Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 164
Filtrar
1.
Nature ; 626(7998): 401-410, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38297129

RESUMO

Ferroptosis is a form of cell death that has received considerable attention not only as a means to eradicate defined tumour entities but also because it provides unforeseen insights into the metabolic adaptation that tumours exploit to counteract phospholipid oxidation1,2. Here, we identify proferroptotic activity of 7-dehydrocholesterol reductase (DHCR7) and an unexpected prosurvival function of its substrate, 7-dehydrocholesterol (7-DHC). Although previous studies suggested that high concentrations of 7-DHC are cytotoxic to developing neurons by favouring lipid peroxidation3, we now show that 7-DHC accumulation confers a robust prosurvival function in cancer cells. Because of its far superior reactivity towards peroxyl radicals, 7-DHC effectively shields (phospho)lipids from autoxidation and subsequent fragmentation. We provide validation in neuroblastoma and Burkitt's lymphoma xenografts where we demonstrate that the accumulation of 7-DHC is capable of inducing a shift towards a ferroptosis-resistant state in these tumours ultimately resulting in a more aggressive phenotype. Conclusively, our findings provide compelling evidence of a yet-unrecognized antiferroptotic activity of 7-DHC as a cell-intrinsic mechanism that could be exploited by cancer cells to escape ferroptosis.


Assuntos
Linfoma de Burkitt , Desidrocolesteróis , Ferroptose , Neuroblastoma , Animais , Humanos , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patologia , Sobrevivência Celular , Desidrocolesteróis/metabolismo , Peroxidação de Lipídeos , Transplante de Neoplasias , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Oxirredução , Fenótipo , Reprodutibilidade dos Testes
2.
EMBO J ; 40(10): e106214, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-33932034

RESUMO

BNIP3 is a mitophagy receptor with context-dependent roles in cancer, but whether and how it modulates melanoma growth in vivo remains unknown. Here, we found that elevated BNIP3 levels correlated with poorer melanoma patient's survival and depletion of BNIP3 in B16-F10 melanoma cells compromised tumor growth in vivo. BNIP3 depletion halted mitophagy and enforced a PHD2-mediated downregulation of HIF-1α and its glycolytic program both in vitro and in vivo. Mechanistically, we found that BNIP3-deprived melanoma cells displayed increased intracellular iron levels caused by heightened NCOA4-mediated ferritinophagy, which fostered PHD2-mediated HIF-1α destabilization. These effects were not phenocopied by ATG5 or NIX silencing. Restoring HIF-1α levels in BNIP3-depleted melanoma cells rescued their metabolic phenotype and tumor growth in vivo, but did not affect NCOA4 turnover, underscoring that these BNIP3 effects are not secondary to HIF-1α. These results unravel an unexpected role of BNIP3 as upstream regulator of the pro-tumorigenic HIF-1α glycolytic program in melanoma cells.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Melanoma/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais/metabolismo , Animais , Apoptose/genética , Apoptose/fisiologia , Linhagem Celular Tumoral , Biologia Computacional , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Immunoblotting , Imuno-Histoquímica , Espectroscopia de Ressonância Magnética , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
3.
Gastroenterology ; 165(1): 187-200.e7, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36966941

RESUMO

BACKGROUND & AIMS: Excess copper causes hepatocyte death in hereditary Wilson's disease (WD). Current WD treatments by copper-binding chelators may gradually reduce copper overload; they fail, however, to bring hepatic copper close to normal physiological levels. Consequently, lifelong daily dose regimens are required to hinder disease progression. This may result in severe issues due to nonadherence or unwanted adverse drug reactions and also due to drug switching and ultimate treatment failures. This study comparatively tested bacteria-derived copper binding agents-methanobactins (MBs)-for efficient liver copper depletion in WD rats as well as their safety and effect duration. METHODS: Copper chelators were tested in vitro and in vivo in WD rats. Metabolic cage housing allowed the accurate assessment of animal copper balances and long-term experiments related to the determination of minimal treatment phases. RESULTS: We found that copper-binding ARBM101 (previously known as MB-SB2) depletes WD rat liver copper dose dependently via fecal excretion down to normal physiological levels within 8 days, superseding the need for continuous treatment. Consequently, we developed a new treatment consisting of repetitive cycles, each of ∼1 week of ARBM101 applications, followed by months of in-between treatment pauses to ensure a healthy long-term survival in WD rats. CONCLUSIONS: ARBM101 safely and efficiently depletes excess liver copper from WD rats, thus allowing for short treatment periods as well as prolonged in-between rest periods.


