Cytoprotective and genoprotective effects of taxifolin against oxidative damage in HTR-8/SVneo human trophoblast cells.

An increase of reactive oxygen species in the placenta and oxidative disbalance has been recognized as a significant factor contributing to pregnancy complications. Dietary intake of food rich in antioxidants during pregnancy could exert a protective role in the prevention of adverse outcomes such as preeclampsia, miscarriage, and others. Flavonoid taxifolin has shown numerous health-promoting effects in a large number of studies conducted on animals, as well as various human cell types in vitro. However, its effects on human placental cells-trophoblasts-have yet to be determined. Therefore, cytoprotective and genoprotective effects of taxifolin on trophoblast cell line HTR-8/SVneo under induced oxidative stress were explored in this study. Cytotoxicity of a range of taxifolin concentrations (1-150 µM) was evaluated using the MTT and crystal violet assays. A model of oxidative stress was achieved by exposing HTR-8/SVneo cells to H2O2. To determine cytoprotective and antigenotoxic effects, the cells were pre-incubated with three concentrations of taxifolin (10, 50, and 100 µM) and then exposed to H2O2. Taxifolin in concentrations of 1, 5, 10, 25, 50, and 100 µM showed no cytotoxic effects on HTR-8/SVneo cells, but 150 µM of taxifolin caused a significant decrease in adherent cell number, as detected by crystal violet assay. Pretreatment with the chosen concentrations of taxifolin showed a significant cytoprotective effect on H2O2-induced cytotoxicity, as determined by the MTT assay. Furthermore, taxifolin showed a significant reduction in H2O2-induced DNA damage, measured by comet assay. This study showed protective effects of taxifolin on human trophoblast cells exposed to oxidative damage. Further studies are needed to explore the underlying mechanisms.

Comparative analysis of Ag NPs functionalized with olive leaf extract and oleuropein and toxicity in human trophoblast cells and peripheral blood lymphocytes.

Dry olive leaf extract (DOLE) and its active component oleuropein (OLE) were applied as reducing and stabilizing agents to prepare colloidal 20-25 nm silver nanoparticles (Ag NPs). The Ag NPs were characterized using transmission electron microscopy, X-ray diffraction analysis, and absorption spectroscopy. The cytotoxic actions of coated Ag NPs, and their inorganic and organic components, were examined against trophoblast cells and human peripheral blood lymphocytes (PBLs), Gram-positive, Gram-negative bacteria, and yeast. The genotoxic potential was evaluated in PBLs in vitro with the comet assay. Ag/DOLE and Ag/OLE induced cytotoxic effects in both types of cells after 24 h exposure when silver concentrations were 0.025-0.2 mM. However, the most pronounced cytotoxicity exhibits Ag/OLE. Both colloids also caused reduced ROS production in both cell types at 0.1 mM and 0.2 mM, while bare Ag NPs did not alter ROS levels at any of the conditions. Functionalized Ag/DOLE and Ag/OLE did not show genotoxic effects in PBLs, while bare AgNPs increased DNA damage significantly only at 0.2 mM. Regarding the antimicrobial effects, the Ag/OLE had MIC values for all evaluated microorganisms from 0.0625 to less than 0.0312 mM. Also, the antimicrobial effect of Ag/DOLE was significantly higher on Gram-negative bacteria and yeast than on Gram-positive bacteria. Obtained results indicate that Ag/OLE induced the most pronounced biological effects, beneficial for its application as an antimicrobial agent, but with potential risks from exposure to high concentrations that could induce cytotoxicity in healthy human cells.

Nepeta rtanjensis (Lamiaceae), a plant endemic to the Balkans: Phenolic composition, antioxidant activity, and in vitro antigenotoxic effects in triiodothyronine-induced DNA damage in human lymphocytes.

