Effects of dietary fats on heart-liver lipid compositions

Alnaam, Yaser

Abstract

Accumulation of lipids in various organs causes many diseases such as obesity, cardiac disorder and dysfunction of the liver. The intake of fats from the diet influences the way that lipids are metabolised in the heart and liver. This provides an energy source and is a route for the production of hormones. However, excess fats may also cause abnormal metabolic pathways that lead to disease. Altered lipid metabolism is also observed because of heart failure. The aim of this project is to investigate the effect of high fat diets and heart failure on the lipid compositions of both heart and liver tissues.
Rats were maintained for nine weeks. At this point they underwent aortic constriction surgery (to mimic hypertrophied heart) or control surgery (Sham). Post-surgery animals were fed either a Western diet (WD; 45% kcal of lipids) or a high fat diet (HFD; 60% kcal of lipids). Subsequently, lipid accumulation and compositions of heart and liver tissues were investigated by histological lipid stains and nuclear magnetic resonance spectroscopy methods. Data were analysed by using principal component analysis (PCA).
Hematoxylin and eosin (H & E) and oil red O stain sections of the heart and liver tissue showed lipid accumulating, in the form of droplets, inside the cells in all animals. On initial inspection, NMR data showed little obvious difference between any of the animal groups. However, PCA was employed differences in the triglyceride (TG) and unsaturated lipids of animals fed WD and HFD were revealed. Surgery, however, appeared to have no effect on the organ’s lipid compositions.
In conclusion, small but potentially significant changes in lipid compositions of WD and HFD were found in heart and liver tissues. The results of this study also suggest that the lipid diet composition may not be directly involved to propagate cardiac diseases and toxicity in the liver, which may need further investigation. However, the TG and FA unsaturated group may give an insight to develop as a biomarker to understand the mechanism between dietary surplus fat intake and lipid profiles of heart and liver and their clinical applications.

Citation

Alnaam, Y. Effects of dietary fats on heart-liver lipid compositions. (Thesis). University of Hull. https://hull-repository.worktribe.com/output/4193330

• Thesis Type: Thesis
• Deposit Date: Feb 8, 2023
• Publicly Available Date: Feb 8, 2023
• Keywords: Chemistry
• Public URL: https://hull-repository.worktribe.com/output/4193330
• Award Date: 2018-03