PTEN、FoxO3a与PI3K-Akt通路在胰岛素抵抗发生机制中所起作用的实验研究
详细信息    本馆镜像全文|  推荐本文 |  |   获取CNKI官网全文
摘要
目的磷脂酰肌醇3-激酶(phosphatidylinositol 3-kinase,P13K)-Akt通路为胰岛素的主要信号传导通路,发生胰岛素抵抗时P13K-Akt通路活性降低。PTEN(phosphatase andtensin homologue deleted on chromosome 10)是一种脂质磷酸酶,最初是作为一种肿瘤抑制因子而被发现,是一个很有效的PI3K-Akt通路的负性调节因子。FoxO蛋白是一种转录因子,是P13K-Akt通路激活后的一个下游因子,FoxO可直接影响PI3K-Akt通路的最后效应即糖代谢。但目前国内外尚无胰岛素抵抗时胰岛素敏感组织PTEN及FoxO3a蛋白表达的报道。因此本研究主要观察胰岛素抵抗KKAy糖尿病小鼠胰岛素敏感组织肝、骨骼肌及脂肪组织胰岛素刺激后Aktser473磷酸化水平、PTEN、FoxO3a蛋白的表达以及罗格列酮及二甲双胍治疗后上述蛋白表达的变化,从而探计PTEN、FoxO3a与PI3K-Akt通路活性在胰岛素抵抗机制中的作用。
     方法实验动物分为C57BL/6J小鼠普通饲料喂养组、C57BL/6J小鼠高脂饲料喂养组、KKAy糖尿病小鼠未治疗组、KKAy糖尿病小鼠罗格列酮治疗组以及KKAy糖尿病小鼠二甲双胍治疗组。C57BL/6J小鼠普通饲料组普通饲料喂养至16-18周龄,处死取材;C57BL/6J高脂饲料喂养组普通饲料喂养至12周,随后高脂喂养4周后处死取材;KKAy小鼠普通饲料喂养至12周龄,随后高脂饲料喂养4周,尾静脉血测末梢血糖,连续两周随机血糖大于300mg/dl(16.7mmol/L)诊断为糖尿病;KKAy糖尿病小鼠组未治疗组在诊断为糖尿病后即处死取材;KKAy糖尿病小鼠治疗组分别给予罗格列酮(12.5mg/kg/day)以及二甲双胍(3.0g/kg/day,分两次灌胃)治疗4周后处死取材。实验动物均在处死前空腹12h,每组动物分别随机分为未用胰岛素处理组及胰岛素处理组,未用胰岛素处理组小鼠尾静脉血测空腹血糖(fasting blood glucose,FBG),眼内疵静脉取血,留取血清ELISA法测定血胰岛素后处死;胰岛素处理组胰岛素处理前后尾静脉取血测血糖,腹腔注射胰岛素(5mU/g)后10分钟处死小鼠。各组小鼠在处死后即取肝组织、股四头肌及附睾脂肪垫,组织样本加组织裂解液,高速离心取上清-70℃保存,取等量组织蛋白样本进行western blots检测组织PTEN、FoxO3a及磷酸化Akt水平,图像数据用SPSS12.0软件,多组比较采用方差分析,组间比较采用q检验。
     结果
     FBG及空腹胰岛素
     C57BL/6J小鼠高脂饲料喂养组FBG(7.13±1.30mmol/L)及空腹胰岛素(0.60±0.33ng/ml)与普通饲料喂养组FBG(6.06±0.34mmoll/L)及空腹胰岛素(0.64±0.34ng/ml)相比无显著差异(P均>0.05);KKAy糖尿病小鼠FBG(10.30±2.58mmol/)及空腹胰岛素(6.00±1.79ng/ml),较C57BL/6J小鼠普通及高脂饲料喂养组均明显升高(P均<0.001);罗格列酮治疗组FBG(6.76±1.39mmol/L)(P<0.01)及二甲双胍治疗组FBG(5.80±1.50mmol/L)(P<0.001)与KKAy糖尿病小鼠组相比均明显下降,空腹胰岛素水平罗格列酮治疗组(2.74±1.74ng/ml)(P<0.05)以及二甲双胍治疗组(2.40±1.1ng/ml)(P<0.01)与KKAy糖尿病小鼠组相比也均明显下降;罗格列酮治疗组以及二甲双胍治疗组FBG明显下降至C57BL/6J普通饲料及高脂饲料喂养组水平(P均>0.05)。罗格列酮治疗组以及二甲双胍治疗组空腹胰岛素亦明显下降,与C57BL/6J高脂饲料喂养组无差异(P均>0.05),但未降至C57BL/6J普通饲料喂养组水平(P均<0.05)。
     胰岛素刺激后Aktser473磷酸化水平
     C57BL/6J小鼠高脂饲料喂养组胰岛素刺激后Aktser473磷酸化升高水平肝(4.57±0.38倍)、骨骼肌(4.74±0.60倍)及脂肪组织(4.56±0.68倍)与C57BL/6J小鼠普通饲料喂养组胰岛素刺激后肝(4.67±0.55倍)、骨骼肌(4.82±0..22倍)及脂肪组织(4.92±0.41)Aktser473磷酸化升高水平无显著差异(P均>0.05),KKAy糖尿病小鼠胰岛素刺激后Aktser473磷酸化升高水平肝(2.46±0.65倍)、骨骼肌(2.29±0.56倍)及脂肪组织(2.50±0.14倍)较C57BL/6J普通饲料及高脂喂养组喂养组相比均显著降低(P均<0.001)。KKAy糖尿病小鼠罗格列酮胰岛素刺激后Aktser473磷酸化升高水平肝(2..77±0.26倍)、骨骼肌(2.65±0.40倍)及脂肪组织(2.54±0.60倍)以及二甲双胍治疗后胰岛素刺激后Aktser473磷酸化升高水平肝(2.56±0.18倍)、骨骼肌(2.40±0.31倍)及脂肪组织(1.99±0.44倍)与KKAy糖尿病小鼠相比无显著变化(P均>0.05)。
     PTEN蛋白
     C57BL/6J小鼠高脂喂养组骨骼肌组织PTEN的蛋白水平(0.59±0.26)较C57BL/6J小鼠普通饲料喂养组(0.18±0.19)显著升高(P<0.05),C57BL/6J小鼠高脂喂养组PTEN蛋白水平肝(6.27±1.10)及脂肪组织(2.85±0.59)与C57BL/6J小鼠普通饲料喂养组肝(5.97±1.23)及脂肪组织(2.55±0.42)相比无显著差异(P均>0.05);KKAy糖尿病小鼠肝(13.37±0.28)、骨骼肌(1.08±0.14)及脂肪组织(4.92±1.74)PTEN蛋白的表达较C57BL/6J小鼠均显著升高(P均<0.001);PTEN蛋白水平罗格列酮治疗后肝(15.60±1.06)、骨骼肌(1.13±0.21)及脂肪组织(5.50±0.95)以及二甲双胍治疗后肝(14.97±0.87)、骨骼肌(1.07±0.18)及脂肪组织(5.39±0.72)与KKAy糖尿病小鼠相比无变化(P均>0.05)。
     FoxO3a蛋白
     KKAy糖尿病小鼠脂肪组织FoxO3a蛋白水平(1.76±0.14)明显高于C57BL/6J小鼠普通饲料喂养(1.15±0.10)及高脂饲料喂养组(1.09±0.13)(P均<0.05),KKAy糖尿病小鼠罗格列酮治疗后(1.43±0.22)和二甲双胍治疗后(1.59±0.18)脂肪组织FoxO3a的蛋白水平KKAy糖尿病小鼠对照相比没有统计学差别(P均>0.05)。
     结论KKAy小鼠短期高脂喂养可以较好的模拟人类2型糖尿病发病过程;发生胰岛素抵抗时,胰岛素敏感组织肝、骨骼肌及脂肪组织PTEN的表达增加;脂肪组织FoxO3a的表达增多;高脂摄入可以使骨骼肌组织PTEN的表达增多,但对肝及脂肪组织PTEN的表达无影响;PTEN可能是一种重要的负性调节因子,调节P13K/Akt所介导的信号传导通路,在胰岛素抵抗的发生、发展中起着重要的作用。罗格列酮及二甲双胍的降糖及改善胰岛素抵抗作用与PTEN及FoxO3a可能无关,其降糖作用可能为非P13K-AKT通路。
Objective:Signaling through the phosphatidylinositol 3-kinase(PI3K)-Akt pathway is crucial for metabolic responses to insulin,and defects in PI3K-Akt signaling have been demonstrated in insulin resistance.PTEN(phosphatase and tensin homologue deleted on chromosome 10),firstly named after tumor suppressor,is a potent negative regulator of the PI3K-Akt pathway.FoxO family are transcription factors and belong to downstream molecules and then can be activated by PI3K-Akt pathway.Until now there was no report of the expression of PTEN and FoxO in insulin target tissue when insulin resistance occur.The purpose of this study is to detect protein level of PTEN,FoxO3a and insulin-stimulated phosphoserine 473-Akt in live,muscle and fat tissue in KKAy diabetic mice and the changes of these proteins after treatment of rosiglitazone and metformin,to investigate the roles of PTEN,FoxO3a and PI3K-Akt pathway in the mechanism of insulin resistance.
     Methods:Study group was divided into normal diet C57BL/6J mice group,high fat diet C57BL/6J mice group,KKAy diabetic mcie group,KKAy diabetic mice randomly assigned to rosiglitazone treating group and metformin-treating group;normal diet C57BL/6J mice group were killed utill 16-18 weeks old,high fat diet C57BL/6J mice group and KKAy mcie group were fed with normal diet until week 12,thereafter fed with high fat diet for 4 weeks and then high fat diet C57BL/6J mice group were killed.Blood glucose of KKAy mice were measured from tail vein every week since 15 week old,it would be diagnosed of diabetes if blood glucose more than 300mg/dl(16.7mmol/L) in two consecutive weeks. KKAy diabetic mice will be divided into untreating group and two treating