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Sample records for binding proteins igfbps

  1. The insulin-like growth factor-binding protein (IGFBP) superfamily.

    Science.gov (United States)

    Hwa, V; Oh, Y; Rosenfeld, R G

    1999-12-01

    Over the last decade, the concept of an IGFBP family has been well accepted, based on structural similarities and on functional abilities to bind IGFs with high affinities. The existence of other potential IGFBPs was left open. The discovery of proteins with N-terminal domains bearing striking structural similarities to the N terminus of the IGFBPs, and with reduced, but demonstrable, affinity for IGFs, raised the question of whether these proteins were "new" IGFBPs (22, 23, 217). The N-terminal domain had been uniquely associated with the IGFBPs and has long been considered to be critical for IGF binding. No other function has been confirmed for this domain to date. Thus, the presence of this important IGFBP domain in the N terminus of other proteins must be considered significant. Although these other proteins appear capable of binding IGF, their relatively low affinity and the fact that their major biological actions are likely to not directly involve the IGF peptides suggest that they probably should not be classified within the IGFBP family as provisionally proposed (22, 23). The conservation of this single domain, so critical to high-affinity binding of IGF by the six IGFBPs, in all of the IGFBP-rPs, as well, speaks to its biological importance. Historically, and perhaps, functionally, this has led to the designation of an "IGFBP superfamily". The classification and nomenclature for the IGFBP superfamily, are, of course, arbitrary; what is ultimately relevant is the underlying biology, much of which still remains to be deciphered. The nomenclature for the IGFBP related proteins was derived from a consensus of researchers working in the IGFBP field (52). Obviously, a more general consensus on nomenclature, involving all groups working on each IGFBP-rP, has yet to be reached. Further understanding of the biological functions of each protein should help resolve the nomenclature dilemma. For the present, redesignating these proteins IGFBP-rPs simplifies the

  2. Evolution of the insulin-like growth factor binding protein (IGFBP) family.

    Science.gov (United States)

    Daza, Daniel Ocampo; Sundström, Görel; Bergqvist, Christina A; Duan, Cunming; Larhammar, Dan

    2011-06-01

    The evolution of the IGF binding protein (IGFBP) gene family has been difficult to resolve. Both chromosomal and serial duplications have been suggested as mechanisms for the expansion of this gene family. We have identified and annotated IGFBP sequences from a wide selection of vertebrate species as well as Branchiostoma floridae and Ciona intestinalis. By combining detailed sequence analysis with sequence-based phylogenies and chromosome information, we arrive at the following scenario: the ancestral chordate IGFBP gene underwent a local gene duplication, resulting in a gene pair adjacent to a HOX cluster. Subsequently, the gene family expanded in the two basal vertebrate tetraploidization (2R) resulting in the six IGFBP types that are presently found in placental mammals. The teleost fish ancestor underwent a third tetraploidization (3R) that further expanded the IGFBP repertoire. The five sequenced teleost fish genomes retain 9-11 of IGFBP genes. This scenario is supported by the phylogenies of three adjacent gene families in the HOX gene regions, namely the epidermal growth factor receptors (EGFR) and the Ikaros and distal-less (DLX) transcription factors. Our sequence comparisons show that several important structural components in the IGFBPs are ancestral vertebrate features that have been maintained in all orthologs, for instance the integrin interaction motif Arg-Gly-Asp in IGFBP-2. In contrast, the Arg-Gly-Asp motif in IGFBP-1 has arisen independently in mammals. The large degree of retention of IGFBP genes after the ancient expansion of the gene family strongly suggests that each gene evolved distinct and important functions early in vertebrate evolution.

  3. Production of functional human insulin-like growth factor binding proteins (IGFBPs) using recombinant expression in HEK293 cells

    DEFF Research Database (Denmark)

    Wanscher, Anne Sofie Molsted; Williamson, Michael; Ebersole, Tasja Wainani;

    2015-01-01

    Insulin-like growth factor binding proteins (IGFBPs) display many functions in humans including regulation of the insulin-like growth factor (IGF) signaling pathway. The various roles of human IGFBPs make them attractive protein candidates in drug discovery. Structural and functional knowledge...... such as full-length human IGFBPs, still remains a challenge. Here we present a mammalian HEK293 expression method suitable for over-expression of secretory full-length human IGFBP-1 to -7. Protein purification of full-length human IGFBP-1, -2, -3 and -5 was conducted using a two-step chromatography procedure...

  4. Insulin-like growth factors (IGF-I, free IGF-I and IGF-II) and insulin-like growth factor binding proteins (IGFBP-2, IGFBP-3, IGFBP-6, and ALS) in blood circulation

    DEFF Research Database (Denmark)

    Yu, Hao; Mistry, J; Nicar, M J

    1999-01-01

    Insulin-like growth factors (IGFs) and IGF binding proteins (IGFBPs) play an important role in cell growth and differentiation. Clinical and epidemiological studies have indicated that measuring IGFs and IGFBPs in blood has potential implications in assessing growth-related abnormalities and risks...... of certain types of cancer. To facilitate the application, we reported a large collection of reference ranges of IGFs and IGFBPs in normal population and evaluations of these molecules in serum and plasma as well as the impact of freeze-thaw cycles on the measurement. IGF-I, IGFBP-3 andALS showed a similar...

  5. Peri/nuclear localization of intact insulin-like growth factor binding protein-2 and a distinct carboxyl-terminal IGFBP-2 fragment in vivo

    NARCIS (Netherlands)

    Hoeflich, A; Reisinger, R; Schuett, BS; Elmlinger, MW; Russo, VC; Vargas, GA; Jehle, PM; Lahm, H; Renner-Muller, [No Value; Wolf, E

    2004-01-01

    Insulin-like growth factor binding protein-2 (IGFBP-2) as one of the most important IGFBPs has never been assessed in the intracellular compartment in vivo. Since there is evidence for novel intracellular functions of distinct IGFBPs, we investigated the presence of IGFBP-2 inside the cell. In

  6. Peri/nuclear localization of intact insulin-like growth factor binding protein-2 and a distinct carboxyl-terminal IGFBP-2 fragment in vivo

    NARCIS (Netherlands)

    Hoeflich, A; Reisinger, R; Schuett, BS; Elmlinger, MW; Russo, VC; Vargas, GA; Jehle, PM; Lahm, H; Renner-Muller, [No Value; Wolf, E

    2004-01-01

    Insulin-like growth factor binding protein-2 (IGFBP-2) as one of the most important IGFBPs has never been assessed in the intracellular compartment in vivo. Since there is evidence for novel intracellular functions of distinct IGFBPs, we investigated the presence of IGFBP-2 inside the cell. In peri/

  7. Insulin-like growth factor-binding protein-3 (IGFBP-3) blocks the effects of asthma by negatively regulating NF-κB signaling through IGFBP-3R-mediated activation of caspases.

    Science.gov (United States)

    Lee, Yong-Chul; Jogie-Brahim, Sherryline; Lee, Dae-Yeol; Han, Jinfeng; Harada, Aki; Murphy, Liam J; Oh, Youngman

    2011-05-20

    Insulin-like growth factor-binding protein-3 (IGFBP-3) is a multifunctional protein known for modulating mitogenic and metabolic actions of IGFs as well as exerting a variety of biological actions not involving IGFs. Here, we show that IGFBP-3 blocks specific physiological consequences of asthma in an IGF-independent manner in vitro and in vivo. IGFBP-3 treatment effectively reduced all physiological manifestations of asthma examined in vivo (airway hyper-responsiveness, cellular and pathological changes in bronchoalveolar lavage fluid and lung tissue, and expression of numerous proinflammatory molecules). These unique IGFBP-3 effects were further confirmed in IGFBP-3-transgenic mice, thus strengthening the notion of IGFBP-3 actions within the respiratory system. Using human epithelial cells, we demonstrated the following: 1) IGFBP-3 blocks TNF-α-induced expression of proinflammatory molecules; 2) IGFBP-3 attenuates the TNF-α-induced migratory response of eosinophils; and 3) IGFBP-3 negatively regulates TNF-α-induced expression of the key NF-κB regulatory molecules IκBα and p65-NF-κB at the post-translational level. We identified that IGFBP-3 degrades IκBα and p65-NF-κB proteins through IGFBP-3 receptor (IGFBP-3R)-mediated activation of caspases thereby inhibiting TNF-α-induced activation of NF-κB signaling cascades. This unique IGFBP-3/IGFBP-3R action was further confirmed by demonstrating complete inhibition of IGFBP-3 action in the presence of caspase inhibitors as well as IGFBP-3R siRNAs. Non-IGF-binding IGFBP-3 mutants further proved the IGF-independent action of IGFBP-3. Our findings indicate that IGFBP-3 inhibits airway inflammation and hyper-responsiveness via an IGF-independent mechanism that involves activation of IGFBP-3R signaling and cross-talk with NF-κB signaling. The IGFBP-3/IGFBP-3R system therefore plays a pivotal role in the pathogenesis of asthma and can serve as a newly identified potential therapeutic target for this debilitating

  8. Effects of an endurance cycling competition on resting serum insulin-like growth factor I (IGF-I) and its binding proteins IGFBP-1 and IGFBP-3

    Science.gov (United States)

    Chicharro, J; Lopez-Calderon, A; Hoyos, J; Martin-Velasco, A; Villa, G; Villanua, M; Lucia, A

    2001-01-01

    Objectives—To determine whether consecutive bouts of intense endurance exercise over a three week period alters serum concentrations of insulin-like growth factor I (IGF-I) and/or its binding proteins. Methods—Seventeen professional cyclists (mean (SEM) VO2MAX, 74.7 (2.1) ml/kg/min; age, 27 (1) years) competing in a three week tour race were selected as subjects. Blood samples were collected at each of the following time points: t0 (control, before the start of competition), t1 (end of first week), and t3 (end of third week). Serum levels of both total and free IGF-I and IGF binding proteins 1 and 3 (IGFBP-1 and IGFBP-3) were measured in each of the samples. Cortisol levels were measured in nine subjects. Results—A significant (p<0.01) increase was found in total IGF-I and IGFBP-1 at both t1 and t3 compared with to (IGF-I: 110.9 (17.7), 186.8 (12.0), 196.9 (14.7) ng/ml at t0, t1, and t3 respectively; IGFBP-1: 54.6 (6.6), 80.6 (8.0), and 89.2 (7.9) ng/ml at t0, t1, and t3 respectively). A significant (p<0.01) decrease was noted in free IGF-I at t3 compared with both to and t1 (t0: 0.9 (0.1) ng/ml; t1: 0.9 (0.1) ng/ml; t3: 0.7 (0.1) ng/ml); in contrast, IGFBP-3 levels remained stable throughout the race. Conclusions—It would appear that the increase in circulating levels of both IGF-I and its binding protein IGFBP-1 is a short term (one week) endocrine adaptation to endurance exercise. After three weeks of training, total IGF-I and IGFBP-1 remained stable, whereas free IGF-I fell below starting levels. Key Words: cycling; insulin-like growth factor; exercise; endurance; binding proteins PMID:11579061

  9. Insulin-like growth factor-binding protein-5 (IGFBP-5) inhibits TNF-{alpha}-induced NF-{kappa}B activity by binding to TNFR1

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Jae Ryoung; Huh, Jae Ho; Lee, Yoonna; Lee, Sang Il [Molecular Therapy Research Center, Sungkyunkwan University, Seoul 135-710 (Korea, Republic of); Rho, Seung Bae [Research Institute, National Cancer Center, Goyang-si, Gyeonggi-do 411-769 (Korea, Republic of); Lee, Je-Ho, E-mail: jeholee@gmail.com [Molecular Therapy Research Center, Sungkyunkwan University, Seoul 135-710 (Korea, Republic of); Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2011-02-25

    Research highlights: {yields} Binding assays demonstrated that secreted- and cellular-IGFBP-5 interacted with TNFR1. {yields} The interaction between IGFBP-5 and TNFR1 was inhibited by TNF-{alpha} and was blocked TNF-{alpha}-activated NF-{kappa}B activity. {yields} IGFBP-5 interacted with TNFR1 through its N- and L-domains but the binding of L-domain to TNFR1 was blocked by TNF-{alpha}. {yields} Competition between the L-domain of IGFBP-5 and TNF-{alpha} blocked TNF-{alpha}-induced NF-{kappa}B activity. {yields} This study suggests that the L-domain of IGFBP-5 is a novel TNFR1 ligand that functions as a competitive TNF-{alpha} inhibitor. -- Abstract: IGFBP-5 is known to be involved in various cell phenomena such as proliferation, differentiation, and apoptosis. However, the exact mechanisms by which IGFBP-5 exerts its functions are unclear. In this study, we demonstrate for the first time that IGFBP-5 is a TNFR1-interacting protein. We found that ectopic expression of IGFBP-5 induced TNFR1 gene expression, and that IGFBP-5 interacted with TNFR1 in both an in vivo and an in vitro system. Secreted IGFBP-5 interacted with GST-TNFR1 and this interaction was blocked by TNF-{alpha}, demonstrating that IGFBP-5 might be a TNFR1 ligand. Furthermore, conditioned media containing secreted IGFBP-5 inhibited PMA-induced NF-{kappa}B activity and IL-6 expression in U-937 cells. Coimmunoprecipitation assays of TNFR1 and IGFBP-5 wild-type and truncation mutants revealed that IGFBP-5 interacts with TNFR1 through its N- and L-domains. However, only the interaction between the L-domain of IGFBP-5 and TNFR1 was blocked by TNF-{alpha} in a dose-dependent manner, suggesting that the L-domain of IGFBP-5 can function as a TNFR1 ligand. Competition between the L-domain of IGFBP-5 and TNF-{alpha} resulted in inhibition of TNF-{alpha}-induced NF-{kappa}{Beta} activity. Taken together, our results suggest that the L-domain of IGFBP-5 is a novel TNFR1 ligand that functions as a competitive TNF

  10. Nutritional status and growth hormone regulate insulin-like growth factor binding protein (igfbp) transcripts in Mozambique tilapia.

    Science.gov (United States)

    Breves, Jason P; Tipsmark, Christian K; Stough, Beth A; Seale, Andre P; Flack, Brenda R; Moorman, Benjamin P; Lerner, Darren T; Grau, E Gordon

    2014-10-01

    Growth in teleosts is controlled in large part by the activities of the growth hormone (Gh)/insulin-like growth factor (Igf) system. In this study, we initially identified igf-binding protein (bp)1b, -2b, -4, -5a and -6b transcripts in a tilapia EST library. In Mozambique tilapia (Oreochromis mossambicus), tissue expression profiling of igfbps revealed that igfbp1b and -2b had the highest levels of expression in liver while igfbp4, -5a and -6b were expressed at comparable levels in most other tissues. We compared changes in hepatic igfbp1b, -2b and -5a expression during catabolic conditions (28days of fasting) along with key components of the Gh/Igf system, including plasma Gh and Igf1 and hepatic gh receptor (ghr2), igf1 and igf2 expression. In parallel with elevated plasma Gh and decreased Igf1 levels, we found that hepatic igfbp1b increased substantially in fasted animals. We then tested whether systemic Gh could direct the expression of igfbps in liver. A single intraperitoneal injection of ovine Gh into hypophysectomized tilapia specifically stimulated liver igfbp2b expression along with plasma Igf1 and hepatic ghr2 levels. Our collective data suggest that hepatic endocrine signaling during fasting may involve post-translational regulation of plasma Igf1 via a shift towards the expression of igfbp1b. Thus, Igfbp1b may operate as a molecular switch to restrict Igf1 signaling in tilapia; furthermore, we provide new details regarding isoform-specific regulation of igfbp expression by Gh.

  11. Generation of antisera to mouse insulin-like growth factor binding proteins (IGFBP)-1 to -6: comparison of IGFBP protein and messenger ribonucleic acid localization in the mouse embryo

    NARCIS (Netherlands)

    M. van Kleffens (Marjolein); C.A.H. Groffen; N.F. Dits (Natasja); D.J. Lindenbergh-Kortleve (Dicky); A.G.P. Schuller (Alwin); S.L. Bradshaw; J.E. Pintar; E.C. Zwarthoff (Ellen); S.L.S. Drop (Stenvert); J.W. van Neck (Han)

    1999-01-01

    textabstractThe insulin-like growth factor (IGF) system is an important regulator of fetal growth and differentiation. IGF bioavailability is modulated by IGF binding proteins (IGFBPs). We have generated six different antisera, directed to synthetic peptide fragments of

  12. INSULIN-LIKE-GROWTH-FACTOR-BINDING-PROTEIN-3 (IGFBP-3) CONTRASTS MELANOMA PROGRESSION IN VITRO AND IN VIVO

    OpenAIRE

    ABBATE, FRANCO

    2014-01-01

    Our previous studies, revealed a dramatic degradation of the circulating IGF binding protein-3, one of the major regulators of IGF1, in the sera of patients affected by the IV stage of melanoma. For this reason, we focused on understanding the relation between IGFBP3 and melanoma cells. In "in vitro" experiments we found that the addition of exogenous IGFBP3 to the growth medium of metastatic melanoma cells is able to reduce their migratory and invasive potential. At the molecular level, t...

  13. Identification and localization of insulin-like growth factor-binding protein (IGFBP) messenger RNAs in human hair follicle dermal papilla.

    Science.gov (United States)

    Batch, J A; Mercuri, F A; Werther, G A

    1996-03-01

    The role of the insulin-like growth factors (IGFs) in hair follicle biology has recently been recognized, although their actions, sites of production, and modulation by the insulin-like growth factor-binding proteins (IGFBPs) have not to date been defined. IGF-I is essential for normal hair growth and development, and may be important in regulation of the hair growth cycle. In many culture systems, IGF-I actions are modulated by the IGFBPs. Thus, if IGFBPs are produced in the human hair follicle, they may play a role in targeting IGF-I to its receptor or may modulate IGF-I action by interaction with matrix proteins. We have used in situ hybridization to localize messenger RNA for the six IGFBPs in anagen hair follicles. Anti-sense and sense RNA probes for the IGFBPs (IGFBP-1 to -6) were produced, and 5-micrometer sections of adult facial skin were probed. Messenger RNA for IGFBP-3, -4, and -5 were identified, with predominantly IGFBP-3 and -5 mRNA found in the dermal papilla, and to a lesser extent IGFBP-4 mRNA. IGFBP-4 mRNA was also found at the dermal papilla/epithelial matrix border. Messenger RNAs for both IGFBP-4 and -5 were also demonstrated in the dermal sheath surrounding the hair follicle. Messenger RNAs for IGFBP-1, -2, and -6 were not identified. These studies demonstrate specific localization of IGFBP mRNAs in hair follicles, suggesting that they each play specific roles in the local modulation of IGF action during the hair growth cycle.

  14. Analysis of circulating insulin-like growth factor-1 (IGF-1 and IGF binding protein-3 (IGFBP-3 in tobacco smokers and non-smokers

    Directory of Open Access Journals (Sweden)

    Wilson RF

    2003-01-01

    Full Text Available Abstract Background IGF-1 and the major serum IGF-1 binding protein, IGFBP-3, are under extensive investigation as potential prognostic markers of specific malignancies and vascular diseases. However, there is conflicting evidence that tobacco smoking may influence systemic concentrations of IGF-1 and IGFBP-3. Subjects and methods Serum concentrations of IGF-1 and IGFBP-3 were measured in 20 smokers and 20 non-smokers, matched for age and gender. Serum concentrations of cotinine, the major metabolite of nicotine, and ICAM-1, known to exhibit a dose-dependent relationship with cotinine, were also assayed. Results There was no difference between the systemic concentrations of IGF-1 or IGFBP-3 found in smokers and non-smokers (IGF-1: mean [s.d]; 104 29 vs 101 24 ng ml-1, respectively; and IGFBP-3: 2562 [522] vs 2447 [570] ng ml-1, respectively. Similarly, there was no correlation between serum cotinine and IGF-1 or IGFBP-3 concentrations in smokers. Soluble ICAM-1 concentrations were significantly increased in smokers, compared to non-smokers (mean [s.d]; 258 [60] vs 194 [50] ng ml-1, respectively; p = 0.002. Conclusion There was no relationship noted between tobacco smoking and either IGF-1 or IGFBP-3. These data suggest that smoking would not appear to be a major confounder of the reported clinical associations between IGF-1, IGFBP-3, or IGF-1/IGFBP-3 ratios and specific disease entities.

  15. Hepatic insulin-like growth-factor binding protein (igfbp) responses tofood restriction in Atlantic salmon smolts

    Science.gov (United States)

    Breves, Jason P.; Phipps-Costin, Silas K.; Fujimoto, Chelsea K.; Einarsdottir, Ingibjörg E.; Regish, Amy M.; Björnsson, Björn Thrandur; McCormick, Stephen

    2016-01-01

    The growth hormone (Gh)/insulin-like growth-factor (Igf) system plays a central role in the regulation of growth in fishes. However, the roles of Igf binding proteins (Igfbps) in coordinating responses to food availability are unresolved, especially in anadromous fishes preparing for seaward migration. We assayed plasma Gh, Igf1, thyroid hormones and cortisol along with igfbp mRNA levels in fasted and fed Atlantic salmon ( Salmo salar ). Fish were fasted for 3 or 10 days near the peak of smoltification (late April to early May). Fasting reduced plasma glucose by 3 days and condition factor by 10 days. Plasma Gh, cortisol, and thyroxine (T 4 ) were not altered in response to fasting, whereas Igf1 and 3,5,3′-triiodo- l -thyronine (T 3 ) were slightly higher and lower than controls, respectively. Hepatic igfbp1b1 , - 1b2 , - 2a , - 2b1 and - 2b2 mRNA levels were not responsive to fasting, but there were marked increases in igfbp1a1 following 3 and 10 days of fasting. Fasting did not alter hepatic igf1or igf2 ; however, muscle igf1 was diminished by 10 days of fasting. There were no signs that fasting compromised branchial ionoregulatory functions, as indicated by unchanged Na + /K + -ATPase activity and ion pump/transporter mRNA levels. We conclude that dynamic hepatic igfbp1a1 and muscle igf1 expression participate in the modulation of Gh/Igf signaling in smolts undergoing catabolism.

  16. Use of the ligand immunofunctional assay for human insulin-like growth factor ((IGF) binding protein-3 (IGFBP-3) to analyze IGFBP-3 proteolysis and igf-i bioavailability in healthy adults, GH-deficient and acromegalic patients, and diabetics.

    Science.gov (United States)

    Lassarre, C; Duron, F; Binoux, M

    2001-05-01

    The ligand immunofunctional assay for plasma insulin-like growth factor (IGF) binding protein (IGFBP)-3 developed in our laboratory provides for specific measurement of intact, as opposed to proteolyzed, IGFBP-3. IGFBP-bound IGFs are dissociated and separated by acid pH ultrafiltration; thereafter, intact and proteolyzed IGFBP-3 are captured by a monoclonal antibody in a solid-phase assay and incubated with (125)I-IGF-I, which detects the intact protein but not its proteolytic fragments. This assay was combined with assays for IGF-I (RIA of the ultrafiltrate) and total IGFBP-3 (immunoradiometric assay) to quantify the percentage of proteolyzed IGFBP-3 (percent proteolyzed IGFBP-3) and to calculate the IGF-I/intact IGFBP-3 ratio as an index of the fraction of exchangeable IGF-I bound to IGFBP-3. This fraction represents most of the IGF-I that is bioavailable. Because GH and insulin control the hepatic production and plasma concentrations of IGF-I and IGFBP-3, we set out to determine whether variations in the secretion of the two hormones are involved in the regulation of IGFBP-3 proteolysis. The study included adult populations of 36 healthy subjects, 23 hypopituitary patients untreated with GH, 43 acromegalics (13 untreated), 42 insulin-treated type 1 diabetics [insulin-dependent diabetes mellitus (IDDM)] patients, and 50 type 2 diabetics [non-IDDM (NIDDM)] patients, 22 of whom were insulin-treated and the remaining 28 treated with sulfonylurea and/or metformin). Unlike IGF-I and (to a lesser extent) total IGFBP-3 levels, which decline with age, percent proteolyzed IGFBP-3 seemed relatively stable. In healthy adults, the mean +/- SEM was 29.4 +/- 1.9 for subjects less than 45 yr old and was slightly (but not significantly) lower, 25.7 +/- 3, for those of more than 45 yr. There was no difference between male and female subjects. In GH-deficient patients, despite severely depressed IGF-I levels, percent proteolyzed IGFBP-3 and IGF-I/intact IGFBP-3 ratios were within

  17. Eighteen Insulin-like Growth Factor (IGF) pathway genes, circulating levels of IGF-1 and its binding protein (IGFBP-3), and risk of prostate and breast cancer

    Science.gov (United States)

    Gu, Fangyi; Schumacher, Fredrick R.; Canzian, Federico; Allen, Naomi E.; Albanes, Demetrius; Berg, Christine D; Berndt, Sonja I.; Boeing, Heiner; Bueno-de-Mesquita, H. Bas; Buring, Julie E.; Chabbert-Buffet, Nathalie; Chanock, Stephen J.; Clavel-Chapelon, Françoise; Dumeaux, Vanessa; Gaziano, J. Michael; Giovannucci, Edward L.; Haiman, Christopher A.; Hankinson, Susan E.; Hayes, Richard B.; Henderson, Brian E.; Hunter, David J.; Hoover, Robert N.; Johansson, Mattias; Key, Timothy J.; Khaw, Kay-Tee; Kolonel, Laurence N.; Lagiou, Pagona; Lee, I-Min; LeMarchand, Loic; Lund, Eiliv; Ma, Jing; Onland-Moret, N. Charlotte; Overvad, Kim; Rodriguez, Laudina; Sacerdote, Carlotta; Sánchez, Maria-José; Stampfer, Meir J.; Stattin, Pär; Stram, Daniel O.; Thomas, Gilles; Thun, Michael J.; Tjønneland, Anne; Trichopoulos, Dimitrios; Tumino, Rosario; Virtamo, Jarmo; Weinstein, Stephanie J.; Willett, Walter C.; Yeager, Meredith; Zhang, Shumin M.; Kaaks, Rudolf; Riboli, Elio; Ziegler, Regina G.; Kraft, Peter

    2010-01-01

    Background Circulating levels of insulin-like growth factor I (IGF-1) and its main binding protein, IGF binding protein 3 (IGFBP-3), have been associated with risk of several types of cancer. Heritable factors explain up to 60% of the variation in IGF-1 and IGFBP-3 in studies of adult twins. Methods We systematically examined common genetic variation in 18 genes in the IGF signaling pathway for associations with circulating levels of IGF-1 and IGFBP-3. A total of 302 single nucleotide polymorphisms (SNPs) were genotyped in over 5500 Caucasian men and 5500 Caucasian women from the Breast and Prostate Cancer Cohort Consortium (BPC3). Results After adjusting for multiple testing, SNPs in the IGF1 and SSTR5 genes were significantly associated with circulating IGF-1 (p<2.1×10−4); SNPs in the IGFBP3 and IGFALS genes were significantly associated with circulating IGFBP-3. Multi-SNP models explained R2=0.62% of the variation in circulating IGF-1 and 3.9% of the variation in circulating IGFBP-3. We saw no significant association between these multi-SNP predictors of circulating IGF-1 or IGFBP-3 and risk of prostate or breast cancers. Conclusion Common genetic variation in the IGF1 and SSTR5 genes appears to influence circulating IGF-1 levels, and variation in IGFBP3 and IGFALS appears to influence circulating IGFBP-3. However, these variants explain only a small percentage of the variation in circulating IGF-1 and IGFBP-3 in Caucasian men and women. Impact Further studies are needed to explore contributions from other genetic factors such as rare variants in these genes and variation outside of these genes. PMID:20810604

  18. Serum concentrations of free and total insulin-like growth factor-I, IGF binding proteins -1 and -3 and IGFBP-3 protease activity in boys with normal or precocious puberty

    DEFF Research Database (Denmark)

    Juul, A; Flyvbjerg, Allan; Frystyk, Jan

    1996-01-01

    Circulating IGF-I and IGF binding protein-3 (IGFBP-3) levels both increase in puberty where growth velocity is high. The amount of free IGF-I is dependent on the IGF-I level and on the concentrations of the specific IGFBPs. Furthermore, IGFBP-3 proteolysis regulates the bioavailability of IGF......-I. However, the concentration of free IGF-I and possible IGFBP-3 proteolytic activity in puberty has not previously been studied....

  19. Effects of short-term caloric restriction on circulating free IGF-I, acid-labile subunit, IGF-binding proteins (IGFBPs)-1-4, and IGFBPs-1-3 protease activity in obese subjects

    DEFF Research Database (Denmark)

    Rasmussen, Michael Højby; Juul, Anders; Kjems, Lise Lund

    2006-01-01

    Decreased levels of GH and total IGF-I have been reported in obesity. It has been hypothesized that increased free (biologically active) IGF-I levels generated from IGF-binding protein (IGFBP) protease activity could be the mechanism for the low GH release in dieting obese subjects. However, no p...... a short-term very low-calorie diet (VLCD)....

  20. Variation in branchial expression among insulin-like growth-factor binding proteins (igfbps) during Atlantic salmon smoltification and seawater exposure

    Science.gov (United States)

    Breves, Jason P.; Fujimoto, Chelsea K.; Phipps-Costin, Silas K.; Einarsdottir, Ingibjörg E.; Björnsson, Björn Thrandur; McCormick, Stephen

    2017-01-01

    BackgroundIn preparation for migration from freshwater to marine habitats, Atlantic salmon (Salmo salar L.) undergo smoltification, a transformation that includes the acquisition of hyposmoregulatory capacity. The growth hormone (Gh)/insulin-like growth-factor (Igf) axis promotes the development of branchial ionoregulatory functions that underlie ion secretion. Igfs interact with a suite of Igf binding proteins (Igfbps) that modulate hormone activity. In Atlantic salmon smolts, igfbp4,−5a,−5b1,−5b2,−6b1 and−6b2 transcripts are highly expressed in gill. We measured mRNA levels of branchial and hepatic igfbps during smoltification (March, April, and May), desmoltification (July) and following seawater (SW) exposure in March and May. We also characterized parallel changes in a broad suite of osmoregulatory (branchial Na+/K+-ATPase (Nka) activity, Na+ /K + /2Cl − cotransporter 1 (nkcc1) and cystic fibrosis transmembrane regulator 1 (cftr1) transcription) and endocrine (plasma Gh and Igf1) parameters.ResultsIndicative of smoltification, we observed increased branchial Nka activity, nkcc1 and cftr1 transcription in May. Branchial igfbp6b1 and -6b2 expression increased coincidentally with smoltification. Following a SW challenge in March, igfbp6b1 showed increased expression while igfbp6b2 exhibited diminished expression. igfbp5a,−5b1 and−5b2 mRNA levels did not change during smolting, but each had lower levels following a SW exposure in March.ConclusionsSalmonids express an especially large suite of igfbps. Our data suggest that dynamic expression of particular igfbps accompanies smoltification and SW challenges; thus, transcriptional control of igfbps may provide a mechanism for the local modulation of Igf activity in salmon gill.

  1. Relevance of fruits, vegetables and flavonoids from fruits and vegetables during early life, mid-childhood and adolescence for levels of insulin-like growth factor (IGF-1) and its binding proteins IGFBP-2 and IGFBP-3 in young adulthood.

    Science.gov (United States)

    Krupp, Danika; Remer, Thomas; Penczynski, Katharina J; Bolzenius, Katja; Wudy, Stefan A; Buyken, Anette E

    2016-02-14

    The growth hormone (GH) insulin-like growth factor (IGF) axis has been linked to insulin metabolism and cancer risk. Experimental evidence indicates that the GH-IGF axis itself can be influenced by dietary flavonoids. As fruit and vegetable (FV) intake is a major source of flavonoid consumption, FV's beneficial health effects may be explained via flavonoids' influence on the GH-IGF axis, but observational evidence is currently rare. We used data from Dortmund Nutritional and Anthropometric Longitudinally Designed Study participants to analyse prospective associations between FV, fruit intake and flavonoid intake from FV (FlavFV) with IGF-1 and its binding proteins IGFBP-2 and IGFBP-3. Subjects needed to provide a fasting blood sample in adulthood (18-39 years) and at least two 3-d weighed dietary records in early life (0·5-2 years, n 191), mid-childhood (3-7 years, n 265) or adolescence (girls: 9-15 years, boys: 10-16 years, n 261). Additional analyses were conducted among those providing at least three 24-h urine samples in adolescence (n 236) to address the predictor urinary hippuric acid (HA), a biomarker of polyphenol intake. Higher fruit intake in mid-childhood and adolescence was related to higher IGFBP-2 in adulthood (P=0·03 and P=0·045). Comparable trends (P=0·045-0·09) were discernable for FV intake (but not FlavFV) in all three time windows. Similarly, higher adolescent HA excretion tended to be related (P=0·06) to higher adult IGFBP-2 levels. Regarding IGFBP-3, a marginal (P=0·08) positive association was observed with FlavFV in mid-childhood only. None of the investigated dietary factors was related to IGF-1. In conclusion, higher fruit and FV intakes during growth may be relevant for adult IGFBP-2, but probably not for IGFBP-3 or IGF-1.

  2. Concentrations, release, and disposal of insulin-like growth factor (IGF)-binding proteins (IGFBP), IGF-I, and growth hormone in different vascular beds in patients with cirrhosis

    DEFF Research Database (Denmark)

    Møller, S; Juul, A; Becker, U

    1995-01-01

    The liver is thought to be the major source of circulating insulin-like growth factor (IGF-I) and IGF-binding protein-1 (IGFBP-1), whereas the primary production site of circulating IGFBP-3 remains unknown. As other tissues may contribute to the circulating pool of IGF-I and IGFBP, the aim...... patients (6 +/- 2%; P pressure (r = -0.49; P

  3. Effects of quercetin on insulin-like growth factors (IGFs and their binding protein-3 (IGFBP-3 secretion and induction of apoptosis in human prostate cancer cells

    Directory of Open Access Journals (Sweden)

    Vijayababu Marati R

    2006-04-01

    Full Text Available Abstract Background Quercetin, the predominant flavonoid, has been reported to lower the risk of several cancers. This flavonoid found in onion, grapes, green vegetables, etc. has been shown to possess potent antiproliferative effects against various malignant cells. This study was designed to investigate its effects on insulin-like growth factors (IGFs and their binding protein-3 (IGFBP-3 proteins secretion and also apoptosis induction in the human prostate cancer cell line, PC-3. Methods We evaluated the secretion of IGF-I, -II and IGFBP-3 in quercetin treated cells by immunoradiometric (IRMA method. Apoptosis was studied in quercetin treated cells by TUNEL and DNA fragmentation. Protein expressions of Bcl-2, Bcl-xL, Bax and caspase-3 were studied by western blot. Results At a dose of 100 μM concentration, we observed increased IGFBP-3 accumulation in PC-3 cells conditioned medium with a dose dependent increase with 2 fold over a base line, and significantly reduced the both IGF-I and IGF-II levels. Apoptosis induction was also confirmed by TUNEL assay. Bcl-2 and Bcl-xL protein expressions were significantly decreased and Bax and caspase-3 were increased. Conclusion These results suggest that the decreased level of IGFs could be due to the increased levels of IGFBP-3, because of the high binding affinity towards IGFs, thereby decreasing the cell proliferation. The increased level of IGFBP-3 was associated with increased pro-apoptotic proteins and apoptosis in response to quercetin, suggesting it may be a p53-independent effector of apoptosis in prostate cancer cells.

  4. Insulin-like growth factor 2 (IGF2 ) and IGF-binding protein 1 (IGFBP1) gene variants are associated with overfeeding-induced metabolic changes.

    Science.gov (United States)

    Ukkola, O; Sun, G; Bouchard, C

    2001-12-01

    The aim of this study was to investigate the role of insulin-like growth factor 1 (IGF1), IGF2, IGF binding protein 1 (IGFBP1) and IGFBP3 gene variants on the metabolic changes observed in response to a 100-day overfeeding protocol conducted with 12 pairs of monozygotic twins. Genotyping was done by PCR-RFLP and DNA sequencer methods. Body fat measurements included hydrodensitometry and abdominal fat from computed tomography. Plasma glucose and insulin during fasting and in response to an OGTT were assayed. Plasma lipids were measured enzymatically. In response to caloric surplus, fasting plasma insulin (p < 0.05) and OGTT insulin (p = 0.004) but not glucose area, increased more among the subjects with IGF2 Apa I GG (n = 12) than those with AA + AG (n = 12). The changes were independent of changes in total fatness. The subjects with IGFBP1 Bgl II AA (n = 8) showed greater increases in abdominal visceral fat (p < 0.01), OGTT insulin area (p = 0.05) and total cholesterol (p < 0.03) with overfeeding than the subjects with AG + GG (n = 16). IGFBP3 Nde I and the IGF1 (CT)n markers were not associated with responsiveness to overfeeding. Insulin sensitivity decreased in the subjects with IGF2 Apa I GG and the subjects with IGFBP1 Bgl II AA showed an accumulation of abdominal visceral fat and the early symptoms of the metabolic syndrome after long-term caloric surplus. Genetic variation at the IGF2 and IGFBP1 loci could be among the factors responsible for the inter-individual differences observed in the response to long-term alterations in energy balance and should be further investigated in larger cohorts.

  5. Urinary Tissue Inhibitor of Metalloproteinase-2 (TIMP-2 • Insulin-Like Growth Factor-Binding Protein 7 (IGFBP7 Predicts Adverse Outcome in Pediatric Acute Kidney Injury.

    Directory of Open Access Journals (Sweden)

    Jens H Westhoff

    Full Text Available The G1 cell cycle inhibitors tissue inhibitor of metalloproteinase-2 (TIMP-2 and insulin-like growth factor-binding protein 7 (IGFBP7 have been identified as promising biomarkers for the prediction of adverse outcomes including renal replacement therapy (RRT and mortality in critically ill adult patients who develop acute kidney injury (AKI. However, the prognostic value of urinary TIMP-2 and IGFBP7 in neonatal and pediatric AKI for adverse outcome has not been investigated yet.The product of the urinary concentration of TIMP-2 and IGFBP7 ([TIMP-2]•[IGFBP7] was assessed by a commercially available immunoassay (NephroCheck™ in a prospective cohort study in 133 subjects aged 0-18 years including 46 patients with established AKI according to pRIFLE criteria, 27 patients without AKI (non-AKI group I and 60 apparently healthy neonates and children (non-AKI group II. AKI etiologies were: dehydration/hypovolemia (n = 7, hemodynamic instability (n = 7, perinatal asphyxia (n = 9, septic shock (n = 7, typical hemolytic-uremic syndrome (HUS; n = 5, interstitial nephritis (n = 5, vasculitis (n = 4, nephrotoxic injury (n = 1 and renal vein thrombosis (n = 1.When AKI patients were classified into pRIFLE criteria, 6/46 (13% patients fulfilled the criteria for the category "Risk", 13/46 (28% for "Injury", 26/46 (57% for "Failure" and 1/46 (2% for "Loss". Patients in the "Failure" stage had a median 3.7-fold higher urinary [TIMP-2]•[IGFBP7] compared to non-AKI subjects (P<0.001. When analyzed for AKI etiology, highest [TIMP-2]•[IGFBP7] values were found in patients with septic shock (P<0.001 vs. non-AKI I+II. Receiver operating characteristic (ROC curve analyses in the AKI group revealed good performance of [TIMP-2]•[IGFBP7] in predicting 30-day (area under the curve (AUC 0.79; 95% CI, 0.61-0.97 and 3-month mortality (AUC 0.84; 95% CI, 0.67-0.99 and moderate performance in predicting RRT (AUC 0.67; 95% CI, 0.50-0.84.This study shows that urinary [TIMP

  6. Cellular proliferation rate and insulin-like growth factor binding protein (IGFBP)-2 and IGFBP-3 and estradiol receptor alpha expression in the mammary gland of dairy heifers naturally infected with gastrointestinal nematodes during development.

    Science.gov (United States)

    Perri, A F; Dallard, B E; Baravalle, C; Licoff, N; Formía, N; Ortega, H H; Becú-Villalobos, D; Mejia, M E; Lacau-Mengido, I M

    2014-01-01

    Mammary ductal morphogenesis during prepuberty occurs mainly in response to insulin-like growth factor-1 (IGF-1) and estradiol stimulation. Dairy heifers infected with gastrointestinal nematodes have reduced IGF-1 levels, accompanied by reduced growth rate, delayed puberty onset, and lower parenchyma-stroma relationship in their mammary glands. Immunohistochemical studies were undertaken to determine variations in cell division rate, IGF-1 system components, and estradiol receptors (ESR) during peripubertal development in the mammary glands of antiparasitic-treated and untreated Holstein heifers naturally infected with gastrointestinal nematodes. Mammary biopsies were taken at 20, 30, 40, and 70 wk of age. Proliferating cell nuclear antigen immunolabeling, evident in nuclei, tended to be higher in the parenchyma of the glands from treated heifers than in those from untreated. Insulin-like growth factor binding proteins (IGFBP) type 2 and type 3 immunolabeling was cytoplasmic and was evident in stroma and parenchyma. The IGFBP2-labeled area was lower in treated than in untreated heifers. In the treated group, a maximal expression of this protein was seen at 40 wk of age, whereas in the untreated group the labeling remained constant. No differences were observed for IGFBP3 between treatment groups or during development. Immunolabeling for α ESR (ESR1) was evident in parenchymal nuclei and was higher in treated than in untreated heifers. In the treated group, ESR1 peaked at 30 wk of age and then decreased. These results demonstrate that the parasite burden in young heifers negatively influence mammary gland development, affecting cell division rate and parameters related to estradiol and IGF-1 signaling in the gland.

  7. Differential effects of insulin-like growth factor binding protein-6 (IGFBP-6 on migration of two ovarian cancer cell lines

    Directory of Open Access Journals (Sweden)

    Zhiyong eYang

    2015-01-01

    Full Text Available IGFBP-6 inhibits angiogenesis as well as proliferation and survival of rhabdomyosarcoma cells. However, it promotes migration of these cells in an IGF-independent manner. The IGF system is implicated in ovarian cancer, so we studied the effects of IGFBP-6 in ovarian cancer cells.Methods: The effects of wild type (wt and a non-IGF-binding mutant (m of IGFBP-6 on migration of HEY and SKOV-3 ovarian cancer cells, which respectively represent aggressive and transitional cancers, were studied. ERK and JNK phosphorylation were measured by Western blotting.Results: IGF-II, wt- and mIGFBP-6 each promoted SKOV3 cell migration by 77-98% (p<0.01. In contrast, IGF-II also increased HEY cell migration to 155 ± 13% of control (p<0.001, but wtIGFBP-6 and mIGFBP-6 decreased migration to 62 ± 5% and 66 ± 3% respectively (p<0.001. In these cells, coincubation of IGF-II with wt but not mIGFBP-6 increased migration. MAP kinase pathways are involved in IGFBP-6-induced rhabdomyosarcoma cell migration, so activation of these pathways in HEY and SKOV3 cells was studied. wt and mIGFBP-6 increased ERK phosphorylation by 62-99% in both cell lines (p<0.05. wtIGFBP-6 also increased JNK phosphorylation by 139-153% in both cell lines (p<0.05, but the effect of mIGFBP-6 was less clear. ERK and JNK inhibitors partially inhibited the migratory effects of wt and mIGFBP-6 in SKOV3 cells, whereas the ERK inhibitor partially restored wt and mIGFBP-6-induced inhibition of HEY cell migration. The JNK inhibitor had a lesser effect on the actions of wtIGFBP-6 and no effect on the actions of mIGFBP-6 in HEY cells.Conclusions: IGFBP-6 has opposing effects on migration of HEY and SKOV3 ovarian cancer cells, but activates MAP kinase pathways in both. Delineating the pathways underlying the differential effects on migration will increase our understanding of ovarian cancer metastasis and shed new light on the IGF-independent effects of IGFBP-6.

  8. Advanced glycosylation end products (AGEs), insulin-like growth factor-1 (IGF-1) and IGF-binding protein-3 (IGFBP-3) in patients with type 2 diabetes mellitus.

    Science.gov (United States)

    Garay-Sevilla, M E; Nava, L E; Malacara, J M; Wróbel, K; Wróbel, K; Pérez, U

    2000-01-01

    Advanced glycosylation end product (AGE) formation is a major mechanism for the development of complications in diabetes, and the possible roles of insulin-like growth factor 1 (IGF-1) and IGF binding protein 3 (IGFBP-3) are not clearly established. We examined the associations of AGEs, free IGF-I and IGFBP-3 in Type 2 diabetes mellitus (DM) patients under diverse conditions. In a cross-sectional design we studied 110 subjects (67 women and 43 men): non-diabetic controls in group 1, (n = 15) and diabetes patients as follows: group 2, without complications (n = 25); group 3, with chronic complications (n = 25); group 4, with acute or chronic infections (n = 24); group 5, hospitalized for reasons unrelated to diabetes (n = 9); group 6, with end-stage renal disease (ESRD) (n = 12). AGEs were determined by a spectrofluorometric method (HPLC). Insulin and IGFBP-3 were measured by RIA and free IGF-1 with an IRMA method. AGEs were 13-fold higher in patients with ESRD (p<0.001), and lower in healthy individuals. Free IGF-1 was lower in the patients with complications (p = 0.017), with infections (p = 0.006) and hospitalized (p = 0.04). IGFBP-3 was higher in hospitalized patients (p=0.017). AGEs were associated with free IGF-1 (r = 0.41, p = 0.04) in the group with complications, and with HbA(1c) (r = -0.90, p = 0.002) in hospitalized patients. In the total group, free IGF-1 (r = -0.25, p = 0.008), and IGFBP-3 (r = -0.22, p = 0.021) were associated with HbA(1c). We concluded that AGEs were markedly increased in diabetic patients with ESRD, IGF-1 was decreased in patients with infections and hospitalized, and was negatively associated with HbA(1c). IGFBP-3 was increased in hospitalized patients, with higher levels in patients with long bone fractures. A complex interaction of humoral factors may participate in the acceleration of complications of diabetes.

  9. Inhibition of human MCF-7 breast cancer cells and HT-29 colon cancer cells by rice-produced recombinant human insulin-like growth binding protein-3 (rhIGFBP-3.

    Directory of Open Access Journals (Sweden)

    Stanley C K Cheung

    Full Text Available BACKGROUND: Insulin-like growth factor binding protein-3 (IGFBP-3 is a multifunctional molecule which is closely related to cell growth, apoptosis, angiogenesis, metabolism and senescence. It combines with insulin-like growth factor-I (IGF-I to form a complex (IGF-I/IGFBP-3 that can treat growth hormone insensitivity syndrome (GHIS and reduce insulin requirement in patients with diabetes. IGFBP-3 alone has been shown to have anti-proliferation effect on numerous cancer cells. METHODOLOGY/PRINCIPAL FINDINGS: We reported here an expression method to produce functional recombinant human IGFBP-3 (rhIGFBP-3 in transgenic rice grains. Protein sorting sequences, signal peptide and endoplasmic reticulum retention tetrapeptide (KDEL were included in constructs for enhancing rhIGFBP-3 expression. Western blot analysis showed that only the constructs with signal peptide were successfully expressed in transgenic rice grains. Both rhIGFBP-3 proteins, with or without KDEL sorting sequence inhibited the growth of MCF-7 human breast cancer cells (65.76 ± 1.72% vs 45.00 ± 0.86%, p < 0.05; 50.84 ± 1.97% vs 45.00 ± 0.86%, p < 0.01 respectively and HT-29 colon cancer cells (65.14 ± 3.84% vs 18.01 ± 13.81%, p < 0.05 and 54.7 ± 9.44% vs 18.01 ± 13.81%, p < 0.05 respectively when compared with wild type rice. CONCLUSION/SIGNIFICANCE: These findings demonstrated the feasibility of producing biological active rhIGFBP-3 in rice using a transgenic approach, which will definitely encourage more research on the therapeutic use of hIGFBP-3 in future.

  10. Cloning and expression of full-length human insulin-like growth factor binding protein 3 (IGFBP3 in the Escherichia coli

    Directory of Open Access Journals (Sweden)

    Emad Khodadadi

    2015-01-01

    Conclusion: DNA fragment encoding the full-length IGFBP3 protein was accurately cloned in the pET-11a expression vector and the recombinant plasmid transformed to E. coli BL21 (DE3 expression host. Results of the SDS-PAGE analysis verified that recombinant IGFBP3 (31.6 kDa are successfully expressed under the control of T7 promoter. As we shown pET-11a can be successfully used for expression of the IGFBP3 protein.

  11. Genital skin fibroblasts (GF) of patients with androgen insensitivity syndrome express higher insulin-like growth factor binding protein (IGFBP)-2, -3 and -5 than GF of normally virilized males.

    Science.gov (United States)

    Diesing, D; Elmlinger, M W; Schuett, B S; Weidemann, W; Romalo, G; Schweikert, H U; Spindler, K-D; Ranke, M B

    2003-01-01

    We investigated the effects of androgens, estradiol (E2) and insulin-like growth factor (IGF)-I on IGF-II, insulin-like growth factor binding protein (IGFBP)-2, -3 and -5 and mRNA in genital fibroblasts (GF) from patients with complete androgen insensitivity (CAIS) and normally virilized males (C). Proteins were measured by specific RIA and Western ligand blot, and specific mRNA levels by RT-PCR normalized by GAPDH levels. Secretion of IGF-II was lowered in CAIS (pGF and by testosterone + IGF-I in C GF. Secretion of IGFBP-2 was higher (pGF and IGFBP-2 mRNA levels were increased by E2 in C GF (pGF. CAIS GF also secreted more IGFBP-3 (pGF (pGF, the availability of IGF-II in CAIS GF is apparently decreased by two facts: by the decreased expression and by increased expression of IGFBP-2, -3 and -5. Furthermore, E2 and IGF-I modulate the expression of IGF-II and IGFBP in GF. This may play a role in the failure to develop male external genitals in CAIS patients. Copyright 2003 S. Karger AG, Basel

  12. Urinary bladder cancer risk in relation to a single nucleotide polymorphism (rs2854744) in the insulin-like growth factor-binding protein-3 (IGFBP3) gene.

    Science.gov (United States)

    Selinski, Silvia; Lehmann, Marie-Louise; Blaszkewicz, Meinolf; Ovsiannikov, Daniel; Moormann, Oliver; Guballa, Christoph; Kress, Alexander; Truss, Michael C; Gerullis, Holger; Otto, Thomas; Barski, Dimitri; Niegisch, Günter; Albers, Peter; Frees, Sebastian; Brenner, Walburgis; Thüroff, Joachim W; Angeli-Greaves, Miriam; Seidel, Thilo; Roth, Gerhard; Volkert, Frank; Ebbinghaus, Rainer; Prager, Hans-Martin; Lukas, Cordula; Bolt, Hermann M; Falkenstein, Michael; Zimmermann, Anna; Klein, Torsten; Reckwitz, Thomas; Roemer, Hermann C; Hartel, Mark; Weistenhöfer, Wobbeke; Schöps, Wolfgang; Rizvi, S Adibul Hassan; Aslam, Muhammad; Bánfi, Gergely; Romics, Imre; Ickstadt, Katja; Hengstler, Jan G; Golka, Klaus

    2012-02-01

    Currently, twelve validated genetic variants have been identified that are associated with urinary bladder cancer (UBC) risk. However, those validated variants explain only 5-10% of the overall inherited risk. In addition, there are more than 100 published polymorphisms still awaiting validation or disproval. A particularly promising of the latter unconfirmed polymorphisms is rs2854744 that recently has been published to be associated with UBC risk. The [A] allele of rs2854744 has been reported to be associated with a higher promoter activity of the insulin-like growth factor-binding protein-3 (IGFBP3) gene, which may lead to increased IGFBP-3 plasma levels and cancer risk. Therefore, we investigated the association of rs2854744 with UBC in the IfADo case-control series consisting of 1,450 cases and 1,725 controls from Germany, Hungary, Venezuela and Pakistan. No significant association of rs2854744 with UBC risk was obtained (all study groups combined: unadjusted P = 0.4446; adjusted for age, gender and smoking habits P = 0.6510), besides a small effect of the [A] allele in the Pakistani study group opposed to the original findings (unadjusted P = 0.0508, odds ratio (OR) = 1.43 for the multiplicative model) that diminished after adjustment for age, gender and smoking habits (P = 0.7871; OR = 0.93). Associations of rs2854744 with occupational exposure to urinary bladder carcinogens and smoking habits were also not present. A meta-analysis of all available case-control series including the original discovery study resulted in an OR of 1.00 (P = 0.9562). In conclusion, we could not confirm the recently published hypothesis that rs2854744 in the IGFBP3 gene is associated with UBC risk.

  13. Insulin-like growth factor-binding protein-1 (IGFBP-1 in cervical secretions in women with symptoms of preterm delivery

    Directory of Open Access Journals (Sweden)

    Amra Habibović

    2008-08-01

    Full Text Available The aim of this prospective study was to investigate a value ofinsulin-like growth factor-binding protein-1 (IGFBP-1 in cervicalsecretion in women with symptoms of preterm delivery and correlatethis test to the Bishop Score in prediction of a preterm delivery.The study group included 30 pregnant women with singletonpregnancy between 24 – 34 gestational weeks who were hospitalizedbecause of a threatening preterm delivery with intact fetalmembranes. A positive Actim Partus test (concentration higherthan 10 µg/l and Bishop Score higher than 4 signify a risk of thepreterm delivery. The Bishop Score is a better predictor of the pretermdelivery in patients with symptoms of the preterm delivery.

  14. Insulin-Like Growth Factor Binding Protein 2 (IGFBP-2) Promotes Growth and Survival of Breast Epithelial Cells: Novel Regulation of the Estrogen Receptor

    National Research Council Canada - National Science Library

    Foulstone, Emily J; Zeng, Li; Perks, Claire M; Holly, Jeff M. P

    2013-01-01

    .... However, how IGFBP-2 contributes to the malignant state is still unclear. Silencing IGFBP-2 blocked cell proliferation and in MCF-7 cells increased cell death, indicating that IGFBP-2 was acting in both a mitogenic and a survival capacity...

  15. Serum levels of insulin-like growth factor (IGF)-binding protein-3 (IGFBP-3) in healthy infants, children, and adolescents

    DEFF Research Database (Denmark)

    Juul, A; Dalgaard, P; Blum, W F

    1995-01-01

    index (BMI), and pubertal stage. Therefore, we measured IGFBP-3, IGF-I, IGF-II, IGFBP-1, and IGFBP-2 levels by RIA in 907 healthy children to establish well characterized normative data on IGFBP-3 according to age, sex, and pubertal stage and to study the complex relationship between IGFs and their BPs...... growth velocity is high. Concomitantly, IGF-II and IGFBP-2 levels were unchanged throughout puberty, whereas IGFBP-1 levels declined with age in prepubertal children, with lowest values in puberty. There was a highly significant correlation between IGF-I and -II and IGFBP-3 on a molar basis (r = 0.84; P...

  16. Duplication of the IGFBP-2 gene in teleost fish: protein structure and functionality conservation and gene expression divergence.

    Directory of Open Access Journals (Sweden)

    Jianfeng Zhou

    Full Text Available BACKGROUND: Insulin-like growth factor binding protein-2 (IGFBP-2 is a secreted protein that binds and regulates IGF actions in controlling growth, development, reproduction, and aging. Elevated expression of IGFBP-2 is often associated with progression of many types of cancers. METHODOLOGY/PRINCIPAL FINDINGS: We report the identification and characterization of two IGFBP-2 genes in zebrafish and four other teleost fish. Comparative genomics and structural analyses suggest that they are co-orthologs of the human IGFBP-2 gene. Biochemical assays show that both zebrafish igfbp-2a and -2b encode secreted proteins that bind IGFs. These two genes exhibit distinct spatiotemporal expression patterns. During embryogenesis, IGFBP-2a mRNA is initially detected in the lens, then in the brain boundary vasculature, and subsequently becomes highly expressed in the liver. In the adult stage, liver has the highest levels of IGFBP-2a mRNA, followed by the brain. Low levels of IGFBP-2a mRNA were detected in muscle and in the gonad in male adults only. IGFBP-2b mRNA is detected initially in all tissues at low levels, but later becomes abundant in the liver. In adult males, IGFBP-2b mRNA is only detected in the liver. In adult females, it is also found in the gut, kidney, ovary, and muscle. To gain insights into how the IGFBP-2 genes may have evolved through partitioning of ancestral functions, functional and mechanistic studies were carried out. Expression of zebrafish IGFBP-2a and -2b caused significant decreases in the growth and developmental rates and their effects are comparable to that of human IGFBP-2. IGFBP-2 mutants with altered IGF binding-, RGD-, and heparin-binding sites were generated and their actions examined. While mutating the RGD and heparin binding sites had little effect, altering the IGF binding site abolished its biological activity. CONCLUSIONS/SIGNIFICANCE: These results suggest that IGFBP-2 is a conserved regulatory protein and it inhibits

  17. Mecasermin rinfabate: insulin-like growth factor-I/insulin-like growth factor binding protein-3, mecaserimin rinfibate, rhIGF-I/rhIGFBP-3.

    Science.gov (United States)

    2005-01-01

    Insmed is developing mecasermin rinfabate, a recombinant complex of insulin-like growth factor-I (rhIGF-I) and binding protein-3 (rhIGFBP-3) [insulin-like growth factor-I/insulin-like growth factor binding protein-3, rhIGF-I/rhIGFBP-3, SomatoKine], for a number of metabolic and endocrine indications. In the human body, IGF-I circulates in the blood bound to a binding protein-3 (IGFBP-3), which regulates the delivery of IGF-I to target tissues, and particular proteases clip them apart in response to stresses and release IGF-I as needed. IGF-I, a naturally occurring hormone, is necessary for normal growth and metabolism. For the treatment of IGF-I deficiency, it is desirable to administer IGF-I bound to IGFBP-3 to maintain the normal equilibrium of these proteins in the blood. Mecasermin rinfabate (rhIGF-I/rhIGFBP-3) mimics the effects of the natural protein complex in the bloodstream and would augment the natural supply of these linked compounds. The most advanced indication in development of mecasermin rinfabate is the treatment of severe growth disorders due to growth hormone insensitivity syndrome (GHIS), also called Laron syndrome. GHIS is a genetic condition in which patients do not produce adequate quantities of IGF because of a failure to respond to the growth hormone signal. This results in a slower growth rate and short stature. Mecasermin rinfabate also has potential as replacement therapy for IGF-I, which may become depleted in indications such as major surgery, organ damage/failure, traumatic injury, cachexia and severe burn trauma. It also has potential for the treatment of osteoporosis. Mecasermin rinfabate was developed by Celtrix using its proprietary recombinant protein production technology. Subsequently, Celtrix was acquired by Insmed Pharmaceuticals on 1 June 2000. Insmed and Avecia of the UK have signed an agreement for manufacturing mecasermin rinfabate and its components, rhIGF-1 and rhIGFBP-3. CGMP clinical production of mecasermin rinfabate

  18. Insulin-like growth factor binding proteins 4-6.

    Science.gov (United States)

    Bach, Leon A

    2015-10-01

    Insulin-like growth factor binding proteins (IGFBPs) 4-6 have important roles as modulators of IGF actions. IGFBP-4 and IGFBP-6 predominantly inhibit IGF actions, whereas IGFBP-5 may enhance these actions under some circumstances. IGFBP-6 is unique among the IGFBPs for its marked IGF-II binding preference. IGFBPs 4-6 are found in the circulation as binary complexes with IGFs that can enter tissues. Additionally, about half of the circulating IGFBP-5 is found in ternary complexes with IGFs and an acid labile subunit; this high molecular complex cannot leave the circulation and acts as an IGF reservoir. IGFBPs 4-6 also have IGF-independent actions. These IGFBPs are regulated in a cell-specific manner and their dysregulation may play a role in a range of diseases including cancer. However, there is no clear clinical indication for measuring serum levels of these IGFBPs at present. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Serum levels of insulin-like growth factor (IGF)-binding protein-3 (IGFBP-3) in healthy infants, children, and adolescents

    DEFF Research Database (Denmark)

    Juul, A; Dalgaard, P; Blum, W F

    1995-01-01

    -I. However, the diagnostic value of IGFBP-3 is still controversial, perhaps because the quality of the available normative data for IGFBP-3 varies. It has recently been shown that a large number of individuals is required to establish reference ranges for IGF-I that take into account age, sex, body mass...... in puberty. We found that IGFBP-3 levels increase with age in children, with maximal levels in puberty; girls experience peak values approximately 1 yr earlier than boys. Age, sex, height, BMI, and pubertal maturation were all important factors in determining the circulating levels of IGFBP-3, whereas IGF...... and conclude that age, sex, height, BMI, and pubertal maturation have to be taken into account before a single IGFBP-3 value in a growth-retarded child can be evaluated properly....

  20. Uterine receptivity and implantation: The regulation and action of insulin-like growth factor binding protein-1 (IGFBP-1, HOXA10 and forkhead transcription factor-1 (FOXO-1 in the baboon endometrium

    Directory of Open Access Journals (Sweden)

    Fazleabas Asgerally T

    2004-06-01

    Full Text Available Abstract In primates, the phase of the menstrual cycle when the uterus becomes receptive is initially dependent on estrogen and progesterone. Further morphological and biochemical changes are induced as a result of biochemical signals between the embryo and the maternal endometrium. Blastocyst implantation in the baboon usually occurs between 8 and 10 days post ovulation and is similar to that described for the rhesus macaque. In the baboon, when chorionic gonadotropin is infused in a manner that mimics blastocyst transit, this has physiological effects on the three major cell types in the uterine endometrium. The luminal epithelium undergoes endoreplication and distinct epithelial plaques are evident. The glandular epithelium responds by inducing transcriptional and post-translational modifications in the major secretory product, glycodelin. The stromal fibroblasts initiate their differentiation process into a decidual phenotype and are characterized by the expression of actin filaments. Decidualization, is the major change that occurs in the primate endometrium after conception. During this process the fibroblast-like stromal cells change morphologically into polygonal cells and express specific decidual proteins. Studies in the baboon demonstrated that insulin-like growth factor binding protein-1 (IGFBP-1 gene expression is a conceptus-mediated response. Subsequent studies in vitro established that IGFBP-1 is transcriptionally regulated by FOXO1 and HOXA10 which together upregulate the IGFBP-1 promoter activity. A baboon endometriosis model was utilized to determine if the changes observed during uterine receptivity in normally cycling animals were compromised. The data suggests that in animals with disease, markers of uterine receptivity are not appropriately expressed in the eutopic endometrium. It is possible that these differences influence the fertility of the animals with disease and the baboon could be used as a primate model to study

  1. The membrane-associated adaptor protein DOK5 is upregulated in systemic sclerosis and associated with IGFBP-5-induced fibrosis.

    Directory of Open Access Journals (Sweden)

    Hidekata Yasuoka

    Full Text Available Systemic sclerosis (SSc is characterized by excessive fibrosis of the skin and internal organs due to fibroblast proliferation and excessive production of extracellular matrix (ECM. We have shown that insulin-like growth factor binding protein (IGFBP-5 plays an important role in the development of fibrosis in vitro, ex vivo, and in vivo. We identified a membrane-associated adaptor protein, downstream of tyrosine kinase/docking protein (DOK5, as an IGFBP-5-regulated target gene using gene expression profiling of primary fibroblasts expressing IGFBP-5. DOK5 is a tyrosine kinase substrate associated with intracellular signaling. Our objective was to determine the role of DOK5 in the pathogenesis of SSc and specifically in IGFBP-5-induced fibrosis. DOK5 mRNA and protein levels were increased in vitro by endogenous and exogenous IGFBP-5 in primary human fibroblasts. DOK5 upregulation required activation of the mitogen-activated protein kinase (MAPK signaling cascade. Further, IGFBP-5 triggered nuclear translocation of DOK5. DOK5 protein levels were also increased in vivo in mouse skin and lung by IGFBP-5. To determine the effect of DOK5 on fibrosis, DOK5 was expressed ex vivo in human skin in organ culture. Expression of DOK5 in human skin resulted in a significant increase in dermal thickness. Lastly, levels of DOK5 were compared in primary fibroblasts and lung tissues of patients with SSc and healthy donors. Both DOK5 mRNA and protein levels were significantly increased in fibroblasts and skin tissues of patients with SSc compared with those of healthy controls, as well as in lung tissues of SSc patients. Our findings suggest that IGFBP-5 induces its pro-fibrotic effects, at least in part, via DOK5. Furthermore, IGFBP-5 and DOK5 are both increased in SSc fibroblasts and tissues and may thus be acting in concert to promote fibrosis.

  2. Insulin-like Growth Factor Binding Protein 7 Mediates Glioma Cell Growth and Migration

    Directory of Open Access Journals (Sweden)

    Wei Jiang

    2008-12-01

    Full Text Available Insulin-like growth factor binding protein 7 (IGFBP-7 is the only member of the IGFBP superfamily that binds strongly to insulin, suggesting that IGFBP-7 may have different functions from other IGFBPs. Unlike other IGFBPs, the expression and functions of IGFBP-7 in glioma tumors have not been reported. Using cDNA microarray analysis, we found that expression of IGFBP-7 correlated with the grade of glioma tumors and the overall patient survival. This finding was further validated by real-time reverse transcription-polymerase chain reaction and Western blot analysis. We used RNAi to examine the role of IGFBP-7 in glioma cells, inhibiting IGFBP-7 expression by short interfering RNA transfection. Cell proliferation was suppressed after IGFBP-7 expression was inhibited for 5 days, and glioma cell growth was stimulated consistently by the addition of recombinant IGFBP-7 protein. Moreover, glioma cell migration was attenuated by IGFBP-7 depletion but enhanced by IGFBP-7 overexpression and addition. Overexpression of AKT1 in IGFBP-7-overxpressed cells attenuated the IGFBP-7-promoted migration and further enhanced inhibition of IGFBP-7 depletion on the migration. Phosphorylation of AKT and Erk1/2 was also inversely regulated by IGFBP-7 expression. These two factors together suggest that IGFBP-7 can regulate glioma cell migration through the AKT-ERK pathway, thereby playing an important role in glioma growth and migration.

  3. HSP60, a protein downregulated by IGFBP7 in colorectal carcinoma

    Directory of Open Access Journals (Sweden)

    Lin Jie

    2010-04-01

    Full Text Available Abstract Background In our previous study, it was well defined that IGFBP7 was an important tumor suppressor gene in colorectal cancer (CRC. We aimed to uncover the downstream molecules responsible for IGFBP7's behaviour in this study. Methods Differentially expressed protein profiles between PcDNA3.1(IGFBP7-transfected RKO cells and the empty vector transfected controls were generated by two-dimensional gel electrophoresis (2-DE and mass spectrometry (MS identification. The selected differentially expressed protein induced by IGFBP7 was confirmed by western blot and ELISA. The biological behaviour of the protein was explored by cell growth assay and colony formation assay. Results Six unique proteins were found differentially expressed in PcDNA3.1(IGFBP7-transfected RKO cells, including albumin (ALB, 60 kDa heat shock protein(HSP60, Actin cytoplasmic 1 or 2, pyruvate kinase muscle 2(PKM2, beta subunit of phenylalanyl-tRNA synthetase(FARSB and hypothetical protein. The downregulation of HSP60 by IGFBP7 was confirmed by western blot and ELISA. Recombinant human HSP60 protein could increase the proliferation rate and the colony formation ability of PcDNA3.1(IGFBP7-RKO cells. Conclusion HSP60 was an important downstream molecule of IGFBP7. The downregulation of HSP60 induced by IGFBP7 may be, at least in part, responsible for IGFBP7's tumor suppressive biological behaviour in CRC.

  4. Insulin-like growth factor binding proteins increase intracellular calcium levels in two different cell lines.

    Directory of Open Access Journals (Sweden)

    Danielle Seurin

    Full Text Available BACKGROUND: Insulin-like growth factor binding proteins (IGFBPs are six related secreted proteins that share IGF-dependent and -independent functions. If the former functions begin to be well described, the latter are somewhat more difficult to investigate and to characterize. At the cellular level, IGFBPs were shown to modulate numerous processes including cell growth, differentiation and apoptosis. However, the molecular mechanisms implicated remain largely unknown. We previously demonstrated that IGFBP-3, but not IGFBP-1 or IGFBP-5, increase intracellular calcium concentration in MCF-7 cells (Ricort J-M et al. (2002 FEBS lett 527: 293-297. METHODOLOGY/PRINCIPAL FINDINGS: We perform a global analysis in which we studied, by two different approaches, the binding of each IGFBP isoform (i.e., IGFBP-1 to -6 to the surface of two different cellular models, MCF-7 breast adenocarcinoma cells and C2 myoblast proliferative cells, as well as the IGFBP-induced increase of intracellular calcium concentration. Using both confocal fluorescence microscopy and flow cytometry analysis, we showed that all IGFBPs bind to MCF-7 cell surface. By contrast, only four IGFBPs can bind to C2 cell surface since neither IGFBP-2 nor IGFBP-4 were detected. Among the six IGFBPs tested, only IGFBP-1 did not increased intracellular calcium concentration whatever the cellular model studied. By contrast, IGFBP-2, -3, -4 and -6, in MCF-7 cells, and IGFBP-3, -5 and -6, in C2 proliferative cells, induce a rapid and transient increase in intracellular free calcium concentration. Moreover, IGFBP-2 and -3 (in MCF-7 cells and IGFBP-5 (in C2 cells increase intracellular free calcium concentration by a pertussis toxin sensitive signaling pathway. CONCLUSIONS: Our results demonstrate that IGFBPs are able to bind to cell surface and increase intracellular calcium concentration. By characterizing the IGFBPs-induced cell responses and intracellular couplings, we highlight the cellular

  5. Relationship between insulin-like growth factor binding protein-3 and intelligence development of children with congenital hypothyroidism%IGFBP-3与先天性甲状腺功能减低症儿童智力发育的关系

    Institute of Scientific and Technical Information of China (English)

    蒋新液; 古桂雄; 裴晶晶; 于亮; 朱敏敏; 许飞; 陶晓红

    2011-01-01

    Objective: To explore the relationship between insulin - like growth factor binding protein - 3 ( IGFBP - 3 ) and intelligence development of children with congenital hypothyroidism (CH).Methods: Immunoradiometric assay was used to detect the expression level of IGFBP - 3, CDCC and C - WYCSI we re used to determine the levels of intelligence of children aged 2 ~ years old and 3 ~ 7 years old.Results: The intelligence quotients of the two groups were within normal range, but the intelligence quotient in case group was lower than that in control group (P < 0.05).Among the children aged 2 ~ years old, there was no significant difference in expression level of IGFBP - 3 between case group and control group ( P > 0.05 ); among the children aged 3 ~ 7 years old, the expression level of IGFBP - 3 in case group was lower than that in control group (P < 0.05 ).Among the children aged 2 ~ years old, there was no correlation between IGFBP - 3 and intelligence quotient (P > 0.05 ); among the children aged 3 ~ 7 years old, there was a positive correlation between IGFBP - 3 and linguistic IQ, Verbal intelligence quotient (P < 0.05).IGFBP - 3 level was selected as dependent variable, the scores of various tests in C - WYCSI were selected as independent variable, multivariate regression analysis was carried out, among intelligent factors, the first six effect factors of IGFBP -3 level were picture vocabulary, understanding, memory inverse order, maze, visual analysis and reciting orderly.Conclusion: For the children with CH, early diagnosis and timely treatment can avoid disorder of intelligence development, but injury of cognition exists; after early treatment, the serum level of IGFBP - 3 in the children with CH is still lower than that in normal children; the level of IGFBP - 3 is related to development of linguistic IQ in children; CH may induce low expression of IGFBP - 3 and affect the development of intelligence in children.%目的:探讨胰岛

  6. Recent Insights into Insulin-Like Growth Factor Binding Protein 2 Transcriptional Regulation

    OpenAIRE

    Shin, Minsang; Kang, Hye Suk; Park, Jae-Hyung; Bae, Jae-Hoon; Song, Dae-Kyu; Im, Seung-Soon

    2017-01-01

    Insulin-like growth factor binding proteins (IGFBPs) are major regulators of insulin-like growth factor bioavailability and activity in metabolic signaling. Seven IGFBP family isoforms have been identified. Recent studies have shown that IGFBPs play a pivotal role in metabolic signaling and disease, including the pathogenesis of obesity, diabetes, and cancer. Although many studies have documented the various roles played by IGFBPs, transcriptional regulation of IGFBPs is not well understood. ...

  7. Characterization of the insulin-like growth factor binding protein family in Xenopus tropicalis.

    Science.gov (United States)

    Haramoto, Yoshikazu; Oshima, Tomomi; Takahashi, Shuji; Ito, Yuzuru

    2014-01-01

    The insulin-like growth factor binding protein (Igfbp) family consists of six members designated Igfbp1-6. Igfbps are involved in many vital biological functions. They physically interact with IGFs (IGF1 and IGF2) and act as carriers, thereby protecting IGFs from proteolytic degradation. Thus, they function as modulators of IGF activity. Furthermore, Igfbps have been reported to have IGF-independent activities. They interact with other proteins, including cell surface proteins, extra-cellular matrix proteins, and potentially intracellular molecules. In Xenopus tropicalis (X. tropicalis), only four igfbp genes (igfbp1, igfbp2, igfbp4, and igfbp5) have been identified, and their expression is not well characterized. We report that X. tropicalis genome lacks the igfbp3 and igfbp6 genes based on synteny analyses. We also examined the spatio-temporal expression patterns of igfbp genes in early X. tropicalis development. Expression analyses indicated that they are differentially expressed during early development. Each igfbp gene showed a characteristic spatial expression pattern. Except for igfbp5, they demonstrated overlapping expression in the pronephros. The Xenopus pronephros is composed of four domains (i.e., the proximal tubule, intermediate tubule, distal tubule, and connecting tubule). Our results showed that at least two igfbp genes are co-expressed in all pronephric domains, suggesting that redundant functions of igfbp genes are required in early pronephric kidney development.

  8. Low serum levels of free and total insulin-like growth factor I (IGF-I) in patients with anorexia nervosa are not associated with increased IGF-binding protein-3 proteolysis

    DEFF Research Database (Denmark)

    Støving, R K; Flyvbjerg, A; Frystyk, J

    1999-01-01

    of GH-binding protein, free and total IGF-I, free IGF-II, and IGFBP-3 were significantly reduced; total IGF-II, IGFBP-2, and IGFBP-4 levels were unchanged; and IGFBP-1 was increased. No increased IGFBP-3 proteolytic activity could be detected in AN. In conclusion, the mechanisms responsible...

  9. Concentrations, release, and disposal of insulin-like growth factor (IGF)-binding proteins (IGFBP), IGF-I, and growth hormone in different vascular beds in patients with cirrhosis

    DEFF Research Database (Denmark)

    Møller, S; Juul, A; Becker, U

    1995-01-01

    in cirrhotics or controls. No significant differences were found in the values obtained simultaneously from hepatic, renal, and brachial veins or femoral artery, which suggests that no major net production or release of IGFBP-3 or IGF-I occurs in these tissues. No differences in IGFBP-2 or IGFBP-4 determined...

  10. OBSL1 mutations in 3-M syndrome are associated with a modulation of IGFBP2 and IGFBP5 expression levels

    DEFF Research Database (Denmark)

    Huber, Celine; Fradin, Mélanie; Edouard, Thomas

    2010-01-01

    decreased expression of IGFBP2 and increased expression of IGFBP5. However, direct sequencing of these two genes failed to detect any anomaly. We then considered other candidate genes by their function/location and found nine distinct mutations in the OBSL1 gene in 13 families including eight nonsense...... and one missense mutations. To further understand the links between OBSL1, CUL7, and insulin-like growth factor binding proteins (IGFBPs), we performed real-time quantitative PCR (RT-PCR) analysis for OBSL1, CUL7, IGFBP2, and IGFBP5, using cultured fibroblast RNAs from two patients with distinct OBSL1...... mutations (p.F697G; p.H814RfsX15). We found normal CUL7 mRNA levels but abnormal IGFBP2 and IGFBP5 mRNA levels in the two patients, suggesting that OBSL1 modulates the expression of IGFBP proteins....

  11. Insulin-like growth factor binding protein-6 delays replicative senescence of human fibroblasts

    DEFF Research Database (Denmark)

    Micutkova, Lucia; Diener, Thomas; Li, Chen;

    2011-01-01

    and apoptotic cell death was increased. Furthermore, downregulation of IGFBP-6 led to premature entry into cellular senescence. Since IGFBP-6 overexpression increased cellular lifespan, the data suggest that IGFBP-6, in contrast to other IGF binding proteins, is a negative regulator of cellular senescence...

  12. IGFBP2 potentiates nuclear EGFR-STAT3 signaling.

    Science.gov (United States)

    Chua, C Y; Liu, Y; Granberg, K J; Hu, L; Haapasalo, H; Annala, M J; Cogdell, D E; Verploegen, M; Moore, L M; Fuller, G N; Nykter, M; Cavenee, W K; Zhang, W

    2016-02-11

    Insulin-like growth factor binding protein 2 (IGFBP2) is a pleiotropic oncogenic protein that has both extracellular and intracellular functions. Despite a clear causal role in cancer development, the tumor-promoting mechanisms of IGFBP2 are poorly understood. The contributions of intracellular IGFBP2 to tumor development and progression are also unclear. Here we present evidence that both exogenous IGFBP2 treatment and cellular IGFBP2 overexpression lead to aberrant activation of epidermal growth factor receptor (EGFR), which subsequently activates signal transducer and activator of transcription factor 3 (STAT3) signaling. Furthermore, we demonstrate that IGFBP2 augments the nuclear accumulation of EGFR to potentiate STAT3 transactivation activities, via activation of the nuclear EGFR signaling pathway. Nuclear IGFBP2 directly influences the invasive and migratory capacities of human glioblastoma cells, providing a direct link between intracellular (and particularly nuclear) IGFBP2 and cancer hallmarks. These activities are also consistent with the strong association between IGFBP2 and STAT3-activated genes derived from The Cancer Genome Atlas database for human glioma. A high level of all three proteins (IGFBP2, EGFR and STAT3) was strongly correlated with poorer survival in an independent patient data set. These results identify a novel tumor-promoting function for IGFBP2 of activating EGFR/STAT3 signaling and facilitating EGFR accumulation in the nucleus, thereby deregulating EGFR signaling by two distinct mechanisms. As targeting EGFR in glioma has been relatively unsuccessful, this study suggests that IGFBP2 may be a novel therapeutic target.

