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1 초대의말씀 결실의계절인 10월입니다. 삶의질향상에기여할 Metabolic Syndrome 에관한연구진흥의필요성과국내의연구현황과결과를소개할 "Metabolic Syndrome 연구포럼 " 을개최하게되어이에초대의말씀을전하고자합니다. 현재와같은무한국제경쟁시대에서국가의발전을위한과학기술의기여와새로운신산업성장동력으로서보건의료기술과의약및생물산업의도약을위한생명공학원천기술의개발이더욱요구되고있습니다. WHO는 위험에대한예방, 건강한생활에대한추구 라는보고서를통해대사성질환 ( 당뇨, 비만, 고혈압, 고지혈증등 ) 에의한장애가사망의핵심요인으로지적하고있을정도로대사성질환의문제점을중요하게다루고있습니다. 특히비만은이들대사성질환의발병요인으로소득과생활수준의향상에따른전염병으로선포될정도로선진국국가들이심각한문제로인식하여관련연구와예방을위한국가적사업으로추진하고있는실정입니다. 우리나라도선진국진입에따른고에너지식생활과안락한생활습관으로인한에너지대사의불균형으로인한비만과동아시아민족의공통적특징인당뇨등의고위험유병인자에의한대사상질환의유병률이급속히상승하고있는추세입니다. 또한고령화사회로의급속한전환으로일생의누적질환으로대사성질환의문제점은더욱중요하게대두되고있습니다. 따라서소득수준의상승과고령화사회에서필히직면할암등의수명연장을위한생명공학기술과난치병치료기술개발의범위에이어이러한대사성질환의문제점을인식하여관련연구및질병의개선에관한연구개발사업을국가차원에서육성해야할 21세기의전략과제로추진할필요성이제기되고있습니다. 이에한국생명공학연구원에서는현재 Metabolic Syndrome 에관련되어국내의대학, 연구소, 기업에서활발한연구활동을하고있는산학연의연구자들을모시고현재의연구상황과관련분야의연구진흥을위한토론의장을마련하기위해서 Metabolic Syndrome 연구포럼 을개최하고자합니다. 관련연구를수행하고계시는각계의연구자여러분들을초대하오니참석하시어최근의연구동향과연구진흥방향에대한논의에참여해주시기바랍니다 년 10 월 한국생명공학연구원장이상기 - 1 -

2 Metabolic Syndrome: Overview 가톨릭의대내분비대사내과손호영 현재까지의각종역학조사자료에의하면선진국혹은개발도상국가의국민전체중약 1/4이대사증후군 (Metabolic Syndrome) 을가지고있다고보고되고있다. 최근발표된 3 rd National Health and Nutrition Examination Survey (NHANES III) 결과에의하면 50세이상의미국인중약 44% 가 National Cholesterol Education Program (NCEP) 기준에의한대사증후군환자로밝혀졌다. 우리나라의경우도예외는아니어서본저자등이한농촌지역 40세이상의주민을대상으로시행한연구에서도 NCEP기준에따른대사증후군의연령보정유병률은 24.8% 였고, 남성과여성은각각 17.6%, 30.0% 였다. 대사증후군은임상적으로두가지주요질환과밀접한연관을가지는데그하나가죽상경화증으로인한각종심혈관질환으로써대사증후군의존재는관상동맥질환, 뇌혈관및말초혈관질환의발병위험을 2-3배증가시키는것으로알려져있다. 또한대사증후군은제 2형당뇨병의전구질환으로써도의미를가지는데일단당뇨병으로이환되면대사증후군과관련된심혈관질환의위험도가증폭된다. 최근대사증후군을진단하기위한여러가지진단기준들의유용성에대한논란과대사증후군의용어및임상적의의에대해서도의문이제기되고있다. 하지만학술적으로는최근 10여년간대사증후군이라는개념과여러진단기준이설정됨으로써많은역학조사가시행되고연구논문이발표되면서관련기초연구가활성화되었고임상적인면에서도환자들에게서로별개로여겨지던심혈관질환위험요인들의군집성 (clustering) 을설명할수있는근거가되었다는사실은부인할수없다. 그러나한편으로는현재까지대사증후군과그구성요인들에대한수많은연구들대부분이유병률과관련된단면조사를통해분석되었다는점에서향후대규모전향적임상연구에의한다양한연구결과들이제시되어야할것으로생각된다

3 대사증후군의발병기전 : 미토콘드리아기능이상의역할 울산의대내과학교실이기업 우리나라에서도서구화에따라비만이증가하면서대사증후군환자가급증하고있다. 대사증후군에속하는질환들의공통적발병기전에인슐린저항성이관여한다는것은잘알려진사실인데, 최근미토콘드리아기능이상이인슐린저항성및대사증후군발생에중요한역할을할것이라는가설이주목을받고있다. 미토콘드리아는산화적인산화과정을통하여 ATP를생산하는세포내소기관인데미토콘드리아기능이상에따라세포내지방산산화가감소하면지방산대사산물 (long chain fatty acyl CoA) 이축적되고이에따라인슐린저항성과세포내염증반응이증가되어당뇨병이나동맥경화증이발생한다고생각된다. 본교실에서는최근미토콘드리아호흡효소의조효소인 alpha-lipoic acid (ALA) 를비만동물에투여하였을때인슐린저항성의호전, 당뇨병발생의예방및혈관기능의호전이나타남을보고하였다 (Biochem Biophys Res Commun 332:885, 2005; Arterioscler Thromb Vasc Biol 25:2488, 2005). 이와같은효과는세포내에너지조절인자인 AMP activated kinase (AMPK) 의활성화에기인하였는데, 신기하게도뇌시상하부에서는 ALA가 AMPK를오히려감소시킴으로써식욕억제와체중감소효과를나타내었다 (Nature Med 10:727, 2004). Uncoupling protein 2 (UCP2) 는미토콘드리아내막에존재하는단백질인데 UCP2를혈관내피세포에과발현시켰을때활성산소생산및세포괴사가감소함을밝혀미토콘드리아기능이상이동맥경화증발생에관여함을규명하였다 (Circ Res 96:1200, 2005). Adiponectin은지방세포에서생산되는호르몬 (adipocytokine) 의하나로서인슐린저항성을감소시키고동맥경화증발생을억제하는것으로알려져있다. 혈액내 adiponectin은다른 adipocytokine과는달리지방조직의양이많은비만환자에서오히려감소되어있는데, 아직까지이러한현상이나타나는기전은밝혀지지않았다. Adiponectin은주로 크기가작은젊은지방세포에서생산되는것으로알려져있으며최근에는 adiponectin 생산을증가시키는것으로알려진 rosiglitazone 이지방세포에서 mitochondria 생산을증 - 3 -

