摘要：
This study evaluated the effect of an aluminosilicate mineral additive-Biotite V (BV) on growth performance, the immunological and adrenal responses in weaned pigs after Escherichia coli lipopolysaccharide (LPS) challenge. Thirty-two crossbred weaned pigs were used in this 2x2 factorial experiment, with dietary treatment (basal diet with or without 0.45% BV supplementation) and LPS challenge (challenged or not challenged) as two main factors. On day 14 and 21, pigs were injected intraperitoneally with either 100 mu g/kg body weight of LPS or an equivalent amount of sterile saline. Blood samples were collected 3 h after the first challenge followed by total and differential leukocyte counts and analysis of plasma tumor necrosis factor-alpha (TNF-alpha), prostaglandin E-2 (PGE(2)), cortisol, insulin, and biochemical parameters. Body weight and feed intake were measured weekly throughout the 4-week experiment. The results showed that both LPS challenges reduced average daily gain (ADG) (P < 0.05) and increased feed/gain (P < 0.001), and BV decreased feed/gain (P < 0.05) of immunology challenged pigs. The LPS challengexdiet interactions were observed for ADG (P < 0.05) and feed/gain (P < 0.05) during both challenge. LPS challenge reduced the number of white blood cells, lymphocytes, monocytes, and neutrophils (P < 0.05). LPS challengexdiet interaction was observed for plasma TNF-alpha (P < 0.05) concentration, showing decreased plasma TNF-alpha response to LPS challenged in pigs receiving BV. But no LPS challenge x diet interaction was observed for plasma cortisol or PGE(2). There was a diet effect for plasma insulin (P < 0.05) and glucose (P < 0.05), showing increased plasma insulin and decreased glucose with BV supplementation, but no LPS challengexdiet interaction was observed. We conclude that BV improved the weight gain and feed efficiency of weaned pigs during an immunological challenge by suppressing the proinflammatory cytokine release.
摘要：
Circulating concentration of the essential trace element selenium (Se) was significantly lower in inflammatory disorders. Although Se plays physiological roles mainly through the function of 25 selenoproteins, the response of the selenogenome in immune tissues during inflammatory reactions remains unclear. The objective of this study was to determine the Se retention and selenogenome expression in immune tissues during the lipopolysaccharide (LPS)-induced inflammatory response in porcine. A total of 12 male pigs were randomly divided into two groups and injected with LPS or saline. After 4 h postinjection, blood samples were collected and pigs were euthanized. Pigs challenged with LPS had 36.8 and 16.6 % lower (P < 0.05) Se concentrations in the serum and spleen, respectively, than those injected with saline. Moreover, the activities of GPX decreased (P < 0.05) by 23.4, 26.6, and 30.4 % in the serum, thymus, and lymph node, respectively, in the pigs injected with LPS. Furthermore, the LPS challenge altered (P < 0.05) the mRNA expression of 14, 16, 10, and 6 selenoprotein genes in the liver, spleen, thymus, and lymph node, respectively. Along with 10 previously reported selenoprotein genes, the response of Txnrd2, Txnrd3, Sep15, Selh, Seli, Seln, Selo, Selt, Selx, and Sephs2 to inflammatory reaction in immune tissues were newly illustrated in this study. In conclusion, the LPS-induced inflammatory response impaired Se metabolism and was associated with dysregulation of the selenogenome expression in immune tissues.
摘要：
Animal models are needed to study and understand a human complex disease. Because of their similarities in anatomy, structure, physiology, and pathophysiology, the pig has proven its usefulness in studying human gastrointestinal diseases, such as inflammatory bowel disease, ischemia/reperfusion injury, diarrhea, and cancer. To understand the pathogenesis of these diseases, a number of experimental models generated in pigs are available, for example, through surgical manipulation, chemical induction, microbial infection, and genetic engineering. Our interests have been using amino acids as therapeutics in pig and human disease models. Amino acids not only play an important role in protein biosynthesis, but also exert significant physiological effects in regulating immunity, anti-oxidation, redox regulation, energy metabolism, signal transduction, and animal behavior. Recent studies in pigs have shown that specific dietary amino acids can improve intestinal integrity and function under normal and pathological conditions that protect the host from different diseases. In this review, we summarize several pig models in intestinal diseases and how amino acids can be used as therapeutics in treating pig and human diseases.
