Dual effect of the herbal matcha green tea (Camellia sinensis L. kuntze) supplement in EA.hy926 endothelial cells and Artemia salina.

ETHNOPHARMACOLOGICAL RELEVANCE: Matcha green tea (Camellia sinensis) based-supplements have been widely used since they present a greater content of phenolic compounds than traditional green tea, which is popularly used in the treatment of diabetes. However, there are few studies on the effectiveness and safety of matcha supplements. AIM OF THE STUDY: This work aimed to evaluate the efficacy and safety of this supplement in endothelial cells (EA.hy926) in the hyperglycemic model and in vivo Artemia salina. MATERIALS AND METHODS: To assess the effect of Matcha herbal supplement (MHS), EA. hy926 endothelial cells were treated with 20 µg/mL of MHS for 24 h, in a hyperglycemic medium with 35 mM glucose. After treatment, cells were trypsinized and centrifuged at 4 °C and 47×g for 5 min. The pellet was used to determine the reaction products to thiobarbituric acid and the levels of nitric oxide. Electron transport chain activity and ATP levels were also evaluated. Intracellular pH, apoptosis, and mitochondrial membrane depolarization were evaluated by flow cytometry. MHS chemical characterization was performed by HPLC-UV and total phenolic content analysis. The evaluation of the antioxidant capacity of MHS was performed by 2,2-diphenyl-1-picrylhydrazyl radical scavenger assay. To determine the in vivo acute toxicity of MHS, an A. salina assay was conducted, using 0,2 mL of different concentrations of MHS (10, 50, 100, 250, 500, 750 and 1000 µg/mL). The LD50 values were obtained by interpolation of 50% (y = 50) of the dead individuals in the trend curves. RESULTS: Our data showed that MHS was able to avoid oxidative and nitrosative stress induced by hyperglycemia, demonstrating important antioxidant activity. However, it was observed that MHS reduced up to 90% the activity of the four-electron transport complexes, reducing the ATP production of the endothelial cells. In the toxicity assay performed in Artemia salina, MHS showed mild toxicity (LD50 = 0,4 mg/mL). The major compounds found in MHS were epigallocatechin gallate, epicatechin, rutin, kaempferol, and quercetin. CONCLUSIONS: This data draws attention to the fact that supplements with high content of phenolic compounds, capable of avoiding oxidative and nitrosative stress can have a dual effect and, simultaneously to antioxidant activity, can induce toxicity in different cell types.

Mutual Effects of Free and Nanoencapsulated Phenolic Compounds on Human Microbiota.

Phenolic compounds (PC) have many health benefits such as antioxidant, anticarcinogenic, neuroprotective, and anti-inflammatory activities. All of these activities depend on their chemical structures and their interaction with biological targets in the body. PC occur naturally in polymerized form, linked to glycosides and require metabolic transformation from their ingestion to their absorption. The gut microbiota can transform PC into more easily absorbed metabolites. PC, in turn, have prebiotic and antimicrobial actions on the microbiota. Despite this, their low oral bioavailability still compromises biological performance. Therefore, the use of nanocarriers has been demonstrated to be a useful strategy to improve PC absorption and, consequently, their health effects. Nanotechnology is an excellent alternative able to overcome the limits of oral bioavailability of PC, since it offers protection from degradation during their passage through the gastrointestinal tract. Moreover, nanotechnology is also capable of promoting controlled PC release and modulating the interaction between PC and the microbiota. However, little is known about the impact of nanotechnology on PC effects on the gut microbiota. This review highlights the use of nanotechnology for PC delivery on gut microbiota, focusing on the ability of such formulations to enhance oral bioavailability by applying nanocarriers (polymeric nanoparticles, nanostructured lipid carriers, solid lipid nanoparticles). In addition, the effects of free and nanocarried PC or nanocarriers per se on gut microbiota are also described.

In vivo toxicological evaluation of polymeric nanocapsules after intradermal administration.

