitama, Japan
| | - Yasuhiro Takenaka
- Department of Diabetes and Endocrinology, Faculty of Medicine, Saitama Medical University, Iruma-gun, Saitama, Japan
| | - Hiraku Ono
- Department of Diabetes and Endocrinology, Faculty of Medicine, Saitama Medical University, Iruma-gun, Saitama, Japan
| | - Shigehiro Katayama
- Department of Diabetes and Endocrinology, Faculty of Medicine, Saitama Medical University, Iruma-gun, Saitama, Japan
| | - Takuya Awata
- Department of Diabetes, Endocrinology and Metabolism, International University of Health and Welfare Hospital, Nasushiobara-shi, Tochigi, Japan
| | - Takayuki Murakoshi
- Department of Biochemistry, Faculty of Medicine, Saitama Medical University, Iruma-gun, Saitama, Japan
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27
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Mihok S, Wilk M, Lapp A, St-Amant N, Kwamena NOA, Clark ID. Tritium dynamics in soils and plants grown under three irrigation regimes at a tritium processing facility in Canada. J Environ Radioact 2016; 153:176-187. [PMID: 26773512 DOI: 10.1016/j.jenvrad.2015.12.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Revised: 12/27/2015] [Accepted: 12/28/2015] [Indexed: 06/05/2023]
Abstract
The dynamics of tritium released from nuclear facilities as tritiated water (HTO) have been studied extensively with results incorporated into regulatory assessment models. These models typically estimate organically bound tritium (OBT) for calculating public dose as OBT itself is rarely measured. Higher than expected OBT/HTO ratios in plants and soils are an emerging issue that is not well understood. To support the improvement of models, an experimental garden was set up in 2012 at a tritium processing facility in Pembroke, Ontario to characterize the circumstances under which high OBT/HTO ratios may arise. Soils and plants were sampled weekly to coincide with detailed air and stack monitoring. The design included a plot of native grass/soil, contrasted with sod and vegetables grown in barrels with commercial topsoil under natural rain and either low or high tritium irrigation water. Air monitoring indicated that the plume was present infrequently at concentrations of up to about 100 Bq/m(3) (the garden was not in a major wind sector). Mean air concentrations during the day on workdays (HTO 10.3 Bq/m(3), HT 5.8 Bq/m(3)) were higher than at other times (0.7-2.6 Bq/m(3)). Mean Tissue Free Water Tritium (TFWT) in plants and soils and OBT/HTO ratios were only very weakly or not at all correlated with releases on a weekly basis. TFWT was equal in soils and plants and in above and below ground parts of vegetables. OBT/HTO ratios in above ground parts of vegetables were above one when the main source of tritium was from high tritium irrigation water (1.5-1.8). Ratios were below one in below ground parts of vegetables when irrigated with high tritium water (0.4-0.6) and above one in vegetables rain-fed or irrigated with low tritium water (1.3-2.8). In contrast, OBT/HTO ratios were very high (9.0-13.5) when the source of tritium was mainly from the atmosphere. TFWT varied considerably through time as a result of SRBT's operations; OBT/HTO ratios showed no clear temporal pattern in above or below ground plant parts. Native soil after ∼20 years of operations at SRBT had high initial OBT that persisted through the growing season; little OBT formed in garden plot soil during experiments. High OBT in native soil appeared to be a signature of higher past releases at SRBT. This phenomenon was confirmed in soils obtained at another processing facility in Canada with a similar history. The insights into variation in OBT/HTO ratios found here are of regulatory interest and should be incorporated in assessment models to aid in the design of relevant environmental monitoring programs for OBT.
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Affiliation(s)
- S Mihok
- Canadian Nuclear Safety Commission, 280 Slater Street, P.O. Box 1046, Station B, Ottawa, Ontario K1P 5S9, Canada.
| | - M Wilk
- Department of Earth Sciences, 140 Louis-Pasteur, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - A Lapp
- Department of Earth Sciences, 140 Louis-Pasteur, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - N St-Amant
- Canadian Nuclear Safety Commission, 280 Slater Street, P.O. Box 1046, Station B, Ottawa, Ontario K1P 5S9, Canada
| | - N-O A Kwamena
- Canadian Nuclear Safety Commission, 280 Slater Street, P.O. Box 1046, Station B, Ottawa, Ontario K1P 5S9, Canada
| | - I D Clark
- Department of Earth Sciences, 140 Louis-Pasteur, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
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Erdozain AM, Rubio M, Meana JJ, Fernández-Ruiz J, Callado LF. Altered CB1 receptor coupling to G-proteins in the post-mortem caudate nucleus and cerebellum of alcoholic subjects. J Psychopharmacol 2015; 29:1137-45. [PMID: 26253623 DOI: 10.1177/0269881115599388] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Biochemical, pharmacological and genetic evidence suggests the involvement of the endocannabinoid system in alcohol dependence. The aim of the present study was to evaluate the state of CB1 receptors in post-mortem caudate nucleus, hippocampus and cerebellum of alcoholic subjects.CB1 protein levels were measured by Western blot, CB1 receptor density and affinity by [(3)H]WIN55,212-2 saturation assays and CB1 functionality by [(35)S]GTPγS binding assays. Experiments were performed in samples from 24 subjects classified as non-suicidal alcoholics (n = 6), suicidal alcoholics (n = 6), non-alcoholic suicide victims (n = 6) and control subjects (n = 6).Alcoholic subjects presented hyperfunctional CB1 receptors in the caudate nucleus resulting in a higher maximal effect in both alcoholic groups compared to the non-alcoholic groups (p < 0.001). Conversely, in the cerebellum the non-suicidal alcoholic subjects showed hypofunctional receptors with lower maximal effect and potency (p < 0.001). No changes were found in the CB1 protein expression in either region. In the hippocampus of alcoholic subjects, no changes were observed either in the functionality, density or protein levels.Our data support an association between endocannabinoid system activity and alcoholism. The modifications reported here could be either a consequence of high lifetime ethanol consumption or a vulnerability factor to develop alcohol addiction.
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Affiliation(s)
- Amaia M Erdozain
- Department of Pharmacology, University of the Basque Country UPV/EHU, Bizkaia, Spain Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain Current address: Neuroscience Paris Seine, CNRS UMR 8246, INSERM U1130, Université Pierre et Marie Curie, Paris, France
| | - Marina Rubio
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, Complutense University, Madrid, Spain
| | - J Javier Meana
- Department of Pharmacology, University of the Basque Country UPV/EHU, Bizkaia, Spain Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain Biocruces Health Research Institute, Bizkaia, Spain
| | - Javier Fernández-Ruiz
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, Complutense University, Madrid, Spain Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain Instituto Ramón y Cajal de Investigaciones Sanitarias (IRYCIS), Madrid, Spain
| | - Luis F Callado
- Department of Pharmacology, University of the Basque Country UPV/EHU, Bizkaia, Spain Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain Biocruces Health Research Institute, Bizkaia, Spain
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29
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Connan O, Maro D, Hébert D, Solier L, Caldeira Ideas P, Laguionie P, St-Amant N. In situ measurements of tritium evapotranspiration (³H-ET) flux over grass and soil using the gradient and eddy covariance experimental methods and the FAO-56 model. J Environ Radioact 2015; 148:1-9. [PMID: 26091609 DOI: 10.1016/j.jenvrad.2015.06.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 06/01/2015] [Accepted: 06/06/2015] [Indexed: 06/04/2023]
Abstract
The behaviour of tritium in the environment is linked to the water cycle. We compare three methods of calculating the tritium evapotranspiration flux from grassland cover. The gradient and eddy covariance methods, together with a method based on the theoretical Penmann-Monteith model were tested in a study carried out in 2013 in an environment characterised by high levels of tritium activity. The results show that each of the three methods gave similar results. The various constraints applying to each method are discussed. The results show a tritium evapotranspiration flux of around 15 mBq m(-2) s(-1) in this environment. These results will be used to improve the entry parameters for the general models of tritium transfers in the environment.
