2022
Ethnic and gender differences in hepatic lipid content and related cardiometabolic parameters in lean individuals
Petersen KF, Dufour S, Li F, Rothman DL, Shulman GI. Ethnic and gender differences in hepatic lipid content and related cardiometabolic parameters in lean individuals. JCI Insight 2022, 7 PMID: 35167495, PMCID: PMC9057590, DOI: 10.1172/jci.insight.157906.Peer-Reviewed Original ResearchConceptsCardiometabolic risk factorsInsulin resistanceRisk factorsHDL cholesterolLDL cholesterolTotal cholesterolLean individualsMatsuda insulin sensitivity indexAI menCardiovascular risk factorsHomeostatic model assessmentHepatic triglyceride contentInsulin sensitivity indexType 2 diabetesHepatic lipid contentNovo Nordisk FoundationUric acid concentrationCardiometabolic parametersCardiovascular riskPremenopausal womenFatty liverPlasma insulinInsulin sensitivityPlasma concentrationsModel assessmentSex‐ and strain‐specific effects of mitochondrial uncoupling on age‐related metabolic diseases in high‐fat diet‐fed mice
Goedeke L, Murt KN, Di Francesco A, Camporez JP, Nasiri AR, Wang Y, Zhang X, Cline GW, de Cabo R, Shulman GI. Sex‐ and strain‐specific effects of mitochondrial uncoupling on age‐related metabolic diseases in high‐fat diet‐fed mice. Aging Cell 2022, 21: e13539. PMID: 35088525, PMCID: PMC8844126, DOI: 10.1111/acel.13539.Peer-Reviewed Original ResearchConceptsControlled-release mitochondrial protonophoreAge-related metabolic diseasesHepatocellular carcinomaMetabolic diseasesHigh-fat diet-fed miceProtein kinase C epsilon activationDiet-induced obese miceWhole-body energy expenditureC57BL/6J male miceDiet-fed miceHigh-fat dietHepatic lipid peroxidationHepatic lipid contentMitochondrial uncouplingHepatic insulin resistanceHigh therapeutic indexHepatic mitochondrial biogenesisStrain-specific effectsSex-specific mannerCRMP treatmentHFD feedingUnwanted side effectsObese miceInsulin resistanceChronic ingestion
2021
IL-27 signalling promotes adipocyte thermogenesis and energy expenditure
Wang Q, Li D, Cao G, Shi Q, Zhu J, Zhang M, Cheng H, Wen Q, Xu H, Zhu L, Zhang H, Perry RJ, Spadaro O, Yang Y, He S, Chen Y, Wang B, Li G, Liu Z, Yang C, Wu X, Zhou L, Zhou Q, Ju Z, Lu H, Xin Y, Yang X, Wang C, Liu Y, Shulman GI, Dixit VD, Lu L, Yang H, Flavell RA, Yin Z. IL-27 signalling promotes adipocyte thermogenesis and energy expenditure. Nature 2021, 600: 314-318. PMID: 34819664, DOI: 10.1038/s41586-021-04127-5.Peer-Reviewed Original ResearchMeSH KeywordsAdipocytesAnimalsBariatric SurgeryDisease Models, AnimalEnergy MetabolismFemaleHumansInsulin ResistanceInterleukin-27MaleMiceObesityP38 Mitogen-Activated Protein KinasesPeroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alphaReceptors, InterleukinSignal TransductionThermogenesisUncoupling Protein 1ConceptsIL-27Beige adipose tissueAdipose tissueSerum IL-27Diet-induced obesityBariatric surgeryMetabolic morbidityImmunological factorsInsulin resistanceObesity showTherapeutic administrationMetabolic disordersMouse modelObesityPromising targetEnergy expenditureSignaling promotesThermogenesisBody temperatureMetabolic programsImportant roleTissueCritical roleImmunotherapyMorbidityCIDEA expression in SAT from adolescent girls with obesity and unfavorable patterns of abdominal fat distribution