4 가시킨다는사실이보고된바있다 (J Clin Invest 114:1281, 2004). 본연구팀에서는최근비만동물에서혈액내 adiponectin 농도가감소된것이지방조직미토콘드리아기능이감소된때문이라는것을세계최초로규명하였다. 이번연구에서는이외에도비만동물지방조직에서관찰되는미토콘드리아기능이상이 inos 활성화를통해 ER stress를증가시키며, 이를통해 adiponectin 생산감소를일으킴을확인하였다. 미토콘드리아기능이상, inos 활성화및 ER stress가인슐린저항성이나베타세포괴사, 당뇨합병증의원인으로각각거론되는점을감안할때이들을엮는새로운축이대사증후군의공통적원인기전이될지를연구하는것은매우흥미롭고도중요한연구과제가될것이다

5 과학기술정책과생명공학육성현황 과학기술부이석래 생명공학은정보통신이후국가성장의원동력의하나로그중요성이커지고있다. 리처드올리버도 The Coming Biotech Age (2000) 에서정보화시대이후생명공학의시대를예견하였고, 미국과학재단 (NSF) 의미래과학기술예측진단보고서인 Converging Technologies For Improving Human Performance 2002에서도정보통신이후에바이오와나노의시대를예측하고있다. 생명공학은고부가가치지식산업으로연구가산업으로직결되고, 기초연구의의존성이높고, 막대한연구개발비가소요되며, 사회적이해와지지가매우중요한특징을갖고있다. 세계각국도생명공학에대한투자를지속적으로강화하고있으며우리나라도지속적으로육성정책을펴고있다. 정부는 1983년생명공학육성법제정이후 1994년제1차생명공학육성기본계획을수립하여 2006년까지연평균투자증가율이 23% 에달하여 2006년에는 8,000억원에이르고있으며이후에도지속적으로지원을강화할예정이다

6 Drug Discovery Strategy of LGLS for Targeting Metabolic Diseases Soon Ha Kim * and Jong Sung Koh Drug Discovery & Early Development, Cardiovascular and Metabolic disease, LG Life Sciences, Ltd. / R&D Park, Daejeon, Korea Despite significant progress in understanding the mechanisms underlying the pathophysiology of metabolic diseases, relatively few drugs that improve the metabolic risk profile in patients are developed. Over 100 gene targets have been evaluated in multiple rodent and non-primate models of diabetes and obesity. Several of these targets are in late-stage preclinical or clinical pharmacology evaluation. The focus of LGLS metabolic disease program is to develop novel drugs that target diabetes and obesity. We have developed a rapid, high throughput capability for validating drug targets for diabetes and obesity in pre-clinical animal models. More recently, LG Life Sciences has started evaluating compounds for the treatment of diabetes and obesity and have obtained encouraging results. The first development compound, LC , an inhibitor of the target DPP IV enzyme, has demonstrated good profile of in vivo potency and safety in preclinical study and is expected to initiate clinical phase I for diabetic patients in Oct. Additional candidate compounds against diabetes and obesity are under development of preclinical stage. LG Life Sciences seeks alliances for discovery and development of small molecule drugs for the treatment of diabetes and obesity and other metabolic diseases as well as for the downstream of commercialization products. The prospective and therapeutic potential of anti-diabetes and anti-obesity drugs as well as the recent data obtained from LG Life Sciences will be presented and discussed this time

7 An Antidiabetic Agent, CKD-501 (PPAR α/γ Dual agonist) Jae Soo Shin 1, Young Min Kwon 1, In Chang Hwang 1, Chang-Kiu Moon 2, SungSook Lee 1, Hong Woo Lee 1, Soon Kil Ahn 1 1 Chong Kun Dang Research Institute, Chong Kun Dang Pharm., Chonan, Republic of Korea. 2 College of Pharmacy, Seoul National University, Seoul, Republic of Korea CKD-501 is a PPAR α/γ dual agonistic glitazone analog for the treatment of type 2 diabetes and associated dyslipidemia. Phase I clinical trial of CKD-501 has been completed in Korea. CKD-501 has been demonstrated to have insulin sensitizing, antihyperglycemic and antihyperlipidemic activities in diabetic animals. CKD-501 activated PPAR α/γ (EC 50 = 2500 and 1.1 nm, respectively) more potently than rosiglitazone (EC50 >10000 and 4.1 nm, respectively) in hppar transactivation assay using 293-T cells. CKD-501 increased 2-DOG uptake (EC 50 = 1.98 μm) markedly, triglyceride (TG) accumulation (EC 50 = 2.8 nm), expression of ap2, PPARγ, and GLUT-1 and 4,and translocation of GLUT-1 and 4 to plasma membrane in 3T3-L1 adipocytes. CKD-501 showed 3-fold more potent antidiabetic activities than rosiglitazone in type II diabetic animal models, whereas CKD-501 did not show any activity in streptozotocin-induced type I diabetic rats. In Zucker diabetic rats, CKD-501 (10 mg/kg) administered orally for 4 weeks, reduced significantly plasma glucose, insulin, TG, non-esterified fatty acid and total cholesterol levels by 32, 89, 65, 72 and 35%, respectively. Furthermore, CKD-501 increased the expression of ap2, PPARγ and GLUT-4, translocation of GLUT-4 to plasma membrane, 2-DOG uptake (143%), glucose oxidation (413%) and lipid synthesis (1000%) in adipose tissue. CKD-501 also increased glucose oxidation (73%), glycogen synthesis (64%) and glycolysis (394%) in soleus muscle. In KKAy and ob/ob mice, CKD-501 (10 mg/kg) not only decreased plasma glucose (52%, 29% respectively), insulin (84% and 75% respectively) and lipid levels, but also improved glucose metabolism in adipose tissue. The phase I clinical study was a double-blind, placebo controlled, randomized and parallel trial. In single dose study, five different single doses of 0.5, 1, 2, 4, 8 mg of - 7 -

