2024
Ceramide synthesis inhibitors prevent lipid-induced insulin resistance through the DAG-PKCε-insulin receptorT1150 phosphorylation pathway
Xu W, Zhang D, Ma Y, Gaspar R, Kahn M, Nasiri A, Murray S, Samuel V, Shulman G. Ceramide synthesis inhibitors prevent lipid-induced insulin resistance through the DAG-PKCε-insulin receptorT1150 phosphorylation pathway. Cell Reports 2024, 43: 114746. PMID: 39302831, DOI: 10.1016/j.celrep.2024.114746.Peer-Reviewed Original ResearchLipid-induced hepatic insulin resistanceHepatic insulin resistancePhosphorylation pathwayAntisense oligonucleotidesCeramide synthesis inhibitorsLipid-induced insulin resistanceMyriocin treatmentCeramide synthesisDihydroceramide desaturaseInsulin resistanceHepatic ceramideMyriocinCeramideCeramide contentInsulin-sensitizing effectsPhosphorylationHepatic insulin sensitivityPathwaySynthetic pathwayDES1Glucose productionSynthesis inhibitorDGAT2DesaturaseInhibition
2020
A Membrane-Bound Diacylglycerol Species Induces PKCϵ-Mediated Hepatic Insulin Resistance
Lyu K, Zhang Y, Zhang D, Kahn M, Ter Horst KW, Rodrigues MRS, Gaspar RC, Hirabara SM, Luukkonen PK, Lee S, Bhanot S, Rinehart J, Blume N, Rasch MG, Serlie MJ, Bogan JS, Cline GW, Samuel VT, Shulman GI. A Membrane-Bound Diacylglycerol Species Induces PKCϵ-Mediated Hepatic Insulin Resistance. Cell Metabolism 2020, 32: 654-664.e5. PMID: 32882164, PMCID: PMC7544641, DOI: 10.1016/j.cmet.2020.08.001.Peer-Reviewed Original ResearchConceptsPlasma membraneEndoplasmic reticulumHigh-fat diet-induced hepatic insulin resistanceSubcellular fractionation methodInsulin receptor kinaseKey lipid speciesHepatic insulin resistanceDiet-induced hepatic insulin resistanceReceptor kinaseDiacylglycerol acyltransferase 2Molecular mechanismsAcute knockdownPhosphorylationLipid dropletsLipid speciesAcyltransferase 2KnockdownLiver-specific overexpressionDAG accumulationPKCϵDAG contentMembraneFractionation methodKinaseMitochondria
2019
Distinct Hepatic PKA and CDK Signaling Pathways Control Activity-Independent Pyruvate Kinase Phosphorylation and Hepatic Glucose Production
Gassaway BM, Cardone RL, Padyana AK, Petersen MC, Judd ET, Hayes S, Tong S, Barber KW, Apostolidi M, Abulizi A, Sheetz JB, Kshitiz, Aerni HR, Gross S, Kung C, Samuel VT, Shulman GI, Kibbey RG, Rinehart J. Distinct Hepatic PKA and CDK Signaling Pathways Control Activity-Independent Pyruvate Kinase Phosphorylation and Hepatic Glucose Production. Cell Reports 2019, 29: 3394-3404.e9. PMID: 31825824, PMCID: PMC6951436, DOI: 10.1016/j.celrep.2019.11.009.Peer-Reviewed Original ResearchConceptsCyclin-dependent kinasesMetabolic control pointPhosphorylation sitesNuclear retentionCDK activityPKL activityDays high-fat dietKinase phosphorylationImportant enzymePyruvate kinaseHigh-fat dietS113KinaseEnzyme kineticsPhosphorylationAdditional control pointsRegulationGlucose productionHepatic glucose productionInsulin resistanceGlycolysisEnzymePKAPathwayActivity
2018
PKCε contributes to lipid-induced insulin resistance through cross talk with p70S6K and through previously unknown regulators of insulin signaling
Gassaway BM, Petersen MC, Surovtseva YV, Barber KW, Sheetz JB, Aerni HR, Merkel JS, Samuel VT, Shulman GI, Rinehart J. PKCε contributes to lipid-induced insulin resistance through cross talk with p70S6K and through previously unknown regulators of insulin signaling. Proceedings Of The National Academy Of Sciences Of The United States Of America 2018, 115: e8996-e9005. PMID: 30181290, PMCID: PMC6156646, DOI: 10.1073/pnas.1804379115.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsAnimals, Genetically ModifiedDiabetes Mellitus, Type 2Diet, High-FatDisease Models, AnimalGene Knockdown TechniquesHumansInsulinInsulin Receptor Substrate ProteinsInsulin ResistanceLipid MetabolismLiverPhosphorylationProtein Kinase C-epsilonProteomicsRatsReceptor, InsulinRibosomal Protein S6Ribosomal Protein S6 Kinases, 70-kDaRNA, Small InterferingSignal TransductionConceptsHigh-fat diet-induced hepatic insulin resistanceDiet-induced hepatic insulin resistanceLipid-induced insulin resistanceProtein phosphorylationSiRNA-based screenProtein kinase C εSet of proteinsCross talkHepatic insulin resistanceQuantitative phosphoproteomicsMotif analysisUnknown regulatorKinase assaysPhosphoproteomic dataCanonical insulinP70S6KInsulin receptorImpact of lipidSystem-level approachPKCεDiacylglycerolPhosphorylationKey mediatorNew therapeutic approachesInsulin resistance
2016
Insulin receptor Thr1160 phosphorylation mediates lipid-induced hepatic insulin resistance
Petersen MC, Madiraju AK, Gassaway BM, Marcel M, Nasiri AR, Butrico G, Marcucci MJ, Zhang D, Abulizi A, Zhang XM, Philbrick W, Hubbard SR, Jurczak MJ, Samuel VT, Rinehart J, Shulman GI. Insulin receptor Thr1160 phosphorylation mediates lipid-induced hepatic insulin resistance. Journal Of Clinical Investigation 2016, 126: 4361-4371. PMID: 27760050, PMCID: PMC5096902, DOI: 10.1172/jci86013.Peer-Reviewed Original ResearchConceptsInsulin receptorKinase activityHigh-fat diet-induced hepatic insulin resistanceKinase activation loopNonalcoholic fatty liver diseaseLipid-induced hepatic insulin resistanceProtein kinase CHepatic insulin resistanceDiet-induced hepatic insulin resistanceDiacylglycerol-mediated activationActivation loopPKCε inhibitionAlanine mutationsInsulin resistanceMolecular mechanismsKinase CCritical pathophysiological rolePathogenesis of T2DMechanistic linkMutantsGlycogen synthesisConsequent inhibitionPhosphorylationActive configurationPKCε