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1 대한내과학회지 : 제 77 권제 2 호 2009 종설 (Review) 인슐린저항성의발생기전 한국마우스대사질환특화센타, 이길여암당뇨연구원, 가천의과학대학교 최철수 Pathogenesis of insulin resistance Cheol Soo Choi, M.D., Ph.D. Korea Mouse Metabolic Phenotyping Center, Lee Gil Ya Cancer and Diabetes Institute, Gachon University of Medicine and Science, Inchon, Korea 인슐린저항성 (Insulin resistance) 이란? 인슐린은당질, 지질및단백질등에너지대사를총체적으로조절하는가장중요한생체호르몬으로성장및전해질 (potassium) 조절에도관여하는데인슐린저항성 (insulin resistance) 은생리적인슐린농도에서이러한인슐린작용 ( 인슐린감수성 : insulin sensitivity) 이정상보다저하된 metabolic state 로정의할수있다. 그러나생체에서인슐린저항성을정확히간략하게정의하기는쉽지않다. 인슐린저항성상태라도모든인슐린작용이동시에같은정도로감소하는것도아니고, 신장에서염분저류및간에서의지방산신합성과같은기능은저하되지않고인슐린저항성에동반되는고인슐린혈증에의해오히려증가됨으로인슐린저항성관련대사질환의병인에는인슐린작용중저하된기능과고인슐린혈증에의해증가되는기능이모두함께관여하는것으로이해되고있기때문이다. 그러나인슐린작용중당질및지질대사에대한작용이감소된상태가대사성질환의발병과깊은연관성을나타내고비만및고지방식이에의한인슐린저항성초기부터관찰됨으로이를일반적으로인슐린저항성이라한다 1-3). 좀더구체적으로인슐린은췌장베타세포에서식후분비되어근육으로포도당섭취 (glucose uptake) 를촉진하거 나간에서포도당생성 (hepatic glucose output, HGO) 을억제하여혈당을조절하고, 지방조직에서지방산분해 (lipolysis) 를억제하여섭취된에너지를저장하는데인슐린저항성은인슐린이부족하지않은상태에서이러한인슐린작용이감소된상태를의미한다 1-3). 당질대사에있어서인슐린작용 (Insulin actions on glucose metabolism) 공복상태에서체내포도당이용의약 50% 는뇌에서사용되는데이를위해혈당은주로간의포도당생성 (HGO) 에의해유지되며, 포도당생성은간에저장된당원이분해 (glycogenolysis) 되거나포도당신생 (gluconeogenesis) 에의해유지된다 1-4). 6~12시간의공복까지는당원분해 (glycogenolysis) 와포도당신생과정 (gluconeogenesis) 이포도당생성에각각 50% 정도관여되나공복시간이길어지면포도당신생과정이포도당생성에더욱중요한역할을한다 1-4). 한편식후소화관에서음식물로부터흡수된포도당에의해혈당이증가하면췌장 β세포에서인슐린이분비되고, 분비된인슐린은근육으로포도당의흡수 (muscle glucose uptake) 를촉진한다. 또한인슐린은간의포도당흡수에도일부관여하지만주로간의포 * This study was supported by a grant of the Korea Healthcare technology R&D Project, Ministry for Health, Welfare & Family Affairs, Republic of Korea. (A084651)

- The Korean Journal of Medicine: Vol. 77, No. 2, 2009 - 도당생성을억제한다. 따라서인슐린은간에서포도당생성을억제하고근육을포함한말초조직으로포도당흡수를촉진하여혈중포도당농도를낮춘다 ( 그림 1). 간과근육으로흡수된포도당의대부분은당원으로저장되거나해당작용 (glycolysis) 을거쳐대사된다 1-4).

인슐린수용체 (insulin receptor) 에인슐린이결합한후 docking protein인 insulin receptor substrate 1, 2 (IRS1, IRS2) 의 tyrosine 인산화가증가하고, 이어서인산화된 IRSs 에 SH2 domain 을가지는단백질 (PI3K, Grb2, SHP2 등 ) 이결합하여활성화된다 6).