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Affiliation(s)
- O Connan
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LRC, Laboratoire de Radioécologie de Cherbourg Octeville, Cherbourg-Octeville 50130, France.
| | - D Maro
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LRC, Laboratoire de Radioécologie de Cherbourg Octeville, Cherbourg-Octeville 50130, France
| | - D Hébert
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LRC, Laboratoire de Radioécologie de Cherbourg Octeville, Cherbourg-Octeville 50130, France
| | - L Solier
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LRC, Laboratoire de Radioécologie de Cherbourg Octeville, Cherbourg-Octeville 50130, France
| | - P Caldeira Ideas
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), IPRP-ENV/SESURE/LS3E, Laboratoire de Surveillance et d'Expertise Environnementale par Echantillonnage, Le Vésinet 78116, France
| | - P Laguionie
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LRC, Laboratoire de Radioécologie de Cherbourg Octeville, Cherbourg-Octeville 50130, France
| | - N St-Amant
- Canadian Nuclear Safety Commission, Ottawa, Canada
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30
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Nie B, Ni M, Jiang J, Wu Y. Dynamic evaluation of environmental impact due to tritium accidental release from the fusion reactor. J Environ Radioact 2015; 148:137-140. [PMID: 26164282 DOI: 10.1016/j.jenvrad.2015.06.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 06/16/2015] [Accepted: 06/18/2015] [Indexed: 06/04/2023]
Abstract
As one of the key safety issues of fusion reactors, tritium environmental impact of fusion accidents has attracted great attention. In this work, the dynamic tritium concentrations in the air and human body were evaluated on the time scale based on accidental release scenarios under the extreme environmental conditions. The radiation dose through various exposure pathways was assessed to find out the potential relationships among them. Based on this work, the limits of HT and HTO release amount for arbitrary accidents were proposed for the fusion reactor according to dose limit of ITER. The dynamic results aim to give practical guidance for establishment of fusion emergency standard and design of fusion tritium system.
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Affiliation(s)
- Baojie Nie
- Key Laboratory of Neutronics and Radiation Safety, Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences, Hefei, Anhui 230031, China; University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Muyi Ni
- Key Laboratory of Neutronics and Radiation Safety, Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences, Hefei, Anhui 230031, China.
| | - Jieqiong Jiang
- Key Laboratory of Neutronics and Radiation Safety, Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Yican Wu
- Key Laboratory of Neutronics and Radiation Safety, Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences, Hefei, Anhui 230031, China; University of Science and Technology of China, Hefei, Anhui 230027, China
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Xiao Z, Guo W, Yuen SMWK, Wang R, Zhang L, Van Petegem F, Chen SRW. The H29D Mutation Does Not Enhance Cytosolic Ca2+ Activation of the Cardiac Ryanodine Receptor. PLoS One 2015; 10:e0139058. [PMID: 26405799 PMCID: PMC4583508 DOI: 10.1371/journal.pone.0139058] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 09/07/2015] [Indexed: 11/25/2022] Open
Abstract
The N-terminal domain of the cardiac ryanodine receptor (RyR2) harbors a large number of naturally occurring mutations that are associated with stress-induced ventricular tachyarrhythmia and sudden death. Nearly all these disease-associated N-terminal mutations are located at domain interfaces or buried within domains. Mutations at these locations would alter domain-domain interactions or the stability/folding of domains. Recently, a novel RyR2 mutation H29D associated with ventricular arrhythmia at rest was found to enhance the activation of single RyR2 channels by diastolic levels of cytosolic Ca2+. Unlike other N-terminal disease-associated mutations, the H29D mutation is located on the surface of the N-terminal domain. It is unclear how this surface-exposed H29D mutation that does not appear to interact with other parts of the RyR2 structure could alter the intrinsic properties of the channel. Here we carried out detailed functional characterization of the RyR2-H29D mutant at the molecular and cellular levels. We found that the H29D mutation has no effect on the basal level or the Ca2+ dependent activation of [3H]ryanodine binding to RyR2, the cytosolic Ca2+ activation of single RyR2 channels, or the cytosolic Ca2+- or caffeine-induced Ca2+ release in HEK293 cells. In addition, the H29D mutation does not alter the propensity for spontaneous Ca2+ release or the thresholds for Ca2+ release activation or termination. Furthermore, the H29D mutation does not have significant impact on the thermal stability of the N-terminal region (residues 1–547) of RyR2. Collectively, our data show that the H29D mutation exerts little or no effect on the function of RyR2 or on the folding stability of the N-terminal region. Thus, our results provide no evidence that the H29D mutation enhances the cytosolic Ca2+ activation of RyR2.
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Affiliation(s)
- Zhichao Xiao
- Libin Cardiovascular Institute of Alberta, Department of Physiology & Pharmacology, University of Calgary, Calgary, Alberta, Canada T2N 4N1
- Libin Cardiovascular Institute of Alberta, Department of Biochemistry & Molecular Biology, University of Calgary, Calgary, Alberta, Canada T2N 4N1
| | - Wenting Guo
- Libin Cardiovascular Institute of Alberta, Department of Physiology & Pharmacology, University of Calgary, Calgary, Alberta, Canada T2N 4N1
- Libin Cardiovascular Institute of Alberta, Department of Biochemistry & Molecular Biology, University of Calgary, Calgary, Alberta, Canada T2N 4N1
| | - Siobhan M. Wong King Yuen
- Department of Biochemistry and Molecular Biology, University of British Columbia, 2350 Health Sciences Mall, Vancouver, Canada V6T 1Z3
| | - Ruiwu Wang
- Libin Cardiovascular Institute of Alberta, Department of Physiology & Pharmacology, University of Calgary, Calgary, Alberta, Canada T2N 4N1
- Libin Cardiovascular Institute of Alberta, Department of Biochemistry & Molecular Biology, University of Calgary, Calgary, Alberta, Canada T2N 4N1
| | - Lin Zhang
- Libin Cardiovascular Institute of Alberta, Department of Physiology & Pharmacology, University of Calgary, Calgary, Alberta, Canada T2N 4N1
- Libin Cardiovascular Institute of Alberta, Department of Biochemistry & Molecular Biology, University of Calgary, Calgary, Alberta, Canada T2N 4N1
| | - Filip Van Petegem
- Department of Biochemistry and Molecular Biology, University of British Columbia, 2350 Health Sciences Mall, Vancouver, Canada V6T 1Z3
| | - S. R. Wayne Chen
- Libin Cardiovascular Institute of Alberta, Department of Physiology & Pharmacology, University of Calgary, Calgary, Alberta, Canada T2N 4N1
- Libin Cardiovascular Institute of Alberta, Department of Biochemistry & Molecular Biology, University of Calgary, Calgary, Alberta, Canada T2N 4N1
- * E-mail:
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Brewer PB, Dun EA, Gui R, Mason MG, Beveridge CA. Strigolactone Inhibition of Branching Independent of Polar Auxin Transport. Plant Physiol 2015; 168:1820-9. [PMID: 26111543 PMCID: PMC4528729 DOI: 10.1104/pp.15.00014] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 06/24/2015] [Indexed: 05/20/2023]
Abstract
The outgrowth of axillary buds into branches is regulated systemically via plant hormones and the demand of growing shoot tips for sugars. The plant hormone auxin is thought to act via two mechanisms. One mechanism involves auxin regulation of systemic signals, cytokinins and strigolactones, which can move into axillary buds. The other involves suppression of auxin transport/canalization from axillary buds into the main stem and is enhanced by a low sink for auxin in the stem. In this theory, the relative ability of the buds and stem to transport auxin controls bud outgrowth. Here, we evaluate whether auxin transport is required or regulated during bud outgrowth in pea (Pisum sativum). The profound, systemic, and long-term effects of the auxin transport inhibitor N-1-naphthylphthalamic acid had very little inhibitory effect on bud outgrowth in strigolactone-deficient mutants. Strigolactones can also inhibit bud outgrowth in N-1-naphthylphthalamic acid-treated shoots that have greatly diminished auxin transport. Moreover, strigolactones can inhibit bud outgrowth despite a much diminished auxin supply in in vitro or decapitated plants. These findings demonstrate that auxin sink strength in the stem is not important for bud outgrowth in pea. Consistent with alternative mechanisms of auxin regulation of systemic signals, enhanced auxin biosynthesis in Arabidopsis (Arabidopsis thaliana) can suppress branching in yucca1D plants compared with wild-type plants, but has no effect on bud outgrowth in a strigolactone-deficient mutant background.
