-
Nutrients May 2024The imbalance of gut microbiota is an important factor leading to inflammatory bowel disease (IBD). Diffusible signal factor (DSF) is a novel quorum-sensing signal that...
The imbalance of gut microbiota is an important factor leading to inflammatory bowel disease (IBD). Diffusible signal factor (DSF) is a novel quorum-sensing signal that regulates bacterial growth, metabolism, pathogenicity, and host immune response. This study aimed to explore the therapeutic effect and underlying mechanisms of DSF in a zebrafish colitis model induced by sodium dextran sulfate (DSS). The results showed that intake of DSF can significantly improve intestinal symptoms in the zebrafish colitis model, including ameliorating the shortening of the intestine, reducing the increase in the goblet cell number, and restoring intestinal pathological damage. DSF inhibited the upregulation of inflammation-related genes and promoted the expression of claudin1 and occludin1 to protect the tightness of intestinal tissue. The gut microbiome analysis demonstrated that DSF treatment helped the gut microbiota of the zebrafish colitis model recover to normal at the phylum and genus levels, especially in terms of pathogenic bacteria; DSF treatment downregulated the relative abundance of and , and it was confirmed in microbiological experiments that DSF could effectively inhibit the colonization and infection of these two pathogens in the intestine. This study suggests that DSF can alleviate colitis by inhibiting the proliferation of intestinal pathogens and inflammatory responses in the intestine. Therefore, DSF has the potential to become a dietary supplement that assists in the antibiotic and nutritional treatment of IBD.
Topics: Animals; Zebrafish; Dextran Sulfate; Gastrointestinal Microbiome; Colitis; Disease Models, Animal; Quorum Sensing; Intestines; Aeromonas hydrophila; Inflammation; Staphylococcus aureus
PubMed: 38892496
DOI: 10.3390/nu16111562 -
BMC Research Notes Jun 2024The aim of this study was to quantify and identify metabolites of Ice Nucleation Active (INA) bacteria as an anti-biofilm agent against biofilms of fish pathogens such...
OBJECTIVES
The aim of this study was to quantify and identify metabolites of Ice Nucleation Active (INA) bacteria as an anti-biofilm agent against biofilms of fish pathogens such as Aeromonas hydrophila and Streptococcus agalactiae.
RESULTS
Ice nucleation active bacteria, which have the ability to catalyze ice nucleation, isolated from rainwater in previous studies, were used. All INA isolates were tested in several assays, including the antimicrobial test, which uses streptomycin as the positive control and none of the isolates were found positive in the antimicrobial test. As for the quorum quenching assay, it was found that four out of ten isolates were able to disturb the communication system in Chromobacterium violaceum wild type, which was used as the indicator bacteria. On the next assay, all ten isolates were tested for Biofilm Inhibition and Destruction and showed anti-biofilm activity with the highest percentage inhibition of 33.49% by isolate A40 against A. hydrophila and 77.26% by isolate A19 against S. agalactiae. C1 performed the highest destruction against A. hydrophila and S. agalactiae, with percentages of 32.11% and 51.88%, respectively. As for the GC-MS analysis, supernatants of INA bacteria contain bioactive compounds such as sarcosine and fatty acids, which are known to have antibiofilm activity against several biofilm-forming bacteria. Through 16s rRNA sequencing, identified bacteria are from the Pantoea, Enterobacter, and Acinetobacter genera. As for the conclusion, ice nucleation active bacteria metabolites tested showed positive results against pathogenic bacteria Aeromonas hydrophila and Streptococcus agalactiae in destructing and inhibiting biofilm growth.
Topics: Biofilms; Aeromonas hydrophila; Streptococcus agalactiae; Anti-Bacterial Agents; Aquaculture; Fish Diseases; Animals; RNA, Ribosomal, 16S; Microbial Sensitivity Tests; Gram-Negative Bacterial Infections; Ice; Streptococcal Infections; Quorum Sensing
PubMed: 38886828
DOI: 10.1186/s13104-024-06821-9 -
Ecotoxicology and Environmental Safety Jul 2024This study aimed to evaluate the effect of adding liquid extract of algae (Hypnea musciformis, Grateloupia acuminata, and Sargassum muticum) (HGS) and Magnesium oxide...
