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Josep Lluís Torres - One of the best experts on this subject based on the ideXlab platform.
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Hamamelitannin from Witch Hazel (Hamamelis virginiana) Displays Specific Cytotoxic Activity against Colon Cancer Cells
Journal of Natural Products, 2012Co-Authors: Susana Sánchez-tena, Anna Carreras, M. Luisa Mateos-martín, Noelia Costoya, Maria Luisa Fernandez-cachon, Josep Lluís Torres, María J. Núñez, Mary Pat Moyer, Marta CascanteAbstract:Hamamelis virginiana (witch Hazel) bark is a rich source of condensed and hydrolyzable tannins reported to exert a protective action against colon cancer. The present study characterizes different witch Hazel tannins as selective cytotoxic agents against colon cancer. To cover the structural diversity of the tannins that occur in H. virginiana bark, the hydrolyzable tannins, hamamelitannin and pentagalloylglucose, together with a proanthocyanidin-rich fraction (F800H4) were selected for the study. Treatment with these compounds reduced tumor viability and induced apoptosis, necrosis, and S-phase arrest in the cell cycle of HT29 cells, with hamamelitannin being the most efficient. Owing to polyphenol-mediated H2O2 formation in the incubation media, the antiproliferative effect was determined in the presence and absence of catalase to rule out any such interference. The presence of catalase significantly changed the IC50 only for F800H4. Furthermore, at concentrations that inhibit the growth of HT29 cells b...
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witch Hazel hamamelis virginiana fractions and the importance of gallate moieties electron transfer capacities in their antitumoral properties
Journal of Agricultural and Food Chemistry, 2008Co-Authors: Daneida Lizarraga, Sonia Touriño, Josep Lluís Torres, Jacob J Briede, L.m. Maas, Josep J Centelles, Fernando J Reyeszurita, Theo M De Kok, Joost H M Van Delft, Marta CascanteAbstract:Witch Hazel (Hamamelis virginia) extracts are used in traditional medicine. They are particularly rich in gallate esters included in proanthocyanidins, hydrolyzable tannins (galloylated sugars), and methyl gallate. This study examines the response of human colon cancer cells to treatment with fractions obtained from a witch Hazel polyphenolic extract. The results are compared with those obtained previously with homologous fractions from grape (less galloylated) and pine (nongalloylated). Witch Hazel fractions were the most efficient in inhibiting cell proliferation in HT29 and HCT116 human colon cancer cell lines, which clearly shows that the more galloylated the fractions, the more effective they were at inhibiting proliferation of colon cancer cells. Witch Hazel fractions were, in addition, more potent in arresting the cell cycle at the S phase and inducing apoptosis; they also induced a significant percentage of necrosis. Interestingly, the apoptosis and cell cycle arrest effects induced were proportional to their galloylation. Moreover, witch Hazel fractions with a high degree of galloylation were also the most effective as scavengers of both hydroxyl and superoxide radicals and in protecting against DNA damage triggered by the hydroxyl radical system. These findings provide a better understanding of the structure-bioactivity relationships of polyphenolics, which should be of assistance in choosing an appropriate source and preparing a rational design for formulations of plant polyphenols in nutritional supplements.
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Highly Galloylated Tannin Fractions from Witch Hazel (Hamamelis virginiana) Bark: Electron Transfer Capacity, In Vitro Antioxidant Activity, and Effects on Skin-Related Cells
Chemical Research in Toxicology, 2008Co-Authors: Sonia Touriño, Daneida Lizarraga, Anna Carreras, Sonia Lorenzo, Vanessa Ugartondo, Luis Julia, María Pilar Vinardell, Montserrat Mitjans, Marta Cascante, Josep Lluís TorresAbstract:Witch Hazel (Hammamelis virginiana) bark is a rich source of both condensed and hydrolizable oligomeric tannins. From a polyphenolic extract soluble in both ethyl acetate and water, we have generated fractions rich in pyrogallol-containing polyphenols (proanthocyanidins, gallotannins, and gallates). The mixtures were highly active as free radical scavengers against ABTS, DPPH (hydrogen donation and electron transfer), and HNTTM (electron transfer). They were also able to reduce the newly introduced TNPTM radical, meaning that they included some highly reactive components. Witch Hazel phenolics protected red blood cells from free radical-induced hemolysis and were mildly cytotoxic to 3T3 fibroblasts and HaCat keratinocytes. They also inhibited the proliferation of tumoral SK-Mel 28 melanoma cells at lower concentrations than grape and pine procyanidins. The high content in pyrogallol moieties may be behind the effect of witch Hazel phenolics on skin cells. Because the most cytotoxic and antiproliferative m...