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Affiliation(s)
- Philip B Brewer
- The University of Queensland, School of Biological Sciences, St. Lucia, Queensland 4072, Australia
| | - Elizabeth A Dun
- The University of Queensland, School of Biological Sciences, St. Lucia, Queensland 4072, Australia
| | - Renyi Gui
- The University of Queensland, School of Biological Sciences, St. Lucia, Queensland 4072, Australia
| | - Michael G Mason
- The University of Queensland, School of Biological Sciences, St. Lucia, Queensland 4072, Australia
| | - Christine A Beveridge
- The University of Queensland, School of Biological Sciences, St. Lucia, Queensland 4072, Australia
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Reddig A, Fatahi M, Friebe B, Guttek K, Hartig R, Godenschweger F, Roggenbuck D, Ricke J, Reinhold D, Speck O. Analysis of DNA Double-Strand Breaks and Cytotoxicity after 7 Tesla Magnetic Resonance Imaging of Isolated Human Lymphocytes. PLoS One 2015; 10:e0132702. [PMID: 26176601 PMCID: PMC4503586 DOI: 10.1371/journal.pone.0132702] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Accepted: 06/17/2015] [Indexed: 01/25/2023] Open
Abstract
The global use of magnetic resonance imaging (MRI) is constantly growing and the field strengths increasing. Yet, only little data about harmful biological effects caused by MRI exposure are available and published research analyzing the impact of MRI on DNA integrity reported controversial results. This in vitro study aimed to investigate the genotoxic and cytotoxic potential of 7 T ultra-high-field MRI on isolated human peripheral blood mononuclear cells. Hence, unstimulated mononuclear blood cells were exposed to 7 T static magnetic field alone or in combination with maximum permissible imaging gradients and radiofrequency pulses as well as to ionizing radiation during computed tomography and γ-ray exposure. DNA double-strand breaks were quantified by flow cytometry and automated microscopy analysis of immunofluorescence stained γH2AX. Cytotoxicity was studied by CellTiter-Blue viability assay and [3H]-thymidine proliferation assay. Exposure of unstimulated mononuclear blood cells to 7 T static magnetic field alone or combined with varying gradient magnetic fields and pulsed radiofrequency fields did not induce DNA double-strand breaks, whereas irradiation with X- and γ-rays led to a dose-dependent induction of γH2AX foci. The viability assay revealed a time- and dose-dependent decrease in metabolic activity only among samples exposed to γ-radiation. Further, there was no evidence for altered proliferation response after cells were exposed to 7 T MRI or low doses of ionizing radiation (≤ 0.2 Gy). These findings confirm the acceptance of MRI as a safe non-invasive diagnostic imaging tool, but whether MRI can induce other types of DNA lesions or DNA double-strand breaks during altered conditions still needs to be investigated.
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Affiliation(s)
- Annika Reddig
- Institute of Molecular and Clinical Immunology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany
- * E-mail:
| | - Mahsa Fatahi
- Department of Biomedical Magnetic Resonance, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany
| | - Björn Friebe
- Department of Radiology and Nuclear Medicine, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany
| | - Karina Guttek
- Institute of Molecular and Clinical Immunology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany
| | - Roland Hartig
- Institute of Molecular and Clinical Immunology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany
| | - Frank Godenschweger
- Department of Biomedical Magnetic Resonance, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany
| | - Dirk Roggenbuck
- Medipan GmbH, Dahlewitz/Berlin, Germany
- Faculty of Natural Sciences, Brandenburg University of Technology Cottbus-Senftenberg, Senftenberg, Germany
| | - Jens Ricke
- Department of Radiology and Nuclear Medicine, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany
| | - Dirk Reinhold
- Institute of Molecular and Clinical Immunology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany
| | - Oliver Speck
- Department of Biomedical Magnetic Resonance, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany
- Leibniz Institute for Neurobiology, Magdeburg, Germany
- Center for Behavioral Brain Sciences, Magdeburg, Germany
- German Center for Neurodegenerative Disease, Magdeburg, Germany
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Schwarz LK, Villegas-Amtmann S, Beltran RS, Costa DP, Goetsch C, Hückstädt L, Maresh JL, Peterson SH. Comparisons and Uncertainty in Fat and Adipose Tissue Estimation Techniques: The Northern Elephant Seal as a Case Study. PLoS One 2015; 10:e0131877. [PMID: 26121044 PMCID: PMC4486730 DOI: 10.1371/journal.pone.0131877] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 06/08/2015] [Indexed: 11/18/2022] Open
Abstract
Fat mass and body condition are important metrics in bioenergetics and physiological studies. They can also link foraging success with demographic rates, making them key components of models that predict population-level outcomes of environmental change. Therefore, it is important to incorporate uncertainty in physiological indicators if results will lead to species management decisions. Maternal fat mass in elephant seals (Mirounga spp) can predict reproductive rate and pup survival, but no one has quantified or identified the sources of uncertainty for the two fat mass estimation techniques (labeled-water and truncated cones). The current cones method can provide estimates of proportion adipose tissue in adult females and proportion fat of juveniles in northern elephant seals (M. angustirostris) comparable to labeled-water methods, but it does not work for all cases or species. We reviewed components and assumptions of the technique via measurements of seven early-molt and seven late-molt adult females. We show that seals are elliptical on land, rather than the assumed circular shape, and skin may account for a high proportion of what is often defined as blubber. Also, blubber extends past the neck-to-pelvis region, and comparisons of new and old ultrasound instrumentation indicate previous measurements of sculp thickness may be biased low. Accounting for such differences, and incorporating new measurements of blubber density and proportion of fat in blubber, we propose a modified cones method that can isolate blubber from non-blubber adipose tissue and separate fat into skin, blubber, and core compartments. Lastly, we found that adipose tissue and fat estimates using tritiated water may be biased high during the early molt. Both the tritiated water and modified cones methods had high, but reducible, uncertainty. The improved cones method for estimating body condition allows for more accurate quantification of the various tissue masses and may also be transferrable to other species.
