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1.
Genome Biol Evol ; 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32058545

RESUMO

Members of genus Martes provide early warning signals about forest ecosystem health and are designated as a Management Indicator Species (MIS). As one of the most widespread members in Martes, the sable (Martes zibellina) is a circumboreal small predator found throughout all taiga zoogeographical zones of Eurasia and shows distinct population differentiation and morphological variations. To support further studies on striking local adaptation and population evolution, we present the first sable genome, assembled de novo from an individual originating in the Great Khingan Mountains (China). The assembled genome is 2.42 Gb, consisting of 15,814 scaffolds with a scaffold N50 of 5.20 Mb. Searches for complete Mammalia BUSCO (Benchmarking Universal Single-Copy Ortholog) gene groups found that 95.15% of the curated single copy orthologs were assembled as complete, suggesting a high level of completeness of the genome. We totally predicted 19,413 protein-coding genes, and 0.82 Gb of repeat sequences were annotated. We also detected 1,257 olfactory receptor genes and found more functional olfactory receptor genes in sable than in other Mustelidae species, which provide a possible genetic explanation for the acute sense of smell of the sable for searching the preys under deep snow. Phylogenetic analyses revealed that the ferret (Mustela putorius furo) and sea otter (Enhydra lutris) form a clade that is sister to the sable, which was dated approximately 16.4 million years ago (Mya). Overall, our study provided the first reference genome for research in a broad range of areas including local adaptations, population evolution, conservation and management for sable.

3.
Chemosphere ; 247: 125814, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31927186

RESUMO

The extreme high CO2 in industrial exhaust gas cannot be tolerated by microalgae is the key challenge for the application of microalgae in CO2 bio-sequestration. To provide better insights for this challenge, we chose one high CO2 tolerant (Chlorella sp. LAMB 31) and non-tolerant (Chlorella sp. LAMB 122) Chlorella sp. to examine their different CO2 fixation and carbon allocation responses to 40% CO2. The results indicated LAMB 31 had a 24-h "lag phase" of biomass increase, during which the transition from PSII-PSI and the increase of lipid synthesis happened to acclimate high CO2 conditions, followed by the increase of pigments synthesis, carbon fixation rates and polysaccharide productions. However, no acclimating mechanism was observed in LAMB 122, whose biomass, photosynthesis and material synthesis were all gradually collapsed under 40% CO2. Finally, four parameters including Chl a, polysaccharides, carbon fixation rates and MDA were selected to be good physiological biomarkers for high CO2 tolerant strains screenings in the future.

4.
Chemosphere ; 240: 124821, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31546185

RESUMO

Anthropogenic CO2 emissions lead to seawater acidification that reportedly exerts deleterious impacts on marine organisms, especially on calcifying organisms such as mussels. A 21-day experiment focusing on the impacts of seawater acidification on the blue mussel, Mytilus edulis, was performed in this study, within which two acidifying treatments, CO2 enrichment and HCl addition, were applied. Two acidifying pH values (7.7 and 7.1) and the alteration of the key physiological processes of ingestion and digestion were estimated. To thoroughly investigate the impact of acidification on mussels, a histopathological study approach was adopted. The results showed that: (1) Seawater acidification induced either by CO2 enrichment or HCl addition impaired the gill structure. Transmission electron microscope (TEM) results suggested that the most obvious impacts were inflammatory lesions and edema, while more distinct alterations, including endoplasmic reticulum edema, nuclear condensation and chromatin plate-like condensation, were placed in the CO2-treated groups compared to HCl-treated specimens. The ciliary activity of the CO2 group was significantly inhibited simultaneously, leading to an obstacle in food intake. (2) Seawater acidification prominently damaged the structure of digestive glands, and the enzymatic activities of amylase, protease and lipase significantly decreased, which might indicate that the digestion was suppressed. The negative impacts induced by the CO2 group were more severe than that by the HCl group. The present results suggest that acidification interferes with the processes of ingestion and digestion, which potentially inhibits the energy intake of mussels.


