Enhanced prostatic Esr1+ luminal epithelial cells in the absence of SRD5A2.

Steroid 5α reductase 2 (SRD5A2) converts testosterone to dihydrotestosterone and is crucial for prostatic development. 5α reductase inhibitors (5ARI) reduce prostate size in benign prostate hyperplasia (BPH) and ameliorate lower urinary tract symptoms secondary to BPH. However, the mechanisms of 5ARI functioning are still not fully understood. Here, we used a Srd5a2-/- mouse model and employed single-cell RNA sequencing to explore the impact of SRD5A2 absence on prostate cellular heterogeneity. Significant alterations in luminal epithelial cell (LE) populations were observed, alongside an increased proportion and proliferative phenotype of estrogen receptor 1 (ESR1)+ LE2 cells, following an SRD5A2-independent ESR1 differentiation trajectory. LE2 cells exhibited enhanced estrogen response gene signatures, suggesting an alternative pathway for prostate growth when SRD5A2 is absent. Human prostate biopsy analysis revealed an inverse correlation between the expressions of SRD5A2 and LE2 markers (ESR1/PKCα), and an inverse correlation between SRD5A2 and the clinical efficiency of 5ARI. These findings provide insights into 5ARI resistance mechanisms and potential alternative therapies for BPH-related lower urinary tract symptoms. © 2024 The Pathological Society of Great Britain and Ireland.

Transcriptomic analysis of benign prostatic hyperplasia identifies critical pathways in prostatic overgrowth and 5-alpha reductase inhibitor resistance.

BACKGROUND: The medical therapy of prostatic symptoms (MTOPS) trial randomized men with symptoms of benign prostatic hyperplasia (BPH) and followed response of treatment with a 5α-reductase inhibitor (5ARI), an alpha-adrenergic receptor antagonist (α-blocker), the combination of 5ARI and α-blocker or no medical therapy (none). Medical therapy reduced risk of clinical progression by 66% but the reasons for nonresponse or loss of therapeutic response in some patients remains unresolved. Our previous work showed that prostatic glucocorticoid levels are increased in 5ARI-treated patients and that glucocorticoids can increased branching of prostate epithelia in vitro. To understand the transcriptomic changes associated with 5ARI treatment, we performed bulk RNA sequencing of BPH and control samples from patients who received 5ARI versus those that did not. Deconvolution analysis was performed to estimate cellular composition. Bulk RNA sequencing was also performed on control versus glucocorticoid-treated prostate epithelia in 3D culture to determine underlying transcriptomic changes associated with branching morphogenesis. METHOD: Surgical BPH (S-BPH) tissue was defined as benign prostatic tissue collected from the transition zone (TZ) of patients who failed medical therapy while control tissue termed Incidental BPH (I-BPH) was obtained from the TZ of men undergoing radical prostatectomy for low-volume/grade prostatic adenocarcinoma confined to the peripheral zone. S-BPH patients were divided into four subgroups: men on no medical therapy (none: n = 7), α-blocker alone (n = 10), 5ARI alone (n = 6) or combination therapy (α-blocker and 5ARI: n = 7). Control I-BPH tissue was from men on no medical therapy (none: n = 8) or on α-blocker (n = 6). A human prostatic cell line in 3D culture that buds and branches was used to identify genes involved in early prostatic growth. Snap-frozen prostatic tissue taken at the time of surgery and 3D organoids were used for RNA-seq analysis. Bulk RNAseq data were deconvoluted using CIBERSORTx. Differentially expressed genes (DEG) that were statistically significant among S-BPH, I-BPH, and during budding and branching of organoids were used for pathway analysis. RESULTS: Transcriptomic analysis between S-BPH (n = 30) and I-BPH (n = 14) using a twofold cutoff (p < 0.05) identified 377 DEG (termed BPH377) and a cutoff < 0.05 identified 3377 DEG (termed BPH3377). Within the S-BPH, the subgroups none and α-blocker were compared to patients on 5ARI to reveal 361 DEG (termed 5ARI361) that were significantly changed. Deconvolution analysis of bulk RNA seq data with a human prostate single cell data set demonstrated increased levels of mast cells, NK cells, interstitial fibroblasts, and prostate luminal cells in S-BPH versus I-BPH. Glucocorticoid (GC)-induced budding and branching of benign prostatic cells in 3D culture was compared to control organoids to identify early events in prostatic morphogenesis. GC induced 369 DEG (termed GC359) in 3D culture. STRING analysis divided the large datasets into 20-80 genes centered around a hub. In general, biological processes induced in BPH supported growth and differentiation such as chromatin modification and DNA repair, transcription, cytoskeleton, mitochondrial electron transport, ubiquitination, protein folding, and cholesterol synthesis. Identified signaling pathways were pooled to create a list of DEG that fell into seven hubs/clusters. The hub gene centrality was used to name the network including AP-1, interleukin (IL)-6, NOTCH1 and NOTCH3, NEO1, IL-13, and HDAC/KDM. All hubs showed connections to inflammation, chromatin structure, and development. The same approach was applied to 5ARI361 giving multiple networks, but the EGF and sonic hedgehog (SHH) hub was of particular interest as a developmental pathway. The BPH3377, 5ARI363, and GC359 lists were compared and 67 significantly changed DEG were identified. Common genes to the 3D culture included an IL-6 hub that connected to genes identified in BPH hubs that defined AP1, IL-6, NOTCH, NEO1, IL-13, and HDAC/KDM. CONCLUSIONS: Reduction analysis of BPH and 3D organoid culture uncovered networks previously identified in prostatic development as being reinitiated in BPH. Identification of these pathways provides insight into the failure of medical therapy for BPH and new therapeutic targets for BPH/LUTS.

