Repeated finasteride administration promotes synaptic plasticity and produces antidepressant- and anxiolytic-like effects in female rats

Finasteride is used in female-pattern hair loss, hirsutism, and polycystic ovarian syndrome. It inhibits 5α-reductase, which is an important enzyme in the biosynthesis of neurosteroids. The effects of finasteride treatment on mental health in female patients as well as the effects of repeated/chronic finasteride administration in female rodents are still unknown. Accordingly, in our study, we administered finasteride (10, 30, or 100 mg/Kg, s.c.) for 6 days in female rats and evaluated behavior, plasma steroid levels, and synaptic plasticity. Depression-like behavior was evaluated using forced swim test (FST) and splash test. Anxiety-like behavior was evaluated using novelty-suppressed feeding task (NSFT), elevated plus maze (EPM), open field test (OFT), and light-dark test (LDT). Plasma steroid levels were assessed using ELISA and synaptic plasticity by field potential recordings. We observed that finasteride decreased total immobility duration in FST, indicating antidepressant-like effect and decreased the latency to first bite in NSFT, showing anxiolytic-like effect. We also found a significant increase in plasma estradiol and a significant decrease in plasma corticosterone level. Furthermore, field potential recordings showed that finasteride increased hippocampal long-term potentiation. These results indicate that repeated finasteride administration in female rats may have antidepressant- and anxiolytic-like effect, which might be mediated by enhanced estradiol levels or decreased corticosterone levels. Further studies are required to validate the molecular mechanisms underlying the effects of finasteride in female rats. Understanding the mechanisms will help us in developing novel neurosteroid-based therapeutics in the treatment of neuropsychiatric disorders in women.

Potential side effects of currently available pharmacotherapies in male lower urinary tract symptoms suggestive of benign prostatic hyperplasia

INTRODUCTION

The drug classes of α1-adrenoceptor antagonists, 5α-reductase inhibitors, and phosphodiesterase type 5 inhibitors are guideline-recommended treatments of lower urinary tract symptoms suggestive of benign prostatic hyperplasia; muscarinic receptor antagonists and β3-adrenoceptor agonists are also recommended if storage symptoms are insufficiently addressed with one of the other three drug classes.

AREAS COVERED

We provide a narrative review (no formalized literature searches performed) of the tolerability of these drug classes with emphasis on the more recently introduced medications, on combination treatment, and on more lately emerging risks.

EXPERT OPINION/COMMENTARY

The tolerability profiles are distinct between drug classes but, with few exceptions, similar within a drug class. Within a drug, formulations with longer duration of action tend to have better tolerability. Efficacy gains using combination treatment at least partly come at a cost of lesser tolerability. Greater susceptibility to experience adverse events based on age, comorbidities, and comedications appears conceptually important but remains under-investigated in this therapeutic area.

A Comprehensive Review of Natural Alternatives for Treatment of Alopecia with an Overview of Market Products

Alopecia or hair loss is a widespread issue that has significant effects on personal well-being for both genders nationally and internationally. In addition, alopecia causes extreme emotional stress and negatively impacts the psychological health and self-esteem of cancer patients suffering from chemotherapy-induced alopecia. Unfortunately, available synthetic medications are costly, invasive, or have extreme adverse effects. On the contrary, natural and herbal hair loss products are widely available in the local and international markets in variable pharmaceutical forms with different mechanisms of action, namely, androgen antagonists, nutritional supplements, vasodilators, and 5α-reductase inhibitors or dihydrotestosterone blockers. Thus, it is of great importance to encourage researchers to investigate these natural alternatives that can act as potent therapeutic agents having diverse mechanisms of action as well as limited side effects. Currently, natural remedies are considered a fast-rising pharmaceutical segment with demand from a wide range of consumers. In this study, we present a review of reported herbal remedies and herb combinations recommended for hair loss and their mode of action, along with an overview of available market products and formulations, their composition, and declared effects. In addition, a general outline of the different forms of alopecia, its causes, and recommended treatments are mentioned as well. This was all done with the aim of assisting further studies with developing standardized natural formulations for alopecia as many were found to lack standardization of their bioactive ingredients and efficiency confirmation.

Phytosterols in hull-less pumpkin seed oil, rich in ∆7-phytosterols, ameliorate benign prostatic hyperplasia by lowing 5α-reductase and regulating balance between cell proliferation and apoptosis in rats

Background

Pumpkin seed oil is widely used to treat benign prostatic hyperplasia (BPH), a common disease in elder men. However, its active components and mechanism have remained to be elucidated.

Objective

The objective of the present study was to investigate the active components of pumpkin seed oil and its mechanism against BPH.

Design

Total phytosterol (TPS) was isolated from hull-less pumpkin (Cucurbita pepo L. var. Styriaca) seed oil and analyzed by gas chromatography/mass spectrometry (GC/MS). Three phytosterols were purified by preparative HPLC (high performance liquid chromatography) and confirmed by NMR (nuclear magnetic resonance). TPS (3.3 mg/kg body weight, 1 mL/day/rat) was administered intragastrically to the testosterone propionate-induced BPH rats for 4 weeks. The structure changes of prostate tissues were assessed by hematoxylin & eosin (H&E) staining. The expression of androgen receptor (AR) and steroid receptor coactivator 1 (SRC-1) was analyzed by immunohistochemistry, while that of 5α-reductase (5AR), apoptosis, or proliferation-related growth factors/proteins was detected by real-time quantitative polymerase chain reaction or western blotting.

