摘要
Objective This study aimed to investigate the effects of N,N-dimethylglycine(DMG) on the concentration and metabolism of plasma homocysteine(pHcy) in folate-sufficient and folate-deficient rats.Methods In this study, 0.1% DMG was supplemented in 20% casein diets that were either folatesufficient(20 C) or folate-deficient(20 CFD). 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.Results Folate deprivation significantly increased pHcy concentration in rats fed 20 C diet(from 14.19 ±0.39 μmol/L to 28.49 ± 0.50 μmol/L;P < 0.05). When supplemented with DMG, pHcy concentration was significantly decreased(12.23 ± 0.18 μmol/L) in rats fed 20 C diet but significantly increased(31.56 ±0.59 μmol/L) in rats fed 20 CFD. The hepatic methionine synthase activity in the 20 CFD group was significantly lower than that in the 20 C group;enzyme activity was unaffected by DMG supplementation regardless of folate sufficiency. The activity of hepatic cystathionine β-synthase(CBS) in the 20 CFD group was decreased but not in the 20 C group;DMG supplementation enhanced hepatic CBS activity in both groups, in which the effect was significant in the 20 C group but not in the other group.Conclusion 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.
基金
supported by the National Natural Science Foundation of China under the Grant No. 81973048
a Grant-in-Aid for Scientific Research from the Ministry of Education, Science, Culture, Sports and Technology of Japan [JSPS-C-21580137]。