Randomized Placebo-Controlled Clinical Trial of Dutasteride for Reducing Heavy Drinking in Men.

BACKGROUND: Prior studies indicate that neuroactive steroids mediate some of alcohol's effects. Dutasteride, widely used to treat benign prostatic hypertrophy, is an inhibitor of 5-alpha reductase enzymes, which play a central role in the production of 5α-reduced neuroactive steroids. The purpose of this study was to test dutasteride's tolerability and efficacy for reducing drinking. METHODS: Men (n = 142) with heavy drinking (>24 drinks per week) and a goal to either stop or reduce drinking to nonhazardous levels were randomized to placebo or 1 mg dutasteride daily for 12 weeks. We hypothesized that dutasteride-treated patients would be more successful in reducing drinking. RESULTS: Generalized linear mixed models that included baseline drinking, treatment, time and their 2-way interaction identified significant interactions of treatment-time, such that dutasteride treatment reduced drinking more than placebo. During the last month of treatment, 25% of dutasteride-treated participants had no hazardous drinking (no heavy drinking days and not more than 14 drinks per week) compared with 6% of placebo-treated participants (P = 0.006; NNT = 6). Sensitivity analysis identified baseline drinking to cope as a factor associated with larger reductions in drinking for dutasteride compared with placebo-treated participants. Dutasteride was well tolerated. Adverse events more common in the dutasteride group were stomach discomfort and reduced libido. CONCLUSION: Dutasteride 1 mg daily was efficacious in reducing the number of heavy drinking days and drinks per week in treatment-seeking men. The benefit of dutasteride compared with placebo was greatest for participants with elevated baseline drinking to cope motives.

Anti-oncogenic effects of dutasteride, a dual 5-alpha reductase inhibitor and a drug for benign prostate hyperplasia, in bladder cancer.

BACKGROUND: The incidence of bladder cancer (BCa) is approximately four times higher in men than in women. To develop effective BCa treatments, there is an urgent need to understand the differences in the BCa control mechanisms based on gender. Our recent clinical study showed that androgen suppression therapy using 5α-reductase inhibitors and androgen deprivation therapy affects BCa progression, but the underlying mechanisms are still unknown. METHODS: mRNA expression levels of the androgen receptor (AR) and SLC39A9 (membrane AR) in T24 and J82 BCa cells were evaluated by reverse transcription-PCR (RT-PCR). The effect of dutasteride, a 5α-reductase inhibitor, in BCa progression was determined in cells transfected with control and AR-overexpressing plasmids. In addition, cell viability and migration assays, RT-PCR, and western blot analysis were performed to analyze the effect of dutasteride on BCa in the presence of testosterone. Finally, steroidal 5α-reductase 1 (SRD5A1), one of the dutasteride target genes, was silenced in T24 and J82 BCa cells using control and shRNA-containing plasmids, and the oncogenic role of SRD5A1 was evaluated. RESULTS: Dutasteride treatment led to significant inhibition of the testosterone-induced increase dependent on AR and SLC39A9 in cell viability and migration of T24 and J82 BCa cells and induced alterations in the expression level of cancer progression proteins, such as metalloproteases, p21, BCL-2, NF-KB, and WNT in AR-negative BCa. Furthermore, the bioinformatic analysis showed that mRNA expression levels of SRD5A1 were significantly higher in BCa tissues than in normal paired tissues. A positive correlation between SRD5A1 expression and poor patient survival was observed in patients with BCa. Also, Dutasteride treatment reduced cell proliferation and migration via blocking the SRD5A1 in BCa. CONCLUSIONS: Dutasteride inhibited testosterone-induced BCa progression dependent on SLC39A9 in AR-negative BCa and repressed oncogenic signaling pathways, including those of metalloproteases, p21, BCL-2, NF-KB, and WNT. Our results also suggest that SRD5A1 plays a pro-oncogenic role in BCa. This work provides potential therapeutic targets for the treatment of BCa.

