RESUMO
Patients poisoned with drugs and nonpharmaceutical substances are frequently admitted from the emergency department (ED) to a medical or ICU department. We hypothesized that biomarkers of inflammation and inflammation-related indexes based on the complete blood cell (CBC) count can identify acutely poisoned patients at increased risk for ICU hospitalization and death. We performed a 6-year prospective cohort study on 1548 adult patients. The demographic data, the levels of hs-CRP (high-sensitivity C-reactive protein), CBC, and inflammation-related indexes based on CBC counts were collected upon admission and compared between survivors and nonsurvivors, based on the poison involved. Both a multivariate logistic regression model with only significant univariate predictors and a model including univariate predictors plus each log-transformed inflammation-related indexes for mortality were constructed. The importance of the variables for mortality was graphically represented using the nomogram. hs-CRP (odds ratio (OR), 1.38; 95% CI, 1.16-1.65, p < 0.001 for log-transformed hs-CRP), red cell distribution width (RDW), neutrophil-lymphocyte ratio (NLR), and platelet-lymphocyte ratio (PLR) were significantly associated with the risk of ICU hospitalization, after multivariable adjustment. Only RDW, NLR, and monocyte-lymphocyte ratio (MLR) were significantly associated with mortality. The predictive accuracy for mortality of the models which included either NLR (AUC 0.917, 95% CI 0.886-0.948) or MLR (AUC 0.916, 95% CI 0.884-0.948) showed a high ability for prognostic detection. The use of hs-CRP, RDW, NLR, and MLR upon ED admission are promising screening tools for predicting the outcomes of patients acutely intoxicated with undifferentiated poisons.
Assuntos
Biomarcadores/análise , Serviço Hospitalar de Emergência/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Inflamação/diagnóstico , Unidades de Terapia Intensiva/estatística & dados numéricos , Intoxicação/mortalidade , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Plaquetas/patologia , Proteína C-Reativa/metabolismo , Índices de Eritrócitos , Feminino , Seguimentos , Humanos , Inflamação/complicações , Inflamação/imunologia , Inflamação/metabolismo , Linfócitos/patologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/patologia , Intoxicação/etiologia , Intoxicação/metabolismo , Intoxicação/patologia , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida , Adulto JovemRESUMO
The inhibition of acetylcholinesterase is regarded as the primary toxic mechanism of action for chemical warfare agents. Recently, there have been numerous reports suggesting that metabolic processes could significantly contribute to toxicity. As such, we applied a multi-omics pipeline to generate a detailed cascade of molecular events temporally occurring in guinea pigs exposed to VX. Proteomic and metabolomic profiling resulted in the identification of several enzymes and metabolic precursors involved in glycolysis and the TCA cycle. All lines of experimental evidence indicated that there was a blockade of the TCA cycle at isocitrate dehydrogenase 2, which converts isocitrate to α-ketoglutarate. Using a primary beating cardiomyocyte cell model, we were able to determine that the supplementation of α-ketoglutarate subsequently rescued cells from the acute effects of VX poisoning. This study highlights the broad impacts that VX has and how understanding these mechanisms could result in new therapeutics such as α-ketoglutarate.
Assuntos
Acetilcolinesterase/metabolismo , Agentes Neurotóxicos/toxicidade , Intoxicação/tratamento farmacológico , Proteoma/efeitos dos fármacos , Animais , Substâncias para a Guerra Química/toxicidade , Cobaias , Redes e Vias Metabólicas , Metabolômica , Intoxicação/metabolismo , ProteômicaRESUMO
Poisoning is the greatest source of avoidable death in the world and can result from industrial exhausts, incessant bush burning, drug overdose, accidental toxication or snake envenomation. Since the advent of Albert Calmette's cobra venom antidote, efforts have been geared towards antidotes development for various poisons to date. While there are resources and facilities to tackle poisoning in urban areas, rural areas and developing countries are challenged with poisoning management due to either the absence of or inadequate facilities and this has paved the way for phyto-antidotes, some of which have been scientifically validated. This review presents the scope of antidotes' effectiveness in different experimental models and biotechnological advancements in antidote research for future applications. While pockets of evidence of the effectiveness of antidotes exist in vitro and in vivo with ample biotechnological developments, the utilization of analytic assays on existing and newly developed antidotes that have surpassed the proof of concept stage, as well as the inclusion of antidote's short and long-term risk assessment report, will help in providing the required scientific evidence(s) prior to regulatory authorities' approval.
