Epidemiological studies indicate that the consumption of green tea polyphenols (GTP) may reduce the risk of coronary artery disease. To explore the underlying mechanisms of action at the molecular level, we examined the effects of GTP on the cardiac mRNA and protein levels of genes involved in insulin and lipid metabolism and inflammation. In rats fed a high-fructose diet, supplementation with GTP (200 mg/kg BW daily dissolved in distilled water) for 6 wk, reduced systemic blood glucose, plasma insulin, retinol-binding protein 4, soluble CD36, cholesterol, triglycerides, free fatty acids and LDL-C levels, as well as the pro-inflammatory cytokines, tumor necrosis factor-alpha (TNF-alpha) and IL-6. GTP did not affect food intake, bodyweight and heart weight. In the myocardium, GTP also increased the insulin receptor (Ir), insulin receptor substrate 1 and 2 (Irs1 and Irs2), phosphoinositide-3-kinase (Pi3k), v-akt murine thymoma viral oncogene homolog 1 (Akt1), glucose transporter 1 and 4 (Glut1 and Glut4) and glycogen synthase 1 (Gys1) expression but inhibited phosphatase and tensin homolog deleted on chromosome ten (Pten) expression and decreased glycogen synthase kinase 3beta (Gsk3beta) mRNA expression. The sterol regulatory element-binding protein-1c (Srebp1c) mRNA, microsomal triglyceride transfer protein (Mttp) mRNA and protein, Cd36 mRNA and cluster of differentiation 36 protein levels were decreased and peroxisome proliferator-activated receptor (Ppar)gamma mRNA levels were increased. GTP also decreased the inflammatory factors: Tnf, Il1b and Il6 mRNA levels, and enhanced the anti-inflammatory protein, zinc-finger protein, protein and mRNA expression. In summary, consumption of GTP ameliorated the detrimental effects of high-fructose diet on insulin signaling, lipid metabolism and inflammation in the cardiac muscle of rats.

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The aim of this study was to determine whether systemic elevation of tumor necrosis factor (TNF)-alpha induces intestinal-derived apolipoprotein B (apoB)48-containing very low-density lipoprotein (VLDL) production in hamsters after fat loading and whether TNF-alpha disturbs the related mRNA expression in inflammatory, insulin and lipoprotein signaling pathways in primary enterocytes. In vivo TNF-alpha and Triton-WR1339 infusion, Western blotting and reverse transcriptase-polymerase chain reaction were combined to explore the mechanisms underlying intestinal overproduction of apoB48-containing chylomicrons and VLDL(1) particles by TNF-alpha. TNF-alpha infusion increased intestinal production of chylomicron and VLDL(1)-apoB48 in postprandial (fat load) states. Following TNF-alpha-treatment in enterocytes, there was enhanced gene expression of Il1alpha and beta, Il6 and Tnf and decreased mRNA levels of components of the insulin signaling pathway including the insulin receptor (Ir), Ir substrate-1 and 2, PI3 k, and Akt, but increased phosphatase and tensin homolog deleted on chromosome ten (Pten) protein and mRNA expression. TNF-alpha also induced Cd36 and peroxisome proliferators-activated receptor (Ppar)gamma expression, as well as microsomal triglyceride transfer protein (Mtp) protein and mRNA, but suppressed the sterol regulatory element binding protein (Srebp)1c protein and mRNA level. Systemic elevation of TNF-alpha stimulates the postprandial overproduction of apoB48-containing chylomicrons and VLDL(1) particles by disturbing intestinal gene expression of the inflammatory, insulin and lipoprotein pathways. These findings provide mechanistic links among the inflammatory factor, TNF-alpha, intestinal inflammatory/insulin insensitivity and the overproduction of intestinal apoB48-containing lipoproteins.

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Objectives To evaluate the effects of feeding a Total Western Diet (TWD) based on NHANES data containing 0, 2, 5 or 10% raw potato starch on the microbiome, gene expression, and resistance to Citrobacter rodentium infection in mice. Methods 3–4 week old C57Bl/6 mice were fed the TWD for 6 weeks followed by 3 weeks of the TWD containing 0, 3, 5, or 10% raw potato starch (RPS). Mice were euthanized and tissues collected for analysis. In other experiments, after 3 weeks on the RPS containing diets, mice were infected with Citrobacter rodenitium (Cr), mice euthanized at day 12 post-infection and tissues collected for analysis. DNA isolated from cecal or fecal contents was used for sequencing of the V3-V4 hypervariable regions of the 16S rRNA gene. For gene expression analysis, RNA isolated from colon and cecal tissues was sequenced on an Illumina HiSeq 4000 using a 1 × 50 bp single end format. Results Feeding the RPS diets resulted in changes to the microbiome with α-diversity decreasing with increasing levels of dietary RPS (p < 0.05). PCA analysis showed four discreet groupings based on the RPS level that were significantly different by 0.5 Unifrac PERMANOVA analysis (p < 0.001). The relative abundance of various genera was altered by feeding increasing levels of RPS. The genus Lachnospiraceae NK4A136 group was markedly increased in a dose-dependent fashion. Differential expression of the genes was highest in the cecum but decreased substantially in the proximal colon and further so in the distal colon. The pattern of gene expression observed suggest that RPS primes the intestine for immune responses to bacteria, parasites and viruses. However, mice fed the 10% RPS diet and infected with Cr had increased colonization of the colon at day 12 post-infection that was not observed at lower levels of dietary RPS (p < 0.05). Mice had increased hyperplasia and colonic pathology in the 10% RPS group compared to mice receiving diet without added RPS. 16S sequencing of cecal contents showed RPS-dependent changes in both uninfected and infected mice. Conclusions Dietary RPS significantly altered the microbiome of mice in the context of a NHANES-based Western Diet. Mice fed diets containing 10% RPS had significant changes in cecal and colon gene expression, Cr colon colonization and infection-induced pathology. Funding Sources USDA ARS.

