Peptides, Glycoconjugates and Metals in Biology

@article{schanne_inertness_2022,
title = {Inertness of Superoxide Dismutase Mimics Mn(II) Complexes Based on an Open-Chain Ligand, Bioactivity, and Detection in Intestinal Epithelial Cells},
author = {Gabrielle Schanne and Martha Zoumpoulaki and G\'{e}raldine Gazzah and Amandine Vincent and Hugues Preud’homme and Ryszard Lobinski and Sylvie Demignot and Philippe Seksik and Nicolas Delsuc and Clotilde Policar},
url = {https://www.hindawi.com/journals/omcl/2022/3858122/},
doi = {10.1155/2022/3858122},
issn = {1942-0900},
year = {2022},
date = {2022-01-01},
urldate = {2022-04-03},
journal = {Oxidative Medicine and Cellular Longevity},
volume = {2022},
pages = {e3858122},
abstract = {Oxidative stress is known to play a major role in the pathogenesis of inflammatory bowel diseases (IBDs), and, in particular, superoxide dismutase (SODs) defenses were shown to be weakened in patients suffering from IBDs. SOD mimics, also called SOD mimetics, as low-molecular-weight complexes reproducing the activity of SOD, constitute promising antioxidant catalytic metallodrugs in the context of IBDs. A Mn(II) complex SOD mimic (Mn1) based on an open-chain diaminoethane ligand exerting antioxidant and anti-inflammatory effects on an intestinal epithelial cellular model was shown to experience metal exchanges between the manganese center and metal ions present in the biological environment (such as Zn(II)) to some degrees. As the resulting complexes (mainly Zn(II)) were shown to be inactive, improving the kinetic inertness of Mn(II) complexes based on open-chain ligands is key to improve their bioactivity in a cellular context. We report here the study of three new Mn(II) complexes resulting from Mn1 functionalization with a cyclohexyl and/or a propyl group meant to limit, respectively, (a) metal exchanges and (b) deprotonation of an amine from the 1,2-diaminoethane central scaffold. The new manganese-based SOD mimics display a higher intrinsic SOD activity and also improved kinetic inertness in metal ion exchange processes (with Zn(II), Cu(II), Ni(II), and Co(II)). They were shown to provide anti-inflammatory and antioxidant effects in cells at lower doses than Mn1 (down to 10 μM). This improvement was due to their higher inertness against metal-assisted dissociation and not to different cellular overall accumulations. Based on its higher inertness, the SOD mimic containing both the propyl and the cyclohexyl moieties was suitable for intracellular detection and quantification by mass spectrometry, quantification, that was achieved by using a 13C-labeled Co-based analog of the SOD mimics as an external heavy standard.},
note = {Publisher: Hindawi},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

@article{Bachollet2022b,
title = {Fluorogenic and Genetic Targeting of a Red-Emitting Molecular Calcium Indicator},
author = {Sylvestre P J T Bachollet and Nicolas Pietrancosta and Jean-Maurice Mallet and Blaise Dumat},
doi = {10.1039/D2CC01792J},
year = {2022},
date = {2022-01-01},
journal = {Chemical Communications},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

@article{Bachollet2022,
title = {An expanded palette of fluorogenic HaloTag probes with enhanced contrast for targeted cellular imaging},
author = {Sylvestre P J T Bachollet and Yuriy Shpinov and Fanny Broch and Hela Benaissa and Arnaud Gautier and Nicolas Pietrancosta and Jean-Maurice Mallet and Blaise Dumat},
url = {http://xlink.rsc.org/?DOI=D1OB02394B},
doi = {10.1039/D1OB02394B},
issn = {1477-0520},
year = {2022},
date = {2022-01-01},
journal = {Organic & Biomolecular Chemistry},
volume = {20},
number = {17},
pages = {3619 - 3628},
publisher = {Royal Society of Chemistry},
abstract = {A palette of fluorogenic molecular rotor probes with emissions from green to NIR was developed for wash-free and multicolor imaging of genetically-encoded HaloTag fusion proteins.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

@article{POLICAR2022102109,
title = {SOD mimics: From the tool box of the chemists to cellular studies},
author = {Clotilde Policar and Jean Bouvet and H\'{e}l\`{e}ne C Bertrand and Nicolas Delsuc},
url = {https://www.sciencedirect.com/science/article/pii/S136759312100154X},
doi = {https://doi.org/10.1016/j.cbpa.2021.102109},
issn = {1367-5931},
year = {2022},
date = {2022-01-01},
journal = {Current Opinion in Chemical Biology},
volume = {67},
pages = {102109},
abstract = {Superoxide dismutases (SODs) are metalloproteins that protect cells against oxidative stress by controlling the concentration of superoxide (O2−) through catalysis of its dismutation. The activity of superoxide dismutases can be mimicked by low-molecular-weight complexes having potential therapeutic applications. This review presents recent strategies for designing efficient SOD mimics, from molecular metal complexes to nanomaterials. Studies of these systems in cells reveal that some SOD mimics, designed to react directly with superoxide, may also indirectly enhance the cellular antioxidant arsenal. Finally, a good understanding of the bioactivity requires information on the cell-penetration, speciation, and subcellular location of the SOD mimics: we will describe recent studies and new techniques that open opportunities for characterizing SOD mimics in biological environments.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

@article{https://doi.org/10.1002/chem.202104424,
title = {Cellular Detection of a Mitochondria Targeted Brominated Vinyl Triphenylamine Optical Probe (TP−Br) by X-Ray Fluorescence Microscopy},
author = {Sounderya Nagarajan and Florent Poyer and Laura Fourmois and Delphine Naud-Martin and Kadda Medjoubi and Andrea Somogyi and Gabrielle Schanne and Lucas Henry and Nicolas Delsuc and Clotilde Policar and Helene C Bertrand and Florence Mahuteau-Betzer},
url = {https://chemistry-europe.onlinelibrary.wiley.com/doi/abs/10.1002/chem.202104424},
doi = {https://doi.org/10.1002/chem.202104424},
year = {2022},
date = {2022-01-01},
journal = {Chemistry \textendash A European Journal},
volume = {28},
number = {15},
pages = {e202104424},
abstract = {Abstract Triphenylamine (TP) derivatives such as two-branch cationic vinylbenzimidazolium triphenylamine TP−2Bzim are promising turn-on fluorescent probes suitable for two-photon imaging, labelling mitochondria in live cells. Here, we designed two TP−2Bzim derivatives as bimodal probes suitable for X-ray fluorescence imaging. The conjugation of the TP core with a rhenium tricarbonyl moiety in the TP−RePyta probe altered the localisation in live cells from mitochondria to lysosomes. The introduction of bromine on the TP core generated the TP−Br probe retaining good photophysical properties and mitochondria labelling in live cells. The influence of calcium channels in the uptake of TP−Br was studied. Synchrotron Radiation X-ray Fluorescence (SXRF) imaging of bromine enabled the detection of TP−Br and suggested a negligible presence of the probe in an unbound state in the incubated cells, a crucial point in the development of these probes. This study paves the way towards the development of TP probes as specific organelle stainers suitable for SXRF imaging.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}