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Mariele Feiffer Charão,1,2 Caroline Souto,2 Natália Brucker,1,2 Anelise Barth,1,2 Denise S Jornada,1,3 Daiandra Fagundez,4 Daiana Silva Ávila,4 Vera L Eifler-Lima,1,5 Silvia S Guterres,1,3 Adriana R Pohlmann,1,6 Solange Cristina Garcia1,21Post-Graduate Programme in Pharmaceutical Sciences, 2Laboratory of Toxicology (LATOX), Department of Analysis, Pharmacy Faculty, 3Department of Production and Control of Drugs, Pharmacy Faculty, Federal University of Rio Grande do Sul, Porto Alegre, 4Research Group in Biochemistry and Toxicology in Caenorhabditis elegans (GBToxCE), Federal University of Pampa – UNIPAMPA, Uruguaiana, 5Laboratory of Medical Synthesis Organic (LaSOM), Pharmacy Faculty, 6Department of Organic Chemistry, Chemistry Institute, Federal University of Rio Grande do Sul, Porto Alegre, RS, BrazilAbstract: Caenorhabditis elegans is an alternative in vivo model that is being successfully used to assess the pharmacological and toxic effects of drugs. The exponential growth of nanotechnology requires the use of alternative in vivo models to assess the toxic effects of theses nanomaterials. The use of polymeric nanocapsules has shown promising results for drug delivery. Moreover, these formulations have not been used in cases of intoxication, such as in treatment of paraquat (PQ) poisoning. Thus, the use of drugs with properties improved by nanotechnology is a promising approach to overcome the toxic effects of PQ. This research aimed to evaluate the absorption of rhodamine B-labeled melatonin (Mel)-loaded lipid-core nanocapsules (LNC) by C. elegans, the application of this model in nanotoxicology, and the protection of Mel-LNC against PQ damage. The formulations were prepared by self-assembly and characterized by particle sizing, zeta potential, drug content, and encapsulation efficiency. The results demonstrated that the formulations had narrow size distributions. Rhodamine B-labeled Mel-LNC were orally absorbed and distributed in the worms. The toxicity assessment of LNC showed a lethal dose 50% near the highest dose tested, indicating low toxicity of the nanocapsules. Moreover, pretreatment with Mel-LNC significantly increased the survival rate, reduced the reactive oxygen species, and maintained the development in C. elegans exposed to PQ compared to those worms that were either untreated or pretreated with free Mel. These results demonstrated for the first time the uptake and distribution of Mel-LNC by a nematode, and indicate that while LNC is not toxic, Mel-LNC prevents the effects of PQ poisoning. Thus, C. elegans may be an interesting alternative model to test the nanocapsules toxicity and efficacy.Keywords: C. elegans, nanotoxicology, rhodamine B-labeled polymer

Diazepam (DZP) is a sedative medication prescribed to treat anxiety and as a sleep inducer, although its residual effects are unfavorable to patients. Nanotechnology represents a tool to improve the pharmacological characteristics of drugs, reducing their side effects. This study aimed to develop and characterize DZP nanocapsules and to evaluate their toxicity in alternative models and the hypnotic-sedative effect in mice. Nanocapsules were prepared by the nanoprecipitation method and properly characterized. Long-term and accelerated stability studies were performed. The in vitro release profile was determined by diffusion in Franz cells. The safety of the formulation was evaluated in the Caenorhabditis elegans (C. elegans) and the oral acute toxicity in mice. Pharmacological evaluation was performed using thiopental-induced sleeping time. DZP was successfully incorporated into Poly-(ɛ-caprolactone) (PCL) nanocapsules, with high entrapment efficiency. The nanocapsule did not affect the development or survival of C. elegans, different from the free drug, which affected the nematode development at the higher tested dose. No signs of toxicity, nor body mass or feed consumption changes were observed during the 14 days evaluated. Finally, this innovative formulation carrying DZP can produce a hypnotic-effect at a reduced dose compared to the free drug, with no toxicity in alternative models., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Alcohol Use Disorder (AUD) is a highly prevalent condition worldwide that produces a wide range of pathophysiological consequences, with a critical impact on health and social issues. Alcohol influences gene expression through epigenetic changes mainly through DNA methylation. In this sense, levels of 5-methylcytosine (5-mC), namely Global DNA methylation (GMe), which can be influenced by environmental and hormonal effects, represent a putative biological mechanism underlying alcohol effects. Our aim was to investigate the influence of AUD diagnosis and alcohol patterns (i.e., years of addiction, use in the last 30 days, and alcohol severity) on GMe levels. The sample consisted of 256 men diagnosed with AUD and 361 men without AUD. DNA samples from peripheral blood were used to assess GMe levels, measured through the levels of 5-mC using high-performance liquid chromatography. Results from multiple linear regression analysis indicated that the presence of AUD was associated with lower GMe levels (beta=-0.155, p=0.011). Other alcohol-related outcomes were not associated with DNA methylation. Our findings are consistent with the hypothesis that the impact of chronic and heavy alcohol use in GMe could be a potential mechanism mediating the multiple organ damages related to AUD.

Background: Coal and coal ash present inorganic elements associated with negative impacts on environment and human health. The objective of this study was to compare the toxicity of coal and coal ash from a power plant, assess their inorganic components, and investigate the biological impacts and potential mechanisms through in vitro and in vivo testing., Methods: Particle-Induced X-ray Emission method was used to quantify inorganic elements and the toxicity was evaluated in Caenorhabditis elegans and Daphnia magna in acute and chronic procedures. The genotoxic potential was assessed using alkaline and FPG-modified Comet assay in HepG2 cells and mutagenicity was evaluated using Salmonella/microsome assay in TA97a, TA100, and TA102 strains., Results: Inorganic elements such as aluminum (Al) and chromium (Cr) were detected at higher concentrations in coal ash compared to coal. These elements were found to be associated with increased toxicity of coal ash in both Caenorhabditis elegans and Daphnia magna. Coal and coal ash did not induce gene mutations, but showed genotoxic effects in HepG2 cells, which were increased using the FPG enzyme, indicating DNA oxidative damage., Conclusions: The combined findings from bioassays using C. elegans and D. magna support the higher toxicity of coal ash, which can be attributed to its elevated levels of inorganic elements. The genotoxicity observed in HepG2 cells confirms these results. This study highlights the need for continuous monitoring in areas affected by environmental degradation caused by coal power plants. Additionally, the analysis reveals significantly higher concentrations of various inorganic elements in coal ash compared to coal, providing insight into the specific elemental composition contributing to its increased toxicity., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier GmbH. All rights reserved.)