8 tablets were administered in healthy volunteers and In multiple dose study, three doses of 1, 2, 4 mg/day of tablets were administered in healthy volunteers for 7 days. Maximum concentrations of CKD-501 were reached after 1-3 hours. Their half-lives were hours. The drug was well tolerated and the pharmacokinetic profile supported a once-daily administration for CKD

9 생체에너지대사조절기전연구 - 대사질환관련국가지정과제연구현황 울산의대서울아산병원박중열 본연구실에서는중추신경계 ( 시상하부 ) 와말초조직 ( 골격근, 지방조직, 간및혈관 ) 사이에이루어지는유기적에너지대사조절기전, 특히생체에너지대사조절물질중세포및생체에너지상태를감지하는 sensor의기능을가진 AMPK와영양소의산화에의해 ATP를생산하는세포내소기관인미토콘드리아의기능조절기전을규명함으로써생체에너지대사조절기전을규명하고있다. 상기목표를달성하기위하여 (1) 시상하부의생체에너지조절기전규명, (2) 미토콘드리아기능과인슐린저항성의관계및 (3) 생체에너지대사조절물질이동맥경화증발생에미치는영향에관한연구를진행하고있다. 1) 당뇨병에서시상하부식이섭취조절기전의이상규명 시상하부 AMPK의활성억제가당뇨병성다식증에미치는영향규명심한당뇨병을가진동물과사람에서는흔히다식증이동반된다. 지금까지이를매개하는세포내분자생물학적기전은잘밝혀져있지않다. 본연구에서는당뇨병동물모델에서혈중인슐린및렙틴의저하로인해시상하부 AMPK 활성이증가되어있고, 이를통해식욕조절신경펩타이드의발현이변함으로써다식증이발생함을밝혔다. 저혈당에대한신경내분비반응에있어시상하부 AMPK의역할저혈당은인슐린치료를받는당뇨병환자에있어피하기어려운부작용으로심할경우뇌손상및사망에이르는중요한문제이다. 시상하부신경세포에서어떤신호전달과정을거쳐저혈당을감지하고, 신경내분비반응을유발하는지구체적인분자생물학적기전은아직잘밝혀져있지않다. 본연구결과저혈당상태에서는시상하부 (PVN, VMH) 에서 AMPK가활성화되며, 이는저혈당회복에중요한신경내분비반응을매개하는데중요한역할을수행함을알수있었다. 특히 VMH에서의 AMPK 활성은초기저혈당상태에서혈당을올리는데중요한역할을하고, PVN의 AMPK 활성화는후기저혈당상태에서의회복에결정적인역할을수행함을확인하였다. 시상하부 AMPK가단지에너지만을감지하는효소가아니라생체에너지항상성및신경내분비반응조절에도중요한역할을함을처음으로제시하였다, - 9 -

10 2) Alpha-lipoic acid (ALA) 가당뇨병및혈관기능에미치는영향및기전규명 ALA가비만및당뇨병동물모델 (OLETF 쥐 ) 에서당뇨병발생에미치는영향본연구팀에서는이전의연구에서항산화제인 ALA의항비만효과를보고하였다. ALA의항비만효과뿐만아니라비만당뇨병모델쥐인 OLETF 쥐에게 ALA를투여하였을때대조군에비해당뇨병발생이유의하게감소하였다. 또한 ALA의투여는 OLETF 쥐에서나타나는췌장소도의파괴를억제하였으며, 골격근및췌장소도에서의지방축적을감소시켰다. 이러한결과는 ALA가지방축적억제효과를통해골격근에서는인슐린감수성을호전시키고췌장에서는베타세포의사멸을감소시켜당뇨병발생을억제함을보이고있다. ALA가 OLETF 쥐의골격근에서인슐린감수성에관여하는기전 ALA가 OLETF 쥐골격근에서인슐린감수성을호전시키는기전을알아보기위한연구를진행하였다. ALA를투여한쥐에서 AMPK의발현과활성도가증가하였으며지방산산화가증가됨을확인하였다. 이러한결과는당뇨병및비만동물모델에서 ALA가 AMPK 활성을통해골격근에서의지방산산화를증가시키고이를통해골격근에서의인슐린작용을향상시킴을보여주는것이다. ALA가 OLETF 쥐에서혈관기능에미치는영향혈관내피세포에지방질이침착되는것이비만환자에서의죽상경화증발생에있어중요한병태생리중하나일것으로생각되고있다. 이번연구에서는알파리포산이혈관내피세포에서 AMPK를활성화시켜비만동물모델에서나타나는혈관기능이상을회복시킬지여부를확인하고자하였다. 비만및당뇨병동물모델인 OLETF 쥐의경우대조군에비해혈관내피의존성혈관확장에장애가있었고내피세포사멸이증가된소견을보였다. 또한 OLETF 쥐의경우대조군에비해내피세포내중성지방및 lipid peroxide 가증가되어있었으며 nitric oxide (NO) 는감소되어있었다. OLETF 쥐에 ALA를투여하였을때혈관내피의존성혈관확장장애를호전시켰고내피세포사멸을억제하였다. 또한중성지방의축적과 lipid peroxide는감소시켰으며 NO는증가시켰다. 한편 OLETF 쥐의내피세포에서 AMPK 활성도가대조군에비해감소되어있었고 ALA 투여에의해 AMPK 활성도가증가하였다. 이러한결과는비만및당뇨병동물모델에서의혈관기능이상이 AMPK 활성감소에기인함을처음으로밝힌것이다. 3) FOXO1 에의한시상하부식이섭취조절기전을규명 시상하부는말초로부터전달되는에너지저장신호를분석함으로써섭식과에너

