Vitaminas e minerais com propriedades antioxidantes e risco cardiometabólico: controvérsias e perspectivas

Zn and Se abrogate heavy metal mixture induced ovarian and thyroid oxido-inflammatory effects mediated by activation of NRF2-HMOX-1 in female albino rats

The thyroid is vital for the proper functioning of the female reproductive system since it regulates the metabolism and development of ovary. This is an evaluation of the essential trace elements ETE on the heavy metals mixture HMM mediated oxido-inflammatory effects in the ovary and thyroid of female albino rats. Eight groups (5 female rats /group) were treated as follows for 60 days: Group 1: Deionized water only; Group 2: (Pb, Hg, Mn and Al); Group 3: HMM + ZnCl₂, 0.80 mg/kg; Group 4: HMM + Na₂SeO₃, 1.50 mg/kg; Group 5: HMM + ZnCl₂, 0.80 mg/kg and Na₂SeO₃, 1.50 mg/kg combined. On day 60 animals were euthanized, ovary and thyroid were harvested and used for, MDA, NO, antioxidants, TNF-α, IL-6, HMOX-1, Caspase-3, NF-KB, NRF2, HM and histopathology. There was significant bioaccumulation of Pb, Al, Hg and MN; elevated IL-6 and TNF-α, MDA and NO, caspase-3 and NRF2, NFKB and HMOX-1 with significant decrease in antioxidants in the HMM only group in comparison to the control. Co-treatment with ETE reversed most of these effects. ETE may ameliorate HMM -induced ovarian and thyrotoxicity in female albino rats by blunting oxido-inflammatory activities.

Increased pressure sore risk has a worse diagnosis in hospitalized Stroke patients / Maior risco de lesão por pressão tem pior prognóstico na hospitalização de pacientes com Acidente Vascular Cerebral

Objetivo: associar o risco de lesão por pressão com a gravidade de pacientes hospitalizados com Acidente Vascular Cerebral. Método: estudo transversal, 64 pacientes hospitalizados com Acidente Vascular Cerebral. Foram coletados dados sociodemográficos em prontuário, sendo realizada avaliação antropométrica, risco de lesão por pressão pela Escala de Braden e vitamina C sérica. Resultados: amostra predominantemente de idosos com Acidente Vascular Cerebral isquêmico, 48,4% apresentaram alto risco de desenvolver lesão por pressão. Pacientes com maior risco de lesão por pressão tiveram maior mortalidade (p < 0,001), leucocitose (p = 0,028) e linfopenia (p <0,001) quando comparados com pacientes com menor risco. No entanto, os níveis de vitamina C sérica não diferiram estatisticamente entre o risco de lesão. Sobre o estado nutricional não houve diferenças significativas entre o risco de lesão por pressão. Conclusão: conclui-se que pacientes com alto risco de desenvolver lesão por pressão apresentam leucocitose, linfopenia e maior risco de mortalidade./p>

Protective Effects of Selenium and Zinc Against Nickel Chloride-Induced Hormonal Changes and Oxidative Damage in Thyroid of Pregnant Rats

Nickel chloride (NiCl₂) is a heavy metal that may affect the function of the thyroid. Selenium (Se) and zinc (Zn) are essential trace elements involved in thyroid hormone metabolism. However, little is reported about thyrotoxicity during gestation. The current study aimed to investigate the protective effects of selenium and zinc against NiCl₂-induced thyrotoxicity in pregnant Wistar rats. Female rats were treated subcutaneously (s.c.) on the 3rd day of pregnancy, with NaCl 0.9% and served as control, NiCl₂ (100 mg/kg body weight (BW)) alone, or in association with Se (0.3 mg/kg, s.c.), ZnCl₂ (20 mg/kg, s.c.), or both of them simultaneously. Oxidative stress parameters, thyroid biomarkers, and histopathological examination were evaluated. Results showed that NiCl₂ exposure caused a significant decrease in maternal body weight and an increase in absolute and relative thyroid weight compared to the controls. NiCl₂ administration also led to decreased plasma triiodothyronine (T3) and thyroxine (T4) with a concomitant significant increase in thyroid-stimulating hormone (TSH) levels when compared to that of control. In addition, an overall pro-oxidant effect was associated with a decrease in the reduced glutathione (GSH) and nonprotein thiol (NPSH) contents and the enzymatic activity of glutathione peroxidase (GPx) and superoxide dismutase (SOD), and an increase in malondialdehyde (MDA). These biochemical disturbances were confirmed by histological changes. However, the co-treatment of Se and/or ZnCl₂ attenuates NiCl₂-induced changes. Our findings suggested that Se and ZnCl₂ ameliorated NiCl₂-induced thyrotoxicity in pregnant Wistar rats by exhibiting antioxidant effects.

