{"title":"Preliminary study on ameliorative effects of P-Hydroxycinnamic acid on high-fat diet-induced injury in zebrafish.","authors":"Qianyao Kuang, Delong Meng, Zhen Zhang, Xingyu Chen, Tsegay Teame, Hongwei Yang, Yalin Yang, Chao Ran, Yuanyou Li, Zhigang Zhou","doi":"10.1016/j.fsi.2025.110457","DOIUrl":"https://doi.org/10.1016/j.fsi.2025.110457","url":null,"abstract":"<p><p>P-Hydroxycinnamic acid (PCA), a natural phenolic compound, exhibits multifaceted biological activities, including antioxidant and metabolic regulatory properties in mammals, whereas its role in fish is rarely reported. To investigate whether PCA can alleviate the negative effects caused by high-fat diets on fish liver health and disease resistance, here we used zebrafish as experimental animals. In this study, six zebrafish diets, including basal diet, high-fat diet (HFD), and HFD supplemented with PCA at 500, 1000, 1500, or 2500 mg/kg and assigned as CK, HFD, PCA0.5, PCA1, PCA1.5, and PCA2.5, respectively. Following a 6-week feeding trial on zebrafish, PCA supplementation significantly attenuated hepatic triglyceride (TAG) accumulation without compromising growth performance. With increasing the level of PCA, the expression of inflammatory factors showed an upregulating trend. Serum biomarkers of liver injury (ALT, AST) were markedly reduced in PCA-treated groups, concomitant with enhanced hepatic antioxidant capacity (CAT, GR) and upregulated the expression of anti-inflammatory cytokines (tgf-β). Notably, PCA administration improved survival rates following a dual challenge with Aeromonas veronii HM091 and Aeromonas hydrophila NJ-1. These findings demonstrate that PCA0.5 supplementation effectively mitigates HFD-induced oxidative stress and hepatic steatosis while enhancing innate immunity in zebrafish.</p>","PeriodicalId":12127,"journal":{"name":"Fish & shellfish immunology","volume":" ","pages":"110457"},"PeriodicalIF":4.1,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144181534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Crisleri Carrera , Milton F. Villegas , Carolina Muñoz-Flores , Leonardo Ortega , Santiago Salazar , Ariel Valenzuela , Niza Agurto , Raquel Montesino , Alex Romero , Bastian Couso , Jorge Saavedra , Rafael Maura , Natalie Parra , Fátima Reyes , Alfredo Saavedra , Oliberto Sánchez , Jorge R. Toledo , Jannel Acosta
{"title":"Evaluating the adjuvant potential of NK-lysin and HMGB1-derived peptides in enhancing immune responses in Salmo salar","authors":"Crisleri Carrera , Milton F. Villegas , Carolina Muñoz-Flores , Leonardo Ortega , Santiago Salazar , Ariel Valenzuela , Niza Agurto , Raquel Montesino , Alex Romero , Bastian Couso , Jorge Saavedra , Rafael Maura , Natalie Parra , Fátima Reyes , Alfredo Saavedra , Oliberto Sánchez , Jorge R. Toledo , Jannel Acosta","doi":"10.1016/j.fsi.2025.110462","DOIUrl":"10.1016/j.fsi.2025.110462","url":null,"abstract":"<div><div>The development of effective vaccines for aquaculture is crucial to prevent infectious diseases and improve fish health. Inactivated and subunit vaccines are commonly used in salmon farming; however, their immunogenicity is often limited, requiring adjuvants to enhance their efficacy. In this study, we evaluated the adjuvant potential of immunomodulatory peptides derived from HMGB1 (11W) and NK-lysin (NK1 and NK4) in formulations containing the VP2 antigen of infectious pancreatic necrosis virus (IPNv) in <em>Salmo salar</em>. The peptides were co-administered with the recombinant VP2 protein by intraperitoneal injection in different experimental groups, and serum samples were subsequently analyzed to determine IgM levels. Furthermore, the induction of the cytokines IFN-γ, IL-17, and IL-4/13A in tissues and leukocytes from head kidneys re-stimulated with the antigen was evaluated by RT-qPCR. The results indicated that the formulations containing NK1, NK4, and 11W progressively stimulated IgM production from day 35 post-vaccination. Furthermore, these adjuvant peptides significantly induced the expression of the evaluated cytokines in the head kidney and spleen of immunized animals and in the primary culture model, suggesting the activation of Th1, Th2, and Th17 responses. These findings suggest that peptide adjuvants can enhance the immune response in salmonid vaccination, offering a promising alternative to conventional adjuvants.