The success of antioxidant therapy in hyperthyroidism implies that disease is mediated by oxidative stress, which is known as one of the causing agents of ageing, degenerative diseases, and cancer. The main objective of our study was to determine possible protective effects of methanolic extract of N. rtanjensis in triiodothyronine (T3)-induced DNA breaks of human lymphocytes under in vitro conditions, based upon plant antioxidant capacity related to its phytochemical profile, mainly its polyphenolic complex. The total phenolic and flavonoid content and the antioxidant activity using in vitro 1,1-dyphenyl-2- picrylhydrazyl reagent (DPPH) was determined in methanolic extracts of plant leaves and flowers. The phenolic compound content of 62.73±1.80mg of GaA/g, exhibited solid antioxidant activity (IC50= 112.59±0.95µg/ml). The antigenotoxic activity of 0.2, 0.5 and 1.0mg/ml N. rtanjensis methanol extracts mixture with 100µM of T3 was studied in human lymphocytes in vitro using the Comet assay. It is supposed that the antigenotoxicity of N. rtanjensis methanol extracts was caused by high presence of chlorogenic acid, rosmarinic acid and rutin, all known as efficient antioxidant bioactive compounds, which were determined by ultrahigh-pressure liquid chromatograph with MS/MS Mass Spectroscopy (UHPLC/-HESI-MS / MS).

Cordyceps sinensis: Genotoxic Potential in Human Peripheral Blood Cells and Antigenotoxic Properties Against Hydrogen Peroxide by Comet Assay.

Context • Cordyceps sinensis (C sinensis) is a well-known, traditional, Chinese medicinal mushroom, valued for its beneficial properties for human health. C sinensis has been reported to have immunomodulatory, anticancer, antiaging, antioxidant and anti-inflammatory activity. Despite potential medicinal benefits, no previously published reports are available about the genotoxicity or antigenotoxicity of C sinensis, as detected by comet assay. Objective • The objective of the study was to evaluate both the genotoxic and antigenotoxic potential of an extract of C sinensis (CS extract) in human peripheral blood cells. Design • The research team designed a pilot study. Setting •The study was conducted at the Center for Biological Research, University of Belgrade, in Belgrade, Serbia. Participants • Participants were 6 healthy individuals (2 males and 4 females), between the ages of 20 and 45 y, recruited on a voluntary basis, who provided heparinized, peripheral blood samples. Intervention • Four concentrations of the CS extract-125 µg/mL, 250 µg/mL, 500 µg/mL, and 1000 µg/mL-were used in the treatment of tested blood cells from the blood samples. Three independent procedures were performed: (1) a genotoxicity assessment, (2) an antigenotoxicity assessment for pretreatment of human cells with the CS extract prior to their exposure to hydrogen peroxide (H2O2) (ie, an evaluation of the benefits of the CS extract as a preventive agent); and (3) posttreatment of human cells with the CS extract after their exposure to H2O2 (ie, an evaluation of the benefits of the CS extract as an interventional agent). Outcome Measures • Cells were graded by eye inspection into 5 classes, depending on the extent of DNA damage, representing: (1) class A-undamaged cells with no tail (<5% damaged DNA); (2) class B-low-level damage (5%-20%); (3) class C-medium-level damage (20%-40%); (4) class D-high-level damage (40%-95%), and (5) class E-total destruction (>95%).Results • The CS extract proved to be nongenotoxic because no induced DNA damage was detected at all tested concentrations. For the antigenotoxicity assessment of the pretreatment with the CS extract, only the 1000-µg/mL concentration showed a significant decrease in the number of cells exhibiting H2O2-induced DNA damage. For the posttreatment, the CS extract exhibited antigenotoxic potential by attenuating H2O2-induced DNA damage at all concentrations tested. The evaluation of repair kinetics showed a decrease in DNA-damaged cells 15 min after the application of the CS extract, reaching a maximum potency after 45 min. Conclusions • The results indicated that C sinensis can be used as a postapplicative agent that counteracts the effect of oxidative stress. The resulting reduction in DNA damage might be related to its scavenging properties and stimulation of DNA repair.

Dry Olive Leaf Extract in Combination with Methotrexate Reduces Cell Damage in Early Rheumatoid Arthritis Patients-A Pilot Study.

The effects of co-administration of dry olive leaf extract (DOLE) with standard methotrexate (MTX) therapy on the parameters of cell damage and inflammation in patients with early and long-term rheumatoid arthritis (RA) were evaluated at baseline, 3 and 6 weeks. Patients were assigned to groups: the early phase RA group on MTX monotherapy (E MTX), and the two RA groups that received co-treatment with DOLE and MTX: early (E MTX + DOLE) and long-term phase patients (L-t MTX+ DOLE). Baseline values indicated increased parameters of cell damage and disruption of redox balance in all groups. After three weeks the E MTX + DOLE group maintained high catalase activity, exhibited decrease of lipid peroxidation and protein damage indicators-thiols and nitrites, while levels of DNA damage and pro-inflammatory interleukin-6 were significantly reduced. In E MTX group catalase activity remained unaltered while significant lipid peroxidation and DNA damage reductions were seen only after six weeks. L-t MTX + DOLE group showed only modest alterations of cell damage parameters during six weeks. Combined administration of DOLE with MTX contributes to faster reduction of cell damage, restores oxidative balance and improves interleukin-6 suppression during high disease activity in early phase RA, but not in long term patients. Copyright © 2016 John Wiley & Sons, Ltd.

