It has been shown in vitro that
glycine can protect renal tubules and hepatocytes from hypoxic injury.
Glycine also attenuates ischemic injury in transplanted livers. The present study investigated the effect of enteral
glycine in a murine model of
ischemia/reperfusion injury of the small intestine. Mice (n = 12 in each group) were randomized to receive two gastric gavages of either a 20%
glycine (Gly) or 23% balanced
amino acid (AA)
solution with a 6-hour interval between each gavage. One hour after the second gavage, mice underwent superior mesenteric artery clamping for 20 minutes. The clamp was then released for reperfusion. Another group of mice (n = 8) underwent a
sham operation and served as additional control animals. Six hours after
ischemia/reperfusion, the mice were killed in order to assess the intestinal injury (intestinal
protein content, mucosal
disaccharidase activity, and intestinal histologic findings) and the systemic consequences (bacterial translocation, serum
interleukin-6, and lung
myeloperoxidase activity). A second set of mice (n = 55) underwent identical gavages and
ischemia/reperfusion and they were followed for survival. Compared to AA, enteral
glycine administered prior to intestinal
ischemia/reperfusion injury significantly preserved mucosal indices and intestinal histology and decreased lung
myeloperoxidase activity. Survival was also significantly increased in animals receiving
glycine compared to AA control mice. These data suggest that enteral
glycine supplementation may be beneficial in attenuating intestinal
ischemia/reperfusion injury and its related systemic effects in this murine model.