Tarabra E, Nouws J, Vash‐Margita A, Hellerstein M, Shabanova V, McCollum S, Pierpont B, Zhao D, Shulman GI, Caprio S. CIDEA expression in SAT from adolescent girls with obesity and unfavorable patterns of abdominal fat distribution. Obesity 2021, 29: 2068-2080. PMID: 34672413, PMCID: PMC8612981, DOI: 10.1002/oby.23295.Peer-Reviewed Original ResearchConceptsAbdominal fat distributionVisceral adipose tissueCIDEA expressionFat distributionProtein levelsAbdominal SATAdolescent girlsHigher visceral adipose tissueSubcutaneous adipose tissue biopsiesAdipose tissue biopsiesReverse transcription-polymerase chain reactionTranscription-polymerase chain reactionMagnetic resonance imagingWeight gain effectsExpression of CIDEAAdipocyte dysfunctionSAT biopsiesAdipose lipidsInsulin resistanceAdipocyte hypertrophySmall adipocytesAdipose tissueTissue biopsiesUnfavorable patternsStrong inverse correlationValidation of a Gas Chromatography-Mass Spectrometry Method for the Measurement of the Redox State Metabolic Ratios Lactate/Pyruvate and β-Hydroxybutyrate/Acetoacetate in Biological Samples
Wijngaard R, Perramón M, Parra-Robert M, Hidalgo S, Butrico G, Morales-Ruiz M, Zeng M, Casals E, Jiménez W, Fernández-Varo G, Shulman GI, Cline GW, Casals G. Validation of a Gas Chromatography-Mass Spectrometry Method for the Measurement of the Redox State Metabolic Ratios Lactate/Pyruvate and β-Hydroxybutyrate/Acetoacetate in Biological Samples. International Journal Of Molecular Sciences 2021, 22: 4752. PMID: 33946157, PMCID: PMC8125771, DOI: 10.3390/ijms22094752.Peer-Reviewed Original Research
2020
Effect of a Low-Fat Vegan Diet on Body Weight, Insulin Sensitivity, Postprandial Metabolism, and Intramyocellular and Hepatocellular Lipid Levels in Overweight Adults
Kahleova H, Petersen KF, Shulman GI, Alwarith J, Rembert E, Tura A, Hill M, Holubkov R, Barnard ND. Effect of a Low-Fat Vegan Diet on Body Weight, Insulin Sensitivity, Postprandial Metabolism, and Intramyocellular and Hepatocellular Lipid Levels in Overweight Adults. JAMA Network Open 2020, 3: e2025454. PMID: 33252690, PMCID: PMC7705596, DOI: 10.1001/jamanetworkopen.2020.25454.Peer-Reviewed Original ResearchMeSH KeywordsAbsorptiometry, PhotonAdultAgedBlood GlucoseBody CompositionBody WeightCholesterolCholesterol, HDLCholesterol, LDLC-PeptideDiet, Fat-RestrictedDiet, VeganEnergy IntakeEnergy MetabolismFemaleGlycated HemoglobinHepatocytesHumansInsulinInsulin ResistanceIntra-Abdominal FatLipid MetabolismLiverMaleMiddle AgedMuscle Fibers, SkeletalMuscle, SkeletalObesityOverweightPostprandial PeriodProton Magnetic Resonance SpectroscopyTriglyceridesConceptsLow-fat vegan dietHomeostasis model assessment indexIntramyocellular lipid levelsModel assessment indexIntervention groupLipid levelsBody weightInsulin resistancePostprandial metabolismVegan dietOverweight adultsDietary interventionInsulin sensitivityThermic effectControl groupPlant-based dietary interventionDual X-ray absorptiometryInsulin resistance leadExcess body weightInsulin sensitivity indexType 2 diabetesMajor health problemProton magnetic resonance spectroscopyX-ray absorptiometrySubset of participantsThe omentum of obese girls harbors small adipocytes and browning transcripts
Tarabra E, Nouws J, Vash-Margita A, Nadzam GS, Goldberg-Gell R, Van Name M, Pierpont B, Knight J, Shulman GI, Caprio S. The omentum of obese girls harbors small adipocytes and browning transcripts. JCI Insight 2020, 5 PMID: 32125283, PMCID: PMC7213797, DOI: 10.1172/jci.insight.135448.Peer-Reviewed Original ResearchConceptsSubcutaneous adipose tissueSAT depotsSleeve gastrectomySevere obesityInsulin resistanceInsulin sensitivitySmall adipocytesAdipose tissueAbdominal subcutaneous adipose tissueWeight lossType 2 diabetesOmental adipose tissueSubgroup of subjectsTranscriptomic profilesSAT biopsiesAdipocyte sizeObese girlsCardiovascular diseaseEffect of a ketogenic diet on hepatic steatosis and hepatic mitochondrial metabolism in nonalcoholic fatty liver disease
