scholarly journals Consensus Statement on the Standardization and Evaluation of Growth Hormone and Insulin-like Growth Factor Assays

2011 ◽  
Vol 57 (4) ◽  
pp. 555-559 ◽  
Author(s):  
David R Clemmons
Keyword(s):  
Growth Hormone ◽  
Growth Factor ◽  
Normative Data ◽  
Consensus Statement ◽  
International Workshop ◽  
Research Society ◽  
Insulin Like Growth Factor ◽  
Gh Secretion ◽  
Assay Performance ◽  
Igf I

Abstract Growth hormone (GH) and insulin-like growth factor I (IGF-I) measurements are widely used in the diagnosis of disorders of GH secretion, evaluation of children with short stature from multiple causes, management of disorders that lead to nutritional insufficiency or catabolism, and monitoring both GH and IGF-I replacement therapy. Therefore, there is an ongoing need for accurate and precise measurements of these 2 peptide hormones. Representatives of the Growth Hormone Research Society, the IGF Society, and the IFCC convened an international workshop to review assay standardization, requirements for improving assay comparability, variables that affect assay interpretation, technical factors affecting assay performance, assay validation criteria, and the development and use of normative data. Special attention was given to preanalytical conditions, the use of international commutable reference standards, antibody specificity, matrix requirements, QC analysis, and interference by binding proteins. Recommendations for each of these variables were made for measurements of each peptide. Additionally, specific criteria for IGF-I were recommended for age ranges of normative data, consideration of Tanner staging, and consideration of the effect of body mass index. The consensus statement concludes that major improvements are necessary in the areas of assay performance and comparability. This group recommends that a commutable standard for each assay be implemented for worldwide use and that its recommendations be applied to accomplish the task of providing reliable and clinically useful results.

Effects of octreotide on insulin-like growth factor I and metabolic indices in growth hormone-treated growth hormone-deficient patients

1993 ◽  
Vol 129 (5) ◽  
pp. 399-408 ◽  
Author(s):  
Torben Laursen ◽  
Jens OL Jorgensen ◽  
Hans Ørskov ◽  
Jens Møller ◽  
Alan G Harris ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Growth Factor ◽  
Animal Studies ◽  
Area Under The Curve ◽  
Insulin Like Growth Factor ◽  
Gh Secretion ◽  
Factor I ◽  
Igf I ◽  
Growth Factor I ◽  
Igfbp 3

Animal studies have demonstrated that in addition to inhibiting growth hormone (GH) secretion octreotide inhibits in a direct manner hepatic or peripheral insulin-like growth factor I (IGF-I) generation. To test this hypothesis in humans we studied ten GH-deficient patients with frequent blood sampling during 38 h on two occasions. Regular GH therapy was discontinued 72 h prior to each study period. At the start of each study a subcutaneous (sc) injection of GH (3 IU/m2) was given (at 18.00 h). In a single-blinded crossover design, patients received a continuous sc infusion of either octerotide (200 μg/24 h) or placebo (saline). The pharmacokinetics of GH were similar on the two occasions. The area under the curve±sem of serum GH was 142.5±53.6 μg·l−1·h−1 (octreotide) and 144.8±41.8 μg·l−1·h−1 (placebo), (p=0.73); Cmax (μg/l) was 12.5±1.47 (octreotide) and 12.8±1.42 (placebo) (p=0.83), and Tmax (h) was 6.1±0.97 (octreotide) and 5.2±0.65 (placebo) (p=0.49). Growth hormone administration was associated with an increase in serum IGF-I (μg/l), which was identical during the two studies, from 85.3±19.4 to 174.25±30.3 for octreotide and from 97.0±26.4 to 158.8±28.2 for placebo. Mean IGF-I levels (μg/l) were 138.2±25.1 (octreotide) and 134.5±28.6 (placebo) (p=0.78). Similarly, the increase in IGF binding protein 3 (IGFBP-3) levels was identical. Mean IGFBP-3 levels (μg/l) were 2303±323 (octreotide) and 2200±361 (placebo) (p=0.25). Mean insulin levels were significantly lower during octreotide treatment (39.9±17.9 mU/l) than during placebo (59.7±17.8 mU/l) (p<0.05). Mean blood glucose levels were elevated significantly during octreotide infusion (5.98±0.23 mmol/l for octreotide and 5.07±0.16 mmol/l for placebo; p=0.001). Glucagon levels decreased non-significantly (p=0.07) and IGFBP-1 levels tended to increase during infusion of octreotide although not significantly (p=0.41). Levels of the lipid intermediates were identical on the two occasions. Alanine and lactate levels were significantly increased during octreotide infusion. Mean levels of blood alanine (μmol/l) were 470.8±24.2 (octreotide) and 360.1±17.8 (placebo) (p<0.02). Mean levels of blood lactate were 1038±81.0 (octreotide) and 894.4±73.8 (placebo) (p<0.04). We conclude that short-term continuous sc infusion of octreotide has no direct effect on the generation of IGF-I or the pharmacokinetics of exogenous GH in GH-deficient man.