Assuntos
Antídotos/administração & dosagem , Intoxicação/tratamento farmacológico , Animais , Antídotos/efeitos adversos , Antídotos/química , Antídotos/farmacologia , Biotecnologia , Modelos Animais de Doenças , Desenvolvimento de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Humanos , Compostos Fitoquímicos/administração & dosagem , Compostos Fitoquímicos/química , Intoxicação/etiologia , Intoxicação/metabolismo , Resultado do TratamentoRESUMO
Death by mechanical asphyxia is one of the most difficult conclusions to make in forensic science, especially in corpses displaying slight or no trauma to the surface of the body. Therefore, death by mechanical asphyxia is difficult to prove in medico-legal practice. MicroRNAs (miRNAs) are a class of small, non-coding RNAs involved in the regulation of numerous physiological and pathological cellular processes. In the present study, we demonstrate that significantly increased expression of miR-3185 in cardiac tissues was detected among cases of mechanical asphyxia compared to case of craniocerebral injury, hemorrhagic shock, sudden cardiac death and poisoning. We observed no correlation between the expression of miR-3185 and postmortem interval, age or temperature. Further work indicated that CYP4A11 is a putative target gene of miR-3185 and expressed at a relatively low level in cardiac tissue specimens from cases of mechanical asphyxia compared with specimens from cases of craniocerebral injury, hemorrhagic shock, sudden cardiac death and poisoning. Our results suggest that the miRNA-3185/CYP4A11 axis is associated with mechanical asphyxia-induced death and may provide new insight into asphyxial death investigations.
Assuntos
Asfixia/diagnóstico , Citocromo P-450 CYP4A/metabolismo , MicroRNAs/metabolismo , Miocárdio/metabolismo , RNA Mensageiro/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Criança , Pré-Escolar , Traumatismos Craniocerebrais/metabolismo , Citocromo P-450 CYP4A/genética , Morte Súbita Cardíaca , Feminino , Genética Forense , Patologia Legal , Humanos , Masculino , Pessoa de Meia-Idade , Intoxicação/metabolismo , Mudanças Depois da Morte , Reação em Cadeia da Polimerase em Tempo Real , Choque Hemorrágico/metabolismo , Adulto JovemRESUMO
Acute intoxications account for a significant proportion of the patient population in intensive care units and sedative medications, ethanol, illicit drugs, inhalable poisons and mixed intoxications are the most common causes. The aim of this article is to describe biomarkers for screening and diagnosis of acute intoxications in critically ill patients. For this purpose, a survey of the relevant literature was conducted, and guidelines, case reports, expert assessments, and scientific publications were reviewed. In critical care, it should always be attempted to identify and quantify the poison or toxin with the assistance of enzyme immunoassay (EIA), chromatography, and mass spectrometry techniques and this section is critically appraised in this publication. The principles for anion gap, osmol gap and lactate gap and their usage in intoxications is shown. Basic rules in test methodology and pre-analytics are reviewed. Biomarkers in general are presented in part one and biomarkers for specific intoxications including ethanol, paracetamol, cardiovascular drugs and many others are presented in part two of these publications.
Assuntos
Biomarcadores/metabolismo , Overdose de Drogas/diagnóstico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Intoxicação/diagnóstico , Doença Aguda , Estado Terminal , Overdose de Drogas/epidemiologia , Overdose de Drogas/metabolismo , Overdose de Drogas/terapia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/metabolismo , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/terapia , Humanos , Intoxicação/epidemiologia , Intoxicação/metabolismo , Intoxicação/terapia , Valor Preditivo dos Testes , PrognósticoRESUMO
Peroxynitrite (ONOO-) is attracting increasing attention due to its involvement in multiple facets of pathophysiological processes. However, ONOO- bioimaging is still challenging due to (1) the lack of highly specific reaction triggers, (2) the tedious and low-yielding synthesis of current sophisticated probes, and (3) the lack of availability of a versatile chemical strategy. To address these challenges, on the basis of amine formylation/deformylation chemistry, we have developed a novel strategy for ONOO- bioimaging. As proof of principle, we designed, synthesized, and evaluated four novel fluorescent probes equipped with the formamide functionality. Although they feature distinctly different fluorophore classes, all probes can be synthesized in one step in high yields and exhibit particularly specific, highly sensitive, and rapid responses to ONOO-. The bioimaging capability is well demonstrated by successfully visualizing ONOO- fluctuation in live cells and major organs of mice suffering from paraquat poisoning. The proposed strategy has proved to be a facile, versatile, and highly efficient methodology for ONOO- visualization, which will greatly facilitate ONOO- biochemistry and pathophysiology.
