Glycine (aminoacetic acid) is most important and simple, nonessential amino acid in humans, animals, and many mammals. Glycine is a precursor for several important compounds such as creatine, purines and glucose, and is involved in a wide range of metabolic pathways. Besides participating in synthesizing structural biomolecules, glycine serves as one of the predecessors of glutathione, one of the most important antioxidants in the human body, and also supplementation that is important in avoiding the development of chronic inflammation.
GlyNAC (combination of glycine and N-acetylcysteine)
Cellular increases in oxidative stress and decline in mitochondrial function are identified as key defects in aging. Defects linked to oxidative stress and impaired mitochondrial fuel oxidation, such as inflammation, insulin resistance, endothelial dysfunction, and aging hallmarks, are present in older humans and are associated with declining strength and cognition, as well as the development of sarcopenic obesity. Investigations on the origins of elevated oxidative stress and mitochondrial dysfunction in older humans led to the discovery that deficiencies of the antioxidant tripeptide glutathione (γ-Glutamylcysteinylglycine) and its precursor amino acids glycine and cysteine may be contributory. Supplementation with GlyNAC (combination of glycine and N-acetylcysteine as a cysteine precursor) was found to improve/correct cellular glycine, cysteine, and glutathione deficiencies; lower oxidative stress; and improve mitochondrial function, inflammation, insulin resistance, endothelial dysfunction, genotoxicity, and multiple aging hallmarks; and improve muscle strength, exercise capacity, cognition, and body composition. The mice that received GlyNAC lived 24% longer than those that did not receive GlyNAC.
Glycine is genetically associated with lower coronary heart disease risk and lower incidence of type 2 diabetes. Glycine improved the endothelium function in aged rats possibly by enhancing eNOS expression and reducing the role of superoxide anion and contractile prostanoids that increase the nitric oxide bioavailability.
Glycine serves as the acceptor for a methylation reaction catalyzed by glycine N-methyltransferase, which takes a methyl group from S-adenosyl-L-methionine and transfers it to glycine to form sarcosine (methylglycine) and S-adenosyl-L-homocysteine. Glycine N-methyltransferase prolongs life in flies when overexpressed.
Because glycine residues occupy 1/3 of amino acid residues in collagen protein, the supply of glycine may be a limiting factor for collagen synthesis and must be present in the diet in large amounts to satisfy the demands for collagen synthesis for prevention of osteoarthritis. An optimized form of glycine precursor glycinamide (2-aminoacetamide) increased collagen production much more effectively than glycine, especially synergistically in combination with ascorbic acid. Moreover, some 2-aminoacetamide derivatives have good anti-inflammatory activity. Among them, compound f15 showed the most prominent performance and blocked the excitation of nuclear factor κB (NF-кB) signaling pathway in a concentration-dependent manner. Furthermore, in-vivo experiment showed that f15 reduced arthritic index in adjuvant-induced arthritis rats and inhibited the production of TNF-α and IL-1β in serum.
Glycine improves sleep quality
Glycine at a dose of 3 g/day before bedtime subjectively improves sleep quality and reduces sleepiness and fatigue during the day in individuals with insomniac tendencies or restricted sleep time. Glycine administration before bedtime also decreases core body temperature in human subjects.
The glycine cleavage system
Glycine takes part in one-carbon metabolism as a methyl group provider through the glycine cleavage system. The glycine cleavage system is a multienzyme complex consisting of four individual components: glycine decarboxylase, amino methyltransferase, glycine cleavage system protein H, and dihydrolipoamide dehydrogenase. It has been revealed that glycine influenced stem cell pluripotency by controlling the synthesis of SAM (S-adenosylmethionine - a methyl donor in histone as well as DNA methylation), thus promoting H3K4me3 modification, and open euchromatin. This process is present in human and mouse pluripotent stem cells.
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- GlyNac More Anti-Aging Proof!
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