Synergistic effect of green synthesis magnesium oxide nanoparticles and seaweed extract on improving water quality, health benefits, and disease resistance in Nile tilapia.
This study aimed to evaluate the effect of adding liquid extract of algae (Hypnea musciformis, Grateloupia acuminata, and Sargassum muticum) (HGS) and Magnesium oxide nanoparticles (MgO NPs) using this extract to rear water of Oreochromis niloticus, on improving culture water indices, growth performance, digestive enzyme, hemato-biochemical characters, immune, antioxidative responses, and resistance after challenged by Aeromonas hydrophila with specific refer to the potential role of the mixture in vitro as resistance against three strains bacteria (Aeromonas sobria, Pseudomonas fluorescens, P. aeruginosa) and one parasite (Cichlidogyrus tilapia). The first group represented control, HGS0, whereas the other group, HGS5, HGS10, and HGS15 mL of liquid extract, as well as all groups with 7.5 μg mL MgO-NPs added to culture water of O. niloticus, for 60 days. Data showed that increasing levels at HGS 10 and HGS15 mL in to-culture water significantly enhanced growth-stimulating digestive enzyme activity and a significantly improved survival rate of O. niloticus after being challenged with A. hydrophila than in the control group. The total viability, coliform, fecal coliform count, and heavy metal in muscle partially decreased at HGS 10 and HGS15 mL than in the control group. Correspondingly, the highest positive effect on hemato-biochemical indices was noticed at levels HGS 10 and HGS15 mL. Fish noticed an improvement in immune and antioxidant indices compared to control groups partially at HGS 10 and HGS15 mL. Interestingly, fish cultured in rearing water with the mixture provided downregulated the related inflammatory genes (HSP70, TNF, IL-1β, and IL-8) partially at HGS15 mL. In vitro, the mixture showed positive efficiency as an antibacterial and partially antiparasitic at HGS 10 and HGS15 mL. This study proposes utilizing a mixture of (HGS) and (MgO-NPs) with optimum levels of 10-15 mL in cultured water to improve water indices, growth, health status, and increased resistance of O. niloticus against bacterial and parasitic infection.
Topics: Animals; Magnesium Oxide; Cichlids; Disease Resistance; Water Quality; Seaweed; Fish Diseases; Plant Extracts; Nanoparticles; Green Chemistry Technology; Metal Nanoparticles; Aeromonas hydrophila; Sargassum
PubMed: 38843743
DOI: 10.1016/j.ecoenv.2024.116522 -
BMC Veterinary Research Jun 2024The liver-expressed antimicrobial peptide 2 (LEAP2) plays a pivotal role in the host's immune response against pathogenic microorganisms. Numerous such antimicrobial...
BACKGROUND
The liver-expressed antimicrobial peptide 2 (LEAP2) plays a pivotal role in the host's immune response against pathogenic microorganisms. Numerous such antimicrobial peptides have recently been shown to mitigate infection risk in fish, and studying those harboured by the economically important fish Acrossocheilus fasciatus is imperative for enhancing its immune responses against pathogenic microorganisms. In this study, we cloned and sequenced LEAP2 cDNA from A. fasciatus to examine its expression in immune tissues and investigate the structure-activity relationships of its intramolecular disulphide bonds.
RESULTS
The predicted amino acid sequence of A. fasciatus LEAP2 was found to include a signal peptide, pro-domain, and mature peptide. Sequence analysis indicated that A. fasciatus LEAP2 is a member of the fish LEAP2A cluster and is closely related to Cyprinus carpio LEAP2A. A. fasciatus LEAP2 transcripts were expressed in various tissues, with the head kidney exhibiting the highest mRNA levels. Upon exposure to Aeromonas hydrophila infection, LEAP2 expression was significantly upregulated in the liver, head kidney, and spleen. A mature peptide of A. fasciatus LEAP2, consisting of two disulphide bonds (Af-LEAP2-cys), and a linear form of the LEAP2 mature peptide (Af-LEAP2) were chemically synthesised. The circular dichroism spectroscopy result shows differences between the secondary structures of Af-LEAP2 and Af-LEAP2-cys, with a lower proportion of alpha helix and a higher proportion of random coil in Af-LEAP2. Af-LEAP2 exhibited potent antimicrobial activity against most tested bacteria, including Acinetobacter guillouiae, Pseudomonas aeruginosa, Staphylococcus saprophyticus, and Staphylococcus warneri. In contrast, Af-LEAP2-cys demonstrated weak or no antibacterial activity against the tested bacteria. Af-LEAP2 had a disruptive effect on bacterial cell membrane integrity, whereas Af-LEAP2-cys did not exhibit this effect. Additionally, neither Af-LEAP2 nor Af-LEAP2-cys displayed any observable ability to hydrolyse the genomic DNA of P. aeruginosa.