Antigenotoxic Effect of Trametes spp. Extracts against DNA Damage on Human Peripheral White Blood Cells.

Trametes species have been used for thousands of years in traditional and conventional medicine for the treatment of various types of diseases. The goal was to evaluate possible antigenotoxic effects of mycelium and basidiocarp extracts of selected Trametes species and to assess dependence on their antioxidant potential. Trametes versicolor, T. hirsuta, and T. gibbosa were the species studied. Antigenotoxic potentials of extracts were assessed on human peripheral white blood cells with basidiocarp and mycelium extracts of the species. The alkaline comet test was used for detection of DNA strand breaks and alkali-labile sites, as well as the extent of DNA migration. DPPH assay was used to estimate antioxidative properties of extracts. Fruiting body extracts of T. versicolor and T. gibbosa as well as T. hirsuta extracts, except that at 20.0 mg/mL, were not genotoxic agents. T. versicolor extract had at 5.0 mg/mL the greatest antigenotoxic effect in both pre- and posttreatment of leukocytes. The mycelium extracts of the three species had no genotoxic activity and significant antigenotoxic effect against H2O2-induced DNA damage, both in pre- and posttreatment. The results suggest that extracts of these three species could be considered as strong antigenotoxic agents able to stimulate genoprotective response of cells.

Identification of p53 and its isoforms in human breast carcinoma cells.

In breast carcinoma, disruption of the p53 pathway is one of the most common genetic alterations. The observation that the p53 can express multiple protein isoforms adds a novel level of complexity to the outcome of p53 mutations. p53 expression was analysed by Western immunoblotting and immunohistochemistry using monoclonal antibodies DO-7, Pab240, and polyclonal antiserum CM-1. The more frequently p53-positive nuclear staining has been found in the invasive breast tumors. One of the most intriguing findings is that mutant p53 appears as discrete dot-shaped regions within the nucleus of breast cancer cells. In many malignant cells, the nucleolar sequestration of p53 is evident. These observations support the view that the nucleolus is involved directly in the mediation of p53 function or indirectly by the control of the localization of p53 interplayers. p53 expressed in the nuclear fraction of breast cancer cells revealed a wide spectrum of isoforms. p53 isoforms ΔNp53 (47 kDa) and Δ133p53 ß (35 kDa), known as dominant-negative repressors of p53 function, were detected as the most predominant variants in nuclei of invasive breast carcinoma cells. The isoforms expressed also varied between individual tumors, indicating potential roles of these p53 variants in human breast cancer.

Antioxidative and anti-inflammatory effects of taxifolin in H2O2-induced oxidative stress in HTR-8/SVneo trophoblast cell line.

Oxidative stress has been implicated in numerous pregnancy-related disorders. Biologically active plant secondary metabolites, which are present in everyday diet, could prove effective therapeutic agents in preventing these disorders. This study evaluated effects of taxifolin (dihydroquercetin) on ROS production, markers of oxidative damage to lipids and proteins, activity of antioxidant enzymes and production of pro-inflammatory cytokines in H2O2-induced oxidative stress in trophoblast HTR-8/SVneo cells. Taxifolin in 10 µM and 100 µM concentrations attenuated oxidative damage to lipids and proteins, as evidenced by a decrease in MDA content, extracellular LDH activity, carbonyl groups and nitrite contents. A reduction in the activity of antioxidant enzymes SOD, CAT and GPx in cells pre-treated with taxifolin, prior to H2O2 exposure, was also observed, along with a reduction in intracellular ROS production. Both evaluated concentrations of taxifolin showed anti-inflammatory activity in trophoblast cells, by reducing production of pro-inflammatory cytokines IL-1ß and IL-6. In this model of H2O2-induced oxidative stress, taxifolin showed marked antioxidative and anti-inflammatory activities in trophoblast cells, adding further evidence of its protective effects and showing potential as a therapeutic agent in preventing adverse pregnancy outcomes.