Assuntos
Degeneração Hepatolenticular , Ratos , Animais , Degeneração Hepatolenticular/tratamento farmacológico , Degeneração Hepatolenticular/metabolismo , Cobre , Eliminação Hepatobiliar , Fígado/metabolismo , Quelantes/farmacologia , Quelantes/uso terapêutico
4.
Acta Neuropathol ; 147(1): 106, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38907771

RESUMO

We show that redox active iron can induce a regulated form of non-apoptotic cell death and tissue damage called ferroptosis that can contribute to secondary damage and functional loss in the acute and chronic periods after spinal cord injury (SCI) in young, adult, female mice. Phagocytosis of red blood cells at sites of hemorrhage is the main source of iron derived from hemoglobin after SCI. Expression of hemeoxygenase-1 that induces release of iron from heme, is increased in spinal cord macrophages 7 days after injury. While iron is stored safely in ferritin in the injured spinal cord, it can, however, be released by NCOA4-mediated shuttling of ferritin to autophagosomes for degradation (ferritinophagy). This leads to the release of redox active iron that can cause free radical damage. Expression of NCOA4 is increased after SCI, mainly in macrophages. Increase in the ratio of redox active ferrous (Fe2+) to ferric iron (Fe3+) is also detected after SCI by capillary electrophoresis inductively coupled mass spectrometry. These changes are accompanied by other hallmarks of ferroptosis, i.e., deficiency in various elements of the antioxidant glutathione (GSH) pathway. We also detect increases in enzymes that repair membrane lipids (ACSL4 and LPCAT3) and thus promote on-going ferroptosis. These changes are associated with increased levels of 4-hydroxynonenal (4-HNE), a toxic lipid peroxidation product. Mice with mild SCI (30 kdyne force) treated with the ferroptosis inhibitor (UAMC-3203-HCL) either early or delayed times after injury showed improvement in locomotor recovery and secondary damage. Cerebrospinal fluid and serum samples from human SCI cases show evidence of increased iron storage (ferritin), and other iron related molecules, and reduction in GSH. Collectively, these data suggest that ferroptosis contributes to secondary damage after SCI and highlights the possible use of ferroptosis inhibitors to treat SCI.


Assuntos
Ferroptose , Traumatismos da Medula Espinal , Ferroptose/efeitos dos fármacos , Ferroptose/fisiologia , Animais , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/tratamento farmacológico , Camundongos , Feminino , Camundongos Endogâmicos C57BL , Ferro/metabolismo , Atraso no Tratamento
5.
Proc Natl Acad Sci U S A ; 118(28)2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34260395

RESUMO

Novel MRI techniques allow a noninvasive quantification of tissue sodium and reveal the skin as a prominent compartment of sodium storage in health and disease. Since multiple sclerosis (MS) immunopathology is initiated in the periphery and increased sodium concentrations induce proinflammatory immune cells, the skin represents a promising compartment linking high sodium concentrations and MS immunopathology. We used a 7-T sodium MRI (23Na-MRI) and inductively coupled plasma mass spectrometry to investigate the skin sodium content in two mouse models of MS. We additionally performed 3-T 23Na-MRI of calf skin and muscles in 29 male relapsing-remitting MS (RRMS) patients and 29 matched healthy controls. Demographic and clinical information was collected from interviews, and disease activity was assessed by expanded disability status scale scoring. 23Na-MRI and chemical analysis demonstrated a significantly increased sodium content in the skin during experimental autoimmune encephalomyelitis independent of active immunization. In male patients with RRMS, 23Na-MRI demonstrated a higher sodium signal in the area of the skin compared to age- and biological sex-matched healthy controls with higher sodium, predicting future disease activity in cranial MRI. In both studies, the sodium enrichment was specific to the skin, as we found no alterations of sodium signals in the muscle or other tissues. Our data add to the recently identified importance of the skin as a storage compartment of sodium and may further represent an important organ for future investigations on salt as a proinflammatory agent driving autoimmune neuroinflammation such as that in MS.