2 - The Korean Journal of Medicine: Vol. 77, No. 2, 도당생성을억제한다. 따라서인슐린은간에서포도당생성을억제하고근육을포함한말초조직으로포도당흡수를촉진하여혈중포도당농도를낮춘다 ( 그림 1). 간과근육으로흡수된포도당의대부분은당원으로저장되거나해당작용 (glycolysis) 을거쳐대사된다 1-4). 말초조직의세포내포도당흡수의속도조절단계는 glucose transporter 4 (GLUT4) 에의한세포내포도당유입과정이며이과정은인슐린신호전달계에의해주로조절된다 5). 인슐린수용체 (insulin receptor) 에인슐린이결합한후 docking protein인 insulin receptor substrate 1, 2 (IRS1, IRS2) 의 tyrosine 인산화가증가하고, 이어서인산화된 IRSs 에 SH2 domain 을가지는단백질 (PI3K, Grb2, SHP2 등 ) 이결합하여활성화된다 6). 근육에서는 PI3K에의해활성화된 Akt와 apkcs 에의해 GLUT4가 cytoplasmic pool에서 plasma membrane 으로이동하여인슐린자극에의한포도당유입을매개하고, 간에서는 PI3K에의해활성화된 Akt에의해당원분해와포도당신생을억제하여포도당의생성을억제하는것으로알려져있다 6). 대표적인인슐린감수성조직은근육, 간및지방조직인데, 인슐린작용에의한포도당대사는정량적인면에서주로근육과간에서일어난다 1). 따라서근육과간의포도당대사의직접적인변화없이는전신의포도당대사에서정량적으로영향을주기는어려우므로근육및간의인슐린저항성이전신의인슐린저항성을정량적으로결정한다고할수있다. 또한인슐린은지방조직에서지방분해를억제하고간및지방조직에서지방산신합성 (de novo lipogenesis) 을촉진한다. 인슐린저항성과제 2 형당뇨병및대사증후군과의관계 소로보이지만많은다양한원인에의한질환군이다. 이중제2형당뇨병의발생과가장밀접한관계를보이는비만및고지방식이에의한내당능장애환자에서흔히발견되는인슐린저항성의경우췌장베타세포에서인슐린분비능이보상적으로증가 (hyperinsulinemia) 되어있는상태에서는정상혈당을유지하지만인슐린분비능이인슐린저항성을극복할수없을경우혈당의상승과함께제2형당뇨병이발생하는것으로이해되고있다. 즉, 인슐린저항성은제2형당뇨병환자의대부분에서특징적이고공통적으로관찰되며 1-3), 제2형당뇨병환자의당뇨병이발병하지않은자식에서이미인슐린저항성을보이는경우가있고 7), 전향적연구에서인슐린저항성이제2형당뇨병발생의가장강력한예측인자이며 8), 인슐린저항성을호전시킴으로당뇨병발병을예방할수있다는연구결과 9) 를근거로제2형당뇨병의대부분을차지하는비만및고지방식이관련당뇨병에서는일반적으로인슐린저항성이선행하는일차적인원인으로생각되고있다. 또한인슐린저항성에대해보상적으로인슐린분비능이증가되는내당능장애상태에도혈당의상승을억제하여당뇨병발생은억제하지만다른심혈관질환의발생위험을증가시키므로인슐린저항성은제2형당뇨병의가장중요한선행요인인동시에대사증후군 (metabolic syndrome) 발생의핵심인자로생각되고있다 ( 그림 2) 10-13). 대사증후군은각각의질환을단일질병으로생각하지않고, 공통적인원인에의해발병할수있는하나의질환군으로묶어서생각하는개념이지만대사증후군의구성요소도다양하며새로운요소들이지속적으로밝혀지고있어대사증후군의병인을한가지요인으로설명하기란쉽지않다. 그러나인슐린저항성은대사성증후군의구성요소중가장흔히발견되고또대부분 인슐린저항성은제2형당뇨병의병인연구로개념및기전연구가시작되었다. 제2형당뇨병은고혈당을공통적요 Figure 1. Insulin actions on glucose metabolism. Figure 2. Insulin resistance plays a major role in the pathogenesis of type 2 diabetes and metabolic syndrome

3 - Cheol Soo Choi. Pathogenesis of insulin resistance - 의다른요소의발생과기전적으로밀접한상관관계를보여비만과함께대사성증후군의근본적인원인으로제시되고있다 10-13). 인슐린저항성이대사증후군의이상지질혈증및고혈압발생에관여하는기전을요약하면인슐린저항성및그와동반되는고인슐린혈증상태에서지방조직에서유리지방산의분해가상대적으로증가되어간으로유리지방산의유입이증가되면간에서지방합성및 Very Low Density Lipoprotein (VLDL) 의생성이증가되고또한지방조직에서 lipoprotein lipase를활성화시키는인슐린의작용에저항성이생겨혈중중성지방이증가될수있다. 