Yue Shang

The effect of dietary fructooligosaccharide supplementation on growth performance, intestinal morphology, and immune responses in broiler chickens challenged with Salmonella Enteritidis lipopolysaccharides

This study was conducted to examine the effects of fructooligosaccharide (FOS) supplementation on growth performance, lymphoid organ weight, intestinal morphology, and immunological status in broilers (n=180) challenged with Salmonella Enteritidis lipopolysaccharides (LPS). Birds were randomly assigned into a 3×2 factorial arrangement that included 1) 3 dietary treatments from d one to 21: positive control (PC), wheat-corn-soybean meal based diet contained antibiotics (virginiamycin and monensin); negative control (NC), as PC without antibiotics; and NC+FOS, as NC supplemented with 0.5% FOS, and 2) 2 intraperitoneal injections: 2 mg/kg Salmonella Enteritidis LPS or sterile phosphate buffered saline (PBS) on d 21. Growth performance and relative lymphoid organ weight were not significantly different among the treatments. Villus height, crypt depth, and total mucosa thickness were significantly increased (P<0.05) in the ileum of broiler chickens fed NC+FOS when compared to PC and NC. Birds in NC+FOS treatment had reduced heterophil but increased monocyte count when compared to NC (P<0.05). Significant diet×challenge interaction was observed on natural IgY levels (P<0.0001), and a significant dietary effect was observed on specific IgY levels in chickens fed NC+FOS (P=0.003). Supplementation of FOS also increased the expression of interleukin (IL)-1ß, -10, and interferon (IFN)-γ mRNA in the ileum of the birds. In summary, Salmonella Enteritidis LPS challenge established significant differences in the immune responses in broiler chickens. FOS supplementation increased ileal mucosa thickness and elevated the expressions of certain cytokine genes. It also led to the alteration of leukocyte compositions and serum IgY levels in response to LPS challenge, suggesting FOS supplementation may be effective to induce protective outcomes in gut health and immunity of broiler chickens.

Downregulation of Glutathione Biosynthesis Contributes to Oxidative Stress and Liver Dysfunction in Acute Kidney Injury.

Ischemia-reperfusion is a common cause for acute kidney injury and can lead to distant organ dysfunction. Glutathione is a major endogenous antioxidant and its depletion directly correlates to ischemia-reperfusion injury. The liver has high capacity for producing glutathione and is a key organ in modulating local and systemic redox balance. In the present study, we investigated the mechanism by which kidney ischemia-reperfusion led to glutathione depletion and oxidative stress. The left kidney of Sprague-Dawley rats was subjected to 45 min ischemia followed by 6 h reperfusion. Ischemia-reperfusion impaired kidney and liver function. This was accompanied by a decrease in glutathione levels in the liver and plasma and increased hepatic lipid peroxidation and plasma homocysteine levels. Ischemia-reperfusion caused a significant decrease in mRNA and protein levels of hepatic glutamate-cysteine ligase mediated through the inhibition of transcription factor Nrf2. Ischemia-reperfusion inhibited hepatic expression of cystathionine γ-lyase, an enzyme responsible for producing cysteine (an essential precursor for glutathione synthesis) through the transsulfuration pathway. These results suggest that inhibition of glutamate-cysteine ligase expression and downregulation of the transsulfuration pathway lead to reduced hepatic glutathione biosynthesis and elevation of plasma homocysteine levels, which, in turn, may contribute to oxidative stress and distant organ injury during renal ischemia-reperfusion.

The effect of phytase and fructooligosaccharide supplementation on growth performance, bone quality, and phosphorus utilization in broiler chickens

An experiment was conducted to investigate the effects of phytase and 2 levels of fructooligosaccharide (FOS) supplementation on growth performance, bone mineralization, and P utilization of broiler chickens. A total of 210 day-old male broiler chickens (Ross) were randomly placed into 7 dietary treatments consisting of 6 replicates with 5 birds per pen. The experiment was designed as an augmented 2 × 3 factorial arrangement with 0 or 500 U/kg of phytase and 0, 0.5% or 1% of FOS added to a reduced Ca (0.8%) and available P (0.25%) negative control diet (NC). A positive control diet (PC) that contained 1% Ca and 0.45% available P was also included. During the entire experimental period, phytase supplementation significantly improved (P < 0.05) the feed conversion ratio (FCR), BW gain (BWG), and feed intake. Birds fed the PC diet showed significantly higher bone mineral density (BMD) and bone mineral content (BMC) in both femur and tibia bones (P < 0.0001) than those fed the NC diet. Phytase supplementation increased femur BMD (P < 0.05), whereas FOS decreased femur BMD and BMC (P < 0.05). Phosphorus utilization was significantly higher for the NC diet (P < 0.0001). Phytase alone and in combination with 0.5% FOS increased P utilization significantly when compared with other treatments (P < 0.05). Fructooligosaccharides, especially at the level of 0.5%, increased P retention. In conclusion, phytase supplementation in low Ca and P diets improved growth performance, bone quality, and P utilization. However, supplementing NC diets with phytase and FOS did not result in bone mineralization values comparable with that of the PC diet. The application of dietary FOS alone had a negative effect on broiler bone quality.

