Abstract
To gain insight on the impart of high-grain diets on liver metabolism in ruminants, we employed a comparative proteomic approach to investigate the proteome-wide effects of diet in lactating dairy goats by conducting a proteomic analysis of the liver extracts of 10 lactating goats fed either a control diet or a high-grain diet. More than 500 protein spots were detected per condition by two-dimensional electrophoresis (2-DE). In total, 52 differentially expressed spots (≥2.0-fold changed) were excised and analyzed using MALDI TOF/TOF. Fifty-one protein spots were successfully identified. Of these, 29 proteins were upregulated, while 22 were downregulated in the high-grain fed vs. control animals. Differential expressions of proteins including alpha enolase, elongation factor 2, calreticulin, cytochrome b5, apolipoprotein A-I, catalase, was verified by mRNA analysis and/or Western blotting. Database searches combined with Gene Ontology (GO) analysis and KEGG pathway analysis revealed that the high-grain diet resulted in altered expression of proteins related to amino acids metabolism. These results suggest new candidate proteins that may contribute to a better understanding of the signaling pathways and mechanisms that mediate liver adaptation to high-grain diet.
Highlights
Current feeding practices in the dairy industry involve the use of high grain diets, either to meet the energy demands for high milk production, or due to shortages in forage-based feed
Global identification of differentially expressed proteins To understand the influence of diet type on liver metabolism, we employed proteomic tools (2-DE and MALDI-TOF/TOF) to globally identify proteins that were differentially expressed in the
The gels were analyzed by PDQuest software (Bio-Rad, USA), which is commonly used in proteomic research
Summary
Current feeding practices in the dairy industry involve the use of high grain diets, either to meet the energy demands for high milk production, or due to shortages in forage-based feed. Nutrient required for milk synthesis (amino acids, fatty acids, glucose, etc.) must be transported form the rumen and gut to the liver to undergo metabolic conversion. The best-known functions of the liver include bile production, lipid metabolism, hematopoiesis, and glucose metabolism. The effects of a high-grain diet on liver function ruminants such as cows and goats are not well understood. We hypothesized that a high-grain diet could significantly alter hepatic metabolism. Given the complexity of biological systems, high-throughput profiling is necessary to better understand such global effects. Advances in bioinformatics software and analysis methods have greatly facilitated high-throughput profiling efforts
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