Luukkonen PK, Dufour S, Lyu K, Zhang XM, Hakkarainen A, Lehtimäki TE, Cline GW, Petersen KF, Shulman GI, Yki-Järvinen H. Effect of a ketogenic diet on hepatic steatosis and hepatic mitochondrial metabolism in nonalcoholic fatty liver disease. Proceedings Of The National Academy Of Sciences Of The United States Of America 2020, 117: 7347-7354. PMID: 32179679, PMCID: PMC7132133, DOI: 10.1073/pnas.1922344117.Peer-Reviewed Original ResearchMeSH KeywordsBody CompositionCitrate (si)-SynthaseDiet, KetogenicFatty AcidsFatty Acids, NonesterifiedFatty LiverFemaleHumansInsulinInsulin ResistanceLipoproteins, VLDLLiverMaleMiddle AgedMitochondriaNon-alcoholic Fatty Liver DiseaseObesityOverweightOxidation-ReductionPyruvate CarboxylaseTriglyceridesConceptsNonalcoholic fatty liver diseaseFatty liver diseaseIntrahepatic triglyceridesKetogenic dietHepatic insulin resistanceNonesterified fatty acidsInsulin resistanceLiver diseaseOverweight/obese subjectsHepatic mitochondrial redox stateSerum insulin concentrationsHepatic mitochondrial metabolismProton magnetic resonance spectroscopyStable isotope infusionKD dietObese subjectsFatty acidsPlasma leptinHepatic steatosisInsulin concentrationsNEFA concentrationsBody weightTriiodothyronine concentrationsIsotope infusionWeight lossRegulation of adipose tissue inflammation by interleukin 6
Han MS, White A, Perry RJ, Camporez JP, Hidalgo J, Shulman GI, Davis RJ. Regulation of adipose tissue inflammation by interleukin 6. Proceedings Of The National Academy Of Sciences Of The United States Of America 2020, 117: 2751-2760. PMID: 31980524, PMCID: PMC7022151, DOI: 10.1073/pnas.1920004117.Peer-Reviewed Original ResearchConceptsInterleukin-6Adipose tissue inflammationLow-grade inflammationIndividual cell typesMacrophage infiltrationInflammatory cytokinesTissue inflammationGlucose disposalImmune cellsIL6 productionMouse modelChronic stateAdipose tissueMyeloid cellsTissue infiltrationReceptor αConditional expressionCell typesOxidative metabolismOpposite actionsPhysiological regulationEnergy expenditureCanonical modeInflammationSpecific cells
2019
Anti‐inflammatory effects of oestrogen mediate the sexual dimorphic response to lipid‐induced insulin resistance
Camporez JP, Lyu K, Goldberg EL, Zhang D, Cline GW, Jurczak MJ, Dixit VD, Petersen KF, Shulman GI. Anti‐inflammatory effects of oestrogen mediate the sexual dimorphic response to lipid‐induced insulin resistance. The Journal Of Physiology 2019, 597: 3885-3903. PMID: 31206703, PMCID: PMC6876753, DOI: 10.1113/jp277270.Peer-Reviewed Original ResearchConceptsObesity-induced insulin resistanceHigh-fat dietEctopic lipid contentWhite adipose tissue lipolysisInsulin resistanceAdipose tissue lipolysisMale miceInsulin sensitivityFemale miceInsulin-stimulated suppressionWAT inflammationTissue lipolysisRodent studiesTumor necrosis factor αWhole-body insulin sensitivityLipid-induced insulin resistanceMetabolic homeostasisAge-matched menInterleukin-6 concentrationsSkeletal muscleAnti-inflammatory effectsType 2 diabetesInsulin-mediated suppressionSexual dimorphic responseNecrosis factor α
2015
A Role of the Inflammasome in the Low Storage Capacity of the Abdominal Subcutaneous Adipose Tissue in Obese Adolescents
