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Diamandakis D, Zieminska E, Siwiec M, Tokarski K, Salinska E, Lenart J, Hess G, Lazarewicz JW. Tetrabromobisphenol A-induced depolarization of rat cerebellar granule cells: ex vivo and in vitro studies. CHEMOSPHERE 2019; 223:64-73. [PMID: 30769291 DOI: 10.1016/j.chemosphere.2019.02.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 02/05/2019] [Accepted: 02/07/2019] [Indexed: 06/09/2023]
Abstract
The brominated flame retardant tetrabromobisphenol A (TBBPA) is toxic to cultured brain neurons, and glutamate receptors partially mediate this effect; consequently, the depolarizing effect of TBBPA on neurons is to be expected, but it is yet to be actually demonstrated. The aim of this study was to detect TBBPA-evoked depolarization and identify the underlying mechanisms. The plasma membrane potential of rat cerebellar granule cells (CGC) in cerebellar slices or in primary cultures was measured using whole-cell current clamp recordings, or the fluorescent probe oxonol VI, respectively. The contribution of NMDA and AMPA receptors, voltage-gated sodium channels and intracellular calcium mobilization was tested using their selective antagonists or inhibitors. Direct interactions of TBBPA with NMDARs were tested by measuring the specific binding of radiolabeled NMDAR ligands to isolated rat cortical membrane fraction. TBBPA (25 μM) strongly depolarized CGC in cerebellar slices, and at ≥ 7.5 μM concentration-dependently depolarized primary CGC cultures. Depolarization of the primary CGC by 25 μM TBBPA was partly reduced when MK-801 was applied alone or in combination with either TTX or CNQX, or where bastadin 12 was applied in combination with ryanodine, whereas depolarization was completely prevented when MK-801, CNQX and TTX where combined. TBBPA had no effect on the specific binding of NMDAR radio-ligands to isolated cortical membranes. These results demonstrate the depolarizing effect of TBBPA on CGC, which is mainly mediated by ionotropic glutamate receptors, while voltage-gated sodium channels are also involved. We found no evidence for the direct activation of NMDARs by TBBPA.
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Affiliation(s)
- Dominik Diamandakis
- Department of Neurochemistry, Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawinskiego 5, 02-106, Warsaw, Poland.
| | - Elzbieta Zieminska
- Department of Neurochemistry, Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawinskiego 5, 02-106, Warsaw, Poland.
| | - Marcin Siwiec
- Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343, Krakow, Poland.
| | - Krzysztof Tokarski
- Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343, Krakow, Poland.
| | - Elzbieta Salinska
- Department of Neurochemistry, Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawinskiego 5, 02-106, Warsaw, Poland.
| | - Jacek Lenart
- Department of Neurochemistry, Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawinskiego 5, 02-106, Warsaw, Poland.
| | - Grzegorz Hess
- Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343, Krakow, Poland.
| | - Jerzy W Lazarewicz
- Department of Neurochemistry, Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawinskiego 5, 02-106, Warsaw, Poland.
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Zieminska E, Stafiej A, Toczylowska B, Albrecht J, Lazarewicz JW. Role of Ryanodine and NMDA Receptors in Tetrabromobisphenol A-Induced Calcium Imbalance and Cytotoxicity in Primary Cultures of Rat Cerebellar Granule Cells. Neurotox Res 2015. [PMID: 26215658 PMCID: PMC4556744 DOI: 10.1007/s12640-015-9546-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The study assessed the role of ryanodine receptors (RyRs) and NMDA receptors (NMDARs) in the Ca2+ transients and cytotoxicity induced in neurons by the brominated flame retardant tetrabromobisphenol A (TBBPA). Primary cultures of rat cerebellar granule cells (CGC) were exposed to 7.5, 10, or 25 µM TBBPA for 30 min, and cell viability was assessed after 24 h. Moreover, 45Ca uptake was measured, and changes in the intracellular Ca2+ concentration ([Ca2+]i) were studied using the fluo-3 probe. The involvement of NMDARs and RyRs was verified using the pertinent receptor antagonists, 0.5 µM MK-801 and 2.5 µM bastadin 12, which was co-applied with 200 µM ryanodine, respectively. The results show that TBBPA concentration-dependently induces an increase in [Ca2+]i. This effect was partly suppressed by the inhibitors of RyRs and NMDARs when administered separately, and completely abrogated by their combined application. A concentration-dependent activation of 45Ca uptake by TBBPA was prevented by MK-801 but not by RyR inhibitors. Application of ≥10 µM TBBPA concentration-dependently reduced neuronal viability, and this effect was only partially and to an equal degree reduced by NMDAR and RyR antagonists given either separately or in combination. Our results directly demonstrate that both the RyR-mediated release of intracellular Ca2+ and the NMDAR-mediated influx of Ca2+ into neurons participate in the mechanism of TBBPA-induced Ca2+ imbalance in CGC and play a significant, albeit not exclusive, role in the mechanisms of TBBPA cytotoxicity.