Marta Cascante - One of the best experts on this subject based on the ideXlab platform.
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Hamamelitannin from Witch Hazel (Hamamelis virginiana) Displays Specific Cytotoxic Activity against Colon Cancer Cells
Journal of Natural Products, 2012Co-Authors: Susana Sánchez-tena, Anna Carreras, M. Luisa Mateos-martín, Noelia Costoya, Maria Luisa Fernandez-cachon, Josep Lluís Torres, María J. Núñez, Mary Pat Moyer, Marta CascanteAbstract:Hamamelis virginiana (witch Hazel) bark is a rich source of condensed and hydrolyzable tannins reported to exert a protective action against colon cancer. The present study characterizes different witch Hazel tannins as selective cytotoxic agents against colon cancer. To cover the structural diversity of the tannins that occur in H. virginiana bark, the hydrolyzable tannins, hamamelitannin and pentagalloylglucose, together with a proanthocyanidin-rich fraction (F800H4) were selected for the study. Treatment with these compounds reduced tumor viability and induced apoptosis, necrosis, and S-phase arrest in the cell cycle of HT29 cells, with hamamelitannin being the most efficient. Owing to polyphenol-mediated H2O2 formation in the incubation media, the antiproliferative effect was determined in the presence and absence of catalase to rule out any such interference. The presence of catalase significantly changed the IC50 only for F800H4. Furthermore, at concentrations that inhibit the growth of HT29 cells b...
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witch Hazel hamamelis virginiana fractions and the importance of gallate moieties electron transfer capacities in their antitumoral properties
Journal of Agricultural and Food Chemistry, 2008Co-Authors: Daneida Lizarraga, Sonia Touriño, Josep Lluís Torres, Jacob J Briede, L.m. Maas, Josep J Centelles, Fernando J Reyeszurita, Theo M De Kok, Joost H M Van Delft, Marta CascanteAbstract:Witch Hazel (Hamamelis virginia) extracts are used in traditional medicine. They are particularly rich in gallate esters included in proanthocyanidins, hydrolyzable tannins (galloylated sugars), and methyl gallate. This study examines the response of human colon cancer cells to treatment with fractions obtained from a witch Hazel polyphenolic extract. The results are compared with those obtained previously with homologous fractions from grape (less galloylated) and pine (nongalloylated). Witch Hazel fractions were the most efficient in inhibiting cell proliferation in HT29 and HCT116 human colon cancer cell lines, which clearly shows that the more galloylated the fractions, the more effective they were at inhibiting proliferation of colon cancer cells. Witch Hazel fractions were, in addition, more potent in arresting the cell cycle at the S phase and inducing apoptosis; they also induced a significant percentage of necrosis. Interestingly, the apoptosis and cell cycle arrest effects induced were proportional to their galloylation. Moreover, witch Hazel fractions with a high degree of galloylation were also the most effective as scavengers of both hydroxyl and superoxide radicals and in protecting against DNA damage triggered by the hydroxyl radical system. These findings provide a better understanding of the structure-bioactivity relationships of polyphenolics, which should be of assistance in choosing an appropriate source and preparing a rational design for formulations of plant polyphenols in nutritional supplements.
