stedman.mc.duke.edu  
   
School of Medicine » Sarah W. Stedman Nutrition & Metabolism Center
Faculty & Staff

Scott A. Summers, PhD

Associate Professor
Division of Endocrinology, Metabolism & Nutrition
Duke-NUS Medical School in Singapore
 
 
 
Dr. Scott Summers holds joint appointments with the Stedman Center in Durham and the new Duke-NUS Medical School in Singapore.  His integrated laboratories at these two locations study the relationship between the accumulation of ectopic fats during obesity with the development of diabetes and cardiovascular disease.  In particular, Dr. Summers’ group made the observation in 2007 that a particular derivative of fat, termed ceramide, is one of the more toxic metabolites which accumulates in the obese.  His current efforts are directed at assessing the therapeutic potential of modulating levels of ceramides in the treatment of metabolic diseases and elucidating the molecular networks controlling ceramide production and action.  Prior to joining the Stedman Center Dr. Summers held faculty appointments at Colorado State University and the University of Utah, and he conducted postdoctoral training at the University of Pennsylvania.  He has received grant support from the National Institutes of Health, American Diabetes Association, American Heart Association, March of Dimes, the National Medical Research Council of Singapore, and the Agency for Science, Technology and Research (A*STAR) of Singapore.
 
Publications
 
1.                  Wandel S, Schurmann A, Becker W, Summers SA, Shanahan MF, Joost HG. (1994). Substitution of conserved tyrosine residues in helix 4 (Y143) and 7 (Y293) affects the activity, but not IAPS-forskolin binding, of the glucose transporter GLUT4. FEBS Lett, 348(2), 114-8.
2.                  Wandel S, Schurmann A, Becker W, Summers SA, Shanahan MF, Joost HG. (1995). Mutation of two conserved arginine residues in the glucose transporter GLUT4 supresses transport activity, but not glucose-inhibitable binding of inhibitory ligands. Naunyn Schmiedebergs Arch Pharmacol, 353(1), 36-41.
3.                  Wandel S, Buchs A, Schurmann A, Summers SA, Powers AC, Shanahan MF, Joost HG. (1996). Glucose transport activity and ligand binding (cytochalasin B, IAPS-forskolin) of chimeric constructs of GLUT2 and GLUT4 expressed in COS-7-cells. Biochim Biophys Acta, 1284(1), 56-62.
4.                  Summers SA, Guebert BA, Shanahan MF. (1996). Polyphosphoinositide inclusion in artificial lipid bilayer vesicles promotes divalent cation-dependent membrane fusion. Biophys J, 71(6), 3199-206.
5.                  Kohn AD, Summers SA, Birnbaum MJ, Roth RA. (1996). Expression of a constitutively active Akt Ser/Thr kinase in 3T3-L1 adipocytes stimulates glucose uptake and glucose transporter 4 translocation. J Biol Chem, 271(49), 31372-8.
6.                  Summers SA, Birnbaum MJ. (1997). A role for the serine/threonine kinase, Akt, in insulin-stimulated glucose uptake. Biochem Soc Trans, 25(3), 981-8.
7.                  Kohn AD, Barthel A, Kovacina KS, Boge A, Wallach B, Summers SA, Birnbaum MJ, Scott PH, Lawrence JC Jr, Roth RA. (1998). Construction and characterization of a conditionally active version of the serine/threonine kinase Akt. J Biol Chem, 273(19), 11937-43.
8.                  Summers SA, Lipfert L, Birnbaum MJ. (1998). Polyoma middle T antigen activates the Ser/Thr kinase Akt in a PI3-kinase-dependent manner. Biochem Biophys Res Commun, 246(1), 76-81.
