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1.
Int J Mol Sci ; 25(12)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38928005

RESUMO

The pregnane X receptor (PXR) is a nuclear hormone receptor that plays a pivotal role in regulating gene expression in response to various ligands, particularly xenobiotics. In this context, the aim of this study was to shed light on the ligand affinity and functions of four NR1J1 paralogs identified in the marine mussel Mytilus galloprovincialis, employing a dual-luciferase reporter assay. To achieve this, the activation patterns of these paralogs in response to various toxins, including freshwater cyanotoxins (Anatoxin-a, Cylindrospermopsin, and Microcystin-LR, -RR, and -YR) and marine algal toxins (Nodularin, Saxitoxin, and Tetrodotoxin), alongside natural compounds (Saint John's Wort, Ursolic Acid, and 8-Methoxypsoralene) and microalgal extracts (Tetraselmis, Isochrysis, LEGE 95046, and LEGE 91351 extracts), were studied. The investigation revealed nuanced differences in paralog response patterns, highlighting the remarkable sensitivity of MgaNR1J1γ and MgaNR1J1δ paralogs to several toxins. In conclusion, this study sheds light on the intricate mechanisms of xenobiotic metabolism and detoxification, particularly focusing on the role of marine mussel NR1J1 in responding to a diverse array of compounds. Furthermore, comparative analysis with human PXR revealed potential species-specific adaptations in detoxification mechanisms, suggesting evolutionary implications. These findings deepen our understanding of PXR-mediated metabolism mechanisms, offering insights into environmental monitoring and evolutionary biology research.


Assuntos
Toxinas Marinhas , Mytilus , Receptor de Pregnano X , Animais , Receptor de Pregnano X/metabolismo , Receptor de Pregnano X/genética , Mytilus/metabolismo , Mytilus/genética , Humanos , Microcistinas/metabolismo , Microalgas/metabolismo , Microalgas/genética , Xenobióticos/metabolismo , Toxinas Bacterianas/metabolismo , Toxinas de Cianobactérias
2.
Environ Res ; 229: 116001, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37116679

RESUMO

Propyl-propane-thiosulfonate (PTSO) is an organosulfur compound found inAllium spp. Due to its antioxidant and antimicrobial activities, PTSO has been proposed for applications in the agri-food sector, such as feed additive. However, its use with commercial purposes depends on its toxicity evaluation. The present work aimed to perform a pilot-study of toxicokinetic profile of PTSO combining in silico and in vitro techniques, important steps in the risk assessment process. In silico ecotoxicity studies were also performed considering the importance of the environmental impact of the compound before its commercial use. First, an analytical method has been developed and validated to determine the original compound and its metabolites by ultra-performance liquid chromatography-tandem mass spectrometry. The phase I and II metabolism of PTSO was predicted using Meta-Pred Web Server. For the phase I metabolism, rat (male and female) and human liver microsomes were incubated with PTSO and NADPH regeneration system. Furthermore, in the phase II, microsomes were incubated with PTSO and glutathione or uridine 5'- diphosphoglucuronic acid. The analysis revealed the presence of propylpropane thiosulfinate (PTS) originated by redox reaction in phase I, and two conjugates from the phase II: S-propylmercaptoglutathione (GSSP) and S-propylmercaptocysteine (CSSP). Additionally, considering the environmental fate of PTSO and its metabolites, the ADME parameters and the potential ecotoxicity were also predicted using in silico softwares. The results of the ecotoxicity in silico study evidenced that the metabolism induced the formation of detoxified metabolites from the parent compound, except for dimercaprol and 3-mercaptopropane1,2-diol. Further in vivo assays are needed to confirm this prediction.


Assuntos
Allium , Masculino , Ratos , Humanos , Feminino , Animais , Allium/química , Projetos Piloto , Antioxidantes , Microssomos Hepáticos , Cromatografia Líquida de Alta Pressão
3.
Environ Res ; 236(Pt 1): 116682, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37459943

