Publications by authors named "Ian Levitan"

Rigidified nucleoside derivatives with (N)-methanocarba replacement of ribose have been repurposed as peripheral subtype-selective 5-HT serotonin receptor antagonists for heart and lung fibrosis and intestinal/vascular conditions. 4'-Cyano derivative (MRS8209; , 4.27 nM) was 47-fold (human binding, but not rat and mouse) and 724-fold (functionally) selective at 5-HTR, compared to antitarget 5-HTR, and predicted to form a stable receptor complex using docking and molecular dynamics.

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The NLRP3 inflammasome promotes inflammation in disease, yet the full repertoire of mechanisms regulating its activity is not well delineated. Among established regulatory mechanisms, covalent modification of NLRP3 has emerged as a common route for the pharmacological inactivation of this protein. Here, we show that inhibition of the glycolytic enzyme phosphoglycerate kinase 1 (PGK1) results in the accumulation of methylglyoxal, a reactive metabolite whose increased levels decrease NLRP3 assembly and inflammatory signaling in cells.

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The NLRP3 inflammasome promotes inflammation in disease, yet the full repertoire of mechanisms regulating its activity are not well delineated. Among established regulatory mechanisms, covalent modification of NLRP3 has emerged as a common route for pharmacological inactivation of this protein. Here, we show that inhibition of the glycolytic enzyme PGK1 results in the accumulation of methylglyoxal, a reactive metabolite whose increased levels decrease NLRP3 assembly and inflammatory signaling in cells.

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Protein kinase C (PKC) isoforms regulate many important signaling pathways. Here, we report that PKC activation by phorbol 12-myristate 13-acetate (PMA) enhanced A adenosine receptor (AR)-mediated, but not β-adrenergic receptor-mediated, cAMP accumulation, in H9C2 cardiomyocyte-like and HEK293 cells. In addition to enhancement, PKC (PMA-treatment) also activated AAR with low E (H9C2 and NIH3T3 cells endogenously expressing AAR), or with high E (AAR-overexpressing HEK293 cells) to induce cAMP accumulation.

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Neuromuscular dysfunction is a common feature of mitochondrial diseases and frequently presents as ataxia, spasticity and/or dystonia, all of which can severely impact individuals with mitochondrial diseases. Dystonia is one of the most common symptoms of multiple mitochondrial dysfunctions syndrome 1 (MMDS1), a disease associated with mutations in the causative gene (NFU1) that impair iron-sulfur cluster biogenesis. We have generated Caenorhabditis elegans strains that recreated patient-specific point variants in the C.

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Heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptors (GPCRs) are common drug targets and canonically couple to specific G protein subtypes and β-arrestin adaptor proteins. G protein-mediated signaling and β-arrestin-mediated signaling have been considered separable. We show here that GPCRs promote a direct interaction between G protein subtype family members and β-arrestins regardless of their canonical G protein subtype coupling.

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