Cu(II) complexes with a salicylaldehyde derivative and α-diimines as co-ligands: synthesis, characterization, biological activity. Experimental and theoretical approach.

Copper(II) complexes with an α-diimine show a wide variety of biological activities, such as antibacterial, antifungal, antioxidant and anticancer. In this work, we synthesized and structurally characterized two novel Cu(II) complexes with methyl 3-formyl-4-hydroxybenzoate (HL) and α-diimines: 2,2'-bipyridine (bipy) and 1,10-phenanthroline (phen). Crystal structure analysis shows that the formulas of the compounds are [Cu(bipy)(L)(BF4)] (1) and [Cu(phen)(L)(H2O)](BF4)·H2O (2), with BF4- as a ligand in complex 1, which is rarely coordinated to metals. Both complexes have a square pyramidal geometry, while DFT calculations showed that the most stable structures of complexes 1 and 2 in a water/DMSO mixture are square-planar derivatives [Cu(bipy)(L)]+ and [Cu(phen)(L)]+. The antibacterial activity of compounds was evaluated in vitro on four Gram-negative and four Gram-positive bacterial strains. Complex 2 showed greater antibacterial activity towards all bacterial strains comparable to the control compound Amikacin. Complex 2 exerted a strong cytotoxic effect against the tested cancer cell lines (IC50 values ranging from 0.32 to 0.44 µM). Both complexes caused apoptotic cell death in HeLa cells and a noticeable in vitro antiangiogenic effect. In the concentration range of 5 to 100 µM, the complexes showed the absence of a genotoxic effect and displayed a protective effect against oxidative DNA damage induced by H2O2 in human peripheral blood cells. The interaction between the compounds and calf-thymus DNA was evaluated by diverse techniques suggesting a tight binding, which was also confirmed by molecular docking. In addition, it was found that the complexes bind tightly and reversibly to bovine and human serum albumin.

DNA damage in Alzheimer disease lymphocytes and its relation to premature centromere division.

While Alzheimer disease (AD) is considered a neurodegenerative disorder, the importance of chromosome instability in non-neuronal cells is equally important, not only for shedding light on the etiology of the disease, but also for possible diagnostic purposes and monitoring the progress of the disease. Here, we evaluated the frequency of DNA damage and expression of premature centromere division (PCD) in peripheral blood lymphocytes of sporadic AD patients, age-matched and young controls. The results show that in male patients with AD, the frequencies of PCD and DNA damage were significantly greater (88%, p<0.01 and 38%, p<0.05, respectively) than in age-matched control group. AD females had significantly increased frequency of PCD (134%, p<0.01) as well as a higher frequency of DNA damage (37%, p<0.05). Ageing per se, both in males and females, shows significant increase of percentages of PCD (2.3 times, p<0.01 and 2.8 times, p<0.01, respectively) and DNA damage (63%, p<0.01 and 50%, p<0.01, respectively) comparing with young controls. In addition, a strong (R2=0.873, n=6) and significant (p<0.01) correlation between the frequencies of PCD and DNA damage was found in all examined groups. We may conclude that the increases in both parameters evaluated in this study are not only associated with normal ageing processes, but are markedly and significantly intensified in AD pathogenesis. Thus, our data support the view that AD is a generalized systemic disease, at least as for the increased DNA damage and PCD incidence in peripheral blood cells.

DES-Amyloidoses "Amyloidoses through the looking-glass": A knowledgebase developed for exploring and linking information related to human amyloid-related diseases.

More than 30 types of amyloids are linked to close to 50 diseases in humans, the most prominent being Alzheimer's disease (AD). AD is brain-related local amyloidosis, while another amyloidosis, such as AA amyloidosis, tends to be more systemic. Therefore, we need to know more about the biological entities' influencing these amyloidosis processes. However, there is currently no support system developed specifically to handle this extraordinarily complex and demanding task. To acquire a systematic view of amyloidosis and how this may be relevant to the brain and other organs, we needed a means to explore "amyloid network systems" that may underly processes that leads to an amyloid-related disease. In this regard, we developed the DES-Amyloidoses knowledgebase (KB) to obtain fast and relevant information regarding the biological network related to amyloid proteins/peptides and amyloid-related diseases. This KB contains information obtained through text and data mining of available scientific literature and other public repositories. The information compiled into the DES-Amyloidoses system based on 19 topic-specific dictionaries resulted in 796,409 associations between terms from these dictionaries. Users can explore this information through various options, including enriched concepts, enriched pairs, and semantic similarity. We show the usefulness of the KB using an example focused on inflammasome-amyloid associations. To our knowledge, this is the only KB dedicated to human amyloid-related diseases derived primarily through literature text mining and complemented by data mining that provides a novel way of exploring information relevant to amyloidoses.

