Increased cortical bone content of insulin-like growth factors in acromegalic patients

• Published in: The journal of clinical endocrinology and metabolism 1999, Vol.84 (1), p.123-127
• Main Authors: UELAND, T, BOLLERSLEV, J, HANSEN, T. B, EBBESEN, E. N, MOSEKILDE, L, BRIXEN, K, FLYVBJERG, A, DJØSELAND, O
• Format: Article
• Language: English
• Subjects: Acromegaly - metabolism; Adult; Age Factors; Aged; Biological and medical sciences; Bone and Bones - chemistry; Endocrinopathies; Female; Humans; Hypothalamus. Hypophysis. Epiphysis (diseases); Insulin-Like Growth Factor Binding Protein 3 - analysis; Insulin-Like Growth Factor Binding Protein 5 - analysis; Male; Medical sciences; Middle Aged; Non tumoral diseases. Target tissue resistance. Benign neoplasms; Osteocalcin - analysis; Somatomedins - analysis
• ISSN: 0021-972X; 1945-7197
• DOI: 10.1210/jc.84.1.123

To investigate cortical bone composition and the role of the insulin-like growth factor (IGF) system in active acromegaly, iliac crest bone biopsies were obtained from 15 patients (3 women and 12 men), aged 21-64 yr (mean, 45.6 yr), and 25 age- and sex-matched controls (8 women and 17 men), aged 22-66 yr (mean, 44.6 yr). Levels of IGF-I, IGF-II, IGF-binding protein-3 (IGFBP-3), IGFBP-5, and total protein were determined in extracts obtained after ethylenediamine tetraacetate and guanidine hydrochloride extraction. Osteocalcin and calcium were determined in extracts after HCl hydrolysis. Cortical bone contents of IGF-I, IGF-II, and IGFBP-5 were significantly elevated in the acromegalic patients compared with control values [91% (P < 0.001), 44% (P < 0.04), and 115% (P < 0.004), respectively]. There was no significant difference in IGFBP-3, osteocalcin, protein, and calcium between patients and controls. This study suggests that the increased levels of growth factors in cortical bone from acromegalics is a reflection of local production, secondary to a chronic systemic excess of GH and IGF-I.