Polymeric nanocarriers have shown great promise as delivery systems. An alternative strategy has been to explore new delivery routes, such as intradermal (i.d.), that can be used for vaccines and patch-based drug delivery. Despite their many advantages, there are few toxicity studies, especially in vivo. We report a safety assessment of biodegradable poly(ɛ-caprolactone) lipid-core nanocapsules (LNC) with a mean size of 245±10nm following single and repeated intradermal injections to Wistar rats. Suspensions were prepared by interfacial deposition of polymer. The animals (n=6/group) received a single-dose of saline solution (1.2ml/kg) or LNC (7.2×10(12)LNC/kg), or repeated-doses of two controls, saline solution or Tween 80 (0.9ml/kg), or three different concentrations of LNC (1.8, 3.6, and 5.4×10(12)LNC/kg) for 28 consecutive days. Clinical and physiological signs and mortality were observed. Samples of urine, blood, and tissue were used to perform toxicological evaluation. There were no clinical signs of toxicity or mortality, but there was a slight decrease in the relative body weights in the Tween 80-treated group (p<0.01) after repeated administration. No histopathological alterations were observed in tissues or significant changes in blood and urinary biomarkers for tissue damage. Mild alterations in white blood cells count with increases in granulocytes in the Tween-80 group (p<0.05) were found. Genotoxicity was evaluated through the comet assay, and no statistical difference was observed among the groups. Therefore, we conclude that, under the conditions of these experiments, biodegradable LNC did not present appreciable toxicity after 28 consecutive days of intradermal administration and is promising for its future application in vaccines and patch-based devices for enhancing the delivery of drugs.

Evaluation of genotoxicity and oxidative damage in painters exposed to low levels of toluene.

Toluene is an organic solvent used in numerous processes and products, including industrial paints. Toluene neurotoxicity and reproductive toxicity are well recognized; however, its genotoxicity is still under discussion, and toluene is not classified as a carcinogenic solvent. Using the comet assay and the micronucleus test for detection of possible genotoxic effects of toluene, we monitored industrial painters from Rio Grande do Sul, Brazil. The putative involvement of oxidative stress in genetic damage and the influences of age, smoking, alcohol consumption, and exposure time were also assessed. Although all biomarkers of toluene exposure were below the biological exposure limits, painters presented significantly higher DNA damage (comet assay) than the control group; however, in the micronucleus assay, no significant difference was observed. Painters also showed alterations in hepatic enzymes and albumin levels, as well as oxidative damage, suggesting the involvement of oxidative stress. According to multiple linear regression analysis, blood toluene levels may account for the increased DNA damage in painters. In summary, this study showed that low levels of toluene exposure can cause genetic damage, and this is related to oxidative stress, age, and time of exposure.

Occupational risk assessment of oxidative stress and genotoxicity in workers exposed to paints during a working week.

OBJECTIVES: Paints are complex mixtures of solvents and metals that can induce health damages in workers exposed to them. The aim of the present work was to evaluate possible oxidative and genotoxic effects in workers exposed to paints. MATERIAL AND METHODS: Peripheral blood and buccal cell samples were collected from 33 workers exposed to paints and 29 non-exposed workers (controls) during an ordinary working week (Monday morning and Friday evening). Oxidative markers were assessed using thiobarbituric acid assay, carbonylated proteins, superoxide dismutase and catalase activities. Hippuric acid and delta-aminolevulinic acid were determined as biomarkers of toluene and lead exposure, respectively. Genotoxicity was measured through comet assay and micronucleus (MN) frequencies. RESULTS: The exposed group showed higher hippuric acid and delta-aminolevulinic acid levels (Friday samples) and lower superoxide dismutase activity (Monday samples) in relation to control group. DNA damage index (comet assay) was higher in the exposed group, both in Monday and Friday samples, compared to the control group. No differences were observed in frequency of micronuclei (MN) between the groups, either in lymphocytes or buccal cells. However, the exposed group presented an increase (Monday samples) in nuclear buds frequency in lymphocytes - a marker of gene amplification - as well as an increase in condensed chromatin in the buccal cells (Monday and Friday samples), suggesting induction of apoptosis. Furthermore, a decrease in the nuclear division index (Friday samples) was observed in the exposed group, indicating that paint exposure induces cytostatic effects in lymphocytes. CONCLUSION: The results suggest that individuals exposed to paints have increased levels of DNA damage.

