Lenton Kevin J, Sané Alain T, Therriault Hélène, Cantin André M, Payette Hélène, Wagner J Richard
Centre de Recherche sur le Vieillissement, Institut Universitaire de Gériatrie de Sherbrooke, PQ, Canada.
Am J Clin Nutr. 2003 Jan;77(1):189-95. doi: 10.1093/ajcn/77.1.189.
Ascorbate and glutathione play central roles in the defense against free radicals and oxidants that are implicated in chronic diseases.
The objective was to determine the ability of vitamin C supplements to modulate the concentration of glutathione in human lymphocytes.
The effect of vitamin C supplements was determined in a sequential study with time points before supplementation, after 13 wk of vitamin C supplements (500 or 1000 mg/d), and after 13 wk of matching placebo. The supplementation group was selected on the basis of low plasma ascorbate (<33 mmol/L) and consisted of 48 healthy men and women, smokers and nonsmokers, aged 25-64 y. Ascorbate and glutathione were measured in purified lymphocytes.
At baseline, the mean (+/-SD) concentration of plasma ascorbate was 19.5 +/- 7.2 micro mol/L, 22.5 micro mol/L below the median of normal distribution. The ascorbate concentration in plasma was linearly associated with that in lymphocytes (r = 0.53, P < 0.001). On supplementation with vitamin C, lymphocyte ascorbate increased by 51% (from 16.7 +/- 4.9 to 25.3 +/- 6.9 nmol/mg protein; P < 0.001) and was accompanied by an increase of lymphocyte glutathione by 18% (from 22.5 +/- 4.5 to 26.6 +/- 6.5 nmol/mg protein; P < 0.001). After placebo, the ascorbate and glutathione concentrations fell to near baseline concentrations (17.1 +/- 5.4 and 23.5 +/- 6.4 nmol/mg protein, respectively). No significant interaction was observed for sex and smoking status. Finally, the changes in lymphocyte ascorbate after supplementation were strongly associated with changes in lymphocyte glutathione (r = 0.71, P < 0.001). The association suggests that every 1-mol change in ascorbate is accompanied by a change of approximately 0.5 mol in glutathione.
Vitamin C supplements increase glutathione in human lymphocytes.
抗坏血酸和谷胱甘肽在抵御与慢性病相关的自由基和氧化剂方面发挥着核心作用。
确定维生素C补充剂调节人体淋巴细胞中谷胱甘肽浓度的能力。
在一项序贯研究中确定维生素C补充剂的效果，研究时间点包括补充前、补充13周维生素C（500或1000毫克/天）后以及服用13周匹配安慰剂后。补充组根据血浆抗坏血酸水平低（<33微摩尔/升）进行选择，由48名年龄在25 - 64岁的健康男女组成，包括吸烟者和非吸烟者。在纯化的淋巴细胞中测量抗坏血酸和谷胱甘肽。
基线时，血浆抗坏血酸的平均（±标准差）浓度为19.5±7.2微摩尔/升，比正态分布中位数低22.5微摩尔/升。血浆中抗坏血酸浓度与淋巴细胞中的抗坏血酸浓度呈线性相关（r = 0.53，P < 0.001）。补充维生素C后，淋巴细胞抗坏血酸增加了51%（从16.7±4.9增至25.3±6.9纳摩尔/毫克蛋白；P < 0.001），同时淋巴细胞谷胱甘肽增加了18%（从22.5±4.5增至26.6±6.5纳摩尔/毫克蛋白；P < 0.001）。服用安慰剂后，抗坏血酸和谷胱甘肽浓度降至接近基线浓度（分别为17.1±5.4和23.5±6.4纳摩尔/毫克蛋白）。未观察到性别和吸烟状况的显著交互作用。最后，补充后淋巴细胞抗坏血酸的变化与淋巴细胞谷胱甘肽的变化密切相关（r = 0.71，P < 0.001）。这种关联表明，抗坏血酸每变化1摩尔，谷胱甘肽大约变化0.5摩尔。
维生素C补充剂可增加人体淋巴细胞中的谷胱甘肽。