Nutritional supplements in the management of oral mucositis in patients with head and neck cancer: Narrative literary review

BACKGROUND AND AIMS

Oral mucositis is the most common side effect in response to anticancer therapies in the head and neck region. It has a debilitating potential for the health of affected individuals, negatively interfering with nutritional status and quality of life. Due to the great complexity of its pathogenicity, different forms of interventions for prevention and treatment are being studied, including nutritional supplements with vitamin E, zinc and glutamine. This study aimed to review the literature on the influence of nutrients, in supplement form, for prevention and/or treatment of mucositis in patients with head and neck cancer.

METHODS

A survey of studies related to the definition, treatment and prevention of mucositis with nutrients was carried out between January 2018 and July 2019, using the Pubmed, Cochrane Library and Scielo databases. In the end, 61 relevant scientific publications were selected between the years 2004 and 2019.

RESULTS

Nutrients such as vitamin E, glutamine and zinc are forms of supplementation that have positive effects on the manifestation and severity of oral mucositis due to their antioxidant and immunomodulatory properties. However, some studies reveal that antioxidant properties may reduce the effectiveness of antineoplastic therapy.

CONCLUSIONS

This study suggests the effectiveness of vitamin E, zinc and glutamine in preventing and treating oral mucositis. However, the importance of new clinical researches to clarify possible doubts is highlighted, as well as the creation of a protocol that includes the dose, route and time of administration, for greater safety in use.

[Analysis of the biochemical, anthropometric profile, and of antioxidant micronutrient ingestion in patients with resistant arterial hypertension]

Introduction

Introduction: resistant arterial hypertension (HAR) is associated with a high risk for cardiovascular events due to oxidative stress. Research has shown the beneficial effects of dietary antioxidants on cardiovascular health. Objective: to analyze and correlate the biochemical, anthropometric profile and intake of antioxidant micronutrients of patients with HAR. Material and methods: the patients underwent a biochemical assessment, and an anthropometric assessment to calculate body mass index (IMC), waist circumference (PCI), hip circumference (PCA), waist-to-hip ratio (ICC), and micronutrient intake assessment: vitamin A, vitamin C, vitamin E, selenium and zinc, estimated by a semi-quantitative food frequency questionnaire and 24-hour recall. The statistical analysis was performed using the SPSS Statistics 20 software. A p-value < 0.05 was considered significant. Results: sixty individuals with HAR were studied, with a mean age of 62.83 ± 10.73 years. Mean IMC was 31.01 ± 5.60 kg/m², PCI, 98.12 ± 15.04 cm, PCA, 110.55 ± 13.16 cm, and ICC, 0.879 ± 0.084. Regarding the biochemical profile, mean total colesterol was 187.65 ± 48.29 mg/dL, triglycerides, 136.38 ± 99.91 mg/dL; HDL-col, 49.00 ± 10.99 mg/dL; LDL-col, 112.01 ± 41.89 mg/dL; glucose, 105.37 ± 14.81 mg/dL, and glycated hemoglobin, 6.29 ± 1.76 %. The average daily intake of antioxidants was: vitamin A, 241.47 ± 191.87 µg/d; vitamin C, 147.02 ± 192.94 mg/d; vitamin E, 1.99 ± 1.82 mg/d; selenium, 36.80 ± 34.56 µg/d, and zinc, 99.91 ± 6.64 mg/d, where 91.38 %, 46.55 %, 93.10 %, 67.24 %, and 46.55 % of the sample were below the recommended intakes, respectively. Conclusion: inadequate antioxidant intake was observed in these patients with HAR, with a high prevalence of obesity, especially visceral adiposity and alterations in lipid profile, conditions that require a greater usage of these micronutrients. We suggest there is a need for dietary planning for these patients to improve their quality of life and their response to antihypertensive treatment.

