Alanyl-glutamine-supplemented parenteral nutrition increases luminal mucus gel and decreases permeability in the rat small intestine.
BACKGROUND
Effect of supplemental alanyl-glutamine in standard TPN (S-TPN) on luminal mucus gel and small intestinal permeability was investigated.


METHODS
Thirty Sprague-Dawley rats were divided into group I (n = 10), receiving standard rat diet; group II (n = 10), receiving S-TPN; and group III (n = 10), receiving alanyl-glutamine-supplemented TPN for 1 week. After 1 week, fluorescein isothiocyanate (FITC)-dextran was injected into the small intestine of the rats, and they were killed. A small intestinal sample and portal blood were obtained for morphologic and functional analysis of mucus gel and intestinal permeability.


RESULTS
In group II, thickness and optical density of mucus gel per millimeter serosal length of intestine were significantly lower than group I (p<.001) and were significantly higher in group III than in group II (p<.001). The number of goblet cells in the villi and in the crypt of the small intestine was significantly lower in group II than in group I (p<.001) and was significantly higher in group III than in group II (p<.001), with the exception of the villi of jejunum. Villous and crypt surface area per millimeter serosal length of intestine was significantly lower in group II than in group I (p<.001) and was significantly higher in group III than in group II (p<.001). Small intestinal permeability to FITC-dextran was significantly higher in group II than in group I (p<.001) and was significantly lower in group III than in group II (p<.001). Glucosamine synthetase level was significantly higher in group III than in group I and ileum of group II (p<.001).


CONCLUSIONS
Alanyl-glutamine-supplemented TPN prevents a decrease in mucus gel and an increase in small intestinal permeability associated with S-TPN.
Khan
J
J
Department of Pediatric Surgery, Osaka University Medical School, Suita, Japan.
Iiboshi
Y
Y
Cui
L
L
Wasa
M
M
Sando
K
K
Takagi
Y
Y
Okada
A
A
D000818:Animals; D004151:Dipeptides / Q000494:pharmacology*; D016650:Fluorescein-5-isothiocyanate / Q000378:metabolism; D005456:Fluorescent Dyes / Q000378:metabolism; D007413:Intestinal Mucosa / Q000187:drug effects*; D007421:Intestine, Small / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D010289:Parenteral Nutrition, Total; D010539:Permeability / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley
D004151:Dipeptides; D005456:Fluorescent Dyes; D016650:Fluorescein-5-isothiocyanate; C054122:alanylglutamine