Lipid-Rich Enteral Nutrition Reduces Postoperative Ileus in Rats via Activation of Cholecystokinin-Receptors

Objective: This study investigates the effect of lipid-rich nutrition on the local inflammatory response and gastrointestinal hypomotility in a rat model of postoperative ileus. Background: Postoperative ileus is a major clinical problem, in which inflammation of the intestinal muscularis plays a key pathogenic event. Previously. administration of lipid-rich nutrition has been shown to reduce inflammation by activation of the autonomic nervous system via cholecystokinin-receptors. Methods: Postoperative ileus was induced by manipulation of the small intestine in rats. Peritoneal lavage fluid, plasma, and jejunal segments were collected at several time points to determine inflammatory mediators in fasted rats and rats fed a lipid-rich or control nutrition. Gastrointestinal transit was measured 24 hours after Surgery. Results: Administration of lipid-rich nutrition markedly reduced the manipulation-induced local inflammatory response compared to rats treated with control nutrition. The intervention with lipid-rich nutrition significantly reduced plasma levels of rat mast cell protease-II (P < 0.05) and peritoneal levels of tumor necrosis factor-alpha (P < 0.01) and interleukin-6 (P < 0.05). Furthermore, the influx of neutrophils, expressed as tissue level myeloperoxidase was significantly prevented by lipid-rich nutrition (P < 0.05). Above all administration of lipid-rich enteral nutrition resulted in a significant improvement of gastrointestinal transit compared to control nutrition (P < 0.05). Blocking of cholecystokinin-receptors prevented the anti-inflammatory and motility promoting effect of lipid-rich feeding. Conclusion: Our data demonstrate that nutritional stimulation of the autonomic nervous system with enteral lipids reduces postoperative ileus by inhibition of inflammation. Clinically, lipid-rich enteral nutrition may be a new therapeutic option in the treatment of postoperative ileus.