Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.512
Filtrar
1.
Braz. j. biol ; 84: e254816, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355894

RESUMO

Abstract Pakistan is an agricultural country and fisheries play a very important role in the economic development of the country. Different diseases are prevalent in Pakistani fish but information related to the causative agents is not well-known. Keeping in view the significance of bacterial pathogens as the causative agents of multiple fish diseases, the present study was conducted for identification, characterization and analysis of virulence genes of Aeromonas spp. isolated from diseased fishes. A total of fifty fish samples having multiple clinical indications were collected from different fish farms of district Kasur, Punjab Pakistan. For isolation of Aeromonas spp. samples were enriched and inoculated on Aeromonas isolation medium. Isolates were identified and characterized by different biochemical tests, Analytical Profile Index (API) 20E kit and Polymerase Chain Reaction (PCR) assays. All isolates were screened for three putative virulence genes including aerolysin (aer), haemolysin (hyl) and heat labile cytotonic enterotoxin (alt). Seven isolates of Aeromonas (A.) hydrophila were retrieved and identified based on API 20E. These isolates were further confirmed as A. hydrophila on the basis of PCR assays. Three isolates were detected positive for the presence of virulence genes (alt and hyl). Whereas aerolysin (aer) gene was not present in any of A. hydrophila isolates. The present study confirmed A. hydrophila as the causative agent of epizootic ulcerative syndrome and motile Aeromonas septicemia in fish farms of district Kasur, Punjab Pakistan. Moreover, detection of two virulence genes (alt and hyl) in A. hydrophila isolates is a threat for fish consumers of study area.


Resumo O Paquistão é um país agrícola, onde a pesca desempenha um papel muito importante para o desenvolvimento econômico. Diferentes doenças são prevalentes em peixes do Paquistão, mas as informações relacionadas aos agentes causadores não são bem conhecidas. Tendo em vista a importância dos patógenos bacterianos como agentes causadores de múltiplas doenças em peixes, o presente estudo foi conduzido para identificação, caracterização e análise de genes de virulência de isolados de Aeromonas spp. de peixes doentes. Foram coletadas 50 amostras de peixes com múltiplas indicações clínicas em diferentes fazendas do distrito de Kasur, Punjab, Paquistão. Para isolar Aeromonas spp., as amostras foram enriquecidas e inoculadas em meio de isolamento. Os isolados foram identificados e caracterizados por diferentes testes bioquímicos, kit Analytical Profile Index (API) 20E, e ensaios de reação em cadeia da polimerase (PCR). Todos os isolados foram selecionados para três genes de virulência putativos, incluindo aerolisina (aer), hemolisina (hyl) e enterotoxina citotônica termolábil (alt). Sete isolados de Aeromonas hydrophila foram recuperados e identificados com base no API 20E. Esses isolados foram posteriormente confirmados como A. hydrophila de acordo com ensaios de PCR. Três isolados indicaram a presença de genes de virulência (alt e hyl), enquanto o gene aerolisina (aer) não esteve presente em nenhum dos isolados de A. hydrophila. O presente estudo confirmou A. hydrophila como o agente causador da síndrome ulcerativa epizoótica e septicemia móvel por Aeromonas em fazendas de peixes, no distrito de Kasur, Punjab, Paquistão. Além disso, a detecção de dois genes de virulência (alt e hyl) em isolados de A. hydrophila é uma ameaça para os consumidores de peixes da área de estudo.


Assuntos
Animais , Infecções por Bactérias Gram-Negativas/veterinária , Infecções por Bactérias Gram-Negativas/epidemiologia , Aeromonas/genética , Paquistão , Aeromonas hydrophila/genética , Enterotoxinas/genética , Peixes
2.
Braz. j. biol ; 83: e249913, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339352

RESUMO

Abstract Aeromonas hydrophila is a cause of infectious disease outbreaks in carp species cultured in South Asian countries including Pakistan. This bacterium has gained resistance to a wide range of antibiotics and robust preventive measures are necessary to control its spread. No prior use of fish vaccines has been reported in Pakistan. The present study aims to develop and evaluate inactivated vaccines against local strain of A. hydrophila in Pakistan with alum-precipitate as adjuvant. The immunogenic potential of vaccine was evaluated in two Indian major carps (Rohu: Labeo rohita, Mori: Cirrhinus mrigala) and a Chinese carp (Grass carp: Ctenopharyngodon idella). Fish were vaccinated intraperitoneally followed by a challenge through immersion. Fish with an average age of 4-5 months were randomly distributed in three vaccinated groups with three vaccine concentrations of 108, 109 and 1010 colony forming unit (CFU)/ml and a control group. Fixed dose of 0.1ml was applied to each fish on 1st day and a booster dose at 15 days post-vaccination (DPV). Blood samples were collected on 14, 28, 35, 48 and 60 DPV to determine antibody titers in blood serum using compliment fixation test (CFT). Fish were challenged at 60 DPV with infectious A. hydrophila with 108 CFU/ml through immersion. Significantly higher levels of antibody titers were observed from 28 DPV in all vaccinated groups as compared to those in the control group. In challenge experiment the average RPS (relative percent survivability) was 71% for groups vaccinated with 109 and 1010 CFU/ml and 86% for 108 CFU/ml. Vaccine with 108 CFU/ml induced highest immune response followed by 109 and 1010 CFU/ml. The immune response of L. rohita and C. idella was better than that of C. mrigala. In general, normal histopathology was observed in different organs of vaccinated fish whereas minor deteriorative changes were found in fish vaccinated with higher concentrations of the vaccine.