Assuntos
Ácidos/efeitos adversos , Dióxido de Carbono/efeitos adversos , Ácido Clorídrico/efeitos adversos , Mytilus edulis/efeitos dos fármacos , Água do Mar/química , Ácidos/química , Animais , Dióxido de Carbono/farmacologia , Homeostase/efeitos dos fármacos , Ácido Clorídrico/farmacologia
5.
Chemosphere ; 244: 125477, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31821926

RESUMO

Ulva prolifera green tide is a serious marine ecological problem in China's coastal areas, with recurrent outbreaks occurring annually during late spring and summer since 2007. Marine bacteria communities are closely linked with important ecological functions in coastal environments. Hence, the succession of bacterial community structures in seawater and sediments during the outbreak and extinction stages of U. prolifera green tide were studied in this paper. The results revealed that: (1) the outbreak of a green tide led to changes in the bacterial community structure and a reduction in the abundance and diversity of the bacterial community in the Qingdao offshore region. This change was more significant in sediments than in seawater. (2) The bacterial assemblage appeared to be dominated by members of Deltaproteobacteria, Bacteroidia and Flavobacteria in sediment, and reductions in the relative abundance of Flavobacteria and Alphaproteobacteria were also observed in seawater after the green tide outbreak. There was also a high similarity in species composition of bacteria in sediment (extinction stage) and seawater (outbreak stage). (3) The outbreak of the U. prolifera affected the abundance of functional bacterial communities in the offshore environment such as SRB (sulfate-reducing bacteria), CFB (Cytophaga-Flavobacter-Bacteroides), heterotrophic bacteria and the potentially algicidal bacteria Alteromonadaceae. Overall, U. prolifera affects aquatic ecosystem secondary production, biogenic geochemical cycles and the growth of other seaweeds in Qingdao offshore areas by driving variations in functional bacterial communities.

6.
Zootaxa ; 4614(2): zootaxa.4614.2.7, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31716383

RESUMO

Two new species of the family Xyalidae from the Laizhou Bay of the Bohai Sea, China are described and illustrated herein. Daptonema papillifera sp. nov. is characterized by relatively small body size, L-shaped spicules with a large cephalate proximal end, triangular gubernaculum with a dorsal apophysis, 5-6 conjoint precloacal cuticularized spines and two ventral papillae located at the middle of the tail. Daptonema papillifera sp. nov. is easily distinguished from the other species in this genus by having 5-6 conjoint precloacal cuticularized spines and two ventral caudal papillae. Pseudosteineria anteramphida sp. nov. is characterized by eight groups of long subcephalic setae located posterior to amphideal fovea, curved slender spicules with cephalate proximal end and tapered distal end, tubular gubernaculum without apophysis, precloacal supplements absent, and a short precloacal seta present. In comparison with its most similar congeneric species, P. ventropapillata Tchesunov, 2000 the new species differs in having smaller body, not jointed cephalic setae, absence of precloacal supplements and absence of gubernacular apophysis.


Assuntos
Nematoides , Animais , Baías , Tamanho Corporal , China , Cromadoria
7.
Antibiotics (Basel) ; 8(3)2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31323873

