Extracts from Fruits of Saw Palmetto (Sabal serrulata) and Roots of Stinging Nettle (Urtica dioica): Viable Alternatives in the Medical Treatment of Benign Prostatic Hyperplasia and Associated Lower Urinary Tracts Symptoms

Abstract

Benign prostatic hyperplasia (BPH) and associated lower urinary tract symptoms (LUTS) are very common disorders in aging men. Despite the great clinical importance, many aspects of their aetiology remain uncertain although it is generally accepted that advanced age and testicular androgens are important requirements for the development of these complaints. The currently available therapeutic options include watchful waiting, changes of life style, medical treatments and invasive therapies. In many European countries the use of phytopharmaceuticals for the management of BPH and related LUTS is common and these products represent up to 80 % of all drugs prescribed for this disorder. In particularly, extracts from the fruits of saw palmetto (Sabal serrulata, syn. Serenoa repens) and the roots of stinging nettle (Urtica dioica) are popular. During the last years numerous papers have been published which elaborated on the pharmacological activities and the clinical assessment of these herbal remedies. These investigations have not only broadened the scientific basis for the rational use of phytotherapeutics but have also provided evidence for their therapeutic efficacy and favourable safety profile.

Abbreviations

AR:androgen receptor

bFGF:basic fibroblast growth factor

BPH:benign prostatic hyperplasia

CK:creatine kinase

DHT:dihydrotestosterone

EGF:epidermal growth factor

ER:estrogen receptor

HLE:human leukocyte elastase

HPLC:high pressure liquid chromatography

HSOR:hydroxysteroid oxidoreductase

IGF:insulin-like growth factor

IPSS:international prostate symptome scale

LTB₄:leukotriene B₄

LUTS:lower urinary tract symptoms

p.o.:per os

PDGF:platelet-derived growth factor

PgR:progesterone receptor

PLA₂:phospholipase A₂

PRL:prolactin

SHBG:sex hormone-binding globulin

SNRE:stinging nettle root extract

SPFE:saw palmetto fruit extract

TGF:transforming growth factor

TXB₂:thromboxan B₂

UDA:Urtica dioica agglutinin

UGS:urogenital sinus

Key words

Benign prostatic hyperplasia - lower urinary tract symptoms - phytopharmaceuticals - pharmacology - clinic - Sabal serrulata - Serenoa repens - Urtica dioica - saw palmetto - stinging nettle

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