Assuntos
Corantes Fluorescentes/química , Formamidas/química , Ácido Peroxinitroso/análise , Animais , Linhagem Celular Tumoral , Corantes Fluorescentes/síntese química , Formamidas/síntese química , Camundongos , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Paraquat/intoxicação , Ácido Peroxinitroso/química , Ácido Peroxinitroso/metabolismo , Intoxicação/metabolismo , Estudo de Prova de ConceitoRESUMO
Diquat (1,1'-ethylene-2,2'-bipyridinium ion; DQ) is a nonselective quick-acting herbicide, which is used as contact and preharvest desiccant to control terrestrial and aquatic vegetation. Several cases of human poisoning were reported worldwide mainly due to intentional ingestion of the liquid formulations. Its toxic potential results from its ability to produce reactive oxygen and nitrogen species through redox cycling processes that can lead to oxidative stress and potentially cell death. Kidney is the main target organ due to DQ toxicokinetics and redox cycling. There is no antidote against DQ intoxications, and the efficacy of treatments currently applied is still unsatisfactory. The aim of this work was to review the most relevant human and experimental findings related to DQ, characterizing its chemistry, activity as herbicide, mechanisms of toxicity, consequences of poisoning, and potential therapeutic approaches taking into account previous experience in developing antidotes for paraquat, a more toxic bipyridinium herbicide.
Assuntos
Desfolhantes Químicos/intoxicação , Diquat/intoxicação , Estresse Oxidativo/efeitos dos fármacos , Intoxicação/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Desfolhantes Químicos/farmacocinética , Diquat/farmacocinética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Necrose , Intoxicação/diagnóstico , Intoxicação/metabolismo , Intoxicação/mortalidade , Medição de Risco , Toxicocinética , Resultado do Tratamento , Adulto JovemRESUMO
It is conservatively estimated that 5,000 deaths per year and 20,000 injuries in the USA are due to poisonings caused by chemical exposures (e.g., carbon monoxide, cyanide, hydrogen sulfide, phosphides) that are cellular inhibitors. These chemical agents result in mitochondrial inhibition resulting in cardiac arrest and/or shock. These cellular inhibitors have multi-organ effects, but cardiovascular collapse is the primary cause of death marked by hypotension, lactic acidosis, and cardiac arrest. The mitochondria play a central role in cellular metabolism where oxygen consumption through the electron transport system is tightly coupled to ATP production and regulated by metabolic demands. There has been increasing use of human blood cells such as peripheral blood mononuclear cells and platelets, as surrogate markers of mitochondrial function in organs due to acute care illnesses. We demonstrate the clinical applicability of measuring mitochondrial bioenergetic and dynamic function in blood cells obtained from patients with acute poisoning using carbon monoxide poisoning as an illustration of our technique. Our methods have potential application to guide therapy and gauge severity of disease in poisoning related to cellular inhibitors of public health concern.
Assuntos
Células Sanguíneas/metabolismo , Mitocôndrias/metabolismo , Intoxicação/sangue , Intoxicação/metabolismo , Adulto , Biomarcadores , Intoxicação por Monóxido de Carbono/sangue , Intoxicação por Monóxido de Carbono/metabolismo , Metabolismo Energético , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/ultraestrutura , Pesquisa Translacional BiomédicaRESUMO
Dichlorodiphenyltrichloroethane (DDT) is an insecticidal organochlorine pesticide with; known potential for neurotoxic effects in wildlife. The United States Environmental Protection Agency (US EPA) registration for this pesticide has been cancelled and there are currently no federally active products that contain this ingredient in the U.S. We present a case of a colony of big brown bats (E. Fuscus) found dead in the attic roost of an administrative building; in the city of Hamilton, Montana from unknown cause. DDT and its metabolites; dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD) were detected in bat tissues by gas chromatography/mass spectrometry (GC-MS) and quantified by gas chromatography tandem quadrupole mass spectrometry (GC-MS/MS). Concentrations of 4081â¯ppm DDT and 890â¯ppm DDE wet weight were found in the brain of one bat and are the highest reported concentrations in such a mortality event to date. This case emphasizes the importance of testing wildlife mortalities against a comprehensive panel of toxicologic agents including persistent organic pollutants in the absence of other more common disease threats.
