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1.
Indian J Public Health ; 66(1): 27-32, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35381710

RESUMO

Background: Extensive evidence of elevated chromium (Cr) in the surface and groundwater exists. However, the importance of exposure toward Cr-associated health risks in areas with tanneries is still often neglected. These situations prompted an independent research study to investigate the views of those close-knit communities who are being directly affected by this tannery village. Objectives: To establish an understanding of the local demographics and; exploratory data analysis (EDA) to discover patterns in the occurrence of diseases; measure the awareness of residents of the presence of Cr and its harmful health effects. Methods: The EDA technique was used to conduct survey studies on data to uncover patterns, identify anomalies, test hypotheses, and validate assumptions using summary statistics and graphical representations. Results: Out of 14 diseases directly linked to high Cr toxicity, the study reported high levels of diarrhea, epigastric pain, and moderate-to-severe cases of vertigo among those aged more than 22 years. With over 90 active tanneries and toxic Cr released to the environment in a town of <78 km2 area (1.2 tannery/km), there are only 15 hospitals (0.2 hospitals/km) for the population currently accommodating more than a quarter-million people daily (3205 people/km). Conclusion: New mitigation strategies must be put forth to alleviate the negative impacts of the tanneries on the residents and nature most affected as well as the population as a whole.


Assuntos
Cromo , Saúde Pública , Adulto , Cromo/análise , Cromo/toxicidade , Humanos , Índia/epidemiologia , Curtume , Águas Residuárias , Adulto Jovem
2.
Ecotoxicol Environ Saf ; 237: 113532, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35472558

RESUMO

Industrial production, ore smelting and sewage disposal plant can discharge large amounts of heavy metals every year, which may contaminate soil, water and air, posing a great threat to ecological environment and animal production. Hexavalent chromium [Cr (VI)], a recognized metallic contaminant, has been shown to impair kidney, liver and gastrointestinal tract of many species, but little is known about the gut microbial characteristics of chickens exposed to Cr (VI). Herein, this study characterized the gut microbial alternations of chickens exposed to Cr (VI). Results indicated that the gut microbial alpha-diversity in chickens exposed to Cr (VI) decreased significantly, accompanied by a distinct shifts in taxonomic composition. Microbial taxonomic analysis demonstrated that the preponderant phyla (Firmicutes, Bacteroidetes, Proteobacteria and Epsilonbacteraeota) were the same in both groups, but different in types and relative abundances of dominant genera. Moreover, some bacterial taxa including 2 phyla and 47 genera significantly decreased, whereas 3 phyla and 17 genera significantly increased during Cr (VI) exposure. Among decreased taxa, 9 genera (Coprobacter, Ruminococcus_1, Faecalicoccus, Eubacterium_nodatum_group, Parasutterella, Slackia, Barnesiella, Family_XIII_UCG-001 and Collinsella) even cannot be detected. In conclusion, this study revealed that Cr (VI) exposure dramatically decrased the gut microbial diversity and altered microbial composition of chickens. Additionally, this study also provided a theoretical basis for relieving Cr (VI) poisoning from the perspective of gut microbiota.


Assuntos
Galinhas , Microbioma Gastrointestinal , Animais , Bacteroidetes , Cromo/toxicidade , Firmicutes , Homeostase
3.
PLoS One ; 17(4): e0266898, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35421180

RESUMO

Oral exposure to chromium hexavalent [Cr(VI)] has disastrous impacts and affects many people worldwide. Cr(VI) triggers neurotoxicity via its high oxidation potential by generating high amount of ROS. Meanwhile, alginates are known by their chelating activity and ability to bind heavy metals and toxins, in addition to their antioxidant, anti-inflammatory, and anti-apoptotic activities. So, this study aimed to explore the neuroprotective potential of sodium alginate (SA) against cellular injury, DNA damage, macromolecule alterations, and apoptosis induced by oral ingestion of Cr. Forty Wistar male rats were divided into 4 groups; group I: standard control ingested with the vehicle solution, group II: Cr-intoxicated group received 10 mg/kg b.w. of potassium dichromate orally by gavage and kept without treatment, group III: SA group in which rats were orally exposed to 200 mg/kg b.w. of SA only, and group IV: SA-treated group that received 200 mg/kg b.w. of SA along with Cr for 28 consecutive days. Neurotransmitters such as Acetyl choline esterase (AchE), Monoamine oxidase A (MAOA) concentrations, Dopamine (DA) and 5-Hydroxytryptamine (5-HT) levels were assessed in brain homogenate tissues. Neurobiochemical markers; NAD+ and S100B protein were investigated in the brain tissues and serum, respectively. Levels of HSP70, caspase-3, protein profiling were evaluated. DNA damage was determined using the Comet assay. Results revealed a significant reduction in the AchE and MAOA concentrations, DA, 5-HT, and NAD+ levels, with an increase in the S100B protein levels. Cr(VI) altered protein pattern and caused DNA damage. High levels of HSP70 and caspase-3 proteins were observed. Fortunately, oral administration of SA prevented the accumulation of Cr in brain homogenates and significantly improved all investigated parameters. SA attenuated the ROS production and relieved the oxidative stress by its active constituents. SA can protect against cellular and DNA damage and limit apoptosis. SA could be a promising neuroprotective agent against Cr(VI)-inducing toxicity.