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Affiliation(s)
- Elzbieta Zieminska
- Department of Neurochemistry, Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawinskiego 5, 02-106, Warsaw, Poland,
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Niemann H, Marmann A, Lin W, Proksch P. Sponge Derived Bromotyrosines: Structural Diversity through Natural Combinatorial Chemistry. Nat Prod Commun 2015. [DOI: 10.1177/1934578x1501000143] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Sponge derived bromotyrosines are a multifaceted class of marine bioactive compounds that are important for the chemical defense of sponges but also for drug discovery programs as well as for technical applications in the field of antifouling constituents. These compounds, which are mainly accumulated by Verongid sponges, exhibit a diverse range of bioactivities including antibiotic, cytotoxic and antifouling effects. In spite of the simple biogenetic building blocks, which consist only of brominated tyrosine and tyramine units, an impressive diversity of different compounds is obtained through different linkages between these precursors and through structural modifications of the side chains and/or aromatic rings resembling strategies that are known from combinatorial chemistry. As examples for bioactive, structurally divergent bromotyrosines psammaplin A, Aplysina alkaloids featuring aerothionin, aeroplysinin-1 and the dienone, and the bastadins, including the synthetically derived hemibastadin congeners, have been selected for this review. Whereas all of these natural products are believed to be involved in the chemical defense of sponges, some of them may also be of particular relevance to drug discovery due to their interaction with specific molecular targets in eukaryotic cells. These targets involve important enzymes and receptors, such as histone deacetylases (HDAC) and DNA methyltransferases (DNMT), which are inhibited by psammaplin A, as well as ryanodine receptors that are targeted by bastadine type compounds. The hemibastadins such as the synthetically derived dibromohemibastadin are of particular interest due to their antifouling activity. For the latter, a phenoloxidase which catalyzes the bioglue formation needed for firm attachment of fouling organisms to a given substrate was identified as a molecular target. The Aplysina alkaloids finally provide a vivid example for dynamic wound induced bioconversions of natural products that generate highly efficient chemical weapons precisely when and where needed.
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Affiliation(s)
- Hendrik Niemann
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich-Heine University, 40225 Düsseldorf, Germany
| | - Andreas Marmann
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich-Heine University, 40225 Düsseldorf, Germany
| | - Wenhan Lin
- State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Health Science Center, Beijing100191, China
| | - Peter Proksch
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich-Heine University, 40225 Düsseldorf, Germany
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Ziemińska E, Stafiej A, Toczyłowska B, Lazarewicz JW. Synergistic neurotoxicity of oxygen-glucose deprivation and tetrabromobisphenol A in vitro: role of oxidative stress. Pharmacol Rep 2013; 64:1166-78. [PMID: 23238473 DOI: 10.1016/s1734-1140(12)70913-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Revised: 05/11/2012] [Indexed: 01/22/2023]
Abstract
BACKGROUND Tetrabromobisphenol A (TBBPA) is a toxic brominated flame retardant. Previous studies have demonstrated that exposure of primary cultures of rat cerebellar granule cells (CGC) to ≥ 10 μM TBBPA induces toxicity and excitotoxicity, and the underlying mechanism may involve calcium imbalance and oxidative stress. Here we examined whether the application of TBBPA at subtoxic concentrations may exacerbate acute damage of CGC challenged with oxygen-glucose deprivation (OGD), and evaluated with fluorescent indicators the involvement of calcium imbalance, mitochondrial depolarization and oxidative stress. METHODS Survival of CGC was assessed 24 h after OGD/TBBPA using fluorescent dyes. An OGD challenge lasting for 45, 60 or 75 min induced a duration-dependent injury to the neurons. RESULTS Application of 2.5, 5 or 7.5 μM TBBPA for 45 min to normoxic and glucose-containing incubation medium did not reduce the viability of cultured CGC, but this compound exacerbated the toxic effects of OGD in a concentration-dependent way. Moreover, TBBPA had a slight effect on calcium homeostasis and mitochondrial membrane potential, but significantly activated the production of reactive oxygen species in CGC. The application of H(2)O(2) at 5, 10 and 25 μM mimicked the effects of TBBPA on OGD toxicity, while 0.1 mM ascorbic acid or 1 mM glutathione ameliorated this toxicity. CONCLUSION These results suggest the involvement of oxidative stress in the synergistic neurotoxic effects of TBBPA and OGD.
