2022
Deletion of Jazf1 gene causes early growth retardation and insulin resistance in mice
Lee H, Jang H, Li H, Samuel V, Dudek K, Osipovich A, Magnuson M, Sklar J, Shulman G. Deletion of Jazf1 gene causes early growth retardation and insulin resistance in mice. Proceedings Of The National Academy Of Sciences Of The United States Of America 2022, 119: e2213628119. PMID: 36442127, PMCID: PMC9894197, DOI: 10.1073/pnas.2213628119.Peer-Reviewed Original ResearchConceptsKO miceEarly growth retardationInsulin resistanceFat massGrowth retardationAge-matched wild-type miceHepatic nuclear factor 4 alphaGH-IGF-1 axisHigh-fat diet feedingKO liversHyperinsulinemic-euglycemic clamp techniquePlasma growth hormone concentrationInsulin-like growth factor-1Type 2 diabetesGrowth hormone concentrationsIGF-1 expressionWild-type miceLean body massMuscle insulin resistanceGrowth factor-1Nuclear factor 4 alphaInsulin sensitivityDiet feedingPlasma concentrationsHormone concentrations
2018
PEPCK1 Antisense Oligonucleotide Prevents Adiposity and Impairs Hepatic Glycogen Synthesis in High-Fat Male Fed Rats
Beddow SA, Gattu AK, Vatner DF, Paolella L, Alqarzaee A, Tashkandi N, Popov V, Church C, Rodeheffer M, Cline G, Geisler J, Bhanot S, Samuel VT. PEPCK1 Antisense Oligonucleotide Prevents Adiposity and Impairs Hepatic Glycogen Synthesis in High-Fat Male Fed Rats. Endocrinology 2018, 160: 205-219. PMID: 30445425, PMCID: PMC6307100, DOI: 10.1210/en.2018-00630.Peer-Reviewed Original ResearchMeSH KeywordsAdipose Tissue, WhiteAdiposityAnimalsDiabetes Mellitus, Type 2Diet, High-FatGlucokinaseHumansInsulinIntracellular Signaling Peptides and ProteinsLipogenesisLiverLiver GlycogenMaleMiceMice, Inbred C57BLOligonucleotides, AntisensePhosphoenolpyruvate Carboxykinase (GTP)RatsRats, Sprague-DawleyConceptsHepatic glycogen synthesisAdipose tissueAntisense oligonucleotideType 2 diabetes mellitusWhite adipose tissue massIncreased hepatic gluconeogenesisChow fed ratsHepatic insulin sensitivityMale Sprague-DawleyAdipose tissue massHepatic insulin resistanceWhite adipose tissueHepatic glucose productionDe novo lipogenesisHepatic glucokinase expressionControl antisense oligonucleotideGlycogen synthesisTranscription factor 3HFF ratsDiabetes mellitusHepatic steatosisInsulin resistanceHyperglycemic clampPlasma glucoseInsulin sensitivityPKCε 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
2015
Insulin-independent regulation of hepatic triglyceride synthesis by fatty acids
Vatner DF, Majumdar SK, Kumashiro N, Petersen MC, Rahimi Y, Gattu AK, Bears M, Camporez JP, Cline GW, Jurczak MJ, Samuel VT, Shulman GI. Insulin-independent regulation of hepatic triglyceride synthesis by fatty acids. Proceedings Of The National Academy Of Sciences Of The United States Of America 2015, 112: 1143-1148. PMID: 25564660, PMCID: PMC4313795, DOI: 10.1073/pnas.1423952112.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsDiabetes Mellitus, Type 2Enzyme InhibitorsInsulinInsulin ResistanceLiverPalmitic AcidRatsReceptor, InsulinSignal TransductionTriglycerides
2012
Mechanisms for Insulin Resistance: Common Threads and Missing Links
Samuel VT, Shulman GI. Mechanisms for Insulin Resistance: Common Threads and Missing Links. Cell 2012, 148: 852-871. PMID: 22385956, PMCID: PMC3294420, DOI: 10.1016/j.cell.2012.02.017.Peer-Reviewed Original ResearchConceptsUnfolded protein response pathwayProtein response pathwayInsulin resistanceFatty acid uptakeResponse pathwaysLipid metabolitesAcid uptakeSpecific lipid metabolitesEctopic lipid depositionImmune pathwaysPathwayImpaired insulinCommon final pathwayCellular changesComplex metabolic disorderSkeletal muscleMetabolic disordersLipid depositionFinal pathwayEnergy expenditureAccumulationEtiological pathwaysMetabolitesMissing linkResistance
2009
Fasting hyperglycemia is not associated with increased expression of PEPCK or G6Pc in patients with Type 2 Diabetes
Samuel VT, Beddow SA, Iwasaki T, Zhang XM, Chu X, Still CD, Gerhard GS, Shulman GI. Fasting hyperglycemia is not associated with increased expression of PEPCK or G6Pc in patients with Type 2 Diabetes. Proceedings Of The National Academy Of Sciences Of The United States Of America 2009, 106: 12121-12126. PMID: 19587243, PMCID: PMC2707270, DOI: 10.1073/pnas.0812547106.Peer-Reviewed Original ResearchMeSH KeywordsAdultAnimalsDiabetes Mellitus, Type 2Dietary FatsFastingFeeding BehaviorFemaleGene Expression Regulation, EnzymologicGluconeogenesisGlucose-6-PhosphataseHumansHyperglycemiaHyperinsulinismInsulin Infusion SystemsLiverMaleMiddle AgedPhosphoenolpyruvate Carboxykinase (ATP)RatsRats, Sprague-DawleyStreptozocinConceptsHigh-fat feedingEndogenous glucose productionHFF ratsExpression of PEPCKHepatic expressionType 2 diabetes mellitusBeta-cell compensationBeta-cell responseFirst rat modelPortal vein infusionLiver biopsy samplesHigher plasma glucosePhosphoenolpyruvate carboxykinaseBariatric surgeryT2DM patientsDiabetes mellitusInsulin resistancePlasma insulinPlasma glucosePortal infusionRat modelRodent modelsVein infusionHyperglycemiaKey gluconeogenic enzymes