Oxidative Stress Mediates Anxiety-Like Behavior Induced by High Caffeine Intake in Zebrafish: Protective Effect of Alpha-Tocopherol

Anxiety is a common symptom associated with high caffeine intake. Although the neurochemical mechanisms of caffeine-induced anxiety remain unclear, there are some evidences suggesting participation of oxidative stress. Based on these evidences, the current study is aimed at evaluating the possible protective effect of alpha-tocopherol (TPH) against anxiety-like behavior induced by caffeine (CAF) in zebrafish. Adult animals were treated with CAF (100 mg/kg) or TPH (1 mg/kg)+CAF before behavioral and biochemical evaluations. Oxidative stress in the zebrafish brain was evaluated by a lipid peroxidation assay, and anxiety-like behavior was monitored using light/dark preference and novel tank diving test. Caffeine treatment evoked significant elevation of brain MDA levels in the zebrafish brain, and TPH treatment prevented this increase. Caffeine treatment also induced anxiety-like behavior, while this effect was not observed in the TPH+CAF group. Taken together, the current study suggests that TPH treatment is able to inhibit oxidative stress and anxiety-like behavior evoked by caffeine.

Impact of colibacillosis on production in laying hens associated with interference of the phosphotransfer network and oxidative stress

The objective of this study was to evaluate the productive impact of colibacillosis on laying hens and to investigate whether energetic metabolism and oxidative stress were involved in the pathogenesis of the disease. An experimental shed containing 270 laying hens of the Hy-Line lineage (32 weeks old) presented approximately 40% daily laying, and many birds presented with diarrhea and apathy followed by death. Necropsy revealed macroscopic lesions compatible with colibacillosis and infectious agent Escherichia coli was isolated from fecal samples of all birds in the infected group, as well as from tissue (ovary, liver and peritoneum). Sixteen chickens were selected for this study, divided into two groups: Control (animals without clinical alterations) and infected (with diarrhea and apathetic). E. coli isolates were subjected to the antimicrobial susceptibility testing according to the methodology approved by CLSI, 2018. This testing showed sensitivity to gentamicin, amoxicillin, norfloxacin and colistin. It was then determined that laying hens would be treated with norfloxacin (15 mg/kg) diluted in water offered at will to the birds for three days. Blood collections were performed via brachial vein after the diagnosis of E. coli (before starting treatment) and seven days after treatment. Three debilitated chickens died on the second day after initiating therapy. Before treatment, birds with clinical signs had higher levels of lipoperoxidation (LPO) and activities of antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) than in the control group (asymptomatic animals). After treatment, LPO levels remained higher in birds that had clinical disease (infected group), whereas the activity of SOD and GPx enzymes did not differ between groups. Activity levels of creatine kinase (CK) and pyruvate kinase (PK) were higher in the group of chickens with clinical disease before treatment. Post-treatment, no differences were observed between groups in terms of CK; however, PK activity remained high in these animals. In the hens that died, there were lesions characteristic of avian colibacillosis, with ovary involvement, explaining the low laying activity of the birds at their peak of production. For 10 days after starting treatment, the percentage of laying increased to 90%. Therefore, we conclude that colibacillosis interferes with the phosphotransfer network by stimulating ATP production, in addition to causing oxidative stress of the birds during laying, that negatively affects health and productive efficiency.