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Affiliation(s)
- Elżbieta Ziemińska
- Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawińskiego 5, PL 02-106 Warszawa, Poland.
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Mathieu V, Wauthoz N, Lefranc F, Niemann H, Amighi K, Kiss R, Proksch P. Cyclic versus hemi-bastadins. pleiotropic anti-cancer effects: from apoptosis to anti-angiogenic and anti-migratory effects. Molecules 2013; 18:3543-61. [PMID: 23519198 PMCID: PMC6269779 DOI: 10.3390/molecules18033543] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 02/04/2013] [Accepted: 03/08/2013] [Indexed: 01/19/2023] Open
Abstract
Bastadins-6, -9 and -16 isolated from the marine sponge Ianthella basta displayed in vitro cytostatic and/or cytotoxic effects in six human and mouse cancer cell lines. The in vitro growth inhibitory effects of these bastadins were similar in cancer cell lines sensitive to pro-apoptotic stimuli versus cancer cell lines displaying various levels of resistance to pro-apoptotic stimuli. While about ten times less toxic than the natural cyclic bastadins, the synthetically derived 5,5'-dibromohemibastadin-1 (DBHB) displayed not only in vitro growth inhibitory activity in cancer cells but also anti-angiogenic properties. At a concentration of one tenth of its in vitro growth inhibitory concentration, DBHB displayed actual antimigratory effects in mouse B16F10 melanoma cells without any sign of cytotoxicity and/or growth inhibition. The serum concentration used in the cell culture media markedly influenced the DBHB-induced antimigratory effects in the B16F10 melanoma cell population. We are currently developing a specific inhalation formulation for DBHB enabling this compound to avoid plasmatic albumin binding through its direct delivery to the lungs to combat primary as well as secondary (metastases) tumors.
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Affiliation(s)
- Véronique Mathieu
- Laboratoire de Toxicologie, Faculté de Pharmacie, Université Libre de Bruxelles (ULB), Campus de la Plaine, Boulevard du Triomphe, 1050 Brussels, Belgium; E-Mail:
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +32-478-317-388
| | - Nathalie Wauthoz
- Laboratoire de Pharmacie Galénique et de Biopharmacie, Faculté de Pharmacie, Université Libre de Bruxelles (ULB), Campus de la Plaine, Boulevard du Triomphe, 1050 Brussels, Belgium; E-Mails: (N.W.); (K.A.)
| | - Florence Lefranc
- Service de Neurochirurgie, Hôpital Erasme, ULB, Route de Lennik, 1070 Brussels, Belgium; E-Mail:
| | - Hendrik Niemann
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich-Heine University Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany; E-Mails: (H.N.); (P.P.)
| | - Karim Amighi
- Laboratoire de Pharmacie Galénique et de Biopharmacie, Faculté de Pharmacie, Université Libre de Bruxelles (ULB), Campus de la Plaine, Boulevard du Triomphe, 1050 Brussels, Belgium; E-Mails: (N.W.); (K.A.)
| | - Robert Kiss
- Laboratoire de Toxicologie, Faculté de Pharmacie, Université Libre de Bruxelles (ULB), Campus de la Plaine, Boulevard du Triomphe, 1050 Brussels, Belgium; E-Mail:
| | - Peter Proksch
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich-Heine University Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany; E-Mails: (H.N.); (P.P.)
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Zieminska E, Lazarewicz JW, Couladouros EA, Moutsos VI, Pitsinos EN. Open-chain half-bastadins mimic the effects of cyclic bastadins on calcium homeostasis in cultured neurons. Bioorg Med Chem Lett 2008; 18:5734-7. [PMID: 18851910 DOI: 10.1016/j.bmcl.2008.09.080] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2008] [Revised: 09/22/2008] [Accepted: 09/23/2008] [Indexed: 12/24/2022]
Abstract
Constraining the catechol aryl ether moiety of bastadins by incorporation into a macrocyle is not necessary in order to mimic the effects of these marine natural products on neuronal calcium homeostasis. Simple, acyclic analogs that embody the 'western' or 'eastern' parts of bastadins were found to evoke comparable responses with bastadin 5.
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Affiliation(s)
- Elzbieta Zieminska
- Medical Research Centre, Polish Academy of Sciences, Pawinskiego 5, 02-106 Warsaw, Poland
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