Assuntos
Fármacos Neuroprotetores , Alginatos/farmacologia , Animais , Encéfalo/metabolismo , Caspase 3/metabolismo , Cromo/toxicidade , Masculino , NAD/metabolismo , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Serotonina/metabolismo
4.
Chemosphere ; 298: 134239, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35292278

RESUMO

Environmental (e)DNA metabarcoding holds great promise for biomonitoring and ecotoxicological applications. However, few studies have compared the performance of eDNA versus eRNA metabarcoding in assessing organismal response to marine pollution, in experimental conditions. Here, we performed a chromium (Cr)-spiked mesocosm experimental test on benthic foraminiferal community to investigate the effects on species diversity by analysing both eDNA and eRNA metabarcoding data across different Cr concentrations in the sediment. Foraminiferal diversity in the eRNA data showed a significant negative correlation with the Cr concentration in the sediment, while a positive response was observed in the eDNA data. The foraminiferal OTUs exhibited a higher turnover rate in eRNA than in the eDNA-derived community. Furthermore, in the eRNA samples, OTUs abundance was significantly affected by the Cr gradient in the sediment (Pseudo-R2 = 0.28, p = 0.05), while no significant trend was observed in the eDNA samples. The correlation between Cr concentration and foraminiferal diversity in eRNA datasets was stronger when the less abundant OTUs (<100 reads) were removed and the analyses were conducted exclusively on OTUs shared between eRNA and eDNA datasets. This indicates the importance of metabarcoding data filtering to capture ecological impacts, in addition to using the putatively active organisms in the eRNA dataset. The comparative analyses on foraminiferal diversity revealed that eRNA-based metabarcoding can better assess the response to heavy metal exposure in presence of subtle concentrations of the pollutant. Furthermore, our results suggest that to unlock the full potential for ecosystem assessment, eDNA and eRNA should be studied in parallel to control for potential sequence artifacts in routine ecosystem surveys.


Assuntos
Ecossistema , Foraminíferos , Biodiversidade , Cromo/toxicidade , Código de Barras de DNA Taxonômico/métodos , Monitoramento Ambiental/métodos , Foraminíferos/genética , RNA
5.
Environ Sci Technol ; 56(6): 3503-3513, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35245034

RESUMO

In this study, the toxicity of hexavalent chromium [Cr(VI)] reduced by citric acid in ice was measured using representative aquatic model invertebrates (i.e., rotifer, water flea, amphipod, and polychaete) and a vertebrate (zebrafish) by analyzing short- and/or long-term endpoints that are frequently applied to each animal. Cr(VI) reduction in the presence of citric acid was markedly enhanced in the ice phase compared to that in an aqueous solution through the freeze concentration effect. The highly concentrated Cr(VI) and citric acid in ice grain boundaries were also confirmed using in situ cryogenic confocal Raman spectroscopy. Overall, exposure to Cr(VI) resulted in higher acute and/or chronic effects on aquatic animals, such as drastic mortality, growth inhibition, and decrease in offspring number, whereas the animals were increasingly tolerant to Cr(VI) that was reduced in the ice phase. Sublethal concentrations of Cr(VI) significantly decreased the antioxidant capacity in the aquatic animals. However, when the same concentrations of Cr(VI) were reduced in ice, these treatments showed no modulation or increase in the antioxidant defense system. Taken together, our results suggest that Cr(VI) reduction into Cr(III) was successfully achieved in ice and that this methodology can decrease the actual toxicity of Cr(VI) in aquatic animals.