5-Alpha reductase inhibitors induce a prostate luminal to club cell transition in human benign prostatic hyperplasia.

Benign prostatic hyperplasia (BPH) is a progressive expansion of peri-urethral prostate tissue common in aging men. Patients with enlarged prostates are treated with 5-alpha reductase inhibitors (5ARIs) to shrink prostate volume by blocking the conversion of testosterone to dihydrotestosterone (DHT). A reduction in DHT levels can elicit atrophy and apoptosis of prostate secretory luminal cells, which results in a favorable clinical response characterized by improved lower urinary tract symptoms. However, the histologic response to 5ARI treatment is often heterogeneous across prostate acini and lower urinary tract symptoms can persist to require surgical intervention. We used two spatial profiling approaches to characterize gene expression changes across histologically normal and atrophied regions in prostates from 5ARI-treated men. Objective transcriptomic profiling using the Visium spatial gene expression platform showed that 5ARI-induced atrophy of prostate luminal cells correlated with reduced androgen receptor signaling and increased expression of urethral club cell genes including LTF, PIGR, OLFM4, SCGB1A1, and SCGB3A1. Prostate luminal cells within atrophied acini adapted to decreased DHT conditions by increasing NF-κB signaling and anti-apoptotic BCL2 expression, which may explain their survival. Using GeoMx digital spatial profiling with a probe set to assess ~18 000 RNA targets, we confirmed that atrophied acini expressing SCGB3A1 displayed higher levels of club cell markers compared with histologically normal acini with NKX3-1 expression. In addition, club-like cells within regions of 5ARI-induced atrophy closely resembled true club cells from the prostatic urethra. A comparison of histologically normal regions from 5ARI-treated men and histologically normal regions from untreated men revealed few transcriptional differences. Taken together, our results describe a heterogeneous response to 5ARI treatment where cells in atrophied acini undergo an adaptation from a prostate secretory luminal to a club cell-like state in response to 5ARI treatment. © 2021 The Pathological Society of Great Britain and Ireland.

Glucocorticoids are induced while dihydrotestosterone levels are suppressed in 5-alpha reductase inhibitor treated human benign prostate hyperplasia patients.

BACKGROUND: The development of benign prostatic hyperplasia (BPH) and medication-refractory lower urinary tract symptoms (LUTS) remain poorly understood. This study attempted to characterize the pathways associated with failure of medical therapy for BPH/LUTS. METHODS: Transitional zone tissue levels of cholesterol and steroids were measured in patients who failed medical therapy for BPH/LUTS and controls. Prostatic gene expression was measured using qPCR and BPH cells were used in organoid culture to study prostatic branching. RESULTS: BPH patients on 5-α-reductase inhibitor (5ARI) showed low levels of tissue dihydrotestosterone (DHT), increased levels of steroid 5-α-reductase type II (SRD5A2), and diminished levels of androgen receptor (AR) target genes, prostate-specific antigen (PSA), and transmembrane serine protease 2 (TMPRSS2). 5ARI raised prostatic tissue levels of glucocorticoids (GC), whereas alpha-adrenergic receptor antagonists (α-blockers) did not. Nuclear localization of GR in prostatic epithelium and stroma appeared in all patient samples. Treatment of four BPH organoid cell lines with dexamethasone, a synthetic GC, resulted in budding and branching. CONCLUSIONS: After failure of medical therapy for BPH/LUTS, 5ARI therapy continued to inhibit androgenesis but a 5ARI-induced pathway increased tissue levels of GC not seen in patients on α-blockers. GC stimulation of organoids indicated that the GC receptors are a trigger for controlling growth of prostate glands. A 5ARI-induced pathway revealed GC activation can serve as a master regulator of prostatic branching and growth.

