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1.
Chemosphere ; 239: 124759, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31518920

RESUMO

Ammonia is an important environmental stress factor in aquaculture. Long-term ammonia stress could affect the normal growth, and also increase the risk for the occurrence of various diseases. In order to learn the mechanism that ammonia caused the outbreak of the shrimp disease, transcriptomics and metabolomics approaches were used to analyze the differential expressions of the genes in hemocytes and different metabolites in the serum of the Pacific white shrimp Litopenaeus vannamei under ammonia exposure. Transcriptional analysis showed that 17 cell apoptosis related genes, seven phagocytosis related genes, 10 immunity related genes and seven cell cycle and lipid metabolism related genes showed differential expressions after ammonia exposure. Metabolomics analysis on the serum showed that 25 differential metabolites were identified in positive and negative ion patterns. They are involved in purine metabolism, amino acids metabolism and lipid metabolism. Injection of two up-regulated metabolites triethanolamine and oxypurinol to normal shrimp could induce apoptosis in normal shrimp. The total hemocytes counts in shrimp showed a significant decrease and the apoptotic cell ratio increased significantly under ammonia exposure. These results suggested that ammonia exposure increased the apoptosis of hemocytes, which affected the immunity of shrimp, and thus caused susceptibility to pathogenic infection. These data will help us understand the mechanism of ammonia stress leading to the immunity decline of shrimp.


Assuntos
Amônia/toxicidade , Hemócitos/efeitos dos fármacos , Penaeidae/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Aminoácidos/genética , Aminoácidos/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Aquicultura , Perfilação da Expressão Gênica , Hemócitos/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolômica , Penaeidae/fisiologia , Fagocitose/efeitos dos fármacos
2.
Chemosphere ; 238: 124526, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31466002

RESUMO

In this paper, for the first time, we show in chloraminated systems, the chloramine decaying proteins (CDP) play an important role in bulk water and biomass (biofilm) in resisting disinfectant. Extracellular polymeric substances in biofilm/biomass are known to protect microbes from disinfectants and toxic materials, but the exact mechanism(s) is/are not known. Starting with the seed from a nitrifying chloraminated reactor, two 5 L reactors were fed intermittently with either chloramine or ammonia containing nutrient solution. The degree of nitrification increased with time in both reactors despite an increase in soluble CDP in the chloraminated reactor, while soluble CDP decreased in the ammoniated one. The suspended biomass collected after eight months of operation from chloraminated reactor contained CDP and responded to short-term chloramine stress (1.5 h with initial 1.5 mg-Cl2·L-1) by the additional production of soluble CDP. The suspended biomass from ammoniated reactor neither contained CDP nor produced soluble CDP as a stress response. The production, release and accumulation of CDP in biomass (biofilm) could be one of several mechanisms microbes use to defend against disinfectants (stress). The new understanding will pave the way for better disinfection management and better design of experiments.


Assuntos
Biofilmes , Biomassa , Reatores Biológicos/microbiologia , Cloraminas/metabolismo , Cloraminas/farmacologia , Proteínas/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Amônia/metabolismo , Biofilmes/efeitos dos fármacos , Desinfetantes/farmacologia , Nitrificação
3.
Artigo em Inglês | MEDLINE | ID: mdl-31669372

RESUMO

The razor clam Sinonovacula constricta is a commercial benthic bivalve, and burrows the deeper cave than the other buried benthic bivalves. Due to the little exchange of seawater and to anoxic conditions, S. constricta is exposed to considerable amounts of sulfide during low tide, but exhibits strong sulfide tolerance. Mitochondrial sulfide oxidation is a particular defense strategy against sulfide toxicity of sulfide-tolerant organisms, for which sulfide:quinone oxidoreductase (SQR) is the first key enzyme. In order to investigate the mechanism of sulfide tolerance in S. constricta, its SQR (designated as ScSQR), was cloned and characterized. The full-length cDNA of ScSQR was 3698 bp and encoded 443 amino acids. The deduced ScSQR protein contained conserved FAD-binding domains, two cysteine residues, two histidines, and one glutamic acid, which are the essential elements for the catalytic mechanism of SQR. Subcellular localization analysis by the TargetP 1.1 prediction and the Western blot confirmed that ScSQR was only located in the mitochondria. The response of ScSQR in the gill and liver of S. constricta were investigated during sulfide exposure (50, 150, and 300 µM sulfide) for 0, 3, 6, 12, 24, 48, 72, and 96 h by qRT-PCR. Moreover, the time-course expressions of ScSQR protein in the S. constricta gill were detected when exposed to 150 µM sulfide by Western blot. The expression level of ScSQR increased significantly and showed a time-dependent pattern. In addition, under sulfide stress, the expression level of the gill was higher than that of liver. Together, our results suggest that ScSQR may perform important roles in protecting cells from sulfide stress by participating in mitochondrial sulfide detoxification and providing high sulfide tolerance to S. constricta.


