Prostate Smooth Muscle Contraction Research Articles

Evaluation of Tamsulosin 0.4 mg versus 0.8 mg in Management of Patients Suffering from Lower Urinary Tract Symptoms Due to Benign Prostatic Hyperplasia

Abstract Introduction Lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH) are common among older men. Beside watchful waiting and surgery, medical therapy includes alpha adrenergic blockers, 5 alpha reductase inhibitors, and phytotherapy. Alpha blockers are considered to be the main treatment for BPH-associated LUTS depending on the evidence that prostatic smooth muscle contraction is responsible for bladder outlet obstruction via alpha adrenergic receptor- mediated mechanism. Tamsulosin is a super selective alpha blocker. Improvement of LUTS can be assessed by maximum flow rate (Qmax), average flow rate (Qavg), post void residual (PVR) urine volume and international prostate symptom score questionnaire (IPSS). Objectives To compare the efficacy and the safety of Tamsulosin 0.4 mg/day and 0.8 mg/day in patients suffering from lower urinary tract symptoms due to benign prostatic hyperplasia. Patients and Methods A Prospective Interventional, double-blinded, controlled study was carried out on 93 patients who met the criteria and divided randomly into 2 groups; group A for Tamsulosin 0.4 mg/day and group B for Tamsulosin 0.8 mg/day. International prostate symptom score, Post void residual urine volume, and maximum flow rate of urine were assessed before and after 4 weeks of treatment. Results Both study groups showed a significant reduction in storage sub-score but only frequency was significantly reduced in group B (P < 0.001). On the other hand, Tamsulosin 0.8 mg was superior to Tamsulosin 0.4 mg regarding voiding sub score except for straining (P = 0.325). Accordingly, the total international prostate symptom score was significantly improved in group B (P < 0.001). Furthermore, maximum flow rate and post-void residual urine volume were notably improved with Tamsulosin 0.8 mg compared to Tamsulosin 0.4 mg (P < 0.001). Although the adverse events; such as headache, orthostatic hypotension, and retrograde ejaculation were more frequent, but not significant, to occur with Tamsulosin 0.8 mg, only dizziness was noted to be significant. Conclusion Tamsulosin 0.8 mg has shown better outcomes in treating patients who suffer from lower urinary tract symptoms due to benign prostatic hyperplasia than Tamsulosin 0.4 mg, and besides that, it is well tolerated.

Leptin Mediates Prostate Stromal Cell Proliferation, Smooth Muscle Contraction, and Mitochondrial Function in Benign Prostate Hyperplasia.

Leptin is a metabolic peptide hormone produced by adipocytes, with proven roles in proliferation of prostate cancer cells and of prostate cells in animal models of benign prostatic hyperplasia (BPH). Thus, the role of leptin as a molecular link connecting BPH and lower urinary tract symptoms (LUTS) suggestive of BPH with metabolic symptoms appears feasible but is still unknown. In fact, a connection between metabolic syndrome and BPH is becoming increasingly evident from epidemiologic studies. Key factors of Lower urinary tract symptoms associated with benign prostatic hyperplasia (BPH/LUTS) are increased prostate smooth muscle tone, and prostate enlargement. Here, we examined the effects of leptin on contraction of human prostate smooth muscle and on growth of stromal cells. We performed microarray analysis to identify genes (fold change ≥ 1.5) associated with BPH/LUTS progression, such as those involved in proliferation, apoptosis, and mitochondrial metabolism, in rat prostate tissue (data from GSE129561). We then used electric field stimulation (EFS) to induce frequency-dependent, neurogenic contractions of human prostate strips, which were enhanced by leptin. We also examined the effect of leptin on human prostate stromal cells (WPMY-1) and found increased cell proliferation and viability upon exposure. To explore the underlying mechanism, we conducted mitochondrial stress assay using near-infrared (NIR) fluorescent dye and flow cytometry (FACS) analysis and observed reduced cellular apoptosis and preserved mitochondrial membrane potential (∆ψM) after leptin treatment. Microarray analysis reveals that leptin regulates prostate smooth muscle contraction and stromal cell proliferation, shedding new light on its involvement in BPH/LUTS pathogenesis and mitochondrial function. We found that leptin enhanced the proliferation rate of prostate stromal cells relative to the control group (0.67 ± 0.05 vs 0.54 ± 0.08, p-value= 0.024). Moreover, leptin (100 ng/mL) potentiated the frequency-dependent, neurogenic contractions of prostate strips elicited by EFS (p= 0.047 between leptin and control group). We also show that leptin treatment increased the mitochondrial membrane potential of prostate stromal cells and inhibited mitochondrial apoptosis. Our results indicate that leptin stimulates the contractility and proliferation of smooth muscle and stromal cells in the human prostate, implying a potential role for leptin in exacerbating BPH/LUTS in obese men. Leptin modulation may be a beneficial therapeutic strategy for patients with metabolic syndrome and BPH/LUTS. Further studies are warranted to elucidate the mechanisms and implications of the leptin system in BPH/LUTS.