</div></div>","PeriodicalId":12127,"journal":{"name":"Fish & shellfish immunology","volume":"164 ","pages":"Article 110462"},"PeriodicalIF":4.1,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144169124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effect of exchange of viral hemorrhagic septicemia virus (VHSV) G protein's signal peptide with piscidin signal peptide on virus replication and immunogenicity","authors":"Mariem Bessaid, Ki Hong Kim","doi":"10.1016/j.fsi.2025.110455","DOIUrl":"10.1016/j.fsi.2025.110455","url":null,"abstract":"<div><div>Signal peptides (SPs) play a critical role in the targeting and secretion of viral glycoproteins, influencing both replication efficiency and immunogenicity. In this study, we investigated the effects of replacing the native signal peptide of the viral hemorrhagic septicemia virus (VHSV) glycoprotein (vG) with a heterologous piscidin-derived signal peptide (Psp). Using a luciferase reporter assay, we demonstrated that Psp significantly enhanced secretory efficiency compared to the native VHSV SP. A recombinant VHSV expressing Psp-fused glycoprotein (rVHSV-PspvG) was generated via reverse genetics to evaluate the impact of SP substitution on viral replication and immunogenicity. While rVHSV-PspvG was successfully rescued and retained infectivity, it exhibited slower replication kinetics and smaller plaque formation relative to the wild-type recombinant virus (rVHSV-wild). Enhanced Thioflavin T fluorescence in EPC cells infected with rVHSV-PspvG suggested increased ER stress associated with Psp substitution, likely contributing to reduced viral assembly. <em>In vivo</em> virulence assays in olive flounder (<em>Paralichthys olivaceus</em>) revealed attenuated pathogenicity of rVHSV-PspvG, which correlated with lower viral loads in head kidney tissues. Furthermore, a DNA vaccine encoding the PspvG construct conferred partial protection (60 % survival) upon VHSV challenge, whereas the native vG-based vaccine provided complete protection. These findings highlight the dual impact of SP modification on viral replication and host immunity, underscoring the need for cautious SP engineering in the development of live attenuated viruses and DNA vaccines.</div></div>","PeriodicalId":12127,"journal":{"name":"Fish & shellfish immunology","volume":"164 ","pages":"Article 110455"},"PeriodicalIF":4.1,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144155192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Evaluation of immune-related parameters in acellular and cellular fractions in male and female of Atlantic blue crabs (Callinectes sapidus)","authors":"Ricardo Gálvez, Francisco A. Guardiola","doi":"10.1016/j.fsi.2025.110456","DOIUrl":"10.1016/j.fsi.2025.110456","url":null,"abstract":"<div><div>Brachyurans are relatively understudied compared to other decapods, with numerous fields remaining to be explored, including the immune response. Therefore, the aim of this study was to characterize several immune-related enzymes and activities of the Atlantic blue crab (<em>Callinectes sapidus</em>) in cell-free haemolymph (CFH) and in the haemocyte lysate supernatant (HLS), considering the gender factor and the suitability of measuring each activity in CFH or HLS. Data were expressed by millilitres of haemolymph or milligrams of protein to identify which of these units would be more robust and informative. For this, haemolymph of each gender was collected, and centrifuged to obtain CFH samples, whilst the cells were sonicated to get the HLS. Our results revealed that the protein concentration was higher in CFH compared to HLS. Considering milligrams of protein as units, phenoloxidase and esterase activities were lower in CFH regarding to HLS in both genders. Similarly, the lysozyme and