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Gastroenterology Dec 2023Pien Tze Huang (PZH) is a well-established traditional medicine with beneficial effects against inflammation and cancer. We aimed to explore the chemopreventive effect...
BACKGROUND & AIMS
Pien Tze Huang (PZH) is a well-established traditional medicine with beneficial effects against inflammation and cancer. We aimed to explore the chemopreventive effect of PZH in colorectal cancer (CRC) through modulating gut microbiota.
METHODS
CRC mouse models were established by azoxymethane plus dextran sulfate sodium treatment or in Apc mice treated with or without PZH (270 mg/kg and 540 mg/kg). Gut barrier function was determined by means of intestinal permeability assays and transmission electron microscopy. Fecal microbiota and metabolites were analyzed by means of metagenomic sequencing and liquid chromatography mass spectrometry, respectively. Germ-free mice or antibiotic-treated mice were used as models of microbiota depletion.
RESULTS
PZH inhibited colorectal tumorigenesis in azoxymethane plus dextran sulfate sodium-treated mice and in Apc mice in a dose-dependent manner. PZH treatment altered the gut microbiota profile, with an increased abundance of probiotics Pseudobutyrivibrio xylanivorans and Eubacterium limosum, while pathogenic bacteria Aeromonas veronii, Campylobacter jejuni, Collinsella aerofaciens, and Peptoniphilus harei were depleted. In addition, PZH increased beneficial metabolites taurine and hypotaurine, bile acids, and unsaturated fatty acids, and significantly restored gut barrier function. Transcriptomic profiling revealed that PZH inhibited PI3K-Akt, interleukin-17, tumor necrosis factor, and cytokine-chemokine signaling. Notably, the chemopreventive effect of PZH involved both microbiota-dependent and -independent mechanisms. Fecal microbiota transplantation from PZH-treated mice to germ-free mice partly recapitulated the chemopreventive effects of PZH. PZH components ginsenoside-F2 and ginsenoside-Re demonstrated inhibitory effects on CRC cells and primary organoids, and PZH also inhibited tumorigenesis in azoxymethane plus dextran sulfate sodium-treated germ-free mice.
CONCLUSIONS
PZH manipulated gut microbiota and metabolites toward a more favorable profile, improved gut barrier function, and suppressed oncogenic and pro-inflammatory pathways, thereby suppressing colorectal carcinogenesis.
Topics: Mice; Animals; Signal Transduction; Gastrointestinal Microbiome; Dextran Sulfate; Phosphatidylinositol 3-Kinases; Apoptosis; Medicine, Traditional; Colorectal Neoplasms; Carcinogenesis; Azoxymethane
PubMed: 37704113
DOI: 10.1053/j.gastro.2023.08.052 -
Journal of Agricultural and Food... Nov 2023Lactic acid bacteria (LAB) were screened from (red sea bass), and their antimicrobial activities were evaluated against two species isolated from the , namely, (AV)...
Lactic acid bacteria (LAB) were screened from (red sea bass), and their antimicrobial activities were evaluated against two species isolated from the , namely, (AV) and (AJ). Three LAB isolates, MU8 (EF_8), MU2 (EFL_2), and MU9 (EFL_9), were found to inhibit both AV and AJ; however, their cell-free supernatant (CFS) did not do so. Interestingly, bacteriocin-like substances (BLS) induced by cocultures of EF_8 with AV exhibited the highest antimicrobial activity against both sp. The size of BLS was less than 1.0 kDa; the purified BLS were susceptible to proteinase K digestion, indicating that they are peptides. BLS contained 13 identified peptides derived from as determined by liquid chromatography-tandem mass spectrometry. Cocultures of Gram-positive-producing and -inducing LAB strains have been used to increase bacteriocin yields. To our knowledge, this is the first report describing inducible BLS produced by cocultures of Gram-positive-producing and Gram-negative-inducing strains.