11 지대사를조절한다. 에너지저장신호중대표적인것은렙틴 (leptin) 과인슐린 (insulin) 인데, 이들두호르몬은섭식조절에관여하는신경펩타이드생산을조절함으로써섭식을조절한다. 하지만이들두호르몬에의한신경펩타이드의전사조절기전은아직잘이해되고있지않다. Forkhead transcriptional factor인 FOXO1 혹은 FKHR은세포의생존및사멸에중요한전사인자로알려져왔는데, 최근에는 FOXO1 이골격근, 지방조직, 간, 췌장베타세포등말초조직에서인슐린에의한전사조절작용을매개하는중요한전사조절인자임이밝혀짐으로써대사조절에있어서중요한전사인자로부각되고있다. 본연구에서 FOXO1을과발현시킨동물에서는먹이섭취와체중이증가하였고, 반대로 FOXO1 RNAi를주입한동물에서는먹이섭취와체중이감소하였다. 식후증가한렙틴과인슐린이 FOXO1을인산화시키고 FOXO1 단백량을감소시키는신호로작용하는지알기위하여인슐린과렙틴을직접뇌실내로투여하였을때 FOXO1의단백양은감소시키고 FOXO1의인산화를촉진시켰다. 또한, 렙틴과인슐린에의하여조절을받는대표적인신경펩타이드인 neuropeptide Y (NPY) 의전사조절에 FOXO1이직접적으로관여함을확인할수있었다. 상기연구결과는공복상태 ( 혈중렙틴과인슐린농도가낮은상태 ) 에서 FOXO1이 NPY 생산을자극하며, 식사후혈중렙틴과인슐린이상승하면 NPY 생산이감소시킴을보여줌으로써 FOXO1이시상하부에서렙틴과인슐린작용을매개하는중요한전사조절인자임을밝힌것이다. 4) UCP-2 과발현이혈관세포및기능에미치는영향 UCP-2 과발현이혈관내피세포사멸및혈관기능에미치는영향미토콘드리아에존재하는단백질인 uncoupling protein-2 (UCP-2) 가혈관기능에미치는영향을확인하기위하여혈관내피세포에과발현시켰을때혈관확장에관여하는 enos (endothelial nitric oxide synthase) 의 mrna 발현이증가되고혈관수축에관여하는 endothelin-1의발현은감소하였다. 또한 UCP-2는혈관내피세포에서 lysophosphatidylcholine 이나 linoleic acid에의해유발되는 ROS (reactive oxygen species) 증가, NF-κB 활성및세포사멸을억제하였으며 LPC에의한혈관내피의존성혈관확장장애를회복시켰다. 이결과는 UCP-2가혈관내피세포에서 ROS 생성을조절하는역할을하며혈관내피세포에서 UCP-2의발현을증가시키면동맥경화증의새로운치료법이될가능성을제시하였다. UCP-2 과발현이혈관평활근세포의 PAI-1 발현및증식, 이동에미치는영향혈관평활근세포에고농도의포도당과안지오텐신 II를처리시세포내산화스트레스및전사인자 AP-1, PAI-1 발현및, NADPH oxidase가활성화되었다. 뿐만아니라동맥경화증의발생지표인혈관평활근세포의증식및이주또한증가하였다. 하지만, UCP-2를혈관평활근세포에과발현하였을때이런변화들이현저하게억제되는것

12 을관찰할수있었다. 즉 UCP-2가혈관평활근세포의만성염증반응을억제하고이상증식을억제하여고혈압및당뇨병을동반한동맥경화증환자에서새로운치료제로사용될가능성을보여주었다. 5) PGC-1 이혈관세포사멸에미치는영향규명 PGC-1이혈관세포사멸에미치는영향혈관내피세포에 linoleic acid (LA) 를처리하였을경우, 세포내 ROS와세포사멸이증가하였으나, PGC-1를과발현한세포에서는이와같은증가가뚜렷이감소하였다. PGC-1는내피세포내지방산산화를증가시켰고, 중성지방축적을감소시켰으며, 미토콘드리아와세포질사이의 ADP/ATP 교환을관장하는 adenosine nucleotide translocator (ANT) 의기능을호전시켰다. ANT-1에대한 sirna를이용하여 ANT-1 발현을억제하였을경우 PGC-1의세포사멸, ROS, 지방산산화와막전위압에대한효과가상쇄되었다. 이상의결과는 PGC-1가 ANT 활성증가를통해혈관내피세포에서지방과부하에의해유발된세포사멸을예방할수있음을보인것이다. 6) 비만쥐에서 ALA 처리시 ADMA 에미치는영향규명 Asymmetric dimethylarginine (ADMA) 는내인성 nitric oxide synthase (NOS) 의억제물질로 nitric oxide (NO) 생성을방해하여혈관내피세포기능이상을초래하며, 심혈관위험성을높이는물질이다. ALA 투여시혈관내피세포배양액내의 ADMA 농도를감소시켰고, OLETF 쥐의혈장에서 ADMA 농도를유의하게감소시켰다. 또한 ALA 투여후혈관내피세포의 DDAH 활성도및 DDAH II promoter 활성도가증가하였다. 이에반해 STAT3 결합부위를변형시킨 DDAH II promoter를사용했을때 ALA에의한 promoter 활성화가상쇄되어 ALA에의한 DDAH II 유전자발현증가가 STAT3에의해매개됨을보여주었다. 이상의결과는 ALA가 DDAH II-ADMA system 에작용하여 NO 생성을조절함으로써혈관내피세포의기능을보호하고, 혈관내피세포기능이상과연관된각종심혈관질환의예방과치료에기여할가능성을시사한다. 7) 미토콘드리아기능과인슐린저항성과의관계규명 PPAR alpha와 PGC-1를통한지방산산화의증가 AMPK는세포내에너지상태를감지하는효소로서근육에서의포도당수송및지방산산화를증가시키는것으로알려져있다. AMPK에의한지방산산화에서기존에알려진 ACC/ malonyl CoA를통한지방산산화조절경로이외에다른전사조절기전이있을가능성에대한연구를진행하였다. 지방산대사에중요한역할을한다

