Differential mRNA expression of genes in the porcine adrenal gland associated with psychosocial stress

Abstract

To gain insight into the adrenal stress response, we analysed differential mRNA expression of genes associated with psychosocial stress in the pig (Sus scrofa domestica). Various levels of psychosocial stress were induced by mixing groups of unfamiliar pigs with different aggressiveness. We selected two experimental groups for comparison, each comprising eight animals, which differed significantly in aggressive behaviour and plasma cortisol levels. To identify differentially expressed genes, we compared the adrenal transcriptome of these two groups of pigs, using the Affymetrix GeneChip porcine Genome Array. Bioinformatic analysis revealed that psychosocial stress induced upregulation of transcripts enriched for functions associated with cholesterol accumulation and downregulation of transcripts enriched for functions associated with cell growth and death. These responses are similar to those induced by ACTH stimulation. Nevertheless, the majority of the differentially expressed genes were so far not described as ACTH responsive. Some, such as GAL and GALP, may have responded to sympathoadrenal stimulation. Several of the differentially expressed transcripts, such as AGT, are associated with processes modulating steroidogenic response of adrenocortical cells to ACTH. One of the most significant findings was upregulation of LOC100039095, comprising a precursor of the microRNA miR-202, pointing to a previously unrecognised layer of regulation of adrenal steroidogenesis by microRNA. Our study, performed under entirely physiological conditions, complements previous studies focusing either on a single adrenal tissue and/or on a single stimulus, and contributes to understanding of the fine-tuning of adrenal stress response.

Transcriptional responses of PBMC in psychosocially stressed animals indicate an alerting of the immune system in female but not in castrated male pigs

“…Accordingly, a genetic component of post-mixing aggressiveness was estimated in grower-stage pigs [ 10 , 15 , 16 ]. Further, there are a few microarray experiments which provide insight into transcriptional responses following psychosocial stress in adrenal gland [ 17 ] and liver tissue [ 18 ]. It appeared that psychosocial stress provoked expression patterns similar to those induced by ACTH stimulation.…”

Transcript variants of the porcine glucocorticoid receptor gene (NR3C1)

“…Circulating levels of glucocorticoids and target tissue response to them show large inter-individual variation and are directly and indirectly related to behavioral, physiological, and metabolic disturbances in mammals (de Groot et al, 2001;Murani et al, 2010Murani et al, , 2011Ponsuksili et al, 2012). The pig becomes increasingly important as an animal model for human diseases because of high physiological and genomic similarities between pigs and humans (Boullion et al, 2003;Kuzmuk and Schook, 2011).…”

Stress induced Salmonella Typhimurium recrudescence in pigs coincides with cortisol induced increased intracellular proliferation in macrophages

“…A period of stress results in the release of a variety of neurotransmitters, peptides, cytokines, hormones, and other factors into the circulation or tissues of the stressed organism [9-11]. Besides the fast-acting catecholamines, which are released by the sympathetic nervous system, the hypothalamic-pituitary-adrenal axis becomes activated, resulting in the release of the slow-acting glucocorticoids by the adrenal gland [12].…”