Comparison of the Effects of Hexanic Extract of Serenoa repens (Permixon) and Tamsulosin on Inflammatory Biomarkers in the Treatment of Benign Prostatic Hyperplasia-Related Lower Urinary Tract Symptoms

Lipid Profile and 5α-Reductase Inhibition Activity of Proprietary Ultrahigh-Pressure Supercritical Carbon Dioxide and Hexane Saw Palmetto Extracts

Inhibition of 5α-reductase (5αR), which blocks the conversion of testosterone to its active metabolite, dihydrotestosterone, has been shown to impact further prostate enlargement (benign prostatic hyperplasia, or BPH). Clinical trials of standardized lipidosterolic extracts of Serenoa repens (LSESr), also known as standardized extracts of saw palmetto, have demonstrated improvement in lower urinary tract symptoms (LUTS) and delayed progression of BPH. The aim of this preclinical study was to compare two standardized LSESr, a proprietary ultrahigh-pressure supercritical carbon dioxide extract of S. repens (UHP-sCESr) and the well-established hexanic extract of S. repens (HESr), for both 5αR inhibition activity and lipid profiles. UHP-sCESr and HESr had nearly identical inhibition curves and comparable IC50 values for 5αR-1 (9.25 ± 0.87 and 9.86 ± 0.11 μg/mL, respectively; p = 0.43) and 5αR-2 (7.47 ± 0.07 and 7.72 ± 0.05 μg/mL, respectively; p = 0.0544). UHP-sCESr and HESr also had comparable lipid profiles based on similar total fatty acid levels (87.7% and 91.5%, respectively), weight/weight comparisons of individual fatty acids, and individual fatty acid ratios to lauric acid. In addition, UHP-sCESr meets the standard set by the United States Pharmacopeia (USP) monograph for authenticity and purity for a supercritical carbon dioxide (SCCO2) extract of saw palmetto, whereas HESr meets the standard set by the European Medicines Agency (EMA) for a well-established medicinal product. In conclusion, based on enzyme inhibition curves and IC50 values, a standardized lipid profile is important to achieve comparable mechanisms of action for lipidosterolic extracts of saw palmetto. UHP-sCESr offers a comparable, standardized LSESr for men with LUTS/BPH in regions where the proprietary HESr is not available.

Inflammation is a target of medical treatment for lower urinary tract symptoms associated with benign prostatic hyperplasia

Purpose

To review the role of a persistent prostatic inflammatory status (PIS) in the development and progression of benign prostatic hyperplasia (BPH) associated with lower urinary tract symptoms (LUTS) and which medical therapies approved for LUTS/BPH may reduce persistent PIS.

Methods

Literature search in PubMed up to July 2019.

Results

The cause of histologically defined persistent PIS or chronic prostatic inflammation is multifactorial. It is evident in many men with LUTS/BPH, particularly in older men and in men with a large prostate volume or more severe (storage) LUTS. Additionally, persistent PIS is associated with an increased risk of acute urinary retention and symptom worsening. Of medical therapies approved for LUTS/BPH, the current evidence for a reduction of persistent PIS is greatest for the hexanic extract of Serenoa repens (HESr). This treatment relieves LUTS to the same extent as α₁-adrenoceptor antagonists and short-term 5α-reductase inhibitors. Limited evidence is available on the effect of other mainstream LUTS/BPH treatments on persistent PIS.

Conclusions

Persistent PIS plays a central role in both the development and progression of LUTS/BPH. In men with LUTS/BPH who have a high chance of harbouring persistent PIS, HESr will not only improve LUTS, but also reduce (underlying) inflammation. Well-designed clinical studies, with a good level of evidence, are required to better evaluate the impact of BPH/LUTS medical therapies on persistent PIS.

Electronic supplementary material

The online version of this article (10.1007/s00345-020-03106-1) contains supplementary material, which is available to authorized users.