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Communications Biology May 2024Fusobacterium nucleatum, a gram-negative oral bacterium, has been consistently validated as a strong contributor to the progression of several types of cancer, including...
Fusobacterium nucleatum, a gram-negative oral bacterium, has been consistently validated as a strong contributor to the progression of several types of cancer, including colorectal (CRC) and pancreatic cancer. While previous in vitro studies have shown that intracellular F. nucleatum enhances malignant phenotypes such as cell migration, the dependence of this regulation on features of the tumor microenvironment (TME) such as oxygen levels are wholly uncharacterized. Here we examine the influence of hypoxia in facilitating F. nucleatum invasion and its effects on host responses focusing on changes in the global epigenome and transcriptome. Using a multiomic approach, we analyze epigenomic alterations of H3K27ac and global transcriptomic alterations sustained within a hypoxia and normoxia conditioned CRC cell line HCT116 at 24 h following initial infection with F. nucleatum. Our findings reveal that intracellular F. nucleatum activates signaling pathways and biological processes in host cells similar to those induced upon hypoxia conditioning in the absence of infection. Furthermore, we show that a hypoxic TME favors F. nucleatum invasion and persistence and therefore infection under hypoxia may amplify malignant transformation by exacerbating the effects induced by hypoxia alone. These results motivate future studies to investigate host-microbe interactions in tumor tissue relevant conditions that more accurately define parameters for targeted cancer therapies.
Topics: Humans; Fusobacterium nucleatum; Colorectal Neoplasms; Epigenome; Transcriptome; HCT116 Cells; Fusobacterium Infections; Oxygen; Tumor Microenvironment; Gene Expression Regulation, Neoplastic
PubMed: 38720110
DOI: 10.1038/s42003-024-06201-w -
Signal Transduction and Targeted Therapy May 2024
Topics: Colorectal Neoplasms; Humans; Fusobacterium
PubMed: 38719840
DOI: 10.1038/s41392-024-01844-x -
Journal of Endodontics May 2024In this study, we used metatranscriptomics for the first time to investigate microbial composition, functional signatures, and antimicrobial resistance gene expression...
INTRODUCTION
In this study, we used metatranscriptomics for the first time to investigate microbial composition, functional signatures, and antimicrobial resistance gene expression in endodontic infections.
METHODS
Root canal samples were collected from ten teeth, including five primary and five persistent/secondary endodontic infections. RNA from endodontic samples was extracted, and RNA sequencing was performed on a NovaSeq6000 system (Illumina). Taxonomic analysis was performed using the Kraken2 bacterial database. Then, sequences with a taxonomic classification were annotated against the Universal Protein Knowledgebase for functional annotation and the Comprehensive Antibiotic Resistance Database for AR-like gene identification.
RESULTS
Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria represented the dominant phyla, whereas Fusobacteria, Spirochetes, and Synergistetes were among the nondominant phyla. The top ten species were mainly represented by obligate (or quasiobligate) anaerobes, including Gram-negative (eg, Capnocytophaga sp. oral taxon 323, Fusobacterium nucleatum, Prevotella intermedia, Prevotella oris, Tannerella forsythia, and Tannerella sp. oral taxon HOT-286) and Gram-positive species (eg, Olsenella uli and Parvimonas micra). Transcripts encoding moonlighting proteins (eg, glycolytic proteins, translational elongation factors, chaperonin, and heat shock proteins) were highly expressed, potentially affecting bacterial adhesion, biofilm formation, host defense evasion, and inflammation induction. Endodontic bacteria expressed genes conferring resistance to antibiotic classes commonly used in dentistry, with a high prevalence and expression of tetracycline and lincosamide resistance genes. Antibiotic efflux and antibiotic target alteration/protection were the main resistance mechanisms.
CONCLUSIONS
Metatranscriptomics revealed the activity of potential endodontic pathogens, which expressed putative virulence factors and a wide diversity of genes potentially involved in AR.
PubMed: 38719087
DOI: 10.1016/j.joen.2024.03.015 -
Effect of luminescent materials on the aquatic macrophyte Vallisneria natans and periphytic biofilm.Plant Physiology and Biochemistry : PPB Jun 2024Luminescent materials can adjust the spectrum of light energy utilization by plants. However, current research on the effects of luminescent materials on aquatic plants...