  13. IGFBP2 potentiates nuclear EGFR-STAT3 signaling

    Science.gov (United States)

    Chua, Corrine Yingxuan; Liu, Yuexin; Granberg, Kirsi J.; Hu, Limei; Haapasalo, Hannu; Annala, Matti J.; Cogdell, David E.; Verploegen, Maartje; Moore, Lynette M.; Fuller, Gregory N.; Nykter, Matti; Cavenee, Webster K.; Zhang, Wei

    2015-01-01

    Insulin-like growth factor binding protein 2 (IGFBP2) is a pleiotropic oncogenic protein that has both extracellular and intracellular functions. Despite a clear causal role in cancer development, the tumor-promoting mechanisms of IGFBP2 are poorly understood. The contributions of intracellular IGFBP2 to tumor development and progression are also unclear. Here we present evidence that both exogenous IGFBP2 treatment and cellular IGFBP2 overexpression lead to aberrant activation of EGFR, which subsequently activates STAT3 signaling. Furthermore, we demonstrate that IGFBP2 augments the nuclear accumulation of EGFR to potentiate STAT3 transactivation activities, via activation of the nuclear EGFR signaling pathway. Nuclear IGFBP2 directly influences the invasive and migratory capacities of human glioblastoma cells, providing a direct link between intracellular (and particularly nuclear) IGFBP2 and cancer hallmarks. These activities are also consistent with the strong association between IGFBP2 and STAT3-activated genes derived from the TCGA database for human glioma. A high level of all 3 proteins (IGFBP2, EGFR and STAT3) was strongly correlated with poorer survival in an independent patient dataset. These results identify a novel tumor-promoting function for IGFBP2 of activating EGFR/STAT3 signaling and facilitating EGFR accumulation in the nucleus, thereby deregulating EGFR signaling by 2 distinct mechanisms. As targeting EGFR in glioma has been relatively unsuccessful, this study suggests that IGFBP2 may be a novel therapeutic target. PMID:25893308

  14. Expression of insulin-like growth factor binding protein-1 and -2 genes through the perinatal period in the rat.

    Science.gov (United States)

    Babajko, S; Hardouin, S; Segovia, B; Groyer, A; Binoux, M

    1993-06-01

    Insulin-like growth factor binding proteins (IGFBPs) are essential mediators of the bioavailability and biological effects of the IGFs. Liver expression of the rat (r) IGFBP-1 and rIGFBP-2 genes has been characterized between day 16 in utero (16 diu) and 16 days postnatally (+16 dpn). Run-on experiments showed transcriptional activity of the rIGFBP-1 and rIGFBP-2 genes at birth (B) to be 25 and 5 times that at 16 diu, respectively. After B, transcriptional activity of the rIGFBP-1 gene remained high (140% B at +6 dpn), but that of the rIGFBP-2 gene dropped to 70% B by +6 dpn. Northern blot analysis done simultaneously showed rIGFBP-1 messenger RNA (mRNA) levels to increase approximately 50-fold between 16 diu and B, whereas rIGFBP-2 mRNA increased only 5- to 10-fold. rIGFBP-1 mRNA levels decreased after birth, reaching about 20% B by +6 dpn; rIGFBP-2 mRNA, however, remained stable (about 80% B) at least up to +6 dpn. Parallel Western ligand blot and immunoblot analyses of serum rIGFBPs revealed rIGFBP-1 and rIGFBP-2 concentrations to be increased 3- and 2-fold, respectively between 20 diu and B. Maximal expression of rIGFBP-1 was at +1 dpn (220% B), and of rIGFBP-2, at B. Both rIGFBPs then decreased, reaching about 5% B at adulthood. All these data indicate that increased transcriptional activity of the rIGFBP-1 and rIGFBP-2 genes at birth would determine the increased synthesis in the liver and circulating levels of these proteins. In addition, it would seem that post-transcriptional events (reduced half-life of the rIGFBP-1 messenger after birth, translation efficiency of the rIGFBP-2 messenger) modulate transcriptional regulation.

  15. Quercetin induces p53-independent apoptosis in human prostate cancer cells by modulating Bcl-2-related proteins: a possible mediation by IGFBP-3.

    Science.gov (United States)

    Vijayababu, Marati R; Kanagaraj, P; Arunkumar, A; Ilangovan, R; Dharmarajan, A; Arunakaran, J

    2006-01-01

    Quercetin, a flavonoid found in onion, grapes, green vegetables, etc., has been shown to possess potent antiproliferative effects against various malignant cells. We report insulin-like growth factor-binding protein-3 (IGFBP-3) as an effector of quercetin-induced apoptosis in human prostate cancer cell lines in a p53-independent manner. We evaluated the production of IGFBP-3 in quercetin-treated cells. Apoptosis was studied in quercetin-treated cells to study the IGFBP-3-mediated role with flow cytometry and DNA fragmentation. Protein expressions of Bcl-2, Bcl-x(L), and Bax were studied by Western blot. Increased production of IGFBP-3 was associated with the increased ratio of proapoptotic to antiapoptotic members of the Bcl-2 family. In quercetin-treated PC-3 cells, an increase in Bax protein expression and a decrease in Bcl-x(L) protein and Bcl-2 protein were observed. As PC-3 is a p53-negative cell line, these modulations of proapoptotic proteins and induction of apoptosis were independent of p53. The level of IGFBP-3 on the response of PC-3 cells to quercetin was examined. There was a twofold increase in IGFBP-3 level in conditioned media of 100 microM quercetin-treated cells. Quercetin also brought a peak at sub-G1 in PC-3 cells. Thus, increased level of IGFBP-3 was associated with increased proapoptotic proteins and apoptosis in response to quercetin, suggesting it may be a p53-independent effector of apoptosis in prostate cancer cells via its modulation of the Bax/Bcl-2 protein ratio.

  16. Insulin-like growth factor binding protein 2 promotes ovarian cancer cell invasion

    Directory of Open Access Journals (Sweden)

    Liu Jinsong

    2005-02-01

    Full Text Available Abstract Background Insulin-like growth factor binding protein 2 (IGFBP2 is overexpressed in ovarian malignant tissues and in the serum and cystic fluid of ovarian cancer patients, suggesting an important role of IGFBP2 in the biology of ovarian cancer. The purpose of this study was to assess the role of increased IGFBP2 in ovarian cancer cells. Results Using western blotting and tissue microarray analyses, we showed that IGFBP2 was frequently overexpressed in ovarian carcinomas compared with normal ovarian tissues. Furthermore, IGFBP2 was significantly overexpressed in invasive serous ovarian carcinomas compared with borderline serous ovarian tumors. To test whether increased IGFBP2 contributes to the highly invasive nature of ovarian cancer cells, we generated IGFBP2-overexpressing cells from an SKOV3 ovarian cancer cell line, which has a very low level of endogenous IGFBP2. A Matrigel invasion assay showed that these IGFBP2-overexpressing cells were more invasive than the control cells. We then designed small interference RNA (siRNA molecules that attenuated IGFBP2 expression in PA-1 ovarian cancer cells, which have a high level of endogenous IGFBP2. The Matrigel invasion assay showed that the attenuation of IGFBP2 expression indeed decreased the invasiveness of PA-1 cells. Conclusions We therefore showed that IGFBP2 enhances the invasion capacity of ovarian cancer cells. Blockage of IGFBP2 may thus constitute a viable strategy for targeted cancer therapy.

  17. The ratio between serum levels of insulin-like growth factor (IGF)-I and the IGF binding proteins (IGFBP-1, 2 and 3) decreases with age in healthy adults and is increased in acromegalic patients

    DEFF Research Database (Denmark)

    Juul, A; Main, K; Blum, W F

    1994-01-01

    administration. Serum levels of IGF-I and IGFBP-3 decrease with age in normal adults and are elevated in active acromegaly due to excessive GH secretion. However, the individual ratios between serum levels of IGF-I and IGFBP-3 in acromegalic and healthy adults have not been described previously....

  18. The ratio between serum levels of insulin-like growth factor (IGF)-I and the IGF binding proteins (IGFBP-1, 2 and 3) decreases with age in healthy adults and is increased in acromegalic patients

    DEFF Research Database (Denmark)

    Juul, A; Main, K; Blum, W F;

    1994-01-01

    administration. Serum levels of IGF-I and IGFBP-3 decrease with age in normal adults and are elevated in active acromegaly due to excessive GH secretion. However, the individual ratios between serum levels of IGF-I and IGFBP-3 in acromegalic and healthy adults have not been described previously....

  19. Lamprey IGF-Binding Protein-3 Has IGF-Dependent and -Independent Actions

    Science.gov (United States)

    Zhong, Yingbin; Duan, Cunming

    2017-01-01

    Insulin-like growth factor-binding proteins (IGFBPs) are multifunctional proteins that possess IGF-dependent and -independent actions. Recent studies suggest that its IGF-independent action appeared early and that the IGF-binding function may have been acquired later in evolution. The timing of the emergence of IGF-dependent actions is unclear. Here, we identified and characterized an igfbp gene from sea lamprey, an agnathan, which was separated from the jawed vertebrates 450 million years ago. Phylogenetic and structural analyses suggested that the encoded protein belongs to the IGFBP-3 clade in the IGFBP family. Lamprey IGFBP-3 contains an IGF-binding domain (IBD), nuclear localization signal, and transactivation (TA) domain. Biochemical and functional analyses showed that these domains are all functional. Lamprey IGFBP-3 can bind IGFs and modulate IGF signaling when tested in mammalian cells. Lamprey IGFBP-3 also has the capacity to enter the nucleus and has strong TA activity. Forced expression of lamprey IGFBP-3, but not its IBD mutant, in zebrafish embryos decreased body growth and developmental speed. Lamprey IGFBP-3 inhibited BMP2 signaling in cultured cells and in zebrafish embryos, and this action is independent of its IGF-binding function. These results suggest that lamprey IGFBP-3 has both IGF-dependent and -independent actions and provide new insights into the functional evolution of the IGFBP family. PMID:28149290

  20. Insulinlike growth factor-binding protein proteolysis an emerging paradigm in insulinlike growth factor physiology.

    Science.gov (United States)

    Fowlkes, J L

    1997-10-01

    In biologic fluids, insulinlike growth factors (IGF-I and IGF-II) are bound to high-affinity insulinlike growth factor binding proteins (IGFBPs) of which seven have now been identified (IGFBPs 1-7). In a variety of biologic fluids, several IGFBPs undergo proteolytic degradation. Such degradation can lead to increased IGF bioavailability at the cell surface, facilitating receptor interactions. Herein, recent data identifying several IGFBP-degrading proteinases and their effects on IGF bioactivity is reviewed, and how IGFBP proteolysis is regulated by IGFs and IGFBPs, as well as how IGFBP cleavage analysis provides insights into the structure and function of IGFBPs, is explored. (Trends Endocrinol Metab 1997;8:299-306). (c) 1997, Elsevier Science Inc.

  1. IGFBP-5 Promotes Fibrosis Independently of Its Translocation to the Nucleus and Its Interaction with Nucleolin and IGF.

    Directory of Open Access Journals (Sweden)

    Yunyun Su

    Full Text Available Insulin-like growth factor binding protein (IGFBP-5 levels are increased in systemic sclerosis (SSc skin and lung. We previously reported that IGFBP-5 is a pro-fibrotic factor that induces extracellular matrix (ECM production and deposition. Since IGFBP-5 contains a nuclear localization signal (NLS that facilitates its nuclear translocation, we sought to examine the role of nuclear translocation on the fibrotic activity of IGFBP-5 and identify IGFBP-5 binding partners relevant for its nuclear compartmentalization.We generated functional wild type IGFBP-5 and IGFBP-5 with a mutated NLS or a mutated IGF binding site. Abrogation of nuclear translocation in the NLS mutant was confirmed using immunofluorescence and immunoblotting of nuclear and cytoplasmic cellular extracts. Abrogation of IGF binding was confirmed using western ligand blot. The fibrotic activity of wild type and mutant IGFBP-5 was examined in vitro in primary human fibroblasts and ex vivo in human skin. We identified IGFBP-5 binding partners using immunoprecipitation and mass spectrometry. We examined the effect of nucleolin on IGFBP-5 localization and function via sequence-specific silencing in primary human fibroblasts.Our results show that IGFBP-5-induced ECM production in vitro in primary human fibroblasts is independent of its nuclear translocation. The NLS-mutant also induced fibrosis ex vivo in human skin, thus confirming and extending the in vitro findings. Similar findings were obtained with the IGF-binding mutant. Nucleolin, a nucleolar protein that can serve as a nuclear receptor, was identified as an IGFBP-5 binding partner. Silencing nucleolin reduced IGFBP-5 translocation to the nucleus but did not block the ability of IGFBP-5 to induce ECM production and a fibrotic phenotype.IGFBP-5 transport to the nucleus requires an intact NLS and nucleolin. However, nuclear translocation is not necessary for IGFBP-5 fibrotic activity; neither is IGF binding. Our data provide

  2. Recent insights into the actions of IGFBP-6.

    Science.gov (United States)

    Bach, Leon A

    2015-06-01

    IGFBP-6 is an O-linked glycoprotein that preferentially binds IGF-II over IGF-I. It is a relatively selective inhibitor of IGF-II actions including proliferation, survival and differentiation of a wide range of cells. IGFBP-6 has recently been shown to have a number of IGF-independent actions, including promotion of apoptosis in some cells and inhibition of angiogenesis. IGFBP-6 also induces migration of tumour cells including rhabdomyosarcomas by an IGF-independent mechanism. This chemotactic effect is mediated by MAP kinases. IGFBP-6 binds to prohibitin-2 on the cell surface and the latter is required for IGFBP-6-induced migration by a mechanism that is independent of MAP kinases. IGFBP-6 may enter the nucleus and modulate cell survival and differentiation. IGFBP-6 expression is decreased in a number of cancer cells and it has been postulated to act as a tumour suppressor. IGFBP-6 expression is increased in a smaller number of cancers, which may reflect a compensatory mechanism to control IGF-II actions or IGF-independent actions. The relative balance of IGF-dependent and IGF-independent actions of IGFBP-6 in vivo together with the related question regarding the roles of IGFBP-6 binding to IGF and non-IGF ligands are keys to understanding the physiological role of this protein.

  3. Regulation of IGFBP secretion and modulation of cell growth in MDBK cells.

    Science.gov (United States)

    Cohick, W S; Clemmons, D R

    1993-03-01

    The ability of IGF binding proteins (IGFBP) to modulate cell growth and IGF-I responsiveness of epithelial cells was examined using the Madin-Darby bovine kidney (MDBK) cell line. The predominant IGFBP present in conditioned media (CM) of untreated cells was found to be IGFBP-2. Following exposure to forskolin, the abundance of IGFBP-2 in CM was decreased, while IGFBP-3 and -4 were induced. These changes corresponded with alterations in mRNA abundance. Growth of MDBK cells in serum-free media was stimulated by addition of 2.5 to 50 ng/ml of IGF-I in a dose responsive manner. Coincubation with equimolar amounts of IGF-I and exogenous bovine IGFBP-3 potentiated the growth response observed with IGF-I alone. In order to alter endogenous IGFBP-3 secretion, cells were exposed to transfection with an expression vector containing sense IGFBP-3 cDNA. Following selection and amplification with methotrexate, cells underwent a permanent alteration in cell morphology, exhibiting characteristics of transporting epithelia. This was associated with secretion of IGFBP-3 under basal conditions. Secretion of IGFBP-3 was due to expression of endogenous IGFBP-3 and not to expression of the transgene. Cells expressing IGFBP-3 under basal conditions grew slower in serum, but were more responsive to 100 ng/ml of IGF-1 in serum-free media compared to wild-type MDBK cells. The role of IGFBP-3 in mediating these responses requires further study.

  4. ADAM 12-S cleaves IGFBP-3 and IGFBP-5 and is inhibited by TIMP-3

    DEFF Research Database (Denmark)

    Loechel, F; Fox, J W; Murphy, G;

    2000-01-01

    that it cleaves insulin-like growth factor binding protein-3 (IGFBP-3). This result supports a role for ADAM 12-S in the degradation of IGFBP-3 in the blood of pregnant women. Furthermore, we tested for proteolysis of other members of the IGF binding protein family and found that ADAM 12-S cleaves IGFBP-5......ADAMs are a family of multidomain proteins having proteolytic and cell adhesion activities. We have previously shown that ADAM 12-S, the secreted soluble form of human ADAM 12, is a catalytically active protease. We now describe the purification of full-length recombinant ADAM 12-S and demonstrate...... in addition to IGFBP-3, but does not cleave IGFBP-1, -2, -4, or -6. ADAM 12-S may therefore be the IGFBP-5 protease that is secreted by osteoblasts and other cells. Cleavage of both IGFBP-3 and -5 by ADAM 12-S was inhibited by TIMP-3, raising the possibility that TIMP-3 is a physiological inhibitor of ADAM 12...

  5. Duplication and diversification of the hypoxia-inducible IGFBP-1 gene in zebrafish.

    Directory of Open Access Journals (Sweden)

    Hiroyasu Kamei

    Full Text Available BACKGROUND: Gene duplication is the primary force of new gene evolution. Deciphering whether a pair of duplicated genes has evolved divergent functions is often challenging. The zebrafish is uniquely positioned to provide insight into the process of functional gene evolution due to its amenability to genetic and experimental manipulation and because it possess a large number of duplicated genes. METHODOLOGY/PRINCIPAL FINDINGS: We report the identification and characterization of two hypoxia-inducible genes in zebrafish that are co-ortholgs of human IGF binding protein-1 (IGFBP-1. IGFBP-1 is a secreted protein that binds to IGF and modulates IGF actions in somatic growth, development, and aging. Like their human and mouse counterparts, in adult zebrafish igfbp-1a and igfbp-1b are exclusively expressed in the liver. During embryogenesis, the two genes are expressed in overlapping spatial domains but with distinct temporal patterns. While zebrafish IGFBP-1a mRNA was easily detected throughout embryogenesis, IGFBP-1b mRNA was detectable only in advanced stages. Hypoxia induces igfbp-1a expression in early embryogenesis, but induces the igfbp-1b expression later in embryogenesis. Both IGFBP-1a and -b are capable of IGF binding, but IGFBP-1b has much lower affinities for IGF-I and -II because of greater dissociation rates. Overexpression of IGFBP-1a and -1b in zebrafish embryos caused significant decreases in growth and developmental rates. When tested in cultured zebrafish embryonic cells, IGFBP-1a and -1b both inhibited IGF-1-induced cell proliferation but the activity of IGFBP-1b was significantly weaker. CONCLUSIONS/SIGNIFICANCE: These results indicate subfunction partitioning of the duplicated IGFBP-1 genes at the levels of gene expression, physiological regulation, protein structure, and biological actions. The duplicated IGFBP-1 may provide additional flexibility in fine-tuning IGF signaling activities under hypoxia and other catabolic

  6. Glioma progression is mediated by an addiction to aberrant IGFBP2 expression and can be blocked using anti-IGFBP2 strategies.

    Science.gov (United States)

    Phillips, Lynette M; Zhou, Xinhui; Cogdell, David E; Chua, Corrine Yingxuan; Huisinga, Anouk; R Hess, Kenneth; Fuller, Gregory N; Zhang, Wei

    2016-07-01

    Insulin-like growth factor binding protein 2 (IGFBP2) overexpression is common in high-grade glioma and is both a strong biomarker of aggressive behaviour and a well-documented prognostic factor. IGFBP2 is a member of the secreted IGFBP family that functions by interacting with circulating IGFs to modulate IGF-mediated signalling. This traditional view of IGFBP2 activities has been challenged by the recognition of the diverse functions and cellular locations of members of the IGFBP family. IGFBP2 has been previously established as a driver of glioma progression to a higher grade. In this study, we sought to determine whether IGFBP2-overexpressing tumours are dependent on continued oncogene expression and whether IGFBP2 is a viable therapeutic target in glioma. We took advantage of the well-characterized RCAS/Ntv-a mouse model to create a doxycycline-inducible IGFBP2 model of glioma and demonstrated that the temporal expression of IGFBP2 has dramatic impacts on tumour progression and survival. Further, we demonstrated that IGFBP2-driven tumours are dependent on the continued expression of IGFBP2, as withdrawal of this oncogenic signal led to a significant decrease in tumour progression and prolonged survival. Inhibition of IGFBP2 also impaired tumour cell spread. To assess a therapeutically relevant inhibition strategy, we evaluated a neutralizing antibody against IGFBP2 and demonstrated that it impaired downstream IGFBP2-mediated oncogenic signalling pathways. The studies presented here indicate that IGFBP2 not only is a driver of glioma progression and a prognostic factor but is also required for tumour maintenance and thus represents a viable therapeutic target in the treatment of glioma. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

  7. Insulin-like growth factor binding protein 3 in inflammatory bowel disease

    DEFF Research Database (Denmark)

    Kirman, Irena; Whelan, Richard Larry; Jain, Suvinit;

    2005-01-01

    Epithelial cell growth regulation has been reported to be altered in inflammatory bowel disease (IBD) patients. The cell growth regulatory factor, insulin-like growth factor binding protein 3 (IGFBP-3), may be partly responsible for this phenomenon. So far, IGFBP-3 levels have been assessed...... as values of total protein, which is a sum of bioactive intact 43- to 45-kDa protein and its inactive proteolytic cleavage fragments. We aimed to assess the levels of intact IGFBP-3 and its cleaving protease MMP-9 in IBD. Patients with IBD and controls were included. Total plasma IGFBP-3 concentration...... and MMP-9 levels were determined in ELISA. The concentration of intact IGFBP-3 was significantly decreased in patients with moderate to severe IBD activity compared to those in remission or controls. Of note, a dramatic depletion of intact IGFBP-3 was found in 7.4% of patients with IBD. Zymography...

  8. Role of insulin-like growth factor binding protein-4 in prevention of colon cancer

    Directory of Open Access Journals (Sweden)

    Seifalian Alexander M

    2007-11-01

    Full Text Available Abstract Background Insulin-like growth factors (IGFs are important for the proliferation of cancer cells. One of their binding proteins, known as insulin-like growth factor binding protein -4 (IGFBP-4 is well known for its inhibitory action on IGFs in vitro. We assessed the effect of IGFBP-4 in prevention of development of colon cancer in vivo. Methods Nude mice were subcutaneously inoculated with HT-29 colon cancer cells and they were also simultaneously injected either gene construct containing mammalian expression vector pcDNA3 with or without IGFBP-4 gene or phosphate buffered saline. The effect was assessed 4 weeks later by evaluating the tumours for mitosis, necrosis, apoptosis, and expressions of IGFBP-4, Bcl-2 and Bax proteins. Results The results showed that the IGFBP-4 gene therapy did not prevent the tumour establishment but it increased the tumour apoptosis which was associated with an increase in Bcl-2 and Bax expressions. The IGFBP-4 protein was low in tumours which received IGFBP-4 gene construct which may be due to a feed back mechanism of IGFBP-4 upon its own cells. Conclusion IGFBP-4 gene therapy in the form localised gene transfer did not prevent colon cancer initiation and establishment but it resulted in increased apoptosis and Bax protein expression and a decrease in tumour cellular mitosis

  9. Insulin-like growth factor binding protein-I-6 expression in activated microglia

    NARCIS (Netherlands)

    Chesik, D.; Glazenburg, K.; Wilczak, N.; Geeraedts, Felix; De Keyser, J.

    2004-01-01

    In the CNS insulin-like growth factor-1 (IGF-1) enhances survival of neurons, promotes myelin synthesis and acts as a mitogen for microglia. The effects of IGF-1 are regulated by a family of 6 IGF binding proteins (IGFBPs). We investigated mRNA expression patterns of IGFBPs in primary rat microglia

  10. 子宫内膜腺癌组织中 IGFBP-rP1基因的甲基化状态及其 mR-NA、蛋白表达水平的检测%Detection of methylation of IGFBP-rP1 gene and relationship with its mR-NA and protein expressions in endometrial adenocarcinoma tissue

    Institute of Scientific and Technical Information of China (English)

    郭瑞霞; 范丽君; 李艳敏

    2015-01-01

    目的:探讨子宫内膜腺癌组织中胰岛素样生长因子结合蛋白相关蛋白1( IGFBP-rP1)基因的甲基化状态及其与IGFBP-rP1 mRNA、蛋白表达之间的关系。方法:采用甲基化特异性PCR检测45例子宫内膜腺癌、30例子宫内膜单纯性增生和30例子宫内膜不典型增生组织中IGFBP-rP1基因启动子区和第一外显子区CpG岛的甲基化状态;采用实时荧光定量PCR和免疫组化SP法分别检测上述3种组织中IGFBP-rP1 mRNA和蛋白的表达。结果:子宫内膜腺癌组织中IGFBP-rP1基因在启动子区的甲基化率高于其在第一外显子区的甲基化率(χ2=6.429,P=0.011)。子宫内膜腺癌组织中IGFBP-rP1基因在启动子区的甲基化率低于子宫内膜不典型增生组织和单纯性增生组织(F=14.659,P=0.001)。子宫内膜腺癌组织中IGFBP-rP1 mRNA和蛋白的表达均高于子宫内膜不典型增生组织和单纯性增生组织(F=8.619、χ2=23.611,P均<0.05);在启动子区发生IGFBP-rP1基因甲基化的子宫内膜腺癌组织中,其mRNA的表达水平低于未甲基化组(t=4.758,P=0.001),其蛋白的表达与甲基化状态呈负关联(rP =-0.625,P<0.001)。结论:子宫内膜腺癌组织中IGFBP-rP1基因甲基化主要发生在启动子区,且呈低甲基化状态;IGFBP-rP1启动子区的低甲基化状态可能是IGFBP-rP1基因在子宫内膜腺癌组织中高表达的调控机制之一。%Aim:To investigate the methylation of insulin like growth factor binding protein-related protein 1( IGFBP-rP1 ) gene and its relationship with the expressions of IGFBP-rP1 mRNA and protein in endometrial adenocarcinoma tissue . Methods:Methylation-specific PCR was used to detect the methylation status of IGFBP-rP1 gene in the promoter region and the first exon region in 45 cases of endometrial adenocarcinoma ,30 cases of endometrial atypical hyperplasia , and 30 cases of

  11. Mutation of the RGD sequence does not affect plasma membrane association and growth inhibitory effects of elevated IGFBP-2 in vivo

    NARCIS (Netherlands)

    Hoeflich, A; Reisinger, R; Vargas, GA; Elmlinger, MW; Schuett, B; Jehle, PM; Renner-Muller, [No Value; Lahm, H; Russo, VC; Wolf, E

    2002-01-01

    Using insulin-like growth factor-binding protein-2 (IGFBP-2) transgenic mice (D mice) as a model of elevated IGFBP-2 expression, which is often found in unphysiological conditions, we found association of IGFBP-2 to purified plasma membranes of many organs. To determine whether the RGD (Arg-Gly-Asp)

  12. Targeted expression of a protease-resistant IGFBP-4 mutant in smooth muscle of transgenic mice results in IGFBP-4 stabilization and smooth muscle hypotrophy.

    Science.gov (United States)

    Zhang, Mingyu; Smith, Eric P; Kuroda, Hiroaki; Banach, Walter; Chernausek, Steven D; Fagin, James A

    2002-06-14

    The insulin-like growth factor-binding protein 4 (IGFBP-4), the most abundant IGF-binding protein produced by rodent smooth muscle cells (SMC), is degraded by specific protease(s) potentially releasing IGF-I for local bioactivity. IGFBP-4 protease(s) recognizes basic residues within the midregion of the molecule. We constructed a mutant IGFBP-4 with the cleavage domain substitution 119-KHMAKVRDRSKMK-133 to 119-AAMAAVADASAMA-133. Myc-tagged native and IGFBP-4.7A retained equivalent IGF-I binding affinity. Whereas native IGFBP-4 was cleaved by SMC-conditioned medium, IGFBP-4.7A was completely resistant to proteolysis. To explore the function of the protease-resistant IGFBP-4 in vivo, expression of the mutant and native proteins was targeted to SMC of transgenic mice by means of a smooth muscle alpha-actin promoter. Transgene expression was confined to SMC-rich tissues in all lines. Bladder and aortic immunoreactive IGFBP-4/transgene mRNA ratios in SMP8-BP4.7A mice were increased by 2- to 4-fold relative to SMP8-BP4 mice, indicating that the IGFBP-4.7A protein was stabilized in vivo. SMP8-BP4.7A mice had lower aortic, bladder, and stomach weight and intestinal length relative to SMP8-BP4 counterparts matched for protein expression by Western blotting. Thus, IGFBP-4.7A results in greater growth inhibition than equivalent levels of native IGFBP-4 in vivo, demonstrating a role for IGFBP-4 proteolysis in the regulation of IGF-I action.

  13. Abnormal IGF-Binding Protein Profile in the Bone Marrow of Multiple Myeloma Patients.

    Directory of Open Access Journals (Sweden)

    Liesbeth Bieghs

    Full Text Available Insulin-like growth factor (IGF signalling plays a key role in homing, progression, and treatment resistance in multiple myeloma (MM. In the extracellular environment, the majority of IGF molecules are bound to one of six IGF-binding proteins (IGFBP1-6, leaving a minor fraction of total IGF free and accessible for receptor activation. In MM, high IGF-receptor type 1 expression levels correlate with a poor prognosis, but the status and role of IGF and IGFBPs in the pathobiology of MM is unknown. Here we measured total IGF1, IGF2, and intact IGFBP levels in blood and bone marrow samples from MM (n = 17, monoclonal gammopathy of undetermined significance (MGUS (n = 37, and control individuals (n = 15, using ELISA (IGFs and 125I-IGF1 Western Ligand Blotting (IGFBPs. MGUS and MM patients displayed a significant increase in intact IGFBP-2 (2.5-3.8 fold and decrease in intact IGFBP-3 (0.6-0.5 fold in the circulation compared to control individuals. Further, IGFBP-2 as well as total IGFBP levels were significantly lower in bone marrow compared to circulation in MM and MGUS only, whereas IGF1, IGF2, and IGFBP-3 were equally distributed between the two compartments. In conclusion, the profound change in IGFBP profile strongly suggests an increased IGF bioavailability in the bone marrow microenvironment in MGUS and MM, despite no change in growth factor concentration.

  14. Amblyomma americanum tick saliva insulin-like growth factor binding protein-related protein 1 binds insulin but not insulin-like growth factors.

    Science.gov (United States)

    Radulović, Ž M; Porter, L M; Kim, T K; Bakshi, M; Mulenga, A

    2015-10-01

    Silencing Amblyomma americanum insulin-like growth factor binding protein-related protein 1 (AamIGFBP-rP1) mRNA prevented ticks from feeding to repletion. In this study, we used recombinant (r)AamIGFBP-rP1 in a series of assays to obtain further insight into the role(s) of this protein in tick feeding regulation. Our results suggest that AamIGFBP-1 is an antigenic protein that is apparently exclusively expressed in salivary glands. We found that both males and females secrete AamIGFBP-rP1 into the host during feeding and confirmed that female ticks secrete this protein from within 24-48 h after attachment. Our data suggest that native AamIGFBP-rP1 is a functional insulin binding protein in that both yeast- and insect cell-expressed rAamIGFBP-rP1 bound insulin, but not insulin-like growth factors. When subjected to anti-blood clotting and platelet aggregation assays, rAamIGFBP-rP1 did not have any effect. Unlike human IGFBP-rP1, which is controlled by trypsinization, rAamIGFBP-rP1 is resistant to digestion, suggesting that the tick protein may not be under mammalian host control at the tick feeding site. The majority of tick-borne pathogens are transmitted 48 h after the tick has attached. Thus, the demonstrated antigenicity and secretion into the host within 24-48 h of the tick starting to feed makes AamIGFBP-rP1 an attractive target for antitick vaccine development.

  15. Low serum levels of free and total insulin-like growth factor I (IGF-I) in patients with anorexia nervosa are not associated with increased IGF-binding protein-3 proteolysis.

    Science.gov (United States)

    Støving, R K; Flyvbjerg, A; Frystyk, J; Fisker, S; Hangaard, J; Hansen-Nord, M; Hagen, C

    1999-04-01

    Patients with anorexia nervosa (AN) are GH resistant, with elevated GH levels and low serum levels of total insulin-like growth factor I (IGF-I). IGF-I action is modulated by IGF-binding proteins (IGFBPs), and a variety of catabolic states has been characterized by the presence of increased IGFBP-3 proteolysis. The present study was performed to examine the levels of free IGFs in AN and to clarify whether AN is associated with increased IGFBP-3 proteolytic activity. In 24 patients and 10 age-matched controls, the fasting serum concentrations of free IGF-I and -II were measured using ultrafiltration by centrifugation. In addition, GH, GH-binding protein, total IGFs, IGFBP-1 to -4, and IGFBP-3 proteolytic activity were measured. The IGFBPs were measured by both immunoassays and Western ligand blotting. Twelve of the patients were restudied 3 months after a minor increase in body mass index. In AN, the levels of GH-binding protein, free and total IGF-I, free IGF-II, and IGFBP-3 were significantly reduced; total IGF-II, IGFBP-2, and IGFBP-4 levels were unchanged; and IGFBP-1 was increased. No increased IGFBP-3 proteolytic activity could be detected in AN. In conclusion, the mechanisms responsible for the adaption of the GH-IGF-IGFBP axis in AN may be different from other catabolic conditions, because the low levels of free and total IGF-I in AN are not associated with increased IGFBP-3 proteolysis.

  16. Local IGFBP-3 mRNA expression, apoptosis and risk of colorectal adenomas

    Directory of Open Access Journals (Sweden)

    Omofoye Oluwaseun

    2008-05-01

    Full Text Available Abstract Background IGF binding protein-3 (IGFBP-3 regulates the bioavailability of insulin-like growth factors I and II, and has both anti-proliferative and pro-apoptotic properties. Elevated plasma IGFBP-3 has been associated with reduced risk of colorectal cancer (CRC, but the role of tissue IGFBP-3 is not well defined. We evaluated the association between tissue or plasma IGFBP-3 and risk of colorectal adenomas or low apoptosis. Methods Subjects were consenting patients who underwent a clinically indicated colonoscopy at UNC Hospitals and provided information on diet and lifestyle. IGFBP-3 mRNA in normal colon was assessed by real time RT-PCR. Plasma IGFBP-3 was measured by ELISA and apoptosis was determined by morphology on H & E slides. Logistic regression was used to compute odds ratio (OR and 95% confidence intervals. Results We observed a modest correlation between plasma IGFBP-3 and tissue IGFBP-3 expression (p = 0.007. There was no significant association between plasma IGFBP-3 and adenomas or apoptosis. Tissue IGFBP-3 mRNA expression was significantly lower in cases than controls. Subjects in the lowest three quartiles of tissue IGFBP-3 gene expression were more likely to have adenomas. Consistent with previous reports, low apoptosis was significantly associated with increased risk of adenomas (p = 0.003. Surprisingly, local IGFBP-3 mRNA expression was inversely associated with apoptosis. Conclusion Low expression of IGFBP-3 mRNA in normal colonic mucosa predicts increased risk of adenomas. Our findings suggest that local IGFBP-3 in the colon may directly increase adenoma risk but IGFBP-3 may act through a pathway other than apoptosis to influence adenoma risk.

  17. Insulin-like growth factor binding protein-5 modulates muscle differentiation through an insulin-like growth factor-dependent mechanism.

    Science.gov (United States)

    James, P L; Stewart, C E; Rotwein, P

    1996-05-01

    The insulin-like growth factor binding proteins (IGFBPs) are a family of six secreted proteins which bind to and modulate the actions of insulin-like growth factors-I and -II (IGF-I and -II). IGFBP-5 is more conserved than other IGFBPs characterized to date, and is expressed in adult rodent muscle and in the developing myotome. We have shown previously that C2 myoblasts secrete IGFBP-5 as their sole IGFBP. Here we use these cells to study the function of IGFBP-5 during myogenesis, a process stimulated by IGFs. We stably transfected C2 cells with IGFBP-5 cDNAs under control of a constitutively active promoter. Compared with vector-transfected control cells, C2 myoblasts expressing the IGFBP-5 transgene in the sense orientation exhibit increased IGFBP-5 levels in the extracellular matrix during proliferation, and subsequently fail to differentiate normally, as assessed by both morphological and biochemical criteria. Compared to controls, IGFBP-5 sense myoblasts show enhanced survival in low serum medium, remaining viable for at least four weeks in culture. By contrast, myoblasts expressing the IGFBP-5 antisense transcript differentiate prematurely and more extensively than control cells. The inhibition of myogenic differentiation by high level expression of IGFBP-5 could be overcome by exogenous IGFs, with des (1-3) IGF-I, an analogue with decreased affinity for IGFBP-5 but normal affinity for the IGF-I receptor, showing the highest potency. These results are consistent with a model in which IGFBP-5 blocks IGF-stimulated myogenesis, and indicate that sequestration of IGFs in the extracellular matrix could be a possible mechanism of action. Our observations also suggest that IGFBP-5 normally inhibits muscle differentiation, and imply a role for IGFBP-5 in regulating IGF action during myogenic development in vivo.

  18. Mandibular repositioning modulates IGFBP-3, -4, -5 and -6 expression in the mandibular condylar cartilage of young rats.

    Science.gov (United States)

    Hajjar, Denise; Santos, Marinilce F; Kimura, Edna Teruko

    2006-01-01

    Functional orthopedic appliances correct dental malocclusion partially by exerting indirect mechanical stimulus on the condylar cartilage, modulating growth and the adaptation of orofacial structures. However, the exact nature of the biological responses to this therapy is not well understood. Insulin-like growth factors I and II (IGF-I and II) are important local factors during growth and differentiation in the condylar cartilage [D. Hajjar, M.F. Santos and E.T. Kimura, Propulsive appliance stimulates the synthesis of insulin-like growth factors I and II in the mandibular condylar cartilage of young rats, Arch. Oral Biol. 48 (2003), 635-642]. The bioefficacy of IGFs at the cellular level is modulated by IGF binding proteins (IGFBP). The aim of this study was to verify the mRNA and protein expression of IGFBP-3, IGFBP-4, IGFBP-5 and IGFBP-6 in the condylar cartilage of young male Wistar rats that used a mandibular propulsive appliance for 3, 9, 15, 20, 30 or 35 days. For this purpose, sagittal sections of decalcified and paraffin-embedded condyles were submitted to immunohistochemistry and the condylar cartilage to RT-PCR. The control group showed a gradual increase in the protein expression of all IGFBPs, except IGFBP-4. Following use of the appliance, IGFBP-3 and IGFBP-6 expression decreased in the early stage of the treatment. At 20 days of treatment there was a decline in the IGFs and IGFBP-3, IGFBP-4 and IGFBP-5 expression and at 30 days there was a peak in the IGFs and all IGFBPs expression except for IGFBP-3 where the peak was observed in the control animals. The expression patterns of all IGFBPs in the condylar cartilage were similar. The modulation of IGFBP-3, -4, -5 and -6 expression in the condylar cartilage in response to the propulsive appliance suggests that those peptides are involved in the mandibular adaptation during this therapy.

  19. Changes in circulating level of IGF-I and IGF-binding protein-1 from the first to second trimester as predictors of preeclampsia

    DEFF Research Database (Denmark)

    Vatten, Lars J; Nilsen, Tom I L; Juul, Anders;

    2008-01-01

    To assess whether circulating IGF-I and IGF-binding protein-1 (IGFBP-1) in the first and second trimester are associated with subsequent risk of preterm and term preeclampsia.......To assess whether circulating IGF-I and IGF-binding protein-1 (IGFBP-1) in the first and second trimester are associated with subsequent risk of preterm and term preeclampsia....

  20. Synthesis of insulin-like growth factor binding protein 3 in vitro in human articular cartilage cultures.

    Science.gov (United States)

    Eviatar, Tamar; Kauffman, Hannah; Maroudas, Alice

    2003-02-01

    To quantify the rate of synthesis of insulin-like growth factor binding protein 3 (IGFBP-3) and insulin-like growth factor 1 (IGF-1) by in vitro cultures of normal and osteoarthritic (OA) human articular cartilage. Levels of IGF-1 and IGFBP-3 in media from in vitro cultures of human cartilage were determined by radioimmunoassay (RIA). IGFBPs were characterized by immunoblots and ligand blots. Ultrafiltration and RIA analysis of synovial fluid (SF) samples and washings of cartilage samples ex vivo were used to calculate partition coefficients and to estimate the amount of IGF-1 and IGFBP-3 in cartilage in vivo. OA cartilage synthesized 150 ng of IGFBP-3 per gm of cartilage per day, compared with 50 ng synthesized by normal cartilage. The surface zone of normal cartilage produced more IGFBP-3 than did the deep zone. Immunoblots and ligand blots confirmed the presence of IGFBP-3. IGFBP-3 synthesis was stimulated by exogenous IGF-1. No freshly synthesized IGF-1 was detected. The quantities of IGF-1 and IGFBP-3 present ex vivo were 11.3 and 78.7 ng/gm of cartilage in normal cartilage and 21.6 and 225.4 ng/gm in OA cartilage. The results show that while IGFBP-3 is synthesized in explant cultures, IGF-1 is not. The rate of IGFBP-3 synthesis is 3 times higher in OA than in normal cartilage. Both IGFBP-3 and IGF-1 penetrate into cartilage from SF in vivo. We estimate that the quantities of IGFBP-3 produced in culture by human cartilage are small compared with the amount supplied in the form of "small complexes" from the circulation. The high value of the partition coefficient of IGFBP-3 implies binding to the matrix.

  1. Two grass carp (Ctenopharyngodon idella) insulin-like growth factor-binding protein 5 genes exhibit different yet conserved functions in development and growth.

    Science.gov (United States)

    Zheng, Guo-Dong; Zhou, Chun-Xue; Lin, Si-Tong; Chen, Jie; Jiang, Xia-Yun; Zou, Shu-Ming

    2017-02-01

    Insulin-like growth factor binding-protein 5 (igfbp5), the most conserved member of the IGFBP family in vertebrates, plays a critical role in controlling cell survival, growth, differentiation, and apoptosis. Here, we characterized the expression patterns of igfbp5a and igfbp5b in grass carp (Ctenopharyngodon idella), which are retained in many fish species, likely from the teleost-specific whole-genome duplication. Both igfbp5a and igfbp5b encode 268- and 263-aa peptides, respectively, which share a sequence identity of 71%. Their mRNAs are not detected in zygotes. At 14hpf, grass carp igfbp5b mRNA was detected in the somites, while igfbp5a mRNA has some possible signal around the eye and head region. At 24hpf, both igfbp5a and igfbp5b mRNA appear to be limited to the presomitic mesoderm. At 36hpf, igfbp5a mRNA was only detected in the midbrain, while igfbp5b mRNA was detected in both the midbrain and notochord. Overall, both mRNAs were expressed in most adult tissues. igfbp5a and igfbp5b were significantly upregulated in the muscle and liver after injection of 10μg per kilogram body weight of zebrafish growth hormone (zGH), while their hepatic expression was downregulated by 50μg zGH. During fasting, both igfbp5a and igfbp5b mRNAs were significantly downregulated in the muscle but upregulated in the liver. Collectively, the results suggest that the two igfbp5 genes play important but different roles in the regulation of growth and development in grass carp.

  2. Insulin-like growth factor binding protein-2, 28 kDa an 24 kDa insulin-like growth factor binding protein levels are decreased in fluid of dominant follicles, obtained from normal and polycystic ovaries

    NARCIS (Netherlands)

    A.G.P. Schuller (Alwin); D.J. Lindenbergh-Kortleve (Dicky); T.D. Pache; E.C. Zwarthoff (Ellen); B.C.J.M. Fauser (Bart); S.L.S. Drop (Stenvert)

    1993-01-01

    textabstractIn order to investigate potential changes in insulin-like growth factor binding proteins (IGFBPs) during human follicle maturation, we examined the IGFBP profiles in follicular fluid from follicles in different stages of maturation. Samples were obtained from ovaries of women with

  3. IGF-I and IGFBP2 in peripheral artery disease

    DEFF Research Database (Denmark)

    Urbonaviciene, Grazina; Frystyk, Jan; Urbonavicius, Sigitas

    2014-01-01

    -2) in the pathogenesis of CVD disorders. The aim of this study was to examine the relationship between levels of IGF-I and IGFBP-2 with all-cause and CVD mortality in a prospective study of patients with lower-extremity peripheral artery disease (PAD). METHODS AND MATERIAL: Serum IGF-I and IGFBP-2......BACKGROUND AND OBJECTIVES: The search for novel risk factors of cardiovascular disease (CVD) has provided valuable clinical data concerning underlying mechanism of disease. Increasing evidence indicates a possible involvement of insulin-like growth factor-I (IGF-I) and its binding protein 2 (IGFBP...

  4. IGF-binding proteins in type 1 diabetes are more severely altered in the presence of complications

    Directory of Open Access Journals (Sweden)

    Ashok eSharma

    2016-01-01

    Full Text Available Aims: Reduced levels of free and total insulin-like growth factor 1 (IGF-I have been observed in Type-1 Diabetes (T1D patients. The bioavailability of IGF-I from the circulation to the target cells is controlled by multifunctional IGF binding proteins (IGFBPs. The aim of this study was to profile serum IGFBPs in T1D and its complications.Design: We measured the IGFBP levels in 3662 patient serum samples from our ongoing Phenome and Genome of Diabetes Autoimmunity (PAGODA study. IGFBP levels of four different groups of T1D patients (with 0, 1, 2, ≥3 complications were compared with healthy controls. Results: Three serum IGFBPs (IGFBP-1, 2 and 6 are significantly higher in T1D patients and these alterations are greater in the presence of diabetic complications. IGFBP-3 is lower in patients with diabetic complications. Analyses using quintiles revealed that risk of T1D complications increases with increasing concentrations of IGFBP-2 (5th quintile ORs: 18-60, p<10-26, IGFBP-1 (5th quintile ORs: 8-20, p<10-15 and IGFBP-6 (5th quintile ORs: 3-148, p<10-3. IGFBP-3 has a negative association with T1D complications (5th quintile ORs: 0.12-0.25, p<10-5. Conclusions: we found that elevated serum levels of IGFBP-1, 2 and 6 were associated with T1D and its complications and IGFBP-3 level was found to be decreased in T1D with complications. Given the known role of these IGFBPs, the overall impact of these alterations suggest a negative effect on IGF signaling.

  5. IGF-1, IGFBP-1, and IGFBP-3 polymorphisms predict circulating IGF levels but not breast cancer risk: findings from the Breast and Prostate Cancer Cohort Consortium (BPC3.

    Directory of Open Access Journals (Sweden)

    Alpa V Patel

    Full Text Available IGF-1 has been shown to promote proliferation of normal epithelial breast cells, and the IGF pathway has also been linked to mammary carcinogenesis in animal models. We comprehensively examined the association between common genetic variation in the IGF1, IGFBP1, and IGFBP3 genes in relation to circulating IGF-I and IGFBP-3 levels and breast cancer risk within the NCI Breast and Prostate Cancer Cohort Consortium (BPC3. This analysis included 6,912 breast cancer cases and 8,891 matched controls (n = 6,410 for circulating IGF-I and 6,275 for circulating IGFBP-3 analyses comprised primarily of Caucasian women drawn from six large cohorts. Linkage disequilibrium and haplotype patterns were characterized in the regions surrounding IGF1 and the genes coding for two of its binding proteins, IGFBP1 and IGFBP3. In total, thirty haplotype-tagging single nucleotide polymorphisms (htSNP were selected to provide high coverage of common haplotypes; the haplotype structure was defined across four haplotype blocks for IGF1 and three for IGFBP1 and IGFBP3. Specific IGF1 SNPs individually accounted for up to 5% change in circulating IGF-I levels and individual IGFBP3 SNPs were associated up to 12% change in circulating IGFBP-3 levels, but no associations were observed between these polymorphisms and breast cancer risk. Logistic regression analyses found no associations between breast cancer and any htSNPs or haplotypes in IGF1, IGFBP1, or IGFBP3. No effect modification was observed in analyses stratified by menopausal status, family history of breast cancer, body mass index, or postmenopausal hormone therapy, or for analyses stratified by stage at diagnosis or hormone receptor status. In summary, the impact of genetic variation in IGF1 and IGFBP3 on circulating IGF levels does not appear to substantially influence breast cancer risk substantially among primarily Caucasian postmenopausal women.

  6. GalNAc-T14 may be involved in regulating the apoptotic action of IGFBP-3.

    Science.gov (United States)

    Wu, Chen; Shan, Yaojun; Liu, Xinxia; Song, Wenqian; Wang, Jiali; Zou, Minji; Wang, Min; Xu, Donggang

    2009-09-01

    Insulin-like growth factor binding protein-3 (IGFBP-3) is known to induce apoptosis in an insulin-like growth factor (IGF)-dependent and IGF-independent manner, but the mechanism underlying the IGF-independent effects remains unclear. Polypeptide N-acetylgalactosaminyltransferase 14 (GalNAc-T14) is a novel IGFBP-3 binding partner. In this paper, small interference RNA (siRNA) targeting GalNAc-T14 was used to examine whether GalNAc-T14 affects the apoptotic action of IGFBP-3. Using semi-quantitative reverse-transcriptase polymerase chain reaction (RT-PCR) and western blot analysis, we determined that GalNAc-T14 expression was downregulated by the siRNA directed against GalNAc-T14. Apoptosis analysis of IGFBP-3-overexpressing cells treated with siRNA against GalNAc-T14 was performed to determine if GalNAc-T14 was specifically involved in IGFBP-3 signalling. The results, as determined by flow cytometric analysis and caspase-3 assay, showed that the extent of apoptosis induced by IGFBP-increased with RNA interference (RNAi) knockdown of GalNAc-T14. Our data suggest that GalNAc-T14 influences the apoptotic action of IGFBP-3 and might mediate the signalling pathway of IGFBP-3. Experiments to determine the role of GalNAc-T14 in the regulation of apoptosis induced by IGFBP-3 are under way.

  7. GalNAc-T14 may be involved in regulating the apoptotic action of IGFBP-3

    Indian Academy of Sciences (India)

    Chen Wu; Yaojun Shan; Xinxia Liu; Wenqian Song; Jiali Wang; Minji Zou; Min Wang; Donggang Xu

    2009-09-01

    Insulin-like growth factor binding protein-3 (IGFBP-3) is known to induce apoptosis in an insulin-like growth factor (IGF)-dependent and IGF-independent manner, but the mechanism underlying the IGF-independent effects remains unclear. Polypeptide -acetylgalactosaminyltransferase 14 (GalNAc-T14) is a novel IGFBP-3 binding partner. In this paper, small interference RNA (siRNA) targeting GalNAc-T14 was used to examine whether GalNAc-T14 affects the apoptotic action of IGFBP-3. Using semi-quantitative reverse-transcriptase polymerase chain reaction (RT-PCR) and western blot analysis, we determined that GalNAc-T14 expression was downregulated by the siRNA directed against GalNAc-T14. Apoptosis analysis of IGFBP-3-overexpressing cells treated with siRNA against GalNAc-T14 was performed to determine if GalNAc-T14 was specifically involved in IGFBP-3 signalling. The results, as determined by flow cytometric analysis and caspase-3 assay, showed that the extent of apoptosis induced by IGFBP-3 increased with RNA interference (RNAi) knockdown of GalNAc-T14. Our data suggest that GalNAc-T14 influences the apoptotic action of IGFBP-3 and might mediate the signalling pathway of IGFBP-3. Experiments to determine the role of GalNAc-T14 in the regulation of apoptosis induced by IGFBP-3 are under way.

  8. IGFBP-3, hypoxia and TNF-{alpha} inhibit adiponectin transcription

    Energy Technology Data Exchange (ETDEWEB)

    Zappala, Giovanna, E-mail: zappalag@mail.nih.gov [Diabetes Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD (United States); Rechler, Matthew M. [Diabetes Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD (United States); Clinical Endocrinology Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD (United States)

    2009-05-15

    The thiazolidinedione rosiglitazone, an agonist ligand for the nuclear receptor PPAR-{gamma}, improves insulin sensitivity in part by stimulating transcription of the insulin-sensitizing adipokine adiponectin. It activates PPAR-{gamma}-RXR-{alpha} heterodimers bound to PPAR-{gamma} response elements in the adiponectin promoter. Rosiglitazone-stimulated adiponectin protein synthesis in 3T3-L1 mouse adipocytes has been shown to be inhibited by IGFBP-3, which can be induced by hypoxia and the proinflammatory cytokine, TNF-{alpha}, two inhibitors of adiponectin transcription. The present study demonstrates that IGFBP-3, the hypoxia-mimetic agent cobalt chloride, and TNF-{alpha} inhibit rosiglitazone-induced adiponectin transcription in mouse embryo fibroblasts that stably express PPAR-{gamma}2. Native IGFBP-3 can bind RXR-{alpha} and inhibited rosiglitazone stimulated promoter activity, whereas an IGFBP-3 mutant that does not bind RXR-{alpha} did not. These results suggest that IGFBP-3 may mediate the inhibition of adiponectin transcription by hypoxia and TNF-{alpha}, and that IGFBP-3 binding to RXR-{alpha} may be required for the observed inhibition.

  9. Elevation of insulin-like growth factor binding protein-2 level in Pallister-Killian syndrome: implications for the postnatal growth retardation phenotype.

    Science.gov (United States)

    Izumi, Kosuke; Kellogg, Emily; Fujiki, Katsunori; Kaur, Maninder; Tilton, Richard K; Noon, Sarah; Wilkens, Alisha; Shirahige, Katsuhiko; Krantz, Ian D

    2015-06-01

    Pallister-Killian syndrome (PKS) is a multi-system developmental disorder caused by tetrasomy 12p that exhibits tissue-limited mosaicism. Probands with PKS often demonstrate a unique growth profile consisting of macrosomia at birth with deceleration of growth postnatally. We have previously demonstrated that cultured skin fibroblasts from PKS probands have significantly elevated expression of insulin-like growth factor binding protein-2 (IGFBP2). To further evaluate the role of IGFBP2 in PKS, the amount of IGFBP2 secreted from cultured skin fibroblast cell lines and serum IGFBP2 levels were measured in probands with PKS. Approximately 60% of PKS fibroblast cell lines secreted higher levels of IGFBP2 compared to control fibroblasts, although the remaining 40% of PKS samples produced comparable level of IGFBP2 to that of control fibroblasts. Serum IGFBP2 levels were also measured in PKS probands and were elevated in 40% of PKS probands. PKS probands with elevated IGFBP2 manifested with severe postnatal growth retardation. IGFBPs are the family of related proteins that bind IGFs with high affinity and are typically thought to attenuate IGF action. We suggest that elevated IGFBP2 levels might play a role in the growth retardation phenotype of PKS.

  10. Insulin-like growth factors, insulin-like growth factor-binding proteins, insulin-like growth factor-binding protein-3 protease, and growth hormone-binding protein in lipodystrophic human immunodeficiency virus-infected patients

    DEFF Research Database (Denmark)

    Haugaard, Steen B; Andersen, Ove; Hansen, Birgitte R;

    2004-01-01

    Human immunodeficiency virus (HIV)-lipodystrophy is associated with impaired growth hormone (GH) secretion. It remains to be elucidated whether insulin-like growth factors (IGFs), IGF-binding proteins (IGFBPs), IGFBP-3 protease, and GH-binding protein (GHBP) are abnormal in HIV-lipodystrophy. The......Human immunodeficiency virus (HIV)-lipodystrophy is associated with impaired growth hormone (GH) secretion. It remains to be elucidated whether insulin-like growth factors (IGFs), IGF-binding proteins (IGFBPs), IGFBP-3 protease, and GH-binding protein (GHBP) are abnormal in HIV......-lipodystrophy. These parameters were measured in overnight fasting serum samples from 16 Caucasian males with HIV-lipodystrophy (LIPO) and 15 Caucasian HIV-infected males without lipodystrophy (NONLIPO) matched for age, weight, duration of HIV infection, and antiretroviral therapy. In LIPO, abdominal fat mass and insulin...... study groups, including suppressed GH, and increased GHBP in LIPO, argue against GH resistance of GH-sensitive tissues in LIPO compared with NONLIPO; however, this notion awaits examination in dose-response studies. Furthermore, our data suggest that IGFBP-3 protease is a significant regulator...

  11. Identification of IGFBP-3 fragments generated by KLK2 and prevention of fragmentation by KLK2-inhibiting peptides.

    Science.gov (United States)

    Hekim, Can; Riipi, Tero; Weisell, Janne; Närvänen, Ale; Koistinen, Riitta; Stenman, Ulf-Håkan; Koistinen, Hannu

    2010-04-01

    Kallikrein-related peptidase 2 (KLK2) degrades insulin-like growth factor (IGF)-binding protein-3 (IGFBP-3) in vitro. IGFBP-3 forms complexes with IGFs, preventing them from binding to their receptors and stimulating cell proliferation and survival. IGF-independent actions have also been described for IGFBP-3. The degradation of IGFBP-3 by KLK2 or other proteases in the prostate may promote the growth of prostate cancer. We studied IGFBP-3 degradation by immunoblotting and two specific immunoassays, one recognizing only native non-fragmented IGFBP-3 and the other one recognizing both intact and proteolytically cleaved IGFBP-3. Peptides were used to inhibit the enzyme activity of KLK2 and cleavage sites in IGFBP-3 were identified by mass spectrometry. KLK2 proteolyzed IGFBP-3 into several small fragments, mostly after Arg residues, in keeping with the trypsin-like activity of KLK2. The fragmentation could be inhibited by KLK2-inhibiting peptides in a dose-dependent fashion. As degradation of IGFBP-3 could lead to a more aggressive cancer phenotype, inhibition of KLK2 activity might be useful for treatment of prostate cancer and other diseases associated with increased KLK2 activity.

  12. IGFBP-3 inhibits TNF-α production and TNFR-2 signaling to protect against retinal endothelial cell apoptosis.

    Science.gov (United States)

    Zhang, Qiuhua; Steinle, Jena J

    2014-09-01

    In models of diabetic retinopathy, insulin-like growth factor binding protein-3 (IGFBP-3) protects against tumor necrosis factors-alpha (TNF-α)-mediated apoptosis of retinal microvascular endothelial cells (REC), but the underlying mechanisms are unclear. Our current findings suggest that at least two discrete but complimentary pathways contribute to the protective effects of IGFBP-3; 1) IGFBP-3 directly activates the c-Jun kinase/tissue inhibitor of metalloproteinase-3/TNF-α converting enzyme (c-Jun/TIMP-3/TACE), pathway, which in turn inhibits TNF-α production; 2) IGFBP-3 acts through the IGFBP-3 receptor, low-density lipoprotein receptor-related protein 1 (LRP1), to inhibit signaling of TNF-α receptor 2 (TNFR2). Combined, these two IGFBP-3 pathways substantially reduce REC apoptosis and offer potential targets for the treatment of diabetic retinopathy.

  13. IGFBP3 colocalizes with and regulates hypocretin (orexin.

    Directory of Open Access Journals (Sweden)

    Makoto Honda

    Full Text Available BACKGROUND: The sleep disorder narcolepsy is caused by a vast reduction in neurons producing the hypocretin (orexin neuropeptides. Based on the tight association with HLA, narcolepsy is believed to result from an autoimmune attack, but the cause of hypocretin cell loss is still unknown. We performed gene expression profiling in the hypothalamus to identify novel genes dysregulated in narcolepsy, as these may be the target of autoimmune attack or modulate hypocretin gene expression. METHODOLOGY/PRINCIPAL FINDINGS: We used microarrays to compare the transcriptome in the posterior hypothalamus of (1 narcoleptic versus control postmortem human brains and (2 transgenic mice lacking hypocretin neurons versus wild type mice. Hypocretin was the most downregulated gene in human narcolepsy brains. Among many additional candidates, only one, insulin-like growth factor binding protein 3 (IGFBP3, was downregulated in both human and mouse models and co-expressed in hypocretin neurons. Functional analysis indicated decreased hypocretin messenger RNA and peptide content, and increased sleep in transgenic mice overexpressing human IGFBP3, an effect possibly mediated through decreased hypocretin promotor activity in the presence of excessive IGFBP3. Although we found no IGFBP3 autoantibodies nor a genetic association with IGFBP3 polymorphisms in human narcolepsy, we found that an IGFBP3 polymorphism known to increase serum IGFBP3 levels was associated with lower CSF hypocretin-1 in normal individuals. CONCLUSIONS/SIGNIFICANCE: Comparison of the transcriptome in narcolepsy and narcolepsy model mouse brains revealed a novel dysregulated gene which colocalized in hypocretin cells. Functional analysis indicated that the identified IGFBP3 is a new regulator of hypocretin cell physiology that may be involved not only in the pathophysiology of narcolepsy, but also in the regulation of sleep in normal individuals, most notably during adolescence. Further studies are

  14. Insulin-like growth factors, insulin-like growth factor-binding proteins, insulin-like growth factor-binding protein-3 protease, and growth hormone-binding protein in lipodystrophic human immunodeficiency virus-infected patients

    DEFF Research Database (Denmark)

    Haugaard, Steen B; Andersen, Ove; Hansen, Birgitte Rønde;

    2004-01-01

    Human immunodeficiency virus (HIV)-lipodystrophy is associated with impaired growth hormone (GH) secretion. It remains to be elucidated whether insulin-like growth factors (IGFs), IGF-binding proteins (IGFBPs), IGFBP-3 protease, and GH-binding protein (GHBP) are abnormal in HIV-lipodystrophy....... These parameters were measured in overnight fasting serum samples from 16 Caucasian males with HIV-lipodystrophy (LIPO) and 15 Caucasian HIV-infected males without lipodystrophy (NONLIPO) matched for age, weight, duration of HIV infection, and antiretroviral therapy. In LIPO, abdominal fat mass and insulin...... of bioactive IGF-I in HIV-lipodystrophy....

  15. Age-Related Insulin-Like Growth Factor Binding Protein-4 Overexpression Inhibits Osteogenic Differentiation of Rat Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Jinhui Wu

    2017-06-01

    Full Text Available Background/Aims: Insulin-like growth factor binding proteins (IGFBP play important roles in bone metabolism. IGFBP4 is involved in senescent-associated phenomena in mesenchymal stem cells (MSCs. The goal of the present study was to determine whether age-related IGFBP4 overexpression is associated with the impaired osteogenic differentiation potential of aged bone marrow derived MSCs. Methods: MSCs were isolated from Sprague-Dawley rats aged 3–26 months. The bone morphogenetic protein (BMP-2-induced osteogenic differentiation of rat MSCs was assessed by analyzing the expression levels of osteoblast marker genes [runt-related transcription factor 2 (RUNX2, alkaline phosphatase (ALP, and osteocalcin (OC], ALP activity and calcification. Results: Our study showed that IGFBP4 mRNA and protein expression increased with age in parallel with impaired osteogenic differentiation of MSCs cultured in BMP2-containing osteogenic medium, as evidenced by the downregulation of osteoblast marker genes, and decreased ALP activity and calcium deposits. IGFBP4 overexpression impaired BMP2-induced osteogenic differentiation potential of young MSCs, whereas IGFBP4 knockdown restored the osteogenic potency of aged MSCs. Moreover, IGFBP4 knockdown stimulated the activation of Erk and Smad by increasing phosphorylation. Conclusion: Collectively, our results demonstrate that IGFBP4 overexpression plays a role in the impairment of MSC differentiation potential via the Erk and Smad pathways, suggesting potential targets to improve MSC function for cell therapy applications.

  16. PPARγ induces growth inhibition and apoptosis through upregulation of insulin-like growth factor-binding protein-3 in gastric cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S.Y. [Department of Pediatrics, Chonbuk National University Hospital, Jeonju (Korea, Republic of); Biomedical Research Institute, School of Medicine, Chonbuk National University Hospital, Jeonju (Korea, Republic of); Kim, M.S.; Lee, M.K. [Department of Pediatrics, Chonbuk National University Hospital, Jeonju (Korea, Republic of); Kim, J.S.; Yi, H.K. [Department of Biochemistry, School of Dentistry, Chonbuk National University, Jeonju (Korea, Republic of); Nam, S.Y. [Department of Alternative Therapy, Jeonju University, Jeonju (Korea, Republic of); Lee, D.Y.; Hwang, P.H. [Department of Pediatrics, Chonbuk National University Hospital, Jeonju (Korea, Republic of); Biomedical Research Institute, School of Medicine, Chonbuk National University Hospital, Jeonju (Korea, Republic of)

    2015-01-13

    Peroxisome proliferator activator receptor-gamma (PPARγ) is a ligand-activated transcriptional factor involved in the carcinogenesis of various cancers. Insulin-like growth factor-binding protein-3 (IGFBP-3) is a tumor suppressor gene that has anti-apoptotic activity. The purpose of this study was to investigate the anticancer mechanism of PPARγ with respect to IGFBP-3. PPARγ was overexpressed in SNU-668 gastric cancer cells using an adenovirus gene transfer system. The cells in which PPARγ was overexpressed exhibited growth inhibition, induction of apoptosis, and a significant increase in IGFBP-3 expression. We investigated the underlying molecular mechanisms of PPARγ in SNU-668 cells using an IGFBP-3 promoter/luciferase reporter system. Luciferase activity was increased up to 15-fold in PPARγ transfected cells, suggesting that PPARγ may directly interact with IGFBP-3 promoter to induce its expression. Deletion analysis of the IGFBP-3 promoter showed that luciferase activity was markedly reduced in cells without putative p53-binding sites (-Δ1755, -Δ1795). This suggests that the critical PPARγ-response region is located within the p53-binding region of the IGFBP-3 promoter. We further demonstrated an increase in PPARγ-induced luciferase activity even in cells treated with siRNA to silence p53 expression. Taken together, these data suggest that PPARγ exhibits its anticancer effect by increasing IGFBP-3 expression, and that IGFBP-3 is a significant tumor suppressor.

  17. Hyperglycaemia-induced chemoresistance of prostate cancer cells due to IGFBP2.

    Science.gov (United States)

    Biernacka, K M; Uzoh, C C; Zeng, L; Persad, R A; Bahl, A; Gillatt, D; Perks, C M; Holly, J M P

    2013-10-01

    Clinically relevant prostate cancer (PCa) is more frequent in Westernised societies and increasingly men have co-morbidities associated with a Western lifestyle, primarily diabetes, characterised by hyperinsulinaemia and hyperglycaemia. IGFs and their binding proteins (IGFBPs) are important mediators of the effects of nutrition on growth and play a key role in the development of PCa. We used DU145, PC3 and LNCaP PCa cell lines to examine how hyperglycaemia altered their response to docetaxel. Trypan Blue dye-exclusion assay was used to determine the percentage of cell death. Protein abundance was determined using western immunoblotting. Levels of IGFBP2 were measured using an ELISA. IGFBP2 gene silencing was achieved using siRNA technology. DNA methylation was assessed using combined bisulphide restriction analysis. Acetylation status of histones H3 and H4 associated with IGFBP2 gene was assessed using chromatin immunoprecipitation assay. Hyperglycaemia reduced docetaxel-induced apoptosis by 40% for DU145 cells and by 88% for LNCaP cells. This reduced cell death was mediated by a glucose-induced up-regulation of IGFBP2, as silencing IGFBP2 negated the survival effect of high glucose. Glucose increased IGFBP2 via increasing the acetylation of histones associated with the IGFBP2 gene promoter. This finding could have important implications in relation to therapeutic strategies as epigenetic modulation could be reversible.

  18. Differential expression of serum glycodelin and insulin-like growth factor binding protein 1 in early pregnancy.

    Science.gov (United States)

    Douglas, Nataki C; Thornton, Melvin H; Nurudeen, Sahadat K; Bucur, Maria; Lobo, Rogerio A; Sauer, Mark V

    2013-11-01

    This prospective study evaluated whether serum glycodelin and insulin-like growth factor binding protein 1 (IGFBP-1) predict the likelihood of embryo implantation in recipients undergoing donor egg in vitro fertilization. We measured glycodelin and IGFBP-1 at 6 points from lining check to lutenizing hormone (LH) + 31. β-Human chorionic gonadotropin levels were first measured at LH + 17. The recipients were divided into those without embryo implantation (group 1, n = 6) and those with successful implantation (group 2, n = 30). Although this is a negative study in that neither glycodelin nor IGFBP-1 alone reflected endometrial (EM) receptivity, the glycodelin/IGFBP-1 ratio on the day of blastocyst transfer was higher in recipients who achieved pregnancy (P = .05). At LH + 17, glycodelin was higher (P = .04), and IGFBP-1 was lower (P = .004) in recipients who achieved pregnancy when compared to those who did not. These observations are likely due to EM changes induced by successful embryo implantation.

  19. Functional roles and clinical values of insulin-like growth factor-binding protein-5 in different types of cancers

    Institute of Scientific and Technical Information of China (English)

    G(o)k(c)e Güllü; Sevgi Karabulut; Mustafa Akkiprik

    2012-01-01

    Insulin-like growth factor-binding proteins (IGFBPs) are critical regulators of the mitogenic activity of insulin-like growth factors (IGFs).IGFBP5,one of these IGFBPs,has special structural features,including a nuclear transport domain,heparin-binding motif,and IGF/extracellular matrix/acid-labile subunit-binding sites.Furthermore,IGFBP5 has several functional effects on carcinogenesis and even normal cell processes,such as cell growth,death,motility,and tissue remodeling.These biological effects are sometimes related with IGF (IGF-dependent effects) and sometimes not (IGF-independent effects).The functional role of IGFBP5 is most likely determined in a cell-type and tissue-type specific manner but also depends on cell context,especially in terms of the diversity of interacting proteins and the potential for nuclear localization.Clinical findings show that IGFBP5 has the potential to be a useful clinical biomarker for predicting response to therapy and clinical outcome of cancer patients.In this review,we summarize the functional diversity and clinical importance of IGFBP5 in different types of cancers.

  20. Insulin-like growth factor binding protein 1 and human embryonic development during 6-10 gestational weeks

    Institute of Scientific and Technical Information of China (English)

    方群; 王艳霞; 周祎

    2004-01-01

    Background Insulin-like growth factor binding protein-1 (IGFBP-1), which is a carrier of Insulin-like growth factors (IGFs) regulates the fetal development by working as an active factor controlling the combination of IGFs with their receptors. This study was designed to investigate the relationship between IGFBP-1 and human embryonic development during weeks 6 -10 of gestation.Methods A total of 44 pregnant women with singleton pregnancy were divided into two groups: one with abnormal embryo development (n = 32) and the other with normal embryo development (n = 12).Enzyme-linked immunosorbent assay (ELISA) was employed to detect IGFBP-1 levels in maternal serum and decidual tissue. The expression of IGFBP-1 mRNA in deciduas was examined by reverse transcription polymerase chain reaction (RT-PCR) technique.Results The level of IGFBP-1 protein in maternal serum was significantly higher in the abnormal group [ (125.36 ± 47.93) μg/ml] than in the normal group [(70.72 ± 21.21) μg/ml ]. Both of IGFBP-1 and IGFBP-1 mRNA in deciduas were higher in abnormal group [ (1.60 ± 1.39) μg/ml and 1.66 ± 1.64, respectively ] than in the normal group [ (0.35 ± 0.23) μg/mi and 0.40 ± 0.20,respectively]. The level of IGFBP-1 in maternal serum was positively correlated with IGFBP-1 mRNA (r=0. 90, P<0.05) and IGFBP-1 protein (r=0.92, P<0.05) in decidual tissue.Conclusions During weeks 6 -10 of gestation, abnormal embryonic development is correlated with elevated IGFBP-1. The level of IGFBP-1 in maternal serum is related to the concentrations of IGFBP1 mRNA and IGFBP-1 in decidual tissue. The IGFBP-1 level in maternal serum may be used as a predictive marker to evaluate embryonic development.

  1. Insulin-like growth factor binding protein-5 influences pancreatic cancer cell growth

    Institute of Scientific and Technical Information of China (English)

    Sarah K Johnson; Randy S Haun

    2009-01-01

    AIM: To investigate the functional significance of insulin-like growth factor binding protein-5 (IGFBP-5) overexpression in pancreatic cancer (PaC).METHODS: The effects of IGFBP-5 on cell growth were assessed by stable transfection of BxPC-3 and PANC-1 cell lines and measuring cell number and DNA synthesis. Alterations in the cell cycle were assessed by flow cytometry and immunoblot analyses.Changes in cell survival and signal transduction were evaluated after mitogen activated protein kinase and phosphatidylinositol 3-kinase (PI3K) inhibitor treatment.RESULTS: After serum depr ivat ion, IGFBP-5 expression increased both cell number and DNA synthesis in BxPC-3 cells, but reduced cell number in PANC-1 cells. Consistent with this observation, cell cycle analysis of IGFBP-5-expressing cells revealed accelerated cell cycle progression in BxPC-3 and G2/M arrest of PANC-1 cells. Signal transduction analysis revealed that Akt activation was increased in BxPC-3, but reduced in PANC-1 cells that express IGFBP-5. Inhibition of PI3K with LY294002 suppressed extracellular signal-regulated kinase-1 and -2 (ERK1/2) activation in BxPC-3, but enhanced ERK1/2 activation in PANC-1 cells that express IGFBP-5. When MEK1/2 was blocked, Akt activation remained elevated in IGFBP-5 expressing PaC cells; however, inhibition of PI3K or MEK1/2 abrogated IGFBP-5-mediated cell survival.CONCLUSION: These results indicate that IGFBP-5 expression affects the cell cycle and survival signal pathways and thus it may be an important mediator of PaC cell growth.

  2. Modulation of IGFBP2 mRNA expression in white adipose tissue upon aging and obesity.

    Science.gov (United States)

    Li, Z; Picard, F

    2010-10-01

    The insulin/IGF-1 signaling pathway is a determinant of aging and age-related diseases. IGF-binding protein 2 (IGFBP2) is secreted by white adipocytes and contributes to the prevention of diet-induced obesity and age-related insulin resistance in mice. However, the expression levels of IGFBP2 in insulin resistance disorders have not been evaluated. The present study was aimed at determining IGFBP2 mRNA levels in adipose tissue in conditions of insulin resistance such as aging and obesity. In visceral white adipose tissue (WAT), but not in subcutaneous WAT, IGFBP2 mRNA levels were significantly lower in obese OB/OB, DB/DB and high fat-fed mice compared with those of their respective lean and chow-fed littermates. IGFBP2 mRNA levels were also decreased in visceral WAT of 12 and 24 months old mice compared with those of their 4 months old counterparts. Visceral WAT IGFBP2 expression was significantly associated with IGFBP2 circulating levels in mice, suggesting an important contribution from this tissue. The negative effect of aging on IGFBP2 mRNA levels in visceral WAT was confirmed in obese men. These findings demonstrate that the transcription of the IGFBP2 gene is modulated in a depot-specific fashion in obesity and aging in mice and men. Because IGFBP2 is an adipokine, an altered production from visceral WAT depots could impact on IGF-1 signaling and its downstream targets. This supports the need for further molecular and clinical studies to determine the factors regulating IGFBP2 expression and its relevance to metabolic diseases.

  3. Insulin-like growth factor binding protein-3 affects osteogenic efficacy on dental implants in rat mandible

    Energy Technology Data Exchange (ETDEWEB)

    Bhattarai, Govinda; Lee, Young-Hee [Department of Oral Biochemistry, Institute of Oral Bioscience, School of Dentistry, Chonbuk National University, Jeonju (Korea, Republic of); Lee, Min-Ho [Department of Dental Materials, Institute of Oral Bioscience, School of Dentistry, Chonbuk National University, Jeonju (Korea, Republic of); Park, Il-Song [Division of Advanced Materials Engineering, Research Center for Advanced Materials, Development and Institute of Biodegradable Materials, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Yi, Ho-Keun, E-mail: yihokn@chonbuk.ac.kr [Department of Oral Biochemistry, Institute of Oral Bioscience, School of Dentistry, Chonbuk National University, Jeonju (Korea, Republic of)

    2015-10-01

    Insulin like growth factor binding protein-3 (IGFBP-3) in bone cells and its utilization in dental implants have not been well studied. The aim of this study was to determine the osteogenic efficacy of chitosan gold nanoparticles (Ch-GNPs) conjugated with IGFBP-3 coated titanium (Ti) implants. Ch-GNPs were conjugated with IGFBP-3 plasmid DNA through a coacervation process. Conjugation was cast over Ti surfaces, and cells were seeded on coated surfaces. For in vitro analysis the expression of different proteins was analyzed by immunoblotting. For in vivo analysis, Ch-GNP/IGFBP-3 coated implants were installed in rat mandibles. Four weeks post-implantation, mandibles were examined by microcomputed tomography (μCT), immunohistochemistry, hematoxylin & eosin and tartrate resistance acid phosphatase staining. In vitro overexpressed Ch-GNP/IGFBP-3 coated Ti surfaces was associated with activation of extracellular signal related kinase (ERK), inhibition of the stress activated protein c-Jun N-terminal kinase (JNK) and enhanced bone morphogenetic protein (BMP)-2 and 7 compared to control. Further, in vivo, Ch-GNP/IGFBP-3 coated implants were associated with inhibition of implant induced osteoclastogenesis molecules, receptor activator of nuclear factor kappa-B ligand (RANKL) and enhanced expression of osteogenic molecules including BMP2/7 and osteopontin (OPN). The μCT analysis demonstrated that IGFBP-3 increased the volume of newly formed bone surrounding the implants compared to control (n = 5; p < 0.05). These results support the view that IGFBP-3 overexpression diminishes osteoclastogenesis and enhances osteogenesis of Ti implants, and can serve as a potent molecule for the development of good implantation. - Highlights: • Chitosan gold nanoparticles were conjugated with IGFBP-3 and coated onto surface of the titanium implants for gene delivery to bone. • Implants were inserted in rat mandible for 4 weeks. • Parameters studied: histopathology and radiology.

