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Boubaker G, Bernal A, Vigneswaran A, Imhof D, de Sousa MCF, Hänggeli KPA, Haudenschild N, Furrer J, Păunescu E, Desiatkina O, Hemphill A. In vitro and in vivo activities of a trithiolato-diRuthenium complex conjugated with sulfadoxine against the apicomplexan parasite Toxoplasma gondii. Int J Parasitol Drugs Drug Resist 2024; 25:100544. [PMID: 38703737 PMCID: PMC11087982 DOI: 10.1016/j.ijpddr.2024.100544] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 04/17/2024] [Accepted: 04/24/2024] [Indexed: 05/06/2024]
Abstract
Organometallic compounds, including Ruthenium complexes, have been widely developed as anti-cancer chemotherapeutics, but have also attracted much interest as potential anti-parasitic drugs. Recently hybrid drugs composed of organometallic Ruthenium moieties that were complexed to different antimicrobial agents were synthesized. One of these compounds, a trithiolato-diRuthenium complex (RU) conjugated to sulfadoxine (SDX), inhibited proliferation of Toxoplasma gondii tachyzoites grown in human foreskin fibroblast (HFF) monolayers with an IC50 < 150 nM, while SDX and the non-modified RU complex applied either individually or as an equimolar mixture were much less potent. In addition, conjugation of SDX to RU lead to decreased HFF cytotoxicity. RU-SDX did not impair the in vitro proliferation of murine splenocytes at concentrations ranging from 0.1 to 0.5 μM but had an impact at 2 μM, and induced zebrafish embryotoxicity at 20 μM, but not at 2 or 0.2 μM. RU-SDX acted parasitostatic but not parasiticidal, and induced transient ultrastructural changes in the mitochondrial matrix of tachyzoites early during treatment. While other compounds that target the mitochondrion such as the uncouplers FCCP and CCCP and another trithiolato-Ruthenium complex conjugated to adenine affected the mitochondrial membrane potential, no such effect was detected for RU-SDX. Evaluation of the in vivo efficacy of RU-SDX in a murine T. gondii oocyst infection model comprised of non-pregnant outbred CD1 mice showed no effects on the cerebral parasite burden, but reduced parasite load in the eyes and in heart tissue.
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Affiliation(s)
- Ghalia Boubaker
- Institute of Parasitology, Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern. Länggass-Strasse 122, 3012, Bern, Switzerland.
| | - Alice Bernal
- Institute of Parasitology, Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern. Länggass-Strasse 122, 3012, Bern, Switzerland.
| | - Anitha Vigneswaran
- Institute of Parasitology, Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern. Länggass-Strasse 122, 3012, Bern, Switzerland.
| | - Dennis Imhof
- Institute of Parasitology, Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern. Länggass-Strasse 122, 3012, Bern, Switzerland.
| | - Maria Cristina Ferreira de Sousa
- Institute of Parasitology, Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern. Länggass-Strasse 122, 3012, Bern, Switzerland; Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, Switzerland.
| | - Kai Pascal Alexander Hänggeli
- Institute of Parasitology, Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern. Länggass-Strasse 122, 3012, Bern, Switzerland; Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, Switzerland.
| | - Noé Haudenschild
- Institute of Parasitology, Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern. Länggass-Strasse 122, 3012, Bern, Switzerland.
| | - Julien Furrer
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland.
| | - Emilia Păunescu
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland.
| | - Oksana Desiatkina
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland.
| | - Andrew Hemphill
- Institute of Parasitology, Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern. Länggass-Strasse 122, 3012, Bern, Switzerland.
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Bigler P, Gjuroski I, Chakif D, Furrer J. A Versatile Broadband Attached Proton Test Experiment for Routine 13C Nuclear Magnetic Resonance Spectroscopy. Molecules 2024; 29:809. [PMID: 38398560 PMCID: PMC10893545 DOI: 10.3390/molecules29040809] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 02/06/2024] [Accepted: 02/07/2024] [Indexed: 02/25/2024] Open
Abstract
The proposed broadband attached proton test sequence allows the user to easily record 13C nuclear magnetic resonance multiplicity-edited and quaternary-carbon-only spectra. Compared to earlier attached proton test experiments, it preserves both a tolerance for wide ranges of one-bond-coupling constant values and the effective suppression of residual CHn signals in the quaternary-carbon-only spectra. The recording of edited spectra or quaternary-carbon-only spectra is made easy by a single, user-controllable constant. These attributes make the broadband attached proton test experiment attractive for the 13C analysis of small molecules, including spectral editing, particularly in high-throughput analysis laboratories.
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Affiliation(s)
- Peter Bigler
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland; (I.G.); (D.C.)
| | | | | | - Julien Furrer
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland; (I.G.); (D.C.)
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Bugnon Q, Melendez C, Desiatkina O, Fayolles de Chaptes L, Holzer I, Păunescu E, Hilty M, Furrer J. In vitro antibacterial activity of dinuclear thiolato-bridged ruthenium(II)-arene compounds. Microbiol Spectr 2023; 11:e0095423. [PMID: 37815336 PMCID: PMC10714934 DOI: 10.1128/spectrum.00954-23] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 08/28/2023] [Indexed: 10/11/2023] Open
Abstract
IMPORTANCE The in vitro assessment of diruthenium(II)-arene compounds against Escherichia coli, Streptococcus pneumoniae, and Staphylococcus aureus showed a significant antibacterial activity of some compounds against S. pneumoniae, with minimum inhibitory concentration (MIC) values ranging from 1.3 to 2.6 µM, and a medium activity against E. coli, with MIC of 25 µM. The nature of the substituents anchored on the bridging thiols and the compounds molecular weight appear to significantly influence the antibacterial activity. Fluorescence microscopy showed that these ruthenium compounds enter the bacteria and do not accumulate in the cell wall of gram-positive bacteria. These diruthenium(II)-arene compounds exhibit promising activity against S. aureus and S. pneumoniae and deserve to be considered for further studies, especially the compounds bearing larger benzo-fused lactam substituents.
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Affiliation(s)
- Quentin Bugnon
- Department of Medicine, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
- Department of Chemistry, Biochemistry and Pharmaceuticals Sciences, University of Bern, Bern, Switzerland
| | - Camilo Melendez
- Department of Chemistry, Biochemistry and Pharmaceuticals Sciences, University of Bern, Bern, Switzerland
| | - Oksana Desiatkina
- Department of Chemistry, Biochemistry and Pharmaceuticals Sciences, University of Bern, Bern, Switzerland
| | - Louis Fayolles de Chaptes
- Department of Chemistry, Biochemistry and Pharmaceuticals Sciences, University of Bern, Bern, Switzerland
| | - Isabelle Holzer
- Department of Chemistry, Biochemistry and Pharmaceuticals Sciences, University of Bern, Bern, Switzerland
| | - Emilia Păunescu
- Department of Chemistry, Biochemistry and Pharmaceuticals Sciences, University of Bern, Bern, Switzerland
| | - Markus Hilty
- Department of Medicine, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Julien Furrer
- Department of Chemistry, Biochemistry and Pharmaceuticals Sciences, University of Bern, Bern, Switzerland
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Werren JP, Mostacci N, Gjuroski I, Holivololona L, Troxler LJ, Hathaway LJ, Furrer J, Hilty M. Carbon source-dependent capsule thickness regulation in Streptococcus pneumoniae. Front Cell Infect Microbiol 2023; 13:1279119. [PMID: 38094742 PMCID: PMC10716237 DOI: 10.3389/fcimb.2023.1279119] [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] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 10/30/2023] [Indexed: 12/18/2023] Open
Abstract
Background The polysaccharide capsule of Streptococcus pneumoniae plays a major role in virulence, adherence to epithelial cells, and overall survival of the bacterium in the human host. Galactose, mannose, and N-acetylglucosamine (GlcNAc) are likely to be relevant for metabolization in the nasopharynx, while glucose is the primary carbon source in the blood. In this study, we aim to further the understanding of the influence of carbon sources on pneumococcal growth, capsule biosynthesis, and subsequent adherence potential. Methods We tested the growth behavior of clinical wild-type and capsule knockout S. pneumoniae strains, using galactose, GlcNAc, mannose, and glucose as carbon source for growth. We measured capsule thickness and quantified capsule precursors by fluorescein isothiocyanate (FITC)-dextran exclusion assays and 31P-nuclear magnetic resonance measurements, respectively. We also performed epithelial adherence assays using Detroit 562 cells and performed a transcriptome analysis (RNA sequencing). Results We observed a reduced growth in galactose, mannose, and GlcNAc compared to growth in glucose and found capsular size reductions in mannose and GlcNAc compared to galactose and glucose. Additionally, capsular precursor measurements of uridine diphosphate-(UDP)-glucose and UDP-galactose showed less accumulation of precursors in GlcNAc or mannose than in glucose and galactose, indicating a possible link with the received capsular thickness measurements. Epithelial adherence assays showed an increase in adherence potential for a pneumococcal strain, when grown in mannose compared to glucose. Finally, transcriptome analysis of four clinical isolates revealed not only strain specific but also common carbon source-specific gene expression. Conclusion Our findings may indicate a careful adaption of the lifestyle of S. pneumoniae according to the monosaccharides encountered in the respective human niche.
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Affiliation(s)
- Joel P. Werren
- Institute for Infectious Diseases, Faculty of Medicine, University of Bern, Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Nadja Mostacci
- Institute for Infectious Diseases, Faculty of Medicine, University of Bern, Bern, Switzerland
| | - Ilche Gjuroski
- Department of Chemistry, Biochemistry and Pharmacy, University of Bern, Bern, Switzerland
| | - Lalaina Holivololona
- Institute for Infectious Diseases, Faculty of Medicine, University of Bern, Bern, Switzerland
| | - Lukas J. Troxler
- Institute for Infectious Diseases, Faculty of Medicine, University of Bern, Bern, Switzerland
| | - Lucy J. Hathaway
- Institute for Infectious Diseases, Faculty of Medicine, University of Bern, Bern, Switzerland
| | - Julien Furrer
- Department of Chemistry, Biochemistry and Pharmacy, University of Bern, Bern, Switzerland
| | - Markus Hilty
- Institute for Infectious Diseases, Faculty of Medicine, University of Bern, Bern, Switzerland
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Bordon G, Ramakrishna SN, Edalat SG, Eugster R, Arcifa A, Vermathen M, Aleandri S, Bertoncelj MF, Furrer J, Vermathen P, Isa L, Crockett R, Distler O, Luciani P. Liposomal aggregates sustain the release of rapamycin and protect cartilage from friction. J Colloid Interface Sci 2023; 650:1659-1670. [PMID: 37494862 DOI: 10.1016/j.jcis.2023.07.087] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 07/07/2023] [Accepted: 07/13/2023] [Indexed: 07/28/2023]
Abstract
Liposomes show promise as biolubricants for damaged cartilage, but their small size results in low joint and cartilage retention. We developed a zinc ion-based liposomal drug delivery system for local osteoarthritis therapy, focusing on sustained release and tribological protection from phospholipid lubrication properties. Our strategy involved inducing aggregation of negatively charged liposomes with zinc ions to extend rapamycin (RAPA) release and improve cartilage lubrication. Liposomal aggregation occurred within 10 min and was irreversible, facilitating excess cation removal. The aggregates extended RAPA release beyond free liposomes and displayed irregular morphology influenced by RAPA. At nearly 100 µm, the aggregates were large enough to exceed the previously reported size threshold for increased joint retention. Tribological assessment on silicon surfaces and ex vivo porcine cartilage revealed the system's excellent protective ability against friction at both nano- and macro-scales. Moreover, RAPA was shown to attenuate the fibrotic response in human OA synovial fibroblasts. Our findings suggest the zinc ion-based liposomal drug delivery system has potential to enhance OA therapy through extended release and cartilage tribological protection, while also illustrating the impact of a hydrophobic drug like RAPA on liposome aggregation and morphology.