Effect of Dietary Fructooligosaccharide (FOS) Supplementation on Ileal Microbiota in Broiler Chickens

The dietary effect of fructooligosaccharide (FOS) supplementation as an alternative to antibiotics on ileal mucosa and digesta microbiota was investigated in broiler chickens (n = 180). The study included three dietary treatments from d1 to 21: 1) positive control (PC), a wheat-corn-soybean meal based diet containing antibiotics (virginiamycin and monensin); 2) negative control (NC), as wheat-corn-soybean meal based diet without antibiotics; and 3) NC + FOS, as NC diet supplemented 0.5% of FOS. Ileal mucosa and digesta were collected and subjected to 16S rRNA-based next generation sequencing. No significant difference on α-, ß-diversity and bacterial phyla was observed between ileal mucosa and digesta or between the three dietary treatments. Partial least square discriminant analysis and Venn analysis showed that different bacterial genera were associated with different ileal sites or diets. A distinct distance on ileal mucosa bacteria communities were observed between PC and NC + FOS dietary treatments. FOS supplementation increased the number of unique genera and resulted in a more diverse microbiota in the ileal mucosa when compared with PC and NC groups. Furthermore, microorganisms that have pathogenic properties such as Helicobacter and Desulfovibrio were found significantly reduced when compared between NC and NC + FOS groups in the ileal mucosa. Lachnospiraceae (f) was greater in the ileal mucosa than that in the digesta, particularly among the NC + FOS dietary group. Overall, supplementing FOS in broiler chicken diets may be able to modulate gut microbiota in favor of chicken health, which in turn, can be used as an alternative method to replace antibiotic growth promoters (AGPs). Future investigation on the mechanism of FOS and other prebiotic products as dietary supplements is warranted.

Oxidized phosphatidylcholines are produced in renal ischemia reperfusion injury

Background The aim of this study was to determine the individual oxidized phosphatidylcholine (OxPC) molecules generated during renal ischemia/ reperfusion (I/R) injury. Methods Kidney ischemia was induced in male Sprague–Dawley rats by clamping the left renal pedicle for 45 min followed by reperfusion for either 6h or 24h. Kidney tissue was subjected to lipid extraction. Phospholipids and OxPC species were identified and quantitated using liquid chromatography coupled to electrospray ionization tandem mass spectrometry using internal standards. Result We identified fifty-five distinct OxPC in rat kidney following I/R injury. These included a variety of fragmented (aldehyde and carboxylic acid containing species) and non-fragmented products. 1-stearoyl-2-linoleoyl-phosphatidylcholine (SLPC-OH), which is a non-fragmented OxPC and 1-palmitoyl-2-azelaoyl-sn-glycero-3-phosphocholine (PAzPC), which is a fragmented OxPC, were the most abundant OxPC species after 6h and 24 h I/R respectively. Total fragmented aldehyde OxPC were significantly higher in 6h and 24h I/R groups compared to sham operated groups (P = 0.03, 0.001 respectively). Moreover, levels of aldehyde OxPC at 24h I/R were significantly greater than those in 6h I/R (P = 0.007). Fragmented carboxylic acid increased significantly in 24h I/R group compared with sham and 6h I/R groups (P = 0.001, 0.001). Moreover, levels of fragmented OxPC were significantly correlated with creatinine levels (r = 0.885, P = 0.001). Among non-fragmented OxPC, only isoprostanes were elevated significantly in 6h I/R group compared with sham group but not in 24h I/R group (P = 0.01). No significant changes were observed in other non-fragmented OxPC including long chain products and terminal furans. Conclusion We have shown for the first time that bioactive OxPC species are produced in renal I/R and their levels increase with increasing time of reperfusion in a kidney model of I/R and correlate with severity of I/R injury. Given the pathological activity of fragmented OxPCs, therapies focused on their reduction may be a mechanism to attenuate renal I/R injury.

Folic Acid Supplementation Attenuates Chronic Hepatic Inflammation in High-Fat Diet Fed Mice

Nonalcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease worldwide. Hepatic inflammation is an important pathogenic mediator of NAFLD. There is currently no pharmacological agent approved for the treatment of NAFLD. Folic acid is a water-soluble B vitamin that has been shown to have lipid-lowering and antioxidant effects. The objective of this study was to investigate the effect of folic acid supplementation on hepatic inflammation and to identify the underlying mechanisms. Male C57BL/6 J mice were fed a control diet (10% kcal fat), a high-fat diet (HFD) (60% kcal fat), or a HFD supplemented with folic acid (26 mg/kg diet) for 8 weeks. HFD feeding led to increased body mass gain, lipid accumulation, activation of transcription factor nuclear factor-κB (NF-κB), and elevation of inflammatory cytokine gene expression in the liver. Folic acid supplementation attenuated hepatic lipid accumulation and aggregation of inflammatory foci induced by HFD feeding. This was associated with a significant reduction of NF-κB activation and inflammatory cytokine expression. These results suggest that the hepatoprotective effect of folic acid in NAFLD may be attributed, in part, to its anti-inflammatory action.

Chicken Gut Microbiota: Importance and Detection Technology

Sustainable poultry meat and egg production is important to provide safe and quality protein sources in human nutrition worldwide. The gastrointestinal (GI) tract of chickens harbor a diverse and complex microbiota that plays a vital role in digestion and absorption of nutrients, immune system development and pathogen exclusion. However, the integrity, functionality, and health of the chicken gut depends on many factors including the environment, feed, and the GI microbiota. The symbiotic interactions between host and microbe is fundamental to poultry health and production. The diversity of the chicken GI microbiota is largely influenced by the age of the birds, location in the digestive tract and diet. Until recently, research on the poultry GI microbiota relied on conventional microbiological techniques that can only culture a small proportion of the complex community comprising the GI microbiota. 16S rRNA based next generation sequencing is a powerful tool to investigate the biological and ecological roles of the GI microbiota in chicken. Although several challenges remain in understanding the chicken GI microbiome, optimizing the taxonomic composition and biochemical functions of the GI microbiome is an attainable goal in the post-genomic era. This article reviews the current knowledge on the chicken GI function and factors that influence the diversity of gut microbiota. Further, this review compares past and current approaches that are used in chicken GI microbiota research. A better understanding of the chicken gut function and microbiology will provide us new opportunities for the improvement of poultry health and production.