Effect of Dietary Fat Restriction on Vascular Function Inaugural-Dissertation

Overweight and obesity are chronic diseases, which are increasingly affecting children and adolescents, and if not treated immediately then fat children from today will become patients from tomorrow. The objective of this study was to investigate whether dietary fat restriction normalizes body weight, impaired glucose tolerance and endothelium-dependent contractions induced by high dietary fat intake in young rodents. C57BL/6J mice, 4 weeks of age, were divided into Control group, which was fed with standard rodent chow (12% of fat); High-Fat group, which was fed for 30 weeks with the high-fat (HF) diet (41% fat) and Fat Restriction group, which was fed for 15 weeks with the HF diet (41% of fat), followed by standard chow (12% of fat) for 15 weeks. Body weight was monitored and glucose tolerance test was performed. Vascular responses to acetylcholine were investigated in aortic and carotid artery rings ex vivo in the absence or presence of nitric oxide and prostanoids. Body weight was increased in the High-Fat group and was normalized in the Fat Restriction group to similar levels as in the Control group. Impaired glucose tolerance detected in HighFat group was normalized in the Fat Restriction group. In the High-Fat group, endotheliumdependent contractions were increased in aorta and carotid arteries, and these contractions were attenuated in the Fat Restriction group to the same level as in the Control group. Moreover, the extent and sensitivity of these contractions varied between aorta and carotid arteries in the presence or absence of nitric oxide. In conclusion, intake of high amounts of fat leads to weight gain, glucose intolerance and enhanced endothelium-dependent contractile responses in aorta and carotid artery of young mice. All these effects were normalized after dietary fat restriction. These findings thus suggest that long term reduction in intake of dietary fat improves the metabolic and vascular function in young mice. Posted at the Zurich Open Repository and Archive, University of Zurich ZORA URL: https://doi.org/10.5167/uzh-68243 Originally published at: Baltensperger-Schneider, Heidi Lea. Effect of dietary fat restriction on vascular function. 2010, University of Zurich, Faculty of Medicine. Universitätsspital Zürich Arbeit unter der Leitung von: Dr. rer. nat. I. Bhattacharya Dr. rer. nat. E. Haas (ab Februar 2009) Prof. Dr. med. M. Barton (bis Januar 2009) Effect of Dietary Fat Restriction on Vascular Function Inaugural-Dissertation Zur Erlangung der Doktorwürde der medizinischen Fakultät Der Universität Zürich vorgelegt von Heidi Lea Baltensperger-Schneider