Selective inhibition of neurogenic, but not agonist-induced contractions by phospholipase A2 inhibitors points to presynaptic phospholipase A2 functions in contractile neurotransmission to human prostate smooth muscle.

Phospholipases A2 (PLA2 ) may be involved in α1 -adrenergic contraction by formation of thromboxane A2 in different smooth muscle types. However, whether this mechanism occurs with α1 -adrenergic contractions of the prostate, is still unknown. While α1 -adrenoceptor antagonists are the first line option for medical treatment of voiding symptoms in benign prostatic hyperplasia (BPH), improvements are limited, probably by nonadrenergic contractions including thromboxane A2 . Here, we examined effects of PLA2 inhibitors on contractions of human prostate tissues. Prostate tissues were obtained from radical prostatectomy. Contractions were induced by electric field stimulation (EFS) and by α1 -adrenergic agonists in an organ bath, after application of the cytosolic PLA2 inhibitors ASB14780 and AACOCF3, the secretory PLA2 inhibitor YM26734, the leukotriene receptor antagonist montelukast, or of solvent to controls. Frequency-dependent contractions of human prostate tissues induced by EFS were inhibited by 25% at 8 Hz, 38% at 16 Hz and 37% at 32 Hz by ASB14780 (1 µM), and by 32% at 16 Hz and 22% at 32 Hz by AACOCF3 (10 µM). None of both inhibitors affected contractions induced by noradrenaline, phenylephrine or methoxamine. YM26734 (3 µM) and montelukast (0.3and 1 µM) neither affected EFS-induced contractions, nor contractions by α1 -adrenergic agonists, while all contractions were substantially inhibited by silodosin (100 nM). Our findings suggest presynaptic PLA2 functions in prostate smooth muscle contraction, while contractions induced by α1 -adrenergic agonists occur PLA2 -independent. Lacking sensitivity to montelukast excludes an involvement of PLA2 -derived leukotrienes in promotion of contractile neurotransmission.

PD02-03 ARF1 GEF INHIBITOR GOLGICIDE A INHIBITS ADRENERGIC AND NON-ADRENERGIC PROSTATE SMOOTH MUSCLE CONTRACTION

You have accessJournal of UrologyCME1 Apr 2023PD02-03 ARF1 GEF INHIBITOR GOLGICIDE A INHIBITS ADRENERGIC AND NON-ADRENERGIC PROSTATE SMOOTH MUSCLE CONTRACTION Alexander Tamalunas, Amin Wendt, Ru Huang, Ruixiao Wang, Yuhan Liu, Beata Rutz, Anna Ciotkowska, Giuseppe Magistro, Christian Stief, and Martin Hennenberg Alexander TamalunasAlexander Tamalunas More articles by this author , Amin WendtAmin Wendt More articles by this author , Ru HuangRu Huang More articles by this author , Ruixiao WangRuixiao Wang More articles by this author , Yuhan LiuYuhan Liu More articles by this author , Beata RutzBeata Rutz More articles by this author , Anna CiotkowskaAnna Ciotkowska More articles by this author , Giuseppe MagistroGiuseppe Magistro More articles by this author , Christian StiefChristian Stief More articles by this author , and Martin HennenbergMartin Hennenberg More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003219.03AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Prostate smooth muscle contraction is one of the main targets for medical treatment in lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH). Due to an unfavorable balance between side effects and limited efficacy, current medications cause high discontinuation rates. Agonist-induced smooth muscle contractions are mediated by activation of a1-adrenoceptors, endothelin and thromboxane, and their intracellular signaling pathways including monomeric GTPases. In general, monomeric GTPases are activated by GEFs, and deactivated by GAPs. Recently, we could show, that the small monomeric GTPase ARF6 is involved in prostate smooth muscle contraction. Here, we examined the effect of the ARF1 GEF inhibitor golgicide A on agonist-induced human prostate smooth muscle contraction. METHODS: Prostate tissues were obtained from patients undergoing radical prostatectomy for prostate cancer (n=30 patients). Contractility of prostate strips was then assessed in an organ bath. Data are presented as mean ±standard deviation, with Emax and EC50 values, while group p-value is given in the diagrams. RESULTS: Noradrenaline-induced adrenergic contractions were decreased by 47±12.1% with golgicide A (10µM) for concentrations of 1-100 µM (Figure 1A), by 30±6.6% for 1-100 µM of phenylephrine-induced contractions (Figure 1B), and by 61±10.1% for 1-100 µM of methoxamine-induced contractions (Figure 1C). Additionally, golgicide A inhibited non-adrenergic contraction by thromboxane A2 analogue U46619 by 82±19.6% for 1-300 µM of U46619-induced contractions (Figure 1D), endothelin-1 induced contraction by 53±7.0% for 1-30 µM of endothelin-1-induced contractions (Figure 1E), and EFS-induced neurogenic contractions by 76±16.6% for 2-32 Hz (Figure 1F). CONCLUSIONS: Golgicide A-sensitive GEFs are involved in regulation of human prostate smooth muscle contraction, by control of ARF1 GEF activity. Knowledge about GEFs and GAPs involved in smooth muscle contraction is still limited. However, increased understanding of prostate smooth muscle contraction may assist in developing new pharmaceutical targets for LUTS medication in the future. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e69 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Alexander Tamalunas More articles by this author Amin Wendt More articles by this author Ru Huang More articles by this author Ruixiao Wang More articles by this author Yuhan Liu More articles by this author Beata Rutz More articles by this author Anna Ciotkowska More articles by this author Giuseppe Magistro More articles by this author Christian Stief More articles by this author Martin Hennenberg More articles by this author Expand All Advertisement PDF downloadLoading ...