Results

The ∆⁷-phytosterols in TPS reached up to 87.64%. Among them, 24β-ethylcholesta-7,22,25-trienol, 24β-ethylcholesta-7,25(27)-dien-3-ol, and ∆⁷-avenasterol were confirmed by NMR. TPS treatment significantly ameliorated the pathological prostate enlargement and restored histopathological alterations of prostate in BPH rats. It effectively suppressed the expressions of 5AR, AR, and coactivator SRC-1. TPS inhibited the expression of proliferation-related growth factor epidermal growth factor, whereas it increased the expressions of apoptosis-related growth factor/gene transforming growth factor-β1. The proliferation-inhibiting effect was achieved by decreasing the ERK (extracellular signal-regulated kinase) phosphorylation, while apoptosis was induced by Caspase 3 activation through JNK (c-Jun N-terminal kinase) and p38 phosphorylation.

Conclusion

TPS from hull-less pumpkin seed oil, with ∆⁷-phytosterols as its main ingredients, is a potential nutraceutical for BPH prevention.

Optimization and Transfollicular Delivery of Finasteride-Loaded Proniosomes for Hair Growth Stimulation in C57BL/6Mlac Mice

The study aimed to develop the finasteride-loaded proniosome (FLP) to enhance the transfollicular delivery of finasteride (FN). The response surface methodology (RSM) combined with central composite design (CCD) with three independent variables (FN concentrations, total lipid content, and cholesterol content) was used to optimize the FLP preparation. The particles size, zeta potential, entrapment efficiency, and drug loading capacity of the FLP were analyzed. The transfollicular delivery of the optimum formulation was investigated in vitro. In vivo hair growth stimulation study was performed on C57BL/6Mlac mice dorsal areas. The Draize primary skin irritation test for erythema and edema was performed in the New Zealand white rabbit skin. The optimum FLP consists of 5.0 mM of FN, 10.1 mM of total lipid content, and 50.0% of the cholesterol in the total lipid. The prepared proniosome delivered the FN significantly (p < 0.05), compared to the naked finasteride solution in a dose- and time-dependent manner. The FLP treatment significantly increases the number and size of hair follicles in a dose-dependent manner. The efficiency of 1% FLP was comparable to the 2% minoxidil solution. The FLP exhibited no skin irritation after 72 h. Therefore, the results demonstrated that the FLP could stimulate hair growth via a transfollicular delivery system.

Geranylated Coumarins From Thai Medicinal Plant Mammea siamensis With Testosterone 5α-Reductase Inhibitory Activity

Geranylated coumarin constituents, kayeassamin I (1) and mammeasins E (2) and F (3) were newly isolated from the methanol extract of the flowers of Mammea siamensis (Calophyllaceae) originating in Thailand, along with five known isolates, such as mammea E/BC (23), deacetylmammea E/AA cyclo D (31), deacetylmammea E/BB cyclo D (32), mammea A/AA cyclo F (34), and mammea A/AC cyclo F (35). These compounds (1–3) were obtained as an inseparable mixture (ca. 1:1 ratio) of the 3″R and 3″S forms, respectively. Among the isolated coumarins from the extract, mammeasins E (2, 22.6 μM), A (4, 19.0 μM), and B (5, 24.0 μM), kayeassamins E (9, 33.8 μM), F (10, 15.9 μM), and G (11, 17.7 μM), surangin C (13, 5.9 μM), and mammeas A/AA (17, 19.5 μM), E/BB (22, 16.8 μM), and A/AA cyclo F (34, 23.6 μM), were found to inhibit testosterone 5α-reductase.

The role of 5α-reductase inhibitors in gastro-oesophageal cancer risk: A nested case-control study

PURPOSE

The strong male predominance of gastro-oesophageal cancer suggests that sex hormones play an important role. 5α-Reductase (5AR) inhibitors have antiandrogen effects and have been shown to decrease cancer cell proliferation and metastasis. We conducted the first epidemiologic investigation into the association between 5AR inhibitor use and gastro-oesophageal cancer risk.

METHODS

We conducted a nested case-control study within the Scottish Primary Care Clinical Information Unit Research database. Male cases diagnosed with oesophageal or gastric cancer between 1999 and 2011 were matched to up to five male controls based on birth year, diagnosis year, and general practice. We used electronic prescribing records to ascertain medication use. We used conditional logistic regression to calculate odds ratios (ORs) for the association between 5AR inhibitor use and cancer risk, after adjusting for comorbidities and aspirin, statin, or proton pump inhibitor use.

RESULTS

The study included 2003 gastro-oesophageal cancer cases and 9650 controls. There was some evidence of reduced gastro-oesophageal cancer risk among 5AR inhibitor users (adjusted OR = 0.75; 95% CI, 0.56-1.02), particularly for finasteride (adjusted OR = 0.68; 95% CI, 0.50-0.94). These decreases were more marked among those who received at least 3 years of 5AR inhibitors (adjusted OR = 0.54; 95% CI, 0.27-1.05; P value = .071) or finasteride (adjusted OR = 0.49; 95% CI, 0.24-0.99; P value = .046).

CONCLUSIONS

We found evidence of reduced gastro-oesophageal cancer risk among users of 5AR inhibitors, particularly finasteride. However, larger epidemiological studies are required before randomised controlled trials are considered.