Redirecting abiraterone metabolism to fine-tune prostate cancer anti-androgen therapy.

Abiraterone blocks androgen synthesis and prolongs survival in patients with castration-resistant prostate cancer, which is otherwise driven by intratumoral androgen synthesis. Abiraterone is metabolized in patients to Δ(4)-abiraterone (D4A), which has even greater anti-tumour activity and is structurally similar to endogenous steroidal 5α-reductase substrates, such as testosterone. Here, we show that D4A is converted to at least three 5α-reduced and three 5ß-reduced metabolites in human serum. The initial 5α-reduced metabolite, 3-keto-5α-abiraterone, is present at higher concentrations than D4A in patients with prostate cancer taking abiraterone, and is an androgen receptor agonist, which promotes prostate cancer progression. In a clinical trial of abiraterone alone, followed by abiraterone plus dutasteride (a 5α-reductase inhibitor), 3-keto-5α-abiraterone and downstream metabolites were depleted by the addition of dutasteride, while D4A concentrations rose, showing that dutasteride effectively blocks production of a tumour-promoting metabolite and permits D4A accumulation. Furthermore, dutasteride did not deplete the three 5ß-reduced metabolites, which were also clinically detectable, demonstrating the specific biochemical effects of pharmacological 5α-reductase inhibition on abiraterone metabolism. Our findings suggest a previously unappreciated and biochemically specific method of clinically fine-tuning abiraterone metabolism to optimize therapy.

Isolation and HPLC Quantitative Determination of 5α-Reductase Inhibitors from Tectona grandis L.f. Leaf Extract.

Steroid 5α-reductase plays a crucial role in catalyzing the conversion of testosterone to dihydrotestosterone, which is involved in many androgen-dependent disorders. Leaf-hexane extract from Tectona grandis L.f. has shown promise as a 5α-reductase inhibitor. The objectives of this current study were to isolate and identify 5α-reductase inhibitors from T. grandis leaves and to use them as the bioactive markers for standardization of the extract. Three terpenoid compounds, (+)-eperua-8,13-dien-15-oic acid (1), (+)-eperua-7,13-dien-15-oic acid (2), and lupeol (3), were isolated and evaluated for 5α-reductase inhibitory activity. Compounds 1 and 2 exhibited potent 5α-reductase inhibitory activity, while 3 showed weak inhibitory activity. An HPLC method for the quantitative determination of the two potent inhibitors (1 and 2), applicable for quality control of T. grandis leaf extracts, was also developed. The ethanolic extract showed a significantly higher content of 1 and 2 than found in the hexane extract, suggesting that ethanol is a preferable extraction solvent. This study is the first reported isolation of 5α-reductase inhibitors (1 and 2) from T. grandis leaves. The extraction and quality control methods that are safe and useful for further development of T. grandis leaf extract as an active ingredient for hair loss treatment products are also reported.

Finasteride interferes with prostaglandin-induced CatSper signalling in human sperm.

Ca2+ signalling controls human sperm functions necessary for successful fertilization. Multiple endocrine-disrupting chemicals have been found to activate the CatSper Ca2+ channel and thereby interfering with Ca2+ signalling in human sperm. Finasteride is prescribed to men in the fertile age to treat hair loss and its use has been associated with impaired male fertility. Due to the structural relatedness of finasteride to the endogenous CatSper ligand progesterone, this study aimed to investigate whether finasteride affects human sperm in a progestogen-like manner. The effect of finasteride on Ca2+ signalling via CatSper in human sperm was investigated in cell suspensions by single-cell imaging. Additionally, effects on sperm penetration into viscous medium and acrosome reaction were assessed. Finasteride alone caused a minor transient rise in the intracellular, free Ca2+ concentration ([Ca2+]i) at physiologically relevant concentrations. Ca2+ signals induced by PGE1 were inhibited by finasteride displaying mixed type of inhibition consistent with multiple binding sites. Finasteride did not interfere with progesterone-induced Ca2+ signalling and no effect on acrosome reaction or sperm viability was found. Finasteride significantly decreased PGE1-induced penetration into viscous medium but in concentrations above what is measured in blood and seminal fluids during regular finasteride administration. In conclusion, the use of finasteride may affect Ca2+ signalling in human sperm through an interaction with the PGE1-binding site, but to which extend it alters the chances of a successful fertilization needs further investigation. It remains to be investigated whether finasteride administration may give rise to side effects by interfering with prostaglandin signalling elsewhere in the human body.

