There are also findings that glycine is protective against mercury and iron toxicity. The studies mention glycine relieving oxidative stress, but taken together, it is difficult so far to see a comprehensive scheme for glycine’s protective actions. These are tissue, rather than organism, studies.
Modulation of mercury-induced mitochondria-dependent apoptosis by glycine in hepatocytes. - PubMed - NCBI
“Glycine treatment suppressed these apoptotic events, signifying its protective role in Hg-induced hepatocyte apoptosis as referred by reduction of p38, JNK and ERK MAPK signaling pathways. Results suggest that glycine can modulate Hg-induced oxidative stress and apoptosis in hepatocytes probably because of its antioxidant activity and functioning via mitochondria-dependent pathways….”
Iron induces hepatocytes death via MAPK activation and mitochondria-dependent apoptotic pathway: beneficial role of glycine. - PubMed - NCBI
“…iron (FeSO₄) intoxication caused NF-κB activation as well as the phosphorylation of p38 and ERK MAPKs. Iron (FeSO₄) administration also disrupted Bcl-2/Bad protein balance, reduced mitochondrial membrane potential, released cytochrome c and induced the activation of caspases and cleavage of PARP protein….Glycine (10 mM) supplementation… reduced all the iron (FeSO₄) induced apoptotic indices.
Glycine stimulates protein synthesis and inhibits oxidative stress in pig small intestinal epithelial cells. - PubMed - NCBI
“...glycine inhibited (P < 0.05) activation of caspase 3 by 25% and attenuated… apoptosis by 38% in intestinal porcine epithelial cell line 1 cells through promotion of reduced glutathione synthesis and expression of glycine transporter 1 while reducing the activation of extracellular signal-regulated kinases, c-Jun amino-terminal kinases, and p38 protein in the mitogen-activated protein kinase signaling pathway.”
Thanks for the additional pointers.
I suspect glycine chelates heavy metals, as several amino acids have been shown to do in vivo. Will see if I can find something specific on chelation and post it here.