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1.
World J Microbiol Biotechnol ; 39(3): 84, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36693977

RESUMO

The coexistence of heavy metals (HMs) and petroleum hydrocarbons (PHs) exacerbates ecotoxicity and impair the drivers of eco-functionalities that stimulate essential nutrients for the productivity of the impacted environment. Profiling the bacteria that stem the ecological impact via HMs sequestration and PHs catabolism with nitrogen fixation is imperative to bioremediation of the polluted sites. The sediment of site that was consistently contaminated with industrial wastewaters was analysed for ecological toxicants and the bacterial strains that combined HMs resistance with PHs catabolism in a nitrogen-limiting system were isolated from the sediment and characterized. The geochemistry of the samples revealed the co-occurrence of the above-benchmark concentrations of HMs with the derivatives of hydrocarbons. Notwithstanding, nickel and mercury (with 5% each of the total metal concentrations in the polluted site) exhibited probable effect concentrations on the biota and thus hazardous to the ecosystem. Approx. 31% of the bacterial community, comprising unclassified Planococcaceae, unclassified Bradyrhizobiaceae, Rhodococcus, and Bacillus species, resisted 160 µmol Hg2+ in the nitrogen-limiting system within 24 h post-inoculation. The bacterial strains adopt volatilization, and sometimes in combination with adsorption/bioaccumulation strategies to sequester Hg2+ toxicity while utilizing PHs as sources of carbon and energy. Efficient metabolism of petroleum biomarkers (> 87%) and Hg2+ sequestration (≥ 75% of 40 µmol Hg2+) displayed by the selected bacterial strains portend the potential applicability of the bacilli for biotechnological restoration of the polluted site.


Assuntos
Bacillus , Mercúrio , Metais Pesados , Petróleo , Petróleo/metabolismo , Ecossistema , Metais Pesados/metabolismo , Bactérias/genética , Bactérias/metabolismo , Biodegradação Ambiental , Hidrocarbonetos/metabolismo , Bacillus/metabolismo
2.
Sci Rep ; 13(1): 1292, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36690679

RESUMO

Human metallothionein-2A (MT2A) protein participates in metal homeostasis, detoxification, oxidative stress reduction, and immune defense. It decreases heavy metal ions and reactive oxygen species (ROS) during injury of cells and tissues. The single nucleotide polymorphisms at the MT2A gene have been associated in various human diseases including cancer. The current study aimed to elucidate associations between MT2A genotypes with the clinical, biochemical, and molecular characteristics that potentially related to lowered MT2A ex-pression. One hundred and forty-one healthy Taiwanese subjects were enrolled from Changhua Show-Chwan Memorial Hospital. Clinical, biochemical and molecular characteristics including the frequent minor allele SNPs, rs28366003 and rs10636, within the MT2A gene were determined. The genotype distribution of MT2A rs10636 fits the Hardy-Weinberg equilibrium. The significant associations with gradually decline of mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) were identified with MT2A rs10636 and rs28366003 using analysis of variance (ANOVA) with Tukey's analysis as a post hoc test. We further validated the correlations between the expressions of genes in erythropoiesis, cholesterol synthesis, platelet synthesis, insulin with MT2A using the web-based Gene Expression Profiling Interactive Analysis (GEPIA) databases. The results revealed that hypoxia-inducible factor 1α (HIF-1α), erythropoietin (EPO), lipoprotein lipase (LPL), and lecithin-cholesterol acyltransferase (LCAT) mRNA ex-pression are significantly correlated with MT2A mRNA expression. In conclusion, these results suggested that genetic variations of MT2A rs10636 and rs28366003 might be an important risk factor for erythropoiesis in the Taiwanese general population.


Assuntos
Índices de Eritrócitos , Eritropoese , Metalotioneína , Humanos , Alelos , Genótipo , Metalotioneína/genética , Metais Pesados/metabolismo , Polimorfismo de Nucleotídeo Único , Taiwan
3.
Plant Physiol Biochem ; 195: 247-255, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36645929

RESUMO

Heavy metal pollution in the soil is a serious threat to crop growth and human health. Metallothionein (MT) is a low molecular weight protein that is rich in cysteine, which can effectively alleviate the toxicity of heavy metals in plants. In this study, a novel metallothionein encoding gene, NtMT2F, was cloned from the Cd-hyperaccumulator tobacco and heterologously expressed in E. coli and A. thaliana to verify its biological function. Recombinant E. coli incubated with NtMT2F effectively resisted heavy metal stress, particularly Cd. The recombinant strain grew significantly faster and had a higher content of Cd than the control. Mutations in the C-terminal Cys residues of NtMT2F significantly reduced its ability to chelate heavy metals. The overexpression of NtMT2F significantly enhanced resistance to Cd toxicity in transgenic A. thaliana. The germination rate, root length, and fresh weight of transgenic plants under Cd stress were higher than those of the wild type (WT). The contents of hydrogen peroxide (H2O2) and malondialdehyde (MDA) were lower than those of the WT. In addition, the activities of anti-peroxidase enzymes including glutathione reductase (GR), catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD), were significantly increased in the transgenic plants. The results of this study indicate that NtMT2F significantly improved the tolerance of microorganisms and plants to Cd and could be an important candidate protein for phytoremediation.


