Debieu D, Deschavanne P J, Malaise E P
Laboratoire de Radiobiologie Cellulaire, Unité INSERM 247, Institut Gustave-Roussy, Villejuif, France.
Clin Chim Acta. 1987 Dec;170(2-3):161-8. doi: 10.1016/0009-8981(87)90124-0.
The activity and the kinetic properties of glutathione synthetase and the concentrations of non-protein bound thiols of the gamma-glutamyl cycle were measured in 11 human fibroblast cell strains. Six of these strains were derived from patients suffering from 5-oxoprolinuria, a recessive genetic disease characterized by a deficiency in glutathione synthetase; the other cell strains were derived from healthy heterozygous or homozygous relatives of the patients. The glutathione synthetase activities of homozygous deficient strains were 1/3 of control values while those of heterozygous strains were 2/3 of control values. The total thiol concentration was lower in only 3 of the 6 deficient homozygotes and that of glutathione (GSH) was lower in only 4 of the 6 deficient homozygotes. This lower GSH level was at least partly offset by an accumulation of gamma-glutamylcysteine, a precursor of GSH, which is almost completely absent from control cells. The total quantities of thiols and GSH in plateau phase cells were about 50% and 30% respectively of the levels in growth phase cells. Approximately 80% of the GSH was in the reduced form in both quiescent and growing cells.
在11株人成纤维细胞系中测定了谷胱甘肽合成酶的活性和动力学特性以及γ-谷氨酰循环中非蛋白结合硫醇的浓度。其中6株细胞系来自患有5-氧脯氨酸尿症的患者，这是一种隐性遗传病，其特征是谷胱甘肽合成酶缺乏；其他细胞系来自患者的健康杂合子或纯合子亲属。纯合缺陷型细胞系的谷胱甘肽合成酶活性为对照值的1/3，而杂合子细胞系的活性为对照值的2/3。6例纯合缺陷型患者中只有3例的总硫醇浓度较低，6例纯合缺陷型患者中只有4例的谷胱甘肽（GSH）浓度较低。GSH水平的降低至少部分被γ-谷氨酰半胱氨酸（GSH的前体）的积累所抵消，对照细胞中几乎完全没有γ-谷氨酰半胱氨酸。平台期细胞中硫醇和GSH的总量分别约为生长阶段细胞中水平的50%和30%。在静止细胞和生长细胞中，约80%的GSH处于还原形式。