혈중중성지방의증가에의한 cholesterol ester transfer protein의활성화로 HDL과 LDL에서 VLDL로콜레스테롤이이동하고역으로 VLDL의중성지방은 HDL과 LDL로이동하여중성지방이많아진 HDL 및 LDL이생기고이들은또다른중성지방분해효소인 hepatic lipase 의작용에의해분해되거나작아져혈중 HDL-C 농도는감소하고 small dense LDL 등은증가하는것으로설명할수있다 13). 또한인슐린저항성은교감신경계의활성화및인슐린에의한혈관내피세포의 Nitric Oxide 생성의장애와밀접한관계를보이고, 고인슐린혈증은신장에서염분저류및세포내 free cytosolic Ca 2+ 농도를증가시켜고혈압발생에관여하는것으로생각되고있다 13). 인슐린저항성발생기전 1. 조직의지방축적과인슐린저항성최근폭발적인증가를보이는제2형당뇨병및대사증후군은비만인구의증가와밀접한상관관계를보이며인슐린저항성을특징적으로나타낸다. 그러나지방조직의분화장애에의해지방조직의절대적감소를보이는 lipodystrophy 환자및마우스모델에서비만과반대의형질 (phenotype) 을보이지만전신비만환자보다도심한인슐린저항성을보인다 3,14). 이는에너지를지방으로축적할수있는지방조직의절대적부족으로섭취된에너지가포도당대사에정량적으로중요한간과근육에지방으로저장됨으로써더욱심한인슐린저항성이나타난다고보고되었다 3,14). lipodystrophy 마우스모델에지방조직을이식한경우 15) 와식이조절에의해식사량을감소시킨비만환자연구 16) 에서간과근육의지방축적이감소되었고, 더불어인슐린저항성이현저히호전되었다. 또한근육과간에특이적인지단백질분해효소 (lipoprotein lipase, LPL) 과발현마우스에서이들장기에선택적으 로지방축적을유도하였을때이들조직에인슐린저항성이나타났으며 17), 근육특이적인 LPL knock-out (KO) 마우스에서는근육의지방축적을예방하여고지방식이에의한인슐린저항성을현저히호전시켰다 18). 또한핵자기공명분광기법으로근육에축적된지방중세포내와세포외의지방을정량적으로측정하면세포내지방축적이인슐린저항성과가장밀접한관계를나타낸다 19). 이러한결과는비만에의한인슐린저항성의발생은전신비만보다는포도당대사에중요한근육과간의지방축적이직접적인원인이며조직에축적된지방중세포내지방축적이더욱중요한요인임을시사한다 ( 그림 3). 근육및간에축적된지방중대부분을차지하는중성지방은화학적으로비활성형태를취하고또중성지방합성의마지막단계인 diacylglycerol acyltransferase 1 (DGAT1) 을근육과간에과발현시켰을때중성지방은증가하지만인슐린저항성과는상관관계를나타내지않아축적된지방중대부분을차지하는중성지방보다는생리활성물질로서역할을하는지질대사체가인슐린신호전달계를억제하여인슐린저항성의발생에관여하는것으로생각되고있다 3,20-22). 이러한지질대사체로는중성지방경로의 long-chain acyl CoA, Lysophosphatidic acid, Phosphatidic acid, Diacylglycerol (DAG) 과스핑고지질계의 Ceramide 및 GM3, 인지질경로의 lysophosphatidylcholine 등이거론되고있다 20-22). 그외에도많은생리활성지질대사체가존재함으로새로운지질대사체가인슐린저항성발생을유도할가능성은충분하다. 이중가장많이연구된가설로조직에서유리지방산의이용증가로근육과간의 Diacylglycerol이증가하고이것이이들조직의 novel PKCs ( 근육 : PKCθ, 간 : PKCε), c-jun-n-terminal kinase (JNK), IkB kinase-β (IKK-β) 등을활성화시키고, 활성화된 serine/ threonine kinases 에의해 IRS1 & 2의 serine phosphorylation이증가하고 tyrosine phosphorylation은감소하여결국 PI3K 및 Akt의활성을감소시키므로서근육에서는 GLUT4에매개되는포도당유입이감소되고간에서는 HGO가억제되지않아인슐린저항성이발생한다는가설이제시되었다 3,20). 또한세포막을구성하는대표적인지질성분중하나인세라마이드는 palmitic acid로부터새로이합성될뿐만아니라 inflammation에동반되어 TNFα 에의해 sphingomyelinase가활성화되어 sphingomyeline에서도생성되어 protein phosphatase 2를활성화하여 Akt dephosphorylation을촉진하고, JNK1및 IKKβ 를활성화하여 IRS1 & 2의 serine phosphorylation을증가시켜포화지방산, TNFα 및 glucocorticoid에의한인슐린저항성을매

- 대한내과학회지 : 제 77 권제 2 호통권제 588 호 2009 - Figure 3. The potential mechanism of fat accumulation in the development of skeletal muscle insulin resistance. 개하는것으로알려지고있다 21,23,24).