Assuntos
Gelo , Poluentes Químicos da Água , Animais , Antioxidantes , Cromo/química , Cromo/toxicidade , Ácido Cítrico , Oxirredução , Poluentes Químicos da Água/química , Peixe-Zebra
6.
Environ Toxicol Pharmacol ; 92: 103846, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35288336

RESUMO

Environmental contamination by heavy metals (HMs) has impelled searching for stabilization strategies, where the use of zero-valent iron nanoparticles (nZVI) is considered a promising option. We have evaluated the combined effect of Cu(II)-Cr(VI) on two Caenorhabditis elegans strains (N2 and RB1072 sod-2 mutant) in aqueous solutions and in a standard soil, prior and after treatment with nZVI (5% w/w). The results showed that HMs aqueous solutions had an intense toxic effect on both strains. Production of reactive oxygen species and enhanced expression of the heat shock protein Hsp-16.2 was observed, indicating increased HM-mediated oxidative stress. Toxic effects of HM-polluted soil on worms were higher for sod-2 mutant than for N2 strain. However, nZVI treatment significantly diminished all these effects. Our findings highlighted C. elegans as a sensitive indicator for HMs pollution and its usefulness to assess the efficiency of the nanoremediation strategy to decrease the toxicity of Cu(II)-Cr(VI) polluted environments.


Assuntos
Metais Pesados , Nanopartículas , Poluentes do Solo , Animais , Caenorhabditis elegans/genética , Cromo/toxicidade , Cobre/toxicidade , Metais Pesados/análise , Estresse Oxidativo , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Superóxido Dismutase/genética
7.
Reprod Toxicol ; 109: 121-134, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35307491

RESUMO

Environmental contamination with hexavalent chromium, Cr(VI), has been increasing in the United States as well as in developing countries. Exposure to Cr(VI) predisposes the human population to various diseases, including cancer, infertility, and developmental problems in children. Previous findings from our laboratory reported that prenatal exposure to Cr(VI) caused premature ovarian failure through p53-mediated mechanisms. Sirtuin 1 (SIRT1) is an NAD+ -dependent histone deacetylase class III. SIRT1 deacetylates several histones and non-histone proteins such as p53 and NFkB. The current study determines a role for the SIRT1-p53 network in apoptosis induced by Cr(VI) in the ovary and establishes physical interaction between SIRT1 and p53. Adult pregnant dams were given regular drinking water or Cr(VI) (10 ppm potassium dichromate in drinking water, ad libitum), and treated with SIRT1 inhibitor, EX-527 (50 mg/kg body weight, i.p.,), during 9.5 - 14.5 days post-coitum. On postnatal day-1, ovaries from F1 offspring were collected for various analyses. Results indicated that Cr(VI) increased germ cell and somatic cell apoptosis, upregulated acetyl-p53, activated the apoptotic pathway, and inhibited cell survival pathways. Cr(VI) decreased acetyl-p53-SIRT1 co-localization in the ovary. In an immortalized rat granulosa cell line SIGC, Cr(VI) inhibited the physical interaction between SIRT1 and acetyl-p53 by altering the p53:SIRT1 ratio. EX-527 exacerbated Cr(VI)-induced mechanisms. The current study shows a novel mechanism for Cr(VI)-induced apoptosis in the ovary, mediated through the p53-SIRT1 network, suggesting that targeting the p53 pathway may be an ideal approach to rescue ovaries from Cr(VI)-induced apoptosis.


Assuntos
Ovário , Sirtuína 1 , Animais , Apoptose , Cromo/toxicidade , Feminino , Ovário/metabolismo , Gravidez , Ratos , Sirtuína 1/metabolismo , Proteína Supressora de Tumor p53/metabolismo
8.
Chemosphere ; 296: 134065, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35202665