13 고알려진 PPAR alpha 및미토콘드리아생성에중요한역할을하는 PGC-1이골격근세포에서 AICAR에의에그발현이증가하였으며, PPAR alpha sirna 및 PGC-1 sirna의과발현은 AICAR에의한지방산산화증가를억제시켰다. inos와인슐린감수성과의관계규명비만시나타나는골격근에서의인슐린저항성발생에 inducible nitric oxide synthase (inos) 가관여함이보고되었다. OLETF 쥐의골격근에서 inos의발현이대조군인 LETO 쥐에비해의미있게증가되었다. inos 억제제인 aminoguanidine 을 OLETF 쥐에게 3주간투여하였을때인슐린감수성의감소가대조군수준으로회복되었다. 이상의결과는비만동물모델에서활성화된 inos가골격근조직에서인슐린저항성을유발할가능성을보여주고있다. inos 발현증가가어떤기전을통하여인슐린저항성을유발하는지에대한실험을수행중이다. 8) 지방세포에서 adiponectin 생산에있어미토콘드리아의역할규명 체내잉여에너지를저장하는지방세포에도미토콘드리아가존재하며지방세포분화시미토콘드리아생산이증가됨이보고되었지만이세포에서미토콘드리아기능은아직까지명확하지않다. 한편, 과거오랫동안단순한에너지저장고로만여겨져왔던지방조직이능동적으로 adipocytokine을분비함으로써체내에너지항상성유지에중추적역할을한다는개념이최근대두되고있다. 다른 adipocytokine과는달리혈액내 adiponectin 양은지방조직의양이많은비만환자에서감소되어있는데, 아직까지이러한현상에대한정확한기전은밝혀져있지않다. 본연구는지방세포에있는미토콘드리아가 adiponectin 생산에필수적역할을할것이라는가설을증명하기위하여시행되었다. 인슐린감수성을증가시키는 thiazolidinedione을투여하였을때 3T3L1 지방세포에서미토콘드리아양이증가하면서 adiponectin 생산이증가하였다. 반대로미토콘드리아기능을억제하는여러물질은 adiponectin 생산을감소시켰다. 한편미토콘드리아생성을증가시키는 NRF-1을과발현시켰을때 adiponectin이증가하였다. 한편 3T3L1 세포를장기간배양하였을때 adiponectin 생산이저하되고미토콘드리아양이감소하는한편 inos발현과 endoplasmic reticulum (ER) stress가증가하였고 thiazolidinedione은이들을감소시켰다. inos 억제제는노화및미토콘드리아기능억제물질에의한 ER stress를감소시키는한편 adiponectin 생산을증가시켰고 ER stress를감소시키는 ORP150도 adiponectin 생산을증가시켰다. 이상의결과지방세포노화에따른미토콘드리아기능의저하가 inos 발현을유도함으로써 ER stress를유발하고이에따라 adiponectin 생산이감소함을밝혔다. 최근미토콘드리아기능이상, inos 과발현, ER stress가각각인슐린저항성의원인으로제시되었다

14 Adipocentric Regulation in Whole Body Energy Homeostasis and Metabolic Disorders Jiyoung Park, Yun Sok Lee, Woo Sik Kim, and Jae Bum Kim* Department of Biological Sciences, Seoul National University, Seoul, Korea During the past several decades, the incidence of obesity has significantly increased worldwide. Enormous efforts have been devoted to understand the molecular mechanisms underlying obesity and its related metabolic disorders such as type 2 diabetes, cardiovascular disease, atherosclerosis, and hypertension. It is now well-established that altered adipocyte metabolism in obese patients is closely associated with the induction of various metabolic stresses including hyperglycemia, hyperlipidemia, hyperinsulinemia, and chronic inflammation. However, it remains to be elucidated the cellular factor(s) which sense metabolic changes and/or initiate the pathological progression of obesity-induced metabolic disorders. In this presentation, my talk will be divided into two parts. In the first part, I will discuss novel roles of G6PD, a NADPH-generating enzyme, in adipocytes. Overexpression G6PD in fat cells provokes dysregulation of lipid metabolism an adipocytokine production and stimulates inflammatory signals to enhance crosstalks between adipocytes and macrophages in obesity, suggesting that G6PD as a novel target for treating metabolic disorders. In the second part, I will present our recent study with berberine, showing lipid lowering properties as well as anti-adipogenic effects. When berberine was administrated into obese and/or diabetic animal models, it exhibits beneficial effects on weight and lipid lowering. Finally, we demonstrate that berberine converges upon the AMPK/p38 MAPK/PPARgamma axis. Therefore, we believe that berberine would be an excellent lead compound to develop for anti-obesity and anti-diabetic drugs

