2024
High-fat-diet-induced hepatic insulin resistance per se attenuates murine de novo lipogenesis
Goedeke L, Strober J, Suh R, Paolella L, Li X, Rogers J, Petersen M, Nasiri A, Casals G, Kahn M, Cline G, Samuel V, Shulman G, Vatner D. High-fat-diet-induced hepatic insulin resistance per se attenuates murine de novo lipogenesis. IScience 2024, 27: 111175. PMCID: PMC11550620, DOI: 10.1016/j.isci.2024.111175.Peer-Reviewed Original ResearchDuration of high-fat dietAttenuated insulin signalingHigh-fat dietHepatic insulin resistanceInsulin signalingInsulin stimulationLipogenic substrateStimulation of de novo lipogenesisReduced lipogenesisHFD feedingReduce DNLInsulin resistanceResistance per seLipogenesisInsulin resistance per sePathway selectionGlucose metabolismHepatic IRMiceFat dietSREBP1cINSRCeramide 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
2023
1510-P: Lipid-Induced Renal Cortical Insulin Resistance Perturbs Gluconeogenic and Oxidative Metabolism via an sn-1,2-diacylglycerol-PKCe-Insulin Receptor Kinase Axis In Vivo
HUBBARD B, GASPAR R, ZHANG D, KAHN M, NASIRI A, SHULMAN G. 1510-P: Lipid-Induced Renal Cortical Insulin Resistance Perturbs Gluconeogenic and Oxidative Metabolism via an sn-1,2-diacylglycerol-PKCe-Insulin Receptor Kinase Axis In Vivo. Diabetes 2023, 72 DOI: 10.2337/db23-1510-p.Peer-Reviewed Original ResearchInsulin receptor kinasePyruvate carboxylaseHyperinsulinemic-euglycemic clampMitochondrial pyruvate oxidationInsulin resistanceOxidative metabolismMitochondrial pyruvate carboxylaseReceptor kinaseInhibitory phosphorylationAktS473 phosphorylationKinase axisChow fed miceImpairs insulinPyruvate oxidationKnockin micePhosphorylationKey targetFortress BiotechFed micePKCεDiacylglycerolRenal cortexHFDMetabolismBasal conditions
2022
Dyrk1b 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
2021
335-OR: Lipid-Induced Insulin Resistance in the Renal Cortex Is Associated with Plasma Membrane Sn-1,2-diacylglycerol Accumulation and PKCe Translocation
HUBBARD B, GASPAR R, ZHANG D, KAHN M, NASIRI A, ZHANG X, CLINE G, SHULMAN G. 335-OR: Lipid-Induced Insulin Resistance in the Renal Cortex Is Associated with Plasma Membrane Sn-1,2-diacylglycerol Accumulation and PKCe Translocation. Diabetes 2021, 70 DOI: 10.2337/db21-335-or.Peer-Reviewed Original ResearchHigh-fat dietInsulin receptorInsulin resistanceLipid-Induced Insulin ResistanceRC miceProtein kinase CεRegular chowHFD miceRenal cortexCitrate synthase fluxHyperinsulinemic-euglycemic clamp conditionsAktS473 phosphorylationFatty acid fluxPyruvate oxidationPKCε translocationPyruvate dehydrogenase fluxPhosphorylationDiacylglycerol accumulationHFD feedingFat dietSpouse/partnerFold increaseSynthase fluxTranslocationIonis Pharmaceuticals501-P: Lower Plasma Membrane Sn-1,2-Diacylglycerol Content and PKCepsilon/theta Activity Explain the Athlete’s Paradox
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. 501-P: Lower Plasma Membrane Sn-1,2-Diacylglycerol Content and PKCepsilon/theta Activity Explain the Athlete’s Paradox. Diabetes 2021, 70 DOI: 10.2337/db21-501-p.Peer-Reviewed Original ResearchHigh-fat diet feedingMuscle insulin sensitivityEX miceInsulin sensitivitySpouse/partnerGlucose toleranceIntramyocellular lipidsAthlete's paradoxRC micePKCθ translocationHyperinsulinemic-euglycemic clamp studiesGilead SciencesJanssen ResearchMuscle TAG contentMuscle triglyceride contentMale C57BL/6J miceImproved glucose toleranceNovo NordiskMuscle insulin resistanceNovo Nordisk FoundationBoehringer Ingelheim PharmaceuticalsChow feedingHFD groupHFD miceInsulin resistance
