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1.
Phytochemistry ; 191: 112911, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34418773

RESUMO

The pleiotropic effects of zinc deficiency on ion homeostasis have already been described in several plants. Tobacco (Nicotiana tabacum) heavy metal ATPases HMA4.1 and HMA4.2 are involved in zinc and cadmium root-to-shoot translocation. In previous research, we have shown that N. tabacum HMA4 RNAi plants and HMA4 double-nonsense mutants exhibit strongly reduced zinc and cadmium levels in leaves as well as stunted growth. In this study, the ionome and transcriptome of these lines were investigated to better characterize the effect of reduced zinc levels and to understand the impaired growth phenotype. We found that, under standard greenhouse fertilization rates, these lines accumulated up to 4- to 6-fold more phosphorus, iron, manganese, and copper than their respective controls. Under field conditions, HMA4 double-mutant plants also exhibited similar accumulation phenotypes, albeit to a lower extent. In both HMA4 RNAi plants and HMA4 mutants, transcription analysis showed a local zinc-deficiency response in leaves as well as an FIT1-mediated iron-deficiency response in roots, likely contributing to iron and manganese uptake at the root level. A phosphate-starvation response involving HHO2 was also observed in HMA4-impaired plant leaves. The high level of phosphorus observed in HMA4-impaired plants is correlated with leaf swelling and necrosis. The upregulation of aquaporin genes is in line with cellular water influx and the observed leaf swelling phenotype. These results highlight the involvement of HMA4 in zinc homeostasis and related regulatory processes that balance the micro- and macroelements in above-ground organs.


Assuntos
Cádmio , Tabaco , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Cádmio/metabolismo , Regulação da Expressão Gênica de Plantas , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Tabaco/metabolismo , Zinco/metabolismo
2.
BMC Plant Biol ; 21(1): 372, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34388971

RESUMO

BACKGROUND: Oilseed rape (B. napus L.) has great potential for phytoremediation of cadmium (Cd)-polluted soils due to its large plant biomass production and strong metal accumulation. Soil properties and the presence of other soluble compounds or ions, cause a heterogeneous distribution of Cd. RESULTS: The aim of our study was to reveal the differential responses of B. napus to different Cd abundances. Herein, we found that high Cd (50 µM) severely inhibited the growth of B. napus, which was not repressed by low Cd (0.50 µM) under hydroponic culture system. ICP-MS assays showed that the Cd2+ concentrations in both shoots and roots under 50 µM Cd were over 10 times higher than those under 0.50 µM Cd. Under low Cd, the concentrations of only shoot Ca2+/Mn2+ and root Mn2+ were obviously changed (both reduced); under high Cd, the concentrations of most cations assayed were significantly altered in both shoots and roots except root Ca2+ and Mg2+. High-throughput transcriptomic profiling revealed a total of 18,021 and 1408 differentially expressed genes under high Cd and low Cd conditions, respectively. The biological categories related to the biosynthesis of plant cell wall components and response to external stimulus were over-accumulated under low Cd, whereas the terms involving photosynthesis, nitrogen transport and response, and cellular metal ion homeostasis were highly enriched under high Cd. Differential expression of the transporters responsible for Cd uptake (NRAMPs), transport (IRTs and ZIPs), sequestration (HMAs, ABCs, and CAXs), and detoxification (MTPs, PCR, MTs, and PCSs), and some other essential nutrient transporters were investigated, and gene co-expression network analysis revealed the core members of these Cd transporters. Some Cd transporter genes, especially NRAMPs and IRTs, showed opposite responsive patterns between high Cd and low Cd conditions. CONCLUSIONS: Our findings would enrich our understanding of the interaction between essential nutrients and Cd, and might also provide suitable gene resources and important implications for the genetic improvement of plant Cd accumulation and resistance through molecular engineering of these core genes under varying Cd abundances in soils.