RESUMO

Chromium is one of the highly toxic heavy metals to plant growth and development especially hexavalent chromium (Cr+6) due to its readily available nature and mobility into the environment. The chelating agents and hyperaccumulator plant can contribute to remediating the heavy metals from the contaminated medium. This study was conducted to analyze the role of citric acid and chromium resistant bacteria in castor bean to remediate Cr+6 from the polluted soil. The soil was spiked with different levels of citric acid (0, 2.5, 5 mM) and chromium (0, 10, 20 mg kg-1). The ripened plants were harvested and analyzed for growth parameters, chlorophyll contents, gas exchange parameters, oxidative stress markers, antioxidant enzymes activities and chromium accumulation in different parts of plants. The high concentration of chromium 20 mg kg-1 drastically reduced the plant growth, decreased photosynthetic rate and increased oxidative stress. The application of CA improved the plant growth even at the highest concentration of chromium which was further boosted by the combined application of CA and chromium resistant bacteria. However, the performance of staphylococcus aureus was found significantly better than Bacillus subtilis due to its better ability to tolerate chromium toxicity even at high concentrations. The findings proved that castor bean has excellent potential to tolerate high chromium concentrations and can be effectively used to remediate metals contaminated soil. Further, CA and metal resistant bacteria can significantly enhance the phytoremediation potential of castor bean and other hyperaccumulator plants. The bacteria assisted phytoremediation coupled with the chelating agent can be a practical approach to remediate the metals contaminating soils.


Assuntos
Semente de Rícino , Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Quelantes , Cromo/toxicidade , Ácido Cítrico/farmacologia , Metais Pesados/análise , Ricinus , Solo , Poluentes do Solo/análise
9.
Aging (Albany NY) ; 14(4): 1678-1690, 2022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-35210368

RESUMO

Hexavalent chromium [Cr(VI)] pollution is a serious environmental problem, due to not only its toxicity but also carcinogenesis. Although studies reveal several features of Cr(VI)-induced carcinogenesis, the underlying mechanisms of how Cr(VI) orchestrates multiple mitogenic pathways to promote tumor initiation and progression remain not fully understood. Src/Ras and other growth-related pathways are shown to be key players in Cr(VI)-initiated tumor prone actions. The role of protein kinase C (PKC, an important signal transducer) in Cr(VI)-mediated carcinogenesis has not been thoroughly investigated. In this study, using human bronchial/lung epithelial cells and keratinocytes, we demonstrate that PKC activity is increased by transient or chronic Cr(VI) exposure, which plays no role in the activation of Src/Ras signaling and ROS upregulation by this metal toxin. PKC in chronic Cr(VI)-treated cells stabilizes Bcl-2 to mitigate doxorubicin (an anti-cancer drug)-mediated apoptosis. After the suppression of this kinase by GO6976 (a PKC inhibitor), the cells chronically exposed to Cr(VI) partially regain the sensitivity to doxorubicin. However, when co-suppressed PKC and Ras, the chronic Cr(VI)-treated cells become fully responsive to doxorubicin and are unable to be transformed. Taken together, our study provides a new insight into the mechanisms, in which PKC is an indispensable player and cooperates with other mitogenic pathways to achieve Cr(VI)-induced carcinogenesis as well as to establish drug resistance. The data also suggest that active PKC can serve as a potential biomarker for early detection of health damages by Cr(VI) and therapeutic target for developing new treatments for diseases caused by Cr(VI).


Assuntos
Transformação Celular Neoplásica , Cromo , Carcinogênese/metabolismo , Transformação Celular Neoplásica/metabolismo , Cromo/toxicidade , Doxorrubicina/efeitos adversos , Resistência a Medicamentos , Humanos
10.
Bioengineered ; 13(3): 4923-4938, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35164635

RESUMO

Industrial effluents/wastewater are the main sources of hexavalent chromium (Cr (VI)) pollutants in the environment. Cr (VI) pollution has become one of the world's most serious environmental concerns due to its long persistence in the environment and highly deadly nature in living organisms. To its widespread use in industries Cr (VI) is highly toxic and one of the most common environmental contaminants. Cr (VI) is frequently non-biodegradable in nature, which means it stays in the environment for a long time, pollutes the soil and water, and poses substantial health risks to humans and wildlife. In living things, the hexavalent form of Cr is carcinogenic, genotoxic, and mutagenic. Physico-chemical techniques currently used for Cr (VI) removal are not environmentally friendly and use a large number of chemicals. Microbes have many natural or acquired mechanisms to combat chromium toxicity, such as biosorption, reduction, subsequent efflux, or bioaccumulation. This review focuses on microbial responses to chromium toxicity and the potential for their use in environmental remediation. Moreover, the research problem and prospects for the future are discussed in order to fill these gaps and overcome the problem associated with bacterial bioremediation's real-time applicability.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Biodegradação Ambiental , Cromo/química , Cromo/toxicidade , Humanos , Solo , Águas Residuárias , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
11.
Environ Toxicol ; 37(6): 1288-1296, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35166444

