摘要
目的观察蛋氨酸(methionine,Met)负载对大鼠肝细胞同型半胱氨酸代谢酶及相关化合物的影响。方法体外培养BRL(Baffalo rat liver)细胞,将其分为两组,对照组和Met组(20 mmol/L Met作用1h)。采用高效液相色谱法检测同型半胱氨酸(Hcy)、半胱氨酸(Cys)、谷胱甘肽(GSH)、S-腺苷蛋氨酸(SAM)、S-腺苷同型半胱氨酸(SAH)含量,全自动氨基酸分析仪检测培养液中丝氨酸(Ser)、谷氨酸(Glu)、甘氨酸(Gly)、胱氨酸(Cys)、牛磺酸(Tau)的含量,参照文献方法检测细胞内S-腺苷同型半胱氨酸水解酶(SAHH)、胱硫醚-β-合成酶(CBS)、甜菜碱同型半胱氨酸甲基转移酶(BHMT)和蛋氨酸合成酶(MS)的活性。结果蛋氨酸负载后,培养液中Hcy、Cys、Ser和胱氨酸含量显著增加(P<0.05),而Glu、Gly和Tau含量显著减少(P<0.05);细胞内SAM含量显著增加(P<0.05),SAHH活性显著增强(P<0.05),BHMT和MS活性显著减弱(P<0.05)。SAH含量和CBS活性变化不明显。结论蛋氨酸负载可活化大鼠肝细胞中同型半胱氨酸的转硫化途径,同时抑制其再甲基化途径。
Objective To observe the effects of methionine loading on homocysteine metabolic enzymes and related metabolites in rat hepatocytes. Methods BRL rat hepatocytes were cultured in vitro and divided into two groups, including control and methionine group （treated by 20 mmol/L methionine for lh）. Homocysteine （Hey）, cysteine （Cys）, glutathione （GSH）, S-adenosylmethionine （SAM） and S-adenosylhomocysteine （SAH） were assayed by HPLC method, Serine （Set）, glutamate （Glu）, glycine （Gly）, cystine and taurine （Tau） were measured by an automatic amino acids analyzer, and S-adenosylhomocysteine hydrolase （SAHH）, cystathionine-J3-synthase （CBS）, betaine homocysteine methytransferase （BHMT） and methionine synthase （MS） were detected by reported methods. Results After methionine loading, the levels of Hey, Cys, Set increased, while Glu, Gly and Tau decreased significantly in cultured medium; SAM content increased, SAHH activity was enhanced, while BHMT and MS activities were weakened dramatically in rat hepatocytes. No noticeable changes were found in the content of SAH and the activity of CBS in rat hepatocytes. Conclusion Methionine loading could activate Hey transsulfuration pathway, at the same time inhibit remethylation pathway. [ACTA NUTRIMENTA SINICA, 2013,35（6）： 545-- 548]
出处
《营养学报》
CAS
CSCD
北大核心
2013年第6期545-548,共4页
Acta Nutrimenta Sinica
基金
国家自然科学基金青年项目(No.30901184)
