Gut microbiota drives colon cancer risk associated with diet: a comparative analysis of meat-based and pesco-vegetarian diets.

Background: Colorectal cancer (CRC) risk is strongly affected by dietary habits with red and processed meat increasing risk, and foods rich in dietary fibres considered protective. Dietary habits also shape gut microbiota, but the role of the combination between diet, the gut microbiota, and the metabolite profile on CRC risk is still missing an unequivocal characterisation.

Methods: To investigate how gut microbiota affects diet-associated CRC risk, we fed Apc-mutated PIRC rats and azoxymethane (AOM)-induced rats the following diets: a high-risk red/processed meat-based diet (MBD), a normalised risk diet (MBD with α-tocopherol, MBDT), a low-risk pesco-vegetarian diet (PVD), and control diet.

A dual model of normal vs isogenic Nrf2-depleted murine epithelial cells to explore oxidative stress involvement.

Cancer-derived cell lines are useful tools for studying cellular metabolism and xenobiotic toxicity, but they are not suitable for modeling the biological effects of food contaminants or natural biomolecules on healthy colonic epithelial cells in a normal genetic context. The toxicological properties of such compounds may rely on their oxidative properties. Therefore, it appears to be necessary to develop a dual-cell model in a normal genetic context that allows to define the importance of oxidative stress in the observed toxicity.

Effects of sodium nitrite reduction, removal or replacement on cured and cooked meat for microbiological growth, food safety, colon ecosystem, and colorectal carcinogenesis in Fischer 344 rats.

Epidemiological and experimental evidence indicated that processed meat consumption is associated with colorectal cancer risks. Several studies suggest the involvement of nitrite or nitrate additives via N-nitroso-compound formation (NOCs). Compared to the reference level (120 mg/kg of ham), sodium nitrite removal and reduction (90 mg/kg) similarly decreased preneoplastic lesions in F344 rats, but only reduction had an inhibitory effect on Listeria monocytogenes growth comparable to that obtained using the reference nitrite level and an effective lipid peroxidation control.

Soy Lecithin in High-Fat Diets Exerts Dual Effects on Adipose Tissue Versus Ileum.

Scope: Lipopolysaccharides and their transporters, LBP and sCD14, are involved in systemic inflammation following a high-fat diet. Natural emulsifiers such as soy lecithin, rich in soybean polar lipids (SPL), are often used by the food industry but little is known about effects of associating SPL with different oils.

Methods And Results: Thus, this study investigates the effects of 4 weeks feeding of palm (P) or rapeseed (R) oil-enriched diets with or without SPL in mice, on white adipose tissue (WAT) inflammation, on ileum permeability, and on microbiota composition.

Urinary Metabolome Analysis Reveals Potential Microbiota Alteration and Electrophilic Burden Induced by High Red Meat Diet: Results from the French NutriNet-Santé Cohort and an In Vivo Intervention Study in Rats.

Scope: High red and processed meat consumption is associated with several adverse outcomes such as colorectal cancer and overall global mortality. However, the underlying mechanisms remain debated and need to be elucidated.

Methods And Results: Urinary untargeted Liquid Chromatography-Mass Spectrometry (LC-MS) metabolomics data from 240 subjects from the French cohort NutriNet-Santé are analyzed.

Study of the colonic epithelial-mesenchymal dialogue through establishment of two activated or not mesenchymal cell lines: Activated and resting ones differentially modulate colonocytes in co-culture.

Continuous and rapid renewal of the colonic epithelium is crucial to resist the plethora of luminal deleterious agents. Subepithelial fibroblasts contribute to this turnover by regulating epithelial proliferation and differentiation. However, when intestinal homeostasis is disturbed, fibroblasts can acquire an activated phenotype and play a major role in the progression of intestinal pathologies.

A meal rich in palm oil or butter modifies the sphingolipid profile of postprandial triglyceride-rich lipoproteins from type 2 diabetic women.