Beneficial Effects of Human Umbilical Cord Blood Mononuclear Cells on Persistent Erectile Dysfunction After Treatment of 5-Alpha Reductase Inhibitor in Rats.

BACKGROUND: Effects of human umbilical cord blood (HUCB) as a valuable source for stem cell-based therapies have not been studied in persistent post-5-alpha reductase inhibitors (5ARI) erectile dysfunction (PPED). AIM: To determine the effect of intracavernosal injection of HUCB mononuclear cells (MNCs) on ED associated with dutasteride treatment. METHODS: Twenty five adult male Sprague-Dawley rats were divided into 5 groups (n = 5 per group): (i) control, (ii) 8-week dutasteride (0.5 mg/kg/day, in drinking water), (iii) 12-week dutasteride, (iv) 8-week dutasteride+HUCB-MNCs (1 × 106) and (v) 12-week dutasteride+HUCB-MNCs. HUCB-MNCs were administered intracavernosally after eight weeks of dutasteride treatment. Experiments were performed at 4 weeks following the injection of HUCB-MNCs. Erectile responses and isometric tension of corpus cavernosum (CC) were measured. The protein expressions of phosphodiesterase type 5 (PDE5), endothelial nitric oxide synthase (eNOS), neuronal NOS (nNOS), hypoxia-inducible factor (HIF)-1α and smooth muscle/collagen contents in penile tissue were evaluated by Western blotting, immunohistochemistry, and Masson's trichrome staining, respectively. MAIN OUTCOME: In vivo erectile function, in vitro relaxant and contractile responses of CC, protein expression and localization of PDE5, eNOS, nNOS, HIF-1α, and smooth muscle content in penile tissue. RESULTS: Erectile responses in the dutasteride-treated groups were significantly decreased compared with controls (P < .001), persisting after 4-wk of washout. HUCB-MNCs restored diminished intracavernosal pressure responses, acetylcholine-, sodium nitroprusside-, sildenafil-induced relaxations, and increased phenylephrine and electrical field stimulation (EFS)-induced contractions. Decreased EFS-induced relaxations in dutasteride-treated groups were not restored by HUCB-MNCs. Increased PDE5 and reduced nNOS expressions in dutasteride groups were restored by HUCB-MNCs in the 12-week dutasteride group. eNOS and HIF-1α protein expression and serum total and free testosterone  levels were similar among groups. HUCB-MNCs reversed the decreased smooth muscle/collagen ratio in dutasteride-treated tissues. There was a significant increase in PDE5 and HIF-1α staining in 8-week dutasteride animals. CLINICAL TRANSLATION: This study demonstrates the corrective potential of HUCB-MNCs on some persistent structural and functional deterioration caused by 5ARI treatment in rats, which may encourage further evaluation of HUCB-MNCs in men with PPED. STRENGTHS AND LIMITATIONS: Therapeutic application of intracavernosal HUCB-MNCs is a novel approach for the rat model of post-5ARI ED. Lack of serum and tissue dihydrotestosterone measurements, vehicle injections and characterization of the cells remain limitations of our study. CONCLUSION: The persistent ED after prolonged administration of dutasteride in rats is reversed by HUCB-MNC treatment, which holds promise as a realistic therapeutic modality for this type of ED. Oztekin CV, Yilmaz-Oral D, Kaya-Sezginer E, et al. Beneficial Effects of Human Umbilical Cord Blood Mononuclear Cells on Persistent Erectile Dysfunction After Treatment of 5-Alpha Reductase Inhibitor in Rats. J Sex Med 2021;18:889-899.

Cardiac and Brainstem Neuroinflammatory Pathways Account for Androgenic Incitement of Cardiovascular and Autonomic Manifestations in Endotoxic Male Rats.

