Pygeum

Other common names: African plum
Latin name: Prunus africana (Hook. f.) Kalkman [Rosaceae]
Latin synonyms: Pygeum africanum Hook. f.
Plant part: Bark




Pygeum bark has been traditionally used in central and southern
Africa to assist bladder and urinary function. In this traditional use,
the bark is ground into powder and mixed with milk. Modern formulation
of this botanical is a lipophilic extract of the bark. At least three
types of active compounds may be responsible for the therapeutic action
of the extract: pentacyclic terpenes, phytosterols, and ferulic acid
esters (Schulz, Hänsel, and Tyler, 2001).

Tadenan® is manufactured in France by Laboratoires Fournier.
The capsules contain 50 mg of a lipophilic extract of pygeum bark.
Tadenan is not sold in the United States.
Pigenil contains a pygeum bark extract (PrunuSelect™) manufactured
by Indena S.p.A., Italy. This extract has a plant to extract ratio
of 180:1, and is standardized to contain 11.7 to 14.3 percent sterols as
beta-sitosterol. Pigenil, in 50 mg capsules, was originally manufactured
by Inverni della Beffa in Italy. This product is not available in
the United States.


Prostatonin® contains extracts of both pygeum bark and nettle
(Urtica dioica L. spp. dioica) roots. This product is manufactured by
Pharmaton S.A. in Switzerland, and is sold in the United States by
Pharmaton Natural Health Products. It is available in softgel capsules
containing 25 mg pygeum extract, PY102 (200:1), and 300 mg nettle
extract, UR102 (5:1).


Pygeum preparations have been assessed in clinical studies for the
treatment of symptomatic benign prostatic hyperplasia (BPH), also
known as benign prostatic hypertrophy and prostatic adenoma. BPH
is a nonmalignant enlargement of the prostate common in men over
40 years of age. The symptoms of BPH include increased urinary urgency
and frequency, urinary hesitancy, intermittency, sensation of
incomplete voiding, and decreased force of the stream of urine. BPH
is linked with a normal change in hormone levels that occurs with aging.
Testosterone levels decrease while estrogen levels remain constant.
This change is implicated in BPH, since estrogens induce hyperplasia
(cell growth) in laboratory experiments. Further, BPH is
associated with an increase in the activity of 5-alpha-reductase, the
enzyme that converts testosterone to dihydrotesterone (DHT). The
levels of DHT are not increased, but the number of androgen receptors
seems to be. DHT has a greater affinity for androgen receptors
than testosterone, and is thought to modulate prostatic growth. However,
the pathology of BPH is not completely understood, and although
BPH is associated with prostate enlargement, the size of the
gland is not necessarily indicative of the degree of obstruction of the
urethra and the extent of symptoms (Barrett, 1999).


Predominant pharmaceutical treatments for BPH include alphareceptor
blockers and 5-alpha-reductase inhibitors. Alpha-receptor
blockers (e.g., prozosin, terazosin) are thought to relax smooth muscle
in the bladder neck and within the prostate, and thus reduce symptoms.
Five-alpha reductase inhibitors (e.g., finasteride) prevent the
transformation of testosterone into DHT. The rationale for this treatment
is that prostate enlargement may be linked to activation of androgen
receptors by DHT and a reduction in testosterone levels
(Barrett, 1999).


The clinical mode of action of pygeum has not been established,
but biochemical studies indicate that it has anti-inflammatory activity
and may inhibit 5-alpha-reductase. Nettle root extract, which is combined
with pygeum extract in the product Prostatonin®, may have
similar activity. Preparations of grass pollen and saw palmetto have
also been assessed clinically for treatment of BPH, and more information
about these botanicals is given in their sections in this book.
The mechanism of action of these botanicals is also not established,
but grass pollen has demonstrated anti-inflammatory activity, and
may reduce the growth of epithelial cells and fibroblasts. Suggested
pharmacological actions for saw palmetto include antiandrogenic,
anti-inflammatory, antiproliferative, and smooth muscle relaxation
(Marandola, et al., 1997; Awang, 1997; Barrett, 1999).