Assuntos
Arabidopsis , Metais Pesados , Humanos , Arabidopsis/genética , Arabidopsis/metabolismo , Cádmio/toxicidade , Cádmio/metabolismo , Tabaco/genética , Tabaco/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Metalotioneína/genética , Metalotioneína/metabolismo , Peróxido de Hidrogênio/metabolismo , Metais Pesados/toxicidade , Metais Pesados/metabolismo , Plantas Geneticamente Modificadas/metabolismo
4.
Int J Biol Macromol ; 229: 388-400, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36592848

RESUMO

In this study, we successfully isolated 11 species of cadmium-tolerant bacterium from Pu-erh rhizosphere soil, of which Staphylococcus equorum PU1 showed the highest cadmium tolerance, with a minimum inhibitory concentration (MIC) value of 500 mg/L. The cadmium removal efficiency of PU1 in 400 mg/L cadmium medium reached 58.7 %. Based on the Nanopore PromethION and Illumina NovaSeq platforms, we successfully obtained the complete PU1 genome with a size of 2,705,540 bp, which encoded 2729 genes. We further detected 82 and 44 indel mutations in the PU1 genome compared with the KS1039 and KM1031 genomes from the database. Transcriptional analysis showed that the expression of 11 genes in PU1 increased with increasing cadmium concentrations (from 0 to 200, then to 400 mg/L), which encoded cadmium resistance, cadmium transport, and mercury resistance genes. In addition, some genes showed differential expression patterns with changes in cadmium concentration, including quinone oxidoreductase-like protein, ferrous iron transport protein, and flavohemoprotein. Gene Ontology (GO) functions, including oxidation reduction process and oxidoreductase activity functions, and KEGG pathways, including glycolysis/gluconeogenesis and biosynthesis of secondary metals, were also considered closely related to the extreme cadmium tolerance of PU1. This study provides novel insight into the cadmium tolerance mechanism of bacteria.


Assuntos
Metais Pesados , Poluentes do Solo , Cádmio/metabolismo , Transcriptoma , Adsorção , Metais Pesados/metabolismo , Genômica , Bactérias/metabolismo , Oxirredutases/metabolismo , Biodegradação Ambiental , Poluentes do Solo/metabolismo
5.
J Insect Physiol ; 144: 104469, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36525990

RESUMO

The increased human activities and the worldwide population growth are constantly increasing the production of solid wastes. Over the years, waste management has thus become a prominent issue for several companies and municipalities, and several engineering techniques have been developed over the years in order to convert wastes into other solid materials or fuels. Yet, several techniques are important contributors to environmental pollution, and biological-based solutions have thus become progressively very popular. In particular, insect-based conversion of organic wastes represent eco-friendly tools, and the growth and development of insect species such as the black soldier fly have been tested and improved for a large diversity of organic wastes. However, organic wastes, including food wastes, may contain several pollutants such as heavy metals and catechol which could affect the bioconversion efficiency by incurring physiological costs that would be undetectable at the organismal level, i.e. have null to little effects on the life cycle of Hermetia illucens. In this context, assessments of antioxidant capacities can provide a rapid and low-cost evaluation of the capability of insects to handle exposure to heavy metals and catechol. Here, we aimed at measuring the physiological responses of the black soldier fly H. illucens grown on food wastes (kitchen, fruit or vegetable wastes) contaminated by cadmium, iron, lead or catechol. Biomarkers of oxidative stress (concentrations of hydrogen peroxide and protein carbonyls), non-enzymatic total antioxidant capacity (ascorbic acid amounts) and activity of enzymatic antioxidants (activities of superoxide dismutase and polyphenoloxidase) were measured from the gut of the larvae. We found no evidence of deleterious impacts of food waste contamination by catechol or heavy metals on H. illucens. In most experimental treatments, the array of physiological endpoints we measured for evaluating the degree of oxidative stress experienced by the larvae remained similar to controls. Possible physiological effects were reported for cadmium and catechol only, which tended to increase the oxidation of proteins and hydrogen peroxide in the larvae. Finally, our results suggested that the nature of the food waste could equally affect the physiological responses of the insect.


