RESUMO
Metals exert detrimental effects on various systems within the body, including the nervous system. Nevertheless, the dose-response relationship concerning the administration of low doses of metal mixtures remains inadequately explored. The assessment of neurotoxic effects of lead, cadmium, mercury, and arsenic mixture (MIX) administered at low dose ranges, was conducted using an in vivo approach. A subacute study was conducted on a rat model consisting of a control and five treatment groups subjected to oral exposure with gradually increasing doses (from MIX 1 to MIX 5). The results indicated that behavioural patterns in an already developed nervous system displayed a reduced susceptibility to the metal mixture exposure with tendency of higher doses to alter short term memory. However, the vulnerability of the mature brain to even minimal amounts of the investigated metal mixture was evident, particularly in the context of oxidative stress. Moreover, the study highlights superoxide dismutase's sensitivity as an early-stage neurotoxicity marker, as indicated by dose-dependent induction of oxidative stress in the brain revealed through Benchmark analysis. The narrowest Benchmark Dose Interval (BMDI) for superoxide dismutase (SOD) activity (1e-06 - 3.18e-05 mg As/kg b.w./day) indicates that arsenic may dictate the alterations in SOD activity when co-exposed with the other examined metals. The predicted Benchmark doses for oxidative stress parameters were very low, supporting "no-threshold" concept. Histopathological alterations were most severe in the groups treated with higher doses of metal mixture. Similarly, the brain acetylcholinesterase (AChE) activity demonstrated a dose-dependent decrease significant in higher doses, while BMDI suggested Cd as the main contributor in the examined metal mixture. These findings imply varying susceptibility of neurotoxic endpoints to different doses of environmentally relevant metal mixtures, advocating for risk assessment and regulatory measures to address metal pollution and enhance remediation strategies.
Assuntos
Relação Dose-Resposta a Droga , Animais , Ratos , Masculino , Poluentes Ambientais/toxicidade , Encéfalo/efeitos dos fármacos , Metais Pesados/toxicidade , Síndromes Neurotóxicas/etiologia , Ratos Wistar , Arsênio/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismoRESUMO
The present study investigated the effects of PCBs on the rat kidneys with attention given to the determination critical effect dose (CED) using the Benchmark dose (BMD) approach. Male albino Wistar rats (7 animals per group) were given by oral gavage Aroclor 1254 dissolved in corn oil at doses of 0.0, 0.5, 1, 2, 4, 8, or 16 mg/kg b.w./day for 28 days. The PCB nephrotoxicity was manifested by a dose-dependent changes in serum urea levels. The study has also revealed PCB-induced oxidative stress induction in kidneys. The observed nephrotoxic effects can be partly explained by oxidative damage of lipids and proteins in the kidneys due to observed reduced CuZnSOD activity and disturbances in antioxidant protection. Ðll the renal oxidative stress parameters showed dependence on PCB oral doses as well as internal, measure kidney PCB levels. Calculated BMDL values were lower than estimated no observed adverse effect levels (NOAEL) based on the study, suggesting the importance of BMD approach use in future risk assessment.
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Bifenilos Policlorados , Ratos , Animais , Masculino , Bifenilos Policlorados/toxicidade , Ratos Sprague-Dawley , Ratos Wistar , Rim , Modelos AnimaisRESUMO
The purpose of this study was to examine the impact of low doses of lead (Pb) on levels of thyroid hormones (T3, T4, FT3, and FT4) and thyroid-related antibodies (anti-Tg and anti-TPO) in the rat model, as well as genes that are related to Pb and thyroid function, relationships between genes, biological processes, molecular processes, and pathways using an in silico approach. Male rats were randomized into seven groups (n = 42), one control group and six groups that received a range of Pb doses: 0.1, 0.5, 1, 3, 7, and 15 mg Pb/kg body weight (b.w.). Dose-response modelling was performed by PROAST software using model averaging method. The Comparative Toxicogenomics Database, GeneMANIA server, and ToppGene Suite portal were used as the main bioinformatic tools in this analysis. The results of our study have shown that low Pb doses induced elevation of thyroid hormones (T4, FT4, and TSH) in rats after subacute exposure, while had no impact on T3, FT3, anti-TPO, and anti-Tg, indicating hyperthyroidism. Dose-dependent effects were increases in T4 and FT4, with the lowest benchmark dose derived for FT4 levels. In silico toxicogenomic data analysis showed that the main molecular pathways/process related to Pb-induced hyperthyroidism are connected with 14 genes involved in antioxidant defense and Se-dependent processes. The results presented here may be useful in further investigation of the health impacts of low-level Pb exposure on thyroid function and endocrine disruption effects.
