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Fish & Shellfish Immunology Nov 2023GSDMs could punch holes in cell membrane and participate in the immune response to bacterial infections. In current study, the molecular and structural characteristics...
GSDMs could punch holes in cell membrane and participate in the immune response to bacterial infections. In current study, the molecular and structural characteristics of CcGSDMEa-like were analyzed, and the role of CcGSDMEa-like in the inflammatory response against Aeromonas hydrophila was studied. The results showed that the CcGSDMEa-like shared the conserved structural characteristics with GSDMEs of other teleosts. The CcGSDMEa-like mRNA and protein expression levels were significantly affected by A. hydrophila challenge. When the CcGSDMEa-like was overexpressed, the expression of CcIL-1β were significantly increased in fish and EPC cells, and bacterial contents were significantly decreased in fish tissues. While, when the CcGSDMEa-like was knocked down, the expression and secretion of CcIL-1β were significantly decreased in vivo and in vitro, and the bacterial contents were increased in vivo after A. hydrophila infection 12 h and 24 h. In brief, CcGSDMEa-like could regulate the content of bacteria in fish through mediating the expression and secretion of CcIL-1β. Bactericidal assay and cytotoxicity assay showed that CcGSDMEa-like had no bactericidal activity to Escherichia coli, and did not disrupt cytomembrane integrity of HEK293T cells. This study suggested that CcGSDMEa-like could play roles in the antibacterial and inflammatory processes in fish.
Topics: Humans; Animals; Carps; Aeromonas hydrophila; HEK293 Cells; Gram-Negative Bacterial Infections; Anti-Bacterial Agents; Fish Diseases; Fish Proteins; Immunity, Innate
PubMed: 37741476
DOI: 10.1016/j.fsi.2023.109103 -
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 Pathogenesis Oct 2023Aeromonas veronii is a common bacterium found in a variety of aquatic environments, capable of causing a diverse array of diseases in both aquatic animals and humans....
Aeromonas veronii is a common bacterium found in a variety of aquatic environments, capable of causing a diverse array of diseases in both aquatic animals and humans. Therefore, evaluating the pathogenicity of A. veronii and implementing measures to control its spread are essential. In this study, a strain JW-4, identified as A. veronii, was isolated from diseased Scaphesthes macrolepis, a grade Ⅱ protected animal in China. To investigate the pathogenicity of the strain, fish were fed with serial levels JW-4 supplemented diet or basal diet (control group 1, CG) for 28 days (d). Results showed that JW-4 stimulated an immune response, evidenced by an increase in immune-related enzyme activities (GOT and GPT) of serum and liver and an upregulation of genes expression levels (TNF-α and IFN-γ) of liver and spleen, and these effects gradually decreased over time. Histopathological examination revealed that JW-4 could alter the tissue structure of immune organs, such as liver and kidney. These changes were accompanied by vacuolar degeneration, nuclear dissolution, and an increased lymphocyte count. To assess protective effects of a vaccine against this strain, fish were injected with an inactivated vaccine (immunization group, IG) or 0.85% sterile saline (control group 2, CG) for 28-day observation period, then challenged with JW-4 on the 28th day. The inactivated vaccine enhanced total and specific IgM to A. veronii levels of the fish, resulting in a relative percentage survival of 75% in IG. These findings provide a foundation for identifying pathogenic bacteria and developing more effective prophylactic strategies in aquaculture.
Topics: Animals; Humans; Carps; Vaccines, Inactivated; Aeromonas veronii; Virulence; Liver
PubMed: 37611778
DOI: 10.1016/j.micpath.2023.106315 -
Journal of Fish Diseases Nov 2023This study explored the bactericidal role of the epidermal mucus (EM) of five freshwater Cyprinid fish species namely Ctenopharyngodon idella, Labeo rohita, Catla catla,...
This study explored the bactericidal role of the epidermal mucus (EM) of five freshwater Cyprinid fish species namely Ctenopharyngodon idella, Labeo rohita, Catla catla, Hypophthalmichthys molitrix, and Cirrhinus mrigala after treatment with Aeromonas hydrophila. Extracts of EM (crude and acidic) of each species showed bactericidal activity against various Gram -ve (Pseudomonas aeruginosa, Escherichia coli, Aeromonas hydrophila, Edwardsiella tarda, Salmonella enterica, Klebsiella pneumonia, Serratia marcescens, and Enterobacter cloacae) and Gram +ve (Bacillus wiedmannii and Staphylococcus aureus) bacteria compared with standard antibiotics (Fosfomycin). The zone of inhibition (ZOI) was measured in millimetres against antibiotics (Fosfomycin). Variations in bactericidal activity of EM were observed against bacteria from the same and different fish species. The acidic extract was more effective than the crude extract and showed significantly higher ZOI values against various bacteria and Fosfomycin antibiotics. This result shows that fish EM may perform an important role in fish defence against bacteria. Therefore, this study may hint towards the substitution of synthetic antibiotics with fish EM that may be used as a novel 'bactericidal' in aquaculture as well as in humans against bacterial infections.
