Aim： To investigate whether oral treatment with D-004, a lipid extract of the Cuban royal palm fruit, produces antioxidant effects in the prostate tissue of normal and testosterone （T）-treated rats. Methods： In ou...Aim： To investigate whether oral treatment with D-004, a lipid extract of the Cuban royal palm fruit, produces antioxidant effects in the prostate tissue of normal and testosterone （T）-treated rats. Methods： In our first experiment, normal rats were distributed into five groups： one group treated with the vehicle and four groups treated with D-004 （100, 200, 400 or 800 mg/kg）. In our second experiment, rats were randomized into five groups： a negative control group and four T-injected groups. The latter were comprised of a positive control group treated with the vehicle, and three groups treated with D-004 （200, 400 or 800 mg/kg）. Results： In normal rats, D-004 （100-800 mg/kg） inhibited significantly and dose-dependently iron-initiated malondialdehyde （MDA） accumulation in prostate homogenates （35.7%-80.0%） vs. the controls. D-004 （200-800 mg/kg） significantly reduced baseline MDA and carbonyl groups in prostate homogenates of normal rats to approximately 80% and 50%, respectively, and totally （100%） in T-treated rats. Conclusion： Oral treatment with D-004 reduced MDA and carbonyl groups dose-dependently and markedly in normal and T-injected rats. These findings show that D-004 given at doses effective to prevent prostate hyperplasia also produces antioxidant effects in the prostate tissue.展开更多
The aim of thisstudy was to conduct a randomized, double-blind and placebo-controlled study to investigate the effects of D-004, a lipid extract of the Roystonea regia fruit that prevents testosterone- and phenylepine...The aim of thisstudy was to conduct a randomized, double-blind and placebo-controlled study to investigate the effects of D-004, a lipid extract of the Roystonea regia fruit that prevents testosterone- and phenylepinephrine- induced prostate hyperplasia in rodents, on plasma oxidative markers in healthy men. We enrolled male volunteers （20-55 years） in good health and without lower urinary tract symptoms. Thirty-four eligible participants were randomized to placebo or D-004 （320 mg） capsules administered daily for 6 weeks. An interim check-up and a final visit were conducted after 3 and 6 weeks of therapy, respectively. Physical examinations were performed at each visit, and laboratory tests were performed at baseline and at treatment completion. Oxidative variables included plasma malondialdehyde （MDA）, total hydroxyperoxides （TOH）, sulphydryl （SH） groups and total antioxidant status （TAS）. We assessed treatment compliance and addressed adverse experiences （AEs） at weeks 3 and 6. At week 6, with D-004, the mean reductions of plasma MDA （26.7%）, TOH （18.8%） and SH groups （31.6%）, and the mean increase of TAS （35.3%） were significantly different from those of placebo （P 〈 0.001 for plasma TAS, P 〈 0.0001 for all other comparisons）. D-004 did not differ from the placebo in safety indicators. There were two withdrawals （both in the D-004 group）, with one due to dyspepsia （the only AE during the trial）. In conclusion, D-004 displayed antioxidant effects on plasma oxidative markers in healthy men, which was consistent with findings from laboratory experimental studies.展开更多
Royal palm tree peroxidase (RPTP) has been isolated to homogeneity from leaves of Roystonea regia palm trees. The enzyme purification steps included homogenization, (NH4)SO4 precipitation, extraction of palm leaf colo...Royal palm tree peroxidase (RPTP) has been isolated to homogeneity from leaves of Roystonea regia palm trees. The enzyme purification steps included homogenization, (NH4)SO4 precipitation, extraction of palm leaf colored compounds and consecutive chromatography on Phenyl-Sepharose, TSK-Gel DEAE-5PW and Superdex-200. The novel peroxidase was characterized as having a molecular weight of 48.2 ± 3.0 kDa and an isoelectric point pI 5.4 ± 0.1. The enzyme forms dimers in solution with approximate molecular weight of 92 ± 2 kDa. Here we investigated the steady-state kinetic mechanism of the H2O2-supported oxidation of different organic substrates by RPTP. The results of the analysis of the initial rates vs. H2O2 and reducing substrate concentrations were seen to be consistent with a substrate-inhibited Ping-Pong Bi-Bi reaction mechanism. The phenomenological approach used expresses the peroxidase Ping-Pong mechanism in the form of the Michaelis-Menten equation and affords an interpretation of the effects in terms of the kinetic parameters KmH2O2, KmAH2, kcat, KSIH2O2, KSIAH2 and of the microscopic rate constants k1 and k3 of the shared three-step peroxidase catalytic cycle. Furthermore, the concentration and time-dependences and the mechanism of the suicide inactivation of RPTP by hydrogen peroxide were studied kinetically with guaiacol as co-substrate. The turnover number (r) of H2O2 required to complete the inactivation of the enzyme was 2154 ± 100 and the apparent rate constants of catalysis 185 s–1 and 18 s–1.展开更多
