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1.
Contact Dermatitis ; 86(5): 398-403, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35133669

RESUMO

BACKGROUND: Although the traditional understanding is that contact sensitization is less frequent in patients with atopic dermatitis (AD), recent studies have shown similar or higher rates of positive patch-test results in AD patients. OBJECTIVES: We sought to characterise the pattern of contact sensitization in patients with and without AD and evaluate the association between AD and contact sensitization. METHOD: This was a single-center, 10-year retrospective review of patients who underwent patch testing between 2007 and 2017. RESULTS: There were 4903 patients (male-to-female ratio = 1:1.4; mean age 40.1 years) included. About half (2499, 51.0%) of all patients developed at least one positive reaction. The top five frequent reactions were to nickel sulfate (45.4%), potassium dichromate (16.0%), p-phenylenediamine (13.4%), Myroxylon pereirae (11.8%), and fragrance mix I (11.2%). The overall prevalence of contact sensitization was not significantly different between patients with or without AD. Patients with AD were less likely to develop contact allergies to budesonide and thiuram mix, and more likely to develop contact allergies to potassium dichromate. CONCLUSIONS: Contact sensitization was detected in 50% of patients who were patch tested. Nickel sulfate was the most frequently sensitizing allergen. The prevalence of contact allergies in atopic patients is comparable to that in non-atopic patients.


Assuntos
Dermatite Alérgica de Contato , Dermatite Atópica , Dermatologia , Adulto , Alérgenos/efeitos adversos , Dermatite Alérgica de Contato/epidemiologia , Dermatite Alérgica de Contato/etiologia , Dermatite Atópica/induzido quimicamente , Dermatite Atópica/epidemiologia , Feminino , Humanos , Masculino , Testes do Emplastro/métodos , Dicromato de Potássio/efeitos adversos , Estudos Retrospectivos
2.
Dermatitis ; 32(6): 381-387, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34807530

RESUMO

BACKGROUND: Contact dermatitis in construction workers (CWs) is frequent due to the widespread exposure to sensitizing substances and irritating agents and the wet and cold working conditions. OBJECTIVE: Our objectives were to evaluate contact dermatitis characteristics among CWs who underwent patch test in northeastern Italy and to identify related allergens. METHODS: Seven hundred ninety-five CWs were studied and their data were compared to 2.099 male white-collar workers. The associations between patch test results and occupations were assessed by multivariate logistic regression analysis. Incidence data were calculated from 1996 to 2016. RESULTS: CWs with confirmed occupational dermatitis presented an increased risk to be sensitized to potassium dichromate [OR 3.1 (95%IC 2.0-4.8)], to thiurams [OR 8 .6 (95%IC 4.0-18.4)], and to epoxy resins [OR 12.7 (95%IC 6.1-26.4)]. Sensitization to chromate decreased significantly after 2004, following EU regulation of chromate content in concrete, while sensitization to epoxy resins and thiurams increased. The overall incidence of occupational contact dermatitis in CWs decreased significantly. CONCLUSION: Our study demonstrated the effectiveness of EU regulations in reducing chromate sensitization in CWs and the overall incidence of occupational contact dermatitis. However, sensitization to other haptens is increasing, though improvement of protective measures is compulsory.


Assuntos
Indústria da Construção , Dermatite Alérgica de Contato/epidemiologia , Dermatite Ocupacional/epidemiologia , Irritantes/efeitos adversos , Adulto , Dermatite Alérgica de Contato/diagnóstico , Dermatite Alérgica de Contato/etiologia , Dermatite Ocupacional/diagnóstico , Dermatite Ocupacional/etiologia , Resinas Epóxi/efeitos adversos , Humanos , Incidência , Itália , Masculino , Pessoa de Meia-Idade , Testes do Emplastro/estatística & dados numéricos , Dicromato de Potássio/efeitos adversos , Tiram/efeitos adversos
3.
Int Immunopharmacol ; 101(Pt B): 107867, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34489184