  4. Expression of insulin-like growth factor binding protein-2 in gastric carcinoma and its relationship with cell proliferation

    Institute of Scientific and Technical Information of China (English)

    Liang-Hui Shi; Xiao-Qun Zhu; Guo-Hai Zhao; Ya-Bin Xia; Yi-Sheng Zhang

    2006-01-01

    AIM: To investigate the expression of insulin-like growth factor binding protein-2 (IGFBP-2) in gastric carcinoma and its clinical significance and to explore its relationship with cell proliferation.METHODS: Expressions of IGFBP-2 and Ki-67 in 118cases of gastric carcinoma and 40 cases of normal gastric mucosa were detected by EnVision immunohistochemical technique.RESULTS: Expression of IGFBP-2 in gastric carcinoma was higher than that in normal gastric mucosa (P 0.05). Fxpression of IGFBP-2 in aclvancecl gastric carcinoma was higher than that in early gastric carcinoma (P < 0.05). Expression of IGFBP-2 in gastric carcinoma with lymph node metastasis was higher than that without lymph node metastasis (P < 0.01).IGFBP-2 expression was a positively related to the clinical stage of gastric carcinoma (P < 0.01). There was a positive correlation between IGFBP-2 and Ki-67 (P < 0.05).CONCLUSION: IGFBP-2 may be involved in carcinogenesis and progression of gastric carcinoma by promoting cell proliferation.

  5. Sensitive and selective analysis of a wide concentration range of IGFBP7 using a surface plasmon resonance biosensor.

    Science.gov (United States)

    Jang, Dae-Ho; Choi, Youngbo; Choi, Yong-Soo; Kim, Sun-Mi; Kwak, Hojung; Shin, Se-Hyun; Hong, Surin

    2014-11-01

    A sensitive method for selectively detecting insulin-like growth factor-binding protein 7 (IGFBP7) over a wide range of concentrations based on the surface plasmon resonance (SPR) biosensing techniques is described. IGFBP7 has been shown to regulate cell proliferation, cell adhesion, cellular senescence, apoptosis, and angiogenesis in several different cancer cell lines. Since the concentration of IGFBP7 can vary widely in the body, determining the precise concentration of IGFBP7 over a wide range of concentrations is important, since it serves as an inducible biomarker for both disease diagnosis and subsequent therapy. The SPR sensing method is based on the selective interaction of IGFBP7 with specific anti-IGFBP7 proteins on a gold thin film, which was covalently bound to the Fc-binding domain of protein G on a mixed self-assembled monolayer composed of DSNHS (S2(CH2)11COO(CH2)2COO-(N-hydroxysuccinimide)) and mercaptoundecanol, and effect of this on changes in the SPR profiles. The limit of detection (LOD) of the SPR biosensor was determined to be 10 ng/ml, which is a reasonable LOD value for biomedical applications. The response is essentially linear in the concentration range of 10-300 ng/ml. The SPR biosensor also shows specificity for IGFBP7 compared to that for biologically relevant interleukin (IL) derivatives including IL4, IL23, IL29, and IFG1. These molecules are also present along with IGFBP7 in the cell culture medium and have the potential to interfere with the analysis. Finally, the level secretion of IGFBP7 from cancer cells detected by the SPR biosensor showed a good correlation with a commercial kit using an IGFBP7 enzyme-linked immunosorbent assay. The findings reported herein indicate that the SPR biosensor for IGFBP7 would be applicable in a wide variety of biomedical fields.

  6. Intravitreal injection of IGFBP-3 restores normal insulin signaling in diabetic rat retina.

    Directory of Open Access Journals (Sweden)

    Youde Jiang

    Full Text Available Diabetes-induced changes in growth factor binding protein 3 (IGFBP-3 and tumor necrosis factor alpha (TNFα have been linked to decreased insulin receptor signaling in diabetic retinopathy. Our previous studies in retinas of diabetic rats have shown that Compound 49b, a novel β-adrenergic receptor agonist, prevented diabetic changes by increasing IGFBP-3 and decreasing TNFα, thus restoring insulin signaling and protection against diabetic retinopathy. The current study was designed to determine whether boosted expression of IGFBP-3 NB (a non-IGF-1 binding form of IGFBP-3 alone is sufficient to mimic the full actions of Compound 49b in protecting against diabetic retinopathy, as well as testing whether IGFBP-3 NB is linked to a restoration of normal insulin signal transduction. Two months after initiation of streptozotocin-induced diabetes, rats received a single intravitreal injection of IGFBP-3 NB plasmid in the right eye. Four days after injection, electroretinogram (ERG analyses were performed prior to sacrifice. Whole retinal lysates from control, diabetic, diabetic + control plasmid, and diabetic+ IGFBP-3 NB were analyzed for IGFBP-3, TNFα, suppressor of cytokine signaling 3 (SOCS3, and insulin receptor signaling partners using Western blotting or ELISA. Data show that a single intraocular injection of IGFBP-3 NB in diabetic animals significantly reduced TNFα levels, concomitant with reductions in IRS-1Ser307, SOCS3, and pro-apoptotic markers, while restoring insulin receptor phosphorylation and increasing anti-apoptotic marker levels. These cellular changes were linked to restoration of retinal function. Our findings establish IGFBP-3 as a pivotal regulator of the insulin receptor/TNFα pathway and a potential therapeutic target for diabetic retinopathy.

  7. Measurement of intact insulin-like growth factor-binding protein-3 in human plasma using a ligand immunofunctional assay.

    Science.gov (United States)

    Lassarre, C; Binoux, M

    2001-03-01

    Limited proteolysis of insulin-like growth factor binding protein-3 (IGFBP-3) is a fundamental mechanism in the regulation of IGF-I bioavailability in the bloodstream. Its measurement by Western immunoblotting provides only semiquantitative estimation. We have developed a ligand immunofunctional assay (LIFA) for quantifying human (h) intact IGFBP-3 in biological fluids. IGFBP-bound IGFs are dissociated and separated by acid pH ultrafiltration, and a monoclonal antibody specific to the first 160 amino acids of IGFBP-3 is used to capture hIGFBP-3 in a solid-phase assay. The complex is then incubated with (125)I-IGF-I, which binds to intact IGFBP-3 but not to its proteolytic fragments. Binding specificity was demonstrated in competition experiments with unlabeled IGF. Nonspecific binding was 1.4%. The fragments comprising residues 1-160 and 1-95 of recombinant hIGFBP-3 [corresponding to the major proteolytic fragments of approximately 30 kDa and (glycosylated) 20 or (nonglycosylated) 16 kDa detected in serum by Western immunoblotting, respectively] fail to bind (125)I-IGF-I when complexed with the monoclonal antibody. Similarly, no binding of (125)I-IGF-I was obtained in the LIFA when applied to plasmas from pregnant women during the final 3 months of pregnancy, where the characteristic 42- to 39-kDa doublet of intact IGFBP-3 is undetectable. The standard curve was established using a pool of plasmas (EDTA) from healthy adults, for which standardization with glycosylated recombinant hIGFBP-3 yielded an intact IGFBP-3 content of 2 microg/mL. The dynamic range of the LIFA was 0.50-3.75 microL equivalent of the plasma pool in a total volume of 300 microL per assay tube, with a sensitivity threshold of approximately 1 ng intact IGFBP-3. Unknown plasma samples were studied at three concentrations. Intra- and interassay variations were 3.6% and 4%, respectively. In 31 healthy adults, the mean plasma concentration of intact IGFBP-3 was 2.24 +/- 0.08 (SEM) mg/L, and that of

  8. DHT and testosterone, but not DHEA or E2, differentially modulate IGF-I, IGFBP-2, and IGFBP-3 in human prostatic stromal cells.

    Science.gov (United States)

    Le, Hanh; Arnold, Julia T; McFann, Kimberly K; Blackman, Marc R

    2006-05-01

    Prostate cancer is one of the four most common cancers in the United States, affecting one of six men. Increased serum levels of androgens and IGF-I are associated with an augmented risk of prostate cancer. Dihydrotestosterone (DHT) and testosterone (T) stimulate prostate cancer cell growth, development, and function, whereas the effects of DHT and T in prostate stromal cells, and of dehydroepiandrosterone (DHEA) in prostate cancer or stromal cells, are uncertain. We investigated the actions of DHT, T, DHEA, and estradiol (E2) on insulin-like growth factor (IGF)-I, IGF-II, IGF-I receptor (R), IGF-binding protein (IGFBP)-2, IGFBP-3, and IGFBP-5 in primary cultures of human prostatic stromal cells by assessing cell proliferation, mRNA expression, and protein secretion by MTT growth assay, quantitative real-time PCR, and ELISA, respectively. DHT and T each increased IGF-I (7-fold) and decreased IGFBP-3 (2-fold) mRNA expression and protein secretion in a dose- and time-dependent manner and increased IGFBP-2 (2-fold) mRNA in a dose- and time-dependent manner. DHEA and E2 did not significantly alter these measures. Flutamide abolished the DHT-modulated increases in IGF-I and IGFBP-2, suggesting that the influences of DHT and T on these measures were androgen receptor mediated. None of the four steroids significantly affected IGF-IR, IGF-II, or IGFBP-5 mRNA levels or stromal cell proliferation. The effects of DHT on IGF-I, IGFBP-2, and IGFBP-3 were more pronounced in stromal cultures that did not express desmin. These data suggest that DHT and T promote prostate growth partly via modulation of the stromal cell IGF axis, with potential paracrine effects on prostate epithelial cells.

  9. Intrinsic, pro-apoptotic effects of IGFBP-3 on breast cancer cells are reversible: Involvement of PKA, Rho and ceramide.

    Directory of Open Access Journals (Sweden)

    Claire M Perks

    2011-05-01

    Full Text Available We established previously that IGFBP-3 could exert positive or negative effects on cell function depending upon the extracellular matrix composition and by interacting with integrin signalling. To elicit its pro-apoptotic effects IGFBP-3 bound to caveolin-1 and the beta 1 integrin receptor and increased their association culminating in MAPK activation. Disruption of these complexes or blocking the beta 1 integrin receptor reversed these intrinsic actions of IGFBP-3. In this study we have examined the signalling pathway between integrin receptor binding and MAPK activation that mediates the intrinsic, pro-apoptotic actions of IGFBP-3. We found on inhibiting protein kinase A(PKA, Rho associated kinase (ROCK and ceramide, the accentuating effects of IGFBP-3 on apoptotic triggers were reversed, such that IGFBP-3 then conferred cell survival. We established that IGFBP-3 activated Rho, the upstream regulator of ROCK and that beta1 integrin and PKA were upstream of Rho activation, whereas the involvement of ceramide was downstream. The beta 1 integrin, PKA, Rho and ceramide were all upstream of MAPK activation. These data highlight key components involved in the pro-apoptotic effects of IGFBP-3 and that inhibiting them leads to a reversal in the action of IGFBP-3.

  10. IGF-independent effects of IGFBP-2 on the human breast cancer cell line Hs578T.

    Science.gov (United States)

    Frommer, Klaus W; Reichenmiller, Katharina; Schutt, Burkhardt S; Hoeflich, Andreas; Ranke, Michael B; Dodt, Gabriele; Elmlinger, Martin W

    2006-08-01

    There is evidence that insulin-like growth factor-binding protein (IGFBP-2), a modulator of the actions of IGFs, also has IGF-independent effects in human tumor cell lines. These involve specific binding of IGFBP-2 to alpha5beta1-integrin, followed by alterations in the phosphorylation status of downstream signaling molecules. Previously, IGFBP-2 has also been shown to be associated with cell proliferation, adhesion and migration. Here, we investigated direct effects of IGFBP-2 on apoptosis and alterations in the expression of related proteins. The breast cancer cell line Hs578T, which shows no IGFBP-2 production of its own and is independent of the IGF-I receptor, was treated with human recombinant IGFBP-2 in order to study the changes in gene expression induced by IGFBP-2. The methods employed for this purpose were oligonucleotide microarrays, real-time RT-PCR, western blotting, and immunoassays. Out of the 440 genes covered by the Oligo GEArray Human Cancer Microarray OHS-802, the expression of 77 genes was directly influenced by IGFBP-2. By the use of real-time quantitative RT-PCR, the gene expression of Nuclear Factor (NF)kappaB, p53, transforming growth factor beta (TGF beta-1), LAMB1 (Laminin, Beta 1), Bcl-2, and IIp45 was found to be significantly upregulated (by 1.2- to 3.05-fold; all P 1.5-fold. By using an ELISA-based and a flow cytometry-based apoptosis assay, IGFBP-2 was found to have a pro-apoptotic effect on Hs578T cells. Our results suggest that IGFBP-2-induced gene expressions are of functional significance for proliferation, cell adhesion, cell migration and apoptosis, and showed that IGFBP-2 can promote apoptosis in tumor cells independent of IGF.

  11. Circulating insulin-like growth factor-binding protein 3 as prognostic biomarker in liver cirrhosis

    Institute of Scientific and Technical Information of China (English)

    Carina; Gabriela; Correa; Bruno; da; Silveira; Colombo; Marcelo; Fernando; Ronsoni; Pedro; Eduardo; Soares; e; Silva; Leonardo; Fayad; Telma; Erotides; Silva; Letícia; Muraro; Wildner; Maria; Luiza; Bazzo; Esther; Buzaglo; Dantas-Correa; Janaína; Luz; Narciso-Schiavon; Leonardo; de; Lucca; Schiavon

    2016-01-01

    AIM: To investigate the prognostic significance of insulin-like growth factor-binding protein 3(IGFBP-3) in patients with cirrhosis.METHODS: Prospective study that included two cohorts: outpatients with stable cirrhosis(n = 138) and patients hospitalized for acute decompensation(n = 189). Development of complications, mortality or liver transplantation was assessed by periodical phone calls and during outpatient visits. The cohort of stable cirrhosis also underwent clinical and laboratory evaluation yearly(2013 and 2014) in predefined study visits. In patients with stable cirrhosis, IGFBP-3 levels were measured at baseline(2012) and at second re-evaluation(2014). In hospitalized subjects, IGFBP-3 levels were measured in serum samples collected in the first and in the third day after admission and stored at-80 ℃. IGFBP-3 levels were measured by immunochemiluminescence.RESULTS: IGFBP-3 levels were lower in hospitalized patients as compared to outpatients(0.94 mcg/mL vs 1.69 mcg/m L, P < 0.001) and increased after liver transplantation(3.81 mcg/m L vs 1.33 mcg/mL, P = 0.008). During the follow-up of the stable cohort, 17 patients died and 11 received liver transplantation. Bivariate analysis showed that death or transplant was associated with lower IGFBP-3 levels(1.44 mcg/mL vs 1.74 mcg/m L, P = 0.027). The Kaplan-Meier transplant-free survival probability was 88.6% in patients with IGFBP-3 ≥ 1.67 mcg/mL and 72.1% for those with IGFBP3 < 1.67 mcg/mL(P = 0.015). In the hospitalized cohort, 30-d mortality was 24.3% and was independently associated with creatinine, INR, SpO2/FiO2 ratio and IGFBP-3 levels in the logistic regression. The 90-d transplant-free survival probability was 80.4% in patients with IGFBP-3 ≥ 0.86 mcg/mL and 56.1% for those with IGFBP3 < 0.86 mcg/mL(P < 0.001). CONCLUSION: Lower IGFBP-3 levels were associated with worse outcomes in patients with cirrhosis, and might represent a promising prognostic

  12. Antiproliferative action of tumor necrosis factor-alpha on MCF-7 breastcancer cells is associated with increased insulin-like growth factor binding protein-3 accumulation.

    Science.gov (United States)

    Rozen, F; Zhang, J; Pollak, M

    1998-10-01

    Tumor necrosis factor-alpha (TNF-alpha) is a multifunctional cytokine involved in host response to neoplasia. TNF-alpha has been shown to inhibit proliferation and induce apoptosis of MCF-7 breast carcinoma cells. Insulin-like growth factors I and II (IGF-I and IGF-II) are potent mitogens involved in growth regulation of breast epithelial cells and are implicated in the pathophysiology of breast cancer. Their bioactivity is strongly influenced by specific IGF-binding proteins (IGFBPs). We report that accumulation of IGFBP-3 in the conditioned media of MCF-7 cells is increased over control values in the presence of TNF-alpha. The increased IGFBP-3 accumulation induced by TNF-alpha is correlated with increased IGFBP-3 mRNA abundance. TNF-alpha also decreases IGF-I receptor levels in MCF-7 cells. Estradiol-stimulated MCF-7 cell proliferation is associated with reduced IGFBP-3 accumulation, and we show that TNF-alpha attenuation of estradiol-stimulated proliferation is associated with increased IGFBP-3 accumulation. Finally, we demonstrate that an IGFBP-3 antisense oligodeoxynucleotide antagonizes TNF-alpha-induced inhibition of cell proliferation and TNF-alpha-induced IGFBP-3 accumulation. These data strongly suggest that IGFBP-3 plays a role in modulation of breast cancer cell proliferation by TNF-alpha.

  13. Low serum levels of free and total insulin-like growth factor I (IGF-I) in patients with anorexia nervosa are not associated with increased IGF-binding protein-3 proteolysis

    DEFF Research Database (Denmark)

    Støving, R K; Flyvbjerg, A; Frystyk, J;

    1999-01-01

    Patients with anorexia nervosa (AN) are GH resistant, with elevated GH levels and low serum levels of total insulin-like growth factor I (IGF-I). IGF-I action is modulated by IGF-binding proteins (IGFBPs), and a variety of catabolic states has been characterized by the presence of increased IGFBP-3...

  14. A comprehensive analysis of common IGF1, IGFBP1 and IGFBP3 genetic variation with prospective IGF-I and IGFBP-3 blood levels and prostate cancer risk among Caucasians†

    Science.gov (United States)

    Schumacher, Fredrick R.; Cheng, Iona; Freedman, Matthew L.; Mucci, Lorelei; Allen, Naomi E.; Pollak, Michael N.; Hayes, Richard B.; Stram, Daniel O.; Canzian, Federico; Henderson, Brian E.; Hunter, David J.; Virtamo, Jarmo; Manjer, Jonas; Gaziano, J. Michael; Kolonel, Laurence N.; Tjønneland, Anne; Albanes, Demetrius; Calle, Eugenia E.; Giovannucci, Edward; Crawford, E. David; Haiman, Christopher A.; Kraft, Peter; Willett, Walter C.; Thun, Michael J.; Le Marchand, Loïc; Kaaks, Rudolf; Feigelson, Heather Spencer; Bueno-de-Mesquita, H. Bas; Palli, Domenico; Riboli, Elio; Lund, Eiliv; Amiano, Pilar; Andriole, Gerald; Dunning, Alison M.; Trichopoulos, Dimitrios; Stampfer, Meir J.; Key, Timothy J.; Ma, Jing

    2010-01-01

    The insulin-like growth factor (IGF) pathway has been implicated in prostate development and carcinogenesis. We conducted a comprehensive analysis, utilizing a resequencing and tagging single-nucleotide polymorphism (SNP) approach, between common genetic variation in the IGF1, IGF binding protein (BP) 1, and IGFBP3 genes with IGF-I and IGFBP-3 blood levels, and prostate cancer (PCa) risk, among Caucasians in the NCI Breast and Prostate Cancer Cohort Consortium. We genotyped 14 IGF1 SNPs and 16 IGFBP1/IGFBP3 SNPs to capture common [minor allele frequency (MAF) ≥ 5%] variation among Caucasians. For each SNP, we assessed the geometric mean difference in IGF blood levels (N = 5684) across genotypes and the association with PCa risk (6012 PCa cases/6641 controls). We present two-sided statistical tests and correct for multiple comparisons. A non-synonymous IGFBP3 SNP in exon 1, rs2854746 (Gly32Ala), was associated with IGFBP-3 blood levels (Padj = 8.8 × 10−43) after adjusting for the previously established IGFBP3 promoter polymorphism A-202C (rs2854744); IGFBP-3 blood levels were 6.3% higher for each minor allele. For IGF1 SNP rs4764695, the risk estimates among heterozygotes was 1.01 (99% CI: 0.90–1.14) and 1.20 (99% CI: 1.06–1.37) for variant homozygotes with overall PCa risk. The corrected allelic P-value was 8.7 × 10−3. IGF-I levels were significantly associated with PCa risk (Ptrend = 0.02) with a 21% increase of PCa risk when compared with the highest quartile to the lowest quartile. We have identified SNPs significantly associated with IGFBP-3 blood levels, but none of these alter PCa risk; however, a novel IGF1 SNP, not associated with IGF-I blood levels, shows preliminary evidence for association with PCa risk among Caucasians. PMID:20484221

  15. Interaction between Fibrinogen and Insulin-Like Growth Factor-Binding Protein-1 in Human Plasma under Physiological Conditions.

    Science.gov (United States)

    Gligorijević, N; Nedić, O

    2016-02-01

    Fibrinogen is a plasma glycoprotein and one of the principle participants in blood coagulation. It interacts with many proteins during formation of a blood clot, including insulin-like growth factors (IGFs) and their binding proteins (IGFBP). Fibrinogen complexes were found as minor fractions in fibrinogen preparations independently of the coagulation process, and their presence influences the kinetics of polymerization. The idea of this work was to investigate whether fibrinogen in human plasma interacts with IGFBPs independently of the tissue injury or coagulation process. The results have shown that fibrinogen forms complexes with IGFBP-1 under physiological conditions. Several experimental approaches have confirmed that complexes are co-isolated with fibrinogen from plasma, they are relatively stable, and they appear as a general feature of human plasma. Several other experiments excluded the possibility that alpha-2 macroglobulin/IGFBP-1 complexes or IGFBP-1 oligomers contributed to IGFBP-1 immunoreactivity. The role of fibrinogen/IGFBP-1 complexes is still unknown. Further investigation in individuals expressing both impaired glucose control and coagulopathy could contribute to identification and understanding of their possible physiological role.

  16. Insulin-Like Growth Factor Binding Protein-4 as a Marker of Chronic Lupus Nephritis.

    Directory of Open Access Journals (Sweden)

    Tianfu Wu

    Full Text Available Kidney biopsy remains the mainstay of Lupus Nephritis (LN diagnosis and prognostication. The objective of this study is to identify non-invasive biomarkers that closely parallel renal pathology in LN. Previous reports have demonstrated that serum Insulin-like growth factor binding protein 4 (IGFBP-4 was increased in diabetic nephropathy in both animal models and patients. We proceeded to assess if IGFBP4 could be associated with LN. We performed ELISA using the serum of 86 patients with LN. Normal healthy adults (N = 23 and patients with other glomerular diseases (N = 20 served as controls. Compared to the healthy controls or other glomerular disease controls, serum IGFBP-4 levels were significantly higher in the patients with LN. Serum IGFBP-4 did not correlate well with systemic lupus erythematosus disease activity index (SLEDAI, renal SLEDAI or proteinuria, but it did correlate with estimated glomerular filtration rate (R = 0.609, P < 0.0001. Interestingly, in 18 patients with proliferative LN whose blood samples were obtained at the time of renal biopsy, serum IGFBP-4 levels correlated strongly with the chronicity index of renal pathology (R = 0.713, P < 0.001. IGFBP-4 emerges a potential marker of lupus nephritis, reflective of renal pathology chronicity changes.

  17. Insulin-like growth factor-I and insulin-like growth factor-binding proteins in the nephrotic syndrome.

    Science.gov (United States)

    Feld, S M; Hirschberg, R

    1996-06-01

    Similar to findings in the nephrotic syndrome in humans, rats with the doxorubicin-induced nephrotic syndrome (which resembles minimal change disease) have reduced serum levels of insulin-like growth factor-I (IGF-I). This is mainly caused by glomerular ultrafiltration of IGF-I-containing binding protein complexes, primarily of a molecular weight of approximately 50 kilodaltons, and urinary losses of the peptide. Despite urinary excretion of IGF-binding protein (IGFBP)-2, serum levels are increased more than twofold in the nephrotic syndrome compared with controls, because of increased synthesis of this binding protein by the liver. In contrast, the liver synthesis of IGFBP-3, the predominant binding protein in normal serum, is unchanged in the nephrotic syndrome. However, binding and serum levels of IGFBP-3 are reduced in nephrotic rat serum, apparently due to proteolytic degradation of IGFBP-3. The glomerular ultrafiltration of IGF-I, which leads to biologically significant IGF-I concentrations of about 1.35 nM in proximal tubule fluid, may have metabolic consequences, such as increased tubular phosphate absorption. Hypothetically, tubule fluid IGF-I may also contribute to progressive tubulointerstitial fibrosis which is sometimes present in protractive nephrotic glomerulopathies. The profound changes in the IGF-I/IGFBP system in the nephrotic syndrome may also contribute to systemic metabolic abnormalities and growth failure.

  18. Hypoxia Suppresses Spontaneous Mineralization and Osteogenic Differentiation of Mesenchymal Stem Cells via IGFBP3 Up-Regulation

    Directory of Open Access Journals (Sweden)

    Ji Hye Kim

    2016-08-01

    Full Text Available Hypoxia has diverse stimulatory effects on human adipose-derived stem cells (ASCs. In the present study, we investigated whether hypoxic culture conditions (2% O2 suppress spontaneous mineralization and osteogenic differentiation of ASCs. We also investigated signaling pathways and molecular mechanisms involved in this process. We found that hypoxia suppressed spontaneous mineralization and osteogenic differentiation of ASCs, and up-regulated mRNA and protein expression of Insulin-like growth factor binding proteins (IGFBPs in ASCs. Although treatment with recombinant IGFBPs did not affect osteogenic differentiation of ASCs, siRNA-mediated inhibition of IGFBP3 attenuated hypoxia-suppressed osteogenic differentiation of ASCs. In contrast, overexpression of IGFBP3 via lentiviral vectors inhibited ASC osteogenic differentiation. These results indicate that hypoxia suppresses spontaneous mineralization and osteogenic differentiation of ASCs via intracellular IGFBP3 up-regulation. We determined that reactive oxygen species (ROS generation followed by activation of the MAPK and PI3K/Akt pathways play pivotal roles in IGFBP3 expression under hypoxia. For example, ROS scavengers and inhibitors for MAPK and PI3K/Akt pathways attenuated the hypoxia-induced IGFBP3 expression. Inhibition of Elk1 and NF-κB through siRNA transfection also led to down-regulation of IGFBP3 mRNA expression. We next addressed the proliferative potential of ASCs with overexpressed IGFBP3, but IGFBP3 overexpression reduced the proliferation of ASCs. In addition, hypoxia reduced the osteogenic differentiation of bone marrow-derived clonal mesenchymal stem cells. Collectively, our results indicate that hypoxia suppresses the osteogenic differentiation of mesenchymal stem cells via IGFBP3 up-regulation.

  19. IGFBP-4 tumor and serum levels are increased across all stages of epithelial ovarian cancer

    Directory of Open Access Journals (Sweden)

    Mosig Rebecca A

    2012-01-01

    Full Text Available Abstract Background We sought to identify candidate serum biomarkers for the detection and surveillance of EOC. Based on RNA-Seq transcriptome analysis of patient-derived tumors, highly expressed secreted proteins were identified using a bioinformatic approach. Methods RNA-Seq was used to quantify papillary serous ovarian cancer transcriptomes. Paired end sequencing of 22 flash frozen tumors was performed. Sequence alignments were processed with the program ELAND, expression levels with ERANGE and then bioinformatically screened for secreted protein signatures. Serum samples from women with benign and malignant pelvic masses and serial samples from women during chemotherapy regimens were measured for IGFBP-4 by ELISA. Student's t Test, ANOVA, and ROC curves were used for statistical analysis. Results Insulin-like growth factor binding protein (IGFBP-4 was consistently present in the top 7.5% of all expressed genes in all tumor samples. We then screened serum samples to determine if increased tumor expression correlated with serum expression. In an initial discovery set of 21 samples, IGFBP-4 levels were found to be elevated in patients, including those with early stage disease and normal CA125 levels. In a larger and independent validation set (82 controls, 78 cases, IGFBP-4 levels were significantly increased (p -5. IGFBP-4 levels were ~3× greater in women with malignant pelvic masses compared to women with benign masses. ROC sensitivity was 73% at 93% specificity (AUC 0.816. In women receiving chemotherapy, average IGFBP-4 levels were below the ROC-determined threshold and lower in NED patients compared to AWD patients. Conclusions This study, the first to our knowledge to use RNA-Seq for biomarker discovery, identified IGFBP-4 as overexpressed in ovarian cancer patients. Beyond this, these studies identified two additional intriguing findings. First, IGFBP-4 can be elevated in early stage disease without elevated CA125. Second, IGFBP-4

  20. A scallop IGF binding protein gene: molecular characterization and association of variants with growth traits.

    Directory of Open Access Journals (Sweden)

    Liying Feng

    Full Text Available BACKGROUND: Scallops represent economically important aquaculture shellfish. The identification of genes and genetic variants related to scallop growth could benefit high-yielding scallop breeding. The insulin-like growth factor (IGF system is essential for growth and development, with IGF binding proteins (IGFBPs serving as the major regulators of IGF actions. Although an effect of IGF on growth was detected in bivalve, IGFBP has not been reported, and members of the IGF system have not been characterized in scallop. RESULTS: We cloned and characterized an IGFBP (PyIGFBP gene from the aquaculture bivalve species, Yesso scallop (Patinopecten yessoensis, Jay, 1857. Its full-length cDNA sequence was 1,445 bp, with an open reading frame of 378 bp, encoding 125 amino acids, and its genomic sequence was 10,193 bp, consisting of three exons and two introns. The amino acid sequence exhibited the characteristics of IGFBPs, including multiple cysteine residues and relatively conserved motifs in the N-terminal and C-terminal domains. Expression analysis indicated that PyIGFBP was expressed in all the tissues and developmental stages examined, with a significantly higher level in the mantle than in other tissues and a significantly higher level in gastrulae and trochophore larvae than in other stages. Furthermore, three single nucleotide polymorphisms (SNPs were identified in this gene. SNP c.1054A>G was significantly associated with both shell and soft body traits in two populations, with the highest trait values in GG type scallops and lowest in AG type ones. CONCLUSION: We cloned and characterized an IGFBP gene in a bivalve, and this report also represents the first characterizing an IGF system gene in scallops. A SNP associated with scallop growth for both the shell and soft body was identified in this gene. In addition to providing a candidate marker for scallop breeding, our results also suggest the role of PyIGFBP in scallop growth.

  1. Mxi1 regulates cell proliferation through insulin-like growth factor binding protein-3

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Je Yeong; Yoo, Kyung Hyun [Department of Biological Science, Sookmyung Women' s University, Seoul (Korea, Republic of); Lee, Han-Woong [Department of Biochemistry, Yonsei University, Seoul (Korea, Republic of); Park, Jong Hoon, E-mail: parkjh@sookmyung.ac.kr [Department of Biological Science, Sookmyung Women' s University, Seoul (Korea, Republic of)

    2011-11-11

    Highlights: Black-Right-Pointing-Pointer Mxi1 regulates cell proliferation. Black-Right-Pointing-Pointer Expression of IGFBP-3 is regulated by Mxi1. Black-Right-Pointing-Pointer Inactivation of Mxi1 reduces IGFBP-3 expression in vitro and in vivo. -- Abstract: Mxi1, a member of the Myc-Max-Mad network, is an antagonist of the c-Myc oncogene and is associated with excessive cell proliferation. Abnormal cell proliferation and tumorigenesis are observed in organs of Mxi1-/- mice. However, the Mxi1-reltaed mechanism of proliferation is unclear. The present study utilized microarray analysis using Mxi1 mouse embryonic fibroblasts (MEFs) to identify genes associated with cell proliferation. Among these genes, insulin-like growth factor binding protein-3 (IGFBP-3) was selected as a candidate gene for real-time PCR to ascertain whether IGFBP-3 expression is regulated by Mxi1. Expression of IGFBP-3 was decreased in Mxi1-/- MEFs and Mxi1-/- mice, and the gene was regulated by Mxi1 in Mxi1 MEFs. Furthermore, proliferation pathways related to IGFBP-3 were regulated in Mxi1-/- mice compared to Mxi1+/+ mice. To determine the effect of Mxi1 inactivation on the induction of cell proliferation, a proliferation assay is performed in both Mxi1 MEFs and Mxi1 mice. Cell viability was regulated by Mxi1 in Mxi1 MEFs and number of PCNA-positive cells was increased in Mxi1-/- mice compared to Mxi1+/+ mice. Moreover, the IGFBP-3 level was decreased in proliferation defect regions in Mxi1-/- mice. The results support the suggestion that inactivation of Mxi1 has a positive effect on cell proliferation by down-regulating IGFBP-3.

  2. The relationship between maternal insulin-like growth factors 1 and 2 (IGF-1, IGF-2) and IGFBP-3 to gestational age and preterm delivery.

    LENUS (Irish Health Repository)

    Cooley, Sharon M

    2010-05-01

    To investigate the relationship between levels of insulin-like growth factors 1 and 2 (IGF-1, IGF-2), and insulin-like growth factor binding protein 3 (IGFBP-3) in antenatal maternal serum and gestational age at delivery.

  3. Protein Binding Pocket Dynamics.

    Science.gov (United States)

    Stank, Antonia; Kokh, Daria B; Fuller, Jonathan C; Wade, Rebecca C

    2016-05-17

    The dynamics of protein binding pockets are crucial for their interaction specificity. Structural flexibility allows proteins to adapt to their individual molecular binding partners and facilitates the binding process. This implies the necessity to consider protein internal motion in determining and predicting binding properties and in designing new binders. Although accounting for protein dynamics presents a challenge for computational approaches, it expands the structural and physicochemical space for compound design and thus offers the prospect of improved binding specificity and selectivity. A cavity on the surface or in the interior of a protein that possesses suitable properties for binding a ligand is usually referred to as a binding pocket. The set of amino acid residues around a binding pocket determines its physicochemical characteristics and, together with its shape and location in a protein, defines its functionality. Residues outside the binding site can also have a long-range effect on the properties of the binding pocket. Cavities with similar functionalities are often conserved across protein families. For example, enzyme active sites are usually concave surfaces that present amino acid residues in a suitable configuration for binding low molecular weight compounds. Macromolecular binding pockets, on the other hand, are located on the protein surface and are often shallower. The mobility of proteins allows the opening, closing, and adaptation of binding pockets to regulate binding processes and specific protein functionalities. For example, channels and tunnels can exist permanently or transiently to transport compounds to and from a binding site. The influence of protein flexibility on binding pockets can vary from small changes to an already existent pocket to the formation of a completely new pocket. Here, we review recent developments in computational methods to detect and define binding pockets and to study pocket dynamics. We introduce five

  4. Igf binding proteins protect undifferentiated spermatogonia in the zebrafish testis against excessive differentiation

    NARCIS (Netherlands)

    Safian, Diego; Morais, Roberto D; Bogerd, Jan; Schulz, Rüdiger W

    2016-01-01

    Insulin-like growth factor (Igf) binding proteins (Igfbps) modulate the availability of Igfs for their cognate receptors. In zebrafish testes, Igf3 promotes the proliferation and differentiation of type A undifferentiated (Aund) spermatogonia, and igf3 expression is strongly elevated by Fsh, but als

  5. Clinical significance of serum IGF-Ⅰ,IGF-Ⅱ and IGFBP-3 in liver cirrhosis

    Institute of Scientific and Technical Information of China (English)

    Yun-Lin Wu; Jing Ye; Shu Zhang; Jie Zhong; Rong-Ping Xi

    2004-01-01

    AIM: To investigate the relationship between insulin-likegrowth factor-Ⅰ, -Ⅱ (IGF-Ⅰ and IGF-Ⅱ), IGF-binding protein 3 (IGFBP-3) and Child-Pugh score in patients with liver cirrhosis, and to search for potential clinical markers of liver function. METHODS: Forty-four patients with advanced liver cirrhosis of viral origin were divided into 3 groups according to severity of cirrhosis (Child-Pugh score) and 38 healthy subjectsserved as controls. Serum levels of IGF-Ⅰ, IGF-Ⅱ and IGFBP3 were measured by immunoradiometric assay.RESULTS: Serum IGF-Ⅰ, IGF-Ⅱ and IGFBP-3 levels weresignificantly lower in patients with cirrhosis than in controls, and serum concentrations of IGF-Ⅰ, IGF-Ⅱ and IGFBP-3 were associated with the severity of liver dysfunction, and dropped sharply during the progression of liver failure. Among these 3 parameters, serum IGF-Ⅱ was the most sensitive and effective indicator for liver dysfunction. Concentrations of IGF-Ⅰ<30 ng/mL, IGF-Ⅱ<200 ng/mL and IGFBP-3 <6 ng/mL implied a negative prognosis for patients with liver cirrhosis. CONCLUSION: Serum IGF-Ⅰ, IGF-Ⅱ and IGFBP-3 may provide a new dimension in the assessment of liver dysfunction. Combined detection of serum IGF-Ⅰ, IGF-Ⅱ and IGFBP-3 with Child-Pugh score is more effective in predicting prognosis than Child-Pugh score alone.

  6. Advance on Insulin-like Growth Factor Binding Protein 2 in Lung Cancer and Other Solid Tumors

    Institute of Scientific and Technical Information of China (English)

    Wu Weiqin; Lu Kaihua

    2013-01-01

    Increasing evidence has revealed that IGF signalling plays a key role in cellular proliferation, survival, differentiation and senescence. Dysregulation of this signalling pathway is related to the development and progression of many human diseases, including cancer, diabetes and atherosclerosis. Insulin-like growth factor binding protein-2 (IGFBP-2) is reported to be a modulator of the action of insulin-like growth factors (IGFs), whereas IGF-independent effects of IGFBP-2 on cellular proliferation, apoptosis, and mobility have been revealed not only during the embryonic state but also in the pathological state of cancer. IGFBP-2 is involved in the genesis and progress of various malignancies including lung cancer. Recent ifndings show in many pre-clinical trials that IGFBP-2 may contribute to the transformation and progression of lung cancer. These studies suggest that IGFBP-2 may be a potential therapeutic target for lung cancer. In this review, we provide an overview on IGFBP-2, review corresponding studies investigating the role of IGFBP-2 as a cancer target in multiple tumors and discuss its possible mechanism in lung cancer.

  7. Long-term effects of insulin-like growth factor (IGF)-I on serum IGF-I, IGF-binding protein-3 and acid labile subunit in Laron syndrome patients with normal growth hormone binding protein.

    Science.gov (United States)

    Kanety, H; Silbergeld, A; Klinger, B; Karasik, A; Baxter, R C; Laron, Z

    1997-12-01

    A minority of patients with Laron syndrome have normal serum GH binding protein (GHBP), indicating that the defect is elsewhere than in the extracellular domain of the GH receptor. We have evaluated the effect of long-term IGF-I treatment on serum IGF-binding protein (IGFBP)-3 and the acid-labile subunit (ALS) in three sibling with Laron syndrome caused by a GH post-receptor defect and with normal GHBP. The children (a boy aged 3 years, a girl aged 4 years and a boy aged 10 years) were treated by daily s.c. injection of IGF-I in a dose of 150 micrograms/kg. IGFBP-3 was measured by RIA and Western ligand blotting, ALS by RIA. Based values of IGFBP-3 and ALS were low. During IGF-I treatment, the IGFBP-3 concentrations in the girl gradually increased, whereas in the boys there was a 60% decrease during the first week, followed by gradual increase towards baseline. The ALS concentrations followed a similar pattern. We conclude that IGF-I treatment induces and initial suppression and then an increase in the IGFBP-3 and ALS concentrations, confirming data from animal experiments that IGFBP-3 synthesis is not solely under GH control. The differences in responsiveness between the female and male siblings may reflect genetic differences, or lower circulating concentrations of IGF-I in the boys compared with the girl.

  8. TNFα inhibits IGFBP-3 through activation of p38α and casein kinase 2 in human retinal endothelial cells.

    Directory of Open Access Journals (Sweden)

    Qiuhua Zhang

    Full Text Available We recently reported a reciprocal relationship between tumor necrosis factor alpha (TNFα and insulin-like receptor growth factor binding protein 3 (IGFBP-3 in whole retina of normal and IGFBP-3 knockout mice. A similar relationship was also observed in cultured retinal endothelial cells (REC. We found that TNFα significantly reduced IGFBP-3 levels and vice-versa, IGFBP-3 can lower TNFα and TNFα receptor expression. Since IGFBP-3 is protective to the diabetic retina and TNFα is causative in the development of diabetic retinopathy, we wanted to better understand the cellular mechanisms by which TNFα can reduce IGFBP-3 levels. For these studies, primary human retinal endothelial cells (REC were used since these cells undergo TNFα-mediated apoptosis under conditions of high glucose conditions and contribute to diabetic retinopathy. We first cultured REC in normal or high glucose, treated with exogenous TNFα, then measured changes in potential signaling pathways, with a focus on P38 mitogen-activated protein kinase alpha (P38α and casein kinase 2 (CK2 as these pathways have been linked to both TNFα and IGFBP-3. We found that TNFα significantly increased phosphorylation of P38α and CK2. Furthermore, specific inhibitors of P38α or CK2 blocked TNFα inhibition of IGFBP-3 expression, demonstrating that TNFα reduces IGFBP-3 through activation of P38α and CK2. Since TNFα and IGFBP-3 are key mediators of retinal damage and protection respectively in diabetic retinopathy, increased understanding of the relationship between these two proteins will offer new therapeutic options for treatment.

  9. Insulin-like growth factor-binding protein-1: serum levels, promoter polymorphism, and associations with components of the metabolic syndrome in short subjects born small for gestational age.

    Science.gov (United States)

    van der Kaay, Daniëlle; Deal, Cheri; de Kort, Sandra; Willemsen, Ruben; Leunissen, Ralph; Ester, Wietske; Paquette, Jean; van Doorn, Jaap; Hokken-Koelega, Anita

    2009-04-01

    IGF binding protein (IGFBP)-1 is the only acute regulator of IGF-I bioavailability. Its production is suppressed by insulin, and low levels are associated with hyperinsulinemia and cardiovascular disease risk in adults. Data on IGFBP-1 levels in short, small for gestational age (SGA) subjects are scarce, and associations with IGFBP1 promoter single nucleotide polymorphisms have not been established. The aim of the study was to determine IGFBP-1 levels in short SGA subjects compared with those in controls, to assess genotype frequency of the -575 G/A single nucleotide polymorphism, and to determine its impact on IGFBP-1 levels. A total of 272 short subjects born SGA and 330 subjects with normal stature (245 children, 85 young adults) participated in the study. We measured fasting levels of IGFBP-1, IGF-I, insulin and lipid parameters, and body composition. IGFBP-1 sd score (SDS) was comparable to controls in lean, short, SGA children but significantly lower in short SGA adults with normal fat mass (P < 0.001). IGFBP-1 SDS correlated significantly with insulin levels, systolic blood pressure SDS, and various lipid parameters. Baseline IGFBP-1 SDS was lowest in SGA children with -575 GG genotype and significantly higher in SGA children with one or two copies of the A allele. In response to a given insulin level, children with the AA genotype had a significantly higher IGFBP-1 SDS compared to children with the GG genotype. Normal IGFBP-1 levels in lean, short, SGA children may reflect a normal metabolic state, despite reported hyperinsulinemia. IGFBP-1 is modulated by polymorphic variability and seems to be an additional player in the complex interaction between the IGF-IGFBP axis, glucose homeostasis, and lipid metabolism.

  10. IGF-II and IGFBP-6 regulate cellular contractility and proliferation in Dupuytren's disease.

    Science.gov (United States)

    Raykha, Christina; Crawford, Justin; Gan, Bing Siang; Fu, Ping; Bach, Leon A; O'Gorman, David B

    2013-10-01

    Dupuytren's disease (DD) is a common and heritable fibrosis of the palmar fascia that typically manifests as permanent finger contractures. The molecular interactions that induce the development of hyper-contractile fibroblasts, or myofibroblasts, in DD are poorly understood. We have identified IGF2 and IGFBP6, encoding insulin-like growth factor (IGF)-II and IGF binding protein (IGFBP)-6 respectively, as reciprocally dysregulated genes and proteins in primary cells derived from contracture tissues (DD cells). Recombinant IGFBP-6 inhibited the proliferation of DD cells, patient-matched control (PF) cells and normal palmar fascia (CT) cells. Co-treatments with IGF-II, a high affinity IGFBP-6 ligand, were unable to rescue these effects. A non-IGF-II binding analog of IGFBP-6 also inhibited cellular proliferation, implicating IGF-II-independent roles for IGFBP-6 in this process. IGF-II enhanced the proliferation of CT cells, but not DD or PF cells, and significantly enhanced DD and PF cell contractility in stressed collagen lattices. While IGFBP-6 treatment did not affect cellular contractility, it abrogated the IGF-II-induced contractility of DD and PF cells in stressed collagen lattices. IGF-II also significantly increased the contraction of DD cells in relaxed lattices, however this effect was not evident in relaxed collagen lattices containing PF cells. The disparate effects of IGF-II on DD and PF cells in relaxed and stressed contraction models suggest that IGF-II can enhance lattice contractility through more than one mechanism. This is the first report to implicate IGFBP-6 as a suppressor of cellular proliferation and IGF-II as an inducer of cellular contractility in this connective tissue disease.

  11. The associations of diet with serum insulin-like growth factor I and its main binding proteins in 292 women meat-eaters, vegetarians, and vegans.

    Science.gov (United States)

    Allen, Naomi E; Appleby, Paul N; Davey, Gwyneth K; Kaaks, Rudolf; Rinaldi, Sabina; Key, Timothy J

    2002-11-01

    The lower rates of some cancers in Asian countries than in Western countries may be partly because of diet, although the mechanisms are unknown. The aim of this cross-sectional study was to determine whether a plant-based (vegan) diet is associated with a lower circulating level of insulin-like growth factor I (IGF-I) compared with a meat-eating or lacto-ovo-vegetarian diet among 292 British women, ages 20-70 years. The mean serum IGF-I concentration was 13% lower in 92 vegan women compared with 99 meat-eaters and 101 vegetarians (P = 0.0006). The mean concentrations of both serum IGF-binding protein (IGFBP)-1 and IGFBP-2 were 20-40% higher in vegan women compared with meat-eaters and vegetarians (P = 0.005 and P = 0.0008 for IGFBP-1 and IGFBP-2, respectively). There were no significant differences in IGFBP-3, C-peptide, or sex hormone-binding globulin concentrations between the diet groups. Intake of protein rich in essential amino acids was positively associated with serum IGF-I (Pearson partial correlation coefficient; r = 0.27; P diet groups. These data suggest that a plant-based diet is associated with lower circulating levels of total IGF-I and higher levels of IGFBP-1 and IGFBP-2.

  12. Development and clinical evaluation of a novel immunoassay for the binary complex of IGF-I and IGF-binding protein-1 in human serum

    DEFF Research Database (Denmark)

    Frystyk, Jan; Højlund, Kurt; Rasmussen, Kirsten Nyborg

    2002-01-01

    Correlation studies have suggested that IGF-binding protein (IGFBP)-1 is a dynamic regulator of free IGF-I. To further study this, we developed a monoclonal immunofluorometric assay specific for the binary complex of IGF-I and IGFBP-1 in human serum. An IGFBP-1 antibody, which recognizes all...... healthy subjects were fasted for 72 h. Samples were collected every 3 h. During fasting, free IGF-I was reduced by two thirds (P positively in all subjects (0.89 ...), because these patients show profound alterations in their IGF-system. In both groups, the binary complex was increased about 2.5-fold (P

  13. Protection of blood retinal barrier and systemic vasculature by insulin-like growth factor binding protein-3.

    Directory of Open Access Journals (Sweden)

    Yagna P R Jarajapu

    Full Text Available Previously, we showed that insulin growth factor (IGF-1 binding protein-3 (IGFBP-3, independent of IGF-1, reduces pathological angiogenesis in a mouse model of the oxygen-induced retinopathy (OIR. The current study evaluates novel endothelium-dependent functions of IGFBP-3 including blood retinal barrier (BRB integrity and vasorelaxation. To evaluate vascular barrier function, either plasmid expressing IGFBP-3 under the regulation of an endothelial-specific promoter or a control plasmid was injected into the vitreous humor of mouse pups (P1 and compared to the non-injected eyes of the same pups undergoing standard OIR protocol. Prior to sacrifice, the mice were given an injection of horseradish peroxidase (HRP. IGFBP-3 plasmid-injected eyes displayed near-normal vessel morphology and enhanced vascular barrier function. Further, in vitro IGFBP-3 protects retinal endothelial cells from VEGF-induced loss of junctional integrity by antagonizing the dissociation of the junctional complexes. To assess the vasodilatory effects of IGFBP-3, rat posterior cerebral arteries were examined in vitro. Intraluminal IGFBP-3 decreased both pressure- and serotonin-induced constrictions by stimulating nitric oxide (NO release that were blocked by L-NAME or scavenger receptor-B1 neutralizing antibody (SRB1-Ab. Both wild-type and IGF-1-nonbinding mutant IGFBP-3 (IGFBP-3NB stimulated eNOS activity/NO release to a similar extent in human microvascular endothelial cells (HMVECs. NO release was neither associated with an increase in intracellular calcium nor decreased by Ca(2+/calmodulin-dependent protein kinase II (CamKII blockade; however, dephosphorylation of eNOS-Thr(495 was observed. Phosphatidylinositol 3-kinase (PI3K activity and Akt-Ser(473 phosphorylation were both increased by IGFBP-3 and selectively blocked by the SRB1-Ab or PI3K blocker LY294002. In conclusion, IGFBP-3 mediates protective effects on BRB integrity and mediates robust NO release to stimulate

  14. Insulin-like growth factor-binding protein-2 promotes prostate cancer cell growth via IGF-dependent or -independent mechanisms and reduces the efficacy of docetaxel

    Science.gov (United States)

    Uzoh, C C; Holly, J M P; Biernacka, K M; Persad, R A; Bahl, A; Gillatt, D; Perks, C M

    2011-01-01

    Background: The development of androgen independence, chemo-, and radioresistance are critical markers of prostate cancer progression and the predominant reasons for its high mortality. Understanding the resistance to therapy could aid the development of more effective treatments. Aim: The aim of this study is to investigate the effects of insulin-like growth factor-binding protein-2 (IGFBP-2) on prostate cancer cell proliferation and its effects on the response to docetaxel. Methods: DU145 and PC3 cells were treated with IGFBP-2, insulin-like growth factor I (IGF-I) alone or in combination with blockade of the IGF-I receptor or integrin receptors. Cells were also treated with IGFBP-2 short interfering ribonucleic acid with or without a PTEN (phosphatase and tensin homologue deleted on chromosome 10) inhibitor or docetaxel. Tritiated thymidine incorporation was used to measure cell proliferation and Trypan blue cell counting for cell death. Levels of IGFBP-2 mRNA were measured using RT–PCR. Abundance and phosphorylation of proteins were assessed using western immunoblotting. Results: The IGFBP-2 promoted cell growth in both cell lines but with PC3 cells this was in an IGF-dependent manner, whereas with DU145 cells the effect was independent of IGF receptor activation. This IGF-independent effect of IGFBP-2 was mediated by interaction with β-1-containing integrins and a consequent increase in PTEN phosphorylation. We also determined that silencing IGFBP-2 in both cell lines increased the sensitivity of the cells to docetaxel. Conclusion: The IGFBP-2 has a key role in the growth of prostate cancer cells, and silencing IGFBP-2 expression reduced the resistance of these cells to docetaxel. Targeting IGFBP-2 may increase the efficacy of docetaxel. PMID:21487405

  15. Role of IGFBP2, IGF-I and IGF-II in regulating long bone growth.

    Science.gov (United States)

    Fisher, Melanie C; Meyer, Carissa; Garber, Graham; Dealy, Caroline N

    2005-12-01

    The IGF axis is important for long bone development, homeostasis and disease. The activities of IGF-I and IGF-II are regulated by IGF binding proteins (IGFBPs). IGF-I and IGFBP2 are co-expressed in dynamic fashions in the developing long bones of the chick wing, and we have found that IGF-II is present in the cartilage model and surrounding perichondrium, proliferative and hypertrophic chondrocytes and developing periosteum. To gain insight into endogenous roles of IGF-I, IGF-II and IGFBP2 in long bone development, we have overexpressed IGFBP2 in the developing skeletal elements of the embryonic chick wing in vivo, using an RCAS retroviral vector. IGFBP2 overexpression led to an obvious shortening of the long bones of the wing. We have investigated, at the cellular and molecular levels, the mechanism of action whereby IGFBP2 overexpression impairs long bone development in vivo. At an early stage, IGFBP2 excess dramatically inhibits proliferation by the chondrocytes of the cartilage models that prefigure the developing long bones. Later, IGFBP2 excess also reduces proliferation of the maturing chondrocytes and attenuates proliferation by the perichondrium/developing periosteum. IGFBP2 excess does not affect morphological or molecular indicators of chondrocyte maturation, osteoblast differentiation or cell/matrix turnover, such as expression of Ihh, PTHrP, type X collagen and osteopontin, or distribution and relative abundance of putative clast cells. We also have found that IGFBP2 blocks the ability of IGF-I and IGF-II to promote proliferation and matrix synthesis by wing chondrocytes in vitro. Together, our results suggest that the mechanism of action whereby IGFBP2 excess impairs long bone development is to inhibit IGF-mediated proliferation and matrix synthesis by the cartilage model; reduce the proliferation and progression to hypertrophy by the maturing chondrocytes; and attenuate proliferation and formation of the periosteal bony collar. These actions retard

  16. Analysis of APC and IGFBP7 promoter gene methylation in Swedish and Vietnamese colorectal cancer patients.

    Science.gov (United States)

    Dimberg, Jan; Hong, Thai Trinh; Skarstedt, Marita; Löfgren, Sture; Zar, Niklas; Matussek, Andreas

    2013-01-01

    The tumour suppressor gene adenomatous polyposis coli (APC) is a key component that drives colorectal carcinogenesis. The reported DNA methylation in the promoter of APC varies greatly among studies of colorectal cancer (CRC) in different populations. Insulin-like growth factor binding protein 7 (IGFBP7), also known as IGFBP-related protein 1 (IGFBP-rP1), is expressed in various tissue types, including the lung, brain, prostate and gastrointestinal tract, and has been suggested to play a tumour suppressor role against colorectal carcinogenesis. Studies have indicated that IGFBP7 is inactivated by DNA methylation in human colon, lung and breast cancer. In the present study, we used the methylation-specific polymerase chain reaction to study the methylation status of the APC and IGFBP7 gene promoters in cancerous and paired normal tissue to evaluate its impact on clinical factors and association with ethnicity, represented by Swedish and Vietnamese CRC patients. We also investigated the distribution of CpG islands and the CpG dinucleotide density of each CpG island in the regions which were the subject of our investigation. Overall, normal tissue from Swedish patients exhibited a significantly higher frequency of IGFBP7 gene methylation in comparison with that of Vietnamese patients. Moreover, a significantly higher number of cancer tissues from Vietnamese individuals showed higher levels of methylation versus the paired normal tissue compared with that of Swedish patients. When we studied the methylation in cancer compared with the matched normal tissue in individuals, we found that a significantly higher number of Vietnamese patients had a higher degree of IGFBP7 gene methylation in cancer versus matched normal tissue in comparison with Swedish patients. Taken together, our results suggest that the methylation of the APC and IGFBP7 gene promoter region in cancerous tissue, in combination with the predominance of methylation in normal tissue, may serve as a

  17. Promoter-dependent and -independent activation of insulin-like growth factor binding protein-5 gene expression by prostaglandin E2 in primary rat osteoblasts

    Science.gov (United States)

    McCarthy, T. L.; Casinghino, S.; Mittanck, D. W.; Ji, C. H.; Centrella, M.; Rotwein, P.

    1996-01-01

    Insulin-like growth factor (IGF) action is mediated by high affinity cell surface IGF receptors and modulated by a family of secreted IGF binding proteins (IGFBPs). IGFBP-5, the most conserved of six IGFBPs characterized to date, uniquely potentiates the anabolic actions of IGF-I for skeletal cells. In osteoblasts, IGFBP-5 production is stimulated by prostaglandin E2 (PGE2), a local factor that mediates certain effects induced by parathyroid hormone, cytokines such as interleukin-1 and transforming growth factor-beta, and mechanical strain. In this study, we show that transcriptional and post-transcriptional events initiated by PGE2 collaborate to enhance IGFBP-5 gene expression in primary fetal rat osteoblast cultures. PGE2 treatment stimulated up to a 7-fold rise in steady-state levels of IGFBP-5 mRNA throughout 32 h of incubation. Analysis of nascent IGFBP-5 mRNA suggested that PGE2 had only a modest stimulatory effect on IGFBP-5 gene transcription, and transient transfection studies with IGFBP-5 promoter-reporter genes confirmed that PGE2 enhanced promoter activity by approximately 2-fold. Similar stimulatory effects were seen with forskolin. A DNA fragment with only 51 base pairs of the 5'-flanking sequence retained hormonal responsiveness, which may be mediated by a binding site for transcription factor AP-2 located at positions -44 to -36 in the proximal IGFBP-5 promoter. Incubation of osteoblasts with the mRNA transcriptional inhibitor 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole demonstrated that PGE2 enhanced IGFBP-5 mRNA stability by 2-fold, increasing the t1/2 from 9 to 18 h. The effects of PGE2 on steady-state IGFBP-5 transcripts were abrogated by preincubating cells with cycloheximide, indicating that the effects of PGE2 on both gene transcription and mRNA stability required ongoing protein synthesis. Therefore, both promoter-dependent and -independent pathways converge to enhance IGFBP-5 gene expression in response to PGE2 in osteoblasts.

  18. Prognostic usefulness of insulin-like growth factor-binding protein 7 in heart failure with reduced ejection fraction: a novel biomarker of myocardial diastolic function?

    Science.gov (United States)

    Gandhi, Parul U; Gaggin, Hanna K; Sheftel, Alex D; Belcher, Arianna M; Weiner, Rory B; Baggish, Aaron L; Motiwala, Shweta R; Liu, Peter P; Januzzi, James L

    2014-11-15

    Insulin-like growth factor-binding protein 7 (IGFBP7) is a biomarker that has recently been associated with heart failure and cardiac hypertrophy. The aim of this study was to examine IGFBP7 relative to echocardiographic abnormalities reflecting diastolic dysfunction. One hundred twenty-four patients with ambulatory heart failure with reduced ejection fraction and baseline detailed 2-dimensional echocardiograms were followed for a mean of 10 months. IGFBP7 was measured serially at each office visit; 108 patients underwent follow-up echocardiography. Echocardiographic parameters of diastolic function were compared at baseline and over time. IGFBP7 concentrations were not linked to left ventricular size or systolic function. In contrast, those with elevated baseline IGFBP7 concentrations were more likely to have abnormalities of parameters describing diastolic function, such as higher left atrial volume index, transmitral E/A ratio, E/E' ratio, and right ventricular systolic pressure. IGFBP7 was correlated with left atrial volume index (ρ = 0.237, p = 0.008), transmitral E/A ratio (ρ = 0.304, p = 0.001), E/E' ratio (ρ = 0.257, p = 0.005), and right ventricular systolic pressure (ρ = 0.316, p = 0.001). Furthermore, each was found to be independently predictive of IGFBP7 in adjusted analysis. In subjects with baseline and final echocardiograms, more time spent with elevated IGFBP7 concentrations in serial measurement was associated with worsening diastolic function and increasing left atrial volume index or right ventricular systolic pressure. IGFBP7 concentrations were predictive of an increased risk for cardiovascular events independent of echocardiographic measures of diastolic function (p = 0.006). In conclusion, IGFBP7 is a novel prognostic biomarker for heart failure with reduced ejection fraction and shows significant links to the presence and severity of echocardiographic parameters of abnormal diastolic function.

  19. Potentiation of growth factor signaling by insulin-like growth factor-binding protein-3 in breast epithelial cells requires sphingosine kinase activity.

    Science.gov (United States)

    Martin, Janet L; Lin, Mike Z; McGowan, Eileen M; Baxter, Robert C

    2009-09-18

    We have investigated the mechanism underlying potentiation of epidermal growth factor receptor (EGFR) and type 1 insulin-like growth factor receptor (IGFR1) signaling by IGF-binding protein-3 (IGFBP-3) in MCF-10A breast epithelial cells, focusing on a possible involvement of the sphingosine kinase (SphK) system. IGFBP-3 potentiated EGF-stimulated EGF receptor activation and DNA synthesis, and this was blocked by inhibitors of SphK activity or small interference RNA-mediated silencing of SphK1, but not SphK2, expression. Similarly, IGFR1 phosphorylation and DNA synthesis stimulated by LR3-IGF-I (an IGF-I analog not bound by IGFBP-3), were enhanced by IGFBP-3, and this was blocked by SphK1 silencing. SphK1 expression and activity were stimulated by IGFBP-3 approximately 2-fold over 24 h. Silencing of sphingosine 1-phosphate receptor 1 (S1P1) or S1P3, but not S1P2, abolished the effect of IGFBP-3 on EGF-stimulated EGFR activation. The effects of IGFBP-3 could be reproduced with exogenous S1P or medium conditioned by cells treated with IGFBP-3, and this was also blocked by inhibition of S1P1 and S1P3. These data indicate that potentiation of growth factor signaling by IGFBP-3 in MCF-10A cells requires SphK1 activity and S1P1/S1P3, suggesting that S1P, the product of SphK activity and ligand for S1P1 and S1P3, is the "missing link" mediating IGF and EGFR transactivation and cell growth stimulation by IGFBP-3.

  20. Genomewide meta-analysis identifies loci associated with IGF-I and IGFBP-3 levels with impact on age-related traits

    DEFF Research Database (Denmark)

    Teumer, Alexander; Qi, Qibin; Nethander, Maria

    2016-01-01

    The growth hormone/insulin-like growth factor (IGF) axis can be manipulated in animal models to promote longevity, and IGF-related proteins including IGF-I and IGF-binding protein-3 (IGFBP-3) have also been implicated in risk of human diseases including cardiovascular diseases, diabetes, and cancer...... IGFBP3 and genes within the NUBP2 locus (IGFALS and HAGH) may affect circulating IGF-I and IGFBP-3 concentrations. The IGF-I-decreasing allele of SNP rs934073, which is an eQTL of ASXL2, was associated with lower adiposity and higher likelihood of survival beyond 90 years. The known longevity...

  1. Insulin-Like Growth Factor Binding Protein-6 Alters Skeletal Muscle Differentiation of Human Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Doaa Aboalola

    2017-01-01

    Full Text Available Insulin-like growth factor binding protein-6 (IGFBP-6, the main regulator of insulin-like growth factor-2 (IGF-2, is a component of the stem cell niche in developing muscle cells. However, its role in muscle development has not been clearly defined. In this study, we investigated the role of IGFBP-6 in muscle commitment and differentiation of human mesenchymal stem cells derived from the placenta. We showed that placental mesenchymal stem cells (PMSCs have the ability to differentiate into muscle cells when exposed to a specific culture medium by expressing muscle markers Pax3/7, MyoD, myogenin, and myosin heavy chain in a stage-dependent manner with the ultimate formation of multinucleated fibers and losing pluripotency-associated markers, OCT4 and SOX2. The addition of IGFBP-6 significantly increased pluripotency-associated markers as well as muscle differentiation markers at earlier time points, but the latter decreased with time. On the other hand, silencing IGFBP-6 decreased both pluripotent and differentiation markers at early time points. The levels of these markers increased as IGFBP-6 levels were restored. These findings indicate that IGFBP-6 influences MSC pluripotency and myogenic differentiation, with more prominent effects observed at the beginning of the differentiation process before muscle commitment.

  2. DIAGNOSTIC VALUE OF SERUM INSULIN-LIKE GROWTH FACTOR BINDING PROTEIN-3 IN CHILDREN WITH OR WITHOUT GROWTH HORMONE DEFICIENCY

    Institute of Scientific and Technical Information of China (English)

    覃舒文; 史轶蘩; 邓洁英

    2002-01-01

    Objective. To study the value of serum insulin-like growth factor binding protein-3 (IGFBP-3) levels in differential diagnosis of growth hormone deficiency (GHD). Methods. To measure serum IGFBP-3 levels by RIA in normal children and adolescents, GHD children and short-stature children without GHD. Results. Serum level of IGFBP-3 in 129 children with untreated GHD and with no pubertal development was 1.6± 0.9 mg/L, which was less than that in normal group of the same age, but overlapped with the normal children in Tanner stage I. After six -month treatment with recombinant human growth hormone (rhGH), serum level of IGFBP-3 in 59 GHD significantly increased from 1.3± 0.7 mg/L to 2.7± 0.9 mg/L, accompanied by an increase of body heights, growth velocities and serum level of IGF-1. Serum level of IGFBP-3 in 55 short-stature children without GHD was 3.3± 2.2 mg/L, which was not significantly different from that in normal group. Conclusion. Serum IGFBP-3 level can reflect the status of GH secretion in children with GHD and is a useful marker for differential diagnosis of GHD.

  3. Demethylation of IGFBP5 by Histone Demethylase KDM6B Promotes Mesenchymal Stem Cell-Mediated Periodontal Tissue Regeneration by Enhancing Osteogenic Differentiation and Anti-Inflammation Potentials.

    Science.gov (United States)

    Liu, Dayong; Wang, Yuejun; Jia, Zhi; Wang, Liping; Wang, Jinsong; Yang, Dongmei; Song, Jianqiu; Wang, Songlin; Fan, Zhipeng

    2015-08-01

    Mesenchymal stem cell (MSC)-mediated periodontal tissue regeneration is considered a promising method for periodontitis treatment. The molecular mechanism underlying directed differentiation and anti-inflammatory actions remains unclear, thus limiting potential MSC application. We previously found that insulin-like growth factor binding protein 5 (IGFBP5) is highly expressed in dental tissue-derived MSCs compared with in non-dental tissue-derived MSCs. IGFBP5 is mainly involved in regulating biological activity of insulin-like growth factors, and its functions in human MSCs and tissue regeneration are unclear. In this study, we performed gain- and loss-of-function assays to test whether IGFBP5 could regulate the osteogenic differentiation and anti-inflammatory potential in MSCs. We found that IGFBP5 expression was upregulated upon osteogenic induction, and that IGFBP5 enhanced osteogenic differentiation in MSCs. We further showed that IGFBP5 prompted the anti-inflammation effect of MSCs via negative regulation of NFκB signaling. Depletion of the histone demethylase lysine (K)-specific demethylase 6B (KDM6B) downregulated IGFBP5 expression by increasing histone K27 methylation in the IGFBP5 promoter. Moreover, IGFBP5 expression in periodontal tissues was downregulated in individuals with periodontitis compared with in healthy people, and IGFBP5 enhanced MSC-mediated periodontal tissue regeneration and alleviated local inflammation in a swine model of periodontitis. In conclusion, our present results reveal a new function for IGFBP5, provide insight into the mechanism underlying the directed differentiation and anti-inflammation capacities of MSCs, and identify a potential target mediator for improving tissue regeneration.

  4. Cellulose binding domain proteins

    Science.gov (United States)

    Shoseyov, Oded; Shpiegl, Itai; Goldstein, Marc; Doi, Roy

    1998-01-01

    A cellulose binding domain (CBD) having a high affinity for crystalline cellulose and chitin is disclosed, along with methods for the molecular cloning and recombinant production thereof. Fusion products comprising the CBD and a second protein are likewise described. A wide range of applications are contemplated for both the CBD and the fusion products, including drug delivery, affinity separations, and diagnostic techniques.

  5. Insulin-like growth factor binding protein-1 activates integrin-mediated intracellular signaling and migration in oligodendrocytes

    NARCIS (Netherlands)

    Chesik, Daniel; De Keyser, Jacques; Bron, Reinier; Fuhler, Gwenny M.

    2010-01-01

    P>In multiple sclerosis (MS), oligodendrocytes in lesions are lost, leaving damaged tissue virtually devoid of these myelin-producing cells. Our group has recently demonstrated enhanced expression of insulin-like growth factor (IGF) binding protein-1 (IGFBP-1) in oligodendrocytes (CNPase+) localized

  6. Acromegaly: the significance of serum total and free IGF-I and IGF-binding protein-3 in diagnosis

    NARCIS (Netherlands)

    A-J. van der Lely (Aart-Jan); W.W. de Herder (Wouter); J.A.M.J.L. Janssen (Joop); S.W.J. Lamberts (Steven)

    1997-01-01

    textabstractWe have studied the physiological and clinical relevance of measurements of serum total and free IGF-I and IGF-binding protein-3 (IGFBP-3) in 57 previously untreated patients with active acromegaly (32 males, 25 females; mean age 47 years) as compared with sex- and age-

  7. Analysis the relationship between growth response and IGF -1、IGFBP-3、IGF-1/IGFBP-3 during growth hormone treatment in GHD children%生长激素缺乏症儿童rhGH治疗效果与IGF-1、IGFBP-3、IGF-1/IGFBP-3关系的研究

    Institute of Scientific and Technical Information of China (English)

    李琼艳; 高宗燕; 蓝丹; 蓝秋慧; 许田田; 李琳迪; 李新叶

    2014-01-01

    Objective :To explore the relationship between growth response and the changes in insulin -like growth factor 1 (IGF -1) ,insulin -like growth factor binding protein 3 (IGFBP -3) and the IGF -I/IGFBP -3 molar ratio during recombinant human growth hormone (rhGH) treat-ment in growth hormone deficiency (GHD) children .Methods :The study includes 44 GHD children diagnosed in the first affiliated Hospital of Guangxi Medical University from January 2011 to February 2014 and treated with rhGH .Serum IGF -1 ,IGFBP -3 were measured before treatment and after 3 months ,6 months of treatment respectively .IGF -I ,IGFBP -3 and IGF -I/IGFBP -3 were expressed as SD scores using reference values from the normal population .Analysis the changes of IGF -1SDS ,IGFBP -3SDS ,IGF -1/IGFBP -3SDS after 3 months ,6 months of treatment and their cor-relation with growth velocity .Results:(1) After 3 months ,IGF -1SDS were significantly higher than pretreatment while IGFBP -3SDS ,IGF -1/IG-FBP -3SDS without obvious difference ;(2)Compared to pretreatment ,IGF -1SDS ,IGF -1/IGFBP -3SDS measured after 6 month were significant-ly higher ,while IGFBP -3SDS has no statistical difference ;(3)Baseline IGF -1SDS ,IGFBP -3SDS ,IGF -1/IGFBP -3SDS and GV in the first 3 months had no significantly relation ;the GV in 6 month is negatively correlated with baseline IGF -1SDS and positively correlated with the changing of IGF -1SDS significantly .;After 6 months ,the GV had no relationship with baseline IGFBP -3SDS ,IGF -1/IGFBP -3SDS and IGF -1SDS ,IG-FBP -3SDS ,IGF -1/IGFBP -3SDS measured at 6 month later .Conclusion:IGF -1 may help predict the efficacy of rhGH treatment in GHD chil-dren .%目的:本文旨在分析生长激素缺乏症患儿应用重组人生长激素治疗后血清胰岛素样生长因子-1(IGF -1)、胰岛素样生长因子结合蛋白3(IGFBP -3)以及两者比值(IGF -1/IGFBP -3)三项指标的变化情况及探讨其在疗效评估中的价值。方法:选择2011

  8. Synergistic effects of 1,25-Dihydroxyvitamin D3 and TGF-beta1 on the production of insulin-like growth factor binding protein 3 in human bone marrow stromal cell cultures

    DEFF Research Database (Denmark)

    Kveiborg, Marie; Flyvbjerg, Allan; Kassem, M

    2002-01-01

    1,25-Dihydroxyvitamin D3 (calcitriol), transforming growth factor-beta (TGF-beta), and insulin-like growth factors (IGFs) are all important bone regulatory factors known to affect proliferation and differentiation of human bone-forming cells (osteoblasts). We have previously shown that TGF-beta1...... increased IGF-I and IGF-binding protein (IGFBP)-3 production in human bone marrow stromal (hMS) osteoblast progenitors and calcitriol stimulated IGFBP-3 and IGFBP-4 production. As interaction between signaling pathways of these factors has been reported, the present study aimed at examining the concerted...... actions on components of the IGF-system. We report that co-treatment with TGF-beta1 and calcitriol resulted in a synergistic increase in IGFBP-3 production, thereby suggesting that the effects of these factors on hMS osteoblast differentiation may involve the observed increase in IGFBP-3....

  9. Inhibition of Breast Cancer Growth by IGFBP-3

    Science.gov (United States)

    1998-10-01

    interacting proteins including putative IGFBP-3 receptor in human breast cancer cells by employing the yeast two-hybrid system. Two cDNA clones matched sequences in the GenBank database: (1) Eps8 - epidermal growth factor receptor kinase substrate, and (2) GRP78/BiP - glucose regulated stress protein, or human immunoglobulin heavy chain binding protein. The third cDNA, designated clone 4-33, was not identified in the database and represents a novel gene / protein. I have thus far concentrated my efforts on this novel cDNA clone: (1) synthesis of recombinant human

  10. IGFBP3 Promoter Methylation in Colorectal Cancer: Relationship with Microsatellite Instability, CpG Island Methylator Phenotype, p53

    Directory of Open Access Journals (Sweden)

    Takako Kawasaki

    2007-12-01

    Full Text Available Insulin-like growth factor binding protein 3 (IGFBP3, which is induced by wild-type p53, regulates IGF and interacts with the TGF-β pathway. IGFBP3 promoter methylation may occur in colorectal cancer with or without the CpG island methylator phenotype (CIMP, which is associated with microsatellite instability (MSI and TGFBR2 mutation. We examined the relationship between IGFBP3 methylation, p53 expression, CIMP and MSI in 902 population-based colorectal cancers. Utilizing real-time PCR (MethyLight, we quantified promoter methylation in IGFBP3 and eight other CIMP-high-specific promoters (CACNA1G, CDKN2A, CRABP1, IGF2, MLH1, NEUROG1, RUNX3, and SOCS1. IGFBP3 methylation was far more frequent in non-MSI-high CIMP-high tumors (85% = 35/41 than in MSI-high CIMPhigh (49% = 44/90, P < .0001, MSI-high non-CIMP-high (17% = 6/36, P < .0001, non-MSI-high non-CIMP-high tumors (22% = 152/680, P < .0001. Among CIMPhigh tumors, the inverse relationship between MSI and IGFBP3 methylation persisted in p53-negative tumors (P < .0001, but not in p53-positive tumors. IGFBP3 methylation was associated inversely with TGFBR2 mutation in MSI-high non-CIMP-high tumors (P = .02. In conclusion, IGFBP3 methylation is inversely associated with MSI in CIMP-high colorectal cancers, this relationship is limited to p53-negative tumors. Our data suggest complex relationship between global genomic/epigenomic phenomena (such as MSI/ CIMP, single molecular events (e.g., IGFBP3 methylation, TP53 mutation, TGFBR2 mutation, the related pathways.

  11. Effect of hyperthyroidism on circulating levels of free and total IGF-I and IGFBPs in rats.

    Science.gov (United States)

    Frystyk, J; Grønbaek, H; Skjaerbaek, C; Flyvbjerg, A

    1995-11-01

    Thyroid hormones are suggested to have a permissive role in growth hormone (GH) and insulin-like growth factor I (IGF-I) action and a specific effect on plasma levels of some of the GH-independent IGF binding proteins (IGFBPs). We have investigated the effect of thyroxine (T4) administration on circulating levels of free and total (extractable) IGF-I and IGFBPs in 8-wk-old rats treated with 0, 200, 400, and 600 micrograms/kg T4, respectively. Serum free IGF-I was determined by an ultrafiltration method, serum total IGF-I after acid-ethanol extraction, and serum IGFBPs using Western ligand blotting, which yielded four distinct molecular bands: two single bands at 24 and 30 kDa and a double band at 38 and 42 kDa (38-42 kDa). After 13 days of hyperthyroidism, serum total IGF-I and the high-molecular 38-42 kDa IGFBP were unchanged, whereas the 24-kDa IGFBP and 30-kDa IGFBP increased significantly (P < 0.05). Serum free IGF-I was significantly (P < 0.05) decreased in animals treated with 400 and 600 micrograms/kg T4. In addition, free IGF-I correlated inversely (P < 0.005) with the 24-kDa IGFBP, 30-kDa IGFBP, and serum total triiodothyronine. We conclude that hyperthyroidism in rats increases the circulating low-molecular IGFBPs and induces a reduction in free IGF-I. This may provide an important regulation of IGF bioactivity by thyroid hormones.

  12. Genetic and epigenetic variability in the gene for IGFBP-3 (IGFBP3): correlation with serum IGFBP-3 levels and growth in short children born small for gestational age.

    Science.gov (United States)

    van der Kaay, D C M; Hendriks, A E J; Ester, W A; Leunissen, R W J; Willemsen, R H; de Kort, S W K; Paquette, J R; Hokken-Koelega, A C S; Deal, C L

    2009-06-01

    IGF-I and IGFBP-3 play a central role in fetal and postnatal growth and levels are low in short SGA children. The -202 A/C and -185 C/T SNPs are located near elements involved in directing IGFBP3 promoter activity and expression. Changes in promoter CpG methylation status affect transcription factor binding and transcriptional activation of IGFBP3 in vitro. To assess the relationship between IGFBP3 promoter SNPs, IGFBP-3 levels, spontaneous growth and growth response to GH treatment in short prepubertal SGA children. To assess promoter methylation status in a subgroup of short SGA subjects and controls. 292 Short prepubertal SGA children, 39 short young SGA adults and 85 young adults with normal stature. Short prepubertal SGA children received GH 1mg/m(2)/day. Fasting levels of IGF-I and IGFBP-3, baseline and delta height SDS. At baseline, IGFBP-3 levels were highest in SGA children with -202 AA genotype and lower in children with 1 or 2 copies of the C-allele (P<0.001). Children with C(-202)/C(-185) haplotype, compared to children with A(-202)/C(-185) haplotype, had lower IGFBP-3 levels (P=0.003) and were shorter (P=0.03). During GH treatment, children with C(-202)/C(-185) haplotype showed a significantly greater increase in IGFBP-3 SDS and in height SDS than children with A(-202)/C(-185) haplotype, resulting in similar IGFBP-3 levels and similar height SDS after 12 months of GH treatment. CpG methylation patterns showed a trend towards more methylation of CpGs involved in transcription factor binding in short young SGA adults compared to controls. Polymorphic variation in the IGFBP3 promoter region is correlated with IGFBP-3 levels, spontaneous growth and response to GH treatment in short SGA children.