RESUMO

Vibrio species are a significant causative of mass mortality in mariculture worldwide, which can quickly accumulate in live food and transmit into the larval gut. With restrictions on the use of antibiotics in aquaculture, finding a proper solution to reduce the risk of Vibriosis is vital. This study aimed to evaluate the susceptibility of Vibrio harveyi, V. campbellii, V. anguillarum, and V. parahaemolyticus to twenty-six bacterial and yeast strains and use the beneficial ones to enrich live food (Branchiopod, Artemia franciscana, rotifer, Brachionus plicatilis and copepod, Tigriopus japonicus). Thus, a modified disk diffusion method was applied. After a susceptibility assay, the bacteria and yeast beneficial in suppressing the Vibrio species were labeled by fluorescent stain and used to measure the accumulation potential in different live foods. Also, the beneficial bacteria and yeast were used to enrich live foods, and then the count of loaded Vibrio was estimated after 5, 10, 15, and 20 hours by the serial dilution method. From the total bacteria and yeast strains that were used, Candida parapsilosis, Pseudoalteromonas flavipulchra, Lactobacillus sakei, Bacillus natto, and B. amyloliquefaciens inhibited all four Vibrio species. The results of microbial labeling showed that L. sakei in Artemia, C. parapsilosis in rotifers, and V. harveyi in copepods had the highest accumulation rate. The results of the estimation of loaded Vibrio in different live foods also showed that the use of beneficial bacteria and yeast each significantly reduced the count of Vibrio. Application of bacteria and yeast to suppress pathogenic Vibrio maybe a sustainable method for preventing this pathogen from harmfully invading aquaculture and may also aid in reducing the chances of antibiotic resistance in pathogenic Vibrio.

8.
Front Plant Sci ; 10: 648, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31178877

RESUMO

Large-scale green tides have occurred continuously in the Yellow Sea of China from 2007 to 2018, and the causative species of the Yellow Sea green tide (YSGT) is Ulva prolifera. The thalli form floated thallus mats, and the thalli from different layers of the thallus mat suffer significantly different environmental conditions. In the present study, the environmental conditions of the surface layer (SL), middle layer (ML), and lower layer (LL) of the thallus mat from mid-June (Stage I) to mid-July (Stage II) were simulated. Photosynthetic traits and antioxidant systems were measured. The results showed that (1) photoprotective [non-photochemical quenching (NPQ) and cyclic electron transport (CEF)] and antioxidant systems both play important roles in protecting against abiotic factors in U. prolifera. (2) Cooperation between NPQ and CEF was observed in the ML group; CEF and the antioxidant system in the SL group work synergistically to protect the thalli. Furthermore, an inferred spatiotemporal attribute regarding the YSGT is presented: the significant changes in abiotic factors on the sea surface can easily affect the thalli of SL and ML from mid-June to mid-July, and those of LL can be affected in mid-July. This cooperation combined with the spatiotemporal attributes offers an explanation for the annual occurrence of the YSGT. HIGHLIGHTS     -Adaptive mechanisms of Ulva prolifera against abiotic factors.     -Cooperation between photosynthetic and antioxidant systems.     -Spatiotemporal attributes regarding the Yellow Sea green tide are presented.

9.
Aquat Toxicol ; 212: 20-27, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31039523

RESUMO

Polybrominated diphenyl ethers (PBDEs), a series of highly persistent organic pollutants (POPs), are ubiquitous in marine ecosystems. As key primary producers, microalgae are of great importance on evaluating the environmental outcome of PBDEs pollution. In this study, the toxic mechanisms of BDE-47 on the marine diatom Thalassiosira pseudonana were evaluated by measuring multiple physiological processes. Three concentrations of BDE-47 (25, 15 and 5 µg L-1) were used along with two controls (blank: no BDE-47 or DMSO; negative control: only DMSO). Experiments lasted 144 h (6 days), in which the actual BDE-47 concentrations, cell densities, nutrient (nitrate and phosphate) uptake, pigment compositions, photosynthetic physiology, cell morphology and cellular contents (organic carbon and nitrogen) were measured at 12-48 h intervals. The toxic mechanisms of BDE-47 on T. pseudonana cells were evaluated by measuring multiple physiological processes including photosynthesis, nutrient uptake, cellular material synthesis and cell cycle progressions. The cell divisions of T. pseudonana were severely inhibited by the stress of BDE-47, but the photosynthetic parameters were much less declined and recovered earlier than the cell divisions in the same BDE-47 treatments. The unsuppressed uptake rates of nutrients, increased cell volume and cellular contents indicated the cellular material synthesis proceeded normally. Finally, we found that the cell cycle was arrested in G2/M phase under the stress of BDE-47, we thus concluded that the inhibition of cell divisions by BDE-47 was not due to the lack of energy or cellular materials, where the cell cycle arrest happened; this might be the most important toxicological outcome.