Copper(II) complexes with 4-(diethylamino)salicylaldehyde and α-diimines: Anticancer, antioxidant, antigenotoxic effects and interaction with DNA and albumins.

In this article, cytotoxicity, the mechanisms of cytotoxic activity, genotoxicity, and interaction with DNA and proteins, of two Cu(II) complexes with a salicylaldehyde derivative (4-(diethylamino)salicylaldehyde) and α-diimine (2,2'-bipyridine (bipy) and 1,10-phenanthroline (phen)) are reported. Both Cu(II) complexes performed cytotoxic effects against all tested malignant cell lines. Complexes exerted highest cytotoxicity against HeLa and A375 malignant cell lines. The cytotoxic activity of Cu(II) complex with phen as a α-diimine co-ligand was significantly higher in comparison with cytotoxic activity of Cu(II) complex with bipy. Pretreatment with specific inhibitors of caspase-3, caspase-8 or caspase-9, in order to clear up the mode of cell death triggered by two Cu(II) complexes in HeLa cells, indicated the ability of these complexes to induce apoptosis through activation of target caspases. Cu(II)-phen complex exhibited significant antioxidant activity compared with Cu(II)-bipy complex, and showed a better effect on reducing intracellular ROS levels in HeLa cells. Tested complexes did not display genotoxic potential in human peripheral blood leucocytes, but exhibited an antigenotoxic effect in post-treatment, after H2O2 exposure. The study of the in vitro biological properties regarding their affinity towards CT (calf-thymus) DNA and serum albumins showed that the compounds can intercalate to CT DNA, and bind reversibly and tightly to the albumins. Molecular docking studies of the ability of compounds to bind to biomacromolecules are consistent with in vitro studies.

Toxicity of Silver Nanoparticles Supported by Surface-Modified Zirconium Dioxide with Dihydroquercetin.

The antibacterial performance and cytotoxic examination of in situ prepared silver nanoparticles (Ag NPs), on inorganic-organic hybrid nanopowder consisting of zirconium dioxide nanoparticles (ZrO2 NPs) and dihydroquercetin (DHQ), was performed against Gram (-) bacteria Escherichia coli and Gram (+) bacteria Staphylococcus aureus, as well as against human cervical cancer cells HeLa and healthy MRC-5 human cells. The surface modification of ZrO2 NPs, synthesized by the sol-gel method, with DHQ leads to the interfacial charge transfer (ICT) complex formation indicated by the appearance of absorption in the visible spectral range. The prepared samples were thoroughly characterized (TEM, XRD, reflection spectroscopy), and, in addition, the spectroscopic observations are supported by the density functional theory (DFT) calculations using a cluster model. The concentration- and time-dependent antibacterial tests indicated a complete reduction of bacterial species, E. coli and S. aureus, for all investigated concentrations of silver (0.10, 0.25, and 0.50 mg/mL) after 24 h of contact. On the other side, the functionalized ZrO2 NPs with DHQ, before and after deposition of Ag NPs, do not display a significant decrease in the viability of HeLa MRC-5 cells in any of the used concentrations compared to the control.

Mislocalization of CDK11/PITSLRE, a regulator of the G2/M phase of the cell cycle, in Alzheimer disease.

Post-mitotic neurons are typically terminally differentiated and in a quiescent status. However, in Alzheimer disease (AD), many neurons display ectopic re-expression of cell cycle-related proteins. Cyclin-dependent kinase 11 (CDK11) mRNA produces a 110-kDa protein (CDK11(p110)) throughout the cell cycle, a 58-kDa protein (CDK11(p58)) that is specifically translated from an internal ribosome entry site and expressed only in the G(2)/M phase of the cell cycle, and a 46-kDa protein (CDK11(p46)) that is considered to be apoptosis specific. CDK11 is required for sister chromatid cohesion and the completion of mitosis. In this study, we found that the expression patterns of CDK11 vary such that cytoplasmic CDK11 is increased in AD cellular processes, compared to a pronounced nuclear expression pattern in most controls. We also investigated the effect of amyloid precursor protein (APP) on CDK11 expression in vitro by using M17 cells overexpressing wild-type APP and APP Swedish mutant phenotype and found increased CDK11 expression compared to empty vector. In addition, amyloid-ß(25-35) resulted in increased CDK11 in M17 cells. These data suggest that CDK11 may play a vital role in cell cycle re-entry in AD neurons in an APP-dependent manner, thus presenting an intriguing novel function of the APP signaling pathway in AD.