Assuntos
Brassica napus/genética , Brassica napus/metabolismo , Cádmio/metabolismo , Transporte Biológico , Brassica napus/crescimento & desenvolvimento , Quelantes/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Íons/metabolismo , Solo/química , Tetraploidia , Transcriptoma
3.
Int J Mol Sci ; 22(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34360953

RESUMO

Cadmium (Cd), a heavy metal toxic to humans, easily accumulates in rice grains. Rice with unacceptable Cd content has become a serious food safety problem in many rice production regions due to contaminations by industrialization and inappropriate waste management. The development of rice varieties with low grain Cd content is seen as an economic and long-term solution of this problem. The cation/H+ exchanger (CAX) family has been shown to play important roles in Cd uptake, transport and accumulation in plants. Here, we report the characterization of the rice CAX family. The six rice CAX genes all have homologous genes in Arabidopsis thaliana. Phylogenetic analysis identified two subfamilies with three rice and three Arabidopsis thaliana genes in both of them. All rice CAX genes have trans-member structures. OsCAX1a and OsCAX1c were localized in the vacuolar while OsCAX4 were localized in the plasma membrane in rice cell. The consequences of qRT-PCR analysis showed that all the six genes strongly expressed in the leaves under the different Cd treatments. Their expression in roots increased in a Cd dose-dependent manner. GUS staining assay showed that all the six rice CAX genes strongly expressed in roots, whereas OsCAX1c and OsCAX4 also strongly expressed in rice leaves. The yeast (Saccharomyces cerevisiae) cells expressing OsCAX1a, OsCAX1c and OsCAX4 grew better than those expressing the vector control on SD-Gal medium containing CdCl2. OsCAX1a and OsCAX1c enhanced while OsCAX4 reduced Cd accumulation in yeast. No auto-inhibition was found for all the rice CAX genes. Therefore, OsCAX1a, OsCAX1c and OsCAX4 are likely to involve in Cd uptake and translocation in rice, which need to be further validated.


Assuntos
Antiporters/metabolismo , Cádmio/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Resistência a Medicamentos , Oryza/genética , Proteínas de Plantas/metabolismo , Antiporters/genética , Cádmio/toxicidade , Proteínas de Transporte de Cátions/genética , Transporte de Íons , Oryza/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo
4.
Sci Total Environ ; 796: 149039, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34328900

RESUMO

Cadmium (Cd) is one of the most harmful heavy metals due to its persistence and bioaccumulation through the food chains, posing health risks to human. Oysters can bioaccumulate and tolerate high concentrations of Cd, providing a great model for studying molecular mechanism of Cd detoxification. In a previous study, we identified two CYP genes, CYP17A1-like and CYP2C50, that were potentially involved in Cd detoxification in the Pacific oyster, Crassostrea gigas. In this work, we performed further investigations on their physiological roles in Cd detoxification through RNA interference (RNAi). After injection of double-stranded RNA (dsRNA) into the adductor muscle of oysters followed by Cd exposure for 7 days, we observed that the expressions of CYP17A1-like and CYP2C50 in interference group were significantly suppressed on day 3 compared with control group injected with PBS. Moreover, the mortality rate and Cd content in the CYP17A1-like dsRNA interference group (dsCYP17A1-like) was significantly higher than those of the control on day 3. Furthermore, the activities of antioxidant enzymes, including SOD, CAT, GST, were significantly increased in dsCYP17A1-like group, while were not changed in dsCYP2C50 group. More significant tissue damage was observed in gill and digestive gland of oysters in RNAi group than control group, demonstrating the critical role of CYP17A1-like in Cd detoxification. Dual luciferase reporter assay revealed three core regulatory elements of MTF-1 within promoter region of CYP17A1-like, suggesting the potential transcriptional regulation of CYP17A1-like by MTF-1 in oysters. This work demonstrated a critical role of CYP17A1-like in Cd detoxification in C. gigas and provided a new perspective toward unravelling detoxification mechanisms of bivalves under heavy metal stress.


Assuntos
Crassostrea , Poluentes Químicos da Água , Animais , Cádmio/metabolismo , Cádmio/toxicidade , Crassostrea/genética , Crassostrea/metabolismo , Regulação da Expressão Gênica , Brânquias/metabolismo , Poluentes Químicos da Água/toxicidade
5.
Int J Mol Sci ; 22(14)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34298880

