Project description:We previously reported that lifetime consumption of soy proteins or whey proteins reduced the incidence of azoxymethane (AOM)-induced colon tumors in rats. To obtain insights into these effects, global gene expression profiles of colons from rats with lifetime ingestion of casein (CAS, control diet), soy protein isolate (SPI), and whey protein hydrolysate (WPH) diets were determined. We identified 31 induced and 49 repressed genes in the proximal colons of the SPI-fed group and 44 induced and 119 repressed genes in the proximal colons of the WPH-fed group, relative to CAS. Hierarchical clustering identified the co-induction or co-repression of multiple genes by SPI and WPH. The differential expression of I-FABP (2.92-, 3.97-fold down-regulated in SPI and WPH fed rats; P = 0.023, P = 0.01, respectively), cyclin D1 (1.61-, 2.42-fold down-regulated in SPI and WPH fed rats; P = 0.033, P = 0.001, respectively), and the c-neu proto-oncogene (2.46-, 4.10-fold down-regulated in SPI and WPH fed rats; P < 0.001, P < 0.001, respectively) mRNAs were confirmed by real-time quantitative RT-PCR. SPI and WPH affected colonic neuro-endocrine gene expression: peptide YY (PYY) and glucagon mRNAs were down-regulated in WPH fed rats, whereas somatostatin mRNA and corresponding circulating protein levels, were enhanced by SPI and WPH. The identification of transcripts co- or differentially-regulated by SPI and WPH diets suggests common as well as unique anti-tumorigenesis mechanisms of action which may involve growth factor, neuroendocrine and immune system genes. SPI and WPH induction of somatostatin, a known anti-proliferative agent for colon cancer cells, would inhibit tumorigenesis Experiment Overall Design: Male Sprague Dawley rats, fed one of the three purified diets, were studied at 40 weeks after AOM injection and when tumors had developed in some animals of each group. Total RNA, purified from non-tumor tissue within the proximal half of each colon, was used to prepare biotinylated probes, which were hybridized to Affymetrix RG_U34A rat microarrays.
Project description:We previously reported that lifetime consumption of soy proteins or whey proteins reduced the incidence of azoxymethane (AOM)-induced colon tumors in rats. To obtain insights into these effects, global gene expression profiles of colons from rats with lifetime ingestion of casein (CAS, control diet), soy protein isolate (SPI), and whey protein hydrolysate (WPH) diets were determined. We identified 31 induced and 49 repressed genes in the proximal colons of the SPI-fed group and 44 induced and 119 repressed genes in the proximal colons of the WPH-fed group, relative to CAS. Hierarchical clustering identified the co-induction or co-repression of multiple genes by SPI and WPH. The differential expression of I-FABP (2.92-, 3.97-fold down-regulated in SPI and WPH fed rats; P = 0.023, P = 0.01, respectively), cyclin D1 (1.61-, 2.42-fold down-regulated in SPI and WPH fed rats; P = 0.033, P = 0.001, respectively), and the c-neu proto-oncogene (2.46-, 4.10-fold down-regulated in SPI and WPH fed rats; P < 0.001, P < 0.001, respectively) mRNAs were confirmed by real-time quantitative RT-PCR. SPI and WPH affected colonic neuro-endocrine gene expression: peptide YY (PYY) and glucagon mRNAs were down-regulated in WPH fed rats, whereas somatostatin mRNA and corresponding circulating protein levels, were enhanced by SPI and WPH. The identification of transcripts co- or differentially-regulated by SPI and WPH diets suggests common as well as unique anti-tumorigenesis mechanisms of action which may involve growth factor, neuroendocrine and immune system genes. SPI and WPH induction of somatostatin, a known anti-proliferative agent for colon cancer cells, would inhibit tumorigenesis Keywords: Comarative genomic hybridization
Project description:Epidemiologic studies demonstrate that women from cultures that consume high levels of dietary soy have reduced breast cancer rates compared to women from cultures where soy consumption is typically much lower. The types of soy products consumed can also differ with Asian cultures consuming primarily minimally refined soy products while Western cultures often consume more highly refined soy products such as isolated soy protein (ISP). Our previous work showed that lifetime exposure to a diet containing 20% ISP promoted mammary tumor development in MTB-IGFIR transgenic mice. In this study, lifetime exposure to lower levels of ISP were evaluated (5% ISP and 1% ISP) to determine whether more moderate levels of ISP could protect against mammary tumorigenesis. A standard rodent diet, Teklad 2018 was also included in this study and Teklad 2018 contains a less refined form of soy, namely soybean meal. MTB-IGFIR mice fed ISP diets, independent of the concentration, displayed increased mammary tumor incidence and reduced tumor latency compared to MTB-IGFIR mice fed a 20% casein diet. Unexpectedly, MTB-IGFIR mice fed Teklad 2018 were completely protected against mammary tumor development. Although RNA sequencing of mammary tumors from ISP or casein fed mice did not identified gene expression patterns associated with the ISP diets, the ISP diets consistently promoted the expression of contractile related proteins in pubertal mammary glands. Therefore, lifetime exposure to ISP may alter gene expression in pubertal mammary glands rendering them more susceptible to transformation. Based on these findings women may want to avoid highly refined soy products such as ISP and switch to less refined forms of dietary soy until additional studies can be performed.