2020
Membrane-bound sn-1,2-diacylglycerols explain the dissociation of hepatic insulin resistance from hepatic steatosis in MTTP knockout mice
Abulizi A, Vatner DF, Ye Z, Wang Y, Camporez JP, Zhang D, Kahn M, Lyu K, Sirwi A, Cline GW, Hussain MM, Aspichueta P, Samuel VT, Shulman GI. Membrane-bound sn-1,2-diacylglycerols explain the dissociation of hepatic insulin resistance from hepatic steatosis in MTTP knockout mice. Journal Of Lipid Research 2020, 61: 1565-1576. PMID: 32907986, PMCID: PMC7707176, DOI: 10.1194/jlr.ra119000586.Peer-Reviewed Original ResearchConceptsHepatic insulin resistanceInsulin resistanceHepatic insulin sensitivityHepatic steatosisLipid-induced hepatic insulin resistancePKCε activationInsulin sensitivityKnockout miceNormal hepatic insulin sensitivityWild-type control miceHepatic ceramide contentHyperinsulinemic-euglycemic clampComprehensive metabolic phenotypingLipid dropletsHepatic DAG contentDAG contentGlucose intoleranceControl miceMTTP activityHepatic insulinAnimal modelsSteatosisAKT Ser/ThrMiceMetabolic phenotyping
2019
Hepatic insulin sensitivity is improved in high‐fat diet‐fed Park2 knockout mice in association with increased hepatic AMPK activation and reduced steatosis
Edmunds LR, Huckestein BR, Kahn M, Zhang D, Chu Y, Zhang Y, Wendell SG, Shulman GI, Jurczak MJ. Hepatic insulin sensitivity is improved in high‐fat diet‐fed Park2 knockout mice in association with increased hepatic AMPK activation and reduced steatosis. Physiological Reports 2019, 7: e14281. PMID: 31724300, PMCID: PMC6854109, DOI: 10.14814/phy2.14281.Peer-Reviewed Original ResearchConceptsPark2 KO miceHepatic insulin sensitivityKO miceInsulin sensitivityInsulin resistanceShort-term HFD feedingDiet-induced hepatic insulin resistanceWhole-body insulin sensitivityPark2 knockout miceImproved hepatic insulin sensitivityDiet-induced obesityHigh-fat dietBioactive lipid speciesTumor necrosis factorHepatic insulin resistanceHepatic AMPK activationNegative energy balanceEndoplasmic reticulum stress responseRegular chowCytokine levelsHFD feedingReduced steatosisChronic HFDInterleukin-6Necrosis factor266-OR: Plasma Membrane sn-1,2 Diacylglycerol Mediates Lipid-Induced Hepatic Insulin Resistance
LYU K, ZHANG Y, ZHANG D, KAHN M, NOZAKI Y, BHANOT S, BOGAN J, CLINE G, SAMUEL V, SHULMAN G. 266-OR: Plasma Membrane sn-1,2 Diacylglycerol Mediates Lipid-Induced Hepatic Insulin Resistance. Diabetes 2019, 68 DOI: 10.2337/db19-266-or.Peer-Reviewed Original ResearchHepatic insulin resistanceInsulin resistanceExogenous fatty acidsInsulin actionLipid dropletsHepatic ceramide contentHyperinsulinemic-euglycemic clampHepatic insulin actionBioactive lipid speciesHepatic glucose productionChow-fed ratsHepatic diacylglycerol contentAdvisory PanelFatty acidsHepatic steatosisImpaired suppressionSingle doseSpouse/partnerGlucose productionPKCε activationJanssen ResearchAcute knockdownCeramide contentNational InstituteReceptor kinase activation19-OR: Controlled-Release Mitochondrial Protonophore (CRMP) Reverses Hypertriglyceridemia and Hepatic Steatosis in Dysmetabolic Nonhuman Primates
GOEDEKE L, ROMERAL V, BUTRICO G, KAHN M, DUFOUR S, ZHANG X, CLINE G, PETERSEN K, CHNG K, SHULMAN G. 19-OR: Controlled-Release Mitochondrial Protonophore (CRMP) Reverses Hypertriglyceridemia and Hepatic Steatosis in Dysmetabolic Nonhuman Primates. Diabetes 2019, 68 DOI: 10.2337/db19-19-or.Peer-Reviewed Original ResearchControlled-release mitochondrial protonophoreSpouse/partnerCRMP treatmentInsulin resistanceDiet-induced rodent modelJanssen ResearchReversal of hypertriglyceridemiaNAFLD/NASHInflammation/fibrosisNonhuman primate modelMitochondrial protonophoreEndogenous glucose productionHepatic insulin resistanceHepatic acetyl-CoA contentAdvisory PanelMitochondrial fat oxidationMetabolic syndromeFatty liverHepatic steatosisAdverse reactionsHepatic triglyceridesAcetyl-CoA contentPrimate modelNovo Nordisk A/S.Food intake
