Effect of Dietary Supplementation of Selenium (Organic vs. Inorganic) on Liver Gene Expression Profile in Beef Heifers
ABSTRACT: Selenium (Se) is an essential nutrient for beef cattle health and commercial production. The molecular mechanisms responsible for the physiological responses of the animal to dietary Se supplementation, however, have not been evaluated. Furthermore, the potential effect of two chemical forms (organic vs. inorganic) of Se on gene expression by Se-sufficient cattle has not been evaluated. Microarray analysis using the GeneChip Bovine Genome Array (Affymetrix, Inc., Santa Clara, CA) was conducted to determine if dietary Se supplementation in organic vs. inorganic form (OSe vs. ISe) differentially affects the liver gene expression profile in growing beef heifers. Overall design: Sodium selenite (Prince Se Concentrate; Prince Agri Products, Inc., Quincy, IL) was used as the source of ISe form. Se-enriched yeast (Sel-Plex; Alltech, Inc., Nicholasville, KY) was used as the source of OSe form. Thirty Angus heifers (BW 393 ± 9 kg) were randomly assigned to 3 dietary treatments (n = 10): Control (Ctrl) group received no dietary Se supplementation; ISe treatment group daily received dietary supplementation of Se at 3 mg/animal from ISe source; OSe treatment group daily received dietary supplementation of Se at 3 mg/animal from OSe source. Six animals were randomly selected from each of 3 treatment groups for RNA extraction and microarray analysis.
Project description:Selenium (Se) is an essential nutrient for beef cattle health and commercial production. The molecular mechanisms responsible for physiological responses of the animal to dietary Se supplementation, however, have not been evaluated. Furthermore, the potential effect of two chemical forms (organic vs. inorganic) of Se on gene expression by Se-sufficient cattle has not been evaluated. Microarray analysis using the GeneChip Bovine Genome Array (Affymetrix, Inc., Santa Clara, CA) was conducted to determine if dietary Se supplementation in organic vs. inorganic form (OSe vs. ISe) differentially affects the liver gene expression profile in growing beef heifers. Sodium selenite (Prince Se Concentrate; Prince Agri Products, Inc., Quincy, IL) was used as the source of ISe form. Se-enriched yeast (Sel-Plex; Alltech, Inc., Nicholasville, KY) was used as the source of OSe form. Thirty Angus heifers (BW 393 ± 9 kg) were randomly assigned to 3 dietary treatments (n = 10): Control (Ctrl) group received no dietary Se supplementation; ISe treatment group daily received dietary supplementation of Se at 3 mg/animal from ISe source; OSe treatment group daily received dietary supplementation of Se at 3 mg/animal from OSe source. Six animals were randomly selected from each of 3 treatment groups for RNA extraction and microarray analysis.
Project description:Little is known regarding the relationship between Selenium (Se) concentrations in the liver and liver gene expression. Because most cow-calf operations in Se-poor soils provide enough Se in mineral mixes to avoid deficiency, the aim of this study was to determine the effects of 4 Se form supplementation strategies (none or inorganic, organic, or 1:1 inorganic:organic mix) on liver gene expression profiles using a Se-adequate model. Microarray analysis was conducted using the custom WT Btau 4.0 Array (version 1; GeneChip, Affymetrix, Inc., Santa Clara, CA, USA) to determine if dietary Se supplementation form differentially affects the hepatic gene expression profiles of maturing beef heifers. Sodium selenite was used as the source of inorganic Se and Se-enriched yeast was the source of organic selenium. Thirty-six Angus heifers (BW 400 ± 9.0 kg) were ranked on the Se concentration of their biopsied (day -14) liver sample and randomly assigned to one of four dietary Se treatments: Control (Ctrl) group received no exogenous dietary Se supplementation; inorganic (ISe) treatment group received daily dietary Se supplementation at 3 mg/ animal of the ISe form; organic (OSe) treatment group received daily dietary Se supplementation of 3 mg/ animal of OSe form; and the mix (1:1 ISe:OSe) received daily dietary Se supplementation of 3 mg/ animal of 50:50 mix of ISe and OSe forms. RNA was extracted from biopsied liver samples taken 168 days after initiation of Se supplementation and microarray analyses were conducted.
Project description:The potential for dietary supplementation with n-3 polyunsaturated fatty acids (n-3 PUFA) to improve reproductive efficiency in cattle has received much interest. The mechanisms by which n-3 PUFA may affect physiological and biochemical processes in key reproductive tissues are likely to be mediated by significant alterations in gene expression. We used microarrays to assess endometrial gene expression on day 17 of the estrous cycle in n-3 PUFA compared with control fed heifers. Beef heifers were supplemented with a rumen protected source of either a saturated fatty acid (CON; palmitic acid) or high n-3 PUFA (n-3 PUFA; 275 g) diet per animal per day for 45 days and global gene expression was determined in uterine endometrial tissue using an Affymetrix® oligonucleotide bovine array.
