Search Results (1,888)

We investigated the effect of probiotic Bacillus velezensis strains (LSSA01, 15AP4 and 2084) on pathogens causing post-weaning diarrhea in piglets (Enterotoxigenic Escherichia coli, Clostridium perfringens, Salmonella spp.). We studied the effect of B. velezensis and its cell-free supernatant on (1) pathogen growth; (2) IPEC-J2 cell cytokine and tight junction protein expression; (3) IPEC-J2 cell ‘wound’ recovery; (4) adhesion to IPEC-J2 cells and pathogen exclusion; and (5) Caenorhabditis elegans survival following pathogen exposure. Cell-free supernatant (CFS) from all strains inhibited the growth of ETEC F4 and F18 (by 36.9–53.2%; p < 0.05). One or more strains inhibited C. perfringens and Salmonella spp. (p < 0.05). Strain 2084 CFS increased IL-8 expression (+12.0% vs. control; p < 0.05; 6 h incubation), whereas LSSA01 CFS increased the expression of tight junction proteins (p < 0.05 vs. control; 6 h incubation) and accelerated 96 h ‘wound’ healing. Colony-forming units (CFUs) of all strains displayed a higher binding affinity to IPEC-J2 cells than 12 ETEC isolates, reduced adhesion of ETEC F4 and F18 and extended C. elegans survival over 30 d. The results indicate that probiotic B. velezensis strains have potential for use in the control of PWD pathogens. Full article

In poultry production, antibiotics have been excessively used as growth promoters to support well-being and decrease mortality caused by pathogenic microorganisms. The overuse of antibiotics has led to the emergence of antibiotic-resistant bacteria and the presence of antibiotic residues in poultry products. To counteract this problem, probiotics could be used as adjuncts or as substitutes for preserving a diverse and balanced microflora to prevent the colonization and multiplication of pathogenic bacteria in the GI tract. This study aimed to isolate and characterize the potential probiotic properties of lactic acid bacteria from the small intestine of 23-week-old broiler breeders, with the goal of identifying potential probiotic candidates. Four phenotypically healthy broiler breeders were selected, and intestinal contents were aseptically collected and cultured on MRS agar. From the initial pool of 39 colonies, six isolates were identified based on Gram-positive and catalase-negative characteristics and further classified using 16S rRNA sequencing as Levilactobacillus brevis (n = 3), Pediococcus pentosaceus (n = 2), and Streptococcus salivarius (n = 1). These strains were further evaluated for probiotic properties such as transit resistance to simulated upper gastrointestinal conditions, antagonist activity, haemolytic activity, and cell surface properties such as autoaggregation, co-aggregation and hydrophobicity, in vitro. L. brevis NKFS8 showed good tolerance to pH 3, while P. pentosaceus NKSF10 exhibited good tolerance to pH 4 acidic conditions. All isolates demonstrated good survivability in bile salt concentration of 3% (w/v), with P. pentosaceus NKSF10 exhibiting the highest tolerance. The isolates showed a wide range of antagonistic activity against the test pathogens Pseudomonas aeruginosa (ATCC 27853), Salmonella typhimurium, Salmonella enterica (ATCC 13314), Staphylococcus aureus (ATCC 29213), and Listeria monocytogenes (ATCC 7644). Furthermore, these strains exhibited good auto-aggregation, co-aggregation, and hydrophobicity properties. In conclusion, lactic acid bacteria from the small intestine of broiler breeders present a valuable prospect for the development of effective probiotics. These probiotics can be utilized as a supplementary inclusion in poultry feed, obviating the need for antibiotics as growth promoters. Nevertheless, additional in vivo studies are required to closely monitor and assess the effects of probiotics on the gastrointestinal system of chickens. Full article

In response to the global antimicrobial resistance and residue issues, most countries and regions have implemented comprehensive bans on the use of growth-promoting antibiotics in animal feed formulations. Catechins are a group of polyphenolic compounds that are naturally present in many fruits and plant-derived foods, emerging as potential antibiotic-alternative additives for promoting gut health and production performance in poultry farming. The compounds demonstrate dual biological functions: mitigating oxidative tissue damage and actively remodeling gut microbiota composition by suppressing enteric pathogens (e.g., Clostridium) and enriching beneficial bacteria (e.g., Bifidobacterium). Such multifaceted regulation enhances intestinal barrier integrity, thereby improving nutrient absorption and translating into measurable production benefits, including elevated growth rates and feed conversion efficiency. The current research suggests that the added levels of catechins in chicken diets ranges from 40 to 600 mg/kg. However, the research and application of catechins in chicken production are still at the initial stage, which requires more attention worldwide and further mechanism exploration. This mini-review synthesizes recent research findings on the effects of catechins on chicken health, aiming to promote the formulation of feed additive strategies using plant-derived compounds such as catechins as substitutes for antibiotics, to maintain the health of poultry and other animals while preserving production performance. Full article

