Bellisola G, Galassini S, Moschini G, Poli G, Perona G, Guidi G
Laboratory of Clinical Chemistry, C.O.C Valeggio s. M., Italy.
Clin Chim Acta. 1992 Jan 31;205(1-2):75-85. doi: 10.1016/s0009-8981(05)80002-6.
Serum and erythrocyte selenium, erythrocyte and platelet glutathione-peroxidase (GSH-Px) activities, and erythrocyte reduced glutathione (GSH) content were measured in 25 healthy adult individuals before and after daily supplementation with 20 ml of fish oil for 10 weeks. Serum-Se decreased from 0.83 +/- 0.01 mumol/l to 0.75 +/- 0.02 mumol/l (mean +/- S.E.M.) (P less than 0.01); erythrocyte-Se decreased from 4.39 +/- 0.17 nmol/g hemoglobin (Hb) to 2.83 +/- 0.15 nmol/g (P less than 0.001). GSH-Px activities increased both in erythrocytes (6.93 +/- 0.24 iu/g vs 8.18 +/- 0.27 iu/g Hb, P less than 0.01) and in platelets (69.2 +/- 2.8 iu/g vs 90.9 +/- 3.6 iu/g protein, P less than 0.001). The concentration of GSH in erythrocytes fell from 9.56 +/- 0.29 mumol/g Hb to 5.90 +/- 0.30 mumol/g Hb (P less than 0.001). The effects on plasma lipids were evident only for triglycerides (before 1.96 +/- 0.16 mmol/l, after 1.75 +/- 0.14 mmol/l, P less than 0.001). We hypothesise the enrichment of erythrocyte and platelet membranes with polyunsaturated fatty acids (PUFAs), following fish oil intake, can generate increased amounts of lipid peroxides and thus allosterically activate GSH-Px: with time this is harmful for the integrity of the enzyme molecule and Se release may result. We suggest that the Se status of individuals given PUFAs is assessed before and during intake; Se supplements should only be given when serum and/or erythrocyte Se are reduced.
对25名健康成年人在每日补充20毫升鱼油10周前后，测定了血清和红细胞硒、红细胞和血小板谷胱甘肽过氧化物酶（GSH - Px）活性以及红细胞还原型谷胱甘肽（GSH）含量。血清硒从0.83±0.01微摩尔/升降至0.75±0.02微摩尔/升（均值±标准误）（P＜0.01）；红细胞硒从4.39±0.17纳摩尔/克血红蛋白（Hb）降至2.83±0.15纳摩尔/克（P＜0.001）。红细胞（6.93±0.24国际单位/克对8.18±0.27国际单位/克Hb，P＜0.01）和血小板（69.2±2.8国际单位/克对90.9±3.6国际单位/克蛋白质，P＜0.001）中的GSH - Px活性均增加。红细胞中GSH浓度从9.56±0.29微摩尔/克Hb降至5.90±0.30微摩尔/克Hb（P＜0.001）。对血脂的影响仅在甘油三酯方面明显（补充前1.96±0.16毫摩尔/升，补充后1.75±0.14毫摩尔/升，P＜0.001）。我们推测，摄入鱼油后红细胞和血小板膜富含多不饱和脂肪酸（PUFA），会产生更多脂质过氧化物，从而变构激活GSH - Px：随着时间推移，这对酶分子的完整性有害，可能导致硒释放。我们建议在摄入PUFA之前及期间评估个体的硒状态；仅在血清和/或红细胞硒降低时才应补充硒。
