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1.
Chem Biol Interact ; 312: 108792, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31491373

RESUMO

Cadmium (Cd) is an important toxic chemical due to its increasing levels in the environment and bioaccumulation in humans and animals. The present study was performed to evaluate the effects of long-term exposure to 1, 10, or 100 µg/L Cd in drinking water on the development, reproduction and neurotoxicity of offspring when administered to mice from parental puberty to postnatal 10 weeks in offspring. The development parameters measured in offspring included physical development, reflex ontogeny, body weight and body size. The reproductive indices measured consisted of anogenital distances (AGDs), estrous cycle, sperm quality, specific gene expression in Leydig or Sertoli cells, seminiferous epithelium cycle, sex hormone levels, histological morphology and apoptosis in testis or ovary, and the levels of oxidative stress. The determination of neurotoxicity included learning and memory ability, anxiety, and related serum indicators. In addition, blood lipid level, liver and kidney function were also determined by serum biochemical assays. The results showed that exposure to Cd in the present model had no adverse effects on development, but had some reproductive toxicity and neurotoxicity, including alteration of spermatogenic epithelial staging in testis and inducing anxiety in offspring. Furthermore, the levels of total protein, globulins, total bile acid and direct bilirubin were also significantly altered, especially in female offspring. The present study suggested that long-term exposure to low doses of Cd had adverse effects on the health of the next generation, and some harmful effects showed gender differences in offspring. The present study demonstrated that attention should be paid to Cd pollution in the environment, especially before pregnancy.


Assuntos
Cádmio/toxicidade , Reprodução/efeitos dos fármacos , Animais , Análise Química do Sangue , Feminino , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Ovário/efeitos dos fármacos , Ovário/metabolismo , Ovário/patologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/metabolismo , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia , Esteroide 17-alfa-Hidroxilase/genética , Esteroide 17-alfa-Hidroxilase/metabolismo , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testículo/patologia
2.
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
3.
Ying Yong Sheng Tai Xue Bao ; 30(8): 2767-2774, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418202

RESUMO

To reveal the physiological effects of rice alleviated by cadmium-tolerant Pseudomonas aeruginosa under cadmium stress condition, the influences of bacterial strian on the root vigor and leaf physiological characteristics were analyzed under a set of hydroponic experiments involving adding bacteria suspension, empty carrier, microbial inoculum with 20 µmol·L-1 Cd. Cadmium-free treatment as control. The results showed that the root vigor was significantly inhibited, leaf photosynthetic rate decreased, and the contents of soluble protein, flavonoid and total phenols in rice leaves were reduced, while the contents of malondialdehyde (MDA) and superoxide anion(O2-·) increased significantly under cadmium stress condition. Compared with cadmium treatment, root vigors of rice were increased by 36.1%-42.5% and 49.4%-53.0% respectively in bacteria suspension and microbial inoculum additions, net photosynthetic rates in leaves were increased by 118.5%-147.1% and 137.6%-156.9%, and the contents of soluble protein were increased by 37.0%-49.3% and 37.7%-72.6%, respectively. For the bacteria suspension treatment, the activities of SOD, POD and CAT in leaves were increased by 25.8%-36.6%, 40.9%-55.9%, 24.0%-29.2%, and the activities of SOD, POD and CAT in leaves under microbial inoculum treatment were increased by 36.9%-42.6%, 82.7%-92.6% and 43.3%-52.2%, respectively, with the stimulative effects on antioxidation enzymes in rice leaves being higher than those of bacteria suspension. Compared with cadmium treatment, the contents of MDA and O2-· in rice leaves were reduced by 44.8%-54.7%, 29.4%-41.9% and 9.9%-10.2%, 3.0%-7.1% in microbial inoculum and bacteria suspension treatments, respectively. In contrast, the contents of flavonoids and total phenols were increased by 125.4%-135.7%, 100.8%-119.4% and 139.4%-146.7%, 115.0%-134.7%, respectively. In summary, P. aeruginosa and the microbial inoculum could promote rice seedling growth by improving root vigor and photosynthetic rate, as well as the contents of flavonoids and total phenols, which led to the fact that P. aeruginosa could significantly alleviate the stress of cadmium on rice.