RESUMO

The organosulfur compound propyl-propane thiosulfonate (PTSO), mainly found in Allium cepa, has a promising use in the agrifood industry. To confirm its safety for livestock, consumers, and environment, toxicological assessment is needed. In this regard, endocrine-disrupting chemicals (EDCs) are in the spotlight of research. Therefore, as part of the risk assessment of PTSO, in the present work, an in vivo study was performed in mice exposed to PTSO to investigate its potential reproductive toxicity considering fertility, genetic and endocrine endpoints. Five-weeks-old CD1 mice (80 males, 80 females) were exposed for 11 or 16 weeks (males or females, respectively) to different doses of PTSO (0, 14, 28 and 55 mg PTSO/kg b.w./day; 20 animals per group and sex) through the food pellets. No clinical observations or mortality and no changes in absolute organ weights and relative organ weights/body weight or brain ratios occurred during the study. The estrous cycle did not undergo any significant toxicologically relevant change. Most of the sex hormones displayed normal values. Some alterations in the expression of some genes related to reproduction is only observed in females, but they do not appear to have consequences in the development of sex organs. Docking results showed the impossibility of stable binding to estrogen and androgen receptors. Considering all the results obtained, the safe profile of PTSO can be confirmed for different agrifood applications at the conditions assayed.

4.
Environ Res ; 185: 109284, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32244106

RESUMO

The aim of this study was to optimize the extraction conditions of Microcystin-LR (MC-LR), Microcystin-RR (MC-RR), Microcystin-YR (MC-YR) and Cylindrospermopsin (CYN) simultaneously from mussels by using response surface methodology (RSM) and to validate the method by a dual solid phase extraction (SPE) system combined with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The optimal parameters were: 90% MeOH (% v/v) for the extraction, a solvent/sample ratio of 75 and 15% MeOH in the extract before loading onto SPE. Mussels were spiked at 10; 37.5 and 75 ng g-1 fresh weight (f.w) of the 4 toxins, showing linear ranges of 0.5-75 ng g-1 f.w; low values for the limits of detection (0.01-0.39 ng g-1 f.w.) and quantification (0.23-0.40 ng g-1 f.w.); acceptable recoveries (70.37-114.03%) and relative standard deviation (%RSDIP) values (2.61-13.73%). The method was successfully applied to edible mussels exposed to cyanobacterial extracts under laboratory conditions, and it could allow the monitoring of these cyanotoxins in environmental mussel samples.


Assuntos
Bivalves , Microcistinas , Alcaloides , Animais , Toxinas Bacterianas , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Toxinas de Cianobactérias , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Uracila/análogos & derivados
5.
Environ Res ; 168: 467-489, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30399604

RESUMO

Microcystins (MCs) are hepatotoxins, produced by various species of cyanobacteria, whose occurrence is increasing worldwide owing to climate change and anthropogenic activities. More than 100 variants have been reported, and among them MC-LR is the most extensively studied, but there are other MC congeners that deserve to be investigated. The need for data to characterize the toxicological profile of MC variants other than MC-LR has been identified in order to improve risk assessment in humans and wildlife. Accordingly, the aim of this study was to evaluate the information available in the scientific literature dealing with MC-RR, as this congener is the second most common cyanotoxin in the environment. The review focuses on aspects such as occurrence in water and food, and toxicity studies both in vitro and in vivo. It reveals that, although MC-RR is a real hazard with a high exposure potential in some countries, little is known yet about its specific toxicological properties that differ from those of MC-LR, and important aspects such as genotoxicity and chronic effects have not yet been sufficiently addressed.


Assuntos
Cianobactérias , Poluentes Ambientais/análise , Microcistinas/análise , Poluentes Ambientais/toxicidade , Alimentos , Humanos , Microcistinas/toxicidade , Água
6.
J Toxicol Environ Health A ; 81(12): 525-533, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29537935

RESUMO

Essential oils from Origanum spp. exhibit antioxidant and antimicrobial activities making them suitable for use as food additives. The incorporation of oregano essential oil in active food packaging is under study; however, it has been not authorized for this purpose thus far. In order to fulfill the requirements of the European Food Safety Authority (EFSA), the aim of the present study was to determine the genotoxic potential of oregano essential oil using both the micronucleus (MN) test and comet (standard and enzyme-modified) assays in Wistar rats treated with 50, 100, or 200 mg/kg body weight administered daily for 90 days. MN was performed in cells from the bone marrow and standard and enzyme-modified comet assays were conducted in stomach, liver and blood cells. The major compound detected in the analytical study of oregano essential oil from Origanum vulgare L. virens, was carvacrol (55.82%) followed by thymol (5.14%), as well as their precursors, γ-terpinene (16.39%), and ρ-cimne (4.71%). The results obtained in the genotoxicity assays indicated lack of effect in MN and standard comet assay under the conditions tested. Furthermore, no apparent oxidative damage was observed in the enzyme-modified comet assay in any of the tissues examined of rats exposed to oregano essential oil for 90 days. Therefore, this oregano essential oil appears to be safe in Wistar rats and might be considered as a potential active material in food packaging industry.