RESUMO

BACKGROUND: The proximal tubule (PT) is the major target of cadmium (Cd2+) nephrotoxicity. Current dogma postulates that Cd2+ complexed to metallothionein (MT) (CdMT) is taken up through receptor-mediated endocytosis (RME) via the PT receptor megalin:cubilin, which is the predominant pathway for reuptake of filtered proteins in the kidney. Nevertheless, there is evidence that the distal parts of the nephron are also sensitive to damage induced by Cd2+. In rodent kidneys, another receptor for protein endocytosis, the 24p3 receptor (24p3R), is exclusively expressed in the apical membranes of distal tubules (DT) and collecting ducts (CD). Cell culture studies have demonstrated that RME and toxicity of CdMT and other (metal ion)-protein complexes in DT and CD cells is mediated by 24p3R. In this study, we evaluated the uptake of labeled CdMT complex through 24p3R after acute kidney injury (AKI) induced by gentamicin (GM) administration that disrupts PT function. Subcutaneous administration of GM at 10 mg/kg/day for seven days did not alter the structural and functional integrity of the kidney's filtration barrier. However, because of PT injury, the concentration of the renal biomarker Kim-1 increased. When CdMT complex coupled to FITC was administered intravenously, both uptake of the CdMT complex and 24p3R expression in DT increased and also colocalized after PT injury induced by GM. Although megalin decreased in PT after GM administration, urinary protein excretion was not changed, which suggests that the increased levels of 24p3R in the distal nephron could be acting as a compensatory mechanism for protein uptake. Altogether, these results suggest that PT damage increases the uptake of the CdMT complex through 24p3R in DT (and possibly CD) and compensate for protein losses associated with AKI.


Assuntos
Cádmio/metabolismo , Endocitose/fisiologia , Túbulos Renais Proximais/metabolismo , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Metalotioneína/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Néfrons/metabolismo
6.
Aquat Toxicol ; 237: 105875, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34098373

RESUMO

The aquatic environment receives a wide variety of contaminants that interact with each other, influencing their mutual toxicity. Therefore, studies of mixtures are needed to fully understand their deleterious effects on aquatic organisms. In the present experiment, we aimed to assess the effects of Cd and Zn mixtures in common carp during a one-week exposure. The used nominal waterborne metal levels were 0.02, 0.05 and 0.10 µM for Cd and 3, 7.5 and 15 µM for Zn. Our results showed on the one hand a fast Cd increase and on the other hand a delayed Zn accumulation. In the mixture scenario an inhibition of Cd accumulation due to Zn was marked in the liver but temporary in the gills. For Zn, the delayed accumulation gives an indication of the efficient homeostasis of this essential metal. Between the different mixtures, a stimulation of Zn accumulation by Cd rather than an inhibition was seen in the highest metal mixtures. However, when compared to an earlier single Zn exposure, a reduced Zn accumulation was observed. Metallothionein gene expression was quickly activated in the analysed tissues suggesting that the organism promptly responded to the stressful situation. Finally, the metal mixture did not alter tissue electrolyte levels.


Assuntos
Carpas , Poluentes Químicos da Água , Animais , Bioacumulação , Cádmio/metabolismo , Cádmio/toxicidade , Carpas/metabolismo , Brânquias/metabolismo , Homeostase , Metalotioneína/metabolismo , Poluentes Químicos da Água/toxicidade , Zinco/metabolismo , Zinco/toxicidade
7.
Methods Mol Biol ; 2326: 267-271, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34097275

RESUMO

Cadmium (Cd) is widespread in the soil, water, and atmosphere, so Cd toxicity to human can happen by breathing in air, drinking water, and eating food from plant grown in Cd-contaminated soil. Cd pollution draws a lot of attention from the scientific community and also regulatory agents and is researched widely by using both plant and animal system. In this protocol, the detection of cadmium (Cd) is described in soil and mature maize (Zea mays) plant with the atomic absorption spectrometer. The Cd uptake, translocation factor, and Cd health risk index are also introduced. The protocol can be modified slightly to measure Cd in different types of plants.


Assuntos
Cádmio/análise , Poluentes do Solo/análise , Solo/química , Zea mays/química , Transporte Biológico , Cádmio/metabolismo , Cádmio/toxicidade , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade , Espectrofotometria Atômica/métodos , Zea mays/metabolismo
8.
Ecotoxicol Environ Saf ; 220: 112392, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34102395