RESUMO

Adenosine monophosphate-activated protein kinase (AMPK) has a crucial role in neuroprotection. It phosphorylates serine/threonine kinase (Akt) Substrate inhibiting the inflammatory responses induced by the nuclear factor-κB (NF-κB). Exposure to chromium VI dust among workers has been reported and induced brain injury, as the absorption of chromium through the nasal membrane has been found to deliver it directly to the brain. The study aimed to investigate the influence of administration of L-carnitine or/and Co Q10 as theraputic agents against potassium dichromate (PD)-induced brain injury via AMPK/AKT/NF-κß signaling pathway. Brain injury was induced by PD intranasally as a single dose of 2 mg/kg, 24 h latter rats received L-carnitine (100 mg/kg; orally), Co Q10 (50 mg/kg; orally) and L-carnitine (50 mg/kg; orally) + Co Q10 (25 mg/kg; orally) respectively for 3 days. Locomotor activity was assessed before and at the end of the experiment, then, biochemical and histopathological investigations were assessed in brain homogenate. The exposure of rats to PD promoted oxidative stress and inflammation via an increase in MDA and a decrease in GSH brain contents with an increase in brain contents of TNF-α, IL-6, and NF-kß and reduced AMPK and AKT brain contents as compared to the control group. Treatment with L-carnitine + Co Q10 ameliorated cognitive impairment and oxidative stress, decreased the brain contents of inflammatory mediators; TNF-α, IL-6, and NF-κß elevated AMPK and AKT, as compared to each drug. Also, L-carnitine + Co Q10 administration restored morphological changes as degenerated neurons and necrosis. L-carnitine + Co Q10 play important role in AMPK/AKT/NF-κß pathway that responsible for their antioxidant and anti-inflammatory effects against PD-induced brain injury in rats.


Assuntos
Lesões Encefálicas/induzido quimicamente , Lesões Encefálicas/tratamento farmacológico , Carnitina/farmacologia , Dicromato de Potássio/toxicidade , Ubiquinona/análogos & derivados , Animais , Biomarcadores/metabolismo , Masculino , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Distribuição Aleatória , Ratos , Ratos Wistar , Ubiquinona/farmacologia , Vitaminas/farmacologia
4.
Dokl Biochem Biophys ; 499(1): 289-295, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34426928

RESUMO

Occupational and environmental exposure to chromium compounds leads to nephrotoxicity to humans and animals due to the overproduction of ROS. Our study was aimed to demonstrate the shielding effect of hydroethanolic extract of Ipomoea staphylina (HEIS) bark on male Wistar rats challenged with potassium dichromate (K2Cr2O7). Division of animals was done in 4 groups' viz., normal control, K2Cr2O7 control, K2Cr2O7+HEIS (100 mg/kg), and K2Cr2O7+HEIS (200 mg/kg). Except for the normal control group, other groups were challenged with a single dose (subcutaneous) of K2Cr2O7 (15 mg/kg) and then treated with HEIS (100 and 200 mg/kg) for 1 week. It was observed that animals treated with K2Cr2O7 showed a notable increase in serum creatinine, blood urea, and BUN and dwindles in protein level. These changes were significantly reversed after a 1-week treatment with HEIS (100 and 200 mg/kg). Moreover, HEIS (100 and 200 mg/kg) showed a remarkable improvement in the activity of antioxidant enzymes (GPx, CAT, and SOD) and decreased the levels of TNF-α and IL-1ß in the kidney. Furthermore, treatment with HEIS (100 and 200 mg/kg) notably decreased the activity of caspase-3 and improved the level of HO-1 especially in the K2Cr2O7+ HEIS (200 mg/kg) group. Also, the histopathological study of the kidney supported the protective effects of HEIS. Hence, HEIS bark holds a notable protective effect against K2Cr2O7-induced nephrotoxicity in rats.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Ipomoea/química , Rim/efeitos dos fármacos , Extratos Vegetais/farmacologia , Dicromato de Potássio/toxicidade , Animais , Catalase/metabolismo , Rim/citologia , Rim/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar
5.
Int J Mol Sci ; 22(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34360943

RESUMO

Good sorption properties and simple synthesis route make schwertmannite an increasingly popular adsorbent. In this work, the adsorption properties of synthetic schwertmannite towards Cr(VI) were investigated. This study aimed to compare the properties and sorption performance of adsorbents obtained by two methods: Fe3+ hydrolysis (SCHA) and Fe2+ oxidation (SCHB). To characterise the sorbents before and after Cr(VI) adsorption, specific surface area, particle size distribution, density, and zeta potential were determined. Additionally, optical micrographs, SEM, and FTIR analyses were performed. Adsorption experiments were performed in varying process conditions: pH, adsorbent dosage, contact time, and initial concentration. Adsorption isotherms were fitted by Freundlich, Langmuir, and Temkin models. Pseudo-first-order, pseudo-second-order, intraparticle diffusion, and liquid film diffusion models were used to fit the kinetics data. Linear regression was used to estimate the parameters of isotherm and kinetic models. The maximum adsorption capacity resulting from the fitted Langmuir isotherm is 42.97 and 17.54 mg·g-1 for SCHA and SCHB. Results show that the adsorption kinetics follows the pseudo-second-order kinetic model. Both iron-based adsorbents are suitable for removing Cr(VI) ions from aqueous solutions. Characterisation of the adsorbents after adsorption suggests that Cr(VI) adsorption can be mainly attributed to ion exchange with SO42- groups.