groups. Untreating KKAy diabetic mice were killed afte diabetes were diagnoised.Two treating KKAy diabetic mice were be gaven rosiglitazone 12.5 mg/kg/day and metformin (3.0g/kg/day,divided for two times) for 4 week and then be killed.Food was withdrawn 12h before samples were taken.Each group mice were be divided into insulin-untreating mice and insulin-treating mice.Insulin-treating mice were intraperitoneally injected with insulin(5mU/g body wt) in saline,after 10 min,the mice were killed.Blood glucose were measured from tail before and after insulin treating in insulin-treating KKAy diabetic mice. After the mice were killed,dispatched the mice and took quadriceps of femoris muscle and liver tissue,added tissue lytic solution,measured the protein concentration by Bradford method and detect the PTEN,FoxO3a and phosphoserine 473-AKT protein expression in muscle and liver tissue by Western bolts methods.
     Results:
     Fasting blood glucose(FBG) and fasting insulin:Both FBG (10.30±2.58mmol/L)and fasting insulin(6.00±1.79ng/ml) of KKAy diabetic mice were significantly increased compared with normal diet C57BL/6J mice group FBG(6.06±0.34mmol/L) and fasting insulin(0.64±0.34ng/ml);FBG (7.13±1.30mmol/L) and fasting insulin(0.60±0.33ng/ml) of high fat diet C57BL/6J mice group don't increased compared with normal diet C57BL/6J mice(P<0.001).High fat diet don't impact the FBG and fasting serum insulin of C57BL/6J mice.After treating with rosiglitazone,the FBG(6.76±1.39mmol/L) and fasting serum insulin(2.74±1.74ng/ml) of KKAy diabetic mice were decreased(p<0.01 and p<0.05),so were FBG(5.80±1.50mmol/L) and fasting insulin(2.40±1.1ng/ml) in KKAy diabetic mice treating with metformin ((p<0.001 and p<0.01).
     Insulin stimulation of phosphoserine 473-Akt:Insulin-induced phosphoserine 473-Akt were significantly decreased in liver(2.46±0.65-fold),muscle(2.29±0.56-fold)and fat (2.50±0.14-fold) tissue of KKAy diabetic mice compared with liver(4.67±0.55-fold),muscle(4.82±0.22-fold)and fat(4.92±0.41-fold)tissue of normal diet C57BL mice(P<0.001).Insulin-induced phosphoserine 473-AKT were not significantly decreased in liver(4.57±0.38-fold),muscle(4.74±0.60-fold)and fat(4.56±0.68-fold)tissue of high fat diet C57BL/6J mice group compared with normal diet C57BL/6J mice (P<0.001).High fat don't impact the insulin-induced phosphoserine 473-Akt in C57BL/6J mice.Insulin-induced phosphoserine 473-AKT in live(2.77±0.26-fold),musle(2.65± 0.40-fold) and fat(2.54±0.60-fold) tissue of rosiglitazone-treated and live(2.56±0.18-fold),musle(2.40±0.31-fold) and fat(1.99±0.44-fold) tissue of metformin-treated KKAy diabetic mice are all not changed compared with those in KKAy diabetic mice(P>0.05).
     PTEN protein level:PTEN protein level was significantly elevated in live(13.37±0.28),muscle(1.08±0.14) and fat(4.92±1.74)tissue of KKAy diabetic mice and in muscle tissue(0.59±0.26) of C57BL high fat diet group compared to live(5.97±1.23),muscle((0.18±0.19)and fat(2.55±0.42) of C57BL normal diet groups.(P<0.001 and P<0.05).PTEN protein level was not significantly elevated in live(6.27±1.10) and fat(2.85±0.59) tissue of high fat diet C57BL mice compared with C57BL normal diet groups(P>0.05).PTEN protein level in live(15.60±1.06),musle(1.13±0.21) and fat(5.50±0.95) tissue of rosiglitazone-treated and live(14.97±0.87),musle(1.07±0.18)and fat(5.39±0.72) tissue of metformin-treated KKAy diabetic mice are all not changed compared with those in KKAy diabetic mice(P>0.05).
     FoxO3a protein level:FoxO3a protein level(1.76±0.14) was significantly elevated in fat tissue of KKAy diabetic mice compared to that in fat tissue(1.15±0.10) of normal diet C57BL group(p<0.05).FoxO3a protein level(1.09±0.13) of fat tissue of high fat diet C57BL mice was not significantly elevated compared with C57BL normal diet groups(P>0.05) FoxO3a protein level in fat tissue of rosiglitazone-treated(1.43±0.22) and metformin-treated KKAy diabetic mice(1.59±0.18) are all not changed compared with those in KKAy diabetic mice.
     Conclusion:KKAy mice given high fat diet for a short period is a good animal model of type 2 diabetes.The expression of PTEN were increased at insulin-sensitive tissue live,skeletal muscle and fat and FoxO3a was increased at fat tissue of insulin resistance. High fat diet can increase the expression of PTEN at skeletal muscle.PTEN may be a potent negative modulator of the PI3K-Akt pathway and then play an important role in the development of insulin resistance.Rosiglitazone and metformin can reduce blood glucose and improve insulin resistance.But the mechanism may not correlate with the expression of PTEN and FoxO3a in insulin sensitive tissue and then also may not related to the PI3K-Akt pathway.
引文
1. Sun XJ,Wang LM, Zhang Y et al. Role of IRS-2 in insulin and cytokine signalling. Nature. 1995 Sep 14;377(6545):173-7.
    