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Toxic metals (cadmium (Cd), lead (Pb), mercury (Hg) and arsenic (As)) and plastificators (bis (2 - ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP)) and bisphenol A (BPA)) have been suggested to aid in colorectal carcinoma (CRC) advancement. Sulforaphane (SFN), isothiocyanate from cruciferous vegetables, diminishes chemical carcinogenesis susceptibility, but has been shown to act as a friend or a foe depending on various factors. By conducting the mechanistic toxicogenomic data mining approach, this research aimed to determine if SFN can alleviate toxic-metal and/or phthalate/BPA mixture-induced CRC at the gene level. Comparative Toxicogenomics Database, ToppGene Suite portal, Cytoscape software, InteractiVenn and Gene Expression Omnibus (GEO) database (GEO2R tool) was used. Among the mutual genes for all the investigated substances, SFN had a protective impact only through PTGS2. Other proposed protective SFN-targets included ABCA1, ALDH2, BMP2, DPYD, MYC, SLCO2A1, and SOD2, only in the case of phthalates/BPA exposure. The only additional gene relevant for SFN protection against the toxic metal mixture-induced CRC was ABCB1. Additionally, the majority of the top 15 molecular pathways extracted for SFN impact on phthalate and BPA mixture-linked CRC development were directly linked with cancer development, which was not the case with the toxic metal mixture. The current research has indicated that SFN is a more effective chemoprotective agent against CRC induced by phthalates/BPA mixture than by toxic-metal mixture. It has also presented the value of computational methods as a simple tool for directing further research, selecting appropriate biomarkers and exploring the mechanisms of toxicity.
Assuntos
Neoplasias Colorretais , Mercúrio , Transportadores de Ânions Orgânicos , Ácidos Ftálicos , Humanos , Saúde Pública , Toxicogenética , Ácidos Ftálicos/toxicidade , Isotiocianatos/toxicidade , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/genética , Compostos Benzidrílicos/toxicidade , Aldeído-Desidrogenase MitocondrialRESUMO
Toxicological research is mostly limited to considering the effects of a single substance, even though the real exposure of people is reflected in their daily exposure to many different chemical substances in low-doses. This in silico toxicogenomic study aims to provide evidence for the selected environmental (organo)metals (lead, cadmium, methyl mercury) + polychlorinated biphenyls mixture involvement in the possible alteration of thyroid, and male reproductive system function, and furthermore to predict the possible toxic mechanisms of the environmental cocktail. The Comparative Toxicogenomic Database, GeneMANIA online software, and ToppGene Suite portal were used as the main tools for toxicogenomic data mining and gene ontology analysis. The results show that 35 annotated common genes between selected chemicals and endocrine system diseases can interact on the co-expression level. Our study highlighted the disruption of the cytokines, the cell's response to oxidative stress, and the influence of the transcription factors as the potential core of toxicological mechanisms of the discussed mixture's effects. The connected toxicological effects of the tested mixture were abnormal sperm cells, a disrupted level of testosterone, and thyroid hormones. The core mechanisms of these effects were inflammation, oxidative stress, disruption of androgen receptor signaling, and the alteration of the FOXO3-Keap-1/NRF2-HMOX1-NQO1 pathway signaling most likely controlled by the co-expression of overlapped genes among used chemicals. This in silico research can be used as a potential core for the determination of biomarkers that can be monitored in future further in vitro and in vivo experiments.