Assuntos
Esclerose Múltipla/metabolismo , Pele/metabolismo , Sódio/metabolismo , Adulto , Animais , Modelos Animais de Doenças , Humanos , Inflamação/patologia , Imageamento por Ressonância Magnética , Masculino , Camundongos Endogâmicos C57BL , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla Recidivante-Remitente/metabolismo , Processamento de Sinais Assistido por Computador , Pele/diagnóstico por imagem
6.
J Proteome Res ; 22(3): 837-850, 2023 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-36594972

RESUMO

Parkinson's disease (PD) progresses with the loss of dopaminergic neurons in the substantia nigra pars compacta region of the brain. The superior mechanisms and the cause of this specific localized neurodegeneration is currently unknown. However, experimental evidence indicates a link between PD progression and reactive oxygen species with imbalanced metal homeostasis. Wild-type Caenorhabditis elegans exposed to redox-active metals was used as the model organism to study cellular response to imbalanced metal homeostasis linked to neurodegenerative diseases. Using modern hyphenated techniques such as capillary electrophoresis coupled to inductively coupled plasma mass spectrometry and ultrahigh-performance liquid chromatography mass spectrometry, alterations in the lipidome and metallome were determined in vivo. In contrast to iron, most of the absorbed zinc and manganese were loosely bound. We observed changes in the phospholipid composition for acute iron and manganese exposures, as well as chronic zinc exposure. Furthermore, we focused on the mitochondrial membrane alteration due to its importance in neuronal function. However, significant changes in the inner mitochondrial membrane by determination of cardiolipin species could only be observed for acute iron exposure. These results indicate different intracellular sites of local ROS generation, depending on the redox active metal. Our study combines metallomic and lipidomic alterations as the cause and consequence to enlighten intracellular mechanisms in vivo, associated with PD progression. The mass spectrometry raw data have been deposited to the MassIVE database (https://massive.ucsd.edu) with the identifier MSV000090796 and 10.25345/C51J97C8F.


Assuntos
Doenças Neurodegenerativas , Doença de Parkinson , Animais , Ferro/metabolismo , Manganês/metabolismo , Caenorhabditis elegans/genética , Zinco , Lipidômica , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/metabolismo , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Metais , Neurônios Dopaminérgicos/metabolismo
7.
Environ Sci Technol ; 57(14): 5532-5543, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-36976662

RESUMO

Residential heating with solid fuels is one of the major drivers for poor air quality in Central and Eastern Europe, and coal is still one of the major fuels in countries, such as Poland, the Czech Republic, and Hungary. In this work, emissions from a single-room heater fueled with brown coal briquettes (BCBs) and spruce logs (SLs) were analyzed for signatures of inorganic as well as semivolatile aromatic and low-volatile organic constituents. High variations in organic carbon (OC) emissions of BCB emissions, ranging from 5 to 22 mg MJ-1, were associated to variations in carbon monoxide (CO) emissions, ranging from 900 to 1900 mg MJ-1. Residential BCB combustion turned out to be an equally important source of levoglucosan, an established biomass burning marker, as spruce logwood combustion, but showed distinct higher ratios to manosan and galactosan. Signatures of polycyclic aromatic hydrocarbons emitted by BCB combustion exhibited defunctionalization and desubstitution with increasing combustion quality. Lastly, the concept of island and archipelago structural motifs adapted from petroleomics is used to describe the fraction low-volatile organic compounds in particulate emissions, where a transition from archipelago to island motifs in relation with decreasing CO emissions was observed in BCB emissions, while emissions from SL combustion exhibited the island motif.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Material Particulado/análise , Poluentes Atmosféricos/análise , Carvão Mineral/análise , Calefação , Aerossóis
8.
Int J Mol Sci ; 24(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36902319

RESUMO

It is with great pleasure that we introduce this Special Issue on "Homeostasis: Metals and Cellular Redox and Immunity Status" [...].


Assuntos
Metais , Oxirredução , Homeostase
9.
FASEB J ; 35(7): e21721, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34118090