Kursawe R, Dixit VD, Scherer PE, Santoro N, Narayan D, Gordillo R, Giannini C, Lopez X, Pierpont B, Nouws J, Shulman GI, Caprio S. A Role of the Inflammasome in the Low Storage Capacity of the Abdominal Subcutaneous Adipose Tissue in Obese Adolescents. Diabetes 2015, 65: 610-618. PMID: 26718495, PMCID: PMC4764142, DOI: 10.2337/db15-1478.Peer-Reviewed Original ResearchMeSH KeywordsAbdomenAcetyl-CoA CarboxylaseAdipogenesisAdiponectinAdolescentCarrier ProteinsCaspase 1ChildDown-RegulationFatty Acid Synthase, Type IFemaleGene Expression ProfilingGlucose Transporter Type 4HumansInflammasomesInsulin ResistanceInterleukin-1betaIntra-Abdominal FatLeptinLipogenesisLipoprotein LipaseMacrophagesMagnetic Resonance ImagingMaleNLR Family, Pyrin Domain-Containing 3 ProteinObesityPPAR gammaSirtuin 1Sterol Regulatory Element Binding Protein 1Subcutaneous FatToll-Like Receptor 4ConceptsVisceral adipose tissueObese adolescentsInsulin resistanceTissue inflammationNLRP3 inflammasomeAdipose tissueInnate immune cell sensorsAbdominal subcutaneous adipose tissueAbdominal adipose depotsAbdominal fat partitioningAdipogenesis/lipogenesisAdipose tissue inflammationProinflammatory cytokines interleukinInfiltration of macrophagesExpression of CASP1Subcutaneous adipose tissueInflammation markersSAT biopsiesIL-18Macrophage infiltrationVisceral fatCytokines interleukinSAT ratioInsulin sensitivityAdipose depotsMacrophage-specific de Novo Synthesis of Ceramide Is Dispensable for Inflammasome-driven Inflammation and Insulin Resistance in Obesity*
Camell CD, Nguyen KY, Jurczak MJ, Christian BE, Shulman GI, Shadel GS, Dixit VD. Macrophage-specific de Novo Synthesis of Ceramide Is Dispensable for Inflammasome-driven Inflammation and Insulin Resistance in Obesity*. Journal Of Biological Chemistry 2015, 290: 29402-29413. PMID: 26438821, PMCID: PMC4705943, DOI: 10.1074/jbc.m115.680199.Peer-Reviewed Original ResearchMeSH KeywordsAdipose TissueAnimalsBone Marrow CellsCarrier ProteinsCeramidesDiet, High-FatDisease Models, AnimalFatty AcidsFemaleInflammasomesInflammationInsulin ResistanceLipidsMacrophagesMaleMiceMice, TransgenicMitochondriaNLR Family, Pyrin Domain-Containing 3 ProteinObesityOxidative StressSerine C-PalmitoyltransferaseConceptsDe novo synthesisNovo synthesisOverexpression of catalaseDietary lipid overloadSynthesis machineryTissue homeostasisCell-specific deletionInflammasome activationAdipose tissue homeostasisNLRP3 inflammasome activationMyeloid cell-specific deletionMetabolic pathwaysCeramide synthesisAlternate metabolic pathwaysCaspase-1 cleavageEnergy homeostasisLipid overloadCeramideLipid metabolismInflammasome-dependent mannerOxidative stressDanger signalsFat diet-induced obesityHomeostasisFatty acids
2005
Reduced mitochondrial density and increased IRS-1 serine phosphorylation in muscle of insulin-resistant offspring of type 2 diabetic parents
Morino K, Petersen KF, Dufour S, Befroy D, Frattini J, Shatzkes N, Neschen S, White MF, Bilz S, Sono S, Pypaert M, Shulman GI. Reduced mitochondrial density and increased IRS-1 serine phosphorylation in muscle of insulin-resistant offspring of type 2 diabetic parents. Journal Of Clinical Investigation 2005, 115: 3587-3593. PMID: 16284649, PMCID: PMC1280967, DOI: 10.1172/jci25151.Peer-Reviewed Original ResearchMeSH KeywordsBiopsyBlood GlucoseBlotting, WesternBody Mass IndexBody WeightDiabetes Mellitus, Type 2DNA, MitochondrialFamily HealthFemaleGene Expression RegulationGlucose Clamp TechniqueGlucose Tolerance TestHumansHyperinsulinismImmunoprecipitationInsulinInsulin Receptor Substrate ProteinsInsulin ResistanceLipidsMaleMicroscopy, ElectronMicroscopy, Electron, TransmissionMitochondriaMusclesPhosphoproteinsPhosphorylationProtein Serine-Threonine KinasesReverse Transcriptase Polymerase Chain ReactionRNA, MessengerSerineSignal