Olek Robert A, Samborowska Emilia, Wisniewski Piotr, Wojtkiewicz Pawel, Wochna Krystian, Zielinski Jacek
Department of Athletics, Strength, and Conditioning, Poznan University of Physical Education, Krolowej Jadwigi 27/39, Poznan, 61-871, Poland.
Mass Spectrometry Laboratory, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland.
Nutr Metab (Lond). 2023 Aug 2;20(1):32. doi: 10.1186/s12986-023-00752-1.
Higher circulating levels of trimethylamine N-oxide (TMAO), which is a metabolite that can be produced by the gut microbiota from L-carnitine (LC), have been associated with bone mineral density (BMD). Because LC supplementation can improve bone density and microstructural properties in animal models, this study aimed to examine the effects of 12 weeks of LC supplementation on BMD and selected blood markers involved in bone metabolism of postmenopausal women participating in a resistance training (RT) program.
Twenty-seven postmenopausal women, who had not been treated for osteoporosis, with a total T-score above - 3.0 and no diet differences completed 12 weeks of RT. The participants' diets were supplemented with either 1 g of LC-L-tartrate and 3 g of leucine per day (LC group) or 4 g of leucine per day as a placebo (PLA group), in a double-blind fashion.
After the intervention in the LC group, plasma total carnitine and serum decorin levels were higher than the corresponding preintervention values (p = 0.040 and p = 0.042, respectively). Moreover, plasma TMAO and serum SPARC levels were higher in the LC group than the corresponding postintervention values in the PLA group (p < 0.001 and p = 0.030, respectively). No changes in the BMD were observed after 3 months of the intervention.
Twelve weeks of LC supplementation during RT program increased plasma TMAO levels and appeared to affect signaling molecules, as indicated by the increase in the resting SPARC and decorin levels, with no significant modification in the BMD.
Retrospectively registered at the ClinicalTrials.gov (NCT05120011).
氧化三甲胺（TMAO）是一种可由肠道微生物群从左旋肉碱（LC）产生的代谢物，其循环水平升高与骨矿物质密度（BMD）相关。由于补充LC可改善动物模型的骨密度和微观结构特性，本研究旨在探讨在参与抗阻训练（RT）计划的绝经后女性中，补充12周LC对BMD及参与骨代谢的选定血液标志物的影响。
27名未接受骨质疏松症治疗、总T值高于-3.0且饮食无差异的绝经后女性完成了12周的RT。参与者的饮食以双盲方式每天补充1克LC-L-酒石酸盐和3克亮氨酸（LC组）或每天补充4克亮氨酸作为安慰剂（PLA组）。
LC组干预后，血浆总肉碱和血清核心蛋白聚糖水平高于相应的干预前值（分别为p = 0.040和p = 0.042）。此外，LC组的血浆TMAO和血清富含半胱氨酸的酸性分泌蛋白（SPARC）水平高于PLA组相应的干预后值（分别为p < 0.001和p = 0.030）。干预3个月后未观察到BMD的变化。
RT计划期间补充12周LC可提高血浆TMAO水平，并似乎影响信号分子，静止状态下的SPARC和核心蛋白聚糖水平升高表明了这一点，而BMD无显著改变。
在ClinicalTrials.gov（NCT05120011）进行回顾性注册。
