2022
Distinct subcellular localisation of intramyocellular lipids and reduced PKCε/PKCθ activity preserve muscle insulin sensitivity in exercise-trained mice
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. Distinct subcellular localisation of intramyocellular lipids and reduced PKCε/PKCθ activity preserve muscle insulin sensitivity in exercise-trained mice. Diabetologia 2022, 66: 567-578. PMID: 36456864, PMCID: PMC11194860, DOI: 10.1007/s00125-022-05838-8.Peer-Reviewed Original ResearchConceptsProtein kinase CsSubcellular compartmentsDistinct subcellular localisationMuscle insulin sensitivityMultiple subcellular compartmentsInsulin receptor kinaseNovel protein kinase CsActivation of PKCεSubcellular localisationPKCθ translocationReceptor kinasePlasma membraneSubcellular distributionTriacylglycerol contentCrucial pathwaysIntramuscular triacylglycerol contentRC miceDiacylglycerolConclusions/interpretationThese resultsPKCεPM compartmentPhosphorylationMuscle triacylglycerol contentSkeletal muscleRecent findings
2021
Short-term overnutrition induces white adipose tissue insulin resistance through sn-1,2-diacylglycerol – PKCε – insulin receptorT1160 phosphorylation
Lyu K, Zhang D, Song J, Li X, Perry RJ, Samuel VT, Shulman GI. Short-term overnutrition induces white adipose tissue insulin resistance through sn-1,2-diacylglycerol – PKCε – insulin receptorT1160 phosphorylation. JCI Insight 2021, 6: e139946. PMID: 33411692, PMCID: PMC7934919, DOI: 10.1172/jci.insight.139946.Peer-Reviewed Original ResearchConceptsInsulin resistanceInsulin actionAdipose tissue insulin resistanceTissue insulin resistanceWT control miceHyperinsulinemic-euglycemic clampShort-term HFDTissue insulin actionAdipose tissue insulin actionDiet-fed ratsPotential therapeutic targetHFD feedingControl miceInsulin sensitivityTherapeutic targetLipolysis suppressionImpairs insulinHFDPKCε activationGlucose uptakeΕ activationMiceDiacylglycerol accumulationRecent evidenceProtein kinase C
2020
A Membrane-Bound Diacylglycerol Species Induces PKCϵ-Mediated Hepatic Insulin Resistance
Lyu K, Zhang Y, Zhang D, Kahn M, Ter Horst KW, Rodrigues MRS, Gaspar RC, Hirabara SM, Luukkonen PK, Lee S, Bhanot S, Rinehart J, Blume N, Rasch MG, Serlie MJ, Bogan JS, Cline GW, Samuel VT, Shulman GI. A Membrane-Bound Diacylglycerol Species Induces PKCϵ-Mediated Hepatic Insulin Resistance. Cell Metabolism 2020, 32: 654-664.e5. PMID: 32882164, PMCID: PMC7544641, DOI: 10.1016/j.cmet.2020.08.001.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsCell MembraneDiglyceridesHumansInsulin ResistanceLiverMalePhosphorylationProtein Kinase C-epsilonRatsRats, Sprague-DawleyReceptor, InsulinConceptsPlasma membraneEndoplasmic reticulumHigh-fat diet-induced hepatic insulin resistanceSubcellular fractionation methodInsulin receptor kinaseKey lipid speciesHepatic insulin resistanceDiet-induced hepatic insulin resistanceReceptor kinaseDiacylglycerol acyltransferase 2Molecular mechanismsAcute knockdownPhosphorylationLipid dropletsLipid speciesAcyltransferase 2KnockdownLiver-specific overexpressionDAG accumulationPKCϵDAG contentMembraneFractionation methodKinaseMitochondria