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1.
Nat Immunol ; 25(6): 969-980, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38831104

RESUMO

Rare genetic variants in toll-like receptor 7 (TLR7) are known to cause lupus in humans and mice. UNC93B1 is a transmembrane protein that regulates TLR7 localization into endosomes. In the present study, we identify two new variants in UNC93B1 (T314A, located proximally to the TLR7 transmembrane domain, and V117L) in a cohort of east Asian patients with childhood-onset systemic lupus erythematosus. The V117L variant was associated with increased expression of type I interferons and NF-κB-dependent cytokines in patient plasma and immortalized B cells. THP-1 cells expressing the variant UNC93B1 alleles exhibited exaggerated responses to stimulation of TLR7/-8, but not TLR3 or TLR9, which could be inhibited by targeting the downstream signaling molecules, IRAK1/-4. Heterozygous mice expressing the orthologous Unc93b1V117L variant developed a spontaneous lupus-like disease that was more severe in homozygotes and again hyperresponsive to TLR7 stimulation. Together, this work formally identifies genetic variants in UNC93B1 that can predispose to childhood-onset systemic lupus erythematosus.


Assuntos
Predisposição Genética para Doença , Lúpus Eritematoso Sistêmico , Receptor 7 Toll-Like , Lúpus Eritematoso Sistêmico/genética , Humanos , Animais , Receptor 7 Toll-Like/genética , Receptor 7 Toll-Like/metabolismo , Camundongos , Criança , Feminino , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Masculino , Idade de Início , Variação Genética , NF-kappa B/metabolismo , Linfócitos B/imunologia , Linfócitos B/metabolismo , Adolescente , Células THP-1 , Interferon Tipo I/metabolismo
3.
Can J Microbiol ; 69(7): 242-250, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36971259

RESUMO

Polyculture operations in freshwater aquaculture ponds can disrupt microbial communities. High-throughput sequencing was used to assess the impact of polyculture operations on bacterial and three sub-microeukaryote communities (fungi, zooplankton, and eukaryotic phytoplankton) in Penaeus vannamei aquaculture ponds containing oriental river prawns and giant freshwater prawns, respectively. The results showed that the bacterial community was less sensitive than the microeukaryote communities to both the polyculture activity and environmental variations. The polyculture of giant freshwater prawns rather than oriental river prawns was the primary factor affecting the beta diversity of the three sub-microeukaryote communities. This may be due to the larger biomass of the polyculture varieties of giant freshwater prawns compared with oriental river prawns. The polyculture activity of giant freshwater prawns with a higher density and that of oriental river prawns with a lower density increased the stochasticity of the community assembly of the three sub-microeukaryote communities. It also affected the topological properties of the microbial communities, including greater correlations between ecosystem elements, and reducing the correlations among zooplanktons. The eukaryotic phytoplankton was the only microbial community that could also be explained by nutrient variation (mainly the total nitrogen). This highlights the potential role of the eukaryotic phytoplankton as a suitable indicator of the effects of nutrient input into ecosystems.


Assuntos
Microbiota , Penaeidae , Animais , Lagoas/microbiologia , Água , Penaeidae/microbiologia , Aquicultura , Bactérias/genética , Fitoplâncton
4.
Bull Environ Contam Toxicol ; 106(5): 866-872, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33768336

RESUMO

Orthogonal experiments were used to simulate the enrofloxacin (ENR) elimination dynamic in deeper water of aquaculture. Two factors at values common in fishery water (temperature of 20°C, 25°C, and 30°C; pH of 5, 7, and 9) were studied. The degradation of ENR in the nine treatment groups ranged from 44.7 to 80.1%. Variance analysis indicated that pH had a strong impact on the elimination of ENR, while temperature changes showed little effect. The ENR removal rate was highest at a combination of 25°C and pH 5. The optimal conditions of eliminating ENR were performed for exploring the generation of ciprofloxacin (CIP), which indicated that higher ENR concentrations led to the production of greater amounts of CIP. The half-time of ENR was increased 2.02-times in the ENR concentrations increasing from 20 to 2000 ng/mL. This study could increase our understanding of the behaviors of ENR and CIP during the aquaculture process.


