title: Insulin-like growth factor I enhances the formation of type I collagen in hydrocortisone-treated human osteoblasts.
abstract: We have studied the effect of insulin-like growth factor I (IGF-I) on the formation of osteocalcin and type I collagen in isolated human osteoblasts. IGF-I at and above 0.1 nM stimulated the formation of type I collagen as measured by the type I procollagen carboxyterminal peptide (PICP), in human osteoblasts, incubated for 72 hrs in serum free conditions. The secretion of osteocalcin was not affected by IGF-I while 1,25(OH)2vitamin D3 significantly enhanced the formation of osteocalcin. When human osteoblast-like cells were incubated with hydrocortisone (1 microM), a significant decrease in the release of both PICP and osteocalcin was seen. Addition of IGF-I to human osteoblasts also treated with hydrocortisone normalized the PICP-formation but did not affect the suppressed osteocalcin-formation. These data indicate that IGF-I reverses selective effects of hydrocortisone on bone.
authors.affiliation: Department of Internal Medicine, University Hospital, Uppsala, Sweden.
authors.forename: K B
authors.initials: KB
authors.lastname: Jonsson
authors.forename: S
authors.initials: S
authors.lastname: Ljunghall
authors.forename: O
authors.initials: O
authors.lastname: Karlström
authors.forename: A G
authors.initials: AG
authors.lastname: Johansson
authors.forename: H
authors.initials: H
authors.lastname: Mallmin
authors.forename: O
authors.initials: O
authors.lastname: Ljunggren
mesh_terms: D002117:Calcitriol / Q000494:pharmacology; D002478:Cells, Cultured; D004357:Drug Synergism; D006801:Humans; D006854:Hydrocortisone / Q000494:pharmacology*; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D010006:Osteoblasts / Q000187:drug effects / Q000378:metabolism*; D011347:Procollagen / Q000096:biosynthesis*
chemical_list: D011347:Procollagen; D007334:Insulin-Like Growth Factor I; D002117:Calcitriol; D006854:Hydrocortisone