9.                  Zhou H, Summers SA, Birnbaum MJ, Pittman RN. (1998). Inhibition of Akt kinase by cell-permeable ceramide and its implications for ceramide-induced apoptosis. J Biol Chem, 273(26), 16568-75.
10.              Summers SA, Garza LA, Zhou H, Birnbaum MJ. (1998). Regulation of insulin-stimulated glucose transporter GLUT4 translocation and Akt kinase activity by ceramide. Mol Cell Biol, 18(9), 5457-64.
11.              Kallen CB, Billheimer JT, Summers SA, Stayrook SE, Lewis M, Strauss JF 3rd. (1998). Steroidogenic acute regulatory protein (StAR) is a sterol transfer protein. J Biol Chem, 273(41), 26285-8.
12.              Summers SA, Kao AW, Kohn AD, Backus GS, Roth RA, Pessin JE, Birnbaum MJ. (1999). The role of glycogen synthase kinase 3beta in insulin-stimulated glucose metabolism. J Biol Chem, 274(25), 17934-40.
13.              Summers SA, Yin VP, Whiteman EL, Garza LA, Cho H, Tuttle RL, Birnbaum MJ. (1999). Signaling pathways mediating insulin-stimulated glucose transport. Ann N Y Acad Sci, 892, 169-86.
14.              Summers SA, Whiteman EL, Cho H, Lipfert L, Birnbaum MJ. (1999). Differentiation-dependent suppression of platelet-derived growth factor signaling in cultured adipocytes. J Biol Chem, 274(34), 23858-67.
15.              Hausdorff SF, Fingar DC, Morioka K, Garza LA, Whiteman EL, Summers SA, Birnbaum MJ. (1999). Identification of wortmannin-sensitive targets in 3T3-L1 adipocytes. DissociationoOf insulin-stimulated glucose uptake and glut4 translocation. J Biol Chem, 274(35), 24677-84.
16.              Cass LA, Summers SA, Prendergast GV, Backer JM, Birnbaum MJ, Meinkoth JL. (1999). Protein kinase A-dependent and -independent signaling pathways contribute to cyclic AMP-stimulated proliferation. Mol Cell Biol, 19(9), 5882-91.
17.              Summers SA, Whiteman EL, Birnbaum MJ. (2000). Insulin signaling in the adipocyte. Int J Obes Relat Metab Disord, 24 Suppl 4, S67-70.
18.              Stratford S, DeWald DB, Summers SA. (2001). Ceramide dissociates 3'-phosphoinositide production from pleckstrin homology domain translocation. Biochem J, 354(Pt 2), 359-68.
19.              Ho RC, Davy KP, Hickey MS, Summers SA, Melby CL. (2002). Behavioral, metabolic, and molecular correlates of lower insulin sensitivity in Mexican-Americans. Am J Physiol Endocrinol Metab, 283(4), E799-808.
20.              Hoehn KL, Summers SA. (2003). Assaying AKT/protein kinase B activity. Methods Mol Med, 83, 137-44.
21.              Wang LP, Summers SA. (2003). Measuring insulin-stimulated phosphatidyl-inositol 3-kinase activity. Methods Mol Med, 83, 127-36.
22.              Chavez JA, Knotts TA, Wang LP, Li G, Dobrowsky RT, Florant GL, Summers SA. (2003). A role for ceramide, but not diacylglycerol, in the antagonism of insulin signal transduction by saturated fatty acids. J Biol Chem, 278(12), 10297-303.
23.              Chavez JA, Summers SA. (2003). Characterizing the effects of saturated fatty acids on insulin signaling and ceramide and diacylglycerol accumulation in 3T3-L1 adipocytes and C2C12 myotubes. Arch Biochem Biophys, 419(2), 101-9.
24.              Hoehn KL, Hudachek SF, Summers SA, Florant GL. (2004). Seasonal, tissue-specific regulation of Akt/protein kinase B and glycogen synthase in hibernators. Am J Physiol Regul Integr Comp Physiol, 286(3), R498-504.