Assuntos
Fluoroquinolonas , Água , Antibacterianos , Aquicultura , Enrofloxacina , Concentração de Íons de Hidrogênio , Temperatura
5.
Indian J Microbiol ; 61(4): 475-486, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34744203

RESUMO

Microorganisms are sensitive to changes in the external environment and are often used as indicators to monitor and reflect water quality. Using Illumina MiSeq sequencing, the characteristics of the microbial community in Shihou Lake water at different time points were analyzed and the key environmental factors affecting the bacterial community were identified. The microbial community diversity in Shihou Lake water was rich and showed significant differences over time. The main bacterial phyla were the Cyanobacteria, Proteobacteria, Actinobacteria, Verrucomicrobia, Bacteroidetes, Chloroflexi, Planctomycetes, Firmicutes, Chlorobi, WS6 and Saccharibacteria. The relative abundance of these major phyla in the sample accounted for 97.83%-99.07% of the total abundance; Cyanobacteria had the highest relative abundance, accounting for 13.07%-44.61% of the total, and the abundance of each dominant phylum was significantly different at different time points. The Shannon and Simpson indexes showed that the diversity of each month was as follows: August > October > July > September > November. The Chao1 and Ace indexes indicated that the order of richness was: November > October > July > August > September. Beta diversity analysis found significant differences in the samples from month to month. Environmental factors such as temperature, total nitrogen, chlorophyll-a, permanganate index, nitrite, pH and ammonia nitrogen had significant effects on microbial community structure.

6.
Arch Microbiol ; 202(1): 43-53, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31463601

RESUMO

To evaluate the changes in bacterial diversity at various time points under resveratrol supplementation, we aimed to investigate the diversification of gut microbiota and the changes in total genetic diversity. We performed 16S rDNA gene sequencing at different time points (15, 30, and 45 days) to analyze the gut microbiota of tilapia. Fusobacteria, Proteobacteria, and Bacteroidetes (15 days) or Cyanobacteria (30 and 45 days) were found to be the three most abundant phyla. Cyanobacteria (15 and 30 days), Proteobacteria (15 days), Firmicutes and Chlamydiae (30 and 45 days), Planctomycetes (30 days), Bacteroidetes, Actinobacteria, and Fusobacteria (45 days) in the 0.05 g/kg RES group increased as compared to that in the controls. Proteobacteria and Cyanobacteria significantly decreased and increased at 30 and 45 days, respectively, while the reverse pattern was observed at 15 days. The Bacteroidetes:Firmicutes and Proteobacteria:Cyanobacteria ratios were significantly increased (15 and 45 days, P < 0.05) and decreased (30 days, P < 0.05). RES supplementation did not affect the richness and diversity of the gut microbiota in tilapia. Our findings may contribute to the development of strategies for the management of diseases.


Assuntos
Bactérias , Ciclídeos/microbiologia , Suplementos Nutricionais , Microbioma Gastrointestinal/efeitos dos fármacos , Resveratrol/farmacologia , Animais , Bactérias/genética , Biodiversidade , RNA Ribossômico 16S/genética
7.
Environ Toxicol ; 35(11): 1202-1211, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32621570