phosphatase activities were lower in CFH compared to HLS but only in females. The values of lysozyme activity were higher in HLS of females compared to males. Studying millilitre of haemolymph as units, lysozyme activity exhibited higher activity in CFH compared to HLS in both genders, whilst phenoloxidase and esterase activities were higher in HLS, showing variations only in males. Interestingly, alkaline phosphatase activity was undetected in CFH male. Any variation was observed between the activities measured in both genders. Protease and antiprotease activities were higher and lower in CFH compared to HLS values, respectively, whilst any variation was observed between genders. Bactericidal activity against <em>V. harveyi</em>, <em>V. alginolyticus</em> and <em>V. anguillarum</em> exhibited stronger values in HLS than in CFH, independently of gender, as well as against <em>P. damselae</em> in females. Considering gender factor, the bactericidal activity against <em>V. alginolyticus</em>, <em>V. anguillarum</em> and <em>P. damselae</em> was higher in HLS of females than in males. However, the bactericidal activity against <em>V. alginolyticus</em> and <em>P. damselae</em> was higher in CFH of males compared to females. Our results could contribute to gender selection in future brachyurans studies considering the variability between males and females due to their distinct biology. Additionally, we provide data regarding the baseline values of several immune-related activities, establishing the most appropriate units from the biological point of view.</div></div>","PeriodicalId":12127,"journal":{"name":"Fish & shellfish immunology","volume":"164 ","pages":"Article 110456"},"PeriodicalIF":4.1,"publicationDate":"2025-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144155193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhihao Ju , Qianqian Xiang , Tiyuan Xia , Keira Harshaw , Neil Rooney , Jinmei Zi , Zijin Hong , Xuexiu Chang
{"title":"Microcystis aeruginosa decreased fish appetite via inducing intestinal inflammation","authors":"Zhihao Ju , Qianqian Xiang , Tiyuan Xia , Keira Harshaw , Neil Rooney , Jinmei Zi , Zijin Hong , Xuexiu Chang","doi":"10.1016/j.fsi.2025.110428","DOIUrl":"10.1016/j.fsi.2025.110428","url":null,"abstract":"<div><div><em>Microcystis aeruginosa</em> is a dominant and widely distributed cyanobacterium that plays a major role in the formation and recurrence of harmful algal blooms in lakes. While it is known to cause intestinal inflammation and appetite dysregulation in fish, the relationship between these effects and their underlying molecular mechanisms remains poorly understood. This study explored the impact of <em>M. aeruginosa</em>-induced intestinal inflammation on fish appetite, with a focus on the underlying molecular pathways, using <em>Pseudorasbora parva</em> exposed to <em>M. aeruginosa</em> for 96 h. We found a significant increase in inflammatory cells in the intestinal tract, accompanied by notable changes in glycerophospholipid and tryptophan metabolism, pathways associated with inflammation and appetite regulation. Key inflammatory markers interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-1 beta (IL-1β), Nuclear factor-kappaB (NF-κB), and tumor necrosis factor-alpha (TNF-α) were significantly elevated, while orexigenic factors orexins, ghrelin, acetylcholine (Ach), and dopamine (DA) were markedly reduced. In contrast, anorexigenic factors 5-Hydroxytryptamine (5-HT), gamma-aminobutyric acid (GABA), proopiomelanocortin (POMC), and glucagon-like peptide-1 (GLP-1) showed significant increases. Correlation analysis revealed that inflammatory markers were negatively correlated with orexigenic factors and positively correlated with anorexigenic factors. These findings indicate that <em>M. aeruginosa</em>-induced intestinal inflammation is a potential mechanism underlying reduced appetite in fish. This study provides novel insights into the toxic effects of <em>M. aeruginosa</em> on fish and offers a new perspective on the mechanisms by which it suppresses fish appetite, contributing to the broader understanding of the ecological and physiological impacts of cyanobacterial blooms.</div></div>","PeriodicalId":12127,"journal":{"name":"Fish & shellfish immunology","volume":"164 ","pages":"Article 110428"},"PeriodicalIF":4.1,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144141906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xin Zhang, Yan Ling Sun, Qiang Fu, Chao Li, Hui Jun Huo