Topics: Enterococcus faecium; Bacteriocins; Aeromonas veronii; Coculture Techniques; Aeromonas; Peptides; Anti-Infective Agents; Anti-Bacterial Agents
PubMed: 37779478
DOI: 10.1021/acs.jafc.3c04019 -
Veterinary Microbiology Aug 2023Aeromonas veronii is a Gram-negative opportunistic bacterium found in fish, poultry and humans and has occasionally been associated with disease although not generally...
Aeromonas veronii is a Gram-negative opportunistic bacterium found in fish, poultry and humans and has occasionally been associated with disease although not generally considered a poultry pathogen. A. veronii was recently isolated from both healthy and condemned broiler carcasses at a major Danish abattoir. In this study, we did a whole genomic analysis of 24A. veronii strains from the abattoir to determine their potential sources and relatedness as well as their pathogenic potential, antimicrobial resistance determinants and associated mobile elements. No strains were multi-drug resistant, but all strains carried the beta-lactam resistance genes cphA3 and bla without being phenotypically resistant to carbapenems. One strain carried an IncA plasmid with tet(A), tet(B) and tet(E) genes. A phylogenetic tree including public A. veronii sequences showed that our isolates were not clonal but were dispersed around the phylogenetic tree, suggesting a diffuse spread of A. veronii across human, aquatic and poultry samples. Strains carried different virulence factors known to be associated with pathogenesis and severity of disease in animals and humans, e.g. type II (aerolysin, amylases, proteases, and cytotoxic enterotoxin Act) and III secretion systems where the latter has been associated with mortality in hospitalized patients. Although our genomic analysis of A. veronii shows zoonotic potential, epidemiological studies of human gastro-enteritis cases of A. veronii associated with consumption of broiler meat are needed. It remains to be proven if A. veronii is a true poultry pathogen and part of the established microflora in abattoirs and the gut-intestinal microflora of poultry.
Topics: Humans; Animals; Aeromonas veronii; Aeromonas; Chickens; Virulence; Phylogeny; Genomics; Denmark; Gram-Negative Bacterial Infections
PubMed: 37207528
DOI: 10.1016/j.vetmic.2023.109772 -
BMC Genomics Feb 2024DNA N6-methyladenosine (6mA), as an important epigenetic modification, widely exists in bacterial genomes and participates in the regulation of toxicity, antibiotic...
BACKGROUND
DNA N6-methyladenosine (6mA), as an important epigenetic modification, widely exists in bacterial genomes and participates in the regulation of toxicity, antibiotic resistance, and antioxidant. With the continuous development of sequencing technology, more 6mA sites have been identified in bacterial genomes, but few studies have focused on the distribution characteristics of 6mA at the whole-genome level and its association with gene expression and function.
RESULTS
This study conducted an in-depth analysis of the 6mA in the genomes of two pathogenic bacteria, Aeromonas veronii and Helicobacter pylori. The results showed that the 6mA was widely distributed in both strains. In A. veronii, 6mA sites were enriched at 3' end of protein-coding genes, exhibiting a certain inhibitory effect on gene expression. Genes with low 6mA density were associated with cell motility. While in H. pylori, 6mA sites were enriched at 5' end of protein-coding genes, potentially enhancing gene expression. Genes with low 6mA density were closely related to defense mechanism.
CONCLUSIONS
This study elucidated the distribution characteristics of 6mA in A. veronii and H. pylori, highlighting the effects of 6mA on gene expression and function. These findings provide valuable insights into the epigenetic regulation and functional characteristics of A. veronii and H. pylori.
Topics: Helicobacter pylori; Epigenesis, Genetic; Aeromonas veronii; DNA; Adenosine; DNA Methylation
PubMed: 38331763
DOI: 10.1186/s12864-024-10074-y -
Animals : An Open Access Journal From... Aug 2023The objective of this study was to understand biological characteristics of one bacteria strain named as VPG which was isolated from multiple organs of a dead captive...