MP03-14 INHIBITION OF HUMAN DETRUSOR SMOOTH MUSCLE CELL GROWTH AND MODULATION OF CYTOSKELETAL ORGANIZATION BY IMMUNO-MODULATORY IMIDE DRUGS (IMIDS)

You have accessJournal of UrologyCME1 Apr 2023MP03-14 INHIBITION OF HUMAN DETRUSOR SMOOTH MUSCLE CELL GROWTH AND MODULATION OF CYTOSKELETAL ORGANIZATION BY IMMUNO-MODULATORY IMIDE DRUGS (IMIDS) Alexander Tamalunas, Amin Wendt, Florian Springer, Ru Huang, Ruixiao Wang, Yuhan Liu, Beata Rutz, Anna Ciotkowska, Giuseppe Magistro, Christian Stief, and Martin Hennenberg Alexander TamalunasAlexander Tamalunas More articles by this author , Amin WendtAmin Wendt More articles by this author , Florian SpringerFlorian Springer More articles by this author , Ru HuangRu Huang More articles by this author , Ruixiao WangRuixiao Wang More articles by this author , Yuhan LiuYuhan Liu More articles by this author , Beata RutzBeata Rutz More articles by this author , Anna CiotkowskaAnna Ciotkowska More articles by this author , Giuseppe MagistroGiuseppe Magistro More articles by this author , Christian StiefChristian Stief More articles by this author , and Martin HennenbergMartin Hennenberg More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003214.14AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: While lower urinary tract symptoms (LUTS) consist of voiding (BPH) and storage disorders (OAB), new AUA and EAU guidelines take into account the mounting number of patients suffering from both, so called “mixed LUTS”. Recently, we could show that IMiDs (thalidomide, lenalidomide and pomalidomide) inhibit prostate smooth muscle contraction, modulate cytoskeletal actin organization, and reduce prostate stromal cell growth at the same time, without showing cytotoxic effects. Based on these promising data, we now investigated the effects of IMiDs on cellular functions, including cytoskeletal organization, and growth in bladder cells. METHODS: Experiments were carried out in an immortalized line of cultured human bladder detrusor smooth muscle cells (HBdSMC). Cytoskeletal organization was visualized by phalloidin staining, while cell growth was assessed using an EdU and cell colony assay. Cell viability was quantified in CCK8 assay, and FACS. RESULTS: IMiDs ([A] thalidomide 10-100 µM, [B] lenalidomide 5-30 µM, and [C] pomalidomide 2.5-10 µM) significantly reduced the number of viable WPMY-1 cells in a concentration- and time-dependent manner (Figure 1). Correspondingly, proliferation of WPMY-1 cells was significantly reduced in a concentration-dependent manner (Figure 2 and 3), without showing pro-apoptotic effects (Figure 4). In parallel, IMiDs induced cytoskeletal disorganization: while the cellular shape of control cells was characterized by many long and thin protrusions containing bundles of actin filaments, this structure collapsed after treatment with IMiDs (Figure 5). CONCLUSIONS: IMiDs impair human detrusor smooth muscle growth, which is paralleled by a breakdown of the cytoskeleton, which may inhibit exaggerated bladder smooth muscle contraction in OAB. Urodynamic effects in vivo and a possible application in LUTS appear possible. Together with our previous data, this may suggest a possible novel drug class in LUTS treatment. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e27 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Alexander Tamalunas More articles by this author Amin Wendt More articles by this author Florian Springer More articles by this author Ru Huang More articles by this author Ruixiao Wang More articles by this author Yuhan Liu More articles by this author Beata Rutz More articles by this author Anna Ciotkowska More articles by this author Giuseppe Magistro More articles by this author Christian Stief More articles by this author Martin Hennenberg More articles by this author Expand All Advertisement PDF downloadLoading ...

