Project description:The starch, acting as the major energy-producing component of the daily diet, is the main carbohydrate in mammal nutrition. However, the nutritional value of starch can vary widely depending upon its source and site of digestion. The distinct physiological responses were previously observed both in human and other mammals, but still little is known about the underlying mechanisms regarding the metabolic shifts due to the intake of various dietary starches. Here, we assessed the overall metabolic changes in weaned pigs induced by different dietary starch sources at the transcriptome level. Sixteen weaned pigs (DurocÃLandraceÃYorkshire) were selected and randomly allotted to diets containing either wheat (WH) or cassava (CA) starch as the energy source (n=8). We measured serum metabolites and hormones and generated transcriptional profiles of liver. 648 genes in liver were differentially expressed in response to dietary starch sources. Pathway analysis indicated that dietary starch sources altered both carbohydrate and lipid metabolism in liver. In contrast, CA may be more healthful as dietary energy source than WH by down-regulating lipogenesis and steroidogenesis in liver. Sixteen weaned pigs (DurocÃLandraceÃYorkshire) with an average initial body weight of 7.37±0.25 kg were selected and randomly allotted to two dietary treatments (either wheat or cassava starch as the energy source) for 21 d. At the end of the trial, the liver tissue were collected for transcriptome analysis using Agilent porcine microarrays.
Project description:Diets rich in carbohydrates not only lead to obesity but also contribute to the liver metabolic diseases. Starch is the major energy source of the daily diet. However, little is known about the metabolic changes due to the intake of different dietary starches. Our aim was to assess the overall metabolic changes at the transcriptome level. Animal model was used, and a total of 16 weaned pigs were randomly allotted to two experimental diets containing either of cassava starch (CS) or maize starch (MS) during 21 days. At the end of the trial, liver tissues were sampled and used for analysis of digestive enzymes, metabolites and transcriptomes. The growth performance was not affected by dietary starch sources. However, CS-feeding significantly increased the serum insulin and cholesterol concentrations (P<0.05). The liver triglyceride and cholesterol content were both elevated by CS-feeding (P<0.05). Microarray analysis led to the identification of 648 genes differentially expressed in liver (P<0.05). The CS-feeding activated the transcription of lipogenic genes such as HMGR and FASN, but decreased the expression of lipolytic genes such as ACOX1, PPARA and FBP. The microarray results correlated well with the measurements of several key enzymes involved in hepatic lipid metabolisms. These results suggested that dietary starch source alters hepatic transcriptome in weaned pigs. The slowly digestible starch (i.e. MS) seemed to be more healthful for mammals as the dietary energy supplier by transcriptional down-regulation of lipogenesis and steroidogenesis.
Project description:Enterotoxigenic Escherichia coli (ETEC) is a major cause of diarrhoea in children in resource-limited countries and of travellers diarrhoea. The ileal proteomics change after ETEC challenge is less characterised. Here in this study changes of ileal proteins post ETEC challenge in weaned pigs are studied. In total, 5151 ileal proteins were successfully annotated and 9 proteins had significantly different abundance between the ETEC and CON pigs.
Project description:Fucoidan is a high-molecular polysaccharide whose main constituent is sulfated fucose. Extensive studies have demonstrated numerous interesting biological activities for fucoidan. We specifically focused on the anti-proliferation activity of fucoidan and examined the underlying mechanism in MKN45 gastric cancer cells. BrdU assay revealed that fucoidan impeded the MKN45 cell cycle by approximately 50%, and clonogenic assay also showed that fucoidan inhibited cell proliferation. Preliminary examinations of fucoidan using LDH assay showed no immediate cytotoxic effects at 24-h exposure. However, longer time courses revealed inhibition of cell growth at 4 days in a dose-dependent manner. Microarray analysis in MKN45 cells treated with fucoidan identified genes that were upregulated and downregulated in response to fucoidan, including MAP3K5, or ASK1 (apoptosis signal-regulating kinase), which was upregulated by 1.38-fold. Western blot confirmed that fucoidan increased ASK1 protein levels, while reducing the levels of phosphorylated ASK1. Reduction of ASK1 by siRNA decreased proliferation of MKN45 cells. Our findings show that fucoidan may suppress cellular proliferation and DNA synthesis in MKN45 cells by suppressing the ASK1-p38 signaling pathway through reduction of phosphorylated ASK1 levels.