Assuntos
Cádmio/toxicidade , Oryza/fisiologia , Folhas de Planta/fisiologia , Raízes de Plantas/fisiologia , Pseudomonas aeruginosa/fisiologia , Poluentes do Solo/toxicidade , Oryza/microbiologia , Folhas de Planta/microbiologia , Raízes de Plantas/microbiologia , Plântula , Estresse Fisiológico
4.
Ecotoxicol Environ Saf ; 183: 109571, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31446170

RESUMO

The molecular mechanisms of the differences among the Cd tolerance and accumulation of different pak choi cultivars are essential to further breed Cd-safe genotypes pak choi. In our research, via morphological comparison, qRT-PCR and yeast function complementary approaches, we explored the differences of Cd tolerance and capacity for Cd uptake in nine various pak choi varieties. Results showed that higher expressions of BcZIPs involved in Cd uptake in 'Kang Re605' may lead to its higher capacity for Cd accumulation. The lowest expressions of transporter gene in 'Wu Yueman' were consistent with its fewest ability to uptake Cd. Beyond that, the difference of resistance was very great among varieties. Meanwhile, the expressions of the BcGSTUs were differentially induced by Cd exposure in different pak choi varieties, and 'Kang Re605' performed the highest BcGSTUs expression overall. To verify the role of GSTUs played in Cd resistance of pak choi, four BcGSTUs, BcGSTU4, BcGSTU11, BcGSTU12 and BcGSTU22 in a high-Cd accumulation and tolerance variety 'Kang Re605' were cloned, quantitated and transferred to Cd-sensitive yeast mutant strain. And finally found that BcGSTU11 increased the Cd tolerance of yeast, which may associate with a high Cd resistance of 'Kang Re605'. Simultaneously, less BcGSTUs abundance in 'Shang Haiqing' may result in its weak tolerance to Cd. These findings will help us to comprehend the roles of BcZIPs and BcGSTUs in Cd absorption and detoxification as well as promote our understanding of the Cd-resistant and Cd-accumulated mechanisms in pak choi.


Assuntos
Brassica/efeitos dos fármacos , Cádmio/toxicidade , Glutationa Transferase/genética , Proteínas de Plantas/genética , Poluentes do Solo/toxicidade , Transporte Biológico , Brassica/genética , Brassica/metabolismo , Cádmio/metabolismo , Glutationa Transferase/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Plantas/metabolismo , Poluentes do Solo/metabolismo , Fatores de Transcrição , Zinco/metabolismo
5.
J Photochem Photobiol B ; 198: 111580, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31394353

RESUMO

Heavy metal acclimation of bacteria is of particular interest in many aspects. It could add to our understanding of adaptation strategies applied by bacteria, as well as help us in devising ways to use such adaptive bacteria for bioremediation. In this study, we have explored the changes in the DNA of an aquatic Gordonia sp. acclimated to silver, cadmium, and lead. We have measured the changes in the DNA extracted from the acclimated bacteria by using ATR-FTIR coupled with unsupervised and supervised pattern recognition algorithms. Although whole-cell FTIR studies do reveal nucleic acid changes, the special care should be taken when considering marker nucleic acid bands in such spectra, as various other cell or tissue constituents also yield IR bands in the same region. An FTIR study on isolated DNA can be used to avoid this problem. The IR spectral profiles of the DNA molecules revealed significant changes in the backbone and sugar conformations of upon acclimation. We then further analyzed the DNA's global cytosine-methylation patterns of the heavy metal-acclimated bacteria. We aimed to find out whether epigenetic mechanisms operate in bacteria for survival and growth in inhibitory heavy metal concentrations or not. We found hypermethylation in Cd acclimation but hypomethylation for both Pb and Ag in Gordonia sp. Our results imply that changes in the conformational and methylation states of DNA seem to let bacteria to thrive in otherwise inhibitory conditions and mark the involvement of epigenetic modulation in acclimation processes.


Assuntos
Metilação de DNA , DNA Forma Z/química , Gordonia (Bactéria)/química , Metais Pesados/metabolismo , Açúcares/química , Cádmio/química , Cádmio/metabolismo , Cádmio/toxicidade , Análise por Conglomerados , Análise Discriminante , Gordonia (Bactéria)/efeitos dos fármacos , Gordonia (Bactéria)/metabolismo , Chumbo/química , Chumbo/metabolismo , Chumbo/toxicidade , Metais Pesados/química , Metais Pesados/toxicidade , Testes de Sensibilidade Microbiana , Análise de Componente Principal , Prata/química , Prata/metabolismo , Prata/toxicidade , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Aquat Toxicol ; 214: 105264, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31377504

