IGF-1
Insulin-like growth factor 1 — the main downstream mediator of growth hormone effects.
Insulin-like growth factor 1 (IGF-1, also called somatomedin C) is a 70-amino-acid protein produced primarily in the liver in response to growth hormone (GH) stimulation. IGF-1 mediates most of the systemic effects attributed to GH: tissue growth, anabolism, glucose handling, and cell proliferation. Because IGF-1 has a much longer half-life than GH itself (hours vs minutes), serum IGF-1 is the standard biomarker for assessing GH status — a single morning IGF-1 reading is more clinically useful than a single GH reading. Reference ranges are age- and sex-stratified.
- GlossaryGHRH
Growth hormone-releasing hormone, the hypothalamic peptide that triggers GH release.
- BiomarkerIGFBP-3 low
Insulin-like growth factor binding protein 3 binds and modulates IGF-1. Low IGFBP-3 alongside low IGF-1 indicates GH-axis suppression; differential diagnosis matters.
- ResearchTesamorelin 10 mg
Tesamorelin is an approved GHRH analogue. The research-grade form is used widely in GH-axis, lipid-metabolism, and hepatic-fat research.
- ResearchIGF-1 LR3 1 mg
Long R3 IGF-1 — an engineered IGF-1 analogue with reduced affinity for IGF-binding proteins and extended plasma half-life. Widely used research reagen
- BiomarkerDHEA-S 80 µg/dL
Dehydroepiandrosterone sulphate at 80 µg/dL in a man in his 40s is below the typical age-matched range. What DHEA-S measures, why the literature treats it as a global endocrine marker, and what its decline means.