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Bifenilos Policlorados , Humanos , Masculino , Bifenilos Policlorados/toxicidade , Glândula Tireoide , Toxicogenética , Sêmen , Hormônios TireóideosRESUMO
The major goal of this study was to estimate the correlations and dose-response pattern between the measured blood toxic metals (cadmium (Cd), mercury (Hg), chromium (Cr), nickel (Ni))/metalloid (arsenic (As)) and serum insulin level by conducting Benchmark dose (BMD) analysis of human data. The study involved 435 non-occupationally exposed individuals (217 men and 218 women). The samples were collected at health care institutions in Belgrade, Serbia, from January 2019 to May 2021. Blood sample preparation was conducted by microwave digestion. Cd was measured by graphite furnace atomic absorption spectrophotometry (GF-AAS), while inductively coupled plasma-mass spectrometry (ICP-MS) was used to measure Hg, Ni, Cr and As. BMD analysis of insulin levels represented as quantal data was done using the PROAST software version 70.1 (model averaging methodology, BMD response: 10%). In the male population, there was no correlation between toxic metal/metalloid concentrations and insulin level. However, in the female population/whole population, a high positive correlation for As and Hg, and a strong negative correlation for Ni and measured serum insulin level was established. BMD modelling revealed quantitative associations between blood toxic metal/metalloid concentrations and serum insulin levels. All the estimated BMD intervals were wide except the one for As, reflecting a high degree of confidence in the estimations and possible role of As as a metabolic disruptor. These results indicate that, in the case of As blood concentrations, even values higher than BMD (BMDL): 3.27 (1.26) (male population), 2.79 (0.771) (female population), or 1.18 (2.96) µg/L (whole population) might contribute to a 10% higher risk of insulin level alterations, meaning 10% higher risk of blood insulin increasing from within reference range to above reference range. The obtained results contribute to the current body of knowledge on the use of BMD modelling for analysing human data.
Assuntos
Arsênio , Grafite , Insulinas , Mercúrio , Arsênio/toxicidade , Benchmarking , Cádmio , Cromo/análise , Feminino , Grafite/química , Humanos , Masculino , NíquelRESUMO
This study aimed to investigate the potential hepatotoxicity, nephrotoxic, and hematotoxic effects of simultaneous occupational low-level exposure of shoe workers to a mixture of organic solvents. The study included 16 male and 55 female workers and non-exposed subjects (n = 60) in the control group. Along with a standard sets of hematological, liver enzymes (aspartate aminotransferase (AST), alanine aminotransferase (ALT) and gamma-glutamyl transpeptidase (GGT), bilirubin total, bilirubin direct, blood glucose, urea, and creatinine were analyzed in all participants. Indoor air quality was monitored using a Gasmet Dx - 4000 multi-component analyzer. Despite the concentration levels of individual chemicals in shoe production units were below the permissible limits, the equivalent exposure (Em) values calculated based on the American Conference of Governmental Industrial Hygienists (ACGIH) and National Institute of Occupational Safety and Health (NIOSH) occupational exposure limits were higher than 1. Statistically significant increase of biochemical parameters (aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), total bilirubin, and direct bilirubin) was obtained in exposed workers of both genders compared with controls (p < 0.001). Calculated liver damage risk scores were significantly higher in both females and males compared with controls (p < 0.001). The multivariate logistic regression analysis showed that direct bilirubin was the most important predictor of organic solvent mixture exposure in the studied group of workers. These results suggest that combined exposure to organic solvents even at low concentrations may lead to hepatotoxicity.
Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Exposição Ocupacional , Alanina Transaminase , Aspartato Aminotransferases , Bilirrubina/análise , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Feminino , Humanos , Masculino , Exposição Ocupacional/efeitos adversos , Sapatos , Solventes/toxicidade , gama-GlutamiltransferaseRESUMO
This in silico toxicogenomic analysis aims to: (i) testify the hypothesis about the influence of the environmentally relevant toxic metals (lead, methylmercury (organic form of mercury), cadmium and arsenic) on molecular mechanisms involved in amyotrophic lateral sclerosis (ALS), Parkinson's Disease (PD) and Alzheimer's disease (AD) development; and (ii) demonstrate the capability of in silico toxicogenomic data-mining for distinguishing the probable mechanisms of mixture-induced toxic effects. The Comparative Toxicogenomics Database (CTD; http://ctd. mdibl.org) and Cytoscape software were used as the main data-mining tools in this analysis. The results have shown that there were 7, 13 and 14 common genes for all the metals present in the mixture for each of the selected neurodegenerative disease (ND), respectively: ALS, PD and AD. Physical interactions (68.18%) were the most prominent interactions between the genes extracted for ALS, co-expression (60.85%) for PD and interactions predicted by the server (44.30%) for AD. SOD2 gene was noted as the mutual gene for all the selected ND. Oxidative stress, folate metabolism, vitamin B12, AGE-RAGE, apoptosis were noted as the key disrupted molecular pathways that contribute to the neurodegenerative disease's development. Gene ontology analysis revealed biological processes affected by the investigated mixture (glutathione metabolic process was listed as the most important for ALS, cellular response to toxic substance for PD, and neuron death for AD). Our results emphasize the role of oxidative stress, particularly SOD2, in neurodegeneration triggered by environmental toxic metal mixture and give a new insight into common molecular mechanisms involved in ALS, PD and AD pathology.
Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Simulação por Computador , Mineração de Dados , Humanos , Doenças Neurodegenerativas/induzido quimicamente , Doenças Neurodegenerativas/genética , ToxicogenéticaRESUMO
Breast cancer is at the forefront of female malignancy and the leading cause of cancer death among women. Gender, age, hormone therapy, smoking, exposure to endocrine disruptors and family history are significant breast cancer risk factors according to epidemiological data. Considering metalloestrogenic Cd property and a plethora of research work on hormone involvement in breast cancer the study aimed to determine Cd concentration in three compartments of breast cancer patients in relation to their blood hormone status. Further, as oxidative stress is a critical mechanism of Cd toxicity, the objective of this study was to determine potential changes in oxidative status homeostasis. The study enrolled 55 patients with breast cancer diagnosis and 41 healthy women with benign breast changes. Concentration of Cd was determined using graphite furnace atomic absorption spectrometry. Cadmium concentration in tumor tissue was significantly higher than control and almost four times higher than Cd concentration in the healthy surrounding tissue. Strong positive correlation was observed between Cd concentrations in changed breast tissue and FSH and LH levels, while the correlation was negative with estradiol level. Cancer patients had significantly increased blood total antioxidative status while total oxidative status did not significantly differ between study groups. The study revealed Cd implication in breast cancer onset following a significant odd ratio for Cd levels in changed tissue samples. Moreover, presented data confirmed sex hormone and oxidative status imbalance caused by Cd presence, closely related to cancer development.
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Neoplasias da Mama , Cádmio , Cádmio/toxicidade , Estudos de Casos e Controles , Feminino , Humanos , Estresse Oxidativo , Espectrofotometria AtômicaRESUMO
Exposure to cadmium (Cd) is recognised as one of the risk factors for osteoporosis, although critical exposure levels and exact mechanisms are still unknown. Here, we first confirmed that in male Wistar rats challenged orally with 6 different levels of Cd (0.3-10â¯mg/kg b.w.), over 28 days, there was a direct dose relationship to bone Cd concentration. Moreover, bone mineral content was significantly diminished by â¼15% (pâ¯<â¯0.0001) plateauing already at the lowest exposure level. For the other essential bone elements zinc (Zn) loss was most marked. Having established the sensitive metrics (measures of Cd exposure), we then applied them to 20 randomly selected human femoral head bone samples from 16 independent subjects. Bone Cd concentration was inversely proportional to trabecular bone mineral density and mineral (calcium) content and Zn content of bone, but not the donor's age. Our findings, through direct bone analyses, support the emerging epidemiological view that bone health, adjudged by mineral density, is extremely sensitive to even background levels of environmental Cd. Importantly, however, our data also suggest that Cd may play an even greater role in compromised bone health than prior indirect estimates of exposure could reveal. Environmental Cd may be a substantially determining factor in osteoporosis and large cohort studies with direct bone analyses are now merited.
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Densidade Óssea/efeitos dos fármacos , Cádmio/toxicidade , Exposição Ambiental , Animais , Osso e Ossos , Humanos , Masculino , Minerais , Ratos , Ratos WistarRESUMO
Magnesium (Mg), is not only a modulator of the glutamatergic NMDA receptors' affinity, it also prevents HPA axis hyperactivity, thus possibly being implicated in neurobiological features of mood disorders. Further uncovering of molecular mechanisms underlying magnesium's proposed effects is needed due to the recent shift in research of treatment resistant depression (TRD) towards glutamatergic pathways. Here, we applied Mg via drinking water for 28â¯days (50â¯mg/kg/day), in ACTH-treated rats, an established animal model of depression resistant to tricyclic antidepressants. Using this model in male rats we measured (1) changes in hippocampal neurogenesis and behavioral alterations, (2) adrenal hormones response to acute stress challenge and (3) levels of biometals involved in regulation of monoamines turnover in rat prefrontal cortex. Our results support beneficial behavioral impact of Mg in TRD model together with increased hippocampal neurogenesis and BDNF expression. Furthermore, Mg prevented ACTH-induced disruption in HPA axis function, by normalizing the levels of plasma ACTH, corticosterone and interleukin-6, and by increasing the peripheral release of adrenaline, noradrenaline and serotonin after the acute stress challenge. Finally, the influence on copper/zinc ratio suggested probable magnesium's involvement in monoamine turnover in PFC. Our findings provide further insights into the possible pathways implicated in the behavioral modulation effects of Mg, as well as its central and peripheral effects in ACTH-induced TRD model. Thus, further investigation of molecular signaling related to the glutamatergic transmission and role of Mg, could reveal prospects to novel treatment strategies that could be of particular importance for patients suffering from TRD.