Assuntos
Compostos Férricos/química , Compostos de Ferro/química , Dicromato de Potássio/química , Adsorção , Hidrólise , Oxirredução
6.
Biomed Res Int ; 2021: 3565360, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34222468

RESUMO

Melatonin (ML) is a potent antioxidant that reduces oxidative stress. This study was designed to examine the protective effect of melatonin on potassium dichromate- (PDC-) induced male reproductive toxicity. Forty rats were divided into five groups: the control group, rats administered PDC orally (10 mg/kg body weight) for eight weeks, rats administered ML intraperitoneally at doses of either 2.5 or 5 mg/kg followed by the administration of PDC, and rats administered 5 mg/kg ML only. The treatment of rats with PDC led to a decrease in the levels of plasma sex hormones, glutathione, superoxide dismutase, catalase, carnitine, sperm count, and motility. Testicular malondialdehyde levels, nitric oxide concentrations, and abnormalities increased significantly in the PDC group. Melatonin administration to the PDC-treated rats reduced the increase of malondialdehyde and restored the activity of antioxidant enzymes (superoxide dismutase and catalase), glutathione, and sex hormone levels. Moreover, ML attenuated PDC-induced increase in levels of tumor necrosis factor-alpha or interleukin-6. ML alleviated histopathological changes and an increase of p53-positive immune reaction due to PDC. Furthermore, ML inhibited PDC-induced decrease in the DNA content of spermatogenic cells. This study proposed that melatonin may be useful in mitigating oxidative stress-induced testicular damage due to potassium dichromate toxicity.


Assuntos
Melatonina/farmacologia , Estresse Oxidativo , Dicromato de Potássio , Testículo/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Peso Corporal , Catalase/metabolismo , Cromatografia Líquida de Alta Pressão , Glutationa/metabolismo , Hormônios Esteroides Gonadais/sangue , Inflamação , Peroxidação de Lipídeos , Masculino , Tamanho do Órgão , Ratos , Ratos Wistar , Contagem de Espermatozoides , Motilidade Espermática/efeitos dos fármacos , Espermatozoides , Superóxido Dismutase/metabolismo
7.
Environ Sci Pollut Res Int ; 28(48): 69426-69435, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34302249

RESUMO

Chromium (Cr) VI is a common environmental contaminant highly toxic to livers. To explore the protective effect of nano-selenium (NANO-Se) on broiler liver damage caused by Cr (VI), this experiment was conducted with chicken hepatocellular carcinoma cell line (LMH) as the research object, using potassium dichromate (PDC) and NANO-Se gel for culturing cells. The results indicated that: (1) in the PDC-exposure group, LMH cells being treated with 20 µmol/L PDC for 24 h, IC50 (median inhibition concentration) = 23.427 could significantly reduce cell activity (p < 0.01) which decreased over time. PDC markedly increased the concentration of triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C) in LMH cells (p < 0.01), which increased over time. In addition, PDC could substantially augment the transcription and protein levels of acetyl-CoA carboxylases alpha (ACACA) and fatty acid synthase (FASN) in LMH cells (p < 0.01). (2) Compared with the PDC-exposure group, the addition of 8 µmol/L NANO-Se after 12 h of PDC treatment could significantly increase the cell viability (p < 0.01) but decreased over time; the levels of TG and LDL-C in LMH cells declined markedly (p < 0.01). In addition, the transcription and protein levels of ACACA and FASN in LMH cells were significantly reduced (p < 0.01). (3) The LMH cells were cultured in advance with 8 µmol/L NANO-Se for 12 h and then with PDC for 24 h. The obtained results were similar to the above. There were no obvious differences in TG and LDL-C levels (p > 0.05). However, significant differences were found in the activity of LMH cells and the expression of genes related to lipid metabolism (p < 0.05).All these results suggest that the exposure to PDC promotes the increase of lipid synthesis in LMH cells and causes disorders in the lipid metabolism. Moreover, NANO-Se can partially attenuate the damage caused by PDC through down-regulating of the lipid metabolism-related genes (ACACA and FASN) in LMH cells.


