Evaluation of probiotic properties of a Brevibacillus laterosporus strain.

Brevibacillus laterosporus is a strain of probiotic bacteria that has been widely used in pest control, cash crop, and other production areas. However, few studies have been conducted on its use as a feed additive in animals. Therefore, the probiotic potential of B. laterosporus PBC01 was evaluated by characterizing hydrophobicity, auto-aggregation activity, bile salt and simulated gastrointestinal fluid tolerance, bienzymatic, and antibacterial activity. Antibiotic susceptibility, hemolysis assays, and supplemental feeding of mice were also performed to evaluate safety features. Our results showed that B. laterosporus PBC01 had moderate hydrophobicity, high auto-agglutination ability. Meanwhile, B. laterosporus PBC01 had good tolerance to bile salt and simulated gastrointestinal fluid. It had the ability to secrete protease, cellulase, and to inhibit various pathogens. In addition, B. laterosporus PBC01 was sensitive to many antibiotics, and did not produce hemolysin. In the safety assessment of mice, it did not cause any deaths, nor did it affect the cell components of blood, antioxidant capacity, and reproductive health. The study indicated the great probiotic characteristics and safety of B. laterosporus PBC01. This may provide a theoretical basis for the clinical application and development of probiotic-based feed additives.

Fluoride exposure-induced gut microbiota alteration mediates colonic ferroptosis through N6-methyladenosine (m6A) mediated silencing of SLC7A11.

Fluoride exposure is widespread worldwide and poses a significant threat to organisms, particularly to their gastrointestinal tracts. However, due to limited knowledge of the mechanism of fluoride induced intestinal injury, it has been challenging to develop an effective treatment. To address this issue, we used a series of molecular biology in vitro and in vivo experiments. NaF triggered m6A mediated ferroptosis to cause intestinal damage. Mechanistically, NaF exposure increased the m6A level of SLC7A11 mRNA, promoted YTHDF2 binding to m6A-modified SLC7A11 mRNA, drove the degradation of SLC7A11 mRNA, and led to a decrease in its protein expression, which eventually triggers ferroptosis. Moreover, NaF aggravated ferroptosis of the colon after antibiotics destroyed the composition of gut microbiota. 16 S rRNA sequencing and SPEC-OCCU plots, Zi-Pi relationships, and Spearman correlation coefficients verified that Lactobacillus murinus (ASV54, ASV58, and ASV82) plays a key role in the response to NaF-induced ferroptosis. Collectively, NaF-induced gut microbiota alteration mediates severe intestinal cell injury by inducing m6A modification-mediated ferroptosis. Our results highlight a key mechanism of the gut in response to NaF exposure and suggest a valuable theoretical basis for its prevention and treatment.

The panda-derived Lactiplantibacillus plantarum BSG201683 improves LPS-induced intestinal inflammation and epithelial barrier disruption in vitro.

Captive pandas are suffering from intestinal infection due to intestinal microbiota characterized by a high abundance of Enterobacteriaceae induced by long-term captivity. Probiotic supplements showed improvement in intestinal barrier function and inflammation. However, the effects of panda-derived probiotics on the intestinal epithelium and inflammation have not been elucidated. In the present study, lipopolysaccharide (LPS) impaired Caco-2 and RAW264.7 inflammatory models were applied to assess the protection of Lactiplantibacillus plantarum BSG201683 (L. plantarum G83) on barrier disruption and inflammation. The results showed that treatment with L. plantarum G83 significantly decreased the paracellular permeability to fluorescein isothiocyanate conjugated dextran (MW 4000, FITC-D4) after LPS induction. Meanwhile, L. plantarum G83 alleviated the reduction in tight junction (TJ) proteins and downregulated proinflammatory cytokines caused by LPS in Caco-2 cells. L. plantarum G83 also significantly decreased the expression and secretion of pro-inflammatory cytokines in LPS-induced RAW264.7 cells. In addition, the IL-10 increased in both Caco-2 and RAW264.7 cells after L. plantarum G83 treatment. The phagocytosis activity of RAW264.7 cells was significantly increased after L. plantarum G83 treatment. Toll-like receptor 4/ nuclear factor kappa-B (TLR4/NF-κB) signaling pathways were significantly down-regulated after L. plantarum G83 intervention, and the phosphorylation of NF-κB/p65 was consistent with this result. Our findings suggest that L. plantarum G83 improves intestinal inflammation and epithelial barrier disruption in vitro.