Assuntos
Diatomáceas/efeitos dos fármacos , Diatomáceas/fisiologia , Éteres Difenil Halogenados/toxicidade , Fenômenos Fisiológicos/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Carbono/metabolismo , Ciclo Celular/efeitos dos fármacos , Diatomáceas/citologia , Diatomáceas/crescimento & desenvolvimento , Nitrogênio/metabolismo , Fotossíntese/efeitos dos fármacos , Complexo de Proteína do Fotossistema II/metabolismo , Pigmentos Biológicos/metabolismo , Estresse Fisiológico/efeitos dos fármacos
10.
Int J Biol Macromol ; 134: 1045-1051, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31129211

RESUMO

Pattern recognition receptors (PRRs) play a crucial role in the host's innate immune system. Among the PPRs, the RIG-I-like (RLRs) and NOD-like receptors (NLRs) are two important subgroups. To understand the role of RLRs (RIG-I, MDA5, LGP2) and NLRs (NOD1, NLRC3, NLRX1, NOD2) in reptilian evolution, we identified six genes from reptilian genomes. A total of 168 putative genes were identified from 28 reptile species, including 141 intact genes, 25 partial genes and two pseudogenes. Interestingly, the NOD2 gene was absent in all reptile species. Phylogenetic results showed that all genes were divided into four major clades corresponding to their traditional taxonomic groups, indicating that these genes are conserved in reptiles. Evolutionary analyses detected positive selection in six genes. Most of the positively selected sites (50/76) were located in known functional domains, reflecting their critical and particular contributions to host defense during reptilian evolution. Branch model analysis showed that NLRs were under different evolutionary forces, while the RLRs were not, suggesting that semiaquatic species and terrestrial species faced different environmental pathogens, leading to different adaptations. Moreover, the positively selected sites identified in MDA5 using the branch-site model among semiaquatic reptiles, suggested their involvement in adaptation to semiaquatic environments.


Assuntos
Adaptação Biológica , Proteína DEAD-box 58/genética , Evolução Molecular , Genoma , Genômica , Proteínas NLR/genética , Répteis/genética , Animais , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Répteis/classificação
11.
Aquat Toxicol ; 208: 168-178, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30677712

RESUMO

As a newly emerging environmental contaminant, tributyl phosphate (TBP) is an additive flame retardant of high production volume that is frequently detected in biota and the environment. Despite evidence that TBP is a potential threat to marine organisms, ecotoxicology data for TBP in marine organisms at low trophic levels are scarce. In this study, the acute toxicological effect of TBP on the marine phytoplankton Phaeodactylum tricornutum was thoroughly investigated, and the possible mechanism was explored. The results showed that TBP at concentrations ≥0.2 mg L-1 significantly inhibited P. tricornutum growth in a clear dose-response manner, with 72-h EC10, EC20, EC50 and EC90 values of 0.067, 0.101, 0.219 and 0.716 mg L-1, respectively. Algal cells treated with TBP exhibited distorted shapes, ruptured cell membranes and damaged organelles, especially mitochondria. Additionally, apoptosis was triggered, followed by a decrease in mitochondrial membrane potential, indicating that cellular damage occurred during exposure. Although the activities of two antioxidant enzymes, superoxide peroxidase and catalase, were upregulated by TBP at 1.2 mg L-1, excess reactive oxygen species (ROS) and malondialdehyde still accumulated in algal cells after exposure, suggesting that the cells experienced oxidative stress. Moreover, both growth inhibition and apoptosis were positively correlated with ROS levels and were ameliorated by pretreatment with the ROS scavenger N-acetyl-l-cysteine. Taken together, the results indicate that TBP exposure leads to growth inhibition and cellular damage in P. tricornutum, and a ROS-mediated pathway might contribute to these observed toxicological effects.


