RESUMEN

The pathophysiological effects of chronic heavy metal exposures on human health remains uncertain. In this study, we developed a novel chronic, low-dose exposure of Cadmium (CLEC) model using the hepatocellular cell lines, HepG2 and HUH7. We modulated cell culture conditions to mimic human normoglycemic (5.6 mM) and hyperglycemic (15 mM) states with concomitant cadmium (Cd) exposures for 24 weeks. CLEC cells undergo non-trivial alterations in glucose signaling and metabolic characteristics within our model. We observe elevated baseline reactive oxygen species (ROS) production and decreased 2-NBDG uptake indicative of glucose metabolic dysfunction. Additionally, induction of metallothionein (MT) expression, increased activation of Akt signaling (via phosphorylation) and reduced IRS-2 protein expression are observed in CLEC cells. Cell line specific changes are observed with HepG2 showing a much higher MT gene induction compared to HUH7 cell line which impacts glucose metabolic dysfunction. Hyperglycemic culture conditions (representing type II diabetes) significantly modulate CLEC effects on cells. In conclusion, pathophysiologically relevant models of chronic heavy metal exposures are urgently needed to gain an in-depth, mechanistic understanding of the long-term impacts of toxic metals (e.g., Cd) on human metabolic health.

Asunto(s)

Cadmio , Hiperglucemia , Insulina , Transducción de Señal , Humanos , Transducción de Señal/efectos de los fármacos , Insulina/metabolismo , Hiperglucemia/inducido químicamente , Hiperglucemia/metabolismo , Cadmio/toxicidad , Células Hep G2 , Especies Reactivas de Oxígeno/metabolismo , Metalotioneína/metabolismo , Metalotioneína/genética , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Relación Dosis-Respuesta a Droga , Glucosa/metabolismo , Proteínas Sustrato del Receptor de Insulina/metabolismo , Proteínas Sustrato del Receptor de Insulina/genética

RESUMEN

Antimony (Sb) poses a significant ecological threat. This study combines biochemical, pathological, transcriptome, and metabolome analyses to assess the short-term (14-day) toxic impact of two Sb levels (25 mg/kg and 125 mg/kg) on earthworms (Eisenia fetida). Higher Sb concentration caused severe intestinal damage, elevated metallothionein (MT) levels, and reduced antioxidant capacity. Metabolome analysis identifies 404 and 1698 significantly differential metabolites in the two groups. Metabolites such as S(-)-cathinone, N-phenyl-1-naphthylamine, serotonin, 4-hydroxymandelonitrile, and 5-fluoropentylindole contributed to the metabolic responses to Sb stress. Transcriptome analysis shows increased chitin synthesis as a protective response, impacting amino sugar and nucleotide sugar metabolism for cell wall synthesis and damage repair. Integrated analysis indicated that 5 metabolite-gene pairs were found in two Sb levels and 11 enriched pathways were related to signal transduction, carbohydrate metabolism, immune system, amino acid metabolism, digestive system, and nervous system. Therefore, the integration of multiomics approaches enhanced our comprehension of the molecular mechanisms underlying the toxicity of Sb in E. fetida.

Asunto(s)

Antimonio , Metaboloma , Oligoquetos , Contaminantes del Suelo , Transcriptoma , Animales , Oligoquetos/efectos de los fármacos , Oligoquetos/genética , Antimonio/toxicidad , Metaboloma/efectos de los fármacos , Transcriptoma/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Metalotioneína/genética , Metalotioneína/metabolismo

RESUMEN

The insufficient antioxidant reserves in tumor cells play a critical role in reactive oxygen species (ROS)-mediated therapeutics. Metallothionein-2 (MT-2), an intracellular cysteine-rich protein renowned for its potent antioxidant properties, is intricately involved in tumor development and correlates with a poor prognosis. Consequently, MT-2 emerges as a promising target for tumor therapy. Herein, we present the development of copper-doped carbon dots (Cu-CDs) to target MT-2 to compromise the delicate antioxidant reserves in tumor cells. These Cu-CDs with high tumor accumulation and prolonged body retention can effectively suppress tumor growth by inducing oxidative stress. Transcriptome sequencing unveils a significant decrease in MT-2 expression within the in vivo tumor samples. Further mechanical investigations demonstrate that the antitumor effect of Cu-CDs is intricately linked to apolipoprotein E (ApoE)-mediated downregulation of MT-2 expression and the collapse of the antioxidant system. The robust antitumor efficacy of Cu-CDs provides invaluable insights into developing MT-2-targeted nanomedicine for cancer therapies.