    2. Waters SB,Pessin JE Insulin receptor substrate 1 and 2 (IRS1 and IRS2): what a tangled web we weave.Trends Cell Biol. 1996 Jan;6(1): 1-4.
    
    3. Lavan BE,Fantin VR,Chang ET et al. A novel 160-kDa phosphotyrosine protein in insulin-treated embryonic kidney cells is a new member of the insulin receptor substrate family.J Biol Chem. 1997 Aug 22;272(34):21403-7.
    
    4. Lavan BE,Lane WS, and Lienhard GE.The 60-kDa phosphotyrosine protein in insulin-treated adipocytes is a new member of the insulin receptor substrate family.J Biol Chem. 1997 Apr 25;272(17):11439-43.
    
    5. Waters SB,Pessin JE Insulin receptor substrate 1 and 2 (IRS1 and IRS2): what a tangled web we weave.Trends Cell Biol. 1996 Jan;6(1): 1-4.
    
    6. Lavan BE,Fantin VR,Chang ET et al. A novel 160-kDa phosphotyrosine protein in insulin-treated embryonic kidney cells is a new member of the insulin receptor substrate family. J Biol Chem. 1997 Aug 22;272(34):21403-7.
    
    7. Lavan BE,Lane WS, and Lienhard GE.The 60-kDa phosphotyrosine protein in insulin-treated adipocytes is a new member of the insulin receptor substrate family. J Biol Chem. 1997 Apr 25;272(17):11439-43.
    
    8. Kotani K,Carozzi AJ,Sakaue H et al.Requirement for phosphoinositide 3-kinase in insulin-stimulated GLUT4 translocation in 3T3-L1 adipocytes.Biochem Biophys Res Commun. 1995 Apr 6;209(1):343-8.
    