  13. A novel role of IGFBP7 in mouse uterus: regulating uterine receptivity through Th1/Th2 lymphocyte balance and decidualization.

    Directory of Open Access Journals (Sweden)

    Zhen-Kun Liu

    Full Text Available Previously we have screened out Insulin-like Growth Factor Binding Protein 7 (IGFBP7 as a differentially expressed gene in post-implantation uterus versus pre-implantation uterus by suppressive subtractive hybridation. However its function in uterus was not clearly identified. In this research, the expression and function of IGFBP7 during post-implantation were studied. We found that IGFBP7 was mainly located in the glandular epithelium and the stroma, and was upregulated after embryo implantation. The vector pCR3.1-IGFBP7-t expressing partial IGFBP7 was constructed. Inhibition of IGFBP7 by specific DNA immunization induced significant reduction of implanted embryos and pregnancy rate. The number of implanted embryos (5.68 ± 0.46 was significantly reduced after immunization with pCR3.1-IGFBP7-t, as compared with that of the mice immunized with the control vector (12.29 ± 0.36 or saline (14.58 ± 0.40 (p<0.01. After specific inhibition of IGFBP7, the T helper type 1 (Th1 cytokine IFNγ, was significantly elevated (p<0.05 and the Th2 cytokines IL-4 and IL-10, were reduced in uteri (p<0.05. The increase of Tbet and the decrease of Gata3 were found in mice peripheral lymphocytes by flow cytometry. The expression of decidualization marker IGFBP1 and angiogenesis regulator VEGF were declined in uteri (p<0.05. The expression of apoptosis-associated proteins, caspase3 and Bcl-2, were also declined (p<0.05. These results showed that inhibition of IGFBP7 induced pregnancy failure by shifting uterine cytokines to Th1 type dominance and repressing uterine decidualization.

  14. Differential changes in free and total insulin-like growth factor I after major, elective abdominal surgery: the possible role of insulin-like growth factor-binding protein-3 proteolysis.

    Science.gov (United States)

    Skjaerbaek, C; Frystyk, J; Orskov, H; Kissmeyer-Nielsen, P; Jensen, M B; Laurberg, S; Møller, N; Flyvbjerg, A

    1998-07-01

    Major surgery is accompanied by extensive proteolysis of insulin-like growth factor (IGF)-binding protein-3 (IGFBP-3). Proteolysis of IGFBP-3 is generally believed to increase IGF bioavailability due to a diminished affinity of the IGFBP-3 fragments for IGFs. We have investigated 18 patients undergoing elective ileo-anal J-pouch surgery. Patients were randomized to treatment with GH (12 IU/day; n = 9) or placebo (n = 9) from 2 days before to 7 days after operation. Free IGF-I and IGF-II were measured by ultrafiltration of serum, and IGFBP-3 proteolytic activity was determined by a [125I]recombinant human IGFBP-3 degradation assay. In the GH-treated group, total IGF-I increased preoperatively by 99%. Postoperatively, total IGF-I decreased by 48% (placebo) and 52% (GH). Immunoassayable IGFBP-3 decreased by 27% (placebo) and 26% (GH). In the placebo-treated group, free IGF-I was unchanged throughout the study. In the GH-treated group, free IGF-I increased by 277% preoperatively and remained elevated after operation. IGFBP-3 proteolytic activity increased by 63-73% after operation. The relative elevations of free IGF-I levels despite decreased total IGF-I levels could thus relate to augmented IGFBP-3 proteolysis.

  15. Influence of The -202 A/C insulin-like growth factor-binding protein-3 promoter polymorphism on individual variation in height in Korean girls.

    Science.gov (United States)

    Yi, Min Ju; Park, Tae Young; Hwang, Il Tae; Yang, Seung

    2017-03-01

    The most common single nucleotide polymorphism in the IGFBP3 promoter region occurs at position -202. This polymorphic variation occurs frequently and may influence growth hormone responsiveness and somatic growth. However, the effects of IGFBP3 promoter polymorphism on growth in children are unknown. Restriction fragment length polymorphism-based genotyping of the -202 single nucleotide polymorphism was performed in 146 Korean girls aged between 15 and 16 years, who were selected randomly from the Seoul School Health Promotion Center. The participants were divided into 3 groups (tall, medium, and short) according to the height percentile established from normal reference values for Korean children. The serum levels of insulin-like growth factor I (IGF-I) and IGF-binding protein-3 (IGFBP-3) were then compared according to genotype. The genotype distribution in the participants was 79 AA (54.1%), 60 AC (41.1%), and 7 CC (4.8%). The C allele frequency at the -202 IGFBP3 position was 25.4% in this group. The mean serum IGFBP-3 concentration in girls with the AA genotype was higher than that in girls with the AC genotype in the medium (P=0.047) and short (P=0.035) groups, respectively. There was no difference in the IGF-I to IGFBP-3 molar ratio between the AA and AC genotype groups (P=0.161). In conclusion, the -202 polymorphism in the IGFBP3 promoter region is assumed to affect the serum concentration of IGFBP-3 in children as well as in adults. However, it is unclear whether this affects physical development according to the concentration of IGFBP-3.

  16. The joint effects of arsenic and risk diplotypes of insulin-like growth factor binding protein-3 in renal cell carcinoma.

    Science.gov (United States)

    Huang, Chao-Yuan; Huang, Ya-Li; Pu, Yeong-Shiau; Shiue, Horng-Sheng; Chen, Wei-Jen; Chen, Shih-Shan; Lin, Ying-Chin; Su, Chien-Tien; Hsueh, Yu-Mei

    2016-07-01

    The association between renal cell carcinoma (RCC) and diabetes mellitus (DM), alcohol consumption, insulin-like growth factor binding protein-3 (IGFBP-3) gene, and arsenic exposure, has been the subject of independent studies. However, few studies have examined the combined effect of these factors on RCC risk. The aim of this study was to examine the association between these risk factors and the odds ratio (OR) of RCC. A hospital-based case-control study was conducted in 398 RCC patients and 756 age- and gender-matched non-cancer controls. Genomic DNA was used to examine the genotype of IRS-1 (Gly972Arg), PI3-K (Met362Ile), IGFBP-3 (A[-202]C), and IGFBP-3 (C[-1590]A) by PCR-RFLP. Profiles of urinary arsenic were measured by high performance liquid chromatography linked with hydride generator and atomic absorption spectrometry. Participants who had never consumed alcohol and who had high total levels of urinary arsenic and DM had a high OR of RCC. IGFBP-3 (A[-202]C) and IGFBP-3 (C[-1590]A) were in linkage disequilibrium. Participants carrying high-risk IGFBP-3 diplotypes A-C/C-C, A-A/A-C, and C-A/C-A had a significantly higher odds ratio (OR) and 95% confidence interval (2.80, 1.91-4.12) of RCC compared to those carrying other IGFBP-3 diplotypes. This is the first study to show that borderline significant interaction of high total levels of urinary arsenic and IGFBP-3 high-risk diplotypes significantly enhanced the OR of RCC. Our data also provide evidence that subjects with more risk factors (e.g., high total levels of urinary arsenic, never consumed alcohol, IGFBP-3 high-risk diplotypes) may experience a higher OR of RCC.

  17. Continuous s.c. infusion rather than twice-daily injections of IGF-I more effectively increases serum IGF binding protein-3 in female monkeys.

    Science.gov (United States)

    Wilson, M E; Lackey, S L

    1999-09-01

    In order to better understand how the IGF-I axis is affected by exogenous IGF-I, this study compared the effects of a constant s.c. infusion of IGF-I with that of twice-daily injections of IGF-I in young adult female rhesus monkeys. Clinical studies suggest that circulating concentrations of insulin-like growth factor binding protein-3 (IGFBP-3) are decreased or unaffected by IGF-I administration, whereas acute increases in IGF-I may increase serum IGFBP-1. However, studies in monkeys indicate that acute or continuous infusion of IGF-I effectively increases serum IGFBP-3. Female monkeys were studied for 5 days with no IGF-I supplementation (baseline) and for 5 days of IGF-I treatment by either constant infusion (120 microg/kg per day s.c., n = 5) or twice-daily injections of IGF-I (60 microg/kg per injection s.c., n = 5). Serum samples were collected daily at 0800 h and at 0800, 0900, 1100, 1500, and 2000 h on days 1 and 4 for each condition. Samples were assayed for IGF-I, IGFBPs-1 and -3, insulin, and glucose. Serum IGF-I was consistently increased above baseline within 24 h of the initiation of constant infusion, but was delayed until the second day of treatment in the injection group. Serum IGFBP-3 followed the pattern of IGF-I, with concentrations increased by day 1 during constant infusion and by day 2 during intermittent injections. Although both treatments effectively increased serum IGFBP-3, the increase was greater during constant infusion (31% above baseline) compared with injection (17%). Immunoblotting revealed that the constant infusion of IGF-I resulted in quantitatively more lower-molecular-mass fragments of IGFBP-3 than were observed during baseline or intermittent injections. Size-exclusion chromatography and ultrafiltration indicated that most IGFBP-3 was found in the ternary complex, with a greater percentage found in the ternary complex during baseline (90%) than during constant infusion (86%) or intermittent injections of IGF-I (87%). In

  18. Interaction between IGFBP7 and insulin: a theoretical and experimental study

    Science.gov (United States)

    Ruan, Wenjing; Kang, Zhengzhong; Li, Youzhao; Sun, Tianyang; Wang, Lipei; Liang, Lijun; Lai, Maode; Wu, Tao

    2016-04-01

    Insulin-like growth factor binding protein 7 (IGFBP7) can bind to insulin with high affinity which inhibits the early steps of insulin action. Lack of recognition mechanism impairs our understanding of insulin regulation before it binds to insulin receptor. Here we combine computational simulations with experimental methods to investigate the interaction between IGFBP7 and insulin. Molecular dynamics simulations indicated that His200 and Arg198 in IGFBP7 were key residues. Verified by experimental data, the interaction remained strong in single mutation systems R198E and H200F but became weak in double mutation system R198E-H200F relative to that in wild-type IGFBP7. The results and methods in present study could be adopted in future research of discovery of drugs by disrupting protein–protein interactions in insulin signaling. Nevertheless, the accuracy, reproducibility, and costs of free-energy calculation are still problems that need to be addressed before computational methods can become standard binding prediction tools in discovery pipelines.

  19. Epidermal growth factor suppresses insulin-like growth factor binding protein 3 levels in human papillomavirus type 16-immortalized cervical epithelial cells and thereby potentiates the effects of insulin-like growth factor 1.

    Science.gov (United States)

    Hembree, J R; Agarwal, C; Eckert, R L

    1994-06-15

    Human ectocervical epithelial cells are a primary target for infection by oncogenic papillomaviruses, which are strongly implicated as causative agents in the genesis of cervical cancer. Growth factors have been implicated as agents that stimulate proliferation and enhance the possibility of malignant transformation. In the present study we utilize several human papillomavirus (HPV) type 16-immortalized ectocervical epithelial cell lines to investigate the effects of epidermal growth factor (EGF) and insulin-like growth factor I (IGF-I) on cell proliferation and the production of IGF binding proteins (IGFBPs). ECE16-1 cells, an HPV16-immortalized/nontumorigenic cell line, maintained in defined medium, produce and release high levels of IGFBP-3 (38/42 kDa) as well as smaller amounts of a 24-kDa IGFBP. Supplementation of defined medium with EGF causes a dose-dependent increase in cell growth and a concomitant decrease in the levels of IGFBP-3 released into the culture medium. EGF suppression of IGFBP-3 is maintained even when EGF-stimulated cell growth is suppressed 67% due to the simultaneous presence of 3 ng/ml of TGF beta 1, indicating that EGF suppression of IGFBP-3 levels is independent of EGF effects on cell growth. EGF suppression of IGFBP-3 production is correlated with a reduction in IGFBP-3 mRNA level. In the presence of EGF, the growth response of the cells to ng amounts of IGF-I is significantly enhanced. Moreover, the simultaneous presence of both EGF and IGF-I reduces the level of IGFBP-3 more efficiently than EGF alone. We also observe that the IGFBP-3 level is decreased and the 24-kDa IGFBP level is increased in HPV16-positive tumorigenic versus nontumorigenic cell lines. This is the first report of EGF acting as a positive regulator of IGF-I action via the IGFBPs. On the basis of these findings, we propose that EGF stimulates ECE16-1 cell growth via a dual-action mechanism by (a) stimulating growth directly via the EGF mitogenic pathway and (b

  20. Dysregulated DNA Methyltransferase 3A Upregulates IGFBP5 to Suppress Trophoblast Cell Migration and Invasion in Preeclampsia.

    Science.gov (United States)

    Jia, Yuanhui; Li, Ting; Huang, Xiaojie; Xu, Xianghong; Zhou, Xinyao; Jia, Linyan; Zhu, Jingping; Xie, Dandan; Wang, Kai; Zhou, Qian; Jin, Liping; Zhang, Jiqin; Duan, Tao

    2017-02-01

    Preeclampsia is a unique multiple system disorder during human pregnancy, which affects ≈5% to 8% of pregnancies. Its risks and complications have become the major causes of maternal and fetal morbidity and mortality. Although abnormal placentation to which DNA methylation dysregulation is always linked is speculated to be one of the reasons causing preeclampsia, the underlying mechanisms still remain elusive to date. Here we revealed that aberrant DNA methyltransferase 3A (DNMT3A) plays a critical role in preeclampsia. Our results show that the expression and localization of DNMT3A are dysregulated in preeclamptic placenta. Moreover, knockdown of DNMT3A obviously inhibits trophoblast cell migration and invasion. Mechanistically, IGFBP5 (insulin-like growth factor-binding protein 5), known as a suppressor, is upregulated by decreased DNMT3A because of promoter hypomethylation. Importantly, IGFBP5 downregulation can rescue the defects caused by DNMT3A knockdown, thereby, consolidating the significance of IGFBP5 in the downstream of DNMT3A in trophoblast. Furthermore, we detected low promoter methylation and high protein expression of IGFBP5 in the clinical samples of preeclamptic placenta. Collectively, our study suggests that dysregulation of DNMT3A and IGFBP5 is relevant to preeclampsia. Thus, we propose that DNMT3A and IGFBP5 can serve as potential markers and targets for the clinical diagnosis and therapy of preeclampsia. © 2017 American Heart Association, Inc.

  1. Proteomic screen identifies IGFBP7 as a novel component of endothelial cell-specific Weibel-Palade bodies.

    Science.gov (United States)

    van Breevoort, Dorothee; van Agtmaal, Ellen L; Dragt, Bieuwke S; Gebbinck, Jacqueline Klein; Dienava-Verdoold, Ilze; Kragt, Astrid; Bierings, Ruben; Horrevoets, Anton J G; Valentijn, Karine M; Eikenboom, Jeroen C; Fernandez-Borja, Mar; Meijer, Alexander B; Voorberg, Jan

    2012-05-04

    Vascular endothelial cells contain unique storage organelles, designated Weibel-Palade bodies (WPBs), that deliver inflammatory and hemostatic mediators to the vascular lumen in response to agonists like thrombin and vasopressin. The main component of WPBs is von Willebrand factor (VWF), a multimeric glycoprotein crucial for platelet plug formation. In addition to VWF, several other components are known to be stored in WPBs, like osteoprotegerin, monocyte chemoattractant protein-1 and angiopoetin-2 (Ang-2). Here, we used an unbiased proteomics approach to identify additional residents of WPBs. Mass spectrometry analysis of purified WPBs revealed the presence of several known components such as VWF, Ang-2, and P-selectin. Thirty-five novel candidate WPB residents were identified that included insulin-like growth factor binding protein-7 (IGFBP7), which has been proposed to regulate angiogenesis. Immunocytochemistry revealed that IGFBP7 is a bona fide WPB component. Cotransfection studies showed that IGFBP7 trafficked to pseudo-WPB in HEK293 cells. Using a series of deletion variants of VWF, we showed that targeting of IGFBP7 to pseudo-WPBs was dependent on the carboxy-terminal D4-C1-C2-C3-CK domains of VWF. IGFBP7 remained attached to ultralarge VWF strings released upon exocytosis of WPBs under flow. The presence of IGFBP7 in WPBs highlights the role of this subcellular compartment in regulation of angiogenesis.

  2. FETAL FIBRONECTIN AND PHOSPHORILATED INSULIN- LIKE GROWTH FACTOR BINDING PROTEIN-1 AS PREDICTORS OF SPONTANEUS PRETERM DELIVERY

    Directory of Open Access Journals (Sweden)

    Marija Hadži-Lega

    2014-09-01

    Full Text Available The aim of the paper was to assess the combined use of cervical length, fetal fibronectin and cervical phosphorylated insulin-like growth factor binding protein-1 (phIGFBP-1 in the prediction of preterm delivery in symptomatic women in the following 14 days. Cervical length was prospectively measured in 58 consecutive singleton pregnancies with intact membranes and regular contractions at 24–36 weeks; fetal fibronectin and phIGFBP-1 were also assessed. Demographic data was evaluated (history of previous preterm delivery, history of spontaneous abortion, parity, BMI, maternal age, Islamic or Orthodox religion. Values of all variables were evaluated (demographic data, cervical length and values of phIGFBP1 and fetal fibronectin alone and in combination with cervical length of ≤ 15mm and more than 15 mm. PhIGFPB was positive in 30 patients (22 of them gave birth in 14 days. In women with cervical length less than 15 mm phIGFBP-1, it was positive in 9 pregnant women who were delivered in 14 days. In women with cervical length less than 25 mm phIGFBP-1 was positive in 26 patients (2 of them gave birth in 14 days. In patients with cervical length more than 25 mm phIGFBP-1 was positive in 4 patients (2 of them gave birth in 14 days. Using logistic regression we confirmed that with OR 0.117 and CI 95% (0.046-0.295 and p<0.01 odds for preterm birth among patients with negative test results, phIGFBP-1 was by 0.117 lower than the odds for preterm birth among patients with positive test results. Using the same test, we confirmed that with OR=14,722 (CI 95% 5.27-41.1, (p<0.01 cervical length less than 25 mm was a good predictor of preterm delivery in symptomatic patients. Probability for delivery in the following 14 days in patients with positive phIGFBP-1 and cervical length≤15 mm is 0.88 or probability for not delivering in those patients is 0.12. Eighty-eight percents of patients with positive phIGFBP-1 and cervical length ≤15 mm will give birth

  3. Associations of insulin-like growth factor-I and its binding proteins and testosterone with frailty in older men.

    Science.gov (United States)

    Yeap, B B; Paul Chubb, S A; Lopez, Derrick; Ho, K K Y; Hankey, Graeme J; Flicker, Leon

    2013-05-01

    Ageing is associated with frailty and decreased anabolic hormones, insulin-like growth factor-I (IGF-I) and testosterone. We hypothesized that components of the IGF-I system, in conjunction with testosterone, modulate frailty risk in the elderly. We examined associations between IGF-I, its binding proteins IGFBP1 and IGFBP3 and testosterone with frailty in men. Observational study of 3 447 community-dwelling men aged 70-89 years assessed in 2001-04, with 1 654 reassessed in 2008-09. Baseline total IGF-I, IGFBP1, IGFBP3 and testosterone were assayed. Frailty was assessed using the FRAIL scale, comprising 5 domains: fatigue; difficulty climbing stairs; difficulty walking >100 m; >5 illnesses; weight loss >5%. Men with ≥ 3 domains were considered frail. At baseline, 527 men (15·3%) were frail. Frail men had lower IGFBP3 (3 630 ng/ml vs not frail: 3 800 ng/ml, P < 0·001) and comparable IGFBP1 (23·5 vs 21·5 ng/ml, P = 0·09). In multivariate analyses, higher IGFBP1 was associated with increased prevalence of frailty (highest vs lowest quartile Q4:Q1, adjusted odds ratio [OR] = 1·39, 95% CI = 1·03-1·88). New-onset frailty arose in 260 (17·5%) of 1 484 men. Lower baseline IGF-I predicted new-onset frailty (Q1:Q4 OR = 1·48, 95% CI = 1·00-2·20) as did higher IGFBP1 (Q4:Q1 OR = 1·59, 95% CI = 1·01-2·50). Men with both IGF-I and free testosterone in Q1 had greater odds of prevalent frailty (OR = 2·13, 95% CI = 1·54-2·95). Older men with higher IGFBP1 level, or both lower IGF-I and testosterone, are more likely to be frail, while those with lower IGF-I and higher IGFBP1 are more likely to become frail. Components of the IGF-I system may be biomarkers or independent predictors of frailty. © 2012 Blackwell Publishing Ltd.

  4. Urinary biomarkers TIMP-2 and IGFBP7 early predict acute kidney injury after major surgery.

    Directory of Open Access Journals (Sweden)

    Ivan Gocze

    Full Text Available To assess the ability of the urinary biomarkers IGFBP7 (insulin-like growth factor-binding protein 7 and TIMP-2 (tissue inhibitor of metalloproteinase 2 to early predict acute kidney injury (AKI in high-risk surgical patients.Postoperative AKI is associated with an increase in short and long-term mortality. Using IGFBP7 and TIMP-2 for early detection of cellular kidney injury, thus allowing the early initiation of renal protection measures, may represent a new concept of evaluating renal function.In this prospective study, urinary [TIMP-2]×[IGFBP7] was measured in surgical patients at high risk for AKI. A predefined cut-off value of [TIMP-2]×[IGFBP7] >0.3 was used for assessing diagnostic accuracy. Perioperative characteristics were evaluated, and ROC analyses as well as logistic regression models of risk assessment were calculated with and without a [TIMP-2]×[IGFBP7] test.107 patients were included in the study, of whom 45 (42% developed AKI. The highest median values of biomarker were detected in septic, transplant and patients after hepatic surgery (1.24 vs 0.45 vs 0.47 ng/l²/1000. The area under receiving operating characteristic curve (AUC for the risk of any AKI was 0.85, for early use of RRT 0.83 and for 28-day mortality 0.77. In a multivariable model with established perioperative risk factors, the [TIMP-2]×[IGFBP7] test was the strongest predictor of AKI and significantly improved the risk assessment (p<0.001.Urinary [TIMP-2]×[IGFBP7] test sufficiently detect patients with risk of AKI after major non-cardiac surgery. Due to its rapid responsiveness it extends the time frame for intervention to prevent development of AKI.

  5. Ligand binding mechanics of maltose binding protein.

    Science.gov (United States)

    Bertz, Morten; Rief, Matthias

    2009-11-13

    In the past decade, single-molecule force spectroscopy has provided new insights into the key interactions stabilizing folded proteins. A few recent studies probing the effects of ligand binding on mechanical protein stability have come to quite different conclusions. While some proteins seem to be stabilized considerably by a bound ligand, others appear to be unaffected. Since force acts as a vector in space, it is conceivable that mechanical stabilization by ligand binding is dependent on the direction of force application. In this study, we vary the direction of the force to investigate the effect of ligand binding on the stability of maltose binding protein (MBP). MBP consists of two lobes connected by a hinge region that move from an open to a closed conformation when the ligand maltose binds. Previous mechanical experiments, where load was applied to the N and C termini, have demonstrated that MBP is built up of four building blocks (unfoldons) that sequentially detach from the folded structure. In this study, we design the pulling direction so that force application moves the two MBP lobes apart along the hinge axis. Mechanical unfolding in this geometry proceeds via an intermediate state whose boundaries coincide with previously reported MBP unfoldons. We find that in contrast to N-C-terminal pulling experiments, the mechanical stability of MBP is increased by ligand binding when load is applied to the two lobes and force breaks the protein-ligand interactions directly. Contour length measurements indicate that MBP is forced into an open conformation before unfolding even if ligand is bound. Using mutagenesis experiments, we demonstrate that the mechanical stabilization effect is due to only a few key interactions of the protein with its ligand. This work illustrates how varying the direction of the applied force allows revealing important details about the ligand binding mechanics of a large protein.

  6. Serum IGFBP-2 and Risk of Atypical Hyperplasia of the Breast

    Science.gov (United States)

    Catsburg, Chelsea; Gunter, Marc J.; Tinker, Lesley; Chlebowski, Rowan T.; Pollak, Michael; Strickler, Howard D.; Cote, Michele L.; Page, David L.; Rohan, Thomas E.

    2015-01-01

    Atypical hyperplasia of the breast (AH) is associated with increased risk of subsequent invasive breast cancer, yet little is known about the etiology of AH. Insulin-like growth factor binding protein 2 (IGFBP-2) may contribute to the development of AH due to its proliferative effects on mammary tissue. We conducted a nested case-control study of postmenopausal women enrolled in Women's Health Initiative-Clinical Trial. Cases were 275 women who developed incident AH during follow-up, individually (1 : 1) matched to controls. Levels of IGFBP-2 were determined from fasting serum collected at baseline. Multivariable conditional logistic regression models were used to estimate odds ratios for the association of IGFBP-2 with risk of AH. Serum IGFBP-2 was associated with a nonsignificant decrease in risk for AH, when comparing the highest quartile to lowest quartile (OR = 0.65; 95% CI = 0.32–1.31). This decrease in risk was most evident when analyses were restricted to nondiabetic, nonusers of hormone therapy (OR = 0.33, 95% CI = 0.13–0.86, ptrend = 0.06) and nondiabetic women who were overweight or obese (OR = 0.43, 95% CI = 0.18–1.03, ptrend = 0.05). Results from this study provide some support for an inverse association between serum IGFBP2 levels and risk of AH, particularly in nondiabetic women who are overweight or obese. Further studies are required to confirm these results. PMID:26106415

  7. Assessing the role of insulin-like growth factors and binding proteins in prostate cancer using Mendelian randomization

    DEFF Research Database (Denmark)

    Bonilla, Carolina; Lewis, Sarah J; Rowlands, Mari-Anne

    2016-01-01

    Circulating insulin-like growth factors (IGFs) and their binding proteins (IGFBPs) are associated with prostate cancer. Using genetic variants as instruments for IGF peptides, we investigated whether these associations are likely to be causal. We identified from the literature 56 single nucleotide...... to estimate the causal effect of circulating IGF peptides on prostate cancer. Published SNPs in the IGFBP1/IGFBP3 gene region, particularly rs11977526, were strong instruments for IGF-II and IGFBP-3, less so for IGF-I. Rs11977526 was associated with high (vs. low) Gleason grade (OR per IGF-II/IGFBP-3 level......-raising allele 1.05; 95% CI: 1.00, 1.10). Using rs11977526 as an IV we estimated the causal effect of a one SD increase in IGF-II (∼265 ng/mL) on risk of high vs. low grade disease as 1.14 (95% CI: 1.00, 1.31). Because of the potential for pleiotropy of the genetic instruments, these findings can only causally...

  8. Cycle modulation of insulin-like growth factor-binding protein 1 in human endometrium

    Directory of Open Access Journals (Sweden)

    Corleta H.

    2000-01-01

    Full Text Available Endometrium is one of the fastest growing human tissues. Sex hormones, estrogen and progesterone, in interaction with several growth factors, control its growth and differentiation. Insulin-like growth factor 1 (IGF-1 interacts with cell surface receptors and also with specific soluble binding proteins. IGF-binding proteins (IGF-BP have been shown to modulate IGF-1 action. Of six known isoforms, IGF-BP-1 has been characterized as a marker produced by endometrial stromal cells in the late secretory phase and in the decidua. In the current study, IGF-1-BP concentration and affinity in the proliferative and secretory phase of the menstrual cycle were measured. Endometrial samples were from patients of reproductive age with regular menstrual cycles and taking no steroid hormones. Cytosolic fractions were prepared and binding of 125I-labeled IGF-1 performed. Cross-linking reaction products were analyzed by SDS-polyacrylamide gel electrophoresis (7.5% followed by autoradiography. 125I-IGF-1 affinity to cytosolic proteins was not statistically different between the proliferative and secretory endometrium. An approximately 35-kDa binding protein was identified when 125I-IGF-1 was cross-linked to cytosol proteins. Secretory endometrium had significantly more IGF-1-BP when compared to proliferative endometrium. The specificity of the cross-linking process was evaluated by the addition of 100 nM unlabeled IGF-1 or insulin. Unlabeled IGF-1 totally abolished the radioactivity from the band, indicating specific binding. Insulin had no apparent effect on the intensity of the labeled band. These results suggest that IGF-BP could modulate the action of IGF-1 throughout the menstrual cycle. It would be interesting to study this binding protein in other pathologic conditions of the endometrium such as adenocarcinomas and hyperplasia.

  9. Changes in serum concentrations of growth hormone, insulin, insulin-like growth factor and insulin-like growth factor-binding proteins 1 and 3 and urinary growth hormone excretion during the menstrual cycle

    DEFF Research Database (Denmark)

    Juul, A; Scheike, Thomas Harder; Pedersen, A T

    1997-01-01

    Few studies exist on the physiological changes in the concentrations of growth hormone (GH), insulin-like growth factors (IGF) and IGF-binding proteins (IGFBP) within the menstrual cycle, and some controversy remains. We therefore decided to study the impact of endogenous sex steroids on the GH......-IGF-IGFBP axis during the ovulatory menstrual cycle in 10 healthy women (aged 18-40 years). Blood sampling and urinary collection was performed every morning at 0800 h for 32 consecutive days. Every second day the subjects were fasted overnight before blood sampling. Follicle stimulating hormone, luteinizing...... hormone (LH), oestradiol, progesterone, IGF-I, IGFBP-3, sex hormone-binding globulin, dihydroepiandrosterone sulphate and GH were determined in all samples, whereas insulin and IGFBP-1 were determined in fasted samples only. Serum IGF-I concentrations showed some fluctuation during the menstrual cycle...

  10. miR-204-5p suppresses cell proliferation by inhibiting IGFBP5 in papillary thyroid carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Lianyong; Wang, Jingnan; Li, Xiangqi; Ma, Junhua; Shi, Chao; Zhu, Hongling; Xi, Qian; Zhang, Jichen; Zhao, Xuemei; Gu, Mingjun, E-mail: mjgugonglihos@yeah.net

    2015-02-20

    microRNAs (miRNAs) are frequently dysregulated in human malignancies. It was recently shown that miR-204-5p is downregulated in papillary thyroid carcinoma (PTC); however, the functional significance of this observation is not known. This study investigated the role of miR-204-5p in PTC. Overexpressing miR-204-5p suppressed PTC cell proliferation and induced cell cycle arrest and apoptosis. The results of a luciferase reporter assay showed that miR-204-5p can directly bind to the 3′ untranslated region (UTR) of insulin-like growth factor-binding protein 5 (IGFBP5) mRNA, and IGFBP5 overexpression partially reversed the growth-inhibitory effects of miR-204-5p. These results indicate that miR-204-5p acts as a tumor suppressor in PTC by regulating IGFBP5 expression and that miR-204-5p can potentially serve as an antitumorigenic agent in the treatment of PTC. - Highlights: • miR-204-5p expression is downregulated in PTC tissues and cell lines. • miR-204-5p suppresses proliferation and promotes apoptosis in PTC cells. • miR-204-5p suppresses IGFBP5 expression by direct binding to the 3′-UTR. • IGFBP5 overexpression reverses the effects of miR-204-5p.

  11. Insulin-like growth factor (IgF-I, IgF binding protein-3, and prostate cancer: correlation with gleason score

    Directory of Open Access Journals (Sweden)

    Lívia L. Corrêa

    2015-02-01

    Full Text Available Introduction Non-androgenic growth factors are involved in the growth regulation of prostate cancer (PCa. Objective This is the first Brazilian study to correlate, in a population of patients operated for PCa, PSA, total testosterone, insulin-like growth factor-I (IGF-I and insulin-like growth factor-binding protein-3 (IGFBP-3 with Gleason score and to compare with a control group with benign prostate hyperplasia (BPH. Materials and Methods This retrospective single-center study included 49 men with previously diagnosed PCa and 45 with previously diagnosed BPH. PSA, testosterone, IGF-I, IGFBP-3 were determined in both groups. Results PSA and IGFBP-3 levels were significantly higher in the PCa group as compared to the BPH group (p<0.001 and p=0.004, respectively. There was a significant difference when we compared the PSA before surgery (p<0.001 and at the inclusion in the study (p<0.001 and IGFBP3 (0.016 among patients with Gleason <7, ≥7 and BPH. In the PCa group, PSA, testosterone, IGF-I and IGFBP-3 levels were comparable between Gleason <7 and ≥7. Conclusions Our data suggest that in localized PCa, the quantification of PSA and, not of IGF-1, may provide independent significant information in the aggressiveness. IGFBP-3 could be a biochemical marker of disease control in PCa patients.

  12. DNA Polymorphism of Insulin-like Growth Factor-binding Protein-3 Gene and Its Association with Cashmere Traits in Cashmere Goats

    Directory of Open Access Journals (Sweden)

    Haiying Liu

    2012-11-01

    Full Text Available Insulin-like growth factor binding protein-3 (IGFBP-3 gene is important for regulation of growth and development in mammals. The present investigation was carried out to study DNA polymorphism by PCR-RFLP of IGFBP-3 gene and its effect on fibre traits of Chinese Inner Mongolian cashmere goats. The fibre traits data investigated were cashmere fibre diameter, combed cashmere weight, cashmere fibre length and guard hair length. Four hundred and forty-four animals were used to detect polymorphisms in the hircine IGFBP-3 gene. A 316-bp fragment of the IGFBP-3 gene in exon 2 was amplified and digested with HaeIII restriction enzyme. Three patterns of restriction fragments were observed in the populations. The frequency of AA, AB and BB genotypes was 0.58, 0.33 and 0.09 respectively. The allelic frequency of the A and B allele was 0.75 and 0.25 respectively. Nucleotide sequencing revealed a C>G transition in the exon 2 region of the IGFBP-3 gene resulting in R158G change which caused the polymorphism. Least squares analysis revealed a significant effect of genotypes on cashmere weight (p0.05. The animals of AB and BB genotypes showed higher cashmere weight, cashmere fibre length and hair length than the animals possessing AA genotype. These results suggested that polymorphisms in the hircine IGFBP-3 gene might be a potential molecular marker for cashmere weight in cashmere goats.

  13. Relationship between leptin, insulin resistance, insulin-like growth factor-1 and insulin-like growth factor binding protein-3 in patients with chronic kidney disease.

    Science.gov (United States)

    Atamer, A; Alisir Ecder, S; Akkus, Z; Kocyigit, Y; Atamer, Y; Ilhan, N; Ecder, T

    2008-01-01

    This study examined the relationship between leptin, insulin-like growth factor-1 (IGF-1), IGF binding protein-3 (IGFBP-3) and insulin resistance in patients with chronic kidney disease (CKD). Levels of leptin, insulin, IGF-1, IGFBP-3 and common routine parameters were measured in 45 patients (23 males and 22 females) with CKD and 45 healthy controls matched for age, gender and body mass index. IGF-1 and IGFBP-3 levels were measured using a two-site immunoradiometric assay. Leptin levels were measured using an enzyme-linked immunosorbent assay. A homeostasis model assessment computer-solved model was used to assess insulin resistance (HOMA-IR). Levels of serum leptin, insulin, IGF-1, IGFBP-3 and HOMA-IR were significantly increased in patients with CKD compared with healthy subjects, whereas fasting blood glucose was not significantly different between the two groups. In patients with CKD, the serum leptin level was significantly correlated with IGF-1, IGFBP-3 and HOMA-IR. In conclusion, this study suggests that there is an interaction between leptin, IGF-1, IGFBP-3 and insulin resistance in patients with CKD.

  14. Effect of i.p. insulin administration onIGF1 and IGFBP1 in type1 diabetes

    NARCIS (Netherlands)

    van Dijk, P. R.; Logtenberg, S. J. J.; Groenier, K. H.; Kleefstra, N.; Bilo, H. J. G.; Arnqvist, H. J.

    2014-01-01

    In type 1 diabetes mellitus (T1DM), low concentrations of IGF1 and high concentrations of IGF-binding protein 1 (IGFBP1) have been reported. It has been suggested that these abnormalities in the GH-IGF1 axis are due to low insulin concentrations in the portal vein. We hypothesized that the i.p.

  15. Variation of plasma IGFBP-2 level in patients with glioblastoma after combined therapy%血浆IGFBP-2在脑胶质母细胞瘤治疗前后变化

    Institute of Scientific and Technical Information of China (English)

    周开甲; 江涛; 李桂林; 徐莉

    2008-01-01

    目的 探讨脑胶质瘤病人血浆类胰岛素样生长因子结合蛋白2(insulin-like growthfactor binding protein 2,IGFBP-2)浓度动态监测在病人病情判定、预测复发中的临床意义.方法 用酶联免疫法(ELISA)对健康体检者、不同级别胶质瘤及胶质母细胞瘤病人综合治疗后复发前后血浆IGFBP-2浓度进行统计学比较,随访其中55例胶质母细胞瘤病人2.5年,分析术前血浆IGFBP-2的浓度与其无瘤生存期的关系.结果 血浆IGFBP-2浓度随着胶质瘤级别的升高而增加(F=17.745,P=0.000);胶质母细胞瘤病人经过手术、放疗、化疗综合治疗后,未复发病人血浆IGFBP-2明显下降(t=2.164,P=0.041),而复发后明显升高(t=8.295,P=0.000);血浆中IGFBP-2浓度600ng/ml的胶质母细胞瘤病人(Z=2.272,P=0.023).结论 血浆IGFBP-2浓度的动态监测对判定胶质瘤病人病变恶性程度、预测胶质母细胞瘤的复发有一定的临床意义.%Objective To investigate the clinical significance of detecting insulin like growth factor binding protein 2 (IGFBP-2) in the plasma of patients with glioma in judging glioma grade, predicting glioma recurrence. Method The plasma IGFBP-2 level was measured by enzyme linked immunosorbent assay ( ELISA ) in 51 cases with WHO 2 glioma, 26 cases with anaplasia glioma, 56 cases with glioblastoma, 30 cases with anaplasia glioma, 56 cases with glioblastoma, 30 healthy controls, and patients with glioblastoma before and after receiving combined therapy. Meanwhile, analyse the relation of plasma IGFBP-2 level and patients'survival without glioma recurrence in patients with glioblastoma after receiving combined therapy. One-way ANOVA, LSD, independent-samples t test, paired-samples t test and Kaplan-Meier were used to analyse the IGFBP-2 level between different groups. Results The plasma IGFBP-2 level in patients with high-grade glioma was significantly higher than low-grade glioma and healthy controls ( F =17.745 ,P =0.000) ; the

  16. A temporal switch in the insulin-signalling pathway that regulates hepatic IGF-binding protein-1 gene expression

    OpenAIRE

    2006-01-01

    PUBLISHED Insulin regulation of hepatic gene transcription is a vital component of glucose homeostasis. Understanding the molecular regulationof thisprocess aids the searchfor the defect(s) that promotesinsulin-resistant states, such asdiabetesmellitus. We havepreviously shownthat the insulin regulationof hepatic IGF-binding protein-1 (IGFBP1) expression requiresthe signalling proteins phosphatidylinositol 3-kinase (PI 3-kinase) and mammalian target of rapamycin (mTOR). In this report, we ...

  17. Effects of tibolone and its metabolites on prolactin and insulin-like growth factor binding protein-1 expression in human endometrial stromal cells.

    Science.gov (United States)

    Guzel, Elif; Buchwalder, Lynn; Basar, Murat; Kayisli, Umit; Ocak, Nehir; Bozkurt, Idil; Lockwood, Charles J; Schatz, Frederick

    2015-05-01

    The effects of the postmenopausal replacement steroid tibolone and its 3α-, 3β-OH and Δ-4 tibolone metabolites were evaluated on progesterone receptor-mediated classic decidualization markers insulin-like growth factor binding protein-1 (IGFBP-1) and prolactin expression in human endometrial stromal cells (HESCs). Supernatants of conditioned medium or erxtracted RNA from experimental cell incubations of confluent HESCs were subjected to ELISAs, Western blot analysis and RT/PCR, and results were statisically assesed. Over 21 days, specific ELISAs observed linear increases in secreted IGFBP-1 and prolactin levels elicited by tibolone and its metabolites. Cultured HESCs were refractory to E2 and dexamethasone, whereas tibolone and each metabolite exceeded medroxyprogesterone acetate in significantly elevating IGFBP-1 and prolactin output. Anti-progestins eliminated IGFBP-1 and prolactin induction by tibolone and its metabolites. Immunoblotting and RT/PCR confirmed ELISA results. These observations of IGFBP-1 and prolactin expression: (a) indicate the relevance of cultured HESCs in evaluating the chronic effects of tibolone administration to women; (b) are consistent with PR-mediated endometrial atrophy and protection against endometrial bleeding despite the persistence of circulating ER-binding, but not PR-binding metabolites following tibolone administration to women.

  18. The relationship between maternal insulin-like growth factors 1 and 2 (IGF-1, IGF-2) and IGFBP-3 to gestational age and preterm delivery.

    LENUS (Irish Health Repository)

    Cooley, Sharon M

    2012-02-01

    AIMS: To investigate the relationship between levels of insulin-like growth factors 1 and 2 (IGF-1, IGF-2), and insulin-like growth factor binding protein 3 (IGFBP-3) in antenatal maternal serum and gestational age at delivery. METHODS: Prospective cohort study of 1650 low-risk Caucasian women in a London University teaching hospital. Maternal IGF-1, IGF-2 and IGFBP-3 were measured in maternal blood at booking and analyzed with respect to gestational age at delivery. RESULTS: There was no significant association between maternal IGF-1 or IGF-2 and preterm birth (PTB). A significant reduction in mean IGFBP-3 levels was noted with delivery <32 completed weeks (P=0.02). CONCLUSION: Maternal mean IGFBP-3 levels are significantly reduced in cases complicated by delivery <32 completed weeks.

  19. Insulin-like growth factor binding proteins: regulation in chronic active plaques in multiple sclerosis and functional analysis of glial cells

    NARCIS (Netherlands)

    Chesik, D.; De Keyser, J.; Glazenburg, L.; Wilczak, N.

    2006-01-01

    Studies in experimental allergic encephalomyelitis, an animal model of multiple sclerosis (MS), suggest that astrocyte-secreted insulin-like growth factor binding protein-2 (IGFBP-2) helps target IGF-1 to IGF-1 receptor-expressing oligodendrocytes and promote remyelination. We examined the presence

  20. Insulin-like growth factor binding proteins : regulation in chronic active plaques in multiple sclerosis and functional analysis of glial cells

    NARCIS (Netherlands)

    Chesik, Daniel; De Keyser, Jacques; Glazenburg, Lisa; Wilczak, Nadine

    2006-01-01

    Studies in experimental allergic encephalomyelitis, an animal model of multiple sclerosis (MS), suggest that astrocyte-secreted insulin-like growth factor binding protein-2 (IGFBP-2) helps target IGF-1 to IGF-1 receptor-expressing oligodendrocytes and promote remyelination. We examined the presence

  1. Insulin-like growth factor binding proteins : regulation in chronic active plaques in multiple sclerosis and functional analysis of glial cells

    NARCIS (Netherlands)

    Chesik, Daniel; De Keyser, Jacques; Glazenburg, Lisa; Wilczak, Nadine

    Studies in experimental allergic encephalomyelitis, an animal model of multiple sclerosis (MS), suggest that astrocyte-secreted insulin-like growth factor binding protein-2 (IGFBP-2) helps target IGF-1 to IGF-1 receptor-expressing oligodendrocytes and promote remyelination. We examined the presence

  2. Serum insulin-like growth factor-binding protein-2 levels and metabolic and cardiovascular risk factors in young adults and children born small for gestational age

    NARCIS (Netherlands)

    S.W.K. de Kort (Sandra); J. van Doorn (Jaap); A.G.M. van de Sande (Ad); R.W.J. Leunissen (Ralph); A.C.S. Hokken-Koelega (Anita)

    2010-01-01

    textabstractBackground: IGF binding protein (IGFBP)-2 might protect against cardiovascular disease. Small for gestational age (SGA) birth could be associated with a higher risk for type 2 diabetes mellitus and cardiovascular disease in later life. No data are available on the relationship between

  3. A prospective study on circulating insulin-like growth factor I (IGF-I), IGF-binding proteins, and cognitive function in the elderly

    NARCIS (Netherlands)

    S. Kalmijn (Sandra); H.A.P. Pols (Huib); S.W.J. Lamberts (Steven); M.M.B. Breteler (Monique); J.A.M.J.L. Janssen (Joseph)

    2000-01-01

    textabstractThe objective of this study was to investigate the longitudinal relation between the insulin-like growth factor I (IGF-I)/IGF-binding protein (IGFBP) system and cognitive function. The study population consisted of a sample of 186 healthy participants from the populatio

  4. The influence of hepatitis B virus on the expression of insulin-like growth factor-binding protein 7 and its ;clinical significance%乙型肝炎病毒对胰岛素样生长因子结合蛋白7表达的影响及其临床意义

    Institute of Scientific and Technical Information of China (English)

    宋惠; 刘兴晖; 祝成亮; 钟基大; 李毅

    2013-01-01

    目的:探讨乙型肝炎病毒(HBV)对胰岛素样生长因子结合蛋白7(IGFBP7)表达的影响及其临床意义。方法逆转录-聚合酶链反应(PCR)检测IGFBP7 mRNA的表达水平,酶联免疫吸附试验(ELISA)检测血清IGFBP7含量,分析IGFBP7在慢性乙型肝炎(CHB)、肝纤维化(LC)和肝细胞癌(HCC)患者间血清含量的差异。结果 IGFBP7 mRNA在HepG2.2.15细胞中的表达水平较HepG2高;与健康对照组相比,HBV感染者IGFBP7血清学水平明显升高(P<0.05);IGFBP7在LC和HCC患者低于CHB患者(P<0.05)。结论 HBV能够上调IGFBP7的表达,其血清水平与疾病进程呈负相关。%Objective To investigate the influence of hepatitis B virus(HBV)on the expression of insulin-like growth factor-binding protein 7(IGFBP7)and its clinical significance.Methods The mRNA expression of IGFBP7 was measured by reverse transcription-polymerase chain reaction (PCR),and serum levels of IGFBP7 were measured by enzyme-linked immunosorbent assay(ELISA).The different expressions of IGFBP7 among patients with chronic hepatitis B(CHB),liver cirrhosis(LC)and hepatocellular carcinoma(HCC)were analyzed.Results The expression of IGFBP7 mRNA was higher in HepG2.2.15 cells than in HepG2 cells.Compared with healthy controls,serum IGFBP7 levels were much higher in HBV patients (P<0.05),and the serum levels of IGFBP7 were detected at lower levels in patients with LC and HCC than those with CHB(P<0.05).Conclusions HBV can upregulate the expression of IGFBP7, which is negatively correlated with the disease progression.

  5. Proportionate Dwarfism in Mice Lacking Heterochromatin Protein 1 Binding Protein 3 (HP1BP3) Is Associated With Alterations in the Endocrine IGF-1 Pathway.

    Science.gov (United States)

    Garfinkel, Benjamin P; Arad, Shiri; Le, Phuong T; Bustin, Michael; Rosen, Clifford J; Gabet, Yankel; Orly, Joseph

    2015-12-01

    Heterochromatin protein 1 binding protein 3 (HP1BP3) is a recently described histone H1-related protein with roles in chromatin structure and transcriptional regulation. To explore the potential physiological role of HP1BP3, we have previously described an Hp1bp3(-/-) mouse model with reduced postnatal viability and growth. We now find that these mice are proportionate dwarfs, with reduction in body weight, body length, and organ weight. In addition to their small size, microcomputed tomography analysis showed that Hp1bp3(-/-) mice present a dramatic impairment of their bone development and structure. By 3 weeks of age, mice of both sexes have severely impaired cortical and trabecular bone, and these defects persist into adulthood and beyond. Primary cultures of both osteoblasts and osteoclasts from Hp1bp3(-/-) bone marrow and splenocytes, respectively, showed normal differentiation and function, strongly suggesting that the impaired bone accrual is due to noncell autonomous systemic cues in vivo. One major endocrine pathway regulating both body growth and bone acquisition is the IGF regulatory system, composed of IGF-1, the IGF receptors, and the IGF-binding proteins (IGFBPs). At 3 weeks of age, Hp1bp3(-/-) mice exhibited a 60% reduction in circulating IGF-1 and a 4-fold increase in the levels of IGFBP-1 and IGFBP-2. These alterations were reflected in similar changes in the hepatic transcripts of the Igf1, Igfbp1, and Igfbp2 genes. Collectively, these results suggest that HP1BP3 plays a key role in normal growth and bone development by regulating transcription of endocrine IGF-1 components.

  6. Insulin-like growth factor binding protein-3 in preterm infants with retinopathy of prematurity

    Directory of Open Access Journals (Sweden)

    Manizheh Mostafa Gharehbaghi

    2012-01-01

    Full Text Available Background: Retinopathy of prematurity (ROP is the main cause of visual impairment in preterm newborn infants. Objective: This study was conducted to determine whether insulin-like growth factor binding protein -3 (IGFBP-3 is associated with proliferative ROP and has a role in pathogenesis of the disease in premature infants. Materials and Methods: A total of 71 preterm infants born at or before 32 weeks of gestation participated in this study. Studied patients consisted of 41 neonates without vaso-proliferative findings of ROP as the control group and 30 preterm infants with evidence of severe ROP in follow up eye examination as the case group. Blood samples obtained from these infants 6-8 weeks after birth and blood levels of IGFBP-3 were measured using enzyme-linked immunosorbent assay (ELISA. Results: The mean gestation age and birth weight of the studied patients were 28.2±1.6 weeks and 1120.7±197 gram in the case group and 28.4±1.6 weeks and 1189.4±454 gram in the control group (P=0.25 and P=0.44 respectively. The infants in the case group had significantly lower Apgar score at first and 5 min after birth. Insulin-like growth factor binding protein -3 (IGFBP-3 was significantly lower in the patients with proliferative ROP than the patients without ROP [592.5±472.9 vs. 995.5±422.2 ng/ml (P=0.009]. Using a cut-off point 770.45 ng/ml for the plasma IGFBP-3, we obtained a sensitivity of 65.9% and a specificity of 66.7% in the preterm infants with vasoproliferative ROP. Conclusion: Our data demonstrated that the blood levels IGFBP-3 was significantly lower in the patients with ROP and it is suspected that IGFBP-3 deficiency in the premature infants may have a pathogenetic role in proliferative ROP.

  7. Knockout maternal adiponectin increases fetal growth in mice: potential role for trophoblast IGFBP-1.

    Science.gov (United States)

    Qiao, Liping; Wattez, Jean-Sebastien; Lee, Samuel; Guo, Zhuyu; Schaack, Jerome; Hay, William W; Zita, Matteo Moretto; Parast, Mana; Shao, Jianhua

    2016-11-01

    The main objective of this study was to investigate whether maternal adiponectin regulates fetal growth through the endocrine system in the fetal compartment. Adiponectin knockout (Adipoq (-/-) ) mice and in vivo adenovirus-mediated reconstitution were used to study the regulatory effect of maternal adiponectin on fetal growth. Primary human trophoblast cells were treated with adiponectin and a specific peroxisome proliferator-activated receptor α (PPARα) agonist or antagonist to study the underlying mechanism through which adiponectin regulates fetal growth. The body weight of fetuses from Adipoq (-/-) dams was significantly greater than that of wild-type dams at both embryonic day (E)14.5 and E18.5. Adenoviral vector-mediated maternal adiponectin reconstitution attenuated the increased fetal body weight induced by maternal adiponectin deficiency. Significantly increased blood glucose, triacylglycerol and NEFA levels were observed in Adipoq (-/-) dams, suggesting that nutrient supply contributes to maternal adiponectin-regulated fetal growth. Although fetal blood IGF-1 concentrations were comparable in fetuses from Adipoq (-/-) and wild-type dams, remarkably low levels of IGF-binding protein 1 (IGFBP-1) were observed in the serum of fetuses from Adipoq (-/-) dams. IGFBP-1 was identified in the trophoblast cells of human and mouse placentas. Maternal fasting robustly increased IGFBP-1 levels in mouse placentas, while reducing fetal weight. Significantly low IGFBP-1 levels were found in placentas of Adipoq (-/-) dams. Adiponectin treatment increased IGFBP-1 levels in primary cultured human trophoblast cells, while the PPARα antagonist, MK886, abolished this stimulatory effect. These results indicate that, in addition to nutrient supply, maternal adiponectin inhibits fetal growth by increasing IGFBP-1 expression in trophoblast cells.

  8. Genomewide meta-analysis identifies loci associated with IGF-I and IGFBP-3 levels with impact on age-related traits

    NARCIS (Netherlands)

    A. Teumer (Alexander); Q. Qi; M. Nethander (Maria); H. Aschard (Hugues); S. Bandinelli (Stefania); M. Beekman (Marian); S.I. Berndt (Sonja); M. Bidlingmaier (Martin); L. Broer (Linda); A.R. Cappola (Anne); Ceda, G.P. (Gian Paolo); S.J. Chanock (Stephen); M.-H. Chen (Ming-Huei); Chen, T.C. (Tai C.); Y.D. Chen (Y.); Chung, J. (Jonathan); Del Greco Miglianico, F. (Fabiola); J. Eriksson (Joel); L. Ferrucci (Luigi); N. Friedrich (Nele); C. Gnewuch (Carsten); M. Goodarzi (Mark); N. Grarup (Niels); Guo, T. (Tingwei); Hammer, E. (Elke); R.B. Hayes (Richard); A.A. Hicks (Andrew); A. Hofman (Albert); J.J. Houwing-Duistermaat (Jeanine); Hu, F. (Frank); D. Hunter (David); L.L.N. Husemoen (Lise Lotte); A.J. Isaacs (Aaron); K.B. Jacobs (Kevin); J.A.M.J.L. Janssen (Joseph); J.-O. Jansson (John-Olov); Jehmlich, N. (Nico); Johnson, S. (Simon); A. Juul (Anders); M. Karlsson (Magnus); T.O. Kilpeläinen (Tuomas); P. Kovacs (Peter); P. Kraft (Peter); Li, C. (Chao); A. Linneberg (Allan); Y. Liu (Yongmei); R.J.F. Loos (Ruth); M. Lorentzon (Mattias); Y. Lu (Yingchang); M. Maggio (Marcello); R. Mägi (Reedik); J.B. Meigs (James); D. Mellström (Dan); M. Nauck (Matthias); A.B. Newman (Anne B.); M.N. Pollak (Michael); P.P. Pramstaller (Peter Paul); I. Prokopenko (Inga); B.M. Psaty (Bruce); M. Reincke (Martin); E.B. Rimm (Eric B.); Rotter, J.I. (Jerome I.); Saint Pierre, A. (Aude); C. Schurmann (Claudia); S. Seshadri (Sudha); Sjögren, K. (Klara); P.E. Slagboom (Eline); Strickler, H.D. (Howard D.); M. Stumvoll (Michael); Y. Suh (Yousin); Q. Sun (Qi); Zhang, C. (Cuilin); Svensson, J. (Johan); T. Tanaka (Toshiko); Tare, A. (Archana); A. Tönjes (Anke); H.-W. Uh (Hae-Won); C.M. van Duijn (Cock); D. van Heemst (Diana); L. Vandenput (Liesbeth); R.S. Vasan (Ramachandran Srini); U. Völker (Uwe); S.M. Willems (Sara); C. Ohlsson (Claes); H. Wallaschofski (Henri); R.C. Kaplan (Robert)

    2016-01-01

    textabstractThe growth hormone/insulin-like growth factor (IGF) axis can be manipulated in animal models to promote longevity, and IGF-related proteins including IGF-I and IGF-binding protein-3 (IGFBP-3) have also been implicated in risk of human diseases including cardiovascular diseases, diabetes,

  9. Serum insulin-like growth factor I (IGF-I) and IGF-binding protein 3 levels are increased in central precocious puberty

    DEFF Research Database (Denmark)

    Juul, A; Scheike, Thomas Harder; Nielsen, C T

    1995-01-01

    Central precocious puberty (CPP) is characterized by early activation of the pituitary-gonadal axis, which leads to increased growth velocity and development of secondary sexual characteristics. It is generally believed that gonadal sex steroids stimulate pulsatile GH secretion, which, in turn......, stimulates insulin-like growth factor I (IGF-I) and IGF-binding protein 3 (IGFBP-3) production. However, little is known about GH, IGF-I, and IGFBP-3 serum levels in children with precocious puberty. Treatment of CPP by GnRH agonists has become the treatment of choice. However, the effect of long term...

  10. Human pregnancy serum contains at least two distinct proteolytic activities with the ability to degrade insulin-like growth factor binding protein-3.

    Science.gov (United States)

    Bang, P; Fielder, P J

    1997-09-01

    The presence of a proteolytic activity in sera from pregnant humans and rodents capable of degrading insulin-like growth factor binding protein-3 (IGFBP-3) has been known for some time. However, the identity of this activity has remained elusive. We have attempted to purify the IGFBP-3 protease activity from pregnant human serum (PHS) using the degradation of 125I-IGFBP-3 as a marker. Following ammonium sulfate precipitation of PHS and further enrichment of active fractions by ion-exchange, protein-A Sepharose, and size-exclusion chromatography, a protease of approximately 70-90 kDa was isolated and subjected to N-terminal analysis. The N-terminal sequence was consistent with plasminogen, a known fibrinolytic enzyme. To further characterize the IGFBP-3 protease activities in both PHS and nonpregnant human serum (NHS), aliquots of serum were first enriched by polyethylene glycol-precipitation and subjected to size-exclusion chromatography. The size-separated fractions were then incubated with 125I-IGFBP-3, and proteolytic activity was measured. PHS contained two separate proteases (>150 kDa and 70-90 kDa), whereas NHS contained only one (70-90 kDa) that had a inhibitor profile similar to plasmin. However, inhibitors of plasmin had no effect on the activity of the >150-kDa protease. Plasminogen activators (PAs) greatly increased the activity of the 70- to 90-kDa protease, but had little effect on the >150-kDa protease activity. Addition of PAs greatly increased the ability of NHS to proteolyze IGFBP-3. In contrast, the ability of plasminogen-depleted plasma to degrade 125I-IGFBP-3 was not affected by the addition of PAs. Both urokinase and tissue-type PA had the ability to proteolyze IGFBP-3 and were, in contrast to the >150-kDa protease activity, inhibited by the specific PA inhibitor D-PHE-PRO-ARG chloromethyl ketone. The present data suggest that sera has the ability to proteolyze IGFBP-3, and that this ability, as demonstrated by NHS, can be regulated by protease

  11. Serum free and total insulin-like growth factor-1, insulin-like growth factor binding protein-1 and insulin-like growth factor binding protein-3 levels in healthy elderly individuals - Relation to self-reported duality of health and disability

    NARCIS (Netherlands)

    Janssen, JAMJL; Stolk, RP; Pols, HAP; Grobbee, DE; Lamberts, SWJ

    1998-01-01

    Background: Little is known about the influence of the free insulin-like growth factor-I/insulin-like growth factor binding protein (IGF-I/IGFBP) system on the quality of health and on disability in the elderly population. Design: In a cross-sectional population based study of 218 healthy elderly

  12. Relationships between IGF-1 and IGFBP-1 and adiposity in obese African-American and Latino adolescents.

    Science.gov (United States)

    Alderete, Tanya L; Byrd-Williams, Courtney E; Toledo-Corral, Claudia M; Conti, David V; Weigensberg, Marc J; Goran, Michael I

    2011-05-01

    The purpose of this study was to examine interrelationships between insulin-like growth factor 1 (IGF-1), IGF binding proteins (IGFBPs), and adiposity in 49 African-American and 77 Latino obese adolescents (15.3 ± 0.1 and 15.4 ± 0.2 years; BMI: 33.0 ± 0.7 and 35.0 ± 1.0 kg/m(2), respectively). Immunoradiometric assays were used to measure IGF-1, IGFBP-1, and IGFBP-3. Total fat and soft lean tissue were measured by dual-energy X-ray absorptiometry and visceral adipose tissue (VAT), subcutaneous abdominal adipose tissue (SAAT), and hepatic fat fraction (HFF) were measured by magnetic resonance imaging. IGF-1 levels were 23.1% higher and IGFBP-1 were 40.4% higher in African Americans compared to Latinos after adjustment for total lean and total fat mass. IGF-1 and IGFBP-1 were inversely correlated with BMI, total fat mass, VAT, and HFF (r = -0.20 to -0.33, P < 0.05) while IGFBP-1 was inversely correlated with SAAT (r = -0.22, P < 0.05). These relationships did not differ by ethnicity, however, the relationship between IGF-1 and SAAT, as well as IGFBP-1 and HFF, differed by ethnicity. Predicted mean IGF-1 levels were 30.7% higher for African Americans at the 75th compared to 25th percentile of SAAT and only 11.7% higher for Latinos. Predicted mean IGFBP-1 levels were 158% higher for African Americans at the 25th compared to the 75th percentile of HFF while IGFBP-1 levels were 1.7% higher for Latinos at the 75th compared to the 25th percentile. These results demonstrate that the relationship between IGF-1 and SAAT as well as IGFBP-1 and HFF are different in African-American and Latino adolescents and may contribute to the higher IGF-1 levels in African-Americans.

  13. Insulin-like growth factor-1 and binding protein-3 in a 2-year soya intervention among premenopausal women.

    Science.gov (United States)

    Maskarinec, Gertraud; Takata, Yumie; Murphy, Suzanne P; Franke, Adrian A; Kaaks, Rudolph

    2005-09-01

    Soya foods may protect against the development of breast cancer. Insulin-like growth factor (IGF)-1 is under investigation as a possible link between nutrition and cancer. We examined the effect of soya foods on circulating IGF-1 and IGF binding protein (BP)-3 levels among 196 healthy premenopausal women in a 2-year randomised nutritional trial. The intervention group consumed two daily servings of soya foods including tofu, soya milk, soya nuts and soya protein powder (equivalent to 50 mg isoflavones and 5-22 g soya protein per serving); the controls maintained their regular diet. Five serum samples at baseline, 3, 6, 12, and 24 months were collected in the morning during the luteal phase and analysed for IGF-1 and IGFBP-3 by double-antibody ELISA. We applied mixed models to investigate the intervention effect and predictors of serum levels while considering the repeated measurement design. Adherence with the study regimen was high and dropout rates were acceptable. Randomisation resulted in similar mean IGF-1 and IGFBP-3 levels by group. We did not observe a significant intervention effect on IGF-1, IGFBP-3, and their molar ratio during the entire study period. However, urinary isoflavone excretion during the study period was positively associated with IGF-1 (P=0.04) and the IGF-1:IGFBP-3 ratio (P=0.06). The effect was consistent over time. Adding soya foods to the diet of premenopausal women does not appear to lower serum levels of IGF-1 and IGFBP-3; if anything, the greater protein intake from soya may lead to a small increase in IGF-1 serum levels.

  14. Association of sterol regulatory element binding protein 2 and insulin-like growth factor binding protein 3 genetic polymorphisms with avascular necrosis of the femoral head in the Chinese population

    Institute of Scientific and Technical Information of China (English)

    SONG Yang; DU Zhen-wu; LI Qiu-ju; ZHANG Gui-zhen; WANG Ling-ling; WU Ning; WANG Jin-cheng; GAO Zhong-li

    2012-01-01

    Background Sterol regulatory element binding protein(SREBP)-2 plays a key role in lipid homeostasis by stimulating gene expression of cholesterol biosynthetic pathways.The insulin-like growth factor binding protein(IGFBP)family regulates growth and metabolism,especially bone cell metabolism,and correlates with osteonecrosis.However,association of their gene polymorphisms with risk of avascular necrosis of the femoral head(ANFH)has rarely been reported.We determined whether SREBP-2 and IGFBP-3 gene polymorphisms were associated with increased ANFH risk in the Chinese population.Methods Two single nucleotide polymorphisms of SREBP2 gene,rs2267439 and rs2267443,and one of IGFBP-3 gene,rs2453839,were selected and genotyped in 49 ANFH patients and 42 control individuals by direct sequencing assay.Results The frequencies of rs2267439 TT and rs2267443 GA of SREBP2 and rs2453839 TT and CT of IGFBP-3 in the ANFH group showed increased and decreased tendencies(against normal control group),respectively.Interaction analysis of genes revealed that the frequency of carrying rs2267439 TT and rs2267443 GA genctypes of SREBF-2 in ANFH patients was significantly higher than in the control group(P<0.05).Association analysis between polymorphisms and clinical phenotype demonstrated that the disease course in ANFH patients with the rs2453839 TT genotype of IGFBP-3 was significantly shorter than that of CT+CC carriers(P<0.01).CT+CC genotype frequency in patients with stage Ⅲ/Ⅳ?bilateral hip lesions was significantly higher than in those with stage Ⅲ/Ⅳ?unilateral lesions and stage Ⅱ/Ⅲ?bilateral lesions(P<0.05-0.02).Conclusions Our results suggested that interaction of SREBP-2 gene polymorphisms and the relationship between the polymorphisms and clinical phenotype of IGFBP-3 were closely related to increased ANFH risk in the Chinese population.The most significant finding was that the CT+CC genotype carriers of IGFBP-3 rs2453839 were highly associated with the

  15. Serum IGF-1, IGFBP-3 levels and circulating tumor cells (CTCs) in early breast cancer patients.

    Science.gov (United States)

    Papadakis, Georgios Z; Mavroudis, Dimitrios; Georgoulias, Vasilios; Souglakos, John; Alegakis, Athanasios K; Samonis, George; Bagci, Ulas; Makrigiannakis, Antonis; Zoras, Odysseas

    2017-04-01

    Insulin-like growth factor (IGF)-axis is involved in human oncogenesis and metastasis development for various solid tumors including breast cancer. Aim of this study was to assess the association between IGF-1, IGF-binding protein-3 (IGFBP-3) serum levels and the presence of circulating tumor cells (CTCs) in the peripheral blood of women diagnosed with early breast cancer (EBC), before and after adjuvant chemotherapy. 171 patients with early-stage breast adenocarcinomas were retrospectively evaluated. Immunoradiometric (IRMA) assays were employed for the in-vitro determination of IGF-1 and IGFBP-3 serum levels in blood samples collected after surgical treatment and before initiation of adjuvant chemotherapy. CTCs' presence was assessed through detection of cytokeratin-19 (CK-19) mRNA transcripts using quantitative real time reverse transcription polymerase chain reaction (RT-PCR). IGF-1, IGFBP-3 serum levels were correlated with CTCs' presence before and after adjuvant chemotherapy as well as with tumor characteristics including tumor size, axillary lymph node status, oestrogen (ER)/progestorene (PR) and human epidermural growth factor receptor 2 (HER2) receptor status. Log-rank test was applied to investigate possible association between IGF-1, IGFBP-3 serum levels and disease-free interval (DFI) and overall survival (OS). Before initiation of adjuvant therapy IGF-1, IGFBP-3 serum levels were moderately associated (Spearman's rho=0.361, p<0.001) with each other, while presenting significant differences across age groups (all p values<0.05). IGF-1 serum levels did not correlate with the presence of CTCs before initiation (p=0.558) or after completion (p=0.474) of adjuvant chemotherapy. Similarly, IGFBP-3 serum levels did not show significant association with detectable CTCs either before (p=0.487) or after (p=0.134) completion of adjuvant chemotherapy. There was no statistically significant association between the clinical outcome of patients in terms of DFI, OS

  16. IGF-1, IGFBP-3, and nutritional factors in young black and white men: the CARDIA Male Hormone Study.

    Science.gov (United States)

    Colangelo, Laura A; Chiu, Brian C-H; Liu, Kiang; Kopp, Peter A; Gann, Peter H; Gapstur, Susan M

    2005-01-01

    Nutritional factors might play a role in regulating serum levels of insulin-like growth factors (IGFs), which are associated with some cancers. We examined the associations of nutritional factors with IGF-1 and IGF binding protein-3 (IGFBP-3). Serum IGF-1 and IGFBP-3 levels and dietary intake were measured in 459 black and 682 white male subjects of the Coronary Artery Risk Development in Young Adults study at the Year 7 (1992-1993) exam. Analysis of covariance and multivariable linear regression were used to assess associations of IGFs with dietary factors by race. IGF-1 was positively associated with magnesium in both black and white men (P = 0.008 and 0.05, respectively). Calcium was positively significantly related to IGF-1 in black men (P = 0.04) and marginally so in white men (P = 0.09). In black men, IGFBP-3 was positively associated with magnesium (P = 0.02), and one serving of milk per day was associated with an 8.23-ng/ml higher IGF-1 concentration (P = 0.05). Tests for interaction, however, revealed no differences between blacks and whites in the associations of nutrients with IGF-1 or IGFBP-3. In conclusion, the associations of dietary factors with serum IGF-1 and IGFBP-3 observed in our study corroborate those from other studies and generally do not differ between black and white men.

  17. Cervical length and phosphorilated insulin like growth factor binding protein-1 as the predictors of spontaneus preterm delivery in symptomatic women

    Directory of Open Access Journals (Sweden)

    Hadži-Lega Marija

    2014-07-01

    Full Text Available Objective: To assess the combined use of cervical length and cervical phosphorylated insulin-like growth factor binding protein-1 (phIGFBP-1 in the prediction of preterm delivery in symptomatic women in next 14 days. Methods: Cervical length was prospectively measured in 58 consecutive singleton pregnancies with intact membranes and regular contractions at 24-36 weeks, and phIGFBP-1 was assessed. Demographic data was evaluated(history of previous preterm delivery, history of spontaneous abortion, parity, BMI, maternal age, Orthodox or Muslims. Results: Values of all variables were evaluated (demographic data, cervical length and values ofphIGFBP-1 alone and in combination with cervical length of ≤ 15 mm and more than 15 mm. In women with cervical length less than 15 mm/ /phIGFPB-1 was positive in 30 patients(22 of them delivered in 14 days. In women with cervical length less than 15 mm/phIGFBP-1was positive in 9 of delivered pregnant women in 14 days. In women with cervical length less than 25 mm/phIGFBP-1was positive in 26 patients (2 of them delivered in 14 days. In patients with cervical length more than 25 mm/ph IGFBP-1 was positive in 4 patients (2 of them delivered in 14 days. With logistic regression we confirmed that with OR 0.117 and CI 95% (0.046-0.295 and p < 0.01 odds for preterm birth among patients with negative phIGFBP-1 is 0.117 lower than the odds for preterm birth among patients with positive test results. With same test for p = 0.009 (p < 0.01 we confirmed with OR and CI 95% (0.06 to 0.671 that cervical length less than 25 mm is good predictor of preterm delivery with symptomatic patients. Probability for delivery in the following 14 days with patients with positive phIGFBP-1 and cervical length ≤ 15 mm is 0.88 or probability for not delivering in those patients is 0.12. In 88% patients with positive phIGFBP-1 and cervical length ≤ 15 mm will deliver in the following 14 days. Conclusions: In symptomatic women phIGFBP-1

  18. CERVICAL LENGTH AND PHOSPHORILATED INSULIN LIKE GROWTH FACTOR BINDING PROTEIN-1 AS THE PREDICTORS OF SPONTANEUS PRETERM DELIVERY IN SYMPTOMATIC WOMEN

    Directory of Open Access Journals (Sweden)

    Hadzi-Lega Marija

    2014-07-01

    Full Text Available Objective: To assess the combined use of cervical length and cervical phosphorylated insulin-like growth factor binding protein-1 (phIGFBP-1 in the prediction of preterm delivery in symptomatic women in next 14 days. Methods: Cervical length was prospectively measured in 58 consecutive singleton pregnancies with intact membranes and regular contractions at 24–36 weeks, and phIGFBP-1 was assessed. Demographic data was evaluated (history of previous preterm delivery, history of spontaneous abortion, parity, BMI, maternal age, Orthodox or Muslims. Results: Values of all variables were evaluated (demographic data, cervical length and values of phIGFBP-1 alone and in combination with cervical length of ≤15 mm and more than 15 mm. In women with cervical length less than 15 mm/phIGFPB-1 was positive in 30 patients (22 of them delivered in 14 days. In women with cervical length less than 15 mm/phIGFBP-1 was positive in 9 of delivered pregnant women in 14 days. In women with cervical length less than 25 mm/phIGFBP-1was positive in 26 patients (2 of them delivered in 14 days. In patients with cervical length more than 25 mm/ph IGFBP-1 was positive in 4 patients (2 of them delivered in 14 days. With logistic regression we confirmed that with OR 0.117 and CI 95% (0.046–0.295 and p < 0.01 odds for preterm birth among patients with negative phIGFBP-1 is 0.117 lower than the odds for preterm birth among patients with positive test results. With same test for p = 0.009 (p < 0.01 we confirmed with OR and CI 95% (0.06 to 0.671 that cervical length less than 25 mm is good predictor of preterm delivery with symptomatic patients. Probability for delivery in the following 14 days with patients with positive phIGFBP-1and cervical length ≤ 15 mm is 0.88 or probability for not delivering in those patients is 0.12. In 88% patients with positive phIGFBP-1 and cervical length ≤ 15 mm will deliver in the following 14 days. Conclusions: In symptomatic women phIGFBP

  19. Changes in circulating level of IGF-I and IGF-binding protein-1 from the first to second trimester as predictors of preeclampsia

    DEFF Research Database (Denmark)

    Vatten, Lars J; Nilsen, Tom I L; Juul, Anders;

    2008-01-01

    OBJECTIVE: To assess whether circulating IGF-I and IGF-binding protein-1 (IGFBP-1) in the first and second trimester are associated with subsequent risk of preterm and term preeclampsia. METHODS: Nested case-control study within a cohort of 29 948 pregnant women. Cases were women, who later...... developed preeclampsia, and controls were randomly selected women, who did not develop preeclampsia. IGF-I and IGFBP-1 were measured with ELISA in maternal blood samples that were collected in the first and second trimesters. We assessed associations of IGF-I and IGFBP-1 concentrations with later...... development of preterm (before the 37th week of gestation) and term preeclampsia. RESULTS: An increase in IGF-I from the first to second trimester was associated with higher risk of preterm preeclampsia; the odds ratio (OR) for the highest compared with lowest quartile of increase was 4.9 (95% confidence...

  20. Insulin-like growth factors (IGFs) and IGF binding proteins in active Crohn's disease treated with omega-3 or omega-6 fatty acids and corticosteroids

    DEFF Research Database (Denmark)

    Eivindson, Martin; Grønbaek, Henning; Nielsen, Jens Nederby

    2005-01-01

    of the present study was to examine the effects of enteral nutrition, Impact Powder, as adjuvant therapy to corticosteroid treatment on changes in the GH/IGF-I axis in patients with Crohn's disease (CD). MATERIAL AND METHODS: The patients were randomized to 3-IP (omega-3-fatty acid (FA), 3 g/day) or 6-IP (omega......-6-FA, 9 g/day). Changes in total IGF-I (tIGF-I) and total IGF-II (tIGF-II), free IGF-I (fIGF-I), IGF binding proteins (IGFBP-1 and IGFBP-3), IGFBP-3 protease activity and insulin levels were examined in 31 patients with active CD (CDAI: 186-603) during treatment with prednisolone (40 mg for 1 week...

  1. Genotypes and haplotypes in the insulin-like growth factors, their receptors and binding proteins in relation to plasma metabolic levels and mammographic density

    Directory of Open Access Journals (Sweden)

    Chanock Stephen J

    2010-03-01

    Full Text Available Abstract Background Increased mammographic density is one of the strongest independent risk factors for breast cancer. It is believed that one third of breast cancers are derived from breasts with more than 50% density. Mammographic density is affected by age, BMI, parity, and genetic predisposition. It is also greatly influenced by hormonal and growth factor changes in a woman's life cycle, spanning from puberty through adult to menopause. Genetic variations in genes coding for hormones and growth factors involved in development of the breast are therefore of great interest. The associations between genetic polymorphisms in genes from the IGF pathway on mammographic density and circulating levels of IGF1, its binding protein IGFBP3, and their ratio in postmenopausal women are reported here. Methods Samples from 964 postmenopausal Norwegian women aged 55-71 years were collected as a part of the Tromsø Mammography and Breast Cancer Study. All samples were genotyped for 25 SNPs in IGF1, IGF2, IGF1R, IGF2R, IGFALS and IGFBP3 using Taqman (ABI. The main statistical analyses were conducted with the PROC HAPLOTYPE procedure within SAS/GENETICS™ (SAS 9.1.3. Results The haplotype analysis revealed six haploblocks within the studied genes. Of those, four had significant associations with circulating levels of IGF1 or IGFBP3 and/or mammographic density. One haplotype variant in the IGF1 gene was found to be associated with mammographic density. Within the IGF2 gene one haplotype variant was associated with levels of both IGF1 and IGFBP3. Two haplotype variants in the IGF2R were associated with the level of IGF1. Both variants of the IGFBP3 haplotype were associated with the IGFBP3 level and indicate regulation in cis. Conclusion Polymorphisms within the IGF1 gene and related genes were associated with plasma levels of IGF1, IGFBP3 and mammographic density in this study of postmenopausal women.

  2. EXPRESSION OF IGFBP-6 IN COLORECTAL CANCER: THE RELATION WITH INSULIN-LIKE GROWTH FACTOR RECEPTOR, ADIPONECTIN LEVEL AND ITS RECEPTORS

    Directory of Open Access Journals (Sweden)

    N. V. Yunusova

    2015-01-01

    Full Text Available The aim of the study was to investigate the expression of insulin-like growth factor binding protein 6 (IGFBP-6 in cancer tissues in relation with clinical and morphological parameters, IGF-IR expression, serum adiponectin level and its receptors (AdipoR1, AdipoR2 in patients with colorectal cancer.Material and Methods. The study included 31 patients with colorectal cancer (T2–4N0–2M0. Serum adiponectin level, AdipoR1 and AdipoR2 expression were evaluated with ELISA. IGF-IR expression was evaluated in tumor tissue by flow cytometry. IGFBP-6 expression was evaluated with Western blotting.Results. The dependence of IGFBP-6 expression, AdipoR1, AdipoR2 on tumor invasion and lymph nodes status were revealed. There is no association IGFBP-6 expression, AdipoR1 and AdipoR2 expression and serum adiponectin level with metabolic syndrome. The revealed positive relationships between IGFBP-6 expression and AdipoR1 expression, between IGFBP-6 expression and AdipoR2 expression, between IGF-IR and AdipoR1 expression show cross-talk between IGF-IR and adiponectin/AdipoR1 pathways in colorectal carcinomas.