Asunto(s)

Antioxidantes , Carbono , Cobre , Metalotioneína , Puntos Cuánticos , Metalotioneína/genética , Metalotioneína/metabolismo , Cobre/química , Cobre/farmacología , Carbono/química , Carbono/farmacología , Humanos , Animales , Ratones , Antioxidantes/farmacología , Antioxidantes/química , Puntos Cuánticos/química , Puntos Cuánticos/uso terapéutico , Línea Celular Tumoral , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/química , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo

RESUMEN

The mechanisms underlying the selective regional vulnerability to neurodegeneration in Huntington's disease (HD) have not been fully defined. To explore the role of astrocytes in this phenomenon, we used single-nucleus and bulk RNAseq, lipidomics, HTT gene CAG repeat-length measurements, and multiplexed immunofluorescence on HD and control post-mortem brains. We identified genes that correlated with CAG repeat length, which were enriched in astrocyte genes, and lipidomic signatures that implicated poly-unsaturated fatty acids in sensitizing neurons to cell death. Because astrocytes play essential roles in lipid metabolism, we explored the heterogeneity of astrocytic states in both protoplasmic and fibrous-like (CD44+) astrocytes. Significantly, one protoplasmic astrocyte state showed high levels of metallothioneins and was correlated with the selective vulnerability of distinct striatal neuronal populations. When modeled in vitro, this state improved the viability of HD-patient-derived spiny projection neurons. Our findings uncover key roles of astrocytic states in protecting against neurodegeneration in HD.

Asunto(s)

Astrocitos , Enfermedad de Huntington , Neuronas , Enfermedad de Huntington/metabolismo , Enfermedad de Huntington/genética , Enfermedad de Huntington/patología , Astrocitos/metabolismo , Astrocitos/patología , Humanos , Neuronas/metabolismo , Proteína Huntingtina/genética , Proteína Huntingtina/metabolismo , Masculino , Femenino , Lipidómica/métodos , Persona de Mediana Edad , Metalotioneína/metabolismo , Metalotioneína/genética , Encéfalo/metabolismo , Encéfalo/patología , Metabolismo de los Lípidos , Anciano , Multiómica

RESUMEN

Idiopathic male infertility, a significant health concern, lacks a clear etiology. Cadmium (Cd), a widespread environmental pollutant known to impact male reproductive health negatively, can accumulate in mussels, a common food source in Egypt. This study investigated the link between ecological Cd exposure, oxidative stress, MT1A methylation, and idiopathic male infertility in two regions of Alexandria. Thirty-three infertile men and 33 fertile controls were included. Cd levels were measured in mussels from the study sites and in participants' blood and semen. Biomarkers reflecting Cd exposure and its effects were assessed. Mussel Cd levels exceeded regulatory limits. Infertile men revealed significantly higher blood and semen Cd levels, reduced semen quality, increased oxidative stress, and elevated MT1A methylation compared to controls. MT1A methylation was inversely correlated with sperm count and is the strongest predictor of idiopathic male infertility, demonstrating the lowest p-value and considerable effect size. This study suggests that environmental Cd exposure, potentially through mussel consumption, may contribute to idiopathic male infertility in Egypt by increasing oxidative stress, inducing epigenetic modifications, and impairing semen quality. These findings underscore the need for further research into the mechanisms underlying Cd-induced male infertility and the development of preventative strategies.

Asunto(s)

Cadmio , Infertilidad Masculina , Estrés Oxidativo , Masculino , Humanos , Cadmio/toxicidad , Egipto , Infertilidad Masculina/inducido químicamente , Estrés Oxidativo/efectos de los fármacos , Estudios de Casos y Controles , Adulto , Animales , Metilación , Análisis de Semen , Exposición a Riesgos Ambientales/efectos adversos , Metalotioneína/metabolismo , Metalotioneína/genética , Biomarcadores/sangre

RESUMEN

Cadmium is a heavy metal that pollutes the environment and foods and is a risk factor for vascular disorders. We have previously demonstrated that pretreatment of vascular endothelial cells with zinc and copper protects the cells against cadmium cytotoxicity. In contrast, cadmium cytotoxicity was potentiated in cells following exposure to lead, thereby indicating that in vascular endothelial cells, cadmium cytotoxicity can be differentially modified by the co-occurrence of other heavy metals. In this study, we revealed that simultaneous treatment or pretreatment with manganese protects vascular endothelial cells against cadmium cytotoxicity. Intracellular accumulation of cadmium was observed to be reduced by simultaneous treatment with manganese, although not by pretreatment. The mRNA expression of metal transporters that regulate the uptake of both cadmium and manganese (ZIP8, ZIP14, and DMT1) remained unaffected by either simultaneous treatment or pretreatment with manganese, and simultaneous treatment with manganese suppressed the cadmium-induced expression of metallothionein but pretreatment with manganese did not exhibit such suppressive effect. Thus, the protection of vascular endothelial cells against cadmium cytotoxicity conferred by simultaneous treatment with manganese is assumed to be partially attributed to a reduction in the intracellular accumulation of cadmium, whereas the effects of pretreatment with manganese are independent of both the reduced intracellular accumulation of cadmium and the induction of metallothionein. These observations accordingly indicate that the protective effects of manganese are mediated via alternative (as yet unidentified) mechanisms.

