Research
Glycine
31 peer-reviewed studies curated from PubMed and Semantic Scholar.
Studies
Sorted by quality and recency
The effect of glycine administration on the characteristics of physiological systems in human adults: A systematic review.
Systematic review of glycine administration on eleven physiological systems in adult humans. Glycine showed positive effects on the nervous system, improving psychiatric symptoms and sleep, though studies had small sample sizes and high risk of bias. Larger studies are needed to explore glycine's potential in preventing or reversing ageing.
Glycine by enteral route does not improve major clinical outcomes in severe COVID-19: a randomized clinical pilot trial.
Open label, controlled clinical trial of glycine supplementation in 56 inpatients with severe COVID-19 requiring mechanical ventilation. Glycine did not improve major clinical outcomes such as mortality or time on mechanical ventilation, but was associated with lower serum fibrinogen levels.
Treatment of peri-implant mucositis: Adjunctive effect of glycine powder air polishing to professional mechanical biofilm removal. 12 months randomized clinical study.
This randomized clinical study evaluated the adjunctive effect of glycine-powder air-polishing (GPAP) compared to full-mouth ultrasonic debridement (Fm-UD) in treating peri-implant mucositis. The study found no significant adjunctive effect of GPAP over Fm-UD alone in achieving disease resolution, despite improvements in clinical signs of peri-implant inflammation.
JGMS EDITOR’S CHOICE ARTICLES OF 2023: RISK AND RECOVERY OF FUNCTIONAL DECLINE AND FRAILTY
The symposium presents four articles, including a randomized clinical trial by Sekhar Rajagopal et al. on GlyNAC supplementation in older adults. The study found improvements in glutathione deficiency, oxidative stress, mitochondrial dysfunction, inflammation, physical function, and aging hallmarks.
Efficacy of pharmacological agents for the management of treatment-resistant schizophrenia: a network meta-analysis.
Network meta-analysis comparing pharmacological interventions for treatment-resistant schizophrenia. Augmentation of antipsychotics with escitalopram, glycine, and Yokukansan showed significant reduction in symptom severity compared to clozapine. Escitalopram appeared to be the most efficacious treatment.
Evaluation of glycine treatment for reducing alcohol craving and self-administration in individuals with alcohol use disorder: A human laboratory trial.
RCT evaluating glycine treatment for reducing alcohol craving and self-administration in individuals with alcohol use disorder. Glycine treatment raised serum glycine levels by 125%, but did not reduce alcohol intake or craving compared to placebo. The association between alcohol-induced craving and self-administration was abolished in the glycine-treated group.
The effect of enteral glycine on plasma glycine and muscle structure, size, and function in the critically ill: A randomized controlled trial.
RCT evaluating the effect of enteral glycine on plasma glycine levels and muscle structure in critically ill patients. Glycine supplementation increased plasma and muscle glycine concentrations and showed potential in attenuating muscle loss, though no effect on myofiber diameter was observed. Patients receiving glycine had shorter ICU and hospital stays.
Metabolic impact of dietary glycine supplementation in individuals with severe obesity.
Exploratory study of dietary glycine supplementation in 19 individuals with severe obesity. Glycine supplementation increased plasma glycine levels, enhanced urinary excretion of certain metabolites, reduced plasma triglycerides and aminotransferases, and improved the glutamate-serine-glycine index, suggesting potential benefits for metabolic health and MASLD.
Impact of Glycine Powder Air-Abrasive Debridement on Peri-Implant Mucositis: A Randomized Control Trial of Clinical, Microbial, and Immunological Changes.
RCT comparing glycine powder air-abrasive debridement to ultrasonic instrumentation in 30 subjects with peri-implant mucositis. Glycine therapy led to early and sustained changes in host-microbial interactions, with significant microbial shifts and decreased pro-inflammatory cytokines, although changes were sustained for a maximum of 3 months.
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.
RCT of GlyNAC supplementation in older adults for 16 weeks, showing improvements in glutathione deficiency, oxidative stress, mitochondrial dysfunction, inflammation, and physical function. GlyNAC was safe and well-tolerated, promoting health in aging humans.
Nutritional Modulation of Sleep Latency, Duration, and Efficiency: A Randomized, Repeated-Measures, Double-Blind Deception Study.