Project description:Oligo-fucoidan (OF), a sulfated polysaccharide extracted from brown seaweed, exhibits anti-inflammation and antitumor effects, however, knowledge concerning the detailed mechanism of oligo-fucoidan on liver cells is obscure. In this study, we investigate the effect of oligo-fucoidan in normal hepatocytes using transcriptomic analysis. Using an oligo-fucoidan oral gavage in adult wild-type zebrafish, we then used microarrays to detail the global programme of gene expression after fucoidan treatment and identified distinct classes of up- and down-regulated genes during this process.
Project description:Hepatocellular carcinoma is the fourth leading cause of cancer-related deaths worldwide. Many carcinogens induce inflammation and cirrhosis, and eventually develop into liver cancer. Fucoidan is sulfated polysaccharide that is mainly found in brown seaweeds. In this study, we investigated the effects and mechanisms of low molecular weight fucoidan (i.e. oligo-fucoidan) preventing hepatocarcinogenesis using HBx,Src, and HBx,Src,p53-/+ transgenic zebrafish liver cancer model. Using an oligo-fucoidan oral gavage in adult transgenic zebrafish, we then used microarrays to detail the global programme of gene expression after fucoidan treatment and identified distinct classes of up- and down-regulated genes during this process.
Project description:Bacteroides thetaiotaomicron, one of the most eminent representative gut commensal Bacteroides species, is able to use the L-fucose in host-derived and dietary polysaccharides to modify its capsular polysaccharides and glycoproteins through a mammalian-like salvage metabolic pathway. This process is essential for the colonization of the bacteria and for symbiosis with the host. However, despite the importance of fucosylated proteins (FGPs) in Bacteroide thetaiotaomicron, their types, distribution, and functions remain unclear. In this project, the effects of different saccharide (glucose, corn starch, mucin, and fucoidan) nutrition conditions on FGP expressions and fucosylation are investigated using a chemical biological method based on metabolic labeling and bioorthogonal reaction. According to the results of label-free quantification, 559 FGPs (205 downregulated and 354 upregulated) are affected by the dietary conditions. Of these differentially expressed proteins, 65 proteins show extremely sensitive fucosylation levels. Specifically, the fucosylation of the chondroitin sulfate ABC enzyme, Sus proteins, and cationic efflux system proteins varies significantly upon the addition of mucin, corn starch, or fucoidan. Moreover, these polysaccharides can trigger an appreciable increase in the fucosylation level of the two-component system and ammonium transport proteins. These results highlight the efficiency of the combined metabolic glycan labeling and bio-orthogonal reaction in enriching the intestinal Bacteroide glycoproteins. Moreover, it emphasize the sensitivity of Bacteroides fucosylation to polysaccharide nutrition conditions, which allows for the regulation of bacterial growth.
Project description:Miniature pigs are useful model animal for gene expression studies on dietary-induced hyperlipidemia, because they have similar digestive physiology to human. Two typical dietary components were used for dietary-induced hyperlipidemia miniature pig models. One is a high-fat and high-cholesterol diet (HFCD) containing 15% lard and 2% cholesterol, the other is a high-fat, high-cholesterol and high-sucrose diet (HFCSD) containing 15% lard, 2% cholesterol and 37% sucrose. Whole blood gene expression in HFCD, HFCSD and control male miniature pigs was measured at 10, 19 and 27 weeks of feeding periods.M-cM-^@M-^@White blood cell gene expression in HFCD, HFCSD and control male miniature pigs was measured at 27 weeks of feeding period.
Project description:This study was performed to determine the effects of dietary fat sources, i.e., beef tallow, soybean oil, olive oil and coconut oil (each 3% in feed), on the growth performance, meat quality and gene expression in growing-finishing pigs. The results of this study indicate that the type of dietary fat affects fatty acid composition and insulin signaling-related gene expression in the longissimus dorsi muscle of pigs. Effects of dietary fat types on meat quantity, meat quality and gene expression in pig.