Asunto(s)

Células Endoteliales , Manganeso , Metalotioneína , Metalotioneína/metabolismo , Metalotioneína/genética , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Células Cultivadas , Manganeso/toxicidad , Cadmio/toxicidad , Proteínas de Transporte de Catión/genética , Proteínas de Transporte de Catión/metabolismo , ARN Mensajero/metabolismo , ARN Mensajero/genética , Humanos , Animales , Supervivencia Celular/efectos de los fármacos

RESUMEN

Thallium (Tl), though not essential for biological systems, is widely used in industrial activities, resulting in soil pollution and adverse effects on soil biota. Systematic toxicological studies on Tl, especially concerning soil organisms, are relatively rare. This research evaluates the toxic effects of Tl on earthworms by measuring oxidative stress biomarkers, such as superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), malondialdehyde (MDA), and 8-hydroxydeoxyguanosine (8-OHdG), and by assessing the expression of functional genes, such as heat shock protein 70 (Hsp70), metallothionein (MT), and annetocin (ANN). Additionally, this study employs the Biomarker Response Index (BRI) and two-way ANOVA to comprehensively assess the cumulative toxicity of Tl in earthworms. The findings indicate that Tl exposure significantly exacerbates oxidative stress and cellular damage in earthworms, particularly under conditions of high concentration and prolonged exposure. BRI results demonstrate a continuous decline in the physiological state of earthworms with increasing Tl concentration and exposure duration. Two-way ANOVA reveals significant dose-responsive increases in SOD and CAT activities, as well as in ANN gene expression. Apart from GST activity, other biomarkers significantly increased over time, and the changes in biomarkers such as SOD, CAT, MDA, and 8-OHdG were significantly influenced by dose and time. LSD post hoc tests show significant effects of dose, time, and their interactions on all biomarkers except for GST. These findings are valuable for gaining a deeper understanding of the ecological risks of Tl in soil environments and its potential threats to soil biota, aiding in the management of ecological risks associated with Tl-contaminated soils.

Asunto(s)

Biomarcadores , Oligoquetos , Estrés Oxidativo , Contaminantes del Suelo , Talio , Oligoquetos/efectos de los fármacos , Animales , Contaminantes del Suelo/toxicidad , Biomarcadores/metabolismo , Estrés Oxidativo/efectos de los fármacos , Talio/toxicidad , Glutatión Transferasa/metabolismo , Glutatión Transferasa/genética , Superóxido Dismutasa/metabolismo , Monitoreo del Ambiente/métodos , Malondialdehído/metabolismo , Metalotioneína/metabolismo , Metalotioneína/genética , Catalasa/metabolismo

RESUMEN

Contrast-induced acute kidney injury (CI-AKI) is a prevalent cause of renal dysfunction among hospitalized patients, yet the precise pathogenesis and effective therapeutic strategies remain elusive. In this study, we investigated the role of tubular ferroptosis in both experimental CI-AKI models and in primary tubular epithelial cells (PTECs) treated with ioversol. Using whole exome sequencing, we identified metallothioneins (MTs) as being among the most significantly downregulated genes following ioversol exposure. Our findings reveal that overexpression of Mt1 mitigates, whereas suppression of Mt-1 exacerbates, ioversol-induced tubular ferroptosis. Interestingly, the level of MTF1 (metal regulatory transcription factor 1), a principal regulator of Mt1, was found to increase in response to ioversol treatment. We further elucidated that ioversol activates LATS1 (Large tumor suppressor homolog 1), a kinase that promotes the phosphorylation and nuclear translocation of MTF1, thereby inhibiting its transcriptional activity for Mt1. Both genetic and pharmacological inhibition of LATS1 reversed the ioversol-induced suppression of Mt-1. From a therapeutic perspective, the LATS1 inhibitor TDI-011536, in combination with zinc acetate, was administered to a rodent model of CI-AKI. Our data indicate that this combination synergistically upregulates Mt1 expression and provides protection against contrast media-induced tubular ferroptosis. In summary, our study demonstrates that the reduction of Mt-1 contributes to tubular ferroptosis associated with CI-AKI. We show that contrast media activate LATS1, which in turn suppresses the transcriptional activity of MTF1 for Mt1. Herein, the combination of zinc acetate and a LATS1 inhibitor emerges as a potential therapeutic approach for the treatment of CI-AKI.

