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1.
Artigo em Inglês | MEDLINE | ID: mdl-33573452

RESUMO

The aim of this paper is to study the clinical features of severe intoxications with thallium salts and developing effective care schemes for the application of potassium hexacyanoferrate (II) and deferasirox for correction of detected disorders. A total of 39 patients diagnosed with severe thallium salt poisoning were examined in two groups. Group I comprised 20 patients with severe thallium salt poisoning, who were prescribed with potassium-iron hexacyanoferrate in a dose of 250 mg/kg/day per os, intravenous potassium infusions, furosemide intravenously in amount of 40 mg three times per, and hemodialysis until the thallium level in the blood dropped below 10 mg/L, lactulose 30 mL two times per day per os. Group II consisted of 19 people with severe thallium salt poisoning, which in addition to the above treatment, received Deferasirox in a dosage of 500 mg two times per day per os. The clinical picture of severe poisoning with thallium salts is characterized by lesions of the gastrointestinal tract, nervous system (central and peripheral), alopecia, heart rhythm disorders, and myocardial ischemia zones. Extension of standard therapy with potassium-iron by adding hexacyanoferrate deferasirox showed better effect on thallium elimination rate and improved functional state of liver and kidneys in patients with severe thallium salt poisoning.


Assuntos
Intoxicação por Metais Pesados/terapia , Sais/intoxicação , Tálio/intoxicação , Deferasirox/administração & dosagem , Quimioterapia Combinada , Ferrocianetos/administração & dosagem , Intoxicação por Metais Pesados/fisiopatologia , Humanos , Infusões Intravenosas , Potássio/administração & dosagem , Diálise Renal , Sais/sangue , Sais/isolamento & purificação , Tálio/sangue , Tálio/isolamento & purificação
2.
Learn Mem ; 27(9): 395-413, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32817306

RESUMO

A set of common-acting iron-responsive 5'untranslated region (5'UTR) motifs can fold into RNA stem loops that appear significant to the biology of cognitive declines of Parkinson's disease dementia (PDD), Lewy body dementia (LDD), and Alzheimer's disease (AD). Neurodegenerative diseases exhibit perturbations of iron homeostasis in defined brain subregions over characteristic time intervals of progression. While misfolding of Aß from the amyloid-precursor-protein (APP), alpha-synuclein, prion protein (PrP) each cause neuropathic protein inclusions in the brain subregions, iron-responsive-like element (IRE-like) RNA stem-loops reside in their transcripts. APP and αsyn have a role in iron transport while gene duplications elevate the expression of their products to cause rare familial cases of AD and PDD. Of note, IRE-like sequences are responsive to excesses of brain iron in a potential feedback loop to accelerate neuronal ferroptosis and cognitive declines as well as amyloidosis. This pathogenic feedback is consistent with the translational control of the iron storage protein ferritin. We discuss how the IRE-like RNA motifs in the 5'UTRs of APP, alpha-synuclein and PrP mRNAs represent uniquely folded drug targets for therapies to prevent perturbed iron homeostasis that accelerates AD, PD, PD dementia (PDD) and Lewy body dementia, thus preventing cognitive deficits. Inhibition of alpha-synuclein translation is an option to block manganese toxicity associated with early childhood cognitive problems and manganism while Pb toxicity is epigenetically associated with attention deficit and later-stage AD. Pathologies of heavy metal toxicity centered on an embargo of iron export may be treated with activators of APP and ferritin and inhibitors of alpha-synuclein translation.


Assuntos
Regiões 5' não Traduzidas/efeitos dos fármacos , Peptídeos beta-Amiloides/metabolismo , Ferritinas/metabolismo , Ferroptose/fisiologia , Intoxicação por Metais Pesados/metabolismo , Proteínas Reguladoras de Ferro/metabolismo , Transtornos Neurocognitivos/metabolismo , Doenças Neurodegenerativas/metabolismo , Fármacos Neuroprotetores/farmacologia , Biossíntese de Proteínas/efeitos dos fármacos , alfa-Sinucleína/metabolismo , Peptídeos beta-Amiloides/efeitos dos fármacos , Animais , Ferritinas/efeitos dos fármacos , Ferroptose/efeitos dos fármacos , Intoxicação por Metais Pesados/tratamento farmacológico , Intoxicação por Metais Pesados/fisiopatologia , Humanos , Proteínas Reguladoras de Ferro/efeitos dos fármacos , Transtornos Neurocognitivos/tratamento farmacológico , Doenças Neurodegenerativas/tratamento farmacológico , alfa-Sinucleína/efeitos dos fármacos
3.
Clin Toxicol (Phila) ; 57(11): 1095-1102, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30856020