Assuntos
Bivalves/embriologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Quinona Redutases/biossíntese , Estresse Fisiológico/efeitos dos fármacos , Sulfetos/farmacologia , Animais , Brânquias/enzimologia , Fígado/enzimologia
4.
Ecotoxicol Environ Saf ; 187: 109841, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31677566

RESUMO

Drought stress is one of the extreme effects of climate change causing large losses in production of crop plants. The risk of recurrent droughts has increased in next decades hence, the development of shot-gun, inexpensive and effective approaches is essential to ensure high yield of crops in drought-prone areas of the world. Exogenous application of nutrients such as potassium (K) has been reported to increase abiotic resistance and improve yield in crops however, knowledge regarding interaction of K with osmoprotectants like chitosan (Ct) still remains elusive. Here, we report the effects of individual or combined K (using K2SO4 as a source) or Ct application on growth, physiological processes and antioxidative defense system of sunflower under drought stress. At first, various doses of K (0, 5, 10, 15, 20, 25 g/l) and Ct (0, 0.1, 0.2, 0.3, 0.4, 0.5 g/l) were foliar applied to evaluate their role in improving plant biomass, water status and total chlorophyll in drought-induced seedlings of sunflower. The optimized K (11.48 g/l) and Ct (0.28 g/l) doses were further tested in second experiment to understand the underlying mechanisms of drought tolerance. Foliar K + Ct spray markedly enhanced the leaf gas exchange characteristics, increased proline, soluble proteins, and free amino acids, upregulated antioxidant defense system and helped to maintain plant water status in sunflower exposed to drought stress. The impact of drought stress was more pronounced at vegetative than reproductive stage and positive effects of combined K and Ct application were related to improved physiological and metabolic processes to improve yield and quality of sunflower under drought stress.


Assuntos
Antioxidantes/metabolismo , Quitosana/farmacologia , Secas , Helianthus/efeitos dos fármacos , Potássio/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Biomassa , Clorofila/metabolismo , Mudança Climática , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Helianthus/crescimento & desenvolvimento , Helianthus/metabolismo , Água/metabolismo
5.
BMC Complement Altern Med ; 19(1): 372, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31847849

RESUMO

BACKGROUND: Vernonia anthelmintica (L.) willd is a traditional urgur herb in China for a long history. Its alcohol extract (AVE) has been proved to promote hair follicle growth in C57BL/6 mice. We conducted this study to investigate the hair-growth effects of AVE in stressed mice and its possible mechanism of action. METHODS: The hair-follicle growth effects of AVE were examined by in vivo and in vitro study. We exposed C57BL/6 male mice to chronic restraint stress to induce murine hair follicle growth inhibition. The effects of AVE were examined by histological analysis, immunofluorescence for Ki67 and cytokeratin 19 immunoreactivity, western blot assay in tyrosinase and related proteins expressions and immunofluorescence for nerve fibers. In organ culture of mouse vibrissae follicles, we used substance P as a catagen-inducing factor of hair follicle growth, and measured the elongation of hair shafts and expression of neurokinin-1 receptor protein by application of AVE. RESULTS: Our results showed that AVE counteract murine hair follicle growth inhibition caused by chronic restraint stress via inducing the conversion of telogen to anagen and inhibiting catagen premature, increasing bulb keratinocytes and bulge stem cells proliferation, promoting melanogenesis, and reducing the numbers of substance P and calcitonin gene-related peptide nerve fibers. Furthermore, AVE also counteracted murine hair follicle growth inhibition caused by substance P in organ culture. CONCLUSION: These results suggest that AVE counteract stress-induced hair follicle growth inhibition in C57BL/6 mice in vivo and in vitro, and may be an effective new candidate for treatment of stress-induced hair loss.