Assuntos
Medula Óssea/efeitos dos fármacos , Fígado/efeitos dos fármacos , Óleos Voláteis/farmacologia , Origanum/química , Estômago/efeitos dos fármacos , Administração Oral , Animais , Ensaio Cometa , Feminino , Masculino , Testes para Micronúcleos , Testes de Mutagenicidade , Distribuição Aleatória , Ratos , Ratos Wistar
7.
Ecotoxicology ; 26(1): 22-31, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27770233

RESUMO

Natural toxins produced by freshwater cyanobacteria, such as cylindrospermopsin, have been regarded as an emergent environmental threat. Despite the risks for food safety, the impact of these water contaminants in agriculture is not yet fully understood. Carrots (Daucus carota) are root vegetables, extensively consumed worldwide with great importance for human nourishment and economy. It is, therefore, important to evaluate the possible effects of using water contaminated with cyanotoxins on carrot cultivation. The aim of this work was to investigate cylindrospermopsin effects on D. carota grown in soil and irrigated for 30 days, with a Chrysosporum ovalisporum extract containing environmentally relevant concentrations of cylindrospermopsin (10 and 50 µg/L). The parameters evaluated were plant growth, photosynthetic capacity, and nutritional value (mineral content) in roots of carrots, as these are the edible parts of this plant crop. The results show that, exposure to cylindrospermopsin did not have a clear negative effect on growth or photosynthesis of D. carota, even leading to an increase of both parameters. However, alterations in mineral contents were detected after exposure to crude extracts of C. ovalisporum containing cylindrospermopsin. A general decline was observed for most minerals (Ca, Mg, Na, Fe, Mn, Zn, Mo, and P), although an increase was shown in the case of K and Cu, pointing to a possible interference of the cyanobacterial extract in mineral uptake. This study is the first to evaluate the effects of C. ovalisporum extracts on a root vegetable, however, more research is necessary to understand the effects of this toxin in environmentally relevant scenarios.


Assuntos
Aphanizomenon , Toxinas Bacterianas/toxicidade , Daucus carota/fisiologia , Minerais/metabolismo , Fotossíntese/efeitos dos fármacos , Uracila/análogos & derivados , Poluentes Químicos da Água/toxicidade , Alcaloides , Toxinas de Cianobactérias , Poluentes do Solo/toxicidade , Uracila/toxicidade
8.
Environ Toxicol ; 32(1): 241-254, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26714798

RESUMO

Cylindrospermopsin (CYN) is a cytotoxin highly water-soluble, which is easily taken up by several aquatic organisms. CYN acts as a potent protein and glutathione synthesis inhibitor, as well as inducing genotoxicity, oxidative stress, and histopathological alterations. This is the first study reporting the protective effect of a l-carnitine (LC) pretreatment (400 or 880 mg LC/kg bw fish/day, for 21 days) on the histopathological alterations induced by pure CYN or Aphanizomenon ovalisporum lyophilized cells (400 µg CYN/kg bw fish) in liver, kidney, heart, intestines, and gills of tilapia (Oreochromis niloticus) acutely exposed to the toxin by oral route. The main histopathological changes induced by CYN were disorganized parenchyma with presence of glycogen and lipids in the cytoplasm (liver), glomerulonephritis, glomerular atrophy, and dilatation of Bowman's capsule (kidney), myofibrolysis, loss of myofibrils, with edema and hemorrhage (heart), intestinal villi with necrotic enterocytes and partial loss of microvilli (gastrointestinal tract), and hyperemia and hemorrhage (gills). LC pretreatment was able to totally prevent those CYN-induced alterations from 400 mg LC/kg bw fish/day in almost all organs, except in the heart, where 880 mg LC/kg bw fish/day were needed. In addition, the morphometric study indicated that LC managed to recover totally the affectation in the cross sections of the proximal and distal convoluted tubules in CYN-exposed fish. © 2015 Wiley Periodicals, Inc. Environ Toxicol 32: 241-254, 2017.


