Apelin-13: a novel approach to suppressing renin production in RVHT.

Renovascular hypertension (RVHT) is characterized by renal artery stenosis and overactivated renin-angiotensin system (RAS). Apelin, known for its negative modulation of RAS, has protective effects against cardiovascular diseases. The role and mechanisms of the primary active form of apelin, apelin-13, in RVHT are unclear. In this study, male Sprague-Dawley rats were divided into control, two-kidney one-clip (2K1C) model, and 2K1C with apelin-13 treatment groups. Renin expression was analyzed using immunohistochemistry and molecular techniques. Full-length (pro)renin receptor (fPRR) and soluble PRR (sPRR) levels were assessed via Western blotting, and cAMP levels were measured using ELISA. Plasma renin content, plasma renin activity (PRA), angiotensin II (ANG II), and sPRR levels were determined by ELISA. Human Calu-6 and mouse As4.1 cells were used to investigate renin production mechanisms. The 2K1C model exhibited increased systolic blood pressure, plasma renin content, PRA, sPRR, and ANG II levels, while apelin-13 treatment reduced these elevations. Apelin-13 inhibited cAMP production, renin mRNA expression, protein synthesis, and PRR/sPRR protein expression in renal tissue. In Calu-6 cells, cAMP-induced fPRR and site-1 protease (S1P)-derived sPRR expression, which was blocked by cAMP-responsive element-binding protein (CREB) inhibition. Apelin-13 suppressed cAMP elevation, CREB phosphorylation, fPRR/sPRR protein expression, and renin production. Recombinant sPRR (sPRR-His) stimulated renin production, which was inhibited by the PRR decoy peptide PRO20 and S1P inhibitor PF429242. These findings suggest that apelin-13 inhibits plasma renin expression through the cAMP/PKA/sPRR pathway, providing a potential therapeutic approach for RVHT. Understanding the regulation of renin production is crucial for developing effective treatments.NEW & NOTEWORTHY Our research elucidated that apelin-13 inhibits renin production through the cAMP/PKA/soluble (pro)renin receptor pathway, presenting a promising therapeutic approach for renovascular hypertension (RVHT) by targeting renin expression mechanisms. These findings underscore the potential of apelin-13 as a novel strategy to address RVHT.

Utilizing Ultra-homogeneous SiOx and Defects to Achieve Interlayer Protection for Lithium Metal Anodes.

The uncontrollable growth and uneven nucleation of lithium metal can be addressed by utilizing spatial confinement structures in conjunction with lithiophilic sites. However, their complex fabrication technique and the inhomogeneous dispersion of lithiophilic sites make the application ineffective. In this work, ultra-uniformly dispersed SiOx seeds and defects are produced in situ to achieve the spatially restricted protection within the reduced graphene oxide (rGO) layer. The in situ formed SiOx and defects during annealing double constrain lithium nucleation and growth behaviors thanks to the superlithiophilic characteristic, while both provide the fast Li+ transport channel to utilize the interlayer protection of rGO in limiting lithium dendrite growth. Furthermore, XANES and XPS analyze the SiOx seeds that are dominated by various valence states, and theoretical calculations further verify the control on the nucleation of lithium atoms. Benefiting from the optimum average valence of three for the "control site", the host realizes steady circulation. In asymmetric cells, the host demonstrates excellent coulombic efficiency of 99.1% and stable lifespans over 1250 h at 1 mA cm-2 . When assembled in LiFePO4 full cells, it retains a favorable capacity of 116.2 mA h g-1 after 170 cycles.

Strategies and challenges of carbon materials in the practical applications of lithium metal anode: a review.

