NIS - libdoc.who.int - World Health Organization

WHO monographs on medicinal plants commonly used in the Newly Independent States (NIS)
concentration in plasma. The plasma membrane of the human prostate
contains specific SHBG receptors, and SHBG appears to play a role in the
development of BPH. A 10% hydroalcoholic extract of the root reduced
the binding capacity of SHBG (isolated from human plasma) for
5α-dihydrotestosterone by 67% in vitro (41). An aqueous extract of the
root (0.6–10.0 mg/ml) inhibited the binding of 125 I-labelled SHBG to human
prostate membranes in vitro (42). The lignan, secoisolariciresinol,
and a mixture of the isomeric compounds 13-hydroxy-9-cis,11-trans-octadecadienoic
acid and 9-hydroxy-10-trans,12-cis-octadecadienoic acid
isolated from a methanol root extract, reduced the binding of SHBG to
5α-dihydrotestosterone (18). Secoisolariciresinol and its main intestinal
transformation products, (–)-3,4-divanillyltetrahydrofuran and enterofuran,
displaced the binding of 5α-dihydrotestosterone to SHBG in vitro
by 60%, 95% and 73%, respectively (43).
Enzymatic activity
Intragastric administration of a 30% ethanol extract of the root to male
mice inhibited the activities of 5α-reductase and aromatase (ED 50
14.7 and
3.58 mg/ml, respectively) (44). However, a hydroalcoholic extract of the
root dissolved in dimethyl sulfoxide did not inhibit the activity of
5α-reductase from human prostate cells in vitro (up to 500 µg/ml) (45). A
standardized hydroalcoholic extract of the roots (IC 50
338 µg/ml) inhibited
aromatase activity in vitro. A heptane-soluble fraction of the extract
was the most effective inhibitor (IC 50
9 µg/ml) (36). Both ursolic acid and
14-octacosanol isolated from a methanol extract of the roots inhibited the
activity of aromatase in vitro (46). 9-Hydroxy-10-trans,12-cis-octadecadienoic
acid isolated from the roots inhibited the activity of aromatase in
vitro (19). Butanol, ether, ethyl acetate and hexane extracts of the roots
inhibited the activity of sodium- and potassium-adenosine triphosphatase
isolated from prostatic hyperplastic cells by 27.6–81.5% (47). In addition,
steroidal components of the roots, stigmast-4-en-3-one, stigmasterol and
campesterol (1 µmol/l to 1 mmol/l), inhibited sodium- and potassiumadenosine
triphosphatase activity by 23–67% (47).
Effect on prostate growth
Intragastric administration of a hexane extract of the roots (1.28 g daily)
to castrated rats did not inhibit prostate growth stimulated by testosterone
or dihydrotestosterone (45). Intraperitoneal administration of a hydroalcoholic
extract of the roots (20 mg/kg body weight) suppressed
testosterone-stimulated increases in prostate weight and prostatic ornithine
decarboxylase activity in castrated rats (48). Daily oral administra-
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