Effects of the Sabal serrulata extract IDS 89 and its subfractions on 5α-reductase activity in human benign prostatic hyperplasia

Abstract

Extracts from fruits of Sabal serrulata are used in the treatment of human benign prostatic hyperplasia (BPH). Therefore, it is of interest whether this phytopharmacon has any influence on the androgen metabolism in the human prostate. It was found that the extract IDS 89 of Sabal serrulata inhibited dose dependently 5α‐reductase activity in the epithelium and stroma of human BPH, the mean inhibition being 29% and 45%, respectively. This inhibitory effect is mainly due to the saponifiable subfraction of IDS 89 showing a mean 5α‐reductase inhibition of 39% and 38% in epithelium and stroma, respectively. The inhibition was dose dependent and noncompetitive. At a testosterone concentration of 580 nM as substrate for 5α‐reductase, the main fatty acids of the extract IDS 89 gave rise to a percentual enzyme inhibition in the epithelium and stroma as follows: 51% and 42% (lauric acid), 5% and 0% (oleic acid), 43% and 34% (myristic acid), 2% and 0% (palmitic acid), respectively. The inhibitory effect of lauric acid was noncompetitive and dose dependent up to a concentration of 0.2 mM, the maximal inhibition in the epithelium and stroma being 52% and 45%, respectively. The nonsaponifiable subfraction, consisting mainly of phytosterols, showed a mean inhibition of 5α‐reductase in the epithelium and stroma of 15% and 10%, respectively. Finally, the hydrophilic subfraction, containing carbohydrates, amino acids, and polysaccharides, showed no inhibitory effect. The present in vitro studies suggest that the Sabal serrulata extract IDS 89 has an inhibitory effect on 5α‐reductase in the epithelium and stroma of human BPH. This inhibition is mainly due to the fatty acids of the saponifiable subfraction. © 1996 Wiley‐Liss, Inc.

A prospective study of the efficacy of Serenoa repens, Tamsulosin, and Serenoa repens plus Tamsulosin treatment for patients with benign prostate hyperplasia

“…The most described and studied phytotherapeutic agent for the medical treatment of symptomatic BPH is the lipidosterolic extract of SR, Permixon Ò , which is known as Prostagood Ò in Turkey. In vitro studies have shown that SR is a noncompetitive inhibitor of type I 5-alpha-reductase and non-competitively inhibits the type II isozyme [23,24]. Another most widely accepted mechanism of action by which SR has been suggested to improve voiding symptoms in men with BPH is through inhibition of dihydrotestosterone binding to the cytosolic androgen receptor in prostatic cells [25][26][27].…”

Isolation and Pharmacological Characterization of Fatty Acids from Saw Palmetto Extract

“…10%) and other chemical series (<2%) such as phytosterol, aliphatic alcohols and polypyrenic compounds. 4,[20][21][22] In H NMR spectroscopic analysis. The active fraction in column chromatography was further fractionated by RP-HPLC, and the receptor binding activity of each fraction was assessed, while focusing on a-adrenergic, muscarinic and 1,4-DHP receptors (Fig.…”

Die benigne Prostatahyperplasie - das Ergebnis einer altersbedingten Entgleisung der Androgen-Estrogen-Balance?

“…Letztendlich muß jedoch derzeit offen bleiben, welche pathobiochemische Rolle den in der menschlichen Prostata beschriebenen Akkumulationsphä-nomenen in der BPH-Entwicklung zukommt, da die zellulä ren Mechanismen, die diesen Phä nomenen zugrunde liegen, derzeit noch unbekannt sind. Jü ngere Untersuchungen unserer Arbeitsgruppe, die eine Abhä ngigkeit der 5a-Reduktaseaktivitä t vom zellulä ren Lipidenvironment zeigen, legen die Vermutung nahe, daß die zuvor beschriebenen Phä nomene zumindest z. T. durch altersabhä ngige posttranslationale Modifikationen bedingt sein kö nnten [27,28] …”