Lithium (Li) metal is strongly considered to be the ultimate anode for next-generation high-energy-density rechargeable batteries due to its lowest electrochemical potential and highest specific capacity. However, Li metal anode has limitations, involving inevitable dendritic Li growth, nonuniform Li deposition, enormous volume expansion, and ultimate electrode pulverization, which lead to rapid decrease in Coulombic efficiency and short circuits, significantly hindering its practical use. Various strategies have been proposed to solve uncontrollable dendritic Li growth and parasitic electrochemical reactions. Carbon materials and their composites with excellent structure tunability and properties have been explored to solve these issues and have shown great potential applications in Li metal anodes. This review presents various protective strategies of Li metal anode based on carbon materials. The rational design of carbon materials with specific functionalities in Li metal anode protecting solutions and manufacturing methods of composite electrodes with metallic Li and carbon materials are discussed in detail. In addition, a comprehensive understanding of the challenges and our outlook on the future development of carbon materials for stabilizing Li metal anodes in practical applications are discussed and prospected.

Effects of fermented unconventional protein feed on pig production in China.

Unconventional protein feeds, characterized by low nutritional value, high variability, and poor palatability, have limited their application in swine production. Fermentation technology holds the key to addressing these shortcomings. Given the ban on antibiotics in China, the inferior quality of imported pig breeds, and long-term dependence on imported soybean, the prospects for fermented unconventional protein feeds are promising. This paper delves into the common types of fermented unconventional protein feeds, factors influencing the fermentation process, the mechanisms by which they enhance swine health, and the challenges and prospects of fermented feeds, offering theoretical insights for the future development of the feed industry.

One-Step Construction of Closed Pores Enabling High Plateau Capacity Hard Carbon Anodes for Sodium-Ion Batteries: Closed-Pore Formation and Energy Storage Mechanisms.

Closed pores play a crucial role in improving the low-voltage (<0.1 V) plateau capacity of hard carbon anodes for sodium-ion batteries (SIBs). However, the lack of simple and effective closed-pore construction strategies, as well as the unclear closed-pore formation mechanism, has severely hindered the development of high plateau capacity hard carbon anodes. Herein, we present an effective closed-pore construction strategy by one-step pyrolysis of zinc gluconate (ZG) and elucidate the corresponding mechanism of closed-pore formation. The closed-pore formation mechanism during the pyrolysis of ZG mainly involves (i) the precipitation of ZnO nanoparticles and the ZnO etching on carbon under 1100 °C to generate open pores of 0.45-4 nm and (ii) the development of graphitic domains and the shrinkage of the partial open pores at 1100-1500 °C to convert the open pores to closed pores. Benefiting from the considerable closed-pore content and suitable microstructure, the optimized hard carbon achieves an ultrahigh reversible specific capacity of 481.5 mA h g-1 and an extraordinary plateau capacity of 389 mA h g-1 for use as the anode of SIBs. Additionally, some in situ and ex situ characterizations demonstrate that the high-voltage slope capacity and the low-voltage plateau capacity stem from the adsorption of Na+ at the defect sites and Na-cluster formation in closed pores, respectively.

A Review of the Relationship between Gel Polymer Electrolytes and Solid Electrolyte Interfaces in Lithium Metal Batteries.

Lithium metal batteries (LMBs) are a dazzling star in electrochemical energy storage thanks to their high energy density and low redox potential. However, LMBs have a deadly lithium dendrite problem. Among the various methods for inhibiting lithium dendrites, gel polymer electrolytes (GPEs) possess the advantages of good interfacial compatibility, similar ionic conductivity to liquid electrolytes, and better interfacial tension. In recent years, there have been many reviews of GPEs, but few papers discussed the relationship between GPEs and solid electrolyte interfaces (SEIs). In this review, the mechanisms and advantages of GPEs in inhibiting lithium dendrites are first reviewed. Then, the relationship between GPEs and SEIs is examined. In addition, the effects of GPE preparation methods, plasticizer selections, polymer substrates, and additives on the SEI layer are summarized. Finally, the challenges of using GPEs and SEIs in dendrite suppression are listed and a perspective on GPEs and SEIs is considered.