Assuntos
Antidepressivos Tricíclicos/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Depressão , Magnésio/farmacologia , Sistemas Neurossecretores/efeitos dos fármacos , Hormônio Adrenocorticotrópico , Animais , Corticosterona/sangue , Depressão/induzido quimicamente , Depressão/tratamento farmacológico , Depressão/patologia , Modelos Animais de Doenças , Resistência a Medicamentos/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Magnésio/administração & dosagem , Masculino , Neurogênese/efeitos dos fármacos , Sistemas Neurossecretores/fisiologia , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/metabolismo , Ratos , Ratos Wistar , Fatores de Tempo , Falha de TratamentoRESUMO
Blood lead levels (BLLs) have been falling steadily worldwide due to restricted use of lead (Pb) and its compounds. although they remain above preindustrial Pb levels. Elevated BLL can still be found in children living near secondary Pb smelters that represent around 50% of Pb production. There have been no studies on Pb exposure in children living in Serbia ever since the 1980s. The aim of this study was to evaluate the BLLs in children living in two villages in Serbia (Zajaca, the location of a secondary lead smelter, and Paskovac, 5â¯km away), identify the primary determinants of children's BLLs, and investigate the impact of BLLs on children's health symptoms and school achievement. The study was conducted in 2011 on 127 children, aged 1-18 years, whose BLLs were measured using inductively coupled argon plasma mass spectrometry (ICP-MS). The median BLL in children was 12⯵g/dl, with a significantly higher value of 17.5⯵g/dl in Zajaca, compared to 7.6⯵g/dl in Paskovac. Only 1 out of 75 and 12 out of 52 children from Zajaca and Paskovac, respectively, had BLLs below the CDC recommended 5⯵g/dl level. Living near the smelter resulted in 19 times, and having a father who works in the plant 4 times higher odds of elevated BLLs. No significant effects of elevated BLLs health symptoms were seen in this study. BLLs of children living near a battery recycling plant in Serbia, an upper-middle income European country, were in the range and even higher than those of children living in developing countries. For the first time, the contribution of environmental and take-home lead exposure was quantified using mixed-effect modeling, and our results indicate a contribution of 25-40% of the take-home lead exposure to the BLLs of children living in the vicinity of a secondary lead smelter.
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Intoxicação por Chumbo , Chumbo , Adolescente , Criança , Pré-Escolar , Fontes de Energia Elétrica , Exposição Ambiental/efeitos adversos , Humanos , Lactente , Intoxicação por Chumbo/epidemiologia , Reciclagem , SérviaRESUMO
Humans are exposed to a significant number of chemicals that are suspected to produce disturbances in hormone homeostasis. Hence, in recent decades, there has been a growing interest in endocrine disruptive chemicals. One of the alleged thyroid disrupting substances is cadmium (Cd), a ubiquitous toxic metal shown to act as a thyroid disruptor and carcinogen in both animals and humans. Multiple PubMed searches with core keywords were performed to identify and evaluate appropriate studies which revealed literature suggesting evidence for the link between exposure to Cd and histological and metabolic changes in the thyroid gland. Furthermore, Cd influence on thyroid homeostasis at the peripheral level has also been hypothesized. Both in vivo and in vitro studies revealed that a Cd exposure at environmentally relevant concentrations results in biphasic Cd dose-thyroid response relationships. Development of thyroid tumors following exposure to Cd has been studied mainly using in vitro methodologies. In the thyroid, Cd has been shown to activate or stimulate the activity of various factors, leading to increased cell proliferation and a reduction in normal apoptotic activity. Evidence establishing the association between Cd and thyroid disruption remains ambiguous, with further studies needed to elucidate the issue and improve our understanding of Cd-mediated effects on the thyroid gland.