IGF-I does not affect the net increase in GH release in response to arginine

2002 ◽  
Vol 283 (4) ◽  
pp. E702-E710 ◽  
Author(s):  
Ralf Nass ◽  
Suzan S. Pezzoli ◽  
Ian M. Chapman ◽  
James Patrie ◽  
Raymond L. Hintz ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Young Adults ◽  
Growth Factor ◽  
Negative Feedback ◽  
Random Order ◽  
Feedback Effect ◽  
Insulin Like Growth Factor ◽  
Gh Secretion ◽  
Factor I ◽  
Igf I

Arginine stimulates growth hormone (GH) secretion, possibly by inhibiting hypothalamic somatostatin (SS) release. Insulin-like growth factor I (IGF-I) inhibits GH secretion via effects at the pituitary and/or hypothalamus. We hypothesized that if the dominant action of IGF-I is to suppress GH release at the level of the pituitary, then the arginine-induced net increase in GH concentration would be unaffected by an IGF-I infusion. Eight healthy young adults (3 women, 5 men) were studied on day 2 of a 47-h fast for 12 h (35th-47th h) on four occasions. Saline (Sal) or 10 μg · kg−1 · h−1recombinant human IGF-I was infused intravenously for 5 h from 37 to 42 h of the 47-h fast. Arginine (Arg) (30 g iv) or Sal was infused over 30 min during the IGF-I or Sal infusion from 40 to 40.5 h of the fast. Subjects received the following combinations of treatments in random order: 1) Sal + Sal; 2) Sal + Arg; 3) IGF-I + Sal; 4) IGF-I + Arg. Peak GH concentration on the IGF-I + Arg day was ∼45% of that on the Sal + Arg day. The effect of arginine on net GH release was calculated as [(Sal + Arg) − (Sal + Sal)] − [(IGF-I + Arg) − (IGF-I + Sal)]. There was no significant effect of IGF-I on net arginine-induced GH release over control conditions. These findings suggest that the negative feedback effect of IGF-I on GH secretion is primarily mediated at the pituitary level and/or at the hypothalamus through a mechanism different from the stimulatory effect of arginine.

scholarly journals The growth hormone–insulin-like growth factor-I axis in the diagnosis and treatment of growth disorders

2018 ◽  
Vol 7 (6) ◽  
pp. R212-R222 ◽  
Author(s):  
Werner F Blum ◽  
Abdullah Alherbish ◽  
Afaf Alsagheir ◽  
Ahmed El Awwa ◽  
Walid Kaplan ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Growth Factor ◽  
Growth Disorders ◽  
Target Tissue ◽  
Insulin Like Growth Factor ◽  
Gh Therapy ◽  
Gh Secretion ◽  
Cellular Processes ◽  
Igf I ◽  
Endocrine Mechanism

The growth hormone (GH)–insulin-like growth factor (IGF)-I axis is a key endocrine mechanism regulating linear growth in children. While paediatricians have a good knowledge of GH secretion and assessment, understanding and use of measurements of the components of the IGF system are less current in clinical practice. The physiological function of this axis is to increase the anabolic cellular processes of protein synthesis and mitosis, and reduction of apoptosis, with each being regulated in the appropriate target tissue. Measurement of serum IGF-I and IGF-binding protein (IGFBP)-3 concentrations can complement assessment of GH status in the investigation of short stature and contribute to prediction of growth response during GH therapy. IGF-I monitoring during GH therapy also informs the clinician about adherence and provides a safety reference to avoid over-dosing during long-term management.