Assuntos
Toxinas Bacterianas/toxicidade , Carnitina/farmacologia , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Uracila/análogos & derivados , Poluentes da Água/toxicidade , Alcaloides , Animais , Aphanizomenon/metabolismo , Toxinas Bacterianas/metabolismo , Ciclídeos/metabolismo , Toxinas de Cianobactérias , Dieta , Brânquias/efeitos dos fármacos , Brânquias/patologia , Coração/efeitos dos fármacos , Rim/patologia , Fígado/patologia , Microscopia Eletrônica , Miocárdio/patologia , Estresse Oxidativo/efeitos dos fármacos , Uracila/toxicidade
9.
Environ Toxicol ; 32(4): 1318-1332, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27463828

RESUMO

Cylindrospermopsin (CYN) is a highly water-soluble cytotoxin produced by several species of freshwater cyanobacteria and it is considered the second most studied cyanotoxin worldwide. CYN acts as a potent protein and glutathione synthesis inhibitor, as well as inducing genotoxicity, oxidative stress and histopathological alterations. Studies concerning the depuration of cyanobacterial toxins in aquatic organisms, especially in fish, are of great interest for fish economy and public health, but are scarce in the case of CYN. This is the first study reporting the ability of depuration (3 - 7 days) in reversing or ameliorating the histopathological lesions induced in liver, kidney, heart, intestines, and gills of tilapia (Oreochromis niloticus) due to exposure by immersion to repeated doses of a CYN-containing culture of A. ovalisporum for 14 days. The main histopathological changes induced by CYN were glucogenic degeneration and loss of the normal hepatic cord-structure (liver), hyperemia, dilated Bowman's capsule and cellular tumefaction (kidney), myofibrolysis, hemorrhages and edema (heart), necrosis and partial loss of microvilli (gastrointestinal tract), and hyperemia and inflammatory cells infiltrates (gills). After 3 days of depuration, gills were totally recovered, while the liver, kidney, and gastrointestinal tract required 7 days, and longer depuration periods may be needed for a full recovery of the heart. In addition, the morphometric study indicated that depuration managed to reverse the affectation in the hepatocytes nuclear diameters and cross sections of the proximal and distal convoluted tubules induced in CYN-exposed fish. In general, these results validate depuration as an effective practice for detoxification of fish contaminated with CYN. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1318-1332, 2017.


Assuntos
Toxinas Bacterianas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Uracila/análogos & derivados , Alcaloides , Animais , Cianobactérias/metabolismo , Toxinas de Cianobactérias , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Brânquias/patologia , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Intestinos/patologia , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Tilápia , Uracila/toxicidade
10.
Environ Toxicol ; 31(11): 1469-1485, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26011011

RESUMO

Cylindrospermopsin (CYN) is a cyanotoxin frequently involved in blooms with a predominantly extracellular availability, which makes it easily taken up by a variety of aquatic organisms. CYN is a potent protein and glutathione synthesis inhibitor, and also induces genotoxicity, oxidative stress and several histopathological lesions. The present study investigates the protective role of a vitamin E pretreatment (700 mg vit E/kg fish bw/day, for 7 days) on the histopathological alterations induced in different organs of tilapia (Oreochromis niloticus) acutely exposed to a single oral dose of 400 µg pure CYN/kg bw fish. The major histological changes observed were degenerative glucogenic process and loss of the hepatic structure in the liver, glomerulopathy and tubular tumefaction in the kidney, myofibrolysis and edema in the heart, catarrhal enteritis and necrosis in the gastrointestinal tract, hyperemic processes in the gill lamellae, and high basophilia, degeneration and tumefaction of granular neurons in the brain. Vitamin E pretreatment was effective in preventing or ameliorating the abovementioned alterations induced by CYN. In addition, a morphometric study indicated that the average nuclear diameter of hepatocytes, and cross-sections of proximal and distal convoluted tubules, together with the cardiac fiber and capillaries diameters represent a useful tool to evaluate the damage induced by CYN. This is the first study reporting vitamin E prevention of histopathological damage in tissues (liver, kidney, heart, gastrointestinal tract, gills and brain) of fish intoxicated with CYN. Therefore, vitamin E can be considered a useful chemoprotectant in the treatment of histopathological changes induced in CYN-intoxicated fish. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1469-1485, 2016.