The objective of this study was to understand biological characteristics of one bacteria strain named as VPG which was isolated from multiple organs of a dead captive giant panda cub. Here, we use biochemical tests, 16S rRNA and genes for bacterial identification, the disk diffusion method for antibiotic resistance phenotype, smart chip real-time PCR for the antibiotic resistance genotype, multiplex PCR for determination of virulence genes, and the acute toxicity test in mice for testing the pathogenicity of isolates. The isolate was identified as strain based on the biochemical properties and genetic analysis. We found that the strain carried 31 antibiotic resistance genes, revealed antimicrobial resistance phenotypically to several antibiotics including penicillin, ampicillin, oxacillin, amoxicillin, imipenem, and vancomycin, and carried virulence genes including , , , , , , and . The main pathological changes in giant panda were congestion, necrotic lesions and a large number of bacteria in multiple organs. In addition, the LD in Kunming mice infected with strain VGP was 5.14 × 10 CFU/mL by intraperitoneal injection. Infection with strain VGP led to considerable histological lesions such as hemorrhage of internal organs, necrosis of lymphocytes and neurons in Kunming mice. Taken together, these results suggest that infection with strain VGP would be an important causes of death in this giant panda cub.
PubMed: 37685043
DOI: 10.3390/ani13172779 -
Pathogens (Basel, Switzerland) Nov 2023We studied the phenotypic and genomic characteristics related to the virulence and antibiotic resistance of two strains, which were co-isolated before an outbreak of...
We studied the phenotypic and genomic characteristics related to the virulence and antibiotic resistance of two strains, which were co-isolated before an outbreak of among diseased seabass on Agathonisi Island, Greece, in April 2015. The first strain, AG2.13.2, is a potentially pathogenic mesophilic variant of , and the second, AG2.13.5, corresponds to an related to KN-Mc-11N1 with an ANI value of 97.32%. AG2.13.2 lacks the type III secretion system just like other mesophilic strains of . This characteristic has been associated with lower virulence. However, the genome of AG2.13.2 contains other important virulence factors such as type II and type VI secretion systems, and toxins such as , aerolysin /, and different types of hemolysins. The strain also carries several genes associated with antibiotic resistance such as the efflux pump, and exhibits resistance to tetracycline, ampicillin, and oxolinic acid. In an in vivo challenge test with gilthead seabream larvae, the bv strain AG5.28.6 exhibited the highest virulence among all tested strains. Conversely, both and showed minimal virulence when administered alone. Interestingly, when bv AG5.28.6 was co-administered with , the larvae survival probability increased compared to those exposed to bv AG5.28.6 alone. This finding indicates an antagonistic interaction between bv AG5.28.6 and AG2.13.5. The co-administration of bv AG5.28.6 with did not yield distinct survival probabilities. Our results validate that the primary pathogen responsible for European seabass aeromoniasis is bv .
PubMed: 38003801
DOI: 10.3390/pathogens12111337 -
Microorganisms Mar 2024is widespread in aquatic environments and is responsible for infecting various aquatic animals. In this study, a dominant strain was isolated from the hepatopancreas of...
is widespread in aquatic environments and is responsible for infecting various aquatic animals. In this study, a dominant strain was isolated from the hepatopancreas of diseased and was named JDM1-1. According to its morphological, physiological, and biochemical characteristics and molecular identification, isolate JDM1-1 was identified as . The results of artificial challenge showed isolate JDM1-1 had high pathogenicity to with an LD value of 8.35 × 10 CFU/mL during the challenge test. Histopathological analysis revealed severe damage in the hepatopancreas and gills of the diseased prawns, characterized by the enlargement of the hepatic tubule lumen and gaps between the tubules as well as clubbing and degeneration observed at the distal end of the gill filament. Eight virulence-related genes, namely , , , , , , , and , were screened by PCR assay. In addition, virulence factor detection showed that the JDM1-1 isolate produced lipase, lecithinase, gelatinase, and hemolysin. Furthermore, the mRNA expression profiles of immune-related genes of following infection, including , , , and were assessed, and the results revealed a significant upregulation in the hepatopancreas and intestines at different hours post infection. This study demonstrates that is a causative agent associated with massive die-offs of and contributes valuable insights into the pathogenesis and host defense mechanisms of invasion.
