Issue: 60 Page: 18
Effects of Saw Palmetto Extract on Prostate Tissue of Men with BPH
by Heather S. Oliff, PhD
HerbalGram. 2003; 60:18 American Botanical Council
Effects of Saw Palmetto Extract on Prostate Tissue of Men with BPH
Reviewed: Veltri R, Marks L, Miller C, et al. Saw palmetto
alters nuclear measurements reflecting DNA content in men with symptomatic BPH:
Evidence for a possible molecular mechanism. Urology 2002;60(4):617-22.
Saw palmetto (Serenoa repens (W. Bartram) Small, Arecaceae)
fruit extract is one of the most widely used treatments for symptomatic benign
prostatic hyperplasia (BPH). In many men, BPH results in bothersome urinary symptoms.
Based on the results of two previously published papers,1,2 a specific
saw palmetto herbal blend (SPHB*) is associated with prostatic epithelial contraction
(cells getting smaller) and decreases in tissue levels of dihydrotestosterone
(DHT). (This is the third publication on the SPHB based on the same clinical trial
that resulted in the two previous publications.)
Although the general mechanism of action is known, the molecular
mechanisms for these findings are not known. The authors hypothesize that the
molecular basis for the action might be due to alterations in DNA content and
chromatin (genetic material in a cell) structure and organization of prostate
epithelial cells. One way to measure genetic alterations in tissue is to determine
the quantitative nuclear grade (QNG). QNG is a biomarker that describes the nuclear
size, shape, and chromatin structure and organization. Changes in QNG may reflect
alterations in gene expression in response to treatment or changes in disease
state. This randomized, double-blind, placebo-controlled clinical trial examines
the effects of SPHB on the epithelial nuclear chromatin structure of men with
symptomatic BPH.
Forty-four men (mean age 65 years) with chronic symptoms of
bladder outlet obstruction, prostate enlargement, and a positive prostate symptom
score participated in the trial. Patients received either an inert placebo or
SPHB. Both softgel capsules looked identical. Patients took one capsule 3 times
daily with meals for 6 months. A prostate biopsy was performed at baseline and
after 6 months of treatment. QNG was calculated by measuring 60 nuclear morphometric
descriptors (NMDs). Examples of NMDs are perimeter, area, and cell class.
At baseline, there was no difference in the 60 NMDs between
the placebo and SPHB treatment groups. After 6 months of placebo treatment, the
NMDs did not significantly change. In contrast, after SPHB treatment, 25 of the
60 NMDs significantly changed. Therefore, according to the study, 6 months of
SPHB treatment alters the DNA chromatin structure and organization in prostate
epithelial cells.
The authors conclude that the clear-cut chromatin alterations
suggest a molecular basis for the proprietary saw palmetto blend’s clinical
effects. However, because of the multi-component nature of this herbal blend,
it is not certain whether the benefits can be attributed solely to the saw palmetto
extract or to the combined action of all the ingredients in the blend.
–Heather S. Oliff, PhD
* SPHB: 106 mg of standardized saw palmetto liposterolic
extract combined with 80 mg nettle root extract (Urtica dioica L. ssp.
dioica, Urticaceae), 160 mg pumpkin seed extract (Cucurbita pepo L., Cucurbitaceae),
33 mg lemon flavonoids, and 190 mg vitamin A (Nutrilite, Buena Park, CA).
References:
1. Marks LS, Partin AW, Epstein JI, et al. Effects of a
saw palmetto herbal blend in men with symptomatic benign prostatic hyperplasia.
J Urol 2000;163:1451—6.
2. Marks LS, Hess DL, Dorey FJ, et al. Tissue effects of
saw palmetto and finasteride: use of biopsy cores for in situ quantification of
prostatic androgens. Urology 2001;57:999—1005
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