DNA, protein and lipid oxidative damage in tissues of spontaneously hypertensive versus normotensive rats.

Oxidative damage to protein and lipid macromolecules in target organs in hypertension has been recognized as a major factor contributing to cardiovascular, cerebrovascular, and renal diseases. Data on protein and lipid oxidative damage in spontaneously hypertensive rats are numerous, but there is no information on DNA damage in tissues measured by comet assay. The aim of this study was to determine the baseline damage to DNA, protein, and lipid macromolecules in different organs of spontaneously hypertensive rats. Markers of lipid peroxidation, protein oxidation, and DNA damage were measured in blood, heart, kidney, and liver of 24-week-old spontaneously hypertensive rats. Plasma prooxidant and antioxidant status were determined as well. Age-matched normotensive Wistar rats were used as control. A rise in markers of lipid peroxidation and protein oxidation, malondialdehyde, and advanced oxidation protein products, was detected in all tissues of spontaneously hypertensive rats, with particularly high values in the liver. DNA damage, measured by the comet assay, was significantly higher in all the studied tissues of spontaneously hypertensive rats compared to normotensive control, with more severe damage in the cardiac and renal cells. Significant depletion of the plasma antioxidant barrier in spontaneously hypertensive rats was also observed. This study showed increased damage to all macromolecules in all studied samples of spontaneously hypertensive rats in comparison with control Wistar rats.

Strawberry (Fragaria ananassa duch.) Alba extract attenuates DNA damage in lymphocytes of patients with Alzheimer's disease.

Increased levels of oxidative stress and oxidative DNA damage are common features in the pathology of Alzheimer's disease (AD) found in neurons and peripheral cells like peripheral blood lymphocytes (PBL). Natural products such as strawberry cultivar Alba are an important source of bioactive nutrients that could help in lowering both the oxidative stress and DNA damage levels. The objective was to estimate the effects of Alba extract on DNA damage in peripheral blood lymphocytes of sporadic AD (aged 60-84 years) patients, and healthy elderly (aged 69-83 years) and young (aged 21-30 years) individuals in in vitro conditions. Comet assay was used as a sensitive technique for the evaluation of PBL DNA damage levels. Reduction of basal DNA damage level in PBL was shown in the young group after the incubation with Alba extract ranging from 25 to 200 µg/ml, with 100 µg/ml being the most effective concentration. Selected Alba extract of 100 µg/ml was further used for PBL treatment of AD and healthy elderly age matched group, displaying potential to significantly attenuate DNA damage levels in both groups (p < .05). Alba extract displayed biological activity against oxidative DNA damage, suggesting that its functional ingredients may have beneficial health effects. PRACTICAL APPLICATIONS: The data obtained in this preliminary study displayed that strawberry Alba extract is efficient against DNA damage induced by endogenous and exogenous oxidative stress in peripheral blood lymphocytes of Alzheimer`s disease in vitro. An active area of future research of Alba cultivar should be to determine the trials in in vivo systems. Our findings also suggest that Alba cultivar's functional ingredients potentially may have beneficial health effects in AD.

Antioxidant, Antigenotoxic and Cytotoxic Activity of Essential Oils and Methanol Extracts of Hyssopus officinalis L. Subsp. aristatus (Godr.) Nyman (Lamiaceae).