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Affiliation(s)
- Gregor Bordon
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Shivaprakash N Ramakrishna
- Laboratory for Soft Materials and Interfaces, Department of Materials, ETH Zurich, Vladimir- Prelog-Weg 1-5/10, 8093 Zurich, Switzerland
| | - Sam G Edalat
- Center of Experimental Rheumatology, Department of Rheumatology, University Hospital Zurich, University of Zurich, Wagistrasse 14, 8952 Schlieren, Switzerland
| | - Remo Eugster
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Andrea Arcifa
- Laboratory for Surface Science and Coating Technologies, EMPA, Uberlandstrasse 129, 8600 Dubendorf, Switzerland
| | - Martina Vermathen
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Simone Aleandri
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | | | - Julien Furrer
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Peter Vermathen
- Magnetic Resonance Methodology, Institute of Diagnostic and Interventional Neuroradiology, University & Inselspital Bern, sitem-insel AG, Freiburgstrasse 3, 3010 Bern, Switzerland
| | - Lucio Isa
- Laboratory for Soft Materials and Interfaces, Department of Materials, ETH Zurich, Vladimir- Prelog-Weg 1-5/10, 8093 Zurich, Switzerland
| | - Rowena Crockett
- Laboratory for Surface Science and Coating Technologies, EMPA, Uberlandstrasse 129, 8600 Dubendorf, Switzerland
| | - Oliver Distler
- Center of Experimental Rheumatology, Department of Rheumatology, University Hospital Zurich, University of Zurich, Wagistrasse 14, 8952 Schlieren, Switzerland
| | - Paola Luciani
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland.
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Holzer I, Desiatkina O, Anghel N, Johns SK, Boubaker G, Hemphill A, Furrer J, Păunescu E. Synthesis and Antiparasitic Activity of New Trithiolato-Bridged Dinuclear Ruthenium(II)-arene-carbohydrate Conjugates. Molecules 2023; 28:902. [PMID: 36677958 PMCID: PMC9865825 DOI: 10.3390/molecules28020902] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [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] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 01/09/2023] [Accepted: 01/11/2023] [Indexed: 01/18/2023] Open
Abstract
Eight novel carbohydrate-tethered trithiolato dinuclear ruthenium(II)-arene complexes were synthesized using CuAAC ‘click’ (Cu(I)-catalyzed azide-alkyne cycloaddition) reactions, and there in vitro activity against transgenic T. gondii tachyzoites constitutively expressing β-galactosidase (T. gondii β-gal) and in non-infected human foreskin fibroblasts, HFF, was determined at 0.1 and 1 µM. When evaluated at 1 µM, seven diruthenium-carbohydrate conjugates strongly impaired parasite proliferation by >90%, while HFF viability was retained at 50% or more, and they were further subjected to the half-maximal inhibitory concentration (IC50) measurement on T. gondii β-gal. Results revealed that the biological activity of the hybrids was influenced both by the nature of the carbohydrate (glucose vs. galactose) appended on ruthenium complex and the type/length of the linker between the two units. 23 and 26, two galactose-based diruthenium conjugates, exhibited low IC50 values and reduced effect on HFF viability when applied at 2.5 µM (23: IC50 = 0.032 µM/HFF viability 92% and 26: IC50 = 0.153 µM/HFF viability 97%). Remarkably, compounds 23 and 26 performed significantly better than the corresponding carbohydrate non-modified diruthenium complexes, showing that this type of conjugates are a promising approach for obtaining new antiparasitic compounds with reduced toxicity.
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Affiliation(s)
- Isabelle Holzer
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Oksana Desiatkina
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Nicoleta Anghel
- Institute of Parasitology Vetsuisse Faculty, University of Bern, Länggass-Strasse 122, 3012 Bern, Switzerland
| | - Serena K. Johns
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
- School of Chemistry, Cardiff University, Park Place, Cardiff CF103AT, UK
| | - Ghalia Boubaker
- Institute of Parasitology Vetsuisse Faculty, University of Bern, Länggass-Strasse 122, 3012 Bern, Switzerland
| | - Andrew Hemphill
- Institute of Parasitology Vetsuisse Faculty, University of Bern, Länggass-Strasse 122, 3012 Bern, Switzerland
| | - Julien Furrer
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Emilia Păunescu
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
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Desiatkina O, Anghel N, Boubaker G, Amdouni Y, Hemphill A, Furrer J, Păunescu E. Trithiolato-Bridged Dinuclear Ruthenium(II)-Arene Conjugates Tethered with Lipophilic Units: Synthesis and Toxoplasma gondii Antiparasitic Activity. J Organomet Chem 2023. [DOI: 10.1016/j.jorganchem.2023.122624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Desiatkina O, Boubaker G, Anghel N, Amdouni Y, Hemphill A, Furrer J, Păunescu E. Synthesis, Photophysical Properties and Biological Evaluation of New Conjugates BODIPY: Dinuclear Trithiolato-Bridged Ruthenium(II)-Arene Complexes. Chembiochem 2022; 23:e202200536. [PMID: 36219484 DOI: 10.1002/cbic.202200536] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 10/11/2022] [Indexed: 01/25/2023]
Abstract
The synthesis, photophysical properties and antiparasitic efficacy against Toxoplasma gondii β-gal (RH strain tachyzoites expressing β-galactosidase) grown in human foreskin fibroblast monolayers (HFF) of a series of 15 new conjugates BODIPY-trithiolato-bridged dinuclear ruthenium(II)-arene complexes are reported (BODIPY=4,4-difluoro-4-bora-3a,4a-diaza-s-indacene, derivatives used as fluorescent markers). The influence of the bond type (amide vs. ester), as well as that of the length and nature (alkyl vs. aryl) of the spacer between the dye and the diruthenium(II) complex moiety, on fluorescence and biological activity were evaluated. The assessed photophysical properties revealed that despite an important fluorescence quenching effect observed after conjugating the BODIPY to the diruthenium unit, the hybrids could nevertheless be used as fluorescent tracers. Although the antiparasitic activity of this series of conjugates appears limited, the compounds demonstrate potential as fluorescent probes for investigating the intracellular trafficking of trithiolato-bridged dinuclear Ru(II)-arene complexes in vitro.
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Affiliation(s)
- Oksana Desiatkina
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Ghalia Boubaker
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Länggassstrasse 122, 3012, Bern, Switzerland
| | - Nicoleta Anghel
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Länggassstrasse 122, 3012, Bern, Switzerland
| | - Yosra Amdouni
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Länggassstrasse 122, 3012, Bern, Switzerland.,Laboratoire de Parasitologie, Université de la Manouba, Institution de la Recherche et de l'Enseignement Supérieur Agricoles, École Nationale de Médecine Vétérinaire de Sidi Thabet, 2020, Sidi Thabet, Tunisia
| | - Andrew Hemphill
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Länggassstrasse 122, 3012, Bern, Switzerland
| | - Julien Furrer
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Emilia Păunescu
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
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Desiatkina O, Mösching M, Anghel N, Boubaker G, Amdouni Y, Hemphill A, Furrer J, Păunescu E. New Nucleic Base-Tethered Trithiolato-Bridged Dinuclear Ruthenium(II)-Arene Compounds: Synthesis and Antiparasitic Activity. Molecules 2022; 27:molecules27238173. [PMID: 36500266 PMCID: PMC9738179 DOI: 10.3390/molecules27238173] [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] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 11/18/2022] [Accepted: 11/22/2022] [Indexed: 11/25/2022]
Abstract
Aiming toward compounds with improved anti-Toxoplasma activity by exploiting the parasite auxotrophies, a library of nucleobase-tethered trithiolato-bridged dinuclear ruthenium(II)-arene conjugates was synthesized and evaluated. Structural features such as the type of nucleobase and linking unit were progressively modified. For comparison, diruthenium hybrids with other type of molecules were also synthesized and assessed. A total of 37 compounds (diruthenium conjugates and intermediates) were evaluated in a primary screening for in vitro activity against transgenic Toxoplasma gondii tachyzoites constitutively expressing β-galactosidase (T. gondii β-gal) at 0.1 and 1 µM. In parallel, the cytotoxicity in non-infected host cells (human foreskin fibroblasts, HFF) was determined by alamarBlue assay. Twenty compounds strongly impairing parasite proliferation with little effect on HFF viability were subjected to T. gondii β-gal half maximal inhibitory concentration determination (IC50) and their toxicity for HFF was assessed at 2.5 µM. Two promising compounds were identified: 14, ester conjugate with 9-(2-oxyethyl)adenine, and 36, a click conjugate bearing a 2-(4-(hydroxymethyl)-1H-1,2,3-triazol-1-yl)methyl substituent, with IC50 values of 0.059 and 0.111 µM respectively, significantly lower compared to pyrimethamine standard (IC50 = 0.326 µM). Both 14 and 36 exhibited low toxicity against HFF when applied at 2.5 µM and are candidates for potential treatment options in a suitable in vivo model.
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Affiliation(s)
- Oksana Desiatkina
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Martin Mösching
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Nicoleta Anghel
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Länggass-Strasse 122, 3012 Bern, Switzerland
| | - Ghalia Boubaker
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Länggass-Strasse 122, 3012 Bern, Switzerland
| | - Yosra Amdouni
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Länggass-Strasse 122, 3012 Bern, Switzerland
- Laboratoire de Parasitologie, Institution de la Recherche et de l'Enseignement Supérieur Agricoles, Université de la Manouba, École Nationale de Médecine Vétérinaire de Sidi Thabet, Sidi Thabet 2020, Tunisia
| | - Andrew Hemphill
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Länggass-Strasse 122, 3012 Bern, Switzerland
| | - Julien Furrer
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Emilia Păunescu
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
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Anghel N, Müller J, Serricchio M, Jelk J, Bütikofer P, Boubaker G, Imhof D, Ramseier J, Desiatkina O, Păunescu E, Braga-Lagache S, Heller M, Furrer J, Hemphill A. Cellular and Molecular Targets of Nucleotide-Tagged Trithiolato-Bridged Arene Ruthenium Complexes in the Protozoan Parasites Toxoplasma gondii and Trypanosoma brucei. Int J Mol Sci 2021; 22:ijms221910787. [PMID: 34639127 PMCID: PMC8509533 DOI: 10.3390/ijms221910787] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 09/29/2021] [Accepted: 10/02/2021] [Indexed: 12/23/2022] Open
Abstract
Toxoplasma gondii is an apicomplexan parasite that infects and proliferates within many different types of host cells and infects virtually all warm-blooded animals and humans. Trypanosoma brucei is an extracellular kinetoplastid that causes human African trypanosomiasis and Nagana disease in cattle, primarily in rural sub-Saharan Africa. Current treatments against both parasites have limitations, e.g., suboptimal efficacy and adverse side effects. Here, we investigate the potential cellular and molecular targets of a trithiolato-bridged arene ruthenium complex conjugated to 9-(2-hydroxyethyl)-adenine (1), which inhibits both parasites with IC50s below 10−7 M. Proteins that bind to 1 were identified using differential affinity chromatography (DAC) followed by shotgun-mass spectrometry. A trithiolato-bridged ruthenium complex decorated with hypoxanthine (2) and 2-hydroxyethyl-adenine (3) were included as controls. Transmission electron microscopy (TEM) revealed distinct ultrastructural modifications in the mitochondrion induced by (1) but not by (2) and (3) in both species. DAC revealed 128 proteins in T. gondii and 46 proteins in T. brucei specifically binding to 1 but not 2 or 3. In T. gondii, the most abundant was a protein with unknown function annotated as YOU2. This protein is a homolog to the human mitochondrial inner membrane translocase subunit Tim10. In T. brucei, the most abundant proteins binding specifically to 1 were mitochondrial ATP-synthase subunits. Exposure of T. brucei bloodstream forms to 1 resulted in rapid breakdown of the ATP-synthase complex. Moreover, both datasets contained proteins involved in key steps of metabolism and nucleic acid binding proteins.
