Molecular cloning, characterization and expression of the energy homeostasis-associated gene in piglet.

The energy homeostasis-associated (Enho) gene encodes a secreted protein, adropin, which regulates the expression of hepatic lipogenic genes and adipose tissue peroxisome proliferator-activated receptor γ, a major regulator of lipogenesis. In the present study, the porcine (Sus scrofa) homologue of the Enho gene, which was named pEnho, was amplified by reverse transcriptase polymerase chain reaction (RT-PCR) using oligonucleotide primers derived from in silico sequences. The gene sequence was submitted into the GenBank of NCBI, and the access number is GQ414763. The pEnho encodes a protein of 76 amino acids which shows 75% similarity to Homo sapiens adropin. The expression profile of pEnho in tissues (liver, muscle, anterior jejunum, posterior jejunum, and ileum) was determined by quantitative real-time RT-PCR. pEnho was localized on porcine chromosome 10 and no introns were found. In conclusion, pEnho was cloned and analysed with the aim of increasing knowledge about glucose and lipid metabolism in piglets and helping to promote the health and growth of piglets through adropin regulation.

Up-regulated expression of peroxisome proliferator-activated receptor gamma in the hypothalamic-pituitary-adrenal axis of weaned pigs after Escherichia coli lipopolysaccharide challenge.

The expression of peroxisome proliferator-activated receptor gamma (PPARgamma) was investigated in the hypothalamic-pituitary-adrenal (HPA) axis of weaned pigs after injection with 100 microg/kg bodyweight Escherichia coli lipopolysaccharide (LPS) (n=6) and control pigs injected with sterile saline (n=6). LPS increased PPARgamma mRNA and protein expression in the hypothalamus (23.8 and 3.1-fold relative to controls, respectively), pituitary gland (9.2 and 2.0-fold, respectively) and adrenal gland (3.5 and 2.3-fold, respectively) (P<0.05). LPS also induced an increase in PPARgamma immunohistochemical staining in the hypothalamus (1.3-fold), adenohypophysis (1.3-fold), adrenal cortex (1.4-fold) and adrenal medulla (1.6-fold) (P<0.05). Concurrent with up-regulated expression of PPARgamma, LPS increased the concentrations of plasma corticotrophin-releasing hormone (2.1-fold) and adrenocorticotrophin (1.4-fold) (P<0.05). LPS also induced elevations of interleukin 6 and tumour necrosis factor alpha mRNA levels in the hypothalamus (4.0 and 3.2-fold, respectively), pituitary gland (20.7 and 5.1-fold, respectively) and adrenal gland (3.9 and 3.3-fold, respectively) (P<0.05). PPARgamma may play a role in the regulation of neuroendocrine responses associated with immunological stress in pigs.