Resumo Aeromonas hydrophila é uma causa de surtos de doenças infecciosas em espécies de carpas cultivadas em países do sul da Ásia, incluindo o Paquistão. Essa bactéria ganhou resistência a uma ampla gama de antibióticos, e medidas preventivas robustas são necessárias para controlar sua disseminação. Nenhum uso anterior de vacinas para peixes foi relatado no Paquistão. O presente estudo tem como objetivo desenvolver e avaliar vacinas inativadas contra cepa local de A. hydrophila no Paquistão com precipitado de alúmen como adjuvante. O potencial imunogênico da vacina foi avaliado em duas carpas principais indianas (Rohu: Labeo rohita, Mori: Cirrhinus mrigala) e uma carpa chinesa (Grass Carp: Ctenopharyngodon idella). Os peixes foram vacinados por via intraperitoneal, seguido de um desafio por imersão. Peixes com idade média de 4-5 meses foram distribuídos aleatoriamente em três grupos vacinados com três concentrações de vacina de 108, 109 e 1010 unidades formadoras de colônias (UFC) / ml e um grupo de controle. Foi aplicada dose fixa de 0,1ml em cada peixe no 1º dia e dose de reforço 15 dias pós-vacinação (DPV). Amostras de sangue foram coletadas em 14, 28, 35, 48 e 60 DPV para determinar os títulos de anticorpos no soro sanguíneo usando o teste de fixação de elogio (CFT). Os peixes foram desafiados a 60 DPV com infecciosa A. hydrophila com 108 CFU / ml por imersão. Níveis significativamente mais elevados de títulos de anticorpos foram observados em 28 DPV em todos os grupos vacinados, em comparação com aqueles no grupo de controle. Na experiência de desafio, o RPS médio (sobrevivência percentual relativa) foi de 71% para os grupos vacinados com 109 e 1010 CFU / ml e 86% para 108 CFU / ml. A vacina com 108 UFC / ml induziu a maior resposta imune seguida por 109 e 1010 UFC / ml. A resposta imune de L. rohita e C. idella foi melhor do que a de C. mrigala. Em geral, histopatologia normal foi observada em diferentes órgãos de peixes vacinados, enquanto pequenas alterações deteriorantes foram encontradas no grupo de controle e nos peixes vacinados com concentrações mais altas da vacina.


Assuntos
Animais , Carpas , Infecções por Bactérias Gram-Negativas/prevenção & controle , Infecções por Bactérias Gram-Negativas/veterinária , Doenças dos Peixes/prevenção & controle , Vacinas Bacterianas , Aeromonas hydrophila , Compostos de Alúmen , Imersão
3.
Front Immunol ; 13: 863657, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35784342

RESUMO

Mannan oligosaccharides (MOS) have been studied and applied as a feed additive, whereas their regulation on the growth performance and immunity of aquatic animals lacks consensus. Furthermore, their immunoprotective effects on the freshwater fish Megalobrama amblycephala have not been sufficiently studied. Thus, we investigated the effects of dietary MOS of 0, 200, and 400 mg/kg on the growth performance, non-specific immunity, intestinal health, and resistance to Aeromonas hydrophila infection in juvenile M. amblycephala. The results showed that the weight gain rate of juvenile M. amblycephala was not significantly different after 8 weeks of feeding, whereas the feed conversion ratio decreased in the MOS group of 400 mg/kg. Moreover, dietary MOS increased the survival rate of juvenile M. amblycephala upon infection, which may be attributed to enhanced host immunity. For instance, dietary MOS increase host bactericidal and antioxidative abilities by regulating the activities of hepatic antimicrobial and antioxidant enzymes. In addition, MOS supplementation increased the number of intestinal goblet cells, and the intestine was protected from necrosis of the intestinal folds and disruption of the microvilli and junctional complexes, thus maintaining the stability of the intestinal epithelial barrier. The expression levels of M. amblycephala immune and tight junction-related genes increased after feeding dietary MOS for 8 weeks. However, the upregulated expression of immune and tight junction-related genes in the MOS supplemental groups was not as notable as that in the control group postinfection. Therefore, MOS supplementation might suppress the damage caused by excessive intestinal inflammation. Furthermore, dietary MOS affected the richness and composition of the gut microbiota, which improved the gut health of juvenile M. amblycephala by increasing the relative abundance of beneficial gut microbiota. Briefly, dietary MOS exhibited significant immune protective effects to juvenile M. amblycephala, which is a functional feed additive and immunostimulant.


