2022
Distinct subcellular localisation of intramyocellular lipids and reduced PKCε/PKCθ activity preserve muscle insulin sensitivity in exercise-trained mice
Gaspar R, Lyu K, Hubbard B, Leitner B, Luukkonen P, Hirabara S, Sakuma I, Nasiri A, Zhang D, Kahn M, Cline G, Pauli J, Perry R, Petersen K, Shulman G. Distinct subcellular localisation of intramyocellular lipids and reduced PKCε/PKCθ activity preserve muscle insulin sensitivity in exercise-trained mice. Diabetologia 2022, 66: 567-578. PMID: 36456864, PMCID: PMC11194860, DOI: 10.1007/s00125-022-05838-8.Peer-Reviewed Original ResearchConceptsProtein kinase CsSubcellular compartmentsDistinct subcellular localisationMuscle insulin sensitivityMultiple subcellular compartmentsInsulin receptor kinaseNovel protein kinase CsActivation of PKCεSubcellular localisationPKCθ translocationReceptor kinasePlasma membraneSubcellular distributionTriacylglycerol contentCrucial pathwaysIntramuscular triacylglycerol contentRC miceDiacylglycerolConclusions/interpretationThese resultsPKCεPM compartmentPhosphorylationMuscle triacylglycerol contentSkeletal muscleRecent findingsDyrk1b promotes hepatic lipogenesis by bypassing canonical insulin signaling and directly activating mTORC2 in mice
Bhat N, Narayanan A, Fathzadeh M, Kahn M, Zhang D, Goedeke L, Neogi A, Cardone RL, Kibbey RG, Fernandez-Hernando C, Ginsberg HN, Jain D, Shulman G, Mani A. Dyrk1b promotes hepatic lipogenesis by bypassing canonical insulin signaling and directly activating mTORC2 in mice. Journal Of Clinical Investigation 2022, 132: e153724. PMID: 34855620, PMCID: PMC8803348, DOI: 10.1172/jci153724.Peer-Reviewed Original ResearchConceptsDe novo lipogenesisNonalcoholic steatohepatitisInsulin resistanceHepatic lipogenesisElevated de novo lipogenesisNonalcoholic fatty liver diseaseFatty liver diseaseLiver of patientsHepatic glycogen storageHigh-sucrose dietHepatic insulin resistanceFatty acid uptakeMetabolic syndromeLiver diseaseHepatic steatosisTriacylglycerol secretionNovo lipogenesisHepatic insulinTherapeutic targetImpaired activationAcid uptakeGlycogen storageMouse liverLiverLipogenesis
2014
Muscle-specific activation of Ca2+/calmodulin-dependent protein kinase IV increases whole-body insulin action in mice
Lee HY, Gattu AK, Camporez JP, Kanda S, Guigni B, Kahn M, Zhang D, Galbo T, Birkenfeld AL, Jornayvaz FR, Jurczak MJ, Choi CS, Yan Z, Williams RS, Shulman GI, Samuel VT. Muscle-specific activation of Ca2+/calmodulin-dependent protein kinase IV increases whole-body insulin action in mice. Diabetologia 2014, 57: 1232-1241. PMID: 24718953, PMCID: PMC5634138, DOI: 10.1007/s00125-014-3212-1.Peer-Reviewed Original ResearchConceptsMitochondrial contentDependent protein kinaseDependent protein kinase IVSkeletal muscleInsulin actionMuscle mitochondrial contentInsulin-stimulated glucose uptakeMuscle-specific activationΓ coactivator 1αGlucose uptakePhosphorylation of AktSkeletal muscle insulin actionProtein kinaseOxidative type IMitochondrial biogenesisKinase IVMuscle insulin actionGLUT4 proteinGlucose metabolismInsulin-stimulated whole-body glucose uptakePleiotropic effectsWhole-body glucose uptakeCAMK4Coactivator 1αWhole-body insulin action
2011
Influence of the Hepatic Eukaryotic Initiation Factor 2α (eIF2α) Endoplasmic Reticulum (ER) Stress Response Pathway on Insulin-mediated ER Stress and Hepatic and Peripheral Glucose Metabolism*
Birkenfeld AL, Lee HY, Majumdar S, Jurczak MJ, Camporez JP, Jornayvaz FR, Frederick DW, Guigni B, Kahn M, Zhang D, Weismann D, Arafat AM, Pfeiffer AF, Lieske S, Oyadomari S, Ron D, Samuel VT, Shulman GI. Influence of the Hepatic Eukaryotic Initiation Factor 2α (eIF2α) Endoplasmic Reticulum (ER) Stress Response Pathway on Insulin-mediated ER Stress and Hepatic and Peripheral Glucose Metabolism*. Journal Of Biological Chemistry 2011, 286: 36163-36170. PMID: 21832042, PMCID: PMC3196114, DOI: 10.1074/jbc.m111.228817.Peer-Reviewed Original ResearchConceptsHepatic glucose productionInsulin sensitivityInsulin resistanceCaloric excessER stressHigh-fat diet-fed miceBasal plasma glucose concentrationsGlucose productionIGFBP-3 levelsHepatic ERPeripheral glucose metabolismTissue insulin sensitivityDiet-fed miceHepatic lipid accumulationHigh-fat dietHyperinsulinemic-euglycemic clampHepatic insulin sensitivityInfusion of insulinPlasma glucose concentrationEndoplasmic reticulum stress response pathwayEndoplasmic reticulum stressInsulin-stimulated muscleIGFBP-3Fat dietMuscle glucose