Consensus on the change of criteria for cure of acromegaly during the last decade

2011 ◽  
Vol 152 (18) ◽  
pp. 703-708 ◽  
Author(s):  
Gábor László Kovács ◽  
Judit Dénes ◽  
Erika Hubina ◽  
László Kovács ◽  
Sándor Czirják ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Growth Factor ◽  
Disease Control ◽  
Short Communication ◽  
Consensus Statement ◽  
Diagnosis And Treatment ◽  
Clinical Aspects ◽  
Insulin Like Growth Factor ◽  
Criteria For Diagnosis ◽  
Definition Of

The Acromegaly Consensus Group redefined the consensus criteria for cure of acromegaly. 74 neurosurgeons and experienced endocrinologists summarized the latest results on diagnosis and treatment of acromegaly. In this consensus statement the reliable growth hormone and insulin-like growth factor-1 assays were established. Definition of disease control was discussed based on the available publications and evidence. This short communication summarizes the clinical aspects of consensus criteria for diagnosis and cure of acromegaly based on the original article. Orv. Hetil., 2011, 152, 703–708.

Effects of refeeding of undernourished and insulin treatment of diabetic neonatal rats on IGF and IGFBP

1996 ◽  
Vol 271 (2) ◽  
pp. E223-E231 ◽  
Author(s):  
L. Goya ◽  
F. Rivero ◽  
M. A. Martin ◽  
R. Arahuetes ◽  
E. R. Hernandez ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Body Weight ◽  
Growth Factor ◽  
Mrna Expression ◽  
Insulin Treatment ◽  
Diabetic Rats ◽  
Insulin Like Growth Factor ◽  
Neonatal Rats ◽  
Igf I ◽  
Serum Gh

The effect of refeeding and insulin treatment of undernourished and diabetic neonatal rats, respectively, on the regulation of insulin-like growth factor (IGF) and insulin-like growth factor binding protein (IGFBP) was investigated. The changes in body weight, insulinemia, glycemia, serum IGF-I, and growth hormone (GH) as well as the increase of the 30-kDa IGFBP in undernourished and diabetic neonatal rats previously shown elsewhere were reversed by refeeding and insulin treatment, respectively. Also, changes in liver mRNA expression of IGF-I and-II and IGFBP-1 and -2 were restored in refed undernourished and IGF-I and IGFBP-1 levels recovered in insulin-treated diabetic rats. However, serum GH was still below normal after rehabilitation in both situations. Thus the present results support the idea of a GH-independent IGF/ IGFBP regulation mediated by a balance of insulin and nutrients as has already been suggested in previous neonatal studies.

Longitudinal bone growth in vitro: effects of insulin-like growth factor I and growth hormone

1991 ◽  
Vol 124 (5) ◽  
pp. 602-607 ◽  
Author(s):  
Ben A. A. Scheven ◽  
Nicola J. Hamilton
Keyword(s):  
Growth Hormone ◽  
Growth Factor ◽  
Bone Growth ◽  
Long Bone ◽  
Long Bones ◽  
Insulin Like Growth Factor ◽  
Serum Free ◽  
Factor I ◽  
Igf I

Abstract. Longitudinal growth was studied using an in vitro model system of intact rat long bones. Metatarsal bones from 18- and 19-day-old rat fetuses, entirely (18 days) or mainly (19 days) composed of chondrocytes, showed a steady rate of growth and radiolabelled thymidine incorporation for at least 7 days in serum-free media. Addition of recombinant human insulin-like growth factor-I to the culture media resulted in a direct stimulation of the longitudinal growth. Recombinant human growth hormone was also able to stimulate bone growth, although this was generally accomplished after a time lag of more than 2 days. A monoclonal antibody to IGF-I abolished both the IGF-I and GH-stimulated growth. However, the antibody had no effect on the growth of the bone explants in control, serum-free medium. Unlike the fetal long bones, bones from 2-day-old neonatal rats were arrested in their growth after 1-2 days in vitro. The neonatal bones responded to IGF-I and GH in a similar fashion as the fetal bones. Thus in this study in vitro evidence of a direct effect of GH on long bone growth via stimulating local production of IGF by the growth plate chondrocytes is presented. Furthermore, endogenous growth factors, others than IGFs, appear to play a crucial role in the regulation of fetal long bone growth.

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