RELEVANT RESEARCH STUDIES AND ARTICLES
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- Safarinejad MR. Urtica dioica for treatment of benign prostatic hyperplasia: a prospective, randomized, double-blind, placebo-controlled, crossover study. J Herb Pharmacother.. 2005;5(4):1-11
*Quick Summary of Study: Urtica dioica, commonly known as Stinging Nettle, was shown to have a positive effect against symptoms associated with benign prostatic hyperplasia.
To determine the effects of therapy with Urtica dioica for symptomatic relief of lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH).
MATERIAL AND METHODS:
A 6-month, double-blind, placebo-controlled, randomized, partial crossover, comparative trial of Urtica dioica with placebo in 620 patients was conducted. Patients were evaluated using the International Prostate Symptom Score (IPSS), the maximum urinary flow rate (Qmax), postvoid residual urine volume (PVR), Serum Prostatic- Specific Antigen (PSA), testosterone levels, and prostate size. At the end of 6-month trial, unblinding revealed that patients who initially received the placebo were switched to Urtica dioica. Both groups continued the medication up to 18 months.
558 patients (90%) completed the study (287/305, 91% in the Urtica dioica group, and 271/315, 86% in the placebo group). By intention- to-treat analysis, at the end of 6-month trial, 232 (81%) of 287 patients in the Urtica dioica group reported improved LUTS compared with 43 (16%) of 271 patients in the placebo group (P < 0.001). Both IPSS and Qmax showed greater improvement with drug than with placebo. The IPSS went from 19.8 down to 11.8 with Urtica dioica and from 19.2 to 17.7 with placebo (P = 0.002). Peak flow rates improved by 3.4 mL/s for placebo recipients and by 8.2 mL/s for treated patients (P < 0.05). In Urtica dioica group, PVR decreased from an initial value of 73 to 36 mL (P < 0.05). No appreciable change was seen in the placebo group. Serum PSA and testosterone levels were unchanged in both groups. A modest decrease in prostate size as measured by transrectal ultrasonography (TRUS) was seen in Urtica dioica group (from 40.1 cc initially to 36.3 cc; P < 0.001). There was no change in the prostate volume at the end of study with placebo. At 18-month follow-up, only patients who continued therapy, had a favorable treatment variables value. No side effects were identified in either group.
In the present study, Urtica dioica have beneficial effects in the treatment of symptomatic BPH. Further clinical trials should be conducted to confirm these results before concluding that Urtica dioica is effective.
2. Pais P. Potency of a novel saw palmetto ethanol extract, SPET-085, for inhibition of 5alpha-reductase II. Adv Ther. 2010 Aug; 27(8):555-63.
*Quick Summary of Study: Saw palmetto may reduce the symptoms of benign prostatic hyperplasia by inhibitating the enzyme that converts testosterone into DHT.
The nicotinamide adenine dinucleotide phosphate (NADPH)-dependent membrane protein 5alpha-reductase irreversibly catalyses the conversion of testosterone to the most potent androgen, 5alpha-dihydrotestosterone (DHT). In humans, two 5alpha-reductase isoenyzmes are expressed: type I and type II. Type II is found primarily in prostate tissue. Saw palmetto extract (SPE) has been widely used for the treatment of lower urinary tract symptoms secondary to benign prostatic hyperplasia (BPH). The mechanisms of the pharmacological effects of SPE include the inhibition of 5alpha-reductase, among other actions. Clinical studies of SPE have been equivocal, with some showing significant results and others not. These inconsistent results may be due, in part, to varying bioactivities of the SPE used in the studies.
The aim of the present study was to determine the in vitro potency of a novel saw palmetto ethanol extract (SPET-085), an inhibitor of the 5alpha-reductase isoenzyme type II, in a cell-free test system. On the basis of the enzymatic conversion of the substrate androstenedione to the 5alpha-reduced product 5alpha-androstanedione, the inhibitory potency was measured and compared to those of finasteride, an approved 5alpha-reductase inhibitor.
SPET-085 concentration-dependently inhibited 5alpha-reductase type II in vitro (IC(50)=2.88+/-0.45 microg/mL). The approved 5alpha-reductase inhibitor, finasteride, tested as positive control, led to 61% inhibition of 5alpha-reductase type II.