RESUMO

Polybrominated diphenyl ethers (PBDEs) are ubiquitous and prolific contaminant in both the abiotic and biotic environment because of the wide industrial applications of these chemicals. In the present study, the effects of 2,2',4,4'-tetrabrominateddiphenyl ether (BDE-47) and 2,2',4,4',5,5'-hexabromodiphenyl ether (BDE-153) exposure on the induction of hepatic oxidative stress, DNA damage, and the expression of apoptosis-related genes in adult zebrafish were investigated. The activities of antioxidant enzymes, such as catalase and superoxide dimutase, significantly increased when adult zebrafish was exposed to various concentrations of BDE-47 and BDE-153 for 7 and 15 days. BDE-47 and BDE-153 elicited significant alterations in zebrafish 7-Ethoxyresorufin-O-deethylase activity at 3, 7, or 15 days of exposure. In addition, the significant increase in comet assay parameters of zebrafish hepatocytes in a concentration-dependent manner indicated BDE-47 and BDE-153 induced DNA damage, probably due to observed oxidative stress. Furthermore, a monotonically upregulation of p53 and Caspase3, which are apoptotic-regulated genes, and decreased expression ratio of the anti-apoptotic B-cell lymphoma/leukaemia-2 and Bcl2-associated X protein genes for all BDE-47 and BDE-153 treatments at 7 and 15 days indicated apoptosis induction in zebrafish liver. Our findings help elucidate the mechanisms of BDE-47- and BDE-153-induced toxicity in zebrafish hepatocytes.


Assuntos
Éteres Difenil Halogenados/toxicidade , Bifenil Polibromatos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Caspase 3 , Ensaio Cometa , Citocromo P-450 CYP1A1/metabolismo , Dano ao DNA , Éteres Difenil Halogenados/metabolismo , Hepatócitos/metabolismo , Fígado/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peixe-Zebra/metabolismo
8.
Fish Shellfish Immunol ; 90: 466-476, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31004800

RESUMO

We performed 16S rDNA sequencing of tilapia fecal samples to analyze changes in tilapia gut contents after cultivation of the fish in the presence of sandwich-like floating beds of Chinese medicinal herbs (5 and 10% planting-areas; 5% Polygonum cuspidatum). The interactive effects between water quality and blood and hepatic pro- and anti-inflammatory concentrations were also assessed. Our results showed that the water quality (i.e., NO3--N, NO2--N, TP removal rates) improved, and the abundance of Chloroflexi and Cyanobacteria increased. The abundance of Bacteroidetes, Verrucomicrobia, Saccharibacteria, and Actinobacteria showed both significant seasonal decreases and increases in the presence of P. cuspidatum (increases in August and decreases in July). Fish blood and hepatic IL-10 and IFN-γ levels (together with fish sampled in September) significantly increased in the P. cuspidatum group sampled in August, while those of TNF-α (10% sandwich-like, P. cuspidatum), IL-1ß (P. cuspidatum), IL-8 (5% sandwich-like in September, S905S) significantly decreased. Heat shock proteins 60 and 70 levels significantly increased in the P. cuspidatum group, and complement C3 and C4 concentrations significantly increased in S905S. This study demonstrated that enhanced immunity through the regulation of pro- and anti-inflammatory proteins was sustained throughout development until harvest, particularly in fish grown with P. cuspidatum.


Assuntos
Ciclídeos/imunologia , Microbioma Gastrointestinal , Imunidade Inata , Plantas Medicinais/metabolismo , RNA Ribossômico 16S/análise , Qualidade da Água , Animais , Ciclídeos/crescimento & desenvolvimento , Ciclídeos/microbiologia , DNA Ribossômico/análise , Fezes/química , Fezes/microbiologia , Masculino , Medicina Tradicional Chinesa , Estações do Ano , Análise de Sequência de DNA/veterinária
9.
Can J Microbiol ; 65(7): 522-529, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30921521

