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Animals : An Open Access Journal From... Oct 2023R-(+)-limonene is a monoterpene from plants of the genus with diverse biological properties. This research evaluated the effects of dietary supplementation with...
R-(+)-limonene is a monoterpene from plants of the genus with diverse biological properties. This research evaluated the effects of dietary supplementation with R-(+)-limonene on growth, metabolic parameters in plasma and liver, and the antioxidant and stress responses in silver catfish, , challenged or not with . Fish were fed for 67 days with different doses of R-(+)-limonene in the diet (control 0.0, L0.5, L1.0, and L2.0 mL/kg of diet). On the 60th day, a challenge with was performed. R-(+)-limonene in the diet potentiated the productive performance of the fish. The metabolic and antioxidant responses indicate that R-(+)-limonene did not harm the health of the animals and made them more resistant to the bacterial challenge. Histological findings showed the hepatoprotective effect of dietary R-(+)-limonene against . mRNA levels were upregulated in the liver of fish fed with an L2.0 diet but downregulated with bacterial challenge. The expression levels of mRNA were higher in the brains of fish fed with the L2.0 diet. However, the L2.0 diet downregulated and mRNA expression in the brains of infected fish. In conclusion, the results indicated that R-(+)-limonene can be considered a good dietary supplement for silver catfish.
PubMed: 37958062
DOI: 10.3390/ani13213307 -
Plants (Basel, Switzerland) Oct 2023This research comparatively investigates the in vitro antimicrobial activity of extracts from (pink water lily) leaves against pathogenic bacteria. The experimental...
This research comparatively investigates the in vitro antimicrobial activity of extracts from (pink water lily) leaves against pathogenic bacteria. The experimental extracts are aqueous, acetonic, and 95% ethanolic extracts; and the pathogenic bacteria being studied include , , , and , which are commonly found in freshwater fish and brackish aquatic animals. The ethanolic extract achieves the highest bacterial inhibitory effects against and . The minimum inhibitory concentrations of the ethanolic extract against and are 10 mg/mL; and 2.5 mg/mL against and . The ethanolic extract is effective against . The high-performance liquid chromatography results show that, in the phenolic acids group, gallic acid is the most dominant (0.600-3.21% /), followed by sinapic acid (0.37-0.83% /). In the flavonoids group, catechin is the most dominant (0.02-1.08% /), followed by rutin (0.002-0.03% /). Essentially, the ethanolic extract can potentially be used as a natural antibiotic agent to treat bacterial infections in fish and aquatic animals.
PubMed: 37896051
DOI: 10.3390/plants12203588 -
Biomedicines Aug 2023Green synthesis of metallic nanoparticles is an auspicious method of preparing nanoparticles using plant extracts that have lesser toxicity to animal cells and the host....
Green synthesis of metallic nanoparticles is an auspicious method of preparing nanoparticles using plant extracts that have lesser toxicity to animal cells and the host. In the present work, we analyzed the antibacterial activity of and -mediated silver nanoparticles (Cc-AgNPs and Pg-AgNPs, respectively) against () in an in vivo assay employing (). were divided into six groups for both Cc-AgNPs and Pg-AgNPs treatments separately: Control, infected, + Ampicillin, + Cc/Pg-AgNPs (25 µg/L), + Cc/Pg-AgNPs (50 µg/L), and + Cc/Pg-AgNPs (75 µg/L). Changes in different bio-indicators such as hematological, histological, oxidative stress, and cytokine analysis were observed. Interestingly, the infected fish treated with both types of AgNPs (Cc-AgNPs and Pg-AgNPs) exhibited a higher survival rate than the untreated infected fish and demonstrated signs of recovery from the infection, providing a compelling indication of the positive impact of phytosynthesized AgNPs. Disruptions in hematological and histological parameters were found in the infected fish. Both Cc-AgNPs and Pg-AgNPs showed recovery on the hematological and histological parameters. Analysis of oxidative stress and cytokine markers also revealed provoking evidence of the positive impact of Cc-AgNPs and Pg-AgNPs treatment against disease progression in the infected fish. The major finding of the study was that the higher concentrations of the nanoparticles (50 µg/L in the case of Cc-AgNPs and 75 µg/L in the case of Pg-AgNPs) were more effective in fighting against disease. In conclusion, our work presents novel insights for the use of green-synthesized AgNPs as economic and innocuous antibacterial candidates in aquaculture.