Whole genome sequencing and analysis of selenite-reducing bacteria Bacillus paralicheniformis SR14 in response to different sugar supplements.

The biosynthetic process of selenium nanoparticles (SeNPs) by specific bacterial strain, whose growth directly affects the synthesis efficiency, has attracted great attentions. We previously reported that Bacillus paralicheniformis SR14, a SeNPs-producing bacteria, could improve intestinal antioxidative function in vitro. To further analyze the biological characteristics of SR14, whole genome sequencing was used to reveal the genetic characteristics in selenite reduction and sugar utilization. The results reviewed that the genome size of SR14 was 4,448,062 bp, with a GC content of 45.95%. A total of 4300 genes into 49 biological pathways was annotated to the KEGG database. EC: 1.1.1.49 (glucose-6-phosphate 1-dehydrogenase) and EC: 5.3.1.9 (glucose-6-phosphate isomerase), were found to play a potential role in glucose degradation and EC:2.7.1.4 (fructokinase) might be involved in the fructose metabolism. Growth profile and selenite-reducing ability of SR14 under different sugar supplements were determined and the results reviewed that glucose had a better promoting effect on the reduction of selenite and growth of bacteria than fructose, sucrose, and maltose. Moreover, RT-qPCR experiment proved that glucose supplement remarkably promoted the expressions of thioredoxin, fumarate reductase, and the glutathione peroxidase in SR14. Analysis of mRNA expression showed levels of glucose-6-phosphate dehydrogenase and fructokinase significantly upregulated under the supplement of glucose. Overall, our data demonstrated the genomic characteristics of SR14 and preliminarily determined that glucose supplement was most beneficial for strain growth and SeNPs synthesis.

Modulation of Si-O Structure in Uniformly Ultrasmall Silicon Oxycarbide for Superior Lifespan of Lithium Metal Anodes.

Utilizing nanoseeds guiding homogeneous deposition of lithium is an effective strategy to inhibit disorderly growth of lithium, where silicon oxide has been attracting attention as a transform seed. However, the research on silicon-oxide-based seeds has concentrated more on utilizing their lithiophilicity but less on their Si-O structures, which could result in different failure mechanisms. In this study, various Si-O structures of silicon oxycarbide carbon nanofibers are prepared by adjusting the content of octa(aminopropylsilsesquioxane). According to XANES and experimental observations, the C-rich SiOC has an active Si-O-C structure but generates a larger volume variation during lithiation, while in the O-rich phase, the silica-oxygen tetrahedral structure can contribute to alleviate the volume expansion but has poor electrochemical activity. SiOC, which is dominated by SiO3C, has a suitable Si-O and silica-oxygen tetrahedral-structure distribution, which balances the electrochemical activity and volume expansion. This allows the host to demonstrate an excellent lifespan over 3740 h with a tiny voltage hysteresis (22 mV) at 2 mA cm-2, and it retains a favorable capacity of 97 mA h g-1 after 630 cycles with a high Coulombic efficiency of 99.7% in full cells. This study experiences the influence of various Si-O structures on lithium metal anodes.

Integrated rumen microbiome and serum metabolome analysis responses to feed type that contribution to meat quality in lambs.