Citrobacter braakii can colonize the intestinal tract of humans and animals and occasionally act as opportunistic pathogen. Although isolated from food and the environment, its potential as a foodborne pathogen remains uncertain. Twenty C. braakii isolates were previously collected from salami and soft cheese artisanal productions. In the present study, the potentialities of C. braakii as a food safety hazard were explored by a genomic comparison of C. braakii newly sequenced genomes with publicly available genomes, including those of clinical relevance, and a pathogenicity assessment in Galleria mellonella as an in vivo infection model. Phylogenomic reconstruction revealed that one salami clone and two C. braakii genomes of the soft cheese production were closely related (from 11 to 28 core SNP differences) to C. braakii publicly available clinical genomes. All genomes carried the chromosomally located bla_CMY and/or qnrB genes and were resistant to cephalosporins and/or had reduced susceptibility to ciprofloxacin. G. mellonella larvae showed 90% mortality after challenge with C. braakii strains carrying the vex and tvi operons coding for the capsular polysaccharide (Vi antigen), in comparison to 40% of strains lacking these two operons. The high mortality rate of vex- and tvi-positive C. braakii isolated from food processing plants suggests C. braakii to be a possible foodborne hazard. Full article

Flagellates of the genus Giardia are intestinal parasites with a broad host range. Several Giardia duodenalis variants (assemblages) recently elevated to species rank—G. duodenalis (assemblage A1), G. intestinalis (A2) and Giardia enterica (B) are human pathogens. Giardia enterica has been reported in some hystricomorph rodents such as wild crested porcupines (Hystrix cristata), but no data were previously available from Brazilian porcupines (Coendou prehensilis) and naked mole rats (Heterocephalus glaber). The aim of this study is to genetically identify the Giardia isolates from these three rodent species, all housed in a zoological institution. Fecal samples were processed using the Bailenger concentration method, and DNA was extracted from the sediments using commercial kits. Partial PCR amplification and sequencing of the glutamate dehydrogenase, beta-giardin, and triose-phosphate isomerase genes revealed that all isolates belonged to G. enterica, showing 99–100% identity with sequences available in GenBank. Prevalences could not be reliably estimated due to small group sizes and the resulting proportions may be biased. To our knowledge, this is the first report identifying Giardia (G. enterica) in C. prehensilis and H. glaber, thus expanding the known host range of this parasite species and reinforcing the importance of surveillance in captive wild hosts. Full article

Diabetic nephropathy (DN) represents a severe microvascular complication of diabetes mellitus with limited therapeutic options, many of which are accompanied by considerable adverse effects. Opuntia ficus-indica (OFI) fruit, rich in vitamins, dietary fiber, and fatty acids, contains numerous bioactive compounds, including phytosterols, polysaccharides, and flavonoids that demonstrate significant potential in diabetes management. The flavonoid fraction derived from OFI fruit (OFI-F) has exhibited pronounced anti-inflammatory, antioxidant, and gut microbiota modulatory properties. However, the efficacy of OFI-F in ameliorating DN and its underlying mechanisms remain inadequately elucidated. This investigation examined the therapeutic potential of OFI-F in DN and explored its mechanistic pathways. Our findings demonstrate that OFI-F administration significantly attenuated renal injury and intestinal barrier dysfunction in the DN murine model. OFI-F intervention resulted in multiple beneficial outcomes in DN mice, including the mitigation of weight loss, reduction in hyperglycemia, decrease in renal coefficient index, and the attenuation of renal injury. An analysis of gut microbiota composition revealed that OFI-F administration favorably modulated the intestinal microbial community by enhancing the abundance of beneficial bacteria while concomitantly reducing populations of potentially pathogenic bacteria. Additionally, OFI-F treatment promoted the production of short-chain fatty acids (SCFAs), which contributed substantially to renoprotection and inflammatory resolution. Antibiotic intervention studies further confirmed the indispensable role of gut microbiota in mediating the renoprotective effects of OFI-F. In conclusion, this study provides compelling evidence supporting the therapeutic potential of OFI-F in DN management through the concurrent modulation of gut microbiota and renal function, offering a promising nutraceutical approach for alleviating renal injury in DN. Full article