RESUMO

A by-product of mitochondrial substrate oxidation and electron transfer to generate cellular energy (ATP) is reactive oxygen species (ROS). Superoxide anion radical and hydrogen peroxide (H2O2) are the proximal ROS produced by the mitochondria. Because low levels of ROS serve critical regulatory roles in cell physiology while excessive levels or inappropriately localized ROS result in aberrant physiological states, mitochondrial ROS need to be tightly regulated. While it is known that regulation of mitochondrial ROS involves balancing the rates of production and removal, the effects of stressors on these processes remain largely unknown. To illuminate how stressors modulate mitochondrial ROS homeostasis, we investigated the effects of temperature and cadmium (Cd) on H2O2 emission and consumption in rainbow trout liver mitochondria. We show that H2O2 emission rates increase with temperature and Cd exposure. Energizing mitochondria with malate-glutamate or succinate increased the rate of H2O2 emission; however, Cd exposure imposed different patterns of H2O2 emission depending on the concentration and substrate. Specifically, mitochondria respiring on malate-glutamate exhibited a saturable graded concentration-response curve that plateaued at 5 µM while mitochondria respiring on succinate had a biphasic concentration-response curve characterized by a spike in the emission rate at 1 µM Cd followed by gradual diminution at higher Cd concentrations. To explain the observed substrate- and concentration-dependent effects of Cd, we sequestered specific mitochondrial ROS-emitting sites using blockers of electron transfer and then tested the effect of the metal. The results indicate that the biphasic H2O2 emission response imposed by succinate is due to site IIF but is further modified at sites IQ and IIIQo. Moreover, the saturable graded H2O2 emission response in mitochondria energized with malate-glutamate is consistent with effect of Cd on site IF. Additionally, Cd and temperature acted cooperatively to increase mitochondrial H2O2 emission suggesting that increased toxicity of Cd at high temperature may be due to increased oxidative insult. Surprisingly, despite their clear stimulatory effect on H2O2 emission, Cd, temperature and bioenergetic status did not affect the kinetics of mitochondrial H2O2 consumption; the rate constants and half-lives for all the conditions tested were similar. Overall, our study indicates that the production processes of rainbow trout liver mitochondrial H2O2 metabolism are highly responsive to stressors and bioenergetics while the consumption processes are recalcitrant. The latter denotes the presence of a robust H2O2 scavenging system in liver mitochondria that would maintain H2O2 homeostasis in the face of increased production and reduced scavenging capacity.


Assuntos
Cádmio/toxicidade , Metabolismo Energético , Mitocôndrias Hepáticas/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Temperatura Ambiente , Animais , Respiração Celular/efeitos dos fármacos , Transporte de Elétrons , Feminino , Peróxido de Hidrogênio/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias Hepáticas/efeitos dos fármacos , NAD/metabolismo , Oncorhynchus mykiss/fisiologia , Poluentes Químicos da Água/toxicidade
7.
Sci Total Environ ; 687: 768-779, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31412480

RESUMO

Metals are persistent pollutants, able to accumulate in the biota and magnify in trophic web. In the specific case of cadmium contamination, it has been the subject of considerable interest in recent years because of its biological effects and it is one of major pollutant in estuarine areas. Ucides cordatus is considered a mangrove local sentinel crab species in Brazil and there are previous studies reporting crab subpopulations living from pristine to heavily metal impacted areas in São Paulo coast (Southeastern Brazil). Taking into account the background knowledge about these subpopulations, we proposed the hypothesis that crabs from a highly polluted mangrove (Cubatão - CUB) have developed biological tolerance to cadmium compared to animals from an Environmental Protected Area (Jureia - JUR). Aiming to verify this hypothesis, we have investigated total bioaccumulation and subcellular partition of Cd, besides biomarkers' responses during a long-term exposure bioassay (28 days, with weekly sampling) using a supposedly safe Cd concentration (0.0022 mg L-1). Specimens from the pristine area (JUR) accumulated higher total Cd, as such as in its biologically active form in gills. Animals living in the polluted site (CUB) presented higher amounts of Cd in the mainly detoxifying tissue (hepatopancreas), which could be considered a pathway leading to tolerance for this metal. Multivariate analysis indicated that bioaccumulation (active, detoxified and total Cd) is linked to geno-cytotoxic damages. CUB subpopulation was considered more tolerant since it presented proportionally less damage and more capacity to allocate Cd in the main detoxifying forms and tissues.


Assuntos
Braquiúros/fisiologia , Cádmio/toxicidade , Monitoramento Ambiental , Espécies Sentinelas/fisiologia , Poluentes Químicos da Água/toxicidade , Áreas Alagadas , Animais , Brasil , Cádmio/análise , Hepatopâncreas , Poluentes Químicos da Água/análise
8.
Ecotoxicol Environ Saf ; 183: 109485, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31376807

RESUMO

Alternative polyadenylation (APA) is an important way to regulate gene expression at the post-transcriptional level, and is extensively involved in plant stress responses. However, the systematic roles of APA regulation in response to abiotic and biotic stresses in rice at the genome scale remain unknown. To take advantage of available RNA-seq datasets, using a novel tool APAtrap, we identified thousands of genes with significantly differential usage of polyadenylation [poly(A)] sites in response to the abiotic stress (drought, heat shock, and cadmium) and biotic stress [bacterial blight (BB), rice blast, and rice stripe virus (RSV)]. Genes with stress-responsive APA dynamics commonly exhibited higher expression levels when their isoforms with short 3' untranslated region (3' UTR) were more abundant. The stress-responsive APA events were widely involved in crucial stress-responsive genes and pathways: e.g. APA acted as a negative regulator in heat stress tolerance; APA events were involved in DNA repair and cell wall formation under Cd stress; APA regulated chlorophyll metabolism, being associated with the pathogenesis of leaf diseases under RSV and BB challenges. Furthermore, APA events were found to be involved in glutathione metabolism and MAPK signaling pathways, mediating a crosstalk among the abiotic and biotic stress-responsive regulatory networks in rice. Analysis of large-scale datasets revealed that APA may regulate abiotic and biotic stress-responsive processes in rice. Such post-transcriptome diversities contribute to rice adaption to various environmental challenges. Our study would supply useful resource for further molecular assisted breeding of multiple stress-tolerant cultivars for rice.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza/genética , Poliadenilação , Estresse Fisiológico/genética , Cádmio/toxicidade , Secas , Genoma de Planta , Resposta ao Choque Térmico , Oryza/efeitos dos fármacos , Oryza/metabolismo , Oryza/microbiologia , Transcriptoma
9.
Ecotoxicol Environ Saf ; 183: 109517, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31394377

