The Effect of Isoflavone Intake on Serum Biochemical Profiles and Antioxidant System in Patients with Prostatic Diseases / 대한비뇨기과학회지

ABSTRACT

PURPOSE: There is growing evidence that soy isoflavones exert estrogenic activity and inhibitory effects of steroid metabolizing enzymes. The present preclinical study was undertaken to evaluate the short term effects of isoflavone supplementation on serum prostate specific antigen (PSA), lipid profile and the antioxidant system in elderly men with prostate diseases. MATERIALS AND METHODS: Sixteen benign prostatic hyperplasia (BPH) patients, excluding those taking drugs that might influence the serum biochemical profiles and 10 metastatic prostate cancer (PC) patients were recruited. The patients were supplemented with soy isoflavones (150mg/day) for 2 months, after which blood was collected for analysis of the serum biochemical profiles. In the PC groups, the total antioxidant status (TAS) and comet assay were performed for evaluation of the antioxidant system. RESULTS: Compared to the baseline, the total cholesterol was significantly decreased in both the BPH and PC groups (p=0.034 and 0.032, respectively). The WBC was significantly increased in the BPH group (p=0.009), but the Hb, platelets, RBC, ALP, BUN/creatinine, GOT and GPT were unchanged in both groups. The PSA was decreased in both groups, but without statistical significance. However, the TAS levels in the 5 PC patients with a low baseline were increased. The Comet assay resulted revealed no change in the tail moment, but the tail length was significantly decreased (p=0.043) in the PC group. CONCLUSIONS: This preclinical study suggests that short-term isoflavone supplementation has no harmful effects on the biochemical profiles. Although it may not regulate the PSA level completely, it showed improvements in the lipid profile and antioxidant system that might affect the biological progression of prostate disease. To assess whether soy isoflavone may be used in controlling human prostate disease, a long-term placebo controlled additional trial is warranted.