RESUMO

Mineral homeostasis is regulated by a complex network involving endocrine actions by calcitriol, parathyroid hormone (PTH), and FGF23 on several organs including kidney, intestine, and bone. Alterations of mineral homeostasis are found in chronic kidney disease and other systemic disorders. The interplay between the immune system and the skeletal system is not fully understood, but cytokines play a major role in modulating calcitriol production and function. One of the main cellular signaling pathways mediating cytokine function is the Janus kinase (JAK)--signal transducer and activator of transcription (STAT) pathway. Here, we used a mouse model (Jak1S645P+/- ) that resembles a constitutive activating mutation of the Jak1/Stat3 signaling pathway in humans, and shows altered mineral metabolism, with higher fibroblast growth factor 23 (FGF23) levels, lower PTH levels, and higher calcitriol levels. The higher calcitriol levels are probably due to extrarenal calcitriol production. Furthermore, systemic Jak1/Stat3 activation led to growth impairment and skeletal alterations. The growth plate in long bones showed decreased chondrocyte proliferation rates and reduced height of terminal chondrocytes. Furthermore, we demonstrate that Jak1 is also involved in bone remodeling early in life. Jak1S645P+/- animals have decreased bone and cortical volume, imbalanced bone remodeling, reduced MAP kinase signaling, and local inflammation. In conclusion, Jak1 plays a major role in bone health probably both, directly and systemically by regulating mineral homeostasis. Understanding the role of this signaling pathway will contribute to a better knowledge in bone growth and in mineral physiology, and to the development of selective Jak inhibitors as osteoprotective agents.


Assuntos
Osso e Ossos/metabolismo , Osso e Ossos/fisiologia , Calcitriol/metabolismo , Transtornos do Crescimento/metabolismo , Janus Quinase 1/metabolismo , Transdução de Sinais/fisiologia , Animais , Remodelação Óssea/fisiologia , Proliferação de Células/fisiologia , Condrócitos/metabolismo , Condrócitos/fisiologia , Citocinas/metabolismo , Feminino , Fator de Crescimento de Fibroblastos 23 , Fatores de Crescimento de Fibroblastos , Lâmina de Crescimento/metabolismo , Lâmina de Crescimento/fisiologia , Homeostase/fisiologia , Humanos , Inflamação/metabolismo , Rim/metabolismo , Rim/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Mutação/genética , Hormônio Paratireóideo/metabolismo , Fator de Transcrição STAT3/metabolismo
10.
Int J Mol Sci ; 23(11)2022 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-35682788

RESUMO

Element analysis in clinical or biological samples is important due to the essential role in clinical diagnostics, drug development, and drug-effect monitoring. Particularly, the specific forms of element binding, actual redox state, or their spatial distribution in tissue or in single cells are of interest in medical research. This review summarized exciting combinations of sophisticated sample delivery systems hyphenated to inductively coupled plasma-mass spectrometry (ICP-MS), enabling a broadening of information beyond the well-established outstanding detection capability. Deeper insights into pathological disease processes or intracellular distribution of active substances were provided, enabling a better understanding of biological processes and their dynamics. Examples were presented from spatial elemental mapping in tissue, cells, or spheroids, also considering elemental tagging. The use of natural or artificial tags for drug monitoring was shown. In the context of oxidative stress and ferroptosis iron, redox speciation gained importance. Quantification methods for Fe2+, Fe3+, and ferritin-bound iron were introduced. In Wilson's disease, free and exchangeable copper play decisive roles; the respective paragraph provided information about hyphenated Cu speciation techniques, which provide their fast and reliable quantification. Finally, single cell ICP-MS provides highly valuable information on cell-to-cell variance, insights into uptake of metal-containing drugs, and their accumulation and release on the single-cell level.


Assuntos
Degeneração Hepatolenticular , Oligoelementos , Humanos , Ferro , Espectrometria de Massas/métodos , Metais/análise , Preparações Farmacêuticas , Oligoelementos/análise
11.
Int J Mol Sci ; 23(13)2022 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-35806114

RESUMO

Antibiotic-resistant bacteria pose one of the major threats to human health worldwide. The issue is fundamental in the case of chronic wound treatment. One of the latest trends to overcome the problem is the search for new antibacterial agents based on silver. Thus, the aim of this research was to synthesize the silver-lactoferrin complex as a new generation of substances for the treatment of infected wounds. Moreover, one of the tasks was to investigate the formation mechanisms of the respective complexes and the influence of different synthesis conditions on the features of final product. The batch-sorption study was performed by applying the Langmuir and Freundlich isotherm models for the process description. Characterization of the complexes was carried out by spectroscopy, spectrometry, and separation techniques, as well as with electron microscopy. Additionally, the biological properties of the complex were evaluated, i.e., the antibacterial activity against selected bacteria and the impact on L929 cell-line viability. The results indicate the formation of a heterogeneous silver-lactoferrin complex that comprises silver nanoparticles. The complex has higher antibacterial strength than both native bovine lactoferrin and Ag+, while being comparable to silver toxicity.