RESUMO

Background: Aluminium phosphide (AlP) poisoning is associated with a high mortality rate when patients are complicated with myocardial dysfunction and refractory shock or severe metabolic acidosis. We studied the role of veno-arterial extra-corporeal membrane oxygenation (VA-ECMO) in patients of AlP poisoning induced myocardial dysfunction. Methods and results: This is a tertiary care, single-centre, retrospective study. Between January 2011 and June 2016, total of 107 patients with AlP poisoning were identified and of those 67 were categorised in high-risk category as per the criteria. The in-hospital mortality of patients who received ECMO (n = 35) was compared to those who received conventional treatment (n = 32) only. The use of ECMO in addition to conventional treatment has reduced the in-hospital mortality from 84.4% to 40% (odds ratio: 0.47; 95% confidence interval 0.31-0.73). Among survivors, the ECMO group had a significantly lower baseline left ventricular ejection fraction (LVEF; median: 24%; IQR: 22-29 vs. median: 32%; IQR: 32-33.5; p < .003) but a non-significantly higher LVEF at the time of discharge (median: 52%; IQR: 48-60 vs. median: 48%; IQR: 47-49; p: .064) than did the conventional group. On logistic regression analysis the higher sequential organ failure assessment (SOFA) score, lower pH and the non-usage of ECMO were found to be the independent predictors of mortality. Conclusion: The use of ECMO in high-risk patient of AlP poisoning has resulted in a significant reduction in the mortality. A high baseline SOFA score has been found to be the independent predictor of mortality.


Assuntos
Compostos de Alumínio/intoxicação , Cardiomiopatias/induzido quimicamente , Oxigenação por Membrana Extracorpórea/métodos , Intoxicação por Metais Pesados/fisiopatologia , Intoxicação por Metais Pesados/terapia , Fosfinas/intoxicação , Adulto , Feminino , Intoxicação por Metais Pesados/mortalidade , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Função Ventricular Esquerda
4.
Sci Rep ; 9(1): 4253, 2019 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-30862878

RESUMO

Heavy metal toxicity is an ecological concern in regions affected by processes like mining, industry, and agriculture. At sufficiently high concentrations, heavy metals are lethal to honey bees, but little is known about how sublethal doses affect honey bees or whether they will consume contaminated food. We investigated whether honey bees reject sucrose solutions contaminated with three heavy metals - cadmium, copper, and lead - as a measure of their ability to detect the metals, and whether ingesting these metals altered the bees' sucrose sensitivity. The metals elicited three different response profiles in honey bees. Cadmium was not rejected in any of the assays, and ingesting cadmium did not alter sucrose sensitivity. Copper was rejected following antennal stimulation, but was readily consumed following proboscis stimulation. Ingestion of copper did not alter sucrose sensitivity. Lead appeared to be palatable at some concentrations and altered the bees' sensitivity to and/or valuation of sucrose following antennal stimulation or ingestion of the metal. These differences likely represent unique mechanisms for detecting each metal and the pathology of toxicity. The bees' ability to detect and consume these toxic metals highlights the risk of exposure to these elements for bees living in or near contaminated environments.


Assuntos
Abelhas/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Comportamento Alimentar/efeitos dos fármacos , Intoxicação por Metais Pesados/veterinária , Metais Pesados/toxicidade , Animais , Antenas de Artrópodes/efeitos dos fármacos , Antenas de Artrópodes/fisiologia , Abelhas/fisiologia , Relação Dose-Resposta a Droga , Comportamento Alimentar/fisiologia , Intoxicação por Metais Pesados/fisiopatologia , Solo/química , Paladar/fisiologia , Estados Unidos , Água/química
5.
Arh Hig Rada Toksikol ; 70(4): 256-264, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32623859

