Dietary protein modifies hepatic gene expression associated with oxidative stress responsiveness in growing pigs

Abstract

Understanding the basis for differences in nutrient requirements and for nutrient effects on health and performance requires an appreciation of the links between nutrition and gene expression. We developed and applied molecular probes to characterize diet-associated postabsorptive hepatic gene expression in growing pigs chronically fed protein-restricted diets based on either casein (CAS) or soy protein isolate (SPI). Eighty-eight expressed sequence tags (ESTs) were identified on the basis of diet-related changes in expression, by using an mRNA differential display method. Expression profiling based on transcription analysis by real-time reverse transcriptase-polymerase chain reaction showed that the SPI diet significantly changed the pattern of gene expression as compared with the CAS diet and allowed identification of coregulated genes. The expression of six genes involved in the metabolism of stress response (glutathione S-transferase, peptide methionine sulfoxide reductase, apolipoprotein A-I, organic anion transport polypeptide 2, calnexin, heat shock transcription factor 1) exhibited significant changes in the transcription level and indicated an increased oxidative stress response in pigs fed the SPI diet. Hierarchical clustering of gene expression data of all 33 ESTs analyzed across 14 pigs fed the two different diets resulted in clustering of genes related to the oxidative stress response with genes related to the regulation of gene expression and neuronal signaling.

Mechanisms through which sulfur amino acids control protein metabolism and oxidative status

“…Interestingly, certain nutritional conditions have been reported to cause up-regulation of Msr-A and Msr-B including, in relation to the present review, amino acid starvation in Escherichia coli [90] and the source of dietary protein in growing pigs [91]; one possible explanation for the up-regulation of Msr observed in pigs fed restricted protein diets based on soy protein isolate compared to casein might be the differences in protein amino acid patterns, particularly sulfur amino acids. Pamplona and Barja [92] and Sanz et al [93] recently reported an effect of dietary methionine levels on oxidative stress and longevity: lowering of methionine levels apparently decreases the sensitivity of proteins to oxidative damage and ROS production.…”

Application of disease-associated differentially expressed genes – Mining for functional candidate genes for mastitis resistance in cattle

“…Quantitative analysis of PCR products was carried out in the LightCycler ® (Roche, Mannheim, Germany) according to optimized PCR protocols essentially as described by [29] using the specific primers of the corresponding EST (Tab. I) and LightCycler DNA Master SYBR Green I ® (Roche, Mannheim, Germany).…”

Potato and soy peptides alter caecal fermentation and reduce serum non‐HDL cholesterol in rats fed cholesterol

“…Thus, the elevation of the hepatic LDL-R mRNA level in rats fed PPC is of particular importance. The differences in protein gene expression of potato and soy peptide-fed rats may be due to the differences in amino acid sequences as observed previously for soy protein and casein [33].…”