NUTRITIONAL REGULATION OF CELL AND ORGAN GROWTH, DIFFERENTIATION, AND DEVELOPMENT
Location: Children Nutrition Research Center (Houston, Tx)
Title: Glucagon-like peptide-2 increases small intestinal mass of calves
Submitted to: Joint Meeting of the ADSA, AMSA, ASAS and PSA
Publication Type: Abstract Only
Publication Acceptance Date: May 1, 2008
Publication Date: July 1, 2009
Citation: Taylor, C.C., Burrin, D.G., McLeod, K.R., Harmon, D.L. 2009. Glucagon-like peptide-2 increases small intestinal mass of calves [abstract]. Joint Meeting of the ADSA, AMSA, ASAS and PSA. Journal of Animal Science. 87:234 (E-Suppl. 2).
Glucagon-like peptide-2 (GLP-2) is a 33-amino acid hormone secreted from the gastrointestinal tract in response to luminal nutrients that potently increases small intestinal mass in non-ruminants. However, the effects of GLP-2 on small intestinal mass and morphology of ruminants is unknown. Eight Holstein calves were paired by age and randomly assigned to treatment: vehicle (0.5% BSA in saline; n= 4) or GLP-2 (50 ug/kg BW bovine GLP-2 in vehicle; n= 4). Treatments were administered by subcutaneous injection every 12 h for 10 d. Calves were fed a 50:50 (DM basis) mixture of alfalfa cubes and calf starter at 2.75% of BW in 2 daily meals. On d 11, 2 h after an intravenous injection of 10 mg/kg BW 5-bromo-2'-deoxyuridine (BrdU), calves were killed, gastrointestinal tissues weighed, and epithelial samples obtained from the rumen, omasum, abomasum, duodenum, jejunum, ileum, and colon. Samples were analyzed for villus height, crypt depth, and BrdU staining. Compared to vehicle, GLP-2 increased small intestinal mass by 24% (P=0.04). Intestinal length was unchanged, but intestinal thickness was increased (P=0.02) by GLP-2, particularly because of increased epithelial mass in the jejunum (P=0.008) and ileum (P=0.04). Treatment with GLP-2 increased villus height in the duodenum (P=0.03), jejunum (P=0.06), and ileum (P=0.09). In addition, GLP-2 increased crypt depth in the duodenum (P=0.06) and jejunum (P=0.02). Treatment with GLP-2 increased crypt cell proliferation as indicated by increased BrdU-labeling in the duodenum (P=0.02), jejunum (P=0.01), and ileum (P=0.05). These results demonstrate that GLP-2 induces similar increases in ruminant intestinal growth as observed in non-ruminants and could be an important mediator of small intestinal growth in response to luminal nutrients in ruminants.