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Affiliation(s)
- Lisa K. Schwarz
- Institute of Marine Sciences, University of California Santa Cruz, Santa Cruz, California, United States of America
- * E-mail:
| | - Stella Villegas-Amtmann
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Roxanne S. Beltran
- Department of Biological Sciences, University of Alaska, Anchorage, Alaska, United States of America
| | - Daniel P. Costa
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Chandra Goetsch
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Luis Hückstädt
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Jennifer L. Maresh
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Sarah H. Peterson
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
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Deng Q, Waxse B, Riquelme D, Zhang J, Aguilera G. Helix 8 of the ligand binding domain of the glucocorticoid receptor (GR) is essential for ligand binding. Mol Cell Endocrinol 2015; 408:23-32. [PMID: 25676569 PMCID: PMC4417367 DOI: 10.1016/j.mce.2015.01.044] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 01/16/2015] [Accepted: 01/30/2015] [Indexed: 12/20/2022]
Abstract
Membrane association of estrogen receptors (ER) depends on cysteine palmitoylation and two leucines in the ligand binding domain (LBD), conserved in most steroid receptors. The role of this region, corresponding to helix 8 of the glucocorticoid receptor (GR) LBD, on membrane association of GR was studied in 4B cells, expressing endogenous GR, and Cos-7 cells transfected EGFP-GR constructs. 4B cells preloaded with radiolabeled palmitic acid showed no radioactivity incorporation into immunoprecipitated GR. Moreover, mutation C683A (corresponding to ER palmitoylation site) did not affect corticosterone-induced membrane association of GR. Mutations L687-690A, L682A, E680G and K685G prevented membrane and also nuclear localization through reduced ligand binding. L687-690A mutation decreased association of GR with heat shock protein 90 and transcriptional activity, without overt effects on receptor protein stability. The data demonstrate that palmitoylation does not mediate membrane association of GR, but that the region 680-690 (helix 8) is critical for ligand binding and receptor function.
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Affiliation(s)
- Qiong Deng
- Section on Endocrine Physiology, PDEGEN, NICHD, NIH, Bethesda, Maryland, USA; College of Animal Sciences, Jilin University, China
| | - Bennett Waxse
- Section on Organelle Biology, CBMP, NICHD, NIH, Bethesda, Maryland, USA
| | - Denise Riquelme
- Section on Endocrine Physiology, PDEGEN, NICHD, NIH, Bethesda, Maryland, USA
| | - Jiabao Zhang
- College of Animal Sciences, Jilin University, China
| | - Greti Aguilera
- Section on Endocrine Physiology, PDEGEN, NICHD, NIH, Bethesda, Maryland, USA.
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García-Cabezas MÁ, Barbas H. A direct anterior cingulate pathway to the primate primary olfactory cortex may control attention to olfaction. Brain Struct Funct 2015; 219:1735-54. [PMID: 23797208 DOI: 10.1007/s00429-013-0598-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Accepted: 06/05/2013] [Indexed: 11/25/2022]
Abstract
Behavioral and functional studies in humans suggest that attention plays a key role in activating the primary olfactory cortex through an unknown circuit mechanism. We report that a novel pathway from the anterior cingulate cortex, an area which has a key role in attention, projects directly to the primary olfactory cortex in rhesus monkeys, innervating mostly the anterior olfactory nucleus. Axons from the anterior cingulate cortex formed synapses mostly with spines of putative excitatory pyramidal neurons and with a small proportion of a neurochemical class of inhibitory neurons that are thought to have disinhibitory effect on excitatory neurons. This novel pathway from the anterior cingulate is poised to exert a powerful excitatory effect on the anterior olfactory nucleus, which is a critical hub for odorant processing via extensive bilateral connections with primary olfactory cortices and the olfactory bulb. Acting on the anterior olfactory nucleus, the anterior cingulate may activate the entire primary olfactory cortex to mediate the process of rapid attention to olfactory stimuli.
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Kudryasheva NS, Rozhko TV. Effect of low-dose ionizing radiation on luminous marine bacteria: radiation hormesis and toxicity. J Environ Radioact 2015; 142:68-77. [PMID: 25644753 DOI: 10.1016/j.jenvrad.2015.01.012] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 01/12/2015] [Accepted: 01/12/2015] [Indexed: 06/04/2023]
Abstract
The paper summarizes studies of effects of alpha- and beta-emitting radionuclides (americium-241, uranium-235+238, and tritium) on marine microorganisms under conditions of chronic low-dose irradiation in aqueous media. Luminous marine bacteria were chosen as an example of these microorganisms; bioluminescent intensity was used as a tested physiological parameter. Non-linear dose-effect dependence was demonstrated. Three successive stages in the bioluminescent response to americium-241 and tritium were found: 1--absence of effects (stress recognition), 2--activation (adaptive response), and 3--inhibition (suppression of physiological function, i.e. radiation toxicity). The effects were attributed to radiation hormesis phenomenon. Biological role of reactive oxygen species, secondary products of the radioactive decay, is discussed. The study suggests an approach to evaluation of non-toxic and toxic stages under conditions of chronic radioactive exposure.
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Affiliation(s)
- N S Kudryasheva
- Institute of Biophysics SB RAS, Akademgorodok 50, 660036, Krasnoyarsk, Russia; Siberian Federal University, Svobodny 79, 660041, Krasnoyarsk, Russia.
| | - T V Rozhko
- Siberian Federal University, Svobodny 79, 660041, Krasnoyarsk, Russia; Krasnoyarsk State Medical Academy, P. Zheleznyaka 1, 660022, Krasnoyarsk, Russia
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38
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Franková L, Fry SC. A general method for assaying homo- and hetero-transglycanase activities that act on plant cell-wall polysaccharides. J Integr Plant Biol 2015; 57:411-428. [PMID: 25641334 DOI: 10.1111/jipb.12337] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 01/26/2015] [Indexed: 06/04/2023]
Abstract
Transglycanases (endotransglycosylases) cleave a polysaccharide (donor-substrate) in mid-chain, and then transfer a portion onto another poly- or oligosaccharide (acceptor-substrate). Such enzymes contribute to plant cell-wall assembly and/or re-structuring. We sought a general method for revealing novel homo- and hetero-transglycanases, applicable to diverse polysaccharides and oligosaccharides, separating transglycanase-generated (3)H-polysaccharides from unreacted (3)H-oligosaccharides--the former immobilized (on filter-paper, silica-gel or glass-fiber), the latter eluted. On filter-paper, certain polysaccharides [e.g. (1→3, 1→4)-β-D-glucans] remained satisfactorily adsorbed when water-washed; others (e.g. pectins) were partially lost. Many oligosaccharides (e.g. arabinan-, galactan-, xyloglucan-based) were successfully eluted in appropriate solvents, but others (e.g. [(3)H]xylohexaitol, [(3)H]mannohexaitol [(3)H]cellohexaitol) remained immobile. On silica-gel, all (3)H-oligosaccharides left an immobile 'ghost' spot (contaminating any (3)H-polysaccharides), which was diminished but not prevented by additives e.g. sucrose or Triton X-100. The best stratum was glass-fiber (GF), onto which the reaction-mixture was dried then washed in 75% ethanol. Washing led to minimal loss or lateral migration of (3)H-polysaccharides if conducted by slow percolation of acidified ethanol. The effectiveness of GF-blotting was well demonstrated for Chara vulgaris trans-β-mannanase. In conclusion, our novel GF-blotting technique efficiently frees transglycanase-generated (3)H-polysaccharides from unreacted (3)H-oligosaccharides, enabling high-throughput screening of multiple postulated transglycanase activities utilising chemically diverse donor- and acceptor-substrates.