Assuntos
Toxinas Bacterianas/antagonistas & inibidores , Ciclídeos , Citoproteção , Hepatócitos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Uracila/análogos & derivados , Vitamina E/farmacologia , Alcaloides , Animais , Toxinas Bacterianas/toxicidade , Ciclídeos/anatomia & histologia , Ciclídeos/metabolismo , Toxinas de Cianobactérias , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Hepatócitos/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/metabolismo , Masculino , Estresse Oxidativo/efeitos dos fármacos , Fatores de Tempo , Testes de Toxicidade , Uracila/antagonistas & inibidores , Uracila/toxicidade
11.
J Sci Food Agric ; 96(9): 3207-12, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26478463

RESUMO

BACKGROUND: Environmental, economic and safety challenges motivate shift towards safer materials for food packaging. New bioactive packaging techniques, i.e. addition of essential plant oils (EOs), are gaining attention by creating barriers to protect products from spoilage. Analytical pyrolysis gas chromatography-mass spectrometry (Py-GC-MS) was used to fingerprint a bioactive polylactic acid (PLA) with polybutylene succinate (PBS) (950 g kg(-1) :50 g kg(-1) ) film extruded with variable quantities (0, 20, 50 and 100 g kg(-1) ) of Origanum vulgare EO. RESULTS: Main PLA:PBS pyrolysis products were lactide enantiomers and monomer units from the major PLA fraction and succinic acid anhydride from the PBS fraction. Oregano EO pyrolysis released cymene, terpinene and thymol/carvacrol peaks as diagnostic peaks for EO. In fact, linear correlation coefficients better than 0.950R(2) value (P < 0.001) were found between the chromatographic area of the diagnostic peaks and the amount of oregano EO in the bioplastic. CONCLUSION: The pyrolytic behaviour of a bio-based active package polymer including EO is studied in detail. Identified diagnostic compounds provide a tool to monitor the quantity of EO incorporated into the PLA:PBS polymeric matrix. Analytical pyrolysis is proposed as a rapid technique for the identification and quantification of additives within bio-based plastic matrices. © 2015 Society of Chemical Industry.


Assuntos
Embalagem de Alimentos , Óleos Voláteis/química , Origanum/química , Butileno Glicóis/química , Cimenos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Monoterpenos/química , Extratos Vegetais/química , Poliésteres/química , Polímeros/química , Ácido Succínico/química , Timol/química
12.
Environ Res ; 138: 233-54, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25732897

RESUMO

Clays and clay minerals are widely used in many facets of our society. This review addresses the main clays of each phyllosilicate groups, namely, kaolinite, montmorillonite (Mt) and sepiolite, placing special emphasis on Mt and kaolinite, which are the clays that are more frequently used in food packaging, one of the applications that are currently exhibiting higher development. The improvements in the composite materials obtained from clays and polymeric matrices are remarkable and well known, but the potential toxicological effects of unmodified or modified clay minerals and derived nanocomposites are currently being investigated with increased interest. In this sense, this work focused on a review of the published reports related to the analysis of the toxicological profile of commercial and novel modified clays and derived nanocomposites. An exhaustive review of the main in vitro and in vivo toxicological studies, antimicrobial activity assessments, and the human and environmental impacts of clays and derived nanocomposites was performed. From the analysis of the scientific literature different conclusions can be derived. Thus, in vitro studies suggest that clays in general induce cytotoxicity (with dependence on the clay, concentration, experimental system, etc.) with different underlying mechanisms such as necrosis/apoptosis, oxidative stress or genotoxicity. However, most of in vivo experiments performed in rodents showed no clear evidences of systemic toxicity even at doses of 5000mg/kg. Regarding to humans, pulmonary exposure is the most frequent, and although clays are usually mixed with other minerals, they have been reported to induce pneumoconiosis per se. Oral exposure is also common both intentionally and unintentionally. Although they do not show a high toxicity through this pathway, toxic effects could be induced due to the increased or reduced exposure to mineral elements. Finally, there are few studies about the effects of clay minerals on wildlife, with laboratory trials showing contradictory outcomes. Clay minerals have different applications in the environment, thus with a strict control of the concentrations used, they can provide beneficial uses. Despite the extensive number of reports available, there is also a need of systematic in vitro-in vivo extrapolation studies, with still scarce information on toxicity biomarkers such as inmunomodulatory effects or alteration of the genetic expression. In conclusion, a case by case toxicological evaluation is required taking into account that different clays have their own toxicological profiles, their modification can change this profile, and the potential increase of the human/environmental exposure to clay minerals due to their novel applications.


