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1.
Environ Res ; 228: 115906, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37062480

RESUMO

Wide-scale emergence of glyphosate-resistant weeds has led to an increase in the simultaneous application of herbicide mixtures exacerbated by the introduction of crops tolerant to glyphosate plus dicamba or glyphosate plus 2,4-D. This raises serious concerns regarding the environmental and health risks resulting from increased exposure to a mixture of herbicide active ingredients. We evaluated hepatotoxic effects following perinatal exposure to glyphosate alone or in combination with 2,4-D and dicamba from gestational day-6 until adulthood in Wistar rats. Animals were administered with glyphosate at the European Union (EU) acceptable daily intake (ADI; 0.5 mg/kg bw/day) and no-observed-adverse-effect level (NOAEL; 50 mg/kg bw/day). A mixture of glyphosate with 2,4-D (0.3 mg/kg bw/day) and dicamba (0.02 mg/kg bw/day) with each at their EU ADI was evaluated. Redox status was determined by measuring levels of reduced glutathione, decomposition rate of Η2Ο2, glutathione reductase, glutathione peroxidase, total antioxidant capacity, thiobarbituric reactive substances, and protein carbonyls. Gene expression analysis of Nr1d1, Nr1d2, Clec2g, Ier3, and Gadd45g associated with oxidative damage to DNA, was also performed. Analysis of liver samples showed that exposure to the mixture of the three herbicides induced a marked increase in the concentration of glutathione and malondialdehyde indicative of a disturbance in redox balance. Nevertheless, the effect of increased lipid peroxidation was not discernible following a 3-month recuperation period where animals were withdrawn from pesticide exposure post-weaning. Interestingly, toxic effects caused by prenatal exposure to the glyphosate NOAEL were present after the same 3-month recovery period. No statistically significant changes in the expression of genes linked with genotoxicity were observed. Our findings reinforce the importance of assessing the combined effects of chemical pollutants at doses that are asserted by regulatory agencies to be safe individually.


Assuntos
Dicamba , Herbicidas , Ratos , Animais , Gravidez , Feminino , Dicamba/química , Dicamba/toxicidade , Ratos Wistar , Herbicidas/toxicidade , Herbicidas/química , Oxirredução , Ácido 2,4-Diclorofenoxiacético , Fígado , Glifosato
2.
Molecules ; 28(4)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36838560

RESUMO

Wine and by-products of the winemaking process, such as grape stems, are rich in bioactive polyphenolic compounds that might be beneficial for animal and human health. In recent years, the administration of dietary polyphenols with strong antioxidant and cytoprotective properties has constituted an emerging line of research interest toward disease prevention. However, in scientific literature, only a limited number of studies have investigated the safety and the toxicological risks of polyphenolic compounds in vivo. Based on the above, the purpose of the present study was two-fold: first, to examine the effects of oral administration of a grape stem extract, derived from the Greek red wine Mavrodaphne, on mice redox biomarkers; and second, to investigate the biological effects of oral administration of a wine extract, derived from the emblematic Greek red wine Xinomavro, on rats. Toward this purpose, body weight, growth rate, hematological, biochemical, and histopathological parameters, as well as a panel of redox biomarkers, were examined. According to our results, the administration of Mavrodaphne grape stem extract in mice induced alterations in redox homeostasis, preventing mice from the adverse effects of lipid peroxidation. Contrariwise, the administration of Xinomavro wine extract induced both beneficial and harmful outcomes on rat redox status determined by the examined tissue. Collectively, our study reports that the Mavrodaphne grape stem extract, a serious pollutant when disposed in environmental matrices, is an important source of bioactive polyphenolic compounds that could protect from oxidative damage and improve animal and human health. Finally, the Xinomavro wine extract exerts tissue-specific changes in redox balance, which are indicative of the complexity that characterizes the biological systems.


Assuntos
Vitis , Vinho , Ratos , Camundongos , Humanos , Animais , Vinho/análise , Vitis/química , Polifenóis/química , Oxirredução , Antioxidantes/farmacologia , Administração Oral , Biomarcadores , Extratos Vegetais/química
3.
Int J Mol Sci ; 23(1)2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-35008472