Assuntos
Cyprinidae , Cipriniformes , Aeromonas hydrophila , Animais , Antioxidantes/farmacologia , Cyprinidae/metabolismo , Cipriniformes/metabolismo , Imunidade Inata , Mananas/metabolismo , Mananas/farmacologia , Oligossacarídeos/metabolismo , Oligossacarídeos/farmacologia
4.
Front Immunol ; 13: 875689, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35874671

RESUMO

Aeromonas are autochthonous bacteria of aquatic environments that are considered to be emerging pathogens to humans, producing diarrhea, bacteremia, and wound infections. Genetic identification shows that 95.4% of the strains associated with clinical cases correspond to the species Aeromonas caviae (37.26%), Aeromonas dhakensis (23.49%), Aeromonas veronii (21.54%), and Aeromonas hydrophila (13.07%). However, few studies have investigated the human immune response against some Aeromonas spp. such as A. hydrophila, Aeromonas salmonicida, and A. veronii. The present study aimed to increase the knowledge about the innate human immune response against six Aeromonas species, using, for the first time, an in vitro infection model with the monocytic human cell line THP-1, and to evaluate the intracellular survival, the cell damage, and the expression of 11 immune-related genes (TLR4, TNF-α, CCL2, CCL20, JUN, RELA, BAX, TP53, CASP3, NLRP3, and IL-1ß). Transcriptional analysis showed an upregulated expression of a variety of the monocytic immune-related genes, with a variable response depending upon the Aeromonas species. The species that produced the highest cell damage, independently of the strain origin, coincidentally induced a higher expression of immune-related genes and corresponded to the more prevalent clinical species A. dhakensis, A. veronii, and A. caviae. Additionally, monocytic cells showed an overexpression of the apoptotic and pyroptotic genes involved in cell death after A. dhakensis, A. caviae, and Aeromonas media infection. However, the apoptosis route seemed to be the only way of producing cell damage and death in the case of the species Aeromonas piscicola and Aeromonas jandaei, while A. veronii apparently only used the pyroptosis route.


Assuntos
Aeromonas , Infecções por Bactérias Gram-Negativas , Aeromonas/genética , Aeromonas hydrophila , Linhagem Celular , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Imunidade
5.
Front Immunol ; 13: 931021, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35860264

RESUMO

Toll-like receptors (TLRs) are epitomized as the first line of defense against pathogens. Amongst TLRs, TLR22 is expressed in non-mammalian aquatic vertebrates, including fish. Using headkidney macrophages (HKM) of Clarias gariepinus, we reported the pro-apoptotic and microbicidal role of TLR22 in Aeromonas hydrophila infection. Mitochondria act as a central scaffold in the innate immune system. However, the precise molecular mechanisms underlying TLR22 signaling and mitochondrial involvement in A. hydrophila-pathogenesis remain unexplored in fish. The aim of the present study was to investigate the nexus between TLR22 and mitochondria in pro-apoptotic immune signaling circuitry in A. hydrophila-infected HKM. We report that TLR22-induced mitochondrial-Ca2+ [Ca2+]mt surge is imperative for mtROS production in A. hydrophila-infected HKM. Mitigating mtROS production enhanced intracellular bacterial replication implicating its anti-microbial role in A. hydrophila-pathogenesis. Enhanced mtROS triggers hif1a expression leading to prolonged chop expression. CHOP prompts mitochondrial unfolded protein response (UPRmt) leading to the enhanced expression of mitochondrial fission marker dnml1, implicating mitochondrial fission in A. hydrophila pathogenesis. Inhibition of mitochondrial fission reduced HKM apoptosis and increased the bacterial burden. Additionally, TLR22-mediated alterations in mitochondrial architecture impair mitochondrial function (ΔΨm loss and cytosolic accumulation of cyt c), which in turn activates caspase-9/caspase-3 axis in A. hydrophila-infected HKM. Based on these findings we conclude that TLR22 prompts mtROS generation, which activates the HIF-1α/CHOP signalosome triggering UPRmt-induced mitochondrial fragmentation culminating in caspase-9/-3-mediated HKM apoptosis and bacterial clearance.


Assuntos
Aeromonas hydrophila , Peixes-Gato , Animais , Caspase 9/metabolismo , Macrófagos , Dinâmica Mitocondrial , Receptores Toll-Like/metabolismo
6.
J Hazard Mater ; 436: 129268, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35739783

RESUMO

Ochratoxin A (OTA) is a common hazardous food contaminant that seriously endangers human and animal health. However, limited study is focused on aquatic animal. This research investigated the multiple biotoxicity of OTA on spleen (SP) and head kidney (HK) in grass carp and its related mechanism. Our data showed that, dietary supplemented with OTA above 1209 µg/kg caused histopathological damages by decreasing the number of lymphocytes and necrotizing renal parenchymal cells. Meanwhile, OTA caused oxidative damage and reduced the isoforms mRNAs transcripts of antioxidant enzymes (e.g., GPX1, GPX4, GSTO) partly due to suppressing NF-E2-related factor 2 (Nrf2). OTA triggered apoptosis through mitochondria and death receptor pathway potentially by p38 mitogen-activated protein kinase (p38MAPK) activation. Besides, OTA exacerbated inflammation by down-regulation of anti-inflammatory factor (e.g., IL-10, IL-4) and up-regulations of pro-inflammatory factors (e.g., TNF-α, IL-6), which could be ascribed to signaling meditation of Janus kinase / signal transducer and activator of transcription (JAK/STAT). Additionally, the safe upper limits of OTA were estimated to be 677.6 and 695.08 µg/kg based on the immune-related indexes (C3 contents in the SP and LZ activities in the HK, respectively). Our study has provided a wide insight for toxicological assessment of feed pollutant in aquatic animals.