15 Pharmacological Control of Mitochondrial Plasticity for the Treatment of Metabolic Syndrome Minho Shong Laboratory of Endocrine Cell Biology, National Research Laboratory Program, Department of Internal Medicine, Chungnam National University School of Medicine Emerging evidences support the potentially unifying hypothesis that the prominent features of metabolic syndrome and type 2 diabetes are caused by mitochondrial dysfunction. This loss of mitochondrial function predisposes to intramyocellular lipid accumulation, which provides the link with insulin resistance. Recent studies have found that the reduction in mitochondrial activity in the insulin-resistant offspring could be attributed to reduction in muscle mitochondrial content. Mitochondria exhibits remarkable adaptive capabilities in response to a number of physiological and pathophysiological conditions. The mitochondrial plasticity consists of two possible alterations increase in mitochondrial content and changes in mitochondrial compositions. The nicotinamide cofactors NAD(P)+ and NAD(P)H plays critical roles in energy metabolism. The level of NAD(P)+ and NAD(P)H determine the glucose metabolism, lipid synthesis and mitochondrial oxidative phosphorylation. The pharmacological increase of NAD(P)+/NAD(P)PH ratio induce strong activation of AMP kinases and mitochondrial fatty acid oxidation in vitro and in vivo. The most of phenotypes of metabolic syndrome for example, obesity, glucose intolerance, dyslipidemia, and fatty liver are reversed by pharmacological (βl) modulation of cytoplasmic NAD+/NADPH ratio. The mice treated with βl showed preferential induction of genes related to mitochondrial biogenesis, fatty acid oxidation and showed higher energy expenditure and increased content of mitochondria in liver and muscles. Here we provide the evidences that higher NAD(P)+/NAD(P)H ratio is a novel ways for the cure of metabolic syndromes including obesity by control of mitochondrial plasticity

16 The Orphan Nuclear Receptor DAX-1 Interacts with PPARγ and Represses Its Transactivation Hueng-Sik Choi Hormone Research Center, Chonnam National University, Gwangju, Republic of Korea DAX1 (NR0B1) is an atypical orphan nuclear receptor functions primarily as corepressor through heterodimeric interactions with other nuclear receptors. Peroxisome proliferator-activated receptor (PPAR) γ is a ligand-activated nuclear receptor that plays a key role in lipid metabolism and insulin sensitization, as well as in inflammation and cell proliferation. Herein, we examined a novel cross talk between DAX-1 and PPARγ. Transient transfection assay demonstrated that DAX-1 inhibited the transcriptional activity of PPARγ. Our in vitro interaction assays showed that DAX-1 physically interacted with PPARγ in ligand independent manner. Interaction domain mapping results indicated that the DBD/Hinge region of PPARγ is essential for the interaction with DAX-1. DAX-1 repressed the PPARγ transactivation as well as interaction through the competition with PGC-1α for the binding with PPARγ. Overall, our results suggest that DAX-1 acts as a novel corepressor of PPARγ and that may regulate the PPARγ-mediated cell differentiation

17 Mitochondrial Oxidative Dysfunction in the Diabetic Macrovascular Complication In-kyu Lee Dept of Int. Med., Kyungpook National University 1, School of Medicine, Daegu, Korea Increased oxidative stress in vascular cells has been implicated in the pathogenesis of atherosclerosis. The peroxisome proliferators-activated receptor-γ coactivator 1-α (PGC-1α) is a transcriptional coactivator identified as an upstream regulator of mitochondrial number and function. Several lines of evidence suggested that peroxisome proliferators-activated receptor-γ coactivator 1-α (PGC-1α) is an important regulator of intracellular ROS production. Reactive oxygen species (ROS) induces vascular inflammation via proinflammatory cytokine/nf-κb pathway. However, no study has examined the effect of PGC-1α on this process. Here we investigated the effect of PGC-1α on vascular inflammatory molecule expression and redox-sensitive transcription factor NF-κB activity in vascular cells. PGC-1α is expressed in human aortic smooth (HASMCs) as well as endothelial cells (HAECs) and is up-regulated by AMPK activators including metformin, rosiglitazone and alpha-lipoic acid. Tumor necrosis factor-α (TNF-α), major proinflammatory factor in the development of vascular inflammation, stimulated intracellular ROS production through increases in both mitochondrial ROS and NAD(P)H oxidase activity. Adenovirus-mediate overexpression of the PGC-1α gene to HASMCs and HAECs profoundly reduced intracellular ROS production, mitochondrial ROS production and NAD(P)H oxidase activity. Consequently, it decreased NF-κB activation and expression of MCP-1and VCAM-1 that were induced by TNF-α. This study presents the possibility that the agents increasing PGC-1α expression in the vasculature may help prevent the development of atherosclerosis

18 Introduction and Application of New Mouse Models for Metabolic Syndrome Chul-Ho Lee Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Korea Disease animal models are useful tools for understanding the underlying mechanisms of human diseases and the development of new drug target and its validation as well. To date, more than 200 mouse strains have developed for the metabolic syndrome-related researches including obesity, insulin resistance, hyperlipidemia and diabetes. Most of them are genetically modified mouse strains created by gene-introducing or targeting strategy and in part spontaneous mutant stocks. However, the genetic basis of common forms of human metabolic syndrome is multigenic rather than monogenic in origin; none of established mouse models fully meet the human syndromes. Recently, 10-interval directed recombinant congenic strain (RCS) have created by combining independent diabetes or obesity-risk conferring quantitative trait loci (QTL) from two unrelated parental strains: New Zealand Obese (NZO) and Nonobese Nondiabetic (NON). These RCSs are shown the different susceptibilities of obesity and diabetes depending on genetic constitution. RCS-1, -2 and -10 represent in a step-wise increase of diabetes incidence as increase in numbers of specific diabetogenic QTL. Similarly, RCS-6, -7, -8 and -9 represent diabetes-prone strains with different combinations of diabetogenic QTL. RCS-3, -4 and -5 represent obese strains that do not transit to diabetes. Because these obesity and diabetes syndromes reflect different collections of QTL, they are extremely relevant as models for the polygenic obesity or diabetes syndrome in humans. Thus, it seems that these RCSs may provide much more valid targets for testing the efficacy of anti-obese or diabetic drugs than the extreme obese and diabetic models currently available, as well as help to define the pathogenesis of metabolic syndrome, obesity and diabetes

