目标:骨骼容易受到铁稳态波动的影响,因为缺铁和超负荷都与人类骨骼强度差有关。在老鼠身上,然而,报告了不一致的结果,可能是由于不同的饮食设置或遗传背景。这里,我们评估了不同高铁和低铁饮食对六种近交系小鼠骨骼的影响(C57BL/6J,A/J,BALB/cJ,AKR/J,C3H/HeJ,和DBA/2J)。
方法:小鼠在断奶6-8周后接受高铁(20,000ppm)或低铁饮食(〜10ppm)。对于C57BL/6J男性,我们使用了两种含铁量相似的饮食设置,然而,矿物质和维生素的营养成分不同,要么丰富(“TUD研究”),要么较差(“UCLA研究”)。牺牲之后,肝脏,分析血液和骨参数以及血清中的骨转换标志物。
结果:在加州大学洛杉矶分校研究的高铁饮食中,几乎所有小鼠的皮质和骨小梁质量均显着降低,并伴有高骨吸收。铁缺乏没有改变C57BL/6J的骨微结构或更新,A/J,和DBA/2J小鼠,但BALB/cJ骨小梁骨量增加,C3H/HeJ和AKR/J小鼠。与加州大学洛杉矶分校的研究相反,TUD研究中的雄性C57BL/6J小鼠在高铁或低铁饮食下小梁骨量或更新没有任何变化。然而,在高铁饮食的TUD小鼠中皮质骨参数也降低。
结论:因此,这些数据表明,皮质骨比小梁骨更容易发生铁过载,并强调了营养丰富的饮食对于潜在地减轻铁过载对骨的负面影响的重要性.
OBJECTIVE: Bone is susceptible to fluctuations in iron homeostasis, as both iron deficiency and overload are linked to poor bone strength in humans. In mice, however, inconsistent results have been reported, likely due to different diet setups or genetic backgrounds. Here, we assessed the effect of different high and low iron diets on bone in six inbred mouse strains (C57BL/6J, A/J, BALB/cJ, AKR/J, C3H/HeJ, and DBA/2J).
METHODS: Mice received a high (20,000 ppm) or low-iron diet (∼10 ppm) after weaning for 6-8 weeks. For C57BL/6J males, we used two dietary setups with similar amounts of iron, yet different nutritional compositions that were either richer (\"TUD study\") or poorer (\"UCLA study\") in minerals and vitamins. After sacrifice, liver, blood and bone parameters as well as bone turnover markers in the serum were analyzed.
RESULTS: Almost all mice on the UCLA study high iron diet had a significant decrease of cortical and trabecular bone mass accompanied by high bone resorption. Iron deficiency did not change bone microarchitecture or turnover in C57BL/6J, A/J, and DBA/2J mice, but increased trabecular bone mass in BALB/cJ, C3H/HeJ and AKR/J mice. In contrast to the UCLA study, male C57BL/6J mice in the TUD study did not display any changes in trabecular bone mass or turnover on high or low iron diet. However, cortical bone parameters were also decreased in TUD mice on the high iron diet.
CONCLUSIONS: Thus, these data show that cortical bone is more susceptible to iron overload than trabecular bone and highlight the importance of a nutrient-rich diet to potentially mitigate the negative effects of iron overload on bone.