Association between 5α-reductase inhibitors therapy and incidence, cancer-specific mortality, and progression of prostate cancer: evidence from a meta-analysis

5α-reductase inhibitors (5-ARI) are widely employed for the treatment of benign prostatic hyperplasia. It has been noted that 5-ARI exhibit the potential to attenuate the risk of prostate cancer, but consistent agreement has not been achieved. Moreover, the effect of 5-ARI on cancer-specific mortality and progression of prostate cancer remains unclear. Therefore, the goal of the current meta-analysis was to elucidate the impact of 5-ARI on the incidence and progression of prostate cancer. We searched for all studies assessing the effect of 5-ARI on risk of prostate cancer in PubMed, Embase, Medline, and Cochrane Library databases. Pooled relative risk (RR) and corresponding 95% confidence intervals (CIs) were accepted to evaluate the association between 5-ARI and the risk of prostate cancer. Synthetic results implied that subjects who accepted 5-ARI compared with the placebo group experienced a distinctly weakened overall incidence of prostate cancer (RR = 0.74; 95% CI: 0.66–0.82; P < 0.001). Subgroup analyses further revealed that 5-ARI reduction of the incidence of prostate cancer was limited to low-grade (Gleason score 2–6; RR = 0.68; 95% CI: 0.57–0.81; P < 0.001) and intermediate-grade tumors (Gleason score 7; RR = 0.81; 95% CI: 0.67–0.97; P = 0.023), but not high-grade tumors (Gleason score >7; RR = 1.19; 95% CI: 0.98–1.43; P = 0.069). The results also showed that 5-ARI treatment did not significantly alter prostate cancer-specific mortality (RR = 1.0; 95% CI: 0.95–1.05; P = 0.916). In addition, it was worth noting that 5-ARI treatment acted in a protective role that presented a dramatic benefit to delay the progression of low-risk tumors (RR = 0.58; 95% CI: 0.43–0.78; P < 0.001).

Chinese Skullcap (Scutellaria baicalensis Georgi) inhibits inflammation and proliferation on benign prostatic hyperplasia in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Chinese Skullcap (Scutellaria baicalensis Georgi), which is part of the 50 fundamental herbs of Traditional Chinese Medicine, has been extensively used in the several East Asian countries to treat pyrexia, micturition disorder and inflammation. Although skullcap has effective properties on various diseases, the effects and molecular mechanism of Chinese Skullcap on BPH are still needed for better understanding.

AIM OF THE STUDY

In present study, we aimed to demonstrate the efficacy of Chinese Skullcap root extract (SRE) in testosterone-induced BPH rats and investigate the exact regulatory mechanism involved.

MATERIALS AND METHODS

We followed a protocol of testosterone-induced BPH. Rats were allocated into five groups: Group 1, control; Group 2, BPH-induced rats; Group 3, BPH-induced rats administrated with finasteride; Group 4, BPH-induced rats administrated with SRE 100 mg/kg/day; Group 5 - BPH-induced rats administrated with SRE 200 mg/kg/day. We measured the weight of prostate, and thickness of prostate using H&E staining. Western blotting, immunostaining and real-time PCR were used to measure proliferation- and inflammation-relative markers. To confirm the effects of SRE on apoptotic events in BPH-induced tissues, we performed the TUNEL assay.

RESULTS

Compared with the untreated group, the SRE administration group suppressed pathological alterations, such as prostate growth and increase in serum DHT and 5α-reductase levels. Furthermore, SRE significantly obliterated the expression of AR and PCNA. SRE also restored Bax/Bcl-2 balance, inducing apoptosis in rats with BPH. These effect of SRE was more prevalent than commercial 5α-reductase inhibitor, finasteride.

CONCLUSIONS

Taken together, we propose that SRE suppresses abnormal androgen events in prostate tissue and inhibits the development of BPH by targeting inflammation- and apoptosis-related markers. These finding strengthens that SRE could be used as plant-based 5α-reductase inhibitory alternative.

Exploration of Novel 5α-Reductase Inhibitors for Benign Prostatic Hyperplasia by 2D/3D QSAR, Cytotoxicity Pre-ADME and Docking Studies

BACKGROUND

5α-Reductase (5AR), an NADPH dependent enzyme, is expressed in most of the prostate epithelial cells. By converting testosterone (T) into more potent androgen dihydrotestosterone (DHT), it plays an important role in men physiology and represents an efficient therapeutic target for androgen-dependent diseases. Over the last few years, significant efforts have been made in order to develop 5AR inhibitors (5ARI) to treat Benign Prostatic Hyperplasia because of excessive production of DHT.

METHODS

In the present study, 2D and 3D QSAR pharmacophore models have been generated for 5ARI based on known IC50 values with extensive validations. The four featured 2D pharmacophore based PLS model correlated the topological interactions (SsOHE-index); semi empirical (Quadrupole2) and physicochemical descriptors (Mol. Wt, Bromines Count, Chlorines Count) with 5AR inhibitory activity, and has the highest correlation coefficient (r2 = 0.98, q2 =0.84; F = 57.87, pred r2 = 0.88). Internal and external validation was carried out using test and proposed set of compounds. The contribution plot of electrostatic field effects and steric interactions generated by 3D-QSAR showed interesting results in terms of internal and external predictability. The well-validated 2D PLS, and 3D kNN models were used to search novel 5AR inhibitors with different chemical scaffold. The compounds were further sorted by applying ADMET properties and in vitro cytotoxicity studies against prostate cancer cell lines PC-3. Molecular docking studies have also been employed to investigate the binding interactions and to study the stability of docked conformation in detail.

RESULTS

Several important hydrophobic and hydrogen bond interactions with 5AR lead to the identification of active binding sites of 4AT0 protein in the docked complex, which include the gatekeeper residues ALA 63A (Chain A: ALA63), THR 60 A (Chain A: THR60), and ARG 456 A (Chain A: ARG456), at the hinge region.

CONCLUSION

Overall, this study suggests that the proposed compounds have the potential as effective inhibitors for 5AR.

A 52-week multicenter randomized controlled study of the efficacy and safety of add-on dutasteride and imidafenacin to tamsulosin in patients with benign prostatic hyperplasia with remaining overactive bladder symptoms (DIrecT study)

Objective

The aim of this study was to examine the long‐term efficacy of combination of tamsulosin 0.2 mg + dutasteride 0.5 mg + imidafenacin 0.2 mg (TDI) therapy compared with tamsulosin + dutasteride (TD) therapy for 52 weeks in benign prostatic hyperplasia (BPH) patients with a prostate volume (PV) ≥30 mL and remaining overactive bladder (OAB) symptoms after having received tamsulosin for ≥8 weeks. Previously, we reported that the improvement in OAB symptoms at 24 weeks was significantly greater in the TDI than TD group.