SPET-085 effectively inhibits the enzyme that has been linked to BPH, and the amount of extract required for activity is very low compared to data reported for other extracts. It can be concluded from data in the literature that SPET-085 is as effective as a hexane extract of saw palmetto that exhibited the highest levels of bioactivity, and is more effective than other SPEs tested. This study confirmed that SPET-085 has prostate health-promoting bioactivity that also corresponds favorably to that reported for the established prescription drug standard of therapy, finasteride.
3. Sinescu I, Geavlete P, Multescu R, Gangu C, Miclea F, Coman I, Ioiart I, Ambert V, Constantin T, Petrut B,Feciche B. Long-term efficacy of Serenoa repens treatment in patients with mild and moderate symptomatic benign prostatic hyperplasia. Urol Int. 2011; 86(3):284-9.
*Quick Summary of Study: Saw palmetto shows long term efficacy in the reduction of symptoms associated with benign prostatic hyperplasia.
The study aimed to evaluate the long-term efficacy of treatment with extract of Serenoa repens (Prostamol Uno) in patients with lower urinary tract symptoms (LUTS) induced by benign prostatic hyperplasia (BPH).
PATIENTS AND METHODS:
We studied 120 patients with mild or moderate LUTS induced by BPH, maximal urinary flow (Q(max)) <15 ml with a voided volume â‰¥150 ml, prostate-specific antigen <4 ng/ml, and residual urinary volume <150 ml, treated daily for 24 months with one capsule of 320 mg ethanolic extract of Serenoa repens.
Statistically significant improvements in the International Prostate Symptom Score (5.5 points), quality of life (QoL; 1.8 points), Q(max) (5.6 ml/s), International Index of Erectile Function (IIEF; 6.4 points) and reduction in residual urinary volume were observed during the study period. The mean prostate volume at 24 months was 36 ml, compared to 39.8 ml at baseline.
Long-term treatment with 320 mg ethanolic extract of Serenoa repens proved to be efficient in reducing urinary obstruction, improving symptomatology and QoL of BPH patients. It also had a positive effect on sexual function, demonstrated by the statistically significant increase in the IIEF
4. Bonvissuto G, Minutoli L, Morgia G, Bitto A, Polito F, Irrera N, Marini H, Squadrito F, Altavilla D. Effect of Serenoa repens, lycopene, and selenium on proinflammatory phenotype activation: an in vitro and in vivo comparison study. Urology.2011 Jan; 77(1):248.e9-16
*Quick Summary of Study: Animal study shows that Lycopene, Sal palmetto and Selenium inhibited the inflammation cascade caused when animals were induced with LPS, a pro- inflammatory compound.
To investigate the antiinflammatory activity of Serenoa repens (SeR), LY, and) on proinflammatory phenotype in rat peritoneal macrophages (Ms) stimulated with Salmonella enteritidis lipopolysaccharide (LPS) and in the prostate of rats with partial bladder outlet obstruction. SeR, combined with other compounds, such as LY and Se is used to relieve symptoms associated with benign prostatic hyperplasia (BPH). Inflammation plays a pivotal role in the pathogenesis of BPH and represents a target for anti-BPH drugs.
After stimulation with 1 Î¼g/mL of LPS, peritoneal rat MÎ¦s were coincubated with LY (2 Î¼g/mL), Se (0.03 Î¼g/mL), and SeR (10 Î¼g/mL), alone or in association (LY-Se-SeR) and with RPMI. Inducible cyclooxygenase (COX-2), 5-lypoxygenase (5-LOX), inducible nitric oxide synthase (iNOS), and inhibitor ÎºBÎ± (IÎºB-Î±) protein were evaluated by Western blot. Nuclear factor-kappa B (NF-ÎºB) binding activity was measured by electrophoretic mobility shift assay. Tumor necrosis factor-Î± (TNF-Î±) gene expression was investigated by real-time polymerase chain reaction. We also evaluated malondialdehyde (MDA) and nitrite levels.
LPS stimulation produced a proinflammatory phenotype in rat peritoneal MÎ¦s. LY, Se, and SeR inhibited the inflammatory cascade, but the Ly-Se-SeR association caused a greater inhibitory effect on the expression of COX-2, 5-LOX, and iNOS. The Ly-Se-SeR association showed a higher efficacy in reducing the loss of IÎºB-Î±, the increased NF-ÎºB binding activity, the enhanced mRNA levels of TNF-Î±, the elevated MDA, and nitrite content. The LY-Se-SeR association in vivo caused a greater inhibitory effect on prostate inflammation induced in rats by partial bladder outlet obstruction.
The LY-Se-SeR association might be useful in the treatment of BPH