  3. The prion protein binds thiamine.

    Science.gov (United States)

    Perez-Pineiro, Rolando; Bjorndahl, Trent C; Berjanskii, Mark V; Hau, David; Li, Li; Huang, Alan; Lee, Rose; Gibbs, Ebrima; Ladner, Carol; Dong, Ying Wei; Abera, Ashenafi; Cashman, Neil R; Wishart, David S

    2011-11-01

    Although highly conserved throughout evolution, the exact biological function of the prion protein is still unclear. In an effort to identify the potential biological functions of the prion protein we conducted a small-molecule screening assay using the Syrian hamster prion protein [shPrP(90-232)]. The screen was performed using a library of 149 water-soluble metabolites that are known to pass through the blood-brain barrier. Using a combination of 1D NMR, fluorescence quenching and surface plasmon resonance we identified thiamine (vitamin B1) as a specific prion ligand with a binding constant of ~60 μM. Subsequent studies showed that this interaction is evolutionarily conserved, with similar binding constants being seen for mouse, hamster and human prions. Various protein construct lengths, both with and without the unstructured N-terminal region in the presence and absence of copper, were examined. This indicates that the N-terminus has no influence on the protein's ability to interact with thiamine. In addition to thiamine, the more biologically abundant forms of vitamin B1 (thiamine monophosphate and thiamine diphosphate) were also found to bind the prion protein with similar affinity. Heteronuclear NMR experiments were used to determine thiamine's interaction site, which is located between helix 1 and the preceding loop. These data, in conjunction with computer-aided docking and molecular dynamics, were used to model the thiamine-binding pharmacophore and a comparison with other thiamine binding proteins was performed to reveal the common features of interaction.

  4. Molecular Characterization and Expression Analysis of Insulin-like Growth Factor-1 and Insulin-like Growth Factor Binding Protein-1 Genes in Qinghai-Tibet Plateau and Lowland

    Directory of Open Access Journals (Sweden)

    Ya-bing Chen

    2015-01-01

    Full Text Available Insulin-like growth factor-1 (IGF-1 and insulin-like growth factor binding protein-1 (IGFBP-1 play a pivotal role in regulating cellular hypoxic response. In this study, we cloned and characterized the genes encoding IGF-1 and IGFBP-1 to improve the current knowledge on their roles in highland Bos grunniens (Yak. We also compared their expression levels in the liver and kidney tissues between yaks and lowland cattle. We obtained full-length 465 bp IGF-1 and 792 bp IGFBP-1, encoding 154 amino acids (AA IGF-1, and 263 AA IGFBP-1 protein, respectively using reverse transcriptase-polyerase chain reaction (RT-PCR technology. Analysis of their corresponding amino acid sequences showed a high identity between B. grunniens and lowland mammals. Moreover, the two genes were proved to be widely distributed in the examined tissues through expression pattern analysis. Real-time PCR results revealed that IGF-1 expression was higher in the liver and kidney tissues in B. grunniens than in Bos taurus (p<0.05. The IGFBP-1 gene was expressed at a higher level in the liver (p<0.05 of B. taurus than B. grunniens, but it has a similar expression level in the kidneys of the two species. These results indicated that upregulated IGF-1 and downregulated IGFBP-1 are associated with hypoxia adaptive response in B. grunniens.

  5. Grafting of protein-protein binding sites

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A strategy for grafting protein-protein binding sites is described. Firstly, key interaction residues at the interface of ligand protein to be grafted are identified and suitable positions in scaffold protein for grafting these key residues are sought. Secondly, the scaffold proteins are superposed onto the ligand protein based on the corresponding Ca and Cb atoms. The complementarity between the scaffold protein and the receptor protein is evaluated and only matches with high score are accepted. The relative position between scaffold and receptor proteins is adjusted so that the interface has a reasonable packing density. Then the scaffold protein is mutated to corresponding residues in ligand protein at each candidate position. And the residues having bad steric contacts with the receptor proteins, or buried charged residues not involved in the formation of any salt bridge are mutated. Finally, the mutated scaffold protein in complex with receptor protein is co-minimized by Charmm. In addition, we deduce a scoring function to evaluate the affinity between mutated scaffold protein and receptor protein by statistical analysis of rigid binding data sets.

  6. Acquired resistance to EGFR tyrosine kinase inhibitors in cancer cells is mediated by loss of IGF-binding proteins

    Science.gov (United States)

    Guix, Marta; Faber, Anthony C.; Wang, Shizhen Emily; Olivares, Maria Graciela; Song, Youngchul; Qu, Sherman; Rinehart, Cammie; Seidel, Brenda; Yee, Douglas; Arteaga, Carlos L.; Engelman, Jeffrey A.

    2008-01-01

    Although some cancers are initially sensitive to EGFR tyrosine kinase inhibitors (TKIs), resistance invariably develops. We investigated mechanisms of acquired resistance to the EGFR TKI gefitinib by generating gefitinib-resistant (GR) A431 squamous cancer cells. In GR cells, gefitinib reduced phosphorylation of EGFR, ErbB-3, and Erk but not Akt. These cells also showed hyperphosphorylation of the IGFI receptor (IGFIR) and constitutive association of IRS-1 with PI3K. Inhibition of IGFIR signaling disrupted the association of IRS-1 with PI3K and restored the ability of gefitinib to downregulate PI3K/Akt signaling and to inhibit GR cell growth. Gene expression analyses revealed that GR cells exhibited markedly reduced IGF-binding protein 3 (IGFBP-3) and IGFBP-4 RNA. Addition of recombinant IGFBP-3 restored the ability of gefitinib to downregulate PI3K/Akt signaling and to inhibit cell growth. Finally, gefitinib treatment of mice with A431 xenografts in combination with an IGFIR-specific monoclonal antibody prevented tumor recurrence, whereas each drug given alone was unable to do so. These data suggest that loss of expression of IGFBPs in tumor cells treated with EGFR TKIs derepresses IGFIR signaling, which in turn mediates resistance to EGFR antagonists. Moreover, combined therapeutic inhibition of EGFR and IGFIR may abrogate this acquired mechanism of drug resistance and is thus worthy of prospective clinical investigation. PMID:18568074

  7. Effect of milk proteins on linear growth and IGF variables in overweight adolescents

    DEFF Research Database (Denmark)

    Larnkjær, Anni; Arnberg, Karina; Michaelsen, Kim F

    2014-01-01

    Milk may stimulate growth acting via insulin-like growth factor-I (IGF-I) secretion but the effect in adolescents is less examined. This study investigates the effect of milk proteins on linear growth, IGF-I, IGF binding protein-3 (IGFBP-3) and IGF-I/IGFBP-3 ratio in overweight adolescents....

  8. Effect of Low-Intensity Aerobic Exercise on Insulin-Like Growth Factor-I and Insulin-Like Growth Factor-Binding Proteins in Healthy Men

    Directory of Open Access Journals (Sweden)

    Yuichiro Nishida

    2010-01-01

    Full Text Available Increased concentrations of circulating insulin-like growth factor-I (IGF-I or IGF-I relative to IGF-binding proteins (IGFBPs are associated with increased risk of developing several forms of cancer. Conversely, exercise is linked with reduced risk. This study aims to investigate the effect of a low-intensity exercise program on circulating levels of IGF-I, IGFBP-1, and IGFBP-3, in previously sedentary males. Fourteen healthy men participated in cycle ergometer training at lactate threshold intensity for 60 min/day, 5 days/week for 6 weeks. After aerobic training, insulin sensitivity improved by 20%, while fasting insulin levels decreased by 13%. Simultaneously, low-intensity aerobic training decreased the circulating levels of IGF-I by 9%, while IGFBP-1 levels increased by 16%. An interesting finding was that higher pretraining level of IGF-I was associated with greater decline in IGF-I with training. Insulin-sensitizing low-intensity aerobic exercise is thus considered to be an effective method for downregulating IGF-I and upregulating IGFBP-1 levels.

  9. Nonparallel changes of growth hormone (GH) and insulin-like growth factor-I, insulin-like growth factor binding protein-3, and GH-binding protein, after craniospinal irradiation and chemotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Nivot, S.; Adan, L.; Souberbielle, J.; Rappaport, R.; Brauner, R.; Benelli, C.; Clot, J.P.; Saucet, C. [Hopital des Enfants-Malades, Paris (France); Zucker, J.M. [Institut Curie, Paris (France)

    1994-03-01

    The authors studied the GH-insulin-like growth factor-I (IGF-I) axis serially over 24-36 months in six patients with medulloblastoma who underwent surgical removal of the tumor followed by craniospinal irradiation therapy for 6 weeks and then chemotherapy for 42 weeks. Eighteen and 24 months after beginning irradiation there was a decline in the peak GH secretory response to acute stimulation with arginine/insulin hypoglycemia. Six months after irradiation and during chemotherapy there was a transient decline in IGF-I, IGF binding protein-3 (IGFBP-3), and GH-BP values (respective mean values of 56.1 {+-} 9.0 ng/mL, 1.1 {+-} 0.2 {mu}g/mL, and 7.6 {+-} 3.3% of radioactivity as compared to time 0 values: 139 {+-} 15 ng/mL, 2.2 {+-} 0.2 {mu}g/mL, and 20.0 {+-} 4.0%, P < 0.001), although provoked GH secretion was normal at this time. The IGF-I, IGFBP-3, and GH-BP returned to pretreatment ranges by 12-36 months after initiation of the study. There was also a decline in body mass index and serum protein values at 6 months after irradiation in ligand and immunoblot analysis there was a decline in IGFBP-3 and an abnormal electrophoretic mobility of IGFBP-2 that were both normalized at 36 months. In one patient they observed a high level of IGFBP-3 proteolysis at this time. This study demonstrates that before the decrease of GH secretion in patients receiving cranial irradiation there is a transient phase of GH insensitivity that may be characteristic of the acute therapeutic phase including the chemotherapy. This partial insensitivity may explain the early growth retardation observed in these patients. 28 refs., 4 figs., 1 tab.

  10. Serum total IGF-I, free IGF-I, and IGFBP-1 levels in an elderly population - Relation to cardiovascular risk factors and disease

    NARCIS (Netherlands)

    Janssen, JAMJL; Stolk, RP; Pols, HAP; Grobbee, DE; Lamberts, SWJ

    Recently, a method to measure free insulin-like growth factor-I (IGF-I) levels has been developed. Free IGF-I levels may have greater physiological and clinical relevance than total (bound and free) IGF-I. The associations between the circulating IGF-I/IGF binding protein (IGFBP) system and

  11. IGF-1 and IGFBP-1 in peripheral blood and decidua of early miscarriages with euploid embryos: comparison between women with and without PCOS.

    Science.gov (United States)

    Luo, Lu; Wang, Qiong; Chen, Minghui; Yuan, Guangqing; Wang, Zengyan; Zhou, Canquan

    2016-07-01

    This study aims to demonstrate the possible relationship between the insulin-like growth factor (IGF) system and early miscarriage in polycystic ovarian syndrome (PCOS) patients with euploid embryos. 40 pregnant women included. 9 had PCOS and miscarried; 20 had PCOS and a successful ongoing pregnancy; the remaining 11 women did not have PCOS and miscarried. An ultrasound scan was performed to prove clinical pregnancy and a blood sample was taken on day 55 ± 4 of gestation. Serum samples of IGF-1, insulin-like growth factor binding protein-1 (IGFBP-1), total testosterone, serum hormone binding protein (SHBG), leptin and soluble leptin receptor (sOb-R) were obtained. In miscarriages, samples of decidua were obtained during vaccum curettage. Embryonic chromosomes in all miscarriages were proven to be normal. The expression of IGF-1, IGFBP-1, leptin, long-form leptin receptor and androge sOb-R n receptor (AR) were examined in the decidua. We found that miscarried PCOS patients showed significantly increased free androgen index and free IGF index, as well as decreased SHBG and IGFBP-1 than other two groups in peripheral blood. In the decidua, miscarried PCOS patients showed significantly increased expression of IGF-1 and decreased IGFBP-1 when compared with non-PCOS. AR was not expressed in the decidua of either group. Our results suggest that early miscarriage is associated with increased IGF-1 and decreased IGFBP-1 in PCOS patients.

  12. BINDING ISOTHERMS SURFACTANT-PROTEINS

    Directory of Open Access Journals (Sweden)

    Elena Irina Moater

    2011-12-01

    Full Text Available The interactions between surfactants and proteins shows some similarities with interactions between surfactants and polymers, but the hydrophobic amphoteric nature of proteins and their secondary and tertiary structure components make them different from conventional polymer systems. Many studies from the past about surfactant - proteins bonding used the dialysis techniques. Other techniques used to determine the binding isotherm, included ultrafiltration, ultracentrifugation, potentiometry, ion-selective electrode method and surface tension. High affinity isotherms which are typical of an anionic surfactant - protein bonding, exhibit an initial increase steep followed by a slow growth region and then a vertical growth above a certain concentration. This isotherm is typical of ionic surfactant to protein binding. Often the high affinity initial bond appears at very low concentrations of surfactant and therefore in some protein-surfactant systems, the exact shape of the isotherm in this region may be missing. The surfactant - protein binding is influenced by a number of variables such as the nature and chain length of surfactant, pH, ionic strength, temperature, nature of this protein and additives.

  13. Immunoassays for the measurement of IGF-II, IGFBP-2 and -3, and ICTP as indirect biomarkers of recombinant human growth hormone misuse in sport. Values in selected population of athletes.

    Science.gov (United States)

    Abellan, Rosario; Ventura, Rosa; Palmi, Ilaria; di Carlo, Simonetta; Bacosi, Antonella; Bellver, Montse; Olive, Ramon; Pascual, Jose Antonio; Pacifici, Roberta; Segura, Jordi; Zuccaro, Piergiorgio; Pichini, Simona

    2008-11-04

    Insulin-like growth factor-II (IGF-II), insulin-like growth factor binding proteins (IGFBPs) -2 and -3 and C-terminal telopeptide of type I collagen (ICTP) have been proposed, among others, as indirect biomarkers of the recombinant human growth hormone misuse in sport. An extended intra- and inter-laboratory validation of commercially available immunoassays for biomarkers detection was performed. ELISA assays for total IGF-II, IGFBP-2 and IGFBP-3 (IGF-II/ELISA1: DSLabs, IGFBP-2/ELISA2: Biosource, and IGFBP-3/ELISA3: BioSource) and an EIA assay for ICTP (ICTP/EIA: Orion Diagnostica) were evaluated. The inter- and intra-laboratory precision values were acceptable for all evaluated assays (maximum imprecision of 30% and 66% were found only for the lowest quality control samples of IGF-II and IGFBP-3). Correct accuracy was obtained for all inter-laboratory immunoassays and for IGFBP-2 intra-laboratory immunoassay. The range of concentrations found in serum samples under investigation was always covered by the calibration curves of the studied immunoassays. However, 11% and 15% of the samples felt below the estimated LOQ for IGF-II and ICTP, respectively, in the zone where lower precision was obtained. Although the majority of evaluated assays showed an overall reliability not always suitable for antidoping control analysis, relatively high concordances between laboratory results were obtained for all assays. Evaluated immunoassays were used to measure serum concentrations of IGF-II, IGFBP-2 and -3 and ICTP in elite athletes of various sport disciplines at different moments of the training season; in recreational athletes at baseline conditions and finally in sedentary individuals. Serum IGF-II was statistically higher both in recreational and elite athletes compared to sedentary individuals. Elite athletes showed lower IGFBP-2 and higher IGFBP-3 concentration with respect to recreational athletes and sedentary people. Among elite athletes, serum IGFBP-3 (synchronized

  14. Serine 204 phosphorylation and O-β-GlcNAC interplay of IGFBP-6 as therapeutic indicator to regulate IGF-II functions in viral mediated hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    Sarwar Muhammad T

    2011-05-01

    Full Text Available Abstract Hepatocellular carcinoma is mainly associated with viral hepatitis B and C. Activation of cell growth stimulator IGF-II gene is observed in tumor formation especially in viral associated hepatocellular carcinoma. Elevated IGF-II levels are indicator of increased risk for cholangiocellular and hepatocellular carcinomas through over saturation of IGF-II binding capacities with IGF receptors leading to cellular dedifferentiation. In HCV, core protein is believed to trans-activate host IGF-II receptor through PKC pathway and the inhibition of tumor cell growth can be achieved by blocking IGF-II pathway either at transcriptional level or increasing its binding with IGFBPs (Insulin like growth factor proteins at C-terminal, so that it is not available in free form. IGFBP-6 is a specific inhibitor of IGF-II actions. Affinity of IGFBPs with IGFs is controlled by post-translational modifications. Phosphorylation of IGFBPs inhibits IGFs action on target cells while O-glycosylation prevents binding of IGFBP-6 to glycosaminoglycans and cell membranes and resulting in a 10-fold higher affinity for IGF-II. O-glycosylation and phosphorylation operate the functional expression of cellular proteins, this switching on and off the protein expression is difficult to monitor in vivo. By using neural network based prediction methods, we propose that alternate O-β-GlcNAc modification and phosphorylation on Ser 204 control the binding of IGFBP-6 with IGF-II. This information may be used for developing new therapies by regulating IGFBP-6 assembly with IGF-II to minimize the risk of viral associated hepatocellular carcinoma. We can conclude that during HCV/HBV infection, O-β-GlcNAc of IGFBP-6 at Ser 204 diminish their binding with IGF-II, increase IGF-II cellular expression and promote cancer progression which can lead to hepatocellular carcinoma. Furthermore, this site can be used for developing new therapies to control the IGF-II actions during viral

  15. Serine 204 phosphorylation and O-β-GlcNAC interplay of IGFBP-6 as therapeutic indicator to regulate IGF-II functions in viral mediated hepatocellular carcinoma.

    Science.gov (United States)

    Ahmad, Waqar; Shabbiri, Khadija; Ijaz, Bushra; Asad, Sultan; Nazar, Noreen; Nazar, Shazia; Fouzia, Kiran; Kausar, Humera; Gull, Sana; Sarwar, Muhammad T; Shahid, Imaran; Hassan, Sajida

    2011-05-08

    Hepatocellular carcinoma is mainly associated with viral hepatitis B and C. Activation of cell growth stimulator IGF-II gene is observed in tumor formation especially in viral associated hepatocellular carcinoma. Elevated IGF-II levels are indicator of increased risk for cholangiocellular and hepatocellular carcinomas through over saturation of IGF-II binding capacities with IGF receptors leading to cellular dedifferentiation. In HCV, core protein is believed to trans-activate host IGF-II receptor through PKC pathway and the inhibition of tumor cell growth can be achieved by blocking IGF-II pathway either at transcriptional level or increasing its binding with IGFBPs (Insulin like growth factor proteins) at C-terminal, so that it is not available in free form. IGFBP-6 is a specific inhibitor of IGF-II actions. Affinity of IGFBPs with IGFs is controlled by post-translational modifications. Phosphorylation of IGFBPs inhibits IGFs action on target cells while O-glycosylation prevents binding of IGFBP-6 to glycosaminoglycans and cell membranes and resulting in a 10-fold higher affinity for IGF-II. O-glycosylation and phosphorylation operate the functional expression of cellular proteins, this switching on and off the protein expression is difficult to monitor in vivo. By using neural network based prediction methods, we propose that alternate O-β-GlcNAc modification and phosphorylation on Ser 204 control the binding of IGFBP-6 with IGF-II. This information may be used for developing new therapies by regulating IGFBP-6 assembly with IGF-II to minimize the risk of viral associated hepatocellular carcinoma. We can conclude that during HCV/HBV infection, O-β-GlcNAc of IGFBP-6 at Ser 204 diminish their binding with IGF-II, increase IGF-II cellular expression and promote cancer progression which can lead to hepatocellular carcinoma. Furthermore, this site can be used for developing new therapies to control the IGF-II actions during viral infection to minimize the risk of

  16. Probing protein phosphatase substrate binding

    DEFF Research Database (Denmark)

    Højlys-Larsen, Kim B.; Sørensen, Kasper Kildegaard; Jensen, Knud Jørgen;

    2012-01-01

    Proteomics and high throughput analysis for systems biology can benefit significantly from solid-phase chemical tools for affinity pull-down of proteins from complex mixtures. Here we report the application of solid-phase synthesis of phosphopeptides for pull-down and analysis of the affinity...... around the phosphorylated residue are important for the binding affinity of ILKAP. We conclude that solid-phase affinity pull-down of proteins from complex mixtures can be applied in phosphoproteomics and systems biology....

  17. Serum IGFBP-2 and Risk of Atypical Hyperplasia of the Breast

    Directory of Open Access Journals (Sweden)

    Chelsea Catsburg

    2015-01-01

    Full Text Available Atypical hyperplasia of the breast (AH is associated with increased risk of subsequent invasive breast cancer, yet little is known about the etiology of AH. Insulin-like growth factor binding protein 2 (IGFBP-2 may contribute to the development of AH due to its proliferative effects on mammary tissue. We conducted a nested case-control study of postmenopausal women enrolled in Women’s Health Initiative-Clinical Trial. Cases were 275 women who developed incident AH during follow-up, individually (1 : 1 matched to controls. Levels of IGFBP-2 were determined from fasting serum collected at baseline. Multivariable conditional logistic regression models were used to estimate odds ratios for the association of IGFBP-2 with risk of AH. Serum IGFBP-2 was associated with a nonsignificant decrease in risk for AH, when comparing the highest quartile to lowest quartile (OR = 0.65; 95% CI = 0.32–1.31. This decrease in risk was most evident when analyses were restricted to nondiabetic, nonusers of hormone therapy (OR = 0.33, 95% CI = 0.13–0.86, ptrend = 0.06 and nondiabetic women who were overweight or obese (OR = 0.43, 95% CI = 0.18–1.03, ptrend = 0.05. Results from this study provide some support for an inverse association between serum IGFBP2 levels and risk of AH, particularly in nondiabetic women who are overweight or obese. Further studies are required to confirm these results.

  18. Megalin binds and mediates cellular internalization of folate binding protein

    DEFF Research Database (Denmark)

    Birn, Henrik; Zhai, Xiaoyue; Holm, Jan

    2005-01-01

    Folate is an essential vitamin involved in a number of biological processes. High affinity folate binding proteins (FBPs) exist both as glycosylphosphatidylinositol-linked, membrane associated folate binding proteins and as soluble FBPs in plasma and some secretory fluids such as milk, saliva...... to bind and mediate cellular uptake of FBP. Surface plasmon resonance analysis shows binding of bovine and human milk FBP to immobilized megalin, but not to low density lipoprotein receptor related protein. Binding of (125)I-labeled folate binding protein (FBP) to sections of kidney proximal tubule, known...

  19. Cellulose binding domain fusion proteins

    Science.gov (United States)

    Shoseyov, Oded; Shpiegl, Itai; Goldstein, Marc A.; Doi, Roy H.

    1998-01-01

    A cellulose binding domain (CBD) having a high affinity for crystalline cellulose and chitin is disclosed, along with methods for the molecular cloning and recombinant production thereof. Fusion products comprising the CBD and a second protein are likewise described. A wide range of applications are contemplated for both the CBD and the fusion products, including drug delivery, affinity separations, and diagnostic techniques.

  20. Insulin-like growth factors and insulin-like growth factor-binding proteins in relation to disease status and incidence of hypoglycaemia in patients with a gastrointestinal stromal tumour

    NARCIS (Netherlands)

    Rikhof, B.; van Doorn, J.; Suurmeijer, A. J. H.; Rautenberg, M. W.; Groenen, P. J. T. A.; Verdijk, M. A. J.; Jager, P. L.; de Jong, S.; Gietema, J. A.; van der Graaf, W. T. A.

    Patients and methods: Twenty-four patients were included. Plasma samples were collected before 1 week and median 5 months after start of treatment with imatinib, and levels of IGF-I, total IGF-II, pro-IGF-IIE[68-88], insulin-like growth factor-binding protein (IGFBP)-2, -3 and -6 were determined.

  1. Growth hormone (GH) provocative retesting of 108 young adults with childhood-onset GH deficiency and the diagnostic value of insulin-like growth factor I (IGF-I) and IGF-binding protein-3

    DEFF Research Database (Denmark)

    Juul, A; Kastrup, K W; Pedersen, S A;

    1997-01-01

    Serum levels of total insulin-like growth factor I (IGF-I) and IGF-binding protein-3 (IGFBP-3) reflect the endogenous GH secretion in healthy children and exhibit little diurnal variation, which makes them good diagnostic markers for screening of GH deficiency (GHD) in short children, although so...

  2. Prediction of the outcome of growth hormone provocative testing in short children by measurement of serum levels of insulin-like growth factor I and insulin-like growth factor binding protein 3

    DEFF Research Database (Denmark)

    Juul, A; Skakkebaek, N E

    1997-01-01

    Serum levels of insulin-like growth factor I (IGF-I) and insulin-like growth factor binding protein 3 (IGFBP-3) reflect the secretion of endogenous growth hormone (GH) in healthy children and exhibit little diurnal variation, which makes them potential candidates for screening of GH deficiency (G...

  3. ADAM 12, a disintegrin metalloprotease, interacts with insulin-like growth factor-binding protein-3

    DEFF Research Database (Denmark)

    Shi, Z; Xu, Wei; Loechel, F

    2000-01-01

    , as yet the pregnancy-specific protease, or proteases, have not been identified. We utilized a yeast two-hybrid assay and a human placental cDNA library to investigate IGFBP-3-interacting proteins. A disintegrin and metalloprotease-12 (ADAM 12), a member of a family of metalloprotease disintegrins...... that is highly expressed in placental tissue, was identified as interacting with IGFBP-3. This interaction involved the cysteine-rich domain of ADAM 12. Unlike other members of this family of disintegrin metalloproteases that are membrane proteins, ADAM 12 exists as an alternatively spliced soluble secreted...... medium on a heparin-Sepharose column also proteolyzed IGFBP-3. The degradation pattern was similar to that seen with pregnancy serum, and the presence of ADAM 12-S in serum during pregnancy was confirmed. The data suggest that ADAM 12-S has IGFBP-3 protease activity, and it may contribute to the IGFBP-3...

  4. Identification of Differentially Expressed IGFBP5-Related Genes in Breast Cancer Tumor Tissues Using cDNA Microarray Experiments

    OpenAIRE

    2015-01-01

    IGFBP5 is an important regulatory protein in breast cancer progression. We tried to identify differentially expressed genes (DEGs) between breast tumor tissues with IGFBP5 overexpression and their adjacent normal tissues. In this study, thirty-eight breast cancer and adjacent normal breast tissue samples were used to determine IGFBP5 expression by qPCR. cDNA microarrays were applied to the highest IGFBP5 overexpressed tumor samples compared to their adjacent normal breast tissue. Microarray a...

  5. Effects of IGFBP-2 on proliferation and differentiation in neural stem cell line C17.2

    Directory of Open Access Journals (Sweden)

    Deng Y

    2017-07-01

    Full Text Available Yujia Deng,1 Lei Wang,1,2 Lite Ge,1,3 Da Duan,1 Yi Zhuo,1 Ting Yuan,1 Weiping Yan,1 Peiqi Huang,1 Xiaohua Teng,1 Ming Lu1,3 1Department of Neurosurgery, The Second Affiliated Hospital of Hunan Normal University (163 Hospital of the People’s Liberation Army, Changsha, 2Department of Neurosurgery, Affiliated Haikou Hospital, Xiangya School of Central South University, Haikou, 3Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, People’s Republic of China Objective: Insulin-like growth factor binding protein-2 (IGFBP-2, a member of a highly conserved family of six insulin-like growth factor binding proteins (IGFBPs, can regulate several cellular processes through IGF-dependent or IGF-independent pathway. Recent studies have provided solid evidence for the importance to delineate that olfactory ensheathing cells (OEC-conditioned medium (OCM can not only facilitate the differentiation of neural stem cell line (C17.2 into neurons, but also promote the survival and proliferation. We have previously reported that IGFBP-2 was detected in OCM. This study is designed to investigate the roles of IGFBP-2 for the regulation of C17.2 differentiation and proliferation.Methods and results: IGFBP-2 was identified and upregulated in OCM to compare with astrocytes-conditioned medium by shotgun proteomics and semiquantitative proteomic analysis. In order to investigate whether exogenous IGFBP-2 could stimulate proliferation in C17.2 cells and differentiate it into glia or neuron, we used various concentrations of IGFBP-2 to induce C17.2 cells which were cultured in DMEM/F12. The results showed that exogenous IGFBP-2 can promote proliferation in C17.2 cells, but had little effect on differentiation. Interestingly, we also found that IGFBP-2 could induce C17.2 cells to differentiate into astrocytes, while inhibiting their differentiation into neurons in a dose

  6. [Inhibitory effect of inositol hexaphosphate on proliferation of LNCaP cells and its relation to IGFBP 3 expression].

    Science.gov (United States)

    Zhu, Hai-peng; Yun, Feng; Jiu, Tao

    2014-09-01

    To investigate the effect of inositol hexaphosphate (IP6) on proliferation of human prostate carcinoma LNCaP cells and its relation to insulin-like growth factors binding protein-3 (IGFBP-3) expression. The siRNA technology was used to silence the IGFBP-3 gene in LNCaP cells. LNCaP cells and IGFBP-3 gene silenced LNCaP cells were exposed to IP6 for 24 h. Cell viability was measured by MTT assay; cell cycle arrest and cell apoptosis were detected by flow cytometry. The expression levels of IGFBP-3 and Bcl-2 mRNA and protein were analyzed by real-time quantitative RT-PCR and Western blotting, respectively. The proliferation of LNCaP cells was be inhibited by IP6 in a dose dependent manner. After exposure to IP6 for 24 h, the cell viability in LNCaP cells and siRNA-treated LNCaP cells was 53.2%±11.6% and 82.3%±10.9%, respectively (PIP6,the apoptosis rate of LNCAP cells and siRNA-treated LNCAP cells was 40.48%±13.21% and 30.43%±10.65%, respectively (PIP6 treatment the percentage of G1 phase cells decreased to 48.66%±11.23% and G2 phase cells increased to 31.11%±9.68%. However, for siRNA treated LNCAP cells, the proportion of G1 phase cells was 58.25%±12.36% and G2 phase cells was 23.85%±12.45%. Higher expression of IGFBP-3 and lower expression of Bcl-2 in LNCaP cells treated with IP6 were found at both mRNA and protein levels. IP6 treatment enhanced IGFBP-3 mRNA expression by 2.21±0.15 folds. In the contrast, expression of Bcl-2 mRNA decreased by 0.69±0.03 folds. Meanwhile, after IGFBP- gene silence Bcl-2 expression was not decreased. IP6 can inhibit the proliferation of LNCaP cells, which may be associated with the changes of IGFBP-3 level through Bcl-2 expression.

  7. Insulin-like growth factor binding protein-1 levels are increased in patients with IgA nephropathy

    Energy Technology Data Exchange (ETDEWEB)

    Tokunaga, Koki [Department of Digestive and Life-Style Related Disease, Health Research Course, Human and Environmental Sciences, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8520 (Japan); Uto, Hirofumi, E-mail: hirouto@m2.kufm.kagoshima-u.ac.jp [Department of Digestive and Life-Style Related Disease, Health Research Course, Human and Environmental Sciences, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8520 (Japan); Takami, Yoichiro; Mera, Kumiko; Nishida, Chika; Yoshimine, Yozo; Fukumoto, Mayumi; Oku, Manei; Sogabe, Atsushi; Nosaki, Tsuyoshi; Moriuchi, Akihiro; Oketani, Makoto; Ido, Akio; Tsubouchi, Hirohito [Department of Digestive and Life-Style Related Disease, Health Research Course, Human and Environmental Sciences, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8520 (Japan)

    2010-08-20

    Research highlights: {yields} IGFBP-1 mRNA over express in kidneys obtained from mice model of IgA nephropathy. {yields} Serum IGFBP-1 levels are high in patients with IgA nephropathy. {yields} Serum IGFBP-1 levels correlate with renal function and the severity of renal injury. -- Abstract: The mechanisms underlying the pathogenesis of immunoglobulin A (IgA) nephropathy (IgAN) are not well understood. In this study, we examined gene expression profiles in kidneys obtained from mice with high serum IgA levels (HIGA mice), which exhibit features of human IgAN. Female inbred HIGA, established from the ddY line, were used in these experiments. Serum IgA levels, renal IgA deposition, mesangial proliferation, and glomerulosclerosis were increased in 32-week-old HIGA mice in comparison to ddY animals. By microarray analysis, five genes were observed to be increased by more than 2.5-fold in 32-week-old HIGA in comparison to 16-week-old HIGA; these same five genes were decreased more than 2.5-fold in 32-week-old ddY in comparison to 16-week-old ddY mice. Of these five genes, insulin-like growth factor (IGF) binding protein (IGFBP)-1 exhibited differential expression between these mouse lines, as confirmed by quantitative RT-PCR. In addition, serum IGFBP-1 levels were significantly higher in patients with IgAN than in healthy controls. In patients with IgAN, these levels correlated with measures of renal function, such as estimated glomerular filtration rate (eGFR), but not with sex, age, serum IgA, C3 levels, or IGF-1 levels. Pathologically, serum IGFBP-1 levels were significantly associated with the severity of renal injury, as assessed by mesangial cell proliferation and interstitial fibrosis. These results suggest that increased IGFBP-1 levels are associated with the severity of renal pathology in patients with IgAN.

  8. Human plasminogen binding protein tetranectin

    DEFF Research Database (Denmark)

    Kastrup, J S; Rasmussen, H; Nielsen, B B;

    1997-01-01

    The recombinant human plasminogen binding protein tetranectin (TN) and the C-type lectin CRD of this protein (TN3) have been crystallized. TN3 crystallizes in the tetragonal space group P4(2)2(1)2 with cell dimensions a = b = 64.0, c = 75.7 A and with one molecule per asymmetric unit. The crystals...... to at least 2.5 A. A full data set has been collected to 3.0 A. The asymmetric unit contains one monomer of TN. Molecular replacement solutions for TN3 and TN have been obtained using the structure of the C-type lectin CRD of rat mannose-binding protein as search model. The rhombohedral space group indicates...

  9. Bacterial oligopeptide-binding proteins.

    Science.gov (United States)

    Monnet, V

    2003-10-01

    This review focuses on bacterial oligopeptide-binding proteins, which form part of the oligopeptide transport system belonging to the ATP-binding cassette family of transporters. Depending on the bacterial species, these binding proteins (OppA) capture peptides ranging in size from 2 to 18 amino acids from the environment and pass them on to the other components of the oligopeptide transport system for internalisation. Bacteria have developed several strategies to produce these binding proteins, which are periplasmic in Gram- bacteria and membrane-anchored in Gram+, with a higher stoichiometry (probably necessary for efficient transport) than the other components in the transport system. The expression of OppA-encoding genes is clearly modulated by external factors, especially nitrogen compounds, but the mechanisms of regulation are not always clear. The best-understood roles played by OppAs are internalisation of peptides for nutrition and recycling of muropeptides. It has, however, recently become clear that OppAs are also involved in sensing the external medium via specific or non-specific peptides.

  10. Protein binding assay for hyaluronate

    Energy Technology Data Exchange (ETDEWEB)

    Lacy, B.E.; Underhill, C.B.

    1986-11-01

    A relatively quick and simple assay for hyaluronate was developed using the specific binding protein, hyaluronectin. The hyaluronectin was obtained by homogenizing the brains of Sprague-Dawley rats, and then centrifuging the homogenate. The resulting supernatant was used as a source of crude hyaluronectin. In the binding assay, the hyaluronectin was mixed with (/sup 3/H)hyaluronate, followed by an equal volume of saturated (NH/sub 4/)/sub 2/SO/sub 4/, which precipitated the hyaluronectin and any (/sup 3/H)hyaluronate associated with it, but left free (/sup 3/H)hyaluronate in solution. The mixture was then centrifuged, and the amount of bound (/sup 3/H)hyaluronate in the precipitate was determined. Using this assay, the authors found that hyaluronectin specifically bound hyaluronate, since other glycosaminoglycans failed to compete for the binding protein. In addition, the interaction between hyaluronectin and hyaluronate was of relatively high affinity, and the size of the hyaluronate did not appear to substantially alter the amount of binding. To determine the amount of hyaluronate in an unknown sample, they used a competition assay in which the binding of a set amount of (/sup 3/H)hyaluronate was blocked by the addition of unlabeled hyaluronate. By comparing the degree of competition of the unknown samples with that of known amounts of hyaluronate, it was possible to determine the amount of hyaluronate in the unknowns. They have found that this method is sensitive to 1 ..mu..g or less of hyaluronate, and is unaffected by the presence of proteins.

  11. Presence of Insulin-Like Growth Factor Binding Proteins Correlates With Tumor-Promoting Effects of Matrix Metalloproteinase 9 in Breast Cancer

    Directory of Open Access Journals (Sweden)

    Jae-Hyun Park

    2015-05-01

    Full Text Available The stroma of breast cancer can promote the disease’s progression, but whether its composition and functions are shared among different subtypes is poorly explored. We compared stromal components of a luminal [mouse mammary tumor virus (MMTV–Neu] and a triple-negative/basal-like [C3(1–Simian virus 40 large T antigen (Tag] genetically engineered breast cancer mouse model. The types of cytokines and their expression levels were very different in the two models, as was the extent of innate immune cell infiltration; however, both models showed infiltration of innate immune cells that expressed matrix metalloproteinase 9 (MMP9, an extracellular protease linked to the progression of many types of cancer. By intercrossing with Mmp9 null mice, we found that the absence of MMP9 delayed tumor onset in the C3(1-Tag model but had no effect on tumor onset in the MMTV-Neu model. We discovered that protein levels of insulin-like growth factor binding protein-1 (IGFBP-1, an MMP9 substrate, were increased in C3(1-Tag;Mmp9−/− compared to C3(1-Tag;Mmp9+/+ tumors. In contrast, IGFBP-1 protein expression was low in MMTV-Neu tumors regardless of Mmp9 status. IGFBP-1 binds and antagonizes IGFs, preventing them from activating their receptors to promote cell proliferation and survival. Tumors from C3(1-Tag;Mmp9−/− mice had reduced IGF-1 receptor phosphorylation, consistent with slower tumor onset. Finally, gene expression analysis of human breast tumors showed that high expression of IGFBP mRNA was strongly correlated with good prognosis but not when MMP9 mRNA was also highly expressed. In conclusion, MMP9 has different effects on breast cancer progression depending on whether IGFBPs are expressed.

  12. Association between serum insulin-like growth factor I or IGF-binding protein 3 and estimated glomerular filtration rate: results of a population-based sample

    Directory of Open Access Journals (Sweden)

    Dittmann Kathleen

    2012-12-01

    Full Text Available Abstract Background Insulin-like growth factor I (IGF-I, which is mostly carried in blood by IGF-binding protein 3 (IGFBP-3, was associated to the glomerular filtration rate and chronic kidney disease in a multiethnic study among US adults. The aim of the present study was to investigate whether serum IGF-I or IGFBP-3 are associated with estimated glomerular filtration rate (eGFR in a population-based study of Caucasian adults. Methods Data from 4028 subjects (2048 women aged 20 to 81 years from the Study of Health in Pomerania (SHIP were analyzed. Total serum IGF-I and IGFBP-3 concentrations were determined by chemiluminescence immunoassays and categorized into sex- and age-specific quartiles. Results After adjusting for age, waist circumference and type 2 diabetes mellitus, analysis of variance (ANOVA revealed inverse associations between serum IGF-I concentrations and eGFR in men as well as between serum IGFBP-3 concentrations and eGFR in men and women. Logistic regression analyses confirmed these findings and showed that high IGF-I or IGFBP-3 concentrations were associated with an increased risk of decreased eGFR (2 in men or women. These relations became stronger when lower eGFR cut-offs were used for the analyses. Conclusion Our data revealed associations of increased serum IGF-I concentrations and decreased eGFR in men but not in women and an association of increased serum IGFBP-3 concentrations and decreased eGFR in both sexes.

  13. Postprandial changes in plasma growth hormone, insulin, insulin-like growth factor (IGF)-I, and IGF-binding proteins in coho salmon fasted for varying periods.

    Science.gov (United States)

    Shimizu, Munetaka; Cooper, Kathleen A; Dickhoff, Walton W; Beckman, Brian R

    2009-08-01

    We examined postprandial changes in circulating growth hormone (GH), insulin, insulin-like growth factor (IGF)-I, and IGF-binding proteins (IGFBPs) in yearling coho salmon under different feeding regimes. Fish were initially fasted for 1 day, 1 wk, or 3 wk. Fasted fish were then fed, and blood was collected at 4-h intervals over 26 h. After the various periods of fasting, basal levels of insulin were relatively constant, whereas those of IGF-I, IGFBPs and GH changed in proportion to the duration of the fast. A single meal caused a rapid, large increase in the circulating insulin levels, but the degree of the increase was influenced by the fasting period. IGF-I showed a moderate increase 2 h after the meal but only in the regularly fed fish. Plasma levels of 41-kDa IGFBP were increased in all groups within 6 h after the single meal. The fasting period did not influence the response of 41-kDa IGFBP to the meal. IGFBP-1 and GH decreased after the meal to the same extent among groups regardless of the fasting period. The present study shows that insulin and IGF-I respond differently to long (weeks)- and short (hours)-term nutritional changes in salmon; insulin maintains its basal level but changes acutely in response to food intake, whereas IGF-I adjusts its basal levels to the long-term nutritional status and is less responsive to acute nutritional input. IGFBPs maintain their sensitivity to food intake, even after prolonged fasting, suggesting their critical role in the nutritional regulation of salmon growth.

  14. Serum measurements of testosterone, insulin-like growth factor 1, and insulin-like growth factor binding protein-3 in the diagnosis of prostate cancer among Korean men

    Institute of Scientific and Technical Information of China (English)

    Sung Kyu Hong; Byung Kyu Han; Jae Seung Jeong; Seong Jin Jeong; Ki Hyuk Moon; Seok Soo Byun; Sang Eun Lee

    2008-01-01

    Aim: To investigate the relationships of serum testosterone, insulin-like growth factor (IGF)-I and IGF-binding protein(IGFBP)-3 levels with prostate cancer risk and also with known prognostic parameters of prostate cancer in Korean men who received radical retropubic prostatectomy (RRP) for clinically-localized prostate cancer. Methods: Serum levels of total testosterone, free testosterone, IGF-1 and IGFBP-3 were determined in 592 patients who subsequently received prostate biopsy. Results were compared between patients who eventually received RRP for prostate cancer (n = 159) and those who were not diagnosed with prostate cancer from biopsy (control group, n = 433). Among the prostate cancer only patients, serum hormonal levels obtained were analyzed in relation to serum prostate specific antigen (PSA),pathological T stage and pathological Gleason score. Results: Prostate cancer patients and the control group demon-strated no significant differences regarding serum levels of total testosterone, free testosterone, IGF-1 and IGFBP-3 across the different age groups. Among the cancer only patients, no significant associations were observed for serum levels of total testosterone, free testosterone, IGF-1 and IGFBP-3 levels with pathological T stage, pathological Gleason score and preoperative PSA. Conclusion: Our data indicate that simple quantifications of serum testosterone and IGF-1 along with IGFBP-3 levels might not provide useful clinical information in the diagnosis of clinically localized prostate cancer in Korean men. Also, our results suggest that serum levels of testosterone, IGF-1 and IGFBP-3 might not be significantly associated with known prognostic factors of clinically localized prostate cancer in Korean men.

  15. Third trimester fetal growth and umbilical venous blood concentrations of IGF-1, IGFBP-1, and growth hormone at term.

    OpenAIRE

    Spencer, J. A.; T C Chang; J. Jones; Robson, S. C.; Preece, M. A.

    1995-01-01

    Insulin-like growth factor-1 (IGF-1), insulin-like growth factor binding protein-1 (IGFBP-1) and growth hormone (GH) concentrations were measured in umbilical venous blood after delivery of 78 term newborn infants. Three groups of pregnancies were prospectively identified during the third trimester, according to fetal size and subsequent fetal growth, assessed by repeated ultrasound scans. Fetal size was considered either appropriate for gestational age (AGA) or small for gestational age (SGA...

  16. Colocalization and identification of interaction sites between IGFBP-3 and GalNAc-T14.

    Science.gov (United States)

    Wu, Chen; Ma, Si-Si; Ge, Jian-Feng; Wang, Yuan-Yuan; Tian, Huan-Na; Liu, Xiao-Bo; Zhang, Bo; Liu, Fang-Ming; Zhang, Xiao-Kang; Li, Qin-Jian

    2012-05-15

    GalNAc-T14 was identified as a novel IGFBP-3 binding partner in previous studies. Here, we furtherly confirmed the interaction between them by confocal microscopy, and identified the binding domain and probable interaction sites of GalNAc-T14 with IGFBP-3. The result of subcellular localization indicated that GalNAc-T14 was distributed in the cytosol, whereas IGFBP-3 existed in the cytosol and nucleolus. Confocal analyses demonstrated that IGFBP-3 and GalNAc-T14 colocalized in the cytosol. The result from yeast two hybrid assay showed that the C terminus of GalNAc-T14 (408-552aa) was essential for the interaction between GalNAc-T14 and IGFBP-3, especially Tyr(408), Pro(409), and Glu(410) of GalNAc-T14 may play key roles in the interaction with IGFBP-3. In conclusion, these studies demonstrated that IGFBP-3 and GalNAc-T14 are colocalized in MCF-7 cells and confirmed the interaction between IGFBP-3 and GalNAc-T14. This interaction may play an important role in the functional regulation of IGFBP-3.

  17. Free and protein-bound insulin-like growth factor-I (IGF-I) and IGF-binding proteins in plasma of coho salmon, Oncorhynchus kisutch.

    Science.gov (United States)

    Shimizu, M; Swanson, P; Dickhoff, W W

    1999-09-01

    Total and free insulin-like growth factor-I (IGF-I) levels were quantified in plasma from growth hormone (GH)-treated and fasted coho salmon. Total IGF-I was measured by radioimmunoassay after acid-ethanol extraction and free IGF-I was separated from protein-bound IGF-I using ultrafiltration by centrifugation. Total and free IGF-I increased in plasma after GH treatment and decreased after fasting. The level of free IGF-I, however, was maintained at approximately 0.3% in both experiments. Unsaturated binding activity in plasma for IGF-I was assessed by incubation with (125)I-recombinant salmon IGF-I ((125)I-sIGF-I). Although there was no difference in binding activity between GH-treated and control fish, fasted fish showed higher binding activity than did fed fish, suggesting induction of unsaturated binding protein by fasting. IGF-binding protein (IGFBP) bands were observed in plasma of coho salmon by Western ligand blotting using (125)I-sIGF-I. A low-molecular-weight (22 kDa) band was clear in fasted fish but not detectable in fed fish. The IGFBP band, which has molecular weight similar to that of human IGFBP-3 (41 kDa), was more intense in GH-treated fish than in controls. The molecular distribution of IGF-I in plasma was examined by gel filtration under neutral conditions. Most IGF-I was eluted around 40 kDa. This result suggests that the major form of bound IGF-I in the circulation of coho salmon may be in a 40-kDa binary complex rather than in a 150-kDa ternary complex, as in mammals.

  18. Effects of cord serum insulin, IGF-II, IGFBP-2, IL-6 and cortisol concentrations on human birth weight and length: pilot study.

    Directory of Open Access Journals (Sweden)

    Arianna Smerieri

    Full Text Available BACKGROUND: The IGF system is recognised to be important for fetal growth. We previously described increased Insulin-like growth factor binding protein (IGFBP-2 cord serum concentrations in intra-uterine growth retardation (IUGR compared with appropriate for gestational age (AGA newborns, and a positive relationship of IGFBP-2 with Interleukin (IL-6. The role of cortisol in the fetus at birth is largely unknown, and interactions among peptides are their real effect on birth size is unknown. Furthermore, almost all studies have previously assayed peptides in serum several years after birth, and follow-up data from pregnancy are always lacking. This study aimed at establishing and clarifying the effect of cord serum insulin, IGF-II, IGFBP-2, cortisol and IL-6 concentrations on birth length and weight. METHODS: 23 IUGR and 37 AGA subjects were followed up from the beginning of pregnancy, and were of comparable gestational age. Insulin, IGF-II, IGFBP-2, cortisol and IL-6 concentrations were assayed in cord serum at birth, and a multiple regression model was designed and applied to assess which were the significant biochemical determinants of birth size. RESULTS: Insulin, cortisol, and IL-6, showed similar concentrations in IUGR and AGA as previously described, whereas IGF-II was lower, and IGFBP-2 increased in IUGR compared with AGA. IGF-II serum concentration was found to have a significant positive effect on both birth length (r:(:0.546; p: 0.001 and weight (r:0.679; p: 0.0001. IGFBP-2 had a near significant negative effect on both birth weight (r:-0.342; p: 0.05 and length (r:-0.372; p:0.03. CONCLUSION: IGF-II cord serum concentration was shown to have a significant positive effect on both birth length and weight, whereas IGFBP-2 had a significant negative effect. Insulin, cortisol, and IL-6 cord serum concentrations had no significant effect on birth size.

  19. Reductions in laminin beta2 mRNA translation are responsible for impaired IGFBP-5-mediated mesangial cell migration in the presence of high glucose.

    Science.gov (United States)

    Schaeffer, Valerie; Hansen, Kim M; Morris, David R; Abrass, Christine K

    2010-02-01

    Insulin-like growth factor binding protein-5 (IGFBP-5) mediates mesangial cell migration through activation of cdc42, and laminin421 binding to alpha(6)beta(1)-integrin (Berfield AK, Hansen KM, Abrass CK. Am J Physiol Cell Physiol 291: C589-C599, 2006). Because glomerular expression of laminin beta(2) is reduced in diabetic rats (Abrass CK, Spicer D, Berfield AK, St. John PL, Abrahamson DR. Am J Pathol 151: 1131-1140, 1997), we directly examined the effect of hyperglycemia on mesangial cell migration and laminin beta2 expression. Migration mediated by IGFBP-5 is impaired in the presence of 25 mM glucose. This reduction in migration was found to result from a loss in mesangial cell synthesis of laminin421, and IGFBP-5-induced migration could be restored by replacing laminin421. Additional studies showed that there was selective reduction in mRNA translation of laminin beta2 in the presence of high glucose. Preserved synthesis of laminin beta1 indicates that not all proteins are reduced by high glucose and confirms prior data showing that laminin411 cannot substitute for laminin421 in IGFBP-5-mediated migration. Given the importance of mesangial migration in the reparative response to diabetes-associated mesangiolysis, these findings provide new insights into abnormalities associated with diabetic nephropathy and the potential importance of differential control of protein translation in determination of alterations of protein expression.

  20. Transforming growth factor-beta1 stimulates the production of insulin-like growth factor-I and insulin-like growth factor-binding protein-3 in human bone marrow stromal osteoblast progenitors

    DEFF Research Database (Denmark)

    Kveiborg, Marie; Flyvbjerg, Allan; Eriksen, E F

    2001-01-01

    While transforming growth factor-beta1 (TGF-beta1) regulates proliferation and differentiation of human osteoblast precursor cells, the mechanisms underlying these effects are not known. Several hormones and locally acting growth factors regulate osteoblast functions through changes in the insulin......-like growth factors (IGFs) and IGF-binding proteins (IGFBPs). Thus, we studied the effects of TGF-beta1 on IGFs and IGFBPs in human marrow stromal (hMS) osteoblast precursor cells. TGF-beta1 increased the steady-state mRNA level of IGF-I up to 8.5+/-0.6-fold (P...

  1. Proteomics demonstration that normal breast epithelial cells can induce apoptosis of breast cancer cells through insulin-like growth factor-binding protein-3 and maspin.

    Science.gov (United States)

    Toillon, Robert-Alain; Lagadec, Chann; Page, Adeline; Chopin, Valérie; Sautière, Pierre-Eric; Ricort, Jean-Marc; Lemoine, Jérôme; Zhang, Ming; Hondermarck, Hubert; Le Bourhis, Xuefen

    2007-07-01

    Normal breast epithelial cells are known to exert an apoptotic effect on breast cancer cells, resulting in a potential paracrine inhibition of breast tumor development. In this study we purified and characterized the apoptosis-inducing factors secreted by normal breast epithelial cells. Conditioned medium was concentrated by ultrafiltration and separated on reverse phase Sep-Pak C18 and HPLC. The proapoptotic activity of eluted fractions was tested on MCF-7 breast cancer cells, and nano-LC-nano-ESI-MS/MS allowed the identification of insulin-like growth factor-binding protein-3 (IGFBP-3) and maspin as the proapoptotic factors produced by normal breast epithelial cells. Western blot analysis of conditioned media confirmed the specific secretion of IGFBP-3 and maspin by normal cells but not by breast cancer cells. Immunodepletion of IGFBP-3 and maspin completely abolished the normal cell-induced apoptosis of cancer cells, and recombinant proteins reproduced the effect of normal cell-conditioned medium on apoptosis of breast cancer cells. Together our results indicated that normal breast epithelial cells can induce apoptosis of breast cancer cells through IGFBP-3 and maspin. These findings provide a molecular hypothesis for the long observed inhibitory effect of normal surrounding cells on breast cancer development.

  2. Changes of insulin-like growth factor-Ⅱ and insulin-like growth factor binding protein-3 in cerebrospinal fluid of children with tuberculous meningitis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    BACKGROUND: Recent studies have found that insulin-like growth factors (IGFs) and insulin-like growth factor binding protein-3 (IGFBP-3) have stronger neurotrophic and neuroprotective effects. But whether their levels in cerebrospinal fluid could be used as an auxiliary indicator in differentially diagnosing tuberculous meningitis and viral encephalitis is not yet clear.OBJECTIVE: To explore the changes of insulin-like growth factor-Ⅱ (IGF-Ⅱ ) and IGFBP-3 in cerebrospinal fluid (CSF) of children with tuberculous meningitis and the significance of the changes.DESIGN: A non-randomized concurrent controlled study.SETTING: Department of Pediatric Internal Medicine, the First Affiliated Hospital of Xinxiang Medical College.PARTICIPANTS: Thirty children with tuberculous meningitis (14 males and 16 females) were selected from the Department of Pediatric Internal Medicine, the First Affiliated Hospital of Xinxiang Medical College from January 2005 to December 2006. Tuberculous meningitis was diagnosed according to their clinical manifestations, the history of close contact with tuberculosis, typical cerebrospinal fluid changes of tuberculous meningitis, positive tuberculosis antibody and effective antituberculosis treatment. There were 30 children (13 males and 17 females) with viral encephalitis, and viral encephalitis was diagnosed according to epidemiological history, clinical manifestations, conventional and biochemical changes of cerebrospinal fluid, and negative bacteriology judgment. Meanwhile, 30 children (13 males and 17 females) without infectious and central nervous system disease were selected as the control group. Informed consent was obtained from the parents of all the enrolled children.METHODS: ① The lumbar puncture operation was implemented immediately to obtain cerebrospinal fluid (3 mL). The contents of IGF-Ⅱ and IGFBP-3 were detected with immunoradiometric assay. The concentrations of glucose and protein in cerebrospinal fluid were determined

  3. “Associations of Serum Insulin-like Growth Factor (IGF-I) and IGFBP-3 Levels Biomarker-Calibrated Protein, Dairy, and Milk Intake in the Women's Health Initiative”1

    Science.gov (United States)

    Beasley, Jeannette M.; Gunter, Marc J.; LaCroix, Andrea Z.; Prentice, Ross L.; Neuhouser, Marian L.; Tinker, Lesley F.; Vitolins, Mara Z.; Strickler, Howard D.

    2014-01-01

    It is well-established that protein-energy malnutrition decreases serum insulin-like growth factor (IGF-I) levels, and supplementation of 30 grams of whey protein daily increased serum IGF-1 levels by 8% after 2 years in a clinical trial(1). Cohort studies provide the opportunity to assess associations between dietary protein intake and the IGF-axis under more typical eating conditions. We studied the associations of circulating IGF-axis protein levels (ELISA, Diagnostic Systems Laboratories) with total biomarker-calibrated protein intake, as well as dairy and milk intake, among postmenopausal women enrolled in the Women's Health Initiative (n=747). Analyses were conducted using multivariate linear regression models that adjusted for age, BMI, race/ethnicity, education, biomarker-calibrated energy, alcohol, smoking, physical activity, and hormone therapy use. There was a positive association between milk intake and free-IGF-1. A 3 serving increase in milk intake per day (~30 grams of protein) was associated with an estimated average 18.6% higher increase in free IGF-1 (95% CI 0.9% to 39.3%). Total IGF-I and IGFBP-3, however, were not associated with milk consumption, nor were there associations between biomarker-calibrated protein intake, biomarker-calibrated energy, and free IGF-I, total IGF-I, or IGFBP-3. This study of postmenopausal women is consistent with clinical trial data suggesting a specific relationship between milk consumption and serum IGF-I levels; albeit, in our dataset, this association was only statistically significant for free, but not total, IGF-I nor IGFBP-3. PMID:24094144

  4. Up-regulation of insulin-like growth factor-binding protein 3 by 5-fluorouracil (5-FU) leads to the potent anti-proliferative effect of androgen deprivation therapy combined with 5-FU in human prostate cancer cell lines.

    Science.gov (United States)

    Kawabata, Rumi; Oie, Shinji; Takahashi, Masayuki; Kanayama, Hiroomi; Oka, Toshinori; Itoh, Kohji

    2011-06-01

    In this study, we investigated the synergistic mechanism of anti-androgen and 5-fluorouracil (5-FU) combination therapy against castration-resistant prostate cancer (CRPC). Four prostate cancer cell lines, LNCaP, 22Rv1, DU145 and PC3, were examined for their growth dependency on androgens and the insulin-like growth factor 1 (IGF1). We assessed the expression changes of certain growth factor receptors and regulating proteins when treated with 5-FU, and found that 5-FU increased the expression of the IGF-binding protein 3 (IGFBP3). Furthermore, 5-FU inhibited the phosphorylation of Akt and p70 S6K, while the knockdown of IGFBP3 reduced the levels of poly (ADP-ribose) polymerase cleaved by 5-FU in PC3 cells. Therefore, the up-regulation of IGFBP3 by 5-FU not only inhibits cell growth by reducing the IGF1 signal but also induces apoptosis in PC3 cells. The synergistic effect of bicalutamide and 5-FU on 22Rv1 cells was reduced by IGFBP3 gene silencing using small-interfering RNA. These results suggest that the up-regulation of IGFBP3 induced by 5-FU plays an important role in the potent anti-tumor effect of 5-FU combined with anti-androgens on CRPC. Androgen-deprivation therapy combined with 5-FU could therefore be an appropriate therapy for CRPC patients.

  5. Expression and Characterization of Insulin-Like Growth Factor Binding Proteins (IGFBPs) and IGFBP-2 mRNA in the Developing Chicken Eye

    Science.gov (United States)

    1995-03-30

    nerves and blood vessels, and in the chicken, hyaline cartilage forms at certain positions between the choroid and sclera . The vitreous humor...types. In 1957, Salmon and Daughaday ascertained that in order for growth hormone to stimulate sulfate incorporation into cartilage , the presence of a...developing muscle and cartilage , while IGF-II mRNA is more abundant in mesodermal tissue such cartilage and blood vessels (BOndy et ai., 1990). as

  6. Actin binding proteins and spermiogenesis

    Science.gov (United States)

    Mruk, Dolores D

    2011-01-01

    Drebrin E, an actin-binding protein lacking intrinsic activity in the regulation of actin dynamics (e.g., polymerization, capping, nucleation, branching, cross-linking, bundling and severing), is known to recruit actin regulatory proteins to a specific cellular site. Herein, we critically evaluate recent findings in the field which illustrate that drebrin E works together with two other actin-binding proteins, namely Arp3 (actin-related protein 3, a component of the Arp2/3 complex that simultaneously controls actin nucleation for polymerization and branching of actin filaments) and Eps8 (epidermal growth factor receptor pathway substrate 8 that controls capping of the barbed ends of actin filaments, as well as actin filament bundling) to regulate the homeostasis of F-actin filament bundles at the ectoplasmic specialization (ES), a testis-specific atypical adherens junction (AJ) in the seminiferous epithelium. This is mediated by the strict temporal and spatial expression of these three actin-binding proteins at the apical and basal ES at the Sertoli cell-spermatid (step 8–19) and Sertoli-Sertoli cell interface, respectively, during the seminiferous epithelial cycle of spermatogenesis. In this Commentary, we put forth a possible model by which drebrin E may be acting as a platform upon which proteins (e.g., Arp3) that are needed to alter the conformation of actin filament bundles at the ES can be recruited to the site, thus facilitating changes in cell shape and cell position in the epithelium during spermiogenesis and spermiation. In short, drebrin E may be acting as a “logistic” distribution center to manage different regulatory proteins at the apical ES, thereby regulating the dynamics of actin filament bundles and modulating the plasticity of the apical ES. This would allow adhesion to be altered continuously throughout the epithelial cycle to accommodate spermatid movement in the seminiferous epithelium during spermiogenesis and spermiation. We also

  7. Polymorphism analysis of IGFBP-5 gene exon 1 in Tibet Mini-pig and Junmu No. 1 White pig.

    Science.gov (United States)

    Chen, A; Hao, L L; Fang, X B; Lu, K; Liu, S C; Zhang, Y L

    2014-03-12

    The genetic resources and the mechanism of miniaturization in the Tibet Mini-pig have not been comprehensively studied. Polymorphisms in genes related to the insulin-like growth factor (IGF) axis have been investigated for years, but few on the polymorphism of IGF-binding protein-5 (IGFBP-5) in the Tibetan pig. In this study, allele-specific polymerase chain reaction (AS-PCR) was used to analyze polymorphisms in exon 1 of the IGFBP-5 gene in two pig breeds, Tibet Mini-pigs and Junmu No. 1 White pigs. A BLAST analysis of the expressed sequence tags in the porcine IGFBP-5 gene revealed that exon 1 of this gene has two single nucleotide polymorphisms (SNPs), G188T and G503A. The AS-PCR results demonstrated that in both pig breeds examined, the TT, GT, and GG genotypes existed at the G188T locus, with GT as the most common genotype. At the G503A locus, GG, GA, and AA genotypes existed in Junmu No. 1 White pigs, with the GA genotype as the most frequently occurring. By contrast, at this locus, only the GA and AA genotypes were observed in the Tibetan pigs, and AA was more common than GA. There was a significant difference (P Tibet Mini-pigs than in Junmu No. 1 White pigs. The present study revealed SNPs in exon 1 of IGFBP-5 gene in the Tibet Mini-pig, possibly providing more understanding of the mechanism of miniaturization.

  8. Single Nucleotide Polymorphisms in IGFBP-2 Gene and Their Associations with Body Weight Traits on Jinghai Yellow Chicken

    Directory of Open Access Journals (Sweden)

    XH Zhao

    2015-12-01

    Full Text Available ABSTRACT Insulin-like growth factor binding protein-2 (IGFBP-2 regulates a broad spectrum of biological activities involved in growth, development, and differentiation. This study aimed at comparing polymorphisms in intron2 of the IGFBP-2 gene among four chicken breeds and at analyzing the associations between its genotypes and body weight in Jinghai Yellow chicken by using PCR-SSCP technique. For primer P2, three genotypes (AA, AB and BB were observed in the four chicken breeds. Gene sequencing revealed one insertion/deletion (the inserted/deleted TC after position 552bp in the intron 2 of IGFBP-2 gene. For primer P5, three genotypes were identified in Jinghai Yellow chickens, and named CC, CD and DD. Gene sequencing revealed two SNPs (C1107G, C1130T and one inserted/deleted GCCAGGT after 1115bp in the intron 2 of IGFBP-2 gene. The results of the linear model analysis showed that Jinghai Yellow chickens with AA genotype had significantly heavier body weight, at hatch and 12 weeks of age, than those of the AB genotype (p<0.05. The A allele had a positive effect on body weight. We speculate that mutations in intron 2 could be used as genetic markers for body weight in Jinghai Yellow chicken. This study provides valuable information for the protection of genetic resources and for breeding of Jinghai Yellow chicken.

  9. Insulin-like growth factor binding protein-3 is required for the regulation of rat oval cell proliferation and differentiation in the 2AAF/PHX model

    Directory of Open Access Journals (Sweden)

    Nicole C Steiger-Luther

    2010-02-01

    Full Text Available Nicole C Steiger-Luther1, Houda Darwiche1, Seh-Hoon Oh1, Jennifer M Williams1, Bryon E Petersen1,21Department of Pathology, Immunology and Laboratory Medicine, 2Program in Stem Cell Biology and Regenerative Medicine, College of Medicine, University of Florida, Gainesville, FL, USAAbstract: Oval cell-mediated liver regeneration is a highly complex process that involves the coordination of several signaling factors, chemokines and cytokines to allow for proper maintenance of the liver architecture. When hepatocyte proliferation is inhibited, an hepatic stem cell population, often referred to as “oval cells”, is activated to aid in liver regeneration. The function of insulin-like growth factor binding protein-3 (IGFBP-3 during this process of oval cell activation is of particular interest because it is produced in liver and has been shown to induce migration and differentiation of other stem cell populations both in vitro and in vivo. Additionally, IGFBP-3 production has been linked to the transforming growth factor-β (TGF-β superfamily, a pathway known to be induced during oval cell proliferation. In this study, we set out to determine whether IGFBP-3 plays a role in oval cell proliferation, migration and differentiation during this specific type of regeneration. Through activation of the oval cell-mediated liver regeneration in a rat model, we found that IGFBP-3 is elevated in the liver and serum of animals during peak days of oval cell activation and proliferation. Furthermore, in vitro assays found that WB-344 cells, a liver stem cell line similar to oval cells, were induced to migrate in the presence of IGFBP-3. When expression of IGFBP-3 was knocked down during oval cell activation in vivo, we found that oval cell proliferation was increased and observed the appearance of numerous atypical ductular structures, which were OV-6 and Ki67-positive. Finally, quantitative realtime PCR analysis of liver tissue from IGFBP-3 small interfering

  10. Herbal formula menoprogen alters insulin-like growth factor-1 and insulin-like growth factor binding protein-1 levels in the serum and ovaries of an aged female rat model of menopause.

    Science.gov (United States)

    Wei, Min; Zheng, Sheng Z; Lu, Ye; Liu, Daniel; Ma, Hong; Mahady, Gail B

    2015-10-01

    Menoprogen (MPG), a traditional Chinese medicine formula for menopause, improves menopausal symptoms; however, its mechanism remains unknown. Previous studies have shown that MPG is not directly estrogenic; thus, the goal of this study was to investigate the effects of MPG on insulin-like growth factor-1 (IGF-1) and insulin-like growth factor binding protein-1 (IGFBP-1) levels in an aged female rat model of menopause. In a six-arm study, 14-month-old female Sprague-Dawley rats (n = 8 per arm) were randomly divided into the following groups: untreated aged, 17β-estradiol-treated aged (estradiol [E2]), and three arms with increasing doses of MPG (162, 324, or 648 mg/kg/d). The sixth arm contained 4-month-old female Sprague-Dawley rats as a normal comparison group. Four weeks after MPG or E2 administration, animals were killed after blood draws, and ovarian tissues were excised. Levels of E2 and progesterone (P4) were determined by radioimmunoassay. Serum and ovarian tissue levels of IGF-1, IGFBP-1, and IGF-1 receptor were determined by enzyme-linked immunosorbent assay. Compared with the normal group, aged rats had significantly reduced serum levels of E2, P4, and IGF-1, and increased serum and ovarian tissue levels of IGFBP-1. MPG restored serum IGF-1 and IGFBP-1 levels and down-regulated ovarian levels of IGFBP-1, which were closely related to increases in E2 and P4 levels in aged rats. No significant differences in either IGF-1 or IGFBP-1 were observed between the three doses of MPG. MPG exerts a direct in vivo effect on aged female rats by positively regulating serum and ovarian IGF-1 and IGFBP-1 levels.

  11. Engineering RNA-binding proteins for biology

    OpenAIRE

    Chen,Yu; Varani, Gabriele

    2013-01-01

    RNA-binding proteins play essential roles in the regulation of gene expression. Many have modular structures and combine relatively few common domains in various arrangements to recognize RNA sequences and/or structures. Recent progress in engineering the specificity of the PUF class RNA-binding proteins has shown that RNA-binding domains may be combined with various effector or functional domains to regulate the metabolism of targeted RNAs. Designer RNA-binding proteins with tailored sequenc...

  12. IGF-I and IGF-binding proteins in articular exudates of children with post-traumatic knee damage and juvenile idiopathic arthritis.

    Science.gov (United States)

    Guszczyn, Tomasz; Rzeczycka, Justyna; Popko, Janusz

    2009-01-01

    IGF-I stimulates multiple functions of connective tissue cells and its activity is modulated by IGF-binding proteins (BPs). Some metalloproteinases are expected to modify IGF-I activity by digestion of IGF-BPs. It was decided to evaluate the concentration of IGF-I, IGF-BPs and the activity of gelatinases A and B in knee exudates of children with post-traumatic damage (PTD) and children with juvenile idiopathic arthritis (JIA) in comparison with those in the sera of the same patients. ELISA (for IGF-I assay), polyacrylamine gel electrophoresis following Western immunoblotting (for IGF-I and IGF-BPs expression), and zymography (for gelatinase detection) were used. The knee exudates, especially those taken from patients with JIA, contained large amounts of IGF-I. The exudates of PTD and JIA patients contained some forms of IGF-BP-1 of molecular weight lower than those occurring in serum. Low expression BP-3 and high activity of gelatinase B were detected in the JIA exudates. The high gelatinase activities in exudates imply joint tissue damage. The cellular response to damage of this kind is an increase in IGF-I production, which stimulates repair processes. High proteolytic activities of gelatinase B in JIA patients may lower the amount of BP-3, possibly causing a relative decrease of IGF-I concentration and impairing the reparation processes stimulated by IGF-I. Copyright 2009 S. Karger AG, Basel.

  13. Serum insulin-like growth factors I and II, insulin-like growth factor binding protein-3 and risk of breast cancer in the Japan Collaborative Cohort study.

    Science.gov (United States)

    Sakauchi, Fumio; Nojima, Masanori; Mori, Mitsuru; Wakai, Kenji; Suzuki, Sadao; Tamakoshi, Akiko; Ito, Yoshinori; Watanabe, Yoshiyuki; Inaba, Yutaka; Tajima, Kazuo; Nakachi, Kei

    2009-12-01

    The Japan Collaborative Cohort Study for Evaluation of Cancer Risk (JACC Study) was planned in the late 1980s as a large-scale cohort study of persons in various areas of Japan. In the present study, we conducted a nested case-control study and examined associations of breast cancer risk with serum levels of insulin-like growth factors I and II (IGF-I, IGF-II), as well as insulin-like growth factor binding protein-3 (IGFBP-3), among women who participated in the JACC Study and donated blood at the baseline. Sixty-three women who died or suffered from breast cancer were examined. Two or three controls were selected to match each case for age at recruitment and the study area. Controls were alive and not diagnosed as having breast cancer at the diagnosis date of the cases. Associations between the serum IGF-I, IGF-II, IGFBP-3 and breast cancer risk were evaluated using a conditional logistic regression model. In premenopausal Japanese women, IGF-I showed a marginal negative dose-dependent association with the breast cancer risk (trend P= 0.08), but any link disappeared on taking into account IGFBP-3 (trend P= 0.47), which was likely to be inversely associated with the risk. In postmenopausal women, IGFBP-3 showed a marginal dose-dependent association with the risk (trend P= 0.06). Further studies are needed to confirm these findings.

  14. Aberrant methylation of LINE-1, SLIT2, MAL and IGFBP7 in non-small cell lung cancer.

    Science.gov (United States)

    Suzuki, Makoto; Shiraishi, Kenji; Eguchi, Ayami; Ikeda, Koei; Mori, Takeshi; Yoshimoto, Kentaro; Ohba, Yasuomi; Yamada, Tatsuya; Ito, Takaaki; Baba, Yoshifumi; Baba, Hideo

    2013-04-01

    Genome-wide DNA hypomethylation and gene hypermethylation play important roles in instability and carcino-genesis. Methylation in long interspersed nucleotide element 1 (LINE-1) is a good indicator of the global DNA methylation level within a cell. Slit homolog 2 (SLIT2), myelin and lymphocyte protein gene (MAL) and insulin-like growth factor binding protein 7 (IGFBP7) are known to be hypermethylated in various malignancies. The aim of the present study was to assess the precise methylation levels of LINE-1, SLIT2, MAL and IGFBP7 in non-small cell lung cancer (NSCLC) using a pyrosequencing assay. Methylation of all regions was examined in 56 primary NSCLCs using a pyrosequencing assay. Changes in mRNA expression levels of SLIT2, MAL and IGFBP7 were measured before and after treatment with a demethylating agent. Methylation of these genes was also examined in 9 lung cancer cell lines using RT-PCR and a pyrosequencing assay. Frequencies of hypomethylation of LINE-1 and hypermethylation of SLIT2, MAL and IGFBP7, defined by predetermined cut off values, were 55, 64, 46 and 54% in NSCLCs, respectively and exhibited tumor-specific features. The hypermethylation of all genes was well correlated with changes in expression. The methylation level and frequency of MAL were significantly higher in smokers and in patients without EGFR mutations. Through accurate measurement of methylation levels using pyrosequencing, hypomethylation of LINE-1 and hypermethylation of SLIT2, MAL and IGFBP7 were frequently detected in NSCLCs and associated with various clinical features. Analysis of the methylation profiles of these genes may, therefore, provide novel opportunities for the therapy of NSCLCs.

  15. Aflatoxin exposure is inversely associated with IGF1 and IGFBP3 levels in vitro and in Kenyan schoolchildren.

    Science.gov (United States)

    Castelino, Jovita M; Routledge, Michael N; Wilson, Shona; Dunne, David W; Mwatha, Joseph K; Gachuhi, Kimani; Wild, Christopher P; Gong, Yun Y

    2015-03-01

    This study explores the relationship between aflatoxin and the insulin-like growth factor (IGF) axis and its potential effect on child growth. One hundred and ninety-nine Kenyan schoolchildren were studied for aflatoxin-albumin adduct (AF-alb), IGF1 and IGF-binding protein-3 (IGFBP3) levels using ELISA. AF-alb was inversely associated with IGF1 and IGFBP3 (p 198.5 pg/mg) were shorter than children in the lowest tertile (aflatoxin exposure on child height (p = 0.052). To further investigate this putative mechanistic pathway, HHL-16 liver cells (where HHL-16 is human hepatocyte line 16 cells) were treated with aflatoxin B1 (0.5, 5 and 20 μg/mL for 24-48 h). IGF1 and IGFBP3 gene expression measured by quantitative PCR and protein in culture media showed a significant down-regulation of IGF genes and reduced IGF protein levels. Aflatoxin treatment resulted in a significant decrease in IGF gene and protein expression in vitro. IGF protein levels were also lower in children with the highest levels of AFB-alb adducts. The data suggest that aflatoxin-induced changes in IGF protein levels could contribute to growth impairment where aflatoxin exposure is high. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Effects of IGF-binding protein 5 in dysregulating the shape of human hair.

    Science.gov (United States)

    Sriwiriyanont, Penkanok; Hachiya, Akira; Pickens, William L; Moriwaki, Shigeru; Kitahara, Takashi; Visscher, Marty O; Kitzmiller, William J; Bello, Alexander; Takema, Yoshinori; Kobinger, Gary P

    2011-02-01

    The hair follicle has a unique dynamic property to cyclically regenerate throughout life. Despite significant progress in hair structure and hair shape determination using animal models, the mechanisms controlling the architecture and the shape of the human hair remain largely unexplored. In this study, comparison of the genetic expression of several human genes, especially those involved in growth, development, and differentiation, between Caucasian curly hair and naturally straight hair was performed. Thereafter, analyses using human recombinant and lentiviral vector technologies were conducted to further dissect and elucidate a molecular mechanism that regulates hair growth and development, particularly in controlling the shape of the hair shaft. Overexpression of IGF-binding protein 5 (IGFBP-5) in the human hair xenografts obtained from straight- and curly-haired individuals was found to result in the decreased expression of several extracellular matrix proteins and disassembly of adhesional junctions, resulting in twisted hair shafts as well as an unusual deposition of hair cuticle that may be derived from the disturbance of normal proliferation and differentiation. This study provides evidence that IGFBP-5 has an effect on human hair shape, and that lentiviral transduction regimen can be used for functional analysis of genes involved in human hair morphogenesis.

  17. Subcutaneous administration of insulin-like growth factor (IGF)-II/IGF binding protein-2 complex stimulates bone formation and prevents loss of bone mineral density in a rat model of disuse osteoporosis

    Science.gov (United States)

    Conover, Cheryl A.; Johnstone, Edward W.; Turner, Russell T.; Evans, Glenda L.; John Ballard, F. John; Doran, Patrick M.; Khosla, Sundeep

    2002-01-01

    Elevated serum levels of insulin-like growth factor binding protein-2 (IGFBP-2) and a precursor form of IGF-II are associated with marked increases in bone formation and skeletal mass in patients with hepatitis C-associated osteosclerosis. In vitro studies indicate that IGF-II in complex with IGFBP-2 has high affinity for bone matrix and is able to stimulate osteoblast proliferation. The purpose of this study was to determine the ability of the IGF-II/IGFBP-2 complex to increase bone mass in vivo. Osteopenia of the femur was induced by unilateral sciatic neurectomy in rats. At the time of surgery, 14-day osmotic minipumps containing vehicle or 2 microg IGF-II+9 microg IGFBP-2/100g body weight/day were implanted subcutaneously in the neck. Bone mineral density (BMD) measurements were taken the day of surgery and 14 days later using a PIXImus small animal densitometer. Neurectomy of the right hindlimb resulted in a 9% decrease in right femur BMD (PBone histomorphometry indicated increases in endocortical and cancellous bone formation rates and in trabecular thickness. These results demonstrate that short-term administration of the IGF-II/IGFBP-2 complex can prevent loss of BMD associated with disuse osteoporosis and stimulate bone formation in adult rats. Furthermore, they provide proof of concept for a novel anabolic approach to increasing bone mass in humans with osteoporosis.