Asunto(s)

Lesión Renal Aguda , Ferroptosis , Metalotioneína , Proteínas Serina-Treonina Quinasas , Ferroptosis/efectos de los fármacos , Ferroptosis/genética , Metalotioneína/genética , Metalotioneína/metabolismo , Animales , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/patología , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/genética , Lesión Renal Aguda/tratamiento farmacológico , Ratones , Humanos , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Zinc/metabolismo , Medios de Contraste/efectos adversos , Masculino , Factor de Transcripción MTF-1 , Células Epiteliales/metabolismo , Células Epiteliales/efectos de los fármacos , Células Epiteliales/patología , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Sinergismo Farmacológico , Modelos Animales de Enfermedad , Túbulos Renales/patología , Túbulos Renales/metabolismo , Túbulos Renales/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos

RESUMEN

Bone homeostasis is maintained by an intricate balance between osteoclasts and osteoblasts, which becomes disturbed in osteoporosis. Metallothioneins (MTs) are major contributors in cellular zinc regulation. However, the role of MTs in bone cell regulation has remained unexplored. Single-cell RNA sequencing analysis discovered that, unlike the expression of other MT members, the expression of MT3 was unique to osteoclasts among various macrophage populations and was highly upregulated during osteoclast differentiation. This unique MT3 upregulation was validated experimentally and supported by ATAC sequencing data analyses. Downregulation of MT3 by gene knockdown or knockout resulted in excessive osteoclastogenesis and exacerbated bone loss in ovariectomy-induced osteoporosis. Transcriptome sequencing of MT3 knockdown osteoclasts and gene set enrichment analysis indicated that the oxidative stress and redox pathways were enriched, which was verified by MT3-dependent regulation of reactive oxygen species (ROS). In addition, MT3 deficiency increased the transcriptional activity of SP1 in a manner dependent on intracellular zinc levels. This MT3-zinc-SP1 axis was crucial for the control of osteoclasts, as zinc chelation and SP1 knockdown abrogated the promotion of SP1 activity and osteoclastogenesis by MT3 deletion. Moreover, SP1 bound to the NFATc1 promoter, and overexpression of an inactive SP1 mutant negated the effects of MT3 deletion on NFATc1 and osteoclastogenesis. In conclusion, MT3 plays a pivotal role in controlling osteoclastogenesis and bone metabolism via dual axes involving ROS and SP1. The present study demonstrated that MT3 elevation is a potential therapeutic strategy for osteolytic bone disorders, and it established for the first time that MT3 is a crucial bone mass regulator.

Asunto(s)

Metalotioneína 3 , Osteoclastos , Osteogénesis , Osteoporosis , Animales , Osteoporosis/metabolismo , Osteoporosis/genética , Osteoporosis/patología , Osteoporosis/etiología , Osteogénesis/genética , Ratones , Osteoclastos/metabolismo , Metalotioneína 3/metabolismo , Diferenciación Celular/genética , Femenino , Regulación de la Expresión Génica , Especies Reactivas de Oxígeno/metabolismo , Factor de Transcripción Sp1/metabolismo , Factor de Transcripción Sp1/genética , Zinc/metabolismo , Factores de Transcripción NFATC/metabolismo , Factores de Transcripción NFATC/genética , Metalotioneína/metabolismo , Metalotioneína/genética , Ratones Noqueados

RESUMEN

OBJECTIVE: To explore the expressions of zinc homeostasis-related proteins, G protein-coupled receptor 39 (GPR39) and ANO1 mRNA in the sperm of patients with asthenozoospermia (AS), and analyze their correlation with sperm motility. METHODS: We collected semen samples from 82 male subjects with PR+NP < 40%, PR < 32% and sperm concentration > 15×106/ml (the AS group, n = 40) or PR+NP ≥ 40%, PR ≥ 32% and sperm concentration > 15×106/ml (the normal control group, n = 42). We analyzed the routine semen parameters and measured the zinc content in the seminal plasma using the computer-assisted sperm analysis system, detected the expressions of zinc transporters (ZIP13, ZIP8 and ZNT10), metallothioneins (MT1G, MT1 and MTF), GPR39, and calcium-dependent chloride channel protein (ANO1) in the sperm by real-time quantitative PCR (RT qPCR), examined free zinc distribution in the sperm by laser confocal microscopy, and determined the expressions of GPR39 and MT1 proteins in the sperm by immunofluorescence staining, followed by Spearman rank correlation analysis of their correlation with semen parameters. RESULTS: There was no statistically significant difference in the zinc concentration in the seminal plasma between the AS and normal control groups (P>0.05). Compared with the controls, the AS patients showed a significantly reduced free zinc level (P<0.05), relative expressions of MT1G, MTF, ZIP13, GPR39 and ANO1 mRNA (P<0.05), and that of the GPR39 protein in the AS group (P<0.05). No statistically significant differences were observed in the relative expression levels of ZIP8, ZNT10 and MT1 mRNA between the two groups (P>0.05). The relative expression levels of GPR39, ANO1, MT1G and MTF mRNA were positively correlated with sperm motility and the percentage of progressively motile sperm (P<0.05). CONCLUSION: The expressions of zinc homeostasis proteins (MT1G, MTF and ZIP13), GPR39 and ANO1 mRNA are downregulated in the sperm of asthenozoospermia patients, and positively correlated with sperm motility.