Assuntos
Dípteros , Metais Pesados , Eliminação de Resíduos , Humanos , Animais , Cádmio/metabolismo , Antioxidantes/metabolismo , Peróxido de Hidrogênio/metabolismo , Larva , Metais Pesados/metabolismo , Frutas , Catecóis/metabolismo
6.
Environ Pollut ; 316(Pt 1): 120543, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36341832

RESUMO

The combined pollution of antibiotics and heavy metals has attracted a worldwide attention in the recent years. 4-epianhydrotetracycline (EATC) is the major degradation product of tetracycline (TC), which has been detected frequently in environment and its concentration is even higher than TC under some circumstances. Cadmium (Cd) is a common heavy metal contaminant and has highly toxic to organisms, plants and humans even at low doses. In the present study, zebrafish (Danio rerio) embryo toxicity test was performed to investigate the single and combined effects of EATC and Cd on aquatic organisms. Exposure to EATC and Cd at environmentally relevant concentrations had a series of hazardous impacts on the embryonic development, including lethality, hatching rate, heart rate and teratogenic effects. Compared to the contaminant existed alone, combined pollution produced stronger toxicity, which appeared as the decreasing of heart rate and hatching rate, and the increasing of malformation of zebrafish embryos. After 96 h exposure, the reactive oxygen species (ROS) levels in zebrafish embryos were increased significantly, revealing that EATC-Cd co-exposure resulted in potential oxidative stress-induced damage. Acridine orange (AO) staining showed that combined exposure resulted in stronger cell apoptosis. The potential health risks of the combined pollution of EATC and Cd should be paid more attention to higher level vertebrates and humans.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Animais , Antibacterianos/farmacologia , Cádmio/metabolismo , Embrião não Mamífero , Metais Pesados/metabolismo , Estresse Oxidativo , Tetraciclina/metabolismo , Tetraciclinas/farmacologia , Poluentes Químicos da Água/metabolismo , Peixe-Zebra/metabolismo
7.
Sci Total Environ ; 864: 160974, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36563757

RESUMO

Humic substances are widely present in aquatic environments. Due to the high affinity of humic substances for metals, the interactions have been particularly studied. To assess the effect of humic acid (HA) on submerged macrophytes and biofilms exposed to heavy metal stress, Vallisneria natans was exposed to solutions containing different concentrations of HA (0.5-2.0 mg·L-1), Pb2+ (1 mg·L-1) and Cd2+ (1 mg·L-1). Results suggested that HA positively affected the plant growth and alleviated toxicity by complexing with metals. HA increased the accumulation of metals in plant tissues and effectively induced antioxidant responses and protein synthesis. It was also noted that the exposure of HA and metals promoted the abundance and altered the structure of microbial communities in biofilms. Moreover, the positive effects of HA were considered to be related to the expression of related genes resulting from altered DNA methylation levels, which were mainly reflected in the altered type of demethylation. These results demonstrate that HA has a protective effect against heavy metal stress in Vallisneria natans by inducing effective defense mechanisms, altering biofilms and DNA methylation patterns in aquatic ecosystems.


Assuntos
Hydrocharitaceae , Metais Pesados , Microbiota , Substâncias Húmicas/análise , Cádmio/metabolismo , Chumbo/toxicidade , Chumbo/metabolismo , Metais Pesados/metabolismo , Hydrocharitaceae/metabolismo
8.
Int J Biol Macromol ; 228: 732-743, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36563811

RESUMO

Plant AT-rich sequence and zinc-binding (PLATZ) proteins are a class of plant-specific zinc finger transcription factors that perform critical functions in plant development and resistance. However, the function of PLATZs in heavy metal tolerance has not yet been investigated. Moreover, only a few PLATZ proteins have been functionally characterized in tree species. In this study, we identified 18 PtPLATZ genes in Populus trichocarpa, an important woody model plant, and classified them into five groups. PtPLATZ genes attributed to the same clade usually possess similar exon-intron structures containing two or three introns, as well as a similar motif composition. Furthermore, chromosomal location analysis indicated an uneven distribution of PtPLATZ genes on 13 of the 19 Populus chromosomes. Promoter cis-acting element prediction and gene expression analysis showed that PtPLATZ genes were highly responsive to heavy metal stress. Heterologous yeast expression revealed that PtPLATZ1, PtPLATZ2, PtPLATZ3, PtPLATZ4, PtPLATZ8 and PtPLATZ9 are significantly involved in Cd tolerance. In addition, transgenic expression of PtPLATZ3 significantly enhanced Cd tolerance and accumulation, slowed the decline in chlorophyll content, maintained membrane integrity in Populus, and increased the expression of genes related to Cd tolerance and accumulation. In conclusion, our results suggest the potential of PtPLATZ3 to improve Cd tolerance and accumulation in Populus, which is of great significance for phytoremediation.