RESUMO

Metallothioneins are peculiar cysteine rich, heat resistant, small cellular plasma proteins expressed through almost all life forms. The currently established biological functions of metallothioneins are the homeostasis of essential metals and protection against toxic transitional metals (TM) alongside defence from oxidative stress by direct scavenging of reactive oxygen and nitrogen species (ROS and RNS). In mammals, among the four main evolutionary conserved forms, only the ubiquitously expressed metallothionein 1 and 2 (here abbreviated as MT) are inducible by TM, oxidative stress, glucocorticoids and starvation among various other stimuli. However, more than sixty years after being discovered, metallothioneins still bear unresolved issues about their possible physiological function and regulation. The biological function of MTs has still not been associated with the in vitro-demonstrated capacity of MT interaction with cellular molecules glutathione (GSH) or adenosine triphosphate (ATP), or with the possibility of direct iron-MT binding in the reducing intracellular environment of some organelles, e.g. lysosomes. Iron as the most abundant cellular TM is also one of the main physiological sources of ROS. Moreover, iron exhibits strain, sex and age differences that reflected ROS generation and MT induction in (patho)physiology and toxicology studies. A recent study showed that iron sex differences follows expression of both ferritin and MT leading to wide implications from essential TM interconnectivity to aging. This review places emphasis on biochemically proven but physiologically ignored interactions of MT with iron to stimulate advanced research for establishing a wide frame of the biological roles of MTs important for health and longevity.


Assuntos
Peixes , Substâncias Perigosas/química , Intoxicação por Metais Pesados/fisiopatologia , Mamíferos , Metalotioneína/química , Metalotioneína/toxicidade , Estresse Oxidativo , Animais , Humanos , Estrutura Molecular
6.
Brain Res Bull ; 145: 81-86, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29944947

RESUMO

The impact of concurrent exposure to neurotoxic metals is a significant threat to brain function, mostly in contexts of multiple exposures as seen in the developing world. Ninety-five children (46 boys and 49 girls, 6 to 11-year old) from Congo-Kinshasa were assessed for cognition using the Kaufman Assessment Battery for Children (2nd edition) and exposure to Cr, Cu, Zn, Co, Mn, As, Cd, Se, Hg, Fe, and Pb by inductively coupled plasma mass spectrometry (ICPMS) in serum and urine collections. Concentrations of elements were all above normal ranges except for Cd, Se and Hg. General linear mixed effects models were used to predict neurocognitive outcomes with variable selection methods including backward elimination, elastic net, or subsets identified based on subject matter expertise. After adjusting for sex, age, and SES, urinary Co > 5 µg/l was associated with poor simultaneous processing (memory) (p = 0.0237). Higher excretion but normal concentration of Cd in serum was associated with better memory (p = 0.03), planning (p = 0.05), and overall performance scores (p < 0.01); thus appeared to be neuroprotective. However, higher excretion of Zn had negative influence on the overall performance scores (p = 0.02). Predictive neurotoxicology is a challenging task in contexts of multiple and concurrent exposures. Urinary Co > 5 µg/l is a risk factor for poor neurodevelopmental outcomes in such contexts. The impact of heavy metals on cognition is dependent on concentrations of and interactions between toxic and essential elements.


Assuntos
Intoxicação por Metais Pesados/epidemiologia , Metais Pesados/efeitos adversos , Metais Pesados/toxicidade , Criança , Pré-Escolar , Cognição/efeitos dos fármacos , Cognição/fisiologia , Estudos Transversais , República Democrática do Congo/epidemiologia , Feminino , Intoxicação por Metais Pesados/fisiopatologia , Humanos , Masculino
7.
Int J Mol Sci ; 18(5)2017 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-28498320

RESUMO

Chronic kidney disease (CKD) is a common progressive disease that is typically characterized by the permanent loss of functional nephrons. As injured nephrons become sclerotic and die, the remaining healthy nephrons undergo numerous structural, molecular, and functional changes in an attempt to compensate for the loss of diseased nephrons. These compensatory changes enable the kidney to maintain fluid and solute homeostasis until approximately 75% of nephrons are lost. As CKD continues to progress, glomerular filtration rate decreases, and remaining nephrons are unable to effectively eliminate metabolic wastes and environmental toxicants from the body. This inability may enhance mortality and/or morbidity of an individual. Environmental toxicants of particular concern are arsenic, cadmium, lead, and mercury. Since these metals are present throughout the environment and exposure to one or more of these metals is unavoidable, it is important that the way in which these metals are handled by target organs in normal and disease states is understood completely.