Arf1 gef inhibitor golgicide a inhibits adrenergic and non-adrenergic prostate smooth muscle contraction

Arf1 gef inhibitor golgicide a inhibits adrenergic and non-adrenergic prostate smooth muscle contraction

The Effect of Long-Term Tamsulosin Monotherapy and Tamsulosin - Dutasteride Combination Therapy on PKC-α Enzyme Expression in Prostate Stromal Tissue.

The α-adrenergic receptor antagonist is the most effective medical therapy to reduce the dynamic component in patients with BPH. However, long-term administration of receptor antagonists can cause upregulation of mRNA receptor expression, resulting in tolerance of drug effectiveness. PKC-α is involved in the process of prostate smooth muscle contraction through activation of the voltage-gated Ca2+ conducted canal, influenced by androgen hormones, especially testosterone, and has an isoform with Twist1, a transcription factor that plays a role in up-regulation of androgen receptors. The aim of the study was to compare the effect of long-term tamsulosin monotherapy and tamsulosin - dutasteride combination therapy in PKC-α enzyme expression in prostate stromal tissue of Rattus norvegicus rats of Wistar strain. Out of 80 samples of Rattus norvegicus rats were divided into 8 groups with different interventions: negative control group, positive control group, tamsulosin monotherapy administration for 1 day, 3 day, and 6 day groups, and tamsulosin - dutasteride combination therapy for 1 day, 3 day, and 6 day groups. BPH was induced with 3 mg/kg of testosterone proprionate for 3 weeks, continued with drugs administration according to intervention grouping. Prostate stromal tissue was taken and prepared for PKC-α enzyme measurement with ELISA method. There was a significant difference (p<0.05) in the effect of tamsulosin monotherapy and tamsulosin-dutasteride combination therapy on the PKC-α expression. There was a strong positive relationship between the duration of tamsulosin-dutasteride combination therapy on the PKC-α expression, which means the longer the duration of the combination of tamsulosin-dutasteride combination the higher the PKC-α expression. Administration of long-term tamsulosin - dutasteride combination therapy causes upregulation PKC-α expression more than tamsulosin only.

Inhibition of α1-Adrenergic, Non-Adrenergic and Neurogenic Human Prostate Smooth Muscle Contraction and of Stromal Cell Growth by the Isoflavones Genistein and Daidzein.

Isoflavone-rich legumes, including soy, are used for food production, as dietary supplements and in traditional medicine. Soy consumption correlates negatively with benign prostatic hyperplasia (BPH) and voiding symptoms. However, isoflavone effects on the prostate are hardly known. Here, we examined the effects on human prostate smooth muscle contractions and stromal cell growth, which are driving factors of voiding symptoms in BPH. Smooth muscle contractions were induced in prostate tissues from radical prostatectomy. Growth-related functions were studied in cultured stromal cells (WPMY-1). Neurogenic, α1-adrenergic and non-adrenergic contractions were strongly inhibited with 50 µM and by around 50% with 10 µM genistein. Daidzein inhibited neurogenic contractions using 10 and 100 µM. Agonist-induced contractions were inhibited by 100 µM but not 10 µM daidzein. A combination of 6 µM genistein with 5 µM daidzein still inhibited neurogenic and agonist-induced contractions. Proliferation of WPMY-1 cells was inhibited by genistein (>50%) and daidzein (<50%). Genistein induced apoptosis and cell death (by seven-fold relative to controls), while daidzein induced cell death (6.4-fold) without apoptosis. Viability was reduced by genistein (maximum: 87%) and daidzein (62%). In conclusion, soy isoflavones exert sustained effects on prostate smooth muscle contractions and stromal cell growth, which may explain the inverse relationships between soy-rich nutrition, BPH and voiding symptoms.

Antagonism of α1-adrenoceptors by β3-adrenergic agonists: Structure–function relations of different agonists in prostate smooth muscle contraction