Topics: Humans; Animals; Aeromonas hydrophila; Fosfomycin; Fish Diseases; Carps; Cyprinidae; Bacteria; Anti-Bacterial Agents; Mucus
PubMed: 37501533
DOI: 10.1111/jfd.13841 -
Fish & Shellfish Immunology May 2024This study investigated the benefits of yeast, Saccharomyces cerevisiae and/or garlic, Allium sativum supplementation in diets of Nile tilapia with regard to growth,...
Dietary effects of Saccharomyces cerevisiae and Allium sativum on growth, antioxidant status, hepatic and intestinal histoarchitecture, expression of growth- and immune-related genes, and resistance of Oreochromis niloticus to Aeromonas sobria.
This study investigated the benefits of yeast, Saccharomyces cerevisiae and/or garlic, Allium sativum supplementation in diets of Nile tilapia with regard to growth, antioxidant status, hepatic and intestinal histoarchitecture, expression of growth- and immune-related genes, and resistance to Aeromonas sobria infection. Fish (with an initial weight of 9.43 ± 0.08 g) were allocated to twelve hapas, organized into four triplicate treatment groups defined as control (no supplementation), yeast (4 g/kg diet), garlic (30 g/kg diet), and a mixture of both. This trial continued over a 60-day feeding period. Results revealed that combined treatment (yeast + garlic) demonstrated the most promising outcomes regarding growth, with significantly higher final body weights, weight gains, and specific growth rates compared to other groups. Moreover, this combination enhanced hepatic antioxidant status, as evidenced by elevated levels of reduced glutathione and activities of catalase and superoxide dismutase enzymes, reflecting improved defense against oxidative stress. Histological assessments of the livers and intestines demonstrated structural enhancements in yeast and garlic treatments, suggesting improvements in organ health. In comparison to the control, the gene expression analyses unveiled increased expression of growth-related (igf-1 and ghr1) and immune-related (il-10, lyz, and hep) genes in the test groups, indicating a possible reinforcement of the growth and immune responses. The combined treatment also showed the highest resistance to A. sobria infection, as evidenced by improved survival rates and lower mortality compared with the other groups. These findings highlight the benefits of a combination of both yeast and garlic as a dietary supplementation regimen. In conclusion, this study suggests that the combined treatment regimen could be considered an effective strategy to promote the health and productivity of Nile tilapia under production conditions.
Topics: Animals; Antioxidants; Garlic; Saccharomyces cerevisiae; Dietary Supplements; Cichlids; Diet; Liver; Intestines; Animal Feed; Fish Diseases; Disease Resistance; Aeromonas
PubMed: 38461877
DOI: 10.1016/j.fsi.2024.109493 -
Critical Reviews in Microbiology Sep 2023The genus comprises Gram-negative bacilli widely distributed in aquatic habitats that can also be found in the terrestrial environment and in close association with...
The genus comprises Gram-negative bacilli widely distributed in aquatic habitats that can also be found in the terrestrial environment and in close association with humans and animals. spp. are particularly versatile bacteria, with high genomic plasticity and notable capacity to adapt to different environments and extreme conditions. On account of being mostly associated with their pathogenic potential, research on the biotechnological potentialities of spp. is considerably scarce when compared to other bacterial groups. Nonetheless, studies over the years have been hinting at several interesting hidden potentialities in this bacterial group, especially with the recent advances in whole-genome sequencing, unveiling spp. as interesting candidates for the discovery of novel industrial biocatalysts, bioremediation strategies, and biopolyester production. In this context, the present study aims to provide an overview of the main biotechnological applications reported in the genus and provide new insights into the further exploration of these frequently overlooked, yet fascinating, bacteria.
Topics: Humans; Animals; Aeromonas; Biotechnology
PubMed: 35687715
DOI: 10.1080/1040841X.2022.2083940 -
Brazilian Journal of Microbiology :... Sep 2023N-Acetyl-glucosaminidases (GlcNAcases) are exoenzymes found in a wide range of living organisms, which have gained great attention in the treatment of disorders related...
