Tier 4 — mechanistic

Effect of increasing glutathione with cysteine and glycine supplementation on mitochondrial fuel oxidation, insulin sensitivity, and body composition in older HIV-infected patients

Nguyen D, Hsu JW, Jahoor F, Sekhar RV
The Journal of clinical endocrinology and metabolism 2014 99(1):169-177

Bibliography

PubMed
PMID 24081740
PubMed Central
PMC3879663
DOI
10.1210/jc.2013-2376
Funding
Support from the Baylor-UT Council for AIDS Research (NIH AI036211), Baylor Alkek Bridge fund, Baylor General Clinical Research Center (NIH RR-0188) and Baylor NIH Diabetes Research Center (P30DK079638).
Competing interests
The authors declared no conflicts of interest. The disclosure also identifies R. V. Sekhar as an inventor on US20110077303, with rights held by Baylor College of Medicine.

Study snapshot

DesignExploratory human intervention
ModelAdult humans
Sample8 older glutathione-deficient men living with HIV
InterventionGlycine 1.33 mmol/kg/day plus cysteine 0.81 mmol/kg/day supplied as NAC; no concurrent placebo group
Duration14 days
EndpointsGlutathione synthesis; Tracer-measured fuel oxidation; Clamp insulin sensitivity; Body composition and strength

What the study showed, in plain terms

This mechanistic HIV pilot associated precursor-driven glutathione restoration with changes in fuel oxidation and insulin sensitivity. It is an early combination study with a narrow clinical population.

Key findings

  • Glutathione synthesis and availability improved.
  • Selected metabolic, strength and body-composition measures also changed.

What this study can and cannot tell us

Eight men and an uncontrolled pre-post design limit causal conclusions.

The findings cannot be assumed to apply to glycine alone or healthy adults.

Related papers in the corpus

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A Randomized Controlled Clinical Trial in Healthy Older Adults to Determine Efficacy of Glycine and N-Acetylcysteine Supplementation on Glutathione Redox Status and Oxidative Damage
Lizzo G et al. · Frontiers in aging · 2022
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Glycine and N-acetylcysteine (GlyNAC) supplementation in older adults improves glutathione deficiency, oxidative stress, mitochondrial dysfunction, inflammation, insulin resistance, endothelial dysfunction, genotoxicity, muscle strength, and cognition: Results of a pilot clinical trial
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Tier 4
Supplementing Glycine and N-acetylcysteine (GlyNAC) in Aging HIV Patients Improves Oxidative Stress, Mitochondrial Dysfunction, Inflammation, Endothelial Dysfunction, Insulin Resistance, Genotoxicity, Strength, and Cognition: Results of an Open-Label Clinical Trial
Kumar P et al. · Biomedicines · 2020
Tier 4
Deficient synthesis of glutathione underlies oxidative stress in aging and can be corrected by dietary cysteine and glycine supplementation
Sekhar RV et al. · The American journal of clinical nutrition · 2011
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Glutathione synthesis is diminished in patients with uncontrolled diabetes and restored by dietary supplementation with cysteine and glycine
Sekhar RV et al. · Diabetes care · 2011

Editorial review

Reviewed by the Biohack Blueprint research team

Last verified

Dr. Khaled Mahmoud, MBBChCritical Care Medicine, Longevity Science & Editorial Direction