Project description:We evaluated the intestinal responses of pigs under zinc restriction and under different zinc sources through RNA-seq of ileal samples. We identified changes in genes related to zinc transport, immune response, cell proliferation, DNA damage and stress resposne. Our findings demonstrate that swine intestine is responsive to zinc restriction and can be a model sentinel tissue for human zinc deficiency. Further research is needed to define the intestinal responses to organic and inorganic zinc sources.
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:This study was designed to address key questions concerning the use of alternative protein sources for animal feeds and addresses aspects such as their nutrient composition and impact on gut function. The transcriptional response of intestinal mucosal tissue (jejunum and ileum) served as parameters for the local response. Growing pigs (BW 35 kg/approx. 10 weeks) were fed with experimental diets containing a single, common or new protein sources viz. soybean meal (SBM), black soldier fly larvae (BSF), spray dried blood plasma (SDPP), rapeseed meal (RSM), and wheat gluten meal (WGM) over a period of 4 weeks.
Project description:Dietary Methionine restriction (MR) has been demonstrated to induce a set of hepatic responses, including activation of hepatic stress response and suppression of hepatic lipogenesis. In the current study, we used two different protein sources to achieve MR. Casein was used in normal protein (NP, 20% casein) and low protein (LP, 5% casein) diet. Soy protein was used in 20Soy (20% soy), 20Soy+SAA (20% soy, Met and Cys was added back to match their concentration in NP diet), and 10Soy (11.5% soy, the Met concentration matches LP diet). Results show that mice that were fed LP and 10Soy diet have lower body weight and adiposity and increased food and water intake, energy expenditure, and serum FGF21 levels compared to their relative controls. The RNAseq experiment was conducted to compare the effect of MR using these two protein sources on the hepatic transcriptome.
Project description:This study was designed to address key questions concerning the use of alternative protein sources for animal feeds and addresses aspects such as their nutrient composition and impact on gut function. We used casein (CAS), spray dried porcine plasma (SDPP), soybean meal (SBM), and yellow meal worm (YMW) as protein sources. We have investigated the use of intestinal organoids as a model to test the effects of different protein sources on the intestinal epithelium. Mouse enteroids were exposed to different undigested protein sources (4% w/v, viz. soybean meal, SBM; casein, CAS; spray dried plasma protein, SDPP; and yellow meal worm, YMW) or DMEM as a control. Microarrays were used to detail the global gene expression.
Project description:Zinc (Zn) is an essential trace element for all life forms. Zn supplementation has been used to treat diarrheal disease in children, and in the U.S. swine industry at pharmacological levels to promote growth and fecal consistency, but underlying mechanisms explaining these beneficial effects remain unknown. Thus, we hypothesized that the benefits of pharmacological Zn supplementation were a result of changes in gene expression. For this study, liver RNA from newly weaned pigs fed dietary Zn as Zn oxide for 14 days at either adequate (150 Zn/kg) or pharmacological (2000 mg Zn/kg) levels was evaluated using a 70-mer oligonucleotide microarray. Interrogation of this microarray revealed 658 annotated transcripts (FDR ≤ 0.05) affected by pharmacological Zn supplementation. Relative real-time RT-PCR was used to confirm differential expression of two genes. Results suggest that feeding pharmacological Zn (2000 mg Zn/kg) affects genes involved in reducing oxidative stress and in amino acid metabolism, which are essential for cell detoxification and proper cell function.
Project description:We previously identified the ZTRE in genes involved in zinc homeostasis and showed that it mediates transcriptional repression in response to zinc. We now report that ZNF658 acts at the ZTRE. ZNF658 was identified by MALDI-TOF mass spectrometry of a band excised after EMSA using a ZTRE probe. The protein contains a KRAB domain and 21 zinc fingers. It has similarity with ZAP1 from Saccharomyces cerevisiae, which regulates the response to zinc restriction, including a conserved DNA binding region we show to be functional also in ZNF658. siRNA targeted to ZNF658 abrogated the zinc-induced, ZTRE-dependent reduction in SLC30A5 (ZnT5), SLC30A10 (ZnT10) and CBWD transcripts in human Caco-2 cells and the ability of zinc to repress reporter gene expression from corresponding promoter-reporter constructs. Microarray analysis of the effect of reducing ZNF658 expression by siRNA uncovered large changes in rRNA. We find that ZTREs are clustered within the 45S rRNA precursor. We also saw effects on expression of multiple ribosomal proteins. ZNF658 thus links zinc homeostasis with ribosome biogenesis, the most active transcriptional, and hence zinc-demanding, process in the cell. ZNF658 is thus a novel transcriptional regulator that plays a fundamental role in the orchestrated cellular response to zinc availability.
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.