Asunto(s)

Anoctamina-1 , Astenozoospermia , Proteínas de Transporte de Catión , ARN Mensajero , Receptores Acoplados a Proteínas G , Motilidad Espermática , Espermatozoides , Zinc , Humanos , Masculino , Astenozoospermia/metabolismo , Astenozoospermia/genética , Anoctamina-1/metabolismo , Anoctamina-1/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Zinc/metabolismo , Espermatozoides/metabolismo , Proteínas de Transporte de Catión/metabolismo , Proteínas de Transporte de Catión/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Metalotioneína/metabolismo , Metalotioneína/genética , Homeostasis , Adulto , Análisis de Semen , Relevancia Clínica , Proteínas de Neoplasias

RESUMEN

Within the intricate landscape of the proteome, approximately 30% of all proteins bind metal ions. This repertoire is even larger when considering all the different forms of a protein, known as proteoforms. Here, we propose the term "metalloforms" to refer to different structural or functional variations of a protein resulting from the binding of various hetero- or homogeneous metal ions. Using human Cu(I)/Zn(II)-metallothionein-3 as a representative model, we developed a chemical proteomics strategy to simultaneously differentiate and map Zn(II) and Cu(I) metal binding sites. In the first labeling step, N-ethylmaleimide reacts with Cysteine (Cys), resulting in the dissociation of all Zn(II) ions while Cu(I) remains bound to the protein. In the second labeling step, iodoacetamide is utilized to label Cu(I)-bound Cys residues. Native mass spectrometry (MS) was used to determine the metal/labeling protein stoichiometries, while bottom-up/top-down MS was used to map the Cys-labeled residues. Next, we used a developed methodology to interrogate an isolated rabbit liver metallothionein fraction containing three metallothionein-2 isoforms and multiple Cd(II)/Zn(II) metalloforms. The approach detailed in this study thus holds the potential to decode the metalloproteoform diversity within other proteins.

Asunto(s)

Cobre , Espectrometría de Masas , Metalotioneína , Proteómica , Zinc , Proteómica/métodos , Humanos , Zinc/metabolismo , Zinc/análisis , Zinc/química , Cobre/metabolismo , Cobre/química , Animales , Metalotioneína/química , Metalotioneína/metabolismo , Metalotioneína/análisis , Espectrometría de Masas/métodos , Sitios de Unión , Cisteína/metabolismo , Cisteína/química , Cisteína/análisis , Secuencia de Aminoácidos , Metalotioneína 3 , Isoformas de Proteínas/análisis , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/química , Conejos

RESUMEN

Metallothioneins (MTs) are non-enzymatic metal-binding proteins widely found in animals, plants, and microorganisms and are regulated by metal-responsive transcription factor 1 (MTF1). MT and MTF1 play crucial roles in detoxification, antioxidation, and anti-apoptosis. Therefore, they are key factors allowing organisms to endure the toxicity of heavy metal pollution. Phascolosoma esculenta is a marine invertebrate that inhabits intertidal zones and has a high tolerance to heavy metal stress. In this study, we cloned and identified MT and MTF1 genes from P. esculenta (designated as PeMT and PeMTF1). PeMT and PeMTF1 were widely expressed in all tissues and highly expressed in the intestine. When exposed to 16.8, 33.6, and 84 mg/L of zinc ions, the expression levels of PeMT and PeMTF1 in the intestine increased first and then decreased, peaking at 12 and 6 h, respectively, indicating that both PeMT and PeMTF1 rapidly responded to Zn stress. The recombinant pGEX-6p-1-MT protein enhanced the Zn tolerance of Escherichia coli and showed a dose-dependent ABTS free radical scavenging ability. After RNA interference (RNAi) with PeMT and 24 h of Zn stress, the oxidative stress indices (MDA content, SOD activity, and GSH content) and the apoptosis indices (Caspase 3, Caspase 8, and Caspase 9 activities) were significantly increased, implying that PeMT plays an important role in Zn detoxification, antioxidation, and anti-apoptosis. Moreover, the expression level of PeMT in the intestine was significantly decreased after RNAi with PeMTF1 and 24 h of Zn stress, which preliminarily proved that PeMTF1 has a regulatory effect on PeMT. Our data suggest that PeMT and PeMTF1 play important roles in the resistance of P. esculenta to Zn stress and are the key factors allowing P. esculenta to endure the toxicity of Zn.

