Miller Robert R, Hay Casey M, Striegnitz Theodore R, Honsey Laura E, Coykendall Carrie E, Blacquiere Kevin D
Hillsdale College, Biology Department, Hillsdale, MI 49242-1205, USA.
Comp Biochem Physiol C Toxicol Pharmacol. 2006 Sep;144(1):25-33. doi: 10.1016/j.cbpc.2006.05.005. Epub 2006 May 26.
The effects of exogenous glycine on homocysteine (HoCys)-induced reductions in chick (Gallus gallus) embryo viability, HoCys-induced increases in brain and hepatic membrane lipid peroxidation, HoCys-induced apoptosis (caspase-3 activities) in brain and hepatic tissues, and HoCys-induced reductions in brain and hepatic S-adenosylemethionine (SAM)/S-adenosylhomocysteine (SAH) levels were studied. Exogenous HoCys caused reductions in percent living embryos and reductions in embryo masses. Exogenous glycine attenuated these HoCys-induced reductions in embryo viability. Brain and liver tissues of HoCys-treated embryos exhibited increased caspase-3 activities, increased lipid hydroperoxide (LPO) levels, and reduced levels of long-chain polyunsaturated membrane fatty acids. While exogenous glycine attenuated HoCys-induced changes in brain caspase-3 activities, brain LPO levels, and brain membrane PUFA levels, exogenous glycine was less effective in attenuating HoCys-induced changes in hepatic caspase-3 activities and hepatic membrane PUFA levels. HoCys-induced reductions in SAM/SAH ratios were observed in brains and livers. Exogenous glycine attenuated HoCys-induced reductions in brain SAM/SAH. However, glycine was unable to attenuate HoCys-induced reductions in hepatic SAM/SAH levels.
研究了外源性甘氨酸对同型半胱氨酸（HoCys）诱导的鸡胚活力降低、HoCys诱导的脑和肝细胞膜脂质过氧化增加、HoCys诱导的脑和肝组织细胞凋亡（半胱天冬酶-3活性）以及HoCys诱导的脑和肝组织中S-腺苷甲硫氨酸（SAM）/S-腺苷同型半胱氨酸（SAH）水平降低的影响。外源性HoCys导致存活胚胎百分比降低和胚胎质量下降。外源性甘氨酸减轻了HoCys诱导的胚胎活力降低。经HoCys处理的胚胎的脑和肝组织表现出半胱天冬酶-3活性增加、脂质过氧化氢（LPO）水平升高以及长链多不饱和膜脂肪酸水平降低。虽然外源性甘氨酸减轻了HoCys诱导的脑半胱天冬酶-3活性、脑LPO水平和脑膜多不饱和脂肪酸水平的变化，但外源性甘氨酸在减轻HoCys诱导的肝半胱天冬酶-3活性和肝细胞膜多不饱和脂肪酸水平变化方面效果较差。在脑和肝脏中观察到HoCys诱导的SAM/SAH比值降低。外源性甘氨酸减轻了HoCys诱导的脑SAM/SAH降低。然而，甘氨酸无法减轻HoCys诱导的肝脏SAM/SAH水平降低。
