Intrauterine growth restriction (IUGR) results in abnormal morphology and gastrointestinal function, such as reduced villi height and crypt depth, thinner mucosa and muscle layers, and reduced brush border enzyme activities, delayed gastric emptying, increased stress response. As a gastrointestinal growth factor, the manner by which the porcine glucagon-like peptide-2 (pGLP-2) microsphere administration restored the gastrointestinal function and growth performance of IUGR piglets was investigated. Fourteen newborn Duroc × (Yorkshire × Landrace) IUGR piglets (0.92 ± 0.113 kg) were assigned into the IUGR (negative control group) and pGLP-2 microsphere groups. The piglets in group pGLP-2 were intraperitoneally administered with 100 mg pGLP-2 microspheres on day 1 after birth. From days 15 to 26 of trial, the body weight of the pGLP-2 group was significantly higher than that of the control. IUGR piglets of group pGLP-2 showed a significantly increased pancreas weight, serum insulin content and activity of lipase and amylase. Injection of pGLP-2 microspheres restored the intestinal absorptive capacity by significantly increasing the mRNA expression of the sodium-glucose cotransporter 1 in the jejunum and the peptide transporter 1 in the jejunum. It also restored the redox balance by increasing the catalase mRNA expression and decreasing the heat shock protein 70 mRNA expression. In addition, this improvement was associated with the significant increase in gut diameter, length and weight. Therefore, it was concluded that the injection of pGLP-2 microspheres was a suitable therapeutic strategy for compensatory growth in low birth weight IUGR piglets.
Keywords: Compensatory growth; digestive enzymes; gene expression; glucagon-like peptide-2; hormone secretion; intrauterine growth retardation; morphology; piglets.