摘要：
The experiment was conducted to study the effect of the glutamate (Glu) on muscle protein loss through toll-like receptor 4 (TLR4), nucleotide-binding oligomerization domain proteins (NODs), Akt/Forkhead Box O (Akt/FOXO) and mammalian target of rapamycin (mTOR) signaling pathways in LPS-challenged piglets. Twenty-four weaned piglets were assigned into four treatments: (1) Control; (2) LPS+0% Glu; (3) LPS+1.0% Glu; (4) LPS+2.0% Glu. The experiment was lasted for 28 days. On d 28, the piglets in the LPS challenged groups were injected with LPS on 100 mu g/kg body weight (BW), and the piglets in the control group were injected with the same volume of 0.9% NaCl solution. After 4 h LPS or saline injection, the piglets were slaughtered and the muscle samples were collected. Glu supplementation increased the protein/DNA ratio in gastrocnemius muscle, and the protein content in longissimus dorsi (LD) muscle after LPS challenge (P < 0.05). In addition, Glu supplementation decreased TLR4, IL-1 receptor-associated kinase (IRAK) 1, receptor-interacting serine/threonine- protein kinase (RIPK) 2, and nuclear factor-kappa B (NF-kappa B) mRNA expression in gastrocnemius muscle (P < 0.05), MyD88 mRNA expression in LD muscle, and FOXO1 mRNA expression in LD muscle (P < 0.05). Moreover, Glu supplementation increased p-Akt/t-Akt ratio (P < 0.05) in gastrocnemius muscle, and p-4EBP1/t-4EBP1 ratio in both gastrocnemius and LD muscles (P < 0.05). Glu supplementation in the piglets' diets might be an effective strategy to alleviate LPS-induced muscle protein loss, which might be due to suppressing the mRNA expression of TLR4 and NODs signaling-related genes, and modulating Akt/ FOXO and mTOR signaling pathways.
摘要：
Inflammatory bowel disease (IBD), which includes both ulcerative colitis and Crohn's disease, is a chronic relapsing inflammation of the gastrointestinal tract, and is difficult to treat. The pathophysiology of IBD is multifactorial and not completely understood, but genetic components, dysregulated immune responses, oxidative stress, and inflammatory mediators are known to be involved. Animal models of IBD can be chemically induced, and are used to study etiology and to evaluate potential treatments of IBD. Currently available IBD treatments can decrease the duration of active disease but because of their adverse effects, the search for novel therapeutic strategies that can restore intestinal homeostasis continues. This review summarizes and discusses what is currently known of the effects of amino acids on the reduction of inflammation, oxidative stress, and cell death in the gut when IBD is present. Recent studies in animal models have identified dietary amino acids that improve IBD, but amino acid supplementation may not be adequate to replace conventional therapy. The animal models used in dietary amino acid research in IBD are described.
关键词：
MicroRNAs;muscle fiber type;muscle protein synthesis;myogenesis;signal proteins;SNP.
摘要：
Pork is one of the most economical sources of animal protein for human consumption. Meat quality is an important economic trait for the swine industry, which is primarily determined by prenatal muscle development and postnatal growth. Identification of the molecular mechanisms underlying skeletal muscle development is a key priority. MicroRNAs (miRNAs) are a class of small noncoding RNAs that have emerged as key regulators of skeletal muscle development. A number of muscle-related miRNAs have been identified by functional gain and loss experiments in mouse model. However, determining miRNA-mRNA interactions involved in pig skeletal muscle still remains a significant challenge. For a comprehensive understanding of miRNA-mediated mechanisms underlying muscle development, miRNAome analyses of pig skeletal muscle have been performed by deep sequencing. Additionally, porcine miRNA single nucleotide polymorphisms have been implicated in muscle fiber types and meat quality. The present review provides an overview of current knowledge on recently identified miRNAs involved in myogenesis, muscle fiber type and muscle protein metabolism. Undoubtedly, further systematic understanding of the functions of miRNAs in pig skeletal muscle development will be helpful to expand the knowledge of basic skeletal muscle biology and be beneficial for the genetic improvement of meat quality traits.