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Affiliation(s)
- Nicoleta Anghel
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland; (N.A.); (G.B.); (D.I.); (J.R.)
| | - Joachim Müller
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland; (N.A.); (G.B.); (D.I.); (J.R.)
- Correspondence: (J.M.); (A.H.)
| | - Mauro Serricchio
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012 Bern, Switzerland; (M.S.); (J.J.); (P.B.)
| | - Jennifer Jelk
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012 Bern, Switzerland; (M.S.); (J.J.); (P.B.)
| | - Peter Bütikofer
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012 Bern, Switzerland; (M.S.); (J.J.); (P.B.)
| | - Ghalia Boubaker
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland; (N.A.); (G.B.); (D.I.); (J.R.)
| | - Dennis Imhof
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland; (N.A.); (G.B.); (D.I.); (J.R.)
| | - Jessica Ramseier
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland; (N.A.); (G.B.); (D.I.); (J.R.)
| | - Oksana Desiatkina
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, 3012 Bern, Switzerland; (O.D.); (E.P.); (J.F.)
| | - Emilia Păunescu
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, 3012 Bern, Switzerland; (O.D.); (E.P.); (J.F.)
| | - Sophie Braga-Lagache
- Proteomics and Mass Spectrometry Core Facility, Department for BioMedical Research (DBMR), University of Bern, 3012 Bern, Switzerland; (S.B.-L.); (M.H.)
| | - Manfred Heller
- Proteomics and Mass Spectrometry Core Facility, Department for BioMedical Research (DBMR), University of Bern, 3012 Bern, Switzerland; (S.B.-L.); (M.H.)
| | - Julien Furrer
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, 3012 Bern, Switzerland; (O.D.); (E.P.); (J.F.)
| | - Andrew Hemphill
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland; (N.A.); (G.B.); (D.I.); (J.R.)
- Correspondence: (J.M.); (A.H.)
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11
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Colombo G, Attilio Ardizzoia G, Furrer J, Therrien B, Brenna S. Driving the Emission Towards Blue by Controlling the HOMO-LUMO Energy Gap in BF 2 -Functionalized 2-(Imidazo[1,5-a]pyridin-3-yl)phenols. Chemistry 2021; 27:12380-12387. [PMID: 34160858 PMCID: PMC8456857 DOI: 10.1002/chem.202101520] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Indexed: 01/25/2023]
Abstract
Several boron compounds with 2-(imidazo[1,5-a]pyridin-3-yl)phenols, differentiated by the nature of the substituent (R) in the para position of the hydroxy group, have been synthesized and thoroughly characterized both in solution (1 H, 13 C, 11 B, 19 F NMR) and in the solid state (X-ray). All derivatives displayed attractive photophysical properties like very high Stokes shift, high fluorescence quantum yields and a good photostability in solution. Time-Dependent Density Functional Theory (TD-DFT) calculations allowed to define the main electronic transitions as intra ligand transitions (1 ILT), which was corroborated by the Natural Transition Orbitals (NTOs) shapes. The HOMO-LUMO energy gap was correlated to the electronic properties of the substituent R on the phenolic ring, as quantified by its σp Hammett constant.
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Affiliation(s)
- Gioele Colombo
- Department of Science and High TechnologyUniversity of InsubriaVia Valleggio, 922100ComoItaly
- Consorzio Interuniversitario Reattività Chimica e Catalisi (CIRCC)BariItaly
| | - G. Attilio Ardizzoia
- Department of Science and High TechnologyUniversity of InsubriaVia Valleggio, 922100ComoItaly
- Consorzio Interuniversitario Reattività Chimica e Catalisi (CIRCC)BariItaly
| | - Julien Furrer
- Department für ChemieBiochemie und PharmazieUniversität BernFreiestrasse 33012BernSwitzerland
| | - Bruno Therrien
- Institute of ChemistryUniversité de NeuchâtelAvenue de Bellevaux 512000NeuchâtelSwitzerland
| | - Stefano Brenna
- Department of Science and High TechnologyUniversity of InsubriaVia Valleggio, 922100ComoItaly
- Consorzio Interuniversitario Reattività Chimica e Catalisi (CIRCC)BariItaly
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12
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Păunescu E, Boubaker G, Desiatkina O, Anghel N, Amdouni Y, Hemphill A, Furrer J. The quest of the best - A SAR study of trithiolato-bridged dinuclear Ruthenium(II)-Arene compounds presenting antiparasitic properties. Eur J Med Chem 2021; 222:113610. [PMID: 34144354 DOI: 10.1016/j.ejmech.2021.113610] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 05/18/2021] [Accepted: 06/01/2021] [Indexed: 12/31/2022]
Abstract
A structure activity relationship (SAR) study of a library of 56 compounds (54 ruthenium and 2 osmium derivatives) based on the trithiolato-bridged dinuclear ruthenium(II)-arene scaffold (general formula [(η6-arene)2Ru2(μ2-SR)3]+, symmetric and [(η6-arene)2Ru2(μ2-SR1)2(μ2-SR2)]+, mixed, respectively) is reported. The 56 compounds (of which 34 are newly designed drug candidates) were synthesized by introducing chemical modifications at the level of bridge thiols, and they were grouped into eight families according to their structural features. The selected fittings were guided by previous results and focused on a fine-tuning of the physico-chemical and steric properties. Newly synthesized complexes were characterized by NMR spectroscopy, mass spectrometry and elemental analysis, and four single-crystal X-ray structures were obtained. The in vitro biological assessment of the compounds was realized by applying a three-step screening cascade: (i) evaluation of the activity against Toxoplasma gondii RH strain tachyzoites expressing β-galactosidase (T. gondii-β-gal) grown in human foreskin fibroblast monolayers (HFF) and assessment of toxicity in non-infected HFF host cells; (ii) dose-response assays using selected compound, and (iii) studies on the effects in murine splenocytes. A primary screening was performed at 1 and 0.1 μM, and resulted in the selection of 39 compounds that inhibited parasite proliferation at 1 μM by more than 95% and reduced the viability of HFF by less than 49%. In the secondary screening, dose-response assays showed that the selected compounds exhibited half maximal inhibitory concentration (IC50) values for T. gondii-β-gal between 0.01 μM and 0.45 μM, with 30 compounds displaying an IC50 lower than 0.1 μM. When applied to non-infected HFF monolayers at 2.5 μM, 8 compounds caused more than 90% and 31 compounds more than 30% viability impairment. The tertiary screening included 14 compounds that did not cause HFF viability loss higher than 50% at 2.5 μM. These derivatives were assessed for potential immunosuppressive activities. First, splenocyte viability was assessed after treatment of cells with concanavalin A (ConA) and lipopolysaccharide (LPS) with compounds applied at 0.1 and 0.5 μM. Subsequently, the 5 compounds exhibiting the lowest splenocyte toxicity were further evaluated for their potential to inhibit B and T cell proliferation. Overall, compound 55 [(η6-p-MeC6H4Pri)2Ru2(μ2-SC6H4-o-CF3)2(μ2-SC6H4-p-OH)]Cl exhibited the most favorable features, and will be investigated as a scaffold for further optimization in terms of anti-parasitic efficacy and drug-like properties.
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Affiliation(s)
- Emilia Păunescu
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland.
| | - Ghalia Boubaker
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Länggass-Strasse 122, 3012, Bern, Switzerland
| | - Oksana Desiatkina
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Nicoleta Anghel
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Länggass-Strasse 122, 3012, Bern, Switzerland
| | - Yosra Amdouni
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Länggass-Strasse 122, 3012, Bern, Switzerland; Laboratoire de Parasitologie, Université de la Manouba, Institution de la Recherche et de l'Enseignement Supérieur Agricoles, École Nationale de Médecine Vétérinaire de Sidi Thabet, Sidi Thabet, 2020, Tunisia
| | - Andrew Hemphill
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Länggass-Strasse 122, 3012, Bern, Switzerland.
| | - Julien Furrer
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland.
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Gjuroski I, Furrer J, Vermathen M. Probing the Interactions of Porphyrins with Macromolecules Using NMR Spectroscopy Techniques. Molecules 2021; 26:1942. [PMID: 33808335 PMCID: PMC8037866 DOI: 10.3390/molecules26071942] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [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: 02/24/2021] [Revised: 03/22/2021] [Accepted: 03/24/2021] [Indexed: 12/11/2022] Open
Abstract
Porphyrinic compounds are widespread in nature and play key roles in biological processes such as oxygen transport in blood, enzymatic redox reactions or photosynthesis. In addition, both naturally derived as well as synthetic porphyrinic compounds are extensively explored for biomedical and technical applications such as photodynamic therapy (PDT) or photovoltaic systems, respectively. Their unique electronic structures and photophysical properties make this class of compounds so interesting for the multiple functions encountered. It is therefore not surprising that optical methods are typically the prevalent analytical tool applied in characterization and processes involving porphyrinic compounds. However, a wealth of complementary information can be obtained from NMR spectroscopic techniques. Based on the advantage of providing structural and dynamic information with atomic resolution simultaneously, NMR spectroscopy is a powerful method for studying molecular interactions between porphyrinic compounds and macromolecules. Such interactions are of special interest in medical applications of porphyrinic photosensitizers that are mostly combined with macromolecular carrier systems. The macromolecular surrounding typically stabilizes the encapsulated drug and may also modify its physical properties. Moreover, the interaction with macromolecular physiological components needs to be explored to understand and control mechanisms of action and therapeutic efficacy. This review focuses on such non-covalent interactions of porphyrinic drugs with synthetic polymers as well as with biomolecules such as phospholipids or proteins. A brief introduction into various NMR spectroscopic techniques is given including chemical shift perturbation methods, NOE enhancement spectroscopy, relaxation time measurements and diffusion-ordered spectroscopy. How these NMR tools are used to address porphyrin-macromolecule interactions with respect to their function in biomedical applications is the central point of the current review.