Luminescent materials can adjust the spectrum of light energy utilization by plants. However, current research on the effects of luminescent materials on aquatic plants and periphytic biofilms is limited. This study investigated the effects of the luminescent materials 4-(di-p-tolylamino) benzaldehyde-A (DTB-A) and 4-(di-p-tolylamino) benzaldehyde-M (DTB-M) on the submerged macrophyte Vallisneria natans (V. natans) and periphytic biofilm. Result demonstrated that low concentrations of DTB (0.1 μM) significantly promoted the growth and photosynthetic rate of V. natans. In terms of enzyme activity, exposure to a higher concentration of DTB (10 μM) increased the activities of peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT). A combination of DTB-A and DTB-M treatment significantly changed the V. natans morphology and physiological characteristics, reducing the thickness of the cell wall and subsequently, promoting protein accumulation in leaves. There was no difference in the removal of ammonia or phosphate by V. natans at the 0.1 μM concentration, and the removal of ammonia and phosphate by V. natans decreased significantly as the concentration of luminescent material increased. A total of 3563 OTUs were identified in the biofilm community. The microbial community was dominated by Pseudomonas and Fusobacteria. Furthermore, results showed that an obvious decrease in diversity in the DTB-A and DTB-M mixed treatment group. In addition, the migratory aggregation of DTB molecules in plants was observed by fluorescence imaging. Overall, these findings extend our understanding of the mechanism of effect of luminescent materials on submerged macrophytes and their periphytic microorganisms.
Topics: Biofilms; Hydrocharitaceae; Benzaldehydes; Photosynthesis; Luminescence; Catalase; Peroxidase; Plant Leaves; Superoxide Dismutase; Luminescent Agents
PubMed: 38718531
DOI: 10.1016/j.plaphy.2024.108672 -
Organic Letters May 2024, a colorectal-cancer-associated oncomicrobe, can trigger or accelerate numerous pathologies. We report the first synthesis of a conjugation-ready disaccharide...
, a colorectal-cancer-associated oncomicrobe, can trigger or accelerate numerous pathologies. We report the first synthesis of a conjugation-ready disaccharide containing six amino groups from ATCC 23726 O-antigen. Rare 2,3-diamido-d-glucuronic acid amide and 2-acetamido-4-amino-d-fucose were synthesized from d-glucosamine through configuration inversion, nucleophilic substitution, C6 oxidation, and C6 deoxygenation. A judicious choice of protecting groups and reaction conditions enabled the selective installation of -acetyl, -propanoyl, -formyl, and carboxamido groups.
Topics: Fusobacterium nucleatum; O Antigens; Molecular Structure; Disaccharides
PubMed: 38717147
DOI: 10.1021/acs.orglett.4c01344 -
Journal of Photochemistry and... Jul 2024Periodontitis, a chronic infectious disease leading to gingival atrophy and potential tooth loss through alveolar bone resorption, is closely linked to the oral...
Periodontitis, a chronic infectious disease leading to gingival atrophy and potential tooth loss through alveolar bone resorption, is closely linked to the oral microbiome. Fusobacterium nucleatum, known to facilitate late-stage bacterial colonization in the oral microbiome, plays a crucial role in the onset of periodontitis. Controlling F. nucleatum abundance is vital for preventing and treating periodontal disease. Photodynamic therapy combined with 5-aminolevulinic acid (ALA-PDT) has been reported to be bactericidal against Pseudomonas aeruginosa and Staphylococcus aureus. We aimed to investigate the bactericidal potential of ALA-PDT against F. nucleatum, which was evaluated by examining the impact of varying 5-ALA concentrations, culture time, and light intensity. After ALA-PDT treatment, DNA was extracted from interdental plaque samples collected from 10 volunteers and sequenced using the Illumina MiSeq platform. To further elucidate the bactericidal mechanism of ALA-PDT, porphyrins were extracted from F. nucleatum following cultivation with 5-ALA and subsequently analyzed using fluorescence spectra. ALA-PDT showed a significant bactericidal effect against F. nucleatum. Its bactericidal activity demonstrated a positive correlation with culture time and light intensity. Microbiota analysis revealed no significant alteration in α-diversity within the ALA-PDT group, although there was a noteworthy reduction in the proportion of the genus Fusobacterium. Furthermore, fluorescence spectral analysis indicated that F. nucleatum produced an excitable photosensitive substance following the addition of 5-ALA. Overall, if further studies confirm these results, this combined therapy could be an effective strategy for reducing the prevalence of periodontitis.
Topics: Fusobacterium nucleatum; Aminolevulinic Acid; Humans; Photochemotherapy; Periodontitis; Photosensitizing Agents; Adult; Male; Anti-Bacterial Agents; Female; Microbiota
PubMed: 38714001
DOI: 10.1016/j.jphotobiol.2024.112926 -
Poultry Science Jul 2024This study aimed to evaluate the effect of low molecular weight Acanthopanax polysaccharides on simulated digestion, probiotics, and intestinal flora of broilers in...
