Dietary saturated fat and monounsaturated fat have reversible effects on brain function and the secretion of pro-inflammatory cytokines in young women

Abstract

Background Previous literature suggests that a higher ratio of palmitic acid (PA)/oleic acid (OA) in the diet induces inflammation, which may result in deficient brain insulin signaling, and, secondarily, impaired physical activity, sleep efficiency, and cognitive functioning. Objective We hypothesized that lowering the typical dietary PA/OA would affect the activation of relevant brain networks during a working memory task and would also lower secretion of pro-inflammatory cytokines. Design In 12 female subjects participating in a randomized, cross-over trial comparing 3-week high PA diet (HPA) and low PA and a high OA diet (HOA), we evaluated functional magnetic resonance imaging (fMRI) using an N-back test of working memory, cytokine secretion by lipopolysaccharide(LPS)-stimulated peripheral blood mononuclear cells (PBMC), and plasma cytokine concentrations. Results Brain activation during the HPA diet compared to the HOA diet was increased in regions of the basal ganglia including the caudate and putamen (p<0.005). In addition, compared to the HOA diet, during the HPA diet, the plasma concentrations of IL-6 (p= 0.04) and IL-1β (p= 0.05) were higher, and there was a higher secretion of IL-18 (p=0.015) and a trend for higher IL-1β secretion (p=.066) from LPS-stimulated PBMCs. Conclusions The HPA diet resulted in increased brain activation in the basal ganglia compared to the HOA diet as well as increased secretion of pro-inflammatory cytokines. These data provide evidence that short-term (2 week) diet interventions impact brain network activation during a working memory task and that these effects are reversible since the order of the study diets was randomized. These data are consistent with the hypothesis that lowering the dietary PA content via substitution with OA also could affect cognition.

Feeding Angptl4−/− mice trans fat promotes foam cell formation in mesenteric lymph nodes without leading to ascites

“…In our studies in RAW264.7 macrophages, we found that palmitate treatment potently activated UPR and in-flammatory gene expression. By contrast, elaidate and, especially, oleate suppressed UPR and pro-inflammatory gene expression, which was most evident when baseline levels of UPR and inflammation were raised using DMS or triascin C. These observations are consistent with existing evidence indicating that saturated and cis-unsaturated FAs are prolipotoxic and anti-lipotoxic, respectively (50,(53)(54)(55). Studies have indicated that palmitate may induce ER stress by altering the ER-membrane composition.…”

<p>Saturated Fatty Acids in Obesity-Associated Inflammation</p>

“…53 In addition, Dumas et al reported that subjects on high palmitic acid diet exhibit elevated circulating levels of IL-6 and IL-1β than subjects on low palmitic acid/high oleic acid diet. 54 These studies suggest that increased level of SFAs may represent a key link between obesity and inflammation.…”

Dietary Inflammatory Index and Site-Specific Cancer Risk: A Systematic Review and Dose-Response Meta-Analysis

“…The World Cancer Research Fund International/American Institute for Cancer Research Continuous Update Project Reports on diet, nutrition, and physical activity reported that there is strong evidence that higher consumption of red and processed meat and alcoholic drinks increases the risk of colorectal cancer (CRC); on the other hand, higher intakes of dairy products, whole grains, and fiber-containing foods decrease the risk of CRC (1). The have proinflammatory properties (11)(12)(13), whereas some others, including soy products and phytochemicals, may have anti-inflammatory features (14,15). Previous investigations have indicated that the consumption of flavonoids, whole grains, and legumes was associated with serum concentrations of low-grade inflammatory biomarkers, such as TNFα, C-reactive protein (CRP), or cell adhesion molecules (16)(17)(18)(19).…”