Dietary Milk Polar Lipids Modulate Gut Barrier Integrity and Lipid Metabolism in C57BL/6J Mice During Systemic Inflammation Induced by Escherichia Coli Lipopolysaccharide

The focus of this work is the role milk polar lipids play in affecting gut permeability, systemic inflammation, and lipid metabolism during acute and chronic inflammation induced by a single subcutaneous injection of lipopolysaccharide. Groups of C57BL/6J mice were fed 1 of 3 diets: a modified AIN-93G diet with a moderate level of fat (control; CO), CO with milk gangliosides (GG), and CO with milk polar lipids (MPL). The MPL diet did not prevent a gut permeability increase upon LPS stress but increased the expression of tight junction proteins zonula occludens-1 and occludin in the colon mucosa. The GG diet prevented the gut permeability increase upon LPS stress. The MPL diet decreased absolute and relative liver mass and decreased hepatic gene expression of acetyl-CoA carboxylase 2 and 3-hydroxy-3-methylglutaryl-CoA reductase. The GG diet increased hepatic gene expression of acetyl-CoA acyltransferase 2. Overall, milk GG protected the intestinal barrier integrity but had little effect on systemic inflammation and lipid metabolism; conversely, milk MPL had complex effects on gut permeability, did not affect systemic inflammation, and had a beneficial effect on hepatic lipid metabolism.