Assuntos
Transtornos do Metabolismo dos Lipídeos , Selênio , Animais , Galinhas , Ácido Graxo Sintases/metabolismo , Metabolismo dos Lipídeos , Transtornos do Metabolismo dos Lipídeos/metabolismo , Fígado/metabolismo , Dicromato de Potássio , Selênio/metabolismo , Selênio/farmacologia
8.
Environ Toxicol ; 36(11): 2146-2160, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34272807

RESUMO

Environmental and occupational exposure to chromium compounds has become potential aetiologic agent for kidney disease with excessive generation of free radicals, apoptosis, and inflammatory. These pathophysiologic mechanisms of potassium dichromate (K2 Cr2 O7 ) have been well correlated with nephrotoxicity and cardiotoxicity. The cardioprotective and nephroprotective effects of Luteolin, a known potent antioxidant were evaluated in this study with 40 healthy rats in four experimental groups: Group A (normal saline), Groups B (30 mg/kg K2 Cr2 O7 ), Group C (Luteolin 100 mg/kg and K2 Cr2 O7 30 mg/kg), and Group D (Luteolin 200 mg/kg and K2 Cr2 O7 30 mg/kg), respectively. Markers of antioxidant defense system, oxidative stress, blood pressure and micronucleated polychromatic erythrocytes (MnPEs), immunohistochemistry of Kidney, injury molecule (Kim-1), nuclear factor erythroid 2-related factor 2 (Nrf2), and cardiac troponin I were determined. Administration of K2 Cr2 O7 increased blood pressure parameters in systolic, diastolic and mean arterial blood pressures, markers of oxidative stress, and frequency of micronucleated polychromatic erythrocytes, together with reduction in serum nitric oxide level. Renal Kim-1 and cardiac troponin I expressions were higher, but lower expressions of renal and cardiac Nrf2 were recorded with immunohistochemical analysis. Pre-treatment with Luteolin restored blood pressure parameters, with concomitant reduction in oxidative stress indicators, augmented antioxidant mechanisms and serum Nitric oxide level, lowered the expressions of Kim-1, cardiac troponin I and up-regulated of both cardiac and renal Nrf2, reduced the frequency of micronucleated polychromatic erythrocytes. Taken together, this study therefore demonstrates the cardioprotective, nephro protective and antigenotoxic effects of Luteolin through antioxidantive and radical scavenging mechanisms.


Assuntos
Luteolina , Fator 2 Relacionado a NF-E2 , Animais , Antioxidantes/metabolismo , Cardiotoxicidade/metabolismo , Rim/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Dicromato de Potássio/toxicidade , Ratos
9.
J Trace Elem Med Biol ; 67: 126791, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34022565

RESUMO

BACKGROUND: Chromium hexavalent (CrVI) is known as a toxic contaminant that induced oxidative stress and nephrotoxicity in humans and animals. Rosmarinus officinalis is a perennial herb rich in biologically active constituents that have powerful antioxidant properties. So, the current work evaluated the effectiveness of Rosmarinus officinalis essential oil (REO) against alterations induced by potassium dichromate in the kidney of male rats. METHODS: GC-MS analysis, in vitro total phenol contents, and DPPH scavenging activity of REO were estimated. Thirty-five Wistar male rats were categorized into 5 groups. The first group was the control, the second one was orally administered rosemary essential oil (REO; 0.5 mL/kg BW), the third group was injected intraperitoneally with hexavalent chromium (CrVI; 2 mg/kg BW) for 14 days, the fourth group used as the protective group (REO was administrated 30 min before i.p. injection of CrVI) and the fifth group applied as the therapeutic group (rats injected with CrVI 30 min followed by oral administration of REO), respectively. RESULTS: Twenty-nine components were detected with high total phenolic contents and high DPPH scavenging activity. Results revealed that CrVI- intoxicated rats showed a valuable increase in oxidative stress profile (TBARS and H2O2) and a notable decline in glutathione (GSH), total protein content, and enzymatic antioxidants (SOD, CAT, GPx, and GST). Furthermore, serum kidney functions biomarkers (urea, creatinine, and uric acid) were increased significantly. Also, the administration of CrVI showed histological and immunohistochemical (PCNA-ir) changes in rat kidney tissue. Otherwise, administration of REO pre or post-treatment with CrVI significantly restored most of the biochemical parameters in addition to improvement in kidney tissue architecture. Moreover, individual intake with REO exhibited an amendment in oxidative stress markers. CONCLUSION: Conclusively, REO had a potential antioxidant capacity in ameliorating K2Cr2O7-induced nephrotoxicity, especially in the protection group.