2009
Sensitivity of Lipid Metabolism and Insulin Signaling to Genetic Alterations in Hepatic Peroxisome Proliferator–Activated Receptor-γ Coactivator-1α Expression
Estall JL, Kahn M, Cooper MP, Fisher FM, Wu MK, Laznik D, Qu L, Cohen DE, Shulman GI, Spiegelman BM. Sensitivity of Lipid Metabolism and Insulin Signaling to Genetic Alterations in Hepatic Peroxisome Proliferator–Activated Receptor-γ Coactivator-1α Expression. Diabetes 2009, 58: 1499-1508. PMID: 19366863, PMCID: PMC2699879, DOI: 10.2337/db08-1571.Peer-Reviewed Original ResearchMeSH KeywordsAdipose TissueAnimalsBlood GlucoseBody CompositionCell Culture TechniquesCrosses, GeneticFatty LiverFemaleGene Expression RegulationHepatocytesHomeostasisInsulinInsulin ResistanceIntegrasesKetonesLipidsLiverMiceMice, TransgenicPeroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alphaRNA, Small InterferingTrans-ActivatorsTranscription FactorsTriglyceridesConceptsPGC-1alpha levelsCre/lox systemExpression of genesKey metabolic enzymesKey metabolic pathwaysPGC-1alpha activityPGC-1alpha expressionPeroxisome proliferator-activated receptor gamma coactivatorReceptor γ coactivatorLipid metabolismProliferator-activated receptor gamma coactivatorComplete genetic ablationTranscriptional coactivatorNutrient deprivationReceptor gamma coactivatorPGC-1alphaFatty acid oxidationOxidative phosphorylationMetabolic enzymesLox systemCoactivatorLipid homeostasisMetabolic pathwaysGenetic ablationGenetic alterations
2007
Overexpression of uncoupling protein 3 in skeletal muscle protects against fat-induced insulin resistance
Choi CS, Fillmore JJ, Kim JK, Liu ZX, Kim S, Collier EF, Kulkarni A, Distefano A, Hwang YJ, Kahn M, Chen Y, Yu C, Moore IK, Reznick RM, Higashimori T, Shulman GI. Overexpression of uncoupling protein 3 in skeletal muscle protects against fat-induced insulin resistance. Journal Of Clinical Investigation 2007, 117: 1995-2003. PMID: 17571165, PMCID: PMC1888566, DOI: 10.1172/jci13579.Peer-Reviewed Original ResearchMeSH KeywordsAgingAMP-Activated Protein KinasesAnimalsEnzyme ActivationGene Expression RegulationHormonesHumansInsulinInsulin ResistanceIon ChannelsIsoenzymesLipid MetabolismMaleMiceMice, TransgenicMitochondrial ProteinsMultienzyme ComplexesMuscle, SkeletalProtein Kinase CProtein Kinase C-thetaProtein Serine-Threonine KinasesProto-Oncogene Proteins c-aktUncoupling Protein 3Weight GainConceptsFat-induced insulin resistanceInsulin resistanceSkeletal muscleType 2 diabetes mellitusProtein 3IRS-2-associated PI3K activityHigh-fat dietType 2 diabetesHepatic insulin resistanceWild-type miceInsulin-stimulated glucose uptakeExcellent therapeutic targetInsulin-stimulated insulin receptor substrate 1Fatty acid metabolitesSerine kinase cascadeInsulin receptor substrate-1Intramyocellular fatDiabetes mellitusSkeletal muscle protectsReceptor substrate-1Therapeutic targetTransgenic miceAcid metabolitesPI3K activityGlucose uptakeInhibition of protein kinase Cε prevents hepatic insulin resistance in nonalcoholic fatty liver disease
Samuel VT, Liu ZX, Wang A, Beddow SA, Geisler JG, Kahn M, Zhang XM, Monia BP, Bhanot S, Shulman GI. Inhibition of protein kinase Cε prevents hepatic insulin resistance in nonalcoholic fatty liver disease. Journal Of Clinical Investigation 2007, 117: 739-745. PMID: 17318260, PMCID: PMC1797607, DOI: 10.1172/jci30400.Peer-Reviewed Original ResearchConceptsHepatic insulin resistanceNonalcoholic fatty liver diseaseFatty liver diseaseInsulin resistanceHigh-fat feedingLiver diseaseFat-induced hepatic insulin resistanceType 2 diabetes mellitusType 2 diabetesHepatic fat accumulationNovel therapeutic targetInsulin receptor kinase activityDiabetes mellitusHepatic steatosisFat accumulationRats resultsTherapeutic targetHepatic insulinReceptor kinase activityProtein kinase CεInsulin receptorCausal roleIsoforms of PKCAntisense oligonucleotideRats