2015
Hepatic insulin resistance and increased hepatic glucose production in mice lacking Fgf21
Camporez JP, Asrih M, Zhang D, Kahn M, Samuel VT, Jurczak MJ, Jornayvaz FR. Hepatic insulin resistance and increased hepatic glucose production in mice lacking Fgf21. Journal Of Endocrinology 2015, 226: 207-217. PMID: 26203166, DOI: 10.1530/joe-15-0136.Peer-Reviewed Original ResearchConceptsHepatic insulin resistanceFGF21 KO miceInsulin resistanceHepatic glucose productionKetogenic dietKO miceHepatic glucoseLipid metabolismGlucose productionFibroblast growth factor 21Littermate WT controlsRole of FGF21Growth factor 21Plasma glucagon levelsType 2 diabetesPotential pharmacological agentsFGF21 resistanceGlucagon levelsFactor 21Fat massMale miceWT littermatesPharmacological agentsWT controlsInsulin action
2013
Saturated and unsaturated fat induce hepatic insulin resistance independently of TLR-4 signaling and ceramide synthesis in vivo
Galbo T, Perry RJ, Jurczak MJ, Camporez J, Alves TC, Kahn M, Guigni BA, Serr J, Zhang D, Bhanot S, Samuel VT, Shulman GI. Saturated and unsaturated fat induce hepatic insulin resistance independently of TLR-4 signaling and ceramide synthesis in vivo. Proceedings Of The National Academy Of Sciences Of The United States Of America 2013, 110: 12780-12785. PMID: 23840067, PMCID: PMC3732992, DOI: 10.1073/pnas.1311176110.Peer-Reviewed Original ResearchConceptsHepatic insulin resistanceFat-induced hepatic insulin resistanceInsulin resistanceToll-like receptor 4 receptorTLR-4 knockout miceFat-induced insulin resistanceTLR-4 activationTLR-4 signalingType 2 diabetesImpairment of insulinInhibition of insulinCeramide synthesisActivation of PKCεTLR-4Hepatic steatosisHepatic accumulationKnockout miceIRS-2 signalingReceptor signalingCeramide accumulationAntisense oligonucleotideInsulinPrimary eventImpairmentFatty acidsTargeting Pyruvate Carboxylase Reduces Gluconeogenesis and Adiposity and Improves Insulin Resistance
Kumashiro N, Beddow SA, Vatner DF, Majumdar SK, Cantley JL, Guebre-Egziabher F, Fat I, Guigni B, Jurczak MJ, Birkenfeld AL, Kahn M, Perler BK, Puchowicz MA, Manchem VP, Bhanot S, Still CD, Gerhard GS, Petersen KF, Cline GW, Shulman GI, Samuel VT. Targeting Pyruvate Carboxylase Reduces Gluconeogenesis and Adiposity and Improves Insulin Resistance. Diabetes 2013, 62: 2183-2194. PMID: 23423574, PMCID: PMC3712050, DOI: 10.2337/db12-1311.Peer-Reviewed Original ResearchConceptsPyruvate carboxylaseAntisense oligonucleotideHepatocyte fatty acid oxidationInsulin resistanceNonalcoholic fatty liver diseaseZucker diabetic fatty ratsHigh fat-fed ratsFatty liver diseaseLiver biopsy specimensDiabetic fatty ratsPlasma lipid concentrationsType 2 diabetesHepatic insulin sensitivityHuman liver biopsy specimensEndogenous glucose productionHepatic insulin resistancePlasma glucose concentrationPotential therapeutic approachSpecific antisense oligonucleotideFat-fed ratsCarboxylaseFatty acid oxidationDe novo fatty acid synthesisLiver diseaseTissue-specific inhibitionCellular Mechanisms by Which FGF21 Improves Insulin Sensitivity in Male Mice