RESUMO

We carried out sequencing of samples cultivated in floating beds with different Chinese medicinal herbs (Control, Houttuynia cordata Thunb., Polygonum cuspidatum, and a combination of H. cordata with Ipomoea aquatica Forssk.; named groups A, B, C, D, respectively) to analyze changes in the composition of gut microbiota of tilapia feces. Fusobacteria (ranging from 49.0% to 73.3%), Firmicutes (12.3%-37.8%), and Proteobacteria (5.1%-23.0%) were found to be the most dominant phyla present in all samples. The operational taxonomic units and the Ace and Chao1 indices of groups A and D were significantly higher than those of group C. Polygonum cuspidatum decreased the species richness and diversity of microbial communities in tilapia intestinal feces. The phylum WCHB1-60, order Enterobacteriales, and genus Plesiomonas significantly decreased (in group A); the species Plesiomonas shigelloides significantly decreased (in groups B and C); and the genus Leucobacter significantly increased (in group D) when compared with the control. The relative abundance of the class Verrucomicrobiae (groups B vs C) significantly decreased. In the presence of I. aquatica, the phylum Bacteroidetes significantly decreased, while the genera Leucobacter and Pelotomaculum significantly increased. The ratio of Bacteroidetes to Firmicutes was significantly higher in groups B and C relative to the controls, while it decreased significantly in group D. The algae (i.e., Anabaena and Microcystis) and beneficial pathogenic bacteria decreased in groups C and D, respectively. In addition, Enterovibrio decreased in all treatment groups. The present data demonstrate that floating bed cultivation with Chinese medicinal herbs significantly alters the gut microbiota of tilapia, which may enhance its immune activity.


Assuntos
Fallopia japonica , Microbioma Gastrointestinal , Houttuynia , Ipomoea , Tilápia/microbiologia , Animais , Bactérias/classificação , Bacteroidetes/isolamento & purificação , Fezes/microbiologia , Firmicutes/isolamento & purificação , Intestinos/microbiologia , Masculino , Microbiota , Proteobactérias/isolamento & purificação , Tilápia/crescimento & desenvolvimento
10.
Fish Shellfish Immunol ; 77: 200-207, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29574130

RESUMO

The genetically improved farmed tilapia (GIFT, Oreochromis niloticus) is cultured widely for production of freshwater fish in China, while streptococcosis, likely related to pathogenic infections, occurs frequently in juvenile, mother, and operated GIFT. The gut microbiota plays an important role in nutrient digestibility in animals, and resveratrol (RES) has been used in feed for different freshwater fish species. Therefore, understanding changes in the tilapia gut microbiota across different concentrations of dietary RES supplementation is extremely important. The gut microbiota population in tilapia at 45 d after supplementation with different concentrations (0, 0.025, 0.05, 0.1 g/kg) of dietary RES was assessed by 16S rDNA gene sequencing. A total of 5445 operational taxonomic units were identified from all samples, and 14 phyla and 81 families were identified from all fecal samples. The bacteria of the phylum Firmicutes were significantly enriched in the 0.025 g/kg RES group when compared with the controls. Proteobacteria, Firmicutes and Cyanobacteria were the most dominant three phyla in all samples. With the increasing concentrations, the proportion of beneficial microbial taxa (Acetobacteraceae and Methylobacteriaceae) increased, whereas the proportion of harmful microbial taxa decreased, eg. Streptococcaceae except for 0.1 g/kg RES groups. RES did not affect the richness and diversity in tilapia gut microbiota. These findings provide information on the diversity and differences in GIFT gut microbiota database, and may contribute to developing strategies for management of diseases and long-term sustainability of O. niloticus culture.


Assuntos
Ciclídeos/fisiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Estilbenos/metabolismo , Ração Animal/análise , Animais , Ciclídeos/microbiologia , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Masculino , Distribuição Aleatória , Resveratrol , Estilbenos/efeitos adversos
11.
Antonie Van Leeuwenhoek ; 111(1): 115-124, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28840355