Project description:In many parts of the US, selenium (Se)-deficient soils dictate the necessity of supplementing this trace mineral directly to the diet of cattle, with the form of Se supplied known to affect tissue-level gene expression profiles and presumably function. Because a deficiency of Se will reduce fertility, including reduced biosynthesis of testosterone by the testis and an increased frequency of abnormalities in mature spermatozoa, we hypothesized that the form of Se supplemented to cows during gestation would affect the transcriptome of the neonatal bull calf testis. Microarray analysis using the Bovine gene 1.0 ST array (GeneChip; Affymetrix, Inc., Santa Clara, CA) was conducted to determine whether gestational form of supplemental Se affected gene expression profiles in the testis. GeneChip transcript annotations were last updated in January 2013 using the annotation update release 33 from the NetAffx annotation database. Twenty-four Angus cross cows were assigned randomly (n=8) to individual ad libitum intake of a common vitamin-mineral mix that contained 35 ppm of Se supplied as either inorganic (ISe, sodium selenite; Prince Se Concentrate, Prince Agri Products, Inc., Quincy, IL), organic (OSe, Sel-Plex; Alltech Inc., Nicholasville, KY), or a 50/50 mix of ISe/OSe (Mix) Se for 4 months prior to breeding and throughout gestation. Cows were managed under a fall-calving, forage-based, cow-calf production regimen at the University of Kentucky Princeton Research and Education Center. Testis tissue (ISe n=5; OSe n=4; Mix n=4) was collected within 2 days of birth, and RNA extracted for microarray analysis.
Project description:The goal of this study was to test the hypothesis that sodium selenite (ISe), SEL-PLEX (OSe), vs. a 1:1 blend (MIX) of ISe and OSe in a basal vitamin-mineral (VM) mix would differetianlly alter pituitary transcriptome profiles in growing beef steers commonly grazing an endophyte-infected tall fescue pasture. Predominately-Angus steers (BW = 183 ± 34 kg) were randomly selected from herds of fall-calving cows grazing E+ pasture and consuming VM mixes that contained 35 ppm Se as ISe, OSe, and MIX forms. Steers were weaned, depleted of Se for 98 d, and subjected to summer-long common grazing of an E+ pasture (0.51 ppm total ergovaline per ergovalinine; 10.1 ha). Steers were assigned (n = 8 per treatment) to the same Se-form treatments upon which they were raised. Selenium treatments were administered by daily top-dressing 85 g of VM mix onto 0.23 kg soyhulls, using in-pasture Calan gates. We collected pituitary samples and examine for changes in global expression pattern by microarray analysis. Overall design: 20 total samples were analyzed (n = 6 for ISe, and n=7 for both OSe and MIX).
Project description:The possible benefits of selenium (Se) supplementation are currently under investigation for prevention of certain cancers and treatment of neurological disorders. Little is known concerning the response of the brain to increased dietary Se under conditions of Se sufficiency, despite the majority of Se supplementation trials occurring in healthy subjects considered Se sufficient. We evaluated the transcriptional response of the zebrafish (Danio rerio) brain to supplementation with nutritionally relevant levels of dietary Se (sodium selenite) during conditions of assumed Se sufficiency. We used a microarray approach to analyze the global gene expression response of the brain to dietary Se supplementation for 14 days. The experiment used Affymetrix microarrays to compare whole brain RNA from 8 adult zebrafish (Danio rerio) fed a diet with control selenium levels (1.4ppmSe) and 8 fed a diet supplemented with sodium selenite (5.6ppmSe) for 14 days, and with an equal sex ratio within each diet.
Project description:In the present study, we studied the effect of dietary selenium (Se) supplementation on the transcriptomic profile of sheep. The main objective was to evaluate the effect of Se-supplementation on the overall transcriptome of sheep, the altered pathways, and the biological processes related to it . A custom oligo microarray platform (AMADID: 070119) was designed, then used to profile gene expression from 20 samples from 10 sheep at two time points (T0; before Se-supplementation, and T40; at the end of a 40-d Se-supplementation period). Isolated and purified total RNAs were individually hybridized to the custom (4x44k) DNA microarray. The comparison of control and treated animal transcriptomes revealed a large set of differentially expressed genes. After functional analysis and qPCR validation, the result showed several pathways and biological processes that have been altered following Se-supplementation to the diet. Overall design: Ten lactating crossbred ewes (3 to 4 y of age and 55 to 65 kg BW) were assigned to a before-and-after experimental design, where each animal served as its own control. The sheep have been acclimatized (4-wk) on a basal diet containing a maintenance level of Se (0.13 mg Se/kg DM). At the end of the 4-wk acclimatization period the sheep started to receive the supra Se-supplemented diet (0.45 mg Se/kg DM) for a 40-d period. Blood samples were collected at 2 time points [T0; one day before the supra Se-supplementation, and T40; at the end of the 40-d supra Se-supplementation phase]. Blood samples were collected from each individual animal directly into Paxgene blood collection tubes, processed and stored at -20˚C till further analyses. All samples yielded high quality RNA that was tested prior the microarray setup.