Assuntos
Nanopartículas Metálicas , Prata , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias , Fenômenos Químicos , Humanos , Lactoferrina/farmacologia , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Prata/química , Prata/farmacologia
12.
Klin Monbl Augenheilkd ; 239(3): 326-330, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33607688

RESUMO

BACKGROUND: Trace elements are assumed to be involved in glaucoma pathogenesis via changes in oxidative stress. Especially serum selenium (Se) has been linked to this neurodegenerative disease. Serum Se levels differ between countries due to nutrition and ethnicity. It was the aim of the present study to investigate serum Se levels in primary open-angle glaucoma (POAG) patients and controls in Germany and to consider potential age and gender effects. MATERIAL AND METHODS: The Se concentration of 39 serum samples (22 patients with POAG, 17 controls) were analyzed by inductively coupled plasma-sector field mass spectrometry (ICP-sf-MS) in high resolution mode. Covariance and percentile regression were analyzed. Age and gender were defined as confounding factors and their different trends were investigated. Moreover, age was examined across different quantiles of Se levels. RESULTS: Total serum least-squares means (LS-means) Se levels were 132.02 µg/L (controls) and 134.86 µg/L (POAG). Total serum Se levels did not differ between the study groups (p > 0.05). Significant age and gender effects of serum Se were observed. Quantile analysis showed that the 1st serum Se quantile decreased with increasing age in POAG patients in contrast to controls. The odds ratios of the 1st serum Se were 1.3 (with 2nd quantile) and 1.3 (with 3rd quantile), respectively. CONCLUSION: The serum Se level of the German cohort was almost half of those of the published US cohort (glaucoma 209.11 ng/mL; control 194.45 ng/mL). Age and gender effects were observed; the serum Se level increased with age in women (controls and POAG), however, Se levels decreased with age in men (controls and POAG).


Assuntos
Glaucoma de Ângulo Aberto , Doenças Neurodegenerativas , Selênio , Oligoelementos , Feminino , Glaucoma de Ângulo Aberto/diagnóstico , Humanos , Masculino , Projetos Piloto
13.
Mov Disord ; 36(12): 2967-2969, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34553776

RESUMO

Longitudinal PD CSF samples were subjected to ICP-MS and the total amount of iron and other bioelements was quantified. Additionally, ferritin and protein biomarkers of neurodegeneration were measured. Over time, mean iron levels significantly increased while levels of ferritin decreased.


Assuntos
Ferritinas , Ferro , Doença de Parkinson , Biomarcadores/líquido cefalorraquidiano , Ferritinas/líquido cefalorraquidiano , Humanos , Ferro/líquido cefalorraquidiano , Doença de Parkinson/líquido cefalorraquidiano , Doença de Parkinson/diagnóstico
14.
Biometals ; 34(4): 923-936, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34003408

RESUMO

The objective of the present study was to investigate the impact of iron deficiency and iron replenishment on serum iron (Fe), copper (Cu), manganese (Mn), and zinc (Zn) speciation and tissue accumulation in a deferrioxamine-induced model of iron deficiency. A total of 26 male Wistar rats were divided into three groups: control; Fe-deficient; Fe-replenished (with iron (II) gluconate). Serum ferritin and transferrin levels were assessed using immunoturbudimetric method. Liver, spleen, and serum metal levels were assessed using ICP-MS. Speciation analysis was performed using a hyphenated HPLC-ICP-MS technique. Desferrioxamine injections resulted in a significant decrease in tissue iron content that was reversed by Fe supplementation. Iron speciation revealed a significant increase in serum transferrin-bound iron and reduced ferritin-bound Fe levels. Serum but not tissue Cu levels were characterized by a significant decrease in hypoferremic rats, whereas ceruloplasmin-bound fraction tended to increase. At the same time, Zn levels were found to be higher in liver, spleen, and serum of Fe-deficient rats with a predominant increase in low molecular weight fraction.Both iron-deficient and iron-replenished rats were characteirzed by increased transferrin-bound Mn levels and reduced low-molecular weight fraction. Hypothetically, these differences may be associated with impaired Fe metabolism under Fe-deficient conditions predisposing to impairment of essential metal handling. However, further studies aimed at assessment of the impact on Fe deficiency on metal metabolism are highly required.