{"title":"Establishment of a gill-derived cell line in Sebastes schlegelii with practicability in studies of bacterial pathogen-host interaction","authors":"Xin Zhang, Yan Ling Sun, Qiang Fu, Chao Li, Hui Jun Huo","doi":"10.1016/j.fsi.2025.110454","DOIUrl":"10.1016/j.fsi.2025.110454","url":null,"abstract":"<div><div>In this study, we established and described a continuous cell line derived from gill of <em>Sebastes schlegelii</em>, named SSG. This cell line has been successively cultured for over 50 passages. Karyotype analysis confirmed the presence of 48 normal diploid chromosomes in the cells. Sequencing results of <em>COX1</em> and <em>16S rRNA</em> genes verified the <em>S. schlegelii</em> origin of SSG cells. SSG demonstrated moderate transfection efficiency with siRNA probes, indicating its potential for gene interference studies. Infection sensitivity assessments revealed that <em>Edwardsiella piscicida</em> can successfully survive and proliferate in SSG, triggering an immune response characterized by the substantial production of reactive oxygen species (ROS) and the upregulation of immune-related genes. This <em>in vitro</em> infection model provides an effective tool for studying bacterial pathogen-host interaction mechanisms in gill of <em>S. schlegelii</em> and holds significant importance for the prevention and control of bacterial diseases in this species.</div></div>","PeriodicalId":12127,"journal":{"name":"Fish & shellfish immunology","volume":"165 ","pages":"Article 110454"},"PeriodicalIF":4.1,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144141903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Recombinant snakehead rhabdovirus-mediated expression of white spot syndrome virus (WSSV) VP28 confers protection against WSSV in Penaeus vannamei","authors":"Myoung Gwang Choi, Soon Joo Hong, Ki Hong Kim","doi":"10.1016/j.fsi.2025.110439","DOIUrl":"10.1016/j.fsi.2025.110439","url":null,"abstract":"<div><div>White spot syndrome virus (WSSV) is a major pathogen responsible for significant economic losses in global shrimp aquaculture. In this study, we developed a recombinant snakehead rhabdovirus (rSHRV) expressing the WSSV VP28 envelope protein (designated rSHRV-AVP28) and evaluated its potential as a vaccine candidate for <em>Penaeus vannamei</em>. The VP28 gene was successfully inserted between the N and P genes of the SHRV genome, and the rescued virus demonstrated plaque formation and intracellular VP28 expression, although the antigen was not incorporated into viral particles. Vaccination with rSHRV-AVP28 significantly reduced cumulative mortality to ∼30 % upon WSSV challenge, compared to 100 % mortality in both buffer- and vector-control groups. Quantitative PCR revealed a 10,000-fold reduction in WSSV viral load in the rSHRV-AVP28 group, with surviving shrimp exhibiting viral titers below 10<sup>4</sup> copies/mg of muscle tissue. These results demonstrate that rSHRV-AVP28 effectively induces protective immunity in shrimp, highlighting the potential of rhabdovirus-based vectors as novel delivery platforms for crustacean vaccines.