Marks L S, Hess D L, Dorey F J, Luz Macairan M, Cruz Santos P B, Tyler V E
Urological Sciences Research Foundation, Culver City, California, USA.
Urology. 2001 May;57(5):999-1005. doi: 10.1016/s0090-4295(00)01052-9.
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.
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.
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.
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.
确定锯棕榈草药混合物（SPHB）与非那雄胺相比对前列腺组织雄激素水平的影响，并评估针吸活检作为此类测定的组织来源。
在三组有症状的良性前列腺增生男性中，对5至10毫克活检标本（18号针芯）测量睾酮和双氢睾酮（DHT）的前列腺水平：15名接受慢性非那雄胺治疗的男性与7名未治疗的对照者；4名接受前列腺腺瘤切除术以确定取样变异性的男性（各10个标本）；以及40名参与SPHB与安慰剂为期6个月随机试验的男性，在治疗前后进行检测。
发现前列腺组织DHT水平比睾酮水平高几倍（5.01对1.51纳克/克），慢性非那雄胺治疗后该比例发生逆转（1.05对3.63纳克/克）。非那雄胺对两种雄激素的作用具有统计学意义（P<0.01），在接受非那雄胺治疗的患者和对照患者之间，个体值几乎没有重叠。在随机试验中，SPHB组的组织DHT水平从6.49纳克/克降至4.40纳克/克，降低了32%（P<0.005），安慰剂组无显著变化。
对于对照者与接受非那雄胺治疗的男性，通过针吸活检标本获得的组织雄激素值，无论是绝对值还是变化百分比，都与先前使用手术切除的前列腺组织体积所报告的值相似。因此，通过针吸活检测定前列腺雄激素是可行的，并为个体患者进行系列研究提供了可能性。在一项随机试验中，SPHB对前列腺DHT水平的抑制作用虽适度但显著，这为5-α还原酶抑制是该物质作用机制这一假说提供了一定支持。