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Cádmio/farmacologia , Disruptores Endócrinos/farmacologia , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Animais , Cádmio/toxicidade , Intoxicação por Cádmio , Disruptores Endócrinos/toxicidade , Exposição Ambiental/efeitos adversos , Humanos , Doenças da Glândula Tireoide/etiologia , Doenças da Glândula Tireoide/metabolismo , Testes de Função Tireóidea , Neoplasias da Glândula Tireoide/etiologia , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologiaRESUMO
Hepatotoxicity is one of the well-documented adverse health effects of polychlorinated biphenyls (PCBs)-persistent organic pollutants widely present in the environment. Although previous studies suggest possible role of oxidative stress, the precise mechanisms of PCB-induced ROS production in liver still remain to be fully assessed. The aim of this study was to evaluate the effects of different doses of PCBs on the parameters of oxidative stress and to investigate whether these effects are dose dependent. Furthermore, a comparison between calculated benchmark doses (BMD) and estimated NOAEL values for investigated parameters, was made. Six groups of male albino Wistar rats (7 animals per group) were receiving Aroclor 1254 dissolved in corn oil in the doses of 0.5, 1, 2, 4, 8, 16 mg PCBs/kg b.w./day by oral gavage during 28 days while control animals were receiving corn oil only. The following parameters of oxidative stress were analyzed in liver homogenates: superoxide dismutase activity, glutathione, malondialdehyde (MDA) and total protein thiol levels. Hepatic enzymes AST, ALT, ALP and protein albumin were also determined in serum as clinical parameters of liver function. Collected data on the investigated parameters were analyzed by the BMD method. The results of this study demonstrate that subacute exposure to PCBs causes induction of oxidative stress in liver with dose-dependent changes of the investigated parameters, although more pronounced adverse effects were observed on enzymatic than on non-enzymatic components of antioxidant protection. The obtained values for BMD and NOAEL support the use of BMD concept in the prediction of health risks associated with PCBs exposure. Furthermore, our results implicate possible use of MDA in PCBs risk assessment, since MDA was the most sensitive investigated parameter with calculated low critical effect dose of 0.07 mg/kg b.w.
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Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Bifenilos Policlorados/toxicidade , Animais , Relação Dose-Resposta a Droga , Fígado/metabolismo , Fígado/fisiopatologia , Testes de Função Hepática , Masculino , Nível de Efeito Adverso não Observado , Ratos , Ratos WistarRESUMO
Sulforaphane (SFN), which is a hydrolysis product from glucoraphanin, a compound found in cruciferous vegetables, has been studied for its potential health benefits, particularly in disease prevention and treatment. SFN has proven to be effective in combating different types of cancer by inhibiting the proliferation of tumors and triggering apoptosis. This dual action has been demonstrated to result in a reduction in tumor size and an enhancement of survival rates in animal models. SFN has also shown antidiabetic and anti-obesity effects, improving glucose tolerance and reducing fat accumulation. SFN's ability to activate Nrf2, a transcription factor regulating oxidative stress and inflammation in cells, is a primary mechanism behind its anticancerogenic and antidiabetic effects. Its antioxidant, anti-inflammatory, and anti-apoptotic properties are also suggested to provide beneficial effects against neurodegenerative diseases. The potential health benefits of SFN have led to increased interest in its use as a dietary supplement or adjunct to chemotherapy, but there are insufficient data on its efficacy and optimal doses, as well as its safety. This review aims to present and discuss SFN's potential in treating various diseases, such as cancer, diabetes, cardiovascular diseases, obesity, and neurodegenerative diseases, focusing on its mechanisms of action. It also summarizes studies on the pharmacological and toxicological potential of SFN in in vitro and animal models and explores its protective role against toxic compounds through in vitro and animal studies.
