1,721,063 research outputs found
DNA damage and oxidative stress in cell fish line RTG-2 after exposure to PCB mixture(PCB153,138, 101, 118)
No full textProtective effect of Vaccinium myrtillus extract against UVA- and UVB-induced damage in a human keratinocyte cell line (HaCaT cells)
No full textRecently, the field of skin protection have shown a considerable interest in the use of botanicals. Vaccinium myrtillus contains several polyphenols and anthocyanins with multiple pharmacological properties. The purpose of our study was to examine whether a water-soluble V. myrtillus extract (dry matter 12.4%; total polyphenols 339.3 mg/100 g fw; total anthocyanins 297.4 mg/100 g fw) was able to reduce UVA- and UVB-induced damage using a human keratinocyte cell line (HaCaT). HaCaT cells were pretreated for 1 h with extract in a serum-free medium and then irradiated with UVA (8-40 J/cm(2)) and UVB (0.008-0.72 J/cm(2)) rays. All experiments were performed 24 h after the end of irradiation, except for oxidative stress tests. The extract was able to reduce the UVB-induced cytotoxicity and genotoxicity (studied by comet and micronucleous assays) at lower doses. V. myrtillus extract reduced lipid peroxidation UVB-induced, but had no effect against the ROS UVB-produced. With UVA-induced damage V. myrtillus reduced genotoxicity as well as the unbalance of redox intracellular status. Moreover our extract reduced the UVA-induced apoptosis, but had no effect against the UVB one. V. myrtillus extract showed its free radical scavenging properties reducing oxidative stress and apoptotic markers, especially in UVA-irradiated cells
Effect of four higly bioaccumulated polychlorinated biphenyls (PCBs) alone and in mixture in MCF-7 breast carcinoma cell line
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Possible estrogenic effects of some higly bioaccumulated polychlorinated biphenyls (PCB101, 118,138,153) alone and in mixture in MCF-7 breast cancer cells
No full textPolychlorinated biphenyls (PCBs) are ubiquitous environmental persistent contaminants giving rise to potential health hazard. Depending on the position and number of chlorine substitutions, different classes of PCB congeners elicit a complex spectrum of biological and toxic responses in a number of models in vivo and in vitro. Moreover, some PCBs have been shown to have potential estrogen and anti-estrogen effects.
In the present study we have analysed the potential estrogenic effect in MCF-7 cells of four very biologically relevant PCB congeners alone and in mixture: PCB 101 (2,2′,4,5,5′-pentachlorobiphenyl), PCB 118 (2,3′,4,4′,5-pentachlorobiphenyl), PCB 138 (2,2′,4,4′,5,5′-hexachlorobiphenyl) and PCB 153 (2,2′,3,4′,5,5′-heptachlorobiphenyl).
The mixture of four PCBs was tested at seven different concentration chosen on the basis of their recovery from crop and some foods. The ability of these PCBs alone and in mixture to induce cell proliferation and the level of estrogen-regulated protein pS2 were studied using the human MCF-7 breast cancer cells.
In this cell line, only PCB 153 (35 μM) stimulates cell proliferation from 48 h up to 6th day, while PCB 118 (40 μM) only at 48 h. No effect was observed after treatment with PCB 101 (45 μM) and PCB 138 (10 μM) until 6 days. The treatment with different mixture concentrations causes a significant decrease of cell proliferation at different time. No variation of pS2 level was observed after treatment with the different PCBs alone and in mixture.
In exploring the molecular mechanism and the kinetic of these events, we found that PCB 153 was able to induced mitogen-activated protein kinase (MAPK) ERK1/2 at 4, 8 and 12 h, while the anti-proliferative effect seems to be mediated by an apoptotic action beginning at 12 and ending at 48 h
In vitro DNA damage in derived cell fish(RTG-2)after short and long term exposure to PCBs (153,138,101,138)
No full textProtective effect of erdosteine metabolite I against hydrogen peroxide-induced oxidative DNA-damage in lung epithelial cells
No full textIt has been shown that the mucolytic agent erdosteine (N- carboxymethylthioacetyl-homocysteine thiolactone, CAS 84611-23-4) has anti-inflammatory and anti-oxidant properties, and an active metabolite I (MET I) containing pharmacologically active sulphydryl group has been found to have a free radical scavenging activity. The aim of this study was to assess the ability of erdosteine metabolite I to protect A549 human lung adenocarcinoma cell against hydrogen peroxide (H2O2)-mediated oxidative stress and oxidative DNA damage. When A549 cells were pre-treated with the active metabolite I (2.5-5-10 μg/ml) for 10-30 min and then exposed to H 2O2(1-4 mM) for two additional hours at 37°C, 5% at CO2, the intracellular peroxide production, reflected by dichlorofluorescein (DCF) fluorescence, decreased in a concentration-dependent manner. Furthermore, using a comet assay as an indicator for oxidative DNA damage, it was found that the metabolite I prevented damage to cells exposed to short-term H2O2treatment. The data suggest that this compound is effective in preventing H2O2-induced oxidative stress and DNA damage in A549 cells. The underlying mechanisms involve the scavenging of intracellular reactive oxygen species (ROS)
Thymol and Thymus vulgaris extract protects human keratinocyte cell line (HaCaT) from UVA and UVB damage
Full text linkObjective: The aims of our study were to characterize ultraviolet (UV)A- and UVB-induced damages in a keratinocytes cell line (HaCaT), and to evaluate the protective capacities two plant-derivative compounds, namely Thymus vulgaris L leaf extract and thymol, its major component. A polyphenol rich diet has gained wide attention and it is now considered to be a protective agent for human skin, which can be over-exposed to environmental factors and in particular UV light.
Methods: Cells were pretreated for 1 h, in serum-free medium, with thymol (1 μg/ml) or Thymus vulgaris L (1.82 μg/ml) then exposed to different UVA (8-24 J/cm2) or UVB doses (0.016-0.72 J/cm2). Immediately after the UV exposure the intracellular redox status was evaluated by reactive oxygen species quantification and apoptotic events. Genotoxic aspects were evaluated 24 h after the end of irradiations using the alkaline comet assay and the immunostaining of phosphorylated H2AX histone protein (detected 1 h after the end of UV exposure).
Results: The pre-treatment of our experimental model with the two substances confirmed an antioxidant action and anti-apoptotic effect by reducing the cells percentage (sub-G1 phase). Furthermore, thymol and extract of Thymus vulgaris L were able to reduce genotoxic damage. The alkaline comet assay showed that the two substances were capable to decrease DNA damage. Also in this case, Thymus vulgaris L extract is more effective than thymol in decreasing genotoxicity markers.
Conclusions: Our results confirmed the more oxidant UVA and more genotoxic UVB effects. Regarding the protective effect of thymol and Thymus vulgaris L extract, data obtained proved their antioxidant and free-radical scavenging ability as known for phenolic (which our compounds belong to) and polyphenolic compounds. Thymol and mainly Thymus vulgaris L extract were also able to reduce the direct genotoxic damage
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