N-Acetyl-glucosaminidases (GlcNAcases) are exoenzymes found in a wide range of living organisms, which have gained great attention in the treatment of disorders related to diabetes, Alzheimer's, Tay-Sachs', and Sandhoff's diseases; the control of phytopathogens; and the synthesis of bioactive GlcNAc-containing products. Aiming at future industrial applications, in this study, GlcNAcase production by marine Aeromonas caviae CHZ306 was enhanced first in shake flasks in terms of medium composition and then in bench-scale stirred-tank bioreactor in terms of physicochemical conditions. Stoichiometric balance between the bioavailability of carbon and nitrogen in the formulated culture medium, as well as the use of additional carbon and nitrogen sources, played a central role in improving the bioprocess, considerably increasing the enzyme productivity. The optimal cultivation medium was composed of colloidal α-chitin, corn steep liquor, peptone A, and mineral salts, in a 5.2 C:N ratio. Optimization of pH, temperature, colloidal α-chitin concentration, and ka conditions further increased GlcNAcase productivity. Under optimized conditions in bioreactor (i.e., 34 °C, pH 8 and ka 55.2 h), GlcNAcase activity achieved 173.4 U.L after 12 h of cultivation, and productivity no less than 14.45 U.L.h corresponding to a 370-fold enhancement compared to basal conditions.
Topics: Aeromonas caviae; Bioreactors; Carbon; Chitin; Hexosaminidases; Nitrogen
PubMed: 37610567
DOI: 10.1007/s42770-023-01088-x -
Fish & Shellfish Immunology Feb 2024Nile tilapia reared under intensive conditions was more susceptible for Ichthyophthirius multifilii (I. multifiliis) infection eliciting higher mortality, lower...
Chlorella vulgaris extract conjugated magnetic iron nanoparticles in nile tilapia (Oreochromis niloticus): Growth promoting, immunostimulant and antioxidant role and combating against the synergistic infection with Ichthyophthirius multifiliis and Aeromonashydrophila.
Nile tilapia reared under intensive conditions was more susceptible for Ichthyophthirius multifilii (I. multifiliis) infection eliciting higher mortality, lower productive rate and further bacterial coinfection with Aeromonas hydrophila (A. hydrophila). The higher potency of magnetic field of iron oxide nanoparticles (NPs) can kill pathogens through inhibiting their viability. Herein, coating of Chlorella vulgaris extract (ChVE) with magnetic iron oxide NPs (Mag iron NPs) can create an external magnetic field that facilitates their release inside the targeted tissues. Thus, the current study is focused on application of new functionalized properties of Mag iron NPs in combination with ChVE and their efficacy to alleviate I. multifiliis and subsequent infection with A. hydrophila in Nile tilapia. Four hundred fingerlings were divided into: control group (with no additives), three groups fed control diet supplemented with ChVE, Mag iron NPs and ChVE@Mag iron NPs for 90 days. At the end of feeding trial fish were challenged with I. multifiliis and at 9 days post challenge was coinfected by A. hydrophila. A remarkable higher growth rate and an improved feed conversion ratio were detected in group fed ChVE@Mag iron-NPs. The maximum expression of antioxidant enzymes in skin and gills tissues (GSH-Px, CAT, and SOD) which came in parallel with higher serum activities of these enzymes was identified in groups received ChVE@Mag iron-NPs. Furthermore, group fed a combination of ChVE and Mag iron-NPs showed a boosted immune response (higher lysozyme, IgM, ACH, and MPO) prior to challenge with I. multifiliis. In contrast, fish fed ChVE@Mag iron-NPs supplemented diet had lower infection (decreased by 62%) and mortality rates (decreased by 84%), as well as less visible white spots (decreased by 92 % at 12 dpi) on the body surfaces and mucous score. Interestingly, post I. multifiliis the excessive inflammatory response in gill and skin tissues was subsided by feeding on ChVE@Mag iron-NPs as proved by down regulation of IL-1β, TNFα, COX-2 and iNOS and upregulation of IL-10, and IgM, IgT and Muc-2 genes. Notably, group exposed to I. multifiliis-showed higher mortality when exposed to Aeromonas hydrophilia (increased by 43 %) while group fed ChVE@Mag iron-NPs exhibited lower morality (2%). Moreover, the bacterial loads of A. hydrophilia in fish infected by I. multifiliis and fed control diet were higher than those received dietary supplement of ChVE, Mag iron-NPs and the most reduced load was obtained in group fed ChVE@Mag iron-NPs at 7 dpi. In conclusion, ChVE@Mag iron-NPs fed fish had stronger immune barrier and antioxidant functions of skin and gills, and better survival following I. multifiliis and A. hydrophilia infection.