Fluoride disrupts intestinal epithelial tight junction integrity through intracellular calcium-mediated RhoA/ROCK signaling and myosin light chain kinase.

Fluoride is a common contaminant of groundwater and agricultural commodity, which poses challenges to animal and human health. A wealth of research has demonstrated its detrimental effects on intestinal mucosal integrity; however, the underlying mechanisms remain obscure. This study aimed to investigate the role of the cytoskeleton in fluoride-induced barrier dysfunction. After sodium fluoride (NaF) treatment of the cultured Caco-2 cells, both cytotoxicity and cytomorphological changes (internal vacuoles or massive ablation) were observed. NaF lowered transepithelial electrical resistance (TEER) and enhanced paracellular permeation of fluorescein isothiocyanate dextran 4 (FD-4), indicating Caco-2 monolayers hyperpermeability. In the meantime, NaF treatment altered both the expression and distribution of the tight junction protein ZO-1. Fluoride exposure increased myosin light chain II (MLC2) phosphorylation and triggered actin filament (F-actin) remodeling. While inhibition of myosin II by Blebbistatin blocked NaF-induced barrier failure and ZO-1 discontinuity, the corresponding agonist Ionomycin had effects comparable to those of fluoride, suggesting that MLC2 serves as an effector. Given the mechanisms upstream of p-MLC2 regulation, further studies demonstrated that NaF activated RhoA/ROCK signaling pathway and myosin light chain kinase (MLCK), strikingly increasing the expression of both. Pharmacological inhibitors (Rhosin, Y-27632 and ML-7) reversed NaF-induced barrier breakdown and stress fiber formation. The role of intracellular calcium ions ([Ca2+]i) in NaF effects on Rho/ROCK pathway and MLCK was investigated. We found that NaF elevated [Ca2+]i, whereas chelator BAPTA-AM attenuated increased RhoA and MLCK expression as well as ZO-1 rupture, thus, restoring barrier function. Collectively, abovementioned results suggest that NaF induces barrier impairment via Ca2+-dependent RhoA/ROCK pathway and MLCK, which in turn triggers MLC2 phosphorylation and rearrangement of ZO-1 and F-actin. These results provide potential therapeutic targets for fluoride-induced intestinal injury.

Assessment the role of some Bacillus strains in improvement rex rabbits resistance against ETEC challenge.

Increasing reports have indicated that specific strains of probiotic Bacillus have the potential to prevent diseases. The purpose of this study was to explore the effects of three Bacillus strains (Bacillus subtilis BSWJ2017001, Bacillus pumilus BSWJ2017002, and B. subtilis BSWJ2017003) mixture dietary supplementation on rex rabbits infected with enterotoxigenic Escherichia coli (ETEC). In this study, 60 35-day-old weaning rex rabbits were separated into two groups randomly: control group (fed basal diet with no antibiotics) and Bacillus strains group (fed basal diet containing 1.0 × 106 CFU/g Bacillus strains mixture). After 8 weeks of feeding, the rex rabbits were inoculated orally with 5.0 mL of ETEC (1.0 × 109 CFU/mL) and assessed at 0, 12, and 24 h. The Bacillus strains mixture attenuated the oxidative damage, diarrhea severity, and intestinal damage of ETEC infected rabbits. It also significantly increased the population of Lactobacillus spp., and Bifidobacterium spp., and decreased the population of Enterococcus spp.. Moreover, Bacillus strains group exhibited higher levels of toll-like receptor (TLR) 2, anti-inflammatory cytokines, secretory immunoglobulin A, and intestinal barrier-related genes than control group, as well as lower levels of TLR-4 and pro-inflammatory cytokines. These results demonstrated that Bacillus strains mixture could attenuate injury caused by ETEC and enhance disease resistance by improving specific intestinal microbiota members and immunity in weaning rex rabbits.

Ameliorating Effects of TRIM67 against Intestinal Inflammation and Barrier Dysfunction Induced by High Fat Diet in Obese Mice.