Urbanization and agricultural activities increased environmental contaminants. Integrated analysis of water parameters and bioassays represents an essential approach to evaluating aquatic resource quality. This study aimed to assess water quality by microbiological and physicochemical parameters as well as the toxicological effects of water samples on the Ames test and Caenorhabditis elegans model. Samples were collected during (collection 1) and after (collection 2) pesticide application in the upper (S1), middle (S2), and lower (S3) sections of the Rolante River, southern Brazil. Metals were determined by GFAAS and pesticides by UPLC-MS/MS. Bioassays using the Ames test and the nematode C. elegans were performed. Levels of microbiological parameters, as well as Mn and Cu were higher than the maximum allowed limits established by legislation in collection 2 compared to collection 1. The presence of pesticide was observed in both collections; higher levels were found in collection 1. No mutagenic effect was detected. Significant inhibition of body length of C. elegans was found in collection 1 at S2 ( P  < 0.001) and S3 ( P  < 0.001) and in collection 2 at S2 ( P  = 0.004). Comparing the same sampling site between collections, a significant difference was found between the site of collection (F(3,6)=8.75, P  = 0.01) and the time of collection (F(1,2)=28.61, P  = 0.03), for the S2 and S3 samples. C. elegans model was useful for assessing surface water quality/toxicity. Results suggest that an integrated analysis for the surface water status could be beneficial for future approaches., Competing Interests: There are no conflicts of interest to declare., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Minoxidil is regularly prescribed for alopecia, and its therapeutic potential has expanded in recent times. However, few studies have been conducted to evaluate its toxicity, and controversial findings regarding its mutagenic activities remain unsolved. This study aimed to access cytotoxic, genotoxic, and mutagenic properties of minoxidil using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay, comet assay, and micronucleus test in mouse fibroblast (L929) cells and its point mutation induction potential in the Salmonella/microsome assay. Furthermore, an in vivo toxicity assessment was conducted in Caenorhabditis elegans. Minoxidil showed cytotoxicity at 2.0 mg/mL in MTT assay. Genotoxicity was observed after 3 h treatment in L929 cells using comet assay. No mutagenic effect was observed in both the micronucleus test and the Salmonella/microsome assay. The lethal dose 50 in C. elegans was determined to be 1.75 mg/mL, and a delay in body development was detected at all concentrations. In conclusion, minoxidil induces DNA damage only in early treatment, implying that this DNA damage may be repairable. This observation corroborates the absence of mutagenic activities observed in L929 cells and Salmonella typhimurium strains. However, the toxicity of minoxidil was evident in both C. elegans and L929 cells, underscoring the need for caution in its use., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Introduction: The use of dried capillary microsamples for clinical chemistry testing is an interesting alternative to conventional phlebotomy. Sampling devices capable to produce plasma from whole blood application are particularly useful. The aim of this study was to validate theHealthID PSDmicrosampling device for the determination of cholesterol (CHOL), high-density lipoprotein (HDL), triglycerides (TRIG), creatinine (CRE), and glycated hemoglobin (HbA 1 c) after collection of capillary blood., Methods: Dried blood and plasma extracts were analyzed using modified methods in an open-channel biochemistry analyzer. The plasma volume in the extracts was corrected by the concentration of chloride (CL). Linearity, imprecision, bias, stability, and comparability to conventional samples were evaluated., Results: Dried plasma assays presented total error (TE) within acceptable limits. The analytes were stable for up to 14 days at 40 °C. Predicted serum concentrations of CHO, HDL, TRI, and CRE and predicted whole blood levels of HbA 1 c, using dried extracts measurements, did not presented systematic or proportional differences to serum and whole blood levels., Conclusions: Dried sample extracts obtained with capillary blood applied to the HealthID PSD allowed the determination of CHO, HDL, TRI, CRE, and HbA 1 c, as well as the calculation of LDL level, using only 5 drops of blood. This sampling strategy can be useful for population screening programs, particularly in Developing Countries., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: The authors of the manuscript disclose the following: G.L. is an employee of HealthID Lab; M.F.C. and R.L. have stock ownership in HealthID Lab., (Copyright © 2023 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)

Introduction: The use of dried blood spots (DBS) has gained interest in the field of therapeutic drug monitoring (TDM) due to its potential advantages, such as minimally invasive capillary blood collection, potential stabilization of drugs and metabolites at room or high temperatures, and lower biohazard, allowing for inexpensive storage and transportation. However, there are several drawbacks to the clinical use of DBS in TDM, mostly related to hematocrit (Hct) effects, differences between venous and capillary blood concentrations, among others, that must be evaluated during analytical and clinical method validation., Area Covered: This review focuses on the most recent publications on the applications of DBS sampling for TDM (2016-2022), with a special focus on the challenges presented by this alternative sampling strategy, as well as the opportunities for clinical applications. Real-life studies presenting clinical applications were reviewed., Expert Opinion: With the availability of method development and validation guidelines for DBS-based methods in TDM, higher levels of assay validation standardization have been achieved, expanding the clinical applications of DBS sampling in patient care. New sampling devices that overcome the limitations of classical DBS, such as the Hct effects, will further encourage the use of DBS in routine TDM.

Liposomes are among the most studied nanostructures. They are effective carriers of active substances both in the clinical field, such as delivering genes and drugs, and in the food industry, such as promoting the controlled release of bioactive substances, including food preservatives. However, toxicological screenings must be performed to ensure the safety of nanoformulations. In this study, the nematode Caenorhabditis elegans was used as an alternative model to investigate the potential in vivo toxicity of nanoliposomes encapsulating the antimicrobial peptide nisin. The effects of liposomes containing nisin, control liposomes, and free nisin were evaluated through the survival rate, lethal dose (LD 50 ), nematode development rate, and oxidative stress status by performing mutant strain, TBARS, and ROS analyses. Due to its low toxicity, it was not possible to experimentally determine the LD 50 of liposomes. The survival rates of control liposomes and nisin-loaded liposomes were 94.3 and 73.6%, respectively. The LD 50 of free nisin was calculated as 0.239 mg mL -1 . Free nisin at a concentration of 0.2 mg mL -1 significantly affected the development of C. elegans , which was 25% smaller than the control and liposome-treated samples. A significant increase in ROS levels was observed after exposure to the highest concentrations of liposomes and free nisin, coinciding with a significant increase in catalase levels. The treatments induced lipid peroxidation as evaluated by TBARS assay. Liposome encapsulation reduces the deleterious effect on C. elegans and can be considered a nontoxic delivery system for nisin.

Background: Vortioxetine hydrobromide (VXT), a new therapeutic option in the treatment of major depressive disorder, is a poorly soluble drug, and instability under stress conditions has been reported. The aim of the present study was to prepare VXT liposomes (VXT-Ls) with an antidepressant-like effect, to improve drug stability and reduce toxicity of the free drug., Methods: Liposomes were prepared using the thin lipid film hydration method and properly characterized. Forced degradation studies were conducted in photolytic and oxidative conditions. The cytotoxicity was evaluated in VERO cells through MTT assay and in vivo toxicity was assessed in mice. The antidepressant-like effect in mice was confirmed using the open-field test paradigm and tail suspension test., Results: The optimized VXT-Ls have multilamellar vesicles with an average size of 176.74 nm ± 2.43. The liposomal formulation increased the stability of VXT. VERO cell viability was maintained at around 40% when the VXT-Ls were tested at higher concentrations and no signs of acute toxicity were observed in mice. The antidepressant-like effect was effective, for VXT-Ls, at doses ranging from 2.5 mg/kg to 10 mg/kg, measured by the tail suspension test in mice. The non-liposomal formulation was effective at a dose of 10 mg/kg. The open field test was performed and any unspecific changes in locomotor activity were revealed., Conclusions: Liposomes seem to be a promising alternative for an oral VXT formulation at lower doses (2.5 mg/kg)., (© 2022. The Author(s) under exclusive licence to Maj Institute of Pharmacology Polish Academy of Sciences.)