Mechanism(s) underlying long-lasting effects of human breast milk (HBM) on gut development and immune function have not been investigated. To differentiate between HBM and formula diet’s persistent effect on gene expression of a small intestine, piglets (n=15/group) were fed either HBM or dairy-based formula (FM) from postnatal day 2 to 21, followed by a soy free pig wean diet until day 51. Relative to HBM-fed, FM-fed had heavier small intestine (436±15.3 vs 362±45 g, p<0.05) but no change in the length. Transcriptome analysis revealed that the identified genes associated with cytokines (4↑, 9↓; i.e. CXCL8↓), Wnt (2↑, 9↓; CDHR2↓), gonadotropin releasing hormone receptor (1↑, 10↓; PRLR↓), EGF receptor (1↑, 7↓; CBL↓), cadherin (7↓; FRK↓) and endothelins (7↓; PRKG2↓) signaling were differentially expressed (2–5 fold) in ileum (IL) of FM-fed relative to HBM-fed. Moreover, the genes involved in biological processes such as cellular (84↑, 138↓; 2–12 fold), metabolic (71↑, 104↓; 2–17 fold), immune (14↑, 27↓; 2–10 fold) and developmental (16↑, 40↓ genes; 2–6.8 fold) were differentially expressed in IL of FM-fed relative to HBM-fed. Genes associated with T- (BRAF) and B-cell (BRAF, ITPR3 and FRK) activation were also decreased in IL of FM-fed relative to HBM-fed. NK, B and T-reg cells populations were reduced in mesenteric lymph nodes of FM-fed relative to HBM-fed. In summary, the data suggest a persistent effect of FM and HBM diets on small intestine and diet-driven changes in specific pathways of a small intestine. HBM may regulate these pathways to favor the gut development and immune function. However, FM may not harmonize it well and thereby delay the physiological process. Microbiome role is being evaluated to understand a specific mechanism.

TNFa, stimulates the overproduction of intestinal apolipoproteins. We evaluated whether a water extract of cinnamon (Cinnulin PF®) improved the dyslipidemia induced by TNFa in Triton WR‐1339 treated hamsters, and whether Cinnulin PF® inhibits the TNFa‐induced over secretion of apoB‐48 in hamster enterocytes. In vivo, acute oral intake of Cinnulin PF® (50 mg per kg BW), inhibited the postprandial overproduction of apoB‐48 lipoproteins and serum triglycerides. Ex vivo 35S labeling studies, demonstrated that CE (10 and 20 ?g/mL) inhibited the over secretion of apoB‐48 induced by TNFa treated enterocytes. To determine the effects on the mRNA levels for the related genes of lipoprotein metabolism in enterocytes, fresh isolated primary enterocytes of hamsters were pre‐treated with TNFa(10 ng per mL for 30min), then treated with and without Cinnulin PF® (10ug/mL) for 0.5, 2h and 4h. Quantitative real‐time PCR assays demonstrated that Cinnulin PF® improved the mRNA expression of IR, IRS1, IRS2, PI3K and Akt1and decreased the mRNA expression of MTP, PTEN, IL1a and b, IL6 and TNFa in TNFa treated enterocytes. In summary, our results suggest that a water extract of cinnamon reverses TNFa‐induced overproduction of intestinal apoB‐48 via regulating the gene expression of components of the insulin signaling, lipoprotein and inflammatory pathways. (Funded by USDA/ARS and Integrity Nutraceuticals).

Green tea has multiple benefits to human health. Epidemiologic studies demonstrate that the consumption of green tea polyphenols (GTP) reduces the risk of coronary artery disease and cardiac events. To explore the underlying mechanisms of action at a molecular level, we examined the effects of GTP on the expression of the cardiac genes involved in insulin, lipid and inflammatory signaling pathways, using quantitative real‐time PCR. Rats, fed a high fructose diet for four weeks to induce insulin resistance, were divided into two groups: the control group and GTP group (200 mg/kg body weight daily dissolved in distilled water for 6 weeks). There were no significant differences in average food intake and bodyweight gain between groups. GTP reduced serum blood glucose, cholesterol, triglycerides, free fatty acids and LDL‐C levels, compared with the controls. Supplementation with GTP also increased insulin receptor, IRS1, IRS2, PI3K, Akt1, GLUT1 and GLUT4 mRNA levels in the myocardium; increased cardiac CD36, PTEN, PPARg mRNA levels; but decreased the inflammatory factors: TNFa and IL1ß mRNA levels. In summary, our data demonstrate that green tea polyphenols improve glucose and lipid metabolism and regulate the cardiac gene expression related to insulin, lipid and inflammatory pathways in fructose‐fed insulin resistant rats. (Funded by USDA/ARS and Integrity Nutraceuticals).