Assuntos
Intoxicação por Metais Pesados/metabolismo , Metais Pesados/toxicidade , Insuficiência Renal Crônica/metabolismo , Animais , Exposição Ambiental/efeitos adversos , Intoxicação por Metais Pesados/complicações , Intoxicação por Metais Pesados/fisiopatologia , Humanos , Metais Pesados/farmacocinética , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/fisiopatologia
8.
Biol Trace Elem Res ; 180(2): 265-274, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28417309

RESUMO

Cadmium (Cd) is a toxic environmental and occupational pollutant with reported toxic effects on the kidneys, liver, lungs, bones, and the immunity system. Based on its physicochemical similarity to cadmium, zinc (Zn) shows protective effects against cadmium toxicity and cadmium accumulation in the body. Nano-zinc and nano-zinc oxide (ZnO), recently used in foods and pharmaceutical products, can release a great amount of Zn2+ in their environment. This research was carried out to investigate the more potent properties of the metal zinc among sub-acute cadmium intoxicated rats. Seventy-five male Wistar rats were caged in 15 groups. Cadmium chloride (CdCl2) was used in drinking water to induce cadmium toxicity. Different sizes (15, 20, and 30 nm) and doses of nano-zinc particles (3, 10, 100 mg/kg body weight [bw]) were administered solely and simultaneously with CdCl2 (2-5 mg/kg bw) for 28 days. The experimental animals were decapitated, and the biochemical biomarkers (enzymatic and non-enzymatic) were determined in their serum after oral exposure to nano-zinc and cadmium. Statistical analysis was carried out with a one-way ANOVA and t test. P < 0.05 was considered as statistically significant. The haematocrit (HCT) significantly increased and blood coagulation time significantly reduced in the nano-zinc-treated rats. AST, ALT, triglyceride, total cholesterol, LDL, and free fatty acids increased significantly in the cadmium- and nano-zinc-treated rats compared with the controls. However, albumin, total protein, and HDLc significantly decreased in the cadmium- and nano-zinc-treated rats compared with the controls (P < 0.05). It seems that in the oral administration of nano-zinc, the smaller sizes with low doses and the larger sizes with high doses are more toxic than metallic zinc. In a few cases, an inverse dose-dependent relationship was seen as well. This research showed that in spite of larger sizes of zinc, smaller sizes of nano-zinc particles are not suitable for protection against cadmium intoxication.


Assuntos
Cádmio/toxicidade , Suplementos Nutricionais/efeitos adversos , Poluentes Ambientais/toxicidade , Intoxicação por Metais Pesados/etiologia , Nanopartículas Metálicas/administração & dosagem , Oxidantes/efeitos adversos , Zinco/efeitos adversos , Animais , Biomarcadores/sangue , Cádmio/química , Cloreto de Cádmio/administração & dosagem , Cloretos/efeitos adversos , Cloretos/uso terapêutico , Suplementos Nutricionais/análise , Poluentes Ambientais/antagonistas & inibidores , Intoxicação por Metais Pesados/sangue , Intoxicação por Metais Pesados/fisiopatologia , Hematócrito , Masculino , Nanopartículas Metálicas/efeitos adversos , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Transmissão , Oxidantes/administração & dosagem , Oxidantes/química , Oxidantes/uso terapêutico , Tamanho da Partícula , Substâncias Protetoras/administração & dosagem , Substâncias Protetoras/efeitos adversos , Substâncias Protetoras/química , Substâncias Protetoras/uso terapêutico , Distribuição Aleatória , Ratos Wistar , Insuficiência Renal/etiologia , Insuficiência Renal/prevenção & controle , Testes de Toxicidade Subaguda , Tempo de Coagulação do Sangue Total , Zinco/administração & dosagem , Zinco/química , Zinco/uso terapêutico , Compostos de Zinco/efeitos adversos , Compostos de Zinco/uso terapêutico , Óxido de Zinco/administração & dosagem
9.
Biol Trace Elem Res ; 180(2): 191-205, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28424967

RESUMO

Imbalances in the concentrations of trace metals have become an increasingly recognized source of infirmity worldwide particularly in the development of ischemia heart disease (IHD). Present study is intended to analyze the concentrations of Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Pb, Sr, and Zn in the blood and scalp hair of the patients and counterpart controls by flame atomic absorption spectrometry after wet-acid digestion. On the average, Cd, Co, Cr, Fe, K, Li, Mn, Na, and Pb revealed significantly elevated concentrations in the blood of the patients compared with the controls (p < 0.05), whereas mean levels of Ca, Cd, Fe, K, Li, Pb, and Sr in the scalp hair were significantly higher in the patients than the controls (p < 0.05). Most of the metals exhibited noticeable disparities in their concentrations based on gender, abode, dietary/smoking habits, and occupations of both donor groups. The correlation study and multivariate statistical analyses revealed some significantly divergent associations and apportionment of the metals in both donor groups. Overall, comparative variations of the metal contents in blood/scalp hair of the patients were significantly different than the controls; thus, evaluation of trace metals status may be indicative of pathological disorders, such as IHD.