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Affiliation(s)
| | | | - Martina Vermathen
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland; (I.G.); (J.F.)
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Bigler P, Furrer J. Simplifying LR-HSQC spectra using a triple-quantum filter: The LR-HTQC experiment. Magn Reson Chem 2021; 59:52-60. [PMID: 33411358 DOI: 10.1002/mrc.5078] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/14/2020] [Accepted: 07/19/2020] [Indexed: 06/12/2023]
Abstract
Long-range heteronuclear single quantum correlation (LR-HSQC) experiments may be applied for detecting long-range correlations but suffer from two disadvantages, common to all heteronuclear long-range correlation experiments: (i) The information density in LR-HSQC spectra may be too high to be used directly without "filtering out" shorter range correlations, and (ii) often, substantial differences in intensity among cross peaks exist, potentially hampering the visualization of weak, often crucial cross peaks. In this contribution, we propose a modified LR-HSQC experiment, the LR-HTQC experiment (Long-Range Heteronuclear Triple Quantum Correlation) that partially solves the problems aforementioned. We show theoretically and experimentally that the LR-HTQC experiment removes the intense cross peaks of CH spin pairs, substantially reduces the medium intensity of cross peaks originating from CHH' spin systems, whereas the typically weak intensity of cross peaks of CHH'H″ and C(H)n, n > 3 spin systems is less affected. Consequently, the LR-HTQC experiment affords simplified long-range heteronuclear shift correlation spectra and scales down large intensity differences among different types of cross peaks, although a certain general reduction of signal intensities has to be accepted.
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Affiliation(s)
- Peter Bigler
- Departement für Chemie und Biochemie, Universität Bern, Bern, Switzerland
| | - Julien Furrer
- Departement für Chemie und Biochemie, Universität Bern, Bern, Switzerland
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Studer V, Anghel N, Desiatkina O, Felder T, Boubaker G, Amdouni Y, Ramseier J, Hungerbühler M, Kempf C, Heverhagen JT, Hemphill A, Ruprecht N, Furrer J, Păunescu E. Conjugates Containing Two and Three Trithiolato-Bridged Dinuclear Ruthenium(II)-Arene Units as In Vitro Antiparasitic and Anticancer Agents. Pharmaceuticals (Basel) 2020; 13:E471. [PMID: 33339451 PMCID: PMC7767221 DOI: 10.3390/ph13120471] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 12/10/2020] [Accepted: 12/11/2020] [Indexed: 12/15/2022] Open
Abstract
The synthesis, characterization, and in vitro antiparasitic and anticancer activity evaluation of new conjugates containing two and three dinuclear trithiolato-bridged ruthenium(II)-arene units are presented. Antiparasitic activity was evaluated using transgenic Toxoplasmagondii tachyzoites constitutively expressing β-galactosidase grown in human foreskin fibroblasts (HFF). The compounds inhibited T.gondii proliferation with IC50 values ranging from 90 to 539 nM, and seven derivatives displayed IC50 values lower than the reference compound pyrimethamine, which is currently used for treatment of toxoplasmosis. Overall, compound flexibility and size impacted on the anti-Toxoplasma activity. The anticancer activity of 14 compounds was assessed against cancer cell lines A2780, A2780cisR (human ovarian cisplatin sensitive and resistant), A24, (D-)A24cisPt8.0 (human lung adenocarcinoma cells wild type and cisPt resistant subline). The compounds displayed IC50 values ranging from 23 to 650 nM. In A2780cisR, A24 and (D-)A24cisPt8.0 cells, all compounds were considerably more cytotoxic than cisplatin, with IC50 values lower by two orders of magnitude. Irrespective of the nature of the connectors (alkyl/aryl) or the numbers of the di-ruthenium units (two/three), ester conjugates 6-10 and 20 exhibited similar antiproliferative profiles, and were more cytotoxic than amide analogues 11-14, 23, and 24. Polynuclear conjugates with multiple trithiolato-bridged di-ruthenium(II)-arene moieties deserve further investigation.
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Affiliation(s)
- Valentin Studer
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland; (V.S.); (O.D.); (T.F.)
| | - Nicoleta Anghel
- Vetsuisse Faculty, Institute of Parasitology, University of Bern, Länggassstrasse 122, CH-3012 Bern, Switzerland; (N.A.); (G.B.); (Y.A.); (J.R.)
| | - Oksana Desiatkina
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland; (V.S.); (O.D.); (T.F.)
| | - Timo Felder
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland; (V.S.); (O.D.); (T.F.)
| | - Ghalia Boubaker
- Vetsuisse Faculty, Institute of Parasitology, University of Bern, Länggassstrasse 122, CH-3012 Bern, Switzerland; (N.A.); (G.B.); (Y.A.); (J.R.)
| | - Yosra Amdouni
- Vetsuisse Faculty, Institute of Parasitology, University of Bern, Länggassstrasse 122, CH-3012 Bern, Switzerland; (N.A.); (G.B.); (Y.A.); (J.R.)
- Laboratoire de Parasitologie, Institution de la Recherche et de l’Enseignement Supérieur Agricoles, École Nationale de Médecine Vétérinaire de Sidi Thabet, University of Manouba, Sidi Thabet 2020, Tunisia
| | - Jessica Ramseier
- Vetsuisse Faculty, Institute of Parasitology, University of Bern, Länggassstrasse 122, CH-3012 Bern, Switzerland; (N.A.); (G.B.); (Y.A.); (J.R.)
| | - Martin Hungerbühler
- Department of BioMedical Research, Experimental Radiology, University of Bern, CH-3008 Bern, Switzerland; (M.H.); (C.K.); (J.T.H.)
- Department of Diagnostic, Interventional and Pediatric Radiology, Bern University Hospital, University of Bern, CH-3010 Bern, Switzerland
| | - Christoph Kempf
- Department of BioMedical Research, Experimental Radiology, University of Bern, CH-3008 Bern, Switzerland; (M.H.); (C.K.); (J.T.H.)
- Department of Diagnostic, Interventional and Pediatric Radiology, Bern University Hospital, University of Bern, CH-3010 Bern, Switzerland
| | - Johannes Thomas Heverhagen
- Department of BioMedical Research, Experimental Radiology, University of Bern, CH-3008 Bern, Switzerland; (M.H.); (C.K.); (J.T.H.)
- Department of Diagnostic, Interventional and Pediatric Radiology, Bern University Hospital, University of Bern, CH-3010 Bern, Switzerland
| | - Andrew Hemphill
- Vetsuisse Faculty, Institute of Parasitology, University of Bern, Länggassstrasse 122, CH-3012 Bern, Switzerland; (N.A.); (G.B.); (Y.A.); (J.R.)
| | - Nico Ruprecht
- Department of BioMedical Research, Experimental Radiology, University of Bern, CH-3008 Bern, Switzerland; (M.H.); (C.K.); (J.T.H.)
- Department of Diagnostic, Interventional and Pediatric Radiology, Bern University Hospital, University of Bern, CH-3010 Bern, Switzerland
| | - Julien Furrer
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland; (V.S.); (O.D.); (T.F.)
| | - Emilia Păunescu
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland; (V.S.); (O.D.); (T.F.)
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16
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Primasová H, Vermathen M, Furrer J. Interactions of Cationic Diruthenium Trithiolato Complexes with Phospholipid Membranes Studied by NMR Spectroscopy. J Phys Chem B 2020; 124:8822-8834. [PMID: 32930600 DOI: 10.1021/acs.jpcb.0c05133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
To apprehend the possible mechanisms involved in the cellular uptake and the membrane interactions of cytotoxic dinuclear p-cymene trithiolato ruthenium(II) complexes, the interactions of the complexes [(η6-p-MeC6H4Pri)2Ru2(R1)2(R2)]+ (R1 = R2 = SC6H4-m-Pri:1; R1 = SC6H4-p-OMe, R2 = SC6H4-p-OH:2; R1 = SCH2C6H4-p-OMe, R2 = SC6H4-p-OH:3) with 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) vesicles and 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC) micelles were studied using nuclear magnetic resonance (NMR) spectroscopy. 1H NMR, nuclear Overhauser effect (NOE), diffusion ordered spectroscopy (DOSY), and T1 and T2 relaxation data provided information on interactions between the complexes and the model membranes and on the submolecular localization of the complexes at the membrane interface. The results suggest that (a) the interaction takes place without new covalent adduct formation, (b) the cationic diruthenium complexes interact with DOPC head groups most likely involving electrostatic interactions while remaining structurally unchanged, (c) the changes indicating interactions are more pronounced for the most lipophilic complex 1, and (d) the diruthenium complexes remain at the exterior vesicle surface and are unlikely inserted between the phospholipid chains. The complexes also interact with micellar/free DHPC and seem to induce micellization or aggregation in solutions below critical micelle concentration (CMC). Our study suggests high affinity of the Ru complexes for the membrane surface that likely plays a key role in cellular uptake and possibly also in redistribution in mitochondria.
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Affiliation(s)
- Hedvika Primasová
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
| | - Martina Vermathen
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
| | - Julien Furrer
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
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Desiatkina O, Păunescu E, Mösching M, Anghel N, Boubaker G, Amdouni Y, Hemphill A, Furrer J. Coumarin-Tagged Dinuclear Trithiolato-Bridged Ruthenium(II)⋅Arene Complexes: Photophysical Properties and Antiparasitic Activity. Chembiochem 2020; 21:2818-2835. [PMID: 32347622 PMCID: PMC7586963 DOI: 10.1002/cbic.202000174] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [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: 03/18/2020] [Revised: 04/28/2020] [Indexed: 11/06/2022]
Abstract
The synthesis, characterization, photophysical and biological properties of 13 new conjugate coumarin-diruthenium(II)⋅arene complexes against Toxoplasma gondii are presented. For all conjugate organometallic unit/coumarins, an almost complete loss of fluorescence efficacy was observed. However, the nature of the fluorophore, the type of bonding, the presence and length of a linker between the coumarin dye and the ruthenium(II) moiety, and the number of dye units influenced their biological properties. The in vitro activity against a transgenic T. gondii strain grown in human foreskin fibroblasts (HFF) leads to IC50 values for T. gondii β-gal from 105 to 735 nM. Of note is that nine compounds displayed lower IC50 than the standard drug pyrimethamine. One compound applied at its IC50 did not affect B-cell proliferation but had an impact on T-cell proliferation in murine splenocyte cultures. Transmission electron microscopy of T. gondii β-gal-infected HFF showed that treatment predominantly affected the parasites' mitochondrion.