文摘Aim： To investigate whether oral treatment with D-004, a lipid extract of the Cuban royal palm fruit, produces antioxidant effects in the prostate tissue of normal and testosterone （T）-treated rats. Methods： In our first experiment, normal rats were distributed into five groups： one group treated with the vehicle and four groups treated with D-004 （100, 200, 400 or 800 mg/kg）. In our second experiment, rats were randomized into five groups： a negative control group and four T-injected groups. The latter were comprised of a positive control group treated with the vehicle, and three groups treated with D-004 （200, 400 or 800 mg/kg）. Results： In normal rats, D-004 （100-800 mg/kg） inhibited significantly and dose-dependently iron-initiated malondialdehyde （MDA） accumulation in prostate homogenates （35.7%-80.0%） vs. the controls. D-004 （200-800 mg/kg） significantly reduced baseline MDA and carbonyl groups in prostate homogenates of normal rats to approximately 80% and 50%, respectively, and totally （100%） in T-treated rats. Conclusion： Oral treatment with D-004 reduced MDA and carbonyl groups dose-dependently and markedly in normal and T-injected rats. These findings show that D-004 given at doses effective to prevent prostate hyperplasia also produces antioxidant effects in the prostate tissue.
文摘The aim of thisstudy was to conduct a randomized, double-blind and placebo-controlled study to investigate the effects of D-004, a lipid extract of the Roystonea regia fruit that prevents testosterone- and phenylepinephrine- induced prostate hyperplasia in rodents, on plasma oxidative markers in healthy men. We enrolled male volunteers （20-55 years） in good health and without lower urinary tract symptoms. Thirty-four eligible participants were randomized to placebo or D-004 （320 mg） capsules administered daily for 6 weeks. An interim check-up and a final visit were conducted after 3 and 6 weeks of therapy, respectively. Physical examinations were performed at each visit, and laboratory tests were performed at baseline and at treatment completion. Oxidative variables included plasma malondialdehyde （MDA）, total hydroxyperoxides （TOH）, sulphydryl （SH） groups and total antioxidant status （TAS）. We assessed treatment compliance and addressed adverse experiences （AEs） at weeks 3 and 6. At week 6, with D-004, the mean reductions of plasma MDA （26.7%）, TOH （18.8%） and SH groups （31.6%）, and the mean increase of TAS （35.3%） were significantly different from those of placebo （P 〈 0.001 for plasma TAS, P 〈 0.0001 for all other comparisons）. D-004 did not differ from the placebo in safety indicators. There were two withdrawals （both in the D-004 group）, with one due to dyspepsia （the only AE during the trial）. In conclusion, D-004 displayed antioxidant effects on plasma oxidative markers in healthy men, which was consistent with findings from laboratory experimental studies.
文摘Royal palm tree peroxidase (RPTP) has been isolated to homogeneity from leaves of Roystonea regia palm trees. The enzyme purification steps included homogenization, (NH4)SO4 precipitation, extraction of palm leaf colored compounds and consecutive chromatography on Phenyl-Sepharose, TSK-Gel DEAE-5PW and Superdex-200. The novel peroxidase was characterized as having a molecular weight of 48.2 ± 3.0 kDa and an isoelectric point pI 5.4 ± 0.1. The enzyme forms dimers in solution with approximate molecular weight of 92 ± 2 kDa. Here we investigated the steady-state kinetic mechanism of the H2O2-supported oxidation of different organic substrates by RPTP. The results of the analysis of the initial rates vs. H2O2 and reducing substrate concentrations were seen to be consistent with a substrate-inhibited Ping-Pong Bi-Bi reaction mechanism. The phenomenological approach used expresses the peroxidase Ping-Pong mechanism in the form of the Michaelis-Menten equation and affords an interpretation of the effects in terms of the kinetic parameters KmH2O2, KmAH2, kcat, KSIH2O2, KSIAH2 and of the microscopic rate constants k1 and k3 of the shared three-step peroxidase catalytic cycle. Furthermore, the concentration and time-dependences and the mechanism of the suicide inactivation of RPTP by hydrogen peroxide were studied kinetically with guaiacol as co-substrate. The turnover number (r) of H2O2 required to complete the inactivation of the enzyme was 2154 ± 100 and the apparent rate constants of catalysis 185 s–1 and 18 s–1.
