The current proteomic landscape of the porcine liver.

The main objective of the study was to create a reproducible protein map of the liver in healthy growing piglets. The analysis was performed on liver homogenates obtained from 8 castrated male piglets (PIC x Penerlan P76) at the 50 days. Two-dimensional electrophoresis and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry allowed to determine the proteomic profile of the liver. Liver proteins were separated at pH 4 - 7, followed by 12% SDS-PAGE. As a result, 470 ± 44 spots were present on the 2-D maps, of which 265 were successfully identified, representing products of 142 unique genes. Of these, 26 gene products have not been previously observed on the protein maps of porcine liver. Gene ontology analysis showed that the most of identified gene products belonged to the known metabolic pathways: protein processing in endoplasmic reticulum, arginine and proline metabolism, microbial metabolism in diverse environments, carbon metabolism, Epstein-Barr virus infection, propionate metabolism, biosynthesis of amino acids, proteasome. These results can undoubtedly serve as a useful and prospective prerequisite for the future analysis of the liver proteome changes in different physiological and pathophysiological conditions.

Dietary chicory root and chicory inulin trigger changes in energetic metabolism, stress prevention and cytoskeletal proteins in the liver of growing pigs - a proteomic study.

Currently, a wide array of plant preparations exerting health-promoting properties are commonly used as feed additives. Among them, Cichorium intybus L. have gained considerable attention as a source of compounds showing prebiotic character. Large body of evidence suggests that products of prebiotic fermentation (short-chain fatty acids) may influence the expression of genes encoding liver enzymes involved in the regulation of energetic metabolism. Given the above, the present study was aimed at estimating the influence of a diet supplemented with chicory root or water extract of chicory inulin on liver proteome in growing pigs. The study was performed on 24 castrated male piglets (PIC × Penarlan P76). Animals were assigned to three equal groups (n = 8) and fed cereal-based isoenergetic diets: control and supplemented with 2% of inulin extract from chicory root or 4% of dried chicory root. Liver proteins were separated using two-dimensional electrophoresis, followed by the identification of statistically valid protein spots with the aid of MALDI-TOF mass spectrometry. Both experimental factors significantly modulated the expression of liver proteins associated with energetic metabolism, particularly those involved in cholesterol and triglyceride metabolism. Additionally, both dietary additives induced increased expression of proteins involved in hepatocyte protection against oxidative stress. In the present study, we have shown for the first time that diet supplementation with dried chicory root or inulin caused significant changes in the expression of liver cytoskeletal proteins. Close attention should be paid to the downregulation of cytokeratin 18, hepatic acute phase protein that can enhance the anti-inflammatory properties of inulin-type fructans.