Formaldehyde (FA) is a xenobiotic air pollutant and its universal distribution causes a widespread exposure to humans. This review aimed to bring updated information concerning FA toxicity in humans and animals based on in vitro and in vivo studies from 2013 to 2019. Researches were carried out in Pubmed, Scopus, and Science Direct databases to determine the effects of FA exposure on inflammation, oxidative stress and genotoxicity in experimental studies with animals (rats and mice) and humans. Besides, in vitro studies assessing FA cytotoxicity focusing on cell viability and apoptosis in different cell line cultures were reviewed. Studies with humans gave evidence regarding significant deleterious effects on health associated to chronic FA occupational exposure. Evaluations carried out in experimental studies showed toxic effects on different organs as lung, upper respiratory tract, bone marrow and brain as well as in cells. In summary, this study demonstrates that knowing the mechanisms underlying FA toxicity is essential to understand the deleterious effects that this xenobiotic causes on biological systems.

Genetic and environmental factors contribute to the etiology of Attention Deficit-Hyperactivity Disorder (ADHD). In this sense, the study of epigenetic mechanisms could contribute to the understanding of the disorder's neurobiology. Global DNA methylation (GMe) evaluated through 5-methylcytosine levels could be a promising epigenetic biomarker to capture long-lasting biological effects in response to environmental and hormonal changes. We conducted the first assessment of GMe levels in subjects with ADHD (n = 394) and its main comorbidities in comparison to populational controls (n = 390). Furthermore, given the high genetic contribution to ADHD (heritability of 80%), polygenic risk scores (PRS) were calculated to verify the genetic contribution to GMe levels in ADHD and the comorbidities associated with GMe levels. The GMe levels observed in patients were lower than controls (P = 1.1e-8), with women being significantly less globally methylated than men (P = 0.002). Regarding comorbidities, the presence of bipolar disorder (BD) among patients with ADHD was associated with higher methylation levels compared to patients with ADHD without BD (P = 0.031). The results did not change when pharmacological treatment was accounted for in the analyses. The ADHD and BD most predictive PRSs were negatively (P = 0.0064) and positively (P = 0.0042) correlated with GMe, respectively. This study is the first to report an association between GMe, ADHD, and its comorbidity with BD and associations between PRSs for specific psychiatric disorders and GMe. Our findings add to previous evidence that GMe may be a relevant piece in the psychiatric disorders' etiological landscape., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

Agriculture activities have increased the concentration of pesticides and metals in the environment. The excessive use of pesticides can generate an environmental impact and contribute to the development of human diseases. This study aimed to determine the presence of pesticides and metals in water samples collected in the Brazilian rural area in two different periods (before and after pesticide application) and to evaluate the alternative bioassays Lactuca sativa , Allium cepa , and Caenorhabditis elegans to monitoring toxicity in human drinking water samples. Eight sites in the rural area were selected and water samples were collected in two different periods of the year (before and after pesticide application). The presence of the pesticides was determinated by ultra-high performance liquid chromatography-tandem mass spectrometry and metals by inductively coupled plasma mass spectrometry. The potential toxicity of the water samples was performed with three different alternatives in vivo models ( L. sativa , A. cepa , and C. elegans ). Fifty-seven pesticides were analyzed and, according to the results, the most found ones were clomazone, atrazine, tebuconazole, metconazole, pyrimethanil, and carbofuran-3-hydroxide, which is a metabolic degradation product of insecticide carbofuran. The most detected metals were Cu, Cr, Mg, Fe, and Mn. The assays with L. sativa and A. cepa showed alterations in the period after pesticide application, while C. elegans presented changes in both periods compared to the same collection sites. These results indicate that bioassays, especially C. elegans , could be complementary and useful tools for monitoring the toxicity in drinking water samples., (© The Author(s) 2021. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

There is an increasing body of knowledge on the influence of differential DNA methylation of specific genomic regions in psychiatric disorders. However, fewer studies have addressed global DNA methylation (GMe) levels. GMe is an estimative of biological functioning that is regulated by pervasive mechanisms able to capture the big picture of metabolic and environmental influences upon gene expression. In the present perspective article, we highlighted evidence for the relationships between cortisol and sex hormones and GMe in psychiatric disorders. We argue that the far-reaching effects of cortisol and sexual hormones on GMe may lie on the pathways linking stress and mental health. Further research on these endocrine-epigenetic links may help to explain the role of environmental stress as well as sex differences in the prevalence of psychiatric disorders.

Formaldehyde (FA) exposure has been proven to increase the risk of asthma and cancer. This study aimed to evaluate for 28 days the FA inhalation effects on oxidative stress, inflammation process, genotoxicity, and global DNA methylation in mice as well as to investigate the potential protective effects of melatonin. For that, analyses were performed on lung, liver and kidney tissues, blood, and bone marrow. Bronchoalveolar lavage was used to measure inflammatory parameters. Lipid peroxidation (TBARS), protein carbonyl (PCO), non-protein thiols (NPSH), catalase activity (CAT), comet assay, micronuclei (MN), and global methylation were determined. The exposure to 5-ppm FA resulted in oxidative damage to the lung, presenting a significant increase in TBARS and NO levels and a decrease in NPSH levels, besides an increase in inflammatory cells recruited for bronchoalveolar lavage. Likewise, in the liver tissue, the exposure to 5-ppm FA increased TBARS and PCO levels and decreased NPSH levels. In addition, FA significantly induced DNA damage, evidenced by the increase of % tail moment and MN frequency. The pretreatment of mice exposed to FA applying melatonin improved inflammatory and oxidative damage in lung and liver tissues and attenuated MN formation in bone marrow cells. The pulmonary histological study reinforced the results observed in biochemical parameters, demonstrating the potential beneficial role of melatonin. Therefore, our results demonstrated that FA exposure with repeated doses might induce oxidative damage, inflammatory, and genotoxic effects, and melatonin minimized the toxic effects caused by FA inhalation in mice., (© The Author(s) 2020. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

There is a well-recognized association between environmental air pollution exposure and several human diseases. However, the relationship between diseases related to occupational air pollution exposure on roads and high levels of traffic-related air pollutants (TRAPs) is less substantiated. Biomarkers are essential tools in environmental and occupational toxicology, and studies on new biomarkers are increasingly relevant due to the need to determine early biomarkers to be assessed in exposure conditions. This review aimed to investigate the main advances in the biomonitoring of subjects occupationally exposed to air pollution, as well as to summarize the biomarkers of exposure, effect, and susceptibility. Furthermore, we discuss how biomarkers could be used to complement the current application of methods used to assess occupational exposures to xenobiotics present in air pollution. The databases used in the preparation of this review were PubMed, Scopus, and Science Direct. Considering the significant deleterious effects on health associated with chronic occupational exposure to xenobiotics, this topic deserves attention. As it is difficult to avoid occupational exposure to TRAPs, biomonitoring should be applied as a strategy to reduce the toxic effects of workplace exposure., (© 2020 John Wiley & Sons, Ltd.)