Assuntos
Metais Pesados , Populus , Cádmio/toxicidade , Cádmio/metabolismo , Populus/genética , Populus/metabolismo , Biodegradação Ambiental , Metais Pesados/toxicidade , Metais Pesados/metabolismo , Íntrons , Proteínas de Plantas/química , Regulação da Expressão Gênica de Plantas
9.
J Agric Food Chem ; 70(51): 16037-16049, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36511327

RESUMO

Characterized by strong acidity, chelating ability, and reducing ability, oxalic acid, a low molecular weight dicarboxylic organic acid, plays important roles in the regulation of plant growth and development, the response to both biotic and abiotic stresses such as plant defense and heavy metals detoxification, and food quality. The metabolism of oxalic acid has been well-studied in microorganisms, fungi, and animals but remains less understood in plants. However, excessive accumulation of oxalic acid is detrimental to plants. Therefore, the level of oxalic acid has to be precisely controlled in plant tissues. In this review, we summarize the metabolism, function, and regulation of oxalic acid in plants, and we discuss solutions such as agricultural practices and plant biotechnology to manipulate oxalic acid metabolism to regulate plant responses to both external stimuli and internal developmental cues.


Assuntos
Metais Pesados , Plantas , Animais , Plantas/metabolismo , Ácido Oxálico/metabolismo , Fungos/metabolismo , Biotecnologia , Metais Pesados/metabolismo
10.
Int J Mol Sci ; 23(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36499062

RESUMO

Cadmium (Cd) or nickel (Ni) were applied as a foliar spray (1 µM solution over one month) to mimic air pollution and to monitor metabolic responses and oxidative stress in the pteridophyte species. Exogenous metals did not affect the metal content of the soil and had relatively little effect on the essential elements in leaves or rhizomes. The amounts of Cd and Ni were similar in treated leaves (7.2 µg Cd or 5.3 µg Ni/g DW in mature leaves compared with 0.4 µg Cd or 1.2 µg Ni/g DW in the respective control leaves), but Ni was more abundant in rhizomes (56.6 µg Ni or 3.4 µg Cd/g DW), resulting in a higher Cd translocation and bioaccumulation factor. The theoretical calculation revealed that ca. 4% of Cd and 5.5% of Ni from the applied solution per plant/pot was absorbed. Excess Cd induced stronger ROS production followed by changes in SOD and CAT activities, whereas nitric oxide (NO) stimulation was less intense, as detected by confocal microscopy. The hadrocentric vascular bundles in the petioles also showed higher ROS and NO signals under metal excess. This may be a sign of increased ROS formation, and high correlations were observed. Proteins and amino acids were stimulated by Cd or Ni application in individual organs, whereas phenols and flavonols were almost unaffected. The data suggest that even low levels of exogenous metals induce an oxidative imbalance, although no visible damage is observed, and that the responses of ferns to metals are similar to those of seed plants or algae.


Assuntos
Adiantum , Gleiquênias , Metais Pesados , Poluentes do Solo , Cádmio/metabolismo , Metais Pesados/metabolismo , Gleiquênias/metabolismo , Adiantum/metabolismo , Poluentes do Solo/toxicidade , Poluentes do Solo/química , Plantas/metabolismo
11.
Ecotoxicol Environ Saf ; 248: 114281, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36379073

RESUMO

Although numerous studies have investigated that atmospheric fine particulate matter (PM2.5) can be toxic to environmental organisms, the research on the reproductive toxicity of PM2.5 is limited, and the key toxic components and underlying mechanisms remain unknown. In this work, PM2.5 samples of four seasons in Nanjing from March 1, 2021, to February 28, 2022 were collected and the chemical components were analyzed. Caenorhabditis elegans (C. elegans) was employed to conduct the toxicological testing. The reproductive toxicity of PM2.5 to C. elegans in different seasons was evaluated by multiple reproductive endpoints. Exposure to high concentrations of PM2.5 significantly decreased the brood size and the number of fertilized eggs in utero. PM2.5 exposure also increased the number of germ cell corpses and caused abnormal expression of apoptosis-related genes (ced-9, ced-4, and ced-3), which confirmed that PM2.5 induced germline apoptosis. In addition, PM2.5 exposure significantly increased the production of reactive oxygen species (ROS) in C. elegans and the fluorescence intensity of HUS-1 protein in of transgenic strain WS1433. Meanwhile, the expression of genes related to DNA damage (cep-1, clk-2, egl-1, and hus-1) and oxidative stress (mev-1, isp-1, and gas-1) also significantly altered in C. elegans, suggesting induction of DNA damage and oxidative stress. According to Pearson correlation analyses, DNA damage and oxidative stress were significantly correlated with multiple reproductive endpoints in C. elegans. Thus, it was speculated that PM2.5 caused reproductive dysfunction and germ cell apoptosis in C. elegans may be by inducing ROS and DNA damage. In addition, heavy metals in PM2.5 were significantly correlated with multiple endpoints at physiological and biochemical, suggesting that the heavy metals might be an important contributor to the reproductive toxicity induced by PM2.5.


