Trial reportThe American journal of clinical nutrition2011
Deficient synthesis of glutathione underlies oxidative stress in aging and can be corrected by dietary cysteine and glycine supplementation.
Trial report in The American journal of clinical nutrition, 2011. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to trial NCT02324426 (Central Nervous System Uptake of Intranasal Glutathione in Parkinson's Disease), which is not on this map. Cited by 159 papers, 1 of them a synthesis that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Central Nervous System Uptake of Intranasal Glutathione in Parkinson's Disease
Who cites it
159 citing papers in PubMed, 1 synthesis or guideline pooled it, 322 citations in OpenAlex.
- The impact of cysteine on lifespan in three model organisms: A systematic review and meta-analysis.Aging cell · 2025Pooled it
- Multinutrient Supplementation in Children With ADHD Reduced Pro- and Anti-Inflammatory Immune Factors in the MADDY Randomized Controlled Trial.Journal of attention disorders · 2026Trial
- Supplementing Glycine and N-Acetylcysteine (GlyNAC) in Older Adults Improves Glutathione Deficiency, Oxidative Stress, Mitochondrial Dysfunction, Inflammation, Physical Function, and Aging Hallmarks: A Randomized Clinical Trial.The journals of gerontology. Series A, Biological sciences and medical sciences · 2023Trial
- Antioxidant Efficacy of a Standardized Red Orange (Nutrients · 2022Trial
- Comparative effects of acute-methionine loading on the plasma sulfur-amino acids in NAC-supplemented HIV+ patients and healthy controls.Amino acids · 2018Trial
- Effect of N-acetyl cysteine and glycine supplementation on growth performance, glutathione synthesis, and antioxidative ability of grass carp, Ctenopharyngodon idella.Fish physiology and biochemistry · 2017Trial
- A randomized, placebo-controlled pilot trial of N-acetylcysteine on oxidative stress and endothelial function in HIV-infected older adults receiving antiretroviral treatment.AIDS (London, England) · 2016Trial
- Effect of increasing glutathione with cysteine and glycine supplementation on mitochondrial fuel oxidation, insulin sensitivity, and body composition in older HIV-infected patients.The Journal of clinical endocrinology and metabolism · 2014Trial
- Ferroptosis-related stress during aging and its relevance to disease.GeroScience · 2026Review
- Article
- Glycine as a Metabolic Regulator of Reproductive Function in Livestock: From Gametes to Early Embryos.Animals : an open access journal from MDPI · 2026Review
- Targeted Supplementation and Nutritional Strategies for Healthy Aging: A Review of Physiological and Molecular Benefits.Current nutrition reports · 2026Review
- One-carbon metabolism and cardiovascular disease: Molecular mechanisms, genetic influences, and epigenetic regulation.Biochemistry and biophysics reports · 2026Review
- Glutathione in Our Diet and Its Role in the Body: From Disease Prevention to Anti-Aging.Nutrients · 2026Review
- Integrative Metabolomics of Targeted and Nontargeted Analyses in T2D Progression.Diabetes care · 2026Article
- Gram-negative bacterial outer membrane proteins and lipopolysaccharides key factors linking chicken coop environment and oxidative stress.Redox biology · 2026Review
- SRN-901, a Novel Longevity Drug, Extends Lifespan and Healthspan by Targeting Multiple Aging Pathways.Drug design, development and therapy · 2026Article
- Molecular signatures and machine learning driven stress biomarkers for rainbow trout aquaculture and climate adaptation.Scientific reports · 2025Article
- Effects of Replacing Fishmeal with Enzymatically Hydrolyzed Pork Bone Meal (EHPBM) on Growth, Antioxidant Capacity, and Nutritional Metabolism inAnimals : an open access journal from MDPI · 2025Article
- Effectiveness of the serum ratio of l-cysteine to glutathione for the prediction of cardiovascular events.Journal of clinical biochemistry and nutrition · 2025Article
99 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
7 authors at 1 institution in 1 country.
Funding
Abstract
backgroundAging is associated with oxidative stress, but underlying mechanisms remain poorly understood.
objectiveWe tested whether glutathione deficiency occurs because of diminished synthesis and contributes to oxidative stress in aging and whether stimulating glutathione synthesis with its precursors cysteine and glycine could alleviate oxidative stress.
designEight elderly and 8 younger subjects received stable-isotope infusions of [2H(2)]glycine, after which red blood cell (RBC) glutathione synthesis and concentrations, plasma oxidative stress, and markers of oxidant damage (eg, F(2)-isoprostanes) were measured. Elderly subjects were restudied after 2 wk of glutathione precursor supplementation.
resultsCompared with younger control subjects, elderly subjects had markedly lower RBC concentrations of glycine (486.7 ± 28.3 compared with 218.0 ± 23.7 μmol/L; P < 0.01), cysteine (26.2 ± 1.4 compared with 19.8 ± 1.3 μmol/L; P < 0.05), and glutathione (2.08 ± 0.12 compared with 1.12 ± 0.18 mmol/L RBCs; P < 0.05); lower glutathione fractional (83.14 ± 6.43% compared with 45.80 ± 5.69%/d; P < 0.01) and absolute (1.73 ± 0.16 compared with 0.55 ± 0.12 mmol/L RBCs per day; P < 0.01) synthesis rates; and higher plasma oxidative stress (304 ± 16 compared with 346 ± 20 Carratelli units; P < 0.05) and plasma F(2)-isoprostanes (97.7 ± 8.3 compared with 136.3 ± 11.3 pg/mL; P < 0.05). Precursor supplementation in elderly subjects led to a 94.6% higher glutathione concentration, a 78.8% higher fractional synthesis rate, a 230.9% higher absolute synthesis rate, and significantly lower plasma oxidative stress and F(2)-isoprostanes. No differences in these measures were observed between younger subjects and supplemented elderly subjects.
conclusionsGlutathione deficiency in elderly humans occurs because of a marked reduction in synthesis. Dietary supplementation with the glutathione precursors cysteine and glycine fully restores glutathione synthesis and concentrations and lowers levels of oxidative stress and oxidant damages. These findings suggest a practical and effective approach to decreasing oxidative stress in aging.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.