Authors: Berrigan D, Lavigne JA, Perkins SN, Nagy TR, Barrett JC, Hursting SD
Title: Phenotypic effects of calorie restriction and insulin-like growth factor-1 treatment on body composition and bone mineral density of C57BL/6 mice: implications for cancer prevention.
Journal: In Vivo 19(4):667-74
Date: 2005 Jul-Aug
Abstract: BACKGROUND: Calorie restriction (CR) inhibits carcinogenesis and delays aging. Some anti-carcinogenic effects of CR are mediated by decreased circulating insulin-like growth factor-1 (IGF-1); however, IGF-1 also plays an important role in regulating growth and bone density. MATERIALS AND METHODS: We quantified tradeoffs involving the CR/IGF-1 axis in C57BL/6 mice by examining body composition and bone characteristics in ad libitum fed, 20, 30 or 40% CR mice that received placebo or recombinant murine IGF-1 delivered with a time-release pellet. After 26 days, carcasses were scanned with a PIXImus II dual-energy X-ray absorptiometer. RESULTS: CR reduced body weight and percent body fat and had non-linear effects on bone density. IGF-1 restored bone density to control levels or greater in the CR mice. CONCLUSION: Cancer prevention efforts based on CR and down-regulation of the IGF-1 pathway will require consideration of deleterious effects on bone.
Last Modified: 03 Sep 2013