5-Alpha-Reductase Inhibitors and Combination Therapy

Insights from computational studies about structural determinants of steroidal inhibitors in 5-alpha-reductase type II

5-alpha-reductase type II (5αR2) is an important protein involved in the reduction of testosterone to dihydrotestosterone, a product that promotes prostate growth and can lead to conditions such as prostate cancer and benign prostatic hyperplasia. This study presents a computational analysis of steroidal compounds with close structural relationships but notable differences in their biological activity. A set of molecules with reported half-maximal inhibitory concentrations, obtained under consistent conditions, was selected, and molecular docking and molecular dynamics simulations were performed. Considering the covalent inhibition mechanism of this protein, key atomic distances, root mean square deviations, and binding free energy were investigated to explain the significant differences in biological activity. The data suggest that the key to inhibitory capacity lies in the conformation that optimally facilitates bond formation between the NADPH cofactor and the α,β-unsaturated system of the inhibitors within the 5αR2 pocket. Considering that the protein pocket is rich in hydrophobic residues, introducing an atom such as fluorine, which increases the hydrophobicity of the ligand, may alter the favorable conformation within the pocket. This, in turn, could compromise the ability of the ligand to form a covalent bond with NADPH. Given the covalent nature of the inhibition mechanism, stability within the catalytic site plays a secondary role. Understanding these structural features is crucial for designing new potential 5αR2 inhibitors, particularly steroidal compounds, that aim to leverage a covalent mechanism of inhibition.

Post-finasteride syndrome - a true clinical entity?

This review critically examines Post-Finasteride Syndrome (PFS), a condition eventually reported by men who have used finasteride for androgenetic alopecia or benign prostatic enlargement and experienced persistent adverse effects after discontinuation. We explore the clinical manifestations, including sexual dysfunction, neuropsychiatric symptoms, and physical changes, that collectively challenge both diagnosis and management. This review evaluates the evidence for PFS, discusses potential mechanisms including neurobiological alterations, genetic predispositions, and addresses the controversies surrounding its existence and recognition by the medical community. Emphasis is placed on the role of patient education and the need for thorough risk assessment before prescribing finasteride. Although contrasting data from literature, men treated with finasteride could develop a plethora of non-neglectable physical and psychological symptoms identifying PFS. A multidisciplinary approach to research, policy-making, and patient advocacy is essential to better understand, diagnose, and manage PFS, underlining the necessity for greater awareness and scientific inquiry into this contentious and impactful syndrome.

The latest in clinical trial results of 5-alpha reductase inhibitors in combination regimens for benign prostatic hyperplasia

INTRODUCTION

BPH/male LUTS is a prevalent condition in the aging male population with multifactorial pathophysiology. Pharmacotherapy remains the cornerstone of treatment in patients who fail conservative treatment. 5-α-Reductase inhibitors (5-ARIs) are the only class of medication shown to reduce the risk of acute retention and BPH-related surgery and, thus, are commonly used along with other "short acting" medications in combination treatments.

AREAS COVERED

Combination treatments with α-blockers and 5-ARIs have been investigated extensively in high quality trials that prove the long-term efficacy of such treatments with acceptable rates of side effects. Combination treatments involving 5-ARIs and other classes of medications (anticholinergics, b3 agonists, PDEI) have been shown to be beneficial in the short term and but studies with longer follow-up periods are required to fully establish their role.

EXPERT OPINION

A-blocker/5-ARI combination treatment is a reasonable approach for patients with male LUTS/BPH who are at increased risk of disease progression or have incomplete response to monotherapies. Other combination treatments with 5-ARIs and PDEI or anticholinergics/β-3 agonists can be tried based on predominant symptoms or side effect profile, but patients should be informed about the lack of long-term data.

Network meta-analysis of the treatment safety and efficacy of different energy systems in prostate vaporization