Assuntos
Óleos Voláteis , Dicromato de Potássio/toxicidade , Rosmarinus , Animais , Antioxidantes/metabolismo , Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Rim/metabolismo , Peroxidação de Lipídeos , Masculino , Óleos Voláteis/metabolismo , Óleos Voláteis/farmacologia , Estresse Oxidativo , Fenóis/metabolismo , Ratos , Ratos Wistar , Rosmarinus/metabolismo
10.
Microsc Res Tech ; 84(10): 2434-2450, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33908126

RESUMO

The current study has been designed to assess the role of Persea americana (P. americana) pulp extract on potassium dichromate-induced hepatotoxicity in rats. P. americana pulp extract administration improved the hepatic vascular congestion, blood extravasation, inflammatory cellular infiltration, Kupffer cell hyperplasia, and nuclear changes. It also significantly ameliorated hepatic interstitial and peri-portal fibrosis and caused retrieval of the PAS-positive reaction in the liver parenchyma and around the central vein with restoration of the glycogen granules. P. americana also significantly attenuated the immunohistochemical expression of NF-kß p65 and its downstream inflammatory cytokines IL6 and TNFα in the liver parenchyma. The antioxidant effect of P. americana was evidenced by significant modulation of the three major components of the thioredoxin (Trx) antioxidant system, the Trx, the thioredoxin reductase (TrxR), and the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase along with significant increase in the level of superoxide dismutase and glutathione, and decrease in the lipid peroxidation product malondialdehyde. P. americana pulp extract also caused significant elevation of hepatic protein phosphatase 5 with subsequent down-regulation of Apoptosis signal-regulating kinase1 (ASK1) and its downstream signaling targets MAPK kinase 4 (MKK4), p38 mitogen-activated protein kinases (p38-MAPKs), the c-JUN N-terminal kinase (JNK), and the extracellular signal-regulated kinase 1/2 (ERK 1/2). Also, In conclusion, P. americana pulp extract has anti-oxidative and anti-inflammatory effects against potassium dichromate-induced hepatotoxicity.


Assuntos
Persea , Animais , Antioxidantes , Peroxidação de Lipídeos , Extratos Vegetais/farmacologia , Dicromato de Potássio , Ratos
11.
Environ Sci Pollut Res Int ; 28(33): 45317-45334, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33860426

RESUMO

The increasing use and disposal of plastics has become a persistent problem in the marine environment, calling for studies that refer to realistic scenarios to understand their effects on biota. Particularly, the understanding about the effects of co-exposure with nanoplastic particles and metals on aquatic organisms is still limited. The present work aimed to investigate the acute toxicity of amino-functionalized polystyrene nanoparticles (PS-NH2; 50 nm) as proxy for nanoplastics on brine shrimp Artemia franciscana larvae under different culture conditions and at different stages of development, as well as the combined effect with two reference toxicants - potassium dichromate (K2Cr2O7) and copper sulfate (CuSO4). Nauplii (instar II or III larval stages) were exposed to different concentrations of PS-NH2 (0.005 to 5 µg mL-1) for up to 48 h, with or without agitation in order to mimic a more realistic environmental scenario. Larval mobility and PS-NH2 accumulation were monitored under microscopy. PS-NH2 alone showed toxicity only at the highest concentration tested (5 µg mL-1) regardless the incubation method used (61.2 + 3.1% and 65.0 + 4.5% with and without agitation, respectively). Moreover, instar III stage was the most sensitive to PS-NH2 exposure (38.2% immobility in 24 h of exposure; 5 µg mL-1). Evidence of PS-NH2 retention in the gastrointestinal tract in a concentration- and time-dependent manner was also obtained. Mixtures of PS-NH2 (0.005 and 5 µg mL-1) with different concentrations of K2Cr2O7 increased the immobilization rate of the larvae after 48 h of exposure, when compared to the K2Cr2O7 alone. Similar results were observed for CuSO4 in the co-exposure conditions at different concentrations. However, exposing nauplii to a mixture of PS-NH2 (0.005 µg mL-1) and CuSO4 decreased immobilization rate, in comparison to the group exposed to CuSO4 alone. The present work highlights the potential risk posed by nanoplastics to zooplanktonic species through their interaction with other toxicants.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Animais , Artemia , Sulfato de Cobre/toxicidade , Larva , Poliestirenos , Dicromato de Potássio/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
12.
Reprod Toxicol ; 101: 63-73, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33675932