RESUMO

The study aimed to determine the biochar yield of four aquatic plants, the leaching toxicity of copper (Cu) and cadmium (Cd) in the biochar, and the stabilization characteristics of the biochar produced under different pyrolysis conditions (at 350 °C for 1, 2, and 3 h and absence/presence of zeolite powder). The results showed that different plant species required a different pyrolysis duration and the presence or absence of zeolite powder. The stabilization of Cu and Cd was significantly affected by the pyrolysis duration and the external materials for different plant species and different types of admixtures. Pyrolysis temperatures over 350 °C for 1 h without zeolite powder generated stable Cu and Cd in goldfish algae (Ceratophyllum demersum L.), foxtail algae (Myriophyllum verticillatum L.), and penny grass (Hydrocotyle vulgaris). Pyrolysis temperatures over 350 °C for 1 h with zeolite powder made Cu and Cd stable in water celery (Oenanthe javanica (Bl.) DC). The addition of zeolite powder during pyrolysis was possible due to the weight reduction efficiency in plants with Cu and Cd. Furthermore, the surface of the biochar with the zeolite powder showed honeycombs and a spongy porous structure. The duration of the pyrolysis had little effect on the honeycomb pore structure.


Assuntos
Organismos Aquáticos/química , Cádmio/análise , Carvão Vegetal/química , Cobre/análise , Pirólise , Poluentes Químicos da Água/análise , Zeolitas/química , Biomassa , Cádmio/toxicidade , Cobre/toxicidade , Temperatura Alta , Oenanthe/química , Saxifragales/química , Fatores de Tempo , Poluentes Químicos da Água/toxicidade
10.
Georgian Med News ; (291): 93-97, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31418739

RESUMO

The article solves a current task concerning a substantiated use of acetylation phenotype as susceptibility biomarker to unfavourable effect of chemical substances in scientific studies. Objective: to study a combined effect of sodium nitrate and cadmium chloride on the prooxidant-antioxidant balance of the blood, liver and functional state of the central nervous system in young rats with different acetylation type. The experimental studies were performed on immature male rats 1,5-month of age. The experimental animals were divided into two groups according to the amount of general sulfadimine excreted with urine: "rapid" and "slow" acetylators. 2 subgroups were differentiated in every group: I - control animals, II - animals subjected to administration of cadmium chloride and sodium nitrate. Administration of sodium nitrate and cadmium chloride to animals in the doses 1/15 DL50 and 1/150 DL50 respectively during 14 days found that at the young age "slow" acetylation type is susceptibility marker, and the criteria of a harmful effect in them are the following: 25% increase protein peroxide oxidation in the blood plasma, 34% and 30% increase of average molecular peptides and ceruloplasmin respectively, and 6,7 times increase of methemoglobin (hemiglobin) concentration. Nitrate-cadmium intoxication caused inhibition of the integral behavioural activity both in slow and rapid acetylators. Disturbed behavioural activity in young animals with "slow" acetylation type under conditions of subacute effect of sodium nitrate and cadmium chloride is caused mainly by an increased content of liver lipoperoxidation secondary products and less - by the levels of average molecular peptides and ceruloplasmin in the blood plasma, and in "rapid" acetylators - by increased products of oxidation-modification proteins.


Assuntos
Acetilação/efeitos dos fármacos , Cádmio/toxicidade , Nitratos/toxicidade , Animais , Biomarcadores/metabolismo , Intoxicação por Cádmio/metabolismo , Masculino , Fenótipo , Ratos
11.
Sci Total Environ ; 689: 1160-1171, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31466156

