Effects of High-Fat Diet Induced Obesity and Fructooligosaccharide Supplementation on Cardiac Protein Expression

Abstract

The mechanism by which high fat-diet induced obesity affects cardiac protein expression is unclear, and the extent to which this is modulated by prebiotic treatment is not known. These outcomes were assessed in rats initially fed a high-fat diet, then the top 40% weight gain group were randomly allocated to control (CON), high-fat (HF) and HF supplemented with fructooligosaccharide (32 g; HF-FOS) treatments for 12 weeks (n = 10/group). At sacrifice, left ventricles were either frozen or preserved in formalin. Serum was stored for glucose and insulin measurements. Protein spectra was obtained using an Orbitrap analyzer, processed with Sequest and fold changes assessed with Scaffold Q +. Treatment effects for body weights, glucose and insulin were assessed using one-way ANOVA, and the differential protein expression was assessed by a Mann–Whitney U test. The Database for Annotation, Visualization and Integrated Discovery and the Kyoto Encyclopedia of Genes and Genomes identified pathways containing overrepresented proteins. Hematoxylin and eosin sections were graded for hypertrophy and also quantified; differences were identified using Chi-square analyses and Mann-Whitney U tests. HF diet fed rats were significantly (p < 0.05) heavier than CON, and 23 proteins involved in mitochondrial function and lipid metabolism were differentially expressed between HF and CON. Between HF-FOS and HF, 117 proteins involved in contractility, lipid and carbohydrate metabolism were differentially expressed. HF cardiomyocytes were significantly (p < 0.05) more hypertrophic than CON. We conclude that high-fat feeding and FOS are associated with subcellular deviations in cardiac metabolism and contractility, which may influence myocardial function and alter the risk of cardiovascular disease.

Elucidation of the changes occurring at the proteome level in ovaries of high‐fat diet‐induced obese rats

“…In obese rats fed with an HFD for more than 12 weeks, a decrease in FA synthesis associated proteins and an increase in proteins involved in betaoxidation were observed. 20 Thomassen et al demonstrated that female rats fed with an HFD for 3 months had three times the peroxisomal beta-oxidation activity compared to male rats tissues. 26 Similarly, in another study conducted with hearts of obese rats, an increase in beta-oxidation caused activation of peroxisomes with increases in peroxisome protein levels (Abcd3 and Hsd17b4).…”

“…Increased lipid intake can be toxic for many tissues. In obese rats fed with an HFD for more than 12 weeks, a decrease in FA synthesis associated proteins and an increase in proteins involved in beta‐oxidation were observed 20 . Thomassen et al demonstrated that female rats fed with an HFD for 3 months had three times the peroxisomal beta‐oxidation activity compared to male rats tissues 26 .…”

“…After an adaptation period of 1 week, the rats were randomly distributed into two groups: the HFD and the control. There were 10 rats in each group weighing approximately 170–180 g. The dietary regimen for HFD was adapted from Safaraz et al 20 The rats in the control group (CG) were fed with a low‐fat diet and the rats in the high‐fat diet group (HFDG) were fed with HFD (Table 1). Each group of animals was subjected to different experimental conditions for a total of 18 weeks.…”

Current Research on the Effects of Non-Digestible Carbohydrates on Metabolic Disease

“…Rats fed a 32% FOS diet for 12 weeks showed significantly increased hypertrophy of cardiomyocytes through subcellular changes in cardiac metabolism and contractility, which could affect myocardial function and alter the risk of CVD [79]. In humans, intake of barley or oat β-glucan at 3-5 g/day for 3-5 weeks improves blood lipid profile and reduces CVD risk factors such as body mass index, waist circumference, blood pressure, LDL, and triglyceride levels [80][81][82].…”

The Interplay between Cardiovascular Disease, Exercise, and the Gut Microbiome

“…Fructans are polymers of fructose linked by -2,1 bonds; inulin is characterized as having longer polymerized chains, whereas FOS possesses shorter polymerized chains [ 35 ]. Rats fed a HFD for 12 weeks showed increased cardiomyocyte hypertrophy compared to rats on a control diet; however, this hypertrophy was not reversed with supplementation of FOS alongside the HFD [ 113 ]. CVD is an accumulation of long-term lifestyle habits; it is possible that 12 weeks of FOS was not a long enough intervention to see significant changes in cardiomyocyte physiology.…”