Assuntos
Metais Pesados , Material Particulado , Animais , Material Particulado/análise , Caenorhabditis elegans/metabolismo , Estações do Ano , Espécies Reativas de Oxigênio/metabolismo , Metais Pesados/metabolismo , Apoptose
12.
Environ Pollut ; 314: 120303, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36181940

RESUMO

The coexistence of di (2-ethylhexyl) phthalate (DEHP), Cd, and Zn poses a serious challenge to soil ecosystems. This study aimed to evaluate the phytoremediation potential of rice assisted with a plant growth promoting rhizobacteria (PGPR) consortium for the remediation of DEHP, Cd, and Zn co-contaminated soil. The consortium consisted of four bacterial strains, all of which exhibited Cd-Zn resistance and DEHP degradability. The results showed that the rice assisted by the bacterial consortium dissipated 86.1% DEHP while removing 76.0% Cd2+ and 92.2% Zn2+ from soil within 30 d. The presence of the PGPR consortium promoted plant growth and improved soil enzymatic activity, which may have helped enhance the removal of DEHP and heavy metals from the soil. Moreover, the application of the consortium modified the bacterial community and increased the relative abundance of bacteria related to DEHP degradation (Sphingomonas, Xanthobacteraceae), heavy metal immobilization (Massilia), and soil nutrient cycling (Nitrospira, Vicinamibacterales), which promoted plant growth and the removal of DEHP and heavy metals from soil. Notably, the DEHP and heavy metal contents in rice decreased substantially during the phytoremediation process. Therefore, the PGPR consortium could be beneficial for enhancing the removal of DEHP and heavy metals from the soil, without inducing the accumulation of these pollutants in rice. In general, this study confirmed that the combined use of rice and the PGPR consortium could remedy DEHP and heavy metal co-contaminated soil economically and ecologically without simultaneously posing risks for rice consumption.


Assuntos
Dietilexilftalato , Metais Pesados , Oryza , Poluentes do Solo , Biodegradação Ambiental , Rizosfera , Solo , Oryza/metabolismo , Cádmio , Poluentes do Solo/análise , Ecossistema , Metais Pesados/metabolismo , Bactérias/metabolismo , Fotossíntese , Homeostase
13.
Mol Biol Rep ; 49(12): 12227-12238, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36269534

RESUMO

Heavy metal exposure has soared due to the twentieth century's industrial activity. The most common heavy metals that lead to human poisoning are mercury, cadmium, and arsenic. Acute or chronic poisoning may develop following exposure to water, air, or food, so the bioaccumulation of these heavy metals causes harmful consequences in various human tissues and organs. Heavy metals interfere with biological functions such as growth, proliferation, differentiation, damage repair, and apoptosis. The mechanisms of action for these metals to cause toxicity are similar, including forming reactive oxygen species (ROS), weakening antioxidant defenses, enzyme inactivation, and oxidative stress. Heavy metal exposure is mainly associated with skin, liver, prostate, lung, urinary bladder, thyroid, and kidney cancers, as well as causing gastrointestinal malignancies. Several microRNAs (miRNAs or miRs) have been involved in various human cancers due to the dysregulation of miRNA function. Recent investigations have confirmed that microRNA dysregulation plays a role in the carcinogenesis of many tissues. This review presents the data concerning arsenic, cadmium, and mercury metals and their contamination sources, human exposure, toxicity, and inducing malignant transformations such as carcinogenicity in in-vitro or in-vivo specimens or dysregulated expression of microRNAs.


Assuntos
Arsênio , Mercúrio , Metais Pesados , MicroRNAs , Humanos , Arsênio/toxicidade , Cádmio/toxicidade , MicroRNAs/genética , Metais Pesados/toxicidade , Metais Pesados/metabolismo , Mercúrio/toxicidade
14.
Metab Brain Dis ; 37(8): 2777-2782, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36214979

RESUMO

Cadmium (Cd) is a toxicant metal that risks human and animal health. Nowadays, the vital role of Aquaporin-4 (AQP-4) in brain and gut cell permeability has gathered too much attention to protecting against heavy metals. Studies have shown that heavy metals can harm the body due to oxidative stress. Probiotics are known for their health-beneficial effects and establish as dietary adjuncts mainly for their antioxidant properties. This study investigated the impact of a novel probiotic combination including Lactobacillus casei IBRC-M10783, Lactobacillus rhamnosus IBRC-M10782, and Lactobacillus helveticus TG-34 on the AQP-4 gene expression in CdCl2-induced Wistar rats. Rats were divided into three groups and received a specific dose of CdCl2 or probiotics. The AQP-4 expression level had estimated by Real-Time PCR in both the intestine and brain. These results showed a significant reduction in AQP-4 gene expression in the probiotic treatment group compared to the CdCl2 control group in the intestine and brain for the first time. Our research showed that consuming a probiotic mixture of L. casei, L. rhamnosus, and L. helveticus can reduce the expression of the aquaporin-4 gene in the brain and intestine of rats exposed to Cadmium, which can be promising in the field of aquaporin-4 regulation.


