What is IGF-1?
IGF-1 (insulin-like growth factor 1, also called somatomedin C) is the principal mediator of growth hormone’s anabolic and growth-promoting effects in peripheral tissues. Hepatic IGF-1 synthesis downstream of GH-receptor activation is the canonical biomarker readout in growth-hormone-axis pharmacology research.
What the research literature says
IGF-1 is a 70-amino-acid single-chain polypeptide with structural homology to proinsulin. Synthesised predominantly by hepatocytes in response to growth hormone signalling through the GH receptor, secreted into circulation bound to IGF-binding proteins (principally IGFBP-3), and delivered to peripheral tissues where it engages the IGF-1 receptor — a receptor tyrosine kinase structurally related to the insulin receptor.
The relationship between GH and IGF-1 is the central axis of growth-hormone-axis pharmacology research. The Teichman CJC-1295 clinical-pharmacology work documented prolonged GH and IGF-1 secretion as the canonical pharmacological signature of long-acting GHRH analogues (PMID 16352683). The Sackmann-Sala work documented serum protein profile changes during sustained GH/IGF-1 axis activation (PMID 19386527). The Sattler review consolidates the GH/IGF-1 axis biology (PMID 24054930).
The detailed coverage of IGF-1’s role in peptide-research signalling is in the IGF-1 glossary entry.
Why this matters in research context
IGF-1 matters in peptide-research contexts as the standard downstream biomarker readout for GHRH-analogue and GH-secretagogue protocols. Researchers running tesamorelin, CJC-1295, or ipamorelin protocols should expect to track serum IGF-1 elevation as the canonical pharmacodynamic readout — circulating GH measurements are technically more difficult than IGF-1 measurements and IGF-1 provides the integrated time-course-smoothed signal.
Related compounds
- Tesamorelin 10mg — GHRH analogue; IGF-1 is canonical biomarker
- CJC-1295 No DAC 10mg — GHRH analogue; IGF-1 is canonical biomarker
- Ipamorelin 10mg — GH secretagogue; IGF-1 is downstream biomarker
Related research questions
References
- Teichman SL et al. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults. J Clin Endocrinol Metab 2006;91(3):799-805. [PMID 16352683]
- Sackmann-Sala L et al. Activation of the GH/IGF-1 axis by CJC-1295, a long-acting GHRH analog, results in serum protein profile changes in normal adult subjects. Growth Horm IGF Res 2009;19(6):471-477. [PMID 19386527]
- Sattler FR. Growth hormone in the aging male. Best Pract Res Clin Endocrinol Metab 2013;27(4):541-555. [PMID 24054930]
Research-questions pages describe research-context use of peptide-research terminology. They do not constitute medical, veterinary, or clinical advice. Every compound in the Ronin catalog is sold strictly for laboratory and research use only.