RESUMO

Cadmium (Cd) is a widespread environmental pollutant that accumulates in living systems and represents a significant global health hazard. Cd poses a toxicity threat to both human and animal health, including that of birds. Further knowledge of Cd toxicology pathways will allow for a better understanding of Cd-induced nephrotoxicity. To evaluate Cd-induced nephrotoxicity through potential oxidative damage, male chickens were treated with 0 mg/kg, 35 mg/kg or 70 mg/kg CdCl2 in diet for 90 days. Markedly, histopathology indicated renal tubular epithelial cell swelling, renal function CREA content abnormalities, biochemical and morphologic indices indicative of Cd-induced kidney injury. Cd toxicity induced the up-regulation of Nrf2 and downstream target genes that relieve oxidative stress. Meanwhile, Cd disrupted the homeostasis of trace elements and promoted oxidative damage. Cd interfered with mitochondrial unfolded protein response (UPRmt)-related factors (SIRT1, SIRT3, PGC-1α, TFAM, Nrf1, and HTRA2) and disrupted the homeostasis of mitochondrial dynamics (OPA1, MFN1, MFN2, Fis1 and MFF), thereby exacerbating mitochondrial structural damage and mitochondrial dysfunction. In conclusion, our study demonstrated that the nephrotoxicity of Cd exposure results in oxidative stress and mitochondrial dysfunction by activating the Nrf2 signaling pathway and inhibiting UPRmt in the kidneys.


Assuntos
Cádmio/toxicidade , Poluentes Ambientais/toxicidade , Animais , Galinhas , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/fisiologia , Testes de Toxicidade , Resposta a Proteínas não Dobradas/fisiologia
12.
Ecotoxicol Environ Saf ; 182: 109398, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31276887

RESUMO

Cadmium(Cd) is a serious environmental and occupational contaminant that represents a serious health hazard to humans and other animals. Reproductive health problems have been reported in men exposed to Cd. Testicular damage is one of the deleterious effects due to Cd exposure. Cd-induced testicular toxicity is mediated through oxidative stress, inflammation, testosterone inhibition and apoptosis. Thus, the present study was performed to assess the possible protective role of infliximab (IFX), anti-TNFα agent, against Cd-induced testicular damage and spermiotoxicity in rats. The rats were randomly allotted into six experimental groups: control, Cd sulphate treated, Cd sulphate treated with infliximab (5 mg/kg), Cd sulphate with infliximab (7 mg/kg), infliximab alone (5 mg/kg), and infliximab alone (7 mg/kg). The control group received saline. To induce testicular damage, Cd sulphate (1.5 mg/100 gm body weight/day) was dissolved in normal saline and orally administrated for 3 consecutive weeks. The rats in infliximab-treated groups were given a weekly dose of 5 mg/kg/week or 7 mg/kg/week of infliximab intraperitoneally. In the current study Cd exposure reduced sperm count, markers of testicular function, sperm motility as well as gene expression of testicular 3ß-HSD and 17ß-HSD and serum testosterone level. Additionally, it increased testicular oxidative stress, inflammatory and apoptotic markers. The histopathologic studies supported the biochemical findings. Treatment with infliximab significantly attenuated Cd-induced injury verified by the restoration of testicular architecture, enhancement of steroidogenesis, preservation of spermatogenesis, modulation of the inflammatory reaction along with suppression of oxidative stress and apoptosis. It was concluded that infliximab, through its antioxidant, anti-inflammatory and anti-apoptotic effects, represents a potential therapeutic option to protect the testicular tissue from the detrimental effects of Cd.


Assuntos
Antioxidantes/metabolismo , Cádmio/toxicidade , Infliximab/farmacologia , Testículo/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Inflamação , Masculino , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Ratos , Ratos Wistar , Motilidade Espermática/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Testosterona/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
13.
Chemosphere ; 233: 954-965, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31340423

RESUMO

Heavy metals such as cadmium and zinc constitute major pollutants in coastal areas and frequently accumulate in salt marshes. The wetland halophyte plant species Kosteletzkya pentacarpos is a promising species for phytostabilization of contaminated areas. In order to assess the role of the antisenescing phytohormone cytokinin in heavy metal resistance in this species, seedlings were exposed for two weeks to Cd (10 µM), Zn (100 µM) or Cd + Zn (10 µM + 100 µM) in the presence or absence of 50 mM NaCl and half of the plants were sprayed every two days with the cytokinin trans-zeatine riboside (10 µM). Zinc reduced the endogenous cytokinin concentration. Exogenous cytokinin increased plant growth, stomatal conductance, net photosynthesis and total ascorbate and reduced oxidative stress estimated by malondialdehyde in Zn-treated plants maintained in the absence of NaCl. Heavy metal induced an increase in the senescing hormone ethylene which was reduced by cytokinin treatment. Plants exposed to the mixed treatment (Cd + Zn) exhibited a specific hormonal status in relation to accumulation of abscisic acid and depletion of salicylic acid. Non-protein thiols (glutathione and phytochelatins) accumulated in response to Cd and Cd + Zn. It is concluded that toxic doses of Cd and Zn have different impacts on the plant behavior and that the simultaneous presence of the two elements induces a specific physiological constraint at the plant level. Salinity helps the plant to cope with heavy metal toxicities and the plant hormone cytokinin assumes key function in Zn resistance but its efficiency is lower in the presence of NaCl.


