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1.
J Nutr ; 138(1): 49-53, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18156403

RESUMEN

Lycopene is a promising nutritional component for chemoprevention of prostate cancer (PCa). A possibly beneficial role of lycopene in patients diagnosed with benign prostate hyperplasia (BPH), who are at increased risk of developing PCa, has been suggested, although clinical data are lacking. Therefore, this pilot study aimed to investigate the effects of lycopene supplementation in elderly men diagnosed with BPH. A total of 40 patients with histologically proven BPH free of PCa were randomized to receive either lycopene at a dose of 15 mg/d or placebo for 6 mo. The effects of the intervention on carotenoid status, clinical diagnostic markers of prostate proliferation, and symptoms of the disease were assessed. The primary endpoint of the study was the inhibition or reduction of increased serum prostate-specific antigen (PSA) levels. The 6-mo lycopene supplementation decreased PSA levels in men (P < 0.05), whereas there was no change in the placebo group. The plasma lycopene concentration increased in the group taking lycopene (P < 0.0001) but other plasma carotenoids were not affected. Whereas progression of prostate enlargement occurred in the placebo group as assessed by trans-rectal ultrasonography (P < 0.05) and digital rectal examination (P < 0.01), the prostate did not enlarge in the lycopene group. Symptoms of the disease, as assessed via the International Prostate Symptom Score questionnaire, were improved in both groups with a significantly greater effect in men taking lycopene supplements. In conclusion, lycopene inhibited progression of BPH.


Asunto(s)
Carotenoides/uso terapéutico , Hiperplasia Prostática/tratamiento farmacológico , Anciano , Biomarcadores , Suplementos Dietéticos , Progresión de la Enfermedad , Método Doble Ciego , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor I del Crecimiento Similar a la Insulina , Licopeno , Masculino , Persona de Mediana Edad , Próstata/efectos de los fármacos , Próstata/patología , Antígeno Prostático Específico/sangre , Hiperplasia Prostática/sangre , Hiperplasia Prostática/patología
2.
Int J Food Sci Nutr ; 57(7-8): 546-55, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17162333

RESUMEN

The relative bioavailability of coenzyme Q10 (CoQ10) is markedly influenced by its delivery systems. The aim of this study was to compare four standard CoQ10 supplements available on the market with a novel solubilizate formulation of CoQ10 (Solu Q10). Pharmacokinetic parameters were assessed in 54 healthy volunteers after single and multiple intakes of 60 mg CoQ10 over a time period of 14 days. Solubilizates showed earlier flooding compared with oily dispersions and crystalline CoQ10, resulting in significantly elevated area under the curve between 0 and 4 h (P<0.01 solubilizates versus crystalline). The difference in the pharmacokinetic parameters of maximum plasma concentration, time to reach the peak plasma concentration and area under the curve between 0 and 12 h was not statistically significant between formulations. Long-term supplementation resulted in significantly higher plasma levels (P<0.01) for all formulations, with Solu Q10 performing best. Intracellular CoQ10 levels measured in buccal mucosa cells were increased (P<0.05) in response to supplementation when starting within the physiological range. In summary, solubilizates were clearly superior to oily dispersions and crystalline CoQ10 in their overall bioavailability, with the best absorption characteristics seen for the novel Solu Q10 solubilizate.


Asunto(s)
Mucosa Bucal/química , Ubiquinona/análogos & derivados , Adulto , Área Bajo la Curva , Disponibilidad Biológica , Coenzimas/análisis , Coenzimas/sangre , Coenzimas/farmacocinética , Suplementos Dietéticos , Formas de Dosificación , Esquema de Medicación , Humanos , Absorción Intestinal , Masculino , Solubilidad , Factores de Tiempo , Ubiquinona/análisis , Ubiquinona/sangre , Ubiquinona/farmacocinética
3.
J Nutr ; 136(5): 1287-93, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16614418