Tripartite Motif 67 (TRIM67) is an important member of TRIM family proteins, which participates in different cellular processes including immune response, proliferation, differentiation, carcinogenesis, and apoptosis. In recent years, a high fat diet (HFD) has remained one of the main causes of different metabolic diseases and increases in intestinal permeability as well as inducing intestinal inflammation. The current study investigated the protective effects of TRIM67 in the ileum and colon of obese mice. 4-week-old wild-type (WT) C57BL/6N mice and TRIM67 knockout (KO) C57BL/6N mice were selected and randomly divided into four sub-groups, which were fed with control diet (CTR) or HFD for 14 weeks. Samples were collected at the age of 18 weeks for analysis. To construct an in vitro obesity model, over-expressed IPEC-J2 cells (porcine intestinal cells) with Myc-TRIM67 were stimulated with palmitic acid (PA), and its effects on the expression level of TRM67, inflammatory cytokines, and barrier function were evaluated. The KO mice showed pathological lesions in the ileum and colon and this effect was more obvious in KO mice fed with HFD. In addition, KO mice fed with a HFD or CTR diet had increased intestinal inflammation, intestinal permeability, and oxidative stress compared to that WT mice fed with these diets, respectively. Moreover, IPEC-J2 cells were transfected with TRIM67 plasmid to perform the same experiments after stimulation with PA, and the results were found consistent with the in vivo evaluations. Taken together, our study proved for the first time that HFD and TRIM67 KO mice have synergistic damaging effects on the intestine, while TRIM67 plays an important protective role in HFD-induced intestinal damage.

Probiotic alleviate fluoride-induced memory impairment by reconstructing gut microbiota in mice.

Fluoride which is widespread in our environment and food due to its geological origin and industrial pollution has been identified as a developmental neurotoxicant. Gut-brain axis provides new insight into brain-derived injury. We previously found the psychoactive effects of a probiotic strain, Lactobacillus johnsonii BS15 against fluoride-induced memory dysfunction in mice by modulating the gut-brain axis. In this study, we aimed to detect the link between the reconstruction of gut microbiota and gut-brain axis through which probiotic alleviate fluoride-induced memory impairment. We also added an hour of water avoidance stress (WAS) before behavioral tests and sampling, aiming to demonstrate the preventive effects of the probiotic on fluoride-induced memory impairment after psychological stress. Mice were given fluoridated drinking water (sodium fluoride 100 ppm, corresponding to 37.8 ± 2.4 ppm F¯) for 70 days and administered with PBS or a probiotic strain, Lactobacillus johnsonii BS15 for 28 days prior to and throughout a 70 day exposure to sodium fluoride. Results showed that fluoride increases the hyperactivity of hypothalamic-pituitary-adrenal (HPA) axis and reduces the exploration ratio in novel object recognition (NOR) test and the spontaneous exploration during the T-maze test in mice following WAS, which were significantly improved by the probiotic. 16S rRNA sequencing showed a significant separation in ileal microbiota between the fluoride-treated mice and control mice. Lactobacillus was the main targeting bacteria and significantly reduced in fluoride-treated mice. BS15 reconstructed the fluoride-post microbiota and increased the relative abundance of Lactobacillus. D-lactate content and diamine oxidase (DAO) activity, two biomarkers of gut permeability were reduced in the serum of probiotic-inoculated mice. ZO-1, an intestinal tight junction protein was reduced by fluoride in mRNA, and its protein levels were increased by the probiotic treatment. Moreover, the hippocampus which is essential to learning and memory, down-regulated mRNA level of both the myelin-associated glycoprotein (MAG), and protein levels of brain-derived neurotrophic factor (BDNF), including the improvement of cAMP response element-binding protein (CREB) by BS15 in fluoride-exposed mice after WAS. Via spearman correlation analysis, Lactobacillus displayed significantly positive associations with the behavioral tests, levels of nerve development related factors, and intestinal tight junction proteins ZO-1, and negative association with TNF-α of the hippocampus, highlighting regulatory effects of gut bacteria on memory potential and gut barrier. These results suggested the psychoactive effects of BS15 on fluoride-induced memory dysfunction after psychological stress. In addition, there may be some correlations between fluoride-induced memory dysfunction and reconstruction of gut microbiota. AVAILABILITY OF DATA AND MATERIALS: 16S rRNA sequencing reads have uploaded to NCBI. The accession code of 16S rRNA sequencing reads in the National Center for Biotechnology Information (NCBI) BioProject database: PRJNA660154.

Efficacy of Bacillus methylotrophicus SY200 strain as feed additive against experimental Salmonella typhimurium infection in mice.