PubMed: 37760791
DOI: 10.3390/biomedicines11092349 -
Animals : An Open Access Journal From... Oct 2023This study examined the impact of dietary limonene treatment on the growth performance, immune response, and disease resistance of common carp, . The fish were fed with...
This study examined the impact of dietary limonene treatment on the growth performance, immune response, and disease resistance of common carp, . The fish were fed with either a control diet (CTL; no limonene supplementation) or four experimental diets containing 50 (50 L), 100 (100 L), 200 (200 L), and 400 (400 L) mg/kg limonene over a 70-day period, followed by challenge. The 200 L treatment resulted in a significant decrease in FCR compared to the CTL treatment. The highest post-challenge mortality was associated with the CTL treatment (62.7%), while the 200 L treatment had the lowest mortality (30.7%). Before the challenge, dietary limonene significantly increased humoral and skin mucosal immune parameters compared to the CTL treatment. The highest leukocyte, lymphocyte counts, skin mucosal protease activity, and intestinal lactic acid bacteria were observed in the 200 L treatment before the challenge. The highest plasma lysozyme activity was observed in the 400 L treatment, whereas the highest skin mucosal lysozyme and peroxidase activities were observed in the 100 L and 200 L treatments before the challenge. There were no significant differences in the blood neutrophil, monocyte, and eosinophil counts, humoral alternative complement activity, skin mucosal alkaline phosphatase activity, and the intestinal total viable bacteria among the treatments before the challenge. After the challenge, the 200 L treatment exhibited the highest leukocyte, neutrophil, and monocyte count, skin mucosal immune parameters, and intestinal lactic acid bacteria, whereas the highest blood eosinophil count was observed in the 100 L, 200 L, and 400 L treatments. At this time, the lowest blood lymphocyte counts were observed in the 100 L and 200 L, but the lowest intestinal total viable bacteria were observed in the 100 L, 200 L, and 400 L treatments. Based on these findings, dietary limonene at 200 mg/kg is ideal for common carp to promote feed efficiency, innate immunity boosting, and resistance against .
PubMed: 37893921
DOI: 10.3390/ani13203197 -
International Journal of Molecular... Jul 2023The vertebrate mucosal barrier comprises physical and immune elements, as well as bioactive molecules, that protect organisms from pathogens. Vitamin D is a vital...
The vertebrate mucosal barrier comprises physical and immune elements, as well as bioactive molecules, that protect organisms from pathogens. Vitamin D is a vital nutrient for animals and is involved in immune responses against invading pathogens. However, the effect of vitamin D on the mucosal barrier system of fish, particularly in the skin, remains unclear. Here, we elucidated the effect of vitamin D supplementation (15.2, 364.3, 782.5, 1167.9, 1573.8, and 1980.1 IU/kg) on the mucosal barrier system in the skin of grass carp () challenged with . Dietary vitamin D supplementation (1) alleviated -induced skin lesions and inhibited oxidative damage by reducing levels of reactive oxygen species, malondialdehyde, and protein carbonyl; (2) improved the activities and transcription levels of antioxidant-related parameters and nuclear factor erythroid 2-related factor 2 signaling; (3) attenuated cell apoptosis by decreasing the mRNA and protein levels of apoptosis factors involved death receptor and mitochondrial pathway processes related to p38 mitogen-activated protein kinase and c-Jun N-terminal kinase signaling; (4) improved tight junction protein expression by inhibiting myosin light-chain kinase signaling; and (5) enhanced immune barrier function by promoting antibacterial compound and immunoglobulin production, downregulating pro-inflammatory cytokine expression, and upregulating anti-inflammatory cytokines expression, which was correlated with nuclear factor kappa B and the target of rapamycin signaling pathways. Vitamin D intervention for mucosal barrier via multiple signaling correlated with vitamin D receptor a. Overall, these results indicate that vitamin D supplementation enhanced the skin mucosal barrier system against pathogen infection, improving the physical and immune barriers in fish. This finding highlights the viability of vitamin D in supporting sustainable aquaculture.
