Koh SK
Direct and Sequential Bioactivation of Pemigatinib to Reactive Iminium Ion Intermediates Culminate in Mechanism-Based Inactivation of Cytochrome P450 3A
Significance Statement In this study, we reported for the first time the covalent MBI of CYP3A by PEM and deciphered its bioactivation pathway involving the metabolic activation of PEM and its major O-desmethylated metabolite to reactive iminium ion intermediates. Following which, a unique covalent docking methodology was harnessed to unravel the structural and molecular determinants underpinning its inactivation. Findings from our study lay the foundation for future investigation of clinically-relevant drug-drug interactions between PEM and concomitant substrates of CYP3A.
ReadDirect and Sequential Bioactivation of Pemigatinib to Reactive Iminium Ion Intermediates Culminate in Mechanism-Based Inactivation of Cytochrome P450 3A
In this study, we reported for the first time the covalent MBI of CYP3A by PEM and deciphered its bioactivation pathway involving the metabolic activation of PEM and its major O-desmethylated metabolite to reactive iminium ion intermediates. Following which, a unique covalent docking methodology was harnessed to unravel the structural and molecular determinants underpinning its inactivation. Findings from our study lay the foundation for future investigation of clinically-relevant drug-drug interactions between PEM and concomitant substrates of CYP3A.
ReadInfigratinib is a Reversible Inhibitor and Mechanism-based Inactivator of Cytochrome P450 3A4
Infigratinib (INF) is a promising selective inhibitor of fibroblast growth factor receptors 1-3 that has recently been accorded both orphan drug designation and priority review status by the U.S Food and Drug Administration for the treatment of advanced cholangiocarcinoma.
ReadIncreased Protein S-Glutathionylation in Leber’s Hereditary Optic Neuropathy (LHON)
Leber’s hereditary optic neuropathy (LHON, MIM#535000) is the most common form of inherited optic neuropathies and mitochondrial DNA-related diseases. The pathogenicity of mutations in genes encoding components of mitochondrial Complex I is well established, but the underlying pathomechanisms of the disease are still unclear. Hypothesizing that oxidative stress related to Complex I deficiency may increase protein S-glutathionylation, we investigated the proteome-wide S-glutathionylation profiles in LHON (n = 11) and control (n = 7) fibroblasts, using the GluICAT platform that we recently developed. Glutathionylation was also studied in healthy fibroblasts (n = 6) after experimental Complex I inhibition. The significantly increased reactive oxygen species (ROS) production in the LHON group by Complex I was shown experimentally.
ReadReactive Metabolite-induced Protein Glutathionylation: a Potentially Novel Mechanism Underlying Acetaminophen Hepatotoxicity
Although covalent protein binding is established as the pivotal event underpinning acetaminophen (APAP) toxicity, its mechanistic details remain unclear. In this study, we demonstrated that APAP induces widespread protein glutathionylation in a time-, dose- and bioactivation-dependent manner in HepaRG cells.
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