Asunto(s)

Metalotioneína , Factores de Transcripción , Zinc , Metalotioneína/genética , Metalotioneína/metabolismo , Animales , Zinc/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Estrés Fisiológico/efectos de los fármacos , Estrés Fisiológico/genética , Factor de Transcripción MTF-1 , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Apoptosis/efectos de los fármacos , Filogenia , Secuencia de Aminoácidos , Regulación de la Expresión Génica/efectos de los fármacos , Clonación Molecular

RESUMEN

To analyze the mechanism of copper accumulation in the marine alga Ulva compressa, it was cultivated with 10 µM of copper, with 10 µM of copper and increasing concentrations of a sulfide donor (NaHS) for 0 to 7 days, and with 10 µM of copper and a concentration of the sulfide acceptor (hypotaurine) for 5 days. The level of intracellular copper was determined as well as the level of glutathione (GSH) and phytochelatins (PCs) and the expression of metallothioneins (UcMTs). The level of intracellular copper in the algae treated with copper increased at day 1, slightly increased until day 5 and remained unchanged until day 7. The level of copper in the algae cultivated with copper and 100 or 200 µM of NaHS continuously increased until day 7 and the copper level was higher in the algae cultivated with 200 µM of NaHS compared to 100 µM of NaHS. In contrast, the level of intracellular copper decreased in the algae treated with copper and hypotaurine. The level of intracellular copper did not correlate with the level of GSH or with the expression of UcMTs, and PCs were not detected in response to copper, or copper and NaHS. Algae treated with copper and with copper and 200 µM of NaHS for 5 days were visualized by TEM and the elemental composition of electrondense particles was analyzed by EDXS. The algae treated with copper showed electrondense particles containing copper and sulfur, but not nitrogen, and they were mainly located in the chloroplast, but also in the cytoplasm. The algae treated with copper and NaHS showed a higher level of electrondense particles containing copper and sulfur, but not nitrogen, and they were located in the chloroplast, and in the cytoplasm. Thus, copper is accumulated as copper sulfide insoluble particles, and not bound to GSH, PCs or UcMTs, in the marine alga U. compressa.

Asunto(s)

Cobre , Glutatión , Metalotioneína , Fitoquelatinas , Sulfuros , Ulva , Cobre/metabolismo , Ulva/metabolismo , Ulva/efectos de los fármacos , Fitoquelatinas/metabolismo , Glutatión/metabolismo , Metalotioneína/metabolismo , Sulfuros/metabolismo , Taurina/análogos & derivados

Asunto(s)

Dieta Cetogénica , Metalotioneína , Enfermedad del Hígado Graso no Alcohólico , Regulación hacia Arriba , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/prevención & control , Dieta Cetogénica/métodos , Metalotioneína/metabolismo , Humanos , Antioxidantes

RESUMEN

The accurate and sensitive detection of metallothionein (MT) is of great significance in the fields of biomedical, toxicological and environmental sciences. In this work, based on the high affinity interaction between MT and the heavy metal ions of Hg2+ and the significant signal amplification capability of Cas12a/crRNA enzyme as well, we report a simple and highly sensitive method for visual detection of MT, a biomarker in fish for heavy metal ion-induced water bio-pollution. The target MT molecules bind Hg2+ in the Hg2+- complexed hairpin DNA probes to unfold the hairpin structure into ssDNAs, which hybridize with the partial dsDNA duplexes via strand displacement to yield specific sequence-containing dsDNAs. Cas12a/crRNA recognizes these specific sequences to activate its enzyme activity to cyclically cleave the ssDNA linkers in the blue colored gold nanoparticle aggregates to transit their color into red to realize visual detection of MT. Owing to the signal amplification by Cas12a/crRNA, as low as 25 nM of MT can be visually detected with naked eye. In addition, our colorimetric detection method has high selectivity for MT against other interference proteins and can detect MT in the livers and kidneys of crucian carps bought from a local supermarket. Moreover, the developed assay overcomes the limitations of conventional MT detection methods in terms of complexity, high cost and low sensitivity and can therefore offer new methods for monitoring water bio-pollutions.

Asunto(s)

Colorimetría , Sondas de ADN , Peces , Oro , Nanopartículas del Metal , Metalotioneína , Colorimetría/métodos , Animales , Metalotioneína/metabolismo , Metalotioneína/genética , Oro/química , Nanopartículas del Metal/química , Sondas de ADN/química , Sondas de ADN/metabolismo , Sondas de ADN/genética , Peces/metabolismo , Mercurio/análisis , Sistemas CRISPR-Cas , Límite de Detección , Técnicas de Amplificación de Ácido Nucleico/métodos , Técnicas Biosensibles/métodos