Many clinical trials and meta-analyses have examined vaporization with different energy instruments has been recognized by the American Urological Association (AUA) and the European Association of Urology (EAU) as a promising treatment for benign prostate hyperplasia. However, there is still a lack of evidence for a network comparison between different vaporization devices. The PubMed, Embase, Cochrane and Web of Science databases were searched to identify randomized controlled trials (RCTs) of different energy systems for prostate vaporization. Pairwise and network meta-analyses (NMA) were performed to analyze the outcome regarding surgery time, complications, short-term maximum urine flow rate (Qmax), and long-term Qmax. The Stata software was used for paired meta-analysis. A Bayesian NMA model with ADDIS software was applied to achieve the indirect comparison of different energy systems. Node-splitting analysis and inconsistency factors were used to test inconsistency for closed-loop indirect comparison. Fifteen studies were included in this study, involving three types of energy systems used in prostate vaporization: diode laser (wavelength: 980 nm, power: 200-300 W, mode: continuous), green-light laser (wavelength: 532 nm, power: 80-180 W, mode: continuous), and bipolar plasma vaporization (bipolar electrode, power: 270-280 W, mode: pulsed). In the conventional paired meta-analysis, significantly better short-term efficacy was found in green light laser vaporization, while no significant difference was detected in other parameters. According to the results of the NMA, a greenlight laser is recommended for prostate vaporization rather than the other two systems. When considering operation time, overall complications, short-term Qmax, and long-term Qmax, there were no significant differences among green-light laser vaporization, diode laser vaporization, and bipolar vaporization in BPH treatment. However, according to the probability ranking and benefit-risk analysis results, the green-light laser might be the best energy system for prostate vaporization in BPH treatment.

Lifestyle habits to prevent the development of benign prostatic hyperplasia: Analysis of Japanese nationwide datasets

Objectives

Benign prostatic hyperplasia (BPH) refers to nonmalignant hyperplasia of prostate tissue, which causes lower urinary tract symptoms and has become a global public health concern in the aging population. The purpose of this study is to identify modifiable factors, which would prevent or delay BPH development.

Methods

The association between BPH marker drugs and climate-, socioeconomic-, health condition-, and lifestyle habits-related variables was investigated by analyzing nationwide datasets which were collected in 2018, aggregated by prefecture (administrative unit), and published by Japanese ministries. Uroselective α₁ receptor blockers and dutasteride were used as marker drugs referring to BPH prevalence. Correlation analysis, multiple linear regression analysis, and binomial logistic regression analysis were conducted with 47 Japanese prefectures as the unit.

Results

The variables which showed |r| > 0.5 by correlation analysis were exercise habits (r = -0.5696), smoking habits (r = 0.6116), and daily drinking (r = 0.6001) for uroselective α₁ receptor blockers, and antihypertensive medication (r = 0.5971), smoking habits (r = 0.6598), a small amount of drinking (r = -0.5292), and serum alanine aminotransferase (r = 0.6814) for dutasteride. Multiple linear regression equations were constructed by including these variables (R ²  = 0.5453 for uroselective α₁ receptor blockers and R ²  = 0.5673 for dutasteride). Binomial logistic regression analysis found a significant association between climate in the resident area and BPH development.

Conclusion

This ecological study, analyzing Japanese nationwide datasets, demonstrates that healthy lifestyle habits, especially avoidance of smoking, implementation of exercise in daily life, and a small amount of alcohol consumption, are important to prevent or delay BPH development. High blood pressure and high serum alanine aminotransferase are suggested as risk factors of BPH development.

Steroidogenesis in castration-resistant prostate cancer

Castration resistance is in part attributable to aberrant activation of androgen receptor (AR) signaling by the intracrine activation of androgen precursors derived from adrenal glands. To overcome this, novel AR pathway inhibitors (ARPIs) that suppress androgen synthesis by CYP17 inhibition or AR activation by antiandrogen effects have been developed. However, primary or acquired resistance to these ARPIs occurs; in turn attributable, at least in part, to the maintained androgen milieu despite intensive suppression of AR signaling similar to castration resistance. In addition to the classical pathway to produce potent androgens such as testosterone and dihydrotestosterone, the alternative pathway and the backdoor pathway which bypasses testosterone to produce dihydrotestosterone have been shown to play a role in intratumor steroidogenesis. Furthermore, the 11β-hydroxyandrostenedione pathway to produce the potent oxygenated androgens 11-ketotestosterone and 11-ketodihydrotestosterone has been suggested to be functional in prostate cancer. These steroidogenesis pathways produce potent androgens that promote tumor resistance to endocrine therapy including novel ARPIs. Here, we overview the current evidence on the pathological androgen milieu by altered metabolism and transport in prostate cancer, leading to resistance to endocrine therapy.

New Endoscopic In-office Surgical Therapies for Benign Prostatic Hyperplasia: A Systematic Review

CONTEXT

In recent years, new technologies have been developed to treat benign prostatic enlargement (BPE). Three of these devices may be utilized in office and are promising additions.

OBJECTIVE

To systematically review all clinical trials investigating prostatic urethral lift (PUL), water vapor thermal therapy (WVTT), and temporary implantable nitinol device (TIND), with emphasis on clinical efficacy and complications.