4 - 대한내과학회지 : 제 77 권제 2 호통권제 588 호 Figure 3. The potential mechanism of fat accumulation in the development of skeletal muscle insulin resistance. 개하는것으로알려지고있다 21,23,24). 비만및고지방식이에서간과근육의세포내지방축적은지방산섭취 ( 유입 ), 합성의증가및지방산산화의감소에의해결정될수있으나, 지방축적에대한이들세가지경로의중요도는생리적조건과조직마다다른영향을나타내는데, 예를들어전신비만및 lipodystrophy 환자에서는간과근육에지방유입및합성의증가에의해서지방축적이증가한다면 16), 비만하지않은노인및인슐린저항성환자에서는미토콘드리아에서지방산산화의감소가지방축적의주된원인일가능성이제시되었다 25,26). 2. 염증반응 (Inflammation) 가설비만및고지방식이섭취시간, 근육조직의지방축적과함께지방조직 (adipose tissue) 의염증반응이동반된다. 비만과정에서지방조직을중심으로대식세포 (macrophage) 가침착하고, 활성화된대식세포와지방세포에서 inflammatory cytokine의분비가증가하여비만에동반된인슐린저항성을유발한다는가설이제기되고있다 27,28). 그러나이러한기전에의해인슐린저항성이유발되기위해서는비만조직으로부터생성된 inflammatory cytokine 이포도당대사에정량적으로중요한간과근육까지고농도로도달하여야가능하다. 왜냐하면지방조직의포도당섭취율은근육에비해약 20분이 1수준으로지방조직의국소염증반응으로지방조직에대한인 슐린저항성이발생하여포도당섭취가감소하여도간과근육에서포도당대사에영향이없으면전신의인슐린저항성및포도당대사에정량적으로영향을주기어렵기때문이다. 그러나 TNFα 나 IL-6 등대표적인 inflammatory cytokine 은인슐린저항성을보이는사람및동물모델의혈액에서혈중농도의증가를보이는경우가드물고 29-31), 이러한 inflammatory cytokine을고농도로주입한실험에서만간의인슐린저항성이발생한다는보고 32) 가있어지방조직의 inflammation이생리적조건에서도간과근육의인슐린저항성발생에유의하게기여하는지는아직분명하지않다. 더구나최근대표적인 inflammatory cytokine인 IL-6이오히려인슐린감수성을증가시킨다는연구결과들이나오고있다 33,34). 그러나근육및간의지방축적과함께이들조직에서염증반응의 signaling intermediate인 IKK-β, JNK1, suppressor of cytokine signaling 3 (SOCS3) 의활성이증가된다는연구결과 35-37) 로미루어볼때근육및간조직자체의지방축적에의해유도된염증반응이이들조직의인슐린저항성발생에직접영향을미칠수는있으리라생각되고있다. 따라서지방에의한인슐린저항성발생의초기단계에서근육및간조직내지방축적에따른염증반응의역할을배제할수는없지만비만에동반된염증반응은인슐린저항성발생에선행하는일차적원인이기보다는조직의지방축적에동반되어인슐린저항성을더욱악화시킬수있는추가요인으로생각된다

5 - 최철수. 인슐린저항성의발생기전 - Figure 4. Therapeutic targets for fat-induced insulin resistance by reducing fat synthesis and increasing fat oxidation. ACC, acetyl-coa carboxylase; DGAT, diacylglycerol acyltransferase; UCP3, uncoupling protein 3; PPARδ, Peroxisome proliferator-activated receptor δ. 제 2 형당뇨병및대사증후군의예방과치료를위한인슐린저항성치료전략 많은국내외제약회사의당뇨병치료제의개발과향후개발예정에도불구하고최근대규모역학연구에서 20년뒤전세계당뇨병환자의유병률이오히려 2배로증가할것이라고예측하고있다 38). 이는현재사용중이고, 개발예정인당뇨병치료제가제2형당뇨병발생의선행원인인인슐린저항성보다베타세포에서인슐린분비능을타깃으로하는것이주원인으로생각되고있다. 또한현재대사증후군의치료는고혈압, 이상지질혈증, 당뇨병등각질환별로이루어지고있으며질병의예방및근본적인치료보다는상태의악화를막는유지요법에치중하고있다. 따라서막대한의료비의투여에도불구하고질병의유병률및질병에의한사망률이감소하지않고오히려급격히증가하고있는실정이다. 따라서인슐린저항성발생기전에근거한인슐린저항성치료전략은당뇨병및대사증후군의예방및치료에효율적인방법이될수있다. 비만및고지방식이에의한인슐린저항성발생에서인슐린신호전달계를억제하는 serine/threonine kinases 및이들의활성화에직접연관된특이지질대사체가아직완전히규명 되지는않았고, 염증반응이인슐린저항성발생에일부관여하는것으로생각되지만, 조직의지방축적이인슐린저항성발생의선행하는직접적인원인으로생각됨으로조직의지방축적감소가인슐린저항성의치료전략으로연구되고있다. 조직의지방축적을감소시키는방법중간및근육조직특이적지방섭취의억제는다른조직에지방축적및인슐린저항성을초래하고, 식이조절은조직의지방섭취및합성을억제하며, 운동은지방산화를촉진시킬수있지만이들두방법은실제지속하기가어려운현실적단점이있다. 