Toluene is a highly volatile organic solvent present in gasoline. Exposure mainly occurs by absorption via the pulmonary tract and easily reaches the central nervous system, which causes toxic effects. Toluene toxicity has been described but not well established. The present work aimed to evaluate the effects of airborne exposure to toluene, the in vivo model Caenorhabditis elegans was assessed to determine whether nematode could be used to evaluate the effects of exposure to toluene and the possible mechanisms of toxicity of the solvent. Worms at the first or fourth larval stages were exposed to toluene for 48 or 24 h, respectively, in a laboratory-developed vapor chamber at concentrations of 450, 850, 1250 and 1800 ppm. We observed increases in worm mortality and significant developmental delays that occurred in a concentration-dependent manner. An increased incidence of apoptotic events in treated germline cells was shown, which was consistent with observed reductions in reproductive capacity. In addition, toluene promoted significant behavioural changes affecting swimming movements and radial locomotion, which were associated with changes in the fluorescence intensity and morphology of GABAergic and cholinergic neurons. We conclude that toluene exposure was toxic to C. elegans, with effects produced by the induction of apoptosis and neuronal damage., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: Gasoline is a complex mixture of saturated and unsaturated hydrocarbons, in which aromatic compounds, such as BTX (benzene, toluene, and xylene) feature as the main constituents. Simultaneous exposure to these aromatic hydrocarbons causes a significant impact on benzene toxicity. In order to detect early alterations caused in gasoline station attendants exposed to BTX compounds, immunological, inflammatory, and oxidative stress biomarkers were evaluated., Methods: A total of 66 male subjects participated in this study. The gasoline station attendants (GSA) group consisted of 38 gasoline station attendants from Rio Grande do Sul, Brazil. The non-exposed group consisted of 28 subjects who were non-smokers and who had no history of occupational exposure. Environmental and biological monitoring of BTX exposure was performed using blood and urine., Results: The GSA group showed increased BTX concentrations in relation to the non-exposed group (p < 0.001). The GSA group showed elevated protein carbonyl (PCO) levels and pro-inflammatory cytokines, decreased expression of CD80 and CD86 in monocytes, and reduced glutathione S-transferase (GST) activity compared to the non-exposed group (p < 0.05). BTX levels and trans,trans-muconic acid levels were positively correlated with pro-inflammatory cytokines and negatively correlated with interleukin-10 contents (p < 0.001). Increased levels of pro-inflammatory cytokines were accompanied by increased PCO contents and decreased GST activity (p < 0.001). Furthermore, according to the multiple linear regression analysis, benzene exposure was the only factor that significantly contributed to the increased pro-inflammatory cytokines (p < 0.05)., Conclusions: Taken together, these findings show the influence of exposure to BTX compounds, especially benzene, on the immunological, inflammatory, and oxidative stress biomarkers evaluated. Furthermore, the data suggest the relationship among the evaluated biomarkers of effect, which could contribute to providing early signs of damage to biomolecules in subjects occupationally exposed to BTX compounds.

Background: Melatonin has been described in the literature as a potent antioxidant. However, melatonin presents variable, low bioavailability and a short half-life. The use of polymeric nanoparticulated systems has been proposed for controlled release. Thus, the purpose of this study was to investigate the action of melatonin-loaded lipid-core nanocapsules (Mel-LNC) in the antioxidant system of Caenorhabditis elegans, and the possible protective effect of this formulation against lipid peroxidation caused by paraquat (PQ)., Methods: The suspensions were prepared by interfacial deposition of the polymer and were physiochemically characterized. C. elegans N2 wild type and transgenic worm CF1553, muls84 [sod-3p::gfp; rol6(su1006)] were obtained from the Caenorhabditis Genetics Center (CGC). The worms were divided into 5 groups: Control, PQ 0.5 mM, PQ 0.5 mM + Mel-LNC 10 μg/mL, PQ + unloaded lipid-core nanocapsules (LNC), and PQ + free melatonin (Mel) 10 μg/mL. The lipid peroxidation was assessed through thiobarbituric acid (TBARS) levels and the fluorescence levels of the transgenic worms expressing GFP were measured., Results: The LNC and Mel-LNC presented a bluish-white liquid, with pH values of 5.56 and 5.69, respectively. The zeta potential was - 6.4 ± 0.6 and - 5.2 ± 0.2, respectively. The mean particle diameter was 205 ± 4 nm and 203 ± 3 nm, respectively. The total melatonin content was 0.967 mg/ml. The TBARS levels were significantly higher in the PQ group when compared to the control group (p < 0.001). Mel-LNC reduced TBARS levels to similar levels found in the control group. Moreover, only Mel-LNC significantly enhanced the SOD-3 expression (p < 0.05). Mel-LNC was capable of protecting C. elegans from lipid peroxidation caused by PQ and this was not observed when free melatonin was used. Moreover, Mel-LNC increased the fluorescence intensity of the transgenic strain that encodes the antioxidant enzyme SOD-3, demonstrating a possible mechanism of protection from PQ-induced damage., Conclusion: These findings demonstrated that melatonin, when associated with nanocapsules, had improved antioxidant properties and the protective activity against PQ-induced lipid peroxidation could be associated with the activation of antioxidant enzymes by Mel-LNC in C. elegans.

Formaldehyde (FA) is a carcinogenic aldehyde illegally added to creams as a hair straightening agent for the Brazilian blowout (BB). This study aimed to investigate the possible effects of occupational exposure to FA on global DNA methylation in salon workers with different exposure levels. FA exposure was monitored using environmental and biological measurements. The study included 49 salon workers divided by FA levels in the workplace into group A (FA < 0.01 ppm; n = 8), group B (0.03 ppm < FA < 0.06 ppm; n = 15), and group C (0.08 ppm < FA < 0.24 ppm; n = 26). The global DNA methylation levels were 3.12%, 4.55%, and 4.29% for groups A, B, and C, respectively, with statistically higher values for groups B and C compared to group A (p = 0.002). A correlation was found between FA in passive samplers and global DNA methylation (r s  = 0.307, p = 0.032). Additionally, when only taking into account the hairdressers that performed the BB on clients instead of the whole group, a stronger correlation was observed between FA in personal passive samplers and global DNA methylation (r s  = 0.764, p = 0.006). For the first time, an increase in DNA methylation was observed in subjects occupationally exposed to FA. In conclusion, our results indicated that even low levels of FA exposure could cause a disturbance in DNA methylation, leading to epigenetic changes, which is associated with cancer development. These data suggest a possible contribution of FA to cancer development through occupational exposure.

This review aimed to investigate possible protective or deleterious effects of polyphenol-rich foods (PRF) on chronic diseases, e.g. cardiovascular, and in pregnant women, along with their antioxidant and anti-inflammatory action. A great variety of foods and beverages, such as herbal teas, grape and orange derivatives, dark chocolate, and many others contain high concentrations of flavonoids and are freely consumed by the general population. In humans, PRF consumption reduces lipid peroxidation, and several studies have shown a positive correlation between an increased consumption of PRF and a decrease in the incidence of cardiovascular disease. On the other hand, current studies have suggested that maternal ingestion of PRF, especially during the third trimester of pregnancy, could be associated to fetal ductal constriction (DC). Fetuses exposed to this type of diet show higher ductal velocities and lower pulsatility indexes, as well as larger right ventricles than those exposed to minimal amounts of these substances. The underlying mechanism involved in these conditions has not been entirely elucidated, but it seems to be a result of the antioxidant and anti-inflammatory effects of polyphenols by some pathway. Furthermore, taking into account the deleterious effect in late-pregnancy against the numerous positive effects associated to polyphenols, this dual behavior deserves attention particularly to control the dietary ingestion of PRF during gestation. In this line, same PRF, natural constituents of human diet, may represent risk to fetal in late pregnancy compared to the use of nonsteroidal anti-inflammatory drugs.