Project description:Epidemiologic studies demonstrate that women from cultures that consume high levels of dietary soy have reduced breast cancer rates compared to women from cultures where soy consumption is typically much lower. The types of soy products consumed can also differ with Asian cultures consuming primarily minimally refined soy products while Western cultures often consume more highly refined soy products such as isolated soy protein (ISP). Our previous work showed that lifetime exposure to a diet containing 20% ISP promoted mammary tumor development in MTB-IGFIR transgenic mice. In this study, lifetime exposure to lower levels of ISP were evaluated (5% ISP and 1% ISP) to determine whether more moderate levels of ISP could protect against mammary tumorigenesis. A standard rodent diet, Teklad 2018 was also included in this study and Teklad 2018 contains a less refined form of soy, namely soybean meal. MTB-IGFIR mice fed ISP diets, independent of the concentration, displayed increased mammary tumor incidence and reduced tumor latency compared to MTB-IGFIR mice fed a 20% casein diet. Unexpectedly, MTB-IGFIR mice fed Teklad 2018 were completely protected against mammary tumor development. Although RNA sequencing of mammary tumors from ISP or casein fed mice did not identified gene expression patterns associated with the ISP diets, the ISP diets consistently promoted the expression of contractile related proteins in pubertal mammary glands. Therefore, lifetime exposure to ISP may alter gene expression in pubertal mammary glands rendering them more susceptible to transformation. Based on these findings women may want to avoid highly refined soy products such as ISP and switch to less refined forms of dietary soy until additional studies can be performed.
Project description:To increase our knowledge of the effects of Fructo oligosaccharides (FOS) on Salmonella infection in fats, a controlle rat infection study was performed. Two groups of 12 rats were adapted for 14 days to a cellulose diet and one group of 12 rats to a FOS diet. One cellulose-fed group and the FOS-fed group were infected with Salmonella. Two days post infection mRNA was collected from the mucosa of the colon and changes in gene expression were assessed using an Agilent rat whole genome microarray (G4131A Agilent Technologies). Results indicate that Salmonella affects colonic mucosal gene expression, which is further enhanded by dietary FOS. Keywords: Dietary infection study, colon mucosa, Rat
Project description:The human gut microbiota is crucial for degrading dietary fibres from the diet. However, some of these bacteria can also degrade host glycans, such as mucins, the main component of the protective gut mucus layer. Specific microbiota species and mucin degradation patterns are associated with inflammatory processes in the colon. Yet, it remains unclear how the utilization of mucin glycans affects the degradation of dietary fibres by the human microbiota. Here, we used three dietary fibres (apple pectin, β-glucan and xylan) to study in vitro the dynamics of colon mucin and dietary fibre degradation by the human faecal microbiota. The dietary fibres showed clearly distinguishing modulatory effects on faecal microbiota composition. The utilization of colon mucin in cultures led to alterations in microbiota composition and metabolites. Metaproteome analysis showed the central role of the Bacteroides in degradation of complex fibres while Akkermansia muciniphila was the main degrader of colonic mucin. This work demonstrates the intricacy of complex glycan metabolism by the gut microbiota and how the utilization of host glycans leads to alterations in the metabolism of dietary fibres. Metaproteomics analysis of this data reveals the functional activities of the bacteria in consortia, by this contributing to a better understanding of the complex metabolic pathways within the human microbiota that can be manipulated to maximise beneficial microbiota-host interactions. In this study two different mucin samples were used: commercial porcine gastric mucin and in house prepared porcine colonic mucin. This dataset analyses the proteome of: A) autoclaved porcine colonic mucin; B) not autoclaved porcine colonic mucin; C) porcine gastric mucin.