EVIDENCE ACQUISITION

We performed a systematic review of PubMed/Medline database in November 2020 according to Preferred Reporting Items for Systematic Review and Meta-analysis guidelines.

EVIDENCE SYNTHESIS

Of 168 articles identified, 18 met the inclusion criteria. Evidence consisted of few randomized controlled trials, and multiple single-arm prospective and retrospective studies. Among the three modalities, PUL demonstrates rare occurrence of serious complications but higher retreatment rates at short- and long-term follow-up. WVTT offers lower retreatment rates with a similar safety profile. TIND studies report varying rates of retreatment and complications. All technologies offer low rates of erectile and ejaculatory dysfunction, although the risk appears to be highest for WVTT (<10.8%).

CONCLUSIONS

Among the emerging technologies introduced to treat BPE, the in-office PUL, WVTT, and TIND systems are valuable additions to the current surgical options. These systems offer unique advantages that should be considered in the shared decision-making process.

PATIENT SUMMARY

In this report, we identified all clinical trials reporting on the efficacy and safety of the in-office prostatic urethral lift (PUL), water vapor thermal therapy (WVTT), and temporary implantable nitinol device (TIND) systems for the treatment of benign prostatic enlargement. We found that PUL and WVTT demonstrate acceptable outcomes in terms of functional improvement, retreatment, and complications. More data with longer follow-up are required to further evaluate TIND, but early results are promising.

Ethanol-extracted Cameroonian propolis: Antiproliferative effects and potential mechanism of action in prostate cancer

The present study was conducted to evaluate in vitro and in vivo antiproliferative potential of the Cameroonian propolis and to elucidate its underlying mechanism. In vitro, ethanol-extracted propolis (EEP) was tested on cell growth, cell proliferation, cell cycle, cell death mechanism and cell migration. The cell cycle- and apoptosis-regulating proteins were assessed by Western blotting. In vivo the testosterone-induced benign prostatic hyperplasia (BPH) in Wistar rat was used to evaluate the antiproliferative potential of EEP. EEP reduced DU145 and PC3 cell survival with an IC₅₀ of 70 and 22 μg/ml respectively. It increased the number of late apoptotic cells, the amount of cells in G0/G1 phase in DU145 and PC3 cells at 50 µg/ml. Cell cycle proteins (cdk1, pcdk1 and their related cyclins A and B) were down-regulated in both DU145 and PC3 cells, while cdk2 and pcdk2 were down-regulated only in PC3 cells. The pro-apoptotic Bax protein was up-regulated, while the anti-apoptotic Akt and pAKT, and Bcl-2 proteins were down-regulated. It increased prostate cell adhesion and chemotaxis. EEP reduced prostate weight, volume and epithelial thickness in rats. We demonstrated for the first time that Cameroonian propolis is endowed with in vitro and in vivo antiproliferative properties in the prostate.

Sex hormones modulate pathogenic processes in experimental traumatic brain injury

Clinical and animal studies have revealed sex-specific differences in histopathological and neurological outcome after traumatic brain injury (TBI). The impact of perioperative administration of sex steroid inhibitors on TBI is still elusive. Here, we subjected male and female C57Bl/6N mice to the controlled cortical impact (CCI) model of TBI and applied pharmacological inhibitors of steroid hormone synthesis, that is, letrozole (LET, inhibiting estradiol synthesis by aromatase) and finasteride (FIN, inhibiting dihydrotestosterone synthesis by 5α-reductase), respectively, starting 72 h prior CCI, and continuing for a further 48 h after CCI. Initial gene expression analyses showed that androgen (Ar) and estrogen receptors (Esr1) were sex-specifically altered 72 h after CCI. When examining brain lesion size, we found larger lesions in male than in female mice, but did not observe effects of FIN or LET treatment. However, LET treatment exacerbated neurological deficits 24 and 72 h after CCI. On the molecular level, FIN administration reduced calpain-dependent spectrin breakdown products, a proxy of excitotoxicity and disturbed Ca²⁺ homeostasis, specifically in males, whereas LET increased the reactive astrocyte marker glial fibrillary acid protein specifically in females. Examination of neurotrophins (brain-derived neurotrophic factor, neuronal growth factor, NT-3) and their receptors (p75^NTR , TrkA, TrkB, TrkC) revealed CCI-induced down-regulation of TrkB and TrkC protein expression, which was reduced by LET in both sexes. Interestingly, FIN decreased neuronal growth factor mRNA expression and protein levels of its receptor TrkA only in males. Taken together, our data suggest a sex-specific impact on pathogenic processes in the injured brain after TBI. Sex hormones may thus modulate pathogenic processes in experimental TBI.