ABSTRACT: Inconsistent reports are available on the role of testosterone in end-organ damage caused by endotoxemia. Here, pharmacologic, surgical, and molecular studies were employed to assess the testosterone modulation of cardiovascular, autonomic, and peripheral and central inflammatory derangements caused by endotoxemia. Studies were performed in conscious male rats preinstrumented with femoral indwelling catheters for the measurement of blood pressure and subjected to castration or pharmacologic interventions that interrupt the biosynthetic cascade of testosterone. Compared with the effects of lipopolysaccharide (10 mg/kg intravenously) in sham operated rats, 2-week castration reduced the lipopolysaccharide-evoked (1) falls in blood pressure, (2) decreases in time- and frequency-domain indices of heart rate variability, (3) shifts in spectral measures of cardiac sympathovagal balance toward parasympathetic dominance, and (4) increases in protein expressions of toll-like receptor-4 and monocyte chemoattractant protein-1 in heart and medullary neurons of the nucleus tractus solitarius and rostral ventrolateral medulla. While the ameliorating actions of castration on endotoxic cardiovascular manifestations were maintained after testosterone replacement, the concomitant inflammatory signals were restored to near-sham levels. The favorable influences of castration on inflammatory and cardiovascular abnormalities of endotoxemia were replicated in intact rats pretreated with degarelix (gonadotropin-releasing hormone receptor blocker) or finasteride (5α-reductase inhibitor) but not formestane (aromatase inhibitor). The data signifies the importance of androgens and its biosynthetic enzymes in cardiovascular and autonomic insults induced by the endotoxic inflammatory response. Clinically, the interruption of testosterone biosynthesis could offer a potential strategy for endotoxemia management.

Conversion of abiraterone to D4A drives anti-tumour activity in prostate cancer.

Prostate cancer resistance to castration occurs because tumours acquire the metabolic capability of converting precursor steroids to 5α-dihydrotestosterone (DHT), promoting signalling by the androgen receptor and the development of castration-resistant prostate cancer. Essential for resistance, DHT synthesis from adrenal precursor steroids or possibly from de novo synthesis from cholesterol commonly requires enzymatic reactions by 3ß-hydroxysteroid dehydrogenase (3ßHSD), steroid-5α-reductase (SRD5A) and 17ß-hydroxysteroid dehydrogenase (17ßHSD) isoenzymes. Abiraterone, a steroidal 17α-hydroxylase/17,20-lyase (CYP17A1) inhibitor, blocks this synthetic process and prolongs survival. We hypothesized that abiraterone is converted by an enzyme to the more active Δ(4)-abiraterone (D4A), which blocks multiple steroidogenic enzymes and antagonizes the androgen receptor, providing an additional explanation for abiraterone's clinical activity. Here we show that abiraterone is converted to D4A in mice and patients with prostate cancer. D4A inhibits CYP17A1, 3ßHSD and SRD5A, which are required for DHT synthesis. Furthermore, competitive androgen receptor antagonism by D4A is comparable to the potent antagonist enzalutamide. D4A also has more potent anti-tumour activity against xenograft tumours than abiraterone. Our findings suggest an additional explanation-conversion to a more active agent-for abiraterone's survival extension. We propose that direct treatment with D4A would be more clinically effective than abiraterone treatment.

Development of a Liquid Chromatography/Mass Spectrometry-Based Inhibition Assay for the Screening of Steroid 5-α Reductase in Human and Fish Cell Lines.

Steroid 5-α reductase (5AR) is responsible for the reduction of steroids to 5-α reduced metabolites, such as the reduction of testosterone to 5-α dihydrotestosterone (DHT). A new adverse outcome pathway (AOP) for 5AR inhibition to reduce female reproduction in fish (AOP 289) is under development to clarify the antiestrogenic effects of 5AR inhibitors in female fish. A sensitive method for the DHT analysis using chemical derivatization and liquid chromatography-tandem mass spectrometry was developed. A cell-based 5AR inhibition assay that utilizes human cell lines, a transient overexpression system, and fish cell lines was developed. The measured IC50 values of two well-known 5AR inhibitors, finasteride and dutasteride, were comparable in the different systems. However, the IC50 of dutasteride in the fish cell lines was lower than that in the human cell lines. Finasteride showed a higher IC50 against the RTG-2 cell line. These results demonstrated that 5ARs inhibition could differ in terms of structural characteristics among species. The assay has high sensitivity and reproducibility and is suitable for the application in 5AR inhibition screening for various endocrine disruption chemicals (EDCs). Future studies will continue to evaluate the quantitative inhibition of 5AR by EDCs to compare the endocrine-disrupting pathway in different species.

The antiandrogenic effect of neferine, liensinine, and isoliensinine by inhibiting 5-α-reductase and androgen receptor expression via PI3K/AKT signaling pathway in prostate cancer.