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Affiliation(s)
- Oksana Desiatkina
- Department of Chemistry and BiochemistryUniversity of BernFreiestrasse 33012BernSwitzerland
| | - Emilia Păunescu
- Department of Chemistry and BiochemistryUniversity of BernFreiestrasse 33012BernSwitzerland
| | - Martin Mösching
- Department of Chemistry and BiochemistryUniversity of BernFreiestrasse 33012BernSwitzerland
| | - Nicoleta Anghel
- Institute of Parasitology Vetsuisse FacultyUniversity of BernLänggass-Strasse 1223012BernSwitzerland
| | - Ghalia Boubaker
- Institute of Parasitology Vetsuisse FacultyUniversity of BernLänggass-Strasse 1223012BernSwitzerland
| | - Yosra Amdouni
- Institute of Parasitology Vetsuisse FacultyUniversity of BernLänggass-Strasse 1223012BernSwitzerland
| | - Andrew Hemphill
- Institute of Parasitology Vetsuisse FacultyUniversity of BernLänggass-Strasse 1223012BernSwitzerland
| | - Julien Furrer
- Department of Chemistry and BiochemistryUniversity of BernFreiestrasse 33012BernSwitzerland
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Eldridge H, DeDonno M, Furrer J, Champod C. Examining and expanding the friction ridge value decision. Forensic Sci Int 2020; 314:110408. [DOI: 10.1016/j.forsciint.2020.110408] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 05/29/2020] [Accepted: 07/03/2020] [Indexed: 11/25/2022]
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Basto AP, Anghel N, Rubbiani R, Müller J, Stibal D, Giannini F, Süss-Fink G, Balmer V, Gasser G, Furrer J, Hemphill A. Targeting of the mitochondrion by dinuclear thiolato-bridged arene ruthenium complexes in cancer cells and in the apicomplexan parasite Neospora caninum. Metallomics 2020; 11:462-474. [PMID: 30620038 DOI: 10.1039/c8mt00307f] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A library of 18 dinuclear-thiolato bridged arene ruthenium complexes, some of which with demonstrated activity against cancer cells, was screened for activity against a transgenic Neospora caninum strain that constitutively expresses beta-galactosidase. Initial assessments were done at concentrations of 2500, 250, 25 and 2.5 nM, and 5 compounds were further evaluated with regard to their half maximal proliferation-inhibiting concentration (IC50). Among those, [(η6-p-MeC6H4Pri)2Ru2(μ2-SC6H4-p-CH3)3]Cl (1), [(η6-p-MeC6H4Pri)2Ru2(μ2-SC6H4-p-But)3]Cl (2) and [(η6-p-MeC6H4Pri)2Ru2(μ2-SCH2C6H4-p-But)2(μ2-SC6H4-p-OH)]BF4 (9) inhibited N. caninum proliferation with low C50 values of 15, 5 and 1 nM, respectively, while [(η6-p-MeC6H4Pri)2Ru2(μ2-SC6H4-p-OH)3]Cl (3) and [(η6-p-MeC6H4Pri)2Ru2(μ2-SC6H4-p-mco)3]Cl (5, mco = 4-methylcoumarinyl) were less active (IC50 = 280 and 108 nM, respectively). These compounds did not affect human foreskin fibroblast (HFF) host cells at dosages of 5 μM and above, but impaired proliferation of the human ovarian carcinoma cell line A2780 (IC50 values of 130 nM (1), 30 nM (2), 530 nM (3), 7730 nM (5), 130 nM (9)). A2780 cancer cells were treated with complexes 1, 2, and 5, and biodistribution analysis using inductively coupled plasma mass spectrometry (ICP-MS) showed that most of the drugs accumulated in the mitochondrial fractions. Transmission electron microscopy showed that the parasite mitochondrion is the primary target also in N. caninum tachyzoites, but these compounds, when applied at 200 nM for 15 days in vitro, did not act parasiticidal. Complexes 1, 2 and 9 applied orally at 2 and 10 mg kg-1 day-1 during 5 days in a neosporosis mouse model did not reduce parasite load and did not limit parasite dissemination to the central nervous system. In accordance with these results, ICP-MS carried out on different organs of mice orally administrated with complexes 1 and 9, demonstrated that the drugs were readily absorbed, and after 3 and 48 h, were mainly detected in liver and kidney, but were largely absent from the brain. Thus, dinuclear thiolato-bridged arene ruthenium complexes exhibit interesting activities against N. caninum in vitro, but further modifications of these promising molecules are required to improve their bioavailability and pharmacokinetic properties in order to exert a pronounced and selective effect against N. caninum in vivo.
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Affiliation(s)
- Afonso P Basto
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Länggassstrasse 122, CH-3012 Berne, Switzerland.
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Pfister S, Sauser L, Gjuroski I, Furrer J, Vermathen M. Monitoring the encapsulation of chlorin e6 derivatives into polymer carriers by NMR spectroscopy. J PORPHYR PHTHALOCYA 2020. [DOI: 10.1142/s1088424619501815] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The encapsulation of five derivatives of chlorin e6 with different hydrophobicity and aggregation properties into a series of five poloxamer-type triblock copolymer micelles (BCMs) with varying numbers of polyethylene and polypropylene glycol (PEG, PPG) units was monitored using 1H NMR spectroscopy. NMR chemical shift and line shape analysis, as well as dynamic methods including diffusion ordered spectroscopy (DOSY) and T1 and T2 relaxation time measurements of the chlorin and the polymer resonances, proved useful to assess the chlorin–BCM compatibility. The poloxamers had high capability to break up aggregates formed by chlorins up to intermediate hydrophobicity. Physically entrapped chlorins were always localized in the BCM core region. The loading capacity correlated with chlorin polarity for all poloxamers among which those with the lowest number of PPG units were most efficient. DOSY data revealed that relatively weakly aggregating chlorins partition between the aqueous bulk and micellar environment whereas more hydrophobic chlorins are well retained in the BCM core region, rendering these systems more stable. T1 and T2 relaxation time measurements indicated that motional freedom in the BCM core region contributes to encapsulation efficiency. The BCM corona dynamics were rather insensitive towards chlorin entrapment except for the poloxamers with short PEG chains. The presented data demonstrate that 1H NMR spectroscopy is a powerful complementary tool for probing the compatibility of porphyrinic compounds with polymeric carriers such as poloxamer BCMs, which is a prerequisite in the development of stable and highly efficient drug delivery systems suitable for medical applications like photodynamic therapy of tumors.
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Affiliation(s)
- Sara Pfister
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012 Bern, Switzerland
| | - Luca Sauser
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012 Bern, Switzerland
| | - Ilche Gjuroski
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012 Bern, Switzerland
| | - Julien Furrer
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012 Bern, Switzerland
| | - Martina Vermathen
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012 Bern, Switzerland
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21
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Primasová H, Ninova S, de Capitani M, Daepp J, Aschauer U, Furrer J. Dinuclear thiolato-bridged arene ruthenium complexes: from reaction conditions and mechanism to synthesis of new complexes. RSC Adv 2020; 10:40106-40116. [PMID: 35520857 PMCID: PMC9057517 DOI: 10.1039/d0ra08146a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 10/21/2020] [Indexed: 11/27/2022] Open
Abstract
Several dinuclear thiophenolato-bridged arene ruthenium complexes [(η6-p-MeC6H4Pri)2Ru2(μ2-SC6H4-R)3]+ (R = H, NO2, F) could so far only be obtained in fair yields using the synthetic route established in the early 2000s. With much less reactive aliphatic thiols or with bulky thiols, the reactions become even less efficient and the desired complexes are obtained with low yields or not at all. We employed density functional theory (DFT) calculations to gain a fundamental understanding of the reaction mechanisms leading to the formation of dithiolato and trithiolato complexes starting from the dichloro(p-cymene)ruthenium(ii) dimer [(η6-p-MeC6H4Pri)Ru(μ2-Cl)Cl]2. The results of the DFT study enabled us to rationalise the experimental results and allowed us, via a modified synthetic route, to synthesise previously unreported and hitherto considered as unrealistic complexes. Our study opens up possibilities for the synthesis of so far inaccessible thiolato-bridged dinuclear arene ruthenium(ii) complexes but more generally, also the synthesis of other thiolato-bridged dinuclear group 8 and 9 metal complexes could be reexamined. We used DFT calculations to understand the reaction mechanisms leading to the formation of dinuclear thiophenolato-bridged arene ruthenium complexes. DFT prompted us to modify the usual synthetic route, which enabled the synthesis of new complexes.![]()
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Affiliation(s)
| | - Silviya Ninova
- Department of Chemistry and Biochemistry
- Universität Bern
- Switzerland
| | | | - Jana Daepp
- Department of Chemistry and Biochemistry
- Universität Bern
- Switzerland
| | - Ulrich Aschauer
- Department of Chemistry and Biochemistry
- Universität Bern
- Switzerland
| | - Julien Furrer
- Department of Chemistry and Biochemistry
- Universität Bern
- Switzerland
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22
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Gjuroski I, Girousi E, Meyer C, Hertig D, Stojkov D, Fux M, Schnidrig N, Bucher J, Pfister S, Sauser L, Simon HU, Vermathen P, Furrer J, Vermathen M. Evaluation of polyvinylpyrrolidone and block copolymer micelle encapsulation of serine chlorin e6 and chlorin e4 on their reactivity towards albumin and transferrin and their cell uptake. J Control Release 2019; 316:150-167. [PMID: 31689463 DOI: 10.1016/j.jconrel.2019.10.010] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 09/02/2019] [Accepted: 10/02/2019] [Indexed: 01/10/2023]
Abstract
Encapsulation of porphyrinic photosensitizers (PSs) into polymeric carriers plays an important role in enhancing their efficiency as drugs in photodynamic therapy (PDT). Porphyrin aggregation and low solubility as well as the preservation of the advantageous photophysical properties pose a challenge on the design of efficient PS-carrier systems. Block copolymer micelles (BCMs) and polyvinylpyrrolidone (PVP) are promising drug delivery vehicles for physical entrapment of PSs. BCMs exhibit enhanced dynamics as compared to the less flexible PVP network. In the current work the question is addressed how these different dynamics affect PS encapsulation, release from the carrier, reaction with serum proteins, and cellular uptake. The porphyrinic compounds serine-amide of chlorin e6 (SerCE) and chlorin e4 (CE4) were used as model PSs with different lipophilicity and aggregation properties. 1H NMR and fluorescence spectroscopy were applied to study their interactions with PVP and BCMs consisting of Kolliphor P188 (KP). Both chlorins were well encapsulated by the carriers and had improved photophysical properties. Compared to SerCE, the more lipophilic CE4 exhibited stronger hydrophobic interactions with the BCM core, stabilizing the system and preventing exchange with the surrounding medium as was shown by NMR NOESY and DOSY experiments. PVP and BCMs protected the encapsulated chlorins against interaction with human transferrin (Tf). However, SerCE and CE4 were released from BCMs in favor of binding to human serum albumin (HSA) while PVP prevented interaction with HSA. Fluorescence spectroscopic studies revealed that HSA binds to the surface of PVP forming a protein corona. PVP and BCMs reduced cellular uptake of the chlorins. However, encapsulation into BCMs resulted in more efficient cell internalization for CE4 than for SerCE. HSA significantly lowered both, free and carrier-mediated cell uptake for CE4 and SerCE. In conclusion, PVP appears as the more universal delivery system covering a broad range of host molecules with respect to polarity, whereas BCMs require a higher drug-carrier compatibility. Poorly soluble hydrophobic PSs benefit stronger from BCM-type carriers due to enhanced bioavailability through disaggregation and solubilization allowing for more efficient cell uptake. In addition, increased PS-carrier hydrophobic interactions have a stabilizing effect. For more hydrophilic PSs, the main advantage of polymeric carriers like PVP or poloxamer micelles lies in their protection during the transport through the bloodstream. HSA binding plays an important role for drug release and cell uptake in carrier-mediated delivery to the target tissue.
