Unlabelled: Methapyrilene, [N,N-dimethyl-N'-pyridyl-N'(2-thienylmethyl)-1,2-ethanediamine] (MP) was withdrawn from, clinical use due to reported periportal hepatic necrosis and hepatocarcinogenicity in the rat, via S-oxidation of the thiophene group. In this study MP is used as a model hepatotoxin to further characterise the functional consequences of S-oxidation of the thiophene group in vivo, in rat models and in vitro, in freshly isolated rat hepatocyte suspensions. In vivo histological studies revealed the early depletion of glutathione (GSH), which was confined to the damaged periportal area, in contrast to an increase in GSH levels in the centrilobular region. Additionally, the induction of cell defence was demonstrated by an increase in the protein levels of heme-oxygenase 1 (HO-1) and glutamate cysteine ligase, catalytic subunit (GCLC) in vivo. Histological examination demonstrated that cytotoxicity progresses initially via apoptosis before an increase in necrosis over the 3-day administration. An apoptotic-like mechanism was observed in vitro via the measurement of cytochrome c release and caspase activation.
Conclusion: This study provides evidence for a complex pathway of MP-induced hepatotoxicity which progresses through early adaptation, apoptosis, necrosis and inflammation, all underpinned by the zonal induction and depletion of GSH within the liver.
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http://dx.doi.org/10.1016/j.taap.2009.05.027 | DOI Listing |
J Med Chem
January 2025
Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, P. R. China.
Pyroptosis, an excellent form of immunogenic cell death that can effectively activate antitumor immune responses, is attracting considerable interest as a promising approach for cancer immunotherapy. Immunogenic pyroptosis can recruit and stimulate dendritic cells to provoke further activation and tumor infiltration of T cells by releasing danger-associated molecular patterns, thus improving the tumor response to PD-1/PD-L1 checkpoint blockade immunotherapy. Here, we report the discovery of a bifunctional photosensitizer Nile Violet that can simultaneously trigger caspase-3/GSDME-mediated immunogenic pyroptosis and PD-L1 downregulation for cancer photoimmunotherapy.
View Article and Find Full Text PDFJCI Insight
January 2025
CNRS UMR 5164, INSERM ERL 1303, ImmunoConcEpT, University of Bordeaux, Bordeaux, France.
CD8+ T cells are critical for immune protection against severe COVID-19 during acute infection with SARS-CoV-2. However, the induction of antiviral CD8+ T cell responses varies substantially among infected people, and a better understanding of the mechanisms that underlie such immune heterogeneity is required for pandemic preparedness and risk stratification. In this study, we analyzed SARS-CoV-2-specific CD4+ and CD8+ T cell responses in relation to age, clinical status, and inflammation among patients infected primarily during the initial wave of the pandemic in France or Japan.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
State Key Laboratory of Protein and Plant Genetic Engineering, School of Life Science, Peking University, Beijing 100871, People's Republic of China.
Phycobilisomes (PBS) are the major photosynthetic light-harvesting complexes in cyanobacteria and red algae. While the structures of PBS have been determined in atomic resolutions, how PBS are attached to the reaction centers of photosystems remains less clear. Here, we report that a linker protein (LcpA) is required for the attachment of PBS to photosystem II (PSII) in the cyanobacterium sp.
View Article and Find Full Text PDFDokl Biochem Biophys
January 2025
State Research Center-Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, 123098, Moscow, Russia.
Background: The effects of ionizing radiation (IR) involve a highly orchestrated series of events in cells, including DNA damage and repair, cell death, and changes in the level of proliferation associated with the stage of the cell cycle. A large number of existing studies in literature have examined the activity of genes and their regulators in mammalian cells in response to high doses of ionizing radiation. Although there are many studies, the research in effect of low doses of ionizing radiation remains limited.
View Article and Find Full Text PDFBraz J Microbiol
January 2025
Faculty of Material Science and Engineering, K. N. Toosi University of Technology, Tehran, Iran.
Diabetes is a critical worldwide health problem. Numerous studies have focused on producing recombinant human insulin to address this issue. In this research, the process factors of production of recombinant His-tagged proinsulin in E.
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