Assuntos
Silicatos de Alumínio/toxicidade , Minerais/toxicidade , Nanocompostos/toxicidade , Animais , Bentonita/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Argila , Embalagem de Alimentos , Humanos , Caulim/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Roedores
13.
Toxicol Mech Methods ; 25(6): 440-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26156198

RESUMO

CONTEXT: The accumulation of chronic or severe acute DNA and cellular damage in oral mucosa cells is one of the main factors that help initiate a wide range of malignant lesions in the oral cavity. There has been considerable controversy in the literature about the effect of such sustained genotoxic and cytotoxic damage to oral mucosa cells. OBJECTIVE: The aim of this systematic review, reported in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, is to investigate the effects of such interventions. METHODS: Electronic and manual searches were performed (15 May 2015) for Randomized Clinical Trials/quasi-Randomized Clinical Trials that analyzed the genotoxic/cytotoxic effects of these types of oral appliances in humans. A primary outcome (cell/DNA damage) and a number of secondary outcomes were examined. Two reviewers carried out the study selection and performed a "risk of bias" assessment [Cochrane Collaboration's tool]. Wherever possible the meta-analysis was conducted on homogenous groups. RESULTS: From the electronic search (2797), 6 studies met the eligibility criteria. Most studies (5/6) observed significant differences in most comparisons at the short-term (1-3 months) and long-term (24-48 months) evaluations, with respect to critically acute genotoxic/cytotoxic effects. Some of the studies (2/3) concluded that the post-removable effects at DNA/cellular levels were not significant (p > 0.05) with respect to the controls. CONCLUSIONS: Acute DNA/cellular damage in oral mucosa cells is induced by orthodontic appliances. Nevertheless, even though these effects were no longer detected after removing the appliances, more rigorous RCTs are needed to explore the extent to which acquired damage can be observed in the oral mucosa.


Assuntos
Dano ao DNA , Materiais Dentários/efeitos adversos , Células Epiteliais/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Metais/efeitos adversos , Mucosa Bucal/efeitos dos fármacos , Aparelhos Ortodônticos/efeitos adversos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Humanos , Mucosa Bucal/metabolismo , Mucosa Bucal/patologia , Medição de Risco , Fatores de Tempo
14.
Toxicol Mech Methods ; 25(6): 487-93, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26062010

RESUMO

Miniscrew implants are widely used nowadays in orthodontic treatments due to their good results in clinical practice. However, data regarding the biocompatibility of commercially available orthodontic miniscrews and temporary devices are very scarce, and their role as genotoxicity inducers has been not previously evaluated with the alkaline comet assay. The aim of this study was to investigate the DNA damage in buccal cells of patients subjected to orthodontic treatments. The alkaline comet assay has been applied in oral mucosa cells from patients treated with conventional orthodontic treatment in comparison to patients treated additionally with miniscrews, non-treated volunteers (control) and smoking volunteers (positive control). The application of orthodontic appliances and miniscrews induced significant and similar (2-fold) increases of %DNA in tail in comparison to control group. Females experienced a significant increase in %DNA in all the treatments in comparison to the control group, whereas males showed significant damage only with the combined orthodontic and miniscrew treatment. In conclusion, conventional orthodontic appliances induced genotoxicity, and the incorporation of miniscrews assayed did not imply any additional increase of DNA damage.


Assuntos
Parafusos Ósseos/efeitos adversos , Ensaio Cometa , Dano ao DNA , Células Epiteliais/efeitos dos fármacos , Metais/efeitos adversos , Mucosa Bucal/efeitos dos fármacos , Procedimentos de Ancoragem Ortodôntica/efeitos adversos , Procedimentos de Ancoragem Ortodôntica/instrumentação , Adolescente , Adulto , Criança , Células Epiteliais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/patologia , Medição de Risco , Adulto Jovem
15.
J Toxicol Environ Health A ; 77(8): 456-66, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24627999

RESUMO

Although clays are wildly used in a range of applications, the toxicity assessment of these new materials is still scarce. In the present study, oxidative stress induced by Clay 1, a novel clay, was determined in rats after 90 d of oral exposure. The activities of antioxidant enzymes, namely, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione S-transferase (GST), were examined. In addition, genetic expressions of SOD and CAT and relative protein abundance of CAT were also determined. Data showed that most of the biomarkers assayed remained unaltered. Only CAT activity, as well as its genetic and protein expressions, appeared enhanced in the kidney. Therefore, further studies are needed to clarify the relevance and consequences of these findings to ensure the safety of this clay.