Assuntos
Aquaporinas , Metais Pesados , Probióticos , Humanos , Ratos , Animais , Cádmio/toxicidade , Cloreto de Cádmio/toxicidade , Ratos Wistar , Probióticos/farmacologia , Probióticos/uso terapêutico , Metais Pesados/metabolismo , Metais Pesados/farmacologia , Intestinos , Encéfalo/metabolismo , Expressão Gênica , Aquaporinas/metabolismo , Aquaporinas/farmacologia
15.
Planta ; 256(5): 94, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36205775

RESUMO

MAIN CONCLUSION: Negatively charged carboxy-polystyrene (CPS) and positively charged amino-polystyrene (NPS) could significantly inhibit the biomass and flavonoid content of dandelion roots and leaves, and the inhibitory effect of NPS was stronger than that of CPS. The increasingly serious pollution of microplastics and heavy metals is likely to affect the efficacy of flavonoids synthesized by dandelion in natural medicine fields. Therefore, we combined hydroponic experiments with computational chemistry (Gaussian and autodock analysis) to explore the mechanism by which amino-polystyrene (NPS), carboxy-polystyrene (CPS), and lead affect the flavonoid biosynthetic pathway in dandelion (Taraxacum asiaticum Dahlst). Our results show that CPS and NPS could significantly inhibit the biomass and flavonoid content of dandelion roots and leaves, and the inhibitory effect of NPS was stronger than that of CPS. Mechanistic studies showed that CPS and NPS increased the content of O2- and H2O2 in dandelion roots and leaves, causing membrane lipid peroxidation, resulting in cell damage and decreased biomass. CPS and NPS inhibited related enzymatic activities by affecting their tertiary structures, resulting in a decrease in phenolic acid, coumaroyl-CoA, and flavonoid content. Dandelion preferred to absorb positively charged NPS compared to negatively charged CPS, but CPS inhibited the uptake of Pb by dandelion more strongly than NPS. Pb promoted CPS agglomeration and increased the surface positive charge of CPS through coordination bonds and hydrogen bonds, so more CPS entered dandelion under CPS + Pb treatment than under CPS alone. Although NPS and CPS reduced the uptake of Pb by dandelion, the biomass and flavonoid contents of dandelion were lower than those of single Pb treatment because of the higher toxicity of NPS and CPS than Pb. Pb significantly increased the effect of CPS on the root biomass of dandelion compared with CPS alone by increasing the positive charge of CPS. We suggest that microplastics with different charges and lead composite pollution inhibit dandelion flavonoid biosynthesis and provide a reference for the loss of dandelion medicinal components and economic value.


Assuntos
Metais Pesados , Taraxacum , Vias Biossintéticas , Coenzima A/metabolismo , Flavonoides/metabolismo , Peróxido de Hidrogênio/metabolismo , Chumbo/toxicidade , Metais Pesados/metabolismo , Microplásticos , Plásticos/metabolismo , Taraxacum/química , Taraxacum/metabolismo
16.
Genes (Basel) ; 13(10)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36292652

RESUMO

The content of metal ions in fruits is inseparable from plant intake of trace elements and health effects in the human body. To understand metal ion content in the fruit and pericarp of melon (Cucumis melo L.) and the candidate genes responsible for controlling this process, we analyzed the metal ion content in distinct parts of melon fruit and pericarp and performed RNA-seq. The results showed that the content of metal ions in melon fruit tissue was significantly higher than that in the pericarp. Based on transcriptome expression profiling, we found that the fruit and pericarp contained elevated levels of DEGs. GO functional annotations included cell surface receptor signaling, signal transduction, organic substance metabolism, carbohydrate derivative binding, and hormone-mediated signaling pathways. KEGG pathways included pectate lyase, pentose and glucuronate interconversions, H+-transporting ATPase, oxidative phosphorylation, plant hormone signal transduction, and MAPK signaling pathways. We also analyzed the expression patterns of genes and transcription factors involved in hormone biosynthesis and signal transduction. Using weighted gene co-expression network analysis (WGCNA), a co-expression network was constructed to identify a specific module that was significantly correlated with the content of metal ions in melon, after which the gene expression in the module was measured. Connectivity and qRT-PCR identified five candidate melon genes, LOC103501427, LOC103501539, LOC103503694, LOC103504124, and LOC107990281, associated with metal ion content. This study provides a theoretical basis for further understanding the molecular mechanism of heavy metal ion content in melon fruit and peel and provides new genetic resources for the study of heavy metal ion content in plant tissues.