Neferine, liensinine, and isoliensinine are bisbenzylisoquinoline alkaloids extracted from seed-embryos of Nelumbo nucifera Gaertn. In this study, we evaluated the anticancer activities and mechanism of action of these natural products in prostate cancer cells by MTT, wound healing, ELISA and Western blotting. Neferine, liensinine, and isoliensinine showed growth inhibition and displayed a significant anti-migration activity in prostate cancer cells. They induced apoptosis and autophagy by activating cleaved caspase-9, cleaved PAPR, Bax, LC3B-II, but decreased Bcl-2 and PARP protein expression in LNCaP cells 24 h after treatments. The apoptotic and cytotoxic effects of neferine, liensinine, and isoliensinine were significantly attenuated in the presence of the caspase inhibitor, Z-VAD-FMK. However, the effects were enhanced in the presence of Akt inhibitor (MK2206) and PI3K inhibitor (LY294002). Moreover, neferine, liensinine, and isoliensinine also downregulated the protein expression of androgen receptor, prostate-specific antigen, and type II 5-α-reductase. These results demonstrated that these bisbenzylisoquinoline alkaloids have the potential as promising therapeutics agents. They induced apoptosis via inactivation with the PI3K/AKT signal pathway.

Effects of dutasteride in a rat model of chemically induced prostatic inflammation-Potential role of estrogen receptor ß.

BACKGROUND: Dutasteride administration reportedly improves lower urinary tract symptoms in patient with chronic, histologically-identified prostatic inflammation, potentially through estrogen receptor ß (ERß), activation of which has anti-inflammatory effects in the prostate tissue. Therefore, we investigated the effect of dutasteride on intraprostatic inflammatory responses and bladder activity using a rat model of chemically induced prostatic inflammation. METHODS: Male Sprague-Dawley rats at 10 weeks old were used. Prostatic inflammation was induced by 5% formalin injection into ventral lobes of the prostate and saline was injected in the control group (control, n = 5). Rats with prostatic inflammation were divided into dutasteride therapy (dutasteride, n = 5) and placebo groups (placebo, n = 5). Dutasteride was administrated at a dose of 0.5 mg/kg daily from 2 days before induction of prostatic inflammation whereas placebo rats received vehicle only. Twenty-eight days later, cystometry was performed in a conscious condition to measure non-voiding contractions (NVCs), intercontraction intervals (ICI) and postvoid residual volume (RV). After cystometry, the prostate was excised for analysis of messenger RNA (mRNA) expression levels of ERα, ERß, interleukin-1ß (IL-1ß), and IL-18 by quantitative polymerase chain reaction. RESULTS: The mean number of NVCs was significantly greater in placebo group than that of control group without prostatic inflammation (p < .05), and ICI were significantly decreased in placebo group compared with control group (p < .05). On the contrary, there was no significant change in NVCs or ICI between control and dutasteride groups. RV was not significantly different among three groups. Gene expression levels of ERα, IL-1ß, and IL-18 was significantly increased in placebo rats compared with control rats (p < .05), but not significantly different between control and dutasteride rats. On the other hand, the mRNA expression level of ERß was significantly decreased in placebo rats (p < .05), but not in dutasteride rats, compared with control rats. CONCLUSION: Dutasteride treatment improved not only prostatic inflammation evident as increased gene expression levels in IL-1ß and IL-18, but also bladder overactivity shown by increased NVCs during bladder filling. These therapeutic effects were associated with the restored expression of anti-inflammatory ERß. Therefore, dutasteride might be effective via ERß modulation for the treatment of prostatic inflammation in addition to its previously known, anti-androgenic effects on benign prostatic hyperplasia.

Nucleus-specific modulation of phasic and tonic inhibition by endogenous neurosteroidogenesis in the murine thalamus.

Neurosteroids are potent allosteric modulators of GABAA receptors (GABAA Rs). Although the effects of exogenous neurosteroids on GABAA R function are well documented, less is known about effects of neurosteroids produced by local endogenous biosynthesis. The neurosteroidogenic enzymes 5α-reductase and 3α-hydroxysteroid dehydrogenase are expressed in two nuclei of somatosensory thalamus, the thalamic reticular nucleus (nRT) and ventrobasal nucleus (VB). Here, the effects of acute blockade of neurosteroidogenesis by the 5α-reductase inhibitor finasteride on phasic and tonic GABAA R-mediated currents were examined in nRT and VB of mice. In nRT, finasteride altered the decay and amplitude, but not the frequency, of phasic currents, with no effect on tonic inhibition. In VB neurons, by contrast, finasteride reduced both the size and frequency of phasic currents, and also reduced the degree of tonic inhibition. These studies thus provide novel evidence for endogenous modulation of GABAA R function by 5α-reduced neurosteroids in the mature thalamus.

