Short-chain fatty acids increase proglucagon and ornithine decarboxylase messenger RNAs after intestinal resection in rats.
BACKGROUND
Intestinal adaptation is a complex physiological process that is not completely understood. Systemic administration of short-chain fatty acids (SCFAs) has been shown to facilitate adaptation to small bowel resection; however the mechanisms underlying this phenomena are unknown.


METHODS
Forty-six male Sprague-Dawley rats underwent an 80% jejunoileal resection and jugular catheterization. After surgery, rats were randomly assigned to receive standard total parenteral nutrition (TPN) or an isoenergetic, isonitrogenous TPN supplemented with SCFAs. On day 3 or 7 after surgery, ileal samples were removed for determination of mucosal wet weight, DNA, RNA, and protein concentrations. Total cellular RNA was extracted for use in Northern blot analysis to quantify proglucagon and ornithine decarboxylase messenger RNAs (mRNAs).


RESULTS
Total, mucosal, and submucosal weights were increased (p < .05) in the SCFA group both 3 and 7 days after surgery. Ileal DNA and RNA concentrations were increased (p < .05) in the SCFA group at both time points; however ileal protein concentration did not differ between groups until 7 days after resection. Levels of proglucagon and ornithine decarboxylase messenger RNAs were higher (p < .05) in the SCFA group at both time points.


CONCLUSIONS
The upregulation of proglucagon and ornithine decarboxylase gene expression may be the mechanism by which SCFAs facilitate intestinal adaptation.
Tappenden
K A
KA
Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Canada.
Thomson
A B
AB
Wild
G E
GE
McBurney
M I
MI
D000222:Adaptation, Physiological / Q000235:genetics / Q000502:physiology*; D000818:Animals; D001835:Body Weight / Q000502:physiology; D005232:Fatty Acids, Volatile / Q000008:administration & dosage*; D005786:Gene Expression Regulation / Q000235:genetics; D005934:Glucagon / Q000235:genetics* / Q000378:metabolism; D007082:Ileum / Q000378:metabolism* / Q000502:physiology; D007581:Jejunoileal Bypass; D008297:Male; D009955:Ornithine Decarboxylase / Q000235:genetics* / Q000378:metabolism; D010288:Parenteral Nutrition; D011184:Postoperative Period; D052336:Proglucagon; D011498:Protein Precursors / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
D005232:Fatty Acids, Volatile; D011498:Protein Precursors; D012333:RNA, Messenger; D052336:Proglucagon; D005934:Glucagon; D009955:Ornithine Decarboxylase