RESUMO

We have reported sub-fertility in F1 progeny rats with gestational exposure to hexavalent chromium [Cr(VI)], which had disrupted Sertoli cell (SC) structure and function, and decreased testosterone (T). However, the underlying mechanism for reduced T remains to be understood. We tested the hypothesis "transient prenatal exposure to Cr(VI) affects testicular steroidogenesis by altering hormone receptors and steroidogenic enzyme proteins in Leydig cells (LCs)." Pregnant Wistar rats were given drinking water containing 50, 100, and 200 mg/L potassium dichromate during gestational days 9-14, encompassing fetal differentiation window of the testis from the bipotential gonad. F1 male rats were euthanized on postnatal day 60 (peripubertal rats with adult-type LCs alone). Results showed that prenatal exposure to Cr(VI): (i) increased accumulation of Cr(III) in the testis of F1 rats; (ii) increased serum levels of luteinizing and follicle stimulating hormones (LH and FSH), and 17ß estradiol, and decreased prolactin and T; (iii) decreased steroidogenic acute regulatory protein, cytochrome P450 11A1, cytochrome P450 17A1, 3ß- and 17ß-hydroxysteroid dehydrogenases, cytochrome P450 aromatase and 5α reductase proteins, (iv) decreased specific activities of 3ß and 17ß hydroxysteroid dehydrogenases; (v) decreased receptors of LH, androgen and estrogen in LCs; (vi) decreased 5α reductase and receptor proteins of FSH, androgen, and estrogen in SCs. The current study concludes that prenatal exposure to Cr(VI) disrupts testicular steroidogenesis in F1 progeny by repressing hormone receptors and key proteins of the steroidogenic pathway in LCs and SCs.


Assuntos
Carcinógenos Ambientais/toxicidade , Cromo/toxicidade , Dicromato de Potássio/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Testículo/efeitos dos fármacos , 17-Hidroxiesteroide Desidrogenases/metabolismo , Animais , Colestenona 5 alfa-Redutase/metabolismo , Cromo/sangue , Feminino , Hormônios/sangue , Masculino , Troca Materno-Fetal , Dicromato de Potássio/sangue , Gravidez , Ratos Wistar , Receptores do LH/metabolismo , Receptores da Prolactina/metabolismo , Receptores de Esteroides/metabolismo , Testículo/metabolismo , Testículo/patologia
13.
PLoS One ; 16(2): e0247426, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33606832

RESUMO

Aquatic organisms have been used to investigate the safety of chemicals worldwide. One such assessment is an algal growth inhibition test. Algal growth inhibition tests are commonly performed using a growth chamber with fluorescent lamps as the lighting source, as test guidelines require continuous uniform fluorescent illumination. However, fluorescent lamps contain mercury, which has been identified as hazardous to humans and other organisms. The Minamata Convention (adopted in 2013) requires reduction or prohibition of products containing mercury. On the other hand, light-emitting diodes do not contain mercury and provide a photosynthetically effective wavelength range of 400-700 nm which is an adequate light intensity for algal growth. Light-emitting diodes are thus preferable to fluorescent lamps as a potential light source in algal growth inhibition tests. In this study, we investigated if light-emitting diodes could be substituted for fluorescent lamps in growth inhibition studies with green alga (Pseudokirchneriella subcapitata), diatom (Navicula pelliculosa), and cyanobacteria (Anabaena flos-aquae). Algal growth inhibition tests were performed using five different chemicals known to have different modes of action and are assigned as reference substances in the test guidelines. The results of each algal test showed similar values between light-emitting diodes and fluorescent lamps in terms of conditions for the growth inhibition rate and percent inhibition in yield of each chemical. It was therefore concluded that using light-emitting diodes instead of fluorescent lamps as a lighting source had no effect on the algal growth inhibition test results.


Assuntos
Clorófitas/crescimento & desenvolvimento , Cianobactérias/crescimento & desenvolvimento , Diatomáceas/crescimento & desenvolvimento , Luz/efeitos adversos , Cloreto de Cádmio/farmacologia , Clorofenóis/farmacologia , Fluorescência , Técnicas Microbiológicas , Pressão Osmótica/efeitos dos fármacos , Fosforilação Oxidativa/efeitos dos fármacos , Pentaclorofenol/farmacologia , Fotossíntese/efeitos dos fármacos , Dicromato de Potássio/farmacologia , Cloreto de Sódio/farmacologia
14.
Environ Sci Pollut Res Int ; 28(18): 22563-22576, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33423197

RESUMO

Hexavalent chromium (CrVI) is an environmental pollutant and an endocrine-disrupting metal. Se and Zn are essential trace elements, known to play a crucial role in thyroid homeostasis. However, there is a lack of data reporting thyrotoxicity during gestation. In this study, we investigated the protective effects of selenium and zinc against potassium dichromate-induced thyrotoxicity in pregnant Wistar rats. Thirty pregnant Wistar rats were divided into control and four treated groups receiving subcutaneously (s.c) on the 3rd day of pregnancy, K2Cr2O7 (10 mg/kg, s.c) alone, or in association with Se (0.3 mg/kg, s.c), ZnCl2 (20 mg/kg, s.c), or both of them simultaneously. The hormonal profile, oxidative stress biomarkers, DNA damage, and histological modifications were evaluated. Our main findings showed that K2Cr2O7 promoted hypothyroidism, oxidative stress, genotoxicity, and histological alterations in the thyroid gland. The co-treatment with Se or ZnCl2 has mitigated K2Cr2O7-induced thyrotoxicity in pregnant Wistar rats by exhibiting antioxidant and genoprotective effects. However, the combined co-treatment of both of them was less thyroprotective, and therefore, further investigations on the synergetic interaction of Se and Zn against CrVI toxicity using different doses and exposure routes are required.