Prebiotic characteristics of degraded polysaccharides from Acanthopanax senticosus polysaccharide on broilers gut microbiota based on in vitro digestion and fecal fermentation.
This study aimed to evaluate the effect of low molecular weight Acanthopanax polysaccharides on simulated digestion, probiotics, and intestinal flora of broilers in vitro. The experiments were carried out by HO-Vc degradation of Acanthopanax polysaccharides, in vitro simulated digestion to evaluate the digestive performance of polysaccharides with different molecular weights, in vitro probiotic evaluation of the probiotic effect of polysaccharides on lactobacilli and bifidobacteria, in vitro anaerobic fermentation and high-throughput sequencing of 16S rRNA genes to study the impact of Acanthopanax polysaccharides on the intestinal flora of broilers, and the effect of Acanthopanax polysaccharides on the short-chain fatty acids of intestines were determined by GC-MS method. The results showed that the molecular weight of Acanthopanax polysaccharide (ASPS) was 9,543 Da, and the molecular weights of polysaccharides ASPS-1 and ASPS-2 were reduced to 4,288 Da and 3,822 Da after degradation, and the particle sizes, PDIs, and viscosities were also significantly decreased. ASPS-1 has anti-digestive properties and better in vitro probiotic properties. The addition of ASPS-1 regulates the structure of intestinal microorganisms by regulating fecalibacterium to produce short-chain fatty acids, promoting the colonization of beneficial bacteria such as fecalibacterium, paraprevotella and diminishing the prevalence of detrimental bacteria such as Fusobacteria. Interestingly the ASPS-1 group found higher levels of Paraprevotella, which degraded trypsin in the gut, reducing inflammation, acted as a gut protector, and was influential in increasing the levels of acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, and total SCFAs in the fermented feces. Therefore, the degraded ASPS-1 can better regulate the structure of intestinal flora and promote the production of SCFAs, creating possibilities for its use as a potential prebiotic, which is conducive to the intestinal health of poultry.
Topics: Animals; Gastrointestinal Microbiome; Chickens; Eleutherococcus; Polysaccharides; Prebiotics; Feces; Digestion; Fermentation; Animal Feed; Diet; Fatty Acids, Volatile
PubMed: 38713991
DOI: 10.1016/j.psj.2024.103807 -
Gut Microbes 2024Mucinous colorectal cancer (CRC) is a common histological subtype of colorectal adenocarcinoma, associated with a poor response to chemoradiotherapy. The commensal...
Mucinous colorectal cancer (CRC) is a common histological subtype of colorectal adenocarcinoma, associated with a poor response to chemoradiotherapy. The commensal facultative anaerobes fusobacteria, have been associated with poor prognosis specifically in mesenchymal CRC. Interestingly, fusobacterial infection is especially prevalent in mucinous CRC. The objective of this study was therefore to increase our understanding of beneficial and detrimental effects of fusobacterial infection, by contrasting host cell signaling and immune responses in areas of high vs. low infection, using mucinous rectal cancer as a clinically relevant example. We employed spatial transcriptomic profiling of 106 regions of interest from 8 mucinous rectal cancer samples to study gene expression in the epithelial and immune segments across regions of high versus low fusobacterial infection. Fusobacteria high regions were associated with increased oxidative stress, DNA damage, and P53 signaling. Meanwhile regions of low fusobacterial prevalence were characterized by elevated JAK-STAT, Il-17, Il-1, chemokine and TNF signaling. Immune masks within fusobacterial high regions were characterized by elevated proportions of cytotoxic (CD8+) T cells ( = 0.037), natural killer (NK) cells ( < 0.001), B-cells ( < 0.001), and gamma delta T cells ( = 0.003). Meanwhile, fusobacteria low regions were associated with significantly greater M2 macrophage ( < 0.001), fibroblast ( < 0.001), pericyte ( = 0.002), and endothelial ( < 0.001) counts.
Topics: Humans; Rectal Neoplasms; Signal Transduction; DNA Damage; Gene Expression Profiling; Male; Female; Middle Aged; Transcriptome; Aged
PubMed: 38709233
DOI: 10.1080/19490976.2024.2350149 -
BMC Oral Health May 2024To evaluate the antibacterial effectiveness of a combination of ε-poly-L-lysine (ε-PL), funme peptide (FP) as well as domiphen against oral pathogens, and assess the... (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVE
To evaluate the antibacterial effectiveness of a combination of ε-poly-L-lysine (ε-PL), funme peptide (FP) as well as domiphen against oral pathogens, and assess the efficacy of a BOP® mouthwash supplemented with this combination in reducing halitosis and supragingival plaque in a clinical trial.