Effects of β3-adrenergic agonists on prostate smooth muscle contraction are poorly characterized, although mirabegron is used for treatment of lower urinary tract symptoms. Off-target effects of several β3-adrenergic agonists include antagonism of α1-adrenoceptors. Proposed, but unconfirmed explanations include phenylethanolamine backbones, found in some β3-adrenergic agonists and imparting interaction with catecholamine binding pockets of adrenoceptors. Here, we examined effects of β3-adrenergic agonists on contractions of human prostate tissues, including ZD7114 (without phenylethanolamine moiety), ZD2079 (phenylethanolamine backbone), BRL37344 and CL316243 (chloride-substituted phenylethanolamine deriatives). Prostate tissues were obtained from radical prostatectomy. Contractions by α1-adrenergic agonists and electric field stimulation (EFS) were studied in an organ bath. ZD7114 (10 µM) right-shifted concentration responses curves for α1-adrenergic agonists, resulting in increased EC50 values for phenylephrine, methoxamine and noradrenaline up to one magnitude, without affecting Emax values. ZD7114 (10 µM) inhibited EFS-induced contractions, resulting in reduced Emax values. All effects of ZD7114 were resistant to the β3-adrenergic antagonist L-748337, including increases in EC50 values for α1-adrenergic agonists, up to more than two magnitudes. Using 10 µM, neither ZD2079, BRL37344 or CL316243 affected α1-adrenergic or EFS-induced contractions. At escalated concentrations, BRL37344 (200 µM) right-shifted concentration response curves for phenylephrine, increased EC50 values for phenylephrine, and inhibited EFS-induced contractions, while CL316243 (300 µM) did not affect phenylephrine- or EFS-induced contractions. In conclusion, phenylethanolamine backbones are not decisive to impart α1-adrenoceptor antagonism to β3-agonists. Effects of β3-adrenergic agonists on prostate smooth muscle contraction are limited to off-target effects, including α1-adrenoceptor antagonism by ZD7114 and BRL37344.

A0602 - Small molecule GAP inhibitor QS11 promotes adrenergic and non-adrenergic prostate smooth muscle contraction

A0602 - Small molecule GAP inhibitor QS11 promotes adrenergic and non-adrenergic prostate smooth muscle contraction

A0598 - Pharmacological characterization of the β3-adrenoceptor agonists ZD7114, ZD2079 and BRL37344 in human prostate smooth muscle contraction

A0598 - Pharmacological characterization of the β3-adrenoceptor agonists ZD7114, ZD2079 and BRL37344 in human prostate smooth muscle contraction

A0597 - Inhibition of α1-adrenergic, non-adrenergic and neurogenic human prostate smooth muscle contraction by the isoflavone compounds genistein and puerarin

A0597 - Inhibition of α1-adrenergic, non-adrenergic and neurogenic human prostate smooth muscle contraction by the isoflavone compounds genistein and puerarin

A0601 - YM254890 inhibits prostate smooth muscle contraction by fully disrupting intracellular post-receptor signaling

A0601 - YM254890 inhibits prostate smooth muscle contraction by fully disrupting intracellular post-receptor signaling

Inhibition of human prostate smooth muscle contraction by the inhibitors of protein kinase C, GF109203X, and Go6983.

Prostate smooth muscle contraction is promoted by receptor-induced activation of intracellular signaling pathways. The presumed involvement in etiology and medical treatment of lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH) imparts a high clinical relevance to prostate smooth muscle contraction, which is contrasted by incomplete understanding at the molecular level. Involvement of protein kinase C (PKC) has been commonly assumed, but available studies were limited to nonhuman prostate smooth muscle or cell cultures. Here, we examined the effects of the PKC inhibitors Go6983 and GF109203x on contractions of human prostate tissues. Prostate tissues were obtained from radical prostatectomy. Contractions were induced by electric field stimulation (EFS), α1 -adrenergic agonists (noradrenaline, phenylephrine, methoxamine), thromboxane A2 analog U46619, endothelin-1, or calcium chloride in an organ bath. GF109203X (500 nM) and Go6983 (300 nM) reduced EFS-, noradrenaline-, phenylephrine-, methoxamine-, and U46619-induced contractions of human prostate tissues, with maximum inhibitions approaching up to 55%. Using concentrations of 3 µM, GF109203X and Go6983 inhibited EFS- and noradrenaline-induced contractions, with similar effect sizes as 500and 300 nM, respectively. Endothelin-1-induced contractions were not inhibited by GF109203X, and to neglectable extent by Go6983. After depolarization in calcium-free solution, calcium chloride-induced concentration-dependent contractions, which were inhibited by GF109203X and Go6983. GF109203X and Go6983 inhibit neurogenic, α1 -adrenergic, and thromboxane A2 -induced smooth muscle contractions in the human prostate, suggesting a role of PKC for human prostate smooth muscle contraction. The inhibition may by be imparted by inhibition of calcium sensitivity.

Mast cell function in prostate inflammation, fibrosis, and smooth muscle cell dysfunction.