Mechanisms underlying nickel nanoparticle induced reproductive toxicity and chemo-protective effects of vitamin C in male rats

The purpose of this research is to go a step further study on the reproductive toxicities and the underlying mechanisms induced by nickel nanoparticles (NiNPs), and the possible protective action of vitamin C. Animal experiment was designed according to the one-generation reproductive toxicity standard, and rats were exposed to NiNPs through gavage. Ultrastructural, reactive oxygen species (ROS), oxidant and antioxidant enzymes, and cell apoptosis-related factors in the testicular tissue were analyzed. In contrast with the control group, the activity of surperoxide dismutase (SOD), catalase (CAT) and gonad-stimulating hormone (GSH) was reduced, while the content of nitric oxide (NO), malondialdehyde (MDA) and ROS was increased in the NiNPs treated animals. As the doses of NiNPs increase, the mRNA of apoptotic related factor Caspase-9, Caspase-8 and Caspase-3 showed an obviously upregulation. Protein expression of Bcl-2-associated X Protein (Bax) and apoptosis inducing factor (AIF) was significantly unregulated. After addition of antioxidants-vitamin C, the toxicity was reduced. Injured testicular tissue indicated that NiNPs exposure could damage the reproductive system. Our results suggest that NiNPs induce significant reproductive toxicities. The cellular apoptosis might be induced by caspase family proteinases, but the regulator factor (factor associated suicide (Fas), B-cell lymphoma-2 (Bcl-2), Bax, BH3-interacting domain death agonist (Bid) and AIF protein) might not be involved in this process. Thus, the mechanism of reproductive toxicity of NiNPs on rat testes involves in the induction of oxidative stress, which further results in cell apoptosis. Antioxidants-vitamin C shows a significant inhibition on the reproductive toxicities induced by NiNPs.

Perfil nutricional e benefícios do azeite de abacate (Persea americana ): uma revisão integrativa

Resumo O objetivo do presente estudo foi realizar uma revisão integrativa sobre a qualidade do perfil lipídico e dos compostos bioativos presentes no azeite de abacate, bem como sobre os seus potenciais benefícios para a saúde humana. Foram identificados trabalhos publicados nas bases de dados Scopus, PubMed, Lilacs, SciELO e Web of Science, além de Biblioteca Digital de Teses e Dissertações. A pesquisa encontrou dados referentes ao perfil lipídico e ao teor de substâncias bioativas presentes no azeite de abacate extraído das variedades Margarida, Quintal, Fortuna, Ouro Verde, Hass e Fuerte. O azeite de abacate caracteriza-se por apresentar, em média, teores elevados de ácidos graxos monoinsaturados (60%), teor intermediário de ácidos graxos saturados (24%) e baixo teor de ácidos graxos poli-insaturados (16%). O ácido graxo oleico (ômega-9) é o de maior concentração (aproximadamente 55%). Os principais esteróis, tocoferóis e carotenoides encontrados foram β-sitosterol, α-tocoferol e luteína, respectivamente. O azeite de abacate possui propriedades físico-químicas semelhantes às do azeite de oliva. Em modelos animais, é capaz de prevenir a disfunção mitocondrial cerebral e hepática induzida pelo diabetes, associado à diminuição de estresse oxidativo, LDL-c e peroxidação lipídica. Seus benefícios são atribuídos principalmente às concentrações de ácido oleico, por sua atividade cardioprotetora, ao β-sitosterol, por sua propriedade anti-inflamatória, e ao α-tocoferol e à luteína, pela propriedade antioxidante. Assim, o azeite de abacate se destaca pelo teor elevado de ácidos graxos monoinsaturados e de compostos bioativos, como tocoferóis, carotenoides e fitoesteróis. Análises em modelos animais, aliadas às análises de qualidade e segurança, atestam os benefícios e a possibilidade de introdução do referido azeite para uso comestível, substituindo óleos de qualidade inferior e criando nova alternativa gastronômica ao consumidor.