BACKGROUND: Lifestyle factors, such as diet, are known to be a driver on the meat quality, rumen microbiome and serum metabolites. Rumen microbiome metabolites may be important for host health, the correlation between rumen microbiome and production of rumen metabolites are reported, while the impact of rumen microbiome on the serum metabolome and fatty acid of meat are still unclear. This study was designed to explore the rumen microbiome, serum metabolome and fatty acid of meat in response to the grass diet and concentrate diet to lambs, and the relationship of which also investigated. METHODS: In the present study, 12 lambs were randomly divided into two groups: a grass diet (G) and a concentrate diet (C). Here, multiple physicochemical analyses combined with 16S rRNA gene sequences and metabolome analysis was performed to reveal the changes that in response to feed types. RESULTS: The concentrate diet could improve the growth performance of lambs compared to that fed with the grass diet. The microbiome composition was highly individual, compared to the concentrate group, the abundance of Rikenellaceae_RC9_gut_group, F082_unclassified, Muribaculaceae_unclassified, Ruminococcaceae_NK4A214_group, Bacteroidetes_unclassified, and Bacteroidales_UCG-001_unclassified were significantly (P < 0.05) lower in the grass group, while, the abundance of Succinivibrio, Succinivibrionaceae_UCG-002, Fibrobacter and Christensenellaceae_R-7_group were significantly (P < 0.05) higher in the grass group. Serum metabolomics analysis combined with enrichment analysis revealed that serum metabolites were influenced by feed type as well as the metabolic pathway, and significantly affected serum metabolites involved in amino acids, peptides, and analogues, bile acids, alcohols and derivatives, linoleic acids derivatives, fatty acids and conjugates. Most of the amino acids, peptides, and analogues metabolites were positively associated with the fatty acid contents. Among the bile acids, alcohols and derivatives metabolites, glycocholic was positively associated with all fatty acid contents, except C18:0, while 25-Hydroxycholesterol and lithocholic acid metabolites were negatively associated with most of the fatty acid contents. CONCLUSION: Correlation analysis of the association of microbiome with metabolite features, metabolite features with fatty acid provides us with comprehensive understanding of the composition and function of microbial communities. Associations between utilization or production were widely identified among affected microbiome, metabolites and fatty acid, and these findings will contribute to the direction of future research in lamb.

Gut-targeted nanoparticles deliver specifically targeted antimicrobial peptides against Clostridium perfringens infections.

Specifically targeted antimicrobial peptides (STAMPs) are novel alternatives to antibiotics, whereas the development of STAMPs for colonic infections is hindered by limited de novo design efficiency and colonic bioavailability. In this study, we report an efficient de novo STAMP design strategy that combines a traversal design, machine learning model, and phage display technology to identify STAMPs against Clostridium perfringens. STAMPs could physically damage C. perfringens, eliminate biofilms, and self-assemble into nanoparticles to entrap pathogens. Further, a gut-targeted engineering particle vaccine (EPV) was used for STAMPs delivery. In vivo studies showed that both STAMP and EPV@STAMP effectively limited C. perfringens infections and then reduced inflammatory response. Notably, EPV@STAMP exhibited stronger protection against colonic infections than STAMPs alone. Moreover, 16S ribosomal RNA sequencing showed that both STAMPs and EPV@STAMP facilitated the recovery of disturbed gut microflora. Collectively, our work may accelerate the development of the discovery and delivery of precise antimicrobials.

Interfacial Anchored Sesame Ball-like Ag/C To Guide Lithium Even Plating and Stripping Behavior.

Lithium (Li) metal is a candidate anode for the next generation of high-energy density secondary batteries. Unfortunately, Li metal anodes (LMAs) are extremely reactive with electrolytes to accumulate uncontrolled dendrites and to generate unwanted parasitic electrochemical reactions. Much attention has been focused on carbon materials to address these issues. Ulteriorly, the failure mechanism investigation of lithiophilic sites on carbon materials has been not taken seriously. Herein, we design a new type of sesame ball-like carbon sphere (AgNPs@CS, an average diameter of ∼700 nm) with uniformly interfacial anchored silver nanoparticles (AgNPs), which is used as the dendrite-free Li metal anode host. This anchored structure significantly enhances reversible and chemical affinity of Li, effectively inhibiting "dead Li". In addition, the protective effect of the carbon layer can avoid the damage of lithiophilic AgNPs in the carbon matrix. With a plating/striping capacity of 2 mA h cm-2, the AgNPs@CS electrode can be cycled over 2400 h at 0.5 mA cm-2. When the stripping voltage increases to 1 V, the AgNPs@CS electrode also enables excellent cycling stability to achieve over 260 cycles (1 mA cm-2, 1 mA h cm-2) and 130 cycles (2 mA cm-2, 1 mA h cm-2). This material by electrochemical characterization highlights the efficacy of this facile method for developing dendrite-free LMAs.

