Cyphert Erika L, Liu Chongshan, Morales Angie L, Nixon Jacob C, Blackford Emily, Garcia Matthew, Cevallos Nicolas, Turnbaugh Peter J, Brito Ilana L, Booth Sarah L, Hernandez Christopher J
Department of Orthopaedic Surgery, University of California San Francisco, 513 Parnassus Avenue, San Francisco, CA 94143, United States.
Sibley School of Mechanical & Aerospace Engineering, Cornell University, 124 Hoy Road, Ithaca, NY 14853, United States.
JBMR Plus. 2024 Jun 18;8(8):ziae082. doi: 10.1093/jbmrpl/ziae082. eCollection 2024 Aug.
In a recent study examining the effects of manipulating the gut microbiome on bone, a control group of mice in which the microbiome was altered using a non-caloric, aspartame-based sweetener resulted in whole bone strength being 40% greater than expected from geometry alone, implicating enhanced bone tissue strength. However, the study was not designed to detect changes in bone in this control group and was limited to young male mice. Here we report a replication study examining how changes in the gut microbiome caused by aspartame-based sweetener influence bone. Male and female C57Bl/6 J mice were untreated or treated with a high dose of sweetener (10 g/L) in their drinking water from either 1 to 4 mo of age (young cohort; = 80) or 1 to 22 mo of age (aged cohort; = 52). Sweetener did not replicate the modifications to the gut microbiome observed in the initial study and did not result in an increase in bone tissue strength in either sex at either age. Aged male mice dosed with sweetener had larger bones (+17% femur section modulus, <.001) and greater whole bone strength (+22%, =.006) but the increased whole bone strength was explained by the associated increase in body mass (+9%, <.001). No differences in body mass, whole bone strength, or femoral geometry were associated with sweetener dosing in males from the young cohort or females at either age. As we were unable to replicate the gut microbiota observed in the initial experiment, it remains unclear if changes in the gut microbiome can enhance bone tissue strength. Although prior work studying gut microbiome-induced changes in bone with oral antibiotics has been highly repeatable, the current study highlights the variability of nutritional manipulations of the gut microbiota in mice.
在最近一项研究肠道微生物群操纵对骨骼影响的实验中,使用非热量、基于阿斯巴甜的甜味剂改变微生物群的小鼠对照组,其全骨强度比仅根据几何形状预期的高出40%,这意味着骨组织强度增强。然而,该研究并非旨在检测该对照组骨骼的变化,且仅限于年轻雄性小鼠。在此,我们报告一项重复研究,探究基于阿斯巴甜的甜味剂引起的肠道微生物群变化如何影响骨骼。将雄性和雌性C57Bl/6 J小鼠分为未处理组,以及从1至4月龄(年轻组;n = 80)或1至22月龄(老年组;n = 52)开始在饮用水中给予高剂量甜味剂(10 g/L)的处理组。甜味剂并未重现初始研究中观察到的对肠道微生物群的改变,且在任何年龄的任何性别中均未导致骨组织强度增加。给予甜味剂的老年雄性小鼠骨骼更大(股骨截面模量增加17%,P <.001)且全骨强度更高(增加22%,P = 0.006),但全骨强度的增加是由体重的相应增加(增加9%,P <.001)所解释的。年轻组雄性小鼠或任何年龄的雌性小鼠中,体重、全骨强度或股骨几何形状均未因给予甜味剂而出现差异。由于我们无法重现初始实验中观察到的肠道微生物群,目前尚不清楚肠道微生物群的变化是否能够增强骨组织强度。尽管先前使用口服抗生素研究肠道微生物群诱导的骨骼变化的工作具有高度可重复性,但当前研究突出了小鼠肠道微生物群营养操纵的变异性。