叶酸介导的组氨酸环-2-碳掺入核酸：甲状腺激素的影响

Folate-mediated incorporation of ring-2-carbon of histidine into nucleic acids: influence of thyroid hormone.

作者信息

Nair C P, Viswanathan G, Noronha J M

机构信息

Radiation Biology and Biochemistry Division, Bhabha Atomic Research Centre, Bombay, India.

出版信息

Metabolism. 1994 Dec;43(12):1575-8. doi: 10.1016/0026-0495(94)90019-1.

DOI:10.1016/0026-0495(94)90019-1

PMID:7990714

Abstract

Folate-mediated incorporation of [ring-2-14C]histidine into DNA and its modulation under thyroid stress have been studied. Both hyperthyroidism and hypothyroidism decrease the folate-mediated incorporation of the one-carbon unit derived from histidine into DNA significantly, resulting in growth retardation. In concurrence with previous reports, in vivo oxidation of histidine is decreased in hyperthyroidism and increased in hypothyroidism. 5,10-Methylenetetrahydrofolate reductase levels are elevated in hyperthyroidism and decreased in hypothyroidism, whereas methionine synthase levels are decreased in hyperthyroidism and increased in hypothyroidism. It is discussed how in both hyperthyroidism and hypothyroidism folate cofactor-mediated reactions are adversely affected.

摘要

已对叶酸介导的[环-2-¹⁴C]组氨酸掺入DNA及其在甲状腺应激下的调节进行了研究。甲状腺功能亢进和甲状腺功能减退均显著降低叶酸介导的源自组氨酸的一碳单位掺入DNA的量，导致生长发育迟缓。与先前的报道一致，甲状腺功能亢进时组氨酸的体内氧化减少，而甲状腺功能减退时则增加。甲状腺功能亢进时5,10-亚甲基四氢叶酸还原酶水平升高，甲状腺功能减退时降低，而蛋氨酸合酶水平在甲状腺功能亢进时降低，在甲状腺功能减退时升高。本文讨论了甲状腺功能亢进和甲状腺功能减退时叶酸辅助因子介导的反应如何受到不利影响。