  18. Insulin-like growth factor-binding protein 2-driven glioma progression is prevented by blocking a clinically significant integrin, integrin-linked kinase, and NF-κB network

    Science.gov (United States)

    Holmes, Kristen M.; Annala, Matti; Chua, Corrine Y. X.; Dunlap, Sarah M.; Liu, Yuexin; Hugen, Niek; Moore, Lynette M.; Cogdell, David; Hu, Limei; Nykter, Matti; Hess, Kenneth; Fuller, Gregory N.; Zhang, Wei

    2012-01-01

    Insulin-like growth factor-binding protein 2 (IGFBP2) is increasingly recognized as a glioma oncogene, emerging as a target for therapeutic intervention. In this study, we used an integrative approach to characterizing the IGFBP2 network, combining transcriptional profiling of human glioma with validation in glial cells and the replication-competent ASLV long terminal repeat with a splice acceptor/tv-a glioma mouse system. We demonstrated that IGFBP2 expression is closely linked to genes in the integrin and integrin-linked kinase (ILK) pathways and that these genes are associated with prognosis. We further showed that IGFBP2 activates integrin β1 and downstream invasion pathways, requires ILK to induce cell motility, and activates NF-κB. Most significantly, the IGFBP2/integrin/ILK/NF-κB network functions as a physiologically active signaling pathway in vivo by driving glioma progression; interfering with any point in the pathway markedly inhibits progression. The results of this study reveal a signaling pathway that is both targetable and highly relevant to improving the survival of glioma patients. PMID:22345562

  19. IGF-1/IGFBP-1 increases blastocyst formation and total blastocyst cell number in mouse embryo culture and facilitates the establishment of a stem-cell line

    Directory of Open Access Journals (Sweden)

    Hsu Teng-Tsao

    2003-09-01

    Full Text Available Abstract Background Apoptosis occurs frequently for blastocysts cultured in vitro, where conditions are suboptimal to those found in the natural environment. Insulin-like growth factor-1 (IGF-1 plays an important role in preventing apoptosis in the early development of the embryo, as well as in the progressive regulation of organ development. We hypothesize that IGF-1 and its dephosphorylated binding protein (IGFBP-1 may be able to improve embryo culture with an associated reduced cell death, and that the resultant increase in the total cell number of the embryo could increase the chances of establishing an embryonic stem-cell line. Results In vivo fertilized zygotes were cultured in medium containing supplementary IGF-1, or IGFBP-1/IGF-1. The stages of the resultant embryos were evaluated at noon on day five post-hCG injection. The extent of apoptosis and necrosis was evaluated using Annexin V and propidium iodine staining under fluorescent microscopy. The establishment of embryonic stem-cell lines was performed using the hatching blastocysts that were cultured in the presence of IGF-1 or IGFBP-1/IGF-1. The results show that the rate of blastocyst formation in a tissue-culture system in the presence of IGF-1 was 88.7% and IGFBP-1/IGF-1 it was 94.6%, respectively, and that it was significantly greater than the figure for the control group (81.9%. IGFBP-1/IGF-1 also resulted in a higher hatching rate than was the case for the control group (68.8% vs. 48.6% respectively. IGF-1 also increased the number of Annexin V-free and propidium iodine-free blastocysts in culture (86.8% vs. 75.9% respectively. Total cell number of blastocyst in culture was increased by 18.9% for those examples cultured with dephosphorylated IGFBP-1/IGF-1. For subsequent stem-cell culture, the chances of the successful establishment of a stem-cell line was increased for the IGF-1 and IGFBP-1/IGF-1 groups (IGF-1 vs. IGFBP-1/IGF-1 vs. control: 45.8% vs. 59.6% vs. 27

  20. Nimotuzumab promotes radiosensitivity of EGFR-overexpression esophageal squamous cell carcinoma cells by upregulating IGFBP-3

    Directory of Open Access Journals (Sweden)

    Zhao Lei

    2012-12-01

    Full Text Available Abstract Background Epidermal growth factor receptor (EGFR is suggested to predict the radiosensitivity and/or prognosis of human esophageal squamous cell carcinoma (ESCC. The objective of this study was to investigate the efficacy of Nimotuzumab (an anti-EGFR monoclonal antibody on ESCC radiotherapy (RT and underlying mechanisms. Methods Nimotuzumab was administrated to 2 ESCC cell lines KYSE30 and TE-1 treated with RT. Cell growth, colony formation and apoptosis were used to measure anti-proliferation effects. The method of RNA interference was used to investigate the role of insulin-like growth factor binding protein-3 (IGFBP-3 in ESCC cells radiosensitivity treated with Nimotuzumab. In vivo effect of Nimotuzumab on ESCC radiotherapy was done using a mouse xenograft model. Results Nimotuzumab enhanced radiation response of KYSE30 cells (with high EGFR expression in vitro, as evidenced by increased radiation-inhibited cell growth and colony formation and radiation-mediated apoptosis. Mechanism study revealed that Nimotuzumab inhibited phosphorylated EGFR (p-EGFR induced by EGF in KYSE30 cells. In addition, knockdown of IGFBP-3 by short hairpin RNA significantly reduced KYSE30 cells radiosensitivity (PP>0.05. In KYSE30 cell xenografts, Nimotuzumab combined with radiation led to significant tumor growth delay, compared with that of radiation alone (P=0.029, and also with IGFBP-3 up-regulation in tumor tissue. Conclusions Nimotuzumab could enhance the RT effect of ESCC cells with a functional active EGFR pathway. In particular, the increased ESCC radiosensitivity by Nimotuzumab might be dependent on the up-regulation of IGFBP-3 through EGFR-dependent pathway.

  1. Associations of Insulin and IGFBP-3 with Lung Cancer Susceptibility in Current Smokers.

    Science.gov (United States)

    Ho, Gloria Y F; Zheng, Siqun L; Cushman, Mary; Perez-Soler, Roman; Kim, Mimi; Xue, Xiaonan; Wang, Tao; Schlecht, Nicolas F; Tinker, Lesley; Rohan, Thomas E; Wassertheil-Smoller, Sylvia; Wallace, Robert; Chen, Chu; Xu, Jianfeng; Yu, Herbert

    2016-07-01

    The epidermal growth factor receptor (EGFR) signaling network is involved in lung carcinogenesis. This study examined whether ligands that activate or suppress the EGFR signaling network were associated with lung cancer risk in ever smokers. A nested case-control study within the Women's Health Initiative assessed baseline plasma levels of insulin, insulin-like growth factor (IGF)-1, insulin-like growth factor binding protein (IGFBP)-3, interleukin (IL)-6, hepatocyte growth factor (HGF), and nerve growth factor (NGF) in 1143 ever-smoking lung cancer cases and 1143 controls. Leptin was measured as an adiposity biomarker. Conditional logistic regression was used in data analyses. Leptin was inversely associated with lung cancer risk (odds ratio [ORcontinuous] per Ln [pg/mL] = 0.85, 95% confidence interval [CI] = 0.74 to 0.98). After adjusting for adiposity and other risk factors, null associations were found for IL-6, HGF, and NGF. In current smokers, but not former smokers, high insulin levels were associated with increased lung cancer risk (OR for 4th quartile vs others [ORq4] = 2.06, 95% CI = 1.30 to 3.26) whereas IGFBP-3 had a linear inverse association (ORcontinuous per μg/mL = 0.64, 95% CI = 0.41 to 0.98). The insulin association was consistent across subgroups defined by body mass index and histological type, but the IGFBP-3 association was specific to small cell lung cancer. There was a modest positive association between IGF-1 and lung cancer risk in current smokers (ORq4 = 1.44, 95% CI = 0.90 to 2.29). Independent of obesity, high insulin levels but reduced levels of IGFBP-3 were associated with increased lung cancer risk in current smokers. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  2. Lead-Binding Proteins: A Review

    Directory of Open Access Journals (Sweden)

    Harvey C. Gonick

    2011-01-01

    Full Text Available Lead-binding proteins are a series of low molecular weight proteins, analogous to metallothionein, which segregate lead in a nontoxic form in several organs (kidney, brain, lung, liver, erythrocyte. Whether the lead-binding proteins in every organ are identical or different remains to be determined. In the erythrocyte, delta-aminolevulinic acid dehydratase (ALAD isoforms have commanded the greatest attention as proteins and enzymes that are both inhibitable and inducible by lead. ALAD-2, although it binds lead to a greater degree than ALAD-1, appears to bind lead in a less toxic form. What may be of greater significance is that a low molecular weight lead-binding protein, approximately 10 kDa, appears in the erythrocyte once blood lead exceeds 39 μg/dL and eventually surpasses the lead-binding capacity of ALAD. In brain and kidney of environmentally exposed humans and animals, a cytoplasmic lead-binding protein has been identified as thymosin β4, a 5 kDa protein. In kidney, but not brain, another lead-binding protein has been identified as acyl-CoA binding protein, a 9 kDa protein. Each of these proteins, when coincubated with liver ALAD and titrated with lead, diminishes the inhibition of ALAD by lead, verifying their ability to segregate lead in a nontoxic form.

  3. Advances on Plant Pathogenic Mycotoxin Binding Proteins

    Institute of Scientific and Technical Information of China (English)

    WANG Chao-hua; DONG Jin-gao

    2002-01-01

    Toxin-binding protein is one of the key subjects in plant pathogenic mycotoxin research. In this paper, new advances in toxin-binding proteins of 10 kinds of plant pathogenic mycotoxins belonging to Helminthosporium ,Alternaria ,Fusicoccum ,Verticillium were reviewed, especially the techniques and methods of toxin-binding proteins of HS-toxin, HV-toxin, HMT-toxin, HC-toxin. It was proposed that the isotope-labeling technique and immunological chemistry technique should be combined together in research of toxin-binding protein, which will be significant to study the molecular recognition mechanism between host and pathogenic fungus.

  4. Retinoid-binding proteins: similar protein architectures bind similar ligands via completely different ways.

    Directory of Open Access Journals (Sweden)

    Yu-Ru Zhang

    Full Text Available BACKGROUND: Retinoids are a class of compounds that are chemically related to vitamin A, which is an essential nutrient that plays a key role in vision, cell growth and differentiation. In vivo, retinoids must bind with specific proteins to perform their necessary functions. Plasma retinol-binding protein (RBP and epididymal retinoic acid binding protein (ERABP carry retinoids in bodily fluids, while cellular retinol-binding proteins (CRBPs and cellular retinoic acid-binding proteins (CRABPs carry retinoids within cells. Interestingly, although all of these transport proteins possess similar structures, the modes of binding for the different retinoid ligands with their carrier proteins are different. METHODOLOGY/PRINCIPAL FINDINGS: In this work, we analyzed the various retinoid transport mechanisms using structure and sequence comparisons, binding site analyses and molecular dynamics simulations. Our results show that in the same family of proteins and subcellular location, the orientation of a retinoid molecule within a binding protein is same, whereas when different families of proteins are considered, the orientation of the bound retinoid is completely different. In addition, none of the amino acid residues involved in ligand binding is conserved between the transport proteins. However, for each specific binding protein, the amino acids involved in the ligand binding are conserved. The results of this study allow us to propose a possible transport model for retinoids. CONCLUSIONS/SIGNIFICANCE: Our results reveal the differences in the binding modes between the different retinoid-binding proteins.

  5. Exercise-dependent IGF-I, IGFBPs, and type I collagen changes in human peritendinous connective tissue determined by microdialysis

    DEFF Research Database (Denmark)

    Olesen, Jens L; Heinemeier, Katja M; Gemmer, Carsten

    2007-01-01

    -like growth factor I (IGF-I) and its binding proteins (IGFBPs), which are known to stimulate collagen production in animal tendons, may regulate the translation of mechanical loading to collagen synthesis. Systemic and tissue levels of IGF-I, IGFBP, and type I collagen metabolism markers [procollagen I COOH......-terminal propeptide (PICP) and COOH-terminal telopeptide of type I collagen] were measured by microdialysis in peritendinous tissue of the human Achilles tendon in an exercise group (performing a 36-km run, n = 6) and a control group (no intervention, n = 6). An increase in local PICP concentration was seen in both...... and exercise groups after 48 h (P tissue in response to prolonged mechanical loading with part of the increase due to trauma from the sampling...

  6. Effect of Reinforcing Kidney Replenishing qi and Promoting Blood Circulation Recipe on the Expression of IGF-1, IGFBP-1 and IGFBP-3 in liver of the Fetal Rat with FGR%补肾益气活血方对胎儿生长受限胎鼠IGF-1、IGFBP-1及IGFBP-3表达的影响

    Institute of Scientific and Technical Information of China (English)

    王琪; 熊丽萍; 陶秀良

    2011-01-01

    Objective To investigate the effect of Bushen Yiqi Huoxue (Reinforcing Kidney Replenishing qi and Promoting Blood Circulation) Decoction on the expression of IGF - 1, IGFBP - 1 and IGFBP - 3 proteins in fetal liver of Fetal growth restriction ( FGR) rat. Methods The smoke inhalation rat model was created. Thirty two pregnant Sprague - Dawley rats were randomly dividedly into four groups: control group, FGR group, group of FGR treated with Bushen Yiqi Huoxue Decoction (Chinese medicine group), group of FGR treated with arginine ( arginine group). The expression of IGF - 1, IGFBP - 1 and IGFBP - 3 proteins in fetal liver were analyzed by immunohistochemis-try. Result Compared with FGR group, the expression of IGF - 1 and IGFBP -3 in fetal liver of Chinese medicine group increased significantly (P 0. 05). Conclusion The effect of Bushen Yiqi Huoxue Decoction on preventing and treating FGR may be attributed to regulating the expression of IGF - 1, IGFBP -1 and IGFBP -3.%目的 观察补肾益气活血方对胎儿生长受限胎鼠肝脏IGF-1、IGFBP-1、IGFBP-3表达的影响,探讨补肾益气活血方治疗FGR的作用机制.方法 采用被动吸烟法建立SD大鼠FGR模型,分为正常组、FGR组、补肾益气活血方治疗组(中药组)、精氨酸治疗组(精氨酸组).采用免疫组织化学方法检测胎鼠肝脏IGF-1、IGFBP-1、IGFBP-3的表达.结果 与FGR组比较,中药组胎鼠肝脏IGF-1、IGFBP-3的表达均明显升高(P<0.05),而IGFBP-1的表达明显降低(P<0.05),并且IGF-1的表达强度高于精氨酸组(P<0.05),各项指标与正常组比较差异无统计学意义(P>0.05).结论 补肾益气活血方可能通过调节IGF-Ⅰ、IGFBP-1、IGFBP-3的表达,从而促进胎儿在宫内的生长发育.

  7. Fractal aspects of calcium binding protein structures

    Energy Technology Data Exchange (ETDEWEB)

    Isvoran, Adriana [West University of Timisoara, Department of Chemistry, Pestalozzi 16, 300115 Timisoara (Romania)], E-mail: aisvoran@cbg.uvt.ro; Pitulice, Laura [West University of Timisoara, Department of Chemistry, Pestalozzi 16, 300115 Timisoara (Romania); Craescu, Constantin T. [INSERM U759/Institute Curie-Recherche, Centre Universitaire Paris-Sud, Batiment 112, 91405 Orsay (France); Chiriac, Adrian [West University of Timisoara, Department of Chemistry, Pestalozzi 16, 300115 Timisoara (Romania)

    2008-03-15

    The structures of EF-hand calcium binding proteins may be classified into two distinct groups: extended and compact structures. In this paper we studied 20 different structures of calcium binding proteins using the fractal analysis. Nine structures show extended shapes, one is semi-compact and the other 10 have compact shapes. Our study reveals different fractal characteristics for protein backbones belonging to different structural classes and these observations may be correlated to the physicochemical forces governing the protein folding.

  8. Computational Prediction of RNA-Binding Proteins and Binding Sites.

    Science.gov (United States)

    Si, Jingna; Cui, Jing; Cheng, Jin; Wu, Rongling

    2015-01-01

    Proteins and RNA interaction have vital roles in many cellular processes such as protein synthesis, sequence encoding, RNA transfer, and gene regulation at the transcriptional and post-transcriptional levels. Approximately 6%-8% of all proteins are RNA-binding proteins (RBPs). Distinguishing these RBPs or their binding residues is a major aim of structural biology. Previously, a number of experimental methods were developed for the determination of protein-RNA interactions. However, these experimental methods are expensive, time-consuming, and labor-intensive. Alternatively, researchers have developed many computational approaches to predict RBPs and protein-RNA binding sites, by combining various machine learning methods and abundant sequence and/or structural features. There are three kinds of computational approaches, which are prediction from protein sequence, prediction from protein structure, and protein-RNA docking. In this paper, we review all existing studies of predictions of RNA-binding sites and RBPs and complexes, including data sets used in different approaches, sequence and structural features used in several predictors, prediction method classifications, performance comparisons, evaluation methods, and future directions.

  9. Role of IGFBP7 in Diabetic Nephropathy: TGF-β1 Induces IGFBP7 via Smad2/4 in Human Renal Proximal Tubular Epithelial Cells.

    Directory of Open Access Journals (Sweden)

    Jun Watanabe

    Full Text Available Tubular injury is one of the important determinants of progressive renal failure in diabetic nephropathy (DN, and TGF-β1 has been implicated in the pathogenesis of tubulointerstitial disease that characterizes proteinuric renal disease. The aim of this study was to identify novel therapeutic target molecules that play a role in the tubule damage of DN. We used an LC-MS/MS-based proteomic technique and human renal proximal epithelial cells (HRPTECs. Urine samples from Japanese patients with type 2 diabetes (n = 46 were used to quantify the candidate protein. Several proteins in HRPTECs in cultured media were observed to be driven by TGF-β1, one of which was 33-kDa IGFBP7, which is a member of IGFBP family. TGF-β1 up-regulated the expressions of IGFBP7 mRNA and protein in a dose- and time-dependent fashion via Smad2 and 4, but not MAPK pathways in HRPTECs. In addition, the knockdown of IGFBP7 restored the TGF-β1-induced epithelial to mesenchymal transition (EMT. In the immunohistochemical analysis, IGFBP7 was localized to the cytoplasm of tubular cells but not that of glomerular cells in diabetic kidney. Urinary IGFBP7 levels were significantly higher in the patients with macroalbuminuria and were correlated with age (r = 0.308, p = 0.037, eGFR (r = -0.376, p = 0.01, urinary β2-microglobulin (r = 0.385, p = 0.008, and urinary N-acetyl-beta-D-glucosaminidase (NAG (r = 0.502, p = 0.000. A multivariate regression analysis identified urinary NAG and age as determinants associated with urinary IGFBP7 levels. In conclusion, our data suggest that TGF-β1 enhances IGFBP7 via Smad2/4 pathways, and that IGFBP7 might be involved in the TGF-β1-induced tubular injury in DN.

  10. MiR-204-5p suppresses cell proliferation by inhibiting IGFBP5 in papillary thyroid carcinoma.

    Science.gov (United States)

    Liu, Lianyong; Wang, Jingnan; Li, Xiangqi; Ma, Junhua; Shi, Chao; Zhu, Hongling; Xi, Qian; Zhang, Jichen; Zhao, Xuemei; Gu, Mingjun

    2015-02-20

    microRNAs (miRNAs) are frequently dysregulated in human malignancies. It was recently shown that miR-204-5p is downregulated in papillary thyroid carcinoma (PTC); however, the functional significance of this observation is not known. This study investigated the role of miR-204-5p in PTC. Overexpressing miR-204-5p suppressed PTC cell proliferation and induced cell cycle arrest and apoptosis. The results of a luciferase reporter assay showed that miR-204-5p can directly bind to the 3' untranslated region (UTR) of insulin-like growth factor-binding protein 5 (IGFBP5) mRNA, and IGFBP5 overexpression partially reversed the growth-inhibitory effects of miR-204-5p. These results indicate that miR-204-5p acts as a tumor suppressor in PTC by regulating IGFBP5 expression and that miR-204-5p can potentially serve as an antitumorigenic agent in the treatment of PTC.

  11. EFFECTS OF EARLY NUTRITION INTERVENTION ON IGF1, IGFBP3, INTESTINAL DEVELOPMENT, AND CATCH-UP GROWTH OF INTRAUTERINE GROWTH RETARDATION RATS

    Institute of Scientific and Technical Information of China (English)

    Xiao-shan Qiu; Ting-ting Huang; Hui-ying Deng; Zhen-yu Shen; Zhi-yong Ke; Kai-yong Mei; Feng Lai

    2004-01-01

    Objective To investigate the effects of early nutritional intervention on the serum insulin-like growth factor-1 (IGF1),insulin-like growth factor binding protein 3 (IGFBP3), intestinal development, and catch-up growth of intrauterine growth retardation (IUGR) rats by giving the IUGR new born rats different protein level diet.Methods IUGR rat model was built by starvation of pregnant female rats. Twenty-four IUGR pups and 8 normal pups were divided randomly into 4 groups: normal control group (C group); IUGR control group(S group), IUGR low-protein diet group (SL group), and IUGR high-protein diet group (SH group). Detected the serum IGF1, IGFBP3, body weight,body length, intestinal weight length, intestinal villi height (VH), crypt depth (CD), villi absorbing area (VSA), mucous thickness (MT), and disaccharidase at the 4th week.Results (1) The SH group showed the fastest catch-up growth, serum IGF1, IGFBP3, VH, and VSA were significantly higher than those of normal control group and IUGR control group. The intestinal weight and length, and the activities of lactase and saccharase of the SH group also reached the normal control group level. (2) The SL group kept on small size, the serum IGF1, IGFBP3, and most of intestinal histological indexes were all significantly lower than other groups. (3) IGF-1, IGFBP3 were positively correlated to intestinal VH, VSA, saccharase, body weight and length.Conclusions The serum IGF1 was a sensitive index to the catch-up growth. The early nutritional intervention of highprotein diet after birth is helpful for the catch-up growth of IUGR through promoting the intestinal development and the absorption of nutrition.

  12. Computational Prediction of RNA-Binding Proteins and Binding Sites

    Directory of Open Access Journals (Sweden)

    Jingna Si

    2015-11-01

    Full Text Available Proteins and RNA interaction have vital roles in many cellular processes such as protein synthesis, sequence encoding, RNA transfer, and gene regulation at the transcriptional and post-transcriptional levels. Approximately 6%–8% of all proteins are RNA-binding proteins (RBPs. Distinguishing these RBPs or their binding residues is a major aim of structural biology. Previously, a number of experimental methods were developed for the determination of protein–RNA interactions. However, these experimental methods are expensive, time-consuming, and labor-intensive. Alternatively, researchers have developed many computational approaches to predict RBPs and protein–RNA binding sites, by combining various machine learning methods and abundant sequence and/or structural features. There are three kinds of computational approaches, which are prediction from protein sequence, prediction from protein structure, and protein-RNA docking. In this paper, we review all existing studies of predictions of RNA-binding sites and RBPs and complexes, including data sets used in different approaches, sequence and structural features used in several predictors, prediction method classifications, performance comparisons, evaluation methods, and future directions.

  13. Mercury-binding proteins of Mytilus edulis

    Energy Technology Data Exchange (ETDEWEB)

    Roesijadi, G.; Morris, J. E.; Calabrese, A.

    1981-11-01

    Mytilus edulis possesses low molecular weight, mercury-binding proteins. The predominant protein isolated from gill tissue is enriched in cysteinyl residues (8%) and possesses an amino acid composition similar to cadmium-binding proteins of mussels and oysters. Continuous exposure of mussels to 5 ..mu..g/l mercury results in spillover of mercury from these proteins to high molecular weight proteins. Antibodies to these proteins have been isolated, and development of immunoassays is presently underway. Preliminary studies to determine whether exposure of adult mussels to mercury will result in induction of mercury-binding proteins in offspring suggest that such proteins occur in larvae although additional studies are indicated for a conclusive demonstration.

  14. Predicting where small molecules bind at protein-protein interfaces.

    Directory of Open Access Journals (Sweden)

    Peter Walter

    Full Text Available Small molecules that bind at protein-protein interfaces may either block or stabilize protein-protein interactions in cells. Thus, some of these binding interfaces may turn into prospective targets for drug design. Here, we collected 175 pairs of protein-protein (PP complexes and protein-ligand (PL complexes with known three-dimensional structures for which (1 one protein from the PP complex shares at least 40% sequence identity with the protein from the PL complex, and (2 the interface regions of these proteins overlap at least partially with each other. We found that those residues of the interfaces that may bind the other protein as well as the small molecule are evolutionary more conserved on average, have a higher tendency of being located in pockets and expose a smaller fraction of their surface area to the solvent than the remaining protein-protein interface region. Based on these findings we derived a statistical classifier that predicts patches at binding interfaces that have a higher tendency to bind small molecules. We applied this new prediction method to more than 10,000 interfaces from the protein data bank. For several complexes related to apoptosis the predicted binding patches were in direct contact to co-crystallized small molecules.

  15. Changes in IGF-I and its Binding Proteins Are Associated with Diabetes in Older Adults

    Science.gov (United States)

    Aneke, Chino S.; Parrinello, Christina M.; Rajpathak, Swapnil N.; Rohan, Thomas E.; Strotmeyer, Elsa S.; Kritchevsky, Stephen B.; Psaty, Bruce M.; Bůžková, Petra; Kizer, Jorge R.; Newman, Anne B.; Strickler, Howard D.; Kaplan, Robert C.

    2015-01-01

    Objectives Little is known about long-term changes in insulin-like growth Factor (IGF) proteins and glycemic status. We hypothesized that changes in IGF proteins are exaggerated in participants with type 2 diabetes or worsening glycemia versus those that remain normoglycemic over a 9-year follow-up period. Design Retrospective analysis of cohort study. Setting Participants were recruited from four States: North Carolina, California, Maryland and Pennsylvania. Participants 897 participants enrolled in CHS All Stars, a cohort study of community dwelling adults aged ≥65 years. Measurements Plasma IGF-I, IGFBP-1, and IGFBP-3 levels were assessed and ADA cut-points for IGT, IFG, and diabetes were used to classify participants at baseline (1996–1997) and follow-up (2005–2006). Results At baseline, mean age was 76.3 years (± 3.6) and 18.5% had diabetes. Individuals with IFG alone and IGT+IFG had the highest levels of IGF-I and lowest levels of IGFBP-1, compared to individuals with normoglycemia or diabetes. The greatest percent change in IGF levels occurred in those who had diabetes at baseline (9-year changes: −9.3% for IGF-I, 59.7% for IGFBP-1, −13.4% for IGFBP-3); the smallest in individuals who remained normoglycemic at follow-up (9-year changes: −3.7% for IGF-I, 25.6% for IGFBP-1, −6.4% for IGFBP-3); and intermediate changes in those who were normoglycemic but developed IFG at follow-up. Conclusion Our results demonstrate that degrees of glycemic impairment are associated with varying levels of changes in IGF proteins. The exaggerated changes observed in the diabetes group have been previously shown to be associated with heart failure, cancer and non-cancer mortality. PMID:25989565

  16. Impact of exogenous growth hormone on GH/IGF/IGFBP axis in colon cancer-bearing nude mice%生长激素荷人结肠癌裸鼠GH/IGF-I/IGFBP-3轴的影响

    Institute of Scientific and Technical Information of China (English)

    张毅; 梁道明; 李思齐; 袁勇; 赵辉; 陈嘉勇

    2013-01-01

    目的:探讨外源性生长激素(GH)对荷瘤裸鼠GH/胰岛素样生长因子(IGF)/胰岛素样生长因子结合蛋白3(IGFBP-3)轴的影响.方法:采用人结肠癌细胞株(HCT116)建立人结肠癌细胞裸鼠移植瘤模型.取48只荷瘤裸鼠随机均分为生理盐水处理组(NS组)、氟尿嘧啶处理组(FU组)、GH处理组(GH组),FU+GH处理组(FU+GH组).每组连续给药6d,在给药结束后24,72 h分别处死每组6只动物,取血及移植瘤标本,应用ELISA法检测血清GH,IGF-I,IGFBP-3含量和RT-PCR法检测移植瘤IGF-I,IGF-I受体(IGF-IR),IGFBP-3的mRNA表达.结果:ELISA结果显示,给药结束后24 h,GH组和FU+GH组血清GH,IGF-I,IGFBP-3含量较NS组与FU组明显升高(均P<0.05);给药结束后72 h,各组GH,IGF-I的水平无统计学差异(均P>0.05),但GH组和FU+GH组IGFBP-3水平仍高于NS组和FU组(均P<0.05).RT-PCR结果显示,给药结束后24 h,GH,FU,FU+GH组移植瘤组织IGF-I mRNA与IGF-IR mRNA的表达较NS组明显降低,而IGFBP-3 mRNA表达明显增加;给药结束后72 h,IGF-I mRNA与IGF-IR mRNA表达各组间无差别,但GH组,FU组和FU+GH组IGFBP-3 mRNA表达量仍明显高于NS组.结论:短期应用外源性GH所致GH/IGF/IGFBP-3轴的变化对人结肠癌移植瘤生长无促进作用.%Objective: To observe the impact of exogenous growth hormone (GH) on the axis of GH/insulin-like growth factor I (IGF-I)/insulin-like growth factor binding protein (GFBP) in colon cancer-bearing nude mice. Methods: Nude mice xenograft models of human colon cancer were established by using human colon cancer HCT116 cells. Subsequently, 48 tumor-bearing mice were equally randomized into normal saline treatment group (NS group), fluorouracil treatment group (FU group), GH treatment group (GH group) and FU plus GH treatment group (FU+GH group), and all treatment regimens were continued for 6 days. Mice were sacrificed to collect the blood and tumor xenograft samples at 24 and 72 h after the termination of regimens with 6

  17. Acyl-coenzyme A binding protein, ACBP

    DEFF Research Database (Denmark)

    Kragelund, Birthe Brandt; Knudsen, J.; Poulsen, Flemming

    1999-01-01

    Acyl-coenzyme A binding proteins are known from a large group of eukaryote species and to bind a long chain length acyl-CoA ester with very high affinity. Detailed biochemical mapping of ligand binding properties has been obtained as well as in-depth structural studies on the bovine apo-protein...... and of the complex with palmitoyl-CoA using NMR spectroscopy. In the four a-helix bundle structure, a set of 21 highly conserved residues present in more that 90% of all known sequences of acyl-coenzyme A binding proteins constitutes three separate mini-cores. These residues are predominantly located at the helix......-helix interfaces. From studies of a large set of mutant proteins the role of the conserved residues has been related to structure, function, folding and stability....

  18. Acyl-coenzyme A binding protein (ACBP)

    DEFF Research Database (Denmark)

    Kragelund, B B; Knudsen, J; Poulsen, F M

    1999-01-01

    and of the complex with palmitoyl-CoA using NMR spectroscopy. In the four alpha-helix bundle structure, a set of 21 highly conserved residues present in more that 90% of all known sequences of acyl-coenzyme A binding proteins constitutes three separate mini-cores. These residues are predominantly located......Acyl-coenzyme A binding proteins are known from a large group of eukaryote species and to bind a long chain length acyl-CoA ester with very high affinity. Detailed biochemical mapping of ligand binding properties has been obtained as well as in-depth structural studies on the bovine apo-protein...... at the helix-helix interfaces. From studies of a large set of mutant proteins the role of the conserved residues has been related to structure, function, folding and stability....

  19. Identification of Differentially Expressed IGFBP5-Related Genes in Breast Cancer Tumor Tissues Using cDNA Microarray Experiments.

    Science.gov (United States)

    Akkiprik, Mustafa; Peker, İrem; Özmen, Tolga; Amuran, Gökçe Güllü; Güllüoğlu, Bahadır M; Kaya, Handan; Özer, Ayşe

    2015-11-10

    IGFBP5 is an important regulatory protein in breast cancer progression. We tried to identify differentially expressed genes (DEGs) between breast tumor tissues with IGFBP5 overexpression and their adjacent normal tissues. In this study, thirty-eight breast cancer and adjacent normal breast tissue samples were used to determine IGFBP5 expression by qPCR. cDNA microarrays were applied to the highest IGFBP5 overexpressed tumor samples compared to their adjacent normal breast tissue. Microarray analysis revealed that a total of 186 genes were differentially expressed in breast cancer compared with normal breast tissues. Of the 186 genes, 169 genes were downregulated and 17 genes were upregulated in the tumor samples. KEGG pathway analyses showed that protein digestion and absorption, focal adhesion, salivary secretion, drug metabolism-cytochrome P450, and phenylalanine metabolism pathways are involved. Among these DEGs, the prominent top two genes (MMP11 and COL1A1) which potentially correlated with IGFBP5 were selected for validation using real time RT-qPCR. Only COL1A1 expression showed a consistent upregulation with IGFBP5 expression and COL1A1 and MMP11 were significantly positively correlated. We concluded that the discovery of coordinately expressed genes related with IGFBP5 might contribute to understanding of the molecular mechanism of the function of IGFBP5 in breast cancer. Further functional studies on DEGs and association with IGFBP5 may identify novel biomarkers for clinical applications in breast cancer.

  20. Periplasmic binding proteins: a versatile superfamily for protein engineering.

    Science.gov (United States)

    Dwyer, Mary A; Hellinga, Homme W

    2004-08-01

    The diversity of biological function, ligand binding, conformational changes and structural adaptability of the periplasmic binding protein superfamily have been exploited to engineer biosensors, allosteric control elements, biologically active receptors and enzymes using a combination of techniques, including computational design. Extensively redesigned periplasmic binding proteins have been re-introduced into bacteria to function in synthetic signal transduction pathways that respond to extracellular ligands and as biologically active enzymes.

  1. Prediction of HLA-A 2.1-restricted CTL epitopes from IGFBP7 antigen of lung carcinoma

    Institute of Scientific and Technical Information of China (English)

    Zhao Weipeng; Long Haixia; Zhu Bo; Duan Yuzhong; Chen Zhengtang

    2009-01-01

    Objective: With the development of peptide-based cancer specific immunotherapy, the prediction of CTL epitopes from insulin-like growth factor-binding protein 7 (IGFBP7) is very important for some research about tumor metastasis. Because HLA-A2.1-expressing individuals cover >50% in the population of China, we aimed at identifying IGFBP7-encoded peptide presented by HLA-A2.1. Methods: In our study, a HLA-A2.1 restricted CTL epitope was identified by using the following two-step procedure: (a) computer-based epitope prediction from the amino acid sequence of IGFBP7 antigen; (b) Validation with epitope molecular modeling. Results: We obtained four epitopes with high immunogenicity scores by all of the three algorithms, i.e., BIMAS, SYFPEITHI and IMTECH. Each of the four candidates satisfied the criteria of the HLA-A2.1-restricted CTL epitopes in molecular modeling analysis. Conclusion: The combination of BIMAS, SYFPEITHI and IMTECH method can improve the prediction efficiency and accuracy. Due to this research herein, this four epitopes have potential value for further studied, also have potential application in peptide-mediated immunotherapy. These epitopes may be useful in the design of therapeutic peptide vaccine for lung carcinoma and as immunotherapeutic strategies against lung carcinoma after identified by immunology experiment.

  2. Clinical studies of IGFBP-2 by radioimmunoassay

    DEFF Research Database (Denmark)

    Blum, W F; Horn, N; Kratzsch, J

    1993-01-01

    A specific radioimmunoassay for human IGFBP-2 was developed using a polyclonal antiserum directed against a partial sequence (hIGFBP-2(176-190)). The tracer was prepared by radioiodination of a [Tyr]o-hIGFBP-2(176-190) derivative. The assay was used to study IGFBP-2 levels in numerous clinical...... and experimental situations. There was little circadian fluctuations of serum level which showed a marked age-dependence with high levels at birth and senescence and low levels during puberty. Decreased IGFBP-2 levels were present in untreated insulin-dependent diabetes mellitus (IDDM), in acromegaly and during...... dexamethasone suppression test. GH deficiency, fasting, IGF-I administration to patients with GH receptor deficiency, hepatic failure and insulinomas caused a moderate increase of serum IGFBP-2. Markedly elevated levels were found in chronic renal failure, non-islet cell tumour induced hypoglycemia...

  3. Lipid binding proteins from parasitic platyhelminthes.

    Science.gov (United States)

    Alvite, Gabriela; Esteves, Adriana

    2012-01-01

    TWO MAIN FAMILIES OF LIPID BINDING PROTEINS HAVE BEEN IDENTIFIED IN PARASITIC PLATYHELMINTHES: hydrophobic ligand binding proteins (HLBPs) and fatty acid binding proteins (FABPs). Members of the former family of proteins are specific to the Cestoda class, while FABPs are conserved across a wide range of animal species. Because Platyhelminthes are unable to synthesize their own lipids, these lipid-binding proteins are important molecules in these organisms. HLBPs are a high molecular mass complex of proteins and lipids. They are composed of subunits of low molecular mass proteins and a wide array of lipid molecules ranging from CoA esters to cholesterol. These proteins are excretory-secretory molecules and are key serological tools for diagnosis of diseases caused by cestodes. FABPs are mainly intracellular proteins of low molecular weight. They are also vaccine candidates. Despite that the knowledge of their function is scarce, the differences in their molecular organization, ligand preferences, intra/extracellular localization, evolution, and phylogenetic distribution, suggest that platyhelminths HLBPs and FABPs should play different functions. FABPs might be involved in the removal of fatty acids from the inner surface of the cell membrane and in their subsequent targeting to specific cellular destinations. In contrast, HLBPs might be involved in fatty acid uptake from the host environment.

  4. Lipid Binding Proteins from Parasitic Platyhelmithes

    Directory of Open Access Journals (Sweden)

    Gabriela eAlvite

    2012-09-01

    Full Text Available Two main families of lipid binding proteins have been identified in parasitic Platyhelminthes: hydrophobic ligand binding proteins (HLBPs and fatty acid binding proteins (FABPs. Members of the former family of proteins are specific to the Cestoda class, while FABPs are conserved across a wide range of animal species. Because Platyhelminthes are unable to synthesise their own lipids, these lipid-binding proteins are important molecules in these organisms.HLBPs are a high molecular mass complex of proteins and lipids. They are composed of subunits of low molecular mass proteins and a wide array of lipid molecules ranging from CoA esters to cholesterol. These proteins are excretory-secretory molecules and are key serological tools for diagnosis of diseases caused by cestodes. FABPs are mainly intracellular proteins of low molecular weight. They are also vaccine candidates.Despite that the knowledge of their function is scarce, the differences in their molecular organisation, ligand preferences, intra/extracellular localisation, evolution, and phylogenetic distribution, suggest that platyhelminths HLBPs and FABPs should play different functions. FABPs might be involved in the removal of fatty acids from the inner surface of the cell membrane and in their subsequent targeting to specific cellular destinations. In contrast, HLBPs might be involved in fatty acid uptake from the host environment.

  5. Haptenation: Chemical Reactivity and Protein Binding

    Directory of Open Access Journals (Sweden)

    Itai Chipinda

    2011-01-01

    Full Text Available Low molecular weight chemical (LMW allergens are commonly referred to as haptens. Haptens must complex with proteins to be recognized by the immune system. The majority of occupationally related haptens are reactive, electrophilic chemicals, or are metabolized to reactive metabolites that form covalent bonds with nucleophilic centers on proteins. Nonelectrophilic protein binding may occur through disulfide exchange, coordinate covalent binding onto metal ions on metalloproteins or of metal allergens, themselves, to the major histocompatibility complex. Recent chemical reactivity kinetic studies suggest that the rate of protein binding is a major determinant of allergenic potency; however, electrophilic strength does not seem to predict the ability of a hapten to skew the response between Th1 and Th2. Modern proteomic mass spectrometry methods that allow detailed delineation of potential differences in protein binding sites may be valuable in predicting if a chemical will stimulate an immediate or delayed hypersensitivity. Chemical aspects related to both reactivity and protein-specific binding are discussed.

  6. IGF-1、IGFBP-4和PAPPA在非小细胞肺癌患者血清的浓度及其临床意义%Serum levels and clinical signiifcance of IGF1, IGFBP-4 and PAPPA in non-small cell lung cancer

    Institute of Scientific and Technical Information of China (English)

    汤敏; 潘泓; 黄耀元; 吴俊伟; 唐诗聪; 刘德森

    2015-01-01

    Background and purpose:It is increasingly focused on that insulin-like growth factor 1 (IGF-1) and insulin-like growth factor binding protein 4 (IGFBP-4) effect cell proliferation, differentiation and apoptosis of tumor cells, and pregnancy-associated plasma protein-A (PAPPA) plays an important role in IGF-1-dependent IGFBP-4 protease mechanism that regulats tumor cells' growth. This study aimed to investigate the serum levels and clinical signiifcance of IGF-1, IGFBP-4, and PAPPA in patients with non-small cell lung cancer (NSCLC). Methods:IGF-1, IGFBP-4, and PAPPA plasma levels were measured by enzyme-linked immunosorbent assay from 82 patients with NSCLC and 40 control subjects, then the correlations between variables were assessed by Spearman correlation analysis, and associations between the IGFs variables and lung cancer risk were calculated through the odds ratio (OR) and its 95%conifdence interval (CI) with the use of unconditional logistic regression analysis. Results:Serum levels of IGF-1, IGFBP-4 and PAPPA in NSCLC patients were signiifcantly higher than those in the control group(P<0.05). There was a signiifcant positive correlation between the serum IGF-1 levels and PAPPA levels (r=0.835,P=0.000), and a negative correlation with IGFBP-4 levels (r=-0.612,P=0.000). IGFBP-4 and PAPPA levels were negatively correlated(r=-0.673, P=0.000). High plasma levels of IGF-1(OR=2.28, 95%CI: 1.25-4.36,P=0.008) and PAPPA (OR=1.64, 95%CI: 0.89-3.01,P=0.046)were associated with an increased risk of lung cancer, however high plasma levels of IGFBP-4(OR=0.54, 95%CI:0.30-1.01,P=0.047)were associated with reduced risk of lung cancer. Conclusion:To detect IGF-1, IGFBP-4 and PAPPA in serum in NSCLC patients is meaningful for the clinical auxiliary diagnosis and biology behavior prediction of NSCLC. And further study of signal transduction pathways of IGFs with the occurrence and development of NSCLC is a meaningful research direction.%背景与目

  7. Computational search for aflatoxin binding proteins

    Science.gov (United States)

    Wang, Ying; Liu, Jinfeng; Zhang, Lujia; He, Xiao; Zhang, John Z. H.

    2017-10-01

    Aflatoxin is one of the mycotoxins that contaminate various food products. Among various aflatoxin types (B1, B2, G1, G2 and M1), aflatoxin B1 is the most important and the most toxic one. In this study, through computational screening, we found that several proteins may bind specifically with different type of aflatoxins. Combination of theoretical methods including target fishing, molecular docking, molecular dynamics (MD) simulation, MM/PBSA calculation were utilized to search for new aflatoxin B1 binding proteins. A recently developed method for calculating entropic contribution to binding free energy called interaction entropy (IE) was employed to compute the binding free energy between the protein and aflatoxin B1. Through comprehensive comparison, three proteins, namely, trihydroxynaphthalene reductase, GSK-3b, and Pim-1 were eventually selected as potent aflatoxin B1 binding proteins. GSK-3b and Pim-1 are drug targets of cancers or neurological diseases. GSK-3b is the strongest binder for aflatoxin B1.

  8. Rat Mannose-Binding Protein A Binds CD14

    OpenAIRE

    Chiba, Hirofumi; Sano, Hitomi; Iwaki, Daisuke; Murakami, Seiji; Mitsuzawa, Hiroaki; Takahashi, Toru; Konishi, Masanori; Takahashi, Hiroki; Kuroki, Yoshio

    2001-01-01

    Lipopolysaccharide (LPS) has been known to induce inflammation by interacting with CD14, which serves as a receptor for LPS. Mannose-binding protein (MBP) belongs to the collectin subgroup of the C-type lectin superfamily, along with surfactant proteins SP-A and SP-D. We have recently demonstrated that SP-A modulates LPS-induced cellular responses by interaction with CD14 (H. Sano, H. Sohma, T. Muta, S. Nomura, D. R. Voelker, and Y. Kuroki, J. Immunol. 163:387–395, 2000) and that SP-D also in...

  9. Total and free insulin-like growth factor I, insulin-like growth factor binding protein 3 and acid-labile subunit reflect clinical activity in acromegaly

    DEFF Research Database (Denmark)

    Sneppen, S B; Lange, Merete Wolder; Pedersen, L M

    2001-01-01

    The aim was to evaluate, markers of disease activity in acromegaly in relation to perceived disease activity. Thirty-seven consecutively treated, acromegalic patients, classified by clinical symptoms as inactive (n=16), slightly active (n=10) and active (n=11), entered the study. When evaluating......-like growth factor binding protein-3 (IGFBP-3) with PV(pos) of 0.69 and 0.71 and PV(neg) of 0.91 and 0.92 respectively. We conclude that free IGF-I is more closely related than total IGF-I to perceived disease activity and is as such useful when evaluating previously treated acromegaly for disease activity...

  10. Lycopene supplementation elevates circulating insulin-like growth factor-binding protein-1 and-2 concentrations in persons at greater risk of colorectal cancer

    OpenAIRE

    Vrieling, A.; Voskuil, D.W.; Bonfrer, J.M.; Korse, C M; van Doorn, J.; Cats, A; Depla, A.C.; Timmer, R; Witteman, B.J.M.; Leeuwen, van, P.J.; van 't Veer, L J; Rookus, M A; Kampman, E.

    2007-01-01

    Background: Higher circulating insulin-like growth factor I (IGF-I) concentrations have been related to a greater risk of cancer. Lycopene intake is inversely associated with cancer risk, and experimental studies have shown that it may affect the IGF system, possibly through an effect on IGF-binding proteins (IGFBPs). Objective: The objective of our study was to investigate the effect of an 8-wk supplementation with tomato-derived lycopene (30 mg/d) on serum concentrations of total IGF-I, IGF...

  11. Ancestral Protein Reconstruction Yields Insights into Adaptive Evolution of Binding Specificity in Solute-Binding Proteins.

    Science.gov (United States)

    Clifton, Ben E; Jackson, Colin J

    2016-02-18

    The promiscuous functions of proteins are an important reservoir of functional novelty in protein evolution, but the molecular basis for binding promiscuity remains elusive. We used ancestral protein reconstruction to experimentally characterize evolutionary intermediates in the functional expansion of the polar amino acid-binding protein family, which has evolved to bind a variety of amino acids with high affinity and specificity. High-resolution crystal structures of an ancestral arginine-binding protein in complex with l-arginine and l-glutamine show that the promiscuous binding of l-glutamine is enabled by multi-scale conformational plasticity, water-mediated interactions, and selection of an alternative conformational substate productive for l-glutamine binding. Evolution of specialized glutamine-binding proteins from this ancestral protein was achieved by displacement of water molecules from the protein-ligand interface, reducing the entropic penalty associated with the promiscuous interaction. These results provide a structural and thermodynamic basis for the co-option of a promiscuous interaction in the evolution of binding specificity.

  12. L-Carnitine changes the levels of insulin-like growth factors (IGFs) and IGF binding proteins in streptozotocin-induced diabetic rat.

    Science.gov (United States)

    Heo, Y R; Kang, C W; Cha, Y S

    2001-10-01

    This study investigated the effects of L-carnitine on insulin-like growth factor-I/II (IGF-I/II) and insulin-like growth factor binding proteins (IGFBPs) in streptozotocin (STZ)-induced diabetic rats. Each rat in the three L-carnitine-treated groups was injected subcutaneously with L-carnitine, 50 (D50), 100 (D100), or 200 (D200) mg/kg body weight every other day for four weeks, and animals in normal (N) and diabetic (DM) groups received saline by the same method. Diabetic rats had significantly lower carnitine concentrations in serum and liver compared with normal rats. Total carnitine concentrations were increased dose-dependently by carnitine treatment. Total IGF-I in serum from diabetic rats was increased dose-dependently by carnitine treatment, but was statistically significant only in the D200 group. The expression of liver IGF-I mRNA was lower in diabetic rats than in normal rats and increased by L-carnitine treatment. L-Carnitine treatment of diabetic rats had no effect on the levels of IGF-II in serum, liver, and kidney. Although the levels of IGF-II in serum and kidney of diabetic rats were increased in comparison with normal rats, IGF-II mRNA was not expressed in liver. Diabetic rats had markedly lower IGFBP-3 than normal rats did, and IGFBP-3 was increased by L-carnitine treatment. These results demonstrate that L-carnitine treatment of diabetic rats modulates the IGFs/IGFBPs axis. Especially note-worthy is that L-carnitine at a dose of 200 mg/kg/48 h for four weeks was able to restore serum total IGF-I in STZ-induced diabetic rats to nearly normal levels.

  13. Aspects of Protein, Chemistry, Part II: Oxygen-Binding Proteins

    Science.gov (United States)

    Nixon, J. E.

    1977-01-01

    Compares differences in function and behavior of two oxygen-binding proteins, myoglobin found in muscle and hemoglobin found in blood. Describes the mechanism of oxygen-binding and allosteric effect in hemoglobin; also describes the effect of pH on the affinity of hemoglobin for oxygen. (CS)

  14. Associations of serum insulin-like growth factor-I and insulin-like growth factor-binding protein 3 levels with biomarker-calibrated protein, dairy product and milk intake in the Women's Health Initiative.

    Science.gov (United States)

    Beasley, Jeannette M; Gunter, Marc J; LaCroix, Andrea Z; Prentice, Ross L; Neuhouser, Marian L; Tinker, Lesley F; Vitolins, Mara Z; Strickler, Howard D

    2014-03-14

    It is well established that protein-energy malnutrition decreases serum insulin-like growth factor (IGF)-I levels, and supplementation of 30 g of whey protein daily has been shown to increase serum IGF-I levels by 8 % after 2 years in a clinical trial. Cohort studies provide the opportunity to assess associations between dietary protein intake and IGF axis protein levels under more typical eating conditions. In the present study, we assessed the associations of circulating IGF axis protein levels (ELISA, Diagnostic Systems Laboratories) with total biomarker-calibrated protein intake, as well as with dairy product and milk intake, among postmenopausal women enrolled in the Women's Health Initiative (n 747). Analyses were carried out using multivariate linear regression models that adjusted for age, BMI, race/ethnicity, education, biomarker-calibrated energy intake, alcohol intake, smoking, physical activity and hormone therapy use. There was a positive association between milk intake and free IGF-I levels. A three-serving increase in milk intake per d (approximately 30 g of protein) was associated with an estimated average 18·6 % higher increase in free IGF-I levels (95 % CI 0·9, 39·3 %). However, total IGF-I and insulin-like growth factor-binding protein 3 (IGFBP-3) levels were not associated with milk consumption and nor were there associations between biomarker-calibrated protein intake, biomarker-calibrated energy intake, and free IGF-I, total IGF-I or IGFBP-3 levels. The findings of the present study carried out in postmenopausal women are consistent with clinical trial data suggesting a specific relationship between milk consumption and serum IGF-I levels, although in the present study this association was only statistically significant for free, but not total, IGF-I or IGFBP-3 levels.

  15. Increased fat mass, decreased myofiber size, and a shift to glycolytic muscle metabolism in adolescent male transgenic mice overexpressing IGFBP-2.

    Science.gov (United States)

    Rehfeldt, Charlotte; Renne, Ulla; Sawitzky, Mandy; Binder, Gerhard; Hoeflich, Andreas

    2010-08-01

    To elucidate the functional role of insulin-like growth factor (IGF)-binding protein-2 (IGFBP-2) for in vivo skeletal muscle growth and function, skeletal muscle cellularity and metabolism, expression of signal molecules, and body growth and composition were studied in a transgenic mouse model overexpressing IGFBP-2. Postnatal growth rate of transgenic mice was reduced from day 21 of age by 6-8% compared with nontransgenic controls. At 10 wk of age body lean protein and moisture percentages were lower, whereas fat percentage was higher in IGFBP-2 transgenic mice. Muscle weights were reduced (-13% on day 30 of age, -14% on day 72), which resulted from slower growth of myofibers in size but not from decreases in myofiber number. The reduction in muscle mass was associated with lower total DNA, RNA, and protein contents as well as greater DNA/RNA and protein/RNA ratios. The percentage of proliferating (Ki-67-positive) nuclei within myofibers was reduced (3.4 vs. 5.8%) in 30-day-old transgenic mice. These changes were accompanied by slight reductions in specific p44/42 MAPK activity (-18% on day 72) and, surprisingly, by increased levels of phosphorylated Akt (Ser(473)) (+25% on day 30, +66% on day 72). The proportion of white glycolytic fibers (55.9 vs. 53.5%) and the activity of lactate dehydrogenase (+8%) were elevated in 72-day-old transgenic mice. Most of the differences observed between transgenic and nontransgenic mice were more pronounced in males. The results suggest that IGFBP-2 significantly inhibits postnatal skeletal myofiber growth by decreasing myogenic proliferation and protein accretion and enhances glycolytic muscle metabolism.

  16. Information flow through calcium binding proteins

    Science.gov (United States)

    Bak, Ji Hyun; Bialek, William

    2013-03-01

    Calcium signaling is a ubiquitous mode of biological communication, which regulates a great variety of vital processes in living systems. Such a signal typically begins with an elementary event, in which calcium ions bind to a protein, inducing a change in the protein's structure. Information can only be lost, from what was conveyed through this initial event, as the signal is further transduced through the downstream networks. In the present work we analyze and optimize the information flow in the calcium binding process. We explicitly calculate the mutual information between the calcium concentration and the states of the protein, using a simple model for allosteric regulation in a dimeric protein. The optimal solution depends on the dynamic range of the input as well as on the timescale of signal integration. According to our result, the optimizing strategy involves allowing the calcium-binding protein to be ``activated'' by a partial occupation of its sites, and tuning independently the strengths of cooperative interactions in the binding and unbinding processes.

  17. DIAGNOSTIC VALUE OF SERUM INSULIN—LIKE GROWTH FACTOR BINDING PROTEIN—3 IN CHILDREN WITH OR WITHOUT GROWTH HORMONE DEFICIENCY

    Institute of Scientific and Technical Information of China (English)

    覃舒文; 史轶蘩; 等

    2002-01-01

    Objective:To study the value of serum insulin-like growth factor binding protein-3 (IGFBP-3) levels in differential diagnosis of growth hormone deficiency(GHD).Methods:To measure serum IGFBP-3 levels by RIA in normal children and adolescents,GHD children and short-stature children without (GHD).Methods:To measure serum IGFBP-3 levels by RIA in normal children and adolescents,GHD children and short-stature children without GHD.Results.Serum level of IGFBP-3 in 129 children with untreated GHD and with no pubertal development was 1.6±0.9mg/L,which was less than that in normal group of the same age,but overlapped with the normal children in Tanner stage I.After six-month treatment with recombinant human growth hormone(rhGH),serum level of IGFBP-3 in 59 GHD significantly increased from 1.3±0.7mg/L to 2.7±0.9mg/L,accompanied by an increase of body heights,growth velocities and serum level of IGF-1.Serum level of IGFBP-3 in 55 shortstature children without GHD was 3.3±2.2mg/L,which was not significantly different from that in normal group.Conclusion:Serum IGFBP-3 level can reflect the status of GH secretion in children with GHD and is a useful marker for differential diagnosis of GHD.

  18. ABP: a novel AMPA receptor binding protein.

    Science.gov (United States)

    Srivastava, S; Ziff, E B

    1999-04-30

    We review the cloning of a novel AMPA receptor binding protein (ABP) that interacts with GluR2/3 and is homologous to GRIP. ABP is enriched in the PSD with GluR2 and is localized to the PSD by EM. ABP binds GluR2 via the C-terminal VXI motif through a Class I PDZ interaction. ABP and GRIP can also homo- and heteromultimerize. Thus, ABP and GRIP may be involved in AMPA receptor regulation and localization, by linking it to other cytoskeletal or signaling molecules. We suggest that the ABP/GRIP and PSD-95 families form distinct scaffolds that anchor, respectively, AMPA and NMDA receptors. We are currently investigating proteins that bind ABP and that may regulate the AMPA receptor.

  19. Mitogenic properties of insulin-like growth factors I and II, insulin-like growth factor binding protein-3 and epidermal growth factor on human breast stromal cells in primary culture.

    Science.gov (United States)

    Strange, Karen S; Wilkinson, Darcy; Edin, Glenn; Emerman, Joanne T

    2004-03-01

    Insulin-like growth factors I and II (IGF-I and IGF-II) are growth factors implicated in both normal mammary gland development and breast cancer. We have previously reported on the effects of components of the IGF system on breast epithelial cells. Since data suggests that stromal-epithelial interactions play a crucial role in breast cancer, we have now investigated the mitogenic properties of IGF-I, IGF-II, insulin-like growth factor binding protein-3 (IGFBP-3) and epidermal growth factor (EGF) on human breast stromal cells in primary culture. We show that, under serum-free conditions, stromal cells are stimulated to grow in response to IGF-I and IGF-II in a dose-dependent manner. IGF-I and EGF, a potent stimulator of human breast epithelial cell growth in primary culture and also associated with breast cancer, appear to stimulate stromal cell growth in a synergistic manner. IGFBP-3 does not inhibit the stimulation of growth by IGF-I, or IGF-I plus EGF. However, IGFBP-3 does inhibit the stimulation of growth by IGF-II. In contrast to our previous results with human breast epithelial cells, IGFBP-3 does not have an IGF-independent inhibitory effect on stromal cell growth. This study is the first to address the effects of IGF-I, IGF-II and IGFBP-3 alone and in combination with EGF on human breast stromal cell growth in primary culture. Characterizing the role of the IGF system in both normal breast epithelial cells and stromal cells will aid in our understanding of the mechanisms behind the role of the IGF system in breast cancer.

  20. Insulin-like growth factor-1 (IGF-1) enhances recovery from HgCl2-induced acute renal failure: the effects on renal IGF-1, IGF-1 receptor, and IGF-binding protein-1 mRNA.

    Science.gov (United States)

    Friedlaender, M; Popovtzer, M M; Weiss, O; Nefesh, I; Kopolovic, J; Raz, I

    1995-04-01

    Several growth factors have been found to play an important role in the recovery from acute renal failure (ARF). The effect of the continuous subcutaneous infusion of human recombinant insulin-like growth factor (IGF)-1 (125 micrograms daily by osmotic minipumps) in a rat model of mercuric chloride (HgCl2)-induced ARF was examined. HgCl2 (4 mg/kg) induced ARF with a mortality that was unaffected by IGF-1. However, IGF-1 significantly enhanced functional and histologic recovery in the survivors, as measured by serum creatinine and creatinine clearance and by histologic scoring. Solution hybridization RNAase protection assays showed that renal IGF-1 mRNA, IGF-1 receptor (IGF-1R) mRNA, and IGF-binding protein-1 (IGFBP-1) mRNA were unaffected by exogenous IGF-1, but this treatment significantly increased renal IGF-1 in ARF rats compared with normal rats and ARF rats not receiving IGF-1. After ARF renal mRNA for IGF-1 was decreased, IGF-1R was unchanged and IGFBP-1 was increased. Similar changes occurred in IGF-1-infused ARF rats. Thus, (1) IGF-1 enhances recovery from nephrotoxic ARF both functionally and histologically; (2) in nephrotoxic ARF, there is (a) a reduction in IGF-1 mRNA expression that is not prevented by IGF-1 infusion, and (b) an increase in renal IGFBP-1 mRNA. This may allow a significant increase in renal IGF-1 levels in IGF-1-infused ARF rats, despite the decrease in renal IGF-1 mRNA. A local increase in renal IGFBP-1 and IGF-1 may explain the accelerated recovery from ATN in this model. It was concluded that HgCl2-induced ARF is amenable to improvement by IGF-1 infusion and that the increase in renal IGFBP-1 mRNA may be an important modulator in the recovery of the kidney.

  1. ALG-2, a multifunctional calcium binding protein?

    DEFF Research Database (Denmark)

    Tarabykina, Svetlana; Mollerup, Jens; Winding Gojkovic, P.;

    2004-01-01

    ALG-2 was originally discovered as a pro-apoptotic protein in a genetic screen. Due to its ability to bind calcium with high affinity it was postulated to provide a link between the known effect of calcium in programmed cell death and the molecular death execution machinery. This review article...

  2. Development of a glucose binding protein biosensor

    Science.gov (United States)

    Dweik, M.; Milanick, M.; Grant, S.

    2007-09-01

    Glucose binding protein (GBP) is a monomeric periplasmic protein. It is synthesized in the cytoplasm of Escherichia coli which functions as a receptor for transport D-glucose. GBP binds glucose with high affinity. The binding mechanism is based on a hinge motion due to the protein conformational change. This change was utilized as an optical sensing mechanism by applying Fluorescence Resonance Energy Transfer (FRET). The wild-type GBP lacks cysteine in its structure, but by introducing a single cysteine at a specific site by site-directed mutagenesis, this ensured single-label attachment at specific sites with a fluorescent probe. The other sites were amino sites, which were labeled with second fluorophore. The near IR FRET pair, Alexa Fluor 680 (AF680) and Alexa Fluor 750(AF750), was utilized. The AF680 targeted the amine sites, which was the donor fluorophore, while the AF750 labeled the single cysteine site, which was the acceptor fluorophore. The sensing system strategy was based on the fluorescence changes of the probe as the protein undergoes a structural change upon binding. This biosensor had the ability to detect down to 10 uM concentrations of glucose. Next the probes were uploaded into red blood cells via hypo osmotic dialysis. The sensor responded to glucose while encapsulated with the red cells. These results showed the feasibility of an intracellular glucose biosensor.

  3. Glycogen Synthase Kinase-3 regulates IGFBP-1 gene transcription through the Thymine-rich Insulin Response Element

    Directory of Open Access Journals (Sweden)

    Marquez Rodolfo

    2004-09-01

    Full Text Available Abstract Background Hepatic expression of several gene products involved in glucose metabolism, including phosphoenolpyruvate carboxykinase (PEPCK, glucose-6-phosphatase (G6Pase and insulin-like growth factor binding protein-1 (IGFBP-1, is rapidly and completely inhibited by insulin. This inhibition is mediated through the regulation of a DNA element present in each of these gene promoters, that we call the Thymine-rich Insulin Response Element (TIRE. The insulin signalling pathway that results in the inhibition of these gene promoters requires the activation of phosphatidylinositol 3-kinase (PI 3-kinase. However, the molecules that connect PI 3-kinase to these gene promoters are not yet fully defined. Glycogen Synthase Kinase 3 (GSK-3 is inhibited following activation of PI 3-kinase. We have shown previously that inhibitors of GSK-3 reduce the activity of two TIRE-containing gene promoters (PEPCK and G6Pase, whose products are required for gluconeogenesis. Results In this report we demonstrate that in H4IIE-C3 cells, four distinct classes of GSK-3 inhibitor mimic the effect of insulin on a third TIRE-containing gene, IGFBP-1. We identify the TIRE as the minimum requirement for inhibition by these agents, and demonstrate that the target of GSK-3 is unlikely to be the postulated TIRE-binding protein FOXO-1. Importantly, overexpression of GSK-3 in cells reduces the insulin regulation of TIRE activity as well as endogenous IGFBP-1 expression. Conclusions These results implicate GSK-3 as an intermediate in the pathway from the insulin receptor to the TIRE. Indeed, this is the first demonstration of an absolute requirement for GSK-3 inhibition in insulin regulation of gene transcription. These data support the potential use of GSK-3 inhibitors in the treatment of insulin resistant states such as Type 2 diabetes mellitus, but suggest that it will be important to identify all TIRE-containing genes to assess potential side effects of these agents.

  4. Animal protein intakes during early life and adolescence differ in their relation to the growth hormone-insulin-like-growth-factor axis in young adulthood.

    Science.gov (United States)

    Joslowski, Gesa; Remer, Thomas; Assmann, Karen E; Krupp, Danika; Cheng, Guo; Garnett, Sarah P; Kroke, Anja; Wudy, Stefan A; Günther, Anke L B; Buyken, Anette E

    2013-07-01

    Recent studies provide evidence that insulin-like-growth-factor I (IGF-I) and its binding proteins (IGFBP) IGFBP-2 and IGFBP-3 are related to the risk of several common cancers. It remains to be clarified whether their concentrations can be programmed by protein intake from different sources during growth. This study addressed the hypothesis that animal protein intakes during infancy, mid-childhood, and adolescence differ in their relevance for the growth-hormone (GH)-IGF-I axis in young adulthood. Data from the Dortmund Nutritional and Anthropometric Longitudinally Designed Study participants with at least 2 plausible 3-d weighed dietary records during adolescence (age: girls, 9-14 y; boys, 10-15 y; n = 213), around the adiposity rebound (age 4-6 y; n = 179) or early life (age 0.5-2 y; n = 130), and one blood sample in young adulthood were included in the study. Mean serum concentrations of IGF-I, IGFBP-1, IGFBP-2, and IGFBP-3 were compared between tertiles of habitual animal protein intake using multivariable regression analysis. Habitually higher animal protein intakes in females during puberty were related to higher IGF-I (P-trend = 0.005) and IGFBP-3 (P-trend = 0.01) and lower IGFBP-2 (P-trend = 0.04), but not to IGFBP-1 in young adulthood. In turn, IGF-I concentrations in young adulthood were inversely related to animal protein intakes in early life among males only (P-trend = 0.03), but not to animal protein intake around adiposity rebound (P-trend > 0.5). Our data suggest that, among females, a habitually higher animal protein intake during puberty may precipitate an upregulation of the GH-IGF-I axis, which is still discernible in young adulthood. By contrast, among males, higher animal protein intakes in early life may exert a long-term programming of the GH-IGF-I axis.

  5. Short hairpin RNA targeting insulin-like growth factor binding protein-3 restores the bioavailability of insulin-like growth factor-1 in diabetic rats

    Directory of Open Access Journals (Sweden)

    Zhang-Yan Zhou

    2016-02-01

    Full Text Available ABSTRACT Purpose To investigate whether intracavernosal injection of short hairpin RNA for IGFBP-3 could improve erectile function in streptozotocin-induced diabetic rats. Materials and methods After 12 weeks of IGFBP-3 short hairpin RNA injection treatment, intracavernous pressure responses to electrical stimulation of cavernous nerves were evaluated. The expression of IGFBP-3 and IGF-1 at mRNA and protein levels were detected by quantitative real-time PCR analysis and Western blot, respectively. The concentration of cavernous cyclic guanosine monophosphate was detected by enzyme-linked immunosorbent assay. Results At 12 weeks after intracavernous administration of IGFBP-3 shRNA, the cavernosal pressure was significantly increased in response to the cavernous nerves stimulation compared to the diabetic group (P<0.05. Cavernous IGFBP-3 expression at both mRNA and protein levels was significantly inhibited. At the same time, cavernous IGF-1 expression was significantly increased in the IGFBP-3 shRNA treatment group compared to the diabetic group (P<0.01. Cavernous cyclic guanosine monophosphate concentration was significantly increased in the IGFBP-3 shRNA treatment group compared to the diabetic group (P<0.01. Conclusions Gene transfer of IGFBP-3 shRNA could improve erectile function via the restoration of cavernous IGF-1 bioavailability and an increase of cavernous cGMP concentration in the pathogenesis of erectile dysfunction in streptozotocin-induced diabetic rats.

  6. Quantifying drug-protein binding in vivo.

    Energy Technology Data Exchange (ETDEWEB)

    Buchholz, B; Bench, G; Keating III, G; Palmblad, M; Vogel, J; Grant, P G; Hillegonds, D

    2004-02-17

    Accelerator mass spectrometry (AMS) provides precise quantitation of isotope labeled compounds that are bound to biological macromolecules such as DNA or proteins. The sensitivity is high enough to allow for sub-pharmacological (''micro-'') dosing to determine macromolecular targets without inducing toxicities or altering the system under study, whether it is healthy or diseased. We demonstrated an application of AMS in quantifying the physiologic effects of one dosed chemical compound upon the binding level of another compound in vivo at sub-toxic doses [4].We are using tissues left from this study to develop protocols for quantifying specific binding to isolated and identified proteins. We also developed a new technique to quantify nanogram to milligram amounts of isolated protein at precisions that are comparable to those for quantifying the bound compound by AMS.

  7. Brain hyaluronan binding protein inhibits tumor growth

    Institute of Scientific and Technical Information of China (English)

    高锋; 曹曼林; 王蕾

    2004-01-01

    Background Great efforts have been made to search for the angiogenic inhibitors in avascular tissues. Several proteins isolated from cartilage have been proved to have anti-angiogenic or anti-tumour effects. Because cartilage contains a great amount of hyaluronic acid (HA) oligosaccharides and abundant HA binding proteins (HABP), therefore, we speculated that HABP might be one of the factors regulating vascularization in cartilage or anti-angiogenesis in tumours. The purpose of this research was to evaluale the effects of hyaluronan binding protein on inhibiting tumour growth both in vivo and vitro. Methods A unique protein termed human brain hyaluronan (HA) binding protein (b-HABP) was cloned from human brain cDNA library. MDA-435 human breast cancer cell line was chosen as a transfectant. The in vitro underlying mechanisms were investigated by determining the possibilities of MDA-435/b-HABP colony formation on soft agar, the effects of the transfectant on the proliferation of endothelial cells and the expression levels of caspase 3 and FasL from MDA-435/b-HABP. The in vivo study included tumour growth on the chorioallantoic membrane (CAM) of chicken embryos and nude mice. Results Colony formation assay revealed that the colonies formed by MDA-435/b-HABP were greatly reduced compared to mock transfectants. The conditioned media from MDA-435/b-HABP inhibited the growth of endothelial cells in culture. Caspase 3 and FasL expressions were induced by MDA-435/b-HABP. The size of tumours of MDA-435/b-HABP in both CAM and nude mice was much smaller than that of MDA-435 alone. Conclusions Human brain hyaluronan binding protein (b-HABP) may represent a new kind of naturally existing anti-tumour substance. This brain-derived glycoprotein may block tumour growth by inducing apoptosis of cancer cells or by decreasing angiogenesis in tumour tissue via inhibiting proliferation of endothelial cells.

  8. Free and total insulin-like growth factors and insulin-like growth factor binding proteins during 14 days of growth hormone administration in healthy adults.

    Science.gov (United States)

    Skjaerbaek, C; Frystyk, J; Møller, J; Christiansen, J S; Orskov, H

    1996-12-01

    The objective was to investigate the effect of growth hormone (GH) administration on circulating levels of free insulin-like growth factors (IGFs) in healthy adults. Eight healthy male subjects were given placebo and two doses of GH (3 and 6 IU/m2 per day) for 14 days in a double-blind crossover study. Fasting blood samples were obtained every second day. Free IGF-I and IGF-II were determined by ultrafiltration of serum. Total IGF-I and IGF-II were measured after acid-ethanol extraction. In addition, GH, insulin, IGF binding protein 1 (IGFBP-1) and IGFBP-3 were measured. Serum-free and total IGF-I increased in a dose-dependent manner during the 14 days of GH administration. After 14 days, serum-free IGF-I values were 610 +/- 100 ng/l (mean +/- SEM) (placebo), 2760 +/- 190 ng/l (3 IU/ m2) and 3720 +/- 240 ng/l (6 IU/m2) (p = 0.0001 for 3 and 6 IU/m2 vs placebo; p = 0.004 for 3 IU/m2 vs 6 IU/m2). Total IGF-I values were 190 +/- 10 micrograms/l (placebo), 525 +/- 10 (3 IU/m2), and 655 +/- 40 micrograms/l (6 IU/m2) (p Insulin-like growth factor binding protein 1 was decreased during GH administration (p = 0.04 for placebo vs 3 IU/m2; p = 0.006 for placebo vs 6 IU/m2). In conclusion, fasting serum free IGF-I increased dose dependently during GH administration and free IGF-I increased relatively more than total IGF-I. This may partly be due to the decrease in IGFBP-1.

  9. Insulin-like growth factors, insulin-like growth factor-binding proteins, insulin-like growth factor-binding protein-3 protease, and growth hormone-binding protein in lipodystrophic human immunodeficiency virus-infected patients

    DEFF Research Database (Denmark)

    Haugaard, Steen B; Andersen, Ove; Hansen, Birgitte Rønde

    2004-01-01

    concentration were increased (>90%, P .5), whereas, in LIPO, IGFBP-1 and IGFBP-2 were reduced (-36%, P ...). In pooled groups, total IGF-I, free IGF-I, total IGF-II, and IGFBP-3, respectively, correlated inversely with age (all P IGFBP-2 correlated positively with insulin sensitivity (age-adjusted all P

  10. A structural classification of substrate-binding proteins

    NARCIS (Netherlands)

    Berntsson, Ronnie P. -A.; Smits, Sander H. J.; Schmitt, Lutz; Slotboom, Dirk-Jan; Poolman, Bert

    2010-01-01

    Substrate-binding proteins (SBP) are associated with a wide variety of protein complexes. The proteins are part of ATP-binding cassette transporters for substrate uptake, ion gradient driven transporters, DNA-binding proteins, as well as channels and receptors from both pro-and eukaryotes. A wealth

  11. Polynucleotides encoding TRF1 binding proteins

    Science.gov (United States)

    Campisi, Judith; Kim, Sahn-Ho

    2002-01-01

    The present invention provides a novel telomere associated protein (Trf1-interacting nuclear protein 2 "Tin2") that hinders the binding of Trf1 to its specific telomere repeat sequence and mediates the formation of a Tin2-Trf1-telomeric DNA complex that limits telomerase access to the telomere. Also included are the corresponding nucleic acids that encode the Tin2 of the present invention, as well as mutants of Tin2. Methods of making, purifying and using Tin2 of the present invention are described. In addition, drug screening assays to identify drugs that mimic and/or complement the effect of Tin2 are presented.

  12. IGFBP-4 Anti-Angiogenic and Anti-Tumorigenic Effects Are Associated with Anti-Cathepsin B Activity

    Directory of Open Access Journals (Sweden)

    María J Moreno

    2013-05-01

    Full Text Available Insulin-like growth factor-binding protein 4 (IGFBP-4/IBP-4 has potent IGF-independent anti-angiogenic and antitumorigenic effects. In this study, we demonstrated that these activities are located in the IGFBP-4 C-terminal protein fragment (CIBP-4, a region containing a thyroglobulin type 1 (Tg1 domain. Proteins bearing Tg1 domains have been shown to inhibit cathepsins, lysosomal enzymes involved in basement membrane degradation and implicated in tumor invasion and angiogenesis. In our studies, CIBP-4 was shown to internalize and co-localize with lysosomal-like structures in both endothelial cells (ECs and glioblastoma U87MG cells. CIBP-4 also inhibited both growth factor-induced EC tubulogenesis in Matrigel and the concomitant increases in intracellular cathepsin B (CatB activity. In vitro assays confirmed CIBP-4 capacity to block recombinant CatB activity. Biodistribution analysis of intravenously injected CIBP-4-Cy5.5 in a glioblastoma tumor xenograft model indicated targeted accumulation of CIBP-4 in tumors. Most importantly, CIBP-4 reduced tumor growth in this animal model by 60%. Pleiotropic anti-angiogenic and anti-tumorigenic activities of CIBP-4 most likely underlie its observed therapeutic potential against glioblastoma.

  13. Preliminary screening of differentially expressed genes involved in methyl-CpG-binding protein 2 gene-mediated proliferation in human osteosarcoma cells.

    Science.gov (United States)

    Meng, Gang; Li, Yi; Lv, YangFan; Dai, Huanzi; Zhang, Xi; Guo, Qiao-Nan

    2015-04-01

    Methyl-CpG-binding protein 2 (MeCP2) is essential in human brain development and has been linked to several cancer types and neuro-developmental disorders. This study aims to screen the MeCP2 related differentially expressed genes and discover the therapeutic targets for osteosarcoma. CCK8 assay was used to detect the proliferation and SaOS2 and U2OS cells. Apoptosis of cells was detected by flow cytometry analysis that monitored Annexin V-APC/7-DD binding and 7-ADD uptake simultaneously. Denaturing formaldehyde agarose gel electrophoresis was employed to examine the quality of total RNA 18S and 28S units. Gene chip technique was utilized to discover the differentially expressed genes correlated with MeCP2 gene. Differential gene screening criteria were used to screen the changed genes. The gene up-regulation or down-regulation more than 1.5 times was regarded as significant differential expression genes. The CCK8 results indicated that the cell proliferation of MeCP2 silencing cells (LV-MeCP2-RNAi) was significantly decreased compared to non-silenced cells (LV-MeCP2-RNAi-CN) (P genes were screened from a total of 49,395 transcripts. Among the total 107 transcripts, 34 transcripts were up-regulated and 73 transcripts were down-regulated. There were five significant differentially expressed genes, including IGFBP4, HOXC8, LMO4, MDK, and CTGF, which correlated with the MeCP2 gene. The methylation frequency of CpG in IGFBP4 gene could achieve 55%. In conclusion, the differentially expressed IGFBP4, HOXC8, LMO4, MDK, and CTGF genes may be involved in MeCP2 gene-mediated proliferation and apoptosis in osteosarcoma cells.