Hyssopus officinalis L. is a well-known aromatic plant used in traditional medicine and the food and cosmetics industry. The aim of this study is to assess the antioxidant, genotoxic, antigenotoxic and cytotoxic properties of characterized hyssop essential oils and methanol extracts. Chemical composition was analyzed by gas chromatography - mass spectrometry (GC-MS) and liquid chromatography with diode array detection and mass spectrometry (LC-DAD-MS), respectively. Antioxidant activity was examined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing/antioxidant power (FRAP) tests; genotoxic and antigenotoxic activity were examined by the comet assay, while cytotoxicity was evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide dye (MTT) test against tumor cell lines (SW480, MDA-MB 231, HeLa) and non-transformed human lung fibroblast cell lines (MRC-5). The essential oils were rich in monoterpene hydrocarbons (e.g., limonene; 7.99-23.81%), oxygenated monoterpenes (1,8-cineole; 38.19-67.1%) and phenylpropanoids (methyl eugenol; 0.00-28.33%). In methanol extracts, the most abundant phenolics were chlorogenic and rosmarinic acid (23.35-33.46 and 3.53-17.98 mg/g, respectively). Methanol extracts expressed moderate to weak antioxidant activity (DPPH IC50 = 56.04-199.89 µg/mL, FRAP = 0.667-0.959 mmol Fe2+/g). Hyssop preparations significantly reduced DNA damage in human whole blood cells, induced by pretreatment with hydrogen peroxide. Methanol extracts exhibited selective and potent dose- and time-dependent activity against the HeLa cell line. Results of the current study demonstrated notable H. officinalis medicinal potential, which calls for further investigation.

DNA damage in circulating leukocytes measured with the comet assay may predict the risk of death.

The comet assay or single cell gel electrophoresis, is the most common method used to measure strand breaks and a variety of other DNA lesions in human populations. To estimate the risk of overall mortality, mortality by cause, and cancer incidence associated to DNA damage, a cohort of 2,403 healthy individuals (25,978 person-years) screened in 16 laboratories using the comet assay between 1996 and 2016 was followed-up. Kaplan-Meier analysis indicated a worse overall survival in the medium and high tertile of DNA damage (p < 0.001). The effect of DNA damage on survival was modelled according to Cox proportional hazard regression model. The adjusted hazard ratio (HR) was 1.42 (1.06-1.90) for overall mortality, and 1.94 (1.04-3.59) for diseases of the circulatory system in subjects with the highest tertile of DNA damage. The findings of this study provide epidemiological evidence encouraging the implementation of the comet assay in preventive strategies for non-communicable diseases.

Antioxidant enzymes expression in lymphocytes of patients undergoing carotid endarterectomy.

To remedy carotid artery stenosis and prevent stroke surgical intervention is commonly used, and the gold standard being carotid endarterectomy (CEA). During CEA cerebrovascular hemoglobin oxygen saturation decreases and when this decrease reaches critical levels it leads to cerebral hypoxia that causes neuronal damage. One of the proposed mechanism that affects changes during CEA and contribute to acute brain ischemia (ABI) is oxidative stress. The increased production of reactive oxygen species and reactive nitrogen species during ABI may cause an unregulated inflammatory response and further lead to structural and functional injury of neurons. Antioxidant activity are involved in the protection against neuronal damage after cerebral ischemia. We hypothesized that neuronal injury and poor outcomes in patients undergoing CEA may be results of oxidative stress that disturbed function of antioxidant enzymes and contributed to the DNA damage in lymphocytes.

Antigenotoxic Effects of Biochaga and Dihydroquercetin (Taxifolin) on H2O2-Induced DNA Damage in Human Whole Blood Cells.

The health benefits of natural products have long been recognized. Consumption of dietary compounds such as supplements provides an alternative source of natural products to those obtained from the diet. There is a growing concern regarding the possible side effects of using different food supplements simultaneously, since their possible interactions are less known. For the first time, we have tested genotoxic and antigenotoxic effects of Biochaga, in combination with dihydroquercetin. No genotoxic effect on whole blood cells was observed within individual treatment of Biochaga (250 µg/mL, 500 µg/mL and 1000 µg/mL) and dihydroquercetin (100 µg/mL, 250 µg/mL and 500 µg/mL), nor in combination. Afterwards, antigenotoxic potency of both supplements against hydrogen peroxide- (H2O2-) induced DNA damage to whole blood cells (WBC) was assessed, using the comet assay. Biochaga and dihydroquercetin displayed a strong potential to attenuate H2O2-induced damage on DNA in cells at all tested concentrations, with a statistical significance (p < 0.05), whereas Biochaga at the dose of 500 µg/mL in combination with dihydroquercetin 500 µg/mL was most prominent. Biochaga in combination with dihydroquercetin is able to protect genomic material from oxidative damage induced by hydrogen peroxide in vitro.