Intraurethral inoculation of mice with uropathogenic Escherichia coli (CP1) results in prostate inflammation, fibrosis, and urinary dysfunction, recapitulating some but not all of the pathognomonic clinical features associated with benign prostatic hyperplasia (BPH) and lower urinary tract symptoms (LUTS). In both patients with LUTS and CP1-infected mice, we observed increased numbers and activation of mast cells and elevated levels of prostate fibrosis. Therapeutic inhibition of mast cells using a combination of a mast cell stabilizer, cromolyn sodium, and the histamine 1 receptor antagonist cetirizine di-hydrochloride in the mouse model resulted in reduced mast cell activation in the prostate and significant alleviation of urinary dysfunction. Treated mice showed reduced prostate fibrosis, less infiltration of immune cells, and decreased inflammation. In addition, as opposed to symptomatic CP1-infected mice, treated mice showed reduced myosin light chain-2 phosphorylation, a marker of prostate smooth muscle contraction. These results show that mast cells play a critical role in the pathophysiology of urinary dysfunction and may be an important therapeutic target for men with BPH/LUTS.NEW & NOTEWORTHY LUTS-associated benign prostatic hyperplasia is derived from a combination of immune activation, extracellular matrix remodeling, hyperplasia, and smooth muscle cell contraction in prostates of men. Using a mouse model, we describe the importance of mast cells in regulating these multiple facets involved in the pathophysiology of LUTS. Mast cell inhibition alleviates both pathology and urinary dysfunction in this model, suggesting the potential for mast cell inhibition as a therapeutic that prevents and reverses pathology and associated symptomology.

Phosphoproteomics identifies potential downstream targets of the integrin α2β1 inhibitor BTT-3033 in prostate stromal cells.

BackgroundIntegrin α2β1 inhibitor BTT-3033 (1-(4-fluorophenyl)-N-methyl-N-[4[[(phenylamino)carbonyl]amino]phenyl]-1H-pyrazole-4-sulfonamide) was recently reported to inhibit neurogenic and thromboxane A2-induced human prostate smooth muscle contraction, and thus represents a target with a different inhibition spectrum than that of α1-blockers in benign prostate hyperplasia (BPH) treatments. Clarifying the underlying mechanisms of the inhibition effects will provide insights into the role of integrin α2β1 in prostate contraction and enable new intracellular targets for smooth muscle contraction to be explored.MethodsProteomeHD was used to predict and enrich the top co-regulated proteins of integrin α2 (ITGA2). A phosphoproteomic analysis was conducted on human prostate stromal cells (WPMY-1) treated with 1 or 10 µM of BTT-3033 or solvent for controls. A clustering analysis was conducted to identify the intracellular targets that were inhibited in a dose-dependent manner. Gene ontology (GO) and annotation enrichments were conducted to examine any functional alterations and identify possible downstream targets. A Kinase-substrate enrichment analysis (KSEA) was conducted to identify kinases-substrate relationships.ResultsEnrichments of the actin cytoskeleton and guanosine triphosphatases (GTPases) signaling were predicted from the co-regulated proteins with ITGA2. LIM domain kinases, including LIM domain and actin-binding 1 (LIMA1), zyxin (ZYX), and thyroid receptor-interacting protein 6 (TRIP6), which are functionally associated with focal adhesions and the cytoskeleton, were present in the clusters with dose-dependent phosphorylation inhibition pattern. 15 substrates were dose-dependently inhibited according to the KSEA, including polo-like kinase 1 (PLK1), and GTPases signaling proteins, such as disheveled segment polarity protein 2 (DVL2).ConclusionsIn this study, we proposed that the mechanisms underlying the contractile and proliferative effects of integrin α2β1 are the LIM domain kinases, including the ZYX family, and substrates, including PLK1 and DVL2.

PD11-07 MIRABEGRON INHIBITS NEUROGENIC AND α 1 -ADRENERGIC HUMAN PROSTATE SMOOTH MUSCLE CONTRACTIONS, WITH SIMILAR PHARMACOLOGIC PATTERNS AS α 1 -BLOCKERS