Group A rotaviruses (RVAs) are a major cause of acute dehydrating diarrhea in infants and young animals worldwide. In rabbits, RVAs are associated with enteric disease, likely in combination with other pathogens. We report the identification and characterization of a lapine RVA strain in an Italian rabbit breeding farm. Increased mortality rates associated with enteric symptoms were reported in the facility in post-weaning rabbits around 40 days of age. By quantitative RT-PCR, an RVA strain was identified in the intestinal contents of deceased rabbits. A PCR-based enrichment protocol coupled with Nanopore sequencing allowed the reconstruction of the nearly complete genome of a rabbit RVA strain, Rabbit-wt/ITA/36-9/2022/G3P[14], with a genotype constellation (G3-P[14]-I2-R2-C2-M3-A9-N2-T6-E5-H3) conserved among lapine RVAs. Each of the 11 gene segments displayed high nucleotide identity and phylogenetic clustering with lapine rotavirus strains, as well as two Belgian human G3P[14] strains, which had been shown to have a zoonotic (lapine) origin. However, the NSP2 gene of strain 36-9 clustered closer with a group of rare human G3P[9] strains, suggesting a common path during their evolution. Gathering sequence data on animal RVAs is pivotal to reconstructing the history of homologous and heterologous RVAs in various mammals, including humans. Full article

Background/Objectives: Colorectal neoplasms rank as the third most prevalent cancer globally and stand as the second leading cause of cancer-related mortality. Its etiology is multifaceted, pointing to the role of microorganisms within the human microbiota in its development. Notably, the high prevalence of oral pathogens like Fusobacterium nucleatum and Parvimonas micra is implicated in inducing gut dysbiosis and stimulating the proliferation and metastasis of cancer cells. Therefore, this study aimed to evaluate in vitro the biological effects of extracts from Juglans regia and Pfaffia paniculata. Methods: Phytochemical analysis was carried out by HPLC, and the antioxidant effect was determined by DPPH. Antimicrobial activity was investigated on F. nucleatum and P. micra planktonic and biofilms. Metabolic activity and genotoxicity were performed. Results:J. regia and P. paniculata expressed CE50 37.26 and 1367.57 mcg, respectively. The extracts exhibited a minimum bactericidal concentration of 1.73 and 0.48 mg/mL for J. regia and P. paniculata, respectively. Reduction superiorly 90% of P. micra biofilms. Metabolic activity was varied proportionally to the extract concentration, and no genotoxic effects were observed. Conclusions: The J. regia extract has great antioxidant activity and could be used as an alternative in combating pathogens associated with the onset of dysbiosis and tumor progression in colorectal neoplasms. Nevertheless, further studies are needed to validate their clinical applicability. Full article

Background: Birnaviruses infect a wide range of aquatic and terrestrial hosts, including several economically important fish species. This study aimed to isolate and characterize a novel birnavirus strain from mandarin fish (Siniperca chuatsi), a high-value freshwater species in Chinese aquaculture. Methods: A novel strain, designated mandarin fish birnavirus (MFBV), was isolated from diseased fish and propagated in SCK cells. The complete genome was determined using high-throughput sequencing and RACE. Viral replication kinetics, tissue distribution, and pathogenicity were assessed through in vitro infection, RT-qPCR, histopathology, and experimental challenges. In addition, disinfectant sensitivity and environmental stability were evaluated. Results: The MFBV genome comprises two segments (A: 3539 bp; B: 2719 bp), and phylogenetic analysis revealed close relatedness to largemouth bass birnavirus (LBBV) and Lates calcarifer birnavirus (LCBV). MFBV displayed rapid replication in SCK cells, completing a replication cycle in 8–10 h. In juvenile and fry fish, an experimental infection caused acute disease with cumulative mortality ranging from 41.8% to 83.6%, with fry showing higher susceptibility. Viral RNA was detected in multiple tissues (7.9 × 10⁶–7.9 × 10⁷ copies/μg RNA), and histopathological lesions were observed in the intestine, spleen, and kidney. MFBV was highly sensitive to glutaraldehyde (20 ppm), while other disinfectants showed reduced efficacy. Viral half-life ranged from 36.5 to 144.5 h at room temperature. Conclusions: These findings demonstrate that MFBV can induce acute systemic infection in mandarin fish. The results offer new insights into the genomic and biological features of birnaviruses, contributing to improved disease management and viral taxonomy. Full article