    9. Jhun BH,Rose DW,Seely BL et al. Microinjection of the SH2 domain of the 85-kilodalton subunit of phosphatidylinositol 3-kinase inhibits insulin-induced DNA synthesis and c-fos expression. Mol Cell Biol. 1994 Nov; 14(11):7466-75
    
    l0.Kohn AD,Summers SA Birnbaum MJ. Expression of a constitutively active Akt Ser/Thr kinase in 3T3-L1 adipocytes stimulates glucose uptake and glucose transporter 4 translocation.J Biol Chem. 1996 Dec 6;271(49):31372-8.
    
    11.Cho,H.,J.Mu,J.K.Kim et al.Insulin resistance and a diabetes mellitus-like syndrome in mice lacking the protein kinase Akt2(PKB beta).science 2001,292:1728-1731
    12. Jiang ZY,QL Zhou,KA Coleman et al. Insulin signaling through AKT/Prote Insulin receptor substrate (IRS)-2 is dephosphorylated more rapidly than IRS-1 via its association with phosphatidylinositol 3-kinase in skeletal muscle cells.J Biol Chem. 1997 May 9;272(19):12868-73.
    13.Katome T, obata T, Matsushima R et al. Use of RNA interference-mediated gene silencing and adenoviral overexpression to elucidate the roles of AKT/protein kinase B isoforms in insulin actions. J Biol Chem. 2003 Jul 25;278(30):28312-23.
    
    14. Garofalo RS,Orena SJ and Rafidi K et al. Severe diabetes, age-dependent loss of adipose tissue, and mild growth deficiency in mice lacking Akt2/PKB beta.J Clin Invest. 2003 Jul;112(2): 197-208. Epub 2003 Jul 3.
    
    15.Wang Q, Somwar R, Bilan PJ et al. Protein kinase B/Akt participates in GLUT4 translocation by insulin in L6 myoblasts. Mol Cell Biol. 1999 Jun;19(6):4008-18.
    
    16.Alessi DR,Downes CP. The role of PI3-kinse in insulin action. Biochim Biophys Acta.1998; 1436:151-164
    
    17. Taha C,Klip A. The insulin signaling pathway. J Membr Bio. 1999; 169:1 -12
    
    18. Saltiel AR: New perspectives into the molecular pathogenesis and treatment of type 2 diabetes. Cell.2001,104:517-529
    
    19. Virkamaki A,Ueki K,Kaha CR:Protein-protein interaction in insulin signaling and the molecular mechanisms of insulin resistance.J Clin Invest. 1999,103:931-941
    
    20. Stambolic VCK,Suzuki Akira and Jose Lois de la Pompa and et al. Negative regulation of PKB/Akt-dependent cell survial by the tumoe suppressor PTEN.cell.1998,95:29-39
    
    21. Alessi DR,Cohen P Mechanism of activation and function of protein kinase B.Curr Opin Genet Dev. 1998 Feb;8(1):55-62.
    
    22. Alessi DR,James SR,Downes CP et al. Characterization of a 3-phosphoinositide-dependent protein kinase which phosphorylates and activates protein kinase Balpha.Curr Biol. 1997 Apr 1;7(4):261-9.
    
    23. Steck PA,Pershouse MA, Jasser SA et al. Identification of a candidate tumour suppressor gene, MMAC1, at chromosome 10q23.3 that is mutated in multiple advanced cancers.Nat Genet. 1997 Apr; 15(4):356-62.
    
    24. LiJ,Yen C,Liaw D et al. PTEN, a putative protein tyrosine phosphatase gene mutated in human brain, breast, and prostate cancer Science. 1997 Mar 28;275(5308):1943-7
    
    25. Vazquez F, and Sellers WR. The PTEN tumor suppressor protein: an antagonist of phosphoinositide 3-kinase signaling. Biochim Biophys Acta. 2000 Feb 14;1470(1):M21-35
    
    26. Lee JO,Yang H, Georgescu MM. Cell. Crystal structure of the PTEN tumor suppressor: implications for its phosphoinositide phosphatase activity and membrane association. 1999 Oct 29;99(3):323-34.
    
    27. Iida S, Ono A, Sayama K, Hamaguchi T, Accelerated decline of blood glucose after intravenous glucose injection in a patient with Cowden disease having a heterozygous germline mutation of the PTEN/MMAC1 gene.Anticancer Res.2000 May-Jun;20(3B):1901-4.
    
    28.tambolic V, A Suzuki, J L de la Pompa et al. Negative regulation of PKB/Akt-depent cell survival by the tumor suppressor PTEN. Cell 1998, 95:29-39.
    
    29.Nakashima N, Sharma PM, Imamura T et al. The tumor suppressor PTEN negatively regulates insulin signaling in 3T3-L1 adipocytes. J Biol Chem 2000,275:12889-12895
    
    30.Hiraku O, Hideki Katagiri, Makoto Funaki et al. Regulation of phosohoinesitide metabolism,Akt phosphorylation, and glucose transport by PTEN in 3T3-L1 adipocytes. Mol Endocrinol ,2001,August, 15(8):1411-1422
    
    31. Gil EB, Malone link E, Liu LX et al. Regulation of the insulin-like developmental pathway of Caenorhabditis elegans by a homolog of the PTEN tumor suppressor gene.Proc Natl Acad Sci U S A. 1999 Mar 16;96(6):2925-30
    32.Mihaylova VT,Borland CZ,Manjarrez L et al. The PTEN tumor suppressor homolog in Caenorhabditis elegans regulates longevity and dauer formation in an insulin receptor-like signaling pathway Proc Natl Acad Sci U S A. 1999 Jun 22;96(13):7427-32.
    
    33.Ogg S and Ruvkun G. The C. elegans PTEN homolog, DAF-18, acts in the insulin receptor-like metabolic signaling pathway. Mol Cell. 1998 Dec;2(6):887-93
    
    34. Sasaoka T,Wada T,Tsuneki H. Lipid phosphatases as a possible therapeutic target in cases of type 2 diabetes and obesity. Pharmacol Ther.2006,112(3):799-809.
    