LXRs, SHP, and FXR in Prostate Cancer: Enemies or Ménage à Quatre With AR?

Androgens and androgen receptor (AR, NR3C4) clearly play a crucial role in prostate cancer progression. Besides, the link between metabolic disorders and the risk of developing a prostate cancer has been emerging these last years. Interestingly, “lipid” nuclear receptors such as LXRα/NR1H3 and LXRβ/NR1H2 (as well as FXRα/NR1H4 and SHP/NR0B2) have been described to decrease the lipid metabolism, while AR increases it. Moreover, these former orphan nuclear receptors can regulate androgen levels and modulate AR activity. Thus, it is not surprising to find such receptors involved in the physiology of prostate. This review is focused on the roles of liver X receptors (LXRs), farnesoid X receptor (FXR), and small heterodimeric partner (SHP) in prostate physiology and their capabilities to interfere with the androgen-regulated pathways by modulating the levels of active androgen within the prostate. By the use of prostate cancer cell lines, mice deficient for these nuclear receptors and human tissue libraries, several authors have pointed out the putative possibility to pharmacologically target these receptors. These data open a new field of research for the development of new drugs that could overcome the castration resistance in prostate cancer, a usual phenomenon in patients.

Drugs for benign prostatic hypertrophy

Benign prostatic hyperplasia is a common condition It can cause problems with urine storage and voiding and the severity of symptoms may be unrelated to the size of the prostate

When drug treatment is required benign prostatic hyperplasia can be managed with monotherapy or combination therapy Most patients are managed with selective alpha blockers

Patients with larger prostate volumes may benefit from a 5-alpha-reductase inhibitor usually in combination with an alpha blocker

New Insights in Prostate Cancer Development and Tumor Therapy: Modulation of Nuclear Receptors and the Specific Role of Liver X Receptors

Prostate cancer (PCa) incidence has been dramatically increasing these last years in westernized countries. Though localized PCa is usually treated by radical prostatectomy, androgen deprivation therapy is preferred in locally advanced disease in combination with chemotherapy. Unfortunately, PCa goes into a castration-resistant state in the vast majority of the cases, leading to questions about the molecular mechanisms involving the steroids and their respective nuclear receptors in this relapse. Interestingly, liver X receptors (LXRα/NR1H3 and LXRβ/NR1H2) have emerged as new actors in prostate physiology, beyond their historical roles of cholesterol sensors. More importantly LXRs have been proposed to be good pharmacological targets in PCa. This rational has been based on numerous experiments performed in PCa cell lines and genetic animal models pointing out that using selective liver X receptor modulators (SLiMs) could actually be a good complementary therapy in patients with a castration resistant PCa. Hence, this review is focused on the interaction among the androgen receptors (AR/NR3C4), estrogen receptors (ERα/NR3A1 and ERβ/NR3A2), and LXRs in prostate homeostasis and their putative pharmacological modulations in parallel to the patients' support.

Effects of 5-alpha reductase inhibitors: new insights on benefits and harms

PURPOSE OF REVIEW

The use of 5-alpha reductase inhibitors (5ARIs) for the treatment of benign prostatic hyperplasia (BPH) and other diseases has been proposed and studied. However, the controversy about its benefits and harms for other diseases has persisted. In this review, we will discuss the newly identified effects of 5ARIs based on recently published studies.

RECENT FINDINGS

These drugs are currently recommended in clinical guidelines for BPH. However, the reporting of adverse effects, including sexual dysfunction as well as neurologic, endocrine, and cardiovascular effects, have been controversial. There are reports of additional effects of 5ARI in prostate cancer and bladder cancer. Although 5ARIs have been prescribed for the treatment of androgenic alopecia (AGA), postfinasteride syndrome can result, with symptoms that range from sexual dysfunction to muscle atrophy.

SUMMARY

Clinical applications of 5ARIs have been established for the treatment of BPH and AGA from a series of randomized controlled trials. The adverse effects of 5ARIs affect only a small proportion of treated patients and can be resolved with discontinued treatment. It will be necessary to establish the mechanism by which 5ARIs elicit these effects through better designed studies.

The impact of polypharmacy and drug interactions among the elderly population in Western Sicily, Italy

AIM

Primary endpoint was to report polypharmacy distribution in the general population vs ≥65 years old people and to examine the frequency of drug-drug interactions (DDIs) in the Health Local Unit of Palermo, Italy, in relationship with patients' age.