Assuntos
Carpas , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Aeromonas hydrophila/metabolismo , Ração Animal/análise , Animais , Apoptose , Carpas/metabolismo , Dieta , Proteínas de Peixes/metabolismo , Humanos , Imunidade Inata , Ocratoxinas , Estresse Oxidativo
7.
J Proteome Res ; 21(7): 1707-1717, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35674493

RESUMO

In recent years, the intracellular mechanisms that contribute to antibiotic resistance have received increasing attention, and outer membrane vesicles (OMVs) have been reported to be related to antibiotic resistance in several Gram-negative bacterial species. However, the intrinsic molecular mechanisms and the form of such antibiotic resistance are still largely unknown. In this study, OMVs from an oxytetracycline (OXY) sensitive aquatic pathogen, Aeromonas hydrophila (OXY-S), were found with significantly increased OXY resistance. Interestingly, the OXY-resistant strain (OXY-R) had a more protective role in OXY resistance. Therefore, a DIA-based quantitative proteomics analysis was performed to compare the differential expression of OMV proteins between OXY-R (OMVsR) and OXY-S (OMVsS). The results showed that seven proteins increased and five proteins decreased in OMVsR vs OMVsS. A subsequent antibiotics susceptibility assay showed that the deletion of icd, rpsF, and iscS significantly increased OXY sensitivity. Moreover, the exogenous addition of the crude OMV fractions of overexpressed recombinant proteins in E. coli with rRpsF, rIcd, rIscS, rOmpA, rPepA, rFrdA, and rRplQ demonstrated that these proteins promoted the OXY resistance of A. hydrophila. Overall, our results indicate the important protective role of OMVs in antibiotic resistance in A. hydrophila and provide novel insights on bacterial antibiotic resistance mechanisms.


Assuntos
Aeromonas hydrophila , Oxitetraciclina , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Bactérias/metabolismo , Farmacorresistência Bacteriana , Escherichia coli/metabolismo , Oxitetraciclina/metabolismo , Proteômica/métodos
8.
BMC Microbiol ; 22(1): 167, 2022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-35761217

RESUMO

Usage of "probiotics" for treatment of food-borne pathogens associated diseases, makes a significant reduction in transmission of resistant bacteria, and antimicrobial resistance genes from aquaculture environments to humans. In this research, the authors aim to evaluate the immunomodulatory, and histological effects of two probiotic strains on the Zebrafish model. Fish models were treated with Lactobacillus delbrueckii (G2), Lactobacillus acidophilus (G3) and both probiotics (G4) and compared with the control group (G1) (only infected by pathogen and receiving no probiotic). Biometric tests, height, weight, and mortality rate of the fishes were assessed. Afterward, RT-PCR was conducted for bacterial existence of probiotic strains, and quantitative assessment of alterations in targeted immune genes. Subsequently, histological sampling was done for investigation of spatial distribution, and villus length in proximal, middle, and distal sections of intestinal tissues. Based on the results, G4 showed the highest gene expression for Lactobacillus acidophilus after 28 days (P < 0.05). G4 also showed an increase in the number of goblet cells and villus length in the middle and distal sections of intestinal tissue after 56 days. Furthermore, after 56 days, the highest number of intraepithelial cells was observed in the proximal sections of intestinal tissue in G4. G2 and G3 showed significant differences in comparison with G1 (P < 0.05). After 60 days, the highest gene expression for Lactobacillus bulgaricus was found in group treated with only this probiotic bacteria. The highest expression level of IL-1ß and TNF-α were found in G1. The highest survival rate was in the case of groups only treated with Lactobacillus bulgaricus (G2). To sum up, it seems that usage of probiotics for the improvement of public health and fisheries industries can be helpful.


Assuntos
Anti-Infecciosos , Lactobacillus delbrueckii , Probióticos , Aeromonas hydrophila , Animais , Lactobacillus acidophilus , Lactobacillus delbrueckii/genética , Probióticos/farmacologia , Peixe-Zebra/microbiologia
9.
Virulence ; 13(1): 794-807, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35499101

RESUMO

The immunogenicity of Aha1, an OMP of Aeromonas hydrophila mediating the adhesion of bacteria onto the mucosal surface of hosts has been established. In this study, recombinant vectors, pPG1 and pPG2, carrying a 1366 bp DNA fragment that was responsible for encoding the 49 kDa Aha1 from A. hydrophila were constructed, respectively, then electroporated into a probiotic strain Lactobacillus casei CC16 separately to generate two types of recombinants, L. casei-pPG1-Aha1 (Lc-pPG1-Aha1) and L. casei-pPG2-Aha1 (Lc-pPG2-Aha1). Subsequently, these were orally administered into common carps to examine their immunogenicity. The expression and localization of the expressed Aha1 protein relative to the carrier L. casei was validated via Western blotting, flow cytometry, and immune fluorescence separately. The recombinant vaccines produced were shown high efficacies, stimulated higher level of antibodies and AKP, ACP, SOD, LZM, C3, C4 in serum in hosts. Immune-related gene expressions of cytokines including IL-10, IL-1ß, TNF-α, IFN-γ in the livers, spleens, HK, and intestines were up-regulated significantly. Besides, a more potent phagocytosis response was observed in immunized fish, and higher survival rates were presented in common carps immunized with Lc-pPG1-Aha1 (60%) and Lc-pPG2-Aha1 (50%) after re-infection with virulent strain A. hydrophila. Moreover, the recombinant L. casei were shown a stronger propensity for survivability in the intestine in immunized fish. Taken together, the recombinant L. casei strains might be promising candidates for oral vaccination against A. hydrophila infections in common carps.