RESUMO

Understanding the molecular mechanisms of cadmium (Cd) tolerance and accumulation in plants is important to address Cd pollution. In the present study, we performed comparative transcriptome analysis to identify the Cd response processes in the roots of two turnip landraces, KTRG-B14 (high-Cd accumulation) and KTRG-B36 (low-Cd accumulation). Two common enhanced processes, glutathione metabolism and antioxidant system, were identified in both landraces. However, some differential antioxidant processes are likely employed by two landraces, namely, several genes encoding peptide methionine sulfoxide reductases and thioredoxins were up-regulated in B14, whereas flavonoid synthesis was potentially induced to fight against oxidative stress in B36. In addition to the commonly upregulated ZINC INDUCED FACILITATOR 1-like gene in two landraces, different metal transporter-encoding genes identified in B14 (DETOXIFICATION 1) and B36 (PLANT CADMIUM RESISTANCE 2-like, probable zinc transporter 10, and ABC transporter C family member 3) were responsible for Cd accumulation and distribution in cells. Several genes that encode extensins were specifically upregulated in B14, which may improve Cd accumulation in cell walls or regulate root development to absorb more Cd. Meanwhile, the induced high-affinity nitrate transporter 2.1-like gene was also likely to contribute to the higher Cd accumulation in B14. However, Cd also caused some toxic symptoms in both landraces. Cd stress might inhibit iron uptake in both landraces whereas many apoenzyme-encoding genes were influenced in B36, which may be attributed to the interaction between Cd and other metal ions. This study provides novel insights into the molecular mechanism of plant root response to Cd at an early stage. The transporters and key enzymes identified in this study are helpful for the molecular-assisted breeding of low- or high-Cd-accumulating plant resources.


Assuntos
Brassica napus/genética , Cádmio/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Proteínas de Plantas/genética , Raízes de Plantas/metabolismo , Poluentes do Solo/metabolismo , Antioxidantes/metabolismo , Biodegradação Ambiental , Brassica napus/metabolismo , Glutationa/metabolismo , Glicoproteínas/genética , Glicoproteínas/metabolismo , Ferro/metabolismo , Estresse Oxidativo , Proteínas de Plantas/metabolismo , Transcriptoma
9.
Planta ; 254(1): 16, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34185181

RESUMO

MAIN CONCLUSION: Key miRNAs including sbi-miR169p/q, sbi-miR171g/j, sbi-miR172a/c/d, sbi-miR172e, sbi-miR319a/b, sbi-miR396a/b, miR408, sbi-miR5384, sbi-miR5565e and nov_23 were identified to function in the regulation of Cd accumulation and tolerance. As an energy plant, sweet sorghum shows great potential in the phytoremediation of Cd-contaminated soils. However, few studies have focused on the regulatory roles of miRNAs and their targets under Cd stress. In this study, comparative analysis of sRNAs, degradome and transcriptomics was conducted in high-Cd accumulation (H18) and low-Cd accumulation (L69) genotypes of sweet sorghum. A total of 38 conserved and 23 novel miRNAs with differential expressions were identified under Cd stress or between H18 and L69, and 114 target genes of 41 miRNAs were validated. Furthermore, 25 miRNA-mRNA pairs exhibited negatively correlated expression profiles and sbi-miR172e together with its target might participate in the distinct Cd tolerance between H18 and L69 as well as sbi-miR172a/c/d. Additionally, two groups of them: miR169p/q-nov_23 and miR408 were focused through the co-expression analysis, which might be involved in Cd uptake and tolerance by regulating their targets associated with transmembrane transportation, cytoskeleton activity, cell wall construction and ROS (reactive oxygen species) homeostasis. Further experiments exhibited that cell wall components of H18 and L69 were different when exposed to cadmium, which might be regulated by miR169p/q, miR171g/j, miR319a/b, miR396a/b, miR5384 and miR5565e through their targets. Through this study, we aim to reveal the potential miRNAs involved in sweet sorghum in response to Cd stress and provide references for developing high-Cd accumulation or high Cd-resistant germplasm of sweet sorghum that can be used in phytoremediation.


Assuntos
MicroRNAs , Sorghum , Biodegradação Ambiental , Cádmio/metabolismo , Cádmio/toxicidade , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , Sorghum/genética , Sorghum/metabolismo , Transcriptoma/genética
10.
Int J Mol Sci ; 22(10)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069632

RESUMO

In tobacco, the efficiency of Zn translocation to shoots depends on Zn/Cd status. Previous studies pointed to the specific contribution of root parts in the regulation of this process, as well as the role of NtZIP4A/B (from the ZIP family; Zrt Irt-like Proteins). Here, to verify this hypothesis, NtZIP4A/B RNAi lines were generated. Then, in plants exposed to combinations of Zn and Cd concentrations in the medium, the consequences of NtZIP4A/B suppression for the translocation of both metals were determined. Furthermore, the apical, middle, and basal root parts were examined for accumulation of both metals, for Zn localization (using Zinpyr-1), and for modifications of the expression pattern of ZIP genes. Our results confirmed the role of NtZIP4A/B in the control of Zn/Cd-status-dependent transfer of both metals to shoots. Furthermore, they indicated that the middle and basal root parts contributed to the regulation of this process by acting as a reservoir for excess Zn and Cd. Expression studies identified several candidate ZIP genes that interact with NtZIP4A/B in the root in regulating Zn and Cd translocation to the shoot, primarily NtZIP1-like in the basal root part and NtZIP2 in the middle one.