To investigate the effects of Bacillus methylotrophicus SY200 on Salmonella typhimurium (STM) infection in mice, a total of 36 three-week-old male mice were selected and randomly divided into 3 equal groups (N = 12). Group A and group B were fed with basal diet while group C was fed the basal diet supplemented with 0.1% (w/w) B. methylotrophicus SY200 during the 21 days experimental period. On the 14th day of the experiment, mice of group A were intragastrically administered with 0.5 ml of normal saline, group B and C were orally administered with 0.5 ml of STM suspension. On the first day and seventh day after STM challenge, the number of total white blood cells (WBCs) and neutrophils, relative weight of visceral organs, the number of Salmonella spp., Escherichia coli, Lactobacillus spp. and Bifidobacterium spp. in ileum and cecum, and diversity of cecal microflora were measured. The results showed that: on the first day and seventh day after STM challenge, the number of WBCs and neutrophils in the blood of the mice was the highest in group B, then followed by group C, and group A. On the first day after STM challenge, the relative weight of spleen in group C was significantly higher than that in group B (p < 0.05), moreover, compared with group B, B. methylotrophicus SY200 significantly reduced the number of Salmonella spp. and E. coli (p < 0.05), and increased the number of Lactobacillus spp. and Bifidobacterium spp. (p < 0.05) in the intestines of mice, and improved the Shannon-Wiener diversity (H), Simpson (E) and richness (S) indices of cecal flora of mice (p < 0.05). The results indicated that B. methylotrophicus SY200 could alleviate the inflammatory reaction after STM infection and resist the adverse effects of STM infection on mice intestinal flora.

Bacillus strains improve growth performance via enhancing digestive function and anti-disease ability in young and weaning rex rabbits.

Numerous studies have shown that probiotic Bacillus could promote growth and enhance anti-disease ability in animal. In present study, the mixture of three Bacillus strains, which were isolated from rex rabbits and showed high cellulose, protease, and amylase activities, was added into the diet for investigating its effects on young and weaning rex rabbits. For experiment 1, 40 young rex rabbits (9 weeks old) were randomly divided into four groups and fed with diets containing 0 (NC), 1.0 × 105 cfu/g (LC), 1.0 × 106 cfu/g (MC), and 1.0 × 107 cfu/g (HC) Bacillus strains for 4 weeks. For experiment 2, 80 weaning rex rabbits (5 weeks old) were randomly divided into four groups and fed with diet containing 0 (control), 1.0 × 105 cfu/g (T-1), 1.0 × 106 cfu/g (T-2), and 1.0 × 107 cfu/g (T-3) Bacillus strains for 8 weeks. The results showed that Bacillus strains at a dose of 1.0 × 106 cfu/g significantly enhanced growth performance, increased immune organ indexes, improved serum biochemical parameters, and heightened antioxidant capacity. It also markedly improved the intestinal microbiota by increasing Lactobacillus spp., Bacillus spp. counts, and decreased Escherichia coli count. In addition, the Bacillus mixture raised the concentrations of acetic acid, propionic acid, and butyric acid as well as protease, amylase, and cellulase activities of young and weaning rex rabbits. Moreover, for weaning rex rabbits, the inclusion of Bacillus strains also upregulated the abundance of cellulolytic bacteria and improved intestinal morphology. Therefore, our results indicated that Bacillus strains could facilitate the growth of young and weaning rex rabbits by improving digestive function and anti-disease ability. KEY POINTS: • Bacillus with high extracellular enzyme activity were isolated from rex rabbits. • Bacillus could improve growth performance of young and weaning rex rabbits. • The digestive function of young and weaning rex rabbits could be improved by Bacillus.

Transcriptome analysis revealed ameliorative effect of probiotic Lactobacillus johnsonii BS15 against subclinical necrotic enteritis induced hepatic inflammation in broilers.

