References of "Schofield, Christopher J"
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See detailSelective Inhibitors of a Human Prolyl Hydroxylase (OGFOD1) Involved in Ribosomal Decoding.
Thinnes, Cyrille UL; Lohans, Christopher T.; Abboud, Martine I. et al

in Chemistry (Weinheim an der Bergstrasse, Germany) (2019), 25(8), 2019-2024

Human prolyl hydroxylases are involved in the modification of transcription factors, procollagen, and ribosomal proteins, and are current medicinal chemistry targets. To date, there are few reports on ... [more ▼]

Human prolyl hydroxylases are involved in the modification of transcription factors, procollagen, and ribosomal proteins, and are current medicinal chemistry targets. To date, there are few reports on inhibitors selective for the different types of prolyl hydroxylases. We report a structurally informed template-based strategy for the development of inhibitors selective for the human ribosomal prolyl hydroxylase OGFOD1. These inhibitors did not target the other human oxygenases tested, including the structurally similar hypoxia-inducible transcription factor prolyl hydroxylase, PHD2. [less ▲]

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See detailComplement C1q is hydroxylated by collagen prolyl 4 hydroxylase and is sensitive to off-target inhibition by prolyl hydroxylase domain inhibitors that stabilize hypoxia-inducible factor.
Kiriakidis, Serafim; Hoer, Simon S.; Burrows, Natalie et al

in Kidney international (2017), 92(4), 900-908

Complement C1q is part of the C1 macromolecular complex that mediates the classical complement activation pathway: a major arm of innate immune defense. C1q is composed of A, B, and C chains that require ... [more ▼]

Complement C1q is part of the C1 macromolecular complex that mediates the classical complement activation pathway: a major arm of innate immune defense. C1q is composed of A, B, and C chains that require post-translational prolyl 4-hydroxylation of their N-terminal collagen-like domain to enable the formation of the functional triple helical multimers. The prolyl 4-hydroxylase(s) that hydroxylate C1q have not previously been identified. Recognized prolyl 4-hydroxylases include collagen prolyl-4-hydroxylases (CP4H) and the more recently described prolyl hydroxylase domain (PHD) enzymes that act as oxygen sensors regulating hypoxia-inducible factor (HIF). We show that several small-molecule prolyl hydroxylase inhibitors that activate HIF also potently suppress C1q secretion by human macrophages. However, reducing oxygenation to a level that activates HIF does not compromise C1q hydroxylation. In vitro studies showed that a C1q A chain peptide is not a substrate for PHD2 but is a substrate for CP4H1. Circulating levels of C1q did not differ between wild-type mice or mice with genetic deficits in PHD enzymes, but were reduced by prolyl hydroxylase inhibitors. Thus, C1q is hydroxylated by CP4H, but not the structurally related PHD hydroxylases. Hence, reduction of C1q levels may be an important off-target side effect of small molecule PHD inhibitors developed as treatments for renal anemia. [less ▲]

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See detailMolecular and cellular mechanisms of HIF prolyl hydroxylase inhibitors in clinical trials.
Yeh, Tzu-Lan; Leissing, Thomas M.; Abboud, Martine I. et al

in Chemical science (2017), 8(11), 7651-7668

Inhibition of the human 2-oxoglutarate (2OG) dependent hypoxia inducible factor (HIF) prolyl hydroxylases (human PHD1-3) causes upregulation of HIF, thus promoting erythropoiesis and is therefore of ... [more ▼]

Inhibition of the human 2-oxoglutarate (2OG) dependent hypoxia inducible factor (HIF) prolyl hydroxylases (human PHD1-3) causes upregulation of HIF, thus promoting erythropoiesis and is therefore of therapeutic interest. We describe cellular, biophysical, and biochemical studies comparing four PHD inhibitors currently in clinical trials for anaemia treatment, that describe their mechanisms of action, potency against isolated enzymes and in cells, and selectivities versus representatives of other human 2OG oxygenase subfamilies. The 'clinical' PHD inhibitors are potent inhibitors of PHD catalyzed hydroxylation of the HIF-alpha oxygen dependent degradation domains (ODDs), and selective against most, but not all, representatives of other human 2OG dependent dioxygenase subfamilies. Crystallographic and NMR studies provide insights into the different active site binding modes of the inhibitors. Cell-based results reveal the inhibitors have similar effects on the upregulation of HIF target genes, but differ in the kinetics of their effects and in extent of inhibition of hydroxylation of the N- and C-terminal ODDs; the latter differences correlate with the biophysical observations. [less ▲]