Bacillus amyloliquefaciens 40 regulates piglet performance, antioxidant capacity, immune status and gut microbiota.

Probiotics can improve animal growth performance and intestinal health. Bacillus species, Lactobacillus species, Bifidobacterium species, yeast etc. are the common types of probiotics. However, understanding the effects of probiotics on the immune status and gut microbiota of weaning piglets and how the probiotics exert their impact are still limited. This study aimed to investigate the effects of Bacillus amyloliquefaciens 40 (BA40) on the performance, immune status and gut microbiota of piglets. A total of 12 litters of newborn piglets were randomly divided into 3 groups. Piglets in control group were orally dosed with phosphate buffered saline; BA40 group and probiotics group were orally gavaged with resuspension BA40 and a probiotics product, respectively. The results showed that BA40 treatment significantly decreased (P < 0.05) the diarrhea incidence (from d 5 to 40), diamine oxidase, D-lactate, interleukin (IL)-1ß and interferon-γ concentrations compared with control group and probiotics group. Meanwhile BA40 dramatically increased the total antioxidant capacity, IL-10 and secretory immunoglobulin-A concentrations in contrast to control group. For the microbial composition, BA40 modulated the microbiota by improving the abundance of Bacteroides, Phascolarctobacterium (producing short-chain fatty acids) and Desulfovibrio and reducing the proliferation of pathogens (Streptococcus, Tyzzerella, Vellionella and paraeggerthella). Meanwhile, a metabolic function prediction explained that carbohydrate metabolism and amino acid metabolism enriched in BA40 group in contrast to control group and probiotics group. For correlation analysis, the results demonstrated that BA40-enriched Phascolarctobacterium and Desulfovibrio provide insights into strategies for elevating the health status and performance of weaned piglets. Altogether, BA40 exerted stronger ability in decreasing diarrhea incidence and improved antioxidant activity, gut barrier function and immune status of piglets than the other treatments. Our study provided the experimental and theoretical basis for the application of BA40 in pig production.

The Role of Probiotics in Alleviating Postweaning Diarrhea in Piglets From the Perspective of Intestinal Barriers.

Early weaning of piglets is an important strategy for improving the production efficiency of sows in modern intensive farming systems. However, due to multiple stressors such as physiological, environmental and social challenges, postweaning syndrome in piglets often occurs during early weaning period, and postweaning diarrhea (PWD) is a serious threat to piglet health, resulting in high mortality. Early weaning disrupts the intestinal barrier function of piglets, disturbs the homeostasis of gut microbiota, and destroys the intestinal chemical, mechanical and immunological barriers, which is one of the main causes of PWD in piglets. The traditional method of preventing PWD is to supplement piglet diet with antibiotics. However, the long-term overuse of antibiotics led to bacterial resistance, and antibiotics residues in animal products, threatening human health while causing dysbiosis of gut microbiota and superinfection of piglets. Antibiotic supplementation in livestock diets is prohibited in many countries and regions. Regarding this context, finding antibiotic alternatives to maintain piglet health at the critical weaning period becomes a real emergency. More and more studies showed that probiotics can prevent and treat PWD by regulating the intestinal barriers in recent years. Here, we review the research status of PWD-preventing and treating probiotics and discuss its potential mechanisms from the perspective of intestinal barriers (the intestinal microbial barrier, the intestinal chemical barrier, the intestinal mechanical barrier and the intestinal immunological barrier) in piglets.

Lithiophilic onion-like carbon spheres as lithium metal uniform deposition host.