Assuntos
Folículo Piloso/efeitos dos fármacos , Extratos Vegetais/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Vernonia , Animais , Folículo Piloso/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Restrição Física
6.
Br J Anaesth ; 123(6): 777-794, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31668347

RESUMO

BACKGROUND: Dexmedetomidine (DEX) is a highly selective alpha2 adrenoceptor agonist with broad pharmacological effects, including sedation, analgesia, anxiolysis, and sympathetic tone inhibition. Here we report a systematic review and meta-analysis of its effects on stress, inflammation, and immunity in surgical patients during the perioperative period. METHODS: We searched MEDLINE, METSTR, Embase, and Web of Science for clinical studies or trials to analyse the effects of DEX on perioperative stress, inflammation, and immune function. RESULTS: Sixty-seven studies (including randomised controlled trials and eight cohort studies) with 4842 patients were assessed, of which 2454 patients were in DEX groups and 2388 patients were in control (without DEX) groups. DEX infusion during the perioperative period inhibited release of epinephrine, norepinephrine, and cortisol; decreased blood glucose, interleukin (IL)-6, tumour necrosis factor-α, and C-reactive protein; and increased interleukin-10 in surgical patients. In addition, the numbers of natural killer cells, B cells, and CD4+ T cells, and the ratios of CD4+:CD8+ and Th1:Th2 were significantly increased; CD8+ T-cells were decreased in the DEX group when compared with the control group. CONCLUSIONS: DEX, an anaesthesia adjuvant, can attenuate perioperative stress and inflammation, and protect the immune function of surgical patients, all of which may contribute to decreased postoperative complications and improved clinical outcomes.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Dexmedetomidina/farmacologia , Inflamação/tratamento farmacológico , Complicações Intraoperatórias/tratamento farmacológico , Complicações Pós-Operatórias/tratamento farmacológico , Estresse Fisiológico/efeitos dos fármacos , Humanos , Imunidade , Período Pré-Operatório
7.
World J Microbiol Biotechnol ; 35(11): 177, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31696403

RESUMO

Plant biostimulants are defined as materials containing microorganisms or substances whose function when applied to plants or the rhizosphere is to stimulate natural mechanisms to enhance plant growth, nutrient use efficiency, tolerance to abiotic stressors and crop quality, independent of their nutrient content. In agriculture, seaweeds (Macroalgae) have been used in the production of plant biostimulants while microalgae still remain unexploited. Microalgae are single cell microscopic organisms (prokaryotic or eukaryotic) that grow in a range of aquatic habitats, including, wastewaters, pounds, lakes, rivers, oceans, and even humid soils. These photosynthetic microorganisms are widely described as renewable sources of biofuels, bioingredients and biologically active compounds, such as polyunsaturated fatty acids (PUFAs), carotenoids, phycobiliproteins, sterols, vitamins and polysaccharides, which attract considerable interest in both scientific and industrial communities. Microalgae polysaccharides have so far proved to have several important biological activities, making them biomaterials and bioactive products of increasing importance for a wide range of applications. The present review describes microalgae polysaccharides, their biological activities and their possible application in agriculture as a potential sustainable alternative for enhanced crop performance, nutrient uptake and resilience to environmental stress. This review does not only present a comprehensive and systematic study of Microalgae polysaccharides as plant biostimulants but considers the fundamental and innovative principles underlying this technology.


Assuntos
Produtos Agrícolas/efeitos dos fármacos , Microalgas/metabolismo , Desenvolvimento Vegetal/efeitos dos fármacos , Polissacarídeos/metabolismo , Produtos Biológicos/metabolismo , Biotecnologia/métodos , Produtos Agrícolas/metabolismo , Estresse Fisiológico/efeitos dos fármacos
8.
Ecotoxicol Environ Saf ; 186: 109752, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31605954

RESUMO

Tilapias are cultured globally and are rising in acceptance as the most important freshwater aquaculture species. Monitoring of serum biomarkers is a promising tool in aquaculture to screen the health status as they are virtuous indicators of extreme stress and organ dysfunction in fish. The present study examined the serum biomarkers of oxytetracycline (OTC)-dosed Nile tilapia Oreochromis niloticus at 0, 80 and 800 mg/kg biomass/day, i.e., 0X, 1X, and 10X the approved dose (X = 80 mg OTC/kg biomass/day) for 10 consecutive days. The fish biomass and levels of serum glucose, aspartate aminotransferase, alanine aminotransferase, creatinine and C-reactive protein (CRP) were determined at scheduled intervals. A significant dose-dependent reduction in fish biomass during the OTC-dosing (5.84%) and post-OTC dosing (8.16%) periods was observed. All the serum biomarkers of Nile tilapia increased significantly on day 10 OTC-dosing. Though their levels reduced significantly, normalcy was not achieved even after 42 days of cessation of OTC-dosing, except CRP. The CRP reached the normal level on day 25 post-OTC dosing in the 1X group. The results, thus, demonstrated that the oral OTC-dosing influences the physiological state of apparently healthy Nile tilapia in a dose-dependent manner. These changes were, however, reversible upon discontinuation of OTC-dosing. The set of data observed on growth reduction and elevated serum biomarker levels even after 42 days of cessation of OTC-dosing, thus, raises questions on the utility of oral OTC-dosing.


