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
2013
Targeting 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 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 treatment
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 models
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