Evidence of insulin-like growth factor binding protein-3 proteolysis during growth hormone stimulation testing
| dc.contributor.author | Nwosu, Benjamin U. | |
| dc.contributor.author | Soyka, Leslie A. | |
| dc.contributor.author | Angelescu, Amanda | |
| dc.contributor.author | Lee, Mary M. | |
| dc.date | 2022-08-11T08:10:13.000 | |
| dc.date.accessioned | 2022-08-23T17:00:15Z | |
| dc.date.available | 2022-08-23T17:00:15Z | |
| dc.date.issued | 2011-04-14 | |
| dc.date.submitted | 2011-09-06 | |
| dc.identifier.citation | J Pediatr Endocrinol Metab. 2011;24(3-4):163-7. <a href="http://dx.doi.org/10.1515/JPEM.2011.088">Link to article on publisher's website</a> | |
| dc.identifier.issn | 0334-018X (Linking) | |
| dc.identifier.doi | 10.1515/JPEM.2011.088 | |
| dc.identifier.pmid | 21648284 | |
| dc.identifier.uri | http://hdl.handle.net/20.500.14038/43757 | |
| dc.description.abstract | OBJECTIVES: The ternary complex is composed of insulin-like growth factor (IGF)-I, IGF binding protein (IGFBP)-3 and acid labile subunit (ALS). Growth hormone (GH) promotes IGFBP-3 proteolysis to release free IGF-I, ALS, and IGFBP-3 fragments. Our aim was to determine whether elevated GH levels during GH stimulation testing would trigger IGFBP-3 proteolysis. DESIGN: This prospective study of 10 short prepubertal children (height standard deviation score -2.37 +/- 0.31) used arginine and GH releasing hormone stimulation to study dynamic changes in the ternary complex moieties. IGFBP-3 was measured in two assays: a radioimmunoassay (RIA) that detects both cleaved and intact IGFBP-3; and an immunochemiluminescence assay (ICMA) that detects only intact IGFBP-3. RESULTS: IGFBP-3 measured by RIA increased by 19% (p < 0.05), while IGFBP-3 measured by ICMA did not significantly increase (6.1%). CONCLUSION: The significant increase in IGFBP-3 measured by RIA, but not ICMA, provides evidence of IGFBP-3 proteolysis during acute GH stimulation. | |
| dc.language.iso | en_US | |
| dc.relation | <a href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&list_uids=21648284&dopt=Abstract">Link to Article in PubMed</a> | |
| dc.relation.url | http://dx.doi.org/10.1515/JPEM.2011.088 | |
| dc.subject | Arginine | |
| dc.subject | Child | |
| dc.subject | Dwarfism | |
| dc.subject | Female | |
| dc.subject | Growth Hormone-Releasing Hormone | |
| dc.subject | Human Growth Hormone | |
| dc.subject | Humans | |
| dc.subject | Insulin-Like Growth Factor Binding Protein 3 | |
| dc.subject | Male | |
| dc.subject | Prospective Studies | |
| dc.subject | Puberty | |
| dc.subject | Endocrinology, Diabetes, and Metabolism | |
| dc.subject | Pediatrics | |
| dc.title | Evidence of insulin-like growth factor binding protein-3 proteolysis during growth hormone stimulation testing | |
| dc.type | Journal Article | |
| dc.source.journaltitle | Journal of pediatric endocrinology and metabolism : JPEM | |
| dc.source.volume | 24 | |
| dc.source.issue | 3-4 | |
| dc.identifier.legacycoverpage | https://escholarship.umassmed.edu/peds_pp/7 | |
| dc.identifier.contextkey | 2221121 | |
| html.description.abstract | <p>OBJECTIVES: The ternary complex is composed of insulin-like growth factor (IGF)-I, IGF binding protein (IGFBP)-3 and acid labile subunit (ALS). Growth hormone (GH) promotes IGFBP-3 proteolysis to release free IGF-I, ALS, and IGFBP-3 fragments. Our aim was to determine whether elevated GH levels during GH stimulation testing would trigger IGFBP-3 proteolysis.</p> <p>DESIGN: This prospective study of 10 short prepubertal children (height standard deviation score -2.37 +/- 0.31) used arginine and GH releasing hormone stimulation to study dynamic changes in the ternary complex moieties. IGFBP-3 was measured in two assays: a radioimmunoassay (RIA) that detects both cleaved and intact IGFBP-3; and an immunochemiluminescence assay (ICMA) that detects only intact IGFBP-3.</p> <p>RESULTS: IGFBP-3 measured by RIA increased by 19% (p < 0.05), while IGFBP-3 measured by ICMA did not significantly increase (6.1%).</p> <p>CONCLUSION: The significant increase in IGFBP-3 measured by RIA, but not ICMA, provides evidence of IGFBP-3 proteolysis during acute GH stimulation.</p> | |
| dc.identifier.submissionpath | peds_pp/7 | |
| dc.contributor.department | Department of Cell Biology | |
| dc.contributor.department | Department of Pediatrics, Division of Endocrinology | |
| dc.source.pages | 163-7 |
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