PubMed: 38674638
DOI: 10.3390/microorganisms12040694 -
Antibiotics (Basel, Switzerland) Jun 2023is a Gram-negative bacterial species that causes disease in fish and is nowadays increasingly recurrent in enteric infections of humans. This study was performed to...
is a Gram-negative bacterial species that causes disease in fish and is nowadays increasingly recurrent in enteric infections of humans. This study was performed to characterize newly sequenced isolates by comparing them with complete genomes deposited at the NCBI (National Center for Biotechnology Information). Nine isolates from fish, environments, and humans from the São Francisco Valley (Petrolina, Pernambuco, Brazil) were sequenced and compared with complete genomes available in public databases to gain insight into taxonomic assignment and to better understand virulence and resistance profiles of this species within the One Health context. One local genome and four NCBI genomes were misidentified as . A total of 239 virulence genes were identified in the local genomes, with most encoding adhesion, motility, and secretion systems. In total, 60 genes involved with resistance to 22 classes of antibiotics were identified in the genomes, including and . The results suggest that the use of methods such as ANI is essential to avoid misclassification of the genomes. The virulence content of from local isolates is similar to those complete genomes deposited at the NCBI. Genes encoding colistin resistance are widespread in the species, requiring greater attention for surveillance systems.
PubMed: 37370358
DOI: 10.3390/antibiotics12061039 -
Antibiotics (Basel, Switzerland) Feb 2024spp. are environmental bacteria able to infect animals and humans. Here, we aim to evaluate the role of biofilms in persistence in freshwater. were isolated from...
spp. are environmental bacteria able to infect animals and humans. Here, we aim to evaluate the role of biofilms in persistence in freshwater. were isolated from water and biofilm samples and identified by Vitek-MS and sequencing. Antibiotic susceptibility profiles were determined according to EUCAST, and a crystal violet assay was used to assess biofilm assembly. MTT and the enumeration of colony-forming units were used to evaluate biofilm and planktonic susceptibility to chlorination, respectively. Identification at the species level was challenging, suggesting the need to improve the used methodologies. Five different species (, , , and ) were identified from water, and one species was identified from biofilms (). and presented resistance to different antibiotics, whith the highest resistance rate observed for (multiple antibiotic resistance index of 0.25). Of the 21 isolates, 11 were biofilm producers, and 10 of them were strong biofilm producers (SBPs). The SBPs presented increased tolerance to chlorine disinfection when compared with their planktonic counterparts. In order to elucidate the mechanisms underlying biofilm tolerance to chlorine and support the importance of preventing biofilm assembly in water reservoirs, further research is required.
PubMed: 38391552
DOI: 10.3390/antibiotics13020166 -
Journal of Medical Case Reports Mar 2024Aeromonas veronii is a very rare and highly pathogenic microorganism. We investigate the clinical characteristics and significance of endogenous endophthalmitis caused...
BACKGROUND
Aeromonas veronii is a very rare and highly pathogenic microorganism. We investigate the clinical characteristics and significance of endogenous endophthalmitis caused by Aeromonas veronii in our patient.
CASE PRESENTATION
A 30-year-old Asian women with systemic lupus erythematosus, uremia, and hypertension developed acute infectious endophthalmitis caused by Aeromonas veronii. After emergency vitrectomy and antibiotic therapy, the clinical condition worsened requiring enucleation.
CONCLUSIONS
Aeromonas veronii can cause infection in the human eye, which can manifest as acute endophthalmitis. Early diagnosis and targeted therapy are important for successful treatment.
Topics: Humans; Female; Adult; Aeromonas veronii; Endophthalmitis; Anti-Bacterial Agents; Vitrectomy; Aeromonas; Gram-Negative Bacterial Infections
PubMed: 38504363
DOI: 10.1186/s13256-024-04412-7