METHODS

Drug prescription data for the year 2014 were extracted from the database of the Local Health Unit of Palermo Province, Italy. Patients were divided into five age groups (0-13, 14-64, 65-69, 70-74, and ≥75 year old). The detection of potential DDIs in polypharmacy profiles was performed with NavFarma software (Infologic srl, Padova, Italia), with DDI classification provided by tool Micromedex Drug Reax (Truven Health Analitics, Michigan, USA).

RESULTS

We analyzed data of 1,324,641 patients, and 15,801,191 medical prescription were recorded; of these, 11,337,796 regarded chronic conditions. The drug prescriptions reached the highest values in the 65-69 and 70-74 age groups (p = 0.005 and p = 0.008 vs age 14-64 respectively). An overall amount of 6,094,373 DDIs were detected, of which 47,173 were contraindicated. Median number of DDIs was higher in 65-69 and 70-74 age groups (p = 0.008 and p = 0.012 vs age 14-64, respectively). Regarding contraindicated DDIs a significant difference was detected comparing 14-64 vs ≥65 age groups (p = 0.010 vs 65-69 group, p = 0.005 vs 70-74 group and ≥75 group).

CONCLUSIONS

Polypharmacy is a phenomenon acquiring increasing dimensions also in our province. It interests particularly the older subjects, and assumes a dramatic accent when it is put in relationship with the frequency of DDIs. A proactive vigilance about potential life threatening drug interactions is mandatory.

The Simultaneous measurement of serum testosterone and 5α-dihydrotestosterone by gas chromatography-mass spectrometry (GC-MS)

BACKGROUND

Simultaneous measurement of testosterone (T) and 5α-dihydrotestosterone (DHT) is important for diagnosing androgen deficiency states and hyperandrogenism in males and females, respectively. However, immunoassays used for T and DHT determination suffer from inadequate specificity and sensitivity, while tandem mass spectrometry is expensive and demanding in use.

METHODS AND RESULTS

We developed a selective gas chromatography-mass spectrometry (GC-MS) method for parallel T and DHT measurement. The assay showed a linear response up to 46.5nmol/L, intra- and interassay imprecision and inaccuracy <15% and recoveries in spiked samples >90% for both analytes. The limit of quantitation was 0.117nmol/L for T and 0.168nmol/L for DHT. Comparison with immunoassays revealed good agreement for T in males, but a bias in favour of immunoassays at low concentrations for T in females and DHT in both sexes. We established reference ranges for T and DHT and suggest interval partitioning for T according to age in men and menstrual cycle in women. Assay validation in a clinical setting suggests that measuring DHT or T/DHT ratio may help identify patients with polycystic ovary syndrome.

CONCLUSION

We developed a selective, simple and inexpensive GC-MS method for parallel measurement of T and DHT with potential use in the clinical laboratory.

Fibrillar collagen genes are not coordinately upregulated with TGF β1 expression in finasteride-treated prostate

Benign prostatic hyperplasia (BPH) is the most common cause of lower urinary tract symptoms (LUTS) in older men. In this regard, recent studies have attempted to define the relationships between prostatic fibrosis, LUTS, and increased expression of transforming growth factor β1 (TGF β1) in BHP. Therapeutic approaches for BPH such as 5-α-reductase inhibitors and alpha-adrenergic blocking agents increase TGF β1 expression in the prostatic tissue. Here, we investigated the effects of the 5-α-reductase inhibitor-finasteride-on rat ventral prostate tissue, especially with regard to the tissue distribution and gene expression of fibrillar collagens. Adult Wistar rats (n = 15) were treated with finasteride (25 mg/kg/day) by subcutaneous injection for 7 and 30 days. Age-matched, vehicle-treated (n = 15) adult Wistar rats were used as control. Finasteride treatment reduced prostate size and increased the area of types I and III collagen fibers in the prostatic stroma. As expected, TGF β1 mRNA expression was upregulated by finasteride treatment. However, COL1A1 and COL3A1 mRNA expressions decreased after both 7 and 30 days of finasteride treatment, suggesting that finasteride treatment promotes prostate parenchyma and stroma changes, which lead to the observed types I and III collagen remodeling without de novo collagen synthesis. The upregulation of TGF β1 mRNA and protein associated with the 5-α-reductase inhibitor is more closely related to epithelial and stromal cell death pathways than to prostatic fibrosis.