RESUMO

Cellular adaptive mechanisms emerging after exposure to low levels of toxic agents or stressful stimuli comprise an important biological feature that has gained considerable scientific interest. Investigations of low-dose exposures to diverse chemical compounds signify the non-linear mode of action in the exposed cell or organism at such dose levels in contrast to the classic detrimental effects induced at higher ones, a phenomenon usually referred to as hormesis. The resulting phenotype is a beneficial effect that tests our physiology within the limits of our homeostatic adaptations. Therefore, doses below the region of adverse responses are of particular interest and are specified as the hormetic gain zone. The manifestation of redox adaptations aiming to prevent from disturbances of redox homeostasis represent an area of particular interest in hormetic responses, observed after exposure not only to stressors but also to compounds of natural origin, such as phytochemicals. Findings from previous studies on several agents demonstrate the heterogeneity of the specific zone in terms of the molecular events occurring. Major factors deeply involved in these biphasic phenomena are the bioactive compound per se, the dose level, the duration of exposure, the cell, tissue or even organ exposed to and, of course, the biomarker examined. In the end, the molecular fate is a complex toxicological event, based on beneficial and detrimental effects, which, however, are poorly understood to date.


Assuntos
Hormese/fisiologia , Toxicologia/métodos , Adaptação Fisiológica/fisiologia , Animais , Biomarcadores/metabolismo , Humanos , Oxirredução
4.
Cytojournal ; 9: 16, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22919423

RESUMO

Primary effusion lymphoma (PEL) is an unusual, human herpes virus-8 (HHV-8)-associated type of lymphoma, presenting as lymphomatous effusion in body cavities, without a detectable tumor mass. It primarily affects human immunodeficiency virus (HIV)-infected patients, but has also been described in other immunocompromised individuals. Although PEL is a B-cell lymphoma, the neoplastic cells are usually of the 'null' phenotype by immunocytochemistry. This report describes a case of PEL with T-cell phenotype in a HIV-negative patient and reviews all the relevant cases published until now. Our patient suffered from cirrhosis associated with Hepatitis B virus (HBV) infection and presented with a large ascitic effusion, in the absence of peripheral lymphadenopathy or solid mass within either the abdomen or the thorax. Paracentesis disclosed large lymphoma cells with anaplastic features consisting of moderate cytoplasm and single or occasionally multiple irregular nuclei with single or multiple prominent nucleoli. Immunocytochemically, these cells were negative for both CD3 and CD20, but showed a positive reaction for T-cell markers CD43 and CD45RO (VCHL-1). Furthermore, the neoplastic cells revealed strong positivity for EMA and CD30, but they lacked expression of ALK-1, TIA-1, and Perforin. The immune status for both HHV-8 and Epstein-Barr virus (EBV) was evaluated and showed positive immunostaining only for the former. The combination of the immunohistochemistry results with the existence of a clonal rearrangement in the immunoglobulin heavy chain gene (identified by PCR), were compatible with the diagnosis of PEL. The presence of T-cell markers was consistent with the diagnosis of PEL with an aberrant T-cell phenotype.

5.
Toxicol Rep ; 7: 501-509, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32337162

RESUMO

Fungicides are used in the agricultural sector against the harmful action of fungi, however they are potential toxic agents for the environment and the living organisms. Benomyl is a widely encountered benzimidazole fungicide that exerts its toxicity via inhibiting microtubule formation in the nervous system and the male reproductive and endocrine systems, whilst it is a known teratogen. Since toxic effects of benomyl and its molecular mechanisms are not fully understood, we aimed to detect its neurotoxic potential via evaluating cytotoxicity, oxidative stress and apoptosis in SH-SY5Y cell line. The cells were incubated with benomyl in a concentration range between 1 and 6 µM for 24 h. Our results indicated a concentration-dependent enhancement of reactive oxygen species measured through flow cytometry and DNA damage evaluated via the comet assay. Additionally, it induced apoptosis in all tested concentrations. According to the findings of the present study, benomyl is a xenobiotic, which it appears to exert its toxic action via a redox-related mechanism that, finally, induces cell apoptosis and death. We believe that this study will offer further insight in the toxicity mechanism of benomyl, although further studies are recommended in order to elucidate these mechanisms in the molecular level.

6.
Food Chem Toxicol ; 142: 111508, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32544564

RESUMO

Whey protein, a by-product of cheese industry, is harmful for the environment (i.e., surface and subterranean waters, soil) and, therefore, for humans due to its high polluting burden. Concomitantly, it has been reported that it is a mixture with potent antioxidant action since it is rich in cysteine residues, which are necessary for glutathione synthesis in vivo. On this basis, this study intended to examine the role of whey protein on the intensification of tissue antioxidant arsenal. To this end, a dose of sheep/goat whey protein equal to 1 g/kg of body weight/day dissolved in drinking water was administered to rats for 28 consecutive days. According to our findings, whey protein improved the antioxidant profile of liver, small intestine, lung and muscle whereas it did not affect the redox state of kidney. Our results were based on the alterations found in the protein expression of glutamate cysteine ligase, catalase and superoxide dismutase-1 measured in all tissues and the activity of glutathione S-transferase evaluated in muscle. Although tissue-specific, it is obvious that the action of whey protein is biologically beneficial and could serve as a biofunctional constituent for foods able to improve redox profile when administered against redox-related diseases.