Benzothiazepines, diltiazem and JTV-519, exert an anxiolytic-like effect via neurosteroid biosynthesis in mice.

We investigated whether benzothiazepines could produce anxiolytic effects via allopregnanolone (ALLO) biosynthesis in mice. We compared the behavioral effects caused by benzothiazepines to those caused by carbamazepine and sodium valproate. We found that a pretreatment with finasteride (a 5 alpha-reductase inhibitor) suppressed carbamazepine-induced anxiolytic effects but not the effects of sodium valproate. Similar to carbamazepine, diltiazem and JTV-519 displayed anxiolytic effects that were suppressed by a pretreatment with finasteride. We clearly demonstrate that the benzothiazepines, diltiazem and JTV-519, exert an anxiolytic-like effect via ALLO biosynthesis in mice.

Quintaquinone, a Merosesquiterpene from the Yellow Sponge Verongula cf. rigida Esper.

A chemical investigation of the sponge Verongula cf. rigida led to the isolation of 13 merosesquiterpenes, among which quintaquinone (2), 5-epi-nakijiquinone L (3), and 3-farnesyl-2-hydroxy-5-methoxyquinone (4) were isolated and reported here for the first time. Particularly, compound 2 is the first member of merosesquiterpenes with a polyketide side chain substituted on C-19. All of the isolated compounds were examined for steroid 5α-reductase inhibitory activity. Cyclospongiaquinone 1 (5) showed a strong activity in the same range as that of standard finasteride.

Taxifolin Inhibits Neurosteroidogenic Rat Steroid 5α-Reductase 1 and 3α-Hydroxysteroid Dehydrogenase.

AIMS: Taxifolin, a flavonoid, has several pharmacological activities. Taxifolin inhibits some steroid biosynthetic enzymes, suggesting that it might inhibit neurosteroid synthesis. Here, we investigated effects of taxifolin on rat neurosteroidogenic enzymes, steroid 5α-reductase 1 -(SRD5A1), 3α-hydroxysteroid dehydrogenase (AKR1C9), and retinol dehydrogenase 2 (RDH2). METHODS: SRD5A1, AKR1C9, and RDH2 were expressed in COS-1 cells and the direct effects of taxifolin on these enzymes and the mode of action were determined using steroid substrates and thin chromatography separation-coupled radiometric scanning. RESULTS: The half maximal inhibitory concentration values of taxifolin on SRD5A1 and AKR1C9 were 100 and 1.01 mol/L. Taxifolin did not inhibit RDH2 even at as high as 100 mol/L. Taxifolin competitively inhibited rat AKR1C9 against steroid dihydrotestosterone (DHT), and docking analysis revealed that taxifolin bound to the steroid binding site of rat AKR1C9 with similar free energy with the substrate DHT. CONCLUSION: Taxifolin is a potent inhibitor of rat AKR1C9 and moderate inhibitor of rat SRD5A1, thereby controlling the rate of neurosteroid biosynthesis.

Inflammatory pathway employed by Red Maca to treat induced benign prostatic hyperplasia in rats.

Benign prostatic hyperplasia (BPH) is a pathology characterised by an increase in prostate size associated with low urinary tract symptoms. Finasteride (F), a 5a-reductase inhibitor, is the standard treatment for BPH reducing prostate weight but also sexual desire. The Peruvian plant known as Red Maca (RM) (Lepidium meyenii) inhibits BPH in rats and mice. The aim of the study was to assess the inflammatory effect of RM and finasteride in rats with testosterone enanthate (TE)-induced BPH. Thirty rats were divided into 5 groups: Control, TE (50 mg/rat), TE + F (0.6 mg/kg), and two groups of TE + RM 40/80 (40 or 80 mg). After treatments, tumour necrosis factor alpha (TNFa), interleukin 4 (IL4) and interferon gamma (INFg) as well as testosterone and oestradiol were evaluated and inflammatory cells (neutrophils, mast cells and lymphocytes) in prostate were quantified. Red Maca and finasteride treatments decreased inflammatory cells counts in prostate, inhibiting TNFa by different pathways. Finasteride increased IL4 whereas Red Maca increased INFg. In conclusion, data suggest that finasteride acts on Th2 response by increasing IL4 in prostate, while Red Maca acts on Th1 response mediated by INFg.