Camporez JP, Jornayvaz FR, Petersen MC, Pesta D, Guigni BA, Serr J, Zhang D, Kahn M, Samuel VT, Jurczak MJ, Shulman GI. Cellular Mechanisms by Which FGF21 Improves Insulin Sensitivity in Male Mice. Endocrinology 2013, 154: 3099-3109. PMID: 23766126, PMCID: PMC3749479, DOI: 10.1210/en.2013-1191.Peer-Reviewed Original ResearchMeSH KeywordsAdipose Tissue, BrownAnimalsCells, CulturedDiet, High-FatDrug ImplantsEnergy MetabolismFibroblast Growth FactorsGlucose IntoleranceHumansInfusions, SubcutaneousInsulin ResistanceIsoenzymesLipectomyLipid MetabolismLiverMaleMiceMice, Inbred C57BLMuscle, SkeletalProtein Kinase CProtein Kinase C-epsilonProtein Kinase C-thetaRecombinant ProteinsConceptsType 2 diabetesInsulin resistanceRegular chowInsulin sensitivityInsulin actionNonalcoholic fatty liver diseaseFibroblast growth factor 21Fatty liver diseasePeripheral insulin sensitivityEffects of FGF21HFD-fed miceGrowth factor 21High-fat dietCellular mechanismsWild-type miceWhite adipose tissueMuscle insulin resistanceMuscle ceramide contentProtein kinase Cε activationFGF21 administrationLiver diseaseFactor 21Male miceNovel therapiesAdipose tissueCellular Mechanism by Which Estradiol Protects Female Ovariectomized Mice From High-Fat Diet-Induced Hepatic and Muscle Insulin Resistance
Camporez JP, Jornayvaz FR, Lee HY, Kanda S, Guigni BA, Kahn M, Samuel VT, Carvalho CR, Petersen KF, Jurczak MJ, Shulman GI. Cellular Mechanism by Which Estradiol Protects Female Ovariectomized Mice From High-Fat Diet-Induced Hepatic and Muscle Insulin Resistance. Endocrinology 2013, 154: 1021-1028. PMID: 23364948, PMCID: PMC3578999, DOI: 10.1210/en.2012-1989.Peer-Reviewed Original ResearchConceptsEstrogen replacement therapyOVX miceMuscle insulin sensitivityMuscle insulin resistanceInsulin resistanceInsulin sensitivityReplacement therapyHigh-fat diet feedingWhole-body insulin resistanceWhole-body insulin sensitivityFemale ovariectomized miceEctopic lipid depositionWhole-body energy expenditureType 2 diabetesEnergy expenditureWeeks of ageWhole-body energy homeostasisProtein kinase Cε activationHepatic DAG contentLivers of shamPostmenopausal womenSham miceOvariectomized miceGlucose toleranceE2 treatmentCGI-58 knockdown sequesters diacylglycerols in lipid droplets/ER-preventing diacylglycerol-mediated hepatic insulin resistance
Cantley JL, Yoshimura T, Camporez JP, Zhang D, Jornayvaz FR, Kumashiro N, Guebre-Egziabher F, Jurczak MJ, Kahn M, Guigni BA, Serr J, Hankin J, Murphy RC, Cline GW, Bhanot S, Manchem VP, Brown JM, Samuel VT, Shulman GI. CGI-58 knockdown sequesters diacylglycerols in lipid droplets/ER-preventing diacylglycerol-mediated hepatic insulin resistance. Proceedings Of The National Academy Of Sciences Of The United States Of America 2013, 110: 1869-1874. PMID: 23302688, PMCID: PMC3562813, DOI: 10.1073/pnas.1219456110.Peer-Reviewed Original ResearchMeSH Keywords1-Acylglycerol-3-Phosphate O-AcyltransferaseAdipose Tissue, WhiteAnimalsCell MembraneDiet, High-FatDiglyceridesEndoplasmic ReticulumGene ExpressionGene Knockdown TechniquesHumansImmunoblottingInjections, IntraperitonealInsulin ResistanceLipidsLiverMaleMiceMice, Inbred C57BLOligonucleotides, AntisenseProtein Kinase C-epsilonProtein TransportReverse Transcriptase Polymerase Chain ReactionConceptsHepatic insulin resistanceInsulin resistanceHepatic steatosisCGI-58 knockdownHigh-fat fed miceHyperinsulinemic-euglycemic clamp studiesSevere hepatic steatosisCGI-58 expressionFat-fed miceLipid-induced hepatic insulin resistanceChanarin-Dorfman syndromeComparative gene identification-58Lipid droplet-associated proteinAdipose triglyceride lipaseDroplet-associated proteinAntisense oligonucleotide treatmentInsulin sensitivityASO treatmentClamp studiesLipotoxic conditionsKnockdown miceCGI-58PKCε activationMiceTriglyceride lipase