Assuntos
Proteínas de Transporte de Cátions/metabolismo , Tabaco/metabolismo , Zinco/metabolismo , Adenosina Trifosfatases/metabolismo , Transporte Biológico/genética , Cádmio/metabolismo , Proteínas de Transporte de Cátions/genética , Regulação da Expressão Gênica de Plantas/genética , Homeostase , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Tabaco/genética
11.
Environ Pollut ; 285: 117301, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34049137

RESUMO

Cadmium (Cd) is a harmful heavy metal that can cause many health problems, while selenium (Se) is an essential nutrient for organisms that can protect them from heavy metal-induced damage. To explore the effects of Se on Cd-induced mitophagy in the liver, forty 3-month-old New Zealand white rabbits (2-2.5 kg), half male and half female, were randomly divided into four groups: the Control group, the Se (0.5 mg/kg body weight (BW)) group, the Cd (1 mg/kg BW) group and the Se+Cd group. After 30 days, the toxicity from Cd in the liver was assessed in terms of the nuclear xenobiotic receptor (NXR) response, oxidative stress and mitophagy. It was found that Cd decreased the activities of CYP450 enzymes and antioxidant enzymes and increased the contents of malondialdehyde (MDA) and hydrogen peroxide (H2O2) and also increased the consumption of reduced glutathione (GSH). Moreover, the mRNA levels of NXRs (CAR, PXR, AHR and Nrf2), some mitochondrial function factors (PGC-1α, Sirt1, Sirt3, Nrf1 and TFAM) and mitochondrial fusion factors (Mfn1, Mfn2 and OPA1) were downregulated, but the mRNA levels of other mitochondrial function factors (VDAC1, Cyt C and PRDX3), mitochondrial fission factors (Fis1 and MFF) and those in the PINK1/Parkin-mediated mitophagy pathway (p62, Bnip3 and LC3) were upregulated under Cd exposure. The protein expression levels of Nrf2, SOD2, PGC-1α, PINK1 and Parkin were consistent with the mRNA expression levels in the Cd group. Se alleviated the changes in the abovementioned factors induced by Cd. In conclusion, the results indicate that Cd can cause oxidative stress in rabbit livers by inhibiting NXRs and the antioxidation response leading to mitophagy, and these harmful changes caused by Cd can be alleviated by Se.


Assuntos
Cádmio , Selênio , Animais , Cádmio/metabolismo , Cádmio/toxicidade , Feminino , Peróxido de Hidrogênio/metabolismo , Fígado/metabolismo , Masculino , Mitofagia , Estresse Oxidativo , Coelhos , Selênio/metabolismo , Xenobióticos/metabolismo
12.
Ecotoxicol Environ Saf ; 220: 112376, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34051661

RESUMO

Previous studies suggest that cadmium (Cd) is one of the causative factors of prostate cancer (PCa), but the effect of chronic Cd exposure on PCa progression remains unclear. Besides, whether long noncoding RNAs (lncRNAs) are involved in the regulation of prolonged exposure to Cd in PCa needs to be elucidated. In the present study, we found that the serum concentration of Cd in PCa patients was positively correlated with the Gleason score and tumor-node-metastasis (TNM) classification. To simulate chronic Cd exposure in PCa, we subjected PC3 and DU145 cells to long-term, low-dose Cd exposure and further examined tumor behavior. Functional studies identified that chronic Cd exposure promoted cell growth and ferroptosis resistance in vitro and in vivo. Furthermore, we found that lncRNA OIP5-AS1 expression was greatly elevated in PC3 and DU145 cells upon chronic Cd exposure. Dysregulation of OIP5-AS1 expression mediated cell growth and Cd-induced ferroptosis. Mechanistically, we demonstrated that OIP5-AS1 served as an endogenous sponge of miR-128-3p to regulate the expression of SLC7A11, a surrogate marker of ferroptosis. Moreover, miR-128-3p decreased cell viability by enhancing ferroptosis. Taken together, our data indicate that lncRNA OIP5-AS1 promotes PCa progression and ferroptosis resistance through miR-128-3p/SLC7A11 signaling.