</div></div>","PeriodicalId":12127,"journal":{"name":"Fish & shellfish immunology","volume":"164 ","pages":"Article 110439"},"PeriodicalIF":4.1,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144138904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Zebrafish CD44a variants suppress antiviral immunity through regulation of RIG-I ubiquitination and degradation","authors":"Lu Cao , Ming Xian Chang","doi":"10.1016/j.fsi.2025.110442","DOIUrl":"10.1016/j.fsi.2025.110442","url":null,"abstract":"<div><div>Viral infections represent a major threat to host survival, with type I interferon (IFN-I) signaling serving as a central antiviral defense mechanism. The RIG-I-like receptor RIG-I detects viral RNA to initiate IFN-I production, yet the post-translational mechanisms regulating its activity remain poorly understood in teleost. While zebrafish CD44a, a cell adhesion molecule, protects against bacterial infections, its role in viral immunity—specifically in modulating RIG-I-mediated IFN-I signaling—has not yet been elucidated. This study characterizes the functions of zebrafish CD44a splice variants (CD44a_tv1 and CD44a_tv2) during Spring viremia of carp virus (SVCV) infection. Ectopic expression of CD44a variants enhanced viral replication and larval mortality, whereas CD44a deficiency reduced viral load and improved survival. Mechanistically, CD44a variants promoted K48-linked polyubiquitination and proteasomal degradation of RIG-I while inhibiting K63-linked activation-related ubiquitination, disrupting RLR pathway activation. Direct physical interaction between CD44a variants and RIG-I was confirmed via co-immunoprecipitation and confocal microscopy, demonstrating CD44a variants directly bind to RIG-I to facilitate RIG-I degradation and suppress IFN-I responses. These findings reveal a novel role for CD44a in antiviral immunity through dual regulation of RIG-I ubiquitination, highlighting its context-dependent duality—protecting against bacteria but exacerbating viral pathogenesis. Inhibiting the pro-viral pathogenic activity of CD44a while preserving or augmenting its anti-bacterial protective function thereby establishes promising strategies for targeted therapies against pathogen-specific infectious diseases.</div></div>","PeriodicalId":12127,"journal":{"name":"Fish & shellfish immunology","volume":"164 ","pages":"Article 110442"},"PeriodicalIF":4.1,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144138903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Saco , M. Rey-Campos , A. Panebianco , B. Novoa , A. Figueras
{"title":"Comparative transcriptomics reveals different grades of susceptibility to a bacterial infection in bivalves","authors":"A. Saco , M. Rey-Campos , A. Panebianco , B. Novoa , A. Figueras","doi":"10.1016/j.fsi.2025.110443","DOIUrl":"10.1016/j.fsi.2025.110443","url":null,"abstract":"<div><div>Because of their filtering activity, bivalve species are constantly exposed to the wide presence of pathogenic microorganisms in seawater. In this work, the transcriptomic response after a waterborne bacterial infection with <em>Vibrio splendidus</em> was analyzed in hemolymph hemocytes from three bivalve species present in the same environment in Galicia: mussels (<em>Mytilus galloprovincialis</em>), cockles (<em>Cerastoderma edule</em>) and clams (<em>Ruditapes decussatus</em>). A clear transcriptomic immune modulation was observed in mussels and cockles, with shared responses such as immune recognition, inflammation, and oxidative stress. However, there were apparent differences, such as retrotransposons' regulation and apoptosis inhibition, exclusive to mussels. On the contrary, clams had very few modulated genes and almost no response to the infection. Metatranscriptomics showed each species' bacterial microbiome signature and a very high prevalence of <em>Vibrio</em> in the non-responsive clam individuals. These <em>Vibrio</em> reads were retrieved and used for a dual transcriptomics approach that revealed modulated bacterial genes related to their virulence in the clam samples, indicating that the bacteria could be in control of this interaction. This work showed that there are clear differences between the innate immune systems of different bivalves to the same infection and could indicate a greater vulnerability of the clam to certain bacterial pathogens.</div></div>","PeriodicalId":12127,"journal":{"name":"Fish & shellfish immunology","volume":"165 ","pages":"Article 110443"},"PeriodicalIF":4.1,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144141886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}