The aging phenomenon is associated with oxidative stress damage in biomolecules, especially DNA. 5-Methyltetrahydrofolate (5-MTHF), the active folate form, plays a pivotal role in maintaining genomic integrity. However, recently it was associated with cancer development. In Brazil, there are folic acid enriched foods, such as flour, making the general population chronically exposed to folates. Therefore, the aim of this study was to investigate whether erythrocytes 5-MTHF levels were associated with age-related DNA damage in two groups (elderly and young subjects). Additionally, a study in Caenorhabditis elegans , an in vivo alternative model, was performed to verify if 5-MTHF presents a pro-oxidant effect. A total of 50 elderly and 25 young subjects participated in this study, which analyzed whole blood DNA damage, plasma carbonyl proteins (PCO), and erythrocytes 5-MTHF levels. In addition, ROS and RNS production, survival rate, and lifespan were performed in C. elegans exposed to 5-MTHF. Blood 5-MTHF levels and DNA damage were increased in the elderly compared to the young group. A positive association was found between 5-MTHF levels and DNA damage, and between DNA damage and PCO levels, suggesting an oxidative cause of damage associated with the active folate form. In an experimental study it was observed that 5-MTHF increased ROS production in C. elegans , in a dose dependent manner, while survival rate and life span were not affected at the test doses. These findings suggest that 5-MTHF, the active folate form, may be involved in DNA damage in the elderly. This damage could be a result of oxidative stress, as observed in the in vivo alternative model; however, more studies are necessary to prove our present results.

Women are employed in increasing numbers as gasoline station attendants, a work category with risk of exposure to benzene. We have assessed the effect of gender on biomarkers of occupational benzene exposure. Gasoline station attendants (20 men and 20 women) and 40 control individuals (20 men and 20 women) with no history of occupational benzene exposure were evaluated. Benzene exposure was monitoring by environmental and biological measurements. Urinary trans,trans-muconic acid levels, well-known genetic and hematological alterations linked to benzene exposure, and non-cancer effects on the immune, hepatic, and renal systems were investigated. Our results suggest a potential effect of gender on some effects of occupational benzene exposure, particularly the hematological parameters and trans,trans-muconic acid levels. Despite limitations of our study, our findings provide important considerations about occupational exposure of women to benzene and may contribute to the development of occupational protection standards., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Children may be environmentally exposed to several hazards. In order to evaluate the health of children living in a tobacco-producing region, different biomarkers of exposure and effect, as well as hematological parameters, were evaluated. Biomarkers of exposure to the following xenobiotics were assessed: pesticides, nicotine, toxic elements, and organic solvents. Oxidative damage markers malondialdehyde (MDA) and protein carbonyls (PCO), vitamin C, microalbuminuria (mALB) levels, and N-acetyl-β-D-glucosaminidase (NAG) activity were also evaluated. Peripheral blood samples and urine were collected from 40 children (6-12 years), at two different crop periods: in the beginning of pesticide applications (period 1) and in the leaf harvest (period 2). The Wilcoxon signed-rank test for paired data was used to evaluate the differences between both periods. Biomarkers of exposure cotinine in urine and blood chromium (Cr) levels were increased in period 1 when compared to period 2. Moreover, a significant reduced plasmatic activity of butyrylcholinesterase (BuChE) was observed in period 2 in relation to period 1. Blood Cr levels were above the recommended by WHO in both evaluations. The biomarkers MDA and PCO as well as the kidney dysfunction biomarker, mALB, presented levels significantly increased in period 1. Additionally, decreased lymphocytes and increased basophils were also observed. Cotinine was positively associated with PCO, and Cr was positively associated with PCO and MDA. The increased Cr levels were associated with decreased lymphocytes and increased basophils. Our findings demonstrate that children environmentally exposed to xenobiotics in rural area may present early kidney dysfunction, hematological alterations, as well as lipid and protein damages, associated with co-exposure to different xenobiotics involved in tobacco cultivation.

Therapeutic drug monitoring (TDM) relays in the availability of specialized laboratory assays, usually available in reference centers that are not accessible to all patients. In this context, there is a growing interest in the use of dried blood spot (DBS) sampling, usually obtained from finger pricks, which allows simple and cost-effective logistics in many settings, particularly in Developing Countries. The use of DBS assays to estimate plasma concentrations is highly dependent on the hematocrit of the blood, as well as the particular characteristics of the measured analyte. DBS assays require specific validation assays, most of them are related to hematocrit effects. In the present manuscript, the application of mass spectrometric assays for determination of drugs for TDM purposes in the last ten years is reviewed, as well as the particular validation assays for new DBS methods., (Copyright © 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)

