Effect of glutamine on the systemic innate immune response in broiler chickens challenged with Salmonella pullorum.

BACKGROUND: The objective of this study was to evaluate the effects of glutamine on the growth performance and systemic innate immune response in broiler chickens challenged with Salmonella pullorum. A total of 600 one-day-old Arbor Acres broiler chickens were assigned randomly to 6 dietary treatments with 10 replicates for a 21-day feeding experiment. The experimental treatments were as follows: the control treatment (birds fed the basal diet), the Gln1 treatment, and the Gln 2 treatment (birds fed the basal diet supplemented with 0.5%, and 1.0% Glutamine, respectively). At 3 d of age, half of the birds from each treatment were challenged oral gavage with 2.0 × 104 CFU/mL of S. pullorum suspension (1.0 mL per bird) or an equivalent amount of sterile saline alone, which served as a control. RESULTS: The results showed that S. pullorum infection had adverse effects on the average daily feed intake, average daily gain, and feed conversion ratio of broiler chickens compared with those of the CON treatment on d 7, decreased the spleen and bursa of fabricius relative weights (except on d 21), serum immunoglobulin A (IgA),immunoglobulin G (IgG), and immunoglobulin M (IgM) concentrations, and spleen melanoma differentiation-associated gene 5 (MDA5) and laboratory of genetics and physiology gene 2 (LGP2) mRNA expression levels, and increased the mRNA expression levels of spleen Nodinitib-1 (NOD1), Toll-like receptors 2,4 (TLR2, TLR4), DNA-dependent activator of IFN-regulatory factors (DAI), mitochondrial antiviral-signaling protein (MAVS), P50, P65, and RelB on d 4, 7, 14, and 21. Supplementation with Gln improved the relative weights of the spleen and bursa of Fabricius (except on d 21), increased the serum IgA, IgG, and IgM concentrations and the mRNA expression levels of spleen MDA5 and LGP2, and decreased the mRNA expression levels of spleen NOD1, TLR2, TLR4, DAI, MAVS, P50, P65, and RelB of S. pullorum-challenged broiler chickens. CONCLUSION: These results indicate that Gln might stimulate the systemic innate immune responses of the spleen in broiler chickens challenged with S. pullorum.

Effects of dietary supplementation with glutamine on the lymphocyte proliferation and intestinal immune gene expression in broiler chickens infected with Salmonella Enteritidis.

An experiment was conducted to investigate the effects of glutamine (Gln) on the lymphocyte proliferation and intestinal immune relevant gene expression in broilers infected with Salmonella Enteritidis. 240 1-day-old broilers were divided randomly into four groups in a completely randomized design, each of which had 6 replicates. Birds were reared in battery cages for 21 days. The experimental groups were as follows: control group (unchallenged group, CON), basal diet; Salmonella Enteritidis challenged group (challenged with 2.0 × 104 CFU/mL of Salmonella Enteritidis, SCC), basal diet; Gln 1, basal diet plus Salmonella Enteritidis challenged plus Gln at 0.5% diet; Gln 2, basal diet plus Salmonella Enteritidis challenged plus Gln at 1.0% diet. The results showed that Salmonella Enteritidis infection led to some decrease in the relative weight of spleen and bursa (except at 21 d), lymphocyte percentage, number of proliferation peripheral blood T and B lymphocytes, and increased the heterophil percentage, H/L ratio, mRNA expression levels of TNF-α, NF-κB p65, IL-1ß, IL-6, and IL-8 in the jejunal and ileal mucosa compared with the measurements of these parameters in the CON group at d 4, 7, 14, and 21 (p < 0.05). On the other hand, chickens fed the Gln showed improved the relative weight of spleen and bursa, increased the lymphocyte percentage, number of proliferation peripheral blood T and B lymphocytes, and decreased the heterophil percentage, H/L ratio, and immune relevant gene expression in the jejunal and ileal mucosa compared with the measurements of these parameters in the SCC group (p < 0.05). These results suggest that Gln as a feed additive could be effective for reducing the detrimental effects of Salmonella Enteritidis infection, and increase the intestinal immune barrier function of broilers.

Effect of glutamine on the growth performance, digestive enzyme activity, absorption function, and mRNA expression of intestinal transporters in heat-stressed chickens.