Assuntos
Cucumis melo , Cucurbitaceae , Metais Pesados , Oligoelementos , Humanos , Cucumis melo/genética , Cucurbitaceae/genética , Reguladores de Crescimento de Plantas/metabolismo , Oligoelementos/metabolismo , Metais Pesados/toxicidade , Metais Pesados/metabolismo , Fatores de Transcrição/metabolismo , Hormônios , Pentoses/metabolismo , Glucuronatos/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Receptores de Superfície Celular/metabolismo
17.
Int J Mol Sci ; 23(20)2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36293069

RESUMO

Experimental liver injury with hepatocelluar necrosis and abnormal liver tests is caused by exposure to heavy metals (HMs) like aluminum, arsenic, beryllium, cadmium, chromium, cobalt, copper, iron, lead, mercury, molybdenum, nickel, platinum, thallium, titanium, vanadium, and zinc. As pollutants, HMs disturb the ecosystem, and as these substances are toxic, they may affect the health of humans and animals. HMs are not biodegradable and may be deposited preferentially in the liver. The use of animal models can help identify molecular and mechanistic steps leading to the injury. HMs commonly initiate hepatocellular overproduction of ROS (reactive oxygen species) due to oxidative stress, resulting in covalent binding of radicals to macromolecular proteins or lipids existing in membranes of subcellular organelles. Liver injury is facilitated by iron via the Fenton reaction, providing ROS, and is triggered if protective antioxidant systems are exhausted. Ferroptosis syn pyroptosis was recently introduced as mechanistic concept in explanations of nickel (Ni) liver injury. NiCl2 causes increased iron deposition in the liver, upregulation of cyclooxygenase 2 (COX-2) protein and mRNA expression levels, downregulation of glutathione eroxidase 4 (GPX4), ferritin heavy chain 1 (FTH1), nuclear receptor coactivator 4 (NCOA4) protein, and mRNA expression levels. Nickel may cause hepatic injury through mitochondrial damage and ferroptosis, defined as mechanism of iron-dependent cell death, similar to glutamate-induced excitotoxicity but likely distinct from apoptosis, necrosis, and autophagy. Under discussion were additional mechanistic concepts of hepatocellular uptake and biliary excretion of mercury in exposed animals. For instance, the organic anion transporter 3 (Oat3) and the multidrug resistance-associated protein 2 (Mrp2) were involved in the hepatic handling of mercury. Mercury treatment modified the expression of Mrp2 and Oat3 as assessed by immunoblotting, partially explaining its impaired biliary excretion. Concomitantly, a decrease in Oat3 abundance in the hepatocyte plasma membranes was observed that limits the hepatic uptake of mercury ions. Most importantly and shown for the first time in liver injury caused by HMs, titanium changed the diversity of gut microbiota and modified their metabolic functions, leading to increased generation of lipopolysaccharides (LPS). As endotoxins, LPS may trigger and perpetuate the liver injury at the level of gut-liver. In sum, mechanistic and molecular steps of experimental liver injury due to HM administration are complex, with ROS as the key promotional compound. However, additional concepts such as iron used in the Fenton reaction, ferroptosis, modification of transporter systems, and endotoxins derived from diversity of intestinal bacteria at the gut-liver level merit further consideration.


Assuntos
Arsênio , Poluentes Ambientais , Mercúrio , Metais Pesados , Transportadores de Ânions Orgânicos , Humanos , Animais , Níquel/metabolismo , Zinco/metabolismo , Cobre/metabolismo , Cádmio/metabolismo , Cobalto/metabolismo , Vanádio/metabolismo , Molibdênio/metabolismo , Alumínio/metabolismo , Cromo/metabolismo , Arsênio/toxicidade , Arsênio/metabolismo , Titânio/metabolismo , Berílio/metabolismo , Ferro/metabolismo , Platina/metabolismo , Tálio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ciclo-Oxigenase 2/metabolismo , Mercúrio/toxicidade , Antioxidantes/metabolismo , Lipopolissacarídeos/metabolismo , Ecossistema , Apoferritinas/metabolismo , Metais Pesados/toxicidade , Metais Pesados/metabolismo , Fígado/metabolismo , Poluentes Ambientais/metabolismo , Glutationa/metabolismo , Necrose/metabolismo , Glutamatos/metabolismo , Coativadores de Receptor Nuclear , Transportadores de Ânions Orgânicos/metabolismo , RNA Mensageiro/metabolismo
18.
Artigo em Inglês | MEDLINE | ID: mdl-36231857

RESUMO

Rhamnolipids, a type of biosurfactant, represent a potential strategy for both enhancing organismic resistance and in situ remediation of heavy metals contaminations. In-depth study of the mechanism of rhamnolipids synthesis in response to heavy metals stress, is indispensable for a wide use of biosurfactant-secreting microbes in bioremediation. In this study, we employed the wild-type and the rhlAB deficient strain (ΔrhlAB) of Pseudomonas aeruginosa, a prototypal rhamnolipids-producing soil microorganism, to investigate its responses to cadmium resistance based on its physicochemical, and physiological properties. Compared with the wild-type strain, the ΔrhlAB were more sensitive to Cd-stress at low Cd concentration (<50 mg/L), whereas there was little difference in sensitivity at higher Cd concentrations, as shown by spot titers and cell viability assays. Secreted rhamnolipids reduced intracellular Cd2+ accumulation to alleviate Cd2+ stress, whereas endogenous rhamnolipids played a limited role in alleviating Cd2+ stress. Synthesized rhamnolipids exhibited a higher critical micelle concentration (CMC) (674.1 mg/L) and lower emulsification index (4.7%) under high Cd-stress, while these parameters showed no obvious changes. High Cd-stress resulted in high hydrophilic wild-type bacterial surface and lower bioremediation ability. This study could advance a deeper understanding of the mechanism of cadmium resistance and provide a theoretical foundation for the application of biosurfactant and biosurfactant-secreted bacterium in contaminant bioremediation.