    35. Dan F. Lazar ,Alan R .Lipid phosphatases as drug discovery targets for type 2 diabetes.Nat Rev Drug Discov. 2006 ,5(4):333-42.
    
    36. Madeline Butler,Robert A. Mckay, Ian J. Popoff et al. Specific inhibition of PTEN expression reverses hyperglycemia in diabetic mice. Diabetes.2002,51:1028-1034.
    
    37.Bangyan Stiles, Ying Wang, Andreas Stahl, et al. Liver-specific deletion of negative regulator Pten results in fatty liver and insulin hypersensitivity. Proc Natl Acad Sci U S A. 2004 17; 101 (7):2082-2087.
    
    38. Christine Kurlawalla-Martinez, Bangyan Stiles, Ying Wang, et al. Insulin hypersensitivity and resistance to streptozotocin-induced diabetes in mice lacking PTEN in adipose tissue. Mol Cell Biol. 2005 Mar;25(6):2498-2510.
    
    39.Nadeeja Wijesekara ,Daniel Konarad, Mohamed Eweida, et al. Muscle-specific Pten deletion protects against insulin resistance and diabetes. Mol Cell Biol.2005;25(3):1135-1145.
    
    40. Erika Rosivatz, Jonathan GMatthews, Neil Q.Mcdonald, et al. A small-molecule inhibitor for phosphatase and tensin homologue deleted on chromosome 10(PTEN). Acs Chem Biol. 2007,1(12):780-790.
    
    41.Y.T. Lo,C.J.Tsao,I.M.Liu, et al. Increase of PTEN gene expression in insulin resistance.Horm Metab Res.2004;36:662-666.
    
    42.Kim SJ., Winter K., Nian C, et al. Glucose-dependent insulinotropic polypeptide(GIP) stimulation of pancreatic β-cell survival is dependent upon phosphatidylinositol 3 kinase (PI3K)/Protein kinase B (PKB) signaling,inacrive of the forkhead transcripation factor Foxol, and down-regulation of bax expression. J Bio Chem. 2005, 280(10): 22297-22307.
    
    43.Yasutomi K., Shinji M., Miki S. and et al. Skeletal Muscle FOXO1 (FKHR) Transgenic Mice have less skeletal muscle mass, down-regulated type 1 (slow twich/ red muscle) fiber genes, and impaired glycemic control. J Biol. Chem.2004, 279(39): 41114-41123.
    
    44. Nakae J., Kitamura T., Silver D. L., and Accili D. The forkhead transcription factor Foxol(Fkhr) confers insulin sensitivity onto glucose-6-phosphatase expression. J Clin Invest, 2001, 108(9): 1359-1367.
    
    45. Nakae J., Biggs W.H., Kiatamura T., and et al. Regulation of insulin action and pancreatic beta-cell function by mutated alleles of the gene encoding forkhead transcription factor Foxol. Nat Genet. 2002, 32: 245-253.
    
    46.Tang Y,Osawa Haruhiko, Onuma Hiroshi et al. Improvement in insulin resistance and the restoration of reduced phosphodiesterase 3B gene expression by pioglitazone in adipose tissue of obese diabetic KKAy mice.Diabetes. 1999,48:1830-35
    
    47. Chang AY,Wyse BM,Copeland EJ et al.The Upjohn colony of KKAy mice : a model for obese type 2 diabetes. In Diabetes 1985. Serrano-Rios M,Lefebvre PJ,Eds.Elsevier. Amsterdam, 1986,p.466-470
    
    48. Bonini JA,Colca JR, Dailey C et al. Compensatory alterations for insulin signal transduction and glucose transport in insulin-resistant diabetes Am J Physiol.1995 Oct;269(4 Pt l):E759-65
    
    49. Muherjee R, Divies PJ, Crombie DL, et al. Sensitation of diabetic and obese mice to insulin by retinoid X receptor agnonists. Nature. 1997, 386 (6623);407-410.
    
    50.Valensi P, Behar A, Cohen-Boulakia F, et al. In vivo kinetic of 123iodine-labelled insulin in skeletal muscle of patients with type 2 diabetes: Effect of metformin. Diabetes Metab. 2002, 28(2): 95-103.
    51.Patel L, Pass I,Coxon P et al. Tumor suppressor and anti-inflammatory actions of PPARgamma agonists are mediated via upregulation of PTEN.Curr Biol.2001 May 15;11(10):764-8
    52.Carvalho, E, Rondinone C, and Smith U. Insulin resistance in fat cells from obese Zucker rats—evidence for an impaired activation and translocation of protein kinase B and glucose transporter 4. Mol Cell Biochem 206: 7-16, 2000
    53.Krook, A, Kawano Y, Song XM, Efendic S, Roth RA, Wallberg-Henriksson H,and Zierath JR. Improved glucose tolerance restores insulin-stimulated Akt kinase activity and glucose transport in skeletal muscle from diabetic Goto-Kakizaki rats. Diabetes 46: 2110-2114, 1997
    54. Kim, Y, Peroni O, Franke T, and Kahn B. Divergent regulation of Akt1 and Akt2 isoforms in insulin target tissues of obese Zucker rats. Diabetes 49:847-856, 2000
    55.Vaag A,Henriksen JE and Beck-Nielsen H. Decreased insulin activation of glycogen synthase in skeletal muscles in young nonobese Caucasian first-degree relatives of patients with non-insulin-dependent diabetes mellitus.J Clin Invest. 1992 Mar;89(3):782-8
    
    56. Totsuka Y,Nagao Y Horii T et al. Physical performance and soleus muscle fiber composition in wild-derived and laboratory inbred mouse strains.J Appl Physiol. 2003 Aug;95(2):720-7.
    