RESUMO

Aquaculture ponds represent ecologically relevant environments to study the community composition and diversity of methanogenic assemblages, as well as their interactions with cultivated species and chemical indicators. In this study, aquaculture ponds with crab (Eriocheir sinensis), oriental river prawn (Macrobrachium nipponense), perch (Micropterus salmonides) and Wuchang fish (Parabramis pekinensis) were sampled, and Illumina high-throughput sequencing was used to investigate the methanogenic communities. The results revealed that the abundant methanogenic orders in surface sediment were Methanomicrobiales, Methanosarcinales and Methanocellales. The relative abundance of Methanocellales was higher in crab and prawn ponds as compared to other ponds. Methanogenic 16S rRNA gene abundance and beta diversity of the community was affected by the cultivated species. Methanogenic communities in aquaculture ponds with higher contents of total nitrogen and organic matter had decreased species richness, while those with higher contents of ammonia and nitrite had an overall decreased abundance of methanogens and their respective diversities. Overall, in addition to the differences in cultivated species, the consequent differences in farming practices including the types and amounts of feeds used, the contents of total nitrogen, organic matter, ammonia and nitrite could all influence the methanogenic community in surface sediment of aquaculture ponds.


Assuntos
Euryarchaeota/classificação , Água Doce/microbiologia , Sedimentos Geológicos/microbiologia , Microbiologia da Água , Biodiversidade
12.
Ecotoxicol Environ Saf ; 147: 447-454, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28892663

RESUMO

The GIFT (Genetically Improved Farmed Tilapia) tilapia, Oreochromis niloticus, is cultured widely for the production of freshwater fish in China. Streptococcosis, which is related to pathogenic infections, occurs frequently in juvenile and adult female GIFT individuals. Resveratrol (RES) has been used in feed to control these infections in freshwater tilapia. To address the effects of RES on tilapia, we used high-throughput RNA sequencing technology (RNA-Seq, HiSeq. 2500) to explore the global transcriptomic response and specific involvement of hepatic mRNA of juvenile O. niloticus fed with diets containing different concentrations of (0, 0.025, 0.05, and 0.1g/kg) RES. A total of > 24,513,018 clean reads were generated and then assembled into 23,244 unigenes. The unigenes were annotated by comparing them against non-redundant protein sequence (Nr), non-redundant nucleotide (Nt), Swiss-Prot, Pfam, Gene Ontology database (GO), Clusters of Orthologous Groups (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, and 12,578 unigenes were annotated to the GO database. A total of 1444 (0.025g/kg RES), 1526 (0.05g/kg RES), and 3135 (0.1g/kg RES) genes were detected as significant differentially expressed genes (DEGs), when compared with the controls. A total of 6 (0.025 vs 0.05g/kg RES), 19 (0.025 vs 0.1g/kg RES), and 124 (0.05 vs 0.1g/kg RES) genes were detected as significant DEGs. Six genes, including dnah7x1, sox4, fam46a, hsp90a, ddit4, and nmrk2, were associated with an immune response. These findings provide information on the innate immunity of GIFT and might contribute to the development of strategies for the effective management of diseases and long-term sustainability of O. niloticus culture.


Assuntos
Ciclídeos/metabolismo , Fígado/efeitos dos fármacos , Estilbenos/farmacologia , Transcriptoma/efeitos dos fármacos , Animais , China , Ciclídeos/imunologia , Dieta , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Imunidade Inata/efeitos dos fármacos , Fígado/metabolismo , Resveratrol
13.
World J Microbiol Biotechnol ; 34(3): 43, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29492679

RESUMO

Archaea, like the bacterial communities are gradually being realized as key players in the biogeochemical progress of water ecosystems. In this study, tilapia aquaculture ponds were used for an in-depth understanding of archaeal community compositions in water and surface sediment. Some of the main functions, as well as the communities' response patterns, to time variations, pond differences and some physio-chemical parameters were investigated. The results revealed the dominant phylum in both the water and surface sediment, as Euryarchaeota, while, the most abundant classes were: Halobacteria and Methanomicrobia respectively. Significant differences in the archaeal community compositions in the water and surface sediment, were observed in the early stages of cultivation, which became minimal at the later stage of the GIFT tilapia cultivation. Additionally to the differences in the most abundant classes, more OTUs were observed in water samples than in surface sediment samples. The methane generation could be attributed to the large proportion of methanogens found in both pond water and in the surface sediment. Furthermore, the archaeal community compositions in water and the surface sediment were shaped mainly by temporal variations and pond differences respectively. In the pond water, the archaeal community compositions were highly co-related to the concentration changes of ammonia, sulfate and total nitrogen; while in the surface sediment, the correlation to the content changes was significant in total phosphorus. The archaeal community compositions in surface sediment should be considered as an indicator for future environmental capacity studies in aquaculture.