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Affiliation(s)
- Ilche Gjuroski
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland.
| | - Eleftheria Girousi
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Christoph Meyer
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Damian Hertig
- Department of BioMedical Research and Radiology, University of Bern and Inselspital, sitem-insel AG, Freiburgstrasse 3, CH-3010, Bern, Switzerland; Institute of Clinical Chemistry, University of Bern and Inselspital, CH-3010, Bern, Switzerland
| | - Darko Stojkov
- Institute of Pharmacology, University of Bern and Inselspital, CH-3010, Bern, Switzerland
| | - Michaela Fux
- Institute of Clinical Chemistry, University of Bern and Inselspital, CH-3010, Bern, Switzerland
| | - Nicolas Schnidrig
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Jan Bucher
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Sara Pfister
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Luca Sauser
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern and Inselspital, CH-3010, Bern, Switzerland
| | - Peter Vermathen
- Department of BioMedical Research and Radiology, University of Bern and Inselspital, sitem-insel AG, Freiburgstrasse 3, CH-3010, Bern, Switzerland
| | - Julien Furrer
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Martina Vermathen
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland.
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23
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Troxler LJ, Werren JP, Schaffner TO, Mostacci N, Vermathen P, Vermathen M, Wüthrich D, Simillion C, Brugger SD, Bruggmann R, Hathaway LJ, Furrer J, Hilty M. Carbon source regulates polysaccharide capsule biosynthesis in Streptococcus pneumoniae. J Biol Chem 2019; 294:17224-17238. [PMID: 31594867 PMCID: PMC6873171 DOI: 10.1074/jbc.ra119.010764] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 10/02/2019] [Indexed: 11/06/2022] Open
Abstract
The exopolysaccharide capsule of Streptococcus pneumoniae is an important virulence factor, but the mechanisms that regulate capsule thickness are not fully understood. Here, we investigated the effects of various exogenously supplied carbohydrates on capsule production and gene expression in several pneumococcal serotypes. Microscopy analyses indicated a near absence of the capsular polysaccharide (CPS) when S. pneumoniae was grown on fructose. Moreover, serotype 7F pneumococci produced much less CPS than strains of other serotypes (6B, 6C, 9V, 15, and 23F) when grown on glucose or sucrose. RNA-sequencing revealed carbon source-dependent regulation of distinct genes of WT strains and capsule-switch mutants of serotypes 6B and 7F, but could not explain the mechanism of capsule thickness regulation. In contrast, 31P NMR of whole-cell extract from capsule-knockout strains (Δcps) clearly revealed the accumulation or absence of capsule precursor metabolites when cells were grown on glucose or fructose, respectively. This finding suggests that fructose uptake mainly results in intracellular fructose 1-phosphate, which is not converted to CPS precursors. In addition, serotype 7F strains accumulated more precursors than did 6B strains, indicating less efficient conversion of precursor metabolites into the CPS in 7F, in line with its thinner capsule. Finally, isotopologue sucrose labeling and NMR analyses revealed that the uptake of the labeled fructose subunit into the capsule is <10% that of glucose. Our findings on the effects of carbon sources on CPS production in different S. pneumoniae serotypes may contribute to a better understanding of pneumococcal diseases and could inform future therapeutic approaches.
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Affiliation(s)
- Lukas J Troxler
- Institute for Infectious Diseases, Faculty of Medicine, University of Bern, 3001 Bern, Switzerland.,Graduate School for Cellular and Biomedical Sciences, University of Bern, 3012 Bern, Switzerland
| | - Joel P Werren
- Institute for Infectious Diseases, Faculty of Medicine, University of Bern, 3001 Bern, Switzerland.,Graduate School for Cellular and Biomedical Sciences, University of Bern, 3012 Bern, Switzerland
| | - Thierry O Schaffner
- Institute for Infectious Diseases, Faculty of Medicine, University of Bern, 3001 Bern, Switzerland
| | - Nadezda Mostacci
- Institute for Infectious Diseases, Faculty of Medicine, University of Bern, 3001 Bern, Switzerland
| | - Peter Vermathen
- Department of BioMedical Research and Radiology, University of Bern and Inselspital, 3012 Bern, Switzerland
| | - Martina Vermathen
- Department of Chemistry and Biochemistry, University of Bern, 3012 Bern, Switzerland
| | - Daniel Wüthrich
- Interfaculty Bioinformatics Unit and Swiss Institute of Bioinformatics, University of Bern, 3012 Bern, Switzerland.,Applied Microbiology Research Unit, Department of Biomedicine, University of Basel, 4031 Basel, Switzerland.,Division of Clinical Microbiology, University Hospital Basel, 4031 Basel, Switzerland
| | - Cedric Simillion
- Interfaculty Bioinformatics Unit and Swiss Institute of Bioinformatics, University of Bern, 3012 Bern, Switzerland
| | - Silvio D Brugger
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland.,The Forsyth Institute (Microbiology), Cambridge, Massachusetts 02142.,Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, Massachusetts 02142
| | - Rémy Bruggmann
- Interfaculty Bioinformatics Unit and Swiss Institute of Bioinformatics, University of Bern, 3012 Bern, Switzerland
| | - Lucy J Hathaway
- Institute for Infectious Diseases, Faculty of Medicine, University of Bern, 3001 Bern, Switzerland
| | - Julien Furrer
- Department of Chemistry and Biochemistry, University of Bern, 3012 Bern, Switzerland
| | - Markus Hilty
- Institute for Infectious Diseases, Faculty of Medicine, University of Bern, 3001 Bern, Switzerland
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24
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Jelk J, Balmer V, Stibal D, Giannini F, Süss-Fink G, Bütikofer P, Furrer J, Hemphill A. Anti-parasitic dinuclear thiolato-bridged arene ruthenium complexes alter the mitochondrial ultrastructure and membrane potential in Trypanosoma brucei bloodstream forms. Exp Parasitol 2019; 205:107753. [DOI: 10.1016/j.exppara.2019.107753] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 08/20/2019] [Accepted: 08/25/2019] [Indexed: 01/28/2023]
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25
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Bodappa N, Fu YC, Broekmann P, Furrer J, Zick K, Vesztergom S, Tahara H, Sagara T. Electron transfer controlled by solvent and counter-anion dynamics in electrochemistry of viologen-type ionic liquid. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2019.134559] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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26
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Rudnev AV, Kiran K, Cedeño López A, Dutta A, Gjuroski I, Furrer J, Broekmann P. Enhanced electrocatalytic CO formation from CO2 on nanostructured silver foam electrodes in ionic liquid/water mixtures. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2019.03.102] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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27
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Petruk G, Monti DM, Ferraro G, Pica A, D'Elia L, Pane F, Amoresano A, Furrer J, Kowalski K, Merlino A. Encapsulation of the Dinuclear Trithiolato-Bridged Arene Ruthenium Complex Diruthenium-1 in an Apoferritin Nanocage: Structure and Cytotoxicity. ChemMedChem 2019; 14:594-602. [PMID: 30674089 DOI: 10.1002/cmdc.201800805] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 01/21/2019] [Indexed: 12/14/2022]
Abstract
The effects of encapsulating the cytotoxic dinuclear trithiolato-bridged arene ruthenium complex [(η6 -p-MeC6 H4 iPr)2 Ru2 (μ2 -S-p-C6 H4 tBu)3 ]Cl (DiRu-1) within the apoferritin (AFt) nanocage were investigated. The DiRu-1-AFt nanocarrier was characterized by UV/Vis spectroscopy, ICP-MS, CD and X-ray crystallography. In contrast to previously reported Au- and Pt-based drug-loaded AFt carriers, we found no evidence of direct interactions between DiRu-1 and AFt. DiRu-1-AFt is cytotoxic toward immortalized murine BALB/c-3T3 fibroblasts transformed with SV40 virus (SVT2) and human epidermoid carcinoma A431 malignant cells, and exhibits moderate selectivity for these cancer cells over normal BALB/c-3T3 cells. DiRu-1-AFt triggers the production of reactive oxygen species, depolarization of mitochondrial membrane potential, and induces cell death via p53-mediated apoptosis. Comparison between our data and previous results suggests that the presence of specific interactions between a metal-based drug and AFt within the protein cage is not essential for drug encapsulation.
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Affiliation(s)
- Ganna Petruk
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario di Monte Sant'Angelo, via Cinthia 21, 80126, Naples, Italy
| | - Daria Maria Monti
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario di Monte Sant'Angelo, via Cinthia 21, 80126, Naples, Italy
| | - Giarita Ferraro
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario di Monte Sant'Angelo, via Cinthia 21, 80126, Naples, Italy
| | - Andrea Pica
- EMBL, CS 90181, 71 AV des Martyrs, 38009, Grenoble (38), France
| | - Luigi D'Elia
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario di Monte Sant'Angelo, via Cinthia 21, 80126, Naples, Italy
| | - Francesca Pane
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario di Monte Sant'Angelo, via Cinthia 21, 80126, Naples, Italy
| | - Angela Amoresano
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario di Monte Sant'Angelo, via Cinthia 21, 80126, Naples, Italy
| | - Julien Furrer
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Konrad Kowalski
- Department of Organic Chemistry, Faculty of Chemistry, University of Łódź, Tamka 12, 91-403, Poland
| | - Antonello Merlino
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario di Monte Sant'Angelo, via Cinthia 21, 80126, Naples, Italy
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28
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Bigler P, Furrer J. D-HMBC versus LR-HSQMBC: Which experiment provides theoretically and experimentally the best results? Magn Reson Chem 2018; 57:129-143. [PMID: 30499122 DOI: 10.1002/mrc.4810] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 11/21/2018] [Accepted: 11/21/2018] [Indexed: 06/09/2023]
Abstract
The long-range heteronuclear single quantum multiple bond correlation (LR-HSQMBC) experiment is the experiment of choice for visualizing heteronuclear long-range coupling interactions n JCH across 4-6-bonds and is experimentally superior to the decoupled heteronuclear multiple-bond correlation (D-HMBC) experiment. Yet, the exact reasons have not been fully understood and established. On the basis of our recent investigation of the nonrefocused variants LR-HSQC and HMBC, we have extended a JHH' -dedicated investigation to the D-HMBC and LR-HSQMBC experiments. Unlike the nonrefocused variants, the influence of homonuclear couplings JHH' on the intensity of long-range n JCH cross-peaks is not easily predictable and may be summarized as follows: (a) irrespective of the magnitude and number of JHH' interactions long-range n JCH cross-peaks are more intense in D-HMBC spectra as long as the evolution delay Δ is not too large, because in contrast to LR-HSQMBC no JHH' -caused intensity zeroes will occur. (b) If JHH' is small and Δ large, the intensity of cross peaks in D-HMBC spectra may be weakened or may even vanish at Δ = (0.25+0.5k)/JHH ', whereas for the LR-HSQMBC this unwanted effect occurs at Δ = k + 0.5/JHH' . Consequently, when Δ is adjusted to visualize weak n JCH long-range correlations, our findings corroborate that there are potentially more cross-peaks expected to show up in a LR-HSQMBC spectrum compared with a D-HMBC spectrum. This has been indeed noticed experimentally, even though the intensity of a many long-range n JCH cross-peaks may still be higher in the spectra of the D-HMBC experiment correspondingly adjusted for detecting weak n JCH correlations.