Many acute poisonings lack effective and specific antidotes. Due to both intentional and accidental exposures, paraquat (PQ) causes thousands of deaths annually, especially by pulmonary fibrosis. Melatonin (Mel), when incorporated into lipid-core nanocapsules (Mel-LNC), has enhanced antioxidant properties. The effects of such a formulation have not yet been studied with respect to mitigation of PQ- induced cytotoxicity and DNA damage. Here, we have tested whether Mel-LNC can ameliorate PQ-induced toxicity in the A549 alveolar epithelial cell line. Physicochemical characterization of the formulations was performed. Cellular uptake was measured using nanocapsules marked with rhodamine B. Cell viability was determined by the MTT assay and DNA damage was assessed by the comet assay. The enzyme-modified comet assay with endonuclease III (Endo III) and formamidopyrimidine glycosylase (FPG) were used to investigate oxidative DNA damage. Incubation with culture medium for 24h did not alter the granulometric profile of Mel-LNC formulations. Following treatment (3 and 24h), red fluorescence was detected around the cell nucleus, indicating internalization of the formulation. Melatonin solution (Mel), Mel-LNC, and LNC did not have significant effects on cell viability or DNA damage. Pre-treatment with Mel-LNC enhanced cell viability and showed a remarkable reduction in % DNA in tail compared to the PQ group; this was not observed in cells pre-treated with Mel. PQ induces oxidative DNA damage detected with the enzyme-modified comet assay. Mel-LNC reduced this damage more effectively than did Mel. In summary, Mel-LNC is better than Mel at protecting A549 cells from the cytotoxic and genotoxic effects of PQ., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Introduction: Elucidation of effective biomarkers may provide tools for the early detection of biological alterations caused by benzene exposure and may contribute to the reduction of occupational diseases. This study aimed to assess early alterations on hematological and immunological systems of workers exposed to benzene., Methods: Sixty gasoline station attendants (GSA group) and 28 control subjects were evaluated. Environmental and biological monitoring of benzene exposure was performed in blood and urine. The potential effect biomarkers evaluated were δ-aminolevulinate dehydratase (ALA-D) activity, CD80 and CD86 expression in lymphocytes and monocytes, and serum interleukin-8 (IL-8). The influence of confounding factors and toluene co-exposure were considered., Results: Although exposures were below ACGIH (American Conference of Governmental Industrial Hygienists) limits, reduced ALA-D activity, decreased CD80 and CD86 expression in monocytes and increased IL-8 levels were found in the GSA group compared to the control subjects. Furthermore, according to multiple linear regression analysis, benzene exposure was associated to a decrease in CD80 and CD86 expression in monocytes., Conclusions: These findings suggest, for the first time, a potential effect of benzene exposure on ALA-D activity, CD80 and CD86 expression, IL-8 levels, which could be suggested as potential markers for the early detection of benzene-induced alterations., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Children are especially vulnerable to adverse effects of multiple metals exposure. The aim of this study was to assess some metals concentrations such as lead (Pb), arsenic (As), chromium (Cr), manganese (Mn) and iron (Fe) in whole blood, serum, hair and drinking water samples using inductively coupled plasma-mass spectrometry (ICP-MS) in rural and urban children. In addition, evaluate the adverse effects of multiple metals exposure on cognitive function and δ-aminolevulinate dehydratase (ALA-D) activity. The cognitive ability assessment was performed by the Raven's Colored Progressive Matrices (RCPM) test. The ALA-D activity and ALA-D reactivation index (ALA-RE) activity with DTT and ZnCl2 also were determined. Forty-six rural children and 23 urban children were enrolled in this study. Rural children showed percentile IQ scores in the RCPM test significantly decreased in relation to urban children. According to multiple linear regression analysis, the Mn and Fe in hair may account for the cognitive deficits of children. Manganese and Fe in hair also were positively correlated with Mn and Fe in drinking water, respectively. These results suggest that drinking water is possibly a source of metals exposure in children. ALA-D activity was decreased and ALA-RE with DTT and ZnCl2 was increased in rural children in comparison to urban children. Moreover, ALA-D inhibition was correlated with Cr blood levels and ALA-RE/DDT and ALA-RE/ZnCl2 were correlated with levels of Cr and Hg in blood. Thus, our results indicated some adverse effects of children's exposure to multiple metals, such as cognitive deficits and ALA-D inhibition, mainly associated to Mn, Fe, Cr and Hg., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Objective: Because we have previously demonstrated the relation between polyphenol-rich foods (PRF) consumption and ductus arteriosus constriction, in this work, pregnant sheep were submitted to oral PRF intake for 14 days to understand how this process occurs. Fetal Doppler echocardiography, oxidative and inflammatory biomarkers and total polyphenol excretion were evaluated., Results: The high polyphenol intake induced ductus arteriosus constriction by 71.6% increase in systolic (P = 0.001) and 57.8% in diastolic velocities (P = 0.002), and 18.9% decrease in pulsatility index (P = 0.033), along with 1.7-fold increase in total polyphenol excretion, 2.3-fold decrease in inflammatory mediator nitric oxide and following redox status changes (mean ± standard deviation): higher protein carbonyls (1.09 ± 0.09 and 1.49 ± 0.31), catalase (0.69 ± 0.39 and 1.44 ± 0.33) and glutathione peroxidase (37.23 ± 11.19 and 62.96 ± 15.03) in addition to lower lipid damage (17.22 ± 2.05 and 12.53 ± 2.11) and nonprotein thiols (0.11 ± 0.04 and 0.04 ± 0.01) found before and after treatment, respectively. Ductal parameters correlated to NOx , catalase, glutathione peroxidase and protein carbonyl., Conclusion: Our results highlight the need to reduce maternal PRF intake in late pregnancy to prevent fetal duct constriction through NO-mediated vasoconstrictive action of polyphenols., (© 2014 John Wiley & Sons, Ltd.)

Children's exposure to metals can result in adverse effects such as cognitive function impairments. This study aimed to evaluate some toxic metals and levels of essential trace elements in blood, hair, and drinking water in children from a rural area of Southern Brazil. Cognitive ability and δ-aminolevulinate dehydratase (ALA-D) activity were evaluated. Oxidative stress was evaluated as a main mechanism of metal toxicity, through the quantification of malondialdehyde (MDA) levels. This study included 20 children from a rural area and 20 children from an urban area. Our findings demonstrated increase in blood lead (Pb) levels (BLLs). Also, increased levels of nickel (Ni) in blood and increase of aluminum (Al) levels in hair and drinking water in rural children were found. Deficiency in selenium (Se) levels was observed in rural children as well. Rural children with visual-motor immaturity presented Pb levels in hair significantly increased in relation to rural children without visual-motor immaturity (p < 0.05). Negative correlations between BLLs and ALA-D activity and positive correlations between BLLs and ALA-RE activity were observed. MDA was significantly higher in rural compared to urban children (p < 0.05). Our findings suggest that rural children were co-exposed to toxic metals, especially Al, Pb and Ni. Moreover, a slight deficiency of Se was observed. Low performance on cognitive ability tests and ALA-D inhibition can be related to metal exposure in rural children. Oxidative stress was suggested as a main toxicological mechanism involved in metal exposure.

Aging is often accompanied by cognitive impairments and influenced by oxidative status and chemical imbalances. Thus, this study was conducted to examine whether age-related cognitive deficit is associated with oxidative damage, especially with inhibition of the enzyme delta-aminolevulinate dehydratase (ALA-D), as well as to verify the influence of some metals in the enzyme activity and cognitive performance. Blood ALA-D activity, essential (Fe, Zn, Cu, Se) and non-essential metals (Pb, Cd, Hg, As, Cr, Ni, V) were measured in 50 elderly and 20 healthy young subjects. Cognitive function was assessed by tests from Consortium to Establish a Registry for Alzheimer's Disease (CERAD) battery and other. The elderly group presented decreased ALA-D activity compared to the young group. The index of ALA-D reactivation was similar to both study groups, but negatively associated with metals. The mean levels of essential metals were within the reference values, while the most toxic metals were above them in both groups. Cognitive function impairments were observed in elderly group and were associated with decreased ALA-D activity, with lower levels of Se and higher levels of toxic metals (Hg and V). Results suggest that the reduced ALA-D activity in elderly can be an additional factor involved in cognitive decline, since its inhibition throughout life could lead to accumulation of the neurotoxic compound ALA. Toxic metals were found to contribute to cognitive decline and also to influence ALA-D reactivation.