따라서지방합성 (de novo synthesis/re-esterification) 의억제및지방산화 (fat oxidation) 의증가를통해조직의지방축적을감소시키는것이효율적인치료타깃으로생각된다 ( 그림 4). 간은포도당대사및지질대사의핵심장기로지방산합성경로가활성화되어있어지방합성 (de novo synthesis/re-esterification) 의억제가지방축적을호전시키는효율적인방법으로생각된다. 유전자기능및치료타깃으로의평가를위하여유전자조작마우스 (Genetically engineered mouse, GEM) 를가지고연구하는것이필수적이며현재보편화되어있는기법이나 GEM를생산하는데많은비용과시간이소모되는제한점이있다. 그래서간을타깃으로한유전자의생체기능연구에서 GEM을이용하는연구방법의대안으로생체 RNAi

6 - The Korean Journal of Medicine: Vol. 77, No. 2, 기법이최근제시되었다. 생체주입된 RNAi는대부분간으로유입되고근육, 뇌, 심장등다른장기에흡수되는비율이비교적낮고간의타깃유전자를효율적으로억제할수있기때문에대사질환연구에좋은연구방법으로써이용될수있다. 간에서지방합성의처음과마지막단계인 acetyl-coa carboxylase 1&2 (ACC1&2) 및 diacylglycerol acyltransferase 2 (DGAT2) 를각각 antisense oligonucleotide (ASO) 를이용하여 in vivo에서이들유전자의 mrna 를선택적으로억제하였을때간의지방축적의감소및인슐린저항성의호전을보이고고지질혈증도호전되었다 39,40). 간과달리근육은체중의 30~40% 를차지하고포도당및지방산산화의대표적인장기이다. 따라서근육의지방축적을감소시키기위해서는지방산산화를촉진하는전략이가장효율적인방법으로생각되었다. 생체에너지소모에서정량적으로가장중요한미토콘드리아로지방산이동및산화를촉진시키기위해 ACC2의결핍 31) 및미토콘드리아에서에너지를열로발산하는 uncoupling protein 3 (UCP3) 의과발현 41) 마우스에서현저한비만예방효과와인슐린저항성호전이보고되었고, 또한미토콘드리아 biogenesis를증가시켜지방산산화를촉진하기위한 calcineurin 42) 과 PPARδ 43) 의근육특이적과발현마우스연구에서 type I muscle fiber 및미토콘드리아의현저한증가와함께고지방식이에의한비만및인슐린저항성이예방되었다. 따라서근육과간의지방축적을감소시켜인슐린저항성을예방및호전시키는것은당뇨병및대사증후군의효과적인예방및치료전략으로생각된다. REFERENCES 1) DeFronzo RA. Lilly lecture The triumvirate: beta-cell, muscle, liver: a collusion responsible for NIDDM. Diabetes 37: , ) DeFronzo RA, Bonadonna RC, Ferrannini E. Pathogenesis of NIDDM: a balanced overview. Diabetes Care 15: , ) Shulman GI. Cellular mechanisms of insulin resistance. J Clin Invest 106: , ) Salway JG. Metabolism at a glance. 3rd ed. Blackwell Science, ) Fink RI, Wallace P, Brechtel G, Olefsky JM. Evidence that glucose transport is rate limiting for in vivo glucose uptake. Metabolism 41: , ) Taniguchi CM, Emanuelli B, Kahn CR. Critical nodes in signaling pathways: insights into insulin action. Nat Rev Mol Cell Biol 7:85-96, ) Warram JH, Martin BC, Krolewski AS, Soeldner JS, Kahn CR. Slow glucose removal rate and hyperinsulinemia precede the development of type II diabetes in the offspring of diabetic parents. Ann Intern Med 113: , ) Lillioja S, Mott DM, Spraul M, Ferraro R, Foley JE, Ravussin E, Knowler WC, Bennett PH, Bogardus C. Insulin resistance and insulin secretory dysfunction as precursors of non-insulin-dependent diabetes mellitus: prospective studies of Pima Indians. N Engl J Med 329: , ) Buchanan TA, Xiang