  14. Evidence that breast cancer risk at the 2q35 locus is mediated through IGFBP5 regulation.

    Science.gov (United States)

    Ghoussaini, Maya; Edwards, Stacey L; Michailidou, Kyriaki; Nord, Silje; Cowper-Sal Lari, Richard; Desai, Kinjal; Kar, Siddhartha; Hillman, Kristine M; Kaufmann, Susanne; Glubb, Dylan M; Beesley, Jonathan; Dennis, Joe; Bolla, Manjeet K; Wang, Qin; Dicks, Ed; Guo, Qi; Schmidt, Marjanka K; Shah, Mitul; Luben, Robert; Brown, Judith; Czene, Kamila; Darabi, Hatef; Eriksson, Mikael; Klevebring, Daniel; Bojesen, Stig E; Nordestgaard, Børge G; Nielsen, Sune F; Flyger, Henrik; Lambrechts, Diether; Thienpont, Bernard; Neven, Patrick; Wildiers, Hans; Broeks, Annegien; Van't Veer, Laura J; Th Rutgers, Emiel J; Couch, Fergus J; Olson, Janet E; Hallberg, Emily; Vachon, Celine; Chang-Claude, Jenny; Rudolph, Anja; Seibold, Petra; Flesch-Janys, Dieter; Peto, Julian; Dos-Santos-Silva, Isabel; Gibson, Lorna; Nevanlinna, Heli; Muranen, Taru A; Aittomäki, Kristiina; Blomqvist, Carl; Hall, Per; Li, Jingmei; Liu, Jianjun; Humphreys, Keith; Kang, Daehee; Choi, Ji-Yeob; Park, Sue K; Noh, Dong-Young; Matsuo, Keitaro; Ito, Hidemi; Iwata, Hiroji; Yatabe, Yasushi; Guénel, Pascal; Truong, Thérèse; Menegaux, Florence; Sanchez, Marie; Burwinkel, Barbara; Marme, Frederik; Schneeweiss, Andreas; Sohn, Christof; Wu, Anna H; Tseng, Chiu-Chen; Van Den Berg, David; Stram, Daniel O; Benitez, Javier; Zamora, M Pilar; Perez, Jose Ignacio Arias; Menéndez, Primitiva; Shu, Xiao-Ou; Lu, Wei; Gao, Yu-Tang; Cai, Qiuyin; Cox, Angela; Cross, Simon S; Reed, Malcolm W R; Andrulis, Irene L; Knight, Julia A; Glendon, Gord; Tchatchou, Sandrine; Sawyer, Elinor J; Tomlinson, Ian; Kerin, Michael J; Miller, Nicola; Haiman, Christopher A; Henderson, Brian E; Schumacher, Fredrick; Le Marchand, Loic; Lindblom, Annika; Margolin, Sara; Teo, Soo Hwang; Yip, Cheng Har; Lee, Daphne S C; Wong, Tien Y; Hooning, Maartje J; Martens, John W M; Collée, J Margriet; van Deurzen, Carolien H M; Hopper, John L; Southey, Melissa C; Tsimiklis, Helen; Kapuscinski, Miroslav K; Shen, Chen-Yang; Wu, Pei-Ei; Yu, Jyh-Cherng; Chen, Shou-Tung; Alnæs, Grethe Grenaker; Borresen-Dale, Anne-Lise; Giles, Graham G; Milne, Roger L; McLean, Catriona; Muir, Kenneth; Lophatananon, Artitaya; Stewart-Brown, Sarah; Siriwanarangsan, Pornthep; Hartman, Mikael; Miao, Hui; Buhari, Shaik Ahmad Bin Syed; Teo, Yik Ying; Fasching, Peter A; Haeberle, Lothar; Ekici, Arif B; Beckmann, Matthias W; Brenner, Hermann; Dieffenbach, Aida Karina; Arndt, Volker; Stegmaier, Christa; Swerdlow, Anthony; Ashworth, Alan; Orr, Nick; Schoemaker, Minouk J; García-Closas, Montserrat; Figueroa, Jonine; Chanock, Stephen J; Lissowska, Jolanta; Simard, Jacques; Goldberg, Mark S; Labrèche, France; Dumont, Martine; Winqvist, Robert; Pylkäs, Katri; Jukkola-Vuorinen, Arja; Brauch, Hiltrud; Brüning, Thomas; Koto, Yon-Dschun; Radice, Paolo; Peterlongo, Paolo; Bonanni, Bernardo; Volorio, Sara; Dörk, Thilo; Bogdanova, Natalia V; Helbig, Sonja; Mannermaa, Arto; Kataja, Vesa; Kosma, Veli-Matti; Hartikainen, Jaana M; Devilee, Peter; Tollenaar, Robert A E M; Seynaeve, Caroline; Van Asperen, Christi J; Jakubowska, Anna; Lubinski, Jan; Jaworska-Bieniek, Katarzyna; Durda, Katarzyna; Slager, Susan; Toland, Amanda E; Ambrosone, Christine B; Yannoukakos, Drakoulis; Sangrajrang, Suleeporn; Gaborieau, Valerie; Brennan, Paul; McKay, James; Hamann, Ute; Torres, Diana; Zheng, Wei; Long, Jirong; Anton-Culver, Hoda; Neuhausen, Susan L; Luccarini, Craig; Baynes, Caroline; Ahmed, Shahana; Maranian, Mel; Healey, Catherine S; González-Neira, Anna; Pita, Guillermo; Alonso, M Rosario; Alvarez, Nuria; Herrero, Daniel; Tessier, Daniel C; Vincent, Daniel; Bacot, Francois; de Santiago, Ines; Carroll, Jason; Caldas, Carlos; Brown, Melissa A; Lupien, Mathieu; Kristensen, Vessela N; Pharoah, Paul D P; Chenevix-Trench, Georgia; French, Juliet D; Easton, Douglas F; Dunning, Alison M

    2014-09-23

    GWAS have identified a breast cancer susceptibility locus on 2q35. Here we report the fine mapping of this locus using data from 101,943 subjects from 50 case-control studies. We genotype 276 SNPs using the 'iCOGS' genotyping array and impute genotypes for a further 1,284 using 1000 Genomes Project data. All but two, strongly correlated SNPs (rs4442975 G/T and rs6721996 G/A) are excluded as candidate causal variants at odds against >100:1. The best functional candidate, rs4442975, is associated with oestrogen receptor positive (ER+) disease with an odds ratio (OR) in Europeans of 0.85 (95% confidence interval=0.84-0.87; P=1.7 × 10(-43)) per t-allele. This SNP flanks a transcriptional enhancer that physically interacts with the promoter of IGFBP5 (encoding insulin-like growth factor-binding protein 5) and displays allele-specific gene expression, FOXA1 binding and chromatin looping. Evidence suggests that the g-allele confers increased breast cancer susceptibility through relative downregulation of IGFBP5, a gene with known roles in breast cell biology.

  15. DNA and RNA Quadruplex-Binding Proteins

    Directory of Open Access Journals (Sweden)

    Václav Brázda

    2014-09-01

    Full Text Available Four-stranded DNA structures were structurally characterized in vitro by NMR, X-ray and Circular Dichroism spectroscopy in detail. Among the different types of quadruplexes (i-Motifs, minor groove quadruplexes, G-quadruplexes, etc., the best described are G-quadruplexes which are featured by Hoogsteen base-paring. Sequences with the potential to form quadruplexes are widely present in genome of all organisms. They are found often in repetitive sequences such as telomeric ones, and also in promoter regions and 5' non-coding sequences. Recently, many proteins with binding affinity to G-quadruplexes have been identified. One of the initially portrayed G-rich regions, the human telomeric sequence (TTAGGGn, is recognized by many proteins which can modulate telomerase activity. Sequences with the potential to form G-quadruplexes are often located in promoter regions of various oncogenes. The NHE III1 region of the c-MYC promoter has been shown to interact with nucleolin protein as well as other G-quadruplex-binding proteins. A number of G-rich sequences are also present in promoter region of estrogen receptor alpha. In addition to DNA quadruplexes, RNA quadruplexes, which are critical in translational regulation, have also been predicted and observed. For example, the RNA quadruplex formation in telomere-repeat-containing RNA is involved in interaction with TRF2 (telomere repeat binding factor 2 and plays key role in telomere regulation. All these fundamental examples suggest the importance of quadruplex structures in cell processes and their understanding may provide better insight into aging and disease development.

  16. Acyl-CoA-binding protein/diazepam-binding inhibitor gene and pseudogenes

    DEFF Research Database (Denmark)

    Mandrup, S; Hummel, R; Ravn, S

    1992-01-01

    Acyl-CoA-binding protein (ACBP) is a 10 kDa protein isolated from bovine liver by virtue of its ability to bind and induce the synthesis of medium-chain acyl-CoA esters. Surprisingly, it turned out to be identical to a protein named diazepam-binding Inhibitor (DBI) claimed to be an endogenous mod...

  17. Nuclear FAK and Runx1 Cooperate to Regulate IGFBP3, Cell-Cycle Progression, and Tumor Growth.

    Science.gov (United States)

    Canel, Marta; Byron, Adam; Sims, Andrew H; Cartier, Jessy; Patel, Hitesh; Frame, Margaret C; Brunton, Valerie G; Serrels, Bryan; Serrels, Alan

    2017-08-14

    Nuclear focal adhesion kinase (FAK) is a potentially important regulator of gene expression in cancer, impacting both cellular function and the composition of the surrounding tumor microenvironment. Here, we report in a murine model of skin squamous cell carcinoma (SCC) that nuclear FAK regulates Runx1-dependent transcription of insulin-like growth factor binding protein 3 (IGFBP3), and that this regulates SCC cell-cycle progression and tumor growth in vivo Furthermore, we identified a novel molecular complex between FAK and Runx1 in the nucleus of SCC cells and showed that FAK interacted with a number of Runx1-regulatory proteins, including Sin3a and other epigenetic modifiers known to alter Runx1 transcriptional function through posttranslational modification. These findings provide important new insights into the role of FAK as a scaffolding protein in molecular complexes that regulate gene transcription. Cancer Res; 77(19); 1-12. ©2017 AACR. ©2017 American Association for Cancer Research.

  18. Characterization,tissue distribution and growth regulation of ghrs and igfbp1 in silver pomfret (Pampus argenteus)in handling stress%银鲳ghr和igfbp1基因表达特征、组织分布及操作胁迫对其的影响

    Institute of Scientific and Technical Information of China (English)

    孙鹏; 尹飞; 王建建; 李云航

    2016-01-01

    为探讨急性操作胁迫对银鲳生长的影响,首次克隆了3种生长调控相关基因-生长激素受体1(ghr1)、生长激素受体2(ghr2)和胰岛素样受体1(igfbp1),并对3种基因在银鲳肝脏、心脏、性腺、肌肉和肾脏等不同组织中的表达进行了比较。定量表达结果表明3种基因均广泛分布于所研究的各个组织中,而其中肾脏、性腺和心脏中的表达量较其它组织低。在银鲳受到外界操作胁迫刺激后,3种基因呈现不同的表达模式:其中 ghr2和 igfbp1的表达下调,而 ghr2的表达量与对照组无显著性差异。结果表明,ghr2和 igfbp1在银鲳生长调节中起到重要的作用;在胁迫环境中,外界刺激可通过下调生长相关基因表达以影响鱼体的生长。%Growth activities are mainly involved by growth hormone /insulin-like growth factors (GH/IGF) axis.GH and IGF are anabolic hormones,which increase muscle mass by stimulating protein synthesis and /or inhibiting protein breakdown.In fish,growth hormone receptor genes (ghrs)encode transmembrane receptor protein for GH.By binding GH,it can activate an intra-and intercellular signal transduction pathway leading to growth.Type 1 insulin-like growth factor-binding protein is encoded by igfbp1 gene,a member of igfbp family.Binding of this protein can prolong the half-life of IGFs and alter their interaction with cell surface receptors.Silver pomfret (Pampus argenteus)is an important commercial fish which has a wide distribution from the Arabian Gulf,the India Ocean and the East China Sea to Southeast Asia.Relevant artificial breeding techniques and P.argenteus reproductive biology have been studied in China and Kuwait since the 1980s. Due to its sensitivity to many kinds of stress factors,low growth rate and high mortality has been found in P. argenteus during culture practices.However,little is known about its molecular aspects,including gene expression information of

  19. Cobalamin and its binding protein in rat milk

    DEFF Research Database (Denmark)

    Raaberg, Lasse; Nexø, Ebba; Poulsen, Steen Seier

    1989-01-01

    Cobalamin and its binding protein, haptocorrin, are present in rat milk throughout the lactation period. The concentration of cobalamin is approximately 0.3-times the concentration of the unsaturated binding protein. The concentration of the unsaturated cobalamin-binding protein varies between 18...... nmol l-1 and 16 nmol l-1. The binding protein has a Stokes radius of 2.49 nm when saturated with cobalamin and 2.61 nm when unsaturated. It binds cobalamin over a broad range of pH and is able to bind cobinamide also. With immunohistochemistry, we find haptocorrin immunoreactivity in the mammary glands...

  20. Mechanical unfolding of ribose binding protein and its comparison with other periplasmic binding proteins.

    Science.gov (United States)

    Kotamarthi, Hema Chandra; Narayan, Satya; Ainavarapu, Sri Rama Koti

    2014-10-01

    Folding and unfolding studies on large, multidomain proteins are still rare despite their high abundance in genomes of prokaryotes and eukaryotes. Here, we investigate the unfolding properties of a 271 residue, two-domain ribose binding protein (RBP) from the bacterial periplasm using single-molecule force spectroscopy. We observe that RBP predominately unfolds via a two-state pathway with an unfolding force of ∼80 pN and an unfolding contour length of ∼95 nm. Only a small population (∼15%) of RBP follows three-state pathways. The ligand binding neither increases the mechanical stability nor influences the unfolding flux of RBP through different pathways. The kinetic partitioning between two-state and three-state pathways, which has been reported earlier for other periplasmic proteins, is also observed in RBP, albeit to a lesser extent. These results provide important insights into the mechanical stability and unfolding processes of large two-domain proteins and highlight the contrasting features upon ligand binding. Protein structural topology diagrams are used to explain the differences in the mechanical unfolding behavior of RBP with other periplasmic binding proteins.

  1. Effects of dynamic exercise on circulating IGF-1 and IGFBP-3 levels in patients with rheumatoid arthritis or ankylosing spondylitis.

    Science.gov (United States)

    Karatay, Saliha; Yildirim, Kadir; Melikoglu, Meltem Alkan; Akcay, Fatih; Senel, Kazim

    2007-10-01

    This study was performed to determine the effects of short-term dynamic exercise on serum insulin-like growth factor-1 (IGF-1) and insulin-like growth factor binding protein-3 (IGFBP-3) levels in the patients with rheumatoid arthritis (RA) and ankylosing spondylitis (AS). Patients with RA or AS and healthy controls were recruited. Dynamic treadmill exercise therapy was accomplished for 20 min/session with all of the participants. There were five sessions per week for 2 weeks. Morning stiffness duration, body pain, Stanford health assessment questionnaire, Ritchie articular index, Bath ankylosing spondylitis disease activity index (BASDAI), and Bath ankylosing spondylitis functional index (BASFI) were evaluated in the RA and AS patients. Laboratory assessments included: erythrocyte sedimentation rate, serum C-reactive protein, IGF-1, and IGFBP-3. Clinical and laboratory assessments were recorded at baseline and during exercise treatment on days 7 and 15. Twenty patients with RA, 15 with AS, and 14 healthy controls were included in this study. The pain evaluation, Ritchie, BASDAI, and BASFI scores were significantly improved by the exercise treatment in both patient groups. The important increases were found in circulating IGF-1 in RA (p exercise program in RA and AS patients. The increased IGF-1 may play an important role in the beneficial effects of dynamic exercise therapy in these patients.

  2. Methylation of insulin-like growth factor binding protein 3 gene in neonates with intrauterine growth restriction%胰岛素样生长因子结合蛋白3在宫内生长受限儿中的甲基化研究

    Institute of Scientific and Technical Information of China (English)

    苏爱玲; 蒋犁; 葛芹玉

    2011-01-01

    Objective To study the role of promoter methylation of insulin-like growth factor binding protein 3 (ICFBP3) in intrauterine growth restriction (IUGR). Methods Fifty neonates with IUCR and 30 healthy neonates were enrolled. The promoter methylation status of 1GFBP3 in peripheral blood was evaluated by methylation-specific PCR (MSP) and high resolution melting (HRM) techniques. Results The complete methylation rate, partial methylation rate and non-methylation rate of IGFBP3 promoter in the IUGR group was 4% (2/50) , 40% (20/50) and 56% (28/50) , respectively. The partial methylation rate and non-methylation rate of IGFBP3 promoter in the control group were 13% (4/30) and 87% (26/30) , respectively. There were significant differences in the promoter methylation rate of IGFBP3 between the two groups ( P < 0. 01 ). Conclusions The promoter methylation of IGFBP3 gene is associated with the pathogenesis of IUGR.%目的 探讨胰岛素样生长因子结合蛋白3(IGFBP3)启动子区甲基化状态在胎儿宫内生长受限(IUGR)中的作用.方法 选取IUGR新生儿50例及正常新生儿30例,应用甲基化特异性PCR(MSP)及高分辨率溶解(HRM)技术检测外周血中IGFBP3基因的甲基化状态.结果 IUGR组中IGFBP3启动子区完全甲基化比例为4%(2/50),部分甲基化比例为40%(20/50),未甲基化比例为56%(28/50);对照组中部分甲基化比例为13%(4/30),未甲基化比例为87%(26/30),两组甲基化率差异有统计学意义(P<0.01).结论 IGFBP3基因启动子区的甲基化程度与IUGR的发生有关.

  3. Discovery of a novel insulin-like peptide and insulin binding proteins in the Eastern rock lobster Sagmariasus verreauxi.

    Science.gov (United States)

    Chandler, Jennifer C; Aizen, Joseph; Elizur, Abigail; Hollander-Cohen, Lian; Battaglene, Stephen C; Ventura, Tomer

    2015-05-01

    This study reports, for the first time in any of the commercially important decapod species, the identification of an insulin-like peptide (ILP), distinct from the androgenic gland hormone. Bioinformatics analysis of the de novo assembled spiny lobster, (Sagmariasus verreauxi) transcriptome, allowed identification of Sv-ILP1 as well as eight binding proteins. Binding proteins were termed as Sv-IGFBP, due to homology with the vertebrate insulin-like growth-factor binding protein and Sv-SIBD1-7, single insulin-binding domain protein (SIBD), similar to those identified in other invertebrate species. Sv-ILP1 was found to be expressed in the eyestalk, gonads and antennal gland of both sexes and to a lesser extent in male muscle, androgenic gland and hepatopancreas. The expression profiles of each binding protein were found to vary across tissues, with Sv-SIBD5, 6 and 7 showing higher expression in the gonad, demonstrated by PCR and digital gene expression. Further spatial investigations, using in-situ hybridisation, found Sv-ILP1 to be expressed in the neurosecretory cells of the thoracic ganglia, in keeping with the tissue expression of Drosophila ILP7 (DILP7). This correlative tissue expression, considered with the phylogenetic clustering of Sv-ILP1 and DILP7, suggests Sv-ILP1 to be a DILP7 orthologue. The broad expression of Sv-ILP1 strongly suggests that ILPs have a role beyond that of masculinisation in decapods. The function of these novel peptides may have application in enhancing aquaculture practices in the commercially important decapod species. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Sequence Variations in the Bovine IGF-I and IGFBP3 Genes and Their Association with Growth and Development Traits in Chinese Beef Cattle

    Institute of Scientific and Technical Information of China (English)

    GAO Xue; SHI Ming-yan; XU Xiu-rong; LI Jun-ya; REN Hong-yan; XU Shang-zhong

    2009-01-01

    The objective of this study was to determine the genotype effects of the bovine insulin-like growth factor I (IGF-I) and its binding protein 3 (IGFBP3) genes on growth and development traits in beef cows,including 130 Chinese Simmental,42 Nanyang,and 47 Luxi Yellow cattle.Sequence variations in the bovine IGF-I and IGFBP3 genes were investigated by single strand conformation polymorphism (SSCP).SSCPs were detected in 6 fragments,which is the 5'-flanking region,the 2nd exon,the 5th exon,and the 5th intron of the IGF-I gene,and the 2nd exon,the 3rd exon of the IGFBP3 gene.Two polymorphisms,an A-to-G transition in the 2nd exon of the IGF-I gene and a T-to-C transition in the 2nd exon of IGFBP3 gene were detected in 3 breeds.The allele frequencies of 2 polymorphisms were 0.0411 (A),0.9589 (B),and 0.7237 (A),0.2763 (B),respectively.These 2 loci were analyzed to associate with body weight,height at withers,body length,heart girth,rump width,and beef production index (BPI) at 0,6,12,24,and 36-month old.The 1GFBP3 locus was shown to be associated with rump width,heart girth at 24-month and 36-month.Animals with BB genotype had higher rump width (24.86±0.47) cm at 24-month and (27.50±0.63) cm at 36-month.The heart girth was highest for the individuals with BB genotype (171.33±1.84) cm and higher than those with AB genotype (166.68±1.13) cm (P<0.05) at 36-month.

  5. Measuring Binding Affinity of Protein-Ligand Interaction Using Spectrophotometry: Binding of Neutral Red to Riboflavin-Binding Protein

    Science.gov (United States)

    Chenprakhon, Pirom; Sucharitakul, Jeerus; Panijpan, Bhinyo; Chaiyen, Pimchai

    2010-01-01

    The dissociation constant, K[subscript d], of the binding of riboflavin-binding protein (RP) with neutral red (NR) can be determined by titrating RP to a fixed concentration of NR. Upon adding RP to the NR solution, the maximum absorption peak of NR shifts to 545 nm from 450 nm for the free NR. The change of the absorption can be used to determine…

  6. Landscape of protein-small ligand binding modes.

    Science.gov (United States)

    Kasahara, Kota; Kinoshita, Kengo

    2016-09-01

    Elucidating the mechanisms of specific small-molecule (ligand) recognition by proteins is a long-standing conundrum. While the structures of these molecules, proteins and ligands, have been extensively studied, protein-ligand interactions, or binding modes, have not been comprehensively analyzed. Although methods for assessing similarities of binding site structures have been extensively developed, the methods for the computational treatment of binding modes have not been well established. Here, we developed a computational method for encoding the information about binding modes as graphs, and assessing their similarities. An all-against-all comparison of 20,040 protein-ligand complexes provided the landscape of the protein-ligand binding modes and its relationships with protein- and chemical spaces. While similar proteins in the same SCOP Family tend to bind relatively similar ligands with similar binding modes, the correlation between ligand and binding similarities was not very high (R(2)  = 0.443). We found many pairs with novel relationships, in which two evolutionally distant proteins recognize dissimilar ligands by similar binding modes (757,474 pairs out of 200,790,780 pairs were categorized into this relationship, in our dataset). In addition, there were an abundance of pairs of homologous proteins binding to similar ligands with different binding modes (68,217 pairs). Our results showed that many interesting relationships between protein-ligand complexes are still hidden in the structure database, and our new method for assessing binding mode similarities is effective to find them.

  7. Identification of actin binding protein, ABP-280, as a binding partner of human Lnk adaptor protein.

    Science.gov (United States)

    He, X; Li, Y; Schembri-King, J; Jakes, S; Hayashi, J

    2000-08-01

    Human Lnk (hLnk) is an adaptor protein with multiple functional domains that regulates T cell activation signaling. In order to identify cellular Lnk binding partners, a yeast two-hybrid screening of human spleen cDNA library was carried out using human hLnk as bait. A polypeptide sequence identical to the C-terminal segment of the actin binding protein (ABP-280) was identified as a hLnk binding protein. The expressed hLnk and the FLAG tagged C-terminal 673 amino acid residues of ABP-280 or the endogenous ABP-280 in COS-7 cells could be co-immunoprecipitated using antibodies either to hLnk, FLAG or ABP-280, respectively. Furthermore, immunofluorescence confocal microscope showed that hLnk and ABP-280 co-localized at the plasma membrane and at juxtanuclear region of COS-7 cells. In Jurkat cells, the endogenous hLnk also associates with the endogenous ABP-280 indicating that the association of these two proteins is physiological. The interacting domains of both proteins were mapped using yeast two-hybrid assays. Our results indicate that hLnk binds to the residues 2006-2454 (repeats 19-23C) of ABP-280. The domain in hLnk that associates with ABP-280 was mapped to an interdomain region of 56 amino acids between pleckstrin homology and Src homology 2 domains. These results suggest that hLnk may exert its regulatory role through its association with ABP-280.

  8. Effect of growth hormone on small intestinal homeostasis relation to cellular mediators IGF-I and IGFBP-3

    Institute of Scientific and Technical Information of China (English)

    Betul Ersoy; Kemal Ozbilgin; Erhun Kasirga; Sevinc Inan; Senol Coskun; Ibrahim Tuglu

    2009-01-01

    AIM: To evaluate the effects of growth hormone (GH) on the histology of small intestines which might be related to the role of insulin like growth factor (IGF)-I, IGF-binding protein 3 (IGFBP-3) and its receptors.METHODS: Twelve week-old adult male Wistar albino rats were divided into two groups.The study group ( n = 10), received recombinant human growth hormone (rGH) at a dose of 2 mg/kg per day subcutaneously for 14 d and the control group ( n = 10) received physiologic serum.Paraffin sections of jejunum were stained with periodic acid shift (PAS) and hematoxylin and eosin (HE) for light microscopy.They were also examined for IGF-I, IGFBP-3 and IGF-receptor immunoreactivities.Staining intensity was graded semi-quantitatively using the HSCORE.RESULTS: Goblet cells and the cells in crypt epithelia were significantly increased in the study group compared to that of the control group.We have demonstrated an increase of IGF-I and IGFBP-3 immunoreactivities in surface epithelium of the small intestine by GH application.IGF-I receptor immunoreactivities of crypt, villous columnar cells, enteroendocrine cells and muscularis mucosae were also more strongly positive in the study group compared to those of in the control group.CONCLUSION: These findings confirm the important trophic and protective role of GH in the homeostasis of the small intestine.The trophic effect is mediated by an increase in IGF-I synthesis in the small intestine, but the protective effect is not related to IGF-I.

  9. Genetic polymorphisms in IGF-I and IGFBP-3 are associated with prostate cancer in the Chinese population.

    Directory of Open Access Journals (Sweden)

    Jian Qian

    Full Text Available Insulin-like growth factor-I (IGF-I and IGF binding protein-3 (IGFBP-3 are members of the insulin-like growth factor (IGF family that play important roles in carcinogenesis. We hypothesized that the functional polymorphisms in IGF-I and IGFBP-3 may be associated with the risk of prostate cancer (PCa in the Chinese population. This hospital-based case-control study included 664 PCa patients and 702 cancer-free controls. Nine SNPs in IGF-I and IGFBP-3 were genotyped using the TaqMan assay. The genetic associations between the pathogenesis and progression of PCa were assessed by logistic regression. We found that the genotype and allele frequency distribution of rs6218, rs35767 and rs5742612 were significantly different when comparing PCa cases to controls (P  = 0.005, 0.005 and 0.020, respectively. In the combined analysis, individuals with 2-6 risk alleles had an elevated risk of PCa compared to those with 0-1 risk alleles. We also found that the association between the combined risk alleles and the risk of PCa appeared stronger in the following subgroups: individuals older than 71 years of age (OR  = 1.41, 95%CI  = 1.05-1.91, P  = 0.020, nonsmokers (OR  = 1.68, 95%CI  = 1.21-2.32, P  = 0.002, nondrinkers (OR  = 1.32, 95%CI  = 1.02-1.61, P  = 0.002, and those with a negative family history of PCa (OR  = 1.28, 95%CI  = 1.02-1.71, P  = 0.022. Our results indicate that the three SNPs (rs6218, rs35767 and rs5742612 and the joint genotypes with 2-6 risk alleles, may contribute to the susceptibility to PCa, but not the progression, in the Chinese population.

  10. The PRB-dependent FOXO1/IGFBP-1 axis is essential for progestin to inhibit endometrial epithelial growth.

    Science.gov (United States)

    Nakamura, Mitsuhiro; Takakura, Masahiro; Fujii, Reina; Maida, Yoshiko; Bono, Yukiko; Mizumoto, Yasunari; Zhang, Xian; Kiyono, Tohru; Kyo, Satoru

    2013-08-01

    Progestin inhibits the growth of normal and cancerous endometria via the progesterone receptor (PR), but the distinct functions and signalings of PR subtypes have not been fully understood. The aim of the present study was to dissect the key pathways of progestin to inhibit endometrial epithelial growth. Immortalized endometrial epithelial cells (EM-E6/E7/TERT) with stable PRA or PRB expression were established and used for the experiments. In vitro growth inhibition by progestin was mainly observed in EM-E6/E7/TERT cells with PRB rather than those with PRA. RT-PCR assay confirmed that FOXO1, a key gene for progestin action, was up-regulated by progestin in a PRB-dependent manner. cDNA microarray analysis identified IGFBP-1, which contains FOXO1 binding sites on its promoter, to be induced by medroxyprogesterone acetate (MPA) in EM-E6/E7/TERT cells with PRB but not with PRA. siRNA knockdown of FOXO1 disturbed the induction of IGFBP-1 by MPA, while IGFBP-1 knockdown showed no effect on MPA-induced FOXO1 expression, indicating that FOXO1 is an upstream regulator of IGFBP-1. Luciferase reporter assays showed that MPA activated the IGFBP-1 promoter, which was cancelled by FOXO1 knockdown. Chromatin immunoprecipitation assay confirmed the in vivo binding of FOXO1 to the core promoter of IGFBP-1. IGFBP-1 knockdown significantly attenuated the growth inhibitory effects of MPA. The FOXO1/IGFBP-1 axis is essential for PRB-dependent growth inhibition of endometrial epithelial cells, offering a potential therapeutic clue to enhance the progestin effect.

  11. Stimulation of the 150-kilodalton insulin-like growth factor-binding protein-3 ternary complex by continuous and pulsatile patterns of growth hormone (GH) administration in GH-deficient patients

    DEFF Research Database (Denmark)

    Laursen, Torben; Flyvbjerg, Allan; Jørgensen, Jens Otto Lunde

    2000-01-01

    Abstract In the circulation insulin-like growth factor I (IGF-I), IGF-binding protein 3 (IGFBP-3), and the acid-labile subunit (ALS) form a 150-kDa ternary complex that is of importance for the regulation of IGF-I bioactivity. GH administration is known to increase each of the single components...... of the ternary complex, and in GH-deficient rats formation of the 150-kDa complex is induced more by continuous than by pulsatile GH patterns. The aim of the present studies was to study the effects of the GH administration pattern on the formation of the 150-kDa ternary complex in humans. A fixed total GH dose...... (2 IU/m2-24 h) was administered iv randomly as 1) continuous infusion or 2) eight bolus injections to five GH-deficient patients over a period of 24 h. GH administration significantly increased serum IGF-I and IGFBP-3 levels and the IGF-I/IGFBP-3 ratio. IGF-I levels increased most pronouncedly after...

  12. Preliminary investigation of the relationship between plasma IGFBP-6 concetration and pathological grading and prognosis in patients with cerebral gliomas%胶质瘤患者血浆IGFBP-6浓度与病理分级及预后关系的初步探讨

    Institute of Scientific and Technical Information of China (English)

    张国珍; 林毅; 江涛; 王江飞

    2014-01-01

    目的:检测胶质瘤患者血浆中IGFBP-6的浓度,探讨其作为临床预测脑胶质瘤生存期标志物的可能性。方法:用酶联免疫吸附法(ELIISA)检测207例不同级别胶质瘤患者和36例正常对照者的血浆IGFBP6水平。采用方差分析(analysis of variance,ANOVA)比较胶质瘤患者与正常对照组及不同分级的胶质瘤患者的血浆IGFBP6水平,及对中位生存期的影像。结果:(1)低级别胶质瘤(Ⅱ级)患者血浆IGFBP-6平均水平(154.95±43.02ng/mL)较正常对照组(188.77±59.57ng/mL)明显降低(P<0.05),亦明显低于高级别胶质瘤(Ⅲ,Ⅳ级)(183.14.95±71.43ng/mL)(P<0.05),而高级别胶质瘤和正常对照之间无显著性差异。(2)Ⅲ级胶质瘤患者低血浆IGFBP6水平组生存期均值为711天(中位生存期,788天,95%CI,618-805)与高血浆IGFBP6水平组577天(中位生存期,607天,95%CI,510-644)相比有显著统计学差异(P<0.001)。结论:血浆IGFBP-6水平具有成为脑胶质瘤标记物的潜质,可能作为一个生物标记物来预测患者的生存期。%Objective:To investigate the possibility of insulin-like growth factor binding protein 6(IGFBP6) as a po-tential prognosis predicator in the patients with cerebral glioma and the pathological grading value of its plasma concentra-tion. Methods:IGFBP-6 ELISA kit was used to measure the plasma IGFBP-6 concetrtion of 207 patients who had been newly diagnosed with cerebral glioma and 36 healthy volunteers. Grade Ⅲ glioma patients whose pathological tissue con-tained astrocytoma were compared. Results:(1)The preoperative plasma IGFBP-6 levels could significantly discriminate the surviwal of the two grade Ⅲ glioma subgroups ,with a mean survival time of 711days (the mean survival time, 788days, 95%CI,618-805) in low plasma IGFBP-6 level group versus mean survival time of 577days (the mean survival time, 607days,95%CI,510-644) in high plasma level group(P<0

  13. Comparison of the Folding Mechanism of Highly Homologous Proteins in the Lipid-binding Protein Family

    Science.gov (United States)

    The folding mechanism of two closely related proteins in the intracellular lipid binding protein family, human bile acid binding protein (hBABP) and rat bile acid binding protein (rBABP) were examined. These proteins are 77% identical (93% similar) in sequence Both of these singl...

  14. Comparison of the Folding Mechanism of Highly Homologous Proteins in the Lipid-binding Protein Family

    Science.gov (United States)

    The folding mechanism of two closely related proteins in the intracellular lipid binding protein family, human bile acid binding protein (hBABP) and rat bile acid binding protein (rBABP) were examined. These proteins are 77% identical (93% similar) in sequence Both of these singl...

  15. Assessing the role of insulin‐like growth factors and binding proteins in prostate cancer using Mendelian randomization: Genetic variants as instruments for circulating levels

    Science.gov (United States)

    Bonilla, Carolina; Lewis, Sarah J.; Rowlands, Mari‐Anne; Gaunt, Tom R.; Davey Smith, George; Gunnell, David; Palmer, Tom; Donovan, Jenny L.; Hamdy, Freddie C.; Neal, David E.; Eeles, Rosalind; Easton, Doug; Kote‐Jarai, Zsofia; Al Olama, Ali Amin; Benlloch, Sara; Muir, Kenneth; Giles, Graham G.; Wiklund, Fredrik; Grönberg, Henrik; Haiman, Christopher A.; Schleutker, Johanna; Nordestgaard, Børge G.; Travis, Ruth C.; Pashayan, Nora; Khaw, Kay‐Tee; Stanford, Janet L.; Blot, William J.; Thibodeau, Stephen; Maier, Christiane; Kibel, Adam S; Cybulski, Cezary; Cannon‐Albright, Lisa; Brenner, Hermann; Park, Jong; Kaneva, Radka; Batra, Jyotsna; Teixeira, Manuel R.; Pandha, Hardev; Lathrop, Mark; Holly, Jeff M. P.

    2016-01-01

    Circulating insulin‐like growth factors (IGFs) and their binding proteins (IGFBPs) are associated with prostate cancer. Using genetic variants as instruments for IGF peptides, we investigated whether these associations are likely to be causal. We identified from the literature 56 single nucleotide polymorphisms (SNPs) in the IGF axis previously associated with biomarker levels (8 from a genome‐wide association study [GWAS] and 48 in reported candidate genes). In ∼700 men without prostate cancer and two replication cohorts (N ∼ 900 and ∼9,000), we examined the properties of these SNPS as instrumental variables (IVs) for IGF‐I, IGF‐II, IGFBP‐2 and IGFBP‐3. Those confirmed as strong IVs were tested for association with prostate cancer risk, low (< 7) vs. high (≥ 7) Gleason grade, localised vs. advanced stage, and mortality, in 22,936 controls and 22,992 cases. IV analysis was used in an attempt to estimate the causal effect of circulating IGF peptides on prostate cancer. Published SNPs in the IGFBP1/IGFBP3 gene region, particularly rs11977526, were strong instruments for IGF‐II and IGFBP‐3, less so for IGF‐I. Rs11977526 was associated with high (vs. low) Gleason grade (OR per IGF‐II/IGFBP‐3 level‐raising allele 1.05; 95% CI: 1.00, 1.10). Using rs11977526 as an IV we estimated the causal effect of a one SD increase in IGF‐II (∼265 ng/mL) on risk of high vs. low grade disease as 1.14 (95% CI: 1.00, 1.31). Because of the potential for pleiotropy of the genetic instruments, these findings can only causally implicate the IGF pathway in general, not any one specific biomarker. PMID:27225428

  16. Order effects of combined strength and endurance training on testosterone, cortisol, growth hormone, and IGF-1 binding protein 3 in concurrently trained men.

    Science.gov (United States)

    Rosa, Claudio; Vilaça-Alves, José; Fernandes, Helder M; Saavedra, Francisco J; Pinto, Ronei S; dos Reis, Victor M

    2015-01-01

    Concurrent training (CT) has been widely used in fitness centers to simultaneously optimize cardiovascular and neuromuscular fitness, and induce a high-energy expenditure. Therefore, the aim of this study was to compare the acute effects of 2 different orders of CT on hormonal responses in concurrently trained men. Fourteen men (mean ± SD: 24.7 ± 5.1 years) were randomly divided into 2 groups: endurance training followed by strength (ES, n = 7) and strength training followed by endurance (SE, n = 7). Serum concentrations of testosterone, cortisol, growth hormone, and IGF-1 binding protein 3 (IGFBP-3) were measured before and after both training orders. A significant interaction between exercise order and time was only found in the IGFBP-3 levels (p = 0.022). The testosterone and IGFBP-3 concentrations significantly increased in the ES group after the exercise trainings (57.7 ± 35.1%, p = 0.013 and 17.0 ± 15.5%, p = 0.032, respectively) but did not change significantly in the SE group (15.5 ± 36.6%, p = 0.527 and -4.2 ± 13.9%, p = 0.421, respectively). Conversely, cortisol and growth hormone concentrations significantly increased in both ES (169.2 ± 191.0%, p = 0.021 and 13,296.8 ± 13,009.5%, p = 0.013, respectively) and SE (92.2 ± 81.5%, p = 0.017 and 12,346.2 ± 9714.1%, p = 0.001, respectively) groups compared with baseline values. No significant correlations were found between the changes in the hormonal concentrations. In conclusion, these results suggest that immediately postexercise testosterone and IGFPB-3 responses are significantly increased only after the ES order. Therefore, an ES training order should be prescribed if the main focus of the training intervention is to induce an acute postexercise anabolic environment.

  17. Skp2B overexpression alters a prohibitin-p53 axis and the transcription of PAPP-A, the protease of insulin-like growth factor binding protein 4.

    Directory of Open Access Journals (Sweden)

    Harish Chander

    Full Text Available BACKGROUND: We previously reported that the degradation of prohibitin by the SCF(Skp2B ubiquitin ligase results in a defect in the activity of p53. We also reported that MMTV-Skp2B transgenic mice develop mammary gland tumors that are characterized by an increased proteolytic cleavage of the insulin-like growth factor binding protein 4 (IGFBP-4, an inhibitor of IGF signaling. However, whether a link exists between a defect in p53 activity and proteolysis of IGFBP-4 was not established. METHODS AND RESULTS: We analyzed the levels of pregnancy-associated plasma protein A (PAPP-A, the protease of IGFBP-4, in MMTV-Skp2B transgenic mice and found that PAPP-A levels are elevated. Further, we found a p53 binding site in intron 1 of the PAPP-A gene and that both wild type and mutant p53 bind to this site. However, binding of wild type p53 results in the transcriptional repression of PAPP-A, while binding of mutant p53 results in the transcriptional activation of PAPP-A. Since MMTV-Skp2B mice express wild type p53 and yet show elevated levels of PAPP-A, at first, these observations appeared contradictory. However, further analysis revealed that the defect in p53 activity in Skp2B overexpressing cells does not only abolish the activity of wild type of p53 but actually mimics that of mutant p53. Our results suggest that in absence of prohibitin, the half-life of p53 is increased and like mutant p53, the conformation of p53 is denatured. CONCLUSIONS: These observations revealed a novel function of prohibitin as a chaperone of p53. Further, they suggest that binding of denatured p53 in intron 1 causes an enhancer effect and increases the transcription of PAPP-A. Therefore, these findings indicate that the defect in p53 function and the increased proteolysis of IGFBP-4, we had observed, represent two components of the same pathway, which contributes to the oncogenic function of Skp2B.

  18. Vitamin D Binding Protein and Bone Health

    Directory of Open Access Journals (Sweden)

    Ishir Bhan

    2014-01-01

    Full Text Available Vitamin D binding protein (DBP is the major carrier protein of 25-hydroxyvitamin D (25(OH D in the circulation, where it may serve roles in maintaining stable levels during times of decreased 25(OH availability and in regulating delivery of 25(OH D to target tissues. Several genetic polymorphisms of DBP have been described that lead to phenotypic changes in the protein that may affect affinity, activity, and concentration. These polymorphisms have been linked with alterations in bone density in several populations. One of the mechanisms by which DBP may alter bone health involves regulating vitamin D bioavailability. DBP-bound vitamin is thought to be relatively unavailable to target tissues, and thus alterations in DBP levels or affinity could lead to changes in vitamin D bioactivity. As a result, functional vitamin D status may differ greatly between individuals with similar total 25(OH D levels. Additionally, DBP may have independent roles on macrophage and osteoclast activation. This review will summarize recent findings about DBP with respect to measures of bone density and health.

  19. Neuronal calcium-binding proteins and schizophrenia.

    Science.gov (United States)

    Eyles, D W; McGrath, J J; Reynolds, G P

    2002-09-01

    Calcium-binding proteins (CBPs) such as calbindin, parvalbumin and calretinin are used as immunohistochemical markers for discrete neuronal subpopulations. They are particularly useful in identifying the various subpopulations of GABAergic interneurons that control output from prefrontal and cingulate cortices as well as from the hippocampus. The strategic role these interneurons play in regulating output from these three crucial brain regions has made them a focus for neuropathological investigation in schizophrenia. The number of pathological reports detailing subtle changes in these CBP-containing interneurons in patients with schizophrenia is rapidly growing. These proteins however are more than convenient neuronal markers. They confer survival advantages to neurons and can increase the neuron's ability to sustain firing. These properties may be important in the subtle pathophysiology of nondegenerative phenomena such as schizophrenia. The aim of this review is to introduce the reader to the functional properties of CBPs and to examine the emerging literature reporting alterations in these proteins in schizophrenia as well as draw some conclusions about the significance of these findings.

  20. Glycan masking of Plasmodium vivax Duffy Binding Protein for probing protein binding function and vaccine development.

    Directory of Open Access Journals (Sweden)

    Sowmya Sampath

    Full Text Available Glycan masking is an emerging vaccine design strategy to focus antibody responses to specific epitopes, but it has mostly been evaluated on the already heavily glycosylated HIV gp120 envelope glycoprotein. Here this approach was used to investigate the binding interaction of Plasmodium vivax Duffy Binding Protein (PvDBP and the Duffy Antigen Receptor for Chemokines (DARC and to evaluate if glycan-masked PvDBPII immunogens would focus the antibody response on key interaction surfaces. Four variants of PVDBPII were generated and probed for function and immunogenicity. Whereas two PvDBPII glycosylation variants with increased glycan surface coverage distant from predicted interaction sites had equivalent binding activity to wild-type protein, one of them elicited slightly better DARC-binding-inhibitory activity than wild-type immunogen. Conversely, the addition of an N-glycosylation site adjacent to a predicted PvDBP interaction site both abolished its interaction with DARC and resulted in weaker inhibitory antibody responses. PvDBP is composed of three subdomains and is thought to function as a dimer; a meta-analysis of published PvDBP mutants and the new DBPII glycosylation variants indicates that critical DARC binding residues are concentrated at the dimer interface and along a relatively flat surface spanning portions of two subdomains. Our findings suggest that DARC-binding-inhibitory antibody epitope(s lie close to the predicted DARC interaction site, and that addition of N-glycan sites distant from this site may augment inhibitory antibodies. Thus, glycan resurfacing is an attractive and feasible tool to investigate protein structure-function, and glycan-masked PvDBPII immunogens might contribute to P. vivax vaccine development.

  1. Characterizing the morphology of protein binding patches.

    Science.gov (United States)

    Malod-Dognin, Noël; Bansal, Achin; Cazals, Frédéric

    2012-12-01

    Let the patch of a partner in a protein complex be the collection of atoms accounting for the interaction. To improve our understanding of the structure-function relationship, we present a patch model decoupling the topological and geometric properties. While the geometry is classically encoded by the atomic positions, the topology is recorded in a graph encoding the relative position of concentric shells partitioning the interface atoms. The topological-geometric duality provides the basis of a generic dynamic programming-based algorithm comparing patches at the shell level, which may favor topological or geometric features. On the biological side, we address four questions, using 249 cocrystallized heterodimers organized in biological families. First, we dissect the morphology of binding patches and show that Nature enjoyed the topological and geometric degrees of freedom independently while retaining a finite set of qualitatively distinct topological signatures. Second, we argue that our shell-based comparison is effective to perform atomic-level comparisons and show that topological similarity is a less stringent than geometric similarity. We also use the topological versus geometric duality to exhibit topo-rigid patches, whose topology (but not geometry) remains stable upon docking. Third, we use our comparison algorithms to infer specificity-related information amidst a database of complexes. Finally, we exhibit a descriptor outperforming its contenders to predict the binding affinities of the affinity benchmark. The softwares developed with this article are availablefrom http://team.inria.fr/abs/vorpatch_compatch/.

  2. Mitogenic properties of insulin-like growth factors I and II, insulin-like growth factor binding protein-3 and epidermal growth factor on human breast epithelial cells in primary culture.

    Science.gov (United States)

    Strange, Karen S; Wilkinson, Darcy; Emerman, Joanne T

    2002-10-01

    Insulin-like growth factor-I (IGF-I) and insulin-like growth factor-II (IGF-II) are growth factors implicated in mammary gland development and are believed to be involved in breast cancer. However, the interactions between components of the IGF system and breast epithelial cells, which give rise to breast cancer, are not well understood. We have investigated the mitogenic properties of IGF-I, IGF-II, IGF binding protein-3 (IGFBP-3) and epidermal growth factor (EGF) on human breast epithelial cells (HBEC) in primary culture. We show that, under serum-free conditions, HBEC are stimulated to grow in response to IGF-I and IGF-II in a dose-dependent manner. IGF-I and EGF, a potent stimulator of HBEC growth in primary culture and also associated with breast cancer, appear to stimulate HBEC in a synergistic manner. IGFBP-3 inhibits the stimulation by IGF-I, IGF-II and IGF-I plus EGE In addition, it appears that IGFBP-3 has an inhibitory effect on HBEC growth that is IGF-independent. This study is the first to address the effects of IGF-I, IGF-II and IGFBP-3 alone and in combination with EGF on HBEC growth in primary culture. Characterizing the role of the IGF system in normal breast biology is significant because the system has been implicated in breast cancer and a number of the anti-estrogens used in treatment are believed to function through the IGF system.

  3. The Plasminogen-Binding Group A Streptococcal M Protein-Related Protein Prp Binds Plasminogen via Arginine and Histidine Residues▿

    OpenAIRE

    Martina L. Sanderson-Smith; Dowton, Mark; Ranson, Marie; Walker, Mark J.

    2006-01-01

    The migration of the human pathogen Streptococcus pyogenes (group A streptococcus) from localized to deep tissue sites may result in severe invasive disease, and sequestration of the host zymogen plasminogen appears crucial for virulence. Here, we describe a novel plasminogen-binding M protein, the plasminogen-binding group A streptococcal M protein (PAM)-related protein (Prp). Prp is phylogenetically distinct from previously described plasminogen-binding M proteins of group A, C, and G strep...

  4. Angiopoietin-like 5 and IGFBP2 stimulate ex vivo expansion of human cord blood hematopoietic stem cells as assayed by NOD/SCID transplantation.

    Science.gov (United States)

    Zhang, Cheng Cheng; Kaba, Megan; Iizuka, Satoru; Huynh, HoangDinh; Lodish, Harvey F

    2008-04-01

    Hematopoietic stem cells (HSCs) are the basis of bone marrow transplantation and are attractive target cells for hematopoietic gene therapy, but these important clinical applications have been severely hampered by difficulties in ex vivo expansion of HSCs. In particular, the use of cord blood for adult transplantation is greatly limited by the number of HSCs. Previously we identified angiopoietin-like proteins and IGF-binding protein 2 (IGFBP2) as new hormones that, together with other factors, can expand mouse bone marrow HSCs in culture. Here, we measure the activity of multipotent human severe combined immunodeficient (SCID)-repopulating cells (SRCs) by transplantation into the nonobese diabetic SCID (NOD/SCID) mice; secondary transplantation was performed to evaluate the self-renewal potential of SRCs. A serum-free medium containing SCF, TPO, and FGF-1 or Flt3-L cannot significantly support expansion of the SRCs present in human cord blood CD133+ cells. Addition of either angiopoietin-like 5 or IGF-binding protein 2 to the cultures led to a sizable expansion of HSC numbers, as assayed by NOD/SCID transplantation. A serum-free culture containing SCF, TPO, FGF-1, angiopoietin-like 5, and IGFBP2 supports an approximately 20-fold net expansion of repopulating human cord blood HSCs, a number potentially applicable to several clinical processes including HSC transplantation.

  5. Methyl-CpG binding proteins in the nervous system

    Institute of Scientific and Technical Information of China (English)

    Guoping FAN; Leah HUTNICK

    2005-01-01

    Classical methyl-CpG binding proteins contain the conserved DNA binding motif methyl-cytosine binding domain (MBD), which preferentially binds to methylated CpG dinucleotides. These proteins serve as transcriptional repressors,mediating gene silencing via DNA cytosine methylation. Mutations in methyl-CpG binding protein 2 (MeCP2) have been linked to the human mental retardation disorder Rett syndrome, suggesting an important role for methyl-CpG binding proteins in brain development and function. This mini-review summarizes the recent advances in studying the diverse functions of MeCP2 as a prototype for other methyl-CpG binding proteins in the development and function of the vertebrate nervous system.

  6. ANDROGEN REGULATION OF PROSTATIC STEROID BINDING PROTEIN GENE TRANSCRIPTION

    Institute of Scientific and Technical Information of China (English)

    ZHANGYong-Lian; ZHOUZong-Xun; ZHANGYou-Duan; PARKERMalcolmG

    1989-01-01

    Prostatic steroid binding protein (PSBP) is a major protein secreted in the rat ventral prostate (V.P.) and also one of the components in seminal fluid, The potential importance of this protein in male fertility emerged from its ability of binding cholesterol which might modulate the proportion of phospholipids and cholesterol in sperm making it suitable

  7. STRUCTURAL FEATURES OF PLANT CHITINASES AND CHITIN-BINDING PROTEINS

    NARCIS (Netherlands)

    BEINTEMA, JJ

    1994-01-01

    Structural features of plant chitinases and chitin-binding proteins are discussed. Many of these proteins consist of multiple domains,of which the chitin-binding hevein domain is a predominant one. X-ray and NMR structures of representatives of the major classes of these proteins are available now,

  8. Protein function annotation by local binding site surface similarity.

    Science.gov (United States)

    Spitzer, Russell; Cleves, Ann E; Varela, Rocco; Jain, Ajay N

    2014-04-01

    Hundreds of protein crystal structures exist for proteins whose function cannot be confidently determined from sequence similarity. Surflex-PSIM, a previously reported surface-based protein similarity algorithm, provides an alternative method for hypothesizing function for such proteins. The method now supports fully automatic binding site detection and is fast enough to screen comprehensive databases of protein binding sites. The binding site detection methodology was validated on apo/holo cognate protein pairs, correctly identifying 91% of ligand binding sites in holo structures and 88% in apo structures where corresponding sites existed. For correctly detected apo binding sites, the cognate holo site was the most similar binding site 87% of the time. PSIM was used to screen a set of proteins that had poorly characterized functions at the time of crystallization, but were later biochemically annotated. Using a fully automated protocol, this set of 8 proteins was screened against ∼60,000 ligand binding sites from the PDB. PSIM correctly identified functional matches that predated query protein biochemical annotation for five out of the eight query proteins. A panel of 12 currently unannotated proteins was also screened, resulting in a large number of statistically significant binding site matches, some of which suggest likely functions for the poorly characterized proteins.

  9. DBD2BS: connecting a DNA-binding protein with its binding sites

    OpenAIRE

    2012-01-01

    By binding to short and highly conserved DNA sequences in genomes, DNA-binding proteins initiate, enhance or repress biological processes. Accurately identifying such binding sites, often represented by position weight matrices (PWMs), is an important step in understanding the control mechanisms of cells. When given coordinates of a DNA-binding domain (DBD) bound with DNA, a potential function can be used to estimate the change of binding affinity after base substitutions, where the changes c...

  10. Detection of secondary binding sites in proteins using fragment screening.

    Science.gov (United States)

    Ludlow, R Frederick; Verdonk, Marcel L; Saini, Harpreet K; Tickle, Ian J; Jhoti, Harren

    2015-12-29

    Proteins need to be tightly regulated as they control biological processes in most normal cellular functions. The precise mechanisms of regulation are rarely completely understood but can involve binding of endogenous ligands and/or partner proteins at specific locations on a protein that can modulate function. Often, these additional secondary binding sites appear separate to the primary binding site, which, for example for an enzyme, may bind a substrate. In previous work, we have uncovered several examples in which secondary binding sites were discovered on proteins using fragment screening approaches. In each case, we were able to establish that the newly identified secondary binding site was biologically relevant as it was able to modulate function by the binding of a small molecule. In this study, we investigate how often secondary binding sites are located on proteins by analyzing 24 protein targets for which we have performed a fragment screen using X-ray crystallography. Our analysis shows that, surprisingly, the majority of proteins contain secondary binding sites based on their ability to bind fragments. Furthermore, sequence analysis of these previously unknown sites indicate high conservation, which suggests that they may have a biological function, perhaps via an allosteric mechanism. Comparing the physicochemical properties of the secondary sites with known primary ligand binding sites also shows broad similarities indicating that many of the secondary sites may be druggable in nature with small molecules that could provide new opportunities to modulate potential therapeutic targets.

  11. Lipopolysaccharide binding protein in preterm infants

    Science.gov (United States)

    Behrendt, D; Dembinski, J; Heep, A; Bartmann, P

    2004-01-01

    Objective: To assess serum concentrations of lipopolysaccharide binding protein (LBP) in preterm infants with neonatal bacterial infection (NBI). Methods: Blood samples were analysed of 57 preterm (28+1 to 36+6, median 33+2 weeks gestation) and 17 term infants admitted to the neonatal intensive care unit within the first 72 hours of life with suspicion of NBI. Samples were obtained at first suspicion of sepsis and after 12 and 24 hours. Diagnosis of NBI was confirmed by raised concentrations of C reactive protein and/or interleukin 6. The influence of gestational age and labour was analysed. Results: Maximum LBP concentrations in infants with NBI were greatly increased compared with infants without NBI (13.0–46.0 µg/ml (median 20.0 µg/ml) v 0.6–17.4 µg/ml (median 4.2 µg/ml)). LBP concentrations in infected infants were not yet significantly raised when NBI was first suspected. The LBP concentrations of preterm infants were comparable to those of term infants. Regression analysis revealed no significant effect of labour or gestational age on LBP. Conclusions: Raised LBP concentrations indicate NBI in preterm and term infants. Preterm infants of > 28 weeks gestation seem to be capable of producing LBP as efficiently as term infants. Neonatal LBP concentrations are not influenced by labour. LBP may be a useful diagnostic marker of NBI in preterm infants. PMID:15499153

  12. Abnormal IGF-Binding Protein Profile in the Bone Marrow of Multiple Myeloma Patients

    DEFF Research Database (Denmark)

    Bieghs, Liesbeth; Brohus, Malene; Kristensen, Ida B

    2016-01-01

    ), monoclonal gammopathy of undetermined significance (MGUS) (n = 37), and control individuals (n = 15), using ELISA (IGFs) and 125I-IGF1 Western Ligand Blotting (IGFBPs). MGUS and MM patients displayed a significant increase in intact IGFBP-2 (2.5-3.8 fold) and decrease in intact IGFBP-3 (0.6-0.5 fold......) in the circulation compared to control individuals. Further, IGFBP-2 as well as total IGFBP levels were significantly lower in bone marrow compared to circulation in MM and MGUS only, whereas IGF1, IGF2, and IGFBP-3 were equally distributed between the two compartments. In conclusion, the profound change in IGFBP...

  13. Solution Structure and Backbone Dynamics of Human Liver Fatty Acid Binding Protein: Fatty Acid Binding Revisited

    OpenAIRE

    Cai, Jun; Lücke, Christian; Chen, Zhongjing; Qiao, Ye; Klimtchuk, Elena; Hamilton, James A.

    2012-01-01

    Liver fatty acid binding protein (L-FABP), a cytosolic protein most abundant in liver, is associated with intracellular transport of fatty acids, nuclear signaling, and regulation of intracellular lipolysis. Among the members of the intracellular lipid binding protein family, L-FABP is of particular interest as it can i), bind two fatty acid molecules simultaneously and ii), accommodate a variety of bulkier physiological ligands such as bilirubin and fatty acyl CoA. To better understand the p...

  14. Rapid identification of DNA-binding proteins by mass spectrometry

    DEFF Research Database (Denmark)

    Nordhoff, E; Krogsdam, A M; Jorgensen, H F

    1999-01-01

    We report a protocol for the rapid identification of DNA-binding proteins. Immobilized DNA probes harboring a specific sequence motif are incubated with cell or nuclear extract. Proteins are analyzed directly off the solid support by matrix-assisted laser desorption/ionization time-of-flight mass...... was validated by the identification of known prokaryotic and eukaryotic DNA-binding proteins, and its use provided evidence that poly(ADP-ribose) polymerase exhibits DNA sequence-specific binding to DNA....

  15. RNA-Binding Proteins in Trichomonas vaginalis: Atypical Multifunctional Proteins

    Directory of Open Access Journals (Sweden)

    Elisa E. Figueroa-Angulo

    2015-11-01

    Full Text Available Iron homeostasis is highly regulated in vertebrates through a regulatory system mediated by RNA-protein interactions between the iron regulatory proteins (IRPs that interact with an iron responsive element (IRE located in certain mRNAs, dubbed the IRE-IRP regulatory system. Trichomonas vaginalis, the causal agent of trichomoniasis, presents high iron dependency to regulate its growth, metabolism, and virulence properties. Although T. vaginalis lacks IRPs or proteins with aconitase activity, possesses gene expression mechanisms of iron regulation at the transcriptional and posttranscriptional levels. However, only one gene with iron regulation at the transcriptional level has been described. Recently, our research group described an iron posttranscriptional regulatory mechanism in the T. vaginalis tvcp4 and tvcp12 cysteine proteinase mRNAs. The tvcp4 and tvcp12 mRNAs have a stem-loop structure in the 5'-coding region or in the 3'-UTR, respectively that interacts with T. vaginalis multifunctional proteins HSP70, α-Actinin, and Actin under iron starvation condition, causing translation inhibition or mRNA stabilization similar to the previously characterized IRE-IRP system in eukaryotes. Herein, we summarize recent progress and shed some light on atypical RNA-binding proteins that may participate in the iron posttranscriptional regulation in T. vaginalis.

  16. RNA-Binding Proteins in Trichomonas vaginalis: Atypical Multifunctional Proteins.

    Science.gov (United States)

    Figueroa-Angulo, Elisa E; Calla-Choque, Jaeson S; Mancilla-Olea, Maria Inocente; Arroyo, Rossana

    2015-11-26

    Iron homeostasis is highly regulated in vertebrates through a regulatory system mediated by RNA-protein interactions between the iron regulatory proteins (IRPs) that interact with an iron responsive element (IRE) located in certain mRNAs, dubbed the IRE-IRP regulatory system. Trichomonas vaginalis, the causal agent of trichomoniasis, presents high iron dependency to regulate its growth, metabolism, and virulence properties. Although T. vaginalis lacks IRPs or proteins with aconitase activity, possesses gene expression mechanisms of iron regulation at the transcriptional and posttranscriptional levels. However, only one gene with iron regulation at the transcriptional level has been described. Recently, our research group described an iron posttranscriptional regulatory mechanism in the T. vaginalis tvcp4 and tvcp12 cysteine proteinase mRNAs. The tvcp4 and tvcp12 mRNAs have a stem-loop structure in the 5'-coding region or in the 3'-UTR, respectively that interacts with T. vaginalis multifunctional proteins HSP70, α-Actinin, and Actin under iron starvation condition, causing translation inhibition or mRNA stabilization similar to the previously characterized IRE-IRP system in eukaryotes. Herein, we summarize recent progress and shed some light on atypical RNA-binding proteins that may participate in the iron posttranscriptional regulation in T. vaginalis.

  17. Protein binding prodrugs : Synthesis and protein binding studies of didanonsine derivates

    OpenAIRE

    Olberg, Dag Erlend

    2004-01-01

    A novel series of 5 -O-ester prodrugs of the anti-HIV drug 2 ,3 -dideoxyinosine (ddI,didanosine) were synthesized for the purpose of increasing protein binding. Hope was that these derivates would exhibit superior pharmacodynamic and pharmacokinetic properties against HIV-infection than the parent drug, didanosine. Ten compounds were synthesized, five fatty acid derivates and five dicarboxylic acid monoester derivates. The fatty acid- and dicarboxylic acid derivates had the sam...

  18. Bacterial periplasmic sialic acid-binding proteins exhibit a conserved binding site

    Energy Technology Data Exchange (ETDEWEB)

    Gangi Setty, Thanuja [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India); Cho, Christine [Carver College of Medicine, University of Iowa, Iowa City, IA 52242-1109 (United States); Govindappa, Sowmya [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India); Apicella, Michael A. [Carver College of Medicine, University of Iowa, Iowa City, IA 52242-1109 (United States); Ramaswamy, S., E-mail: ramas@instem.res.in [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India)

    2014-07-01

    Structure–function studies of sialic acid-binding proteins from F. nucleatum, P. multocida, V. cholerae and H. influenzae reveal a conserved network of hydrogen bonds involved in conformational change on ligand binding. Sialic acids are a family of related nine-carbon sugar acids that play important roles in both eukaryotes and prokaryotes. These sialic acids are incorporated/decorated onto lipooligosaccharides as terminal sugars in multiple bacteria to evade the host immune system. Many pathogenic bacteria scavenge sialic acids from their host and use them for molecular mimicry. The first step of this process is the transport of sialic acid to the cytoplasm, which often takes place using a tripartite ATP-independent transport system consisting of a periplasmic binding protein and a membrane transporter. In this paper, the structural characterization of periplasmic binding proteins from the pathogenic bacteria Fusobacterium nucleatum, Pasteurella multocida and Vibrio cholerae and their thermodynamic characterization are reported. The binding affinities of several mutations in the Neu5Ac binding site of the Haemophilus influenzae protein are also reported. The structure and the thermodynamics of the binding of sugars suggest that all of these proteins have a very well conserved binding pocket and similar binding affinities. A significant conformational change occurs when these proteins bind the sugar. While the C1 carboxylate has been identified as the primary binding site, a second conserved hydrogen-bonding network is involved in the initiation and stabilization of the conformational states.

  19. Clinical studies of IGFBP-2 by radioimmunoassay

    DEFF Research Database (Denmark)

    Blum, W F; Horn, N; Kratzsch, J

    1993-01-01

    and experimental situations. There was little circadian fluctuations of serum level which showed a marked age-dependence with high levels at birth and senescence and low levels during puberty. Decreased IGFBP-2 levels were present in untreated insulin-dependent diabetes mellitus (IDDM), in acromegaly and during...

  20. Clinical studies of IGFBP-2 by radioimmunoassay

    DEFF Research Database (Denmark)

    Blum, W F; Horn, N; Kratzsch, J;

    1993-01-01

    and experimental situations. There was little circadian fluctuations of serum level which showed a marked age-dependence with high levels at birth and senescence and low levels during puberty. Decreased IGFBP-2 levels were present in untreated insulin-dependent diabetes mellitus (IDDM), in acromegaly and during...

  1. Topological Analyses of Protein-Ligand Binding: a Network Approach.

    Science.gov (United States)

    Costanzi, Stefano

    2016-01-01

    Proteins can be conveniently represented as networks of interacting residues, thus allowing the study of several network parameters that can shed light onto several of their structural and functional aspects. With respect to the binding of ligands, which are central for the function of many proteins, network analysis may constitute a possible route to assist the identification of binding sites. As the bulk of this review illustrates, this has generally been easier for enzymes than for non-enzyme proteins, perhaps due to the different topological nature of the binding sites of the former over those of the latter. The article also illustrates how network representations of binding sites can be used to search PDB structures in order to identify proteins that bind similar molecules and, lastly, how codifying proteins as networks can assist the analysis of the conformational changes consequent to ligand binding.

  2. Discovery of binding proteins for a protein target using protein-protein docking-based virtual screening.

    Science.gov (United States)

    Zhang, Changsheng; Tang, Bo; Wang, Qian; Lai, Luhua

    2014-10-01

    Target structure-based virtual screening, which employs protein-small molecule docking to identify potential ligands, has been widely used in small-molecule drug discovery. In the present study, we used a protein-protein docking program to identify proteins that bind to a specific target protein. In the testing phase, an all-to-all protein-protein docking run on a large dataset was performed. The three-dimensional rigid docking program SDOCK was used to examine protein-protein docking on all protein pairs in the dataset. Both the binding affinity and features of the binding energy landscape were considered in the scoring function in order to distinguish positive binding pairs from negative binding pairs. Thus, the lowest docking score, the average Z-score, and convergency of the low-score solutions were incorporated in the analysis. The hybrid scoring function was optimized in the all-to-all docking test. The docking method and the hybrid scoring function were then used to screen for proteins that bind to tumor necrosis factor-α (TNFα), which is a well-known therapeutic target for rheumatoid arthritis and other autoimmune diseases. A protein library containing 677 proteins was used for the screen. Proteins with scores among the top 20% were further examined. Sixteen proteins from the top-ranking 67 proteins were selected for experimental study. Two of these proteins showed significant binding to TNFα in an in vitro binding study. The results of the present study demonstrate the power and potential application of protein-protein docking for the discovery of novel binding proteins for specific protein targets.

  3. Grape seed extract inhibits advanced human prostate tumor growth and angiogenesis and upregulates insulin-like growth factor binding protein-3.

    Science.gov (United States)

    Singh, Rana P; Tyagi, Anil K; Dhanalakshmi, Sivanandhan; Agarwal, Rajesh; Agarwal, Chapla

    2004-02-20

    Dietary intake of many fruits and vegetables has been shown to be associated with reduced risk of cancer. We investigated the in vivo efficacy of grape seed extract (GSE, patented as Traconol) against prostate cancer (PCA) and associated molecular events. Athymic nude mice were implanted with hormone-refractory human prostate carcinoma DU145 cells and fed with 100 and 200 mg/kg/day (5 days/week) doses of GSE for 7 weeks. At the end of experiment, tumors were immunohistochemically analyzed for cell proliferation, apoptosis and angiogenesis. Our data show that GSE feeding strongly inhibited tumor growth that accounted for 59-73% (p < 0.001) inhibition in tumor volume and 37-47% (p < 0.05) decrease in tumor weight at the end of the experiment. It did not show any significant change in body weight gain profile and diet consumption. Immunohistochemical analysis of tumors showed that GSE decreases proliferation index by 51-66% (p < 0.001) and increases apoptotic index by 3-4-fold (p < 0.001). CD31 staining for endothelial cells, showed decrease in intratumoral microvasculature in GSE-fed group of mice. Control tumors showed 64.0 +/- 1.6 CD31 positive cells/400x field compared to 23.2 +/- 0.9 and 15.7 +/- 0.08 (p < 0.001) CD31 positive cells in 100 and 200 mg/kg doses of GSE-treated tumors, respectively. GSE strongly inhibited (47-70%, p < 0.05) vascular endothelial growth factor (VEGF) secretion in conditioned medium by DU145 cells. Recently, the circulating level of insulin-like growth factor binding protein (IGFBP)-3 is shown to inversely related with PCA risk, growth and prognosis. Consistent with this, we observed 6-7-fold (p < 0.001) increase in tumor-secreted levels of IGFBP-3 after GSE feeding. In other immunohistochemical studies, compared to controls, tumor xenografts from GSE-fed groups of mice showed a moderate decrease in VEGF but an increase in IGFBP-3 levels. These findings suggest that GSE possesses in vivo anticancer efficacy against hormone

  4. Genetic variants in insulin-like growth factor binding protein-3 are associated with prostate cancer susceptibility in Eastern Chinese Han men

    Directory of Open Access Journals (Sweden)

    Zhang G

    2015-12-01

    Full Text Available Guiming Zhang,1–3 Yao Zhu,1,2 Fang Liu,4,5 Chengyuan Gu,1,2 Haitao Chen,4,5 Jianfeng Xu,4–6 Dingwei Ye1,2 1Department of Urology, Fudan University Shanghai Cancer Center, 2Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 3Department of Urology, The Affiliated Hospital of Qingdao University, Shandong, 4Fudan Institute of Urology, Huashan Hospital, Fudan University, 5State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, People’s Republic of China; 6Center for Cancer Genomics, Wake Forest School of Medicine, Winston-Salem, NC, USA Background: Growing evidence has indicated that insulin-like growth factor binding protein-3 (IGFBP-3 polymorphisms are associated with altered risk of prostate cancer (PCa. However, few studies have been conducted in Chinese population to validate this association. Materials and methods: Herein, we examined the association between genetic variants in the IGFBP-3 gene and PCa risk in the Chinese Han population based on a genome-wide association study (1,417 cases and 1,008 controls, and replicated three genetic variants loci in an independent case-control study (1,755 cases and 1,523 controls using Sequenom platform. Logistic regression analyses were performed to estimate odds ratios (ORs and 95% confidence intervals (95% CIs. Results: We found that in the discovery stage, rs9691259 (OR =0.691, 95% CI: 0.587–0.814, P<0.001 and rs6950179 (OR =1.420, 95% CI: 1.201–1.677, P<0.001 were significantly associated with PCa risk, whereas rs2854744 showed a marginal association with PCa risk. In the replication stage, the association between rs9691259 and rs6950179 and PCa risk was not replicated, whereas rs2854744 conferred a significant association with PCa risk (OR =1.399, 95% CI: 1.010–1.937, P=0.043. After combining the two stages, we found that rs9691259, rs6950179, and rs2854744 were all significantly associated with PCa risk. Conclusion

  5. Exploring NMR ensembles of calcium binding proteins: Perspectives to design inhibitors of protein-protein interactions

    Directory of Open Access Journals (Sweden)

    Craescu Constantin T

    2011-05-01

    Full Text Available Abstract Background Disrupting protein-protein interactions by small organic molecules is nowadays a promising strategy employed to block protein targets involved in different pathologies. However, structural changes occurring at the binding interfaces make difficult drug discovery processes using structure-based drug design/virtual screening approaches. Here we focused on two homologous calcium binding proteins, calmodulin and human centrin 2, involved in different cellular functions via protein-protein interactions, and known to undergo important conformational changes upon ligand binding. Results In order to find suitable protein conformations of calmodulin and centrin for further structure-based drug design/virtual screening, we performed in silico structural/energetic analysis and molecular docking of terphenyl (a mimicking alpha-helical molecule known to inhibit protein-protein interactions of calmodulin into X-ray and NMR ensembles of calmodulin and centrin. We employed several scoring methods in order to find the best protein conformations. Our results show that docking on NMR structures of calmodulin and centrin can be very helpful to take into account conformational changes occurring at protein-protein interfaces. Conclusions NMR structures of protein-protein complexes nowadays available could efficiently be exploited for further structure-based drug design/virtual screening processes employed to design small molecule inhibitors of protein-protein interactions.

  6. Biotin-binding proteins and biotin transport to oocytes.

    Science.gov (United States)

    White, H B

    1985-01-01

    The eggs of chickens and other birds contain two proteins that bind biotin. Both are homotetrameric proteins of similar size. In contrast to the well-characterized egg white avidin, egg yolk biotin-binding protein has a very acidic isoelectric point, binds biotin with lower affinity, and is usually saturated with biotin. Like other egg yolk proteins, biotin-binding protein appears to be synthesized in the liver, transported by the blood stream to the ovary and deposited in the developing oocyte. Since the yolk of a chicken egg contains over 90% of the biotin in an egg and all of the biotin is bound to biotin-binding protein, the function of biotin-binding protein is undoubtedly to transport biotin to the egg for future use by the developing embryo. Avidin is produced by the oviduct and in the egg it is presumed to deter microbial growth around the oocyte by sequestering biotin. Among the eggs examined, those from turkeys have the lowest amount of biotin-binding protein and the highest amount of avidin. Furthermore, the majority of the biotin in turkey eggs can be bound to avidin in the egg white, suggesting a nutritional role for avidin in turkeys. An assay has been developed to conveniently measure apo- and holobiotin-binding proteins.

  7. Thermodynamics of ligand binding to acyl-coenzyme A binding protein studied by titration calorimetry

    DEFF Research Database (Denmark)

    Færgeman, Nils J.; Sigurskjold, B W; Kragelund, B B

    1996-01-01

    Ligand binding to recombinant bovine acyl-CoA binding protein (ACBP) was examined using isothermal microcalorimetry. Microcalorimetric measurements confirm that the binding affinity of acyl-CoA esters for ACBP is strongly dependent on the length of the acyl chain with a clear preference for acyl-...

  8. The Plasminogen-Binding Group A Streptococcal M Protein-Related Protein Prp Binds Plasminogen via Arginine and Histidine Residues▿

    Science.gov (United States)

    Sanderson-Smith, Martina L.; Dowton, Mark; Ranson, Marie; Walker, Mark J.

    2007-01-01

    The migration of the human pathogen Streptococcus pyogenes (group A streptococcus) from localized to deep tissue sites may result in severe invasive disease, and sequestration of the host zymogen plasminogen appears crucial for virulence. Here, we describe a novel plasminogen-binding M protein, the plasminogen-binding group A streptococcal M protein (PAM)-related protein (Prp). Prp is phylogenetically distinct from previously described plasminogen-binding M proteins of group A, C, and G streptococci. While competition experiments indicate that Prp binds plasminogen with a lower affinity than PAM (50% effective concentration = 0.34 μM), Prp nonetheless binds plasminogen with high affinity and at physiologically relevant concentrations of plasminogen (Kd = 7.8 nM). Site-directed mutagenesis of the putative plasminogen binding site indicates that unlike the majority of plasminogen receptors, Prp does not interact with plasminogen exclusively via lysine residues. Mutagenesis to alanine of lysine residues Lys96 and Lys101 reduced but did not abrogate plasminogen binding by Prp. Plasminogen binding was abolished only with the additional mutagenesis of Arg107 and His108 to alanine. Furthermore, mutagenesis of Arg107 and His108 abolished plasminogen binding by Prp despite the presence of Lys96 and Lys101 in the binding site. Thus, binding to plasminogen via arginine and histidine residues appears to be a conserved mechanism among plasminogen-binding M proteins. PMID:17012384

  9. The plasminogen-binding group A streptococcal M protein-related protein Prp binds plasminogen via arginine and histidine residues.

    Science.gov (United States)

    Sanderson-Smith, Martina L; Dowton, Mark; Ranson, Marie; Walker, Mark J

    2007-02-01

    The migration of the human pathogen Streptococcus pyogenes (group A streptococcus) from localized to deep tissue sites may result in severe invasive disease, and sequestration of the host zymogen plasminogen appears crucial for virulence. Here, we describe a novel plasminogen-binding M protein, the plasminogen-binding group A streptococcal M protein (PAM)-related protein (Prp). Prp is phylogenetically distinct from previously described plasminogen-binding M proteins of group A, C, and G streptococci. While competition experiments indicate that Prp binds plasminogen with a lower affinity than PAM (50% effective concentration = 0.34 microM), Prp nonetheless binds plasminogen with high affinity and at physiologically relevant concentrations of plasminogen (K(d) = 7.8 nM). Site-directed mutagenesis of the putative plasminogen binding site indicates that unlike the majority of plasminogen receptors, Prp does not interact with plasminogen exclusively via lysine residues. Mutagenesis to alanine of lysine residues Lys(96) and Lys(101) reduced but did not abrogate plasminogen binding by Prp. Plasminogen binding was abolished only with the additional mutagenesis of Arg(107) and His(108) to alanine. Furthermore, mutagenesis of Arg(107) and His(108) abolished plasminogen binding by Prp despite the presence of Lys(96) and Lys(101) in the binding site. Thus, binding to plasminogen via arginine and histidine residues appears to be a conserved mechanism among plasminogen-binding M proteins.

  10. Free and total insulin-like growth factor I (IGF-I), IGF-binding protein-1 (IGFBP-1), and IGFBP-3 and their relationships to the presence of diabetic retinopathy and glomerular hyperfiltration in insulin-dependent diabetes mellitus

    NARCIS (Netherlands)

    J.A.M.J.L. Janssen (Joseph); M.L. Jacobs (Marloes); F.H.M. Derkx (Frans); R.F.A. Weber (Robert); A-J. van der Lely (Aart-Jan); S.W.J. Lamberts (Steven)

    1997-01-01

    textabstractThe existing literature on serum insulin-like growth factor I (IGF-I) levels in insulin-dependent diabetes mellitus (IDDM) is conflicting. Free IGF-I may have greater physiological and clinical relevance than total IGF-I. Recently, a validated method has

  11. SONAR Discovers RNA-Binding Proteins from Analysis of Large-Scale Protein-Protein Interactomes.

    Science.gov (United States)

    Brannan, Kristopher W; Jin, Wenhao; Huelga, Stephanie C; Banks, Charles A S; Gilmore, Joshua M; Florens, Laurence; Washburn, Michael P; Van Nostrand, Eric L; Pratt, Gabriel A; Schwinn, Marie K; Daniels, Danette L; Yeo, Gene W

    2016-10-20

    RNA metabolism is controlled by an expanding, yet incomplete, catalog of RNA-binding proteins (RBPs), many of which lack characterized RNA binding domains. Approaches to expand the RBP repertoire to discover non-canonical RBPs are currently needed. Here, HaloTag fusion pull down of 12 nuclear and cytoplasmic RBPs followed by quantitative mass spectrometry (MS) demonstrates that proteins interacting with multiple RBPs in an RNA-dependent manner are enriched for RBPs. This motivated SONAR, a computational approach that predicts RNA binding activity by analyzing large-scale affinity precipitation-MS protein-protein interactomes. Without relying on sequence or structure information, SONAR identifies 1,923 human, 489 fly, and 745 yeast RBPs, including over 100 human candidate RBPs that contain zinc finger domains. Enhanced CLIP confirms RNA binding activity and identifies transcriptome-wide RNA binding sites for SONAR-predicted RBPs, revealing unexpected RNA binding activity for disease-relevant proteins and DNA binding proteins.