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Highly Galloylated Tannin Fractions from Witch Hazel (Hamamelis virginiana) Bark: Electron Transfer Capacity, In Vitro Antioxidant Activity, and Effects on Skin-Related Cells
Chemical Research in Toxicology, 2008Co-Authors: Sonia Touriño, Daneida Lizarraga, Anna Carreras, Sonia Lorenzo, Vanessa Ugartondo, Luis Julia, María Pilar Vinardell, Montserrat Mitjans, Marta Cascante, Josep Lluís TorresAbstract:Witch Hazel (Hammamelis virginiana) bark is a rich source of both condensed and hydrolizable oligomeric tannins. From a polyphenolic extract soluble in both ethyl acetate and water, we have generated fractions rich in pyrogallol-containing polyphenols (proanthocyanidins, gallotannins, and gallates). The mixtures were highly active as free radical scavengers against ABTS, DPPH (hydrogen donation and electron transfer), and HNTTM (electron transfer). They were also able to reduce the newly introduced TNPTM radical, meaning that they included some highly reactive components. Witch Hazel phenolics protected red blood cells from free radical-induced hemolysis and were mildly cytotoxic to 3T3 fibroblasts and HaCat keratinocytes. They also inhibited the proliferation of tumoral SK-Mel 28 melanoma cells at lower concentrations than grape and pine procyanidins. The high content in pyrogallol moieties may be behind the effect of witch Hazel phenolics on skin cells. Because the most cytotoxic and antiproliferative m...
Angela Schwarm - One of the best experts on this subject based on the ideXlab platform.
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increasing the proportion of Hazel leaves in the diet of dairy cows reduced methane yield and excretion of nitrogen in volatile form but not milk yield
Animal Feed Science and Technology, 2020Co-Authors: Melissa Terranova, Angela Schwarm, Lukas Eggerschwiler, Sylvia Ortmann, Marcus Clauss, Michael KreuzerAbstract:Abstract Various feeds for ruminants have been identified that help to mitigate the greenhouse gas methane. However, even when there has been success in suppressing absolute methane emissions, intake, digestibility, and performance often decline in parallel. Ideal dietary levels of effective feeds would reduce methane production without affecting performance-related variables. Such favorable associative effects have been demonstrated in vitro by combining a high-quality forage with plants rich in phenols. In the present study, the tannin-rich leaves of Hazel (Corylus avellana) gradually replaced (from 0 to 820 g/kg) a high-quality forage (dried alfalfa) in 20 types of experimental pellets fed to 20 mid-to-late lactating cows. Additionally, the cows were fed a mixed basal ration and some concentrate. The proportion of Hazel in the 20 complete diets ranged from 0 to 400 g/kg dry matter. After 14 days of adaptation, 8 days were used for intensive sampling of feces (including markers for determining digesta retention time), urine, and milk. In addition, cows stayed for 2 days in open-circuit respiration chambers. Hazel leaves reduced the feed intake only slightly. Digestibility declined and mean digesta retention time was prolonged with increasing Hazel proportion, likely due to the lower feeding value of the Hazel leaves compared to the alfalfa. As aimed for, there were no significant effects on energy-corrected milk yield, body energy, and body N retention with increasing Hazel intake, even though methane emission clearly declined in absolute term and per unit of digestible organic matter and tended to decrease per unit of energy corrected milk. In addition, increasing Hazel proportions strongly shifted N excretion from urinary (which declined from about 300 to 100 g/kg N intake) to fecal N. This could also be anticipated from the sharp decline in milk urea concentration (from about 30 to 10 mg/dL). In conclusion, Hazel leaves as a feed supplement for dairy cows showed a high palatability within 3 weeks of feeding in dairy cows and great potential to mitigate emissions of methane and nitrogen in volatile form at maintained production levels. No favorable associative dosage effects seem to exist when combining tannin-rich Hazel leaves with the high-quality forage alfalfa in a constant proportion to a mixed basal ration. However, the present study is one of the few, where it was possible to mitigate noxious emissions of dairy cows by feeding a tannin rich feed supplement without concomitant negative impact on the animal’s performance.