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Affiliation(s)
- Peter Bigler
- Departement für Chemie und Biochemie, Universität Bern, Bern, Switzerland
| | - Julien Furrer
- Departement für Chemie und Biochemie, Universität Bern, Bern, Switzerland
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29
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Bigler P, Furrer J. Why is HMBC superior to LR-HSQC? Influence of homonuclear couplings J HH' on the intensity of long-range correlations. Magn Reson Chem 2018; 56:1101-1116. [PMID: 29907970 DOI: 10.1002/mrc.4762] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 05/16/2018] [Accepted: 06/05/2018] [Indexed: 06/08/2023]
Abstract
Long-range heteronuclear single quantum correlation (LR-HSQC) experiments may be applied as an alternative to heteronuclear multiple-bond correlation (HMBC) experiments for detecting long-range correlations but has never enjoyed popularity for that purpose. To the best of our knowledge, the exact reasons have not yet been fully established. For both experiments, it is widely accepted that the evolution of proton-proton homonuclear couplings JHH' during the polarization transfer delays Δ leads to significant losses, and that the intensity of the observable coherence is zero when JHH' matches the condition Δ = 0.5/JHH' . Here, we analyze the influence of JHH' on the intensity of long-range correlations in HMBC and LR-HSQC spectra. We show that for both experiments long-range correlations will not be canceled because of homonuclear couplings JHH' . Our theoretical and experimental results definitely establish and validate the superiority of HMBC-based experiments among the family of heteronuclear long-range correlation experiments: (a) the overall cross peak's intensity is higher, and (b) in LR-HSQC experiments, the intensity of the long-range cross peaks is additionally influenced in an unwanted way by the magnitude and number of passive homonuclear proton-proton couplings JHH' .
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Affiliation(s)
- Peter Bigler
- Departement für Chemie und Biochemie, Universität Bern, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Julien Furrer
- Departement für Chemie und Biochemie, Universität Bern, Freiestrasse 3, CH-3012, Bern, Switzerland
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30
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Bigler P, Furrer J. Measurement of long-range heteronuclear coupling constants using the peak intensity in classical 1D HMBC spectra. Magn Reson Chem 2018; 56:329-337. [PMID: 29336081 DOI: 10.1002/mrc.4713] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 01/04/2018] [Accepted: 01/05/2018] [Indexed: 06/07/2023]
Abstract
In this contribution, we show that the magnitude of heteronuclear long-range coupling constants can be directly extracted from the classical 1D HMBC spectra, as all multiplet lines of a cross-peak always and exclusively vanish for the condition Δ = k/n JCH . To the best of our knowledge, this feature of the classical HMBC has not yet been noticed and exploited. This condition holds true, irrespective of the magnitude and numbers of additional active and passive homonuclear n JHH' couplings. Alternatively, the n JCH value may also be evaluated by fitting the peak's intensity in the individual spectra to its simple sin(πn JCH Δ)exp(-Δ/T2eff ) dependence. Compared to the previously proposed J-HMBC sequences that also use the variation of the cross-peak's intensity for extracting the coupling constants, the classical HMBC pulse sequence is significantly more sensitive.
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Affiliation(s)
- Peter Bigler
- Departement für Chemie und Biochemie, Universität Bern, Freiestrasse 3, Berne, CH-3012, Switzerland
| | - Julien Furrer
- Departement für Chemie und Biochemie, Universität Bern, Freiestrasse 3, Berne, CH-3012, Switzerland
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31
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Gjuroski I, Furrer J, Vermathen M. How Does the Encapsulation of Porphyrinic Photosensitizers into Polymer Matrices Affect Their Self-Association and Dynamic Properties? Chemphyschem 2018; 19:1089-1102. [PMID: 29384257 DOI: 10.1002/cphc.201701318] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 01/26/2018] [Indexed: 12/20/2022]
Abstract
Photodynamic therapy (PDT) with porphyrinic photosensitizers largely relies on efficient drug formulations to prevent porphyrin aggregation and to enhance water solubility and stability in physiologic environments. In this study, we compare two polymeric carrier systems, polyvinylpyrrolidone (PVP) and block copolymer micelles (BCMs) formed by the poloxamer Kolliphor P188 (KP), for their encapsulation efficiencies of porphyrin (xPP) and chlorin e6 (xCE) derivatives. Monomerization, loading efficiency, and dynamic properties were examined by 1 H NMR spectroscopy chemical shift titration, DOSY, and T2 relaxation time measurements. Binding affinity was determined by UV/Vis spectroscopy. Both PVP and KP-BCMs were well suited to disaggregate and encapsulate amphiphilic xCE, whereas they were less efficient for the xPP compounds. PVP exhibited higher monomerization efficiency than KP-BCMs. Significant differences were found in the dynamic behavior of the carriers. PVP formed rather stable complexes with the porphyrinic compounds, whereas a dynamic equilibrium between free and bound porphyrins was found to exist in the presence of KP-BCMs. This may have a considerable impact on the pharmacokinetic properties of the corresponding delivery systems.
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Affiliation(s)
- Ilche Gjuroski
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Julien Furrer
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Martina Vermathen
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
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32
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Paul LE, Therrien B, Furrer J. The complex-in-a-complex cation [Pt(acac)2⊂(p-cym)6Ru6(tpt)2(dhnq)3]6+: Its stability towards biological ligands. Inorganica Chim Acta 2018. [DOI: 10.1016/j.ica.2017.08.045] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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33
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Rudnev AV, Fu YC, Gjuroski I, Stricker F, Furrer J, Kovács N, Vesztergom S, Broekmann P. Cover Feature: Transport Matters: Boosting CO 2
Electroreduction in Mixtures of [BMIm][BF 4
]/Water by Enhanced Diffusion (ChemPhysChem 22/2017). Chemphyschem 2017. [DOI: 10.1002/cphc.201701164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Alexander V. Rudnev
- Department of Chemistry and Biochemistry; University of Bern; Freiestrasse 3 3012 Bern Switzerland
- A. N. Frumkin Institute of Physical Chemistry and Electrochemistry; Russian Academy of Sciences; Leninskii prospekt 31 119991 Moscow Russia
| | - Yong-Chun Fu
- Department of Chemistry and Biochemistry; University of Bern; Freiestrasse 3 3012 Bern Switzerland
| | - Ilche Gjuroski
- Department of Chemistry and Biochemistry; University of Bern; Freiestrasse 3 3012 Bern Switzerland
| | - Florian Stricker
- Department of Chemistry and Biochemistry; University of Bern; Freiestrasse 3 3012 Bern Switzerland
| | - Julien Furrer
- Department of Chemistry and Biochemistry; University of Bern; Freiestrasse 3 3012 Bern Switzerland
| | - Noémi Kovács
- Department of Physical Chemistry; Eötvös Loránd University; Pázmány Péter sétány 1/A 1117 Budapest Hungary
| | - Soma Vesztergom
- Department of Physical Chemistry; Eötvös Loránd University; Pázmány Péter sétány 1/A 1117 Budapest Hungary
| | - Peter Broekmann
- Department of Chemistry and Biochemistry; University of Bern; Freiestrasse 3 3012 Bern Switzerland
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34
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Rudnev AV, Fu YC, Gjuroski I, Stricker F, Furrer J, Kovács N, Vesztergom S, Broekmann P. Transport Matters: Boosting CO 2 Electroreduction in Mixtures of [BMIm][BF 4 ]/Water by Enhanced Diffusion. Chemphyschem 2017; 18:3153-3162. [PMID: 28872751 DOI: 10.1002/cphc.201700737] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Revised: 08/02/2017] [Indexed: 12/21/2022]
Abstract
Room-temperature ionic liquids (RTILs) are promising new electrolytes for efficient carbon dioxide reduction. However, due to their high viscosity, the mass transport of CO2 in RTILs is typically slow, at least one order of magnitude slower than in aqueous systems. One possibility to improve mass transport in RTILs is to decrease their viscosity through dilution with water. Herein, defined amounts of water are added to 1-butyl-3methylimidazolium tetrafluoroborate ([BMIm][BF4 ]), which is a hydrophilic RTIL. Electrochemical measurements on quiescent and hydrodynamic systems both indicate enhanced CO2 electroreduction. This enhancement has its origin in thermodynamic/kinetic effects (the addition of water increases the availability of H+ , which is a reaction partner of CO2 electroreduction) and in an increased rate of transport due to lower viscosity. Electrochemically determined diffusion coefficients for CO2 in [BMIm][BF4 ]/water systems agree well with values determined by NMR spectroscopy.
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Affiliation(s)
- Alexander V Rudnev
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland.,A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Leninskii prospekt 31, 119991, Moscow, Russia
| | - Yong-Chun Fu
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Ilche Gjuroski
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Florian Stricker
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Julien Furrer
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - Noémi Kovács
- Department of Physical Chemistry, Eötvös Loránd University, Pázmány Péter sétány 1/A, 1117, Budapest, Hungary
| | - Soma Vesztergom
- Department of Physical Chemistry, Eötvös Loránd University, Pázmány Péter sétány 1/A, 1117, Budapest, Hungary
| | - Peter Broekmann
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
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35
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Kapatai G, Sheppard CL, Troxler LJ, Litt DJ, Furrer J, Hilty M, Fry NK. Pneumococcal 23B Molecular Subtype Identified Using Whole Genome Sequencing. Genome Biol Evol 2017; 9:2122-2135. [PMID: 28910966 PMCID: PMC5581491 DOI: 10.1093/gbe/evx092] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/09/2017] [Indexed: 01/20/2023] Open
Abstract
The polysaccharide capsule is a major virulence factor of Streptococcus pneumoniae and the target of all currently licensed pneumococcal vaccines. At present, there are 92 serologically distinct pneumococcal serotypes. Structural and antigenic variation of capsular types is the result of genetic variation within the capsular polysaccharide synthesis (CPS) locus; however, genetic variation may not always result in phenotypic differences which produce novel serotypes. With the introduction of high throughput whole genome sequencing, discovery of novel genotypic variants is not unexpected and this study describes a novel variant of the serotype 23B CPS operon. This novel variant was characterized as a novel genotypic subtype (23B1) with ∼70% homology to the published 23B CPS sequence. High sequence variability was determined in eight cps genes involved in sugar biosynthesis. However, there was no distinction between the classic 23B serotype and 23B1 serologically or in terms of polysaccharide structure. Phylogenetic and eBURST analysis revealed a distinct lineage for 23B1 with multiple clones (UK, Thailand, and USA) that arose at different points during pneumococcal evolution. Analysis of the UK S. pneumoniae isolates (n = 121) revealed an upsurge of 23B1 ST2372 in 2011, after which this previously unseen ST increased to reach 50% proportion of the 23B sequenced isolates from 2013 and remained prevalent within our sequenced isolates from later years. Therefore, although the 23B1 variant appears to have no phenotypic impact and cannot be considered as novel serotype, it appears to have led to a genetic restructuring of the UK serotype 23B population.