In hepatology, there is growing interest in identifying the mechanisms and risk factors underlying liver diseases with increasing incidence, with particular focus on metabolic dysfunction-associated steatotic liver disease (MASLD) and its complications. Simple sugars have been recognized as key contributors to liver injury and disease progression, not only in the context of MASLD but also beyond. As a result, numerous studies have aimed to elucidate their role in liver pathophysiology. Specifically, simple sugars have been associated with pivotal mechanisms involved in the onset of liver diseases, including inflammation, de novo lipogenesis, oxidative stress, insulin resistance, and dysbiosis with increased intestinal permeability. These mechanisms collectively contribute to a significant association between simple sugar intake and liver diseases of varying stages and severity. The scientific evidence available to date has not only clarified potential pathogenic mechanisms and clinical correlations but also led to the identification of potential therapeutic targets, encompassing both lifestyle interventions and molecular approaches. This review aims to provide a comprehensive analysis of the associations between simple sugar intake, liver injury, and liver diseases. To this end, we conducted an extensive review of the literature, selecting the most relevant and up-to-date studies on the topic. Full article

Inflammatory bowel disease (IBD)-associated colorectal cancer (CRC) remains a significant clinical challenge due to its link with chronic inflammation and the inherent limitations of current prevention and surveillance strategies. The cGAS-STING pathway has emerged as a key player in the immune regulation of inflammation-driven carcinogenesis, demonstrating both protective and pathogenic roles. This review examines the contrasting roles of the cGAS-STING signaling pathway in intestinal inflammation and colitis-associated cancer (CAC), emphasizing its promise as a target for cancer prevention strategies. Evidence suggests that modulating this pathway could preserve epithelial integrity, limit chronic inflammation, and bolster anti-tumor immunity. Despite advancements in therapies like mesalazine and surveillance colonoscopy programs, gaps in efficacy remain, particularly for Crohn’s disease and high-risk populations. Future research should focus on integrating cGAS-STING-targeted approaches with existing modalities to provide personalized and less invasive strategies for CAC prevention. By harnessing this pathway’s therapeutic potential, a paradigm shift in managing IBD-associated CRC may be achieved, addressing the challenges of long-term disease surveillance and prevention. Full article

Galacto-oligosaccharides (GOS) are recognized prebiotics with extensive applications in animal nutrition. This study aimed to elucidate the effects of chlortetracycline (CTC) supplementation alongside GOS on growth performance, intestinal morphology, and microbiota composition in weaned piglets. A total of 72 weaned piglets [(Duroc × (Landrace × Yorkshire)] with an initial body weight of 7.64 ± 0.15 kg were randomly assigned to three dietary treatments: a corn–soybean meal-based diet (CON), a corn–soybean meal-based diet supplemented with chlortetracycline (CTC) at 75 mg/kg, and a diet with 1500 mg/kg GOS. The experiment spanned 14 days, divided into early (1–7 days) and late (7–14 days) stages. The results indicated that the GOS group exhibited a significant increase in body weight (BW) by day 14 and improved average daily gain (ADG) from day 1 to 14, alongside a decreased feed-to-gain ratio and diarrhea incidence (p < 0.05). Notably, GOS supplementation enhanced the villus height of the jejunum and increased the ratio of villus height to crypt depth compared to the CON group, although no significant differences were observed between GOS and AntB groups. Additionally, the number of goblet cells in the colonic crypts increased significantly with GOS supplementation. High-throughput 16S rRNA gene sequencing revealed an increased relative abundance of Firmicutes in the GOS group, coupled with a decrease in Bacteroidetes and Spirochaetota. Beneficial bacteria such as Lactobacillus and Faecalibacterium were significantly enriched, while potentially pathogenic bacteria, including Clostridium_sensu_stricto_1 and Treponema, were reduced. In summary, dietary GOS supplementation can enhance beneficial microbiota while diminishing harmful species, thereby improving intestinal morphology and growth performance in weaned piglets. Consequently, GOS emerges as a promising alternative to in-feed antibiotics in contemporary animal husbandry. Full article