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effect of supplementation of pelleted Hazel corylus avellana leaves on blood antioxidant activity cellular immune response and heart beat parameters in sheep
Journal of Animal Science, 2019Co-Authors: Shaopu Wang, Katrin Giller, Edna Hillmann, Svenja Marquardt, Angela SchwarmAbstract:Hazel leaves (Corylus avellana) fed to sheep resulted in decreased methane emissions without negatively affecting feed intake and were found to have antioxidant properties in vitro. The objective of this study was to evaluate effects of Hazel leaves, rich in tannins, on blood antioxidant activity, cellular immune response, and heart beat parameters in sheep. Four experimental pellets were produced by mixing alfalfa and Hazel leaves in different proportions, including alfalfa alone as a control, 30% and 60% of Hazel leaves, the latter also with 3.8% polyethylene glycol (PEG). Six adult, nonpregnant, nonlactating female sheep (71 ± 5.7 kg of body weight) were allocated to 4 treatments in a 6 × 4 crossover design with four 18-d periods. The diet consisted of experimental pellets and ryegrass-dominated hay (ratio 80% to 20% in dry matter), resulting in Hazel leaf proportions of approximately 0%, 25%, and 50% in the total diet. Blood samples were collected at the end of each period to determine plasma total phenol concentration and markers of oxidative status as well as peripheral blood mononuclear cells (PBMC) activation and proliferation response in vitro. Heart rate (HR) and HR variability parameters were measured for 2 consecutive days in each period, during different activities (i.e., eating pellets or hay, or lying). Treatments were compared with multiple comparisons and contrast analysis was used to test for linear and quadratic relations. Compared with control, feeding a high dosage of Hazel leaves enhanced (P = 0.006) the plasma total antioxidant capacity, which linearly (P = 0.016) increased with increasing level of Hazel leaves in the diet. The total phenol concentration and activities of the antioxidant enzymes superoxide dismutase, catalase, and glutathione reductase in the plasma were not different (P ≥ 0.23) among the treatments; however, the latter slightly increased linearly (P = 0.047) with increasing Hazel leaves proportion. No differences were observed in the activation and proliferation of PBMC among treatments. The HR decreased linearly (P ≤ 0.009) during pellet eating and lying and the root mean square of successive differences of interbeat intervals (RMSSD) increased linearly (P = 0.037) when lying with increasing level of Hazel leaves in the diet. In conclusion, our findings indicate that Hazel leaves are a promising supplement to improve oxidative status with no effect on cellular immune response and cardiac stress level of sheep.
Sonia Touriño - One of the best experts on this subject based on the ideXlab platform.
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witch Hazel hamamelis virginiana fractions and the importance of gallate moieties electron transfer capacities in their antitumoral properties
Journal of Agricultural and Food Chemistry, 2008Co-Authors: Daneida Lizarraga, Sonia Touriño, Josep Lluís Torres, Jacob J Briede, L.m. Maas, Josep J Centelles, Fernando J Reyeszurita, Theo M De Kok, Joost H M Van Delft, Marta CascanteAbstract:Witch Hazel (Hamamelis virginia) extracts are used in traditional medicine. They are particularly rich in gallate esters included in proanthocyanidins, hydrolyzable tannins (galloylated sugars), and methyl gallate. This study examines the response of human colon cancer cells to treatment with fractions obtained from a witch Hazel polyphenolic extract. The results are compared with those obtained previously with homologous fractions from grape (less galloylated) and pine (nongalloylated). Witch Hazel fractions were the most efficient in inhibiting cell proliferation in HT29 and HCT116 human colon cancer cell lines, which clearly shows that the more galloylated the fractions, the more effective they were at inhibiting proliferation of colon cancer cells. Witch Hazel fractions were, in addition, more potent in arresting the cell cycle at the S phase and inducing apoptosis; they also induced a significant percentage of necrosis. Interestingly, the apoptosis and cell cycle arrest effects induced were proportional to their galloylation. Moreover, witch Hazel fractions with a high degree of galloylation were also the most effective as scavengers of both hydroxyl and superoxide radicals and in protecting against DNA damage triggered by the hydroxyl radical system. These findings provide a better understanding of the structure-bioactivity relationships of polyphenolics, which should be of assistance in choosing an appropriate source and preparing a rational design for formulations of plant polyphenols in nutritional supplements.