Assuntos
Diatomáceas/metabolismo , Organofosfatos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Acetilcisteína/farmacologia , Apoptose/efeitos dos fármacos , Catalase/metabolismo , Diatomáceas/efeitos dos fármacos , Diatomáceas/crescimento & desenvolvimento , Diatomáceas/ultraestrutura , Malondialdeído/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fitoplâncton/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/toxicidade
12.
Int J Biol Macromol ; 126: 1093-1098, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30611807

RESUMO

Aquaporin (AQP) genes are widely distributed in plants, unicellular organisms, invertebrates and vertebrates. They play a critical role in the transport of water and other solutes across cell membranes. AQP genes have been identified and studied in many species but the AQPs of reptiles are unknown. Newly obtained genome assemblies provide an opportunity to identify the complete AQPs set and explore the evolutionary relationship of these genes. A total of 212 putative AQP genes were identified from 18 reptile species, including 20 partial genes and 192 intact genes. Phylogenetic results showed that 193 AQP genes could be classified into three major clades according to their subfamily. The divergence or phylogenetic distance between reptile AQP genes was closely related to traditional taxonomic groupings. Evolutionary analysis indicated the presence of positively selected sites in the AQP3 (P = 0.0104⁎⁎) and AQP7 (P = 0.0202⁎⁎) among land reptiles, suggesting their relationship to terrestrial environment adaptation.


Assuntos
Aquaporinas/genética , Estudo de Associação Genômica Ampla , Família Multigênica , Répteis/genética , Animais , Filogenia , Seleção Genética
13.
Sci Total Environ ; 656: 778-788, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30530147

RESUMO

The brominated flame retardant, 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), is well documented to exert potential negative impacts on different marine biota. However, the responsible mechanism remains unknown. The rainbow trout gonadal cell line RTG-2 was used as a model, and the mechanism and pathway underlying BDE-47 (6, 12.5 and 25 µM)-induced apoptosis and toxicity were examined in vitro. Apoptosis occurred in the RTG-2 cells exposed to BDE-47 in a clear concentration-dependent manner. The morphology of the mitochondrial alterations was observed using transmission electron microscopy. BDE-47 exposure decreased the cellular mitochondrial membrane potential, increased the cytochrome c released into the cytoplasm and elevated Fas protein expression. The mRNA expressions of Fas-associated death domain-containing protein (FADD), CHOP and GRP78 were also elevated, and similar increases were found in the activities of intracellular caspase-8, caspase-12, caspase-9 and caspase-3. These results indicated that the mitochondrial, endoplasmic reticulum and death-receptor pathways were involved in apoptosis in RTG-2 cells following BDE-47 exposure. ROS and Ca2+ were responsible for these changes because their overproduction was detected prior to apoptosis. However, the addition of the ROS scavenger N-acetyl-l-cysteine (NAC) and the intracellular calcium chelator (acetoxymethyl)-1,2-bis-(o-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid (BAPTA-AM) did not significantly alleviate the apoptosis rate. The results of the present study show that BDE-47 exposure induced apoptosis in RTG-2 cells via ROS- and Ca2-mediated mitochondrial, endoplasmic reticulum and death-receptor apoptotic pathways.