Assuntos
Aquicultura , Archaea/classificação , Consórcios Microbianos , Lagoas/microbiologia , Tilápia/microbiologia , Amônia , Animais , Archaea/genética , Archaea/isolamento & purificação , Biodiversidade , Fenômenos Químicos , China , DNA Arqueal , Euryarchaeota , Água Doce/análise , Água Doce/microbiologia , Sedimentos Geológicos/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala , Metano/biossíntese , Nitrogênio , Filogenia , RNA Ribossômico 16S/genética , Sulfatos , Microbiologia da Água
14.
Fish Shellfish Immunol ; 64: 49-55, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28279789

RESUMO

Dietary supplementation with rutin may have some pharmacological qualities including anti-inflammatory effects. Kupffer cell activation resulted in increased transcription of pro- and anti-inflammatory cytokines. The main purpose of this study was to investigate the pro- and anti-inflammatory activities in juvenile freshwater tilapia, Oreochromis niloticus, in response to 0.1 or 0.3 g/kg dietary supplementation of rutin. Results showed that hepatic IgM, anti-inflammatory-cytokines, and pro-inflammatory cytokines were significantly decreased in groups treated with high doses of rutin. Hepatic IgM and anti-inflammatory cytokines (IL-10 and IFN-γ) transcripts were significantly decreased, whereas the transcripts of the pro-inflammatory cytokines, TNFα and IL-1ß were significantly decreased, whereas IL-8 was significantly increased. The number of Kupffer cells in rutin-treated groups was significantly decreased, and scanning electron micrographs showed that rutin enriched the number of gut microvilli and secretion pits. With the phenomena of cell apoptosis occurred in the rutin groups, the present study demonstrated that optimum levels of rutin may be beneficial but excessive level may cause liver impairment, which may be absorbed by the gut and then transported to the liver.


Assuntos
Anti-Inflamatórios/imunologia , Ciclídeos/imunologia , Citocinas/metabolismo , Suplementos Nutricionais , Proteínas de Peixes/metabolismo , Rutina/imunologia , Ração Animal/análise , Animais , Anti-Inflamatórios/administração & dosagem , Dieta/veterinária , Suplementos Nutricionais/análise , Fígado/imunologia , Distribuição Aleatória , Rutina/administração & dosagem
15.
Ecotoxicol Environ Saf ; 144: 252-257, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28633103

RESUMO

Antibiotics are widely used in aquaculture and therefore may be present as a dietary risk in cultured aquatic products. Using the Tai Lake Basin as a study area, we assessed the presence of 15 antibiotics in 5 widely cultured aquatic species using a newly developed dietary risk ranking approach. By assigning scores to each factor involved in the ranking matrices, the scores of dietary risks per antibiotic and per aquatic species were calculated. The results indicated that fluoroquinolone antibiotics posed the highest dietary risk in all aquatic species. Then, the total scores per aquatic species were summed by all 15 antibiotic scores of antibiotics, it was found that Crab (Eriocheir sinensis) had the highest dietary risks. Finally, the most concerned antibiotic category and aquatic species were selected. This study highlighted the importance of dietary risk ranking in the production and consumption of cultured aquatic products around Tai Lake.