Assuntos
Cádmio/toxicidade , Citocininas/metabolismo , Hibiscus/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Cloreto de Sódio/farmacologia , Zinco/toxicidade , Ácido Abscísico/análise , Glutationa/metabolismo , Hibiscus/crescimento & desenvolvimento , Fotossíntese/efeitos dos fármacos , Fitoquelatinas/metabolismo , Desenvolvimento Vegetal/efeitos dos fármacos , Ácido Salicílico/análise , Salinidade , Plântula/fisiologia , Poluentes Químicos da Água/toxicidade , Áreas Alagadas
14.
Ecotoxicol Environ Saf ; 182: 109431, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31301593

RESUMO

The objective of this study was to examine the response of soil archaeal communities to saline stress in different types of Cd-contaminated soils from the North China Plain. Increased soil salinity by addition of 0.5% sodium salts (NaCl: Na2SO4: NaHCO3: Na2CO3 = 1:9:9:1) increased available Cd concentration, resulting in decreased ratios of Cd2+/CdT and CdSO4/CdT and increased ratios of CdCln2-n/CdT in soil solution. Soil saline stress decreased archaeal abundance and diversity and changed major soil archaeal taxa. For example, increased saline stress enriched taxa in the archaeal phyla Thaumarchaeota and Euryarchaeota, and these enriched tolerant taxa had much stronger correlations with soil properties, such as soil pH, EC or Na+. In addition, some microbes with low abundances like Bathyarchaeia (no rank) and Candidatus Nitrosotenuis were found to closely correlate with soil pH, EC, Na+, and Cl-, indicating they might play disproportionate roles in regulating ecological functions in stressed habitats. These results suggest that saline stress modified the effect of Cd toxicity on soil archaeal communities in different types of Cd-contaminated soils.


Assuntos
Archaea/efeitos dos fármacos , Cádmio/toxicidade , Estresse Salino , Microbiologia do Solo , Poluentes do Solo/toxicidade , Archaea/fisiologia , Cádmio/química , China , Solução Salina , Salinidade , Cloreto de Sódio , Solo/química , Poluentes do Solo/química
15.
Biomed Environ Sci ; 32(7): 508-519, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31331435

RESUMO

OBJECTIVE: The aim of this study is to investigate the effects of oral cadmium (Cd) ingestion on the pulmonary immune response. METHODS: Determination of Cd content in lungs and histopathological evaluation of the tissue was performed in rats following 30-day oral Cd administration (5 and 50 mg/L). Antioxidant enzyme defense (superoxide dismutase and catalase), cell infiltration, and production of tumor necrosis factor (TNF) and interferon (IFN)-γ, as well as the activity of myeloperoxidase (MPO), nitric oxide (NO), and various cytokines [interleukin (IL)-1ß, IL-6, IL-10, and IL-17] were investigated. RESULTS: Cd caused tissue damage and cell infiltration in the lungs, and this damage was more pronounced at higher doses. Cd deposition resulted in lung inflammation characterized by a dose-dependent IL-1ß increase in lung homogenates, increased TNF levels at both doses, and IL-6 stimulation at low doses with inhibition observed at higher doses. Cd exerted differential effects on lung leukocytes isolated by enzyme digestion, and these effects were characterized by a lack of change in the production of reactive oxygen and nitrogen species, an inhibition of IL-1ß and TNF, and stimulation of MPO and IFN-γ. The higher capacity of Cd-exposed lung cells to respond to the opportunistic pathogen Staphylococcus epidermidis was demonstrated in vitro. CONCLUSION: The potential of ingested Cd to exert both proinflammatory and immunosuppressive effects on pulmonary tissue inflammation and immune reactivity highlights the complex immunomodulatory actions of this metal.


Assuntos
Cádmio/toxicidade , Pulmão/efeitos dos fármacos , Administração Oral , Animais , Cádmio/administração & dosagem , Leucócitos/metabolismo , Pulmão/imunologia , Pulmão/patologia , Masculino , Ratos , Staphylococcus epidermidis , Testes de Toxicidade Subcrônica
16.
Environ Pollut ; 252(Pt B): 1791-1800, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31299508

RESUMO

Phytochelatins (PCs) play a vital role in the tolerance and enrichment of cadmium (Cd) in higher plants by chelating with Cd2+. The aim of this study was to perform a full-scale metabolomics analysis of metabolic responses highly correlated with PCs generation. These metabolites and metabolic pathways were expected to promote PCs generation and further optimize Cd absorption in plants. In the current study, Amaranthus hypochondriacus, a potential species for phytoremediation, was first adopted to investigate physiological responses to Cd stress via LCMS/MS-based metabolomics and the HPLC based determination of thiol compounds. The results showed that the leaves of A. hypochondriacus under high Cd stress accumulated 40 times the amount of Cd compared to the leaves of the plants not under Cd stress and had an increased content of three types of PCs. Metabolomics qualitatively identified 12084 substances in total, among which 41 were significantly different metabolites (SDMs) between the two groups and involved in 7 metabolic pathways. Among the SDMs, 12 metabolites were highly linearly correlated with PCs involved in three pathways (Val, Leu and Ile biosynthesis; Ala, Asp and Glu metabolism; and Arg and Pro metabolism). These results provide an innovative method to promote PCs synthesis for the restoration of Cd-contaminated-soil.