RESUMEN

Sinopotamon Henanense expresses two metal‒induced metallothioneins (MTs), Cd‒induced MT and Cu‒induced MT (ShCuMT). The Cd‒induced MT has been characterized as a Cd‒thiolate MT. However, it is unknown whether ShCuMT is a Cu‒thiolate MT. In the present study, ShCuMT was expressed heterologously in Escherichia coli and purified by Ni‒NTA column and superdex‒75 column. And its metal‒binding feature was evaluated by DTNB reaction, circular dichroism spectroscopy (CD), isothermal microtitration (ITC), electrospray flight mass spectrometry (ESI‒TOF‒MS), and matrix‒assisted laser desorption ionization flight mass spectrometry (MALDI‒TOF‒MS). Bioinformatics analysis demonstrated that ShCuMT possessed the cysteine‒triplet motif of a Cu‒specific MT. Expression and purification of ShCuMT illustrated that SUMO tag used as the production system for ShCuMT resulted in a high production yield. The stability order of ShCuMT binding metal ions were Cu (Ⅰ) > Cd (Ⅱ) > Zn (Ⅱ). The CD spectrum indicated that ShCuMT binding with Cu (I) exhibited a compact thiol metal clusters structure. Besides, there emerged no a visible nickel‒thiol absorption after Ni‒NTA column affinity chromatography. The ITC results implied that Cu‒ShCuMT possessed the optimal thermodynamic conformation and the highest stoichiometric number of Cu (Ⅰ). Overall, the results suggested that SUMO fusion system is a robust and inexpensive approach for ShCuMT expression and Ni‒NTA column had no influence on metal binding of ShCuMT and Cu(Ⅰ) was considered its cognate metal ion, and ShCuMT possessed canonical Cu‒thiolate characteristics. The metal binding feature of ShCuMT reported here contributes to elucidating the structure‒function relationship of ShCuMT in S. Henanense.

Asunto(s)

Cobre , Metalotioneína , Metalotioneína/genética , Metalotioneína/química , Metalotioneína/metabolismo , Metalotioneína/aislamiento & purificación , Animales , Cobre/metabolismo , Cobre/química , Braquiuros/genética , Braquiuros/metabolismo , Braquiuros/química , Proteínas de Artrópodos/genética , Proteínas de Artrópodos/química , Proteínas de Artrópodos/metabolismo , Cadmio/metabolismo , Cadmio/química , Escherichia coli/genética , Escherichia coli/metabolismo , Secuencia de Aminoácidos , Unión Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/biosíntesis

RESUMEN

Abnormal proliferation of pulmonary artery smooth muscle cells (PASMCs) is one of the critical pathological mechanisms of pulmonary hypertension (PH), and therefore is gradually being adopted as an important direction for the treatment of PH. Metallothioneins (MTs) have been reported to be associated with PH, but the underlying mechanisms are not fully understood. Here, we demonstrated that the expression level of metallothionein 3 (MT3) was significantly increased in pulmonary arterioles from PH patients and chronic hypoxia-induced rat and mouse PH models, as well as in hypoxia-treated human PASMCs. Knockdown of MT3 significantly inhibited the proliferation of human PASMCs by arresting the cell cycle in the G1 phase, while overexpression of MT3 had the opposite effect. Mechanistically, we found that MT3 increased the intracellular zinc (Zn2+) concentration to enhance the transcriptional activity of metal-regulated transcription factor 1 (MTF1), which promoted the expression of autophagy-related gene 5 (ATG5), facilitating autophagosome formation. More importantly, MT3-induced autophagy and proliferation of human PASMCs were largely prevented by knockdown of MTF1 and ATG5. Therefore, in this study, we identified MT3-Zinc-MTF1-ATG5 as a novel pathway that affects PASMC proliferation by regulating autophagosome formation, suggesting that MT3 may be a novel target for the treatment of PH.

Asunto(s)

Proliferación Celular , Metalotioneína 3 , Miocitos del Músculo Liso , Arteria Pulmonar , Zinc , Arteria Pulmonar/citología , Arteria Pulmonar/metabolismo , Animales , Humanos , Zinc/metabolismo , Ratones , Ratas , Miocitos del Músculo Liso/metabolismo , Masculino , Autofagosomas/metabolismo , Proteína 5 Relacionada con la Autofagia/metabolismo , Proteína 5 Relacionada con la Autofagia/genética , Ratas Sprague-Dawley , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Autofagia , Hipertensión Pulmonar/metabolismo , Ratones Endogámicos C57BL , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Factor de Transcripción MTF-1 , Metalotioneína/metabolismo , Metalotioneína/genética

RESUMEN

The contamination of water by arsenic (As) has emerged as a significant environmental concern due to its well-documented toxicity. Environmentally relevant concentrations of As have been reported to pose a considerable threat to fish. However, previous studies mainly focused on the impacts of As at environmentally relevant concentrations on adult fish, and limited information is available regarding its impacts on fish at early life stage. In this study, zebrafish embryos were employed to evaluate the environmental risks following exposure to different concentrations (0, 25, 50, 75 and 150 µg/L) of pentavalent arsenate (AsV) for 120 hours post fertilization. Our findings indicated that concentrations ≤ 150 µg/L AsV did not exert significant effects on survival or aberration; however, it conspicuously inhibited heart rate of zebrafish larvae. Furthermore, exposure to AsV significantly disrupted mRNA transcription of genes associated with cardiac development, and elongated the distance between the sinus venosus and bulbus arteriosus at 75 µg/L and 150 µg/L treatments. Additionally, AsV exposure enhanced superoxide dismutase (SOD) activity at 50, 75 and 150 µg/L treatments, and increased mRNA transcriptional levels of Cu/ZnSOD and MnSOD at 75 and 150 µg/L treatments. Concurrently, AsV suppressed metallothionein1 (MT1) and MT2 mRNA transcriptions while elevating heat shock protein70 mRNA transcription levels in zebrafish larvae resulting in elevated malondialdehyde (MDA) levels. These findings provide novel insights into the toxic effects exerted by low concentrations of AsV on fish at early life stage, thereby contributing to an exploration into the environmental risks associated with environmentally relevant concentrations.