Assuntos
Quirópteros/metabolismo , DDT/intoxicação , Monitoramento Ambiental/métodos , Inseticidas/intoxicação , Animais , Encéfalo/metabolismo , DDT/análise , Diclorodifenil Dicloroetileno/análise , Diclorodifenildicloroetano/análise , Cromatografia Gasosa-Espectrometria de Massas , Inseticidas/análise , Montana , Intoxicação/metabolismo , Intoxicação/veterinária , Espectrometria de Massas em TandemRESUMO
BACKGROUND Paraquat is a major cause of fatal poisoning after ingestion in many parts of Asia and the Pacific nations. However, optimal prognostic indicators to evaluate patient mortality have not been unequivocally established. Following acute paraquat poisoning, a number of amino acids (AA), are abnormally expressed in metabolic pathways. However, the alterations in AA metabolite levels after paraquat poisoning remain unknown in humans. MATERIAL AND METHODS In the present study, 40 patients were enrolled, of whom 16 survived and 24 died. A metabolomics approach was used to assess changes in AA metabolites in plasma and its potential prognostic value following paraquat poisoning. Mass spectrometry (MS) based on metabolite identification was conducted. RESULTS Twenty-five AA levels in plasma were abnormally expressed in non-survivor patients. Among them, creatinine, indolelactate, and 3-(4-hydroxyphenyl)lactate were found to be highly correlated with paraquat death prediction. It was noted that the intensity levels of these 3 AA metabolites in the non-survivor group were substantially higher than in the survivor group. Furthermore, we examined receiver operating characteristic (ROC) curves for clinical validation. ROC results showed that 3-(4-hydroxyphenyl)lactate had the highest AUC of 0.84, while indolelactate and creatinine had AUCs of 0.75 and 0.83, respectively, suggesting that they can be used to predict the clinical outcome (although this methodology is expensive to implement). CONCLUSIONS Metabolic profiling of AA levels could be a reliable tool to identify effective indicators for the early high precision prognosis of paraquat poisoning.
Assuntos
Aminoácidos/metabolismo , Metabolômica/métodos , Paraquat/intoxicação , Intoxicação/metabolismo , Intoxicação/mortalidade , Doença Aguda , Adulto , Creatinina/metabolismo , Demografia , Feminino , Humanos , Ácidos Indolacéticos/metabolismo , Ácido Láctico/metabolismo , Masculino , Metaboloma , Análise de Componente Principal , Sobreviventes , Adulto JovemRESUMO
Diagnosis, monitoring of the efficiency of detoxification, and estimating the prognosis of acute poisonings are important tasks in emergency toxicology. Comprehensive screening and quantification of relevant substances by gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-mass spectrometry (LC-MS) help in assessing the severity of most acute poisonings. Turnaround time for such analyses must be short enough to impact on clinical decisions. Therefore, a multi-analyte LC-MS/MS approach with a 5-minute gradient was developed and validated for 45 drugs and their active metabolites as a complement to an existing GC-MS approach using the same liquid-liquid extraction. The determination ranges were defined by quality control samples of low and high, representing concentrations from low therapeutic to highly toxic levels. To shorten the turnaround time, one-point calibration was used. Validation showed low matrix effects and ionization effects of co-eluting analytes thanks to APCI source as well as sufficient recoveries, precisions, and selectivities. For accuracy, 32 of the 45 compounds fulfilled the criteria for quantification in lower therapeutic and 41 in overdosed and toxic concentrations, considering limits of ±30% deviation. The reuse of the processed calibrator for a period of 30 days was possible for 32 compounds, showing sufficient stability at 8°C. In addition, analysis of authentic blood samples showed the applicability and yielded drug levels, which were comparable to those determined by fully validated therapeutic drug monitoring methods. In conclusion, the present approach in combination with the GC-MS approach should provide sufficient support for clinical assessment of the severity of poisonings with 68 compounds in an acceptable turnaround time.
