Expression of SGLT1 mRNA in Duodenum,Jejunum and Ileum of Weaning Piglets and the Effect of Cysteamine on It

To investigate the patterns of sodium-glucose co-transporter 1(SGLT1) expression in duodenum, jejunum and ileum of weaning piglets and the effects of cysteamine, and to explore its possible mechanism, newborn piglets were allocated to control and treatment groups. From 12 d of age(D12), piglets in control group were fed basal diet, while the treatment group received basal diet supplemented with 120 mg/kg cysteamine. Piglets were weaned at D35 in both groups. Six piglets from each group (n = 6) were slaughtered on D28(one week before weaning), D35(weaning), D38, D42 and D45(3, 7 and 10 d after weaning), respectively. Mucosal tissue was collected from three different segments of small intestine(duodenum, jejunum and ileum) and a semi-quantitative RT-PCR was applied to determine the abundances of SGLT1 mRNA. Results showed that the highest expression of SGLT1 mRNA was detected in ileum, followed by jejunum and duodenum. The patterns of age-related change in SGLT1 mRNA expression were distinct in different segments of small intestine. The abundance of SGLT1 mRNA in duodenum increased significantly at D45 (P 0.05), while in jejunum a significant down-regulation was observed at D42 and D45 (P 0.01). In contrast, ileal expression of SGLT1 mRNA kept stable throughout the experiment. Cysteamine significantly improved the expression of SGLT1 mRNA in duodenum and jejunum after weaning, but did not affect the SGLT1 mRNA expression in ileum. The results indicate that the expression of SGLT1 mRNA is spatio-temporal specific in small intestine of weaning piglets, and that cysteamine affects the expression of SGLT1 in a spatio-temporal specific manner.