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Affiliation(s)
- Lenka Franková
- The Edinburgh Cell Wall Group, Institute of Molecular Plant Sciences, The University of Edinburgh, Daniel Rutherford Building, The King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
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de Castro M, Miller JG, Acebes JL, Encina A, García-Angulo P, Fry SC. The biosynthesis and wall-binding of hemicelluloses in cellulose-deficient maize cells: an example of metabolic plasticity. J Integr Plant Biol 2015; 57:373-387. [PMID: 25611087 DOI: 10.1111/jipb.12331] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Accepted: 01/19/2015] [Indexed: 06/04/2023]
Abstract
Cell-suspension cultures (Zea mays L., Black Mexican sweet corn) habituated to 2,6-dichlorobenzonitrile (DCB) survive with reduced cellulose owing to hemicellulose network modification. We aimed to define the hemicellulose metabolism modifications in DCB-habituated maize cells showing a mild reduction in cellulose at different stages in the culture cycle. Using pulse-chase radiolabeling, we fed habituated and non-habituated cultures with [(3)H]arabinose, and traced the distribution of (3)H-pentose residues between xylans, xyloglucans and other polymers in several cellular compartments for 5 h. Habituated cells were slower taking up exogenous [(3)H]arabinose. Tritium was incorporated into polysaccharide-bound arabinose and xylose residues, but habituated cells diverted a higher proportion of their new [(3)H]xylose residues into (hetero) xylans at the expense of xyloglucan synthesis. During logarithmic growth, habituated cells showed slower vesicular trafficking of polymers, especially xylans. Moreover, habituated cells showed a decrease in the strong wall-binding of all pentose-containing polysaccharides studied; correspondingly, especially in log-phase cultures, habituation increased the proportion of (3)H-hemicelluloses ([(3)H]xylans and [(3)H]xyloglucan) sloughed into the medium. These findings could be related to the cell walls' cellulose-deficiency, and consequent reduction in binding sites for hemicelluloses; the data could also reflect the habituated cells' reduced capacity to integrate arabinoxylans by extra-protoplasmic phenolic cross-linking, as well as xyloglucans, during wall assembly.
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Affiliation(s)
- María de Castro
- The Edinburgh Cell Wall Group, Institute of Molecular Plant Sciences, School of Biological Sciences, Daniel Rutherford Building, The King's Buildings, Edinburgh, EH9 3JH, UK; Laboratory of Plant Physiology, Faculty of Biological and Environmental Sciences, University of Léon, E-24071, León, Spain
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Sun H, Tao J, Liu S, Huang S, Chen S, Xie X, Yoneyama K, Zhang Y, Xu G. Strigolactones are involved in phosphate- and nitrate-deficiency-induced root development and auxin transport in rice. J Exp Bot 2014; 65:6735-46. [PMID: 24596173 PMCID: PMC4246174 DOI: 10.1093/jxb/eru029] [Citation(s) in RCA: 168] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Strigolactones (SLs) or their derivatives have recently been defined as novel phytohormones that regulate root development. However, it remains unclear whether SLs mediate root growth in response to phosphorus (P) and nitrogen (N) deficiency. In this study, the responses of root development in rice (Oryza sativa L.) to different levels of phosphate and nitrate supply were investigated using wild type (WT) and mutants defective in SL synthesis (d10 and d27) or insensitive to SL (d3). Reduced concentration of either phosphate or nitrate led to increased seminal root length and decreased lateral root density in WT. Limitation of either P or N stimulated SL production and enhanced expression of D10, D17, and D27 and suppressed expression of D3 and D14 in WT roots. Mutation of D10, D27, or D3 caused loss of sensitivity of root response to P and N deficiency. Application of the SL analogue GR24 restored seminal root length and lateral root density in WT and d10 and d27 mutants but not in the d3 mutant, suggesting that SLs were induced by nutrient-limiting conditions and led to changes in rice root growth via D3. Moreover, P or N deficiency or GR24 application reduced the transport of radiolabelled indole-3-acetic acid and the activity of DR5::GUS auxin reporter in WT and d10 and d27 mutants. These findings highlight the role of SLs in regulating rice root development under phosphate and nitrate limitation. The mechanisms underlying this regulatory role involve D3 and modulation of auxin transport from shoots to roots.
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Affiliation(s)
- Huwei Sun
- Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
| | - Jinyuan Tao
- Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
| | - Shangjun Liu
- Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
| | - Shuangjie Huang
- Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
| | - Si Chen
- Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
| | - Xiaonan Xie
- Weed Science Center, Utsunomiya University, 350 Mine-machi, Utsunomiya 321-8505, Japan
| | - Koichi Yoneyama
- Weed Science Center, Utsunomiya University, 350 Mine-machi, Utsunomiya 321-8505, Japan
| | - Yali Zhang
- Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
| | - Guohua Xu
- Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
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Matveev SV, Kwiatkowski S, Sviripa VM, Fazio RC, Watt DS, LeVine H. Tritium-labeled (E,E)-2,5-bis(4'-hydroxy-3'-carboxystyryl)benzene as a probe for β-amyloid fibrils. Bioorg Med Chem Lett 2014; 24:5534-6. [PMID: 25452000 PMCID: PMC4254541 DOI: 10.1016/j.bmcl.2014.09.075] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 09/11/2014] [Accepted: 09/24/2014] [Indexed: 12/20/2022]
Abstract
Accumulation of Aβ in the brains of Alzheimer disease (AD) patients reflects an imbalance between Aβ production and clearance from their brains. Alternative cleavage of amyloid precursor protein (APP) by processing proteases generates soluble APP fragments including the neurotoxic amyloid Aβ40 and Aβ42 peptides that assemble into fibrils and form plaques. Plaque-buildup occurs over an extended time-frame, and the early detection and modulation of plaque formation are areas of active research. Radiolabeled probes for the detection of amyloid plaques and fibrils in living subjects are important for noninvasive evaluation of AD diagnosis, progression, and differentiation of AD from other neurodegenerative diseases and age-related cognitive decline. Tritium-labeled (E,E)-1-[(3)H]-2,5-bis(4'-hydroxy-3'-carbomethoxystyryl)benzene possesses an improved level of chemical stability relative to a previously reported radioiodinated analog for radiometric quantification of Aβ plaque and tau pathology in brain tissue and in vitro studies with synthetic Aβ and tau fibrils.
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Affiliation(s)
- Sergey V Matveev
- Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky, Lexington, KY 40536-0509, United States; Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY 40536-0230, United States
| | - Stefan Kwiatkowski
- Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky, Lexington, KY 40536-0509, United States; Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596, United States
| | - Vitaliy M Sviripa
- Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky, Lexington, KY 40536-0509, United States; Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596, United States
| | - Robert C Fazio
- ViTrax Radiochemicals, 660 S. Jefferson Street, Unit E, Placentia, CA 92870, United States
| | - David S Watt
- Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky, Lexington, KY 40536-0509, United States; Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596, United States; Lucille Parker Markey Cancer Center, University of Kentucky, Lexington, KY 40536-0093, United States.
| | - Harry LeVine
- Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky, Lexington, KY 40536-0509, United States; Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY 40536-0230, United States.