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This study aimed to assess the redox status and trace metal levels in 49 shoe industry workers (11 men and 38 women) occupationally exposed to a mixture of volatile organic compounds (VOCs), which includes aliphatic hydrocarbons, aromatic hydrocarbons, ketones, esters, ethers, and carboxylic acids. All measured VOCs were below the permitted occupational exposure limits. The control group included 50 unexposed participants (25 men and 25 women). The following plasma parameters were analysed: superoxide anion (O2 â¢-), advanced oxidation protein products (AOPP), total oxidative status (TOS), prooxidant-antioxidant balance (PAB), oxidative stress index (OSI), superoxide dismutase (SOD) and paraoxonase-1 (PON1) enzyme activity, total SH group content (SHG), and total antioxidant status (TAS). Trace metal levels (copper, zinc, iron, magnesium, and manganese) were analysed in whole blood. All oxidative stress and antioxidative defence parameters were higher in the exposed workers than controls, except for PON1 activity. Higher Fe, Mg, and Zn, and lower Cu were observed in the exposed vs control men, while the exposed women had higher Fe and lower Mg, Zn, and Cu than their controls. Our findings confirm that combined exposure to a mixture of VOCs, even at permitted levels, may result in additive or synergistic adverse health effects and related disorders. This raises concern about current risk assessments, which mainly rely on the effects of individual chemicals, and calls for risk assessment approaches that can explain combined exposure to multiple chemicals.
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Oligoelementos , Compostos Orgânicos Voláteis , Masculino , Humanos , Feminino , Antioxidantes/farmacologia , Cobre/toxicidade , Compostos Orgânicos Voláteis/toxicidade , Sapatos , Estresse Oxidativo , Oxirredução , Arildialquilfosfatase/metabolismo , Arildialquilfosfatase/farmacologiaRESUMO
The constant exposure of humans to a mixture of low doses of toxic substances, emerging from the daily emission of toxic dust containing various metals and organic compounds in electrical and electronic waste (e-waste) recycling areas, poses potential harmful effects on health and the environment. While individually recognized as endocrine disruptors affecting hormonal balance, the combined impact of these toxic substances in a mixture remains insufficiently explored, particularly in relation to reproductive health. Thus, the aim of this in silico analysis was to: (i) assess the relationship between the exposure to a mixture of DBDE, DBDPE, TBBPA, Pb, Cd and Ni and development of male and female reproductive system disorders; and (ii) demonstrate the ability of in silico toxicogenomic tools in revealing the potential molecular mechanisms involved in the mixture toxicity. As the main data-mining tool, Comparative Toxicogenomics Database (CTD) was used, along with the ToppGene Suite portal and GeneMANIA online server. Our analysis identified 5 genes common to all the investigated substances and linked to reproductive system disorders. Notably, the most prominent interactions among these genes were physical interactions (77.64 %). Pathway enrichment analysis identified oxidative stress response as the central disrupted molecular pathway linked to reproductive pathology in the investigated mixture, while our chemical-phenotype CTD analysis uncovered additional affected pathways - apoptosis, hormonal regulation, and developmental functions. These findings highlight an increased risk of reproductive system disorders associated with the exposure to the investigated mixture of toxic substances in electronic waste recycling areas, emphasizing the urgent need for attention to address this environmental health concern. Hence, future laboratory studies should prioritize investigating the specific genes and common mechanisms identified in this study.
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Resíduo Eletrônico , Disruptores Endócrinos , Masculino , Feminino , Humanos , Poeira/análise , Resíduo Eletrônico/análise , Disruptores Endócrinos/toxicidade , Metais , ReciclagemRESUMO
COVID-19 can cause a range of complications, including cardiovascular, renal, and/or respiratory insufficiencies, yet little is known of its potential effects in persons exposed to toxic metals. The aim of this study was to answer this question with in silico toxicogenomic methods that can provide molecular insights into COVID-19 complications owed to exposure to arsenic, cadmium, lead, mercury, nickel, and chromium. For this purpose we relied on the Comparative Toxicogenomic Database (CTD), GeneMANIA, and ToppGene Suite portal and identified a set of five common genes (IL1B, CXCL8, IL6, IL10, TNF) for the six metals and COVID-19, all of which code for pro-inflammatory and anti-inflammatory cytokines. The list was expanded with additional 20 related genes. Physical interactions are the most common between the genes affected by the six metals (77.64 %), while the dominant interaction between the genes affected by each metal separately is co-expression (As 56.35 %, Cd 64.07 %, Pb 71.5 %, Hg 81.91 %, Ni 64.28 %, Cr 88.51 %). Biological processes, molecular functions, and pathways in which these 25 genes participate are closely related to cytokines and cytokine storm implicated in the development of COVID-19 complications. In other words, our findings confirm that exposure to toxic metals, alone or in combinations, might escalate COVID-19 severity.