Methods

BPH patients with OAB symptoms after ≥8 weeks tamsulosin were randomly assigned to the TDI or TD group in a ratio of 1:1 ratio, and followed‐up for 52 weeks. Changes in the OAB Symptom Score (OABSS), International Prostate Symptom Score (IPSS), and post‐void residual (PVR) were evaluated.

Results

In all, 163 patients were randomized, and 125 patients (76.7%) completed 52 weeks of treatment. At Week 52, there were significant decreases in the OABSS and IPSS storage subscore compared with baseline in the TDI versus TD group, but the change in the total IPSS did not differ significantly between the two groups. There was no change in PVR from Week 24 to Week 52 in either group.

Conclusions

For BPH patients with PVR ≥30 mL and remaining storage symptoms despite tamsulosin monotherapy, TDI treatment showed better results in terms of improved OAB symptoms than TD treatment up to 52 weeks.

Finasteride nano-transferosomal gel formula for management of androgenetic alopecia: ex vivo investigational approach

Introduction

Finasteride (FIN) is known as type II 5α-reductase inhibitor, which has been approved for the treatment and prevention of androgenetic alopecia. Administration of FIN by oral route has led to undesirable systemic side effects that include mood disturbance, gynecomastia, decreased libido, erectile dysfunction, and ejaculation disorder. The aim was to improve FIN delivery through skin layers and hair follicles that could possibly reduce its major side effects resulting from long-term oral administration for the treatment and prevention of male pattern baldness.

Materials and methods

FIN was formulated as nano-transferosomal (NTF) gel formulations (F1–3). The prepared formulations were characterized for encapsulation efficiency, particle size, ex vivo skin permeation, and kinetic modeling. In addition, visualization of NTF skin penetration using a fluorescence laser microscope was carried out for the selected formula (F2).

Results and discussion

The results showed that FIN encapsulation efficiency percentage was 69.72 ± 8.36, 89.43 ± 6.82, and 93.1 ± 1.93 for F1, F2, and F3, respectively. FIN-NTF average vesicle sizes were 299.6 ± 45.6, 171 ± 25.6, and 197.4 ± 29.1 nm for F1, F2, and F3, respectively. FIN-NTF formulations (F1–3) showed enhancement and improvement in the amount of FIN permeated compared with raw FIN gel formula. The NTF formula revealed uniform fluorescence (rhodamine) intensity across rat skin, which indicated improved delivery through skin layers compared with control gel formula.

Conclusion

These results indicated that NTF gel formula showed the ability to boost FIN delivery across skin layers and could be applied as an alternative for oral therapy.

The 5α-Reductase Inhibitor Finasteride Exerts Neuroprotection Against Ischemic Brain Injury in Aged Male Rats

Progesterone (P4) exerts potent neuroprotection both in young and aged animal models of stroke. The neuroprotection is likely to be mediated by allopregnanolone (ALLO) metabolized from P4 by 5α-reductase, since the neuroprotection is attenuated by the 5α-reductase inhibitor finasteride, which was done only with young animals though. Thus, we do not know the contribution of ALLO to the P4-induced neuroprotection in aged animals. We examined effects of finasteride on the P4-induced neuroprotection in aged (16-18-month-old) male rats subjected to transient focal cerebral ischemia. Transient focal cerebral ischemia was induced by left middle cerebral artery occlusion (MCAO) and occlusion of the bilateral common carotid arteries. MCAO rats were given an 8 mg/kg P4 6 h after MCAO followed by the same treatment once a day for successive 3 days. Finasteride, a 5α-reductase inhibitor, at 20 mg/kg was intraperitoneally injected 30 min prior to the P4-injections. P4 markedly reduced neuronal damage 72 h after MCAO, and the P4-induced neuroprotection was apparently suppressed by finasteride in the aged animals. However, post-ischemic administration of finasteride alone (20 mg/kg) significantly prevented neuronal damage and the impairment of Rotarod performance after MCAO in aged male rats, but not in young ones. The androgen receptor antagonist flutamide markedly suppressed the neuroprotection of finasteride in the cerebral cortex, but not in the striatum, suggesting the androgen receptor-dependent mechanism of the finasteride-induced neuroprotection in the cerebral cortex. Our findings suggested, for the first time, the potential of finasteride as a therapeutic agent in post-ischemic treatment of strokes in aged population.

High-throughput and direct measurement of androgen levels using turbulent flow chromatography liquid chromatography-triple quadrupole mass spectrometry (TFC-LC-TQMS) to discover chemicals that modulate dihydrotestosterone production in human prostate cancer cells

OBJECTIVES

To develop a high-throughput screening system to measure the conversion of testosterone to dihydrotestosterone (DHT) in cultured human prostate cancer cells using turbulent flow chromatography liquid chromatography-triple quadrupole mass spectrometry (TFC-LC-TQMS).

RESULTS

After optimizing the cell reaction system, this method demonstrated a screening capability of 103 samples, including 78 single compounds and 25 extracts, in less than 12 h without manual sample preparation. Consequently, fucoxanthin, phenethyl caffeate, and Curcuma longa L. extract were validated as bioactive chemicals that inhibited DHT production in cultured DU145 cells. In addition, naringenin boosted DHT production in DU145 cells.

CONCLUSION

The method can facilitate the discovery of bioactive chemicals that modulate the DHT production, and four phytochemicals are potential candidates of nutraceuticals to adjust DHT levels in male hormonal dysfunction.

