isoflavone ; prostate cancer ; prostate specific antigen (PSA) ; antioxidant status ; lipid profiles
Abstract
Soy foods are a unique dietary source of isoflavones, which have effects relevant to prostate cancer prevention. The present study determines the effects of a short-term isoflavone supplement on serum PSA (prostate specific antigen), lipid profile, antioxidant status, and immune system in prostate cancer patients. Ten prostate cancer patients were supplemented daily with 150 mg of isoflavone for 2 months. Blood samples were collected baseline and 2 month after for analysis of PSA, serum lipid profiles, total antioxidant status (TAS), grade of DNA damage in lymphocytes, IL-6, VEGF and TNF -α. After 2 month isoflavone supplementation, increased significantly a total of estimated urinary isoflavone excretion and did not change PSA. Serum lipid profiles showed significant change in serum total cholesterol level (p=0.007). However, there was no significant change in HDL- and LDL-cholesterol levels. TAS was increased but not significant after isoflavone supplementation. Tail moment (TM) was decreased and especially tail length (TL) was decreased significantly (p=0.043). IL-6 level was decreased but VEGF level and TNF -α level were increased. The results of the present study led to the conclusion that the isoflavone dosage (150 mg) in supplement had positive effects on the serum total cholesterol level and DNA damage.