Gas station attendants and taxi drivers are occupationally exposed to xenobiotics which may be harmful to their health. Atmospheric pollutants and benzene can lead to DNA damage. Genotoxicity and mutagenicity assays can be used to evaluate the effects of these pollutants. We have evaluated genotoxicity and mutagenicity in workers occupationally exposed to xenobiotics, by application of the 8-hydroxy-2-deoxyguanosine (8-OHdG), comet, and micronucleus (MN) assays. Biomarkers of benzene and carbon monoxyde exposure were also measured: urinary t,t-muconic acid (t,t-MA) and carboxyhaemoglobin (COHb) in whole blood, respectively. The study groups comprised 43 gas station attendants (GSA), 34 taxi drivers (TD), and 22 persons without known occupational exposures (NE). Levels of t,t-MA in the GSA group were significantly elevated compared to the NE group (p<0.001), however these levels were below of levels established by ACGIH (American Conference of Governmental Industrial Hygienists). COHb levels were not significantly different between the TD and NE groups (p>0.05). DNA damage index (DI) and 8-OHdG levels were significantly higher for both the GSA and TD groups, compared to the NE group (p<0.001), but MN frequencies were not elevated. Spearman correlation analysis showed that the frequency of MN was positively correlated with 8-OHdG. A positive correlation between DNA DI levels and 8-OHdG was also observed. In conclusion, our results indicated that low levels of occupational exposure to benzene and atmospheric pollutants may be linked to genotoxicity and oxidative DNA damage., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Consistent evidence has indicated that the exposure to environmental air pollution increases the risk of cardiovascular disease. This study aimed to evaluate the possible effects of occupational exposure to air pollution, especially to polycyclic aromatic hydrocarbons (PAHs), and the influence of co-morbidities on the atherosclerotic process and inflammation. For that, biomarkers of exposure such as 1-hydroxypyrene urinary, oxidative damage and markers of cardiovascular risk were determined in plasma, serum and blood. In addition, inflammation models such as carotid intima-media thickness and serum inflammatory cytokines were analyzed in 58 taxi drivers with and without co-morbidity. The results demonstrated that considering only taxi drivers without co-morbidities, 15% presented carotid intima-media thickness above reference values. For the first time it has been demonstrated that urinary 1-hydroxypyrene levels were associated with carotid intima-media thickness and with serum homocysteine levels. The multiple linear regression analysis showed that several factors may contribute to the increased carotid intima-media thickness, among which age, interleukin-6, fibrinogen and exposure to PAHs stand out. In summary, our results suggest that chronic occupational exposure to atmospheric pollution could be an additional contributor to the atherogenesis process, leading to impaired vascular health. Moreover, carotid intima-media thickness, serum homocysteine levels, fibrinogen and the total cholesterol/HDL-c ratio could be suggested as preventive measures to monitor drivers' health., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Occupational exposure to organic solvents present in paints is responsible for an increased production of reactive species, thus enabling the development of several diseases. Besides, both exo- and endogenous antioxidant defense systems are necessary to avoid oxidative tissue damage. This study investigated possible protective effects of the exo- and endogenous antioxidants on oxidative damage in painters occupationally exposed to organic solvents (n = 42) and controls (n = 28). Retinol, lycopene and β-carotene were significantly lower in the exposed group. Despite the fact that blood toluene was below the biological exposure limits, malondialdehyde levels and antioxidant enzyme activities were increased, whereas reduced glutathione levels were decreased in painters, compared to nonexposed subjects. Moreover, multivariate regression models showed that reduced glutathione and carotenoids (mainly β-carotene) have the major influence on lipid peroxidation (LPO). The present work suggests that the exogenous antioxidants, such as carotenoids, could protect occupationally exposed subjects to xenobiotics from LPO.

Exposure to environmental pollutants has been recognised as a risk factor for cardiovascular events. 1-hydroxypyrene (1-OHP) is a biomarker of exposure to polycyclic aromatic hydrocarbons (PAHs) from traffic-related air pollution. Experimental studies indicate that PAH exposure could be associated with inflammation and atherogenesis. Thus, the purpose of this study was to evaluate whether the biomarker of PAH exposure is associated with biomarkers of inflammation and oxidative stress and if these effects modulate the risk of developing cardiovascular diseases in workers exposed to air pollution. This study included 60 subjects, comprising 39 taxi drivers and 21 non-occupationally exposed persons. Environmental PM2.5 and benzo[a]pyrene (BaP) levels, in addition to biomarkers of exposure and oxidative damage, were determined. Inflammatory cytokines (IL-1β, IL-6, IL-10, TNF-α, IFN-γ and hs-CRP) and serum levels of oxidised LDL (ox-LDL), auto-antibodies (ox-LDL-Ab) and homocysteine (Hcy) were also evaluated. PM2.5 and BaP exhibited averages of 12.4±6.9 μg m(-3) and 1.0±0.6 ng m(-3), respectively. Urinary 1-OHP levels were increased in taxi drivers compared to the non-occupationally exposed subjects (p<0.05) and were positively correlated with pro-inflammatory cytokines and negatively correlated with antioxidants. Furthermore, taxi drivers had elevated pro-inflammatory cytokines, biomarkers of oxidative damage, and ox-LDL, ox-LDL-Ab and Hcy levels, although antioxidant enzymes were decreased compared to the non-occupationally exposed subjects (p<0.05). In summary, our findings indicate that taxi drivers showed major exposure to pollutants, such as PAHs, in relation to non-occupationally exposed subjects. This finding was associated with higher inflammatory biomarkers and Hcy, which represent important predictors for cardiovascular events. These data suggest a contribution of PAHs to cardiovascular diseases upon occupational exposure., (© 2013.)

Several diseases and xenobiotics are known to generate reactive species that may trigger oxidative stress when not properly scavenged by the antioxidant defenses and result in tissue damage. We investigated lipid peroxidation (LPO) as a possible mechanism for tissue damage in some pathologies, in the normal aging process, and in subjects exposed to organic solvents. Plasmatic malondialdehyde (MDA) was quantified by high-performance liquid chromatography with visible wavelength detection in 239 subjects and divided into the following: acute myocardium infarction (AMI), diabetes without complications (D) and hemodialysis (HD) patients; into healthy children, adults, and elderly, all nonexposed to xenobiotics; and into painters occupationally exposed to organic solvents (P). Troponin, glycated hemoglobin, and transminases [aspartate aminotransferase (AST) and alanine aminotransferase] were analyzed. An increase in LPO was observed in AMI, D, HD, and P groups, when compared to healthy adults. No correlation between MDA and age was found. Further, we found positive correlations between MDA versus troponin (r = 0.47), MDA versus HbA1c (r = 0.56), and MDA versus AST (r = 0.41) in AMI, diabetics, and painters, respectively. This work has demonstrated increased lipid and protein damages in myocardium and blood, along with an alteration of hepatic transaminase activities and induction of LPO, suggesting that MDA levels are important to evaluate the extent of tissue alterations and development of acute and chronic conditions.

We evaluated genotoxic effects of exposure to low levels of benzene, a class I human carcinogen, among gasoline station attendants (GSA). Oxidative stress and the protective effects of antioxidants on DNA damage were also analyzed. Although exposures were below ACGIH (American Conference of Governmental Industrial Hygienists) limits, the GSA group presented higher DNA damage indices and micronucleus frequencies, increased oxidative protein damage, and decreased antioxidant capacity relative to the control group. Duration of benzene exposure was correlated with DNA and protein damage. The biomarkers evaluated in this work may provide early signals of damage in subjects occupationally exposed to benzene., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Oxidative stress has been shown to be involved in lead and cadmium toxicity. We recently showed that the activity of the antioxidant enzyme thioredoxin reductase (TrxR) is increased in the kidneys of lead-exposed rats. The present study evaluated the blood cadmium and blood lead levels (BLLs) and their relationship with hematological and oxidative stress parameters, including blood TrxR activity in 50 painters, 23 battery workers and 36 control subjects. Erythrocyte δ-aminolevulinate dehydratase (δ-ALA-D) activity and its reactivation index were measured as biomarkers of lead effects. BLLs increased in painters, but were even higher in the battery workers group. In turn, blood cadmium levels increased only in the painters group, whose levels were higher than the recommended limit. δ-ALA-D activity was inhibited only in battery workers, whereas the δ-ALA-D reactivation index increased in both exposed groups; both parameters were correlated to BLLs (r = -0.59 and 0.84, P < 0.05), whereas the reactivation index was also correlated to blood cadmium levels (r = 0.27, P < 0.05). The changes in oxidative stress and hematological parameters were distinctively associated with either BLLs or blood cadmium levels, except glutathione-S-transferase activity, which was correlated with both lead (r = 0.34) and cadmium (r = 0.47; P < 0.05). However, TrxR activity did not correlate with any of the metals evaluated. In conclusion, blood TrxR activity does not seem to be a good parameter to evaluate oxidative stress in lead- and cadmium-exposed populations. However, lead-associated changes in biochemical and hematological parameters at low BLLs underlie the necessity of re-evaluating the recommended health-based limits in occupational exposure to this metal., (Copyright © 2011 John Wiley & Sons, Ltd.)