RESUMEN

Epidemiologic studies have repeatedly associated a high intake of lycopene and vitamin E with reduced prostate cancer risk. The present study examined the ability of the 2 compounds to reduce tumor growth and prostate-specific antigen (PSA) plasma levels in the PC-346C orthotopic mouse model of human prostate cancer. Three days after intraprostatic tumor injection, NMRI nu/nu mice were administered a daily oral dose of synthetic lycopene [5 or 50 mg/kg body weight (BW)], vitamin E in the form of alpha-tocopheryl acetate (5 or 50 mg/kg BW), a mixture of lycopene and vitamin E (5 mg/kg BW each), or vehicle. Intraprostatic tumor volume and plasma PSA concentrations were measured at regular intervals. Mice were killed when the tumor load exceeded 1000 mm(3) or on d 95 when the study was terminated. Prostate and liver were analyzed by HPLC for lycopene isomers and alpha- and gamma, delta-tocopherol concentrations. None of the single treatments significantly reduced tumor volume. In contrast, combined treatment with lycopene and vitamin E, at 5 mg/kg BW each, suppressed orthotopic growth of PC-346C prostate tumors by 73% at d 42 (P < 0.05) and increased median survival time by 40% from 47 to 66 d (P = 0.02). The PSA index (PSA:tumor volume ratio) did not differ between experimental groups, indicating that PSA levels were not selectively affected. Lycopene was detected only in mice supplemented with lycopene. As in humans, most tissue lycopene was in the cis-isomer conformation, whereas 77% trans-lycopene was used in the dosing material. Liver alpha-tocopherol concentrations were increased in mice supplemented with both 50 mg/kg (226%, P < 0.05) and 5 mg/kg vitamin E (41%, P < 0.05), whereas prostate alpha-tocopherol concentrations were increased only by the higher dose (83%, P < 0.05). Our data provide evidence that lycopene combined with vitamin E may inhibit the growth of prostate cancer and that PSA can serve as a biomarker of tumor response for this treatment regimen.


Asunto(s)
Anticarcinógenos/farmacología , Carotenoides/farmacología , Neoplasias de la Próstata/patología , Vitamina E/farmacología , Animales , Carotenoides/administración & dosificación , División Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Suplementos Dietéticos , Humanos , Licopeno , Masculino , Ratones , Ratones Desnudos , Trasplante Heterólogo , Vitamina E/administración & dosificación
5.
J Nutr ; 133(11): 3356-60, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14608044

RESUMEN

Lycopene has repeatedly been shown to inhibit the growth of human prostate cells in vitro. However, previous studies with lycopene have focused on cancer specimens, and it is still unclear whether this carotenoid affects the growth of normal human prostate cells as well. Therefore, we investigated the effects of lycopene on normal human prostate epithelial cells (PrEC) by treating them with synthetic all-E-lycopene (up to 5 micromol/L) and assessing proliferation via [3H]thymidine incorporation. The effects of lycopene on cell cycle progression were investigated via flow cytometry. To elucidate whether lycopene modulates cyclins involved in cell cycle progression, protein expressions of cyclins D1 and E were analyzed. The results show that lycopene significantly inhibited the growth of PrEC in a dose-dependent fashion. Flow cytometry revealed a significant cell cycle arrest in the G0/G1 phase. This effect was confirmed by inhibition of cyclin D1 protein expression, whereas cyclin E levels remained unchanged. The results demonstrate that lycopene inhibits growth of nonneoplastic PrEC in vitro. We hypothesize that lycopene might likewise inhibit the growth of prostatic epithelial cells in vivo. This might have an effect on prostate development and/or on enlargement of prostate tissue as found in benign prostate hyperplasia, a potential precursor of prostate cancer.


Asunto(s)
Antioxidantes/farmacología , Carotenoides/farmacología , Células Epiteliales/citología , Próstata/citología , Transporte Biológico , Carotenoides/aislamiento & purificación , Carotenoides/farmacocinética , División Celular/efectos de los fármacos , Células Cultivadas , Células Epiteliales/efectos de los fármacos , Humanos , Cinética , Licopeno , Masculino
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