Assuntos
Ração Animal , Antibacterianos/efeitos adversos , Aquicultura/métodos , Ciclídeos/fisiologia , Dieta , Oxitetraciclina/efeitos adversos , Estresse Fisiológico/efeitos dos fármacos , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Biomassa , Glicemia/metabolismo , Proteína C-Reativa/metabolismo , Ciclídeos/sangue , Ciclídeos/crescimento & desenvolvimento , Creatina/sangue , Humanos , Índia , Alimentos Marinhos , Tilápia
9.
Chemosphere ; 236: 124711, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31549668

RESUMO

In recent years, pharmaceuticals have received increasing attentions because of their potential risks to the environment, but researches focusing on their impacts on defense system of living plants are still lacking. As an important class of phytohormones, jasmonates play crucial roles in plant defense system against environmental stress. In order to investigate the effect of pharmaceuticals uptake on endogenous jasmonates, an in vivo solid phase microextraction (SPME) method was established to simultaneously detect and monitor both pharmaceuticals and jasmonates in living plants. The proposed method exhibited wide linear ranges, high sensitivity (limits of detection ranging 0.0043-0.035 ng g-1 for pharmaceuticals and 0.091-0.22 ng g-1 for jasmonates, respectively), and satisfactory reproducibility (relative standard deviation of intrafiber ranging 4.2%-8.6% and interfiber ranging 5.2%-8.2%, respectively). Subsequently, this method was successfully applied to track the concentrations of each pharmaceutical and corresponding jasmonates in living Malabar spinach plants (Basella alba. L) exposed to three common pharmaceuticals (i.e. gemfibrozil, mefenamic acid and tolfenamic acid) over 15 days. In result, all pharmaceuticals appeared to trigger intensive biosynthesis of jasmonic acid (JA) (3.1-9.4 times of control) while reduced the concentration of methyl jasmonate (MeJA) (18.3%-38.1% of control). We inferred that uptake of pharmaceuticals acted as an abiotic stress and stimulated the plant defense response because of the variation of jasmonates. To the best of our knowledge, this is the first study applying SPME to detect and track both pharmaceuticals and phytohormones in living plants, which not only provided a glimpse to the adverse effect of pharmaceuticals on plants as well as the regulation of endogenous jasmonates, but also set a promising template for future in vivo analysis of xenobiotics and plant endogenous substances.


Assuntos
Ciclopentanos/imunologia , Oxilipinas/imunologia , Reguladores de Crescimento de Planta/farmacocinética , Microextração em Fase Sólida/métodos , Spinacia oleracea/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Ciclopentanos/metabolismo , Genfibrozila/farmacologia , Ácido Mefenâmico/farmacologia , Oxilipinas/metabolismo , Preparações Farmacêuticas/análise , Farmacocinética , Reguladores de Crescimento de Planta/análise , Reguladores de Crescimento de Planta/farmacologia , Reprodutibilidade dos Testes , Microextração em Fase Sólida/normas , ortoaminobenzoatos/farmacologia
10.
Genes Dev ; 33(21-22): 1525-1538, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31530651

RESUMO

Cellular homeostasis requires transcriptional outputs to be coordinated, and many events post-transcription initiation can dictate the levels and functions of mature transcripts. To systematically identify regulators of inducible gene expression, we performed high-throughput RNAi screening of the Drosophila Metallothionein A (MtnA) promoter. This revealed that the Integrator complex, which has a well-established role in 3' end processing of small nuclear RNAs (snRNAs), attenuates MtnA transcription during copper stress. Integrator complex subunit 11 (IntS11) endonucleolytically cleaves MtnA transcripts, resulting in premature transcription termination and degradation of the nascent RNAs by the RNA exosome, a complex also identified in the screen. Using RNA-seq, we then identified >400 additional Drosophila protein-coding genes whose expression increases upon Integrator depletion. We focused on a subset of these genes and confirmed that Integrator is bound to their 5' ends and negatively regulates their transcription via IntS11 endonuclease activity. Many noncatalytic Integrator subunits, which are largely dispensable for snRNA processing, also have regulatory roles at these protein-coding genes, possibly by controlling Integrator recruitment or RNA polymerase II dynamics. Altogether, our results suggest that attenuation via Integrator cleavage limits production of many full-length mRNAs, allowing precise control of transcription outputs.


