Off-campus UNL users: To download campus access dissertations, please use the following link to log into our proxy server with your NU ID and password. When you are done browsing please remember to return to this page and log out.
Non-UNL users: Please talk to your librarian about requesting this dissertation through interlibrary loan.
Effects of grain sorghum wax and oil on cholesterol levels, gut microbiota, and tissue metabolic fingerprints / profiles of a hamster model with diet-induced hypercholesterolemia
Grain sorghum (GS) lipid has shown its ability to positively modulate plasma, hepatic cholesterol and gut microbiota in a hamster model. Responsible lipid ingredients as well as their target and off-target effects on cellular metabolism have not yet been studied as a potential safe and efficacious source of nutraceuticals. In our study, crude GS lipid was fractionated into wax and oil; and male Syrian hamsters were fed either a control diet, an atherogenic (athero) diet, or an athero diet containing 5% GS wax or oil. The objective of this research was to determine the chemical composition of each fraction and to monitor changes in cholesterol profiles, gut microbiota, and metabolic pool of the liver and large intestine of hamsters in response to the diets. The phytosterol rich GS oil showed greater cholesterol lowering impact than did the policosanol rich wax fraction by reducing cholesterol levels and increasing fecal sterol excretion. The wax supplement only increased fecal sterol and bile acid excretion. The athero diet decreased the population of family Lactobacillaceae and genus Lactobacillus in the fecal microbiota. Although GS wax slightly increased the abundance of unclassified Lactobacillaceae, neither GS oil nor wax restored the number of Lactobacillaceae and Lactobacillus. Non-targeted metabolomics using direct infusion mass spectrometry followed by clustering analysis showed GS wax or oil supplement compensated metabolic changes in the large intestine induced by the athero diet, but not in the liver. Targeted profiling of metabolites related to central carbon metabolism showed that the athero diet tended to decrease glycolytic intermediate levels but increase tricarboxylic acid (TCA) cycle intermediates both in the liver and the large intestine. GS oil or wax supplement restored, in part, the glycolysis and TCA cycle intermediates back to the control level, with the oil and the wax having a greater impact on the liver metabolites and the large intestinal metabolites, respectively. Synergistic interplay of various compounds in GS lipids can be proposed based on different metabolic impacts of GS wax and oil, in combination with differences between complex GS lipids and fractionated GS lipids on their ability to modulate cholesterol and gut microbiota.
Lee, Bo Hyun, "Effects of grain sorghum wax and oil on cholesterol levels, gut microbiota, and tissue metabolic fingerprints / profiles of a hamster model with diet-induced hypercholesterolemia" (2013). ETD collection for University of Nebraska - Lincoln. AAI3547571.