You have accessJournal of UrologyBenign Prostatic Hyperplasia: Basic Research & Pathophysiology (PD11)1 Sep 2021PD11-07 MIRABEGRON INHIBITS NEUROGENIC AND α1-ADRENERGIC HUMAN PROSTATE SMOOTH MUSCLE CONTRACTIONS, WITH SIMILAR PHARMACOLOGIC PATTERNS AS α1-BLOCKERS Ru Huang, Yuhan Liu, Bingsheng Li, Ruixiao Wang, Alexander Tamalunas, Raphaela Waidelich, Frank Strittmatter, Christian G. Stief, and Martin Hennenberg Ru HuangRu Huang More articles by this author , Yuhan LiuYuhan Liu More articles by this author , Bingsheng LiBingsheng Li More articles by this author , Ruixiao WangRuixiao Wang More articles by this author , Alexander TamalunasAlexander Tamalunas More articles by this author , Raphaela WaidelichRaphaela Waidelich More articles by this author , Frank StrittmatterFrank Strittmatter More articles by this author , Christian G. StiefChristian G. Stief More articles by this author , and Martin HennenbergMartin Hennenberg More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000001986.07AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Mirabegron inhibits detrusor smooth muscle contractions and is available for treatment of overactive bladder. Consequently, its effects on lower urinary tract symptoms (LUTS) suggestive of bengin prostatic hyperplasia (BPH) were subject of recent trials. However, available results are not yet conclusive, and effects of mirabegron on human prostate smooth muscle contraction are hardly characterized. Voiding symptoms suggestive of BPH may be driven by increased prostate smooth muscle tone. Here, we examined effects of mirabegron on contractions of human prostate tissues. METHODS: Human prostate tissues were obtained from radical prostatectomy. Contractions were studied in an organ bath. Comparisons were performed between whole groups (one-way ANOVA), and at single frequencies and agonist concentrations (multivariate analysis). RESULTS: Electric field stimulation (EFS) induced neurogenic, frequence-dependent contractions, while agonists induced concentration-dependent contractions. Mirabegron (10 µM) inhibited EFS-induced contractions (p <0.001 for controls vs. mirabegron between whole groups), which was observed at different frequencies and reflected by reduced Emax values calculated by curve fitting (contractions in controls 84±11% of KCl-induced contractions, but 14±2% after mirabegron, p <0.01). Miragebron increased the EC50 values for noradrenaline (controls 0.55±0.32 µM, mirabegron 5.1±2.4 µM, p <0.004), resulting in rightshifts of concentration response curves for noradrenaline-induced contractions (p <0.001) and in reduced contractions up to 10 µM noradrenaline, but in recovery at higher noradrenaline concentrations and unchanged Emax values. Similarly, EC50 values for the α1-adrenergic agonist phenylephrine were increased by mirabegron (controls 7.4±4.1 µM, mirabegron 29.2±8.9 µM, p=0.05), resulting in rightshifts of concentration response curves for phenylephrine (p <0.001) and in reduced contractions up to 30 µM phenylephrine, but in recovery at higher phenylephrine concentrations and in unchanged Emax values. Mirabegron slightly reduced contractions induced by the thromboxane A2 analog U46619 (p <0.03), without changing EC50 values. Contractions induced by endothelin-1 remained unchanged by mirabegron. CONCLUSIONS: Mirabegron inhibits neurogenic and α1-adrenergic smooth muscle contractions in the human prostate. Surprisingly, the pharmacologic pattern is similar to that of α1-blockers, including rightshifts of α1-adrenergic concentration response curves, reduced Emax values for neurogenic contractions, and lacking or small effects on non-adrenergic contractions. Source of Funding: China Scholarship Council (CSC) © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e200-e200 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Ru Huang More articles by this author Yuhan Liu More articles by this author Bingsheng Li More articles by this author Ruixiao Wang More articles by this author Alexander Tamalunas More articles by this author Raphaela Waidelich More articles by this author Frank Strittmatter More articles by this author Christian G. Stief More articles by this author Martin Hennenberg More articles by this author Expand All Advertisement Loading ...

ADP Ribosylation Factor 6 Promotes Contraction and Proliferation, Suppresses Apoptosis and Is Specifically Inhibited by NAV2729 in Prostate Stromal Cells.

The presumed ADP ribosylation factor (ARF) 6 inhibitor NAV2729 inhibits human prostate smooth muscle contraction and proliferation of stromal cells, which are driving factors of voiding symptoms in benign prostatic hyperplasia (BPH). However, its specificity and a confirmed role of ARF6 for smooth muscle contraction are still pending. Here, we generated monoclonal ARF6 knockouts in human prostate stromal cells (WPMY-1), and characterized phenotypes of contractility, growth-related functions, and susceptibility to NAV2729 in knockout and control clones. ARF6 knockout was verified by Western blot. Knockout clones showed impaired contraction and actin organization, reduced proliferation and viability, and increased apoptosis and cell death. In ARF6-expressing control clones, NAV2729 (5 µM) strongly inhibited contraction (67% inhibition across all three control clones), actin organization (72%), proliferation (97%), and viability (up to 82%), and increased apoptosis (5-fold) and cell death (6-fold). In ARF6 knockouts, effects of NAV2729 (5 µM) were widely reduced, including lacking or minor effects on contractions (0% inhibition across all three knockout clones), actin (18%) and proliferation (13%), and lacking increases of apoptosis and cell death. Viability was reduced by NAV2729 with an IC50 of 3.3 µM across all three ARF6 control clones, but of 4.5-8.2 µM in ARF6 knockouts. In conclusion, ARF6 promotes prostate smooth muscle contraction and proliferation of stromal cells. Both are inhibited by NAV2729, which showed high specificity for ARF6 up to 5 µM and represents an attractive compound in the context of BPH. Considering the relevance of smooth muscle-based diseases, shared roles of ARF6 in other smooth muscle types merit further investigation. SIGNIFICANCE STATEMENT: By knockout of ARF6 in prostate stromal cells, this study demonstrates the involvement of ARF6 in promotion of prostate smooth muscle contraction and stromal growth, and defines concentration ranges for their ARF6-specific inhibition by NAV2729. Besides the context of benign prostatic hyperplasia and lower urinary tract symptoms, analog ARF6 functions in contraction and growth appear possible in other smooth muscle-rich organs, which merits further attention considering the high clinical relevance of smooth muscle-based diseases.

