1
|
Steinmaurer A, Riedl C, König T, Testa G, Köck U, Bauer J, Lassmann H, Höftberger R, Berger T, Wimmer I, Hametner S. The relation between BTK expression and iron accumulation of myeloid cells in multiple sclerosis. Brain Pathol 2024:e13240. [PMID: 38254312 DOI: 10.1111/bpa.13240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 01/05/2024] [Indexed: 01/24/2024] Open
Abstract
Activation of Bruton's tyrosine kinase (BTK) has been shown to play a crucial role in the proinflammatory response of B cells and myeloid cells upon engagement with B cell, Fc, Toll-like receptor, and distinct chemokine receptors. Previous reports suggest BTK actively contributes to the pathogenesis of multiple sclerosis (MS). The BTK inhibitor Evobrutinib has been shown to reduce the numbers of gadolinium-enhancing lesions and relapses in relapsing-remitting MS patients. In vitro, BTK inhibition resulted in reduced phagocytic activity and modulated BTK-dependent inflammatory signaling of microglia and macrophages. Here, we investigated the protein expression of BTK and CD68 as well as iron accumulation in postmortem control (n = 10) and MS (n = 23) brain tissue, focusing on microglia and macrophages. MS cases encompassed active, chronic active, and inactive lesions. BTK+ and iron+ cells positively correlated across all regions of interests and, along with CD68, revealed highest numbers in the center of active and at the rim of chronic active lesions. We then studied the effect of BTK inhibition in the human immortalized microglia-like HMC3 cell line in vitro. In particular, we loaded HMC3 cells with iron-dextran and subsequently administered the BTK inhibitor Evobrutinib. Iron treatment alone induced a proinflammatory phenotype and increased the expression of iron importers as well as the intracellular iron storage protein ferritin light chain (FTL). BTK inhibition of iron-laden cells dampened the expression of microglia-related inflammatory genes as well as iron-importers, whereas the iron-exporter ferroportin was upregulated. Our data suggest that BTK inhibition not only dampens the proinflammatory response but also reduces iron import and storage in activated microglia and macrophages with possible implications on microglial iron accumulation in chronic active lesions in MS.
Collapse
Affiliation(s)
- Anja Steinmaurer
- Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Christian Riedl
- Division of Neurochemistry and Neuropathology, Medical University of Vienna, Vienna, Austria
| | - Theresa König
- Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Giulia Testa
- Division of Neurochemistry and Neuropathology, Medical University of Vienna, Vienna, Austria
| | - Ulrike Köck
- Department of Neuroimmunology, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Jan Bauer
- Department of Neuroimmunology, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Hans Lassmann
- Department of Neuroimmunology, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Romana Höftberger
- Division of Neurochemistry and Neuropathology, Medical University of Vienna, Vienna, Austria
| | - Thomas Berger
- Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Isabella Wimmer
- Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Simon Hametner
- Division of Neurochemistry and Neuropathology, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
2
|
Dushkov A, Vosáhlová Z, Tzintzarov A, Kalíková K, Křížek T, Ugrinova I. Analysis of the Ibotenic Acid, Muscimol, and Ergosterol Content of an Amanita Muscaria Hydroalcoholic Extract with an Evaluation of Its Cytotoxic Effect against a Panel of Lung Cell Lines In Vitro. Molecules 2023; 28:6824. [PMID: 37836667 PMCID: PMC10574166 DOI: 10.3390/molecules28196824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/20/2023] [Accepted: 09/25/2023] [Indexed: 10/15/2023] Open
Abstract
The fungus Amanita muscaria is universally recognizable for its iconic appearance; it is also widely regarded as poisonous, inedible, and even deadly. In spite of that, there have been documented cases of use of A. muscaria-containing preparations against various diseases, including cancer, to no apparent ill effect. The search for compounds that can be used to treat cancer among various plants and fungi has been intensifying in recent years. In light of this, we describe an HPLC HILIC analytical method for the evaluation of the content of the anticancer compound ergosterol (ERG) and the neuroactive alkaloids ibotenic acid (IBO) and muscimol (MUS) that contribute significantly to the unpleasant physiological syndrome associated with A. muscaria consumption. A 'homemade' A. muscaria tincture made using 80-proof rye vodka as the solvent, an A. muscaria extract made with a standardized water-ethanol solution as the solvent, and fractions obtained from the second extract via liquid-liquid extraction with nonpolar solvents were analyzed. The study also presents the results of capillary zone electrophoresis with contactless conductivity detection and UHPLC-MS/MS analyses of the IBO and MUS content of the two native A. muscaria extracts and an evaluation of the standardized extract's cytotoxic effect against a small panel of lung cell cultures in vitro. Our results show that the standardized extract has a significant cytotoxic effect and does not contain the compounds of interest in any significant quantity.
Collapse
Affiliation(s)
- Alexander Dushkov
- Institute of Molecular Biology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria (A.T.)
| | - Zuzana Vosáhlová
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, 128 00 Prague, Czech Republic (K.K.)
| | - Alexander Tzintzarov
- Institute of Molecular Biology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria (A.T.)
| | - Květa Kalíková
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, 128 00 Prague, Czech Republic (K.K.)
| | - Tomáš Křížek
- Department of Analytical Chemistry, Faculty of Science, Charles University, 128 00 Prague, Czech Republic;
| | - Iva Ugrinova
- Institute of Molecular Biology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria (A.T.)
| |
Collapse
|