Assuntos
Sistema y+ de Transporte de Aminoácidos/metabolismo , Cádmio/toxicidade , Poluentes Ambientais/toxicidade , Ferroptose/efeitos dos fármacos , MicroRNAs/metabolismo , Neoplasias da Próstata/metabolismo , RNA Longo não Codificante/metabolismo , Idoso , Idoso de 80 Anos ou mais , Cádmio/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Poluentes Ambientais/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/genética , RNA Longo não Codificante/genética , Transdução de Sinais
13.
Ecotoxicol Environ Saf ; 220: 112370, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34058673

RESUMO

A 6 weeks pot culture experiment was carried out to investigate the stabilization effects of a modified biochar (BCM) on metals in contaminated soil and the uptake of these metals by wheat seedlings. The results showed that the application of BCM significantly increased the soil fertility, the biomass of wheat seedling roots increased by more than 50%, and soil dehydrogenase (DHA) and catalase (CAT) activities increased by 369.23% and 12.61%, respectively. In addition, with the application of BCM, the diethylenetriaminepentaacetic acid extractable (DTPA-extractable) Cd, Pb, Cu and Zn in soil were reduced from 2.34 to 0.38 mg/kg, from 49.27 to 25.65 mg/kg, from 3.55 mg/kg to below the detection limit and from 4.05 to 3.55 mg/kg, respectively. Correspondingly, the uptake of these metals in wheat roots and shoots decreased by 62.43% and 79.83% for Cd, 73.21% and 66.32% for Pb, 57.98% and 68.92% for Cu, and 40.42% and 43.66% for Zn. Furthermore, BCM application decreased the abundance and alpha diversity of soil bacteria and changed the soil bacterial community structure dramatically. Overall, BCM has great potential for the remediation of metal-contaminated soils, but its long-term impact on soil metals and biota need further research.


Assuntos
Bactérias/efeitos dos fármacos , Carvão Vegetal/farmacologia , Metais Pesados/metabolismo , Plântula/metabolismo , Poluentes do Solo/metabolismo , Solo/química , Triticum/efeitos dos fármacos , Disponibilidade Biológica , Biomassa , Cádmio/metabolismo , Poluição Ambiental , Raízes de Plantas/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Microbiologia do Solo , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
14.
Ecotoxicol Environ Saf ; 220: 112315, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34015628

RESUMO

Particulate organic matter (POM) is an effective adsorbent for decreasing the contaminant of cadmium, but little is known about the relevant mechanisms under the effect of plant. In this work, POM were used to study the removal of Cd2+ in the initial concentration range of 0-4.46 mmol L-1 at pH 5.5, and the effect of Artemisia ordosica roots and pH on kinetics and equilibrium of cadmium adsorption on POM and soils were examined. The result indicated that adsorption kinetics fit well with the pseudo-second-order kinetic model, and the equilibrium data for Cd adsorption fit much well to the Langmuir model. The maximum adsorption capacity for POM at equilibrium corresponding to the monolayer coverage reached 0.287 mmol/g for Cd. The amount of Cd adsorbed in the POM and soil increased with the increase of pH from 4 to 8.5. The Artemisia ordosica roots decreased Cd adsorption in POM; instead, the adsorption capacity of soil for Cd was improved under the effect of Artemisia ordosica roots. The Fourier Transform Infrared spectroscopic (FTIR) analysis indicated that the complexation of POM and Cd was mainly through sulfhydryl, hydroxyl and carboxyl groups.


Assuntos
Artemisia/metabolismo , Cádmio/metabolismo , Material Particulado/química , Raízes de Plantas/metabolismo , Poluentes do Solo/química , Poluentes do Solo/metabolismo , Solo/química , Adsorção , Compostos Orgânicos/química
15.
Bull Environ Contam Toxicol ; 106(6): 978-982, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34021770

RESUMO

Juvenile common carp were treated with Cd2+ at a sublethal concentration for Cyprinidae (6.4 mg/L). The expression of N-methyl-D-aspartate receptor subunit genes (NR2A, NR2B) and ATP-binding cassette subfamily C member 1 gene (ABCC1) was compared between treated and untreated fish. In addition, cadmium accumulation in the fish tissues was assessed. NR2A was 18.9-fold upregulated by Cd2+ in the eyes (choroid + retina), which accumulated Cd, and was not upregulated in brain, which didn't accumulate Cd. This may have been caused by the blocking of calcium channels by Cd2+, which has a very similar ionic radius to that of Ca2+. ABCC1 was 2.6-fold upregulated in gills and was not upregulated in liver; both tissues accumulated high levels of Cd. This difference may have been caused by the accumulation of predominantly previously inactivated Cd in liver or by some difference in the mechanisms of self-detoxification from Cd2+ in fish gills and liver.