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Affiliation(s)
- Georgia Kapatai
- Respiratory and Vaccine Preventable Bacteria Reference Unit, Public Health England, National Infection Service, London, United Kingdom
| | - Carmen L Sheppard
- Respiratory and Vaccine Preventable Bacteria Reference Unit, Public Health England, National Infection Service, London, United Kingdom
| | - Lukas J Troxler
- Institute for Infectious Diseases, University of Bern, Switzerland
| | - David J Litt
- Respiratory and Vaccine Preventable Bacteria Reference Unit, Public Health England, National Infection Service, London, United Kingdom
| | - Julien Furrer
- Department of Chemistry and Biochemistry, University of Bern, Switzerland
| | - Markus Hilty
- Institute for Infectious Diseases, University of Bern, Switzerland.,Department of Infectious Diseases, Bern University Hospital, Inselspital, University of Bern, Switzerland
| | - Norman K Fry
- Respiratory and Vaccine Preventable Bacteria Reference Unit, Public Health England, National Infection Service, London, United Kingdom
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36
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Furrer J. Editorial. Chimia (Aarau) 2017; 71:89. [PMID: 28351453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023] Open
Affiliation(s)
- Julien Furrer
- Department of Chemistry and Biochemistry, University of Bern
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Vermathen M, Diserens G, Vermathen P, Furrer J. Metabolic Profiling of Cells in Response to Drug Treatment using 1H High-resolution Magic Angle Spinning (HR-MAS) NMR Spectroscopy. Chimia (Aarau) 2017; 71:124-129. [PMID: 28351458 DOI: 10.2533/chimia.2017.124] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
High-resolution magic angle spinning (HR-MAS) is an NMR technique that provides access to well resolved liquid-like 1H NMR spectra of semi-solid samples. Therefore, 1H HR-MAS NMR spectroscopy has become an important tool for the direct analysis of biological samples such as tissues and cells in a mostly non-destructive way. Here, we focus on the application of HR-MAS NMR combined with multivariate statistical methods used for metabolic profiling of cells and in particular for the study of cellular metabolic responses to drug exposure. The principles of HR-MAS and the metabolomic approach are briefly described. As an example, a study on the metabolic response of different cell types towards treatment with a highly cytotoxic hexacationic ruthenium metallaprism as potential anti-cancer drug is presented. Specific metabolites and metabolic pathways are suggested to be associated with the cellular response. The study demonstrates the potential of HR-MAS metabolomics applied to cells for addressing the intracellular processes involved in the treatment with organometallic drugs.
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Affiliation(s)
- Martina Vermathen
- Department of Chemistry and Biochemistry University of Bern, Freiestrasse 3 CH-3012 Bern, Switzerland;,
| | - Gaëlle Diserens
- Departments of Clinical Research and Radiology, University and Inselspital Bern, Switzerland
| | - Peter Vermathen
- Departments of Clinical Research and Radiology, University and Inselspital Bern, Switzerland
| | - Julien Furrer
- Department of Chemistry and Biochemistry University of Bern, Freiestrasse 3 CH-3012 Bern, Switzerland;,
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Koceva-Chyła A, Matczak K, Hikisz MP, Durka MK, Kochel MK, Süss-Fink G, Furrer J, Kowalski K. Insights into the in vitro Anticancer Effects of Diruthenium-1. ChemMedChem 2016; 11:2171-2187. [DOI: 10.1002/cmdc.201600315] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Indexed: 01/22/2023]
Affiliation(s)
- Aneta Koceva-Chyła
- Department of Medical Biophysics; Faculty of Biology and Environmental Protection; University of Łódź; Pomorska St. 141/143 90236 Łódź Poland
| | - Karolina Matczak
- Department of Medical Biophysics; Faculty of Biology and Environmental Protection; University of Łódź; Pomorska St. 141/143 90236 Łódź Poland
| | - Msc. Paweł Hikisz
- Department of Medical Biophysics; Faculty of Biology and Environmental Protection; University of Łódź; Pomorska St. 141/143 90236 Łódź Poland
| | - Msc. Kamil Durka
- Department of Medical Biophysics; Faculty of Biology and Environmental Protection; University of Łódź; Pomorska St. 141/143 90236 Łódź Poland
| | - Msc. Krzysztof Kochel
- Department of Medical Biophysics; Faculty of Biology and Environmental Protection; University of Łódź; Pomorska St. 141/143 90236 Łódź Poland
| | - Georg Süss-Fink
- Institut de Chimie; Université de Neuchâtel; Avenue de Bellevaux 51 2000 Neuchâtel Switzerland
| | - Julien Furrer
- Department für Chemie und Biochemie; Universität Bern; Freiestrasse 3 3012 Bern Switzerland
| | - Konrad Kowalski
- Department of Organic Chemistry; Faculty of Chemistry; University of Łódź; Tamka St. 12 91403 Łódź Poland
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Affiliation(s)
- Sebastiano Guerra
- Institut
de Chimie, Université de Neuchâtel, Avenue de Bellevaux 51, CH-2000 Neuchâtel, Switzerland
| | - Thi Le Anh Nguyen
- Institut
de Chimie, Université de Neuchâtel, Avenue de Bellevaux 51, CH-2000 Neuchâtel, Switzerland
| | - Julien Furrer
- Institut
de Chimie, Université de Neuchâtel, Avenue de Bellevaux 51, CH-2000 Neuchâtel, Switzerland
| | - Jean-François Nierengarten
- Laboratoire
de Chimie des Matériaux Moléculaires, Université
de Strasbourg et CNRS (UMR 7509), Ecole Européenne de Chimie, Polymères et Matériaux, 25 rue Becquerel, 67087 Strasbourg, Cedex
2, France
| | - Joaquín Barberá
- Departamento
de Química Orgánica, Facultad de Ciencias-Instituto
de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
| | - Robert Deschenaux
- Institut
de Chimie, Université de Neuchâtel, Avenue de Bellevaux 51, CH-2000 Neuchâtel, Switzerland
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Stíbal D, Geiser L, Süss-Fink G, Furrer J. Hydrolytic behaviour of mono- and dithiolato-bridged dinuclear arene ruthenium complexes and their interactions with biological ligands. RSC Adv 2016. [DOI: 10.1039/c6ra07701c] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Compared to the inert and highly cytotoxic dinuclear p-cymene ruthenium trithiolato complexes, the less cytotoxic mono- and dithiolato complexes readily hydrolyse in aqueous solution and form adducts with cysteine, but do not interact with DNA.
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Affiliation(s)
- David Stíbal
- Institut de Chimie
- Université de Neuchâtel
- CH-2000 Neuchâtel
- Switzerland
| | - Lennart Geiser
- Departement für Chemie und Biochemie
- Universität Bern
- CH-3012 Bern
- Switzerland
| | - Georg Süss-Fink
- Institut de Chimie
- Université de Neuchâtel
- CH-2000 Neuchâtel
- Switzerland
| | - Julien Furrer
- Departement für Chemie und Biochemie
- Universität Bern
- CH-3012 Bern
- Switzerland
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Rudnev AV, Zhumaev UE, Kuzume A, Vesztergom S, Furrer J, Broekmann P, Wandlowski T. The promoting effect of water on the electroreduction of CO 2 in acetonitrile. Electrochim Acta 2016. [DOI: 10.1016/j.electacta.2015.12.088] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Paul LE, Therrien B, Furrer J. Did the presence of a guest in the cavity of an arene ruthenium metallaprism modify its reactivity towards biomolecules? J Organomet Chem 2015. [DOI: 10.1016/j.jorganchem.2015.02.042] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Hädener M, Gjuroski I, Furrer J, Vermathen M. Interactions of Polyvinylpyrrolidone with Chlorin e6-Based Photosensitizers Studied by NMR and Electronic Absorption Spectroscopy. J Phys Chem B 2015; 119:12117-28. [DOI: 10.1021/acs.jpcb.5b05761] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Marianne Hädener
- Department of Chemistry and
Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
| | - Ilche Gjuroski
- Department of Chemistry and
Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
| | - Julien Furrer
- Department of Chemistry and
Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
| | - Martina Vermathen
- Department of Chemistry and
Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
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45
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Hai NTM, Lechner D, Stricker F, Furrer J, Broekmann P. Inside Cover: Combined Secondary Ion Mass Spectrometry Depth Profiling and Focused Ion Beam Analysis of Cu Films Electrodeposited under Oscillatory Conditions (ChemElectroChem 5/2015). ChemElectroChem 2015. [DOI: 10.1002/celc.201590021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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46
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Giannini F, Geiser L, Paul LE, Roder T, Therrien B, Süss-Fink G, Furrer J. Tuning the in vitro cell cytotoxicity of dinuclear arene ruthenium trithiolato complexes: Influence of the arene ligand. J Organomet Chem 2015. [DOI: 10.1016/j.jorganchem.2015.02.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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47
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Hai NTM, Lechner D, Stricker F, Furrer J, Broekmann P. Combined Secondary Ion Mass Spectrometry Depth Profiling and Focused Ion Beam Analysis of Cu Films Electrodeposited under Oscillatory Conditions. ChemElectroChem 2015. [DOI: 10.1002/celc.201402427] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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48
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Giannini F, Bartoloni M, Paul LEH, Süss-Fink G, Reymond JL, Furrer J. Cytotoxic peptide conjugates of dinuclear arene ruthenium trithiolato complexes. Med Chem Commun 2015. [DOI: 10.1039/c4md00433g] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Novel dinuclear arene ruthenium trithiolato complexes containing a water-soluble peptide moiety in one of the three thiolato bridges were designed and evaluated against A2780 human ovarian cancer cells and against their cisplatin-resistant mutant A2780cisR.
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Affiliation(s)
- Federico Giannini
- Departement für Chemie und Biochemie
- Universität Bern
- CH-3012 Bern
- Switzerland
| | - Marco Bartoloni
- Departement für Chemie und Biochemie
- Universität Bern
- CH-3012 Bern
- Switzerland
| | - Lydia E. H. Paul
- Departement für Chemie und Biochemie
- Universität Bern
- CH-3012 Bern
- Switzerland
| | - Georg Süss-Fink
- Institut de Chimie
- Université de Neuchâtel
- CH-2000 Neuchâtel
- Switzerland
| | - Jean-Louis Reymond
- Departement für Chemie und Biochemie
- Universität Bern
- CH-3012 Bern
- Switzerland
| | - Julien Furrer
- Departement für Chemie und Biochemie
- Universität Bern
- CH-3012 Bern
- Switzerland
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Abstract
Interactions between three hexacationic arene ruthenium metallaprisms and human proteins have been studied using NMR spectroscopy, mass spectrometry and circular dichroism spectroscopy, showing that proteins are potential biological targets for these metallaprisms.
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Affiliation(s)
- Lydia E. H. Paul
- Departement für Chemie und Biochemie
- Universität Bern
- CH-3012 Bern
- Switzerland
| | - Bruno Therrien
- Institut de Chimie
- Université de Neuchâtel
- CH-2000 Neuchâtel
- Switzerland
| | - Julien Furrer
- Departement für Chemie und Biochemie
- Universität Bern
- CH-3012 Bern
- Switzerland
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50
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Stíbal D, Therrien B, Giannini F, Paul LEH, Furrer J, Süss-Fink G. Monothiolato-Bridged Dinuclear Arene Ruthenium Complexes: The Missing Link in the Reaction of Arene Ruthenium Dichloride Dimers with Thiols. Eur J Inorg Chem 2014. [DOI: 10.1002/ejic.201402754] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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