We have continued our studies of the insulin-like growth factors (IGFs), their receptors and binding proteins to understand the physiological and pathological role of the IGFS. During the past year we have demonstrated that: (1) adult rat serum contains a growth hormone dependent, glycosylated IGFbinding protein (IGFBP-3), and nonglycosylated binding proteins of 30 and 24 kDa; (2) the main binding protein in fetal rat serum is IGFBP-2, which is not present in adult rat serum; (3) IGFBP-2 mRNA is expressed in all fetal rat tissues, with highest levels in liver, followed by brain and stomach. In adult rats, IGFBP-2 mRNA levels are lower in liver and other tissues, but not in brain; (4) IGFBP-L mRNA also is predominantly expressed in fetal liver, and is decreased in adult liver. Levels in fetal kidney and brain are significantly lower than IGFBP-2 mRNA; (5) IGFBP-2 mRNA is localized to the choroid plexus in adult rat brain, and IGFBP-2 is the major IGF binding protein in rat cerebrospinal fluid; (6) In the brain of midgestational rat embryos, IGFBP-2 mRNA is expressed in the choroid plexus epithelium, the progenitor of the posterior pituitary, and the floor plate. IGF-H mRNA is expressed in some adjacent cells (the choroid mesenchyme and progenitors of the anterior and intermediate lobes of the pituitary), but not in the floor plate; (7) IGFBP-2 was identified in a human rhabdomyosarcoma cell line and in human cerebrospinal fluid; (8) In adult rat liver, IGFBP-2 mRNA is increased 10-fold after hypophysectomy, fasting, or streptozotocin diabetes; IGFBP-L mRNA is not increased after hypophysectomy, is increased after prolonged fasting, and is increased 100-fold in diabetes; (9) In a rat hepatoma cell line, dexamethasone increases IGFBP- I gene transcription; (1 0) IGF-II is an autocrine growth factor for a human neuroblastoma cell line, and acts via the IGF-I receptor; (I 1) IGF-I stimulates motility of a human melanoma cell Ene via the IGF-I receptor.

Project Start
Project End
Budget Start
Budget End
Support Year
17
Fiscal Year
1990
Total Cost
Indirect Cost
City
State
Country
United States
Zip Code
Adams, Ted D; Davidson, Lance E; Litwin, Sheldon E et al. (2017) Weight and Metabolic Outcomes 12 Years after Gastric Bypass. N Engl J Med 377:1143-1155
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Wasmund, Stephen L; Owan, Theophilus; Yanowitz, Frank G et al. (2011) Improved heart rate recovery after marked weight loss induced by gastric bypass surgery: two-year follow up in the Utah Obesity Study. Heart Rhythm 8:84-90
Hunt, Steven C; Hasstedt, Sandra J; Xin, Yuanpei et al. (2011) Polymorphisms in the NPY2R gene show significant associations with BMI that are additive to FTO, MC4R, and NPFFR2 gene effects. Obesity (Silver Spring) 19:2241-7
Benraouane, Fethi; Litwin, Sheldon E (2011) Reductions in cardiovascular risk after bariatric surgery. Curr Opin Cardiol 26:555-61
Adams, Ted D; Pendleton, Robert C; Strong, Michael B et al. (2010) Health outcomes of gastric bypass patients compared to nonsurgical, nonintervened severely obese. Obesity (Silver Spring) 18:121-30
Hammoud, Ahmad; Carrell, Douglas T; Meikle, A Wayne et al. (2010) An aromatase polymorphism modulates the relationship between weight and estradiol levels in obese men. Fertil Steril 94:1734-8

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