Assuntos
Proteínas de Drosophila/genética , Drosophila/genética , Regulação da Expressão Gênica , Metalotioneína/genética , Regiões Promotoras Genéticas/genética , RNA Mensageiro/metabolismo , Animais , Linhagem Celular , Cobre/toxicidade , Endorribonucleases/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Ligação Proteica , Clivagem do RNA , Estresse Fisiológico/efeitos dos fármacos
11.
BMC Genomics ; 20(1): 712, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31519144

RESUMO

BACKGROUND: Lake Baikal is one of the oldest freshwater lakes and has constituted a stable environment for millions of years, in stark contrast to small, transient bodies of water in its immediate vicinity. A highly diverse endemic endemic amphipod fauna is found in one, but not the other habitat. We ask here whether differences in stress response can explain the immiscibility barrier between Lake Baikal and non-Baikal faunas. To this end, we conducted exposure experiments to increased temperature and the toxic heavy metal cadmium as stressors. RESULTS: Here we obtained high-quality de novo transcriptome assemblies, covering mutiple conditions, of three amphipod species, and compared their transcriptomic stress responses. Two of these species, Eulimnogammarus verrucosus and E. cyaneus, are endemic to Lake Baikal, while the Holarctic Gammarus lacustris is a potential invader. CONCLUSIONS: Both Baikal species possess intact stress response systems and respond to elevated temperature with relatively similar changes in their expression profiles. G. lacustris reacts less strongly to the same stressors, possibly because its transcriptome is already perturbed by acclimation conditions.


Assuntos
Anfípodes/genética , Anfípodes/fisiologia , Lagos , Estresse Fisiológico/genética , Transcriptoma , Anfípodes/efeitos dos fármacos , Animais , Cádmio/toxicidade , Geografia , Resposta ao Choque Térmico/genética , Especificidade da Espécie , Estresse Fisiológico/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos
12.
Ecotoxicol Environ Saf ; 184: 109671, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31539809

RESUMO

Abiotic stress has become one of the most challenging problems for agriculture as the world population keeps increasing dramatically. Crop stress management using manganese (Mn) compounds has been recently employed to reduce the negative effects caused by drought, harsh temperature, and salinity. In response to abiotic stress, an adequate supply of Mn has shown to remediate plant manganese deficiency, induce Mn superoxide dismutase at the transcriptional level to face reactive oxygen species production, and stimulate manganese-dependent proteins to maintain cell integrity. Lately, nanoparticles (NPs) have been explored in agriculture applications. Recent studies have implied that Mn NPs may help plants to overcome abiotic stresses at higher efficiency and lower toxicity, compared to their bulk or ionic counterparts. Although studies have shown that Mn compounds promote crop growth and alleviate abiotic stress, many questions related to Mn-plant networking, their mode of signaling, and the Mn-dependent regulation processes need to be answered.


Assuntos
Produtos Agrícolas/efeitos dos fármacos , Compostos de Manganês/farmacologia , Manganês/farmacologia , Nanopartículas/química , Estresse Fisiológico/efeitos dos fármacos , Produtos Agrícolas/metabolismo , Secas , Manganês/química , Compostos de Manganês/química , Espécies Reativas de Oxigênio/metabolismo , Salinidade , Superóxido Dismutase/metabolismo
13.
Nat Commun ; 10(1): 4020, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488841

RESUMO

Timely perception of adverse environmental changes is critical for survival. Dynamic changes in gases are important cues for plants to sense environmental perturbations, such as submergence. In Arabidopsis thaliana, changes in oxygen and nitric oxide (NO) control the stability of ERFVII transcription factors. ERFVII proteolysis is regulated by the N-degron pathway and mediates adaptation to flooding-induced hypoxia. However, how plants detect and transduce early submergence signals remains elusive. Here we show that plants can rapidly detect submergence through passive ethylene entrapment and use this signal to pre-adapt to impending hypoxia. Ethylene can enhance ERFVII stability prior to hypoxia by increasing the NO-scavenger PHYTOGLOBIN1. This ethylene-mediated NO depletion and consequent ERFVII accumulation pre-adapts plants to survive subsequent hypoxia. Our results reveal the biological link between three gaseous signals for the regulation of flooding survival and identifies key regulatory targets for early stress perception that could be pivotal for developing flood-tolerant crops.