CONCLUSIONS
Our study provides clear evidence that linear LEAP2 exhibits better antibacterial activity than oxidised LEAP2, thereby confirming, for the first time, this phenomenon in fish.
Topics: Animals; Structure-Activity Relationship; Amino Acid Sequence; Fish Diseases; Antimicrobial Peptides; Fish Proteins; Disulfides; Phylogeny; Aeromonas hydrophila; Base Sequence
PubMed: 38835040
DOI: 10.1186/s12917-024-04106-8 -
Archives of Razi Institute Dec 2023The genus is a widespread pathogen that includes more than 30 Gram-negative species, many of which are opportunistic bacteria. Aeromonas species are naturally... (Review)
Review
The genus is a widespread pathogen that includes more than 30 Gram-negative species, many of which are opportunistic bacteria. Aeromonas species are naturally distributed in various aquatic sources. Infectious processes in marine animals such as fish usually develop under stressful conditions, and when their immune systems are weakened. MicroRNAs (miRNAs/miRs) are short, non-coding RNAs that post-transcriptionally regulate gene expression. Their diverse biological functions, such as influencing cell development, proliferation, differentiation, tumorigenesis, metabolism, and apoptosis have been studied in various animals. Fish is the most important source of aquatic nutrients throughout the world, and its market is constantly growing. Overpopulation in aquaculture brings infectious diseases that threaten the development of aquaculture around the world. There is extensive evidence that microRNAs are involved in modulating infectious processes and regulating the inflammatory response to major bacterial fish infections, including . Here, we review the current literature on the fish microRNA repertoire and outline the physiological roles assigned to microRNAs to provide a foundation for future research during infection. Understanding the interaction between microRNAs and may provide clues to a remarkable strategy for preventing infections in fish.
Topics: MicroRNAs; Animals; Aeromonas; Gram-Negative Bacterial Infections; Fish Diseases; Fishes
PubMed: 38828176
DOI: 10.32592/ARI.2023.78.6.1668 -
F1000Research 2023Strategies to increase body resistance and prevent disease in aquaculture include using vaccines, antibiotics, and probiotics. Today, the use of antibiotics with...
Strategies to increase body resistance and prevent disease in aquaculture include using vaccines, antibiotics, and probiotics. Today, the use of antibiotics with natural ingredients is becoming a trend. One of the natural ingredients that contain high antioxidants and antibiotics is sp. This research was conducted from March to May 2022 at the Biotechnology Laboratory, Faculty of Fisheries and Marine, Universitas Riau, in two stages: 1) the sensitivity of extracts of sp. and 2) the application of sp. extract orally in tilapia ( ). The parameters measured were clear zone, minimum inhibitory concentration, LD test of leaf extract of sp. in tilapia ( ), hemoglobin levels, hematocrit, total leukocytes, total erythrocytes, leukocyte differentiation, and survival rate. Data on hematology parameters were tabulated and analyzed using a One-Way ANOVA followed by a Student Newman Keuls (SNK) test when deemed necessary. The results showed that the extract of sp. inhibited the growth of bacteria with a clear zone of 6.5-15.0 mm, which is classified as resistant. At doses of 2000, 2500, and 3000 ppm, it did not cause death in fish for 96 hours (LD ). Hematological parameters can be a sign of the health status of fish. Tilapia given sp. in different doses gave an effect between treatments, both after 30 days of rearing and post-test against bacteria (p<0.05). The results showed that the hematology of fish fed with sp. extract was in the normal or healthy range. Healthy tilapia had erythrocyte counts ranging from 1.34-2.11×10 cells/mm , hematocrit 26.17-33.19%, hemoglobin 6.26-11.2 g/dL and total leukocytes 1.01-1.50×10 cells/mm and total erythrocytes 5.88-9.13×10 cells/ mm . A dose of 3000 ppm provided the highest health improvement against bacterial infection.
