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Frontiers in Physiology 2022The yellow catfish (), as one of the economically-relevant freshwater fish found in China, cannot tolerate cold stress. Understanding the physiological and biochemical...
The yellow catfish (), as one of the economically-relevant freshwater fish found in China, cannot tolerate cold stress. Understanding the physiological and biochemical mechanisms under cold stress may provide insights for improving yellow catfish management in the cold. Therefore, we investigated the metabolic and intestinal microbiota changes in cold stress in response to induced cold stress. We found that cold stress in yellow catfish lead to a significant increase in the consumption of glucose and triglycerides, as well as increased use of cholesterol as an alternate energy source. Moreover, cold stress also activated several significant biological processes in the fish such as thermogenesis, oxidative phosphorylation, the spliceosome machinery, RNA transport, protein processing that occurs in the ER, and purine and pyrimidine metabolism pathways involved in energy production. On the other hand, many other mechanisms like insulin resistance, starch and sucrose metabolism, and the glyoxylate and dicarboxylate metabolic pathways that also served as energy production pathways were weakened. Furthermore, organic acids and their derivatives as well as the lipids and lipid-like molecules were mainly altered in cold stress; prenol lipids, steroids, and their derivatives were significantly upregulated, while fatty acyls and glycerophospholipids were significantly downregulated. Transcriptomic and metabolomic integrated analysis data revealed that carbohydrate metabolism, lipid metabolism, amino acid metabolism, and nucleotide metabolism were involved in cold stress resistance. In addition, the intestinal microbiota abundance was also reduce and the pathogenic bacteria of plesiomonas was rapidly appreciation, which suggesting that cold stress also impaired intestinal health. This research study could offer insights into winter management or the development of feed to promote cold resistance in yellow catfish.
PubMed: 36176772
DOI: 10.3389/fphys.2022.985046 -
Frontiers in Microbiology 2022Teleost omnivorous fish that coexist partially sharing resources are likely to modify their gut traits and microbiome as a feedback mechanism between ecological...
Teleost omnivorous fish that coexist partially sharing resources are likely to modify their gut traits and microbiome as a feedback mechanism between ecological processes and evolution. However, we do not understand how the core gut microbiome supports the metabolic capacity of the host and regulates digestive functions in specialized omnivorous fish gut traits. Therefore, we evaluated the gut microbiome of eight omnivorous fish from a single family (i.e., Cyprinidae) in the current study. We examined the correlation between host phylogeny, diet composition, and intestinal morphological traits related to the intestinal microbiome. The results indicated that cyprinid fish with similar relative gut lengths had considerable gut microbiome similarity. Notably, the SL (short relative gut length) group, as zoobenthos and zooplankton specialists, was abundant in Proteobacteria and was less abundant in Firmicutes than in the ML (medium relative gut length) and LL (long relative gut length) groups. These fish could extract nutrients from aquatic plants and algae. Additionally, we found the relative abundance of and to be positively correlated with host relative gut length but negatively correlated with the relative abundance of , , , and , and host-relative gut length. We also show a positive linear relationship between host gut microbiome carbohydrate metabolism and relative gut length, while the amino acid and lipid metabolism of the gut microbiome was negatively correlated with host-relative gut length. In addition, omnivorous species competing for resources improve their ecological adaptability through the specialization of gut length, which is closely related to variation in the synergy of the gut microbiome. Above all, specialized gut microbiota and associated gut morphologies enable fish to variably tolerate resource fluctuation and improve the utilization efficiency of nutrient extraction from challenging food resources.
PubMed: 36016786
DOI: 10.3389/fmicb.2022.936601 -
Frontiers in Immunology 2022The present study was conducted to investigate the effects of dietary inclusion of protein hydrolysates on growth performance, digestive enzyme activities, protein...
The present study was conducted to investigate the effects of dietary inclusion of protein hydrolysates on growth performance, digestive enzyme activities, protein metabolism, and intestinal health in larval largemouth bass (). The experimental feeding trial presented in this study was based on five isonitrogenous and isolipidic diets formulated with graded inclusion levels of protein hydrolysates, and it showed that protein hydrolysates improved growth performance, reduced larval deformity rate, and increased the activity of digestive enzymes, including pepsin and trypsin. Gene expression results revealed that the supplementation of protein hydrolysates upregulated the expression of intestinal amino acid transporters LAT2 and peptide transporter 2 (PepT2), as well as the amino acid transporters LAT1 in muscle. Dietary provision of protein hydrolysates activated the target of rapamycin (TOR) pathway including the up-regulation of TOR and AKT1, and down-regulation of 4EBP1. Additionally, the expression of genes involved in the amino acids response (AAR) pathway, ATF4 and REDD1, were inhibited. Protein hydrolysates inhibited the transcription of some pro-inflammatory cytokines, including IL-8 and 5-LOX, but promoted the expression of anti-inflammatory cytokines TGF-β and IL-10. The 16S rRNA analysis, using V3-V4 region, indicated that dietary protein hydrolysates supplementation reduced the diversity of the intestine microbial community, increased the enrichment of and reduced the enrichment of at the genus level. In summary, protein hydrolysates have been shown to be an active and useful supplement to positively complement other protein sources in the diets for largemouth bass larvae, and this study provided novel insights on the beneficial roles and possible mechanisms of action of dietary protein hydrolysates in improving the overall performance of fish larvae.