Exposição pré-natal ao etanol: toxicidade, biomarcadores e métodos de detecção / Prenatal exposure to ethanol: toxicity, biomarkers and detection methods

CONTEXTO: A exposição pré-natal ao etanol pode produzir diversos efeitos adversos no desenvolvimento fetal denominados doença espectral do alcoolismo fetal (DEAF). A detecção precoce de exposição ao etanol permite que medidas preventivas sejam tomadas para minimizar os efeitos adversos da exposição. OBJETIVOS: O presente trabalho teve como objetivo revisar os principais efeitos tóxicos do etanol no neonato e os biomarcadores de exposição ao álcool. MÉTODOS: Foi realizada uma pesquisa bibliográfica na base de dados PubMed utilizando os descritores "effects maternal ethanol exposure" e "biomarkers ethanol prenatal exposure", além de referências cruzadas dos artigos selecionados. RESULTADOS: Diversos efeitos adversos no desenvolvimento fetal têm sido descritos, especialmente os prejuízos no sistema nervoso central. Os biomarcadores de exposição mais citados na literatura são os etil ésteres de ácidos graxos (EEAG), etil glicuronídeo (EtG) e etil sulfato (EtS) utilizando mecônio e cabelo como matriz biológica. CONCLUSÃO: A detecção precoce de exposição ao álcool na vida intrauterina pode ser realizada e é um instrumento para prevenir efeitos secundários, porque possibilita a intervenção farmacológica e educacional na criança com DEAF.

BACKGROUND: Prenatal exposure to ethanol can produce a complex set of effects on fetal development, which is denominated fetal alcohol spectrum disorder (FASD). Early detection of ethanol exposure can allow the prevention of some relevant adverse effects associated to FASD. OBJECTIVES: The aim of this work was to review the main toxic effects of ethanol on the neonate and the available biomarkers of prenatal alcohol exposure. METHODS: A bibliographic search was performed in PubMed employing the terms "effects maternal ethanol exposure" and "biomarkers ethanol prenatal exposure" and cross references. RESULTS: Many adverse effects on fetal development were described, especially deficits in the central nervous system. The biomarkers of ethanol exposure more widely described were fatty acid ethyl esters (FAEEs), ethyl glucuronide (EtG) and ethyl sulphate (EtS), being meconium and hair the most common biological matrices for laboratorial evaluation. DISCUSSION: The early detection of alcohol exposure in intra-uterine life is useful to prevent the secondary effects of FASD through pharmacologic and educational intervention in affected children.

Occupational risk assessment of genotoxicity and oxidative stress in workers handling anti-neoplastic drugs during a working week.

Twenty pharmacists and nurses handling anti-neoplastic drugs in a hospital were monitored during a working week, from Monday to Friday, in the morning (only on Monday) and afternoon (all days). Genotoxicity was analysed by the comet assay and the micronucleus (MN) test, while oxidative stress was analysed in serum by thiobarbituric acid reactive substances (TBARS) and by measurements of the antioxidant enzymes superoxide dismutase (Sod) and catalase (Cat). The exposed workers presented increased DNA damage levels by the comet assay as compared to the controls. The comet assay results have also shown significant positive correlation with the day of the week and with alcohol consumption. MN frequency was significantly higher in the exposed workers and presented noteworthy correlation with age and working time. In the oxidative stress parameters, only Cat presented a significant increase in the exposed group, considering all the samplings. However, TBARS data showed interesting results, considering the different sampling times; the exposed group presented a significant correlation with the working days and significantly higher results on Friday as compared to the controls and Monday morning. Monitoring occupational risk during a longer time, e.g. during a working week as done in this study, introduces additional aspects of risk behaviour, which can improve risk management. This study demonstrates the usefulness of evaluating oxidative stress also in genotoxic risk assessment since both events often result from the same factors.