Asunto(s)

Arseniatos , Embrión no Mamífero , Corazón , Estrés Oxidativo , Contaminantes Químicos del Agua , Pez Cebra , Animales , Arseniatos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Estrés Oxidativo/efectos de los fármacos , Embrión no Mamífero/efectos de los fármacos , Corazón/efectos de los fármacos , Superóxido Dismutasa/metabolismo , Metalotioneína/metabolismo , Metalotioneína/genética , Larva/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Relación Dosis-Respuesta a Droga

RESUMEN

Bioremediation of cadmium (Cd) pollution, a recognized low-carbon green environmental protection technology, is significantly enhanced by the discovery of Cd-tolerant microorganisms and their underlying tolerance mechanisms. This study presents Colpoda sp., a soil ciliate with widespread distribution, as a novel bioindicator and bioremediator for Cd contamination. With a 24 h-LC50 of 5.39 mg l-1 and an IC50 of 24.85 µg l-1 in Cd-contaminated water, Colpoda sp. achieves a maximum bioaccumulation factor (BAF) of 3.58 and a Cd removal rate of 32.98 ± 0.74 % within 96 h. The toxic responses of Colpoda sp. to Cd stress were assessed through cytological observation with transmission electron microscopy (TEM), oxidative stress kinase activity, and analysis of Cd-metallothionein (Cd-MTs) and the cd-mt gene via qRT-PCR. The integrated biomarker response index version 2 (IBRv2) and structural equation models (SEM) were utilized to analyze key factors and mechanisms, revealing that the up-regulation of Cd-MTs and cd-mt expression, rather than the oxidative stress system, is the primary determinant of Cd accumulation and tolerance in Colpoda sp. The ciliate's ability to maintain growth under 24.85 µg l-1 Cd stress and its capacity to absorb and accumulate Cd particles from water into cells are pivotal for bioremediation. A new mathematical formula and regression equations based on Colpoda sp.'s response parameters have been established to evaluate environmental Cd removal levels and design remediation schemes for contaminated sites. These findings provide a novel bioremediation and monitoring pathway for Cd remobilization and accumulation in soil and water, potentially revolutionizing the governance of Cd pollution.

Asunto(s)

Biodegradación Ambiental , Cadmio , Cilióforos , Metalotioneína , Contaminantes del Suelo , Cadmio/toxicidad , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/metabolismo , Cilióforos/efectos de los fármacos , Cilióforos/metabolismo , Metalotioneína/metabolismo , Estrés Oxidativo/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad

RESUMEN

Zinc (Zn) is the second most abundant metal in the human body and is essential for the function of 10% of all proteins. As metals cannot be synthesized or degraded, they must be assimilated from the diet by specialized transport proteins, which unfortunately also provide an entry route for the toxic metal pollutant cadmium (Cd). The intestinal absorption of Zn depends on the composition of food that is consumed, firstly the amount of Zn itself and then the quantity of other food constituents such as phytate, protein, and calcium (Ca). In cells, Zn is involved in the regulation of intermediary metabolism, gene expression, cell growth, differentiation, apoptosis, and antioxidant defense mechanisms. The cellular influx, efflux, subcellular compartmentalization, and trafficking of Zn are coordinated by transporter proteins, solute-linked carriers 30A and 39A (SLC30A and SLC39A), known as the ZnT and Zrt/Irt-like protein (ZIP). Because of its chemical similarity with Zn and Ca, Cd disrupts the physiological functions of both. The concurrent induction of a Zn efflux transporter ZnT1 (SLC30A1) and metallothionein by Cd disrupts the homeostasis and reduces the bioavailability of Zn. The present review highlights the increased mortality and the severity of various diseases among Cd-exposed persons and the roles of Zn and other transport proteins in the manifestation of Cd cytotoxicity. Special emphasis is given to Zn intake levels that may lower the risk of vision loss and bone fracture associated with Cd exposure. The difficult challenge of determining a permissible intake level of Cd is discussed in relation to the recommended dietary Zn intake levels.

Asunto(s)

Cadmio , Zinc , Humanos , Cadmio/toxicidad , Cadmio/metabolismo , Zinc/metabolismo , Exposición a Riesgos Ambientales/efectos adversos , Animales , Proteínas de Transporte de Catión/metabolismo , Proteínas de Transporte de Catión/genética , Metalotioneína/metabolismo