Topics: Animal Feed; Animals; Bass; Cytokines; Gastrointestinal Microbiome; Intestines; Larva; Protein Hydrolysates; RNA, Ribosomal, 16S
PubMed: 35928824
DOI: 10.3389/fimmu.2022.913024 -
Frontiers in Microbiology 2022An 8-week feeding trial was conducted using the rice field eel () with six isonitrogenous and isoenergetic experimental diets of basic feed supplemented with different...
An 8-week feeding trial was conducted using the rice field eel () with six isonitrogenous and isoenergetic experimental diets of basic feed supplemented with different levels of methionine (0, 2, 4, 6, 8, or 10 g/kg). This study built upon previous research findings that showed dietary methionine restriction (M0, 0 g/kg) inhibited hepatic fatty acid metabolism and intestinal fatty acid transportation, but both are improved by dietary supplementation with a suitable level of methionine (M8, 8 g/kg). Hence, M0 and M8 were selected to investigate how methionine regulates the gut microbiota and lipidomics of . Compared with M0, values for gut bacterial Sobs, Shannon, ACE, and Chao1 indices of M8 were remarkably increased ( < 0.05), with , , and the dominant phyla and , , and the main genera in the community under the M0 vs. M8 treatments. However, compared with M0, the proportion of phyla consisting of decreased in M8, as did the and at the genus level; conversely, the proportions corresponding to , , and phyla increased in M8, as did the and genera. Many edges appeared in the circus and networks, demonstrating the interspecies interactions among different operational taxonomic units (OTUs). In addition, various OTUs within the same phylum were clustered within one module. Cooperative interactions were predominant in the two networks, while competitive interactions were prevalent in their submodules. Gut microbiota mainly played roles in nutrition (lipid, amino acid, and carbohydrate) transport and metabolism under the M0 vs. M8 treatments. The PLS-DA scores indicated a significant difference in the main lipidomic components between the M0 and M8 treatment groups. Namely, the TG(26:0/16:0/17:0), TG(28:0/16:0/16:0), TG(26:0/16:0/16:0), and TG(30:0/16:0/16:0)-among others-comprising the gut content were reduced under the M8 treatment ( < 0.001). The genus was positively correlated with TG(18:1/18:1/22:5), TG(16:0/17:0/18:1), TG(18:0/18:1/20:3), and other compounds, yet negatively correlated with TG(18:0/17:0/20:0), TG(16:0/17:0/24:0), and TG(16:0/16:0/24:0), among others as well. According to the lipidomics analysis, the predicted KEGG pathways mainly included lipid and glycan biosynthesis and metabolism, and digestive, sensory, and immune systems. In conclusion, methionine restriction disturbed the microbial community balance and induced microbial dysfunctions, whereas methionine supplementation improved the homeostasis of gut microbiota and lipid metabolism of the rice eel.
PubMed: 35875587
DOI: 10.3389/fmicb.2022.917051 -
Frontiers in Immunology 2022Various bacterial diseases have caused great economic losses to the high-density and intensive aquaculture industry; however, the pathogenic mechanism underlying the...
Various bacterial diseases have caused great economic losses to the high-density and intensive aquaculture industry; however, the pathogenic mechanism underlying the large-scale challenged to caused by many bacteria remain unclear, making the prevention and treatment of these diseases difficult. In the present study, we isolated a bacterial strain from having a typical bacterial disease and named it Cc2021. Through subsequent morphological observations, a regression challenge, biochemical identification, and 16S rRNA gene sequence analysis, we determined Cc2021 to be . Subsequently, we comprehensively investigated the pathogenicity of in through a regression challenge and assessed the underlying the pathogenic mechanism. Mortality results revealed that is highly pathogenic and infects various tissues throughout the body, resulting in edema of the liver, spleen, and body and head kidneys. Histopathological analysis revealed obvious inflammation, bleeding, and necrosis in the intestine, spleen, and head kidney. The body's immune tissues actively produce complement C3, superoxide dismutase, and lysozyme after a challenge to resist bacterial invasion. With regard to the underlying pathogenesis of , comparative transcriptome analysis revealed 876 upregulated genes and 828 downregulated genes in the intestine of after the challenge. Analysis of differentially expressed unigenes revealed the involvement of major immune pathways, particularly the TNF signaling pathway, interleukin (IL)-17 signaling pathway, and Toll-like receptor signaling pathway. The present study provides new valuable information on the immune system and defense mechanisms of .