Assuntos
Carpas , Lactobacillus casei , Aeromonas hydrophila/genética , Animais , Vacinas Bacterianas/genética , Lactobacillus casei/genética , Vacinação
10.
Microb Pathog ; 167: 105572, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35561978

RESUMO

The protective effect of cinnamaldehyde on channel catfish infected by drug-resistant Aeromonas hydrophila CW strain was explored by observing the clinical signs and histopathology, measuring the cumulative mortality, serum biochemical and non-specific immune indicators, and intestinal microbiota in this study. The cumulative survival rate of the cinnamaldehyde within 14 days was significantly higher than that of the challenge group, which was 70% and 20%, respectively. Compared with the challenge group, the activities of lysozyme, superoxide dismutase, and glutathione peroxidase in the treatment group were increased, while there was no significant difference in catalase activity. Compared with the challenge group, the histopathology results showed that the injury of liver, spleen, and kidney was significantly alleviated after cinnamaldehyde treatment. The results of intestinal microbiota showed that the proportion of Proteobacteria in the challenge group was significantly increased, and the proportion of Aeromonas sp. reached 30% based on the analysis of species classification level. The composition of dominant species in the treatment group was similar to the control group. In conclusion, cinnamaldehyde increased the cumulative survival rate of channel catfish infected by A. hydrophila. It could protect channel catfish through improving the non-specific immune function of channel catfish, alleviating the pathological lesions of liver, spleen, kidney, and intestine, and maintaining the relative balance of the intestinal microbiota. Therefore, cinnamaldehyde could be a candidate drug for the treatment of A. hydrophila infection.


Assuntos
Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Ictaluridae , Acroleína/análogos & derivados , Aeromonas hydrophila , Animais , Doenças dos Peixes/microbiologia , Proteínas de Peixes , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/veterinária
11.
Fish Shellfish Immunol ; 125: 220-229, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35569779

RESUMO

The aim of the present study was to investigate the partial replacement of fish meal by Saccharomyces cerevisiae culture on growth performance, immunity, composition and function of intestinal microbiota and disease resistance in channel catfish (Ictalurus punctatus). Two equal nitrogen and energy diets were prepared including a basal diet (containing 10% fish meal, Control) and an experimental diet (replacing 20% of the fish meal of the basal diet with yeast culture, RFM). Channel catfish were fed with the diets for 12 weeks. The results showed that weight gain and condition factor were significantly increased, and FCR was significantly decreased in RFM group (P < 0.05). The gene expression of intestinal HIF1α was significantly increased in RFM group (P < 0.05), while the expressions of NF-κB in the intestine and liver were significantly decreased (P < 0.05). The relative abundance of Firmicutes tended to increase, and the Turicibacter had an upward trend (0.05 < P < 0.2). In addition, the survival rate of channel catfish was significantly increased in RFM group after challenged with Aeromonas veronii Hm091 and Aeromonas hydrophila NJ-1 (P < 0.05). Compared with intestinal microbiota of channel catfish of control group, intestinal microbiota of channel catfish of RFM group significantly increased the expression of HIF1α, and decreased the expression of IL-1ß and TNF-α (P < 0.05) in germ-free zebrafish. Intestinal microbiota induced by RFM diet also significantly increased disease resistance to Aeromonas veronii Hm091 and Aeromonas hydrophila NJ-1. In conclusion, replacement of fish meal by the yeast culture improved the growth, immunity and disease resistance of channel catfish, and intestinal microbiota of channel catfish induced by the yeast culture played a critical role in these effects.


Assuntos
Doenças dos Peixes , Microbioma Gastrointestinal , Ictaluridae , Aeromonas hydrophila , Ração Animal/análise , Animais , Dieta/veterinária , Resistência à Doença , Ictaluridae/genética , Saccharomyces cerevisiae , Peixe-Zebra
12.
Fish Shellfish Immunol ; 125: 238-246, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35588906

RESUMO

NLRP1 (NLR family pyrin domain containing 1) is the first member of NOD-like receptors (NLRs) which can form inflammasome and play critical roles in innate immunity and pathogenesis of various diseases. To date, many NLRs and inflammasome-related genes have been identified in teleost, however, the activation of NLRP1 inflammasome is only found in zebrafish, and the activator of fish NLRP1 is unclear. In the present study, the activation of CcNLRP1 inflammasome and its function in innate immune defence of common carp was investigated. The expression of CcNLRP1 was induced in immune-related tissues of common carp upon challenge with Edwardsiella tarda and Aeromonas hydrophila. The colocalization of CcNLRP1 and CcASC, ASC oligomerization, and interaction between CcNLRP1CARD and CcASC was observed in 293T, Hela and EPC cells, suggesting that the CcNLRP1 inflammasome was activated in common carp. Furthermore, we found that MDP may be the specific ligand of CcNLRP1, which can activate the CcNLRP1 inflammasome. Taken together, the present study identifies a new inflammasome in common carp, and is beneficial to the control of infectious diseases in carp farming.