Assuntos
Antioxidantes/farmacologia , Enzimas/metabolismo , Proteínas do Soro do Leite/farmacologia , Animais , Cabras , Masculino , Oxirredução , Ratos , Ratos Wistar , Ovinos
7.
In Vivo ; 34(4): 1811-1821, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606151

RESUMO

BACKGROUND/AIM: Olive mill wastewater (OMW) is a byproduct of olive oil production. The aim of the study was to estimate the redox profile of lambs' vital organs after consumption of an OMW-supplemented feed. MATERIALS AND METHODS: Twenty-four lambs received breast milk until day 15. Then, they were divided in two groups: control and OMW, n=12 each. The control group received standard ration, while the OMW group received OMW enriched feed along with mother's milk until day 42 and animals (n=6 per group) were sacrificed. The remaining 12 received the feeds until day 70 and sacrificed. Tissue samples were collected at day 42 and 70 and specific redox biomarkers were assessed. RESULTS: Overall, the OMW feed improved tissue redox profile by affecting the glutathione S-transferase (GST) activity and γ-glutamate-cysteine ligase (γ-GCL) expression in all tested tissues. Superoxide dismutase (SOD) activity was not affected. CONCLUSION: The polyphenol-rich byproduct reinforced lamb redox profile and may putatively improve their wellness and productivity.


Assuntos
Antioxidantes , Olea , Animais , Suplementos Nutricionais , Feminino , Humanos , Resíduos Industriais , Azeite de Oliva , Oxirredução , Ovinos , Águas Residuárias
8.
Toxicol Rep ; 7: 421-432, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32140426

RESUMO

Olive oil (OO) possesses a predominant role in the diet of Mediterranean countries. According to a health claim approved by the European Food Safety Authority, OO protects against oxidative stress­induced lipid peroxidation in human blood, when it contains at least 5 mg of hydroxytyrosol and its derivatives per 20 g. However, studies regarding the effects of a total OO biophenols on redox status in vivo are scarce and either observational and do not provide a holistic picture of their action in tissues. Following a series of in vitro screening tests an OO containing biophenols at 800 mg/kg of OO was administered for 14 days to male Wistar rats at a dose corresponding to 20 g OO/per day to humans. Our results showed that OO reinforced the antioxidant profile of blood, brain, muscle and small intestine, it induced oxidative stress in spleen, pancreas, liver and heart, whereas no distinct effects were observed in lung, colon and kidney. The seemingly negative effects of OO follow the recently formulated idea in toxicology, namely the real life exposure scenario. This study reports that OO, although considered a nutritional source rich in antioxidants, it exerts a tissues specific action when administered in vivo.

9.
Exp Ther Med ; 19(3): 1626-1632, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32104213

RESUMO

Osteoarthritis (OA) and osteoporosis (OP) are associated skeletal pathologies and have as a distinct feature the abnormal reconstruction of the subchondral bone. OA and OP have been characterized as age-related diseases and have been associated with telomere shortening and altered telomerase activity (TA). This review discusses the role of telomeres and telomerase in OA and OP pathologies and focuses on the usability of telomere length (TL) and the rate of telomere shortening as potential disease biomarkers. A number of studies have demonstrated that telomere shortening may contribute to OA and OP as an epigenetic factor. Therefore, it has been claimed that the measurement of TL of chondrocytes and/or peripheral blood cells may be an appropriate marker for the evaluation of the progression of these diseases. However, there is a need to be perform further studies with larger cohorts, with the aim of obtaining objective results and a better understanding of the association between TL, inflammation and aging, in order to provide further insight into the pathophysiology of degenerative joint diseases.