Assuntos
Doença da Artéria Coronariana/metabolismo , Poluentes Ambientais/metabolismo , Disparidades nos Níveis de Saúde , Intoxicação por Metais Pesados/diagnóstico , Metais Pesados/metabolismo , Isquemia Miocárdica/metabolismo , Desequilíbrio Hidroeletrolítico/diagnóstico , Adulto , Análise por Conglomerados , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/etiologia , Dieta/efeitos adversos , Monitoramento Ambiental , Poluentes Ambientais/sangue , Poluentes Ambientais/toxicidade , Feminino , Cabelo/metabolismo , Intoxicação por Metais Pesados/epidemiologia , Intoxicação por Metais Pesados/fisiopatologia , Humanos , Masculino , Metais Pesados/sangue , Metais Pesados/toxicidade , Isquemia Miocárdica/sangue , Isquemia Miocárdica/epidemiologia , Isquemia Miocárdica/etiologia , Paquistão/epidemiologia , Análise de Componente Principal , Fatores de Risco , Couro Cabeludo , Fatores Sexuais , Fumar/efeitos adversos , Fatores Socioeconômicos , Desequilíbrio Hidroeletrolítico/epidemiologia , Desequilíbrio Hidroeletrolítico/fisiopatologia
10.
Biol Trace Elem Res ; 180(2): 285-296, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28353138

RESUMO

This study aimed to investigate the effects of selenium on the ion profiles in the heart, liver, spleen, and kidney through the oral administration of hexavalent chromium. Approximately 22.14 mg/kg b.w. K2Cr2O7 was added to water to establish a chronic poisoning model. Different selenium levels (0.00, 0.31, 0.63, 1.25, 2.50, and 5.00 mg Na2SeO3/kg b.w.) around the safe dose were administered to the experimental group model. Ca, Mg, Mn, Fe, Cu, and Zn were detected in the organs through flame atomic absorption spectrometry after these organs were exposed to K2Cr2O7 and Na2SeO3 for 14, 28, and 42 days. Results showed that these elements exhibited various changes. Ca contents declined in the heart, liver, and spleen. Ca contents also decreased on the 28th day and increased on the 42nd day in the kidney. Mn contents declined in the heart and spleen but increased in the kidney. Mn contents also decreased on the 28th day and increased on the 42nd day in the liver. Cu contents declined in the heart and spleen. Cu contents increased on the 28th day and decreased on the 42nd day in the liver and kidney. Zn contents declined in the heart and spleen. Zn contents increased on the 28th day and decreased on the 42nd day in the liver and kidney. Fe contents decreased in the heart and liver. Fe contents increased on the 28th day and decreased on the 42nd day in the spleen and kidney. Mg contents did not significantly change in these organs. Appropriate selenium contents enhanced Mn and Zn contents, which were declined by chromium. Conversely, appropriate selenium contents reduced Ca, Fe, and Cu contents, which were increased by chromium. In conclusion, the exposure of chickens to K2Cr2O7 induced changes in different trace elements, and Na2SeO3 supplementation could alleviate this condition.


Assuntos
Cromo/intoxicação , Intoxicação por Metais Pesados/veterinária , Doenças das Aves Domésticas/prevenção & controle , Substâncias Protetoras/uso terapêutico , Selenito de Sódio/uso terapêutico , Oligoelementos/metabolismo , Desequilíbrio Hidroeletrolítico/veterinária , Administração Oral , Animais , Animais Endogâmicos , Galinhas , China , Cromo/administração & dosagem , Cromo/química , Relação Dose-Resposta a Droga , Coração/efeitos dos fármacos , Intoxicação por Metais Pesados/etiologia , Intoxicação por Metais Pesados/fisiopatologia , Intoxicação por Metais Pesados/prevenção & controle , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Miocárdio/metabolismo , Dicromato de Potássio/administração & dosagem , Doenças das Aves Domésticas/etiologia , Doenças das Aves Domésticas/metabolismo , Doenças das Aves Domésticas/fisiopatologia , Substâncias Protetoras/administração & dosagem , Distribuição Aleatória , Selenito de Sódio/administração & dosagem , Baço/efeitos dos fármacos , Baço/metabolismo , Oligoelementos/deficiência , Desequilíbrio Hidroeletrolítico/etiologia , Desequilíbrio Hidroeletrolítico/prevenção & controle
11.
Biol Trace Elem Res ; 180(2): 239-245, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28357648