Assuntos
Carpas , Aeromonas hydrophila/fisiologia , Animais , Antibacterianos , Carpas/genética , Carpas/metabolismo , Proteínas de Peixes , Imunidade Inata/genética , Inflamassomos , Ligantes , Proteínas NLR/genética , Peixe-Zebra/metabolismo
13.
J Proteomics ; 264: 104621, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35618212

RESUMO

Aeromonas hydrophila is a widespread opportunistic pathogen of aquatic fishes in freshwater habitats. The current emergence of antimicrobial-resistant A. hydrophila has been reported in the world while the bacterial antibiotics adaptive mechanism remains poorly explored. In this study, using quantitative proteomics technology, the behavior of A. hydrophila was investigated by comparing the differentially expression proteins between with and without kanamycin (KAN) treatment. A total of 374 altered proteins including 184 increasing and 190 proteins decreasing abundances were quantified when responding to KAN stress. The bioinformatics analysis showed that stress related proteins were hub proteins that significantly increased to reduce the pressure from the misreading of mRNA caused by KAN. Moreover, several metallic pathways, such as oxidative phosphorylation and TCA cycle pathways may affect KAN resistance. Finally, eight selected genes were deleted and their antibiotics susceptibilities to kanamycin were valued, respectively. Results showed that OmpA II family protein A0KI26, and two-component system protein AtoC may involve in the KAN resistance in this study. In general, our results provide an insight into the behaviors of bacterial responding to KAN stress, and demonstrate the intrinsic antibiotics adaptive mechanism of A. hydrophila. BIOLOGICAL SIGNIFICANCE: In this study, the differentially expressed proteins (DEPs) of A. hydrophila strain between with and without kanamycin (KAN) were compared by using a data-independent acquisition (DIA) - based quantitative proteomics method. Bioinformatics analysis showed that stress - related proteins are hub proteins that significantly increased under KAN stress. Moreover, several metallic pathways, such as oxidative phosphorylation and citrate cycle (TCA cycle) pathways, can affect KAN resistance. Finally, our antibiotics susceptibility assay showed that the protein A0KI26 of the OmpA II family, and the AtoC of the two-component system may involve in KAN resistance in this study. These results provide insights into the antibiotics adaptation mechanism of A. hydrophila when responding to KAN stress.


Assuntos
Aeromonas hydrophila , Infecções por Bactérias Gram-Negativas , Aeromonas hydrophila/genética , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Humanos , Canamicina/farmacologia , Proteômica/métodos
14.
Fish Shellfish Immunol ; 126: 47-56, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35568142

RESUMO

CD209 is a type II transmembrane protein in the C-type lectin family, which is involved in the regulation of innate and adaptive immune system. Although it has been widely studied in mammals, but little has been reported about fish CD209 genes. In the present study, Megalobrama amblycephala CD209 (MaCD209) gene was cloned and characterized, its expression patterns, evolutionary characteristics, agglutinative and bacteriostatic activities were analyzed. These results showed that the open reading frame (ORF) of MaCD209 gene was 795 bp, encoding 264 aa, and the calculated molecular weight of the encoded protein was 29.7 kDa. MaCD209 was predicted to contain 2 N-glycosylation sites, 1 functional domain (C-LECT-DC-SIGN-like) and 1 transmembrane domain. Multiple sequence alignment showed that the amino acid sequence of MaCD209 was highly homologous with that of partial fishes, especially the highly conserved C-LECT-DC-SIGN-like domain and functional sites of CD209. Phylogenetic analysis showed that the CD209 genes from M. amblycephala and other cypriniformes fishes were clustered into one group, which was reliable and could be used for evolutionary analysis. Then, adaptive evolutionary analysis of teleost CD209 was conducted, and several positively selected sites were identified using site and branch-site models. Quantitative real-time PCR analysis showed that MaCD209 gene was highly expressed in the liver and heart. Moreover, the expression of MaCD209 was significantly induced upon Aeromonas hydrophila infection, with the peak levels at 4 h or 12 h post infection. The immunohistochemical analysis also revealed increased distribution of MaCD209 protein post bacterial infection. In addition, recombinant MaCD209 (rMaCD209) protein was prepared using a pET32a expression system, which showed excellent bacterial binding and agglutinative activities in a Ca2+-independent manner. However, rMaCD209 could only inhibit the proliferation of Escherichia coli rather than A. hydrophila. In conclusion, this study identified the MaCD209 gene, detected its expression and evolutionary characteristics, and evaluated the biological activities of rMaCD209 protein, which would provide a theoretical basis for understanding the evolution and functions of fish CD209 genes.


