Proteomic Profiles of Adipose and Liver Tissues from an Animal Model of Metabolic Syndrome Fed Purple Vegetables

Abstract

Metabolic Syndrome (MetS) is a complex disorder that predisposes an individual to Cardiovascular Diseases and type 2 Diabetes Mellitus. Proteomics and bioinformatics have proven to be an effective tool to study complex diseases and mechanisms of action of nutrients. We previously showed that substitution of the majority of carbohydrate in a high fat diet by purple potatoes (PP) or purple carrots (PC) improved insulin sensitivity and hypertension in an animal model of MetS (obese Zucker rats) compared to a control sucrose-rich diet. In the current study, we used TMT 10plex mass tag combined with LC-MS/MS technique to study proteomic modulation in the liver (n = 3 samples/diet) and adipose tissue (n = 3 samples/diet) of high fat diet-fed rats with or without substituting sucrose for purple vegetables, followed by functional enrichment analysis, in an attempt to elucidate potential molecular mechanisms responsible for the phenotypic changes seen with purple vegetable feeding. Protein folding, lipid metabolism and cholesterol efflux were identified as the main modulated biological themes in adipose tissue, whereas lipid metabolism, carbohydrate metabolism and oxidative stress were the main modulated themes in liver. We propose that enhanced protein folding, increased cholesterol efflux and higher free fatty acid (FFA) re-esterification are mechanisms by which PP and PC positively modulate MetS pathologies in adipose tissue, whereas, decreased de novo lipogenesis, oxidative stress and FFA uptake, are responsible for the beneficial effects in liver. In conclusion, we provide molecular evidence for the reported metabolic health benefits of purple carrots and potatoes and validate that these vegetables are good choices to replace other simple carbohydrate sources for better metabolic health.

Dietary intervention improves health metrics and life expectancy of the genetically obese DU6 (Titan) mouse

“…In particular, fat utilization (enrichment of proteins such as ACACA, IDH1, and ACOX1) as well as lipid biosynthesis (FASN, ACLY, and ACSL5,) were enhanced, which might explain increased plasma cholesterol and triglyceride levels in these mice ( Figure S3). Similar changes have been observed in the liver during MetS (Ayoub et al, 2018;Hsieh et al, 2016) and aging (Houtkooper et al, 2011). Interestingly, proteins involved in lipid metabolism were not obviously enriched when old Titan mice were compared to age-matched controls ( Figure 5D).…”

Pistachio Consumption Prevents and Improves Lipid Dysmetabolism by Reducing the Lipid Metabolizing Gene Expression in Diet-Induced Obese Mice

“…Our results represent the first experimental data showing the ability of pistachio consumption to modulate lipid gene expression. On the other hand, several bioactive plant components [6,57,60] as well as functional foods [60,61,62] are able to counteract hepatic steatosis by positively modulating the expression of genes linked to lipid metabolism.…”

Biomarkers of Nutrition and Health: New Tools for New Approaches

“…It has, for example, been examined as a tool to evaluate the effects of dietary regimens in cancer treatment [205]. An interesting example is the use of proteomics to support the beneficial effects of purple vegetables, carrots and potatoes on metabolic health [206]. The collection of information on proteins and peptides, their cellular locations and functions, along with their expression patterns in different tissues and cells, provides powerful material for defining hypotheses regarding potential biomarkers in serum/plasma, prior to validation with specific tests [207].…”