Assuntos
Cobre/metabolismo , Deficiências de Ferro/metabolismo , Ferro/metabolismo , Manganês/metabolismo , Zinco/metabolismo , Animais , Desferroxamina , Deficiências de Ferro/induzido quimicamente , Masculino , Ratos , Ratos Wistar
15.
Int J Mol Sci ; 22(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34445607

RESUMO

BACKGROUND: Transition metals play a crucial role in brain metabolism: since they exist in different oxidation states they are involved in ROS generation, but they are also co-factors of enzymes in cellular energy metabolism or oxidative defense. METHODS: Paired serum and cerebrospinal fluid (CSF) samples were analyzed for iron, zinc, copper and manganese as well as for speciation using SEC-ICP-DRC-MS. Brain extracts from Mn-exposed rats were additionally analyzed with SEC-ICP-DRC-MS. RESULTS: The concentration patterns of transition metal size fractions were correlated between serum and CSF: Total element concentrations were significantly lower in CSF. Fe-ferritin was decreased in CSF whereas a LMW Fe fraction was relatively increased. The 400-600 kDa Zn fraction and the Cu-ceruloplasmin fraction were decreased in CSF, by contrast the 40-80 kDa fraction, containing Cu- and Zn-albumin, relatively increased. For manganese, the α-2-macroglobulin fraction showed significantly lower concentration in CSF, whereas the citrate Mn fraction was enriched. Results from the rat brain extracts supported the findings from human paired serum and CSF samples. CONCLUSIONS: Transition metals are strictly controlled at neural barriers (NB) of neurologic healthy patients. High molecular weight species are down-concentrated along NB, however, the Mn-citrate fraction seems to be less controlled, which may be problematic under environmental load.


Assuntos
Encéfalo/metabolismo , Cromatografia em Gel/métodos , Espectrometria de Massas/métodos , Oligoelementos/sangue , Oligoelementos/líquido cefalorraquidiano , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ratos
16.
Neurobiol Dis ; 134: 104677, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31733347

RESUMO

The aim of the study was to validate a predictive biomarker machine learning model for the classification of Parkinson's disease (PD) and age-matched controls (AMC), based on bioelement abundance in the cerebrospinal fluid (CSF). For this multicentric trial, participants were enrolled from four different centers. CSF was collected according to standardized protocols. For bioelement determination, CSF samples were subjected to inductively coupled plasma mass spectrometry. A predefined Support Vector Machine (SVM) model, trained on a previous discovery cohort was applied for differentiation, based on the levels of six different bioelements. 82 PD patients, 68 age-matched controls and 7 additional Normal Pressure Hydrocephalus (NPH) patients were included to validate a predefined SVM model. Six differentiating elements (As, Fe, Mg, Ni, Se, Sr) were quantified. Based on their levels, SVM was successfully applied to a new local cohort (AUROC 0.76, Sensitivity 0.80, Specificity 0.83), without taking any additional features into account. The same model did not discriminate PD and AMCs / NPH from three external cohorts, likely due to center effects. However, discrimination was possible in cohorts with a full elemental data set, now using center-specific discovery cohorts and a cross validated approach (AUROC 0.78 and 0.88, respectively). Pooled PD CSF iron levels showed a clear correlation with disease duration (p = .0001). In summary, bioelemental CSF patterns, obtained by mass spectrometry and integrated into a predictive model yield the potential to facilitate the differentiation of PD and AMC. Center-specific biases interfere with application in external cohorts. This must be carefully addressed using center-defined, local reference values and models.


Assuntos
Doença de Parkinson/líquido cefalorraquidiano , Doença de Parkinson/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/líquido cefalorraquidiano , Feminino , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Máquina de Vetores de Suporte
17.
Coord Chem Rev ; 4172020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32905350

