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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, OBJECTIVE, METHODS, RESULTS. Meshes: Adult, Ascorbic Acid, Ascorbic Acid Deficiency, Chromatography, High Pressure Liquid, Female, Glutathione, Humans, Lymphocytes, Male, Middle Aged.
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Does vitamin C augment lymphocyte glutathione in subjects with ascorbate deficiency? Context: 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.
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Vitamin C supplements increase glutathione in human lymphocytes. Final Decision: yes