Topics: Animals; Sargassum; Cichlids; Aeromonas hydrophila; Microbial Sensitivity Tests; Anti-Bacterial Agents; Fish Diseases
PubMed: 38817412
DOI: 10.12688/f1000research.128819.2 -
Microbial Genomics May 2024is an emerging human enteric pathogen. However, the genomic features and virulence genes of strains from human gastroenteritis and other sources have not been fully...
Analysis of global genomes revealed that strains carrying T6SS are more common in human gastroenteritis than in environmental sources and are often phylogenetically related.
is an emerging human enteric pathogen. However, the genomic features and virulence genes of strains from human gastroenteritis and other sources have not been fully elucidated. Here, we conducted a genomic analysis of 565 global strains isolated from different sources, including 261 strains isolated from faecal samples of gastroenteritis patients, of which 18 genomes were sequenced in this study. The presence of bacterial virulence genes and secretion systems in strains from different sources was compared, and the phylogenetic relationship of strains was assessed based on the core genome. The complete genome of strain A20-9 isolated from a gastroenteritis patient was obtained in this study, from which 300 putative virulence factors and a T4SS-encoding plasmid, pAC, were identified. Genes encoding T4SS were also identified in a novel genomic island, ACI-1, from other T4SS-positive strains. The prevalence of T4SS was significantly lower in strains from gastroenteritis patients than in environmental strains (3 %, <0.0001 vs 14 %, <0.01). Conversely, the prevalence of T6SS was significantly higher in strains isolated from gastroenteritis patients than in environmental strains (25 %, <0.05 vs 13 %, <0.01). Four phylogenetic clusters were formed based on the core genome of 565 . strains, and strains carrying T6SS often showed close phylogenetic relationships. T3SS, aerolysin and thermostable cytotonic enterotoxin were absent in all 565 . strains. Our findings provide novel information on the genomic features of and suggest that T6SS may play a role in -induced human gastroenteritis.
Topics: Gastroenteritis; Humans; Phylogeny; Genome, Bacterial; Aeromonas caviae; Virulence Factors; Type VI Secretion Systems; Feces; Gram-Negative Bacterial Infections; Genomic Islands; Plasmids
PubMed: 38814176
DOI: 10.1099/mgen.0.001258 -
BMC Veterinary Research May 2024Moringa oleifera, a well-known medicinal plant, has been used in aquafeed as a dietary supplement. Based on previous studies, insufficient research is available on the...
Immunomodulatory, antioxidant, and growth-promoting activities of dietary fermented Moringa oleifera in Nile tilapia (Oreochromus niloticus) with in-vivo protection against Aeromonas hydrophila.
BACKGROUND
Moringa oleifera, a well-known medicinal plant, has been used in aquafeed as a dietary supplement. Based on previous studies, insufficient research is available on the dietary supplementation of Nile tilapia with M. oleifera leaf and seed mixtures, specifically the fermented form. Therefore, this study aimed to investigate the efficacy of fermented (FMO) versus non-fermented M. oleifera (MO) leaf and seed mixtures on immunological parameters, antioxidant activity, growth performance, and resistance to A. hydrophila infection after a 30-day feeding trial on Nile tilapia.
METHODS
A total of 180 fingerlings were randomly divided into four groups in addition to the control group (36 fish each, in triplicate). Fish in the tested groups were fed on basal diet supplemented with MO5%, MO10%, FMO5%, and FMO10%, while those in control were fed on basal diet only. After the feeding trial, fish were challenged with A. hydrophila. The immunomodulatory activity of M. oleifera was evaluated in terms of phagocytic and lysozyme activities, immune-related cytokines and IgM gene expression. Antioxidants, and growth-promoting activities were also assessed.
RESULTS
The results revealed that fish supplemented FMO markedly in FMO10% group followed by FMO5%, exhibited significant (P < 0.05) improvement in the tested immunological, hepatic antioxidants, and growth performance parameters. Furthermore, the highest survival rate post-challenge with mild clinical symptoms, and the lowest A. hydrophila bacterial count were reported in these groups. Meanwhile, MO10%-supplementation exhibited the opposite trend.