This randomized, repeated-measures, double-blind deception study tested a nutritional blend of tryptophan, glycine, magnesium, tart cherry powder, and l-theanine on sleep measures in 16 participants. The intervention reduced sleep onset latency, increased total sleep time and sleep efficiency, and reduced morning sleepiness, with metabolomic analysis suggesting involvement of key sleep-regulating metabolites.
Gut barrier and microbiota changes with glycine and branched-chain amino acid supplementation in chronic haemodialysis patients.
This multicentre randomized double-blind crossover study evaluated the impact of glycine and BCAA supplementation on gut barrier and microbiota in chronic haemodialysis patients. The study found no significant impact on serum cytokines, appetite mediators, intestinal permeability, endocannabinoids, or faecal IgA. Microbiota composition and diversity remained stable, but BCAA supplementation decreased the abundance of L. paracasei and B. dentium.
Effect of N-acetyl cysteine and glycine supplementation on growth performance, glutathione synthesis, and antioxidative ability of grass carp, Ctenopharyngodon idella.
An 8-week feeding trial evaluated the effect of N-acetyl cysteine (NAC) and glycine supplementation on growth performance, glutathione synthesis, and antioxidative ability of grass carp. NAC improved growth performance and glutathione levels, while NAC plus glycine enhanced glutathione synthesis and antioxidative ability.
HEGPOL: Randomized, placebo controlled, multicenter, double-blind clinical trial to investigate hepatoprotective effects of glycine in the postoperative phase of liver transplantation [ISRCTN69350312]
A randomized, placebo-controlled, multicenter, double-blind clinical trial to investigate the hepatoprotective effects of glycine in the postoperative phase of liver transplantation. The study assesses the effect of multiple intravenous doses of glycine on liver-related injury and graft and patient survival, as well as its effect on cyclosporine A-induced nephrotoxicity.
Glycine mitigates fertilizer requirements of agricultural crops: case study with cucumber as a high fertilizer demanding crop
The study investigated the effects of glycine application on cucumber plants as an alternative to chemical fertilization. Glycine treatments increased leaf area and plant economic life compared to control. Soil application of 500 mg glycine/plant improved leaf mineral concentration, plant economic life, and total yield, comparable to NPK fertilization. Foliar application of 500 ppm glycine was effective, while 1000 ppm caused adverse effects. The study suggests glycine can enhance plant nutrition and yield.
Safety of an alkalinizing buffer designed for inhaled medications in humans.
Two open-label safety studies evaluated the inhalation of an alkaline glycine buffer in 20 non-smoking adults, including healthy controls and subjects with stable obstructive airway disease. The inhalation was well-tolerated with no adverse effects on spirometric parameters or vital signs, and it successfully alkalinized the airway lining fluid.
Comparison of glucose/electrolyte and glucose/glycine/electrolyte oral rehydration solutions in hospitalized children with diarrhea in Costa Rica.
RCT comparing glycine-fortified oral rehydration solution (ORS) to standard WHO/ORS in infants and small children with noncholera diarrhea. No statistically significant difference was found in clinical outcomes or serum electrolyte composition.
Orphan receptor GPR158 serves as a metabotropic glycine receptor: mGlyR
The study identifies the orphan receptor GPR158 as a metabotropic glycine receptor (mGlyR), which mediates slow neuromodulatory effects of glycine. Glycine binds to GPR158, inhibiting the RGS7-Gβ5 signaling complex and regulating neuronal excitability in cortical neurons.
Glycine inhibits NINJ1 membrane clustering to suppress plasma membrane rupture in cell death
The study investigates glycine's role in inhibiting NINJ1 membrane clustering to prevent plasma membrane rupture during cell death. Glycine was found to preserve cellular integrity by preventing NINJ1 clustering, providing cytoprotection in pyroptosis, necrosis, and post-apoptosis lysis.
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.
A 36-week open-label clinical trial in older adults and young adults tested GlyNAC supplementation. GlyNAC improved oxidative stress, mitochondrial dysfunction, inflammation, insulin resistance, endothelial dysfunction, genomic damage, cognition, strength, and body composition in older adults over 24 weeks, with benefits declining after withdrawal.