Assuntos
Preparações Farmacêuticas/metabolismo , Intoxicação/diagnóstico , Intoxicação/metabolismo , Índice de Gravidade de Doença , Espectrometria de Massas em Tandem/normas , Calibragem/normas , Cromatografia Líquida/métodos , Cromatografia Líquida/normas , Overdose de Drogas/sangue , Overdose de Drogas/diagnóstico , Overdose de Drogas/metabolismo , Humanos , Preparações Farmacêuticas/sangue , Intoxicação/sangue , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodosRESUMO
Reported here is a new analytical multiclass method based on QuEChERS technique, which has proven to be effective in diagnosing fatal poisoning cases in animals. This method has been developed for the determination of analytes in liver samples comprising rodenticides, carbamate and organophosphorus pesticides, coccidiostats and mycotoxins. The procedure entails addition of acetonitrile and sodium acetate to 2 g of homogenized liver sample. The mixture was shaken intensively and centrifuged for phase separation, which was followed by an organic phase transfer into a tube containing sorbents (PSA and C18) and magnesium sulfate, then it was centrifuged, the supernatant was filtered and analyzed by liquid chromatography tandem mass spectrometry. A validation of the procedure was performed. Repeatability variation coefficients <15% have been achieved for most of the analyzed substances. Analytical conditions allowed for a successful separation of variety of poisons with the typical screening detection limit at ≤10 µg/kg levels. The method was used to investigate more than 100 animals poisoning incidents and proved that is useful to be used in animal forensic toxicology cases.
Assuntos
Toxicologia Forense/métodos , Fígado/química , Intoxicação/veterinária , Venenos/análise , Medicina Veterinária/métodos , Animais , Cromatografia Líquida/veterinária , Intoxicação/diagnóstico , Intoxicação/metabolismo , Reprodutibilidade dos Testes , Extração em Fase Sólida/veterinária , Espectrometria de Massas em Tandem/veterináriaRESUMO
The burden and morbidity of environmental nephrosis is increasing globally. Atrazine (ATR) and degradation products in the environment are considered key determinants of nephrosis. However, the lack of highly effective treatments for environmental nephrosis creates an urgent need to better understand the preventive strategies and mechanisms. This study aimed to highlight the mechanism of ATR-induced environmental nephrosis and the chemoprotective potential of lycopene (LYC) against the renal injury and nephrosis. Male mice were treated with LYC (5 mg/kg) and/or ATR (50 mg/kg or 200 mg/kg) by gavage administration for 21 days. Histopathological changes and biochemical function, cytochrome P450 enzymes system (CYP450s), nuclear xenobiotic receptors (NXRs) response and the transcription of CYP isoforms (CYPs) were detected. ATR exposure caused the changes of the histopathological and biochemical function, activated the NXR response and disturbed the CYP450s homeostasis. Supplementary LYC significantly prevented ATR-induced nephrotoxicity and alleviated the alternation of histopathological and biochemical function via modulating the CYP450s homeostasis and the NXR response. The results demonstrated AHR, CAR, PXR, PPAR (α, γ), CYP1, CYP2, CYP3 and CYP4 superfamily play a vital role in LYC-ATR interaction. Our findings provide new evidence that ATR exposure can cause the environmental nephrosis via inducing the kidney injury. Supplementary LYC showed significant chemoprotective potential against ATR-induced renal injury and environmental nephrosis via regulating the NXR response and the CYP450s homeostasis.
Assuntos
Antioxidantes/uso terapêutico , Atrazina/toxicidade , Carotenoides/uso terapêutico , Herbicidas/toxicidade , Nefrose/prevenção & controle , Intoxicação/fisiopatologia , Receptores de Esteroides/antagonistas & inibidores , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Animais , Animais não Endogâmicos , Atrazina/administração & dosagem , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Núcleo Celular/patologia , Receptor Constitutivo de Androstano , Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Herbicidas/administração & dosagem , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Rim/fisiopatologia , Licopeno , Masculino , Camundongos , Nefrose/etiologia , Intoxicação/metabolismo , Intoxicação/patologia , Receptor de Pregnano X , Análise de Componente Principal , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Esteroides/agonistas , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismoRESUMO
Deaths involved with environmental hazards and intoxication might present with minimal or nonspecific morphological features, which are insufficient to establish a diagnosis. The present study investigated the postmortem brain mRNA and immunohistochemical expressions of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), inducible nitric oxide synthase (iNOS) and nuclear factor erythroid-2-related factor-2 (Nrf2) in forensic cases. Relative mRNA quantification using Taqman real-time PCR assay demonstrated higher expression of IL-1ß, TNF-α and iNOS, and lower expression of Nrf2 in methamphetamine intoxication and hyperthermia cases, higher expression of iNOS in phenobarbital intoxication cases, and higher expression of Nrf2 in phenobarbital intoxication and hypothermia cases. Immunostaining results showed substantial inter-individual variations in each group, showing no evident differences in distribution or intensity. These findings suggest that different inflammatory and antioxidant responses were involved in deaths from different etiologies, and these markers may be useful for evaluating brain damage and responses.