Change of Ultrasound Estimated Bladder Weight and Bladder Wall Thickness After Treatment of Bladder Outlet Obstruction With Dutasteride

OBJECTIVES

To investigate the change of bladder wall hypertrophy to relieve bladder outlet obstruction (BOO) by treatment with 5α-reductase inhibitor.

METHODS

Men who have BOO confirmed by urodynamic study (BOO index ≥40) were treated with dutasteride 0.5 mg once a day for 6 months. We measured ultrasound estimated bladder weight (UEBW), UEBW divided by body surface area (UEBW/BSA), and bladder wall thickness (BWT) before and after treatment. Changes in LUTS parameters were assessed by using the International Prostate Symptom Score, uroflowmetry, residual urine volume, prostate volume, serum prostate-specific antigen (PSA), and LUTS outcome scores (LOS). Correlation between the change of LUTS parameters and UEBW, UEBW/BSA, and BWT were evaluated. We assessed the changes of bladder wall hypertrophy according to the results of benefit, satisfaction, and willingness to continue (BSW) questionnaire.

RESULTS

Thirty patients completed the 6-month study. The mean UEBW was 47.10 ± 7.79 g before and 50.07 ± 5.39 g after dutasteride treatment (P = 0.259). The mean UEBW/BSA was 26.47 ± 4.30 g/m² before and 28.2 ± 3.53 g/m² after treatment (P = 0.253), and there was no definite change in mean BWT after treatment (P = 0.301). Most LUTS parameters including LOS significantly improved. Increased BOO index value was related to decreased BWT (ρ = 0.361, P = 0.049). There was no definite change in mean UEBW, UEBW/BSA, and BWT according to the results of the BSW questionnaire.

CONCLUSIONS

There was no change in UEBW, UEBW/BSA and BWT despite improving most clinical parameters suggesting BOO. The changes of bladder wall hypertrophy parameters still have limitations to directly reflect the relief of BOO.

What are the predicting factors for the therapeutic effects of dutasteride in male patients with lower urinary tract symptoms? Investigation using a urodynamic study

AIMS

We investigated predicting factors for the therapeutic effects of dutasteride in patients with lower urinary tract symptoms (LUTS) due to benign prostatic enlargement (BPE) based on a urodynamic study (UDS).

METHODS

This was a single-center, prospective study involving 120 male outpatients with LUTS. They received 0.5 mg of dutasteride per day for 12 months. IPSS, OABSS, IPSS-QOL, and UDS were used for assessing subjective and objective symptoms prior to and 12 months after administration. Patient's age, PSA level, prostate volume, IPSS, OABSS, maximum flow rate, and post-void residual urine volume, and intravesical prostatic protrusion (IPP) were set as pre-administration parameters to predict the therapeutic effect. We evaluated the relationship between these parameters and the therapeutic effects, depending on the extent of improvement of IPSS and bladder outlet obstruction (BOO).

RESULTS

A total of 104 patients with mean age of 68.9 years and mean prostate volume of 58.9 mL were included in the analysis. Thirty-two patients (30.8%) showed an insignificant IPSS improvement of <25%, while 41 patients (39.4%) showed excellent IPSS improvement of 50% or greater. On the multivariate logistic regression analysis, IPP (95% confidence interval: 0.606-0.810) was found to be the only factor related to the improvement in IPSS. Additionally, the multiple linear regression analysis demonstrated that IPP was the most powerful factor for predicting improvement of BOO (r = -0.51, P < 0.001).

CONCLUSIONS

IPP is considered a useful predictor of the therapeutic effects of dutasteride for both subjective symptoms and BOO.

The 5α-reductase inhibitor finasteride is not associated with alterations in sleep spindles in men referred for polysomnography

OBJECTIVE

Endogenous neurosteroids that potentiate the gamma-aminobutyric acid type A (GABAA ) receptor are thought to enhance the generation of sleep spindles. This study tested the hypothesis that the 5α-reductase inhibitor finasteride, an agent associated with reductions in neurosteroids, would be associated with reduced sleep spindles in men referred for polysomnography.

METHODS

Spectral analysis and spindle waveform detection were performed on electroencephalographic (EEG) sleep data in the 11-16 Hz sigma band, as well as several subranges, from 27 men taking finasteride and 27 matched comparison patients (ages 18 to 81 years).

RESULTS

No significant differences between groups were observed for spectral power or sleep spindle morphology measures, including spindle density, amplitude, duration, and integrated spindle activity.

CONCLUSIONS

Contrary to our hypothesis, these findings demonstrate that finasteride is not associated with alterations in sleep spindle range activity or spindle morphology parameters.

Combination of 5α-reductase inhibitor with combined androgen blockade (CAB) as a novel cytoreductive regimen before prostate brachytherapy: Ultra-CAB

We report a first case of using a 5α-reductase inhibitor (5ARI) and combined androgen blockade (CAB) as a cytoreductive regimen before prostate brachytherapy. Prostate volume reduction with CAB is limited to approximately 40% in most cases, making it difficult to meet anatomical constraints to perform these procedures in cases with large prostate volume. With the added administration of 5ARI, further volume reduction can be expected. Here, we describe this cytoreductive regimen used in a 63 year-old prostate cancer patient who became eligible to receive brachytherapy after dutasteride (0.5 mg daily) was added to CAB and prostate volume reduction of 57% was achieved.

Molecular effects of bioactive fraction of Curcuma mangga (DLBS4847) as a downregulator of 5α-reductase activity pathways in prostatic epithelial cells

DLBS4847 is a standardized bioactive fraction of Curcuma mangga. In this study, we used prostate cancer (PC)-3 as the cell line to study the effects of DLBS4847 on prostatic cell viability, as well as related molecular changes associated with the decreased cell number. The observation revealed that DLBS4847 inhibited the growth of PC3 cells through downregulation of the 5α-reductase (5AR) pathway. At the transcription level, 5AR1 and androgen-receptor gene expressions were downregulated in a dose-dependent manner. Furthermore, 5AR-1 and dihydrotestosterone expression were also downregulated at the protein level. A microarray study was also performed to see the effects of DLBS4847 on differential gene expressions in prostate cancer 3 cells. Among others, DLBS4847 downregulated genes related to prostate growth and hypertrophy. Our results suggested that DLBS4847 could potentially become an alternative treatment for prostate disorders, such as benign prostatic hyperplasia. In this regard, DLBS4847 exerts its growth inhibition partially through downregulation of the 5AR pathway.