RESUMO

With the spread of hexavalent chromium (Cr(VI)) contamination, Cr(VI)-induced hepatotoxicity has attracted increasing attention in recent years. To date, however, the exact mechanism of Cr(VI) toxicity remains unclear. In this study, we investigated the role of apoptosis signal-regulating kinase 1 (ASK1)/c-Jun amino-terminal kinase (JNK) in Cr(VI)-induced hepatic toxicity and the possible related mechanisms. AML-12 hepatocyte cell-lines were treated with 0, 1, 4, and 16 µmol/Lof Cr(VI) with or without GS-444271 (an ASK1 inhibitor). Adult male mice were administered with 0, 2, 8, and 32 mg/kg body mass (BM)/day of Cr(VI) for 5 days. The level of hepatocyte apoptosis/proliferation, generation of reactive oxygen species (ROS), and expression levels of mRNAs and proteins related to ASK1/JNK and nuclear factor-E2-related factor 2 (Nrf2) signaling were assessed. Results showed that high Cr(VI) exposure induced hepatocyte apoptosis and liver injury by generation of ROS and down-regulation of Nrf2 signaling. In addition, ASK1/JNK signaling activity was upregulated in the Cr(VI)-treated group. Furthermore, GS-444217 treatment significantly rescued Cr(VI)-induced hepatocyte apoptosis and liver dysfunction in vitro and in vivo by down-regulation of ASK1/JNK signaling. Thus, ASK1/JNK signaling appears to play an important role in Cr(VI)-induced hepatocyte apoptosis and liver injury. This study should help improve our understanding of the mechanism of Cr(VI)-induced liver injury and provide support for future investigations on liver disease therapy.


Assuntos
MAP Quinase Quinase Quinase 5 , Fator 2 Relacionado a NF-E2 , Animais , Apoptose , Cromo/metabolismo , Cromo/toxicidade , Hepatócitos/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , MAP Quinase Quinase Quinase 5/metabolismo , Masculino , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo
12.
Toxicol Appl Pharmacol ; 438: 115890, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35101437

RESUMO

Hexavalent chromium [Cr(VI)] is a global environmental pollutant and human lung carcinogen. However, the mechanisms of Cr(VI) carcinogenesis are not well defined. Cr(VI)-altered gene expression has been reported in the literature and is implicated in numerous mechanisms of Cr(VI) carcinogenesis. MicroRNAs (miRNAs) play a key role in controlling gene expression and are associated with carcinogenic mechanisms. To date no studies have evaluated global changes in miRNA expression in human cells after Cr(VI) exposure. We used RNA sequencing to evaluate how a particulate Cr(VI) compound (zinc chromate), the most potent form of Cr(VI), alters global miRNA expression after acute (24 h) or prolonged (72 and 120 h) exposure to 0.1, 0.2 and 0.3 µg/cm2 zinc chromate in an immortalized, non-cancerous human lung cell line (WTHBF-6). Particulate Cr(VI) significantly affected expression of miRNAs at all time points and concentrations tested. We also found the number of significantly downregulated miRNAs increased in a time- and concentration-dependent manner and many miRNAs were upregulated after 24 h exposure at the intermediate concentration tested. Pathway analyses of the differentially expressed miRNAs predicted miRNAs target pathways of Cr(VI) carcinogenesis in a time- and concentration-dependent manner. These data are the first to evaluate global changes in miRNA expression in human lung cells after Cr(VI) exposure and indicate miRNAs may play a key role in pathways of Cr(VI) carcinogenesis.