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Kim SB, Bredlaw M, Farrow F. Determination of changes to TFWT and OBT concentrations in potatoes and Swiss chard as a result of preparation for human consumption. J Environ Radioact 2014; 137:18-21. [PMID: 24992239 DOI: 10.1016/j.jenvrad.2014.06.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 05/28/2014] [Accepted: 06/09/2014] [Indexed: 06/03/2023]
Abstract
Ingestion is one of the most important pathways to consider for calculating tritium dose to human beings. The objective of this study is to determine changes to TFWT and OBT concentrations in food as a result of its preparation for consumption. The contribution of OBT to the total tritium dose can be reduced by the oxidation of OBT during food preparation. The results show that preparation for consumption can result in reductions of up to 46% in TFWT concentration and 54% in OBT concentration in potato, and 22% in TFWT concentration and 57% in OBT concentration in Swiss chard.
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Affiliation(s)
- S B Kim
- Environmental Technologies Branch, Chalk River Laboratories, Atomic Energy of Canada Limited, Canada K0J 1J0.
| | - M Bredlaw
- Environmental Technologies Branch, Chalk River Laboratories, Atomic Energy of Canada Limited, Canada K0J 1J0
| | - F Farrow
- Environmental Technologies Branch, Chalk River Laboratories, Atomic Energy of Canada Limited, Canada K0J 1J0
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Valdez RA, Jiménez P, Fernández Presas AM, Aguilar L, Willms K, Romano MC. Taenia solium tapeworms synthesize corticosteroids and sex steroids in vitro. Gen Comp Endocrinol 2014; 205:62-7. [PMID: 24793221 DOI: 10.1016/j.ygcen.2014.04.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 04/20/2014] [Accepted: 04/21/2014] [Indexed: 12/19/2022]
Abstract
Cysticercosis is a disease caused by the larval stage of Taenia solium cestodes that belongs to the family Taeniidae that affects a number of hosts including humans. Taeniids tapeworms are hermaphroditic organisms that have reproductive units called proglottids that gradually mature to develop testis and ovaries. Cysticerci, the larval stage of these parasites synthesize steroids. To our knowledge there is no information about the capacity of T. solium tapeworms to metabolize progesterone or other precursors to steroid hormones. Therefore, the aim of this paper was to investigate if T. solium tapeworms were able to transform steroid precursors to corticosteroids and sex steroids. T. solium tapeworms were recovered from the intestine of golden hamsters that had been orally infected with cysticerci. The worms were cultured in the presence of tritiated progesterone or androstenedione. At the end of the experiments the culture media were analyzed by thin layer chromatography. The experiments described here showed that small amounts of testosterone were synthesized from (3)H-progesterone by complete or segmented tapeworms whereas the incubation of segmented tapeworms with (3)H-androstenedione, instead of (3)H-progesterone, improved their capacity to synthesize testosterone. In addition, the incubation of the parasites with (3)H-progesterone yielded corticosteroids, mainly deoxicorticosterone (DOC) and 11-deoxicortisol. In summary, the results described here, demonstrate that T. solium tapeworms synthesize corticosteroid and sex steroid like metabolites. The capacity of T. solium tapeworms to synthesize steroid hormones may contribute to the physiological functions of the parasite and also to their interaction with the host.
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Affiliation(s)
- R A Valdez
- Departamento de Fisiología, Biofísica y Neurociencias, CINVESTAV del I.P.N., Apdo. Postal 14-745, 07360 México, D.F., Mexico
| | - P Jiménez
- Departamento de Fisiología, Biofísica y Neurociencias, CINVESTAV del I.P.N., Apdo. Postal 14-745, 07360 México, D.F., Mexico
| | - A M Fernández Presas
- Departamento de Microbiología y Parasitología, Facultad de Medicina, UNAM, Ciudad Universitaria, México 04510, D.F., Mexico
| | - L Aguilar
- Departamento de Microbiología y Parasitología, Facultad de Medicina, UNAM, Ciudad Universitaria, México 04510, D.F., Mexico
| | - K Willms
- Departamento de Microbiología y Parasitología, Facultad de Medicina, UNAM, Ciudad Universitaria, México 04510, D.F., Mexico
| | - M C Romano
- Departamento de Fisiología, Biofísica y Neurociencias, CINVESTAV del I.P.N., Apdo. Postal 14-745, 07360 México, D.F., Mexico.
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Liu X, Matsushima A, Shimohigashi M, Shimohigashi Y. A characteristic back support structure in the bisphenol A-binding pocket in the human nuclear receptor ERRγ. PLoS One 2014; 9:e101252. [PMID: 24978476 PMCID: PMC4076284 DOI: 10.1371/journal.pone.0101252] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 06/04/2014] [Indexed: 11/18/2022] Open
Abstract
The endocrine disruptor bisphenol A (BPA) affects various genes and hormones even at merely physiological levels. We recently demonstrated that BPA binds strongly to human nuclear receptor estrogen-related receptor (ERR) γ and that the phenol-A group of BPA is in a receptacle pocket with essential amino acid residues to provide structural support at the backside. This led BPA to bind to ERRγ in an induced-fit-type binding mode, for example, with a rotated motion of Val313 to support the Tyr326-binding site. A similar binding mechanism appears to occur at the binding site of the BPA phenol-B ring. X-ray crystal analysis of the ERRγ-ligand-binding domain/BPA complex suggested that the ERRγ receptor residues Leu342, Leu345, Asn346, and Ile349 function as intrinsic binding sites of the BPA phenol-B, whereas Leu265, Leu268, Ile310, Val313, Leu324, Tyr330, Lys430, Ala431, and His434 work as structural elements to assist these binding sites. In the present study, by evaluating the mutant receptors replaced by a series of amino acids, we demonstrated that a finely assembled structural network indeed exists around the two adjacent Leu342-Asn346 and Leu345-Ile349 ridges on the same α-helix 7 (H7), constructing a part of the binding pocket structure with back support residues for the BPA phenol-B ring. The results reveal that the double-layer binding sites, namely, the ordinary ligand binding sites and their back support residues, substantiate the strong binding of BPA to ERRγ. When ERRγ-Asn346 was replaced by the corresponding Gly and Tyr in ERRα and ERRβ, respectively, the binding affinity of BPA and even 4-hydroxytamxifen (4-OHT) is much reduced. Asn346 was found to be one of the residues that make ERRγ to be exclusive to BPA.