Elevated concentrations of triglyceride-rich lipoproteins (TGRL) in the fasting and postprandial states are risk factors for cardiovascular events, especially in type 2 diabetes (T2D). T2D modifies the lipid composition of plasma and lipoproteins and some sphingolipids (SP) have been validated as potent predictive biomarkers of cardiovascular disease occurrence. The main objectives of the present study were to characterize the plasma SP profile in fasting T2D patients and to determine whether SP are modified in postprandial TGRL from these patients compared to fasting TGRL.

Impact of Rapeseed and Soy Lecithin on Postprandial Lipid Metabolism, Bile Acid Profile, and Gut Bacteria in Mice.

Scope: Synthetic emulsifiers have recently been shown to promote metabolic syndrome and considerably alter gut microbiota. Yet, data are lacking regarding the effects of natural emulsifiers, such as plant lecithins rich in essential α-linolenic acid (ALA), on gut and metabolic health.

Methods And Results: For 5 days, male Swiss mice are fed diets containing similar amounts of ALA and 0, 1, 3, or 10% rapeseed lecithin (RL) or 10% soy lecithin (SL).

Rapeseed Lecithin Increases Lymphatic Lipid Output and α-Linolenic Acid Bioavailability in Rats.

Background: Soybean lecithin, a plant-based emulsifier widely used in food, is capable of modulating postprandial lipid metabolism. With arising concerns of sustainability, alternative sources of vegetal lecithin are urgently needed, and their metabolic effects must be characterized.

Objectives: We evaluated the impact of increasing doses of rapeseed lecithin (RL), rich in essential α-linolenic acid (ALA), on postprandial lipid metabolism and ALA bioavailability in lymph-cannulated rats.

Postprandial Triglyceride-Rich Lipoproteins from Type 2 Diabetic Women Stimulate Platelet Activation Regardless of the Fat Source in the Meal.

Scope: The aim of this study is to examine whether postprandial (PP) triglyceride-rich lipoproteins (TGRL) secreted after a moderate fat intake would activate platelets differently according to their fatty acid (FA) composition.

Methods And Results: In a parallel single-blind randomized trial, 30 women with type 2 diabetes are assigned a breakfast containing 20 g lipids from butter versus hazelnut-cocoa spread (HCS) rich in palm oil. Blood samples are collected at fasting and 4 h PP.

Lipopolysaccharide-Binding Protein, Soluble CD14, and the Long-Term Risk of Alzheimer's Disease: A Nested Case-Control Pilot Study of Older Community Dwellers from the Three-City Cohort.

Background: Identifying the mechanisms involved in the pathogenesis of Alzheimer's disease (AD) remains crucially important. Chronic age-related low-grade inflammation is considered to be one such mechanism, although its causes are unclear. Lipopolysaccharide (LPS)-type endotoxins, a major component of the outer membrane of Gram-negative bacteria, are known as potent pro-inflammatory molecules.

Acute effects of milk polar lipids on intestinal tight junction expression: towards an impact of sphingomyelin through the regulation of IL-8 secretion?

Milk polar lipids (MPL) are specifically rich in milk sphingomyelin (MSM) which represents 24% of MPL. Beneficial effects of MPL or MSM have been reported on lipid metabolism, but information on gut physiology is scarce. Here we assessed whether MPL and MSM can impact tight junction expression.

Milk Polar Lipids in a High-Fat Diet Can Prevent Body Weight Gain: Modulated Abundance of Gut Bacteria in Relation with Fecal Loss of Specific Fatty Acids.

Scope: Enhanced adiposity and metabolic inflammation are major features of obesity associated with altered gut microbiota and intestinal barrier. How these metabolic outcomes can be impacted by milk polar lipids (MPL), naturally containing 25% of sphingomyelin, is investigated in mice fed a mixed high-fat (HF) diet .

Methods And Results: Male C57Bl/6 mice receive a HF-diet devoid of MPL (21% fat, mainly palm oil, in chow), or supplemented with 1.