To explore the effect of glutamine (Gln) on the growth performance, digestive enzyme activity, absorption function and mRNA expression of intestinal transporters in heat-stressed chickens, 540 21-day-old Arbor Acres broilers were randomly assigned to a control group (no stress, NS), Gln group (Chickens were administered 0.5% and 1.0% Gln, respectively), heat stress group (HT), and Gln + HT group (Chickens were administered 0.5% and 1.0% Gln, respectively). The chickens in the HT and Gln + HT groups were reared under HT (36 ± 1 °C for 10 h/d and 22 ± 1 °C for 14 h/d), for 21 days. In contrast to the NS group, heat stress caused a reduction in the body weight gain (BWG); feed intake (FI); activity of trypsin, lipase, alkaline phosphatases, Ca2+ and Mg2+ adenosine triphosphatases, and Na+-K+-ATPase; and content of glutathione and d-xylose (P < 0.05) in the other groups. In addition, compared to the F:G and expression levels in the NS group, the heat stress increased the feed intake:body weight gain (F:G) and mRNA expression levels of SGLT1, CaBP-D28k, and L-GSBP (P < 0.05). Furthermore, HT-challenged birds were pretreated with Gln, the BWG; FI; activity of trypsin, lipase, alkaline phosphatase, Ca2+ and Mg2+ adenosine triphosphatases, and Na+-K+-ATPase; and content of glutathione and d-xylose (P < 0.05) were dramatically increased, but it decreased the F:G and mRNA expression levels of SGLT1, CaBP-D28k, and L-GSBP (P < 0.05) in the HT group. In summary, Gln can effectively improve growth performance and may promote digestion and absorption in the gastrointestinal tract by mediating the mRNA expression level of nutrient transporters and Gln metabolism in heat-stressed broilers.

Effect of dietary oridonin supplementation on growth performance, gut health, and immune response of broilers infected with Salmonella pullorum.

BACKGROUND: The effects of dietary supplementation of oridonin (ORI) on growth performance, cecal microbiota, epithelium development and antioxidant and immune parameters of broilers infected with S. pullorum were studied. A total of 300 1-d-old male chicks were selected and divided into 5 trial groups (6 replicates of 10 chickens): 1) nonchallenge control chicks (CON), 2) chicks treated with Salmonella Challenged Control (SCC), 3) chicks treated with S. pullorum challenge and 50 mg/kg ORI (O1), 4) chicks treated with S. pullorum challenge and 80 mg/kg ORI (O2), and 5) chicks treated with S. pullorum challenge and 100 mg/kg ORI (O3). RESULTS: The results showed that S. pullorum had no effect on the feed intake (FI), body weight gain (BWG) or feed conversion ratio (FCR) of broilers compared with the values measured for the CON group (P > 0.05). However, compared with the characteristics of CON, S. pullorum showed effects on the counts of Salmonella and Lactobacillus at 7 d and at 14 d (P < 0.05), on jejunal development at 7 d (P < 0.05), and on jejunal immunoglobulin A (IgA) concentration at 7 d (P < 0.05). The addition of 100 mg/kg ORI had the greatest effect on the counts of Lactobacillus and Salmonella in cecal content (P < 0.05), malonaldehyde (MDA) content in the jejunum (P < 0.05), villi height of the small intestine, and IgA concentrations in the jejunum (P < 0.05). CONCLUSIONS: The results suggest that ORI can improve Salmonella-induced immune responses and protect intestinal health, not only through its immune inhibitory properties but also through its multi-protective effects on gut health.

Effects of oridonin on immune cells, Th1/Th2 balance and the expression of BLys in the spleens of broiler chickens challenged with Salmonella pullorum.

The aim of this study was to investigate the effects of oridonin (ORI) on the immune cells, Th1/Th2 balance and the expression of B lymphocyte stimulator (BLys) in the spleens of broilers infected with Salmonella pullorum. In a completely randomized design, 300 one-day-old AA male broilers were divided to 5 treatments. The groups included a noninfection control (CON) group receiveed a basal diet; a S. pullorum infect control group received the basal diet; and S. pullorum infect group receiveed the basal diet plus 50, 80, and 100 mg/kg ORI, respectively. The results showed that Salmonella challenge increased the relative weights of the spleen, white blood cell counts, lymphocyte and heterophil percentage, H/L ratio, the concentration and mRNA levels of spleen proinflammatory mediators, including tumor necrosis factor-α (TNF-α), interleukin-2 (IL-2), IL-4, IL-6, and IL-10, as well as the anti-inflammatory target Blys (P < .05), and modulated the Th1/Th2 balance (P < .05). ORI pretreatment decreased the relative weight of the spleen and inhibited the release and expression of these proinflammatory mediators and the anti-inflammatory target BLys. The results suggested that ORI supplementation may have immunosuppressive and multiple modulation effects on activated microglia through modulation of the Th1/Th2 balance and BLys expression.