Topics: Animals; Antioxidants; Cichlids; Chlorella vulgaris; Adjuvants, Immunologic; Dietary Supplements; Diet; Aeromonas hydrophila; Magnetic Iron Oxide Nanoparticles; Immunoglobulin M; Iron; Animal Feed; Fish Diseases; Disease Resistance
PubMed: 38171430
DOI: 10.1016/j.fsi.2023.109352 -
Food Research International (Ottawa,... Jan 2024Aeromonas sp. is a Gram-negative, non-spore-forming, rod-shaped, oxidase-positive, facultative anaerobic bacterium and a natural contaminant found in aquatic... (Review)
Review
Aeromonas sp. is a Gram-negative, non-spore-forming, rod-shaped, oxidase-positive, facultative anaerobic bacterium and a natural contaminant found in aquatic environments. Some species can invade, colonize, and damage host cells due to the presence of virulence factors, such as flagella, elastase, hemolysins, aerolysins, adhesins, enterotoxins, phospholipases and lipases, that lead to pathogenic activities. Consequently, can cause many health disorders that range from gastrointestinal problems, enteric infections, and ulcers to hemorrhagic septicemia. Aeromonas has been isolated and identified from a variety of sources, including drinking water and ready-to-eat foods (fish, meat, fresh vegetables, dairy products, and others). Some species of this opportunistic pathogen are resistant to several commercial antibiotics, including some used as a last resort for treatment, which represents a major challenge in the clinical segment. Antimicrobial resistance can be attributed to the indiscriminate use of antibiotics by society in aquaculture and horticulture. In addition, antibiotic resistance is attributed to plasmid transfer between microorganisms and horizontal gene transfer. This review aimed to (i) verify the occurrence of Aeromonas species in water and food intended for human consumption; (ii) identify the methods used to detect Aeromonas species; (iii) report on the virulence genes carried by different species; and (iv) report on the antimicrobial resistance of this genus in the last 5 years of research. Additionally, we present the existence of Aeromonas spp. resistant to antimicrobials in food and drinking water represents a potential threat to public health.
Topics: Animals; Humans; Aeromonas; Virulence; Anti-Bacterial Agents; Drinking Water; Base Composition; Drug Resistance, Bacterial; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Anti-Infective Agents
PubMed: 38128981
DOI: 10.1016/j.foodres.2023.113710 -
Journal of Applied Microbiology Apr 2024Although elasmobranchs are consumed worldwide, bacteriological assessments for this group are still sorely lacking. In this context, this study assessed bacteria of...
AIMS
Although elasmobranchs are consumed worldwide, bacteriological assessments for this group are still sorely lacking. In this context, this study assessed bacteria of sharks and rays from one of the most important landing ports along the Rio de Janeiro coast.
METHODS AND RESULTS
Bacteria were isolated from the cloacal swabs of the sampled elasmobranchs. They were cultured, and Vibrio, Aeromonas, and Enterobacterales were isolated and identified. The isolated bacteria were then biochemically identified and antimicrobial susceptibility assays were performed. Antigenic characterizations were performed for Salmonella spp. and Polymerase Chain Reaction (PCR) assays were performed to identify Escherichia coli pathotypes. Several bacteria of interest in the One Health context were detected. The most prevalent Enterobacterales were Morganella morganii and Citrobacter freundii, while Vibrio harveyi and Vibrio fluvialis were the most prevalent among Vibrio spp. and Aeromonas allosacharophila and Aeromonas veronii bv. veronii were the most frequent among Aeromonas spp. Several bacteria also displayed antimicrobial resistance, indicative of Public Health concerns. A total of 10% of Vibrio strains were resistant to trimethoprim-sulfamethoxazole and 40% displayed intermediate resistance to cefoxitin. Salmonella enterica strains displayed intermediate resistance to ciprofloxacin, nalidixic acid and streptomycin. All V. cholerae strains were identified as non-O1/non-O139. The detected E. coli strains did not exhibit pathogenicity genes. This is the first study to perform serology assessments for S. enterica subsp. enterica isolated from elasmobranchs, identifying the zoonotic Typhimurium serovar. Salmonella serology evaluations are, therefore, paramount to identify the importance of elasmobranchs in the epidemiological salmonellosis chain.
CONCLUSIONS
The detection of several pathogenic and antibiotic-resistant bacteria may pose significant Public Health risks in Brazil, due to high elasmobranch consumption rates, indicating the urgent need for further bacteriological assessments in this group.
Topics: Animals; Escherichia coli; Sharks; Brazil; Salmonella; Vibrio cholerae; Anti-Bacterial Agents; Aeromonas
PubMed: 38486350
DOI: 10.1093/jambio/lxae068