CONCLUSIONS
The study' conclusion suggests that fermented M. oleifera leaf and seed mixture is a promising growth-promoting and immunostimulatory feed-additive candidate for Nile tilapia and could reduce the losses caused by A. hydrophila infection.
Topics: Animals; Moringa oleifera; Aeromonas hydrophila; Cichlids; Gram-Negative Bacterial Infections; Antioxidants; Animal Feed; Fish Diseases; Diet; Dietary Supplements; Plant Leaves; Fermentation; Seeds
PubMed: 38802892
DOI: 10.1186/s12917-024-04070-3 -
Frontiers in Immunology 2024, a bacterium widely distributed in the natural environment, causes multiple diseases in various animals. Exploring the mechanism of the host defense against can help...
Integrated time-series biochemical, transcriptomic, and metabolomic analyses reveal key metabolites and signaling pathways in the liver of the Chinese soft-shelled turtle () against infection.
INTRODUCTION
, a bacterium widely distributed in the natural environment, causes multiple diseases in various animals. Exploring the mechanism of the host defense against can help develop efficient strategies against infection.
METHODS
Herein, we investigated the temporal influence of A. hydrophila on the Chinese soft-shelled turtle, an economically important species, at the biochemical, transcriptomic, and metabolomic levels. Plasma parameters were detected with the test kits. Transcriptome and metabolome were respectively applied to screen the differentially expressed genes and metabolites.
RESULTS
The contents or activities of these plasma parameters were significantly increased at 24 hpi and declined at 96 hpi, indicating that 24 and 96 hpi were two important time points during infection. Totals of 3121 and 274 differentially expressed genes (DEGs) from the transcriptome while 74 and 91 differentially abundant metabolites (DAMs) from the metabolome were detected at 24 and 96 hpi. The top DEGs at 24 hpi included and while and were the most abundant at 96 hpi. The predominant DAMs included O-phospho-L-serine, γ-Aminobutyric acid, orotate, L-tyrosine, and L-tryptophan at 24 hpi, as well as L-glutamic acid, L-arginine, glutathione, glutathione disulfide, and citric acid at 96 hpi.
DISCUSSION
The combined analysis of DEGs and DAMs revealed that tryptophan metabolism, nicotinate and nicotinamide metabolism, as well as starch and sucrose metabolism, were the most important signaling pathways at the early infective stage while tyrosine metabolism, pyrimidine metabolism, as well as alanine, aspartate and glutamate metabolism were the most crucial pathways at the later stage. In general, our results indicated that the Chinese soft-shelled turtle displays stage-specific physiological responses to resist infection.
Topics: Animals; Turtles; Aeromonas hydrophila; Gram-Negative Bacterial Infections; Signal Transduction; Metabolomics; Liver; Metabolome; Transcriptome; Gene Expression Profiling
PubMed: 38799475
DOI: 10.3389/fimmu.2024.1376860 -
International Journal of Molecular... May 2024can be a substantial concern, as it causes various diseases in aquaculture. An effective and green method for inhibiting is urgently required. Emodin, a naturally...
can be a substantial concern, as it causes various diseases in aquaculture. An effective and green method for inhibiting is urgently required. Emodin, a naturally occurring anthraquinone compound, was exploited as a photo-antimicrobial agent against . At the minimum inhibitory concentration of emodin (256 mg/L) to inactivate in 30 min, an 11.32% survival rate was observed under 45 W white compact fluorescent light irradiation. In addition, the antibacterial activity under natural sunlight (0.78%) indicated its potential for practical application. Morphological observations demonstrated that the cell walls and membranes of were susceptible to damage by emodin when exposed to light irradiation. More importantly, the photoinactivation of was predominantly attributed to the hydroxyl radicals and superoxide radicals produced by emodin, according to the trapping experiment and electron spin resonance spectroscopy. Finally, a light-dependent reactive oxygen species punching mechanism of emodin to photoinactivate was proposed. This study highlights the potential use of emodin in sunlight-mediated applications for bacterial control, thereby providing new possibilities for the use of Chinese herbal medicine in aquatic diseases prevention.
Topics: Emodin; Aeromonas hydrophila; Sunlight; Anti-Bacterial Agents; Microbial Sensitivity Tests; Reactive Oxygen Species
PubMed: 38791482
DOI: 10.3390/ijms25105444