Assuntos
Silicatos de Alumínio/toxicidade , Contaminação de Alimentos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Rim/efeitos dos fármacos , Nanopartículas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Oxirredutases/metabolismo , Administração Oral , Silicatos de Alumínio/administração & dosagem , Silicatos de Alumínio/química , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Catalase/biossíntese , Catalase/genética , Catalase/metabolismo , Argila , Indução Enzimática/efeitos dos fármacos , Embalagem de Alimentos , Rim/enzimologia , Rim/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Masculino , Nanopartículas/administração & dosagem , Nanopartículas/química , Oxirredutases/genética , Distribuição Aleatória , Ratos , Ratos Wistar , Testes de Toxicidade Subcrônica
16.
J Appl Toxicol ; 34(6): 714-25, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24122917

RESUMO

The incorporation of the natural mineral clay montmorillonite into polymeric systems enhances their barrier properties as well as their thermal and mechanical resistance, making them suitable for a wide range of industrial applications, e.g., in the food industry. Considering humans could easily be exposed to these clays due to migration into food, toxicological and health effects of clay exposure should be studied. In the present work, the cytotoxic effects induced by two different clays (the unmodified clay Cloisite(®) Na(+) , and the organically modified Cloisite(®) 30B) on Caco-2 cells were studied after 24 and 48 h of exposure. The basal cytotoxicity endpoints assessed were total protein content, neutral red uptake and a tetrazolium salt reduction. Our results showed that only Cloisite(®) 30B induced toxic effects. Therefore, the effects of subcytotoxic concentrations of this clay on the generation of intracellular reactive oxygen species, glutathione content and DNA damage (comet assay) were investigated. Results indicate that oxidative stress may be implicated in the toxicity induced by Closite(®) 30B, in regards of the increases in intracellular reactive oxygen species production and glutathione content at the highest concentration assayed, while no damage was observed in DNA. The most remarkable morphological alterations observed were dilated cisternae edge in the Golgi apparatus and nucleolar segregation, suggesting impairment in the secretory functions, which could be related to inhibition in the synthesis of proteins.


Assuntos
Silicatos de Alumínio/toxicidade , Bentonita/toxicidade , Colo/efeitos dos fármacos , Células CACO-2 , Nucléolo Celular/metabolismo , Nucléolo Celular/ultraestrutura , Forma Celular/efeitos dos fármacos , Argila , Colo/metabolismo , Colo/ultraestrutura , Dano ao DNA , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Complexo de Golgi/efeitos dos fármacos , Complexo de Golgi/metabolismo , Complexo de Golgi/ultraestrutura , Humanos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Fatores de Tempo
17.
Environ Toxicol ; 29(4): 371-85, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22331699

RESUMO

Cylindrospermopsin (CYN) is increasingly recognized as a potential threat to drinking water safety, due to its ubiquity. This cyanotoxin has been found to cause toxic effects in mammals, and although fish could be in contact with this toxin, acute toxicity studies on fish are nonexistent. This is the first study showing that single doses of CYN pure standard (200 or 400 µg CYN/kg fish bw) by oral route (gavage) generate histopathological effects in fish (Tilapia-Oreochromis niloticus) exposed to the toxin under laboratory condition. Among the morphological changes, disorganized parenchymal architecture in the liver, dilated Bowman's space in the kidney, fibrolysis in the heart, necrotic enteritis in the intestines, and hemorrhages in the gills, were observed. Moreover, some oxidative stress biomarkers in the liver and kidney of tilapias were altered. Thus, CYN exposure induced increased protein oxidation products in both organs, NADPH oxidase activity was significantly increased with the kidney being the most affected organ, and decreased GSH contents were also detected in both organs, at the higher dose assayed.


Assuntos
Estresse Oxidativo/efeitos dos fármacos , Tilápia/anatomia & histologia , Tilápia/metabolismo , Toxinas Biológicas/toxicidade , Uracila/análogos & derivados , Alcaloides , Animais , Toxinas Bacterianas , Biomarcadores/metabolismo , Toxinas de Cianobactérias , Brânquias/efeitos dos fármacos , Brânquias/patologia , Glutationa/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Miocárdio/patologia , NADPH Oxidases/metabolismo , Oxirredução , Uracila/toxicidade
18.
Toxins (Basel) ; 16(4)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38668623

RESUMO

Anatoxin-a (ATX-a) is a potent neurotoxin produced by several species of cyanobacteria whose exposure can have direct consequences, including neurological disorders and death. The increasing prevalence of harmful cyanobacterial blooms makes the detection and reliable assessment of ATX-a levels essential to prevent the risk associated with public health. Therefore, the aim of this review is to compile the analytical methods developed to date for the detection and quantification of ATX-a levels alone and in mixtures with other cyanotoxins and their suitability. A classification of the analytical methods available is fundamental to make an appropriate choice according to the type of sample, the equipment available, and the required sensitivity and specificity for each specific purpose. The most widely used detection technique for the quantification of this toxin is liquid chromatography-tandem mass spectrometry (LC-MS/MS). The analytical methods reviewed herein focus mainly on water and cyanobacterial samples, so the need for validated analytical methods in more complex matrices (vegetables and fish) for the determination of ATX-a to assess dietary exposure to this toxin is evidenced. There is currently a trend towards the validation of multitoxin methods as opposed to single-ATX-a determination methods, which corresponds to the real situation of cyanotoxins' confluence in nature.