Project description:The role of diet in the prevention of breast cancer is widely accepted, yet little is known on how early dietary effects mitigate adult cancer risk. Soy consumption is associated with reduced breast cancer risk in women, an effect largely attributed to the soy isoflavone genistein (GEN). We previously showed lower chemically-induced mammary tumor incidence in young adult rats with lifetime dietary intake of soy protein isolate (SPI), a highly refined soy product in infant formula, than in those fed the control diet Casein (CAS). To gain insight into signaling pathways underlying dietary tumor protection, we performed genome-wide expression profiling of mammary epithelial cells from young adult rats lifetime fed CAS, SPI, or supplemental GEN-based diets. We identified mammary epithelial genes regulated by SPI (79 total) and GEN (99 total) using Affymetrix rat 230A GeneChip arrays and found minimal overlap in gene expression patterns. We showed that the regulated transcripts functionally cluster in biochemical pathways involving metabolism, immune response, signal transduction, and ion transport. We confirmed the differential expression of Wnt (Wnt5a, Sfrp2) and Notch (Notch2, Hes1) signaling components by SPI and/or GEN using QPCR. Wnt pathway inhibition by GEN was supported by lower Cyclin D1 immunoreactivity in mammary ductal epithelium of GEN relative to CAS and SPI, despite their comparable levels of membrane-localized E-cadherin and β-catenin. Identification of distinct GEN and SPI responsive genes in mammary epithelial cells may define early events contributing to tumor protection by diet relevant to the prevention of breast and other types of cancer. Experiment Overall Design: Female Sprague-Dawley rats, fed one of the three purified diets, were studied at postnatal day50. Total RNA( each RNA samples were extracted from #4 mammary gland from two animals under the same diet group) purified from non-tumor tissue within the proximal half of each colon, was used to prepare biotinylated probes, which were hybridized to Affymetrix RAE230 rat microarrays.
Project description:Analysis of gene expression in partial Dnmt3a deleted colon mucosa cells of APC(Min/+) mice. In the present study the influence of Dnmt3a deletion on colonic tumorigenesis, gene expression and DNA methylation was analyzed. Results provide important information about the role of Dnmt3a in colonic tumorigenesis.
Project description:The effect of dietary calcium and dairy proteins on adipose tissue gene expression profile in diet induced obesity Experiment Overall Design: 9-week-old C57Bl/6J-mice were divided into two groups (n=10/group). The control diet was a standard high-fat diet (60% of energy) low in calcium (0.4%). The whey protein diet was a high-calcium (1.8%) high-fat diet with whey protein isolate. After the 21-week treatment, the adipose tissue transcript profiling (2 mice/group) was carried out using Affymetrix Mouse Genome 430 2.0 array.
Project description:Obesity, characterized by augmented inflammation and tumorigenesis, is linked to genetic predispositions, such as FOXO3 polymorphisms. As obesity is associated with aberrant macrophages infiltrating different tissue including the colon, we aimed to identify FOXO3-dependent transcriptomic changes in macrophages that drive obesity-mediated colonic inflammation and tumorigenesis. We found that in mouse colons, high-fat-diet-(HFD)-obesity led to diminished FOXO3 levels and increased macrophages. Transcriptomic analysis of mouse peritoneal FOXO3-deficient macrophages showed significant differentially expressed genes (DEGs; FDR<0.05) similar to HFD-obese colon. These DEGs related pathways, linked to mouse colonic inflammation and tumorigenesis, were similar to those in inflammatory bowel disease (IBD) and human colon cancer. Additionally, we identified a specific transcriptional signature for the macrophage-FOXO3 axis (MAC-FOXO382), which separated the transcriptome of affected tissue from control in both IBD (p=5.2E-08) and colon cancer (p=1.9E-11), revealing its significance in human colonic pathobiologies. Further, we identified (heatmap) and validated (qPCR) DEGs specific to FOXO3-deficient macrophages with established roles both in IBD and colon cancer (IL-1B, CXCR2, S100A8, S100A9, and TREM1) and those with unexamined roles in these colonic pathobiologies (STRA6, SERPINH1, LAMB1, NFE2L3, OLR1, DNAJC28 and VSIG10). These findings establish an important understanding of how HFD-obesity and related metabolites promote colonic pathobiologies.