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Highly Galloylated Tannin Fractions from Witch Hazel (Hamamelis virginiana) Bark: Electron Transfer Capacity, In Vitro Antioxidant Activity, and Effects on Skin-Related Cells
Chemical Research in Toxicology, 2008Co-Authors: Sonia Touriño, Daneida Lizarraga, Anna Carreras, Sonia Lorenzo, Vanessa Ugartondo, Luis Julia, María Pilar Vinardell, Montserrat Mitjans, Marta Cascante, Josep Lluís TorresAbstract:Witch Hazel (Hammamelis virginiana) bark is a rich source of both condensed and hydrolizable oligomeric tannins. From a polyphenolic extract soluble in both ethyl acetate and water, we have generated fractions rich in pyrogallol-containing polyphenols (proanthocyanidins, gallotannins, and gallates). The mixtures were highly active as free radical scavengers against ABTS, DPPH (hydrogen donation and electron transfer), and HNTTM (electron transfer). They were also able to reduce the newly introduced TNPTM radical, meaning that they included some highly reactive components. Witch Hazel phenolics protected red blood cells from free radical-induced hemolysis and were mildly cytotoxic to 3T3 fibroblasts and HaCat keratinocytes. They also inhibited the proliferation of tumoral SK-Mel 28 melanoma cells at lower concentrations than grape and pine procyanidins. The high content in pyrogallol moieties may be behind the effect of witch Hazel phenolics on skin cells. Because the most cytotoxic and antiproliferative m...
Daneida Lizarraga - One of the best experts on this subject based on the ideXlab platform.
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witch Hazel hamamelis virginiana fractions and the importance of gallate moieties electron transfer capacities in their antitumoral properties
Journal of Agricultural and Food Chemistry, 2008Co-Authors: Daneida Lizarraga, Sonia Touriño, Josep Lluís Torres, Jacob J Briede, L.m. Maas, Josep J Centelles, Fernando J Reyeszurita, Theo M De Kok, Joost H M Van Delft, Marta CascanteAbstract:Witch Hazel (Hamamelis virginia) extracts are used in traditional medicine. They are particularly rich in gallate esters included in proanthocyanidins, hydrolyzable tannins (galloylated sugars), and methyl gallate. This study examines the response of human colon cancer cells to treatment with fractions obtained from a witch Hazel polyphenolic extract. The results are compared with those obtained previously with homologous fractions from grape (less galloylated) and pine (nongalloylated). Witch Hazel fractions were the most efficient in inhibiting cell proliferation in HT29 and HCT116 human colon cancer cell lines, which clearly shows that the more galloylated the fractions, the more effective they were at inhibiting proliferation of colon cancer cells. Witch Hazel fractions were, in addition, more potent in arresting the cell cycle at the S phase and inducing apoptosis; they also induced a significant percentage of necrosis. Interestingly, the apoptosis and cell cycle arrest effects induced were proportional to their galloylation. Moreover, witch Hazel fractions with a high degree of galloylation were also the most effective as scavengers of both hydroxyl and superoxide radicals and in protecting against DNA damage triggered by the hydroxyl radical system. These findings provide a better understanding of the structure-bioactivity relationships of polyphenolics, which should be of assistance in choosing an appropriate source and preparing a rational design for formulations of plant polyphenols in nutritional supplements.
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Highly Galloylated Tannin Fractions from Witch Hazel (Hamamelis virginiana) Bark: Electron Transfer Capacity, In Vitro Antioxidant Activity, and Effects on Skin-Related Cells
Chemical Research in Toxicology, 2008Co-Authors: Sonia Touriño, Daneida Lizarraga, Anna Carreras, Sonia Lorenzo, Vanessa Ugartondo, Luis Julia, María Pilar Vinardell, Montserrat Mitjans, Marta Cascante, Josep Lluís TorresAbstract:Witch Hazel (Hammamelis virginiana) bark is a rich source of both condensed and hydrolizable oligomeric tannins. From a polyphenolic extract soluble in both ethyl acetate and water, we have generated fractions rich in pyrogallol-containing polyphenols (proanthocyanidins, gallotannins, and gallates). The mixtures were highly active as free radical scavengers against ABTS, DPPH (hydrogen donation and electron transfer), and HNTTM (electron transfer). They were also able to reduce the newly introduced TNPTM radical, meaning that they included some highly reactive components. Witch Hazel phenolics protected red blood cells from free radical-induced hemolysis and were mildly cytotoxic to 3T3 fibroblasts and HaCat keratinocytes. They also inhibited the proliferation of tumoral SK-Mel 28 melanoma cells at lower concentrations than grape and pine procyanidins. The high content in pyrogallol moieties may be behind the effect of witch Hazel phenolics on skin cells. Because the most cytotoxic and antiproliferative m...