    57. Zierath JR,Houseknecht L Gnudi L et al. High-fat feeding impairs insulin-stimulated GLUT4 recruitment via an early insulin-signaling defect.Diabetes. 1997 Feb;46(2):215-23.
    
    58.Lillioja S,Young AA, Culter CL et al. Skeletal muscle capillary density and fiber type are possible determinants of in vivo insulin resistance in man.J Clin Invest. 1987 Aug;80(2):415-24.
    
    59. Song XM,Ryder JW Kawano Y et al. Muscle fiber type specificity in insulin signal transduction.Am J Physiol. 1999 Dec;277(6 Pt 2):R1690-6.
    
    60.Nadler ST,. Stoehr JP, Rabaglia ME.Normal Akt/PKB with reduced PI3K activation in insulin-resistant mice.Am J Physiol Endocrinol Metab. 2001 Dec;281(6):E1249-54.
    61.Abel ED,Peroni O, Kim YB, et al. Adipose-selective targeting of the GLUT4 gene impairs insulin action in muscle and liver.Nature. 2001 Feb 8;409(6821):729-33.
    62.Kahn BB,Flier JS. Obesity and insulin resistance.J Clin Invest. 2000 Aug;106(4):473-81.
    63.Minokoshi Y, Kahn CR, Kahn BB. Tissue-specific ablation of the GLUT4 glucose transporter or the insulin receptor challenges assumptions about insulin action and glucose homeostasis.J Biol Chem. 2003 Sep 5;278(36):33609-12.Epub 2003 Jun 4.
    64. Shepherd PR, Kahn BB. Glucose transporters and insulin action—implications for insulin resistance and diabetes mellitus.N Engl J Med. 1999 Jul 22;341(4):248-57.
    65.Nakashima N,Sharma PM,Imamura T et al. The tumor suppressor PTEN negatively regulates insulin signaling in 3T3-L1 adipocytes.J Biol Chem. 2000 Apr 28;275(17):12889-95.
    
    66. Ono H,Katagiri H,Funaki M et al. Regulation of phosphoinositide metabolism,Akt phosphorylation, and glucose transport by PTEN (phosphatase and tensin homolog deleted on chromosome 10) in 3T3-L1 adipocytes.Mol Endocrinol.2001 Aug;15(8):1411-22.
    
    67.Tang X,Powelka AM,Soriano NA et al. PTEN, but not SHIP2, suppresses insulin signaling through the phosphatidylinositol 3-kinase/Akt pathway in 3T3-L1 adipocytes.J Biol Chem. 2005 Jun 10;280(23):22523-9. Epub 2005 April.
    
    68.Kanoh Y, Bandyopadhyay G,Sajan MP, Rosiglitazone, insulin treatment,and fasting correct defective activation of protein kinase C -zeta/lambda by insulin in vastus lateralis muscles and adipocytes of dabetics rats.Endocrinology. 2001 Apr; 142(4): 1595-605
    69. Kanoh Y, Bandyopadhyay G, Sajan Mini P et al. Thiazolidinedione treatment enhances insulin effects on protein kinase C-zeta /lambda activation and glucose transport in adipocytes of nondiabetic and Goto-Kakizaki type II diabetic rats. J Biol Chem. 2000 Jun 2;275(22):16690-6.
    
    70. Boden G,Chen X,Ruiz J et al. Mechanisms of fatty acid-induced inhibition of glucose uptake. J Clin Invest. 1994 Jun;93(6):2438-46
    
    71. Boden GRole of fatty acids in the pathogenesis of insulin resistance and NIDDM.Diabetes 1997,46:3-10,
    
    72. Boden GFree fatty acids(FFA): a link between obesity and insulin resistance .Front Biosci 1998 3:D169-D175
    
    73. Morris BJ. A forkhead in the road to longevity: the molecular basis of lifespan becomes clear. J Hypertens. 2005,23:1285-1309.
    
    74. Anitha M, Gondha C, Sutliff R, et al. GDNF resues hyperglycemia-induced diabetic enteric neuropathy through activation of the PI3k/Akt pathway. J Clin Invest. 2006; 116:344-356.
    
    75.Relling D, Esberg LB, Fang CX, et al. High-fat diet-induced juvenile obesity leads to cardiomyocyte dysfunction and upregulation of FoxO3a transcription factor independent of lipotoxity and apoptosis. J Hypertens. 2006, 24:549-561.
    
    76. Rosivatz E,Matthews JG, Mcdonald NQ, et al. A small molecule inhibitor for phosphatase and tensin homologue deleted on chromosome 10 (PTEN). ACS Chem Biol. 2006 Dec 15;1(12):780-90
    1.Garofalo RS,Orena SJ and Rafidi K et al.Severe diabetes,age-dependent loss of adipose tissue,and mild growth deficiency in mice lacking Akt2/PKB beta.J Clin Invest.2003 Jul;112(2):197-208.Epub 2003 Jul 3.
    2.Wang Q,Somwar R,Bilan PJ et al.Protein kinase B/Akt participates in GLUT4 translocation by insulin in L6 myoblasts.Mol Cell Biol.1999Jun;19(6):4008-18.
    3.Alessi DR,Downes CP.The role of PI3-kinse in insulin action.Biochim Biophys Acta.1998;1436:151-164
    4. Taha C,Klip A. The insulin signaling pathway. J Membr Bio. 1999; 169:1 -12
    
    5. Saltiel AR: New perspectives into the molecular pathogenesis and treatment of type 2 diabetes. Cell.2001,104:517-529
    
    6. Carvalho, E, Rondinone C, and Smith U. Insulin resistance in fat cells from obese Zucker rats—evidence for an impaired activation and translocation of protein kinase B and glucose transporter 4. Mol Cell Biochem 206: 7-16, 2000
    