Assuntos
Cyprinidae , Cipriniformes , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Aeromonas hydrophila/fisiologia , Animais , Sequência de Bases , Clonagem Molecular , Cipriniformes/genética , Proteínas de Peixes/química , Mamíferos/genética , Mamíferos/metabolismo , Filogenia , Proteínas Recombinantes/genética
15.
Fish Shellfish Immunol ; 126: 197-210, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35609760

RESUMO

Ferritin M is involved in the regulation of fish immunity. In this study, open reading frame (ORF) sequences of ferritin M from hybrid fish and its parental species were 534 bp. Tissue-specific analysis indicated that the highest level of ferritin M from red crucian carp was observed in kidney, while peaked expressions of ferritin M from white crucian carp and hybrid carp were observed in gill. Elevated levels of ferritin M from hybrid carp and its parental species were detected in immune-related tissues following Aeromonas hydrophila infection or in cultured fish cell lines after lipopolysaccharide (LPS) challenge. Ferritin M overexpression could attenuate NF-κB and TNFα promoter activity in their respective fish cells. Purified ferritin M fusion proteins elicited in vitro binding activity to A. hydrophila and Edwardsiella tarda, lowered bacterial dissemination to tissues and alleviated inflammatory response. Furthermore, treatment with ferritin M fusion proteins could mitigate bacteria-induced liver damage and rescue antioxidant activity. These results suggested that ferritin M in hybrid fish showed a similar immune defense against bacteria infection in comparison with those of its parental species.


Assuntos
Infecções Bacterianas , Carpas , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Aeromonas hydrophila/fisiologia , Animais , Carpas/metabolismo , Ferritinas , Proteínas de Peixes , Carpa Dourada
16.
Fish Shellfish Immunol ; 125: 258-265, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35580796

RESUMO

The purpose of this study was to investigate the effect of Bacillus amyloliquefaciens LSG2-8 on the growth performance, immune function, antioxidant capacity, and disease resistance of Rhynchocypris lagowskii. Fish were fed with the feed containing five levels such as 0, 1.0 × 106, 1.0 × 107, 1.0 × 108, and 1.0 × 109 CFU/g of the B. amyloliquefaciens LSG2-8 for 56 days. After 56 days of feeding, twenty four fish were randomly selected to test various growth, immune and antioxidant parameters. Ten fish were challenged with Aeromonas hydrophila for 14 days; the mortality rate was recorded 14 days after infection. The results showed that B. amyloliquefaciens LSG2-8 could significantly increase the growth parameters of R. lagowskii's, such as final body weight, weight gain rate, specific growth rate, and feed efficiency (p < 0.05). Further examination revealed the activity of antioxidant enzymes, Nrf-2 mRNA, and Keap-1 mRNA gene expression in the intestine and liver, and the serum immune index of R. lagowskii in the 1.0 × 108 CFU/g were all significantly higher compared to the other groups. Furthermore, fish fed a diet supplemented with B. amyloliquefaciens LSG2-8 had a significantly lower (p < 0.05) post-challenge mortality rate than the control fish. In summary, the research results showed that B. amyloliquefaciens LSG2-8 could improve the growth performance, immune function, antioxidant capacity, and disease resistance of R. lagowskii and be used in aquaculture.


Assuntos
Bacillus amyloliquefaciens , Cipriniformes , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Probióticos , Aeromonas hydrophila , Ração Animal/análise , Animais , Antioxidantes/metabolismo , Dieta/veterinária , Resistência à Doença , Probióticos/farmacologia , RNA Mensageiro
17.
Curr Med Res Opin ; 38(7): 1125-1132, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35575163

RESUMO

INTRODUCTION: Aeromonads are gram-negative opportunistic bacteria, mainly found in aquatic environments. Hematologic patients are particularly at risk of Aeromonas soft tissue infections and septicemia, especially during chemotherapy-induced neutropenia. CASE DESCRIPTION: A 46-year-old man was diagnosed with acute lymphoblastic leukemia characterized by the rare t(12;17)(p13;q21)/TAF15-ZNF384 aberration. On day 22 of chemotherapy, he developed febrile neutropenia followed by necrotizing fasciitis in his upper right extremity. Despite appropriate antibiotic therapy and prompt surgical intervention, he died within 36 h after the appearance of a fever. A multi-sensitive Aeromonas hydrophila was isolated from all cultural sites. DISCUSSION AND CONCLUSIONS: In a previous paper we characterized the patient's aberration with cytogenetic and FISH analysis. Here, we provide details regarding the patient's rapidly progressing infection and underline the importance of maintaining high clinical suspicion of Aeromonas infections in acute leukemia. Given the unusually rapid progression of an infection caused by a rare non-resistant pathogen, and after considering data on the implication of metalloproteinase function in immune system regulation, a correlation between risk of severe infection and TAF15-ZNF384 aberrated acute lymphoblastic leukemia cannot be ruled out.


Assuntos
Infecções por Bactérias Gram-Negativas , Leucemia Mieloide Aguda , Leucemia-Linfoma Linfoblástico de Células Precursoras , Infecções dos Tecidos Moles , Doença Aguda , Aeromonas hydrophila , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Humanos , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Infecções dos Tecidos Moles/complicações , Translocação Genética
18.
Int Microbiol ; 25(3): 605-613, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35438439

