Previous studies on intestinal gene expression in fish indicated a reduction in cell proliferation or differentiation associated with dietary FO replacement by VO, possibly due to lower levels of membrane LC PUFA and reduced oxida tive stress. In the present study, no major impact on cell proliferation was apparent in the intestinal transcrip tome selleck products or proteome data. Two transcripts related to cell proliferation, PA2G4 and cyclin G1, were slightly down regulated in fish fed VO, but in mammals these Inhibitors,Modulators,Libraries have op posing effects and, furthermore, two mammalian PA2G4 isoforms have been shown to have opposite effects in cellular proliferation and hence results are inconclusive. Previously, expression of caspases, effectors of con trolled cell death or apoptosis, was affected by replace ment of dietary FO by VO in fish.
Apoptosis is particularly important in organs with high rates of cellu lar turnover such as intestine but, in addition to main taining normal gut function, apoptosis may be affected by pathological or toxic conditions, including those induced by environmental chemical contaminants. In the present study, expression Inhibitors,Modulators,Libraries of CASP3B was up regulated in salmon fed VO, particularly in the Lean family group and a similar, non significant trend was observed for CASP6A B. As ROS are important signalling molecules in apoptotic processes, these results could be linked to a cytotoxic effect causing increased oxidative stress in VO. Relevant to the above was the up regulation of galectin 2 in the proteome of salmon fed VO.
Galectins are pleiotropic regulators of immune functions and are up regulated by injury and infectious conditions, have well recognized modulatory roles in mammalian intestinal inflammatory diseases, and their mode of ac tion involves induction of apoptosis. The lack of major effects on cell proliferation and only slight up regulation of CASP3 and LGALS2 suggests that any contaminant Inhibitors,Modulators,Libraries doses experienced by the fish were unlikely to have caused any serious morphophysiological damage in the intestine. As similar trends were not seen in the hepatic transcriptome of these individuals, this may suggest intestine can potentially metabolize and detoxify xenobiotics present in the diet. Furthermore, there were no growth or general performance issues with these fish. Therefore, the data do not imply abnormal gastro intestinal functions or effects on final product quality.
Effect of genotype in intestinal transcriptome and proteome Contrary to diet, genotype did not have a major impact on metabolism genes, apart from transcripts related to the proteasomal degradation pathway including a strong down regulation of PSMB8 in Lean fish, particularly Inhibitors,Modulators,Libraries fed Inhibitors,Modulators,Libraries VO. This gene has been recently found to have a mo lecular evolution history Vandetanib hypothyroidism that suggests a very strong se lective pressure for its functional dimorphism to be maintained in vertebrates.