The Regulatory Role of Pancreatic Enzymes in the Maintenance of Small Intestinal Structure and Enterocyte Turnover with Special Reference to Alpha Amylase

The aim of this study was to elucidate the impact of porcine pancreatic enzymes (Creon^® pancrelipase) in comparison to microbial-derived alpha amylase (MD amylase) on the small intestine wall structure, mucosal glycogen accumulation, and enterocyte turnover. The impact of enzyme supplementation on the small intestine was explored in 18 pigs with surgically induced exocrine pancreatic insufficiency (EPI). Four healthy pigs served as the control group. EPI led to reduced villus length, crypt depth, and thickness of the mucosa and muscularis layers compared to those of healthy pigs. All these changes appeared to be reversible after enzyme supplementation. Brush border thickness was decreased in EPI and increased with both enzyme preparations, with MD amylase treatment leading to the highest values in the proximal jejunum. No EPI-induced changes were observed in the goblet cell (GC) population, but significant increases in GC number and area were observed following MD amylase treatment. Glycogen accumulation within the duodenal mucosa was significantly increased in EPI pigs. EPI was also shown to significantly increase apoptotic activity and decrease proliferative activity in comparison to healthy animals, while both enzyme preparations resulted in the complete recovery of both proliferative and apoptotic activity in all investigated intestinal segments. Creon^® influenced the morphology of the small intestine. However, supplementation of exogenous microbial amylase alone also affected gut morphology in a similar way to that of the complex host pancreatic enzymes offered orally. These data indicate that in addition to their role in digestion of nutrients in EPI, intraluminal pancreatic enzymes, especially amylase, contribute to gut health through maintenance of the intestinal wall architecture and physiological enterocyte turnover.