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Wine Lees: A possible agent in the epigenetic therapy against hepatocarcinogenesis
S98
Abstracts / Toxicology Letters 258S (2016) S62–S324
P03-020 Effects of pycnogenol on cisplatin cytotoxicity in HeLa cells M. Becit 1,∗ , S. Aydin 1 , A.A. Basaran 2 , N. Basaran 1 1
Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Hacettepe University, 06100 Ankara, Turkey 2 Department of Pharmacognosy, Faculty of Pharmacy, Hacettepe University, 06100 Ankara, Turkey
Phenolic compounds are protective agents against oxidative stress-related diseases. They can play an important role in the preventing DNA damage, regulating DNA repair mechanisms, inhibiting carcinogenesis. Pycnogenol (PYC), natural dried extract obtained from the bark of Pinus pinaster, is commonly consumed as a dietary food supplement due to its strong antioxidant activity. The anticancer effect of PYC has been the subject of many researches. It is believed that some natural compounds might reduce the development of cancer. However, there are not sufficient studies on the interactions between antineoplastic drugs and natural phenolic compounds. Cisplatin is an anti-cancer chemotherapy drug to treat many types of cancer including esophageal, lung, breast, ovarian, bladder, cervical, and prostate cancers. This study was focused on the effects of pycnogenol on the cytotoxicity of cisplatin in HeLa cells using Thiazolyl Blue Tetrazolium Blue (MTT) assay. The IC50 doses of cisplatin in HeLa cells for 24 h and 48 h were found to be 22.4 M and 12.3 M, respectively. The IC50 doses of PYC in HeLa cells for 24 h and 48 h were found to be 502 M and 409 M, respectively. PYC significantly increased the cytotoxicity of cisplatin in HeLa cells at all studied concentrations of 15.6–500 M for 24 h and 250–500 M for 48 h. Our results suggest that PYC might contribute to the anticancer effect of cisplatin in cervical carcinoma, but further in vitro studies with other cancer cell lines as well as in vivo studies are needed. http://dx.doi.org/10.1016/j.toxlet.2016.06.1421 P03-021 Wine Lees: A possible agent in the epigenetic therapy against hepatocarcinogenesis Z. Fernández-Bedmar 1 , J. Anter 1 , S. Guil-Luna 2 , J. de las Mulas 2 , Y. Millán 2 , M. Luque de Castro 3 , P. Delgado de la Torre 3 , M. Mateo-Fernández 1 , T. Merinas-Amo 1,∗ , Á. Alonso-Moraga 1 1
Department of Genetics, Gregor Mendel Building, Faculty of Science, University of Córdoba, Córdoba, Spain 2 Department of Comparative Pathology, Veterinary Medicine Faculty, University of Córdoba, Córdoba, Spain 3 Department of Analytical Chemistry, University of Córdoba, Córdoba, Spain Nowadays there is an urgent need to find new strategies to reduce the incidence of hepatocellular carcinoma. Selectivefocused diets are considered a preventive strategy for this cancer. Grapes polyphenols exert beneficial effects on degenerative diseases. Wine lees are sediments consisting of residues of yeast cells, skin and grape seeds. These sediments provide certain organoleptic properties and improve the physicochemical stability of the wine. However, their role in the wine anticarcinogenic effects is yet unknown. In order to study the anticarcinogenic effects of wine lees, a diethylnitrosamine (DEN) induced rat hepatocarcinogenesis bioassay was followed. The global methylation patterns using the Alu-M2 repetitive element as a global methylation marker and the concurrent macroscopic and histological effects induced by these
sediments and diethylnitrosamine have been evaluated. The results showed a hipermethylation of the Alu-M2 repetitive sequence in the rat genome by DEN. The rats co-treated with DEN and wine lees reduced the methylation level (hipomethylation) of the repetitive sequence at all concentrations of white lees (1000, 2000 and 4000 ppm) and at the lowest concentration of red lees (1000 ppm). An improvement of the hepatocellular architecture and a reduction of the mitotic index by white (1000 and 4000 ppm) and red (1000 ppm) lees respect to the DEN-control group was observed at histopathological level. In conclusion, these findings suggest that the wine lees could be considered as a possible epigenetic therapy option in the treatment of the hepatocellular carcinoma. http://dx.doi.org/10.1016/j.toxlet.2016.06.1422 P03-022 n-3 Polyunsaturated fatty acids alter benzo[a]pyrene toxicity in a model of human colon cancer cells Z. Tylichova 1,∗ , J. Neˇca 2 , M. Machala 2 , J. Topinka 3 , A. Milcová 3 , J. Hofmanová 1 , A. Kozubík 1 , J. Vondráˇcek 1 1