RESUMO

The aim of the study was to assess the protective effect of (-)-epigallocatechin gallate (EGCG), a flavonoid abundant in green tea, against ammonium metavanadate (AMV)-induced oxidative stress in male Wistar rats. Four groups of animals have been used, a control group and three test groups. In the first test group, AMV was intra-peritoneally (i.p) injected daily (5 mg/kg body weight for five consecutive days). The second test group of animals was also injected daily with EGCG (5 mg/kg body weight) during the same period. However, the third test group was i.p. injected with both AMV and EGCG (5 mg/kg body weight for five consecutive days). When given alone, AMV induced an oxidative stress evidenced by an increase of lipid peroxidation levels (expressed as TBARS concentration) in kidney. In these animals, activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) were significantly decreased, suggesting significant reduction of the antioxidant defense system at the cell level. Kidney histological sections, showed glomerular hypertrophy and tubular dilatation. In AMV-treated animals receiving EGCG, the oxidative stress was much less pronounced and activities of antioxidant enzymes were kept close to control values. Histopathological changes were less prominent. Our results confirm that green tea and other sources of flavonoids might confer a strong protection against ammonium metavanadate-induced oxidative stress.


Assuntos
Injúria Renal Aguda/prevenção & controle , Catequina/análogos & derivados , Intoxicação por Metais Pesados/fisiopatologia , Rim/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/uso terapêutico , Vanádio/intoxicação , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Animais , Antioxidantes/administração & dosagem , Antioxidantes/efeitos adversos , Antioxidantes/uso terapêutico , Catequina/administração & dosagem , Catequina/efeitos adversos , Catequina/uso terapêutico , Intoxicação por Metais Pesados/etiologia , Hipertrofia , Injeções Intraperitoneais , Rim/metabolismo , Rim/patologia , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/metabolismo , Glomérulos Renais/patologia , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Oxirredutases/antagonistas & inibidores , Oxirredutases/metabolismo , Substâncias Protetoras/administração & dosagem , Substâncias Protetoras/efeitos adversos , Ratos Wistar , Vanadatos/administração & dosagem , Vanádio/administração & dosagem , Vitamina A/agonistas , Vitamina A/antagonistas & inibidores , Vitamina A/sangue , Vitamina E/agonistas , Vitamina E/antagonistas & inibidores , Vitamina E/sangue
12.
Int J Toxicol ; 33(4): 288-296, 2014 07.
Artigo em Inglês | MEDLINE | ID: mdl-24808049

RESUMO

Using rats fed 22 g/d of a control diet containing 0.005% zinc (Zn) or 2 Zn-excess diets containing 0.05% or 0.2% Zn for 4 weeks, we examined the mechanisms involved in the deterioration of renal function induced by Zn-excess intake. An increase in Zn intake elevated mean blood pressure (BP) and reduced renal blood flow (RBF) and inulin clearance in a dose-dependent manner. This decline in inulin clearance may be derived from a fall in RBF. Administration of the nitric oxide (NO) synthase inhibitor, Nω-nitro-l-arginine methyl ester, markedly increased mean BP and significantly decreased RBF in the 3 groups of rats. Administration of the exogenous superoxide radical (OO-) scavenger, tempol, significantly decreased mean BP and substantially increased RBF in all groups of rats. These observations suggest that both an elevation in systemic BP and a reduction in RBF seen in the 2 Zn-excess diet groups result from a decrease in the action of the vasodilator, NO, through the formation of peroxynitrite based on the nonenzymatic reaction of NO and increased OO- Indeed, the activity of the endogenous OO- scavenger, copper/Zn-superoxide dismutase, was significantly reduced in the vessel wall of rats fed 2 Zn-excess diets versus a control diet. 8-Hydroxy-2'-deoxyguanosine formation caused by OO- generation was notably elevated in the kidneys of rats fed 2 Zn-excess diets relatively to rats fed a control diet. Thus, Zn-excess intake leads to the aggravation of renal function concomitantly with an increase in systemic BP predominantly through the oxidative stress caused by OO.


