Serum Sex Hormones, IGF-1, and IGFBP3 Exert a Sexually Dimorphic Effect on Lean Body Mass in Aging

• Published in: The journals of gerontology. Series A, Biological sciences and medical sciences Biological sciences and medical sciences, 2003-07, Vol.58 (7), p.M648-M652
• Main Authors: Waters, Debra L., Yau, C. Lillian, Montoya, George D., Baumgartner, Richard N.
• Format: Article
• Language: English
• Subjects: Adipose Tissue - anatomy & histology; Aged; Aged, 80 and over; Aging; Aging - physiology; Body Composition - physiology; Estrogen Replacement Therapy; Female; Gonadal Steroid Hormones - blood; Hormones; Humans; Insulin-Like Growth Factor Binding Protein 3 - blood; Insulin-Like Growth Factor I - analysis; Male; Men; Older people; Organ Size; Sex Characteristics; Testosterone - blood; Women
• ISSN: 1079-5006; 1758-535X
• DOI: 10.1093/gerona/58.7.M648

Background. Endogenous and exogenous sex hormones affect changes in body composition during aging via independent and dependent effects on the growth hormone/insulin-like growth factor–1 (GH/IGF-1) axis and associated binding proteins (BP). Methods. Fasting serum IGF-1, IGFBP3, testosterone, estrone, and sex hormone binding globulin were analyzed in 48 women on hormone replacement (HRT) (unopposed oral estrogen, HRT+, \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(74.0\ {\pm}\ 6\ years\) \end{document}), 135 women not on HRT (HRT−, \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(77.3\ {\pm}\ 7\ years\) \end{document}), and 128 healthy men (men, \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(77.7\ {\pm}\ 6\ years\) \end{document}). Total lean body mass (LBM) and total fat were measured by dual energy X-ray absorptiometry. Results. Total LBM decreased with age in all groups (\batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathit{p}\ {=}.05\) \end{document}). LBM was greater, and IGF-1, IGFBP3, and testosterone were lower in HRT+ versus HRT− women (\batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathit{p}\ {=}.02\) \end{document}, \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathit{p}\ {=}.01\) \end{document}, \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathit{p}\ {=}.05\) \end{document}, and \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathit{p}\ {=}.04\) \end{document}, respectively). LBM in men was positively related to IGF-1 (\batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \beg