Action of cholecalciferol and alpha-tocopherol on Staphylococcus aureus efflux pumps

Alpha-tocopherol is one the most abundant and biologically active isoforms of vitamin E. This compound is a potent antioxidant and one of most studied isoforms of vitamin E. Vitamin D3 (cholecalciferol) is an important nutrient for calcium homeostasis and bone health, that has also been recognized as a potent modulator of the immune response. Methicillin-resistant Staphylococcus aureus (MRSA) is the most important causative agent of both nosocomial and community-acquired infections. The aim of this study was to evaluate the inhibitory effect of alpha-tocopherol and cholecalciferol on both S. aureus and multidrug resistant S. aureus efflux pumps. The RN4220 strain has the plasmid pUL5054 that is the carrier of gene that encodes the macrolide resistance protein (an efflux pump) MsrA; the IS-58 strain possesses the TetK tetracycline efflux protein in its genome and the 1199B strain resists to hydrophilic fluoroquinolones via a NorA-mediated mechanism. The antibacterial activity was evaluated by determining the Minimal Inhibitory Concentration (MIC) and a possible inhibition of efflux pumps was associated to a reduction of the MIC. In this work we observed that in the presence of the treatments there was a decrease in the MIC for the RN4220 and IS-58 strains, suggesting that the substances presented an inhibitory effect on the efflux pumps of these strains. Significant efforts have been done to identify efflux pump inhibitors (EPIs) from natural sources and, therefore, the antibacterial properties of cholecalciferol and alpha-tocopherol might be attributed to a direct effect on the bacterial cell depending on their amphipathic structure.

Evaluation of p-cymene, a natural antioxidant

CONTEXT

Several studies have demonstrated that essential oils and their major components have antioxidant activity. p-Cymene is a monoterpene and a major constituent of essential oils of various species of plants.

OBJECTIVE

This paper evaluated the antioxidant potential of p-cymene in the hippocampus of mice by determining the levels of thiobarbituric acid reactive substances (TBARS), nitrite content, and activity of catalase (CAT) and superoxide dismutase (SOD).

MATERIALS AND METHODS

Swiss mice were intraperitoneally treated with 0.05% Tween 80 dissolved in 0.9% saline solution, ascorbic acid 250 mg/kg, and p-cymene at doses of 50, 100, and 150 mg/kg, respectively. After treatment, all groups were observed for 24 h, afterwards, the groups were euthanized for removal of the brain and dissection of the hippocampus.

RESULTS

The results of treatment with p-cymene were a significant decrease in lipid peroxidation and nitrite content at a dose of CYM 50: 65.54%, CYM 100: 73.29%, CYM 150: 89.83%, and CYM 50: 71.21%; CYM 100: 68.61% and CYM 150:67%, respectively, when compared with the control group. The results showed that at all tested doses, p-cymene produces an increase in SOD and catalase activity significantly at a dose of CYM 50: 22.7%, CYM 100: 33.9%, CYM 150: 63.1%, and CYM 50: 119.25%, CYM 100: 151.83% and CYM 150: 182.70%, respectively, when compared with the vehicle-treated group.

DISCUSSION AND CONCLUSION

The result of this study shows that p-cymene has an antioxidant potential in vivo and may act as a neuroprotective agent in the brain. This compound may present a new strategy in the development of treatment for many diseases in which oxidative stress plays an important pathophysiological role.

Enhancement of the antibiotic activity of aminoglycosides by alpha-tocopherol and other cholesterol derivates

Alpha-tocopherol, one of the most abundant isoforms of vitamin E, is a biologically active liposoluble vitamin and potent antioxidant. It occurs naturally in foods of plant and animal origin. Because of its lipophilic character, it can cause perturbations in the bacterial cell membrane, resulting in damage to components essential for the integrity of the membrane, thereby allowing an increase in permeability. This is the first report of the modulatory effect of alpha-tocopherol in multiresistant bacteria. We evaluated alpha-tocopherol against multiresistant strains of Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli, and determined if there was any similarity with the mechanism of modulatory action of cholesterol and ergosterol. When combined with aminoglycosides in a microdilution broth assay, alpha-tocopherol possibly acted through a lipophilic action on the cell envelope, modulating more effectively P. aeruginosa and E. coli, when compared with S. aureus.

Assessment of antioxidants status and superoxide dismutase activity in HIV-infected children

Objective

This study aims to assess the nutritional status of selenium, copper and zinc; and also the erythrocyte superoxide dismutase activity of HIV-infected children compared to a control group.

