Hagen T M, Wierzbicka G T, Sillau A H, Bowman B B, Jones D P
Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322.
Am J Physiol. 1990 Oct;259(4 Pt 1):G524-9. doi: 10.1152/ajpgi.1990.259.4.G524.
Plasma glutathione (GSH) concentration in rats increased from approximately 15 to 30 microM after administration of GSH either as a liquid bolus (30 mumol) or mixed (2.5-50 mg/g) in AIN-76 semisynthetic diet. GSH concentration was maximal at 90-120 min after GSH administration and remained high for over 3 h. Administration of the amino acid precursors of GSH had little or no effect on plasma GSH values, indicating that GSH catabolism and resynthesis do not account for the increased GSH concentration seen. Inhibition of GSH synthesis and degradation by L-buthionine-[S,R]-sulfoximine and acivicin showed that the increased plasma GSH came mostly from absorption of intact GSH instead of from its metabolism. Plasma protein-bound GSH also increased after GSH administration, with a time course similar to that observed for free plasma GSH. Thus dietary GSH can be absorbed intact and results in a substantial increase in blood plasma GSH. This indicates that oral supplementation may be useful to enhance tissue availability of GSH.
给大鼠静脉注射液体推注形式的谷胱甘肽（GSH）（30 μmol）或在AIN - 76半合成饲料中混合（2.5 - 50 mg/g）GSH后，大鼠血浆中谷胱甘肽（GSH）浓度从约15 μM增加到30 μM。在给予GSH后90 - 120分钟时，GSH浓度达到最大值，并在3小时以上保持较高水平。给予GSH的氨基酸前体对血浆GSH值几乎没有影响，这表明GSH的分解代谢和再合成并不能解释所观察到的GSH浓度升高。用L - 丁硫氨酸 - [S，R] - 亚砜胺和阿西维辛抑制GSH合成和降解表明，血浆中GSH升高主要来自完整GSH的吸收，而非其代谢。给予GSH后，血浆蛋白结合的GSH也增加，其时间进程与游离血浆GSH相似。因此，膳食中的GSH可以完整吸收，并导致血浆GSH大幅增加。这表明口服补充GSH可能有助于提高组织中GSH的可利用性。