Institute of Biophysics, Czech Academy of Sciences, Brno, Czech Republic 2 Veterinary Research Institute, Brno, Czech Republic 3 Institute of Experimental Medicine ASCR, Prague, Czech Republic Diet rich in n-3 polyunsaturated fatty acids (PUFAs) has been proposed to provide anti-tumor protection and several epidemiologic studies have suggested a decrease in colorectal cancer risk among individuals consuming diets high in PUFAs. The primary aim of this study was to investigate the effect of two major PUFAs, eicosapentaenoic acid (EPA, 20:5) and docosahexaenoic acid (DHA, 22:6), on genotoxic effects of benzo[a]pyrene (BaP), a carcinogenic polycyclic aromatic hydrocarbon that can be found at significant levels in processed food. We hypothesized that addition of physiological dose of EPA and DHA might interfere with BaP metabolism/bioactivation and/or alter its toxic effects. Using a model of human colon cells – colon carcinoma HCT-116 cell line – we analyzed the impact of PUFAs on BaP metabolism and induction of DNA damage. HCT-116 cells are able to metabolize and bioactivate BaP, via the cytochrome P450 family 1 (CYP1) enzymes, which in turn leads to formation of covalent DNA adducts. We observed that cells treated with either EPA or DHA exhibited significantly lower CYP1 activity that was determined as ethoxyresorufin-Odeethylase activity. Application of both PUFAs also significantly reduced formation of covalent DNA adducts in HCT-116 cells, as determined by 32P-postlabeling, or further genotoxic events. However, only EPA decreased the formation of major BaP metabolites, while DHA had no apparent effect on their levels. Thus both PUFAs may limit bioactivation and genotoxic effects of BaP in colon epithelial cells; however, they may act through different mechanisms. Supported by the Czech Science Foundation, project no. 1309766S. http://dx.doi.org/10.1016/j.toxlet.2016.06.1423
Abstracts / Toxicology Letters 258S (2016) S62–S324
P03-020 Effects of pycnogenol on cisplatin cytotoxicity in HeLa cells M. Becit 1,∗ , S. Aydin 1 , A.A. Basaran 2 , N. Basaran 1 1
Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Hacettepe University, 06100 Ankara, Turkey 2 Department of Pharmacognosy, Faculty of Pharmacy, Hacettepe University, 06100 Ankara, Turkey
Phenolic compounds are protective agents against oxidative stress-related diseases. They can play an important role in the preventing DNA damage, regulating DNA repair mechanisms, inhibiting carcinogenesis. Pycnogenol (PYC), natural dried extract obtained from the bark of Pinus pinaster, is commonly consumed as a dietary food supplement due to its strong antioxidant activity. The anticancer effect of PYC has been the subject of many researches. It is believed that some natural compounds might reduce the development of cancer. However, there are not sufficient studies on the interactions between antineoplastic drugs and natural phenolic compounds. Cisplatin is an anti-cancer chemotherapy drug to treat many types of cancer including esophageal, lung, breast, ovarian, bladder, cervical, and prostate cancers. This study was focused on the effects of pycnogenol on the cytotoxicity of cisplatin in HeLa cells using Thiazolyl Blue Tetrazolium Blue (MTT) assay. The IC50 doses of cisplatin in HeLa cells for 24 h and 48 h were found to be 22.4 M and 12.3 M, respectively. The IC50 doses of PYC in HeLa cells for 24 h and 48 h were found to be 502 M and 409 M, respectively. PYC significantly increased the cytotoxicity of cisplatin in HeLa cells at all studied concentrations of 15.6–500 M for 24 h and 250–500 M for 48 h. Our results suggest that PYC might contribute to the anticancer effect of cisplatin in cervical carcinoma, but further in vitro studies with other cancer cell lines as well as in vivo studies are needed. http://dx.doi.org/10.1016/j.toxlet.2016.06.1421 P03-021 Wine Lees: A possible agent in the epigenetic therapy against hepatocarcinogenesis Z. Fernández-Bedmar 1 , J. Anter 1 , S. Guil-Luna 2 , J. de las Mulas 2 , Y. Millán 2 , M. Luque de Castro 3 , P. Delgado de la Torre 3 , M. Mateo-Fernández 1 , T. Merinas-Amo 1,∗ , Á. Alonso-Moraga 1 1