    7. Krook, A, Kawano Y, Song XM, Efendic S, Roth RA, Wallberg-Henriksson H,and Zierath JR. Improved glucose tolerance restores insulin-stimulated Akt kinase activity and glucose transport in skeletal muscle from diabetic Goto-Kakizaki rats. Diabetes 46: 2110-2114, 1997
    
    8. Kim, Y, Peroni O, Franke T, and Kahn B. Divergent regulation of Akt1 and Akt2 isoforms in insulin target tissues of obese Zucker rats. Diabetes 49:847-856, 2000
    
    9. Sun XJ,Wang LM, Zhang Y et al. Role of IRS-2 in insulin and cytokine signalling. Nature. 1995 Sep 14;377(6545):173-7.
    
    10.Waters SB,Pessin JE Insulin receptor substrate 1 and 2 (IRS1 and IRS2): what a tangled web we weave.Trends Cell Biol. 1996 Jan;6(1):1-4.
    11.Lavan BE,Fantin VR,Chang ET et al. A novel 160-kDa phosphotyrosine protein in insulin-treated embryonic kidney cells is a new member of the insulin receptor substrate family.J Biol Chem. 1997 Aug 22;272(34):21403-7.
    
    12.Lavan BE,Lane WS, and Lienhard GE.The 60-kDa phosphotyrosine protein in insulin-treated adipocytes is a new member of the insulin receptor substrate family.J Biol Chem. 1997 Apr 25;272(17):11439-43.
    
    13.Waters SB,Pessin JE Insulin receptor substrate 1 and 2 (IRS1 and IRS2): what a tangled web we weave.Trends Cell Biol. 1996 Jan;6(1):1-4.
    14.Lavan BE,Fantin VR,Chang ET et al. A novel 160-kDa phosphotyrosine protein in insulin-treated embryonic kidney cells is a new member of the insulin receptor substrate family. J Biol Chem. 1997 Aug 22;272(34):21403-7.
    
    15.Lavan BE,Lane WS, and Lienhard GE.The 60-kDa phosphotyrosine protein in insulin-treated adipocytes is a new member of the insulin receptor substrate family.J Biol Chem. 1997 Apr 25;272(17):11439-43.
    
    16.Kotani K,Carozzi AJ,Sakaue H et al.Requirement for phosphoinositide 3-kinase in insulin-stimulated GLUT4 translocation in 3T3-L1 adipocytes.Biochem Biophys Res Commun. 1995 Apr 6;209(1):343-8.
    
    17.Jhun BH,Rose DW,Seely BL et al. Microinjection of the SH2 domain of the 85-kilodalton subunit of phosphatidylinositol 3-kinase inhibits insulin-induced DNA synthesis and c-fos expression. Mol Cell Biol. 1994 Nov;14(11):7466-75
    
    18.Kohn AD,Summers SA Birnbaum MJ. Expression of a constitutively active Akt Ser/Thr kinase in 3T3-L1 adipocytes stimulates glucose uptake and glucose transporter 4 translocation.J Biol Chem. 1996 Dec 6;271(49):31372-8.
    
    19.Cho,H.,J.Mu,J.K.Kim et al.Insulin resistance and a diabetes mellitus-like syndrome in mice lacking the protein kinase Akt2(PKB beta).science 2001,292:1728-1731
    
    20.Jiang ZY,QL Zhou,KA Coleman et al. Insulin signaling through AKT/Protein kinase B analyzed by small interfering RNA-mediated gene silencing.Proc Natl Acad Sci USA.2003,100:7569-7574
    
    21.Katome T, obata T, Matsushima R et al. Use of RNA interference-mediated gene silencing and adenoviral overexpression to elucidate the roles of AKT/protein kinase B isoforms in insulin actions. J Biol Chem. 2003 Jul 25;278(30):28312-23.
    
    22.Quon MJ,Chen H,Ing BL, et al. Roles of 1-phosphatidylinositol 3-kinase and ras in regulating translocation of GLUT4 in transfected rat adipose cells.Mol Cell Biol. 1995 Oct; 15(10):5403-11.
    23.Katagiri H,Asano T,Ishihara H, et al. Roles of PI 3-kinase and Ras on insulin-stimulated glucose transport in 3T3-L1 adipocytes.Am J Physiol. 1997 Feb;272(2Pt1):E326-31.
    
    24.Katagiri H,Asano T, Inukai H et al. Overexpression of catalytic subunit p110alpha of phosphatidylinositol 3-kinase increases glucose transport activity with translocation of glucose transporters in 3T3-L1 adipocytes.J Biol Chem.1996 Jul 19;271(29): 16987-90.
    
    25.0gihara T,Shin RC,Anai M.Insulin receptor substrate (IRS)-2 is dephosphorylated more rapidly than IRS-1 via its association with phosphatidylinositol 3-kinase in skeletal muscle cells. J Biol Chem. 1997 May 9;272(19):12868-73.
    
    26.Asono T,Kanda A,Katagiri H.p110beta is up-regulated during differentiation of 3T3-L1 cells and contributes to the highly insulin-responsive glucose transport activity.J Biol Chem. 2000 Jun 9;275(23):17671-6.
    
    27.Aania M,Funaki M,Ogihara T.Altered expression levels and impaired steps in the pathway to phosphatidylinositol 3-kinase activation via insulin receptor substrates 1 and 2 in Zucker fatty rats.Diabetes. 1998 Jan;47(1): 13-23.
    
    28.Steck PA,Pershouse MA, Jasser SA et al. Identification of a candidate tumour suppressor gene, MMAC1, at chromosome 10q23.3 that is mutated in multiple advanced cancers.Nat Genet. 1997 Apr;15(4):356-62.
    