Growth of LAPC4 prostate cancer xenograft tumor is insensitive to 5α-reductase inhibitor dutasteride

Intermittent androgen deprivation therapy (IADT) allows prostate cancer patients a break from the side-effects of continuous androgen deprivation therapy (ADT). Although clinical studies suggest that IADT can significantly improve patient quality of life over ADT, it has not been demonstrated to improve patient survival. Recently, increased survival has been demonstrated when 5α-reductase inhibitors have been used during the off-cycle of IADT in animal xenograft tumor models LNCaP and LuCaP35. In the current study, the sensitivity of LAPC4 xenograft tumor regrowth to the 5ARI dutasteride was determined. Tumor regrowth and gene expression changes in LAPC4 tumors were compared to the previously determined response of LNCaP and LuCaP35 xenograft tumors to 5ARI treatment during the off-cycle of IADT, LAPC4, LNCaP and LuCaP35 tumors were sensitive to androgen manipulation. However, in contrast to LNCaP and LuCaP35, dutasteride treatment during testosterone-stimulated prostate regrowth did not affect tumor regrowth or the expression of androgen responsive genes. Tumor response to dutasteride during the off-cycle of IADT is variable in xenograft prostate tumor models. Future studies will be required to elucidate the mechanisms contributing to the dutasteride resistance observed in the LAPC4 model during the off-cycle.

Key learnings from the Endocrine Disruptor Screening Program (EDSP) Tier 1 rodent uterotrophic and Hershberger assays

In 2009, companies began screening compounds using the US Environmental Protection Agency's Endocrine Disruptor Screening Program (EDSP). EDSP has two tiers: Tier 1 includes 11 assays to identify compounds with potential endocrine activity. This article describes two laboratories' experiences conducting Tier 1 uterotrophic and Hershberger assays. The uterotrophic assay detects estrogen receptor agonists through increases in uterine weight. The advantages of the uterotrophic rat models (immature vs. adult ovariectomized) and exposure routes are discussed. Across 29 studies, relative differences in uterine weights in the vehicle control group and 17α-ethynylestradiol–positive control group were reasonably reproducible. The Hershberger assay detects androgen receptor (AR) agonists, antagonists, and 5α-reductase inhibitors through changes in accessory sex tissue (AST) weights. Across 23 studies, AST weights were relatively reproducible for the vehicle groups (baseline), testosterone propionate (TP) groups (androgenic response), and flutamide + TP groups (antiandrogenic response). In one laboratory, one and four compounds were positive in the androgenic and antiandrogenic portions of the assay, respectively. Each compound was also positive for AR binding. In the other laboratory, three compounds showed potential antiandrogenic activity, but each compound was negative for AR binding and did not fit the profile for 5α-reductase inhibition. These compounds induced hepatic enzymes that enhanced testosterone metabolism/clearance, resulting in lower testosterone and decreased capacity to maintain AST weights. The Hershberger androgenic and antiandrogenic performance criteria were generally attainable. Overall, the uterotrophic and Hershberger assays were easily adopted and function as described for EDSP screening, although the mode of action for positive results may not be easily determined.

5α-Reductase inhibitor is less effective in men with small prostate volume and low serum prostatic specific antigen level

BACKGROUND/PURPOSE

Large total prostate volumes (TPVs) or high serum prostate-specific antigen (PSA) levels indicate high-risk clinical progression of benign prostatic hyperplasia. This prospective study investigated the treatment outcome of combined 5α-reductase inhibitor and α-blocker in patients with and without large TPVs or high PSA levels.

METHODS

Men aged ≥ 45 years with International Prostate Symptom scores (IPSS) ≥ 8, TPV ≥ 20 mL, and maximum flow rate ≤ 15 mL/s received a combination therapy (dutasteride plus doxaben) for 2 years. Patients with baseline PSA ≥ 4 ng/mL underwent prostatic biopsy for excluding malignancy. The changes in the parameters from baseline to 24 months after combination therapy were compared in those with and without TPV ≥ 40 mL or PSA levels ≥ 1.5 ng/mL.

RESULTS

A total of 285 patients (mean age 72 ± 9 years) completed the study. Combination therapy resulted in significant continuous improvement in IPSS, quality of life index, maximum flow rate, and postvoid residual (all p < 0.0001) regardless of baseline TPV or PSA levels. However, only patients with baseline TPV ≥ 40 mL had significant improvements in IPSS-storage subscore, voided volume, reduction in TPV, transitional zone index, and PSA levels. In addition, patients with baseline TPV < 40 mL and PSA < 1.5 ng/mL had neither a reduction in TPV nor a decrease in serum PSA level.

CONCLUSION

A high TPV indicates more outlet resistance, whereas elevated serum PSA level reflects glandular proliferation. Thus, patients with TPV<40 mL and low PSA levels has less benefit from 5α-reductase inhibitor therapy. The therapeutic effect of combined treatment may arise mainly from the α-blocker in these patients.

Risk factors for delayed hematuria following photoselective vaporization of the prostate

PURPOSE

Photoselective vaporization of the prostate has become an increasingly popular option for the treatment of benign prostatic hyperplasia. However, delayed bleeding has been raised as a potential issue as more cases are performed. We characterize delayed bleeding after photoselective vaporization of the prostate and identify associated risk factors.