In ex situ conservation, gut bacteria and fungi play a crucial role in maintaining the intestinal microecological balance of the gut, and disruptions in this system may negatively impact host health. The South China tiger (Panthera tigris amoyensis) is a critically endangered tiger subspecies currently surviving under human-managed care and captive breeding programs, with only a small number of individuals remaining. Disruption in the gut microbiota, particularly the proliferation of pathogenic bacteria, can be fatal for cubs. This study analyzed the composition and seasonal changes of the gut bacterial and fungal communities of South China tigers in captive and semi-released environments during the winter of 2023 and the summer of 2024, using 16S rRNA and ITS high-throughput sequencing. The results showed that the dominant gut bacteria were Bacillota, Actinomycetota, Fusobacteriota, Pseudomonadota, and Bacteroidota. The abundance of Bacillota decreased in summer and was slightly lower in captive tigers than in semi-released tigers. Fungal communities were dominated by Ascomycota, with a negative correlation observed between Ascomycota and Basidiomycota. The abundance of Ascomycetes was lower in summer but significantly higher in semi-released tigers than in captive ones. Diversity analysis revealed no significant effects of the season or the environment on bacterial α-diversity, and fungal α-diversity was also not significantly affected by seasonal variation. However, microbial diversity increased under semi-free-range conditions, with fungal richness significantly higher than in captive environments (p < 0.01). Principal coordinate analysis (PCoA) based on Bray–Curtis distances revealed significant differences in the community structures of both bacterial (Adonis, R² = 0.2364, p = 0.001) and fungal (Adonis, R² = 0.1542, p = 0.001) communities across different seasons and environments. These findings provide valuable insights into the health management strategies and ecological adaptation of South China tigers. Full article

The intestinal health and functionality of animals play pivotal roles in nutrient digestion and absorption, as well as in maintaining defense against pathogenic invasions. These biological processes are modulated by various determinants, including husbandry conditions, dietary composition, and gut microbial ecology. The excessive use of anthropogenic antibiotics may disrupt intestinal microbiota composition, potentially leading to dysbiosis that directly compromises host homeostasis. While Lactobacillus species are recognized for their immunomodulatory properties, their precise mechanisms in regulating host anti-inflammatory gene expression and influencing mucosal layer maturation, particularly regarding E. coli colonization resistance, require further elucidation. To investigate the regulatory mechanisms of Lactobacillus in relation to intestinal architecture and function during E. coli infection, we established a colonic infection model using Bal b/c mice, conducting systematic analyses of intestinal morphology, inflammatory mediator profiles, and microbial community dynamics. Our results demonstrate that Lactobacillus supplementation (Pediococcus acidilactici) effectively mitigated E. coli O78-induced enteritis, with co-administration during infection facilitating the restoration of physiological parameters, including body mass, intestinal histoarchitecture, and microbial metabolic functions. Microbiome profiling revealed that the Lactobacillus intervention significantly elevated Lactococcus abundance while reducing Weissella populations (p < 0.05), concurrently enhancing metabolic pathways related to nutrient assimilation and environmental signal processing (including translation mechanisms, ribosomal biogenesis, amino acid transport metabolism, and energy transduction systems; p < 0.05). Mechanistically, Lactobacillus administration attenuated E. coli-induced intestinal pathology through multiple pathways: downregulating pro-inflammatory cytokine expression (IL-1β, IL-1α, and TNF-α), upregulating epithelial junctional complexes (Occludin, Claudin-1, and ZO-1), and stimulating mucin biosynthesis (MUC1 and MUC2; p < 0.05). These modifications collectively enhanced mucosal barrier integrity and promoted epithelial maturation. This investigation advances our comprehension of microbiota–host crosstalk during enteropathogenic infections under probiotic intervention, offering valuable insights for developing novel nutritional strategies and microbial management protocols in animal husbandry. Full article

ACLF is a severe stage of liver cirrhosis, characterized by multiple organ failure, systemic inflammation, and high short-term mortality. The intestinal microbiota (IM) influences its pathophysiology; however, there are currently no studies in Latin American populations. Therefore, we analyzed IM and its relationships with sepsis, organ failure, and mortality. In parallel, we quantified serum lipopolysaccharides as a marker of bacterial translocation. Fecal samples from 33 patients and 20 healthy controls (HCs) were obtained. The IMs were characterized by 16S-rRNA amplicon sequencing, the metagenomic functional predictive profiles were analyzed by PICRUSt2, and LPS quantification was performed by ELISA. Patients with ACLF showed significant alterations in alpha and beta diversity compared to the HCs. A strong dominance index accurately predicted 28-day and 90-day mortalities. The IMs showed a polarization toward Proteobacteria associated with increased LPS. The LPS correlated with clinical severity, organ dysfunction, and higher pathogenic taxa. The Klebsiella/Faecalibacterium ratio showed good performance in identifying sepsis (AUROC = 0.83). Furthermore, Morganella, Proteus, and Klebsiella were enriched in patients with multiorgan failure. Lactobacillus, Escherichia/Shigella, Veillonella, and Ruminococcus gnavus exhibited potential in predicting 28- and 90-day mortalities. The IM alterations in ACLF may be useful as clinical biomarkers of poor prognosis, primarily for mortality and sepsis. These findings are representative of western Mexico. Full article