Topics: Animals; Carps; Plesiomonas; RNA, Ribosomal, 16S; Transcriptome; Virulence
PubMed: 35844551
DOI: 10.3389/fimmu.2022.872896 -
Microorganisms Jun 2022Histamine is a toxic biogenic amine commonly found in seafood products or their derivatives. This metabolite is produced by histamine-producing bacteria (HPB) such as ,... (Review)
Review
Histamine is a toxic biogenic amine commonly found in seafood products or their derivatives. This metabolite is produced by histamine-producing bacteria (HPB) such as , , , , , , , , spp., , , , , , , , , , spp., , , , , , and In this review, the role of these bacteria in histamine production in fish and seafood products with consequences for human food poisoning following consumption are discussed. In addition, methods to control their activity in countering histamine production are proposed.
PubMed: 35744715
DOI: 10.3390/microorganisms10061197 -
Environment International Aug 2022Perfluorooctane sulfonate (PFOS) has been reported to induce hepatotoxicity in wildlife and humans. Novel PFOS alternatives have been widely used following restrictions...
Perfluorooctane sulfonate (PFOS) has been reported to induce hepatotoxicity in wildlife and humans. Novel PFOS alternatives have been widely used following restrictions on PFOS, but little is known about their potential toxicity. Here, the first comprehensive investigation on the chronic hepatotoxicity and underlying molecular mechanisms of PFOS, 6:2Cl-PFESA (F-53B), and sodium p-perfluorous nonenoxybenzene sulfonate (OBS) was carried out on adult zebrafish through a histopathological examination, biochemical measurement, and multi-omics analysis. PFOS and its alternatives caused changes in liver histopathology and liver function indices in the order of F-53B > PFOS > OBS, which was consistent with their concentration in the liver. In silico modeling and transcriptional profiles suggested that the aberrant hepatic lipid metabolism induced by F-53B and PFOS was initiated by the action on peroxisome proliferator-activated receptor γ (PPARγ), which triggered changes in downstream genes transcription and led to an imbalance between lipid synthesis and expenditure. Gut microbiome analysis provided another novel mechanistic perspective that changes in the abundance of Legionella, Ralstonia, Brevundimonas, Alphaproteobacteria, Plesiomonas, and Hyphomicrobium might link to alterations in the PPAR pathway based on their significant correlation. This study provides insight into the molecular mechanisms of hepatotoxicity induced by PFOS and its novel alternatives and highlights the need for concern about their environmental exposure risks.
PubMed: 35738203
DOI: 10.1016/j.envint.2022.107351 -
Frontiers in Microbiology 2022With strong demand for aquatic products, as well as a rapid decrease in global fishery resources and capture fisheries, domesticating animals to provide more...
With strong demand for aquatic products, as well as a rapid decrease in global fishery resources and capture fisheries, domesticating animals to provide more high-quality proteins is meaningful for humans. Freshwater drum () is widely distributed in the wild habitats of North America. However, the research on and the feed domestication with diets composed of artificial compounds remains unclear. In this study, a 4-month feeding domestication experiment was conducted with larvae to evaluate the underlying mechanism and molecular targets responsible for alternations in the ingestion performance. The results indicated that a significant increase in the final body weight was exhibited by the feed domesticated group (DOM, 114.8 g) when compared to the group that did not ingest the feed (WT, 5.3 g) as the latest version we raised From the result, the final body weight exhibited significant increase between unfavorable with the feed (WT, 5.3 g) and feed domesticated group (DOM, 114.8 g). In addition, the enzyme activity of digestive enzymes like amylase, lipase, and trypsin was increased in DOM. Genes related to appetite and perception, such as , , and , were activated in DOM. 16s rRNA gene sequencing analysis revealed that sp. increased from 58.74% to 89.77% in DOM, which accounts for the dominant upregulated microbial community at the genus level, followed by . Analogously, , , and also accounted for the down-regulated microbes in the diversity. Transcriptome and RT-PCR analysis revealed that feed domestication significantly improved protein digestion and absorption, inhibited apoptosis by AGE-RAGE signaling, and activated extracellular matrix remodeling by relaxin signaling. Integrated analysis of the microbiome and host transcriptome revealed that mediated ingestion capacity, protein utilization, and cellular homeostasis might be the underlying mechanism under feed domestication. These results indicate and its key genes relating to food ingestion and digestion could serve as the molecular targets for feed domestication and sustainable development in .