Assuntos
Carcinogênese/induzido quimicamente , Carcinógenos/toxicidade , Cromo/toxicidade , Pulmão/efeitos dos fármacos , MicroRNAs/genética , Transdução de Sinais/efeitos dos fármacos , Carcinogênese/genética , Linhagem Celular , Cromatos/toxicidade , Expressão Gênica/efeitos dos fármacos , Humanos , Transdução de Sinais/genética , Compostos de Zinco/toxicidade
13.
Environ Pollut ; 301: 119044, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35217142

RESUMO

The untreated effluents released from industrial operations have adverse impacts on human health, environment and socio-economic aspects. Environmental pollution due to chromium is adversely affecting our natural resources and ecosystem. Chromium is hazardous carcinogenic element released from spontaneous activities and industrial procedures. Chromium toxicity, mobility and bioavailability depend mainly on its speciation. Chromium mainly exists in two forms, first as an immobile, less soluble trivalent chromium [Cr(III)] species under reducing conditions whereas hexavalent chromium [Cr(VI)] as a mobile, toxic and bioavailable species under oxidizing conditions. Hexavalent chromium is more pernicious in comparison to trivalent form. Chromium negatively affects crop growth, total yield and grain quality. Exposure of chromium even at low concentration enhances its accretion in cells of human-beings and animals which may show detrimental health effects. Many techniques have been utilized for the elimination of chromium. The selection of the green and cost-efficient technology for treatment of industrial effluent is an arduous task. The present review highlights the problems associated with chromium pollution and need of its immediate elimination by suitable remediation strategies. Further, investigations are required to fill the gaps to overcome the problem of chromium contamination and implementation of sustainable remediation strategies with their real-time applicability on the contaminated sites.


Assuntos
Cromo , Ecossistema , Animais , Cromo/toxicidade , Humanos , Plantas
14.
Ecotoxicol Environ Saf ; 233: 113326, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35203004

RESUMO

Fungi have a promising application prospect in the remediation of heavy-metal wastewater pollution which is a sticky global problem. New marine-derived strain Penicillium janthinellum P1 is of high chromium resistance. However, a comprehensive study of the transcriptomics in Penicillium janthinellum P1 strains is lacking. Firstly, the changing trends of a series of physiological and biochemical indices of P1 strain at 0 M and 1 M Cr concentration were investigated to track the ROS variation. Secondly, transcriptome sequencing of P1 was performed by RNA-Seq sequencing technology. The transcriptome data indicated that 12,352 coding protein regions were predicted, and 6655 differentially expressed genes were identified by DESeq2, of which 4234 genes were up-regulated, and 2421 genes down-regulated. Through further co-expression network of WGCNA analysis, the filtered unigenes were clustered into 19 modules. Combined with the physiological and biochemical findings, the three modules with the highest correlation with the six traits were selected to construct the network, and 52 hub genes were obtained. Furthermore, 10 speculative hub genes related to chromium resistance were selected and verified by real-time PCR. The results were in line with the expected experimental assumption. These results improve our understanding of the transcriptomic dimensions of the high chromium resistance of Penicillium janthinellum P1 strains.


Assuntos
Penicillium , Transcriptoma , Cromo/toxicidade , Perfilação da Expressão Gênica/métodos , Penicillium/genética
15.
Oxid Med Cell Longev ; 2022: 7295224, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35222804

RESUMO

Stress-induced premature senescence may be involved in the pathogeneses of acute liver injury. Hexavalent chromium [Cr(VI)], a common environmental pollutant related to liver injury, likely leads to premature senescence in L02 hepatocytes. However, the underlying mechanisms regarding hepatocyte premature senility in Cr(VI) exposure remain poorly understood. In this study, we found that chronic exposure of L02 hepatocytes to Cr(VI) led to premature senescence characterized by increased ß-galactosidase activity, senescence-associated heterochromatin foci, G1 phase arrest, and decreased cell proliferation. Additionally, Cr(VI)-induced senescent L02 hepatocytes showed upregulated inflammation-related factors, such as IL-6 and fibroblast growth factor 23 (FGF23), which also exhibited reactive oxygen species (ROS) accumulation derived from mitochondria accompanied with increased concentration of intracellular calcium ions (Ca2+) and activity of nuclear factor kappa B (NF-κB). Of note is that ROS inhibition by N-acetyl-Lcysteine pretreatment not only alleviated Cr(VI)-induced premature senescence but also reduced the elevated intracellular Ca2+, activated NF-κB, and secretion of IL-6/FGF23. Intriguingly, the toxic effect of Cr(VI) upon premature senescence of L02 hepatocytes and increased levels of IL-6/FGF23 could be partially reversed by the intracellular Ca2+ chelator BAPTA-AM pretreatment. Furthermore, by utilizing the NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC), we confirmed that NF-κB mediated IL-6/FGF23 to regulate the Cr(VI)-induced L02 hepatocyte premature senescence, whilst the concentration of intracellular Ca2+ was not influenced by PDTC. To the best of our knowledge, our data reports for the first time the role of ROS-Ca2+-NF-κB signaling pathway in Cr(VI)-induced premature senescence. Our results collectively shed light on further exploration of innovative intervention strategies and treatment targeting Cr(VI)-induced chronic liver damage related to premature senescence.