TransductionTime FactorsTranscription, GeneticTriglyceridesConceptsInsulin-resistant offspringIR offspringType 2 diabetesInsulin-stimulated muscle glucose uptakeType 2 diabetic parentsIntramyocellular lipid contentHyperinsulinemic-euglycemic clampMuscle glucose uptakeIRS-1 serine phosphorylationMuscle mitochondrial densityMitochondrial densityMuscle biopsy samplesSerine kinase cascadeInsulin-stimulated Akt activationDiabetic parentsInsulin resistanceControl subjectsBiopsy samplesGlucose uptakeLipid accumulationMitochondrial dysfunctionInsulin signalingAkt activationEarly defectsMuscle
2004
Impaired Mitochondrial Activity in the Insulin-Resistant Offspring of Patients with Type 2 Diabetes
Petersen KF, Dufour S, Befroy D, Garcia R, Shulman GI. Impaired Mitochondrial Activity in the Insulin-Resistant Offspring of Patients with Type 2 Diabetes. New England Journal Of Medicine 2004, 350: 664-671. PMID: 14960743, PMCID: PMC2995502, DOI: 10.1056/nejmoa031314.Peer-Reviewed Original ResearchMeSH KeywordsAdenosine TriphosphateAdipose TissueBlood GlucoseDiabetes Mellitus, Type 2Fatty AcidsFemaleGlucoseGlucose Clamp TechniqueGlucose Tolerance TestGlycerolHumansInsulinInsulin ResistanceLipolysisMagnetic Resonance SpectroscopyMaleMitochondriaMuscle, SkeletalOxidative PhosphorylationTriglyceridesConceptsInsulin-resistant offspringType 2 diabetesIntramyocellular lipid contentInsulin-sensitive control subjectsMagnetic resonance spectroscopy studyInsulin resistanceControl subjectsProton magnetic resonance spectroscopy studyHyperinsulinemic-euglycemic clamp studiesTumor necrosis factor alphaImpaired mitochondrial activityIntrahepatic triglyceride contentDevelopment of diabetesChildren of patientsInsulin-resistant subjectsNecrosis factor alphaSensitivity of liverInsulin-stimulated ratesFatty acid metabolismMitochondrial oxidative phosphorylation activityInterleukin-6Intramyocellular lipidsPlasma concentrationsFactor alphaClamp studies
2003
Mitochondrial Dysfunction in the Elderly: Possible Role in Insulin Resistance
Petersen KF, Befroy D, Dufour S, Dziura J, Ariyan C, Rothman DL, DiPietro L, Cline GW, Shulman GI. Mitochondrial Dysfunction in the Elderly: Possible Role in Insulin Resistance. Science 2003, 300: 1140-1142. PMID: 12750520, PMCID: PMC3004429, DOI: 10.1126/science.1082889.Peer-Reviewed Original ResearchMeSH KeywordsAdipose TissueAdolescentAdultAgedAged, 80 and overAgingBlood GlucoseBody Mass IndexFemaleHumansInsulinInsulin ResistanceLiverMaleMiddle AgedMitochondriaMitochondrial DiseasesMuscle, SkeletalNuclear Magnetic Resonance, BiomolecularOxidation-ReductionOxygen ConsumptionPhosphorylationTriglyceridesConceptsInsulin resistanceInsulin-stimulated muscle glucose metabolismType 2 diabetesMuscle glucose metabolismLean body massElderly study participantsAge-associated declineMitochondrial function contributesFat massFat accumulationGlucose metabolismYoung controlsStudy participantsLiver tissueFunction contributesMitochondrial dysfunctionYounger participantsPossible roleMitochondrial oxidativeBody massMagnetic resonance spectroscopyParticipantsDiabetesDysfunctionPathogenesis
2001
Effect of triiodothyronine on mitochondrial energy coupling in human skeletal muscle
Lebon V, Dufour S, Petersen K, Ren J, Jucker B, Slezak L, Cline G, Rothman D, Shulman G. Effect of triiodothyronine on mitochondrial energy coupling in human skeletal muscle. Journal Of Clinical Investigation 2001, 108: 733-737. PMID: 11544279, PMCID: PMC209375, DOI: 10.1172/jci11775.Peer-Reviewed Original ResearchStimulating Effects of Low-Dose Fructose on Insulin-Stimulated Hepatic Glycogen Synthesis in Humans
