Smith E E, Ferguson V L, Simske S J, Gayles E C, Pagliassotti M J
BioServe Space Technologies, University of Colorado, Boulder 80309, USA.
Biomed Sci Instrum. 2000;36:385-90.
Diets high in fat and/or sucrose decrease whole bone mechanical properties and mineralization. This study examines the impact on rat bone mechanical properties and composition of age and diets (a) low in fat, (b) high in sucrose, and (c) high in fat. Sprague-Dawley rats aged 3 weeks (weanling [W]; n = 42), 8 weeks (young [Y]; n = 42), 16 weeks (teenage [T]; n = 39) and 56 weeks (old [O]; n = 40) were randomly assigned to groups: low fat, high sucrose and high fat with n = 12-16 per group. All animals were fed a purified low-fat, high starch diet for two weeks, and fed a low fat (STD), high sucrose (HSD), or high-fat (HFD) for five additional weeks. After sacrifice, the femurs were harvested and non-osseous tissue was removed. The bones were dried at 25 degrees C for 48 hours. Length and the periosteal minimum and maximum diameter (D-min and D-max) at the mid-diaphysis of the femurs were measured with Vernier calipers. The femurs were rehydrated and tested via three-point flexure. Bones were weighed after drying at 105 degrees C (48 hours; Dry-M) and 800 degrees C (24 hours; Ash-M). Percent mineralization (%Min) was calculated as Ash-M/Dry-M X 100%. Length, D-min and D-max, Dry-M and Ash-M all significantly (p < 0.05) increased with age (W < Y < T < O) within each group. %Min and stiffness were significantly greater in [O] than in the younger femurs. No significant results were seen in any age group due to varying diet. These results indicate that five weeks of high fat or high sucrose diet feeding does not affect whole bone size, composition or mechanical properties. Whether a longer dietary period or different diet composition would elicit changes requires further study.
高脂肪和/或高蔗糖饮食会降低全骨的力学性能和矿化程度。本研究考察了年龄以及（a）低脂肪、（b）高蔗糖、（c）高脂肪饮食对大鼠骨骼力学性能和组成的影响。将3周龄（断奶期[W]；n = 42）、8周龄（幼年期[Y]；n = 42）、16周龄（青少年期[T]；n = 39）和56周龄（老年期[O]；n = 40）的斯普拉格-道利大鼠随机分为几组：低脂组、高蔗糖组和高脂肪组，每组12 - 16只。所有动物先喂饲纯化的低脂、高淀粉饮食两周，然后再分别喂饲低脂（STD）、高蔗糖（HSD）或高脂肪（HFD）饮食五周。处死后，取出股骨并去除非骨组织。将骨骼在25摄氏度下干燥48小时。用游标卡尺测量股骨骨干中部的长度以及骨膜最小和最大直径（D - min和D - max）。将股骨重新水化并通过三点弯曲试验进行测试。在105摄氏度（48小时；干重 - M）和800摄氏度（24小时；灰分 - M）干燥后对骨骼称重。矿化百分比（%Min）计算为灰分 - M/干重 - M×100%。每组中，长度、D - min和D - max、干重 - M和灰分 - M均随年龄（W < Y < T < O）显著（p < 0.05）增加。老年期股骨的%Min和硬度显著高于较年轻的股骨。不同饮食对任何年龄组均未产生显著影响。这些结果表明，五周的高脂肪或高蔗糖饮食喂养不会影响全骨的大小、组成或力学性能。更长的饮食期或不同的饮食组成是否会引起变化需要进一步研究。