Assuntos
Toxinas de Cianobactérias , Cianobactérias , Espectrometria de Massas em Tandem , Tropanos , Tropanos/análise , Cromatografia Líquida , Cianobactérias/química , Animais , Humanos , Contaminação de Alimentos/análise
19.
Phytomedicine ; 130: 155731, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38824824

RESUMO

BACKGROUND: Sulforaphane (SFN) is a dietary isothiocyanate, derived from glucoraphanin, present in cruciferous vegetables belonging to the Brassica genus. It is a biologically active phytochemical that acts as a nuclear factor erythroid 2-related factor 2 (Nrf2) inducer. Thus, it has been reported to have multiple protective functions including anticancer responses and protection against a toxic agent's action. PURPOSE: The present work systematically reviewed and synthesised the protective properties of sulforaphane against a toxic agent. This review reveals the mechanism of the action of SFN in each organ or system. METHODS: The PRISMA guideline was followed in this sequence: researched literature, organised retrieved documents, abstracted relevant information, assessed study quality and bias, synthesised data, and prepared a comprehensive report. Searches were conducted on Science Direct and PubMed using the keywords "Sulforaphane" AND ("protective effects" OR "protection against"). RESULTS: Reports showed that liver and the nervous system are the target organs on which attention was focused, and this might be due to the key role of oxidative stress in liver and neurodegenerative diseases. However, protective activities have also been demonstrated in the lungs, heart, immune system, kidneys, and endocrine system. SFN exerts its protective effects by activating the Nrf2 pathway, which enhances antioxidant defenses and reduces oxidative stress. It also suppresses inflammation by decreasing interleukin production. Moreover, SFN inhibits apoptosis by preventing caspase 3 cleavage and increasing Bcl2 levels. Overall, SFN demonstrates multifaceted mechanisms to counteract the adverse effects of toxic agents. CONCLUSION: SFN has potential clinical applications as a chemoprotective agent. Nevertheless, more studies are necessary to set the safe doses of SFN in humans.


Assuntos
Isotiocianatos , Sulfóxidos , Isotiocianatos/farmacologia , Sulfóxidos/farmacologia , Humanos , Animais , Brassica/química , Estresse Oxidativo/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Substâncias Protetoras/farmacologia
20.
Antioxidants (Basel) ; 13(3)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38539883

RESUMO

Propyl-propane thiosulfonate (PTSO), an antioxidant organosulfur compound present in the genus Allium, has become a potential natural additive for food and feed, as well as a possible biopesticide for pest control in plants. A toxicological assessment is necessary to verify its safety for livestock, consumers, and the environment. As part of the risk assessment of PTSO, this study was designed to explore its potential reproductive toxicity in mice following the OECD 416 guideline. The investigation spans two generations to comprehensively evaluate potential reproductive, teratogenic, and hereditary effects. A total of 80 CD1 mice per sex and generation were subjected to PTSO exposure during three phases (premating, gestation, and lactation). This evaluation encompassed three dose levels: 14, 28, and 55 mg PTSO/kg b.w./day, administered through the feed. No clinical changes or mortality attributed to the administration of PTSO were observed in the study. Some changes in the body weight and food consumption were observed, but not related to sex or in a dose-dependent manner. The two parental generations (F0, F1) exhibited normal reproductive performance, and the offspring (F1 and F2) were born without any abnormalities. The serum sexual hormone levels (progesterone -P-, testosterone -T-, estradiol -E2-, follicular stimulating hormone -FSH-, and luteinizing hormone -LH-) were in a normal range. Although significant changes were observed in the sperm analysis in the case of F0 group, no variation was found for F1 group, and no alterations in fertility were recorded either. The absolute organ weights and relative organ weight/body weight and organ weight/brain weight ratios, and the complete histopathological study, showed no significant alterations in males and females for all the generations considered. Considering all the results obtained, PTSO is not considered a reproductive or developmental toxicant in mice under the assayed conditions. These results support the good safety profile of PTSO for its potential application in the agrifood sector.

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