Lithium metal is considered as a promising anode material for next-generation secondary batteries, owing to its high theoretical specific capacity (3860 mA h g-1). Nevertheless, the practical application of Li in lithium metal batteries (LMBs) is hampered by inhomogeneous Li deposition and irreversible "dead Li", which lead to low coulombic efficiency (CE) and safe hazards. Designing unique lithiophilic structure is an efficient strategy to control Li uniformly plating /stripping. Here, we report the silver (Ag) nanoparticles coated with nitrogen-doped onion-like carbon microspheres (Ag@NCS) as a host to reduce the nucleation overpotential of Li for dendrite-free LBMs. The Ag@NCS were prepared by a simple one-step injection pyrolysis. The lithiophilic Ag is demonstrated to be priority selective deposition of Li in the carbon cage. Meanwhile, the onion-like structure benefits to uniform lithium nucleation and dendrite-free lithium during cycling. Impressively, we successfully captured lithium metal on different hosts at atomic scale, further proving that Ag@NCS can effectively and uniformly deposit Li. Besides, Ag@NCS show a superiorly electrochemical performance with a low nucleation overpotential (∼1 mV), high CE and stable cycling performance (over 400 cycles at 0.5 mA cm-2) compared to the Ag-free onion-like carbon in LMBs. Even under harsh conditions (1 mA cm-2, 4 mA h cm-2), Ag@NCS still present superior cycling stability for more than 150 cycles. Furthermore, a full cell composed of LiFePO4 cathode exhibits significantly improved voltage hysteresis with low voltage polarization. This work provides a new choice and route for the design and preparation of lithiophilic host materials.

Screening of Tobacco Genotypes for Phytophthora nicotianae Resistance.

Black shank, caused by the oomycetes Phytophthora nicotianae, is destructive to tobacco, and this pathogen is highly pathogenic to many solanaceous crops. P. nicotianae is well adapted to high temperatures; therefore, research on this pathogen is gaining importance in agriculture worldwide because of global warming. P. nicotianae-resistant varieties of tobacco plants are commonly screened by inoculation with oat grains colonized by P. nicotianae and monitoring for the disease symptoms. However, it is difficult to quantify the inoculation intensity since accurate inoculation is crucial in this case. This study aimed to develop an efficient and reliable method for evaluating the resistance of tobacco to infection with P. nicotianae. This method has been successfully used to identify resistant varieties, and the inoculation efficiency was confirmed by real-time PCR. The resistance evaluation method presented in this study is efficient and practical for precision breeding, as well as molecular mechanism research.

Dynamics of defatted rice bran in physicochemical characteristics, microbiota and metabolic functions during two-stage co-fermentation.

Defatted rice bran (DFRB) is an inexpensive and easily available agricultural byproduct. Existence of anti-nutritional factors (ANFs), high fiber and low protein content, susceptible to oxidation and rancidity make DFRB currently underutilized. In this study, Bacillus subtilis with high enzyme activities, Saccharomyces cerevisiae with high single-cell proteins concentration and Lactiplantibacillus plantarum with excellent acid secreting capacity were screened to co-fermented DFRB with phytase, and multiple physicochemical analyses combined with high-throughput sequencing were applied to provide insights into the dynamics of the physicochemical characteristics and the complex microbiome during the two-stage co-fermentation of DFRB. The results showed that co-fermentation effectively improved the nutritional value by degrading ANFs (trypsin inhibitors and phytic acid), fiber (acid detergent fiber and neutral detergent fiber) and allergenic protein, and increasing the trichloroacetic acid soluble protein, amino acids and organic acid. In addition, co-fermentation prevented lipid oxidation by enhancing antioxidant activity and reducing the activity of lipase and lipoxygenase. High-throughput sequencing results suggested that co-fermentation optimized microbial community of DFRB by increasing desirable Lactobacillus, Pediococcus, Saccharomyces and Talaromyces and reducing undesirable bacteria (Enterobacter and Pseudomonas) and animal and plant-pathogenic fungi (Blumeria, Alternaria, Fusarium, etc.). Furthermore, high-throughput sequencing and gas chromatography-mass spectrometry (GC-MS) were adopted to predict microbial metabolic functions and metabolic pathways during whole DFRB co-fermentation.