Subclinical necrotic enteritis (SNE) broadly occurs in boilers, which reduces the growth performance by causing serious economic and social problems. The following study was conducted to better understand the molecular mechanism of the SNE on liver inflammation and to examine the innovative prevention of Lactobacillus johnsonii BS15 upon SNE. The research was based on the regulatory molecular mechanism of Lactobacillus johnsonii BS15, and its effect on liver inflammatory pathways in the broiler with SNE infection. Day old one hundred and eighty (Cobb 500) broiler chickens were distributed into 3 groups (control, SNE and BS15 group) and reared for 28 days. RNA sequencing was used for the analysis of gene expression extracted from liver samples. Gene expression was detected with the help of quantitative real-time PCR (qRT-PCR). RNA-Seq analysis revealed altered expressions of genes involved in liver inflammatory pathway. A total number of 385 genes were found as differentially expressed (DEGs) in the liver samples that belonged to SNE group as compared with the control liver samples (p < 0.05). Out of those 385 genes, 117 were down-regulated and 268 were up-regulated. The DEGs related to liver inflammation between control group and SNE group or SNE and BS15 groups, included cluster of differentiation 80 (CD80), Interleukin 1 beta (IL1B), Phosphoinositide 3- Kinase regulatory subunit 5 (PIK3R5), Toll-like receptor 4 (TLR4), Toll-like receptor 2 A (TLR2A), and proto-oncogene protein (FOS). The RNA-Seq analysis provided DEGs expression and this result was validated by qRT-PCR. Results confirmed that these genes are essential in the regulation of liver inflammation in the SNE infected chickens. Findings of current research indicated that the hepatic inflammation could be induced by SNE in broilers. Simultaneously, effects of SNE infection on liver could be subsided by improved TLRs signaling pathway with the naturally present prophylactic strategy as BS15.

Soy Isoflavones Ameliorate Fatty Acid Metabolism of Visceral Adipose Tissue by Increasing the AMPK Activity in Male Rats with Diet-Induced Obesity (DIO).

Soy isoflavones are natural active ingredients of soy plants that are beneficial to many metabolic diseases, especially obesity. Many studies have reported that obesity is closely related to visceral fatty acid metabolism, but the effect has not been well defined. In this study, we show that soy isoflavones improve visceral fatty acid metabolism in diet-induced obese male rats, which was indicated by reduced body weight and visceral fat cell area, as well as suppressed visceral fat synthesis and accelerated fat hydrolysis. We also found that common components of soy isoflavones, daidzein and genistein, were able to inhibit the lipid accumulation process in 3T3-L1 cells. Moreover, we showed that soy isoflavones can promote on AMP-activated protein kinase (AMPK) activity both in vivo and in vitro, which may be implicated in lipid metabolism regulation of soy isoflavones. Our study demonstrates the potential of soy isoflavones as a mechanism for regulating lipid homeostasis in visceral adipose tissue, proven to be beneficial for obesity treatment.

Surface Display of Antigen Protein VP8* of Porcine Rotavirus on Bacillus Subtilis Spores Using CotB as a Fusion Partner.

Porcine rotavirus is a major cause of acute viral gastroenteritis in suckling piglets, and vaccination is considered to be an effective measure to control these infections. The development of a live mucosal vaccine using Bacillus subtilis spores as an antigen delivery vehicle is a convenient and attractive vaccination strategy against porcine rotavirus. In this study, a shuttle vector was constructed for the spore surface display of the spike protein VP8* from porcine rotavirus (the genotype was G5P[7]). A successful display of the CotB-VP8* fusion protein on the spore surface was confirmed by Western blot and immunofluorescence microscopy analysis. The capacity for immune response generated after immunization with the recombinant strain was evaluated in a mouse model. The intestinal fecal IgA and serum IgG were detected by enzyme-linked-immunosorbent serologic assay (ELISA). Importantly, recombinant strain spores could elicit strong specific mucosal and humoral immune responses. These encouraging results suggest that recombinant B. subtilis BV could provide a strategy for a potential novel application approach to the development of a new and safe mucosal subunit vaccine against porcine rotavirus.

Analysis of hepatic transcriptome demonstrates altered lipid metabolism following Lactobacillus johnsonii BS15 prevention in chickens with subclinical necrotic enteritis.