Department of Genetics, Gregor Mendel Building, Faculty of Science, University of Córdoba, Córdoba, Spain 2 Department of Comparative Pathology, Veterinary Medicine Faculty, University of Córdoba, Córdoba, Spain 3 Department of Analytical Chemistry, University of Córdoba, Córdoba, Spain Nowadays there is an urgent need to find new strategies to reduce the incidence of hepatocellular carcinoma. Selectivefocused diets are considered a preventive strategy for this cancer. Grapes polyphenols exert beneficial effects on degenerative diseases. Wine lees are sediments consisting of residues of yeast cells, skin and grape seeds. These sediments provide certain organoleptic properties and improve the physicochemical stability of the wine. However, their role in the wine anticarcinogenic effects is yet unknown. In order to study the anticarcinogenic effects of wine lees, a diethylnitrosamine (DEN) induced rat hepatocarcinogenesis bioassay was followed. The global methylation patterns using the Alu-M2 repetitive element as a global methylation marker and the concurrent macroscopic and histological effects induced by these
sediments and diethylnitrosamine have been evaluated. The results showed a hipermethylation of the Alu-M2 repetitive sequence in the rat genome by DEN. The rats co-treated with DEN and wine lees reduced the methylation level (hipomethylation) of the repetitive sequence at all concentrations of white lees (1000, 2000 and 4000 ppm) and at the lowest concentration of red lees (1000 ppm). An improvement of the hepatocellular architecture and a reduction of the mitotic index by white (1000 and 4000 ppm) and red (1000 ppm) lees respect to the DEN-control group was observed at histopathological level. In conclusion, these findings suggest that the wine lees could be considered as a possible epigenetic therapy option in the treatment of the hepatocellular carcinoma. http://dx.doi.org/10.1016/j.toxlet.2016.06.1422 P03-022 n-3 Polyunsaturated fatty acids alter benzo[a]pyrene toxicity in a model of human colon cancer cells Z. Tylichova 1,∗ , J. Neˇca 2 , M. Machala 2 , J. Topinka 3 , A. Milcová 3 , J. Hofmanová 1 , A. Kozubík 1 , J. Vondráˇcek 1 1
Institute of Biophysics, Czech Academy of Sciences, Brno, Czech Republic 2 Veterinary Research Institute, Brno, Czech Republic 3 Institute of Experimental Medicine ASCR, Prague, Czech Republic Diet rich in n-3 polyunsaturated fatty acids (PUFAs) has been proposed to provide anti-tumor protection and several epidemiologic studies have suggested a decrease in colorectal cancer risk among individuals consuming diets high in PUFAs. The primary aim of this study was to investigate the effect of two major PUFAs, eicosapentaenoic acid (EPA, 20:5) and docosahexaenoic acid (DHA, 22:6), on genotoxic effects of benzo[a]pyrene (BaP), a carcinogenic polycyclic aromatic hydrocarbon that can be found at significant levels in processed food. We hypothesized that addition of physiological dose of EPA and DHA might interfere with BaP metabolism/bioactivation and/or alter its toxic effects. Using a model of human colon cells – colon carcinoma HCT-116 cell line – we analyzed the impact of PUFAs on BaP metabolism and induction of DNA damage. HCT-116 cells are able to metabolize and bioactivate BaP, via the cytochrome P450 family 1 (CYP1) enzymes, which in turn leads to formation of covalent DNA adducts. We observed that cells treated with either EPA or DHA exhibited significantly lower CYP1 activity that was determined as ethoxyresorufin-Odeethylase activity. Application of both PUFAs also significantly reduced formation of covalent DNA adducts in HCT-116 cells, as determined by 32P-postlabeling, or further genotoxic events. However, only EPA decreased the formation of major BaP metabolites, while DHA had no apparent effect on their levels. Thus both PUFAs may limit bioactivation and genotoxic effects of BaP in colon epithelial cells; however, they may act through different mechanisms. Supported by the Czech Science Foundation, project no. 1309766S. http://dx.doi.org/10.1016/j.toxlet.2016.06.1423