Effects of dietary supplementation with oridonin on the growth performance, relative organ weight, lymphocyte proliferation, and cytokine concentration in broiler chickens.

BACKGROUND: The present study was conducted to investigate the effects of oridonin (ORI) on growth performance, relative organ weight, lymphocyte proliferation, phagocytic function of neutrophils, and cytokine concentration in broiler chickens. A total of 240 one-day-old Arbor Acres male broilers were randomly assigned to four treatments with six replicate pens of 10 broiler chickens per pen. Broiler chickens were fed diets based on four levels of dietary ORI (0, 50, 80 and 100 mg/kg) for a 42-d feeding trial. The experimental diets were fed in three phases: 1 to 14 d, 15 to 28 d and 29 to 42 d. RESULTS: The results indicated that ORI has no influence on the growth performance (P > 0.05). However, ORI increased the relative weights of spleen and bursa, the number of proliferation peripheral blood T and B lymphocytes, the phagocytic rate of neutrophils, as well as the Interleukin-2 (IL-2), Interleukin-4 (IL-4) and tumor necrosis factor-a (TNF-a) serum concentrations in serum in broilers at days 14, 28 and 42 (P < 0.05). CONCLUSIONS: In conclusion, ORI can enhance immune function and resistance to disease in broiler chickens by stimulating T and B lymphocyte formation, division, and proliferation, as well as the modulation of Th1/Th2 cytokine secretion profiles.

Influence of procyanidin supplementation on the immune responses of broilers challenged with lipopolysaccharide.

In the present study, the effect of dietary procyanidin (PCA, from pine needles) supplementation on the innate immunity of broilers were investigated. The experiment was designed as a 2 × 4 factorial arrangement (eight cages / treatment; six birds (one-day-old) / cage) with dietary PCA concentrations (0, 0.05, 0.075 and 0.1%) and two immune treatments (injection of lipopolysaccharide (LPS) (0.5 mg/kg body weight) or saline). LPS was dissolved in sterile 9 g/L (w/v) NaCl solution at 16, 18, 20 days of age to mimic immune stress. The remaining birds were injected with saline as a placebo. The results indicated that, prior to LPS challenge, the PCA diet had no significant effect on bird growth performance. The injection of LPS was also not associated with any significant changes in poultry performance. LPS injection increased the activity of nitrogen oxides (NOx) and the concentrations of inflammatory cytokines (interferon-γ (IFN-γ), interleukin-1ß (IL-1ß), IL-2, IL-4, IL-6 and IL-10) in serum; dietary PCA decreased these concentrations (P < 0.05) in the PCA 0.1% group, further illustrating the immune effect of PCA. In conclusion, PCA supplementation has a beneficial effect on LPS challenge, which may be associated with the inhibition of the secretion of cytokines and decrease in the proinflammatory marker NOx.

Effect of tributyltin on antioxidant ability and immune responses of zebrafish (Danio rerio).

Tributyltin (TBT) is a toxic compound released into aquatic ecosystems through antifouling paints. This study was designed to examine the effects of TBT on antioxidant ability and immune responses of zebrafish (Danio rerio). Three hundred sixty healthy zebrafish were randomly grouped into four groups and exposed to different doses of TBT (0, 1, 10 and 100ngL-1). At the end of 8 weeks, the fish were sampled, and antioxidant capability, immune parameters and immune-related genes were assessed. The results showed that with an increase in TBT dose, the concentration of malonaldehyde in the liver was significantly increased (p<0.05), whereas the activities of total superoxide dismutase, catalase and glutathione peroxidase were significantly decreased (p<0.05) compared to the control. The activity and expression of lysozyme and the content of immunoglobulin M were significantly decreased compared to those of the fish exposed to 0ngL-1 TBT (p<0.05). However, the expression of the HSP70, HSP90, tumor necrosis factor-α(TNF-α), interleukins (IL-1ß, IL-6), and nuclear factor-kappa B p65 (NF-κ B p65) genes were all enhanced with an increase in TBT dose. The results indicated that TBT induced oxidative stress and had immunotoxic effects on zebrafish.

The protective effect of procyanidin against LPS-induced acute gut injury by the regulations of oxidative state.