Assuntos
Antibacterianos/análise , Aquicultura/métodos , Braquiúros/química , Lagos/química , Poluentes Químicos da Água/análise , Animais , China , Dieta , Humanos , Medição de Risco
16.
Environ Toxicol ; 32(7): 1869-1877, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28251797

RESUMO

Tilapia were exposed to sub-lethal concentrations of 0, 0.2, 2, 20 or 200 µg/L for 30 days, then transferred to methomyl-free water for 18 days. E2 , T, 11-KTand VTG in serum were examined. There were no significant changes in all the parameters in serum of tilapia exposed to 0.2 µg/L and 2 µg/L methomyl compared to the control. However, 20 µg/L and 200 µg/L have the potential to disrupt the endocrine system of male tilapia, as shown by its ability to increase VTG and E2 and decrease T and 11-KT in serum. Thus it would appear the no observed adverse effect level for sexual steroid hormones of methomyl is lower than 2 µg/L. Recovery data showed that the effects produced by 20µg/L were reversible but not at 200µg/L. Furthermore, the sensitivity of above parameters to methomyl followed the order of VTG>E2 >11-KT>T>GSI, suggesting VTG being the better biomarkers.


Assuntos
Disruptores Endócrinos/toxicidade , Hormônios Esteroides Gonadais/sangue , Inseticidas/toxicidade , Metomil/toxicidade , Tilápia/metabolismo , Vitelogeninas/sangue , Poluentes Químicos da Água/toxicidade , Animais , Masculino , Nível de Efeito Adverso não Observado
17.
World J Microbiol Biotechnol ; 33(1): 1, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27832505

RESUMO

Bacterial community compositions in the surface sediment of tilapia ponds and their responses to pond characteristics or seasonal variations were investigated. For that, three ponds with different stocking densities were selected to collect the samples. And the method of Illumina high-throughput sequencing was used to amplify the bacterial 16S rRNA genes. A total of 662, 876 valid reads and 5649 operational taxonomic units were obtained. Further analysis showed that the dominant phyla in all three ponds were Proteobacteria, Bacteroidetes, Chloroflexi, and Acidobacteria. The phyla Planctomycetes, Firmicutes, Chlorobi, and Spirochaetae were also relatively abundant. Among the eight phyla, the abundances of only Proteobacteria, Bacteroidetes, Firmicutes, and Spirochaetae were affected by seasonal variations, while seven of these (with the exception of Acidobacteria) were affected by pond differences. A comprehensive analysis of the richness and diversity of the bacterial 16S rRNA gene, and of the similarity in bacterial community composition in sediment also showed that the communities in tilapia pond sediment were shaped more by pond differences than by seasonal variations. Linear discriminant analysis further indicated that the influences of pond characteristics on sediment bacterial communities might be related to feed coefficients and stocking densities of genetically improved farmed tilapia (GIFT).


Assuntos
Bactérias/classificação , Sedimentos Geológicos/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Lagoas/microbiologia , Tilápia/microbiologia , Animais , Bactérias/isolamento & purificação , Biodiversidade , Análise Discriminante , Filogenia , RNA Ribossômico 16S/genética , Estações do Ano , Análise de Sequência de RNA , Tilápia/crescimento & desenvolvimento
18.
Bull Environ Contam Toxicol ; 98(4): 562-566, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28236009

RESUMO

In the present study, Nile tilapia (Oreochromis niloticus) were used to assess the endocrine disruption potential of Microcytis aeruginosa. Male Nile tilapia were exposed to lyophilized M. aeruginosa or purified microcystin-LR (8.3 µg/L) for 28 days. The levels of serum hormones (17ß-estradiol and testosterone) and transcripts of selected genes in the hypothalamus-pituitary-gonadal-liver axis were analyzed. The results showed that serum hormones were significantly up-regulated, and transcripts of 13 genes (GHRH, PACAP, GH, GHR1, GHR2, IGF1, IGF2, CYP19a, CYP19b, 3ß-HSD1, 20ß-HSD, 17ß-HSD1 and 17ß-HSD8) were significantly altered after Microcytis exposure. These results indicate that fish reproduction can be altered in a Microcystis bloom-contaminated aquatic environment.