2012
Fatty acid amide hydrolase ablation promotes ectopic lipid storage and insulin resistance due to centrally mediated hypothyroidism
Brown WH, Gillum MP, Lee HY, Camporez JP, Zhang XM, Jeong JK, Alves TC, Erion DM, Guigni BA, Kahn M, Samuel VT, Cravatt BF, Diano S, Shulman GI. Fatty acid amide hydrolase ablation promotes ectopic lipid storage and insulin resistance due to centrally mediated hypothyroidism. Proceedings Of The National Academy Of Sciences Of The United States Of America 2012, 109: 14966-14971. PMID: 22912404, PMCID: PMC3443187, DOI: 10.1073/pnas.1212887109.Peer-Reviewed Original ResearchMeSH KeywordsAmidesAmidohydrolasesAnalysis of VarianceAnimalsArachidonic AcidsChromatography, LiquidEndocannabinoidsEnergy MetabolismEthanolaminesHypothyroidismImmunoblottingInsulin ResistanceMiceMice, KnockoutPalmitic AcidsPolymerase Chain ReactionPolyunsaturated AlkamidesPPAR gammaTandem Mass SpectrometryThyrotropinThyrotropin-Releasing HormoneThyroxineTriiodothyronineConceptsEctopic lipid storageHepatic insulin resistanceInsulin resistanceEnergy expenditureDiet-induced hepatic insulin resistanceHypothalamic thyrotropin-releasing hormoneFatty acid amide hydrolase knockout miceThyroid-stimulating hormoneThyrotropin-releasing hormoneLipid storageDeiodinase 2 expressionReduced mRNA expressionProtein kinase Cε activationHepatic diacylglycerol contentPituitary thyroid-stimulating hormoneExcess energy storageFAAH deletionKnockout miceReceptor γThyroid axisThyroxine concentrationsMRNA expressionMiceHypothyroidismFAAH
2011
Cellular mechanism of insulin resistance in nonalcoholic fatty liver disease
Kumashiro N, Erion DM, Zhang D, Kahn M, Beddow SA, Chu X, Still CD, Gerhard GS, Han X, Dziura J, Petersen KF, Samuel VT, Shulman GI. Cellular mechanism of insulin resistance in nonalcoholic fatty liver disease. Proceedings Of The National Academy Of Sciences Of The United States Of America 2011, 108: 16381-16385. PMID: 21930939, PMCID: PMC3182681, DOI: 10.1073/pnas.1113359108.Peer-Reviewed Original ResearchConceptsNonalcoholic fatty liver diseaseFatty liver diseaseHepatic DAG contentInsulin resistanceHepatic insulin resistanceLiver diseaseHepatic steatosisCellular mechanismsHomeostatic model assessmentInsulin resistance indexMarkers of inflammationType 2 diabetesER stress markersLipid dropletsHepatic diacylglycerol contentEndoplasmic reticulum stressActivation of PKCεLiver biopsyNondiabetic individualsHepatocellular lipidsInsulin sensitivityCytoplasmic lipid dropletsDAG contentResistance indexAnimal modelsInfluence 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 glucoseRegulation of hepatic fat and glucose oxidation in rats with lipid‐induced hepatic insulin resistance
Alves TC, Befroy DE, Kibbey RG, Kahn M, Codella R, Carvalho RA, Petersen K, Shulman GI. Regulation of hepatic fat and glucose oxidation in rats with lipid‐induced hepatic insulin resistance. Hepatology 2011, 53: 1175-1181. PMID: 21400553, PMCID: PMC3077048, DOI: 10.1002/hep.24170.Peer-Reviewed Original ResearchConceptsLipid-induced hepatic insulin resistanceHepatic insulin resistanceInsulin resistanceTricarboxylic acid fluxFatty acid oxidationPyruvate dehydrogenaseHyperinsulinemic-euglycemic clampHyperinsulinemic-hyperglycemic clampInfusion of somatostatinSubstrate availabilityHigh-fat dietPlasma glucose concentrationRegulationCritical rolePyruvate dehydrogenase fluxHepatic fatHyperglycemic clampAcid oxidationAwake ratsBasal concentrations