Assuntos
COVID-19 , Cádmio , Mercúrio , Humanos , Cádmio/toxicidade , Mercúrio/toxicidade , Chumbo/toxicidade , Simulação por Computador , SARS-CoV-2 , Arsênio/toxicidade , Níquel/toxicidade , Metais Pesados/toxicidade , Cromo/toxicidade , Citocinas , Interleucina-1beta/genética , Interleucina-8/genética , Toxicogenética , Interleucina-6/genética , Interleucina-10/genética , Fator de Necrose Tumoral alfa/genéticaRESUMO
Pesticides are crucial for crop protection and have seen a 50 % increase in use in the last decade. Besides preventing significant crop losses their use has raised health concerns due to consumer exposure through residues in food and water. The toxicity data from individual components is often used to assess overall mixture toxicity, but uncertainty persists in understanding the behaviors of individual chemicals within these mixtures. Assessing the risk of pesticide mixture exposure remains challenging, potentially leading to overestimation or underestimation of toxicity. This study aims to establish a possible link between exposure to a herbicide mixture and genotoxic effects, focusing on cancer development. Our analysis was focused on four herbicides glyphosate, nicosulfuron, S-metolachlor and terbuthylazine. To determine the link between genes associated with cancer development due to exposure to herbicide mixture, a CTD database tools were used. Through the ToppFun tool molecular function and biological process associated with genes common to the disease of interest and selected herbicides were evaluated. And finally, GeneMANIA was used in order to analyze the function and interaction between common genes of herbicide mixture. Among the 7 common genes for herbicide mixture and cancer development coexpression characteristics were dominant at 65.41 %, 22.14 % of annotated genes shared the same pathway and 7.88 % showed co-localization. Among six target genes involved in genetic disease development co-expression was dominant at 87.34 %, colocalization at 8.03 % and shared protein domains at 4.52 %. Comprehensive molecular analyses, encompassing genomics, proteomics, and pathway analysis, are essential to unravel the specific mechanisms involved in the context of the studied mixture and its potential carcinogenic effects.
Assuntos
Acetamidas , Glicina , Glifosato , Herbicidas , Compostos de Sulfonilureia , Triazinas , Zea mays , Herbicidas/toxicidade , Acetamidas/toxicidade , Glicina/análogos & derivados , Glicina/toxicidade , Triazinas/toxicidade , Compostos de Sulfonilureia/toxicidade , Zea mays/genética , Neoplasias/induzido quimicamente , Neoplasias/genética , Piridinas/toxicidade , Simulação por Computador , HumanosRESUMO
This study explored the effect of a toxic metal(oid) mixture (cadmium, lead, arsenic, mercury, chromium, and nickel) on thyroid function in Wistar rats exposed for 28 or 90 days. Dose levels were determined based on prior human-biomonitoring investigation. The experiment included control (male/female rats, 28 and 90 days) and treated groups, reflecting the lower confidence limit of the Benchmark Dose (BMDL) for hormone levels (M1/F1, 28 and 90 days), median concentrations (M2/F2, 28 and 90 days), 95th percentile concentrations (M3/F3, 28 and 90 days) measured in a human study, and reference values for individual metals extracted from the literature (M4/F4, 28 days only). Blood and thyroid gland samples were collected at the experimental termination. Serum TSH, fT3, fT4, T3, and T4 levels were measured, and SPINA-GT and SPINA-GD parameters were calculated. In silico analysis, employing the Comparative Toxicogenomic Database and ToppGene Suite portal, aimed to reveal molecular mechanisms underlying the observed effects. Results showed greater sensitivity in the female rats, with significant effects observed at lower doses. Subacute exposure increased TSH, fT3, and T3 levels in females, while subchronic exposure in males decreased TSH and fT3 levels and increased fT4. Subacute exposure induced changes even at allegedly safe doses, emphasizing potential health risks. Histological abnormalities were observed in all the treated groups. In silico findings suggested that toxic metal exposure contributes to thyroid disorders via oxidative stress, disruption of micronutrients, interference with hormone synthesis, and gene expression dysregulation. These results indicate that seemingly safe doses in single-substance research can adversely affect thyroid structure and function when administered as a mixture. These findings highlight the complex impact of toxic metal exposure on thyroid health, emphasizing that adhering to accepted safety limits for single-substance research fails to account for adverse effects on thyroid structure and function upon exposures to metal mixtures.