MATERIALS AND METHODS
The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the compound against Fusobacterium nucleatum, Porphyromonas gingivalis, Streptococcus mutans, and Aggregatibacter actinomycetemcomitans were determined by the gradient dilution method. Subsequently, the CCK-8 assay was used to detect the toxicity of mouthwash on human gingival fibroblastst, and the effectiveness in reducing halitosis and supragingival plaque of the mouthwash supplemented with the combination was analyzed by a randomized, double-blind, parallel-controlled clinical trial.
RESULTS
The combination exhibited significant inhibitory effects on tested oral pathogens with the MIC < 1.56% (v/v) and the MBC < 3.13% (v/v), and the mouthwash containing this combination did not inhibit the viability of human gingival fibroblasts at the test concentrations. The clinical trial showed that the test group displayed notably lower volatile sulfur compounds (VSCs) at 0, 10, 24 h, and 7 d post-mouthwash (P < 0.05), compared with the baseline. After 7 days, the VSC levels of the and control groups were reduced by 50.27% and 32.12%, respectively, and notably cutting severe halitosis by 57.03% in the test group. Additionally, the Plaque Index (PLI) of the test and control group decreased by 54.55% and 8.38%, respectively, and there was a significant difference in PLI between the two groups after 7 days (P < 0.01).
CONCLUSIONS
The combination of ε-PL, FP and domiphen demonstrated potent inhibitory and bactericidal effects against the tested oral pathogens, and the newly formulated mouthwash added with the combination exhibited anti-dental plaque and anti-halitosis properties in a clinical trial and was safe.
TRIAL REGISTRATION
The randomized controlled clinical trial was registered on Chinese Clinical Trial Registry (No. ChiCTR2300073816, Date: 21/07/2023).
Topics: Humans; Halitosis; Mouthwashes; Dental Plaque; Double-Blind Method; Male; Female; Polylysine; Adult; Microbial Sensitivity Tests; Young Adult; Anti-Bacterial Agents; Porphyromonas gingivalis; Fusobacterium nucleatum; Fibroblasts; Peptides; Aggregatibacter actinomycetemcomitans; Streptococcus mutans
PubMed: 38702623
DOI: 10.1186/s12903-024-04255-0 -
Archives of Microbiology May 2024Aggregatibacter actinomycetemcomitans is an opportunistic Gram-negative periodontopathogen strongly associated with periodontitis and infective endocarditis. Recent... (Comparative Study)
Comparative Study
Aggregatibacter actinomycetemcomitans is an opportunistic Gram-negative periodontopathogen strongly associated with periodontitis and infective endocarditis. Recent evidence suggests that periodontopathogens can influence the initiation and progression of oral squamous cell carcinoma (OSCC). Herein we aimed to investigate the effect of A. actinomycetemcomitans-derived extracellular vesicles (EVs) on OSCC cell behavior compared with EVs from periodontopathogens known to associate with carcinogenesis. EVs were isolated from: A. actinomycetemcomitans and its mutant strains lacking the cytolethal distending toxin (CDT) or lipopolysaccharide (LPS) O-antigen; Porphyromonas gingivalis; Fusobacterium nucleatum; and Parvimonas micra. The effect of EVs on primary and metastatic OSCC cells was assessed using cell proliferation, apoptosis, migration, invasion, and tubulogenesis assays. A. actinomycetemcomitans-derived EVs reduced the metastatic cancer cell proliferation, invasion, tubulogenesis, and increased apoptosis, mostly in CDT- and LPS O-antigen-dependent manner. EVs from F. nucleatum impaired the metastatic cancer cell proliferation and induced the apoptosis rates in all OSCC cell lines. EVs enhanced cancer cell migration regardless of bacterial species. In sum, this is the first study demonstrating the influence of A. actinomycetemcomitans-derived EVs on oral cancer in comparison with other periodontopathogens. Our findings revealed a potential antitumorigenic effect of these EVs on metastatic OSCC cells, which warrants further in vivo investigations.
Topics: Aggregatibacter actinomycetemcomitans; Extracellular Vesicles; Mouth Neoplasms; Humans; Cell Line, Tumor; Apoptosis; Cell Proliferation; Cell Movement; Fusobacterium nucleatum; Carcinoma, Squamous Cell; Porphyromonas gingivalis
PubMed: 38702412
DOI: 10.1007/s00203-024-03976-8