RESUMO

The present study addresses existing data on the affinity and conjugation of sulfhydryl (thiol; -SH) groups of low- and high-molecular-weight biological ligands with mercury (Hg). The consequences of these interactions with special emphasis on pathways of Hg toxicity are highlighted. Cysteine (Cys) is considered the primary target of Hg, and link its sensitivity with thiol groups and cellular damage. In vivo, Hg complexes play a key role in Hg metabolism. Due to the increased affinity of Hg to SH groups in Cys residues, glutathione (GSH) is reactive. The geometry of Hg(II) glutathionates is less understood than that with Cys. Both Cys and GSH Hg-conjugates are important in Hg transport. The binding of Hg to Cys mediates multiple toxic effects of Hg, especially inhibitory effects on enzymes and other proteins that contain free Cys residues. In blood plasma, albumin is the main Hg-binding (Hg2+, CH3Hg+, C2H5Hg+, C6H5Hg+) protein. At the Cys34 residue, Hg2+ binds to albumin, whereas other metals likely are bound at the N-terminal site and multi-metal binding sites. In addition to albumin, Hg binds to multiple Cys-containing enzymes (including manganese-superoxide dismutase (Mn-SOD), arginase I, sorbitol dehydrogenase, and δ-aminolevulinate dehydratase, etc.) involved in multiple processes. The affinity of Hg for thiol groups may also underlie the pathways of Hg toxicity. In particular, Hg-SH may contribute to apoptosis modulation by interfering with Akt/CREB, Keap1/Nrf2, NF-κB, and mitochondrial pathways. Mercury-induced oxidative stress may ensue from Cys-Hg binding and inhibition of Mn-SOD (Cys196), thioredoxin reductase (TrxR) (Cys497) activity, as well as limiting GSH (GS-HgCH3) and Trx (Cys32, 35, 62, 65, 73) availability. Moreover, Hg-thiol interaction also is crucial in the neurotoxicity of Hg by modulating the cytoskeleton and neuronal receptors, to name a few. However, existing data on the role of Hg-SH binding in the Hg toxicity remains poorly defined. Therefore, more research is needed to understand better the role of Hg-thiol binding in the molecular pathways of Hg toxicology and the critical role of thiols to counteract negative effects of Hg overload.

18.
Neuroepidemiology ; 54(1): 1-23, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31454800

RESUMO

BACKGROUND: Parkinson's disease (PD) is the most common neurodegenerative disease after Alzheimer's dementia. Whereas the exact etiology of PD remains unknown, risk of developing PD seems to be related to a combination of genetic and environmental factors. This also includes abnormal exposure to trace elements of nutritional and toxicological interest. OBJECTIVES: In this systematic review and meta-analysis, we summarized the results of case-control studies comparing levels of selenium, copper, iron, and zinc in PD patients and controls in either blood (whole blood, serum/plasma) or cerebrospinal fluid (CSF). METHODS: We performed a systematic PubMed search selecting studies reporting trace element levels in different specimens of patients and controls. We performed a meta-analysis using a random-effect model to compute the weighted mean differences (WMD) and corresponding 95% CI of selenium, copper, iron, and zinc levels in the blood or CSF of patients and their matched controls. RESULTS: We retrieved 56 papers reporting data for selenium (cases/controls: 588/721), copper (2,190/2,522), iron (2,956/3,469), and zinc (1,798/1,913) contents in CSF and blood. Cases showed considerably higher levels of selenium in CSF compared with controls (+51.6%; WMD 5.49; 95% CI 2.82 to 8.15), while levels in serum were similar (-0.2%; WMD -0.22; 95% CI -8.05 to 7.62). For copper, cases showed slightly higher levels in CSF and slightly lower concentrations in serum (+4.5%; WMD 1.87; 95% CI -3.59 to 7.33, and -4.5%; WMD -42.79; 95% CI -134.35 to 48.76, respectively). A slight increase was also found for CSF iron -levels (+9.5%; WMD 9.92; 1.23 to 18.61), while levels were -decreased in serum/plasma (-5.7%; WMD -58.19; 95% CI -106.49 to -9.89) and whole blood (-10.8%; WMD -95.69; 95% CI -157.73 to -33.65). Conversely, for zinc cases exhibited lower levels both in CSF (-10.8%; WMD -7.34; 95% CI -14.82 to 0.14) and serum/plasma (-7.5%; WMD -79.93; 95% CI -143.80 to -16.06). A longer duration of the disease tends to be associated with overall lower trace element levels in either CSF or blood. CONCLUSIONS: Due to the study findings and the greater relevance of the CSF compartment compared with the circulating peripheral ones, this meta-analysis suggests that overexposure in the central nervous system to selenium, and possibly to copper and iron, may be a risk factor of the disease, while zinc might have a protective -effect.