Topics: Animals; Diet; Aeromonas hydrophila; Immunity, Innate; Vitamin D; Fish Proteins; Gram-Negative Bacterial Infections; Vitamins; Carps; Animal Feed; Fish Diseases; Dietary Supplements
PubMed: 37511003
DOI: 10.3390/ijms241411243 -
Antioxidants (Basel, Switzerland) Dec 2023Fish possess numerous enzymatic antioxidant systems as part of their innate immunity. These systems have been poorly studied in (rohu). The present study characterized...
Antioxidant Defence in to Biotic and Abiotic Stress: Insight from mRNA Expression, Molecular Characterization and Recombinant Protein-Based ELISA of Catalase, Glutathione Peroxidase, CuZn Superoxide Dismutase, and Glutathione S-Transferase.
Fish possess numerous enzymatic antioxidant systems as part of their innate immunity. These systems have been poorly studied in (rohu). The present study characterized and investigated the role of antioxidant genes in the defence mechanisms against two types of stressors, including infection and ammonia stress. Four key genes associated with antioxidant activity-catalase, glutathione peroxidase, glutathione S-transferase, and CuZn superoxide dismutase were successfully cloned and sequenced. These genes were found to be expressed in different tissues and developmental stages of rohu. The expression levels of these antioxidant genes in the liver and anterior kidney tissues of rohu juveniles were modulated in response to bacterial infection (), parasite infection (), poly I:C stimulation and ammonia stress. Additionally, the recombinant proteins derived from these genes exhibited significant antioxidant and antibacterial activities. These proteins also demonstrated a protective effect against infection in rohu and had an immunomodulatory role. Furthermore, indirect ELISA assay systems were developed to measure these protein levels in healthy as well as and ammonia-induced rohu serum. Overall, this study characterized and emphasised the importance of the antioxidant mechanism in rohu's defence against oxidative damage and microbial diseases.
PubMed: 38275638
DOI: 10.3390/antiox13010018 -
Fish and Shellfish Immunology Reports Dec 2023Toll-like receptors (TLRs) play a crucial role in the recognition of microbial-associated molecular patterns in the innate immune system. Fish TLRs have undergone...
Toll-like receptors (TLRs) play a crucial role in the recognition of microbial-associated molecular patterns in the innate immune system. Fish TLRs have undergone significant gene expansion to adapt to complex aquatic environments. Among them, TLR20 from the TLR11 family actively responds to viral and bacterial invasions. Previous studies have reported two TLR20s in grass carp (), and in this study, we revised this conclusion. Based on the latest grass carp genome, we identified a new TLR20 member. These three TLR20s are arranged in tandem on chromosome 9, indicating that they are generated by gene duplication events. They were renamed CiTLR20.1 to CiTLR20.3 based on their chromosomal positions. The CiTLR20s in exhibit higher similarities with those in , and , and lower similarities with those in other distantly related fish species. Selective pressure analysis revealed low conservation and negative evolution of TLR20s during evolution. The 3D structures of the three TLR20s showed significant differences, reflecting functional variations and different downstream adaptor molecule recruitment. Transcriptome data revealed tissue distribution differences of TLR20s, with TLR20.1 showing relatively low expression levels in all the tissues, while TLR20.2 and TLR20.3 showed higher expression in the head kidney, spleen, and gill. Additionally, TLR20.2 and TLR20.3 actively responded to GCRV-II infection, with higher upregulation of TLR20.2 in response to challenge. In conclusion, this study corrected the number of grass carp TLR20 members and analyzed TLR20 from an evolutionary and structural perspective, exploring its role in antiviral and antibacterial defense. This study provides reference for future research on fish TLR20.
PubMed: 37841419
DOI: 10.1016/j.fsirep.2023.100119 -
Microorganisms Aug 2023Bacterial quorum sensing (QS) plays a crucial role in chemical communication between bacteria involving autoinducers and receptors and controls the production of...
Bacterial quorum sensing (QS) plays a crucial role in chemical communication between bacteria involving autoinducers and receptors and controls the production of virulence factors in bacteria. Therefore, reducing the concentration of signaling molecules in QS is an effective strategy for mitigating the virulence of pathogenic bacteria. In this study, we demonstrated that carvacrol at 15.625 μg/mL (1/4 MIC), a natural compound found in plants, exhibits potent inhibitory activity against QS in , as evidenced by a significant reduction (62.46%) in violacein production. Based on its impressive performance, carvacrol was employed as a natural QS inhibitor to suppress the pathogenicity of NJ-35. This study revealed a significant reduction (36.01%) in the concentration of N-acyl-homoserine lactones (AHLs), a QS signal molecular secreted by NJ-35, after 1/4 MIC carvacrol treatment. Moreover, carvacrol was found to down-regulate the expression of , two key genes in the QS system, which further inhibited the QS system of NJ-35. Finally, based on the above results and molecular docking, we proposed that carvacrol alleviate the pathogenicity of NJ-35 through QS inhibition. These results suggest that carvacrol could serve as a potential strategy for reducing the virulence of pathogenic bacteria and minimizing the reliance on antibiotics in aquaculture.
