Comparative studies on the regulation of insulin-like growth factor-binding protein-1 (IGFBP-1) and sex hormone-binding globulin (SHBG) production by insulin and insulin-like growth factors in human hepatoma cells

• Published in: The Journal of steroid biochemistry and molecular biology Vol. 86; no. 2; pp. 197 - 200
• Main Authors: Kalme, T, Koistinen, H, Loukovaara, M, Koistinen, R, Leinonen, P
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.08.2003; Elsevier Science
• Subjects: Biological and medical sciences; Cell Line, Tumor; Dose-Response Relationship, Drug; Gastroenterology. Liver. Pancreas. Abdomen; Gene Expression Regulation - drug effects; Humans; Insulin; Insulin - pharmacology; Insulin-Like Growth Factor Binding Protein 1 - analysis; Insulin-Like Growth Factor Binding Protein 1 - biosynthesis; Insulin-Like Growth Factor I - pharmacology; Insulin-Like Growth Factor II - pharmacology; Insulin-like growth factor-binding protein-1; Insulin-like growth factors; Liver - cytology; Liver. Biliary tract. Portal circulation. Exocrine pancreas; Medical sciences; RNA, Messenger - analysis; Sex hormone-binding globulin; Sex Hormone-Binding Globulin - analysis; Sex Hormone-Binding Globulin - biosynthesis; Somatomedins - pharmacology; Tumors; Insulin-like growth factor-binding protein-1; Sex hormone-binding globulin; Insulin-like growth factors; Insulin; Human; Pancreatic hormone; Sex hormone binding protein; Hepatic disease; Hepatocellular carcinoma; Malignant tumor; Insulin like growth factor binding protein; Insulin like growth factor; Digestive diseases; Comparative study
• ISSN: 0960-0760; 1879-1220
• DOI: 10.1016/S0960-0760(03)00268-1

Production of insulin-like growth factor-binding protein-1 (IGFBP-1) by the liver is efficiently inhibited by insulin both in vivo and in vitro. Consequently, serum IGFBP-1 concentration reflects insulin bioactivity in portal vein. Sex hormone-binding globulin (SHBG) is another insulin-regulated liver-derived protein that has appeared promising in detecting individuals with portal hyperinsulinemia. We compared the regulation of IGFBP-1 and SHBG production by insulin and insulin-like growth factors (IGF-I and IGF-II) in human hepatoma cell cultures. Insulin equipotently inhibited IGFBP-1 and SHBG production, with maximal decrease in culture medium concentrations being about 35% for both proteins during 48 h of culture in serum-free medium. IGF-I and IGF-II also inhibited the IGFBP-1 and SHBG levels. We conclude that IGFBP-1 and SHBG are equally sensitive to ambient insulin concentrations in human hepatoma cell cultures, and the production of both proteins is also attenuated by the IGFs.