MATERIALS AND METHODS

We defined delayed gross hematuria as any complaint of hematuria following hospital discharge, and further stratified it as delayed gross hematuria requiring emergency department evaluation, hospital admission, continuous bladder irrigation, transfusions or reoperation. We performed an explicit chart review of 290 patients who underwent photoselective vaporization of the prostate at a single center from 2002 through 2009. Exposures of interest included age, prostate volume, followup duration, operative factors (watts/joules), and use of oral anticoagulation therapy or 5α-reductase inhibitors.

RESULTS

Delayed gross hematuria occurred in 33.8% of patients during an average followup of 33 months. For 8.5% of patients the bleeding was severe enough to prompt presentation to the emergency department. For 4.8% of patients hospitalization was required and for 4.5% reoperation was required. Multivariate analysis revealed that the odds of bleeding increased with prostate size (OR 1.08, 1.03-1.14), longer followup (OR 1.35, 1.12-1.62) and anticoagulant use (OR 3.35, 1.43-7.83), and decreased with increasing age (OR 0.71, 0.51-0.98) and use of a 5α-reductase inhibitor (OR 0.41, 0.24-0.73).

CONCLUSIONS

Delayed hematuria occurs commonly after photoselective vaporization of the prostate but severe hematuria is rare. Larger prostate size, longer followup and use of anticoagulation were associated with a higher risk of delayed gross hematuria while preoperative 5α-reductase inhibitor use and older age were protective.

Finasteride reduces the risk of incident clinical benign prostatic hyperplasia

BACKGROUND

Despite the high prevalence of clinical benign prostatic hyperplasia (BPH) among older men, there remains a notable absence of studies focused on BPH prevention.

OBJECTIVE

To determine if finasteride prevents incident clinical BPH in healthy older men.

DESIGN, SETTING, AND PARTICIPANTS

Data for this study are from the Prostate Cancer Prevention Trial. After excluding those with a history of BPH diagnosis or treatment, or an International Prostate Symptom Score (IPSS) ≥ 8 at study entry, 9253 men were available for analysis.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary outcome was incident clinical BPH, defined as the initiation of medical treatment, surgery, or sustained, clinically significant urinary symptoms (IPSS >14). Finasteride efficacy was estimated using Cox proportional regression models to generate hazards ratios (HRs).

RESULTS AND LIMITATIONS

Mean length of follow-up was 5.3 yr. The rate of clinical BPH was 19 per 1000 person-years in the placebo arm and 11 per 1000 person-years in the finasteride arm (p<0.001). In a covariate-adjusted model, finasteride reduced the risk of incident clinical BPH by 40% (HR: 0.60; 95% confidence interval, 0.51-0.69; p<0.001). The effect of finasteride on incident clinical BPH was attenuated in men with a body mass index ≥ 30 kg/m(2) (p(interaction) = 0.04) but otherwise did not differ significantly by physical activity, age, race, current diabetes, or current smoking. The post hoc nature of the analysis is a potential study limitation.

CONCLUSIONS

Finasteride substantially reduces the risk of incident clinical BPH in healthy older men. These results should be considered in formulating recommendations for the use of finasteride to prevent prostate diseases in asymptomatic older men.

A systematic review of the effects and mechanisms of preoperative 5α-reductase inhibitors on intraoperative haemorrhage during surgery for benign prostatic hyperplasia

5α-reductase inhibitors (5α-RIs), including finasteride and dutasteride, are commonly used medical therapies for benign prostatic hyperplasia (BPH). Many studies reported that preoperative 5α-RI had impact on intraoperative haemorrhage during surgery for BPH, but it was still in controversial. So, we conducted a systematic review of the effects and mechanisms of 5α-RIs on intraoperative bleeding for BPH. MEDLINE, EMBASE, the Cochrane Controlled Trail Register of Controlled Trials and the reference lists of retrieved studies were searched in the analysis. Sixteen publications involving 15 different randomized controlled trials (RCTs) and a total of 1156 patients were used in the analysis, including 10 RCTs for finasteride and five RCTs for dutasteride. We found that preoperative finasteride treatment decreases microvessel density (MVD) in resected prostate specimens. Total blood loss, blood loss per gram of resected prostate tissue and decreases in haemoglobin were all greatly reduced in the finasteride group as compared to controls. Dutasteride appeared to have no effect on bleeding. This meta-analysis shows that preoperative finasteride treatment could decrease intraoperative haemorrhage during surgery for BPH. Preoperative dutasteride had no effect on intraoperative haemorrhage, but further high-quality prospective studies are still needed to confirm this observation.

Discovery of a novel hybrid from finasteride and epristeride as 5α-reductase inhibitor

Finasteride and epristeride both inhibit 5α-reductase with high potency via competitive and non-competitive mechanism, respectively. A new hybrid of finasteride and epristeride was designed as a new 5α-reductase inhibitor based on combination principles in medicinal chemistry. Human 5β-reductase was chosen as a plausible surrogate of 5α-reductase type II and the results indicate that although the hybrid compound possesses the main bulk of epristeride, its inhibitory mechanism is same as of finasteride. The hybrid turned out to be a potent 5α-reductase inhibitor in low IC(50) ranges.

Finasteride in the treatment of patients with benign prostatic hyperplasia: a review

Benign prostatic hyperplasia (BPH) is a complex and progressive disease common in aging men. While associated with bothersome lower urinary tract symptoms, it may also result in additional serious complications such as refractory hematuria, acute urinary retention, and BPH-related surgery. Medical therapy has been offered as an approach to halt this progression and perhaps reverse the pathophysiology of BPH. While alpha-blockers provide rapid relief in the form of improved flow rate, their effects may not reduce the overall risk of BPH-related complications. 5α-reductase inhibitors were therefore introduced to affect the underlying disease process by inhibiting the enzyme which converts testosterone to dihydrotesterone, the primary androgen involved in normal and abnormal prostate growth. Through this inhibition, prostate size is decreased, thereby reducing the risk of acute urinary retention and BPH-related surgery while providing symptom control. These effects are most pronounced in men with enlarged prostates (>25 mL) who are at the greatest risk of disease progression. This article reviews the literature for finasteride used in the treatment of BPH and provides evidence for its efficacy, safety and tolerability, applicability for combination therapy, and considerations of its effects on prostate cancer risk.