BACKGROUND: Subclinical necrotic enteritis (SNE) widely outbreaks in chickens which inflicted growth-slowing, causing enormous social and economic burdens. To better understand the molecular underpinnings of SNE on lipid metabolism and explore novel preventative strategies against SNE, we studied the regulatory mechanism of a potential probiotic, Lactobacillus johnsonii BS15 on the lipid metabolism pathways involved in chickens with SNE. METHODS: One hundred eighty one-day-old chickens were randomly divided into three groups and arranged with basal diet (control and SNE group). Added with BS15 (1 × 106 cfu/g) or Man Rogosa Sharpe (MRS) liquid medium for 28 days. The hepatic gene expression of each group was then measured using high-throughput analysis methods (RNA-Seq). Quantitative real-time PCR (qRT-PCR) was used to detect the expression changes of the related genes. RESULTS: The results showed that there are eleven lipid metabolic pathways were found during the prevention of BS15 treatment in SNE chickens by RNA-Seq, including the peroxisome proliferator-activated receptor (PPAR) signaling pathway and arachidonic acid metabolism. BS15 notably facilitated the expressions of fatty acid binding protein 2 (FABP2), acyl-CoA synthetase bubblegum family member 1 (ACSBG1), perilipin 1 (PLIN1) and perilipin 2 (PLIN2), which were involved in PPAR signaling pathway of SNE chickens. Besides, suppression of phospholipase A2 group IVA (PLA2G4A) in arachidonic acid metabolism was observed in SNE chickens after BS15 prevention. The expression patterns of FABP2, ACSBG1, PLIN1, PLIN2 and PLA24G in qRT-PCR validation were consistent with RNA-Seq results. CONCLUSIONS: These findings indicate that SNE may affect the hepatic lipid metabolism of chickens. Meanwhile, BS15 pretreatment may provide a prospective natural prophylaxis strategy against SNE through improving the PPAR signaling pathway and arachidonic acid metabolism.

Controlling of growth performance, lipid deposits and fatty acid composition of chicken meat through a probiotic, Lactobacillus johnsonii during subclinical Clostridium perfringens infection.

BACKGROUND: Meat is considered as a major source of polyunsaturated fatty acid (PUFA) which is essential for humans, therefore its lipid level and fatty acid composition have drawn great attention. As no clinical sign can be found in chicks subclinically infected by Clostridium perfringens (CP), the meat may be purchased and eaten. The objective of the present study was to determine whether Lactobacillus johnsonii (LJ) can control the CP-caused impact on growth, lipid levels, fatty acid composition and other flavor or nutritional quality in the meat. METHODS: 480 one-day-old chicks were divided into four groups and fed with basal diet (control and CP group). Supplemented with 1 × 105 (L-LJ) and 1 × 106 (H-LJ) colony-forming unit (cfu), CP diet was fed for 42 days. From day 19 to 22, birds of CP and LJ groups were administered with CP twice per day and the control was administered with liver broth. RESULTS: LJ-treated chickens were free from negative influences on growth performance and significant decrease of abdominal fat deposit., LJ inhibited CP-caused shearing force and drip loss increase and pH 40 min and 24 h decrease after sacrifice. In addition, LJ exhibited a positive effect on muscle lipid peroxidation by significantly increasing SOD, CAT and GSH-Px activity and decreasing MDA level. Besides, LJ attenuated the decrease of intramuscular fat, total cholesterol and triglyceride contents caused by CP infection. However, levels of total protein and most of amino acids were not changed. CP infection decreased C18:3n-3 (α-LA), C20:4n-6, C20:5n-3(EPA), C22:4n-6, C22:5n-3, C22:6n-3(DHA), total PUFA, n-3 PUFA and PUFA:SFA ratio and increased C14:0, total SFA and n-6:n-3 ratio. LJ was found to protect the muscle from these changes. Meanwhile, the 28-day gut permeability level was higher in CP group. CONCLUSIONS: These findings suggest that CP may affect the growth performance of chicks and negatively influence lipid content and fatty acid composition in chicken meat. Meanwhile, LJ treatment may be effective in controlling these changes by reducing the increased gut permeability caused by CP subclinical infection.

Fermented Yupingfeng polysaccharides enhance immunity by improving the foregut microflora and intestinal barrier in weaning rex rabbits.