PubMed: 35722333
DOI: 10.3389/fmicb.2022.861705 -
Veterinary World Apr 2022One of the emerging viral diseases in freshwater fish is Tilapia lake virus (TiLV), which infects all stages of fish and results in mass mortalities. Previously, a TiLV...
BACKGROUND AND AIM
One of the emerging viral diseases in freshwater fish is Tilapia lake virus (TiLV), which infects all stages of fish and results in mass mortalities. Previously, a TiLV case was detected in the wild environment in Malaysia that involved tilapia and tinfoil barb. Hence, this study aimed to determine the presence of TiLV in wild tilapia () as well as tinfoil barbs () at the similar lake after the initial outbreak in year 2017.
MATERIALS AND METHODS
Both fish species were sampled from this lake at a month interval for two years and subjected to TiLV detection using reverse transcriptase-polymerase chain reaction and cell culture isolation. Concurrently, bacterial isolation and water quality measurements were performed to deduce their correlation with TiLV occurrence. Other wild fish species and mollusk were also occasionally sampled during the fish inventory activity at this lake. The fish's weight, length, and associated clinical signs were noted throughout the entire study period.
RESULTS
Mortality was not observed throughout the whole study period, and results indicated a moderate to high prevalence of TiLV infection in both tilapia and tinfoil barbs. There was no correlation between TiLV infection with the isolation rate of opportunistic bacteria such as ., and . in the study site. At the same time, the Pearson correlation test revealed a moderate negative correlation between the water pH with the presence of TiLV (R=-0.4472; p<0.05) and a moderate positive correlation between the water iron content with the monthly detection of . in wild tilapia. This is contrary to tinfoil barbs, where there was a moderate negative correlation between the water iron content with the monthly isolation of . (R=-0.5190; p<0.05). Furthermore, isolation of TiLV on cell culture-induced viral invasion was resulted in the cytopathic effects.
CONCLUSIONS
Our results suggest that the wild fish may harbor TiLV for an extended period following a massive die-off event in 2017 without any obvious clinical signs and mortality. The persistency of viruses in the wild may need continuous and effective control as well as prevention strategies.
PubMed: 35698523
DOI: 10.14202/vetworld.2022.1097-1106 -
Scientific Reports Jun 2022Tamarindus indica is one of the tropical medicinal plants that has been attributed curative potential of numerous diseases by many rural dwellers. This study was...
Tamarindus indica is one of the tropical medicinal plants that has been attributed curative potential of numerous diseases by many rural dwellers. This study was designed to evaluate the antioxidant, antibacterial activities and also to determine the various chemical constituents responsible for its pharmacological activities. The methanol extract of Tamarindus indica fruit pulp was analyzed by Gas Chromatography/Mass Spectrometer to determine the volatile compounds present. The antioxidant activities were performed using DPPH and FRAP method and the antibacterial activity was tested against some common pathogens by macro broth dilution method. The GCMS analysis shows the presence of 37 compounds, out of which 14 had their peak area percentages ≥ 1% and only two compounds had no reported pharmacological activities. Most of the bioactive compounds including 5-Hydroxymethylfurfural (31.06%)-3-O-Methyl-d-glucose (16.31%), 1,6-anhydro-β-D-Glucopyranose (9.95%), 5-methyl-Furancarboxaldehyde (3.2%), Triethylenediamine (1.17%), 1-(2-furanyl)-1-Propcanone (2.18%), Methyl 2-furoate (3.14%), Levoglucosenone (3.21%), methyl ester-Hepta-2,4-dienoic acid, (8.85%), 2,3-dihydro-3,5-dihydrox-4H-Pyran-4-one (3.4%), O-α-D-glucopyranosyl-(1.fwdarw.3)-β-D-fructofuranosyl-α-D-Glucopyranoside (2.18%), n-Hexadecanoic acid (1.38%), 2-Heptanol, acetate (1.29%), 5-[(5-methyl-2-fur-2-Furancarboxaldehyde (1.08%), 3-Methyl-2-furoic acid (1.05%) and cis-Vaccenic acid (2.85%)have been reported with different activities such as antibacterial, antifungal, antitubercular, anticancer, antioxidant and other prophylactic activities. The extract demonstrated inhibitory potential against all tested pathogen. However, Plesiomonas shigellosis ATCC 15903 and Bacillus pumillus ATCC 14884 are more sensitive with the MIC of 0.22 and 0.44 mg/ml respectively. The antioxidant activity was relatively low due to the low phenolic content of the extract. This shows that there is a strong correlation between antioxidant activities and phenolic content. GC-MS analysis revealed the presence of bioactive phytoconstituents with various biological activities and this justifies the rationale behind its usage as a curative therapy by many local dwellers.
Topics: Anti-Bacterial Agents; Antioxidants; Methanol; Phenols; Plant Extracts; Tamarindus
PubMed: 35676439
DOI: 10.1038/s41598-022-13716-x