Assuntos
Dicromato de Potássio , Selênio , Animais , Dano ao DNA , Feminino , Estresse Oxidativo , Dicromato de Potássio/toxicidade , Gravidez , Ratos , Ratos Wistar , Selênio/farmacologia , Glândula Tireoide , Zinco
15.
Drug Chem Toxicol ; 44(3): 277-285, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-30849244

RESUMO

Heavy metal pollution is rapidly increasing in the environment. It has been shown that exposure to vanadium and chromium is able to alter the immune response. Nevertheless, the mechanisms by which these metal pollutants mediate their immunomodulatory effects are not completely understood. Herein, we examined the effect of ammonium metavanadate and potassium dichromate on the development of an inflammatory response caused by subcutaneous injection of turpentine oil. We demonstrated that pretreatment of rats with ammonium metavanadate and potassium dichromate for two weeks prior to initiation of the inflammatory response resulted in a wider zone of necrosis surrounding the site of inflammation. The acute inflammatory process in the combined model was characterized by elevated serum levels of IL-10 and decreased serum levels of IL-6 as compared to rats not treated with ammonium metavanadate and potassium dichromate. Ammonium metavanadate and potassium dichromate administration induced a decrease in the proportion of splenic His48HighCD11b/c+ myeloid cells accompanied by a reduced infiltration of the wound with neutrophils. Further analysis showed decreased proportions of CD3+CD4+IFNγ+ and CD3+CD4+IL-4+ T cells in the rats with combined model as compared to inflamed rats not treated with ammonium metavanadate and potassium dichromate. The data suggest that consumption of vanadium and chromium compounds disrupts the inflammatory response through an altered balance of pro- and anti-inflammatory cytokines and inhibition of effector T cell activation and neutrophil expansion.


Assuntos
Inflamação/prevenção & controle , Dicromato de Potássio/farmacologia , Terebintina/toxicidade , Vanadatos/farmacologia , Administração Oral , Animais , Inflamação/induzido quimicamente , Interleucina-10/sangue , Interleucina-6/sangue , Masculino , Dicromato de Potássio/administração & dosagem , Ratos , Vanadatos/administração & dosagem
16.
Contact Dermatitis ; 84(3): 153-158, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32996589

RESUMO

BACKGROUND: In Sweden, cobalt chloride 0.5% has been included in the baseline series since the mid-1980s. A recent study from Stockholm showed that cobalt chloride 1% petrolatum (pet.) was more suitable than 0.5%. Cobalt chloride at 1.0% has been patch tested for decades in many European countries and around the world. OBJECTIVES: To study the suitability of patch testing to cobalt 1.0% vs 0.5% and to analyze the co-occurrence of allergy to cobalt, chromium, and nickel. RESULTS: Contact allergy to cobalt was shown in 90 patients (6.6%). Eighty (5.9%) patients tested positive to cobalt 1.0%. Thirty-seven of the 90 patients (41.1%) with cobalt allergy were missed by cobalt 0.5% and 10 (0.7%) were missed by cobalt 1.0% (P < .001). No case of patch test sensitization was reported. Allergy to chromium was seen in 2.6% and allergy to nickel in 13.3%. Solitary allergy to cobalt without nickel allergy was shown in 61.1% of cobalt-positive individuals. Female patients had larger proportions of positive reactions to cobalt (P = .036) and nickel (P < .001) than males. CONCLUSION: The results speak in favor of replacing cobalt chloride 0.5% with cobalt chloride 1.0% pet. in the Swedish baseline series, which will be done 2021.


Assuntos
Alérgenos/administração & dosagem , Cobalto/administração & dosagem , Dermatite Alérgica de Contato/diagnóstico , Níquel/administração & dosagem , Testes do Emplastro/métodos , Dicromato de Potássio/administração & dosagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Suécia , Adulto Jovem
17.
Chemosphere ; 264(Pt 2): 128547, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33049514