Yupingfeng (YPF) is a kind of Astragali radix-based ancient Chinese herbal supplemented with Atractylodis Macrocephalae Rhizoma and Radix Saposhnikoviae. Increasing evidence has proven the beneficial immunomodulating activity of YPF. However, the action mechanism(s) of it is not known. Here, we explored the immunomodulatory activity of unfermented Yupingfeng polysaccharides (UYP) and fermented Yupingfeng polysaccharides (FYP) obtained using Rhizopus oligosporus SH in weaning Rex rabbits. The results showed that both UYP and FYP exhibited notable growth-promoting and immune-enhancing activities, improvement of the intestinal flora homeostasis, and maintenance of intestinal barrier integrity and functionality. Notably, compared with UYP, FYP effectively enhanced average daily gain, organ indices, interleukin-2 (IL-2), IL-4, IL-10, tumor necrosis factor-alpha (TNF-α), TLR2, and TLR4 mRNA levels in spleen, IL-1, IL-2, IL-4, IL-6, IL-10, IL-12, TNF-α, and IFN-γ protein concentrations in serum, and TLR2 and TLR4 mRNA expressions in the gastrointestinal tract (GIT). Moreover, FYP exhibited greater beneficial effects in improving the intestinal flora, including augment flora diversity and the abundance of cellulolytic bacteria, reduction the abundance of Streptococcus spp. and Enterococcus spp. in the GIT, particularly the foregut and maintaining the intestinal barrier integrity and functionality by upregulating zonula occludens 1, claudin, polymeric immunoglobulin receptor, trefoil factor, and epidermal growth factor mRNA levels in the jejunum and ileum. Our results indicated the immunoenhancement effect of FYP is superior over that of UYP, which is probably related with the amelioration of the intestinal microflora and intestinal barrier in the foregut.

Effects of Bacillus licheniformis on the growth performance and expression of lipid metabolism-related genes in broiler chickens challenged with Clostridium perfringens-induced necrotic enteritis.

BACKGROUND: Necrotic enteritis (NE), caused by Clostridium perfringens, has cost the poultry industry $2 billion in losses. This study aimed to investigate the effect of Bacillus licheniformis as dietary supplement on the growth, serum antioxidant status, and expression of lipid-metabolism genes of broiler chickens with C. perfringens-induced NE. METHODS: A total of 240 one-day-old broilers were randomly grouped into four: a negative control, an NE experimental model (PC), chickens fed a diet supplemented with 30 % of fishmeal from day 14 onwards and challenged with coccidiosis vaccine (FC), and NE group supplied with feed containing 1.0 × 10(6) CFU/g B. licheniformis (BL). RESULTS: Body weight gain, feed conversion ratio, serum antioxidant status, and lipid-metabolism-gene expression were analyzed. In the PC group, FCR increased significantly whereas serum catalase and glutathione peroxidase activity decreased compared with NC group. Dietary B. licheniformis supplementation improved FCR and oxidative stress in experimental avian NE. Using Bacillus licheniformis as a direct-fed microbial (DFM) could also significantly upregulate catabolism-related genes, namely, peroxisome proliferator-activated receptor-α and carnitine palmitoyltransferase-1, in livers and changed the expression of lipid-anabolism genes. CONCLUSION: These results suggested that dietary B. licheniformis supplementation can enhance growth and antioxidant ability, as well as change the expression of genes related to fatty-acid synthesis and oxidation in the livers of NE-infected broilers.

Decreased microbial diversity and Lactobacillus group in the intestine of geriatric giant pandas (Ailuropoda melanoleuca).

It has been established beyond doubt that giant panda genome lacks lignin-degrading related enzyme, gastrointestinal microbes may play a vital role in digestion of highly fibrous bamboo diet. However, there is not much information available about the intestinal bacteria composition in captive giant pandas with different ages. In this study, we compared the intestinal bacterial community of 12 captive giant pandas from three different age groups (subadults, adults, and geriatrics) through PCR-denaturing gradient gel electrophoresis (DGGE) and real-time PCR analysis. Results indicated that microbial diversity in the intestine of adults was significantly higher than that of the geriatrics (p < 0.05), but not significant compared to the subadults (p > 0.05). The predominant bands in DGGE patterns shared by the twelve pandas were related to Firmicutes and Proteobacteria. Additionally, in comparison to healthy individuals, antibiotic-treated animals showed partial microbial dysbiosis. Real-time PCR analyses confirmed a significantly higher abundance of the Lactobacillus in the fecal microbiota of adults (p < 0.05), while other bacterial groups and species detected did not significantly differ among the three age groups (p > 0.05). This study revealed that captive giant pandas with different ages showed different intestinal bacteria composition.

Characterization of the cellulolytic bacteria communities along the gastrointestinal tract of Chinese Mongolian sheep by using PCR-DGGE and real-time PCR analysis.

