2019
Nonalcoholic Fatty Liver Disease, Insulin Resistance, and Ceramides
Samuel VT, Shulman GI. Nonalcoholic Fatty Liver Disease, Insulin Resistance, and Ceramides. New England Journal Of Medicine 2019, 381: 1866-1869. PMID: 31693811, DOI: 10.1056/nejmcibr1910023.Peer-Reviewed Original ResearchConceptsLiver diseaseInsulin resistanceNonalcoholic fatty liver diseaseNonalcoholic liver diseaseFatty liver diseaseType 2 diabetesDiseaseRecent studiesAtherosclerosisDiabetes
2017
Nonalcoholic Fatty Liver Disease as a Nexus of Metabolic and Hepatic Diseases
Samuel VT, Shulman GI. Nonalcoholic Fatty Liver Disease as a Nexus of Metabolic and Hepatic Diseases. Cell Metabolism 2017, 27: 22-41. PMID: 28867301, PMCID: PMC5762395, DOI: 10.1016/j.cmet.2017.08.002.Peer-Reviewed Original ResearchConceptsInsulin resistanceNonalcoholic fatty liver diseaseFatty liver diseasePeripheral insulin resistanceHepatic insulin resistanceNew pharmacological strategiesHepatic complicationsBariatric surgeryLiver diseaseInsulin-stimulated glycogen synthesisHepatic diseasePharmacological strategiesNAFLDReceptor activationHepatic glucoseLipid metabolismInsulin receptor activationWeight lossEnergy expenditureHepatic diacylglycerolsGlycogen synthesisDiseaseLipid synthesisFlux of substratesComplications
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
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 inhibitionThyroid hormone receptor-β agonists prevent hepatic steatosis in fat-fed rats but impair insulin sensitivity via discrete pathways
Vatner DF, Weismann D, Beddow SA, Kumashiro N, Erion DM, Liao XH, Grover GJ, Webb P, Phillips KJ, Weiss RE, Bogan JS, Baxter J, Shulman GI, Samuel VT. Thyroid hormone receptor-β agonists prevent hepatic steatosis in fat-fed rats but impair insulin sensitivity via discrete pathways. AJP Endocrinology And Metabolism 2013, 305: e89-e100. PMID: 23651850, PMCID: PMC3725564, DOI: 10.1152/ajpendo.00573.2012.Peer-Reviewed Original ResearchMeSH KeywordsAcetatesAnilidesAnimalsDietary FatsFatty LiverGene ExpressionGluconeogenesisGlucose Transporter Type 4HyperglycemiaHyperinsulinismInsulin ResistanceMaleMuscle, SkeletalNon-alcoholic Fatty Liver DiseasePhenolsRatsRats, Sprague-DawleySignal TransductionThyroid Hormone Receptors betaTriglyceridesConceptsEndogenous glucose productionHepatic insulin sensitivityInsulin sensitivityHepatic steatosisFat-fed ratsInsulin-stimulated peripheral glucose disposalTRβ agonistsInsulin-stimulated skeletal muscle glucose uptakePotent lipid-lowering drugsNonalcoholic fatty liver diseaseWhite adipose tissue lipolysisMale Sprague-Dawley ratsSkeletal muscle glucose uptakeGC-1 treatmentPeripheral glucose disposalFatty liver diseaseImpairs insulin sensitivityLipid-lowering drugsHepatic triglyceride contentAdipose tissue lipolysisMuscle glucose uptakeSprague-Dawley ratsHepatic insulin resistanceSkeletal muscle insulinPotential adverse effects
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
2007
Inhibition 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