Assuntos
Encéfalo/metabolismo , Interleucina-1beta/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Asfixia/metabolismo , Biomarcadores/metabolismo , Encéfalo/patologia , Causas de Morte , Feminino , Febre/metabolismo , Patologia Legal , Humanos , Hipotermia/metabolismo , Imuno-Histoquímica , Interleucina-1beta/genética , Masculino , Pessoa de Meia-Idade , Fator 2 Relacionado a NF-E2/genética , Óxido Nítrico Sintase Tipo II/genética , Intoxicação/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fator de Necrose Tumoral alfa/genética , Ferimentos e Lesões/metabolismo , Adulto JovemRESUMO
Aniline exposure is associated with toxicity to the spleen, however, early molecular events in aniline-induced cell cycle progression in the spleen remain unknown. MicroRNAs (miRNAs) have been implicated in tumor development by modulating key cell cycle regulators and controlling cell proliferation. This study was, therefore, undertaken on the expression of miRNAs, regulation of cyclins and cyclin-dependent kinases (CDKs) in an experimental condition that precedes a tumorigenic response. Male SD rats were treated with aniline (1 mmol/kg/day by gavage) for 7 days, and expression of miRNAs, cyclins and CDKs in rat spleens were analyzed. Microarray and/or qPCR analyses showed that aniline exposure led to significantly decreased miRNA expression of let-7a, miR-24, miR-34c, miR-100, miR-125b, and greatly increased miR-181a. The aberrant expression of miRNAs was associated with significantly increased protein expression of cyclins A, B1, D3 and E. Furthermore, remarkably enhanced expression of CDKs like CDK1, CDK2, CDK4, CDK6, especially p-CDK1 and p-CDK2 as well as alternations in the expression of pRB, p27, and CDC25A in the spleens of aniline-treated rats was also observed. The data suggest that aniline exposure leads to aberrant expression of miRNAs in the spleen which could be important in the regulation of cell cycle proteins. Our findings, thus, provide new insight into the role of miRNAs in cell cycle progression, which may contribute to aniline-induced tumorigenic response in the spleen.
Assuntos
Compostos de Anilina/toxicidade , Carcinógenos Ambientais/toxicidade , Ciclo Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , MicroRNAs/antagonistas & inibidores , Intoxicação/metabolismo , Baço/efeitos dos fármacos , Animais , Análise por Conglomerados , Quinases Ciclina-Dependentes/química , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/agonistas , Ciclinas/genética , Ciclinas/metabolismo , Indução Enzimática/efeitos dos fármacos , Perfilação da Expressão Gênica , Masculino , MicroRNAs/metabolismo , Intoxicação/patologia , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Baço/metabolismo , Baço/patologiaRESUMO
Heavy metals, such as arsenic, chromium, cadmium, nickel, mercury, and uranium are known to cause many human diseases and health complications after occupational or environmental exposure. Consequently, metals are environmental health concerns. This manuscript is an overview of the 9th Conference on Metal Toxicity and Carcinogenesis held in October 2016 in Lexington, Kentucky. Since 2000, this biennial meeting brings together experts in the field to discuss current and prospective research in an effort to advance research pertaining to metal toxicity and carcinogenesis. In this review we summarize the major topics discussed and provide insight regarding current research in the field and an account of the direction in which the field is progressing.