Trichomonas vaginalis is a parasite of the human urogenital tract that causes trichomonosis, the most prevalent non-viral sexually transmitted disease. Ectonucleoside triphosphate diphosphohydrolase (NTPDase) family members, which hydrolyse extracellular ATP and ADP and ecto-5'-nucleotidase, which hydrolyses AMP, have been characterised in T. vaginalis. For trichomonad culture, the growth medium is supplemented with 10% serum, which is an important source of nutrients, such as adenosine. Here, we investigated the ATP metabolism of T. vaginalis trophozoites from long-term cultures and clinical isolates under limited bovine serum conditions (1% serum). The specific enzymatic activities were expressed as nmol inorganic phosphate (Pi) released/min/mg protein, the gene expression patterns were determined by reverse transcriptase-polymerase chain reaction, the extracellular adenine nucleotide hydrolysis was analysed by high performance liquid chromatography and the cell cycle analysis was assessed by flow cytometry. Serum limitation led to the profound activation of NTPDase and ecto-5'-nucleotidase activities. Furthermore, the levels of NTPDase A and B transcripts increased and extracellular ATP metabolism was activated, which led to enhanced ATP hydrolysis and the formation of ADP and AMP. Moreover, the cell cycle was arrested at the G0/G1 stage, which suggested adenosine uptake. Our data suggest that under conditions of serum limitation, NTPDase and ecto-5'-nucleotidase play a role in providing the adenosine required for T. vaginalis growth and that this process contributes to the establishment of parasitism.

Aim: Hyperglycemia in diabetes mellitus (DM) may be one of the most important factors responsible for the development of oxidative stress, which promotes the main complications in DM patients. Therefore, this study evaluated if the hyperglycemia could be related to oxidative stress biomarkers, lipid profile, and renal function in type 2 diabetes patients without clinic complications., Methods: Plasmatic malondialdehyde (MDA), serum protein carbonyl (PCO), serum creatinine levels, microalbuminuria, glycated hemoglobin, and lipid profile were analyzed in 37 type 2 diabetic patients and 25 subjects with no diabetes., Results: Serum creatinine levels were within the reference values, but microalbuminuria presented increased levels in all the patients compared with controls (P < 0.05) and above of the reference values. The MDA, PCO, low-density lipoprotein, and triglyceride levels showed positive correlation with microalbuminuria levels. Moreover, glycated hemoglobin presented positive correlation with MDA, PCO, and microalbuminuria levels., Conclusions: The hyperglycemia could be responsible for the increase of the microalbuminuria levels and for the oxidation process in lipids and proteins in DM patients. Therefore, we suggested that the microvascular lesion is a direct consequence from hyperglycemia and an indirect one from the increased oxidative stress. Malondialdehyde and protein carbonyl levels could be suggested as additional biochemical evaluation to verify tissue damage in type 2 DM patients.

Extracts of Citrus aurantium L. (Rutaceae) unripe fruits have gained popularity for the treatment of obesity. Due to the wide use of C. aurantium/p-synephrine-containing products, this research was undertaken to evaluate its subchronic toxicity in mice and their actions in oxidative stress biomarkers. Groups of 9-10 mice received for 28 consecutive days a commercial C. aurantium dried extract (containing 7.5% p-synephrine) 400, 2000 or 4000 mg/kg and p-synephrine 30 or 300 mg/kg by oral gavage. There was a reduction in body weight gain of animals treated with both doses of p-synephrine. Organs relative weight, biochemical and hematological parameters were not altered in all treated mice. There was an increase in reduced glutathione (GSH) concentration in groups treated with C. aurantium 4000 mg/kg and p-synephrine 30 and 300 mg/kg. In glutathione peroxidase (GPx), there were an inhibition of the activity in C. aurantium 400 and 2000 mg/kg and p-synephrine 30 and 300 mg/kg treated animals, respectively, and was no alteration in malondialdehyde (MDA) levels. Thus, the results indicate a low subchronic toxicity of the tested materials in mice and a possible alteration in the oxidative metabolism. However, further tests are required to better elucidate the effects of these compounds in the antioxidant system.

Reactive oxygen species are implicated as mediators of tissue damage in the acute renal failure induced by inorganic mercury. Astaxanthin (ASX), a carotenoid with potent antioxidant properties, exists naturally in various plants, algae, and seafoods. This paper evaluated the ability of ASX to prevent HgCl(2) nephrotoxicity. Rats were injected with HgCl(2) (0 or 5 mg/kg b.w., sc) 6h after ASX had been administered (0, 10, 25, or 50mg/kg, by gavage) and were killed 12h after HgCl(2) exposure. Although ASX prevented the increase of lipid and protein oxidation and attenuated histopathological changes caused by HgCl(2) in kidney, it did not prevent creatinine increase in plasma and delta-aminolevulinic acid dehydratase inhibition induced by HgCl(2). Glutathione peroxidase and catalase activities were enhanced, while superoxide dismutase activity was depressed in HgCl(2)-treated rats when compared to control and these effects were prevented by ASX. Our results indicate that ASX could have a beneficial role against HgCl(2) toxicity by preventing lipid and protein oxidation, changes in the activity of antioxidant enzymes and histopathological changes.

Background: Malondialdehyde (MDA) is one of the better-known secondary products of lipid peroxidation, and it is widely used as an indicator of cellular injury. The employment of the thiobarbituric acid reactive substances (TBARS) technique to measure MDA has received criticism over the years because of its lack of specificity. Thus, a specific and reliable method for MDA determination in plasma by high performance liquid chromatographic (HPLC)-VIS was validated; alkaline hydrolysis, n-butanol extraction steps and MDA stability were established., Methods: The plasma underwent alkaline hydrolysis, acid deproteinization, derivatization with TBA and n-butanol extraction. After this, MDA was determined at 532 nm by HPLC-VIS. The method was applied to 65-year-old subjects from a retirement home., Results: The assay was linear from 0.28 to 6.6 microM. The reproducibility of intra-run was obtained with CV%<4% and the inter run with CV%<11%. The accuracy (bias) ranged from 2 to -4.1%, and the recovery was greater than 95%. The limit of detection (LOD) and limit of quantification (LOQ) were 0.05 and 0.17 microM, respectively. For the stability test, every sample was stored at -20 degrees C. The plasma MDA was not stable when stored after the alkaline hydrolysis step, remained stable for 30 days after TBA derivatization storage and was stable for 3 days when stored after n-butanol extraction. The elderly subjects had MDA plasma levels of 4.45+/-0.81 microM for women and 4.60+/-0.95 microM for men., Conclusion: The method is reproducible, accurate, stable, sensitive, and can be used in the routines in clinical laboratories. Besides, this technique presents advantages such as the complete release of protein bound MDA with the alkaline hydrolysis step, the removal of interferents with n-butanol extraction, mobile phase without phosphate buffer and rapid analytical processes and run times.