Assuntos
Arabidopsis/metabolismo , Etilenos/metabolismo , Etilenos/farmacologia , Hipóxia , Óxido Nítrico/metabolismo , Estresse Fisiológico/fisiologia , Aclimatação/genética , Aclimatação/fisiologia , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Inundações , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Hemoglobinas/metabolismo , Oxigênio/metabolismo , Proteólise , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Fatores de Transcrição/metabolismo
14.
J Biosci ; 44(4)2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31502577

RESUMO

Crop productivity and yield are adversely affected by abiotic and biotic stresses. Therefore, finding out the genes responsible for stress tolerance is a significant stride towards crop improvement. A gene co-expression network is a powerful tool to detect the most connected genes during heavy metal (HM) stress in plants. The most connected genes may be responsible for HM tolerance by altering the different metabolic pathways during the biotic and abiotic stress. In the same line we have performed the GSE86807 microarray analysis of chickpea during exposure to chromium, cadmium and arsenic and analyzed the data. Common differentially expressed genes (DEGs) during exposure to chromium, cadmium and arsenic were identified and a co-expression network study was carried out. Hub and bottleneck genes were explored on the basis of degree and betweenness centrality, respectively. A gene set enrichment analysis study revealed that genes like haloacid dehydrogenase, cinnamoyl CoA reductase, F-box protein, GDSL esterase lipase, cellulose synthase, beta-glucosidase 13 and isoflavone hydroxylase are significantly enriched and regulate the different pathways like riboflavin metabolism, phenyl propanoid biosynthesis, amino acid biosynthesis, isoflavonoid biosynthesis and indole alkaloid biosynthesis.


Assuntos
Cicer/genética , Metais Pesados/toxicidade , Estresse Fisiológico/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Cicer/efeitos dos fármacos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Redes Reguladoras de Genes/genética
15.
Aquat Toxicol ; 215: 105284, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31479758

RESUMO

Metal pollution in the environment is a serious threat to the biological sustainability of coastal ecosystems. However, our current understanding of the biological effects of metals in these ecosystems is limited. Herein, we investigated the responses of the sea slug Onchidium reevesii to persistent sublethal Cd environmental stress. Dynamic expression was analyzed using various biomarkers. The full-length cDNA of O. reevesii metallothionein (MT) was cloned and consists of 1639 nucleotides encoding a 65 amino acid polypeptide. Phylogenetic analysis showed that Or-MT has conserved Cys residues typical of MTs, including a typical Cys-X-Cys motif, implying that it can function the same as the MT of other shellfish. Expression of Or-MT in response to Cd varied in different tissues, and was highest in gastropod tissues. Thus, regiotemporal expression of MT may be useful for assessing pollution in coastal areas. Cellular immunity (in the hemolymph) and enzyme activity (in the hepatopancreas) were investigated along with hemocyte viability, hemocyte phagocytosis, and superoxide dismutase (SOD) and aspartate aminotransferase (AST) activities. Hemocyte viability was elevated under continuous Cd exposure but hemocyte phagocytosis was decreased. SOD and AST activities in the hepatopancreas fluctuated considerably, and SOD activity was more sensitive. SOD activity was lowest at 4 h and highest at 12 h, while AST activity peaked at 2 h and was lowest at 48 h. Thus, changes in enzyme activity may reveal adaptation to stress. Furthermore, the response patterns of certain enzymes, cellular immunity, and MT expression in O. reevesii could serve as biomarkers of Cd pollution in aquatic environments.


Assuntos
Aspartato Aminotransferases/metabolismo , Biomarcadores/metabolismo , Cádmio/toxicidade , Gastrópodes/metabolismo , Hemócitos/metabolismo , Metalotioneína/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Sobrevivência Celular/efeitos dos fármacos , Exposição Ambiental , Gastrópodes/química , Gastrópodes/efeitos dos fármacos , Gastrópodes/genética , Hemócitos/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Filogenia , Homologia de Sequência de Aminoácidos , Poluentes Químicos da Água/toxicidade
16.
Ecotoxicol Environ Saf ; 184: 109593, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31479760