Assuntos
Carpas , Poluentes Químicos da Água , Animais , Cádmio/metabolismo , Cádmio/toxicidade , Carpas/genética , Brânquias/metabolismo , Fígado/metabolismo , Distribuição Tecidual , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade
16.
Environ Pollut ; 285: 117184, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33962307

RESUMO

The B-type cyclin gene, CycB2, serves as a negative regulator of glandular trichome initiation. Through targeted knockout of NtCycB2 in Nicotiana tabacum cv. K326 using the CRISPR/Cas9 system, we created a variety, HK326, which exhibits significantly increased density and larger glandular heads of long glandular trichomes. Under Cd-stress, HK326 exhibited enhanced Cd tolerance, as demonstrated by a robust root system, strengthened cell membrane stability, and higher photosynthetic parameters. HK326 exhibited enhanced Cd-stress tolerance due to a strong excretion capacity of long glandular trichomes by forming calcium oxalate crystals. Cd mainly accumulated in tobacco shoots rather than remained in roots. Specifically, Cd levels of the HK326 shoot surface were nearly two-fold of those of K326, resulting in less Cd internally in the roots and shoots. Gene expression patterns revealed 11 Cd transporter genes that were upregulated after Cd-stress in shoots, roots, and trichomes. Among them, the NtHMA2 gene encoding heavy metal ATPases and involved in the transport of divalent heavy metal cations was expressed consistently and significantly higher in HK326 than K326, both before and after Cd-stress. NtHMA2 expression was strong in trichomes, moderate in shoots, while weak in roots. The results indicate that NtHMA2 may be involved in Cd excretion from glandular trichomes. Our findings suggest HK326 may be an appropriate candidate plant for Cd-stress tolerance.


Assuntos
Tabaco , Tricomas , Cádmio/metabolismo , Cádmio/toxicidade , Regulação da Expressão Gênica de Plantas , Folhas de Planta/metabolismo , Tabaco/metabolismo , Tricomas/metabolismo
17.
J Plant Physiol ; 261: 153434, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34020275

RESUMO

The commonly used Arabidopsis thaliana natural accessions Columbia (Col-0) and Wassilewskija (Ws) are known to differ in their metal sensitivity, with Col-0 being more sensitive to copper (Cu) and cadmium (Cd) than Ws. As both Cu and Cd are known to affect Cu homeostasis, it was investigated whether this process is part of an accession-specific mechanism underlying their difference in metal sensitivity. As roots are the first contact point during metal exposure, responses were compared between roots of both accessions of hydroponically grown plants exposed to excess Cu or Cd for 24 and 72 h. Root Cu levels increased in both accessions under Cu and Cd exposure. However, under Cu exposure, the downregulation of Cu transporter (COPT) genes in combination with a more pronounced upregulation of metallothionein gene MT2b indicated that Ws plants coped better with the elevated Cu concentrations. The Cd-induced disturbance in Cu homeostasis was more efficiently counteracted in roots of Ws plants than in Col-0 plants. This was indicated by a higher upregulation of the SPL7-mediated pathway, crucial in the regulation of the Cu homeostasis response. In conclusion, maintaining the Cu homeostasis response in roots is key to accession-specific differences in Cu and Cd sensitivity.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Cádmio/metabolismo , Cobre/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Homeostase , Raízes de Plantas/genética , Raízes de Plantas/metabolismo
18.
Life Sci ; 277: 119610, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33989663

RESUMO

AIM: Cadmium (Cd) is a toxic heavy metal that causes severe toxic effects on different tissues including liver and kidney. Therefore the research for alternatives to reduce the damage caused by Cd has substantial importance. This study was performed to examine the possible modulatory effects of carvacrol (CRV) against Cd-induced hepatorenal toxicities and the possible mechanisms underlying these effects. MATERIALS AND METHODS: In the present study, 35 male Wistar rats were randomly divided into 5 groups. The rats were treated with Cd (25 mg/kg) and treated with CRV (25 and 50 mg/kg body weight) for 7 consecutive days. KEY FINDINGS: CRV could modulate Cd-induced elevations of ALT, ALP, AST, urea, creatinine, MDA and enhance antioxidant enzymes' activities such as SOD, CAT, and GPx, and GSH's level. CRV also reversed the changes in levels of inflammatory biomarker and apoptotic genes that include NF-κB, Bcl-3, MAPK-14, iNOS, COX-2, MPO, PGE2, Bax, Bcl-2, P53, Caspase-9, Caspase-6 and Caspase-3 in both tissues. The levels of 8-OHdG in the Cd-induced liver and kidney tissues were modulated after CRV treatment. Furthermore, CRV treatment considerably lowered Cd, Na, Fe, and Zn content while increased K, Ca, Mg and Cu contents in both tissues as compared to the Cd-exposed rats. SIGNIFICANCE: The results of the present study revealed that CRV supplementation could be a promising strategy to protect the liver and kidney tissues against Cd-induced oxidative damage, inflammation and apoptosis.