Methods

A cross-sectional study was carried out with prepubertal HIV-infected children (n = 51) and their healthy siblings (n = 32). All biochemical measurements including plasma selenium, serum copper levels, serum and erythrocyte zinc levels and erythrocyte superoxide dismutase activity were evaluated according to dietary, clinical and biochemical parameters.

Results

Compared to the control group, the HIV-infected children had lower z-score values for height-for-age (p = 0.0006), higher prevalence of stunting (11.8%) (p = 0.047), lower selenium levels (p = 0.0006) and higher copper levels (p = 0.019). No difference was found concerning superoxide dismutase activity (p > 0.05). The HIV-infected group presented a higher proportion (45.1%) of children with zinc intakes below the estimated average requirement (p = 0.014); however, no association with zinc biochemical parameters was found.

Conclusion

HIV-infected children have an inadequate selenium and copper nutritional status, which could influence the progression to AIDS. An adequate micronutrient status could improve the clinical conditions in these patients and minimize free radical production and cellular oxidative stress.

Alpha-tocopherol concentration in serum and colostrum of mothers with gestational diabetes mellitus

OBJECTIVE

To evaluate and compare the levels of α-tocopherol in colostrum and in the serum of healthy and diabetic mothers.

METHODS

This cross-sectional study enrolled 51 volunteer mothers, 20 with the diagnosis of gestational diabetes mellitus and 31 without associated diseases. Serum and colostrum samples were collected in fasting in the immediate postpartum period and α-tocopherol was analyzed by high performance liquid chromatography (HPLC). In order to define the nutritional status of vitamin E, the cutoff point for the serum (697.7µg/dL) was adopted. Student's t-test for independent variables compared the average concentrations of α-tocopherol in the serum and in the colostrum between control and gestational diabetes mellitus groups. Pearson's correlation was used to assess the relationship between the concentration of α-tocopherol in serum and colostrum for both groups. Differences were considered significant when p<0.05.

RESULTS

The α-tocopherol concentration in colostrum was 1,483.1±533.8µg/dL for Control Group and 1,368.8±681.8µg/dL for diabetic women, without differences between groups (p=0.50). However, α-tocopherol concentration in the serum was 1,059.5±372.7µg/dL in the Control Group and 1,391.4±531.5µg/dL in the diabetic one (p<0.01). No correlation was found between the concentration of α-tocopherol in the serum and in the colostrum for control and diabetic groups.

CONCLUSIONS

The groups had adequate nutritional status of vitamin E. Gestational diabetes was not associated with changes in α-tocopherol concentration in colostrum.

Prediction of disease-related interactions between microRNAs and environmental factors based on a semi-supervised classifier

Accumulated evidence has shown that microRNAs (miRNAs) can functionally interact with a number of environmental factors (EFs) and their interactions critically affect phenotypes and diseases. Therefore, in-silico inference of disease-related miRNA-EF interactions is becoming crucial not only for the understanding of the mechanisms by which miRNAs and EFs contribute to disease, but also for disease diagnosis, treatment, and prognosis. In this paper, we analyzed the human miRNA-EF interaction data and revealed that miRNAs (EFs) with similar functions tend to interact with similar EFs (miRNAs) in the context of a given disease, which suggests a potential way to expand the current relation space of miRNAs, EFs, and diseases. Based on this observation, we further proposed a semi-supervised classifier based method (miREFScan) to predict novel disease-related interactions between miRNAs and EFs. As a result, the leave-one-out cross validation has shown that miREFScan obtained an AUC of 0.9564, indicating that miREFScan has a reliable performance. Moreover, we applied miREFScan to predict acute promyelocytic leukemia-related miRNA-EF interactions. The result shows that forty-nine of the top 1% predictions have been confirmed by experimental literature. In addition, using miREFScan we predicted and publicly released novel miRNA-EF interactions for 97 human diseases. Finally, we believe that miREFScan would be a useful bioinformatic resource for the research about the relationships among miRNAs, EFs, and human diseases.