Glycine-based treatment ameliorates NAFLD by modulating fatty acid oxidation, glutathione synthesis, and the gut microbiome
The study investigates the effects of a glycine- and leucine-based tripeptide on nonalcoholic fatty liver disease (NAFLD) in a mouse model. Administration of glycine or Gly-Gly-L-Leu improved symptoms by enhancing fatty acid oxidation, glutathione synthesis, and modulating the gut microbiome, suggesting potential therapeutic benefits for NAFLD.
Glycine: The Smallest Anti-Inflammatory Micronutrient
This narrative review discusses the anti-inflammatory effects of glycine, highlighting its ability to decrease pro-inflammatory cytokines and improve insulin response. The review emphasizes the importance of dietary glycine supplementation in preventing chronic inflammation.
Glycine Signaling in the Framework of Dopamine-Glutamate Interaction and Postsynaptic Density. Implications for Treatment-Resistant Schizophrenia
The paper reviews the role of glycine in dopamine-glutamate interactions and its implications for treatment-resistant schizophrenia. It discusses glycine-centered therapeutics, including sarcosine, glycine itself, D-Serine, and bitopertin, and their potential in psychosis therapy.
Glycine, serine and threonine metabolism confounds efficacy of complement-mediated killing
The study investigates the role of glycine in potentiating serum to eliminate serum-resistant Escherichia coli. Exogenous glycine was found to increase the formation of membrane attack complex on bacterial membranes, suggesting potential strategies for managing infections with serum-resistant bacteria.
mTORC1 amplifies the ATF4-dependent de novo serine-glycine pathway to supply glycine during TGF-β1–induced collagen biosynthesis
The study investigates how mTORC1 signaling amplifies the ATF4-dependent de novo serine-glycine pathway to supply glycine during TGF-β1–induced collagen biosynthesis in lung fibroblasts. It highlights the role of the mTORC1-ATF4 axis in enhancing glycine production to support collagen production, suggesting potential therapeutic targets for fibrosis.
Changes in plasma glycine, L-serine, and D-serine levels in patients with schizophrenia as their clinical symptoms improve: results from the Juntendo University Schizophrenia Projects (JUSP).
The study compared plasma glycine, L-serine, and D-serine levels between 89 patients with schizophrenia and 50 healthy controls. It found that D-serine levels and the D-/L-serine ratio significantly increased in schizophrenic patients from admission to discharge, correlating with improvements in positive symptoms.
Glycine supplementation mitigates lead-induced renal injury in mice
The study explored the protective effects of glycine against lead-induced renal injury in mice. Glycine supplementation reduced BUN and creatinine serum levels and decreased oxidative stress biomarkers in renal tissue. Histopathological changes caused by lead exposure were also inhibited by glycine treatment.
Glycine Metabolism and Its Alterations in Obesity and Metabolic Diseases
This narrative review synthesizes recent advances in glycine metabolism, highlighting its role in metabolic pathways and its potential benefits in obesity and related metabolic disorders. It discusses glycine deficiency in conditions like obesity, type 2 diabetes, and non-alcoholic fatty liver disease, and evaluates the benefits of glycine supplementation.
Pharmacological screening of glycine amino acid prodrug of acetaminophen
The study developed a glycine amino acid prodrug of acetaminophen to reduce hepatotoxicity. In Wistar rats, the prodrug showed gastroprotective and hepatoprotective effects, reducing gastric lesions and preventing the rise in liver enzymes. It also prevented the depletion of hepatic glutathione, although its therapeutic efficacy was lower than acetaminophen.
Glycine Receptor β Subunits Play a Critical Role in Potentiation of Glycine Responses by ICS-205,930
The study investigated the sensitivity of recombinant glycine receptors to ICS-205,930 in Xenopus laevis oocytes. It found that glycine receptor beta subunits play a critical role in the potentiation of glycine responses by ICS-205,930, revealing a new high-affinity potentiating site on glycine receptors.
Dietary glycine and renal denervation prevents cyclosporin A-induced hydroxyl radical production in rat kidney.
The study investigates the mechanism of radical production caused by Cyclosporin A (CsA) in rat kidneys. It finds that dietary glycine or renal denervation can prevent CsA-induced hydroxyl radical production and nephrotoxicity by blocking the increase in renal nerve activity and subsequent vasoconstriction and hypoxia-reoxygenation.