Assuntos
Intoxicação por Cádmio/tratamento farmacológico , Cimenos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Biomarcadores/metabolismo , Cádmio/metabolismo , Cádmio/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Cimenos/metabolismo , Inflamação/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Terapia de Alvo Molecular/métodos , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Insuficiência Renal/metabolismo
19.
Ecotoxicol Environ Saf ; 219: 112306, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33984557

RESUMO

Cadmium is an environmental pollutant that has extensive deleterious effects on the reproductive system. However, the mechanisms underlying the effects of cadmium on preimplantation embryos are unclear. Here, we used a mouse model to investigate the effects of maternal cadmium (32 mg/l) exposure in drinking water for 2 days on early embryonic development, and studied the mechanisms associated with epigenetic modifications and DNA damage induced by oxidative stress. We observed that maternal cadmium exposure impaired preimplantation embryo development by inducing embryo death, fragmentation, or developmental blockade. After cadmium exposure, the most survived embryos were at the 8-cell stage, which were used for all measurements. Histone acetylation, not methylation, was disturbed by increasing histone deacetylase 1 (HDAC1) levels after cadmium exposure. Cadmium also disrupted DNA methylation of H19; however genomic DNA methylation can be normally reprogrammed in embryos. Furthermore, cadmium increased reactive oxygen species (ROS) levels and DNA damage, and partly inhibited gene expression related to DNA repair. The distribution and activity of mitochondria was increased; therefore, embryos maintain intracellular homeostasis for survival. Collectively, our findings revealed that maternal cadmium exposure impairs preimplantation embryo development by disturbing the epigenetic modification and inducing DNA damage.


Assuntos
Cádmio/toxicidade , Dano ao DNA , Poluentes Ambientais/toxicidade , Epigênese Genética/efeitos dos fármacos , Animais , Blastocisto/metabolismo , Cádmio/metabolismo , Metilação de DNA , Desenvolvimento Embrionário , Feminino , Histona Desacetilase 1 , Camundongos , Gravidez
20.
J Hazard Mater ; 412: 125248, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33951868

RESUMO

Cadmium (Cd) is a typical and widely present toxic heavy metals in environments. Biomineralization of Cd ions could alleviate the toxicity and produce valuable products in certain waste streams containing selenite. However, the impact of the intrinsic Cd(II) efflux system on the biotransformation process remains unrevealed. In this work, the significance of the efflux system on Cd biomineralization was evaluated by constructing engineered Escherichia coli strains, including ΔzntA with suppressed Cd(II) efflux system and pYYDT-zntA with strengthened Cd(II) efflux system. Compared to the wild type (WT), 20% more Cd ions were accumulated in ΔzntA and 17% less were observed in pYYDT-zntA in the presence of selenite as determined by inductively coupled plasma atomic emission spectrometer. Through combination with X-ray absorption fine structure analysis, it was discovered that 50% higher production of CdSxSe1-x quantum dots (QDs) was achieved in the ΔzntA cells than that in the WT cells. Moreover, the ΔzntA cells exhibited the same viability as the WT cells and the pYYDT-zntA cells because accumulated Cd ions were transformed into biocompatible QDs. In addition, the biosynthesized QDs had a uniform particle size (3.82 ± 0.53 nm) and a long fluorescence lifetime (45.6 ns), which could potentially be utilized for bio-imaging. These results not only elucidate the significance of Cd(II) efflux system in the biotransformation of Cd ions and selenite, but also provide a promising way to recover Cd and Se as valuable products in certain waste streams.


Assuntos
Proteínas de Transporte de Cátions , Pontos Quânticos , Biomineralização , Cádmio/metabolismo , Cádmio/toxicidade , Cátions , Escherichia coli/genética , Escherichia coli/metabolismo
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