Assuntos
Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Éteres Difenil Halogenados/toxicidade , Oncorhynchus mykiss/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Linhagem Celular , Relação Dose-Resposta a Droga
14.
Microbiologyopen ; 8(3): e00650, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-29877059

RESUMO

The relationship between the internal microbiome of an individual organism and that of its external environment has been little investigated in freshwater ecosystems. Thus, this is an area of interest in freshwater fish biology. Along with the genotype of the fish host, external environment plays an important role in determining the composition of the internal microbiome. Here, we characterized the variability of the microbiome of wild Crucian carp (Carassius auratus), along with those of their surrounding environments (water and mud). We found that each environment had distinct bacterial communities, with varying composition and structure. The primary bacterial phyla identified in the Crucian carp gut were Fusobacteria and Proteobacteria (90% of all bacterial phyla identified); the primary genera identified were Cetobacterium, Aeromonas, and Plesiomonas (85% of all bacterial phyla identified). We identified 1,739 operational taxonomic units (OTUs) in the Crucian carp gut, 1,703 in water, and 5,322 in mud. Each environment had unique OTUs, but the fewest unique OTUs (97) were found in the Crucian carp gut. There were significant differences in the relative abundances of different bacterial phyla in the different environments. It may be that only bacterial phyla vital for efficient fish function (e.g., immune response or metabolism), such as Fusobacteria and Proteobacteria, are retained in the Crucian carp gut.


Assuntos
Água Doce/microbiologia , Sedimentos Geológicos/microbiologia , Carpa Dourada/microbiologia , Microbiota , Animais , Exposição Ambiental
15.
Sci Rep ; 8(1): 10541, 2018 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-30002474

RESUMO

Marine organisms especially sessile invertebrates, such as soft corals, gorgonians and sponges, can survive in the competitive environment mainly relying on their second metabolites with chemoecological effects including allelopathy and algal growth inhibition. It is well known that the microscale models are urgently needed in marine chemoecology assessment to evaluate the algal growth inhibition activity of trace quantity natural products. In this work, a microalgal growth inhibition model was established for microalgal inhibition evaluation of marine natural products with 96-well microplate by automatic fluorescence observation using microplate reader. Subsequently, this model was applied to bioassay-guided isolation and preliminary bioactivity screening of the secondary metabolites from soft corals, gorgonians, sponges and their symbiotic microbes collected from the South China Sea. As a result, fifteen compounds (1‒15) were found to exhibit microalgal growth inhibition activities against at least one of marine microalgae, Karenia mikimotoi, Isochrysis galbana, and Heterosigma akashiwo. Specifically, altersolanol C (13) demonstrated potent activity against K. mikimotoi with the 96h-EC50 value of 1.16 µg/mL, more than four times stronger than that of the positive control K2Cr2O7. It was suggested that the microalgal growth inhibition microscale model is suitable for bioassay-guided isolation and preliminary bioactivity screening of marine natural products.


Assuntos
Bioensaio/métodos , Produtos Biológicos/farmacologia , Proliferação Nociva de Algas/efeitos dos fármacos , Microalgas/efeitos dos fármacos , Animais , Antozoários/metabolismo , Produtos Biológicos/metabolismo , Clorofila/análise , Microalgas/química , Microalgas/crescimento & desenvolvimento , Poríferos/metabolismo
16.
Environ Pollut ; 240: 549-556, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29758529

RESUMO

Naphthenic acids (NAs) account for 1-2% of crude oil and represent its main acidic component. However, the aquatoxic effects of NAs on marine phytoplankton and their ecological risks have remained largely unknown. Using the marine microalgae Phaeodactylum tricornutum and Platymonas helgolandica var. tsingtaoensis as the target, we studied the effects of NAs on their growth, cell morphology and physiological characteristics. The cell density decreased as the concentrations of NAs increased, indicating that they had an adverse effect on growth of the investigated algae in a concentration-dependent manner. Moreover, scanning electron microscopy revealed NAs exposure caused damage such as deformed cells, shrunken surface and ruptured cell structures. Exposure to NAs at higher concentrations for 48 h significantly increased the content of chlorophyll (Chl) a and b in P. tricornutum, but decreased their levels in P. helgolandica var. tsingtaoensis. NAs with concentrations no higher than 4 mg/L gradually enhanced the Chl fluorescence (ChlF) parameters and decreased the ChlF parameters at higher concentrations for the two marine microalgae. Additionally, NAs induced hormesis on photosynthetic efficiency of the two microalgae and also have the species difference in their aquatic toxicity. Overall, the results of this study provide a better understanding of the physiological responses of phytoplankton and will enable better risk assessments of NAs.