AH, Peters RK, Kjos SL, Marroquin A, Goico J, Ochoa C, Tan S, Berkowitz K, Hodis HN, Azen SP. Preservation of pancreatic beta-cell function and prevention of type 2 diabetes by pharmacological treatment of insulin resistance in high-risk hispanic women. Diabetes 51: , ) Reaven GM. Banting lecture 1988: role of insulin resistance in human disease. Diabetes 37: , ) Stern MP. Diabetes and cardiovascular disease: the common soil hypothesis. Diabetes 44: , ) Balkau B, Charles MA. Drivsholm T, Borch-Johnsen K, Wareham N, Yudkin JS, Morris R, Zavaroni I, van Dam R, Feskins E, Gabriel R, Diet M, Nilsson P, Hedblad B. Frequency of the WHO metabolic syndrome in European cohorts, and an alternative definition of an insulin resistance syndrome. Diabetes Metab 28: , ) Cornier MA, Dabelea D, Hernandez TL, Lindstrom RC, Steig AJ, Stob NR, van Pelt RE, Wang H, Eckel RH. The metabolic syndrome. Endocr Rev 29: , ) Danforth E Jr. Failure of adipocyte differentiation causes type II diabetes mellitus? Nat Genet 26:13, ) Gavrilova O, Marcus-Samuels B, Graham D, Kim JK, Shulman GI, Castle AL, Vinson C, Eckhaus M, Reitman ML. Surgical implantation of adipose tissue reverses diabetes in lipoatrophic mice. J Clin Invest 105: , ) Petersen KF, Oral EA, Dufour S, Befroy D, Ariyan C, Yu C, Cline GW, DePaoli AM, Taylor SI, Gorden P, Shulman GI. Leptin reverses insulin resistance and hepatic steatosis in patients with severe lipodystrophy. J Clin Invest 109: , ) Kim JK, Fillmore JJ, Chen Y, Yu C, Moore IK, Pypaert M, Lutz EP, Kako Y, Velez-Carrasco W, Goldberg IJ, Breslow JL, Shulman GI. Tissue-specific overexpression of lipoprotein lipase causes tissue-specific insulin resistance. Proc Natl Acad Sci U S A 98: , ) Wang H, Knaub LA, Jensen DR, Jung DY, Hong EG, Ko HJ, Coates AM, Goldberg IJ, de la Houssaye BA, Janssen RC, McCurdy CE, Rahman SM, Choi CS, Shulman GI, Kim JK, Kim JK, Friedman JE, Eckel RH. Skeletal muscle-specific deletion of lipoprotein lipase enhances insulin signaling in skeletal muscle but causes insulin resistance in liver and other tissues. Diabetes 58: ,

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<30315F D C1F6BBF3B0ADC1C25FC3D6C3B6BCF65FC0FAC0DAB1B3C1A4B9DDBFB52E687770> 대한내분비학회지 : 제 24 권제 2 호 2009 10.3803/jkes.2009.24.2.65 지상강좌 인슐린저항성의치료전략 한국마우스대사질환특화센타, 이길여암당뇨연구원, 가천의과학대학교 최철수 Potential Therapeutic Strategies for Fat Induced Insulin Resistance Cheol Soo Choi 1) Korea