Assuntos
Suplementos Nutricionais/intoxicação , Intoxicação por Metais Pesados/fisiopatologia , Hipertensão Renovascular/etiologia , Rim/fisiopatologia , Estresse Oxidativo , Insuficiência Renal/etiologia , Zinco/intoxicação , 8-Hidroxi-2'-Desoxiguanosina , Animais , Aorta Torácica , Biomarcadores/sangue , Biomarcadores/metabolismo , Biomarcadores/urina , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Inibidores Enzimáticos/efeitos adversos , Sequestradores de Radicais Livres/uso terapêutico , Intoxicação por Metais Pesados/tratamento farmacológico , Intoxicação por Metais Pesados/metabolismo , Intoxicação por Metais Pesados/patologia , Hipertensão Renovascular/fisiopatologia , Hipertensão Renovascular/prevenção & controle , Inulina/sangue , Inulina/farmacocinética , Inulina/urina , Rim/irrigação sanguínea , Rim/efeitos dos fármacos , Rim/patologia , Masculino , Taxa de Depuração Metabólica/efeitos dos fármacos , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Distribuição Aleatória , Ratos Sprague-Dawley , Insuficiência Renal/fisiopatologia , Insuficiência Renal/prevenção & controle , Superóxido Dismutase-1/antagonistas & inibidores , Superóxido Dismutase-1/metabolismo
13.
Rev. argent. dermatol ; 88(1): 28-37, ene.-mar. 2007. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-634326

RESUMO

Se estudiaron los efectos teratogénicos de metales pesados (acetatos de Cd2+ y Pb2+ y sulfato de Cu2+), en embriones de pollo en desarrollo, después de la administración de una monodosis del metal. Los huevos embrionados fueron inyectados en la yema en el día 12 de incubación. Las concentraciones de los iones fueron (nmoles/g huevo): Cd2+: Dosis 1 (D1): 0,16 y Dosis 2 (D2): 0,32; Pb2+: D1: 8,0 y D2: 16,0 y Cu2+: D1: 1,7 y D2: 3,3. Los resultados se evaluaron después de continuar la incubación in ovo durante 12 y 60 hs Cu2+ y Pb2+ no aumentaron la mortalidad de los embriones, en cambio, la presencia de Cd2+ produjo entre 30 y 86 % de mortalidad de los embriones, con efectos dosis y tiempo dependientes. Los embriones intoxicados con la D2 de Cd2+ durante 60 hs fueron los únicos ejemplares que presentaron disminución en su peso promedio, respecto de los ejemplares de control. La administración de Cd2+ causó efectos teratogénicos más severos que los tratamientos con Cu2+ y Pb2+. Se puede concluir que los metales pesados son embriotóxicos e inducen teratogenia en embriones de pollo en desarrollo. Se sugiere que los mejores parámetros para evaluar la teratogenicidad producida por la intoxicación Cd2+, Cu2+ y Pb2+ son los derrames cutáneos y hepáticos.


Teratogenic effects of heavy metals (Cd2+- and Pb2+- acetates and Cu2+- suphate) were studied on chick embryos, after the administration as a single dose. Test materials were injected into the yolk on day 12 of incubation. Tested concentrations were (nmole/g egg): Cd2+ Dose 1 (D1): 0.16 and Dose 2 (D2): 0.32; Pb2+: D1: 8.0 and D2: 16.0 and Cu2+: D1: 1.7 and D2: 3.3. Evaluations were performed after in ovo incubation for 12 and 60 hours. Embryonic mortality did not increase at the two dose levels of Cu2+ and Pb2+, while Cd2+ caused 30 and 86% of mortality, showing dose and time responses. Eggs treated with D2 of Cd2+ for 60 hs, significantly decreased the average of body mass embryo, when compared to the control group. Cd2+ administration was responsible for the most severe teratogenic signs compared to Cu2+ and Pb2+ treatments. It can be concluded that heavy metals are embryotoxic and teratogenics. We suggest that cutaneous and liver hemorrhages are the best signs to evaluate teratogenicity induced by Cd2+, Cu2+ and Pb2+.


Assuntos
Animais , Embrião de Galinha , Intoxicação por Metais Pesados/embriologia , Intoxicação por Metais Pesados/fisiopatologia , Manifestações Cutâneas , Teratogênicos/toxicidade , Toxicidade/efeitos adversos
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