Assuntos
Expressão Gênica/efeitos dos fármacos , Gônadas/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Fígado/efeitos dos fármacos , Microcistinas/toxicidade , Microcystis/química , Tilápia/genética , 17-Hidroxiesteroide Desidrogenases , Animais , Ciclídeos/genética , Disruptores Endócrinos/toxicidade , Estradiol/sangue , Liofilização , Masculino , Toxinas Marinhas , Testosterona/sangue , Tilápia/sangue , Regulação para Cima/efeitos dos fármacos
19.
Ecotoxicol Environ Saf ; 128: 143-52, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26938152

RESUMO

The effects of synthetic androgen 17α-methyltestosterone (MT) on endocrine impairment were examined in crucian carp. Immature 7-month old mono-female Pengze crucian carp (Pcc) F2 offspring were exposed to 50 and 100 µg/L of MT (week 2, 4, and 8). Gonadosomatic index, hepatosomatic index and intestine weight altered considerably and oocyte development was repressed. In the treatment groups, ovarian 11-ketotestosterone decreased, whereas 17ß-estradiol and testosterone increased, and ovarian aromatase activities increased at week 4. However, in the brain tissue, those values significantly decreased. Quantitative RT-PCR analysis demonstrated changes in steroid receptor genes and upregulation of steroidogenic genes (Pcc-3bhsd, Pcc-11bhsd2 Pcc-cyp11a1), while the other three steroidogenic genes (Pcc-cyp17a1, Pcc-cyp19a1a and Pcc-star) decreased from week 4 to week 8. Ovarian, hepatic Pcc-vtg B and vitellogenin concentration increased in both 50 and 100 µg/L of MT exposure groups. This study adds further information regarding the effects of androgens on the development of previtellogenic oocytes, which suggests that MT could directly target estrogen signaling pathway, or indirectly affect steroidogenesis and vitellogenesis.


Assuntos
Androgênios/toxicidade , Carpas/crescimento & desenvolvimento , Disruptores Endócrinos/toxicidade , Sistema Endócrino/efeitos dos fármacos , Metiltestosterona/toxicidade , Vitelogênese/efeitos dos fármacos , Animais , Aromatase/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Carpas/genética , Carpas/metabolismo , Sistema Endócrino/metabolismo , Estradiol/genética , Estradiol/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Óvulo/efeitos dos fármacos , Óvulo/metabolismo , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo , Caracteres Sexuais , Testosterona/genética , Testosterona/metabolismo , Vitelogênese/genética , Vitelogeninas/genética , Vitelogeninas/metabolismo
20.
Environ Toxicol ; 30(4): 483-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24273132

RESUMO

Tilapia were exposed to sublethal concentrations of 0, 0.2, 2, 20, or 200 µg/L for 30 days, and then transferred to methomyl-free water for 18 days. GST, GPx, GR, GSH, and GSSG in tilapia serum were examined at 0, 6, 12, 18, 24, and 30 days after methomyl exposure and at 18 days after transferring to methomyl-free water. There were no significant changes in antioxidants activities and contents in serum of tilapia exposed to 0.2 µg/L. Significant increases in GST, GR, GPx, and GSSG accompanied by a decrease in GSH were observed following methomyl exposure to 2, 20, or 200 µg/L, suggesting the presence of oxidative stress. Thus, it would appear the 0.2 µg/L methomyl might be considered the no observed adverse effect level. Recovery data showed that the effects produced by lower concentration of 20 µg/L were reversible but not at the higher 200 µg/L concentration.


Assuntos
Antioxidantes/metabolismo , Ciclídeos/metabolismo , Glutationa/metabolismo , Inseticidas/toxicidade , Metomil/toxicidade , Animais , Masculino , Nível de Efeito Adverso não Observado , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
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