25.              Stratford S, Hoehn KL, Liu F, Summers SA. (2004). Regulation of insulin action by ceramide: dual mechanisms linking ceramide accumulation to the inhibition of Akt/protein kinase B. J Biol Chem, 279(35), 36608-15.
26.              Florant GL, Porst H, Peiffer A, Hudachek SF, Pittman C, Summers SA, Rajala MW, Scherer PE. (2004). Fat-cell mass, serum leptin and adiponectin changes during weight gain and loss in yellow-bellied marmots (Marmota flaviventris). J Comp Physiol [B], 174(8), 633-9.
27.              Safadi-Chamberlain F, Wang LP, Payne SG, Lim CU, Stratford S, Chavez JA, Fox MH, Spiegel S, Summers SA. (2005). Effect of a membrane-targeted sphingosine kinase 1 on cell proliferation and survival. Biochem J, 388(Pt 3), 827-34.
28.              Summers SA, Nelson DH. (2005). A role for sphingolipids in producing the common features of type 2 diabetes, metabolic syndrome X, and Cushing's syndrome. Diabetes, 54(3), 591-602.
29.              Chavez JA, Holland WL, Bar J, Sandhoff K, Summers SA. (2005). Acid ceramidase overexpression prevents the inhibitory effects of saturated fatty acids on insulin signaling. J Biol Chem, 280(20), 20148-53.
30.              Summers SA. (2006). Ceramides in insulin resistance and lipotoxicity. Prog Lipid Res, 45(1), 42-72.
31.              Hoehn, KL., Holland, WL, Knotts, TA, Summers SA. (2006). The Etiology of Obesity-Induced Insulin Resistance. In George T. Ulrig (Ed.), Progress in Metabolic Syndrome Research (pp. 37-73). Hauppauge, NY: Nova Science Publishers, Inc.
32.              Arbiser JL, Kau T, Konar M, Narra K, Ramchandran R, Summers SA, Vlahos CJ, Ye K, Perry BN, Matter W, Fischl A, Cook J, Silver PA, Bain J, Cohen P, Whitmire D, Furness S, Govindarajan B, Bowen JP. (2007). Solenopsin, the alkaloidal component of the fire ant (Solenopsis invicta), is a naturally occurring inhibitor of phosphatidylinositol-3-kinase signaling and angiogenesis. Blood, 109(2), 560-5.
33.              Holland WL, Knotts TA, Chavez JA, Wang LP, Hoehn KL, Summers SA. (2007). Lipid mediators of insulin resistance. Nutr Rev, 65(6 Pt 2), S39-46.
34.              Holland WL, Brozinick JT, Wang LP, Hawkins ED, Sargent KM, Liu Y, Narra K, Hoehn KL, Knotts TA, Siesky A, Nelson DH, Karathanasis SK, Fontenot GK, Birnbaum MJ, Summers SA. (2007). Inhibition of ceramide synthesis ameliorates glucocorticoid-, saturated-fat-, and obesity-induced insulin resistance. Cell Metab, 5(3), 167-79.
35.              Holland, WL and Summers SA. (2008) Sphingolipids in insulin resistance and metabolic disease:  New insight from in vivo manipulation of sphingolipid synthesis.  Endocrine Reviews 29(4), 381–402.
36.              Fujii N, Ho RC, Manabe Y, Jessen N, Toyoda T, Holland WL, Summers SA, Hirshman MF, Goodyear LJ. (2008) Ablation of AMP-activated Protein Kinasea2 Activity Exacerbates Insulin Resistance Induced by High-fat Feeding of Mice.  Diabetes 57(11), 2958-66.
37.              Chavez, JA and Summers, SA (2009) Lipid Oversupply, Selective Insulin Resistance, and Lipotoxicity: Molecular Mechanisms.  Biochemica Biophysica Acta (in press)
38.              Bikman, B. and Summers, SA (2009) Ceramides and Hepatic Steatosis.  In Ashley Cowert (Ed.), Sphignolipids and Metabolic Disease.  Landes Bioscience.  (in press)
 
Printer Friendly Page Send this Story to a Friend
Disclaimer      Duke & Your Privacy      © 2009, Duke University Health System  
DHTS Strategic Web Services DHTS STRATEGIC WEB SERVICES