The Use of Nomograms for Selecting BPH Candidates for Dutasteride Therapy

Recent studies have discussed the benefits of medical therapy for benign prostatic hyperplasia (BPH), but have not provided physicians with the necessary tools needed to translate the information into individualized, evidence-based recommendations for clinically important questions. Nomograms can help physicians individualize their treatment decisions and predict a likely outcome by assessing the key risk factors for BPH progression.

Pharmacokinetics and pharmacodynamics of TF-505, a novel nonsteroidal 5alpha-reductase inhibitor, in normal subjects treated with single or multiple doses

AIMS

To assess the tolerability, pharmacokinetics and pharmacodynamics of a novel nonsteroidal and noncompetitive inhibitor of type I and type II 5alpha-reductases, (-)-(S)-4-[1-[4-[1-(4-isobutylphenyl) butoxy]benzoyl]indolizin-3-yl]butyric acid (TF-505), after single and multiple oral doses in healthy volunteers.

METHODS

In the single-dose study, six young adult males in each dose group received 25 mg or 50 mg of TF-505, and six older males (>or= 40 years) in each dose group received 75 mg or 100 mg of TF-505. The subjects were given the drug in ascending dose and in the fasting state. Six subjects also received 50 mg of TF-505 after breakfast in a two-period crossover manner. In the multiple-dose study, six older males in each dose group received 12.5 mg or 25 mg TF-505 after breakfast daily for 7 days. Plasma concentrations of TF-505, dihydrotestosterone (DHT) and testosterone were measured. The pharmacokinetics of TF-505 were analysed by a compartment model with first-order absorption, first-order elimination and a lag time. Pharmacokinetic and pharmacodynamic relationships were evaluated by indirect response modelling with inhibition of input.

RESULTS

Maximum plasma concentration (Cmax) and the area under the concentration-time curve (AUC) increased proportionately after the single dose up to 50 mg and with the multiple doses. Linearity was not detected between 75 and 100 mg of TF-505. Dose dependency was also noted for the effect of TF-505 on DHT concentrations following single doses up to 50 mg and multiple doses. Plasma DHT concentrations decreased maximally to 58.2, 49.5, 54.2 and 49.8% of basal values at 8-12 h after single administration of 25, 50, 75 and 100 mg TF-505, respectively, and to 60.5 and 49.4% at the 7th and 5th dose following multiple doses of 12.5 and 25 mg TF-505, respectively. The predicted effect curves matched the observed data when the indirect response model was applied to the time course of the suppressant effect of TF-505 on plasma DHT concentrations after both the single and multiple studies. Fifty percent inhibitory concentrations (IC50) of 0.82, 1.48, 1.31 and 0.88 micro g ml(-1), zero-order rate constants for the onset of plasma DHT concentration changes (kin) of 17.8, 17.4, 17.0 and 10.7% h(-1) and first-order rate constants for increase in plasma DHT concentrations to basal values (kout) of 0.17, 0.16, 0.17 and 0.10 h(-1) for the single study at doses of 25, 50, 75 and 100 mg, respectively, were attained. In the multiple-dose study, IC50s were 1.74 and 1.49 micro g ml(-1) for the 12.5 and 25 mg doses, respectively. No serious adverse events related to TF-505 were observed.

CONCLUSIONS

TF-505 was well tolerated in healthy male volunteers. Accumulation of TF-505 in plasma was not observed during multiple dosing. The indirect response model described the relationships between pharmacokinetics and pharmacodynamics of TF-505. Such modelling is expected to yield an appropriate dosage regimen in subsequent clinical trials.

The pharmacokinetic modelling of GI198745 (dutasteride), a compound with parallel linear and nonlinear elimination

AIMS

To characterize the pharmacokinetics of the dual 5alpha-reductase inhibitor GI198745 (dutasteride) to allow for more accurate predictions of GI198745 concentrations after different dosing schedules.

METHODS

In this randomized, single-blind, parallel group study, 32 healthy male volunteers received single oral doses of GI198745 ranging from 0.01 to 40 mg. Data were analysed by nonlinear mixed effects modelling using NONMEM where both linear and nonlinear pharmacokinetic models were examined.

RESULTS

The time course of GI198745 serum concentrations indicated concentration dependent elimination, with the apparent half-life increasing with dose. Data were best described by a two-compartment model with first order absorption and parallel linear and nonlinear elimination pathways. Drug absorption was rapid, and was followed by a short distribution phase. A high volume of distribution (511 l) and a low linear clearance (0.58 l h(-1)) combined to give a half-life of up to 5 (1-7) weeks at high concentrations. As concentrations declined towards Km (0.96 ng ml(-1)), the proportion eliminated by the relatively rapid saturable elimination pathway, with a maximum clearance of 6.2 l h(-1), increased and the half-life reduced to about 3 days. The estimated inter individual variability for the linear clearance was high (CV = 70%).

CONCLUSIONS

G1198745 pharmacokinetics are well described by a pharmacokinetic model with parallel linear and nonlinear elimination. Simulations using this model show that at daily doses of 0.1 mg the steady state drug concentrations, and the rate at which these are achieved, are mainly influenced by the nonlinear pathway, while at daily doses above 1 mg they are almost entirely influenced by the linear pathway.