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See detailGlucose Metabolism and Oxygen Availability Govern Reactivation of the Latent Human Retrovirus HTLV-1.
Kulkarni, Anurag; Mateus, Manuel; Thinnes, Cyrille UL et al

in Cell chemical biology (2017), 24(11), 1377-13873

The human retrovirus HTLV-1 causes a hematological malignancy or neuroinflammatory disease in approximately 10% of infected individuals. HTLV-1 primarily infects CD4(+) T lymphocytes and persists as a ... [more ▼]

The human retrovirus HTLV-1 causes a hematological malignancy or neuroinflammatory disease in approximately 10% of infected individuals. HTLV-1 primarily infects CD4(+) T lymphocytes and persists as a provirus integrated in their genome. HTLV-1 appears transcriptionally latent in freshly isolated cells; however, the chronically active anti-HTLV-1 cytotoxic T cell response observed in infected individuals indicates frequent proviral expression in vivo. The kinetics and regulation of HTLV-1 proviral expression in vivo are poorly understood. By using hypoxia, small-molecule hypoxia mimics, and inhibitors of specific metabolic pathways, we show that physiologically relevant levels of hypoxia, as routinely encountered by circulating T cells in the lymphoid organs and bone marrow, significantly enhance HTLV-1 reactivation from latency. Furthermore, culturing naturally infected CD4(+) T cells in glucose-free medium or chemical inhibition of glycolysis or the mitochondrial electron transport chain strongly suppresses HTLV-1 plus-strand transcription. We conclude that glucose metabolism and oxygen tension regulate HTLV-1 proviral latency and reactivation in vivo. [less ▲]

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See detailTherapeutic targeting of oxygen-sensing prolyl hydroxylases abrogates ATF4-dependent neuronal death and improves outcomes after brain hemorrhage in several rodent models.
Karuppagounder, Saravanan S.; Alim, Ishraq; Khim, Soah J. et al

in Science translational medicine (2016), 8(328), 32829

Disability or death due to intracerebral hemorrhage (ICH) is attributed to blood lysis, liberation of iron, and consequent oxidative stress. Iron chelators bind to free iron and prevent neuronal death ... [more ▼]

Disability or death due to intracerebral hemorrhage (ICH) is attributed to blood lysis, liberation of iron, and consequent oxidative stress. Iron chelators bind to free iron and prevent neuronal death induced by oxidative stress and disability due to ICH, but the mechanisms for this effect remain unclear. We show that the hypoxia-inducible factor prolyl hydroxylase domain (HIF-PHD) family of iron-dependent, oxygen-sensing enzymes are effectors of iron chelation. Molecular reduction of the three HIF-PHD enzyme isoforms in the mouse striatum improved functional recovery after ICH. A low-molecular-weight hydroxyquinoline inhibitor of the HIF-PHD enzymes, adaptaquin, reduced neuronal death and behavioral deficits after ICH in several rodent models without affecting total iron or zinc distribution in the brain. Unexpectedly, protection from oxidative death in vitro or from ICH in vivo by adaptaquin was associated with suppression of activity of the prodeath factor ATF4 rather than activation of an HIF-dependent prosurvival pathway. Together, these findings demonstrate that brain-specific inactivation of the HIF-PHD metalloenzymes with the blood-brain barrier-permeable inhibitor adaptaquin can improve functional outcomes after ICH in several rodent models. [less ▲]

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See detailStructure of the ribosomal oxygenase OGFOD1 provides insights into the regio- and stereoselectivity of prolyl hydroxylases.
Horita, Shoichiro; Scotti, John S.; Thinnes, Cyrille UL et al

in Structure (London, England : 1993) (2015), 23(4), 639-52

Post-translational ribosomal protein hydroxylation is catalyzed by 2-oxoglutarate (2OG) and ferrous iron dependent oxygenases, and occurs in prokaryotes and eukaryotes. OGFOD1 catalyzes trans-3 prolyl ... [more ▼]