RESUMO

Leaf vegetables have strong capabilities to take up cadmium (Cd) compared to other vegetable varieties. Until now, the differences in Cd uptake and accumulation by leaf vegetables from different families and genera and the related health risks were unknown. To remedy this, we studied 71 leaf vegetables (multiple genotypes within 17 categories of vegetables) in soil cultivation experiments (3 Cd treatment levels). Results showed that at 2.12 mg kg-1 Cd treatment, the dry weight of only five genotypic varieties from the families Brassicaceae and Asteraceae significantly decreased compared to the control, suggesting their weak Cd tolerances. Vegetables from the Brassicaceae, Asteraceae, Apiaceae, and Convolvulaceae families had stronger Cd absorption capabilities, whereas those from the Liliaceae and Amaranthaceae families had weaker ones. Cluster analysis found that the 17 vegetable categories could be divided into three groups: vegetables with high Cd accumulation capabilities were Lactuca sativa L.var. ramosa Hort. and Lactuca sativa var. longifoliaf. Lam. Vegetables with moderate Cd accumulation capabilities were bok choy, napa cabbage, choy sum, leaf mustard, Lactuca sativa L., Sonchus oleraceus L., celery, coriander, and water spinach. Vegetables with low Cd accumulation capabilities were cabbage, crown daisy, garlic chive, Allium ascalonicum, Gynura cusimbua, and edible amaranth. Estimated daily intake (EDI) and target hazard quotient (THQ) analysis results showed that 100% genotypes of vegetables from the Apiaceae and Convolvulaceae families had health risks; 100% genotypes of Lactuca sativa L., Sonchus oleraceus L., Lactuca sativa L. var. ramosa Hort., and Lactuca sativa var. longifoliaf. Lam from the Asteraceae family carried high risks. Of vegetables in the Brassicaceae family, 42.9% showed risks. Vegetables from the Amaranthaceae and Liliaceae families, Gynura cusimbua and crown daisy from the Asteraceae family, and cabbage from the Brassicaceae family all displayed relatively low risks (all 100%).


Assuntos
Cádmio/metabolismo , Contaminação de Alimentos , Poluentes do Solo/metabolismo , Verduras/metabolismo , Cádmio/análise , Cádmio/toxicidade , Humanos , Folhas de Planta/classificação , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Medição de Risco , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Especificidade da Espécie , Estresse Fisiológico/efeitos dos fármacos , Verduras/classificação , Verduras/efeitos dos fármacos
17.
BMC Mol Cell Biol ; 20(1): 33, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31412778

RESUMO

BACKGROUND: The PINK1:Parkin pathway regulates the autophagic removal of damaged and dysfunctional mitochondria. While the response of this pathway to complete loss of ΔΨm, as caused by high concentrations of mitochondrial ionophores, has been well characterized, it remains unclear how the pathway makes coherent decisions about whether to keep or purge mitochondria in situations where ΔΨm is only partially lost or exhibits fluctuations, as has been observed in response to certain types of cellular stress. RESULTS: To investigate the responses of the PINK1:Parkin pathway to mitochondrial insults of different magnitude and duration, controlled titration of the mitochondrial protonophore, CCCP, was used to manipulate ΔΨm in live cells, and the dynamics of PINK1 and Parkin recruitment was measured by fluorescence microscopy. In contrast to the stable accumulation of PINK1 and Parkin seen at completely depolarized mitochondria, partial depolarization produced a transient pulse of PINK1 stabilization and rapid loss, which was driven by small fluctuations in ΔΨm. As the rate of Parkin dissociation from the mitochondria and phospho-polyubiquitin chain removal was comparatively slow, repetitive pulses of PINK1 were able to drive a slow step-wise accumulation of Parkin and phospho-polyubiquitin leading to deferred mitophagy. CONCLUSION: These data suggest that the PINK1:Parkin mitophagy pathway is able to exhibit distinct dynamic responses to complete and partial mitochondrial depolarization. In this way, the pathway is able to differentiate between irretrievably damaged mitochondria and those showing signs of dysfunction, promoting either rapid or delayed autophagy, respectively.


Assuntos
Mitocôndrias/metabolismo , Proteínas Quinases/metabolismo , Transdução de Sinais , Estresse Fisiológico , Ubiquitina-Proteína Ligases/metabolismo , Autofagia/efeitos dos fármacos , Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , Proteínas de Ciclo Celular/metabolismo , Células HeLa , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas de Membrana Transportadoras/metabolismo , Mitocôndrias/efeitos dos fármacos , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Poliubiquitina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Fatores de Tempo
18.
Ecotoxicol Environ Saf ; 183: 109516, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31394375

