Objectives. To determine the effects of a saw palmetto herbal blend (SPHB) compared with finasteride on prostatic tissue androgen levels and to evaluate needle biopsies as a source of tissue for such determinations.
Methods. Prostate levels of testosterone and dihydrotestosterone (DHT) were measured on 5 to 10-mg biopsy specimens (18-gauge needle cores) in three groups of men with symptomatic benign prostatic hyperplasia: 15 men receiving chronic finasteride therapy versus 7 untreated controls; 4 men undergoing prostate adenomectomy to determine sampling variability (10 specimens each); and 40 men participating in a 6-month randomized trial of SPHB versus placebo, before and after treatment.
Results. Prostatic tissue DHT levels were found to be several times higher than the levels of testosterone (5.01 versus 1.51 ng/g), that ratio becoming reversed (1.05 versus 3.63 ng/g) with chronic finasteride therapy. The finasteride effect was statistically significant for both androgens (P <0.01), and little overlap of individual values between finasteride-treated and control patients was seen. In the randomized trial, tissue DHT levels were reduced by 32% from 6.49 to 4.40 ng/g in the SPHB group (P <0.005), with no significant change in the placebo group.
Conclusions. For control versus finasteride-treated men, the tissue androgen values obtained with needle biopsy specimens were similar—both for absolute values and the percentage of change—to those previously reported using surgically excised volumes of prostatic tissue. The quantification of prostatic androgens by assay of needle biopsies is thus feasible and offers the possibility of serial studies in individual patients. The SPHB-induced suppression of prostatic DHT levels, modest but significant in a randomized trial, lends an element of support to the hypothesis that inhibition of the enzyme 5-alpha reductase is a mechanism of action of this substance.
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- Phytotherapy in treatment of benign prostatic hyperplasia.Urology. 1996; 48: 12-20
- Saw palmetto for the treatment of men with lower urinary tract symptoms.J Urol. 2000; 163: 1408-1412
- Saw palmetto extracts for treatment of benign prostatic hyperplasia.JAMA. 1998; 280: 1604-1609
- Effects of a saw palmetto herbal blend in men with symptomatic benign prostatic hyperplasia.J Urol. 2000; 163: 1451-1456
- Prostate tissue composition and response to finasteride in men with symptomatic benign prostatic hyperplasia.J Urol. 1997; 157: 2171-2178
- Prostatic growth.Br J Urol. 1995; 76: 5-10
- Effects of long term treatment with Serenoa repens (Permixon) on the concentrations and regional distribution of androgens and epidermal growth factor in benign prostatic hyperplasia.Prostate. 1998; 37: 77-83
- Effects of the sabal serrulata extract IDS 89 and its subfractions on 5α-reductase activity in human benign prostatic hyperplasia.Prostate. 1996; 28: 300-306
- Inhibition of androgen metabolism and binding by a liposterolic extract of “Serenoa Repens B” in human foreskin fibroblasts.J Steroid Biochem. 1984; 20: 515-519
- Comparison of finasteride (Proscar), a 5α-reductase inhibitor, and various commercial plant extracts in in vitro and in vivo 5α-reductase inhibitors.Prostate. 1993; 22: 43-51
- Comparison of finasteride (Proscar) and Serenoa repens (Permixon) in the inhibition of 5-α reductase in healthy male volunteers.Eur Urol. 1994; 26: 247-252
- Estrogens in fetal and maternal plasma of the rhesus monkey.Endocrinology. 1975; 97: 425-430
- A quantitative analysis of the physiological role of estradiol and progesterone in the control of tonic and surge secretion of luteinizing hormone in the rat.Endocrinology. 1978; 102: 142-150
- Sex steroids in the umbilical circulation of fetal rhesus monkeys from the time of gonadal differentiation.J Clin Endocrinol Metab. 1980; 50: 900-905
- Prostatic effects induced in dogs by chronic or acute oral administration of 5α-reductase inhibitors.Prostate. 1986; 9: 65-75
- Finasteride, an inhibitor of 5α-reductase, suppresses prostatic dihydrotestosterone in men with benign prostatic hyperplasia.J Clin Endocrinol Metab. 1992; 74: 505-507
- Dihydrotestosterone measured in core biopsies from prostatic tissues.Am J Clin Oncol. 1988; 11: 27-29
- The effect of finasteride in men with benign prostatic hyperplasia.N Engl J Med. 1992; 327: 1185-1191
- Effect of finasteride on serum PSA concentration in men with benign prostatic hyperplasia.Urol Clin North Am. 1993; 20: 627-636
- Evidence of atrophy and apoptosis in the prostates of men given finasteride.J Clin Endocrinol Metab. 1996; 81: 814-819
- The effect of finasteride on the prostate gland in men with elevated serum prostate-specific antigen levels.Br J Cancer. 1998; 78: 413-418
- Comparison of phytotherapy (Permixon) with finasteride in the treatment of benign prostate hyperplasia.Prostate. 1996; 29: 231-240
Accepted: November 1, 2000
Received in revised form: November 1, 2000
Received: July 27, 2000
☆This study was supported in part by NIH grants RR00163 and HD18185 and by the Nutrilite Division of Amway Corporation.
© 2001 Elsevier Science Inc. Published by Elsevier Inc. All rights reserved.