The Durk Pearson & Sandy Shaw®
Life Extension NewsTM
Volume 8 No.
1 • January 2005
Anti-Inflammatory, Antisepsis Effects of Glycine
In the context of the
article just above, we would like to mention the anti-inflammatory and antisepsis effects of the amino acid glycine. An interesting paper notes that glycine has been shown to protect against endotoxin shock in the rat by inhibiting TNF-alpha (tumor necrosis factor-alpha, a major inflammatory cytokine released in response to bacterial infection). In their paper, the authors studied the effects of glycine on lipopolysaccharide (LPS, a bacterial cell-wall constituent that activates the immune system, causing the release of inflammatory cytokines)-induced cell-surface-marker expression, phagocytosis, and cytokine production in purified monocytes from healthy human donors. Glycine decreased LPS-induced TNF-alpha production and increased IL-10 expression (IL-10 is an important anti-inflammatory cytokine) in a dose-dependent manner. In a whole blood assay, glycine also reduced TNF-alpha and, in addition, reduced IL-1beta (another major inflammatory cytokine) as well as increasing IL-10.
The authors conclude that “Our data indicate that GLY [glycine] has a potential to be used as an additional immunomodulatory tool in the early phase of sepsis and in different pathophysiological situations related to hypoxia and reperfusion.” This could be a significant medical advance, since sepsis is the fourth largest cause of death among Americans.
Another paper on glycine notes that “Glycine also inhibits the proliferation and migration of endothelial cells and smooth muscle cells, suggesting that glycine may be beneficial in inhibiting graft rejection, cardiovascular disease, and angiogenesis.” These effects occur via glycine’s reduction of the inflammatory immune response. This paper also reports that “In rats injected with PG-PS [a primary structural component of gram-positive bacterial cell walls that causes a rheumatoid arthritis condition in rats] intra-articularly, dietary glycine attentuates ankle swelling and decreases infiltration of inflammatory cells, edema, and synovial hyperplasia in the joint.” Hence, by modulating immune activation, glycine may be a useful therapeutic for some autoimmune diseases.
A third paper reports that administration of glycine one hour after cecal (part of the large intestine) ligation and puncture (a procedure producing highly deadly sepsis in the absence of treatment) decreased the mortality rate in male adult rats from 50% to 0% at 10 days after the procedure. These authors conclude that “… this amino acid appears to be a useful adjunct for maintaining cellular functions and preventing lethality from polymicrobial sepsis.”
The use of glycine for these purposes is, of course, experimental. It is not clear what the proper dose should be or what possible problems might be caused by excessive doses. There has been little study of glycine’s use as a therapeutic in humans, except as an antirejection agent in transplantation, and data on potential toxicity of chronic high-dose intake are limited.
- Spittler et al. Immunomodulatory effects of glycine on LPS-treated monocytes: reduced TNFalpha production and accelerated IL-10 expression. FASEB J 13:563-71 (1999).
- Zhong et al. L-Glycine: a novel anti-inflammatory, immunomodulatory, and cytoprotective agent. Curr Opin Clin Nutr Metabol Care 6:229-40 (2003).
- Yang et al. Glycine attenuates hepatocellular depression during early sepsis and reduces sepsis-induced mortality,” Crit Care Med 29:1201-6 (2001).