Assuntos
Doença de Parkinson/etiologia , Selênio , Oligoelementos , Estudos de Casos e Controles , Humanos , Selênio/efeitos adversos , Selênio/sangue , Selênio/líquido cefalorraquidiano , Oligoelementos/efeitos adversos , Oligoelementos/sangue , Oligoelementos/líquido cefalorraquidiano
19.
Biometals ; 33(1): 65-74, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31811450

RESUMO

This study aims at the assessment of total zinc contents, water zinc extract contents and zinc-protein profile in medicinal plants traditionally used for diabetes treatment. While zinc-protein profile was screened in plant samples using the online coupling of size exclusion chromatography-inductively coupled plasma-mass spectrometry (SEC-ICP-MS), total zinc contents and zinc water extract contents were determined using inductively coupled plasma-optical emission spectrometry (ICP-OES). The analysis of two certified reference materials with similar matrix for total zinc content revealed recovery values of 97.1% and 100.5% while the average of recovery of the summed Zn concentrations from protein fractions compared to total Zn was 103.0 ± 4.8%. Based on the FAO/WHO classification, Sesamum indicum, Nigella sativa, Trigonella Foenum-graecum and Pennisetum glaucum are classified as highest Zn-content. For protein profile, zinc was quantified in 330-430 and 50-60 kDa fractions of all examined plants while no contents were quantified in the inorganic fraction 0.05-0.4 kDa of all plant species. Also, only three plant species recorded Zn contents in the phytate fraction (0.9-1.5 kDa fraction). The fruits of the Momordica Charantia and the Citrullus colocynthis were with the highest extractable zinc concentration; 13.55 ± 0.45 and 10.08 ± 0.63 mg/kg, respectively. The highest Zinc capturing capacity was reported for the 50-60 and 70-87 KDa protein fractions.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Proteínas de Plantas/química , Plantas Medicinais/química , Zinco/análise , Humanos , Análise Espectral
20.
Part Fibre Toxicol ; 17(1): 27, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32539833

RESUMO

BACKGROUND: Wood combustion emissions have been studied previously either by in vitro or in vivo models using collected particles, yet most studies have neglected gaseous compounds. Furthermore, a more accurate and holistic view of the toxicity of aerosols can be gained with parallel in vitro and in vivo studies using direct exposure methods. Moreover, modern exposure techniques such as air-liquid interface (ALI) exposures enable better assessment of the toxicity of the applied aerosols than, for example, the previous state-of-the-art submerged cell exposure techniques. METHODS: We used three different ALI exposure systems in parallel to study the toxicological effects of spruce and pine combustion emissions in human alveolar epithelial (A549) and murine macrophage (RAW264.7) cell lines. A whole-body mouse inhalation system was also used to expose C57BL/6 J mice to aerosol emissions. Moreover, gaseous and particulate fractions were studied separately in one of the cell exposure systems. After exposure, the cells and animals were measured for various parameters of cytotoxicity, inflammation, genotoxicity, transcriptome and proteome. RESULTS: We found that diluted (1:15) exposure pine combustion emissions (PM1 mass 7.7 ± 6.5 mg m- 3, 41 mg MJ- 1) contained, on average, more PM and polycyclic aromatic hydrocarbons (PAHs) than spruce (PM1 mass 4.3 ± 5.1 mg m- 3, 26 mg MJ- 1) emissions, which instead showed a higher concentration of inorganic metals in the emission aerosol. Both A549 cells and mice exposed to these emissions showed low levels of inflammation but significantly increased genotoxicity. Gaseous emission compounds produced similar genotoxicity and a higher inflammatory response than the corresponding complete combustion emission in A549 cells. Systems biology approaches supported the findings, but we detected differing responses between in vivo and in vitro experiments. CONCLUSIONS: Comprehensive in vitro and in vivo exposure studies with emission characterization and systems biology approaches revealed further information on the effects of combustion aerosol toxicity than could be achieved with either method alone. Interestingly, in vitro and in vivo exposures showed the opposite order of the highest DNA damage. In vitro measurements also indicated that the gaseous fraction of emission aerosols may be more important in causing adverse toxicological effects. Combustion aerosols of different wood species result in mild but aerosol specific in vitro and in vivo effects.


Assuntos
Poluentes Atmosféricos/toxicidade , Dano ao DNA , Exposição por Inalação/efeitos adversos , Picea/química , Pinus/química , Fumaça/efeitos adversos , Madeira , Células A549 , Aerossóis , Poluentes Atmosféricos/análise , Animais , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Calefação , Humanos , Exposição por Inalação/análise , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Tamanho da Partícula , Células RAW 264.7 , Fumaça/análise , Especificidade da Espécie , Transcriptoma/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA