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1.
BMC Complement Altern Med ; 16: 234, 2016 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-27450510

RESUMO

BACKGROUND: Plant medicinal extracts may be claimed to prevent or cure chemical intoxications. Few of these are tested for their mechanisms of actions in vivo and for their cellular impacts. In 2011, we demonstrated that hepatic cell mortality induced by environmentally realistic levels of the widely used herbicide Roundup (R) in vitro can be almost entirely prevented by plant extracts called Dig1 (D, Digeodren). METHODS: We tested the in vivo effects of D alone (1.2 ml/kg bw/d), but also prior to and during 8 days of R intoxication (at 135 mg/kg bw/d) in a total of 4 groups of 40 adult Sprague-Dawley male rats each. After treatments, horizontal and vertical locomotor activities of the animals were measured by use of actimeters. Brain, liver, kidneys, heart and testes were collected and weighted. Body weights as well as feed and water consumption were recorded. Proteins, creatinine, urea, phosphate, potassium, sodium, calcium, chloride ions, testosterone, estradiol, AST and ALT were measured in serum. In liver S9 fractions, GST, GGT, and CYP450 (1A2, 2C9, 2C19, 2D6, 3A4) were assessed. RESULTS: D did not have any physiological or biochemical observable impact alone at 2 %. Out of a total of 29 measured parameters, 8 were significantly affected by R absorption within only 8 days. On these 8 parameters, only 2 were not restored by D (GGT activity and plasmatic phosphate), 5 were totally restored (horizontal and vertical locomotor activities, CYP2D6 activity, plasmatic Na + and estradiol), and the 6th was almost restored (plasmatic K+). The specificities of the toxic effects of R and of the therapeutic effects of D treatment were thus demonstrated, both at the behavioural and biochemical levels. CONCLUSIONS: D, without any side effect observable in these conditions, presented strong preventive and therapeutic properties in vivo after a short-term intoxication by the widely used pesticide Roundup.


Assuntos
Encéfalo/efeitos dos fármacos , Glicina/análogos & derivados , Herbicidas/toxicidade , Fígado/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Encéfalo/metabolismo , Glicina/toxicidade , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/metabolismo , Masculino , Tamanho do Órgão/efeitos dos fármacos , Extratos Vegetais/química , Substâncias Protetoras/química , Ratos , Ratos Sprague-Dawley , Glifosato
2.
Exp Biol Med (Maywood) ; 241(5): 527-38, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26748397

RESUMO

Propofol has been shown to exert cardioprotection, but the underlying mechanisms remain incompletely understood. We examined: (1) whether propofol-induced cardioprotection depended on the time and the dose of administration; (2) the role of mitochondrial adenosine triphosphate-sensitive potassium channels, nitric oxide synthase, and mitochondrial respiratory chain activity in propofol-induced cardioprotection. Human right atrial trabeculae were obtained during cardiopulmonary bypass for coronary artery bypass and aortic valve replacement. Isometric force of contraction of human right atrial trabeculae hanged in an oxygenated Tyrode's solution was recorded during 30-min hypoxia and 60-min reoxygenation (Control). Propofol 0.1, 1, and 10 µM was administered: (1) 5 min before hypoxia until the end of the experiment; (2) 5 min followed by 5-min washout before hypoxia; (3) during the reoxygenation period, propofol 10 µM was administered in presence of 5-hydroxydecanoate (antagonist of mitochondrial adenosine triphosphate-sensitive potassium channels), and NG-nitro-L-arginine methyl ester (inhibitor of nitric oxide synthase). In addition, mitochondria were isolated from human right atrial at 15 min of reoxygenation. The effect of propofol on activity of the mitochondrial respiratory chain complexes was evaluated by spectrophotometry. The force of contraction (% of baseline) and the complex activity between the different groups were compared with an analysis of variance and post hoc test. Propofol 10 µM administered during the reoxygenation period significantly improved the recovery of force of contraction at the end of reoxygenation (82 ± 6% of baseline value vs. 49 ± 6% in Control; P < 0.001). The beneficial effects of propofol 10 µM were abolished by co-administration with 5-hydroxydecanoate (53 ± 8%) or NG-nitro-L-arginine methyl ester (57 ± 6%). Propofol 10 µM significantly increased enzymatic activities of the mitochondrial respiratory chain complexes, in reoxygenation period, compared to their respective untreated controls. In conclusion, in human myocardium, propofol-induced cardioprotection was mediated by mitochondrial adenosine triphosphate-sensitive potassium channels opening, nitric oxide synthase activation and stimulation of mitochondrial respiratory chain complexes, in early reoxygenation period.


Assuntos
Anestésicos Intravenosos/farmacologia , Cardiotônicos/farmacologia , Transporte de Elétrons/efeitos dos fármacos , Coração/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Propofol/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hipóxia , Canais KATP/metabolismo , Masculino , Pessoa de Meia-Idade , Mitocôndrias/enzimologia , Óxido Nítrico Sintase/metabolismo
3.
Cardiovasc Toxicol ; 15(4): 324-35, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25448876

RESUMO

Roundup (R), a glyphosate (G)-based herbicide (GBH), containing unknown adjuvants is widely dispersed around the world. Used principally by farmers, intoxications have increasingly been reported. We have studied R effects (containing 36 % of G) on right ventricular tissues (male Sprague-Dawley rats, up to 20,000 ppm and female New Zealand rabbits, at 25 and 50 ppm), to investigate R cardiac electrophysiological actions in vitro. We tested the reduced Ca(++) intracellular uptake mechanism as one potential cause of the electrical abnormalities after GBH superfusion, using the Na(+)/K(+)-ATPase inhibitor ouabain or the 1,4-dihydropyridine L-type calcium channel agonist BAY K 8644 which increases I Ca. R concentrations were selected based on human blood ranges found after acute intoxication. The study showed dose-dependent V max, APD50 and APD90 variations during 45 min of R superfusion. At the highest concentrations tested, there was a high incidence of conduction blocks, and 30-min washout with normal Tyrode solution did not restore excitability. We also observed an increased incidence of arrhythmias at different doses of R. Ouabain and BAY K 8644 prevented V max decrease, APD90 increase and the cardiac inexcitability induced by R 50 ppm. Glyphosate alone (18 and 180 ppm) had no significant electrophysiological effects. Thus, the action potential prolonging effect of R pointing to I Ca interference might explain both conduction blocks and proarrhythmia in vitro. These mechanisms may well be causative of QT prolongation, atrioventricular conduction blocks and arrhythmias in man after GBH acute intoxications as reported in retrospective hospital records.


Assuntos
Arritmias Cardíacas/induzido quimicamente , Glicina/análogos & derivados , Sistema de Condução Cardíaco/efeitos dos fármacos , Ventrículos do Coração/efeitos dos fármacos , Herbicidas/toxicidade , Miócitos Cardíacos/efeitos dos fármacos , Potenciais de Ação , Animais , Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/fisiopatologia , Cálcio/metabolismo , Agonistas dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo L/efeitos dos fármacos , Canais de Cálcio Tipo L/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Feminino , Glicina/toxicidade , Sistema de Condução Cardíaco/metabolismo , Sistema de Condução Cardíaco/fisiopatologia , Ventrículos do Coração/metabolismo , Ventrículos do Coração/fisiopatologia , Técnicas In Vitro , Masculino , Miócitos Cardíacos/metabolismo , Coelhos , Ratos Sprague-Dawley , Medição de Risco , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , ATPase Trocadora de Sódio-Potássio/metabolismo , Fatores de Tempo , Glifosato
4.
Cardiovasc Toxicol ; 15(2): 117-26, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25245870