Assuntos
Amaranthus/metabolismo , Cádmio/metabolismo , Redes e Vias Metabólicas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fitoquelatinas/biossíntese , Poluentes do Solo/metabolismo , Amaranthus/efeitos dos fármacos , Biodegradação Ambiental , Cádmio/toxicidade , Metabolômica , Modelos Teóricos , Solo/química , Poluentes do Solo/toxicidade
17.
Environ Pollut ; 252(Pt B): 1609-1621, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31284203

RESUMO

Land degradation by salinization and sodification changes soil function, destroys soil health, and promotes bioaccumulation of heavy metals in plants, but little is known about their fundamental mechanisms in shaping microbial communities and regulating microbial interactions. In this study, we explored the impact of saline-alkaline (SA) stress on soil bacterial and fungal community structures in different Cd-contaminated soils of Dezhou, Baoding, Xinxiang, Beijing and Shenyang cities from the North China Plain, China. Increased soil salinity and alkalinity enhanced Cd availability, indicated by significant increases in available Cd2+ in soil solution of 34.1%-49.7%, soil extractable Cd of 32.0-51.6% and wheat root Cd concentration of 24.5%-40.2%, as well as decreased activities of antioxidative enzymes of wheat root when compared with CK (no extra neutral or alkaline salts added). Soil bacteria were more active in response to the SA stress than fungi, as the significant structural reorganization of soil bacterial microbiota rather than fungal microbiota between SA and CK treatments was illustrated by principal component analysis. Adding neutral and alkaline salts enriched oligotrophic and haloalkaliphilic taxa in the Sphingobacteriaceae, Cellvibrionaceae, and Caulobacteraceae bacterial families, but decreased some Acidobacteria such as subgroup 6_norank, which was a sensitive biomarker that responded only to Cd contamination in CK-treated soils. Conversely, fungi were more sensitive to soil differences than bacteria: the composition of the fungal community was significantly different among different soil types. Phylogenetic molecular ecological network (pMEN) analysis further indicated that the microbial community structure and network interactions were altered to strengthen the adaptability of microorganisms to SA stress; the changes in structure and network interactions were proposed to contribute to competitive interactions. Most of the keystone genera identified in SA-treated soils, such as Blastococcus, Gemmatimonas, RB41, or Candida, had relatively low abundances (<1%), indicating their disproportionate ecological roles in triggering resistance or tolerance to SA stress and Cd toxicity.


Assuntos
Álcalis/toxicidade , Cádmio/toxicidade , Interações Microbianas/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Microbiologia do Solo , Poluentes do Solo/toxicidade , Bactérias/efeitos dos fármacos , China , Cidades , Fungos/efeitos dos fármacos , Filogenia , Salinidade
18.
Ecotoxicol Environ Saf ; 182: 109459, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31344591

RESUMO

The utilization of forages grown on metal-contaminated soil can increase the risk of heavy metals entering the food chain and affecting human health because of elevated toxic metal concentrations. Meanwhile, hydrogen sulfide (H2S) and nitric oxide (NO) as signaling molecules are known to promote plant growth in metal-contaminated soils. However, the regulatory mechanisms of such molecules in plant physiology and soil biochemistry have not been well-documented. Hence, we investigate the role of the exogenous application of H2S and NO on alfalfa growth in lead/cadmium (Pb/Cd)-contaminated soil. Our results indicate that the signaling molecules increase the alfalfa chlorophyll and biomass content and improve alfalfa growth. Further, H2S and NO reduce the translocation and bioconcentration factors of Pb and Cd, potentially reducing the risk of heavy metals entering the food chain. These signaling molecules reduce metal-induced oxidative damage to alfalfa by mitigating reactive oxygen species accumulation and increasing antioxidant enzyme activities. Their exogenous application increases soil enzymatic activities, particularly of catalase and polyphenol oxidase, without significantly changing the composition and structure of rhizosphere bacterial communities. Interestingly, H2S addition enriches the abundance of plant-growth-promoting rhizobacteria in soil, including Nocardioides, Rhizobium, and Glycomyces. H2S is more effective than NO in improving alfalfa growth and reducing heavy-metal contamination of the food chain. These results provide new insights into the exogenous application of signaling molecules in alleviating metal-induced phytotoxicity, including an efficient strategy for the safe use of forages.