19 스트레스와대사질환 가톨릭의대가정의학교실 / 통합의학교실김경수 여러개의대사위험인자가군집해서나타나는경우를 X 증후군이라고명명한이후대사증후군에대하여관심이고조되고있다. 대사증후군이갖는임상적의의는이런증후군을가진환자는관상동맥질환, 심근경색증, 뇌졸중의위험이 3배로증가하며결과적으로생존율이감소한다는데있다. 내당능장애나공복혈당장애를가진환자가대사증후군을갖는경우심혈관계사망률증가로인해생존율이감소한다는사실에서대사증후군을갖는공복혈당장애환자를고위험군으로생각하고약물치료를시작해야할필요성이제기된다. 대사증후군의병인은아직명확히알 려져있지는않지만인슐린저항성 (insulin resistance) 과만성염증상태 (proinflammatory & prothrombotic state) 가중심적인역할을할것이라는제안이대두되고있다. 현대사회는생활습관에있어서심대한변화를가져왔다. 즉체중은증가일로에있으며, 식사습관은점점건강하지못한방향으로가고있고사람들은점점좌식생활경향이증가함으로서결국혈압상승과동맥경화성위험도를증가시키는대사성변화를초래하게되었다. 실제로비만, 인슐린저항그리고당뇨병은대중적건강문제에있어서역학적으로중요한비중을차지하게되었다. 또한현대사회는사회적상황과만성적인스트레스에대처하는데있어서많은과부하를부과하고있다. 스트레스의정의는사회환경적, 심리적, 생리적개념들이복합적으로연계되어있어하나의종합개념으로이해하고접근하는것이필요하다. 부연하면일상생활중여러자극중에서우리몸에괴로움을주고두려움, 불안감, 긴장감등을유발할정도가될때이원인제공자극을스트레스원이라고부르며, 이때분비되는소위스트레스호르몬들이여러말초기관에생리반응효과를초래하는데이러한일련의정신생리현상을스트레스라고한다. 스트레스는교감신경-부신 (sympathoadrenal) 계 (system) 와시상하부-뇌하수체-부신피질 (HPA) 축을활성화시킨다. 스트레스는중추

20 신경계를통하여 방어 " (defense) 와 " 공격 (defeat) 반응과같은행동학적생리학 적반응패턴을활성화시킨다. 이것은한개체나종 (species) 의생존에유리하게작용해왔지만스트레스가만성적일때는부적응상태로될수있다. allostasis 의개념즉생리적상태와환경에대한적응, 그리고 allostatic load 는어떻게스트레스에대한반응이부적응적이되고파괴되는지를이해하는데도움이된다. 방어반응으로카테콜아민분비, 미주신경 (vagal) 활성감소 (withdrawl), 코티솔분비, 그리고레닌-안지오텐신계활성화가관여된다. 이러한매개체들은단기간스트레스동안개체를도와주는역할을한다. 그러나스트레스가잦을때에는적응 ( 대처 ) 이결핍되고스트레스반응을차단하는능력이부족하게되거나스트레스에대한반응이부족하고보상기전이활성화되어알로스타부하 (allostatic load) 가압도되고적응과정이부적응적으로되어버린다. 스트레스는심혈관질환의병태생리에관여되는데, 이것은동물실험에서훌륭하게증명되어있으나, 사람에서의연구는복잡하다. 일반적으로실험실환경을일상생활환경으로외삽하여개체에서시기적변화에따른스트레스의정량화및분류하는것과다인성심혈관질환에있어서스트레스의역할을아주정확히한다는것은어려운일이다. 그럼에도불구하고역학적연구결과들은심리사회적인자들과심혈관질환과의연관성을보여주었다. 스트레스측정의생물학적모델은잘확립된스트레스원 (stressors) 의생화학적그리고생리학적영향즉교감신경-부신계 (SAM; Sympathetic-Adrenal Medullary) 와 HPA (Hypothalamic -Pituitary-Adrenocortical) 축의활성도로부터근거된다. HPA계측정은근본적으로는내분기계측정이지만, SAM계측정은심혈관계와내분기계를반영한다. 두가지모두스트레스반응을표시한다. 좋은정확도, 신뢰도, 특이성을가진스트레스측정을위한생화학적표지자의개발은스트레스연구분야에서중요한도전이다. Brunner 등은대사증후군에서신경내분비활성의역할을조사하고이러한맥락에서심리사회적인자와스트레스의역할에대하여중요성을강조하고있다. 1990년대이후정신신경내분비면역학 (psychoneuro immunology) 이자리잡으면서스트레스관련성인병의발병기전연구에많은과학적진전이있어현재는스트레스반응기전이분자유전학수준에서많이연구되어스트레스측정법과진단법, 관리, 치료까

21 지상당히구체적으로응용하는단계에까지와있다. 현대사회에서스트레스는대 사성질환의중요한원인적요인으로인식되고있어이에대한체계적인연구가필 요할것으로사료된다