10.
Mol Clin Oncol ; 12(3): 258-262, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32064103

RESUMO

Localized amyloidosis is a rare condition characterized by the deposition of misfolding protein in a tissue, without other systemic manifestations. Only a small number of cases of localized amyloidosis of the tongue have been reported to date, in contrast to systemic amyloidosis, in which localization on the tongue is common. This study presents a rare case of localized amyloidosis of the tongue (amyloidoma) and provides a summary of the known literature of localized amyloidosis. This study describes the case of a 36-year-old female who presented with a swelling of the tongue base. The diagnosis of amyloidoma was made based on the findings of the physical examination, head and neck MRI findings and the histopathological examination with Congo red stain under polarized light. The histopathological diagnosis was as follows: Localized lambda light-chain amyloidosis. A thorough physical examination was performed by the ENT and Hematology/Oncology departments, without revealing signs of systemic disease. A series of hematological and imaging tests were also performed to verify that there was no sign of systemic involvement. The patient declined surgical excision and the 2-year follow-up did not reveal any changes in tumor dimension. Although the etiology of localized amyloidosis is yet not clear, the prolonged reaction of tissue plasma cells to environmental antigens may be a causative factor for the initiation of the neoplastic process.

11.
Acta Cytol ; 53(4): 423-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19697728

RESUMO

BACKGROUND: Malignant peripheral nerve sheath tumor (MPNST) is an uncommon mesenchymal neoplasm showing nerve sheath differentiation, usually arising in large nerves of the trunk and extremities. Primary location in the parotid gland is rare. We describe fine needle aspiration (FNA) findings in a case of MPNST in the parotid gland. Differential diagnostic problems encountered in interpretation are discussed. CASE: A 39-year-old man underwent FNA of a well-circumscribed, painless, mobile mass of the parotid gland. Smears were cellular, with clusters of tightly packed spindle or oval cells arranged in a storiform or whorled pattern, showing clearly malignant features. Elongated nuclei with tapered ends and many angulated nuclei were encountered. The background contained abundant necrotic material with dispersed malignant nuclei. Neoplastic cells were positive for vimentin and weakly positive for S-100 and negative for cytokeratins 8 and 18 and HMB-45. Cytologic diagnosis was positive for malignant cells consistent with a spindle cell sarcoma, with morphologic features compatible to neural differentiation, confirmed by histologic examination. CONCLUSION: This case illustrates that attention to moiphologic criteria suggestive of nerve sheath phenotype supported by immunocytochemical data is extremely helpful and reliable in the diagnostic approach to MPNSTs, even in rare locations.


Assuntos
Biópsia por Agulha Fina , Neoplasias de Bainha Neural/patologia , Neoplasias Parotídeas/patologia , Adulto , Diagnóstico Diferencial , Humanos , Masculino
13.
Biomed Rep ; 8(5): 417-425, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29732146

RESUMO

Oxidative stress is linked to coronary artery disease and is a major mechanism in contrast-induced nephropathy. Trans-radial approach in coronary angiography (CA) with minimized peri-procedural bleeding is expected to reduce acute kidney injury incidence. In the present study, oxidative stress patterns observed in radial CA and their associations with early manifestations of kidney injury are described. A total of 20 stable coronary disease patients submitted to CA and 17 sex-matched patients undergoing computed tomography for myoskeletal reasons were enrolled. Reduced glutathione, catalase, thiobarbituric acid reactive species (TBARS) levels and total anti-oxidant status were measured at various time points postangiography. In ischemic patients baseline TBARS levels were 2-fold lower compared to controls, while carbonyls levels were 35% higher. Glutathione was almost 4-fold lower than the control group. Glutathione and lipid peroxidation in ischemic patients gradually increased after contrast medium administration and reached 180% (P<0.001) and 20% (P=0.021) after 4-6 h, respectively. Four patients presented early evidence of contrast-induced nephropathy postangiography, while no control patient developed acute kidney injury. In the multiple logistic regression analysis, only the creatinine levels at baseline influenced the frequency of early contrast-induced nephropathy development (ß =0.36, 95% CI: 0.285-0.438, P=0.01). Glutathione low levels were dominant in the baseline values of ischemic patients who developed contrast-induced nephropathy. Glutathione levels rapidly increased while protein oxidation decreased at the expense of lipid peroxidation. In conclusion, early oxidative stress changes occur in trans-radial CA patients with a mild profile, sufficient to mobilize patient antioxidant defenses.