RESUMO

Hexavalent chromium (Cr(VI)), the most toxic valence state of chromium, is widely present in industrial effluents and wastes. Although previous study has reported that Cr(VI) can cause cytomembrane structure impairment by aggravating lipid peroxidation in the heart, the detailed mechanism of Cr(VI)-induced heart dysfunction is still unclear. Sesn2, a novel antioxidant and stress-inducible molecule, is evidenced to protect against various cardiometabolic diseases such as atherosclerosis and cardiomyopathy. To define the potential mechanism of heart dysfunction induced by chronic Cr(VI) exposure, Wistar rats were intraperitoneal injected with potassium dichromate (K2Cr2O7) for 35 d in the present study. The data showed that chronic K2Cr2O7 exposure caused dose-dependently hematological variations, oxidative stress, dysfunction, and disorganized structure of heart, cardiomyocyte apoptosis, ATP depletion, and mitochondria impairment in rats. In addition, the expressions of Drp1 and Bax were increased by K2Cr2O7. However, the suppression of Mfn2, PGC-1α, Sesn2, nuclear Nrf2, HO-1, and NQO1 protein levels was observed in K2Cr2O7-treated rat hearts. In conclusion, these results demonstrate that chronic K2Cr2O7 exposure dose-dependently causes heart dysfunction, and the molecular mechanism of this event is associated with the loss of Sesn2 mediated mitochondrial function and energy supply impairment.


Assuntos
Cardiomiopatias , Cromo , Animais , Cromo/toxicidade , Mitocôndrias , Estresse Oxidativo , Dicromato de Potássio , Ratos , Ratos Wistar
18.
Chemosphere ; 266: 129005, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33279236

RESUMO

Hexavalent chromium (Cr(VI)) is an environmental pollutant with vast mutagenic and carcinogenic potential. Various past and recent studies confirm the deleterious effects of Cr(VI) in different models, from invertebrates to mammalians. However, there is a lack of studies that comprehensively assess and correlate Cr(VI) accumulation patterns and the resulting physiological responses. Here we used an attractive toxicological model, male Japanese quail (Coturnix japonica), as an alternative probing system to evaluate Cr(VI) accumulation in the vital organs, including the brain, heart, kidneys, liver, and testes after 20 days of exposure to 1.2 µg/mL and 2.4 µg/mL potassium dichromate-K2Cr2O7 ingested in the form of drinking water. The observed effects were correlated with the shift in immune system readiness, hematological indices, serum biochemistry and enzyme activity. Regardless of the exposure dose, the Cr(VI) distribution and accumulation pattern in terms of relative Cr(VI) concentration in tissues was: testes > kidneys > liver > heart > brain. Moreover, Cr(VI) triggered the development of microcytic and hypochromic anemia and reduced the immune system's readiness to cope with challenges. Besides, serum biochemistry presented significant shifts, including reduction of serum electrolytes and proteins and an increase in creatine kinase (CK) and lactate dehydrogenase (LDH) activity. Our study provides novel toxicological data that can be translated to higher animal models to help in the extrapolation of Cr(VI) toxicity in humans.


Assuntos
Coturnix , Codorniz , Animais , Cromo/toxicidade , Humanos , Masculino , Dicromato de Potássio
19.
Food Chem Toxicol ; 145: 111774, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32980475

RESUMO

Curcumin has protective effects in several acute kidney injury models, including that induced by potassium dichromate (K2Cr2O7). The protective effect of curcumin in this experimental model has been associated to the preservation of mitochondrial bioenergetics. This study is aimed at evaluating whether or not curcumin's protective effect in mitochondrial bioenergetics is related to the modulation of mitochondrial dynamics and biogenesis. Wistar rats were treated with a single subcutaneous dose of K2Cr2O7 (12.5 mg/kg) or received curcumin (400 mg/kg/day) by oral gavage 10 days before and one day after the K2Cr2O7 injection. K2Cr2O7 induced kidney dysfunction and increased mitochondrial hydrogen peroxide production, while decreasing the respiration directly attributable to oxidative phosphorylation and mitochondrial membrane potential. In mitochondria, K2Cr2O7 increased fission and reduced fusion. Structural analysis of mitochondria in the proximal tubular cells corroborated their fragmentation and loss of crests' integrity. Regarding mitochondrial biogenesis, K2Cr2O7 decreased peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) levels. Conversely, curcumin treatment mitigated the aforementioned alterations and increased the expression of the mitochondrial transcription factor A (TFAM). Taken together, our results suggest that curcumin can protect against renal injury by modulating mitochondrial homeostasis, mitigating alterations in bioenergetics and dynamics, possibly by stimulating mitochondrial biogenesis.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Curcumina/administração & dosagem , Mitocôndrias/efeitos dos fármacos , Dicromato de Potássio/efeitos adversos , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/genética , Injúria Renal Aguda/metabolismo , Animais , Homeostase/efeitos dos fármacos , Humanos , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Mitocôndrias/genética , Mitocôndrias/metabolismo , Dinâmica Mitocondrial/efeitos dos fármacos , Biogênese de Organelas , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Ratos , Ratos Wistar , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
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