Assuntos
Cádmio/análise , Sulfeto de Hidrogênio/farmacologia , Chumbo/análise , Medicago sativa/efeitos dos fármacos , Óxido Nítrico/farmacologia , Poluentes do Solo/análise , Irrigação Agrícola , Biomassa , Cádmio/toxicidade , Fumigação , Sulfeto de Hidrogênio/administração & dosagem , Chumbo/toxicidade , Medicago sativa/química , Medicago sativa/crescimento & desenvolvimento , Microbiota/efeitos dos fármacos , Óxido Nítrico/administração & dosagem , Poluentes do Solo/toxicidade
19.
Plant Physiol Biochem ; 142: 193-201, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31301530

RESUMO

Toxic impact of cadmium (Cd) on plants is well known which affects their productivity. To mitigate toxic impact of metals such as Cd, exogenous application of phytohormones like indole acetic acid (IAA) has been well recognized in the recent past. But, mechanisms related to the IAA-mediated mitigation of metal toxicity remain elusive. Therefore, in this study, effect of IAA on growth and photosynthetic attributes, nitric oxide, cell viability, reactive oxygen species (ROS) and ascorbate-glutathione cycle (AsA-GSH cycle) was investigated in tomato roots exposed to Cd stress. Cd declined growth and photosynthetic attributes which were accompanied by the excess accumulation of Cd and decreased level of nitric oxide (NO). Among photosynthetic attributes, quantum yield parameters were more sensitive to Cd and these results were in parallel of photosynthetic pigments. However, exogenously applied IAA together with Cd significantly improved level of NO, growth and photosynthetic attributes together with reduced accumulation of Cd. Cd enhanced level of superoxide radical and hydrogen peroxide leading to severe damage to lipids and membranes as indicated by increased level of lipid peroxidation and electrolyte leakage which collectively reduced cell viability of roots. Moreover, components of the AsA-GSH cycle i.e. enzymes (ascorbate peroxidase, monodehydroascorbate reducatse, dehydroascorbate reducatse and glutathione reductase) and metabolites (ascorbate and glutathione) were declined by the Cd. However, addition of IAA with Cd had up-regulated components of the AsA-GSH cycle. Interestingly, application of 2,4,6-triiodobenzoic acid (TIBA, a polar auxin transport inhibitor) diminished growth attributes and its combination with Cd worsened its toxicity and these events were in parallel with decline in NO content and enhancement in Cd accumulation. The results also showed that IAA was also able in mitigating Cd toxicity in tomato roots even in the presence of TIBA. Overall results show the essentiality of IAA in mitigating Cd stress in tomato roots through NO that up-regulates components of the AsA-GSH cycle for balancing ROS and their associated damages and hence much improved growth and photosynthetic attributes were noticed.


Assuntos
Cádmio/toxicidade , Depuradores de Radicais Livres/metabolismo , Ácidos Indolacéticos/metabolismo , Lycopersicon esculentum/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Ácido Ascórbico/metabolismo , Glutationa/metabolismo , Lycopersicon esculentum/metabolismo , Óxido Nítrico/metabolismo , Fotossíntese/efeitos dos fármacos , Raízes de Plantas/metabolismo
20.
Aquat Toxicol ; 214: 105259, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31352075

RESUMO

The potential of using gene expression signature as a biomarker of toxicants exposure was explored in the microalga Chlamydomonas reinhardtii exposed 2 h to mercury (Hg) as inorganic mercury (IHg) and methyl mercury (MeHg) in presence of copper (Cu) and Suwannee River Humic Acid (SRHA). Total cellular Hg (THg = IHg + MeHg) decreased in presence of SRHA for 0.7 nM IHg and 0.4 nM MeHg, but increased for 70 nM IHg exposure. In mixtures of IHg + MeHg and (IHg or MeHg) + Cu, SRHA decreased THg uptake, except for 0.7 nM IHg + 0.4 nM MeHg which was unchanged (p-value>0.05). In the absence of SRHA, 0.5 µM Cu strongly decreased intracellular THg concentration for 70 nM IHg, while it had no effect for 0.7 nM IHg and 0.4 nM MeHg. The expression of single transcripts was not correlated with measured THg uptake, but a subset of 60 transcripts showed signatures specific to the exposed metal(s) and was congruent with exposure concentration. Notably, the range of fold change values of this subset correlated with THg bioaccumulation with a two-slope pattern in line with [THg]intra/[THg]med ratios. Gene expression signature seems a promising approach to complement chemical analyses to assess bioavailability of toxicants in presence of other metals and organic matter.


Assuntos
Chlamydomonas reinhardtii/genética , Exposição Ambiental , Perfilação da Expressão Gênica , Mercúrio/toxicidade , Compostos de Metilmercúrio/toxicidade , Animais , Disponibilidade Biológica , Cádmio/toxicidade , Chlamydomonas reinhardtii/efeitos dos fármacos , Chlamydomonas reinhardtii/metabolismo , Feminino , Substâncias Húmicas/análise , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , NAD/metabolismo , Oncorhynchus mykiss/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Temperatura Ambiente , Poluentes Químicos da Água/toxicidade
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