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Affiliation(s)
- Xiaohui Liu
- Laboratory of Structure-Function Biochemistry, Department of Chemistry, Faculty of Sciences, and Risk Science Research Center, Kyushu University, Fukuoka, Japan
| | - Ayami Matsushima
- Laboratory of Structure-Function Biochemistry, Department of Chemistry, Faculty of Sciences, and Risk Science Research Center, Kyushu University, Fukuoka, Japan
| | - Miki Shimohigashi
- Division of Biology, Faculty of Science, Fukuoka University, Fukuoka, Japan
| | - Yasuyuki Shimohigashi
- Laboratory of Structure-Function Biochemistry, Department of Chemistry, Faculty of Sciences, and Risk Science Research Center, Kyushu University, Fukuoka, Japan
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Kondhare KR, Hedden P, Kettlewell PS, Farrell AD, Monaghan JM. Quantifying the impact of exogenous abscisic acid and gibberellins on pre-maturity α-amylase formation in developing wheat grains. Sci Rep 2014; 4:5355. [PMID: 24942128 DOI: 10.1007/s10681-012-0706-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 05/21/2014] [Indexed: 05/27/2023] Open
Abstract
To study the role of abscisic acid (ABA) and gibberellins (GA) in pre-maturity α-amylase (PMA) formation in developing wheat grain, two glasshouse experiments were conducted under controlled conditions in the highly PMA-susceptible genotype Rialto. The first, determined the relative efficacy of applying hormone solutions by injection into the peduncle compared to direct application to the intact grain. The second, examined the effects of each hormone, applied by either method, at mid-grain development on PMA in mature grains. In the first experiment, tritiated ABA ((3)H-ABA) and gibberellic acid ((3)H-GA3) were diluted with unlabelled ABA (100 µM) and GA3 (50 µM), respectively, and applied at mid-grain development using both methods. Spikes were harvested after 24, 48 and 72 h from application, and hormone taken up by grains was determined. After 72 h, the uptake per grain in terms of hormones applied was approximately 13% for ABA and 8% for GA3 when applied onto the grains, and approximately 17% for ABA and 5% for GA3 when applied by injection. In the second experiment, applied ABA reduced, whereas applied GA3 increased α-amylase activity. This confirmed that exogenously applied ABA and GA were absorbed in sufficient amounts to alter grain metabolism and impact on PMA.
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Affiliation(s)
- Kirtikumar R Kondhare
- Harper Adams University, Department of Crop & Environment Sciences, Newport, TF10 8NB, UK
| | - Peter Hedden
- Rothamsted Research, Department of Plant Biology & Crop Science, Harpenden, AL5 2JQ, UK
| | - Peter S Kettlewell
- Harper Adams University, Department of Crop & Environment Sciences, Newport, TF10 8NB, UK
| | - Aidan D Farrell
- The University of the West Indies, Department of Life Sciences, St. Augustine, Trinidad, West Indies
| | - James M Monaghan
- Harper Adams University, Department of Crop & Environment Sciences, Newport, TF10 8NB, UK
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Pifl C, Rajput A, Reither H, Blesa J, Cavada C, Obeso JA, Rajput AH, Hornykiewicz O. Is Parkinson's disease a vesicular dopamine storage disorder? Evidence from a study in isolated synaptic vesicles of human and nonhuman primate striatum. J Neurosci 2014; 34:8210-8. [PMID: 24920625 PMCID: PMC6608236 DOI: 10.1523/jneurosci.5456-13.2014] [Citation(s) in RCA: 118] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 05/06/2014] [Accepted: 05/07/2014] [Indexed: 12/21/2022] Open
Abstract
The cause of degeneration of nigrostriatal dopamine (DA) neurons in idiopathic Parkinson's disease (PD) is still unknown. Intraneuronally, DA is largely confined to synaptic vesicles where it is protected from metabolic breakdown. In the cytoplasm, however, free DA can give rise to formation of cytotoxic free radicals. Normally, the concentration of cytoplasmic DA is kept at a minimum by continuous pumping activity of the vesicular monoamine transporter (VMAT)2. Defects in handling of cytosolic DA by VMAT2 increase levels of DA-generated oxy radicals ultimately resulting in degeneration of DAergic neurons. Here, we isolated for the first time, DA storage vesicles from the striatum of six autopsied brains of PD patients and four controls and measured several indices of vesicular DA storage mechanisms. We found that (1) vesicular uptake of DA and binding of the VMAT2-selective label [(3)H]dihydrotetrabenazine were profoundly reduced in PD by 87-90% and 71-80%, respectively; (2) after correcting for DA nerve terminal loss, DA uptake per VMAT2 transport site was significantly reduced in PD caudate and putamen by 53 and 55%, respectively; (3) the VMAT2 transport defect appeared specific for PD as it was not present in Macaca fascicularis (7 MPTP and 8 controls) with similar degree of MPTP-induced nigrostriatal neurodegeneration; and (4) DA efflux studies and measurements of acidification in the vesicular preparations suggest that the DA storage impairment was localized at the VMAT2 protein itself. We propose that this VMAT2 defect may be an early abnormality promoting mechanisms leading to nigrostriatal DA neuron death in PD.
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Affiliation(s)
- Christian Pifl
- Center for Brain Research, Medical University of Vienna, A-1090 Vienna, Austria,
| | - Alex Rajput
- Movement Disorders Program Saskatchewan, Royal University Hospital, University of Saskatchewan, Saskatoon, Saskatchewan, SK S7N OW8, Canada
| | - Harald Reither
- Center for Brain Research, Medical University of Vienna, A-1090 Vienna, Austria
| | - Javier Blesa
- Movement Disorders Group, Neurosciences Division, CIMA, and Department of Neurology and Neurosurgery, Clinica Universidad de Navarra, E31008 Pamplona, Spain, and
| | - Carmen Cavada
- Departamento de Anatomía, Histología y Neurociencia, Facultad de Medicina, Universidad Autónoma de Madrid, E28049 Madrid, Spain
| | - José A Obeso
- Movement Disorders Group, Neurosciences Division, CIMA, and Department of Neurology and Neurosurgery, Clinica Universidad de Navarra, E31008 Pamplona, Spain, and
| | - Ali H Rajput
- Movement Disorders Program Saskatchewan, Royal University Hospital, University of Saskatchewan, Saskatoon, Saskatchewan, SK S7N OW8, Canada
| | - Oleh Hornykiewicz
- Center for Brain Research, Medical University of Vienna, A-1090 Vienna, Austria
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Kleppa MJ, Erlenwein SV, Darashchonak N, von Kaisenberg CS, von Versen-Höynck F. Hypoxia and the anticoagulants dalteparin and acetylsalicylic acid affect human placental amino acid transport. PLoS One 2014; 9:e99217. [PMID: 24901243 PMCID: PMC4047053 DOI: 10.1371/journal.pone.0099217] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 05/12/2014] [Indexed: 01/12/2023] Open
Abstract
Background Anticoagulants, e.g. low-molecular weight heparins (LMWHs) and acetylsalicylic acid (ASA) are prescribed to women at risk for pregnancy complications that are associated with impaired placentation and placental hypoxia. Beyond their role as anticoagulants these compounds exhibit direct effects on trophoblast but their impact on placental function is unknown. The amino acid transport systems A and L, which preferably transfer essential amino acids, are well-described models to study placental nutrient transport. We aimed to examine the effect of hypoxia, LMWHs and ASA on the activity of the placental amino acid transport systems A and L and associated signalling mechanisms. Methods The uptake of C14-MeAIB (system A) or H3-leucin (system L) was investigated after incubation of primary villous fragments isolated from term placentas. Villous tissue was incubated at 2% O2 (hypoxia), 8% O2 and standard culture conditions (21% O2) or at 2% O2 and 21% O2 with dalteparin or ASA. Activation of the JAK/STAT or mTOR signalling pathways was determined by Western analysis of total and phosphorylated STAT3 or Raptor. Results Hypoxia decreased system A mediated MeAIB uptake and increased system L mediated leucine uptake compared to standard culture conditions (21% O2). This was accompanied by an impairment of STAT3 and a stimulation of Raptor signalling. System L activity increased at 8% O2. Dalteparin treatment reduced system A and system L activity under normoxic conditions and ASA (1 mM) decreased system A and L transporter activity under normoxic and hypoxic conditions. Conclusions Our data underline the dependency of placental function on oxygen supply. LMWHs and ASA are not able to reverse the effects of hypoxia on placental amino acid transport. These findings and the uncovering of the signalling mechanisms in more detail will help to understand the impact of LMWHs and ASA on placental function and fetal growth.