Obesity and metabolic syndrome: potential benefit from specific nutritional components

The prevalence of metabolic syndrome (MetS) manifestations is rapidly increasing worldwide, and is becoming an important health problem. Actually, MetS includes a combination of clinical complications such as obesity (central adiposity), insulin resistance, glucose intolerance, dyslipidemia, non-alcoholic fatty liver disease and hypertension. All these alterations predispose individuals to type 2 diabetes and cardiovascular disease inducing earlier mortality rates among people. In general terms, it is difficult for patients to follow a standard long-term diet/exercise regime that would improve or alleviate MetS symptoms. Thus, the investigation of food components that may deal with the MetS features is an important field for ameliorate and facilitate MetS dietary-based therapies. Currently antioxidants are of great interest due to the described association between obesity, cardiovascular alterations and oxidative stress. On the other hand, high MUFA and PUFA diets are being also considered due to their potential benefits on hypertension, insulin resistance and triglyceride levels. Mineral composition of the diet is also relevant since high potassium intake may improve hypertension and high calcium consumption may promote lipid oxidation. Thus, although nutritional supplements are at the peak of dietetic therapies, the consumption of some specific foods (legumes, fatty fish, vegetables and fruits, etc) with bioactive components within an energy-restricted diet is a promising approach to manage MetS manifestations. Therefore, the present review focuses on some of the most important food components currently investigated to improve and make easier the nutritional MetS treatment.

Oxidative damage to biological macromolecules in Prague bus drivers and garagemen: impact of air pollution and genetic polymorphisms

DNA integrity was investigated in the lymphocytes of 50 bus drivers, 20 garagemen and 50 controls using the comet assay with excision repair enzymes. In parallel, 8-oxo-7,8-dihydro-2'-deoxyguanosine and 15-F(2t)-isoprostane levels in the urine and protein carbonyl levels in the plasma were assessed as markers of oxidative damage to DNA, lipids and proteins. Exposure to carcinogenic polycyclic aromatic hydrocarbons (cPAHs) and volatile compounds was measured by personal samplers for 48 and 24h, respectively, before the collection of biological specimens. Both exposed groups exhibited a higher levels of DNA instability and oxidative damage to biological macromolecules than the controls. The incidence of oxidized lesions in lymphocyte DNA, but not the urinary levels of 8-oxodG, correlated with exposure to benzene and triglycerides increased this damage. Oxidative damage to lipids and proteins was associated with exposure to cPAHs and the lipid peroxidation levels positively correlated with age and LDL cholesterol, and negatively with vitamin C. The carriers of at least one variant hOGG1 (Cys) allele tended to higher oxidative damage to lymphocyte DNA than those with the wild genotype, while XPD23 (Gln/Gln) homozygotes were more susceptible to the induction of DNA strand breaks. In contrast, GSTM1 null variant seemed to protect DNA integrity.

Study on clinical and biochemical toxicity biomarkers in a zinc-lead mine workers

The aim of this study was to determine oxidative stress status as well as blood lead (Pb) and zinc (Zn) levels and clinical markers in workers of a Zn-Pb mine. A comparative cross-sectional analysis was performed in 67 mine workers who have been in contact with Zn and Pb in comparison to a control group containing 67 healthy subjects with the same age and sex. Lipid peroxidation, superoxide dismutase, catalase, glutathione reductase, myleoperoxidase, DNA damage, total antioxidant capacity, Zn, and Pb levels were measured in blood of workers and controls. Clinical examination was accomplished to record any abnormal sign or symptoms. Comparing with controls, the workers showed higher blood levels of superoxide dismutase, myleoperoxidase, glutathione reductase, lipid peroxidation, Pb, and Zn. Workers showed lower DNA-damage as compared with controls. Workers showed clinical symptoms such as memory impairment, less of concentration, insomnia, headache, claudication, epigasteric, inappetence, agitation, tremor, decreasing of reflection of deep tendon, conduction deafness of ear, and fatigue. The workers had extra normal levels of Pb (0.9-3 microg/dL) and showed oxidative stress. Taken together, the results indicate that exposure to combination of Pb and Zn in mine elevates total antioxidant capacity of body in a reflex to overcome to oxidative stress. Especially, in the present case, it seems that toxic effect of Pb has been greater than positive effects of Zn, but the combination exposure has resulted in not such a critical toxicity situation.