Petersen K, Laurent D, Yu C, Cline G, Shulman G. Stimulating Effects of Low-Dose Fructose on Insulin-Stimulated Hepatic Glycogen Synthesis in Humans. Diabetes 2001, 50: 1263-1268. PMID: 11375325, DOI: 10.2337/diabetes.50.6.1263.Peer-Reviewed Original ResearchConceptsNet hepatic glycogen synthesisHepatic glycogen synthesisGlycogen synthesisSynthase fluxInfusion of fructoseLow-dose infusionType 2 diabetesEuglycemic hyperinsulinemic conditionsPotential therapeutic valueHepatic glycogen metabolismThreefold increaseFructose studiesEuglycemic hyperinsulinemiaHyperinsulinemic conditionsFructose infusionControl studyTherapeutic valueInfusionType 1Glucokinase activityGlycogen metabolismIndirect pathwaysStimulating effectInsulinStimulationInsulin Resistance and a Diabetes Mellitus-Like Syndrome in Mice Lacking the Protein Kinase Akt2 (PKBβ)
Cho H, Mu J, Kim J, Thorvaldsen J, Chu Q, Crenshaw E, Kaestner K, Bartolomei M, Shulman G, Birnbaum M. Insulin Resistance and a Diabetes Mellitus-Like Syndrome in Mice Lacking the Protein Kinase Akt2 (PKBβ). Science 2001, 292: 1728-1731. PMID: 11387480, DOI: 10.1126/science.292.5522.1728.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsBlood GlucoseDeoxyglucoseDiabetes Mellitus, Type 2FemaleGene TargetingGlucoseGlucose Clamp TechniqueGlucose Tolerance TestHomeostasisInsulinInsulin ResistanceIslets of LangerhansLiverMaleMiceMice, Inbred C57BLMice, TransgenicMuscle, SkeletalProtein Serine-Threonine KinasesProto-Oncogene ProteinsProto-Oncogene Proteins c-aktSignal TransductionConceptsSerine-threonine protein kinase AktProtein kinase Akt2Protein kinase AktProtein kinase B.Activation of phosphatidylinositolEssential genesKinase Akt2Kinase AktAbility of insulinGlucose homeostasisNormal glucose homeostasisAkt2Critical initial stepEarly eventsSkeletal muscleHomeostasisInsulin actionMice LackingInsulin responsivenessInitial stepActivationInsulin resistancePhosphatidylinositolBlood glucoseGenesContribution of net hepatic glycogen synthesis to disposal of an oral glucose load in humans
Petersen K, Cline G, Gerard D, Magnusson I, Rothman D, Shulman G. Contribution of net hepatic glycogen synthesis to disposal of an oral glucose load in humans. Metabolism 2001, 50: 598-601. PMID: 11319724, DOI: 10.1053/meta.2001.22561.Peer-Reviewed Original ResearchConceptsHepatic glycogen synthesisOral glucose loadGlucose loadMagnetic resonance imagingLiver glycogen synthesisNet hepatic glycogen synthesisLiver volumeGlycogen synthesisWhole-body glucose disposalGlycogen contentHepatic glycogen concentrationIngestion of glucoseLiver glycogen contentHepatic glycogen contentIdentical glucose loadHepatic UDP-glucoseGlucose disposalGroup 2Group 1Direct pathwayResonance imagingGlycogen concentrationMean maximum rateLiverIngestionAdipose-selective targeting of the GLUT4 gene impairs insulin action in muscle and liver
Abel E, Peroni O, Kim J, Kim Y, Boss O, Hadro E, Minnemann T, Shulman G, Kahn B. Adipose-selective targeting of the GLUT4 gene impairs insulin action in muscle and liver. Nature 2001, 409: 729-733. PMID: 11217863, DOI: 10.1038/35055575.Peer-Reviewed Original ResearchConceptsInsulin-stimulated glucose uptakeType 2 diabetesInsulin resistanceGlucose uptakeAdipose tissueGLUT4 expressionInsulin-resistant statesDownregulation of GLUT4Glucose intoleranceGlucose transportAdipose massIntracellular storage sitesGlucose homeostasisInsulin actionDiabetesPhosphoinositide-3-OH kinaseImpaired activationSkeletal muscleMuscleMicePlasma membrane4Early defectsLiverMain siteAdipocytes