    29.LiJ,Yen C,Liaw D et al. PTEN, a putative protein tyrosine phosphatase gene mutated in human brain, breast, and prostate cancer Science. 1997 Mar 28;275(5308):1943-7
    
    30. Vazquez F, and Sellers WR. The PTEN tumor suppressor protein: an antagonist of phosphoinositide 3-kinase signaling. Biochim Biophys Acta. 2000 Feb 14;1470(1):M21-35
    
    31.Lee JO,Yang H, Georgescu MM. Cell. Crystal structure of the PTEN tumor suppressor: implications for its phosphoinositide phosphatase activity and membrane association. 1999 Oct 29;99(3):323-34.
    
    32. Accelerated decline of blood glucose after intravenous glucose injection in a patient with Cowden disease having a heterozygous germline mutation of the PTEN/MMAC1 gene.Anticancer Res. 2000 May-Jun;20(3B):1901-4.
    
    33.Patel L, Pass I,Coxon P et al. Tumor suppressor and anti-inflammatory actions of PPARgamma agonists are mediated via upregulation of PTEN.Curr Biol.2001 May 15;11(10):764-8
    
    34.1ida S, Ono A, Sayama K, Hamaguchi T, Accelerated decline of blood glucose after intravenous glucose injection in a patient with Cowden disease having a heterozygous germline mutation of the PTEN/MMAC1 gene.Anticancer Res.2000 May-Jun;20(3B):1901-4.
    
    35.tambolic V, A Suzuki, J L de la Pompa et al. Negative regulation of PKB/Akt-depent cell survival by the tumor suppressor PTEN. Cell 1998, 95:29-39.
    
    36.Nakashima N, Sharma PM, Imamura T et al. The tumor suppressor PTEN negatively regulates insulin signaling in 3T3-L1 adipocytes. J Biol Chem 2000,275:12889-12895
    
    37.Hiraku O, Hideki Katagiri, Makoto Funaki et al. Regulation of phosohoinesitide metabolism,Akt phosphorylation, and glucose transport by PTEN in 3T3-L1 adipocytes. Mol Endocrinol ,2001,August, 15(8): 1411-1422
    
    38.Gil EB, Malone link E, Liu LX et al. Regulation of the insulin-like developmental pathway of Caenorhabditis elegans by a homolog of the PTEN tumor suppressor gene.Proc Natl Acad Sci U S A. 1999 Mar 16;96(6):2925-30
    
    39.Mihaylova VT,Borland CZ,Manjarrez L et al. The PTEN tumor suppressor homolog in Caenorhabditis elegans regulates longevity and dauer formation in an insulin receptor-like signaling pathway Proc Natl Acad Sci U S A. 1999 Jun 22;96(13):7427-32.
    40.Ogg S and Ruvkun G. The C. elegans PTEN homolog, DAF-18, acts in the insulin receptor-like metabolic signaling pathway. Mol Cell. 1998 Dec;2(6):887-93
    
    41.Nakashima N,Sharma PM,Imamura T et al. The tumor suppressor PTEN negatively regulates insulin signaling in 3T3-L1 adipocytes.J Biol Chem. 2000 Apr 28;275(17): 12889-95.
    
    42.Ono H,Katagiri H,Funaki M et al. Regulation of phosphoinositide metabolism,Akt phosphorylation, and glucose transport by PTEN (phosphatase and tensin homolog deleted on chromosome 10) in 3T3-L1 adipocytes.Mol Endocrinol. 2001 Aug;15(8):1411-22.
    
    43.Tang X,Powelka AM,Soriano NA et al. PTEN, but not SHIP2, suppresses insulin signaling through the phosphatidylinositol 3-kinase/Akt pathway in 3T3-L1 adipocytes.J Biol Chem. 2005 Jun 10;280(23):22523-9. Epub 2005 Apr 11.
    
    44.Madeline Butler,Robert A. Mckay, Ian J. Popoff et al. Specific inhibition of PTEN expression reverses hyperglycemia in diabetic mice. Diabetes.2002,51:1028-1034.
    
    45.Rosivatz E,Matthews JG, Mcdonald NQ, et al. A small molecule inhibitor for phosphatase and tensin homologue deleted on chromosome 10 (PTEN). ACS Chem Biol. 2006 Dec 15;l(12):780-90
    
    46.Bangyan Stiles, Ying Wang, Andreas Stahl, et al. Liver-specific deletion of negative regulator Pten results in fatty liver and insulin hypersensitivity. Proc Natl Acad Sci U S A. 2004 17;101(7):2082-2087.
    
    47.Nadeeja Wijesekara ,Daniel Konarad, Mohamed Eweida, et al. Muscle-specific Pten deletion protects against insulin resistance and diabetes. Mol Cell Biol.2005;25(3):1135-1145.
    48.Christine Kurlawalla-Martinez,Bangyan Stiles,Ying Wang,et al.Insulin hypersensitivity and resistance to streptozotocin-induced diabetes in mice lacking PTEN in adipose tissue.Mol Cell Biol.2005 Mar;25(6):2498-2510.
    49.曾静波,李玉秀,王姮等.胰岛素抵抗糖尿病KKAy小鼠肌肉和肝组织PTEN 蛋白表达增强.基础医学与临床.2007,27(2):166-168.
    50.Y.T.Lo,C.J.Tsao,I.M.Liu,et al.Increase of PTEN gene expression in insulin resistance.Horm Metab Res.2004;36:662-666.
    51.Hansen L,Jensen JN,Ekstrom CT,et al.Studies of variability in the PTEN gene among Danish caucasian patients with Type Ⅱ diabetes mellitus.Diabetologia.2001 Feb;44(2):237-40.
    52.Ishihara H,Sasaoka T,Kagawa S,et al.Association of the polymorphisms in the 5'-untranslated region of PTEN gene with type 2 diabetes in a Japanese population.FEBS Lett.2003 Nov 20;554(3):450-4.

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700