  12. A β-hairpin-binding protein for three different disease-related amyloidogenic proteins.

    Science.gov (United States)

    Shaykhalishahi, Hamed; Mirecka, Ewa A; Gauhar, Aziz; Grüning, Clara S R; Willbold, Dieter; Härd, Torleif; Stoldt, Matthias; Hoyer, Wolfgang

    2015-02-01

    Amyloidogenic proteins share a propensity to convert to the β-structure-rich amyloid state that is associated with the progression of several protein-misfolding disorders. Here we show that a single engineered β-hairpin-binding protein, the β-wrapin AS10, binds monomers of three different amyloidogenic proteins, that is, amyloid-β peptide, α-synuclein, and islet amyloid polypeptide, with sub-micromolar affinity. AS10 binding inhibits the aggregation and toxicity of all three proteins. The results demonstrate common conformational preferences and related binding sites in a subset of the amyloidogenic proteins. These commonalities enable the generation of multispecific monomer-binding agents.

  13. SCOWLP classification: Structural comparison and analysis of protein binding regions

    Directory of Open Access Journals (Sweden)

    Anders Gerd

    2008-01-01

    Full Text Available Abstract Background Detailed information about protein interactions is critical for our understanding of the principles governing protein recognition mechanisms. The structures of many proteins have been experimentally determined in complex with different ligands bound either in the same or different binding regions. Thus, the structural interactome requires the development of tools to classify protein binding regions. A proper classification may provide a general view of the regions that a protein uses to bind others and also facilitate a detailed comparative analysis of the interacting information for specific protein binding regions at atomic level. Such classification might be of potential use for deciphering protein interaction networks, understanding protein function, rational engineering and design. Description Protein binding regions (PBRs might be ideally described as well-defined separated regions that share no interacting residues one another. However, PBRs are often irregular, discontinuous and can share a wide range of interacting residues among them. The criteria to define an individual binding region can be often arbitrary and may differ from other binding regions within a protein family. Therefore, the rational behind protein interface classification should aim to fulfil the requirements of the analysis to be performed. We extract detailed interaction information of protein domains, peptides and interfacial solvent from the SCOWLP database and we classify the PBRs of each domain family. For this purpose, we define a similarity index based on the overlapping of interacting residues mapped in pair-wise structural alignments. We perform our classification with agglomerative hierarchical clustering using the complete-linkage method. Our classification is calculated at different similarity cut-offs to allow flexibility in the analysis of PBRs, feature especially interesting for those protein families with conflictive binding regions

  14. Quantitative analysis of pheromone-binding protein specificity

    OpenAIRE

    Katti, S.; Lokhande, N.; D González; Cassill, A.; Renthal, R

    2012-01-01

    Many pheromones have very low water solubility, posing experimental difficulties for quantitative binding measurements. A new method is presented for determining thermodynamically valid dissociation constants for ligands binding to pheromone-binding proteins (OBPs), using β-cyclodextrin as a solubilizer and transfer agent. The method is applied to LUSH, a Drosophila OBP that binds the pheromone 11-cis vaccenyl acetate (cVA). Refolding of LUSH expressed in E. coli was assessed by measuring N-p...

  15. Insulin-like growth factor I (IGF-I) replacement during growth hormone receptor antagonism normalizes serum IGF-binding protein-3 and markers of bone formation in ovariectomized rhesus monkeys.

    Science.gov (United States)

    Wilson, M E

    2000-04-01

    Previous work from this laboratory has shown that the constant sc infusion of insulin-like growth factor I (IGF-I) to normal pituitary monkeys results in a sustained elevation in circulating concentrations of IGF-binding protein-3 (IGFBP-3), whereas the acute administration of IGF-I to monkeys pretreated with a GH receptor antagonist produces a brief, but significant, elevation in serum IGFBP-3. The present study tested the hypothesis that the constant infusion of IGF-I would normalize serum concentrations of IGFBP-3 in females treated with the GH receptor antagonist. To assess the biological significance of these effects, serum levels of the acid-labile subunit (ALS) and biomarkers for bone formation, osteocalcin, and collagen type I C-terminal propeptide, were also examined. Five female rhesus monkeys were studied over 21 consecutive days involving 7 days of baseline, 7 days of treatment with the GH receptor antagonist (1.0 mg/kg-week, sc), and 7 days of treatment with the GH receptor antagonist supplemented with IGF-I (120 microg/kg x day, sc infusion with osmotic minipump). Within 48 h of the initiation of treatment with the GH receptor antagonist, serum IGF-I and IGFBP-3 were decreased by 40% and 18% from baseline, respectively, and levels continued to decline through the remainder of treatment. However, within 48 h of the initiation of IGF-I administration during GH receptor antagonist treatment, both serum IGF-I and IGFBP-3 were elevated and normalized to baseline values. Serum concentrations of ALS were also decreased by GH antagonism, but levels increased in some (n = 2), but not all, subjects upon administration of IGF-I. Size exclusion ultrafiltration indicated that the amount of IGF-I found in the high molecular mass complex (>100 kDa) decreased significantly during GH antagonism, but was similar during the baseline and IGF-I infusion phases. Finally, treatment with the GH receptor antagonist also significantly reduced serum levels of osteocalcin and

  16. Characterization of the DNA binding properties of polyomavirus capsid protein

    Science.gov (United States)

    Chang, D.; Cai, X.; Consigli, R. A.; Spooner, B. S. (Principal Investigator)

    1993-01-01

    The DNA binding properties of the polyomavirus structural proteins VP1, VP2, and VP3 were studied by Southwestern analysis. The major viral structural protein VP1 and host-contributed histone proteins of polyomavirus virions were shown to exhibit DNA binding activity, but the minor capsid proteins VP2 and VP3 failed to bind DNA. The N-terminal first five amino acids (Ala-1 to Lys-5) were identified as the VP1 DNA binding domain by genetic and biochemical approaches. Wild-type VP1 expressed in Escherichia coli (RK1448) exhibited DNA binding activity, but the N-terminal truncated VP1 mutants (lacking Ala-1 to Lys-5 and Ala-1 to Cys-11) failed to bind DNA. The synthetic peptide (Ala-1 to Cys-11) was also shown to have an affinity for DNA binding. Site-directed mutagenesis of the VP1 gene showed that the point mutations at Pro-2, Lys-3, and Arg-4 on the VP1 molecule did not affect DNA binding properties but that the point mutation at Lys-5 drastically reduced DNA binding affinity. The N-terminal (Ala-1 to Lys-5) region of VP1 was found to be essential and specific for DNA binding, while the DNA appears to be non-sequence specific. The DNA binding domain and the nuclear localization signal are located in the same N-terminal region.

  17. Total and free insulin-like growth factor I, insulin-like growth factor binding protein 3 and acid-labile subunit reflect clinical activity in acromegaly

    DEFF Research Database (Denmark)

    Sneppen, S B; Lange, Merete Wolder; Pedersen, L M

    2001-01-01

    the inactive and the active groups, we found that positive and negative predictive values (PV(pos), PV(neg)) for clinical disease activity of total and free insulin-like growth factor-I (IGF-I) were 0.59, 0.90 and 1.00, 0.82 respectively. Acid-labile subunit (ALS) showed diagnostic merit similar to insulin......-like growth factor binding protein-3 (IGFBP-3) with PV(pos) of 0.69 and 0.71 and PV(neg) of 0.91 and 0.92 respectively. We conclude that free IGF-I is more closely related than total IGF-I to perceived disease activity and is as such useful when evaluating previously treated acromegaly for disease activity...

  18. Calcium-binding proteins from human platelets

    Energy Technology Data Exchange (ETDEWEB)

    Gogstad, G.O.; Krutnes, M.B.; Solum, N.O.

    1983-06-01

    Calcium-binding platelet proteins were examined by crossed immunoelectrophoresis of solubilized platelets against antibodies to whole platelets followed by incubation of the immunoplates with /sup 45/Ca/sup 2 +/ and autoradiography. When the immunoplates had been pretreated with EDTA at pH 9.0 in order to remove divalent cations, three immunoprecipitates were markedly labelled with /sup 45/Ca/sup 2 +/. These corresponded to the glycoprotein IIb-IIIa complex, glycoprotein Ia and a presently unidentified antigen termed G18. These antigens were membrane-bound and surface-oriented. When an excess of EDTA was introduced in the incubation media the results revealed that the glycoprotein IIb-IIIa complex and antigen G18, but not glycoprotein Ia, contained sites with a stronger affinity for calcium than has EDTA at pH 7.4. Immunoprecipitates of the separate glycoproteins IIb and IIIa both bound calcium in the same manner as the glycoprotein IIb-IIIa complex. As another approach, platelet-rich plasma was incubated with /sup 45/Ca/sup 2 +/ prior to crossed immunoelectrophoresis of the solubilized platelets. A single immunoprecipitate was weakly labelled. This did not correspond to any of the immunoprecipitates which were visible after staining with Coomassie blue. The labelling of this antigen was markedly increased when the platelet-rich plasma had been preincubated with EDTA and in this case a weak labelling of the glycoprotein IIB-IIIa precipitate also became apparent. No increased incorporation of calcium occured in any of these immunoprecipitates when the platelets were aggregated with ADP in the presence of /sup 45/Ca/sup 2 +/.

  19. Global discovery of protein kinases and other nucleotide-binding proteins by mass spectrometry.

    Science.gov (United States)

    Xiao, Yongsheng; Wang, Yinsheng

    2016-09-01

    Nucleotide-binding proteins, such as protein kinases, ATPases and GTP-binding proteins, are among the most important families of proteins that are involved in a number of pivotal cellular processes. However, global study of the structure, function, and expression level of nucleotide-binding proteins as well as protein-nucleotide interactions can hardly be achieved with the use of conventional approaches owing to enormous diversity of the nucleotide-binding protein family. Recent advances in mass spectrometry (MS) instrumentation, coupled with a variety of nucleotide-binding protein enrichment methods, rendered MS-based proteomics a powerful tool for the comprehensive characterizations of the nucleotide-binding proteome, especially the kinome. Here, we review the recent developments in the use of mass spectrometry, together with general and widely used affinity enrichment approaches, for the proteome-wide capture, identification and quantification of nucleotide-binding proteins, including protein kinases, ATPases, GTPases, and other nucleotide-binding proteins. The working principles, advantages, and limitations of each enrichment platform in identifying nucleotide-binding proteins as well as profiling protein-nucleotide interactions are summarized. The perspectives in developing novel MS-based nucleotide-binding protein detection platform are also discussed. © 2014 Wiley Periodicals, Inc. Mass Spec Rev 35:601-619, 2016.

  20. Affinity purification of sequence-specific DNA binding proteins.

    OpenAIRE

    1986-01-01

    We describe a method for affinity purification of sequence-specific DNA binding proteins that is fast and effective. Complementary chemically synthesized oligodeoxynucleotides that contain a recognition site for a sequence-specific DNA binding protein are annealed and ligated to give oligomers. This DNA is then covalently coupled to Sepharose CL-2B with cyanogen bromide to yield the affinity resin. A partially purified protein fraction is combined with competitor DNA and subsequently passed t...

  1. The Cobalamin-binding Protein in Zebrafish is an Intermediate Between the Three Cobalamin-binding Proteins in Human

    DEFF Research Database (Denmark)

    Greibe, Eva Holm; Fedosov, Sergey; Nexø, Ebba

    2012-01-01

    knowledge concerning the phylogenetic evolution of kindred proteins. We identified a cobalamin binding capacity in zebrafish protein extracts (8.2 pmol/fish) and ambient water (13.5 pmol/fish) associated with a single protein. The protein showed resistance toward degradation by trypsin and chymotrypsin...

  2. Growth hormone (GH) secretory dynamics in a case of acromegalic gigantism associated with hyperprolactinemia: nonpulsatile secretion of GH may induce elevated insulin-like growth factor-I (IGF-I) and IGF-binding protein-3 levels.

    Science.gov (United States)

    Yoshida, T; Shimatsu, A; Sakane, N; Hizuka, N; Horikawa, R; Tanaka, T

    1996-01-01

    We describe a case of pituitary gigantism with low levels of growth hormone (GH), elevated insulin-like growth factor-I (IGF-I), and IGF-binding protein-3 (IGF-BP-3). The patient had characteristic clinical features of gigantism and acromegaly. The basal serum GH levels ranged from 1.2-1.9 micrograms/L, which were considered to be within normal limits. Serum GH response to either insulin-induced hypoglycemia or GH-releasing hormone was blunted. Frequent blood samplings during daytime and at night showed nonpulsatile GH secretion. Serum prolactin, IGF-I and IGF-binding protein-3 levels were elevated. After unsuccessful surgery, bromocryptine treatment normalized serum prolactin without affecting serum GH and IGF-I levels. Combined administration of octreotide and bromocryptine reduced serum GH and IGF-I levels. GH bioactivity as measured by Nb2 cell proliferation assay was within reference range. In the present case, nonpulsatile GH secretion and enhanced tissue sensitivity to GH may induce hypersecretion of IGF-I and IGF-BP-3 and cause clinical acromegalic gigantism.

  3. Stereoselective binding of chiral drugs to plasma proteins

    Institute of Scientific and Technical Information of China (English)

    Qi SHEN; Lu WANG; Hui ZHOU; Hui-di JIANG; Lu-shan YU; Su ZENG

    2013-01-01

    Chiral drugs show distinct biochemical and pharmacological behaviors in the human body.The binding of chiral drugs to plasma proteins usually exhibits stereoselectivity,which has a far-reaching influence on their pharmacological activities and pharmacokinetic profiles.In this review,the stereoselective binding of chiral drugs to human serum albumin (HSA),α1-acid glycoprotein (AGP)and lipoprotein,three most important proteins in human plasma,are detailed.Furthermore,the application of AGP variants and recombinant fragments of HSA for studying enantiomer binding properties is also discussed.Apart from the stereoselectivity of enantiomer-protein binding,enantiomer-enantiomer interactions that may induce allosteric effects are also described.Additionally,the techniques and methods used to determine drug-protein binding parameters are briefly reviewed.

  4. CaMELS: In silico prediction of calmodulin binding proteins and their binding sites.

    Science.gov (United States)

    Abbasi, Wajid Arshad; Asif, Amina; Andleeb, Saiqa; Minhas, Fayyaz Ul Amir Afsar

    2017-09-01

    Due to Ca(2+) -dependent binding and the sequence diversity of Calmodulin (CaM) binding proteins, identifying CaM interactions and binding sites in the wet-lab is tedious and costly. Therefore, computational methods for this purpose are crucial to the design of such wet-lab experiments. We present an algorithm suite called CaMELS (CalModulin intEraction Learning System) for predicting proteins that interact with CaM as well as their binding sites using sequence information alone. CaMELS offers state of the art accuracy for both CaM interaction and binding site prediction and can aid biologists in studying CaM binding proteins. For CaM interaction prediction, CaMELS uses protein sequence features coupled with a large-margin classifier. CaMELS models the binding site prediction problem using multiple instance machine learning with a custom optimization algorithm which allows more effective learning over imprecisely annotated CaM-binding sites during training. CaMELS has been extensively benchmarked using a variety of data sets, mutagenic studies, proteome-wide Gene Ontology enrichment analyses and protein structures. Our experiments indicate that CaMELS outperforms simple motif-based search and other existing methods for interaction and binding site prediction. We have also found that the whole sequence of a protein, rather than just its binding site, is important for predicting its interaction with CaM. Using the machine learning model in CaMELS, we have identified important features of protein sequences for CaM interaction prediction as well as characteristic amino acid sub-sequences and their relative position for identifying CaM binding sites. Python code for training and evaluating CaMELS together with a webserver implementation is available at the URL: http://faculty.pieas.edu.pk/fayyaz/software.html#camels. © 2017 Wiley Periodicals, Inc.

  5. Lipids and lipid binding proteins: a perfect match.

    Science.gov (United States)

    Glatz, Jan F C

    2015-02-01

    Lipids serve a great variety of functions, ranging from structural components of biological membranes to signaling molecules affecting various cellular functions. Several of these functions are related to the unique physico-chemical properties shared by all lipid species, i.e., their hydrophobicity. The latter, however, is accompanied by a poor solubility in an aqueous environment and thus a severe limitation in the transport of lipids in aqueous compartments such as blood plasma and the cellular soluble cytoplasm. Specific proteins which can reversibly and non-covalently associate with lipids, designated as lipid binding proteins or lipid chaperones, greatly enhance the aqueous solubility of lipids and facilitate their transport between tissues and within tissue cells. Importantly, transport of lipids across biological membranes also is facilitated by specific (membrane-associated) lipid binding proteins. Together, these lipid binding proteins determine the bio-availability of their ligands, and thereby markedly influence the subsequent processing, utilization, or signaling effect of lipids. The bio-availability of specific lipid species thus is governed by the presence of specific lipid binding proteins, the affinity of these proteins for distinct lipid species, and the presence of competing ligands (including pharmaceutical compounds). Recent studies suggest that post-translational modifications of lipid binding proteins may have great impact on lipid-protein interactions. As a result, several levels of regulation exist that together determine the bio-availability of lipid species. This short review discusses the significance of lipid binding proteins and their potential application as targets for therapeutic intervention.

  6. Further biochemical characterization of Mycobacterium leprae laminin-binding proteins

    Directory of Open Access Journals (Sweden)

    M.A.M. Marques

    2001-04-01

    Full Text Available It has been demonstrated that the alpha2 chain of laminin-2 present on the surface of Schwann cells is involved in the process of attachment of Mycobacterium leprae to these cells. Searching for M. leprae laminin-binding molecules, in a previous study we isolated and characterized the cationic proteins histone-like protein (Hlp and ribosomal proteins S4 and S5 as potential adhesins involved in M. leprae-Schwann cell interaction. Hlp was shown to bind alpha2-laminins and to greatly enhance the attachment of mycobacteria to ST88-14 Schwann cells. In the present study, we investigated the laminin-binding capacity of the ribosomal proteins S4 and S5. The genes coding for these proteins were PCR amplified and their recombinant products were shown to bind alpha2-laminins in overlay assays. However, when tested in ELISA-based assays and in adhesion assays with ST88-14 cells, in contrast to Hlp, S4 and S5 failed to bind laminin and act as adhesins. The laminin-binding property and adhesin capacity of two basic host-derived proteins were also tested, and only histones, but not cytochrome c, were able to increase bacterial attachment to ST88-14 cells. Our data suggest that the alanine/lysine-rich sequences shared by Hlp and eukaryotic H1 histones might be involved in the binding of these cationic proteins to laminin.

  7. Identification of IgE-binding proteins in soy lecithin.

    Science.gov (United States)

    Gu, X; Beardslee, T; Zeece, M; Sarath, G; Markwell, J

    2001-11-01

    Soy lecithin is widely used as an emulsifier in processed foods, pharmaceuticals and cosmetics. Soy lecithin is composed principally of phospholipids; however, it has also been shown to contain IgE-binding proteins, albeit at a low level. A few clinical cases involving allergic reactions to soy lecithin have been reported. The purpose of this investigation is to better characterize the IgE-binding proteins typically found in lecithin. Soy lecithin proteins were isolated following solvent extraction of lipid components and then separated on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The separated lecithin proteins were immunoblotted with sera from soy-sensitive individuals to determine the pattern of IgE-binding proteins. The identity of IgE-reactive bands was determined from their N-terminal sequence. The level of protein in six lecithin samples obtained from commercial suppliers ranged from 100 to 1,400 ppm. Lecithin samples showed similar protein patterns when examined by SDS-PAGE. Immunoblotting with sera from soy-sensitive individuals showed IgE binding to bands corresponding to 7, 12, 20, 39 and 57 kD. N-terminal analysis of these IgE-binding bands resulted in sequences for 3 components. The 12-kD band was identified as a methionine-rich protein (MRP) and a member of the 2S albumin class of soy proteins. The 20-kD band was found to be soybean Kunitz trypsin inhibitor. The 39-kD band was matched to a soy protein with unknown function. Soy lecithin contains a number of IgE-binding proteins; thus, it might represent a source of hidden allergens. These allergens are a more significant concern for soy-allergic individuals consuming lecithin products as a health supplement. In addition, the MRP and the 39-kD protein identified in this study represent newly identified IgE-binding proteins. Copyright 2001 S. Karger AG, Basel

  8. Comparative serum protein binding of anthracycline derivatives.

    Science.gov (United States)

    Chassany, O; Urien, S; Claudepierre, P; Bastian, G; Tillement, J P

    1996-01-01

    The binding of doxorubicin, iododoxorubicin, daunorubicin, epirubicin, pirarubicin, zorubicin, aclarubicin, and mitoxantrone to 600 microM human serum albumin and 50 microM alpha 1-acid glycoprotein was studied by ultrafiltration at 37 degrees C and pH 7.4. Anthracycline concentrations (total and free) were determined by high-performance liquid chromatography (HPLC) with fluorometric detection. Binding to albumin (600 microM) varied from 61% (daunorubicin) to 94% (iododoxorubicin). The binding to alpha 1-acid glycoprotein (50 microM) was more variable, ranging from 31% (epirubicin) to 64% (zorubicin), and was essentially related to the hydrophobicity of the derivatives. Simulations showed that the total serum binding varied over a broad range from 71% (doxorubicin) to 96% (iododoxorubicin). We recently reported that the binding to lipoproteins of a series of eight anthracycline analogues could be ascribed to chemicophysical determinants of lipophilicity [2]. The present study was conducted to evaluate in vitro the contribution of albumin and alpha 1-acid glycoprotein to the total serum binding of these drugs.

  9. Sequence and structural features of binding site residues in protein-protein complexes: comparison with protein-nucleic acid complexes

    Directory of Open Access Journals (Sweden)

    Selvaraj S

    2011-10-01

    Full Text Available Abstract Background Protein-protein interactions are important for several cellular processes. Understanding the mechanism of protein-protein recognition and predicting the binding sites in protein-protein complexes are long standing goals in molecular and computational biology. Methods We have developed an energy based approach for identifying the binding site residues in protein–protein complexes. The binding site residues have been analyzed with sequence and structure based parameters such as binding propensity, neighboring residues in the vicinity of binding sites, conservation score and conformational switching. Results We observed that the binding propensities of amino acid residues are specific for protein-protein complexes. Further, typical dipeptides and tripeptides showed high preference for binding, which is unique to protein-protein complexes. Most of the binding site residues are highly conserved among homologous sequences. Our analysis showed that 7% of residues changed their conformations upon protein-protein complex formation and it is 9.2% and 6.6% in the binding and non-binding sites, respectively. Specifically, the residues Glu, Lys, Leu and Ser changed their conformation from coil to helix/strand and from helix to coil/strand. Leu, Ser, Thr and Val prefer to change their conformation from strand to coil/helix. Conclusions The results obtained in this study will be helpful for understanding and predicting the binding sites in protein-protein complexes.

  10. Vitamin D. Treatment of Prostate Cancer: The Inhibitory Role of IGFBP-3

    Science.gov (United States)

    2005-01-01

    initiation site of the vitamin D receptor gene is associated with low bone mineral density in postmenopausal Mexican - American women . J Bone Miner Res 11...Systems Laboratories, Inc., Webster, Texas ). However, a combination of calcitriol with androgen resulted in a remarkable increase in IGFBP-3 mRNA of over...regulators including retinoids, rosiglitazone (a diabetes drug that binds to PPARs) and HDAC inhibitor and has evaluated the potency of several calcitriol

  11. Echinococcus granulosus fatty acid binding proteins subcellular localization.

    Science.gov (United States)

    Alvite, Gabriela; Esteves, Adriana

    2016-05-01

    Two fatty acid binding proteins, EgFABP1 and EgFABP2, were isolated from the parasitic platyhelminth Echinococcus granulosus. These proteins bind fatty acids and have particular relevance in flatworms since de novo fatty acids synthesis is absent. Therefore platyhelminthes depend on the capture and intracellular distribution of host's lipids and fatty acid binding proteins could participate in lipid distribution. To elucidate EgFABP's roles, we investigated their intracellular distribution in the larval stage by a proteomic approach. Our results demonstrated the presence of EgFABP1 isoforms in cytosolic, nuclear, mitochondrial and microsomal fractions, suggesting that these molecules could be involved in several cellular processes.

  12. Predicting nucleic acid binding interfaces from structural models of proteins.

    Science.gov (United States)

    Dror, Iris; Shazman, Shula; Mukherjee, Srayanta; Zhang, Yang; Glaser, Fabian; Mandel-Gutfreund, Yael

    2012-02-01

    The function of DNA- and RNA-binding proteins can be inferred from the characterization and accurate prediction of their binding interfaces. However, the main pitfall of various structure-based methods for predicting nucleic acid binding function is that they are all limited to a relatively small number of proteins for which high-resolution three-dimensional structures are available. In this study, we developed a pipeline for extracting functional electrostatic patches from surfaces of protein structural models, obtained using the I-TASSER protein structure predictor. The largest positive patches are extracted from the protein surface using the patchfinder algorithm. We show that functional electrostatic patches extracted from an ensemble of structural models highly overlap the patches extracted from high-resolution structures. Furthermore, by testing our pipeline on a set of 55 known nucleic acid binding proteins for which I-TASSER produces high-quality models, we show that the method accurately identifies the nucleic acids binding interface on structural models of proteins. Employing a combined patch approach we show that patches extracted from an ensemble of models better predicts the real nucleic acid binding interfaces compared with patches extracted from independent models. Overall, these results suggest that combining information from a collection of low-resolution structural models could be a valuable approach for functional annotation. We suggest that our method will be further applicable for predicting other functional surfaces of proteins with unknown structure. Copyright © 2011 Wiley Periodicals, Inc.

  13. Identification of AOSC-binding proteins in neurons

    Institute of Scientific and Technical Information of China (English)

    LIU Ming; NIE Qin; XIN Xianliang; GENG Meiyu

    2008-01-01

    Acidic oligosaccharide sugar chain (AOSC), a D-mannuronic acid oligosaccharide, derived from brown algae polysaccharide, has been completed Phase I clinical trial in China as an anti-Alzheimer's Disease (AD) drug candidate. The identification of AOSC-binding protein(s) in neurons is very important for understanding its action mechanism. To determine the binding protein(s) of AOSC in neurons mediating its anti-AD activities, confocal microscopy, affinity chromatography, and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis were used. Confocal microscopy analysis shows that AOSC binds to SH-SY5Y cells in concentration-, time-, and temperature-dependent fashions. The AOSC binding proteins were purified by affinity chromatography and identified by LC-MS/MS analysis. The results showed that there are 349 proteins binding AOSC, including clathrin, adaptor protein-2 (AP-2) and amyloid precursor protein (APP). These results suggest that the binding/entrance of AOSC to neurons is probably responsible for anti-AD activities.

  14. Analysis of the ligand binding properties of recombinant bovine liver-type fatty acid binding protein

    DEFF Research Database (Denmark)

    Rolf, B; Oudenampsen-Krüger, E; Börchers, T

    1995-01-01

    The coding part of the cDNA for bovine liver-type fatty acid binding protein (L-FABP) has been amplified by RT-PCR, cloned and used for the construction of an Escherichia coli (E. coli) expression system. The recombinant protein made up to 25% of the soluble E. coli proteins and could be isolated...

  15. HTLV-1 Tax Protein Stimulation of DNA Binding of bZIP Proteins by Enhancing Dimerization

    Science.gov (United States)

    Wagner, Susanne; Green, Michael R.

    1993-10-01

    The Tax protein of human T cell leukemia virus type-1 (HTLV-I) transcriptionally activates the HTLV-I promoter. This activation requires binding sites for activating transcription factor (ATF) proteins, a family of cellular proteins that contain basic region-leucine zipper (bZIP) DNA binding domains. Data are presented showing that Tax increases the in vitro DNA binding activity of multiple ATF proteins. Tax also stimulated DNA binding by other bZIP proteins, but did not affect DNA binding proteins that lack a bZIP domain. The increase in DNA binding occurred because Tax promotes dimerization of the bZIP domain in the absence of DNA, and the elevated concentration of the bZIP homodimer then facilitates the DNA binding reaction. These results help explain how Tax activates viral transcription and transforms cells.

  16. Diversity of Cyclic Di-GMP-Binding Proteins and Mechanisms.

    Science.gov (United States)

    Chou, Shan-Ho; Galperin, Michael Y

    2016-01-01

    Cyclic di-GMP (c-di-GMP) synthetases and hydrolases (GGDEF, EAL, and HD-GYP domains) can be readily identified in bacterial genome sequences by using standard bioinformatic tools. In contrast, identification of c-di-GMP receptors remains a difficult task, and the current list of experimentally characterized c-di-GMP-binding proteins is likely incomplete. Several classes of c-di-GMP-binding proteins have been structurally characterized; for some others, the binding sites have been identified; and for several potential c-di-GMP receptors, the binding sites remain to be determined. We present here a comparative structural analysis of c-di-GMP-protein complexes that aims to discern the common themes in the binding mechanisms that allow c-di-GMP receptors to bind it with (sub)micromolar affinities despite the 1,000-fold excess of GTP. The available structures show that most receptors use their Arg and Asp/Glu residues to bind c-di-GMP monomers, dimers, or tetramers with stacked guanine bases. The only exception is the EAL domains that bind c-di-GMP monomers in an extended conformation. We show that in c-di-GMP-binding signature motifs, Arg residues bind to the O-6 and N-7 atoms at the Hoogsteen edge of the guanine base, while Asp/Glu residues bind the N-1 and N-2 atoms at its Watson-Crick edge. In addition, Arg residues participate in stacking interactions with the guanine bases of c-di-GMP and the aromatic rings of Tyr and Phe residues. This may account for the presence of Arg residues in the active sites of every receptor protein that binds stacked c-di-GMP. We also discuss the implications of these structural data for the improved understanding of the c-di-GMP signaling mechanisms.

  17. Notch2 controls prolactin and insulin-like growth factor binding protein-1 expression in decidualizing human stromal cells of early pregnancy.

    Directory of Open Access Journals (Sweden)

    Gerlinde R Otti

    Full Text Available Decidualization, the transformation of the human uterine mucosa into the endometrium of pregnancy, is critical for successful implantation and embryonic development. However, key regulatory factors controlling differentiation of uterine stromal cells into hormone-secreting decidual cells have not been fully elucidated. Hence, we herein investigated the role of the Notch signaling pathway in human decidual stromal cells (HDSC isolated from early pregnancy samples. Immunofluorescence of first trimester decidual tissues revealed expression of Notch2 receptor and its putative, membrane-anchored interaction partners Jagged1, Delta-like (DLL 1 and DLL4 in stromal cells whereas other Notch receptors and ligands were absent from these cells. During in vitro differentiation with estrogen/progesterone (E2P4 and/or cyclic adenosine monophosphate (cAMP HDSC constitutively expressed Notch2 and weakly downregulated Jagged1 mRNA and protein, measured by quantitative PCR (qPCR and Western blotting, respectively. However, increased levels of DLL1 and DLL4 were observed in the decidualizing cultures. Transfection of a Notch luciferase reporter and qPCR of the Notch target gene hairy and enhancer of split 1 (HES1 revealed an induction of canonical Notch activity during in vitro differentiation. In contrast, treatment of HDSC with a chemical Notch/γ-secretase inhibitor decreased cAMP/E2P4-stimulated Notch luciferase activity, HES1 transcript levels and mRNA expression of the decidual marker genes prolactin (PRL and insulin-like growth factor binding protein 1 (IGFBP1. Similarly, siRNA-mediated gene silencing or antibody-mediated blocking of Notch2 diminished HES1, PRL and IGFBP1 mRNA levels as well as secreted PRL protein. In summary, the data suggest that canonical, Notch2-dependent signaling plays a role in human decidualization.

  18. Pleiotropic virulence factor - Streptococcus pyogenes fibronectin-binding proteins.

    Science.gov (United States)

    Yamaguchi, Masaya; Terao, Yutaka; Kawabata, Shigetada

    2013-04-01

    Streptococcus pyogenes causes a broad spectrum of infectious diseases, including pharyngitis, skin infections and invasive necrotizing fasciitis. The initial phase of infection involves colonization, followed by intimate contact with the host cells, thus promoting bacterial uptake by them. S. pyogenes recognizes fibronectin (Fn) through its own Fn-binding proteins to obtain access to epithelial and endothelial cells in host tissue. Fn-binding proteins bind to Fn to form a bridge to α5 β1 -integrins, which leads to rearrangement of cytoskeletal actin in host cells and uptake of invading S. pyogenes. Recently, several structural analyses of the invasion mechanism showed molecular interactions by which Fn converts from a compact plasma protein to a fibrillar component of the extracellular matrix. After colonization, S. pyogenes must evade the host innate immune system to spread into blood vessels and deeper organs. Some Fn-binding proteins contribute to evasion of host innate immunity, such as the complement system and phagocytosis. In addition, Fn-binding proteins have received focus as non-M protein vaccine candidates, because of their localization and conservation among different M serotypes.Here, we review the roles of Fn-binding proteins in the pathogenesis and speculate regarding possible vaccine antigen candidates. © 2012 Blackwell Publishing Ltd.

  19. The interrelationship between ligand binding and self-association of the folate binding protein

    DEFF Research Database (Denmark)

    Holm, Jan; Schou, Christian; Babol, Linnea N.

    2011-01-01

    The folate binding protein (FBP) regulates homeostasis and intracellular trafficking of folic acid, a vitamin of decisive importance in cell division and growth. We analyzed whether interrelationship between ligand binding and self-association of FBP plays a significant role in the physiology...

  20. Helical propensity in an intrinsically disordered protein accelerates ligand binding

    DEFF Research Database (Denmark)

    Iesmantavicius, Vytautas; Dogan, Jakob; Jemth, Per;

    2014-01-01

    Many intrinsically disordered proteins fold upon binding to other macromolecules. The secondary structure present in the well-ordered complex is often formed transiently in the unbound state. The consequence of such transient structure for the binding process is, however, not clear. The activatio...

  1. Studies of the silencing of Baculovirus DNA binding protein

    NARCIS (Netherlands)

    Quadt, I.; Lent, van J.W.M.; Knebel-Morsdorf, D.

    2007-01-01

    Baculovirus DNA binding protein (DBP) binds preferentially single-stranded DNA in vitro and colocalizes with viral DNA replication sites. Here, its putative role as viral replication factor has been addressed by RNA interference. Silencing of DBP in Autographa californica multiple

  2. Studies of the silencing of Baculovirus DNA binding protein

    NARCIS (Netherlands)

    Quadt, I.; Lent, van J.W.M.; Knebel-Morsdorf, D.

    2007-01-01

    Baculovirus DNA binding protein (DBP) binds preferentially single-stranded DNA in vitro and colocalizes with viral DNA replication sites. Here, its putative role as viral replication factor has been addressed by RNA interference. Silencing of DBP in Autographa californica multiple nucleopolyhedrovir

  3. Conformational thermodynamics of metal-ion binding to a protein

    Science.gov (United States)

    Das, Amit; Chakrabarti, J.; Ghosh, Mahua

    2013-08-01

    Conformational changes in proteins induced by metal-ions play extremely important role in various cellular processes and technological applications. Dihedral angles are suitable conformational variables to describe microscopic conformations of a biomacromolecule. Here, we use the histograms of the dihedral angles to study the thermodynamics of conformational changes of a protein upon metal-ion binding. Our method applied to Ca2+ ion binding to an important metalloprotein, Calmodulin, reveals different thermodynamic changes in different metal-binding sites. The ligands coordinating to Ca2+ ions also play different roles in stabilizing the metal-ion coordinated protein-structure. Metal-ion binding induce remarkable thermodynamic changes in distant part of the protein via modification of secondary structural elements.

  4. Fibronectin binding to protein A-containing staphylococci.

    OpenAIRE

    Doran, J E; Raynor, R H

    1981-01-01

    Fibronectin (Fn) was found to bind to protein A-containing isolates of Staphylococcus aureus, but not to mutant strains devoid of this protein nor to clinical isolates of S. epidermidis. Fn was purified from human plasma by affinity chromatography on gelatin-Sepharose. After elution with 4 M urea, sodium dodecyl sulfate-polyacrylamide gel electrophoresis of purified material detected no immunoglobulin contamination. This purified Fn was radiolabeled with 125I and used in binding assays. Quant...

  5. Theoretical studies of protein-protein and protein-DNA binding rates

    Science.gov (United States)

    Alsallaq, Ramzi A.

    Proteins are folded chains of amino acids. Some of the amino acids (e.g. Lys, Arg, His, Asp, and Glu) carry charges under physiological conditions. Proteins almost always function through binding to other proteins or ligands, for example barnase is a ribonuclease protein, found in the bacterium Bacillus amyloliquefaceus. Barnase degrades RNA by hydrolysis. For the bacterium to inhibit the potentially lethal action of Barnase within its own cell it co-produces another protein called barstar which binds quickly, and tightly, to barnase. The biological function of this binding is to block the active site of barnase. The speeds (rates) at which proteins associate are vital to many biological processes. They span a wide range (from less than 103 to 108 M-1s-1 ). Rates greater than ˜ 106 M -1s-1 are typically found to be manifestations of enhancements by long-range electrostatic interactions between the associating proteins. A different paradigm appears in the case of protein binding to DNA. The rate in this case is enhanced through attractive surface potential that effectively reduces the dimensionality of the available search space for the diffusing protein. This thesis presents computational and theoretical models on the rate of association of ligands/proteins to other proteins or DNA. For protein-protein association we present a general strategy for computing protein-protein rates of association. The main achievements of this strategy is the ability to obtain a stringent reaction criteria based on the landscape of short-range interactions between the associating proteins, and the ability to compute the effect of the electrostatic interactions on the rates of association accurately using the best known solvers for Poisson-Boltzmann equation presently available. For protein-DNA association we present a mathematical model for proteins targeting specific sites on a circular DNA topology. The main achievements are the realization that a linear DNA with reflecting ends

  6. Being a binding site: characterizing residue composition of binding sites on proteins.

    Science.gov (United States)

    Iván, Gábor; Szabadka, Zoltán; Grolmusz, Vince

    2007-12-30

    The Protein Data Bank contains the description of more than 45,000 three-dimensional protein and nucleic-acid structures today. Started to exist as the computer-readable depository of crystallographic data complementing printed articles, the proper interpretation of the content of the individual files in the PDB still frequently needs the detailed information found in the citing publication. This fact implies that the fully automatic processing of the whole PDB is a very hard task. We first cleaned and re-structured the PDB data, then analyzed the residue composition of the binding sites in the whole PDB for frequency and for hidden association rules. Main results of the paper: (i) the cleaning and repairing algorithm (ii) redundancy elimination from the data (iii) application of association rule mining to the cleaned non-redundant data set. We have found numerous significant relations of the residue-composition of the ligand binding sites on protein surfaces, summarized in two figures. One of the classical data-mining methods for exploring implication-rules, the association-rule mining, is capable to find previously unknown residue-set preferences of bind ligands on protein surfaces. Since protein-ligand binding is a key step in enzymatic mechanisms and in drug discovery, these uncovered preferences in the study of more than 19,500 binding sites may help in identifying new binding protein-ligand pairs.

  7. Exploring Protein-Peptide Binding Specificity through Computational Peptide Screening.

    Directory of Open Access Journals (Sweden)

    Arnab Bhattacherjee

    2013-10-01

    Full Text Available The binding of short disordered peptide stretches to globular protein domains is important for a wide range of cellular processes, including signal transduction, protein transport, and immune response. The often promiscuous nature of these interactions and the conformational flexibility of the peptide chain, sometimes even when bound, make the binding specificity of this type of protein interaction a challenge to understand. Here we develop and test a Monte Carlo-based procedure for calculating protein-peptide binding thermodynamics for many sequences in a single run. The method explores both peptide sequence and conformational space simultaneously by simulating a joint probability distribution which, in particular, makes searching through peptide sequence space computationally efficient. To test our method, we apply it to 3 different peptide-binding protein domains and test its ability to capture the experimentally determined specificity profiles. Insight into the molecular underpinnings of the observed specificities is obtained by analyzing the peptide conformational ensembles of a large number of binding-competent sequences. We also explore the possibility of using our method to discover new peptide-binding pockets on protein structures.

  8. Synergistic inhibition of the intrinsic factor X activation by protein S and C4b-binding protein

    NARCIS (Netherlands)

    Koppelman, S.J.

    1995-01-01

    The complement protein C4b-binding protein plays an important role in the regulation of the protein C anticoagulant pathway. C4b-binding protein can bind to protein S, thereby inhibiting the cofactor activity of protein S for activated protein C. In this report, we describe a new role for

  9. Synergistic inhibition of the intrinsic factor X activation by protein S and C4b-binding protein

    NARCIS (Netherlands)

    Koppelman, S.J.

    1995-01-01

    The complement protein C4b-binding protein plays an important role in the regulation of the protein C anticoagulant pathway. C4b-binding protein can bind to protein S, thereby inhibiting the cofactor activity of protein S for activated protein C. In this report, we describe a new role for C4b-bindin

  10. Discodermolide interferes with the binding of tau protein to microtubules.

    Science.gov (United States)

    Kar, Santwana; Florence, Gordon J; Paterson, Ian; Amos, Linda A

    2003-03-27

    We investigated whether discodermolide, a novel antimitotic agent, affects the binding to microtubules of tau protein repeat motifs. Like taxol, the new drug reduces the proportion of tau that pellets with microtubules. Despite their differing structures, discodermolide, taxol and tau repeats all bind to a site on beta-tubulin that lies within the microtubule lumen and is crucial in controlling microtubule assembly. Low concentrations of tau still bind strongly to the outer surfaces of preformed microtubules when the acidic C-terminal regions of at least six tubulin dimers are available for interaction with each tau molecule; otherwise binding is very weak.

  11. High-Fidelity DNA Sensing by Protein Binding Fluctuations

    CERN Document Server

    Tlusty, Tsvi; Libchaber, Albert; 10.1103/PhysRevLett.93.258103

    2010-01-01

    One of the major functions of RecA protein in the cell is to bind single-stranded DNA exposed upon damage, thereby triggering the SOS repair response.We present fluorescence anisotropy measurements at the binding onset, showing enhanced DNA length discrimination induced by adenosine triphosphate consumption. Our model explains the observed DNA length sensing as an outcome of out-of equilibrium binding fluctuations, reminiscent of microtubule dynamic instability. The cascade architecture of the binding fluctuations is a generalization of the kinetic proofreading mechanism. Enhancement of precision by an irreversible multistage pathway is a possible design principle in the noisy biological environment.

  12. Abnormal IGF-Binding Protein Profile in the Bone Marrow of Multiple Myeloma Patients

    DEFF Research Database (Denmark)

    Bieghs, Liesbeth; Brohus, Malene; Kristensen, Ida B;

    2016-01-01

    ), monoclonal gammopathy of undetermined significance (MGUS) (n = 37), and control individuals (n = 15), using ELISA (IGFs) and 125I-IGF1 Western Ligand Blotting (IGFBPs). MGUS and MM patients displayed a significant increase in intact IGFBP-2 (2.5-3.8 fold) and decrease in intact IGFBP-3 (0.6-0.5 fold...

  13. PRELIMINARY STUDY OF EXTRACTABLE PROTEIN BINDING USING MALEIC ANHYDRIDE COPOLYMER

    Institute of Scientific and Technical Information of China (English)

    Thirawan Nipithakul; Ladawan Watthanachote; Nanticha Kalapat

    2012-01-01

    A preliminary study of using maleic anhydride copolymer for protein binding has been carried out.The polymeric films were prepared by compression of the purified resin and annealing the film to induce efficient back formation of the anhydride groups.The properties of the film surface were analyzed by attenuated total reflection Fourier transforms infrared spectroscopy and water contact angle measurements.The protein content was determined by Bradford assay.To obtain optimum conditions,immersion time for protein binding was examined.Results revealed that proteins can be successfully immobilized onto the film surface via covalent linkage.The efficiency of the covalent binding of the extractable protein to maleic anhydride-polyethylene film was estimated at 69.87 μtg/cm2,although the film had low anhydride content (3%) on the surface.

  14. 21 CFR 866.5765 - Retinol-binding protein immunological test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Retinol-binding protein immunological test system....5765 Retinol-binding protein immunological test system. (a) Identification. A retinol-binding protein... the retinol-binding protein that binds and transports vitamin A in serum and urine. Measurement...

  15. Probing binding hot spots at protein-RNA recognition sites.

    Science.gov (United States)

    Barik, Amita; Nithin, Chandran; Karampudi, Naga Bhushana Rao; Mukherjee, Sunandan; Bahadur, Ranjit Prasad

    2016-01-29

    We use evolutionary conservation derived from structure alignment of polypeptide sequences along with structural and physicochemical attributes of protein-RNA interfaces to probe the binding hot spots at protein-RNA recognition sites. We find that the degree of conservation varies across the RNA binding proteins; some evolve rapidly compared to others. Additionally, irrespective of the structural class of the complexes, residues at the RNA binding sites are evolutionary better conserved than those at the solvent exposed surfaces. For recognitions involving duplex RNA, residues interacting with the major groove are better conserved than those interacting with the minor groove. We identify multi-interface residues participating simultaneously in protein-protein and protein-RNA interfaces in complexes where more than one polypeptide is involved in RNA recognition, and show that they are better conserved compared to any other RNA binding residues. We find that the residues at water preservation site are better conserved than those at hydrated or at dehydrated sites. Finally, we develop a Random Forests model using structural and physicochemical attributes for predicting binding hot spots. The model accurately predicts 80% of the instances of experimental ΔΔG values in a particular class, and provides a stepping-stone towards the engineering of protein-RNA recognition sites with desired affinity.

  16. Mapping of ligand-binding cavities in proteins.

    Science.gov (United States)

    Andersson, C David; Chen, Brian Y; Linusson, Anna

    2010-05-01

    The complex interactions between proteins and small organic molecules (ligands) are intensively studied because they play key roles in biological processes and drug activities. Here, we present a novel approach to characterize and map the ligand-binding cavities of proteins without direct geometric comparison of structures, based on Principal Component Analysis of cavity properties (related mainly to size, polarity, and charge). This approach can provide valuable information on the similarities and dissimilarities, of binding cavities due to mutations, between-species differences and flexibility upon ligand-binding. The presented results show that information on ligand-binding cavity variations can complement information on protein similarity obtained from sequence comparisons. The predictive aspect of the method is exemplified by successful predictions of serine proteases that were not included in the model construction. The presented strategy to compare ligand-binding cavities of related and unrelated proteins has many potential applications within protein and medicinal chemistry, for example in the characterization and mapping of "orphan structures", selection of protein structures for docking studies in structure-based design, and identification of proteins for selectivity screens in drug design programs.

  17. Binding mechanisms of intrinsically disordered proteins: theory, simulation, and experiment

    Directory of Open Access Journals (Sweden)

    Luca Mollica

    2016-09-01

    Full Text Available In recent years, protein science has been revolutionized by the discovery of intrinsically disordered proteins (IDPs. In contrast to the classical paradigm that a given protein sequence corresponds to a defined structure and an associated function, we now know that proteins can be functional in the absence of a stable three-dimensional structure. In many cases, disordered proteins or protein regions become structured, at least locally, upon interacting with their physiological partners. Many, sometimes conflicting, hypotheses have been put forward regarding the interaction mechanisms of IDPs and the potential advantages of disorder for protein-protein interactions. Whether disorder may increase, as proposed e.g. in the fly-casting hypothesis, or decrease binding rates, increase or decrease binding specificity, or what role pre-formed structure might play in interactions involving IDPs (conformational selection vs. induced fit, are subjects of intense debate. Experimentally, these questions remain difficult to address. Here, we review experimental studies of binding mechanisms of IDPs using NMR spectroscopy and transient kinetic techniques, as well as the underlying theoretical concepts and numerical methods that can be applied to describe these interactions at the atomic level. The available literature suggests that the kinetic and thermodynamic parameters characterizing interactions involving IDPs can vary widely and that there may be no single common mechanism that can explain the different binding modes observed experimentally. Rather, disordered proteins appear to make combined use of features such as pre-formed structure and flexibility, depending on the individual system and the functional context.

  18. Competing binding of metal ions with protein studied by microdialysis

    Institute of Scientific and Technical Information of China (English)

    GUO; Ming(郭明); KONG; Liang(孔亮); MAO; Xiqin(毛希琴); LI; Xin(历欣); ZOU; Hanfa(邹汉法)

    2002-01-01

    A method has been established to study the competing binding of metal ions with protein by a combined technique of microdialysis with high performance liquid chromatography (HPLC). Ni2+, Cd2+, Zn2+, Cu2+ and human serum albumin (HSA) were chosen as model metal ions and protein. The experimental results show that Ni2+ and Cu2+ share a common primary binding site on HSA, and Zn2+ and Cd2+ share a different common primary binding site from them, but there is a common multi-metal binding site for all of those four metal ions. This method show advantages of fast sampling, easily to be operated and especially to be useful when ideal spectroscopic probes are not available for the study of interaction between protein and metal ions.

  19. Theoretical studies of binding of mannose-binding protein to monosaccharides

    Science.gov (United States)

    Aida-Hyugaji, Sachiko; Takano, Keiko; Takada, Toshikazu; Hosoya, Haruo; Kojima, Naoya; Mizuochi, Tsuguo; Inoue, Yasushi

    2004-11-01

    Binding properties of mannose-binding protein (MBP) to monosaccharides are discussed based on ab initio molecular orbital calculations for cluster models constructed. The calculated binding energies indicate that MBP has an affinity for N-acetyl- D-glucosamine, D-mannose, L-fucose, and D-glucose rather than D-galactose and N-acetyl- D-galactosamine, which is consistent with the biochemical experimental results. Electrostatic potential surfaces at the binding site of four monosaccharides having binding properties matched well with that of MBP. A vacant frontier orbital was found to be localized around the binding site of MBP, suggesting that MBP-monosaccharide interaction may occur through electrostatic and orbital interactions.

  20. Structural Perspectives on the Evolutionary Expansion of Unique Protein-Protein Binding Sites.

    Science.gov (United States)

    Goncearenco, Alexander; Shaytan, Alexey K; Shoemaker, Benjamin A; Panchenko, Anna R

    2015-09-15

    Structures of protein complexes provide atomistic insights into protein interactions. Human proteins represent a quarter of all structures in the Protein Data Bank; however, available protein complexes cover less than 10% of the human proteome. Although it is theoretically possible to infer interactions in human proteins based on structures of homologous protein complexes, it is still unclear to what extent protein interactions and binding sites are conserved, and whether protein complexes from remotely related species can be used to infer interactions and binding sites. We considered biological units of protein complexes and clustered protein-protein binding sites into similarity groups based on their structure and sequence, which allowed us to identify unique binding sites. We showed that the growth rate of the number of unique binding sites in the Protein Data Bank was much slower than the growth rate of the number of structural complexes. Next, we investigated the evolutionary roots of unique binding sites and identified the major phyletic branches with the largest expansion in the number of novel binding sites. We found that many binding sites could be traced to the universal common ancestor of all cellular organisms, whereas relatively few binding sites emerged at the major evolutionary branching points. We analyzed the physicochemical properties of unique binding sites and found that the most ancient sites were the largest in size, involved many salt bridges, and were the most compact and least planar. In contrast, binding sites that appeared more recently in the evolution of eukaryotes were characterized by a larger fraction of polar and aromatic residues, and were less compact and more planar, possibly due to their more transient nature and roles in signaling processes.

  1. TALE proteins bind to both active and inactive chromatin.

    Science.gov (United States)

    Scott, James N F; Kupinski, Adam P; Kirkham, Christopher M; Tuma, Roman; Boyes, Joan

    2014-02-15

    TALE (transcription activator-like effector) proteins can be tailored to bind to any DNA sequence of choice and thus are of immense utility for genome editing and the specific delivery of transcription activators. However, to perform these functions, they need to occupy their sites in chromatin. In the present study, we have systematically assessed TALE binding to chromatin substrates and find that in vitro TALEs bind to their target site on nucleosomes at the more accessible entry/exit sites, but not at the nucleosome dyad. We show further that in vivo TALEs bind to transcriptionally repressed chromatin and that transcription increases binding by only 2-fold. These data therefore imply that TALEs are likely to bind to their target in vivo even at inactive loci.

  2. Relating the shape of protein binding sites to binding affinity profiles: is there an association?

    Directory of Open Access Journals (Sweden)

    Bitter István

    2010-10-01

    Full Text Available Abstract Background Various pattern-based methods exist that use in vitro or in silico affinity profiles for classification and functional examination of proteins. Nevertheless, the connection between the protein affinity profiles and the structural characteristics of the binding sites is still unclear. Our aim was to investigate the association between virtual drug screening results (calculated binding free energy values and the geometry of protein binding sites. Molecular Affinity Fingerprints (MAFs were determined for 154 proteins based on their molecular docking energy results for 1,255 FDA-approved drugs. Protein binding site geometries were characterized by 420 PocketPicker descriptors. The basic underlying component structure of MAFs and binding site geometries, respectively, were examined by principal component analysis; association between principal components extracted from these two sets of variables was then investigated by canonical correlation and redundancy analyses. Results PCA analysis of the MAF variables provided 30 factors which explained 71.4% of the total variance of the energy values while 13 factors were obtained from the PocketPicker descriptors which cumulatively explained 94.1% of the total variance. Canonical correlation analysis resulted in 3 statistically significant canonical factor pairs with correlation values of 0.87, 0.84 and 0.77, respectively. Redundancy analysis indicated that PocketPicker descriptor factors explain 6.9% of the variance of the MAF factor set while MAF factors explain 15.9% of the total variance of PocketPicker descriptor factors. Based on the salient structures of the factor pairs, we identified a clear-cut association between the shape and bulkiness of the drug molecules and the protein binding site descriptors. Conclusions This is the first study to investigate complex multivariate associations between affinity profiles and the geometric properties of protein binding sites. We found that

  3. Characterization of EhCaBP, a calcium-binding protein of Entamoeba histolytica and its binding proteins.

    Science.gov (United States)

    Yadava, N; Chandok, M R; Prasad, J; Bhattacharya, S; Sopory, S K; Bhattacharya, A

    1997-01-01

    A novel calcium-binding protein (EhCaBP) has been recently identified and characterized from the protozoan parasite Entamoeba histolytica. In order to decipher the function of this protein, a few basic properties were investigated and compared with the ubiquitous Ca(2+)-signal transducing protein calmodulin (CaM). Indirect immunofluorescence and immunoprecipitation analyses using specific antibodies against EhCaBP suggest that it is a soluble cytoplasmic protein with no major post-translational modification. EhCaBP did not stimulate cAMP-phosphodiesterase activity, differentiating it from all known CaMs. Affinity chromatography of [35S]methionine-labelled proteins of E. histolytica trophozoites using EhCaBP-sepharose column showed Ca(2+)-dependent binding of a group of proteins. Radiolabelled proteins from the same extract also bound to CaM-sepharose. However, the proteins bound to the two columns were different as revealed by sodium dodecyl sulphate polyacrylamide gel electrophoresis. At least one of the EhCaBP-binding proteins became phosphorylated as revealed by in vivo phosphorylation analysis. The binding-proteins could not be detected in E. invadens (a species that is pathogenic in reptiles) and E. moshkovskii (which is found in the human gut but is not pathogenic), two species in which EhCaBP-like protein has not been found. Two distinct Ca(2+)-dependent protein kinases, which get activated by EhCaBP and CaM respectively, were detected in E. histolytica. These kinases require different levels of Ca2+ for their maximal activities. Affinity chromatography also showed the binding of protein kinase(s) to EhCaBP in a Ca(2+)-dependent manner. Our data suggest that there may be novel Ca(2+)-signal transduction pathway in E. histolytica mediated by EhCaBP.

  4. Selectivity determinants of GPCR-G-protein binding

    DEFF Research Database (Denmark)

    Flock, Tilman; Hauser, Alexander S; Lund, Nadia

    2017-01-01

    The selective coupling of G-protein-coupled receptors (GPCRs) to specific G proteins is critical to trigger the appropriate physiological response. However, the determinants of selective binding have remained elusive. Here we reveal the existence of a selectivity barcode (that is, patterns of ami...

  5. Detergent activation of the binding protein in the folate radioassay

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, S.I.; Holm, J.; Lyngbye, J.

    1982-01-01

    A minor cow's whey protein associated with ..beta..-lactoglobulin is used as binding protein in the competitive radioassay for serum and erythrocyte folate. Seeking to optimize the assay, we tested the performance of binder solutions of increasing purity. The folate binding protein was isolated from cow's whey by means of CM-Sepharose CL-6B cation-exchange chromatography, and further purified on a methotrexate-AH-Sepharose 4B affinity matrix. In contrast to ..beta..-lactoglobulin, the purified protein did not bind folate unless the detergents cetyltrimethylammonium (10 mmol/Ll) or Triton X-100 (1 g/L) were present. Such detergent activation was not needed in the presence of serum. There seems to be a striking analogy between these phenomena and the well-known reactivation of certain purified membrane-derived enzymes by surfactants (lipids/detergents).

  6. ADAM-9 is an insulin-like growth factor binding protein-5 protease produced and secreted by human osteoblasts.

    Science.gov (United States)

    Mohan, Subburaman; Thompson, Garrett R; Amaar, Yousef G; Hathaway, Gary; Tschesche, Harald; Baylink, David J

    2002-12-24

    IGF binding protein-5 (BP-5) is an important bone formation regulator. Therefore, elucidation of the identity of IGF binding protein-5 (BP-5) protease produced by osteoblasts is important for our understanding of the molecular pathways that control the action of BP-5. In this regard, BP-5 protease purified by various chromatographic steps from a conditioned medium of U2 human osteosarcoma cells migrated as a single major band, which comigrated with the protease activity in native PAGE and yielded multiple bands in SDS-PAGE under reducing conditions. N-Terminal sequencing of these bands revealed that three of the bands yielded amino acid sequences that were identical to that of alpha2 macroglobulin (alpha2M). Although alpha2M was produced by human osteoblasts (OBs), it was not found to be a BP-5 protease. Because alpha2M had been shown to complex with ADAM proteases and because ADAM-12 was found to cleave BP-3 and BP-5, we evaluated if one of the members of ADAM family was the BP-5 protease. On the basis of the findings that (1) purified preparations of BP-5 protease from U2 cell CM contained ADAM-9, (2) ADAM-9 is produced and secreted in high abundance by various human OB cell types, (3) purified ADAM-9 cleaved BP-5 effectively while it did not cleave other IGFBPs or did so with less potency, and (4) purified ADAM-9 bound to alpha2M, we conclude that ADAM-9 is a BP-5 protease produced by human OBs.

  7. The biotin repressor: thermodynamic coupling of corepressor binding, protein assembly, and sequence-specific DNA binding.

    Science.gov (United States)

    Streaker, Emily D; Gupta, Aditi; Beckett, Dorothy

    2002-12-03

    The Escherichia coli biotin repressor, an allosteric transcriptional regulator, is activated for binding to the biotin operator by the small molecule biotinyl-5'-AMP. Results of combined thermodynamic, kinetic, and structural studies of the protein have revealed that corepressor binding results in disorder to order transitions in the protein monomer that facilitate tighter dimerization. The enhanced stability of the dimer leads to stabilization of the resulting biotin repressor-biotin operator complex. It is not clear, however, that the allosteric response in the system is transmitted solely through the protein-protein interface. In this work, the allosteric mechanism has been quantitatively probed by measuring the biotin operator binding and dimerization properties of three biotin repressor species: the apo or unliganded form, the biotin-bound form, and the holo or bio-5'-AMP-bound form. Comparisons of the pairwise differences in the bioO binding and dimerization energetics for the apo and holo species reveal that the enhanced DNA binding energetics resulting from adenylate binding track closely with the enhanced assembly energetics. However, when the results for repressor pairs that include the biotin-bound species are compared, no such equivalence is observed.

  8. CLIPZ: a database and analysis environment for experimentally determined binding sites of RNA-binding proteins.

    Science.gov (United States)

    Khorshid, Mohsen; Rodak, Christoph; Zavolan, Mihaela

    2011-01-01

    The stability, localization and translation rate of mRNAs are regulated by a multitude of RNA-binding proteins (RBPs) that find their targets directly or with the help of guide RNAs. Among the experimental methods for mapping RBP binding sites, cross-linking and immunoprecipitation (CLIP) coupled with deep sequencing provides transcriptome-wide coverage as well as high resolution. However, partly due to their vast volume, the data that were so far generated in CLIP experiments have not been put in a form that enables fast and interactive exploration of binding sites. To address this need, we have developed the CLIPZ database and analysis environment. Binding site data for RBPs such as Argonaute 1-4, Insulin-like growth factor II mRNA-binding protein 1-3, TNRC6 proteins A-C, Pumilio 2, Quaking and Polypyrimidine tract binding protein can be visualized at the level of the genome and of individual transcripts. Individual users can upload their own sequence data sets while being able to limit the access to these data to specific users, and analyses of the public and private data sets can be performed interactively. CLIPZ, available at http://www.clipz.unibas.ch, aims to provide an open access repository of information for post-transcriptional regulatory elements.

  9. CAG trinucleotide RNA repeats interact with RNA-binding proteins

    Energy Technology Data Exchange (ETDEWEB)

    McLaughlin, B.A.; Eberwine, J.; Spencer, C. [Univ. of Pennsylvania, Philadelphia, PA (United States)

    1996-09-01

    Genes associated with several neurological diseases are characterized by the presence of an abnormally long trinucleotide repeat sequence. By way of example, Huntington`s disease (HD), is characterized by selective neuronal degeneration associated with the expansion of a polyglutamine-encoding CAG tract. Normally, this CAG tract is comprised of 11-34 repeats, but in HD it is expanded to >37 repeats in affected individuals. The mechanism by which CAG repeats cause neuronal degeneration is unknown, but it has been speculated that the expansion primarily causes abnormal protein functioning, which in turn causes HD pathology. Other mechanisms, however, have not been ruled out. Interactions between RNA and RNA-binding proteins have previously been shown to play a role in the expression of several eukaryotic genes. Herein, we report the association of cytoplasmic proteins with normal length and extended CAG repeats, using gel shift and LJV crosslinking assays. Cytoplasmic protein extracts from several rat brain regions, including the striatum and cortex, sites of neuronal degeneration in HD, contain a 63-kD RNA-binding protein that specifically interacts with these CAG-repeat sequences. These protein-RNA interactions are dependent on the length of the CAG repeat, with longer repeats binding substantially more protein. Two CAG repeat-binding proteins are present in human cortex and striatum; one comigrates with the rat protein at 63 kD, while the other migrates at 49 kD. These data suggest mechanisms by which RNA-binding proteins may be involved in the pathological course of trinucleotide repeat-associated neurological diseases. 47 refs., 5 figs.

  10. Urinary Biomarkers IGFBP7 and TIMP-2 for the Diagnostic Assessment of Transient and Persistent Acute Kidney Injury in Critically Ill Patients.

    Science.gov (United States)

    Daubin, Delphine; Cristol, Jean Paul; Dupuy, Anne Marie; Kuster, Nils; Besnard, Noémie; Platon, Laura; Buzançais, Aurèle; Brunot, Vincent; Garnier, Fanny; Jonquet, Olivier; Klouche, Kada

    2017-01-01

    The capability of urinary TIMP-2 (tissue inhibitor of metalloproteinase) and IGFBP7 (insulin-like growth factor binding protein)-NephroCheck Test (NC) = ([TIMP-2] x [IGFBP7]) / 1000)-to predict renal recovery from acute kidney injury (AKI) has been poorly studied. The aim of this study was to assess the performance of measurements of ([TIMP-2] x [IGFBP7]) / 1000) over 24 hours to differentiate transient from persistent AKI. Of 460 consecutive adult patients admitted to the ICU, 101 were prospectively studied: 56 men, 62 (52-71) years old. A fresh urine sample was collected at H0, H4, H12 and H24 to determine ([TIMP-2] x [IGFBP7]) / 1000) levels. Areas under the curves of Delta NC H4-Ho and H12-H4 and serum creatinine (sCr) for detection of AKI recovery were compared. Forty-one (40.6%) patient were diagnosed with AKI: 27 transient and 14 persistent AKI. At admission (H0), AKI patients had a significantly higher NC score than patients without AKI (0.43 [0.07-2.06] vs 0.15 [0.07-0.35], p = 0.027). In AKI groups, transient AKI have a higher NC, at H0 and H4, than persistent AKI (0.87 [0.09-2.82] vs 0.13 [0.05-0.66] p = 0.035 and 0.13 [0.07-0.61] vs 0.05 [0.02-0.13] p = 0.013). Thereafter, NC level decreased in both AKI groups with a Delta NC score H4-H0 and H12-H4 significantly more important in transient AKI. Roc curves showed however that delta NC scores did not discriminate between transient and persistent AKI. In our population, absolute urinary levels of NC score were higher at early hours after ICU admission (H0 and H4) in transient AKI as compared to persistent AKI patients. NC variations (Delta NC scores) over the first 12 hours may indicate the AKI's evolving nature with a more significant decrease in case of transient AKI but were not able to differentiate transient from persistent AKI.

  11. TATA-binding protein and the retinoblastoma gene product bind to overlapping epitopes on c-Myc and adenovirus E1A protein

    NARCIS (Netherlands)

    Hateboer, G.; Timmers, H.T.M.; Rustgi, A.K.; Billaud, Marc; Veer, L.J. Van 't; Bernards, R.A.

    1993-01-01

    Using a protein binding assay, we show that the amino-teminal 204 amino acids of the c-Myc protein interact di y with a key component of the basal p tdon factor TFID, the TATA box-binding protein (TBP). Essentialy the same region of the c-Myc protein alo binds the product of the retinoblatoma gene,

  12. Natural history of S-adenosylmethionine-binding proteins

    Directory of Open Access Journals (Sweden)

    Mushegian Arcady R

    2005-10-01

    Full Text Available Abstract Background S-adenosylmethionine is a source of diverse chemical groups used in biosynthesis and modification of virtually every class of biomolecules. The most notable reaction requiring S-adenosylmethionine, transfer of methyl group, is performed by a large class of enzymes, S-adenosylmethionine-dependent methyltransferases, which have been the focus of considerable structure-function studies. Evolutionary trajectories of these enzymes, and especially of other classes of S-adenosylmethionine-binding proteins, nevertheless, remain poorly understood. We addressed this issue by computational comparison of sequences and structures of various S-adenosylmethionine-binding proteins. Results Two widespread folds, Rossmann fold and TIM barrel, have been repeatedly used in evolution for diverse types of S-adenosylmethionine conversion. There were also cases of recruitment of other relatively common folds for S-adenosylmethionine binding. Several classes of proteins have unique unrelated folds, specialized for just one type of chemistry and unified by the theme of internal domain duplications. In several cases, functional divergence is evident, when evolutionarily related enzymes have changed the mode of binding and the type of chemical transformation of S-adenosylmethionine. There are also instances of functional convergence, when biochemically similar processes are performed by drastically different classes of S-adenosylmethionine-binding proteins. Comparison of remote sequence similarities and analysis of phyletic patterns suggests that the last universal common ancestor of cellular life had between 10 and 20 S-adenosylmethionine-binding proteins from at least 5 fold classes, providing for S-adenosylmethionine formation, polyamine biosynthesis, and methylation of several substrates, including nucleic acids and peptide chain release factor. Conclusion We have observed several novel relationships between families that were not known to be

  13. PRBP: Prediction of RNA-Binding Proteins Using a Random Forest Algorithm Combined with an RNA-Binding Residue Predictor.

    Science.gov (United States)

    Ma, Xin; Guo, Jing; Xiao, Ke; Sun, Xiao

    2015-01-01

    The prediction of RNA-binding proteins is an incredibly challenging problem in computational biology. Although great progress has been made using various machine learning approaches with numerous features, the problem is still far from being solved. In this study, we attempt to predict RNA-binding proteins directly from amino acid sequences. A novel approach, PRBP predicts RNA-binding proteins using the information of predicted RNA-binding residues in conjunction with a random forest based method. For a given protein, we first predict its RNA-binding residues and then judge whether the protein binds RNA or not based on information from that prediction. If the protein cannot be identified by the information associated with its predicted RNA-binding residues, then a novel random forest predictor is used to determine if the query protein is a RNA-binding protein. We incorporated features of evolutionary information combined with physicochemical features (EIPP) and amino acid composition feature to establish the random forest predictor. Feature analysis showed that EIPP contributed the most to the prediction of RNA-binding proteins. The results also showed that the information from the RNA-binding residue prediction improved the overall performance of our RNA-binding protein prediction. It is anticipated that the PRBP method will become a useful tool for identifying RNA-binding proteins. A PRBP Web server implementation is freely available at http://www.cbi.seu.edu.cn/PRBP/.

  14. Quantitative analysis of EGR proteins binding to DNA: assessing additivity in both the binding site and the protein

    Directory of Open Access Journals (Sweden)

    Stormo Gary D

    2005-07-01

    Full Text Available Abstract Background Recognition codes for protein-DNA interactions typically assume that the interacting positions contribute additively to the binding energy. While this is known to not be precisely true, an additive model over the DNA positions can be a good approximation, at least for some proteins. Much less information is available about whether the protein positions contribute additively to the interaction. Results Using EGR zinc finger proteins, we measure the binding affinity of six different variants of the protein to each of six different variants of the consensus binding site. Both the protein and binding site variants include single and double mutations that allow us to assess how well additive models can account for the data. For each protein and DNA alone we find that additive models are good approximations, but over the combined set of data there are context effects that limit their accuracy. However, a small modification to the purely additive model, with only three additional parameters, improves the fit significantly. Conclusion The additive model holds very well for every DNA site and every protein included in this study, but clear context dependence in the interactions was detected. A simple modification to the independent model provides a better fit to the complete data.

  15. A new zinc binding fold underlines the versatility of zinc binding modules in protein evolution.

    Science.gov (United States)

    Sharpe, Belinda K; Matthews, Jacqueline M; Kwan, Ann H Y; Newton, Anthea; Gell, David A; Crossley, Merlin; Mackay, Joel P

    2002-05-01

    Many different zinc binding modules have been identified. Their abundance and variety suggests that the formation of zinc binding folds might be relatively common. We have determined the structure of CH1(1), a 27-residue peptide derived from the first cysteine/histidine-rich region (CH1) of CREB binding protein (CBP). This peptide forms a highly ordered zinc-dependent fold that is distinct from known folds. The structure differs from a subsequently determined structure of a larger region from the CH3 region of CBP, and the CH1(1) fold probably represents a nonphysiologically active form. Despite this, the fold is thermostable and tolerant to both multiple alanine mutations and changes in the zinc-ligand spacing. Our data support the idea that zinc binding domains may arise frequently. Additionally, such structures may prove useful as scaffolds for protein design, given their stability and robustness.

  16. RNA-binding region of Macrobrachium rosenbergii nodavirus capsid protein.

    Science.gov (United States)

    Goh, Zee Hong; Mohd, Nur Azmina Syakirin; Tan, Soon Guan; Bhassu, Subha; Tan, Wen Siang

    2014-09-01

    White tail disease (WTD) kills prawn larvae and causes drastic losses to the freshwater prawn (Macrobrachium rosenbergii) industry. The main causative agent of WTD is Macrobrachium rosenbergii nodavirus (MrNV). The N-terminal end of the MrNV capsid protein is very rich in positively charged amino acids and is postulated to interact with RNA molecules. N-terminal and internal deletion mutagenesis revealed that the RNA-binding region is located at positions 20-29, where 80 % of amino acids are positively charged. Substitution of all these positively charged residues with alanine abolished the RNA binding. Mutants without the RNA-binding region still assembled into virus-like particles, suggesting that this region is not a part of the capsid assembly domain. This paper is, to the best of our knowledge, the first to report the specific RNA-binding region of MrNV capsid protein.

  17. Retinoblastoma-binding protein 1 has an interdigitated double Tudor domain with DNA binding activity.

    Science.gov (United States)

    Gong, Weibin; Wang, Jinfeng; Perrett, Sarah; Feng, Yingang

    2014-02-21

    Retinoblastoma-binding protein 1 (RBBP1) is a tumor and leukemia suppressor that binds both methylated histone tails and DNA. Our previous studies indicated that RBBP1 possesses a Tudor domain, which cannot bind histone marks. In order to clarify the function of the Tudor domain, the solution structure of the RBBP1 Tudor domain was determined by NMR and is presented here. Although the proteins are unrelated, the RBBP1 Tudor domain forms an interdigitated double Tudor structure similar to the Tudor domain of JMJD2A, which is an epigenetic mark reader. This indicates the functional diversity of Tudor domains. The RBBP1 Tudor domain structure has a significant area of positively charged surface, which reveals a capability of the RBBP1 Tudor domain to bind nucleic acids. NMR titration and isothermal titration calorimetry experiments indicate that the RBBP1 Tudor domain binds both double- and single-stranded DNA with an affinity of 10-100 μM; no apparent DNA sequence specificity was detected. The DNA binding mode and key interaction residues were analyzed in detail based on a model structure of the Tudor domain-dsDNA complex, built by HADDOCK docking using the NMR data. Electrostatic interactions mediate the binding of the Tudor domain with DNA, which is consistent with NMR experiments performed at high salt concentration. The DNA-binding residues are conserved in Tudor domains of the RBBP1 protein family, resulting in conservation of the DNA-binding function in the RBBP1 Tudor domains. Our results provide further insights into the structure and function of RBBP1.

  18. Carotenoid Antenna Binding and Function in Retinal Proteins

    Science.gov (United States)

    2012-08-13

    REPORT Carotenoid antenna binding and function in retinal proteins 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: Xanthorhodopsin, a proton pump from the...eubacterium Salinibacter ruber, is a unique dual chromophore system that contains, in addition to retinal, the carotenoid salinixanthin as a light... carotenoid ring near the retinal ring. Substitution of the small glycine with bulky tryptophan in this site eliminates binding. The second factor is the 4

  19. A statistical mechanics handbook for protein-ligand binding simulation.

    Science.gov (United States)

    Rocchia, Walter; Bonella, Sara

    2013-01-01

    In this work, the fundamental elements of statistical mechanics underlying the simulation of the protein-ligand binding process, such as statistical ensembles and the concept of microscopic estimators of macroscopic observables and free energy, are summarized in a self consistent fashion. Particular attention is then devoted to the introduction of some mathematical tools that are used in atomistic simulations aimed at estimating binding affinities and free energy profiles, and to the illustration of the origins of the difficulties encountered in this endeavor.

  20. Studies of the silencing of Baculovirus DNA binding protein

    OpenAIRE

    Quadt, I.; Lent, van, J.W.M.; Knebel-Morsdorf, D.

    2007-01-01

    Baculovirus DNA binding protein (DBP) binds preferentially single-stranded DNA in vitro and colocalizes with viral DNA replication sites. Here, its putative role as viral replication factor has been addressed by RNA interference. Silencing of DBP in Autographa californica multiple nucleopolyhedrovirus-infected cells increased expression of LEF-3, LEF-4, and P35. In contrast, expression of the structural genes coding for P39 and polyhedrin was suppressed while expression of genes coding for P1...

  1. Identification of novel cyclic nucleotide binding proteins in Trypanosoma cruzi.

    Science.gov (United States)

    Jäger, Adriana V; De Gaudenzi, Javier G; Mild, Jesica G; Mc Cormack, Bárbara; Pantano, Sergio; Altschuler, Daniel L; Edreira, Martin M

    2014-12-01

    Cyclic AMP has been implicated as second messenger in a wide range of cellular processes. In the protozoan parasite Trypanosoma cruzi, cAMP is involved in the development of the parasite's life cycle. While cAMP effectors have been widely studied in other eukaryotic cells, little is known about cAMP's mechanism of action in T. cruzi. To date, only a cAMP-dependent protein kinase A (PKA) has been cloned and characterised in this parasite; however experimental evidence indicates the existence of cAMP-dependent, PKA-independent events. In order to identify new cAMP binding proteins as potential cAMP effectors, we carried out in silico studies using the predicted T. cruzi proteome. Using a combination of search methods 27 proteins with putative cNMP binding domains (CBDs) were identified. Phylogenetic analysis of the CBDs presented a homogeneous distribution, with sequences segregated into two main branches: one containing kinases-like proteins and the other gathering hypothetical proteins with different function or no other known. Comparative modelling of the strongest candidates provides support for the hypothesis that these proteins may give rise to structurally viable cyclic nucleotide binding domains. Pull-down and nucleotide displacement assays strongly suggest that TcCLB.508523.80 could bind cAMP and eventually be a new putative PKA-independent cAMP effector in T. cruzi.

  2. Chromate Binding and Removal by the Molybdate-Binding Protein ModA.

    Science.gov (United States)

    Karpus, Jason; Bosscher, Michael; Ajiboye, Ifedayo; Zhang, Liang; He, Chuan

    2017-04-04

    Effective and cheap methods and techniques for the safe removal of hexavalent chromate from the environment are in increasingly high demand. High concentrations of hexavalent chromate have been shown to have numerous harmful effects on human biology. We show that the E. coli molybdate-binding protein ModA is a genetically encoded tool capable of removing chromate from aqueous solutions. Although previously reported to not bind chromate, we show that ModA binds chromate tightly and is capable of removing chromate to levels well below current US federal standards. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.