Association of low repair efficiency with high hormone receptors expression and SOD activity in breast cancer patients.

OBJECTIVES: To evaluate the antioxidant status and repair capacity in breast cancer patients as well as the relationship between these parameters and expression of critical proteins in breast cancer tissue. DESIGN AND METHODS: Blood samples were obtained from 25 female breast cancer patients and 19 healthy women. The antioxidant status was determined by the concentration of thiobarbituric-reactive substances (TBARS) and activity of superoxide dismutase (SOD) and catalase (CAT). The basal DNA damage and repair capacity in lymphocytes were evaluated by comet assay. The expression of p53, c-erbB2, Ki-67, estrogen receptor (ER) and progesterone receptor (PR) in cancer tissue was detected by immunohistochemical staining. RESULTS: The breast cancer patients presented significantly elevated endogenous DNA damage in lymphocytes and lower susceptibility to DNA damage induced by H(2)O(2) when compared to the control group. There is a negative correlation between TBARS and sensitivity to peroxide induced DNA damage in patients. The percentage of residual damage after H(2)O(2) treatment followed by 3h of post-incubation is significantly higher in patients and also correlates positively with SOD activity, ER and PR expression and negatively with the basal DNA damage. CONCLUSIONS: Our results demonstrate low repair capacity in lymphocytes of breast cancer patients and suggest that the regulation of DNA repair is sensitive to cellular redox state and can be modulated by ER/PR status.

DNA damage in rats after treatment with methylphenidate.

BACKGROUND: Methylphenidate (MPH) is a widely prescribed psychostimulant for the treatment of attention-deficit hyperactivity disorder (ADHD). Recently, some studies have addressed the genotoxic potential of the MPH, but the results have been contradictory. Hence, the present study aimed to investigate the index of cerebral and peripheral DNA damage in young and adult rats after acute and chronic MPH exposure. METHODS: We used (1) single cell gel electrophoresis (Comet assay) to measure early DNA damage in hippocampus, striatum and total blood, and (2) micronucleus test in total blood samples. RESULTS: Our results showed that MPH increased the peripheral index of early DNA damage in young and adult rats, which was more pronounced with chronic treatment and in the striatum compared to the hippocampus. Neither acute nor chronic MPH treatment increased micronucleus frequency in young or in adult rats. Peripheral DNA damage was positively correlated with striatal DNA damage. CONCLUSION: These results suggest that MPH may induce central and peripheral early DNA damage, but this early damage may be repaired.

Serum S100B and antioxidant enzymes in bipolar patients.

Bipolar disorder (BD) is a chronic, severe, and highly disabling psychiatric disorder; peripheral markers have been used to assess biochemical alterations associated with BD and/or possibly involved in its pathophysiology. Beyond neuronal commitment, many groups have proposed the involvement of glial activity in psychiatric disorders. Other biochemical markers, particularly associated with oxidative stress, have been studied in BD. In the present study, we evaluated glial involvement and oxidative stress in patients with BD. Glial activity was assessed by measuring serum S100B content; oxidative stress was assessed using serum thiobarbituric acid reactive substances (TBARS) and activities of antioxidant enzymes in BD patients during different episodes of disease. We found a significant increment of serum S100B during episodes of mania and depression, but not in euthymic patients. Superoxide dismutase (SOD) activity, as well the SOD/glutathione peroxidase plus catalase ratio, was also increased in manic and depressed patients. On the other hand, TBARS levels were increased in BD patients regardless of the phase of the disorder. These findings suggest a potential oxidative damage in BD patients. This peripheral oxidative imbalance indicates that systemic changes are taking place during the active phases of the illness. Such changes appear to relate to astrocyte function, as indicated by serum S100B elevation.