RESUMO

The triclosan (TCS) is one of the most commonly detected organic pollutants in the sewage sludge. TCS could induce phytotoxicity in plants. Salicylic acid (SA) is a phenolic compound capable of enhancing plant growth and development. It is well documented that abiotic stress tolerance could be enhanced by exogenous application of SA. However, the regulatory mechanisms for functions of endogenous SA in plants' responses to xenobiotics stress remains unclear. Our results indicated that TCS suppressed plant growth by restricting photosynthesis, decreasing chlorophyll contents and inducing over production of reactive oxygen species (ROS). Interestingly, SA or glutathione (GSH) application could significantly improve plant tolerance to TCS. Moreover, endogenous SA and the expression of a SA binding protein 2 (SABP2) gene were found to be elevated in tobacco under TCS treatment. The overexpression of LcSABP, a SABP2-like gene cloned from the leaves of Lycium chinense, markedly enhanced the SA content in the transgenic plants under TCS stress. The LcSABP-overexpressing plants presented higher photosynthesis rate, chlorophyll content, glutathione reductase (GR) and glutathione-S-transferase (GST) enzymes activities, GSH content and lower O2-•, H2O2 and malondialdehyde (MDA) content in comparison with WT tobacco with TCS treatment. One of the GSH synthesis-related gene, NtGSHS, also showed higher expression level in the transgenic tobacco in comparison with control plants with TCS stress treatment. These results indicated that SABP2 played a positive regulatory role in plant response to TCS stress via increasing the endogenous SA levels. The increased SA content might then increase the GSH content, probably through an increase in GR activity and GSHS gene expression, thus inducing the antioxidant and xenobiotics detoxification systems, which promoted TCS stress tolerance in tobacco plants.


Assuntos
Esterases/genética , Lycium/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico/genética , Tabaco/metabolismo , Triclosan/toxicidade , Antioxidantes/metabolismo , Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Fotossíntese/genética , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética , Espécies Reativas de Oxigênio/metabolismo , Ácido Salicílico/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Tabaco/efeitos dos fármacos , Tabaco/genética
19.
Nat Commun ; 10(1): 3585, 2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31395887

RESUMO

Replication stress, a hallmark of cancerous and pre-cancerous lesions, is linked to structural chromosomal aberrations. Recent studies demonstrated that it could also lead to numerical chromosomal instability (CIN). The mechanism, however, remains elusive. Here, we show that inducing replication stress in non-cancerous cells stabilizes spindle microtubules and favours premature centriole disengagement, causing transient multipolar spindles that lead to lagging chromosomes and micronuclei. Premature centriole disengagement depends on the G2 activity of the Cdk, Plk1 and ATR kinases, implying a DNA-damage induced deregulation of the centrosome cycle. Premature centriole disengagement also occurs spontaneously in some CIN+ cancer cell lines and can be suppressed by attenuating replication stress. Finally, we show that replication stress potentiates the effect of the chemotherapeutic agent taxol, by increasing the incidence of multipolar cell divisions. We postulate that replication stress in cancer cells induces numerical CIN via transient multipolar spindles caused by premature centriole disengagement.


Assuntos
Centríolos/metabolismo , Instabilidade Cromossômica , Segregação de Cromossomos , Neoplasias/genética , Fuso Acromático/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Carcinogênese/genética , Linhagem Celular Tumoral , Centríolos/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/genética , Humanos , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo , Neoplasias/tratamento farmacológico , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Fuso Acromático/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética
20.
Animal ; 13(11): 2727-2735, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31407650

RESUMO

The gut is composed of a single layer of intestinal epithelial cells and plays important roles in the digestion and absorption of nutrients, immune and barrier functions and amino acid metabolism. Weaning stress impairs piglet intestinal epithelium structural and functional integrities, which results in reduced feed intake, growth rates and increased morbidity and mortality. Several measures are needed to maintain swine gut development and growth performance after weaning stress. A large body of evidence indicates that, in weaning piglets, glutamine, a functional amino acid, may improve growth performance and intestinal morphology, reduce oxidative damage, stimulate enterocyte proliferation, modulate cell survival and death and enhance intestinal paracellular permeability. This review focuses on the effects of glutamine on intestinal health in piglets. The aim is to provide evidentiary support for using glutamine as a feed additive to alleviate weaning stress.


Assuntos
Suplementos Nutricionais/análise , Glutamina/farmacologia , Suínos/fisiologia , Aminoácidos/farmacologia , Ração Animal/análise , Animais , Dieta/veterinária , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Permeabilidade/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Suínos/crescimento & desenvolvimento , Desmame
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