Co-fermented yellow wine lees by Bacillus subtilis and Enterococcus faecium regulates growth performance and gut microbiota in finishing pigs.

Fermented yellow wine lees (FYWL) are widely used to increase feed utilization and improve pig performance. Based on the preparation of co-FYWL using Bacillus subtilis and Enterococcus faecalis, the purpose of this study was to investigate the effects of co-FYWL on growth performance, gut microbiota, meat quality, and immune status of finishing pigs. 75 pigs were randomized to 3 treatments (5 replicates/treatment), basal diet (Control), a basal diet supplemented with 4%FYWL, and a basal diet supplemented with 8%FYWL, for 50 days each. Results showed that the 8% FYWL group significantly reduced the F/G and increased the average daily weight gain of pigs compared to the control group. In addition, 8% FYWL improved the richness of Lactobacillus and B. subtilis in the gut, which correlated with growth performance, serum immune parameters, and meat quality. Furthermore, acetate and butyrate in the feces were improved in the FYWL group. Simultaneously, FYWL improved the volatile flavor substances of meat, increased the content of flavor amino acids, and played a positive role in the palatability of meat. In addition, FYWL increased serum IgA, IgM, IL-4 and IL-10 levels. Overall, the growth performance, the gut microbiota associated with fiber degradation, meat quality, and immune status were improved in the 8% FYWL group.

Co-fermented defatted rice bran alters gut microbiota and improves growth performance, antioxidant capacity, immune status and intestinal permeability of finishing pigs.

Based on preparation of co-fermented defatted rice bran (DFRB) using Bacillus subtilis, Saccharomyces cerevisiae, Lactobacillus plantarum and phytase, the present study aimed to evaluate the effects of co-fermented DFRB on growth performance, antioxidant capacity, immune status, gut microbiota and permeability in finishing pigs. Ninety finishing pigs (85.30 ± 0.97 kg) were randomly assigned to 3 treatments (3 replicates/treatment) with a basal diet (Ctrl), a basal diet supplemented with 10% unfermented DFRB (UFR), and a basal diet supplemented with 10% fermented DFRB (FR) for 30 d. Results revealed that the diet supplemented with FR notably (P < 0.05) improved the average daily gain (ADG), gain to feed ratio (G:F) and the digestibility of crude protein, amino acids and dietary fiber of finishing pigs compared with UFR. Additionally, FR supplementation significantly (P < 0.05) increased total antioxidant capacity, the activities of superoxide dismutase and catalase, and decreased the content of malonaldehyde in serum. Furthermore, FR remarkably (P < 0.05) increased serum levels of IgG, anti-inflammatory cytokines (IL-22 and IL-23) and reduced pro-inflammatory cytokines (TNF-α, IL-1ß and INF-γ). The decrease of serum diamine oxidase activity and serum D-lactate content in the FR group (P < 0.05) suggested an improvement in intestinal permeability. Supplementation of FR also elevated the content of acetate and butyrate in feces (P < 0.05). Moreover, FR enhanced gut microbial richness and the abundance of fiber-degrading bacteria such as Clostridium butyricum and Lactobacillus amylovorus. Correlation analyses indicated dietary fiber in FR was associated with improvements in immune status, intestinal permeability and the level of butyrate-producing microbe C. butyricum, which was also verified by the in vitro fermentation analysis. These findings provided an experimental and theoretical basis for the application of fermented DFRB in finishing pigs.

Bifidobacterium longum, Lactobacillus plantarum and Pediococcus acidilactici Reversed ETEC-Inducing Intestinal Inflammation in Mice.