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Affiliation(s)
- Marc-Jens Kleppa
- Department of Obstetrics and Gynecology, Hannover Medical School, Hannover, Germany
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Abstract
Spermatogenesis is known to be vulnerable to temperature. Exposures of rat testis to moderate hyperthermia result in loss of germ cells with survival of Sertoli cells (SC). Because SC provide structural and metabolic support to germ cells, our aim was to test the hypothesis that these exposures affect SC functions, thus contributing to germ cell damage. In vivo, regularly repeated exposures (one of 15 min per day, once a day during 5 days) of rat testes to 43 °C led to accumulation of neutral lipids. This SC-specific lipid function took 1-2 weeks after the last of these exposures to be maximal. In cultured SC, similar daily exposures for 15 min to 43 °C resulted in significant increase in triacylglycerol levels and accumulation of lipid droplets. After incubations with [3H]arachidonate, the labeling of cardiolipin decreased more than that of other lipid classes. Another specifically mitochondrial lipid metabolic function, fatty acid oxidation, also declined. These lipid changes suggested that temperature affects SC mitochondrial physiology, which was confirmed by significantly increased degrees of membrane depolarization and ROS production. This concurred with reduced expression of two SC-specific proteins, transferrin, and Wilms' Tumor 1 protein, markers of SC secretion and differentiation functions, respectively, and with an intense SC cytoskeletal perturbation, evident by loss of microtubule network (α-tubulin) and microfilament (f-actin) organization. Albeit temporary and potentially reversible, hyperthermia-induced SC structural and metabolic alterations may be long-lasting and/or extensive enough to respond for the decreased survival of the germ cells they normally foster.
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Affiliation(s)
- Ana S. Vallés
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) y Universidad Nacional del Sur (UNS), Bahía Blanca, Argentina
| | - Marta I. Aveldaño
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) y Universidad Nacional del Sur (UNS), Bahía Blanca, Argentina
| | - Natalia E. Furland
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) y Universidad Nacional del Sur (UNS), Bahía Blanca, Argentina
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Le Goff P, Fromm M, Vichot L, Badot PM, Guétat P. Isotopic fractionation of tritium in biological systems. Environ Int 2014; 65:116-126. [PMID: 24486969 DOI: 10.1016/j.envint.2013.12.020] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Revised: 12/31/2013] [Accepted: 12/31/2013] [Indexed: 06/03/2023]
Abstract
Isotopic fractionation of tritium is a highly relevant issue in radiation protection and requires certain radioecological considerations. Sound evaluation of this factor is indeed necessary to determine whether environmental compartments are enriched/depleted in tritium or if tritium is, on the contrary, isotopically well-distributed in a given system. The ubiquity of tritium and the standard analytical methods used to assay it may induce biases in both the measurement and the signification that is accorded to the so-called fractionation: based on an exhaustive review of the literature, we show how, sometimes large deviations may appear. It is shown that when comparing the non-exchangeable fraction of organically bound tritium (neOBT) to another fraction of tritium (e.g. tritiated water) the preparation of samples and the measurement of neOBT reported frequently led to underestimation of the ratio of tritium to hydrogen (T/H) in the non-exchangeable compartment by a factor of 5% to 50%. In the present study, corrections are proposed for most of the biological matrices studied so far. Nevertheless, the values of isotopic fractionation reported in the literature remain difficult to compare with each other, especially since the physical quantities and units often vary between authors. Some improvements are proposed to better define what should encompass the concepts of exchangeable and non-exchangeable fractions.
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Affiliation(s)
- Pierre Le Goff
- CEA Valduc, 21120 Is-sur-Tille, France; UMR CNRS 6249 Chrono-Environnement, Université de Franche-Comté, 16 route de Gray, 25030 Besançon Cedex, France.
| | - Michel Fromm
- UMR CNRS 6249 Chrono-Environnement, Université de Franche-Comté, 16 route de Gray, 25030 Besançon Cedex, France
| | | | - Pierre-Marie Badot
- UMR CNRS 6249 Chrono-Environnement, Université de Franche-Comté, 16 route de Gray, 25030 Besançon Cedex, France
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Janovics R, Bihari Á, Papp L, Dezső Z, Major Z, Sárkány KE, Bujtás T, Veres M, Palcsu L. Monitoring of tritium, 60Co and 137Cs in the vicinity of the warm water outlet of the Paks Nuclear Power Plant, Hungary. J Environ Radioact 2014; 128:20-26. [PMID: 24246753 DOI: 10.1016/j.jenvrad.2013.10.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 10/20/2013] [Accepted: 10/24/2013] [Indexed: 06/02/2023]
Abstract
Danube water, sediment and various aquatic organisms (snail, mussel, predatory and omnivorous fish) were collected upstream (at a background site) and downstream of the outlet of the warm water channel of Paks Nuclear Power Plant. Gamma emitters, tissue free-water tritium (TFWT) and total organically-bound tritium (T-OBT) measurements were performed. A slight contribution of the power plant to the natural tritium background concentration was measured in water samples from the Danube section downstream of the warm water channel. Sediment samples also contained elevated tritium concentrations, along with a detectable amount of (60)Co. In the case of biota samples, TFWT exhibited only a very slight difference compared to the tritium concentration of the Danube water, however, the OBT was higher than the tritium concentration in the Danube, independent of the origin of the samples. The elevated OBT concentration in the mollusc samples downstream of the warm water channel may be attributed to the excess emission from the nuclear power plant. The whole data set obtained was used for dose rate calculations and will be contributed to the development of the ERICA database.
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Affiliation(s)
- R Janovics
- Hertelendi Laboratory of Environmental Studies, Institute of Nuclear Research of the Hungarian Academy of Sciences, 4026 Debrecen, Hungary.
| | - Á Bihari
- Hertelendi Laboratory of Environmental Studies, Institute of Nuclear Research of the Hungarian Academy of Sciences, 4026 Debrecen, Hungary
| | - L Papp
- Hertelendi Laboratory of Environmental Studies, Institute of Nuclear Research of the Hungarian Academy of Sciences, 4026 Debrecen, Hungary
| | - Z Dezső
- Isotoptech Ltd., Debrecen, Hungary
| | - Z Major
- Hertelendi Laboratory of Environmental Studies, Institute of Nuclear Research of the Hungarian Academy of Sciences, 4026 Debrecen, Hungary
| | - K E Sárkány
- Babeş-Bolyai University, Faculty of Biology and Department of Taxonomy and Ecology, Cluj Napoca, Romania
| | - T Bujtás
- Paks Nuclear Power Plant Co., Paks, Hungary
| | - M Veres
- Isotoptech Ltd., Debrecen, Hungary
| | - L Palcsu
- Hertelendi Laboratory of Environmental Studies, Institute of Nuclear Research of the Hungarian Academy of Sciences, 4026 Debrecen, Hungary
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