Assuntos
Cálcio/metabolismo , Carcinógenos Ambientais/toxicidade , Senescência Celular/efeitos dos fármacos , Cromo/toxicidade , Hepatócitos/efeitos dos fármacos , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/farmacologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Citocinas/metabolismo , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Inflamação , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , NF-kappa B/antagonistas & inibidores , Espécies Reativas de Oxigênio/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos
16.
J Hazard Mater ; 430: 128430, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35149490

RESUMO

There is uncertainty in quantifying the toxic effects of total chromium (Cr) in the environment by modeling the toxicity of individual Cr(III) or Cr(VI). In the present study, the effects of Cr(III) and Cr(VI) on barley root elongation were investigated in a hydroponic system where Cr(III) and Cr(VI) combination dose-response experiments under monotoxicity concentration, single-dose addition, and fixed concentration ratios were designed to identify and quantify their combined phytotoxicity of one element with various valences. The results show that the calculated mixed toxicity unit values for 50% inhibition (TUmix50) ranged from 1.06 to 1.45, indicating the weak antagonism effects of Cr(III) and Cr(VI) on barley root toxicity. Also, the single-dose group experiment has proved that the EC50 of Cr(VI) was increased from 71.2 µM to 119.9 µM with Cr(III) addition, which suggested that Cr(III) has antagonism on the toxicity of Cr(VI). While EC50 of Cr(III) was not affected by Cr(VI) addition. After introducing the expansion coefficient of Cr(III) on Cr(VI) toxicity, both the extended concentration addition model (e-CA) based on the log-logistic and Weibull equations and the extended independent action model (e-IA) could more accurately predict the barley root elongation under Cr(III) and Cr(VI) interaction. The e-CA model based on the Weibull equation had almost the best correlation coefficient (R2) and lowest root mean square error (RMSE) between the measured and predicted values. Finally, the combined toxicity and antagonism of the same element with co-existing different valences simultaneously were successfully and firstly identified and quantified in the present study.


Assuntos
Hordeum , Cromo/toxicidade , Hidroponia
17.
Environ Toxicol Chem ; 41(4): 1004-1015, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35020957

RESUMO

Manganese (Mn), an essential metal in trace amounts, and chromium (Cr), a nonessential metal to algae, are often found in effluent discharges and may co-occur in contaminated aquatic environments. Therefore, we investigated the effects of Mn and Cr, and their mixtures, on a freshwater Chlorophyceae, Raphidocelis subcapitata, using a multiple endpoint approach. Regarding the single exposure of metals, Mn was 4 times more toxic (median inhibitory concentration at 72 h [IC5072 h ] = 4.02 ± 0.45 µM Mn) than Cr (IC5072 h = 16.42 ± 4.94 µM Cr) for microalgae, considering the effects on the relative growth rate. Moreover, this species was the most sensitive to Mn, according to the species sensitivity distribution curve. Overall, the tested metals did not lead to significant changes in reactive oxygen species production, cellular complexity, and cell relative size but significantly decreased the algal growth and the mean cell chlorophyll a (Chl a) fluorescence at the highest concentrations (3.64-14.56 µM of Mn and 15.36-19.2 µM of Cr). The decreased mean cell Chl a fluorescence indicates an impact on pigment synthesis, which may be related to the observed growth inhibition. In the mixture tests, the reference models concentration addition and independent action were used to analyze the data, and the independent action model was the best fit to describe our results. Therefore, the Mn and Cr mixture was noninteractive, showing additive effects. This is the first study to address the combined toxicity of Mn and Cr regarding freshwater Chlorophyceae. Environ Toxicol Chem 2022;41:1004-1015. © 2022 SETAC.


