A Western-Style Breakfast Induces a More Pro-Inflammatory Postprandial Response and Promotes Greater Macrophage Lipid Accumulation Compared to a Mediterranean-Style Breakfast in Obese and Normal-Weight Individuals

Background and objectives: Since postprandial lipid metabolism has emerged as a risk factor for cardiovascular disease, the quality of dietary fat may have a crucial role in atherogenesis and metabolic inflammation. In this study, we propose that the quality of dietary fats and the metabolic status of individuals modulate postprandial triglyceride-rich lipoprotein (TRL) composition and the response of macrophages to TRL. Methods: Randomized controlled crossover trial in the postprandial phase in 12 normal-weight adults and 12 adults with obesity. Each participant consumed both a Western-style (WB) and a Mediterranean-style (MB) breakfast in separate sessions, containing butter or olive oil as the fat source, respectively. Blood samples were collected at baseline (0 h), 2 h, and 4 h postprandially, and TRL were isolated and used to treat THP-1 macrophages. Results: The intake of the WB led to higher concentrations of inflammatory-related markers, particularly in individuals with obesity, and resulted in a higher content of saturated fatty acids and lower of monounsaturated fatty acids in TRL compared to the MB. Staining TRL-treated macrophages with Oil Red O revealed substantial lipid accumulation, which was more pronounced in cells cultured with 4 h TRL from individuals with obesity. This was also evidenced by upregulation of gene expression of lipoprotein uptake receptors following the consumption of the WB. Conclusions: Consumption of a WB led to a more pro-inflammatory postprandial profile and promoted greater lipid accumulation in macrophages, particularly in individuals with obesity, compared to a MB. These findings highlight the importance of fat quality in meals for cardiovascular risk management, especially in populations with obesity.