Microecological preparation could relieve Enterotoxigenic Escherichia coli (ETEC) K88-induced diarrhea in piglets, but which bacteria play a key role and the mitigation mechanism have not been fully clarified. In this study, 36 male mice were randomly divided into six groups (CON, K88, BK (Bifidobacterium longum + K88), LK (Lactobacillus plantarum + K88), PK (Pediococcus acidilactici + K88), and MK (mixed strains + K88)) to explore the prevention mechanisms. Three probiotic strains and their mixtures (TPSM) significantly relieved the weight loss and restored the ratio of villus height to crypt depth in the jejunum. Except for Bifidobacterium longum, other strains significantly decreased interleukin (IL)-1ß, IL-6 and tumor necrosis factor-α (TNF-α) in mice serum. The TPSM treatment significantly downregulated the mRNA expression of the inflammatory cytokines and the Toll-like receptor and downstream gene (TLR4, MyD88, NF-κB) in jejunum induced by ETEC. Furthermore, the TPSM could restore dysbiosis of the intestinal microbiota caused by ETEC. The intestinal microbiota analysis demonstrated that Bifidobacterium longum enriched the Bifidobacterium genus (p < 0.05), Lactobacillus plantarum enriched the Lactobacillus genus (p < 0.05), Pediococcus acidilactici enriched the Coriobacteriaceae_UCG-002 and Christensenellaceae_R-7_group genus (p < 0.05), mixed bacteria enriched the Akkermansia genus (p < 0.05), but ETEC enriched the Desulfovibrio genus (p < 0.05). Meanwhile, the starch and sucrose metabolism, galactose and fructose metabolism, mannose metabolism and ABC transporters were increased with probiotics pre-treatment (p < 0.05). To sum up, the microecological preparation alleviated ETEC-induced diarrhea by regulating the immune response, rebalancing intestinal microbiota and improving carbohydrate metabolism.

Effect of Porcine Clostridium perfringens on Intestinal Barrier, Immunity, and Quantitative Analysis of Intestinal Bacterial Communities in Mice.

Clostridium perfringens (C. perfringens) is one of the main pathogens which can cause a range of histotoxic and enteric diseases in humans or animals (pigs, or broilers). The Centers for Disease Control and Prevention (CDC) estimates these bacteria cause nearly 1 million illnesses in the United States every year. For animal husbandry, necrotizing enteritis caused by C. perfringens can cost the global livestock industry between $2 billion and $6 billion per year. C. perfringens-infected animals can be isolated for its identification and pathology. A suitable animal model is one of the essential conditions for studying the disease pathogenesis. In previous studies, mice have been used as subjects for a variety of Clostridium perfringens toxicity tests. Thus, this study was designed to build a mouse model infected porcine C. perfringens which was isolated from the C.perfringens-infected pigs. A total of 32 6-week-old male C57BL/6 mice were randomly divided into four groups. Control group was orally administrated with PBS (200 µL) on day 0. Low group, Medium group, and High group were gavaged with 200 ul of PBS resuspension containing 8.0 × 107 CFU, 4.0 × 108 CFU, and 2.0 × 109 CFU, respectively. We examined growth performance, immune status, intestinal barrier integrity, apoptosis-related genes expression, and copies of C. perfringens in mice. The results showed that the growth performance declined and intestinal structure was seriously damaged in High group. Meanwhile, pro-inflammatory factors (IL-1ß, TNF-α, and IL-6) were significantly increased (P < 0.05) in High group compared to other groups. The tight junctions and pro-apoptosis related genes' expression significantly decreased (P < 0.05) in High group, and high dose caused a disruption of intestinal villi integrity and tissue injury in the jejunum of mice. In addition, the enumerations of C. perfringens, Escherichia coli, and Lactobacillus explained why the gut of High group mice was seriously damaged, because the C. perfringens and Escherichia coli significantly enriched (P < 0.05), and Lactobacillus dramatically decreased (P < 0.05). Overall, our results provide an experimental and theoretical basis for understanding the pathogenesis and exploring the effects of porcine C. perfringens on mice.