Assuntos
Clorofíceas , Poluentes Químicos da Água , Clorofíceas/fisiologia , Clorofila A , Cromo/toxicidade , Água Doce , Manganês/toxicidade , Metais/toxicidade , Poluentes Químicos da Água/análise
18.
J Adv Res ; 35: 129-140, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35024197

RESUMO

Introduction: Hexavalent chromium (Cr(VI)), one of the toxic heavy metals, poses a serious threat to human and animal health. Protein acetylation regulates the structure and function of most proteins in a variety of ways. However, the hepatotoxicity of Cr(VI) and whether it is related to deacetylation remains largely unknown. Objectives: We aimed to explore the link between the deacetylation of silent information regulator two ortholog 1 (Sirt1) and hepatotoxicity induced by Cr(VI) exposure, and to better clarify the biological mechanism of liver injury induced by Cr(VI). Methods: We established a model of liver injury of K2Cr2O7 by injecting rats intraperitoneally for 35 days continuously and adding resveratrol (Res) to further explore the link between deacetylation and hepatotoxicity. Results: The results revealed that Cr(VI) induced inflammatory response and apoptosis in hepatocytes. Furthermore, Cr(VI) reduced Sirt1 expression and inhibited the deacetylation of Sirt1 to downstream key transcription factors, including nuclear factor erythroid 2-related factor 2 (Nrf2), Forkhead box O3 (FOXO3), and nuclear factor-kappa B (NF-κB). Conversely, when Res was administered as an activator of Sirt1, the deacetylation of Sirt1 was enhanced, and inflammatory response and apoptosis were significantly alleviated. Conclusion: In summary, this work firstly demonstrates that Cr(VI) induces liver injury in rat by inhibiting the deacetylation of Sirt1, which is of positive significance for protecting the natural environment and animal health from chronic Cr poisoning.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Cromo , Animais , Apoptose , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Cromo/toxicidade , NF-kappa B , Ratos
19.
Environ Pollut ; 296: 118784, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34979171

RESUMO

The bioavailability of chromium (Cr) in soils is highly dependent on Cr fractions and soil physicochemical properties, but it is still unclear how the Cr fractions change in different soils. In this study, phytotoxicity to wheat root elongation was evaluated in different soils across China, and the kinetics of the biogeochemical processes of the added Cr(VI) were examined. After 105 days of soil Cr(VI) spiking, the added Cr(VI) causing 10% inhibition (EC10) of wheat root elongation varied greatly in soils (0.92-151.12 mg kg-1). The results of correlation analysis between EC10 and soil properties showed that the toxicity of Cr was affected by pH, organic matter (OM), clay, cation exchange capacity (CEC), and amorphous Fe oxides. Moreover, the correlation analysis showed that wheat root elongation was more sensitive to extracted Cr(VI) than Cr(III) after 105 days of incubation. A kinetic model was established to evaluate the redox and aging-activating reactions of Cr(VI)/(III) over 105 days. The correlation analysis between the soil properties and rate constants of the model showed that the pH, clay, and amorphous Fe/Al oxides might be the key factors controlling the aging and reduction processes of Cr(VI), and the OM and CEC might greatly affect the aging process of Cr(III). This modeling study is helpful in understanding which soil properties control the transformation and toxicity of Cr in soils.


Assuntos
Poluentes do Solo , Solo , Cromo/análise , Cromo/toxicidade , Oxirredução , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Triticum
20.
Bioresour Technol ; 346: 126665, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34990857

RESUMO

The purpose of this study was to evaluate the bioremediation potential of the microalga Scenedesmus quadricauda in removing hexavalent chromium (Cr (VI)) from synthetic wastewater, under autotrophic and heterotrophic conditions and different inoculum concentrations. In both cultivation modes, the highest inoculum density of 0.8 g L-1 led to the highest Cr (VI) removal efficiency. In addition, Cr (VI) stress was more severe in 10 ppm compared to 5 ppm, while heavy metal effects were alleviated under heterotrophic conditions. Concurrently, Cr (VI) stress affected biomass quality, resulting in an increase in lipid and carbohydrate production and decreased proteins. Furthermore, under higher Cr (VI) concentration more saturated and monounsaturated fatty acids were produced, while monounsaturated fatty acids content was also greater under heterotrophic conditions. In total, the findings of this study highlight the advantages of heterotrophic cultivation of microalgae for concomitant industrial wastewater treatment and biofuel production.


Assuntos
Microalgas , Scenedesmus , Biodegradação Ambiental , Biocombustíveis , Biomassa , Cromo/toxicidade
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