Assuntos
Cádmio , Metais Pesados , Bactérias/metabolismo , Biodegradação Ambiental , Cádmio/metabolismo , Cádmio/toxicidade , Glicolipídeos , Metais Pesados/metabolismo , Micelas , Pseudomonas aeruginosa/genética , Solo , Tensoativos/química , Tensoativos/farmacologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-36231984

RESUMO

Cadmium toxicity is one of the deleterious abiotic factors that reduce wheat production. Two different cultivars (Akbar and Dilkash) were compared for their cadmium (0, 40 and 80 mg/kg) tolerance and responses towards Bacillus subtilis NA2, Aspergillus niger PMI-118 and L-proline. Both microbes were tested for heavy metal tolerance and production of various plant hormones and biological active enzyme characteristics under normal and cadmium stress. A completely randomized design (two cultivars × four treatments × three cadmium levels × three replicates) was adopted using distilled water as a control. The growth promotion potential of these strains under cadmium stress was determined by N-fixation, IAA synthesis, P-solubilization, amylase and proteases production. A pot experiment under controlled conditions was conducted to evaluate the effect of bacteria, fungi, and L-proline under cadmium stress. It was indicated from the result that plant biomass (46.43%), shoot length (22.40%), root length (25.06%), chlorophyll (17.17%), total sugars (27.07%), total proteins (86.01%) and ascorbic acid (83.27%) were improved with inoculation under control and cadmium stress. The accumulation of total flavonoids (48.64%), total phenolics (24.88%), hydrogen peroxide (53.96%) and activities of antioxidant enzymes CAT (26.37%) and APX (43.71%) were reduced in the plants treated with bacteria, fungi and L-proline than those under control. With parallel aids, Bacillus subtilis NA2 showed a higher cadmium tolerance and plant growth stability as compared to Aspergillus niger PMI-118 and L-proline and may be adopted in the future.


Assuntos
Metais Pesados , Poluentes do Solo , Amilases , Antioxidantes/metabolismo , Ácido Ascórbico/farmacologia , Aspergillus niger , Bacillus subtilis , Biodegradação Ambiental , Cádmio/metabolismo , Clorofila/metabolismo , Flavonoides/farmacologia , Peróxido de Hidrogênio/metabolismo , Metais Pesados/metabolismo , Peptídeo Hidrolases/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Plantas/metabolismo , Prolina/metabolismo , Prolina/farmacologia , Poluentes do Solo/análise , Açúcares/metabolismo , Triticum/metabolismo , Água/metabolismo
20.
J Biotechnol ; 359: 65-74, 2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-36184003

RESUMO

Heavy metal contamination is a global issue, with cadmium (Cd2+) and its treatment becoming major environmental challenge that could be solved by microbial restoration, an eco-friendly technique. Serratia marcescens KMR-3 exhibits high tolerance and removal rate of Cd2+ (≤500 mg/L). Here, we aimed to explore mechanisms underlying tolerance to and removal of Cd2+ by KMR-3. Scanning electron microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectrometry were conducted to analyze characteristics of the KMR-3 biofilm and Cd2+ combined forms. The results revealed varying degrees of cell adhesion, membrane thickening, and shrinkage on the surface of the bacteria. The binding elements, electronic binding energy, and functional groups on the surface of the bacteria exhibited changes. Furthermore, the biofilm amount following treatment with Cd2+ was 1.5-3 times higher than that in the controls, treatment with Cd2+ substantially enhanced biofilm generation and increased Cd2+ adsorption. Cd2+ adsorption by its own secondary metabolite prodigiosin produced by KMR-3 was enhanced by 19.5 % compared with that observed without prodigiosin. Through transcriptome sequencing and RT-qPCR, we observed that Znu protein-chelating system regulated gene expression (znuA, znuB, and znuC), and the efflux mechanism of the P-type ATPase regulated the expression of genes (zntA, zntB, and zntR), which were significantly enhanced. Through the combined action of various strategies, KMR-3 demonstrated a high tolerance and removal ability of Cd2+, providing a theoretical basis to treat Cd2+ pollution.


Assuntos
Metais Pesados , ATPases do Tipo-P , Serratia marcescens/genética , Serratia marcescens/química , Serratia marcescens/metabolismo , Prodigiosina/metabolismo , Cádmio , Metais Pesados/metabolismo , ATPases do Tipo-P/metabolismo
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