Enzyme activities in tissue of human benign prostatic hyperplasia after three months' treatment with the Sabal serrulata extract IDS 89 (Strogen®) or placebo

H. Weisser, B. Behnke, B. Helpap, D. Bach, M. Krieg

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Objective: The mechanism of action of plant extracts used for the medical treatment of human benign prostatic hyperplasia (BPH) is still unknown. In this prospective, randomized, double-blind trial, we investigated the possible influence of the Sabal serrulata extract IDS 89 (Strogen®) on epithelial and stromal enzyme activities of BPH tissue. Methods: 18 patients with BPH were randomly assigned to receive 3 x 2 capsules Strogen® uno (320 mg/capsule) (n = 8) or placebo (n = 10) daily for 3 months. The activity (V(max) and K(m)) of 5α-reductase, 3α-HSOR(red), 3β-HSOR(red), and creatine kinase was determined in mechanically separated epithelium and stroma of human BPH. Results: The multivariate correlation analysis revealed a positive correlation between therapy and the following enzyme alterations: (1) In epithelium, the substrate affinity of the 5α-reductase decreased slightly (increase of K(m) value). (2) In stroma, the V(max) value of the 3α-HSOR(red) increased statistically distinctly, leading to a moderate increase of V(max)/K(m). (3) In stroma, the V(max) value of the 3β-HSOR(red) increased moderately, but not statistically significant. (4) In stroma, the V(max) value of creatine kinase increased significantly, leading to a statistically distinct increase of V(max)/K(m). Conclusion: This double-blind, placebo-controlled clinical trial with the S. serrulata extract IDS 89 revealed significant biochemical changes at the cellular level of BPH tissue. However, the alterations are merely moderate, their biochemical causes and consequences regarding the pathophysiology of BPH rather uncertain. Therefore, more studies are needed before plant extracts like IDS 89 become valid candidates likewise synthetic substances already used for medical treatment of human BPH.

Original languageEnglish
Pages (from-to)97-101
Number of pages5
JournalEuropean Urology
Issue number1
Publication statusPublished - Jan 1 1997



  • Benign prostatic hyperplasia
  • Enzyme activity
  • Phytotherapy
  • Sabal serrulata

ASJC Scopus subject areas

  • Urology

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