BACKGROUND: A 2 × 4 factorial arrangement of treatments was used to investigate the protective effect of procyanidin (PCA) against lipopolysaccharide (LPS)-induced acute gut injury by the regulations of oxidative state for a 21-days feeding trial. METHODS: A total of 384 1-days-old broiler chicks were assigned to 8 treatments with 8 replicate of 6 broiler chickens per pen. Broiler chickens fed diets based on 4 levels of dietary PCA (0, 0.05, 0.075 and 0.1 % of the requirements). Half of the birds from each treatment group were challenged with 0.9 % NaCl solution or LPS (250 µg/kg body weight, injection administered) at 16, 18 and 21 days of age. RESULTS: The results indicated that, prior to LPS challenge, there was no dietary effect on bird growth performance (P > 0.05). The injection of LPS were also not associated with any significant changes in poultry performance (P > 0.05). But LPS injection increased serum diamine oxidase (DAO) level and the malondialdehyde (MDA) content of intestinal mucosa (P < 0.05), cause adverse effects to the morphology of the small intestine (P < 0.05), decreased the glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activity of intestinal mucosa (P < 0.05). When LPS-challenged birds were pretreated with PCA, serum DAO concentration and MDA activity in jejunal and ileal mucosa were dramatically attenuated, and improved the morphology of the small intestine as well (P < 0.05). CONCLUSION: In conclusion, PCA is able to prevent LPS-induced oxidative stress response in vivo, improved the morphology of the small intestine. The beneficial effect of PCA may depend on increasing the activity of body's antioxidant enzymes and scavenging free radical activity.

Cloning, characterization and mRNA expression of interleukin-6 in blunt snout bream (Megalobrama amblycephala).

In the present study, the interleukin-6 gene (IL-6) cDNA in blunt snout bream (Megalobrama amblycephala) was identified and its expression profiles under ammonia stress and bacterial challenge were investigated. The IL-6 sequence consisted of 1045 bp, including a 696 bp ORF which translated into a 232 amino acid (AA) protein. The protein contained a putative signal peptide of 24 AA in length. IL-6 expression analysis showed that the it is differentially expressed in various tissues under normal conditions and the highest IL-6 level was observed in the intestine tissue, followed by the liver, and then in the gills. Under ammonia stress, the IL-6 mRNA level both in spleens and intestine increased significantly (P < 0.05), with the maximum levels attained at 6 h, 12 h (72, 10-fold, respectively). Thereafter, they all significantly decreased (P < 0.01) and returned to the basal value within 48 h. Whereas, in livers it slightly decreased at 3 h firstly (0.5-fold), and then significantly (P < 0.05) increased with the maximum level attained 12 h (3-fold). Further expression analysis showed that the mRNA level of IL-6 in spleens, intestine and livers of blunt snout bream all increased significantly (P < 0.05), with maximum values attained at 6 h, 3 h, 6 h (10, 6, 18-fold, respectively) after Aeromonas hydrophila (A. hydrophila) injection, and then decreased to the basal value within 24 h which suggested that IL-6 was involved in the immune response to A. hydrophila. The cloning and expression analysis of the IL-6 provide theoretical basis to further study the mechanism of anti-adverseness and expression characteristics under stress conditions in blunt snout bream.

The effects of natural and modified clinoptilolite on intestinal barrier function and immune response to LPS in broiler chickens.

The protection of intestinal barrier function and the anti-inflammatory effects of natural clinoptilolite (NCLI) and modified clinoptilolite (MCLI) were investigated in broilers that were repeatedly challenged with lipopolysaccharide (LPS). A total of 288 1-d-old broiler chicks were divided equally into three treatment groups: control, NCLI-treated (2%) and MCLI-treated (2%). Half of the birds from each treatment group were challenged with 0.9% NaCl solution or LPS (250µg/kg body weight, administered orally) at 16, 18 and 21d of age. The results indicated that, prior to LPS challenge, the diet had no effect on bird growth performance (P>0.05). The oral administration of LPS was also not associated with any significant changes in poultry performance (P>0.05). In LPS-challenged birds that were pretreated with NCLI (2%) or MCLI (2%), the LPS-induced increases in the plasma and intestinal mucosa concentrations of TNF-α, IL-1ß, IL-2, IL-6, IL-4 and IL-10 were dramatically attenuated. Additionally, significant decreases in the plasma d-lactic acid and diamine oxidase (DAO) levels were found in birds that were pretreated with NCLI or MCLI. Furthermore, both NCLI and MCLI reduced the sICAM-1 concentration in the intestinal mucosa. In conclusion, NCLI and MCLI are able to prevent the LPS-induced intestinal mucosa damage and inflammatory response in vivo. These beneficial effects suggest that NCLI and MCLI act as anti-inflammatory agents in part by inhibiting neutrophil infiltration and hyperactivation and by suppressing the secretion of various plasma and intestinal mucosa inflammatory mediators.