Assuntos
Ácidos Carboxílicos/toxicidade , Clorófitas/efeitos dos fármacos , Diatomáceas/efeitos dos fármacos , Microalgas/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Clorofila/análise , Clorofila A , Diatomáceas/fisiologia , Petróleo/análise , Petróleo/metabolismo , Fotossíntese/efeitos dos fármacos
17.
Recent Pat Anticancer Drug Discov ; 13(3): 368-377, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29676234

RESUMO

BACKGROUND: Phytoestrogens have been proposed as replaceable medicines for climacteric hormone replacement therapy, on the basis of EP3138562 and US5516528. However, recent studies demonstrated that phytoestrogens might promote the proliferation of breast cancer cells, which is rooted in their estrogenic activity. Acacetin, as one phytoestrogen, has been reported to exhibit estrogenic activity. But the effect of acacetin on breast cancer cells proliferation and its mechanism has not been explored. OBJECTIVE: This study aims to evaluate the effects of acacetin on breast cancer MCF-7 cells proliferation and to explore its possible mechanism. METHODS: Sulforhodamine B (SRB) assay was used to test the proliferation rate of MCF-7 cells. Flow cytometry was utilized to determine cell cycle. RT-qPCR and western blot were employed to evaluate the expressions of proliferation-related factors in mRNA and protein levels. RESULTS: According to SRB assay and flow cytometric analysis, low dose of acacetin from 10-3 to 1µM promoted the MCF-7 cells proliferation in a dose-dependent and time-dependent manner. Moreover, the expressions of cell cycle-related molecules, ERK1/2 and PI3K/AKT were increased after treatment with acacetin, while the increases were effectively reversed by ER antagonist ICI 182,780. Further studies showed that acacetin notably induced increasing mRNA and proteins levels of ERα, which were strongly reversed by ERα antagonist MPP. CONCLUSION: Low dose of acacetin from 10-3 µM to µM promoted the proliferation of MCF-7 cells through the ERK/PI3K/AKT pathway and its downstream cyclin signaling. And ERα is mainly responsible for acacetin promoting proliferation in MCF-7 cells.


Assuntos
Proliferação de Células/efeitos dos fármacos , Ciclinas/metabolismo , Flavonas/administração & dosagem , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proliferação de Células/fisiologia , Relação Dose-Resposta a Droga , Humanos , Sistema de Sinalização das MAP Quinases/fisiologia , Células MCF-7 , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
18.
Sci Total Environ ; 628-629: 562-572, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29453184

RESUMO

Ecotoxicological methods were applied in the present study, and the marine rotifer Brachionus plicatilis was used as the toxic endpoint to depict what occurred when 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) was combined with solar ultraviolet-B radiation (UV-B). B. plicatilis was exposed to three different combination methods of BDE-47 and UV-B at an equal toxicity ratio, including normal rotifer co-cultured with UV-B-irradiated BDE-47 (known as Method I), UV-B-irradiated rotifer co-cultured with BDE-47 exposure (known as Method II) and normal rotifer co-cultured with the simultaneous addition of BDE-47 and UV-B irradiation (known as Method III). Acute and chronic experiments were preformed to determine the toxicity differentiation according to the growth and reproduction changes in the rotifer. Twenty-four-hour acute experiments showed that the modes of three combined methods changed from antagonism to additive, to synergistic with the concentration/dose increment, and the contribution rates of Method I and Method II to Method III were calculated by approximately 40.4% and 59.6%, respectively. Chronic exposure to either the single stressor or the combination of stressors inhibited the growth and reproduction of the rotifer, demonstrating the inhibition of the population growth rate and the decrease in the larvae production. Three combined groups presented more serious damages compared to groups with single stress exposure, and the ascending sequence of toxicity was Method I