A balanced gastrointestinal microbial ecosystem is crucial for the health and growth of animals. In the gastrointestinal tract (GIT) of ruminants, cellulolytic bacteria aid in the digestion and absorption of nutrients. Rumen contents and feces in ruminants are often used to assess gastrointestinal microbial communities; however, these sites do not guarantee to represent the diversity of microbes found in the entire GIT. In this study, we investigated the microbiota along the GIT of five Chinese Mongolian sheep using PCR-denaturing gradient gel electrophoresis (DGGE) and real-time PCR analysis. Results indicated that microbiota were more abundant in the stomach and large intestine than in the small intestine. DGGE and real-time PCR revealed the predominance of Firmicutes and Bacteroidetes in the GIT. Meanwhile, Ruminococcus flavefaciens and Clostridium cluster IV showed significant difference in their abundance along the GIT (P < 0.05). Fibrobacter succinogenes was the most dominant species, followed by Ruminococcus albus and R. flavefaciens. The ileum harbored a larger number of cellulolytic bacteria, particularly-Clostridium cluster IV, than reported previously. In addition, comparisons between microbiota in the rumen and rectum indicated similar number of total bacteria, Firmicutes, Bacteroidetes, F. succinogenes, Butyrivibrio fibrisolvens, Clostridium cluster IV, and Clostridium cluster XIVa, whereas the number of R. albus and R. flavefaciens was higher in the rumen. This study investigated the composition and quantification of GIT microbial community in Chinese Mongolian sheep, and revealed for the first time the cellulolytic bacterial community in these sheep.

Preventing non-alcoholic fatty liver disease through Lactobacillus johnsonii BS15 by attenuating inflammation and mitochondrial injury and improving gut environment in obese mice.

The increasing prevalence of obesity worldwide is associated with a parallel increase in non-alcoholic fatty liver disease (NAFLD). To investigate the effect of Lactobacillus johnsonii BS15 on NAFLD, 120 male ICR mice were randomly divided into four groups and administrated with BS15 (2 × 10(7) cfu/0.2 mL or 2 × 10(8) cfu/0.2 mL) or phosphate buffered saline (PBS) throughout a 17-week experimental period. The mice were fed with normal chow diet (NCD) 5 weeks before the experimental period. Afterward, with the exception of the PBS group, NCD was changed into high-fat diet (HFD) for the remaining experimental period. Results showed that BS15-treated HFD mice were protected from hepatic steatosis and hepatocyte apoptosis. BS15 exhibited a positive effect on liver lipid peroxidation through an anti-oxidative stress activity by enhancing the liver antioxidant defense system. In addition, BS15 inhibited the insulin resistance; decreased the mRNA levels of acetyl-CoA carboxylase 1, fatty acid synthase, and peroxisome proliferator-activated receptor γ; and increased the expression of the fasting-induced adipose factor in livers. Meanwhile, BS15 attenuated mitochondria abnormalities when the content of uncoupling protein-2 decreased and cytochrome c increased in NAFLD mice. BS15 also reduced the level of serum lipopolysaccharide in NAFLD mice by lowering the intestinal permeability and adjusting gut flora, followed by the downregulation of the TNFα mRNA level in liver and the serum level of C-reactive protein. These findings suggest that BS15 may be effective in preventing NAFLD induced by HFD.

Toxicological effects of dietary nickel chloride on intestinal microbiota.

This study was designed to evaluate the toxicological effect of dietary nickel chloride (NiCl2) on the counts of intestinal bacteria and diversity of microorganisms in broilers. Plate counting and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) assays were used. A total of 240 one-day-old avian broilers chicks were divided into four equal groups and kept on corn-soybean basal diet along with supplementation of 0, 300, 600 and 900 mg/kg NiCl2 for 42 days. Samples were taken at 21 and 42 days of age during the experiment. The bacterial count results showed that dietary NiCl2 in the range of 300 to 900 mg/kg decreased the counts of Bifidobacterium spp. and Lactobacillus, increased Escherichia coli (E. coli) and Enterococcus spp. in the ileum and cecum. PCR-DGGE analysis showed that bacterial band numbers, profile similarity, and the Shannon index of the ileum and cecum were all decreased in the 300, 600, and 900 mg/kg groups at 21 and 42 days of age. In conclusion, dietary NiCl2 affected the amount and diversity of intestinal microbiota in the ileum and cecum of broilers. This finding implies that NiCl2 has toxicological effect on the intestinal ecosystem and, possibly functions.