PubMed: 37630587
DOI: 10.3390/microorganisms11082027 -
Virus Research Jan 2024Aeromonas hydrophila is an opportunistic pathogen that frequently leads to significant mortality in various commercially cultured aquatic species. Bacteriophages offer...
Aeromonas hydrophila is an opportunistic pathogen that frequently leads to significant mortality in various commercially cultured aquatic species. Bacteriophages offer an alternative strategy for pathogens elimination. In this study, we isolated, identified, and characterized a novel temperate A. hydrophila phage, designated as P05B. The bacteriophage P05B is a myovirus based on its morphological features, and possesses the capability to lyse A. hydrophila strains isolated from shrimp. The optimal multiplicity of infection (MOI), adsorption rate, latent period, and burst size for phage P05B were determined to be 0.001, 91.7 %, 20 min, and 483 PFU/cell, respectively. Phage P05B displayed stability across a range of temperatures (28-50 °C) and pH values (4.0-10.0). Sequence analysis unveiled that the genome of phage P05B comprises 32,302 base pairs with an average G + C content of 59.4 %. A total of 40 open reading frames (ORF) were encoded within the phage P05B genome. The comparative genomic analyses clearly implied that P05B might represent a novel species of the genus Bielevirus under Peduoviridae family. A phylogenetic tree was reconstructed, demonstrating that P05B shares a close evolutionary relationship with other Aeromonas and Aeromonas phages. In conclusion, this study increased our knowledge about a new temperate phage of A. hydrophila with strong lytic ability.
Topics: Animals; Bacteriophages; Aeromonas hydrophila; Palaemonidae; Larva; Phylogeny; Ponds; Genome, Viral
PubMed: 37992971
DOI: 10.1016/j.virusres.2023.199279 -
Genes Oct 2023Hemoglobin (Hb) usually comprises two α and two β subunits, forming a tetramer responsible for oxygen transportation and storage. Few studies have elucidated fish...
Hemoglobin (Hb) usually comprises two α and two β subunits, forming a tetramer responsible for oxygen transportation and storage. Few studies have elucidated fish hemoglobin immune functions. is a freshwater-cultured fish prevalent in China. We identified two hemoglobin subunits and analyzed their expression patterns and antibacterial activities. The respective full-length cDNA sequences of the () and () subunits were 588 and 603 bp, encoding 143 and 148 amino acids. MaHbα and MaHbβ were highly homologous to hemoglobins from other fish, displaying typical globin-like domains, most heme-binding sites, and tetramer interface regions highly conserved in teleosts. In phylogenetic analyses, the hemoglobin genes from and other cypriniformes clustered into one branch, and those from other fishes and mammals clustered into other branches, revealing fish hemoglobin conservation. These subunits exhibit different expression patterns in various tissues and during development. is mainly expressed in the blood and brain, while gene expression is highest in the muscle. expression was detectable and abundant post-fertilization, with levels fluctuating during the developmental stages. expression began at 3 dph and gradually increased. Expression of both subunits was down-regulated in most examined tissues and time points post- infection, which might be due to red blood cell (RBC) and hematopoietic organ damage. Synthetic MaHbα and MaHbβ peptides showed excellent antimicrobial activities, which could inhibit survival and growth in five aquatic pathogens. Two hemoglobin subunits were identified, and their expression patterns and antibacterial activities were analyzed, thereby providing a basis for the understanding of evolution and functions of fish hemoglobins.
Topics: Animals; Cyprinidae; Phylogeny; Base Sequence; Amino Acid Sequence; Cypriniformes; Hemoglobins; Hemoglobin Subunits; Anti-Bacterial Agents; Mammals
PubMed: 37895322
DOI: 10.3390/genes14101972