Liu Yi Qun, Huang Ling He, Liu Pei Pei, Xing Qing Bin, Han Feng, Wang Qin, Chen Shu Rong, Sugiyama Kimio, Xiang Xue Song, Huang Zhen Wu
Key Laboratory of Trace Element Nutrition of National Health Commission, National Institute of Nutrition and Health, Chinese Center for Disease Control and Prevention, Beijing 100050, China.
Chinese Nutrition Society, Beijing 100022, China.
Biomed Environ Sci. 2021 May 20;34(5):356-363. doi: 10.3967/bes2021.047.
This study aimed to investigate the effects of -dimethylglycine (DMG) on the concentration and metabolism of plasma homocysteine (pHcy) in folate-sufficient and folate-deficient rats.
In this study, 0.1% DMG was supplemented in 20% casein diets that were either folate-sufficient (20C) or folate-deficient (20CFD). Blood and liver of rats were subjected to assays of Hcy and its metabolites. Hcy and its related metabolite concentrations were determined using a liquid chromatographic system.
Folate deprivation significantly increased pHcy concentration in rats fed 20C diet (from 14.19 ± 0.39 μmol/L to 28.49 ± 0.50 μmol/L; < 0.05). When supplemented with DMG, pHcy concentration was significantly decreased (12.23 ± 0.18 μmol/L) in rats fed 20C diet but significantly increased (31.56 ± 0.59 μmol/L) in rats fed 20CFD. The hepatic methionine synthase activity in the 20CFD group was significantly lower than that in the 20C group; enzyme activity was unaffected by DMG supplementation regardless of folate sufficiency. The activity of hepatic cystathionine β-synthase (CBS) in the 20CFD group was decreased but not in the 20C group; DMG supplementation enhanced hepatic CBS activity in both groups, in which the effect was significant in the 20C group but not in the other group.
DMG supplementation exhibited hypohomocysteinemic effects under folate-sufficient conditions. By contrast, the combination of folate deficiency and DMG supplementation has deleterious effect on pHcy concentration.
本研究旨在探讨二甲甘氨酸（DMG）对叶酸充足和叶酸缺乏大鼠血浆同型半胱氨酸（pHcy）浓度及代谢的影响。
在本研究中，在叶酸充足（20C）或叶酸缺乏（20CFD）的20%酪蛋白饮食中添加0.1% DMG。对大鼠的血液和肝脏进行同型半胱氨酸（Hcy）及其代谢产物的检测。使用液相色谱系统测定Hcy及其相关代谢产物的浓度。
叶酸缺乏显著增加了喂食20C饮食大鼠的pHcy浓度（从14.19±0.39μmol/L增至28.49±0.50μmol/L；P<0.05）。补充DMG后，喂食20C饮食的大鼠pHcy浓度显著降低（12.23±0.18μmol/L），而喂食20CFD饮食的大鼠pHcy浓度显著升高（31.56±0.59μmol/L）。20CFD组肝脏甲硫氨酸合酶活性显著低于20C组；无论叶酸是否充足，补充DMG均不影响该酶活性。20CFD组肝脏胱硫醚β合酶（CBS）活性降低，而20C组未降低；补充DMG可增强两组肝脏CBS活性，其中20C组效果显著，另一组不显著。
在叶酸充足的条件下，补充DMG具有降低高同型半胱氨酸血症的作用。相比之下，叶酸缺乏与补充DMG相结合对pHcy浓度有有害影响。
Zotero 插件