Project description:An abrupt transition from high forage to high fermentable diet may induce digestive disorders in the rumen. To date, the host mechanisms regulate the adaption to such dietary transition are largely unknown. To understand the molecular mechanisms involved in such phenomena, RNA-sequencing was performed to identify the changes in the transcriptomes of ruminal epithelia during a rapid high grain transition from 3% to 92% grain. In total, the expression of 11,044, 11,322 and 11,282 genes was detected in ruminal epithelia of beef heifers (n=15) fed 3%, 75% and 92% barley grain diet, respectively. When diet was changed from 75% to 92% grain, a significant difference was observed in the mean ruminal pH change among the individuals with five heifers decreased (DG; pH from 6.30 ± 0.09 to 5.87 ± 0.15, P < 0.01) and five other ones increased (UG; pH from 5.84 ± 0.42 to 6.35 ± 0.37, P < 0.05). In the ruminal epithelia of DG animals, the expression of genes involved in ketogenesis (HMGCL, P < 0.1) and lipid synthesis (SREBF2, P < 0.1; FABP4, P < 0.05) was increased, the abundance of genes involved in short chain fatty acid transporters (SMCT1, P < 0.1) and monocarboxylate transporters (MCT4, P < 0.1) was decreased. The function of “Concentration of lipid” was activated after 75% to 92% grain diet transition. Comparing to DG animals, the expression of ketogenesis (ACAT2, P < 0.05; HMGCS P < 0.1) and cholesterol synthesis related genes (HMGC and FDPs, P < 0.1) was deceased, while the expression of proton and cholesterol efflux related genes NHE3 and ABCA1 were increased (P < 0.05), and the function of “Storage of lipid” was inhibited in the ruminal epithelial of UG heifers. In addition, the function of differentially expressed (DE) genes in DG were involved in “T cell receptor signaling” and “complement and coagulation cascades” pathways, while the functions “metabolism of xenobiotics by cytochrome P450” and “p53 signaling pathway” were enriched for DE genes in UG animals. Furthermore, the single nucleotide polymorphisms (SNP) discovery by RNA-seq was performed, and SNP (g.46834311A > G) in FABP4 identified between two groups of animals (P < 0.1). The expression of genes involved in regulating lipid transport and fatty acid metabolism varied between DG and UG heifers during rapid 75% to 92% grain transition. The identified genes and SNP could be potential markers and may account for the varied ruminal pH responses between DG and UG heifers, which can be potentially applied in breeding and selecting beef cattle with more tolerance in dietary transition stress. Overall design: Forty five rumen papillae samples were collected from fifteen heathy beef heifers (15 samples were collected when fed 3%, 75% and 92% grain diet, respectively). Using Trizol reagent to extract the total RNA, and the mRNA expression was profiled.
Project description:Bovine mammary stem cells (MaSC) are a source of ductal and lobulo-alveolar tissue during development of mammary gland and its remodeling in repeating lactation cycles. We hypothesize that the number of MaSC, their molecular properties and interactions with their niche may be essential to determine the mammogenic potential in heifers. To verify this hypothesis we compared the number of MaSC and transcriptomic profile in mammary tissue of 2-year-old, non-pregnant dairy (Holstein-Friesian) and beef (Limousin) heifers. For identification and quantification of putative stem/progenitor cells in mammary tissue sections scanning cytometry was used with a new combination of MaSC molecular markers: stem cell antigen-1 (Sca-1) and fibronectin type III domain containing 3B (FNDC3B) protein. Double labeled cells were located mainly in the basal layers of mammary epithelium. Cytometric analysis of Sca-1pos FNDC3Bpos cells revealed significantly higher number in HF (2.94±0.35%) than in LM (1.72±0.20%) heifers. More advanced development of mammary tissue in HF heifers was accompanied by higher expression of intramammary hormones, growth factors, cytokines, chemokines and transcription regulators. The model of transcriptomic niche favorable for MaSC was associated with regulation of genes involved in MaSC maintanence, self renewal, proliferation, migration, differentiation, mammary tissue remodeling, angiogenesis, regulation of adipocyte differentiation, lipid metabolism and steroid and insulin signaling. In conclusion the high mammogenic potential in postpubertal dairy heifers is facilitated by a higher number of MaSC and up-regulation of mammary auto-, paracrine factors representing MaSC niche. Keywords: stem/progenitor cells, transcriptomics, mammary gland, dairy and beef heifers Two-condition experiment, LIM vs. HF. Pulled quarters of mammary glands form 10 LIM heifers (test) and 10 HF heifers (reference). Sample 3 and 4 are dye swaps.