Lenalidomide and pomalidomide inhibit growth of prostate stromal cells and human prostate smooth muscle contraction

AimsMedical treatment for lower urinary tract symptoms secondary to benign prostatic hyperplasia is characterized by an unfavorable balance between limited efficacy and pronounced side effects. We recently reported, that thalidomide reduces prostate smooth muscle contraction and inhibits cell growth. Like thalidomide, its analogs lenalidomide and pomalidomide are also in clinical use. Therefore, we investigated the effects of lenalidomide and pomalidomide on human prostate smooth muscle contraction, cytoskeletal organization, and growth-related functions in stromal cells. Materials and methodsProliferation was assessed by EdU assay and colony formation, cytoskeletal organization by phalloidin staining, cell viability by CCK8, and apoptosis and cell death by flow cytometry in cultured prostate stromal cells (WPMY-1). Contractions of human prostate tissues from radical prostatectomy were induced by methoxamine, noradrenaline, phenylephrine, endothelin-1, U46619, or electric field stimulation (EFS) in an organ bath. Key findingsProliferation of WPMY-1 cells was significantly reduced by lenalidomide (5–200 μM) and pomalidomide (2.5–5 μM). In parallel, organization of actin filaments collapsed after treatment with lenalidomide and pomalidomide. Lenalidomide and pomalidomide inhibited both adrenergic contractions and non-adrenergic contractions as well as neurogenic contractions induced by EFS. Neither reduction in viability, nor increase in cell death or apoptosis was observed in WPMY-1 cells. SignificanceThalidomide-derivatives impair growth of human prostate stromal cells, without showing a decrease in cell viability and, in parallel, inhibit adrenergic, neurogenic, and non-adrenergic contractions by breakdown of the actin cytoskeleton. Urodynamic effects in vivo appear possible.

Concentration-dependent alpha1-Adrenoceptor Antagonism and Inhibition of Neurogenic Smooth Muscle Contraction by Mirabegron in the Human Prostate

Introduction: Mirabegron is available for treatment of storage symptoms in overactive bladder, which may be improved by β3-adrenoceptor-induced bladder smooth muscle relaxation. In addition to storage symptoms, lower urinary tract symptoms in men include obstructive symptoms attributed to benign prostatic hyperplasia, caused by increased prostate smooth muscle tone and prostate enlargement. In contrast to the bladder and storage symptoms, effects of mirabegron on prostate smooth muscle contraction and obstructive symptoms are poorly understood. Evidence from non-human smooth muscle suggested antagonism of α1-adrenoceptors as an important off-target effect of mirabegron. As α1-adrenergic contraction is crucial in pathophysiology and medical treatment of obstructive symptoms, we here examined effects of mirabegron on contractions of human prostate tissues and on proliferation of prostate stromal cells. Methods: Contractions were induced in an organ bath. Effects of mirabegron on proliferation, viability, and cAMP levels in cultured stromal cells were examined by EdU assays, CCK-8 assays and enzyme-linked immunosorbent assay. Results: Mirabegron in concentrations of 5 and 10 μM, but not 1 µM inhibited electric field stimulation-induced contractions of human prostate tissues. Mirabegron in concentrations of 5 and 10 µM shifted concentration response curves for noradrenaline-, methoxamine- and phenylephrine-induced contractions to the right, including recovery of contractions at high concentrations of α1-adrenergic agonists, increased EC50 values, but unchanged Emax values. Rightshifts of noradrenaline concentration response curves and inhibition of EFS-induced contractions were resistant to L-748,337, l-NAME, and BPIPP. 1 µM mirabegron was without effect on α1-adrenergic contractions. Endothelin-1- and U46619-induced contractions were not affected or only inhibited to neglectable extent. Effects of mirabegron (0.5–10 µM) on proliferation and viability of stromal cells were neglectable or small, reaching maximum decreases of 8% in proliferation assays and 17% in viability assays. Mirabegron did not induce detectable increases of cAMP levels in cultured stromal cells. Conclusion: Mirabegron inhibits neurogenic and α1-adrenergic human prostate smooth muscle contractions. This inhibition may be based on antagonism of α1-adrenoceptors by mirabegron, and does not include activation of β3-adrenoceptors and requires concentrations ranging 50-100fold higher than plasma concentrations reported from normal dosing. Non-adrenergic contractions and proliferation of prostate stromal cells are not inhibited by mirabegron.