RESUMO

Aeromonas hydrophila is a common pathogen in fish that has caused severe economic losses in aquaculture worldwide. With the emergence of bacterial resistance, it is necessary to develop new drugs to combat bacterial infection, particularly for multidrug-resistant bacteria. In this study, the antibacterial activity of pinocembrin was investigated by observing bacterial growth and microscopic structure, and its mechanism of action was identified by investigating its effect on protein and DNA. The antibacterial susceptibility test indicated that pinocembrin inhibits A. hydrophila growth. The minimal inhibitory concentration and minimum bactericidal concentration were 256 µg/mL and 512 µg/mL, respectively. Ultrastructurally, the bacteria treated with pinocembrin showed surface roughness and plasmolysis. When bacteria were treated with 512 µg/mL pinocembrin, lactate dehydrogenase activity and soluble protein content decreased significantly, and electrical conductivity and DNA exosmosis levels increased by 4.21 ± 0.64% and 15.98 ± 1.93 mg/L, respectively. Staining with 4', 6-Diamidino-2-phenylindole showed that the nucleic acid fluorescence intensity and density decreased after the treatment with pinocembrin. Pinocembrin may inhibit the growth of A. hydrophila by increasing cell membrane permeability and affecting protein and DNA metabolism. Thus, pinocembrin is a candidate drug for the treatment of A. hydrophila infection in aquaculture.


Assuntos
Doenças dos Peixes , Flavanonas , Aeromonas hydrophila , Animais , Antibacterianos/química , Doenças dos Peixes/tratamento farmacológico , Doenças dos Peixes/microbiologia , Flavanonas/farmacologia , Flavanonas/uso terapêutico , Testes de Sensibilidade Microbiana
19.
Fish Shellfish Immunol ; 124: 525-533, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35489592

RESUMO

The present study was performed to determine the effects of Aeromonas hydrophila infection on intestinal -histopathology, innate immune response and changes in antioxidant capacity of blunt snout bream (Megalobrama amblycephala). A series of histopathological changes, innate immune enzyme activities, antioxidant enzyme activities, and the corresponding mRNA relative genes expressions in intestines were measured at 0, 1, 2, and 3 weeks post-treatment of Aeromonas hydrophila (1✕107 CFU mL-1) infection. The results showed that Aeromonas hydrophila induced changes in intestinal morphology, including the decreased muscularis thickness, the proliferated goblet cells, and the atrophied intestine villi height. Moreover, the innate immune enzymes activities in serum such as acid phosphatase, alkaline phosphatase, lysozyme activities and immunoglobulin M were significantly reduced after infection at 1week, 2week and 3week. The contents of complement 3 and complement 4 were significantly decreased after infection as well. In addition, the antioxidant enzymes activities, including superoxide dismutase, catalase and glutathione peroxidase in the experimental groups were significantly decreased compared with the control group, whereas the content of malondialdehyde was significantly increased after infection at 1week, 2week and 3week. Furthermore, the mRNA relative expressions of the inflammatory cytokines such as tumor necrosis factor-α, interleukins-1ß, interferon-γ, and interleukins-6 were significantly increased after infection with Aeromonas hydrophila. The TJ-related gene expressions in the intestine of zonula occluden-1, occludin, occludin-1, occludin-2 were significantly reduced throughout the infection period. The mRNA relative expressions of signal transducers and activators of transcription 4 and janus kinase-3 in the intestine were significantly ascended compared with the non-infected group. Overall, the results elucidated that the intestine tissue injury and innate immune response reduction, as well as antioxidant capacity attenuation were occurred against Aeromonas hydrophila infection of the blunt snout bream.


Assuntos
Cyprinidae , Cipriniformes , Infecções por Bactérias Gram-Negativas , Aeromonas hydrophila/fisiologia , Animais , Antioxidantes/metabolismo , Cyprinidae/genética , Cipriniformes/genética , Suplementos Nutricionais , Proteínas de Peixes/metabolismo , Imunidade Inata , Interleucinas/metabolismo , Intestinos , Ocludina/metabolismo , Ocludina/farmacologia , RNA Mensageiro/metabolismo
20.
Fish Shellfish Immunol ; 124: 1-11, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35378306

RESUMO

Ladderlectin is a pattern recognition receptor (PRR) in fish that is critical for rapid detection of bacteria in vitro, but the immunological function of ladderlectin in vivo is essentially unknown. In this study, we examined the expression and function of a ladderlectin homologue (WR-ladderlectin) from hybrid crucian carp. WR-ladderlectin contains 157 amino acids and possesses the conserved C-type lectin domain. WR-ladderlectin is mainly expressed in the intestine and is upregulated by bacterial infection. Recombinant WR-ladderlectin (rWR-ladderlectin) agglutinated Aeromonas hydrophila and Escherichia coli. rWR-ladderlectin also bound the A. hydrophila and E. coli in a protein dose-dependent manner. As well as its ability to bind bacterial cells, rWR-ladderlectin displayed apparent bactericidal activity against A. hydrophila and E. coli in vitro. When introduced in vivo, rWR-ladderlectin induced significant expression of the antimicrobial molecules and tight junctions in the intestine. In addition, rWR-ladderlectin prevented significant decrease in the length of intestine villus and enhanced the host's resistance to bacterial infection. These results indicate that WR-ladderlectin is a classic pattern recognition molecule that protects intestinal mucosal barrier against bacterial infection.


Assuntos
Infecções Bacterianas , Carpas , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Aeromonas hydrophila/fisiologia , Animais , Carpas/metabolismo , Escherichia coli , Proteínas de Peixes , Imunidade Inata
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...