RESUMO

In glyphosate (G)-based herbicides (GBHs), the declared active principle G is mixed with several adjuvants that help it to penetrate the plants' cell membranes and its stabilization and liposolubility. Its utilization is growing with genetically modified organisms engineered to tolerate GBH. Millions of farmers suffer poisoning and death in developing countries, and occupational exposures and suicide make GBH toxicity a worldwide concern. As GBH is found in human plasma, widespread hospital facilities for measuring it should be encouraged. Plasma determination is an essential prerequisite for risk assessment in GBH intoxication. Only when standard ECGs were performed, at least one abnormal ECG was detected in the large majority of cases after intoxication. QTc prolongation and arrhythmias along with first-degree atrioventricular block were observed after GBH intoxication. Thus, life-threatening arrhythmias might be the cause of death in GBH intoxication. Cardiac cellular effects of GBH were reviewed along with few case reports in men and scanty larger studies. We observed in two mammalian species (rats and rabbits) direct cardiac electrophysiological changes, conduction blocks and arrhythmias among GBH-mediated effects. Plasmatic (and urine) level determinations of G and electrocardiographic Holter monitoring seem warranted to ascertain whether cardiovascular risk among agro-alimentary workers might be defined.


Assuntos
Doenças Cardiovasculares/induzido quimicamente , Sistema Cardiovascular/efeitos dos fármacos , Glicina/análogos & derivados , Herbicidas/toxicidade , Animais , Doenças Cardiovasculares/diagnóstico , Sistema Cardiovascular/patologia , Glicina/efeitos adversos , Glicina/toxicidade , Herbicidas/efeitos adversos , Humanos , Glifosato
5.
Environ Toxicol Pharmacol ; 38(1): 131-40, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24930125

RESUMO

Roundup is the major pesticide used in agriculture worldwide; it is a glyphosate-based herbicide. Its molecular effects are studied following an acute exposure (0.5%) of fifteen 60-day-old male rats during an 8-day period. Endocrine (aromatase, estrogen and androgen receptors, Gper1 in testicular and sperm mRNAs) and testicular functions (organ weights, sperm parameters and expression of the blood-testis barrier markers) were monitored at days 68, 87, and 122 after treatment, spermiogenesis and spermatogenesis. The major disruption is an increase of aromatase mRNA levels at least by 50% in treated rats at all times, as well as the aromatase protein. We have also shown a similar increase of Gper1 expression at day 122 and a light modification of BTB markers. A rise of abnormal sperm morphology and a decrease of the expression of protamine 1 and histone 1 testicular in epididymal sperm are observed despite a normal sperm concentration and motility.


Assuntos
Aromatase/genética , Glicina/análogos & derivados , Herbicidas/toxicidade , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Animais , Núcleo Celular/efeitos dos fármacos , Epididimo/anatomia & histologia , Epididimo/efeitos dos fármacos , Epididimo/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glicina/toxicidade , Histonas/genética , Masculino , Tamanho do Órgão/efeitos dos fármacos , Protaminas/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/genética , Espermatozoides/metabolismo , Testículo/anatomia & histologia , Testículo/metabolismo , Glifosato
6.
Environ Sci Eur ; 26(1): 14, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-27752412

RESUMO

BACKGROUND: The health effects of a Roundup-tolerant NK603 genetically modified (GM) maize (from 11% in the diet), cultivated with or without Roundup application and Roundup alone (from 0.1 ppb of the full pesticide containing glyphosate and adjuvants) in drinking water, were evaluated for 2 years in rats. This study constitutes a follow-up investigation of a 90-day feeding study conducted by Monsanto in order to obtain commercial release of this GMO, employing the same rat strain and analyzing biochemical parameters on the same number of animals per group as our investigation. Our research represents the first chronic study on these substances, in which all observations including tumors are reported chronologically. Thus, it was not designed as a carcinogenicity study. We report the major findings with 34 organs observed and 56 parameters analyzed at 11 time points for most organs. RESULTS: Biochemical analyses confirmed very significant chronic kidney deficiencies, for all treatments and both sexes; 76% of the altered parameters were kidney-related. In treated males, liver congestions and necrosis were 2.5 to 5.5 times higher. Marked and severe nephropathies were also generally 1.3 to 2.3 times greater. In females, all treatment groups showed a two- to threefold increase in mortality, and deaths were earlier. This difference was also evident in three male groups fed with GM maize. All results were hormone- and sex-dependent, and the pathological profiles were comparable. Females developed large mammary tumors more frequently and before controls; the pituitary was the second most disabled organ; the sex hormonal balance was modified by consumption of GM maize and Roundup treatments. Males presented up to four times more large palpable tumors starting 600 days earlier than in the control group, in which only one tumor was noted. These results may be explained by not only the non-linear endocrine-disrupting effects of Roundup but also by the overexpression of the EPSPS transgene or other mutational effects in the GM maize and their metabolic consequences. CONCLUSION: Our findings imply that long-term (2 year) feeding trials need to be conducted to thoroughly evaluate the safety of GM foods and pesticides in their full commercial formulations.