Assuntos
Carcinogênese/efeitos dos fármacos , Congressos como Assunto/tendências , Exposição Ambiental/efeitos adversos , Intoxicação por Metais Pesados , Intoxicação , Animais , Carcinogênese/imunologia , Carcinogênese/metabolismo , Humanos , Kentucky , Metais Pesados/imunologia , Metais Pesados/metabolismo , Intoxicação/imunologia , Intoxicação/metabolismoRESUMO
Zinc is an essential trace element that serves as a catalytic cofactor in metalloenzymes and a structural element in proteins involved in general metabolism and cellular defenses of pathogenic bacteria. Despite its importance, high zinc levels can impair cellular processes, inhibiting growth of many pathogenic bacteria, including the major respiratory pathogen Streptococcus pneumoniae. Zinc intoxication is prevented in S. pneumoniae by expression of the zinc exporter CzcD, whose expression is activated by the novel TetR-family transcriptional zinc-sensing regulator SczA. How zinc bioavailability triggers activation of SczA is unknown. It is shown here through functional studies in S. pneumoniae that an unannotated homodimeric TetR from S. agalactiae (PDB 3KKC) is the bona fide zinc efflux regulator SczA, and binds two zinc ions per protomer. Mutagenesis analysis reveals two metal binding sites, termed A and B, located on opposite sides of the SczA C-terminal regulatory domain. In vivo, the A- and B-site SczA mutant variants impact S. pneumoniae resistance to zinc toxicity and survival in infected macrophages. A model is proposed for S. pneumoniae SczA function in which both A- and B-sites were required for transcriptional activation of czcD expression, with the A-site serving as the evolutionarily conserved intracellular sensing site in SczAs.
Assuntos
Zinco/metabolismo , Zinco/fisiologia , Motivos de Aminoácidos/genética , Sequência de Aminoácidos , Proteínas de Bactérias/metabolismo , Disponibilidade Biológica , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Intoxicação por Metais Pesados , Metais Pesados/metabolismo , Intoxicação/genética , Intoxicação/metabolismo , Streptococcus agalactiae/metabolismo , Streptococcus pneumoniae/metabolismo , Resistência a TetraciclinaRESUMO
Cadmium (Cd) is a highly toxic heavy metal and has spread widely in the environment in recent decades. This review summarizes current knowledge about Cd contamination of leafy vegetables, its toxicity, exposure, health risks, and approaches to reducing its toxicity in humans. Leafy vegetable consumption has been identified as a dominant exposure pathway of Cd in the human body. An overview of Cd pollution in leafy vegetables as well as the main sources of Cd is given. Notable estimated daily intakes and health risks of Cd exposure through vegetable consumption for humans are revealed in occupational exposure areas and even in some reference areas. Vegetable consumption is one of the most significant sources of exposure to Cd, particularly in occupational exposure regions. Therefore, numerous approaches have been developed to minimize the accumulation of Cd in leafy vegetables, among which the breeding of Cd pollution-safe cultivars is one of the most effective tools. Furthermore, dietary supplements from leafy vegetables perform positive roles in alleviating Cd toxicity in humans with regard to the effects of essential mineral elements, vitamins and phytochemicals taken into the human body via leafy vegetable consumption.
Assuntos
Cádmio/toxicidade , Intoxicação por Metais Pesados , Intoxicação/etiologia , Verduras/química , Animais , Cádmio/análise , Cádmio/metabolismo , Contaminação de Alimentos/análise , Humanos , Metais Pesados/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Intoxicação/metabolismo , Medição de Risco , Verduras/metabolismoRESUMO
Chlorine (Cl2) gas exposure and toxicity remains a concern in military and industrial sectors. While post-Cl2 exposure damage to the lungs and other tissues has been documented and major underlying mechanisms elucidated, no targeted therapeutics that are effective when administered post-exposure, and which are amenable to mass-casualty scenarios have been developed. Our recent studies show nitrite administered by intramuscular (IM) injection post-Cl2 exposure is effective in preventing acute lung injury and improving survival in rodent models. Our goal in this study was to develop a rabbit model of Cl2 toxicity and test whether nitrite affords protection in a non-rodent model. Exposure of New Zealand White rabbits to Cl2 gas (600ppm, 45min) caused significant increases in protein and neutrophil accumulation in the airways and â¼35% mortality over 18h. Nitrite administered 30min post Cl2 exposure by a single IM injection, at 1mg/kg or 10mg/kg, prevented indices of acute lung injury at 6h by up to 50%. Moreover, all rabbits that received nitrite survived over the study period. These data provide further rationale for developing nitrite as post-exposure therapeutic to mitigate against Cl2 gas exposure injury.