Assuntos
Éteres Difenil Halogenados/toxicidade , Processos Fotoquímicos , Rotíferos/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Fotólise , Transtornos de Fotossensibilidade , Reprodução
19.
Int J Biol Macromol ; 109: 698-703, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29292152

RESUMO

Toll-like receptors (TLRs) encoded by the TLR multigene family play an important role in initial pathogen recognition in vertebrates. Among the TLRs, TLR2 and TLR4 may be of particular importance to reptiles. In order to study the evolutionary patterns and structural characteristics of TLRs, we explored the available genomes of several representative members of reptiles. 25 TLR2 genes and 19 TLR4 genes from reptiles were obtained in this study. Phylogenetic results showed that the TLR2 gene duplication occurred in several species. Evolutionary analysis by at least two methods identified 30 and 13 common positively selected codons in TLR2 and TLR4, respectively. Most positively selected sites of TLR2 and TLR4 were located in the Leucine-rich repeat (LRRs). Branch model analysis showed that TLR2 genes were under different evolutionary forces in reptiles, while the TLR4 genes showed no significant selection pressure. The different evolutionary adaptation of TLR2 and TLR4 among the reptiles might be due to their different function in recognizing bacteria. Overall, we explored the structure and evolution of TLR2 and TLR4 genes in reptiles for the first time. Our study revealed valuable information regarding TLR2 and TLR4 in reptiles, and provided novel insights into the conservation concern of natural populations.


Assuntos
Evolução Molecular , Duplicação Gênica , Genômica , Répteis/genética , Seleção Genética , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Animais , Genômica/métodos , Filogenia , Répteis/imunologia , Análise de Sequência de DNA , Receptor 2 Toll-Like/química , Receptor 4 Toll-Like/química
20.
Chemosphere ; 192: 66-74, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29100123

RESUMO

Saxitoxin (STX), a paralytic shellfish toxin (PST) produced from toxic bloom-forming dinoflagellates, was selected to comparatively investigate the induction of cytotoxicity and apoptosis and a possible mechanism based on changes in the antioxidant defence system of two cellular strains: the mouse neuroblastoma cell line Neuro-2a and the rainbow trout fish cell line RTG-2. Increasing concentrations of STX (0-256 nM) presented little cytotoxic or apoptotic effects on the two cell lines. Measurements of cellular viability, lethal ratio and LDH leakage showed slight changes in Neuro-2a and RTG-2 cells (p > 0.05), and similar results were observed for cellular morphology and apoptotic rates. The contents of the main reactive oxygen species (ROS) components, superoxide anion (O2-) and hydrogen peroxide (H2O2), were markedly increased in Neuro-2a cell with STX exposure at middle (15 nM) and high (150 nM) concentrations (p < 0.05), and the simultaneous increase of the ratio of reduced/oxidized glutathione (GSH/GSSG) (p < 0.05) inferred the occurrence of oxidative stress. However, little difference was observed in all treated groups of RTG-2 cells. The activities of three antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR), were significantly enhanced in Neuro-2a cells in the middle and high concentration groups (p < 0.05), while glutathione peroxidase (GPX) obviously decreased (p < 0.05) in all treated groups. Little change was found in RTG-2 cells with the same exposures. These results provided evidence that STX exposure altered the redox status of Neuro-2a cells and resulted in oxidative stress, but the same exposure exerted little effect on RTG-2 cells. Therefore, Neuro-2a cells are more sensitive than reproductive cells to STX exposure, and the antioxidant systems appears to be partly responsible for this differentiation response.


Assuntos
Espécies Reativas de Oxigênio/metabolismo , Saxitoxina/toxicidade , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Catalase/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Glutationa Peroxidase/metabolismo , Camundongos , Oncorhynchus mykiss , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo
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