7.
Food Chem Toxicol ; 53: 476-83, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23146697

RESUMO

Our recent work (Séralini et al., 2012) remains to date the most detailed study involving the life-long consumption of an agricultural genetically modified organism (GMO). This is true especially for NK603 maize for which only a 90-day test for commercial release was previously conducted using the same rat strain (Hammond et al., 2004). It is also the first long term detailed research on mammals exposed to a highly diluted pesticide in its total formulation with adjuvants. This may explain why 75% of our first criticisms arising within a week, among publishing authors, come from plant biologists, some developing patents on GMOs, even if it was a toxicological paper on mammals, and from Monsanto Company who owns both the NK603 GM maize and Roundup herbicide (R). Our study has limits like any one, and here we carefully answer to all criticisms from agencies, consultants and scientists, that were sent to the Editor or to ourselves. At this level, a full debate is biased if the toxicity tests on mammals of NK603 and R obtained by Monsanto Company remain confidential and thus unavailable in an electronic format for the whole scientific community to conduct independent scrutiny of the raw data. In our article, the conclusions of long-term NK603 and Roundup toxicities came from the statistically highly discriminant findings at the biochemical level in treated groups in comparison to controls, because these findings do correspond in an blinded analysis to the pathologies observed in organs, that were in turn linked to the deaths by anatomopathologists. GM NK603 and R cannot be regarded as safe to date.


Assuntos
Glicina/análogos & derivados , Herbicidas/toxicidade , Plantas Geneticamente Modificadas/toxicidade , Zea mays/toxicidade , Animais , Feminino , Masculino
8.
Food Chem Toxicol ; 50(11): 4221-31, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22999595

RESUMO

The health effects of a Roundup-tolerant genetically modified maize (from 11% in the diet), cultivated with or without Roundup, and Roundup alone (from 0.1 ppb in water), were studied 2 years in rats. In females, all treated groups died 2-3 times more than controls, and more rapidly. This difference was visible in 3 male groups fed GMOs. All results were hormone and sex dependent, and the pathological profiles were comparable. Females developed large mammary tumors almost always more often than and before controls, the pituitary was the second most disabled organ; the sex hormonal balance was modified by GMO and Roundup treatments. In treated males, liver congestions and necrosis were 2.5-5.5 times higher. This pathology was confirmed by optic and transmission electron microscopy. Marked and severe kidney nephropathies were also generally 1.3-2.3 greater. Males presented 4 times more large palpable tumors than controls which occurred up to 600 days earlier. Biochemistry data confirmed very significant kidney chronic deficiencies; for all treatments and both sexes, 76% of the altered parameters were kidney related. These results can be explained by the non linear endocrine-disrupting effects of Roundup, but also by the overexpression of the transgene in the GMO and its metabolic consequences.


Assuntos
Glicina/análogos & derivados , Herbicidas/toxicidade , Plantas Geneticamente Modificadas/toxicidade , Zea mays/toxicidade , Animais , Carcinógenos/toxicidade , Relação Dose-Resposta a Droga , Disruptores Endócrinos/toxicidade , Feminino , Glicina/farmacologia , Glicina/toxicidade , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Neoplasias Mamárias Animais/induzido quimicamente , Microscopia Eletrônica de Transmissão , Necrose/induzido quimicamente , Hipófise/efeitos dos fármacos , Hipófise/patologia , Ratos Sprague-Dawley , Taxa de Sobrevida , Testes de Toxicidade Crônica/métodos , Zea mays/genética , Glifosato
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