Post-translational ribosomal protein hydroxylation is catalyzed by 2-oxoglutarate (2OG) and ferrous iron dependent oxygenases, and occurs in prokaryotes and eukaryotes. OGFOD1 catalyzes trans-3 prolyl hydroxylation at Pro62 of the small ribosomal subunit protein uS12 (RPS23) and is conserved from yeasts to humans. We describe crystal structures of the human uS12 prolyl 3-hydroxylase (OGFOD1) and its homolog from Saccharomyces cerevisiae (Tpa1p): OGFOD1 in complex with the broad-spectrum 2OG oxygenase inhibitors; N-oxalylglycine (NOG) and pyridine-2,4-dicarboxylate (2,4-PDCA) to 2.1 and 2.6 A resolution, respectively; and Tpa1p in complex with NOG, 2,4-PDCA, and 1-chloro-4-hydroxyisoquinoline-3-carbonylglycine (a more selective prolyl hydroxylase inhibitor) to 2.8, 1.9, and 1.9 A resolution, respectively. Comparison of uS12 hydroxylase structures with those of other prolyl hydroxylases, including the human hypoxia-inducible factor (HIF) prolyl hydroxylases (PHDs), reveals differences between the prolyl 3- and prolyl 4-hydroxylase active sites, which can be exploited for developing selective inhibitors of the different subfamilies. [less ▲]

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See detailTargeting histone lysine demethylases - progress, challenges, and the future.
Thinnes, Cyrille UL; England, Katherine S.; Kawamura, Akane et al

in Biochimica et biophysica acta (2014), 1839(12), 1416-32

N-Methylation of lysine and arginine residues has emerged as a major mechanism of transcriptional regulation in eukaryotes. In humans, N(epsilon)-methyllysine residue demethylation is catalysed by two ... [more ▼]

N-Methylation of lysine and arginine residues has emerged as a major mechanism of transcriptional regulation in eukaryotes. In humans, N(epsilon)-methyllysine residue demethylation is catalysed by two distinct subfamilies of demethylases (KDMs), the flavin-dependent KDM1 subfamily and the 2-oxoglutarate- (2OG) dependent JmjC subfamily, which both employ oxidative mechanisms. Modulation of histone methylation status is proposed to be important in epigenetic regulation and has substantial medicinal potential for the treatment of diseases including cancer and genetic disorders. This article provides an introduction to the enzymology of the KDMs and the therapeutic possibilities and challenges associated with targeting them, followed by a review of reported KDM inhibitors and their mechanisms of action from kinetic and structural perspectives. [less ▲]

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See detail5-Carboxy-8-hydroxyquinoline is a Broad Spectrum 2-Oxoglutarate Oxygenase Inhibitor which Causes Iron Translocation.
Hopkinson, Richard J.; Tumber, Anthony; Yapp, Clarence et al

in Chemical Science (2013), 4(8), 3110-3117

2-Oxoglutarate and iron dependent oxygenases are therapeutic targets for human diseases. Using a representative 2OG oxygenase panel, we compare the inhibitory activities of 5-carboxy-8-hydroxyquinoline ... [more ▼]

2-Oxoglutarate and iron dependent oxygenases are therapeutic targets for human diseases. Using a representative 2OG oxygenase panel, we compare the inhibitory activities of 5-carboxy-8-hydroxyquinoline (IOX1) and 4-carboxy-8-hydroxyquinoline (4C8HQ) with that of two other commonly used 2OG oxygenase inhibitors, N-oxalylglycine (NOG) and 2,4-pyridinedicarboxylic acid (2,4-PDCA). The results reveal that IOX1 has a broad spectrum of activity, as demonstrated by the inhibition of transcription factor hydroxylases, representatives of all 2OG dependent histone demethylase subfamilies, nucleic acid demethylases and gamma-butyrobetaine hydroxylase. Cellular assays show that, unlike NOG and 2,4-PDCA, IOX1 is active against both cytosolic and nuclear 2OG oxygenases without ester derivatisation. Unexpectedly, crystallographic studies on these oxygenases demonstrate that IOX1, but not 4C8HQ, can cause translocation of the active site metal, revealing a rare example of protein ligand-induced metal movement. [less ▲]

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