14.
Food Chem Toxicol ; 108(Pt A): 186-193, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28774741

RESUMO

Contrast-induced nephropathy (CIN) is a leading cause of hospital-acquired acute kidney injury as a result of iodinated contrast-media use for diagnostic purposes. Pathophysiology remains unclear. In the present study iopromide was administered to New Zealand white rabbits without any prior intervention. Oxidative stress was assessed in blood and tissue level at three anatomical kidney areas (medullary, cortical, juxtamedullary). Histopathological evaluation was also performed. Serum creatinine and urea increased in the CIN groups over 25% at two hours after administration and returned to baseline at 48 h. In kidney tissues, a significant reduction (40%) of catalase in renal cortexes of the CIN groups was observed. Necrosis and tubular vacuolization was also noted that correlated with urea and creatinine levels. Lipid peroxidation decreased at 10 h after administration (>45%) and remained low even at 48 h. Plasma protein carbonyls were significantly increased (67%) in 2 h and dropped later. Serum levels of creatinine and urea at 24 and 48 h significantly correlated with the Total Antioxidant Activity and lipid peroxidation, respectively. Oxidative stress is shown to be involved in CIN development in the rabbit, with more pronounced effects to be confined to the cortex and outer stripe of the outer medulla.


Assuntos
Meios de Contraste/toxicidade , Iohexol/análogos & derivados , Nefropatias/induzido quimicamente , Rim/patologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Biomarcadores , Creatinina/sangue , Iohexol/toxicidade , Rim/metabolismo , Nefropatias/patologia , Masculino , Oxirredução , Coelhos , Distribuição Aleatória , Ureia/sangue
15.
Toxicol Lett ; 259: 21-27, 2016 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-27346656

RESUMO

Among the various side effects of supra-physiological dose of anabolic androgenic steroids that are described, renal toxicity remains the least evaluated. The present study provides evidence that long-term administration of nandrolone decanoate could lead to alterations of renal function and structure in the experimental rabbit model. A pronounced increase in serum urea, creatinine, SGOT and SGPT is observed in the treated animals, with intramuscular administration being more detrimental. Histopathological evaluation of kidneys indicated hyperaemia, fibrosis and focal inflammation. Furthermore, the significantly increased telomerase activity found in the kidneys of the intramuscularly treated animals could possibly represent a counteracting survival mechanism. Oxidative stress markers that were influenced the most were TBARS, indicating lipid peroxidation, and GSH. An interesting finding in our study though, was that while intramuscular administration showed the highest biochemical derangement, oxidative stress markers provided mixed results between intramuscularly and subcutaneously treated rabbits. In conclusion, nephrotoxicity of nandrolone decanoate remains a multi-factorial, partly irreversible effect that involves augmented tissue oxidative status.


Assuntos
Anabolizantes/toxicidade , Nefropatias/induzido quimicamente , Nandrolona/análogos & derivados , Anabolizantes/administração & dosagem , Animais , Biomarcadores , Esquema de Medicação , Masculino , Nandrolona/administração & dosagem , Nandrolona/toxicidade , Decanoato de Nandrolona , Estresse Oxidativo/efeitos dos fármacos , Coelhos
17.
Appl Physiol Nutr Metab ; 33(6): 1140-54, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19088772

RESUMO

The aim of this study was to examine the effect of allopurinol, a xanthine oxidase inhibitor, on oxidative stress and physical performance after swimming until exhaustion in rats. Blood and gastrocnemius muscle samples were collected before, immediately after, and 5 h after exercise and the respective timepoints after allopurinol administration. Xanthine oxidase and total antioxidant capacity (TAC) were determined in plasma and muscle, whereas catalase activity and reduced (GSH) and oxidized (GSSG) glutathione were measured in erythrocytes and muscle. Thiobarbituric acid-reactive substances (TBARS) and protein carbonyls (PC) were determined in plasma, erythrocytes, and muscle. As expected, allopurinol inhibited xanthine oxidase activity. Compared with their nonallopurinol-treated counterparts, rats treated with allopurinol showed a 35% decrease in physical performance, as indicated by the shorter swimming time to exhaustion. Exercise alone increased PC and TBARS concentration in plasma, erythrocytes, and gastrocnemius muscle. Similarly, allopurinol alone increased PC and TBARS concentration in erythrocytes and gastrocnemius muscle, decreased TAC in plasma and gastrocnemius muscle, and decreased the GSH:GSSG ratio in erythrocytes. Our data illustrate that, in general, exercise and allopurinol alone increased the levels of most of the oxidative stress markers measured in plasma, erythrocytes, and gastrocnemius muscle. Xanthine oxidase inhibition provoked a marked reduction in physical performance.


Assuntos
Alopurinol/administração & dosagem , Inibidores Enzimáticos/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Resistência Física/fisiologia , Natação/fisiologia , Xantina Oxidase/antagonistas & inibidores , Análise de Variância , Animais , Antioxidantes/metabolismo , Biomarcadores/sangue , Eritrócitos/metabolismo , Masculino , Músculo Esquelético/metabolismo , Carbonilação Proteica/fisiologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Fatores de Tempo
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