22 Pancreatic islet, one of the principal target of metabolic syndrome, and possible trials for its replacement. So-Yoon Kim, Song Lee, Jae-Hyun Eum, Seok-Woo Hong, Chul-Woo Lim, In-Sun Park Department of Anatomy, College of Medicine, Inha University, Incheon, Korea. Langerhans islet is an important endocrine organ which is involved in glucose metabolism of the body. The islets, the clusters of the endocrine cells, are scattered in the pancreatic tissue and isolated by the surrounding exocrine pancreas. Each islet consists of is organized by the elaborate assembly of the different types of endocrine cells and capillaries. The beta cell of the islets is a major cell type which produces and secretes insulin, an important peptide hormone in synchronizing the blood glucose level. Insulin secretion can be regulated by neuronal intervention as well as by the controlof the intra-islet hormones including glucagon, somatostatin and pancreatic polypeptide. Dysfunction of the insulin secretion from the beta cells of the pancreatic islets may lead to disorder of glucose metabolism and diabetes. Although complete cure of diabetes caused by irreversible islet cell injury is skeptical, many researchers have explored the beta cell replacement therapy. For a decade, transplantationof the human pancreatic islet has been applied mainly to the patients of type 1 diabetes with a low chance of success, and still suffered from insufficiency of the cadaveric donor. Therefore, stem cell research has been on the rise for the purpose of beta cell replacement. Although embryonic stem cell was once considered as a promising source of insulin secreting beta cells, more attention is concentrated on the adult pancreatic

23 stem cells showing a narrow spectrum of differentiation into only 2 pancreatic cell types, ductal cells and islet cells including insulin secreting beta cells. The stem cells arebelieved to be located in the pancreatic duct epithelial linings. Several differentiation or morphogenic factors have known to be involved in the developmental process of endocrine pancreas. However, mechanism of action and functional relation of these molecules are not well elucidated particularly in beta cell formation from adult pancreatic stem cells. We have suggested that adult pancreatic stem cells could be activated by the functional resumption of the morphogenic factors that were involved in embryonic development of pancreas in the duct system under the specific conditions such as tissue injuries. Besides the well established genes including pdx-1 and neg-3, we propose the nestin and clusterin as the new morphogenic factors for beta cell neogenesis and their functional associations. In particular, by modulation of pdx-1 and ngn-3, clusterin induces remarkable differentiation of the functional beta cellsthat secrete insulin in response to glucose stimulation

24 Natural Product as Research Tools on Metabolic Syndrome: under the Aspect for the Development Won Keun Oh Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Korea Some 50,000 species of the world's estimated total of 300,000 to 500,000 plant species are used in traditional medicine, and it suggested that less than 2 percent over 25,000 flowering plants in the World have been exhaustively studied for their potential pharmacological activities and bioactive chemicals constituents. Because chemical novelty of compounds from natural product is higher than any other source, and its chemicals are generally small molecules with drug-like properties, the research on natural products was interested as Nature's treasures yet to be explored. Furthermore, on that the metabolic syndrome is a disease related with food intake and energy expenditure, it will give new chances to us in that people are buying fewer pharmaceutical drugs and more health foods, preventive herbs and vitamins. As our screening system on metabolic syndrome, we has been interested in protein tyrosine phosphatase 1B (PTP1B) because not only as a negative regulator with the insulin signaling pathway, but also the leptin signaling pathway can be attenuated by PTPs. Since plants are a promising source for the development of new PTP1B inhibitors, we have undertaken a screen of hundreds of plant extracts against PTP1B. During this screening effort, we found that various plants inhibited in vitro PTP1B activity ( > 80% inhibition at 30 μg/ml). Finally, the inhibitory compounds could be isolated as a pure compound from the selected candidate of plant source with combinations of various column chromatography and HPLC. In this seminar, we discuss the structures of these compounds, the evaluation of their PTP1B inhibitory activity, and its applications for research of metabolic syndrome

25 Ubiquitous health care system 을이용한 대사증후군의미래형관리 가톨릭의대내분비대사내과, Ubiquitous health care 사업단윤건호 아시아지역대사증후군및당뇨병환자의특성은최근매우급격한증가를보이는점, 서구인에비하여상대적으로비만하지않은상태에서대사질환이호발하는점과비교적젊은연령에서질환이시작되는점들이다. 이러한변화를보이는환경적인이유로는급격한도시화, 산업화인데이로인하여복합당질섭취의저하와지방및단순당섭취의증가로대표되는식생활의변화, 직업의변화와운동부족이심각한원인으로제시되고있다. 물론유전적소인도중요하여서구인에비하여근육량의상대적부족, 자명한복부비만및베타세포의기능적, 양적부족이제시되고있다. 이러한특성으로인하여한국을비롯한아시아지역에서대사증후군의현황은이미서구선진국수준이며이로인한당뇨병및심혈관질환의유병률역시심각한상태이다. 더욱문제가되는점은현재개발되어사용되고있는대부분의약제들로서는질환의일시적인관리는가능하나질병의근본적인병인을개선하기에는한계가있다는것이다. 이러한한계를극복하기위해서는이지역의대사증후군의특성과병인을깊이이해하고, 보다근본적인치료에접근할수있는기초연구, 환자들의임상특성에대한분석, 신개념의생활습관관리모델개발등다방면의노력이긴요하다. 본교실에서는 2000년부터당뇨병환자들을대상으로인터넷을통한혈당관리를시도하여환자들의적극적인참여를확인한바있다. 이에힘입어 3개월간의단기효과를증명하여보고하였으며최근에는 30개월간장기간지속되는혈당조절효과를관찰하여보고하기도하였다. 이를바탕으로건강-비용분석을통하여이러한관리방법이대단히비용-효율적이라는것을밝힌바있으며, 최근에는모바일접속을이용한연결을통한방법등다양한신기술을적용하고있다. 이를기관차원에서적극적으로지원하기위하여가톨릭중앙의료원소속의가톨릭 Ubiquitous health care 사업단이설립되었으며, 사업단에서는여러부처사업등을통하여신개념의생활습관프로그램, 질환관리프로그램들을개발하고있다. 이번강연에서는매우새로운시도로서여러기술의융합을통한미래형의료로생각되고있는 Ubiquitous health care system을이용한대사증후군의미래

26 형관리에대하여소개하도록하겠다