Epilobium Angustifolium L.

Epilobium Angustifolium L. A monocentric, randomized, double-blind, placebo-controlled clinical trial of Epilobium angustifolium L. extract with high oenothein B content on benign prostatic hyperplasia (BPH)

Introduction

Benign prostate hyperplasia (BPH) is a common condition in adult men. Particularly in Europe, interest is growing in E. angustifolium (fireweed) extracts (EAE), which are widely used due to their positive effects on BPH symptoms, despite limited human clinical trials. The purpose of this monocentric, randomized, double-blind, placebo-controlled clinical study in subjects with BPH was therefore to evaluate whether daily intake for 6 months of hard, gastric-resistant capsules containing chemically characterized EAE (500 mg) could provide significant symptom improvement. This study involved 128 adult men randomly assigned to receive either an EAE dietary supplement (N = 70) or placebo (N = 58) at four visits (baseline = t0, 15 days later = t1, 2 months later = t2, and 6 months later = t3) to evaluate post-void residual (PVR) and prostate volume (PV), prostate ultrasound, prostate-specific antigen (PSA), and neutrophil/lymphocyte ratio (N/L), nocturia, and the International Prostate Symptom Score (IPSS) as recorded by physicians prior to clinic visits in an outpatient setting. The EAE dietary supplement caused a significant decrease in PVR, as suggested by the reduction in IPSS, and consequently improved nocturia quality of life. No subjects reported adverse effects associated with oral intake of the EAE dietary supplement. Additionally, the EAE dietary supplement showed no hepatic or renal toxicity. As a result, EAE dietary supplements can be used to improve quality of life and overall kidney function in patients with BPH.

Definition

The American Urological Association defines benign prostatic hyperplasia (BPH) as a histological diagnosis referring to proliferation of smooth muscle and epithelial cells within the prostate transition zone, typically beginning at approximately age 25 and occurring in the second growth phase of the prostate. Gontero and colleagues estimated that BPH is present in 70% of adult men and that the epidemiology of this condition is not well characterized. A recent meta-analysis of 30 studies published by Nature in 2017 estimated that global BPH prevalence (occurrence rate) in individuals varies at rates between 14.0% and 40%, at 26.6%, and in individuals aged 80 and over at 36.8%. As the prostate enlarges, the gland exerts pressure on and constricts the urethra. The bladder wall thickens and may lose the ability to empty completely, leaving some urine in the bladder. Urethral narrowing can lead to acute and chronic urinary retention, which are the most important complications associated with BPH. While the former is a serious complication requiring hospitalization, the latter can cause other complications such as recurrent urinary tract infections, bladder stone formation, hematuria, and damage to the bladder wall and kidneys. The most common symptoms of BPH are incomplete bladder emptying, nocturia (that is, the need to urinate two or more times per night), urinary incontinence, the need to strain during urination, weak urine flow, sudden urge to urinate, slowed or delayed urination, painful urination, and blood in the urine. Furthermore, there is a significant relationship between benign prostatic hyperplasia/bladder outlet obstruction (BPH/BOO) and male erectile dysfunction. Literature data obtained from clinical studies show that the occurrence rate of these complications is low, but unfortunately this is sufficient for them to occur regularly in real life.  

Studies

Antioxidant activity: In preclinical studies of fireweed on prostate cells (LNCap), it improves cellular antioxidant defense by increasing SOD-1 protein and mRNA levels. SOD-1 is one of the most important endogenous antioxidant defense mechanisms. Inflammatory activity: In preclinical studies of fireweed on prostate cells (LNCap), it reduces inflammatory response by decreasing TNFα protein levels. TNFα is one of the most important pro-inflammatory cytokines.

Clinical Studies

A monocentric, randomized, double-blind, placebo-controlled clinical study with fireweed (15% Oenothein) was conducted on 128 humans with benign prostatic hyperplasia.   The International Prostate Symptom Score (IPSS) is a validated questionnaire for assessing BPH symptoms in men with urinary complaints. The score ranges from 0 to 35. These represent asymptomatic to highly symptomatic subjects. Results are generally represented by arrows to indicate participants' overall QoL (Quality of Life). The IPSS score decreased significantly, by approximately 2 points, between t0 and t3 in the group treated with fireweed and increased slightly (0.6 points) in the placebo group. This demonstrates an improvement in quality of life in subjects treated with Epilobium angustifolium L. and underscores the protective effect of this supplement. Subjects with BPH may experience difficulty emptying the bladder due to urethral narrowing. This can lead to acute/chronic urinary retention, the most important complication associated with BPH. Post-void residual volume (PVR), a measure of bladder emptying efficiency, was monitored by prostate ultrasound. Nocturia (the need to urinate two or more times per night) is a serious issue that significantly affects sleep quality, leading to sleep disturbances, reduced quality of life, and depression. In the fireweed group, the number of subjects with high urine volume with low residual in the bladder increased significantly, while the frequency of subjects with residual urine volume greater than 100 ml decreased. The frequency of subjects with no nocturia in the fireweed group increased by 21.7%, while in the placebo group it decreased by 10.2%. Additionally, the number of subjects urinating three or more times per night was completely eliminated in the treated group but remained unchanged in the placebo group.

Results

The metabolic profile of fireweed reveals the presence of a phytocomplex rich in various types of polyphenols. The presence of oenothein A and B in E. angustifolium extracts, which are converted to urolithins through intestinal fermentation thanks to other compounds in their content and which are known to have anti-inflammatory activity, suggests that the EAE dietary supplement may exert a beneficial effect against BPH through an anti-inflammatory mechanism. The results demonstrate that E. angustifolium dietary supplements can be used to improve quality of life in patients with BPH by reducing post-void residual volume and consequently nocturia and overall kidney function, without hepatic or renal toxicity.   Source Cristina Esposito, Cristina Santarcangelo, Raffaello Masselli, Giuseppe Buonomo, Giovanna Nicotra, Violetta Insolia, Maria D'Avino, Giuseppe Caruso, Antonio Riccardo Buonomo, Roberto Sacchi, Eduardo Sommella, Pietro Campiglia, Gian Carlo Tenore, Maria Daglia / Epilobium angustifolium L. extract with high content in oenothein B on benign prostatic hyperplasia: A monocentric, randomized, double-blind, placebo-controlled clinical trial, Biomedicine & Pharmacotherapy, Volume 138, 2021, 111414 / ISSN 0753-3322, https://doi.org/10.1016/j.biopha.2021.111414. (https://www.sciencedirect.com/science/article/pii/S0753332221001992)   Translator and Editor Haydar Poyraz - Sales Manager Arerko Kimya