Inhibition Of Smooth Muscle Contraction Research Articles

Isoform-independent promotion of contractility and proliferation, and suppression of survival by with no lysine/K kinases in prostate stromal cells.

With no lysine/K kinases (WNKs) promote vasocontraction and vascular smooth muscle cell proliferation. In the prostate, smooth muscle contraction and growth may be critical for the development and medical treatment of voiding symptoms in benign prostatic hyperplasia. Here, we examined the effects of isoform-specific WNK silencing and of the WNK inhibitor WNK463 on growth-related functions and contraction in prostate stromal cells, and in human prostate tissues. Impacts of WNK silencing by transfection of cultured stromal cells with isoform-specific siRNAs were qualitatively and quantitatively similar for each WNK isoform. Effects of silencing were largest on cell death (3-5 fold increase in annexin V-positive/7-AAD-positive cells), on proliferation rate, Ki-67 mRNA expression and actin organization (reduced around two-thirds). Contraction in matrix contraction assays and viability were reduced to a lower degree (approximately half), but again to a similar extent for each WNK isoform. Effects of silencing were quantitatively and qualitatively reproduced by 10 μM WNK463, while 1 μM still induced cell death and breakdown in actin organization, without affecting proliferation or viability. Using 500 nM and 10 μM, WNK463 partly inhibited neurogenic and U46619-induced contractions of human prostate tissues (around half), while inhibition of α1-adrenergic contractions (around half) was limited to 10 μM. All four WNK isoforms suppress cell death and promote proliferation in prostate stromal cells. WNK-driven contraction of stromal cells appears possible, even though to a limited extent. Outcomes of isoform-specific WNK silencing can be fully reproduced by WNK463, including inhibition of smooth muscle contraction in human prostate tissues, but require high concentrations.

A pharmacologically pre-contracted smooth muscle bowel model for the study of highly-potent opioid receptor agonists and antagonists

Isolated organ models are a versatile tool for pharmacological and toxicological research. Small bowel has been used to assess the inhibition of smooth muscle contraction by opioids. In the present study, we set out to establish a pharmacologically stimulated rat bowel model. The effects of carfentanil, remifentanil and the new synthetic opioid U-48800 and their respective antagonists naloxone, nalmefene and naltrexone were studied in a small bowel model in rats. The IC50 values of the tested opioids were as follows: carfentanil (IC50 = 0.02 µmol/L, CI 0.02–0.03 µmol/L) ≫ remifentanil (IC50 = 0.51 µmol/L, CI 0.40–0.66 µmol/L) ≫ U-48800 (IC50 = 1.36 µmol/L, CI 1.20–1.54 µmol/L). The administration of the opioid receptor antagonists naloxone, naltrexone and nalmefene led to progressive, parallel rightward shifts of the dose-response curves. Naltrexone was most potent in antagonizing the effects of U-48800, whereas naltrexone and nalmefene were most effective in antagonizing the effects of carfentanil. In summary, the current model seems to be a robust tool to study opioid effects in a small bowel model without the necessity of using electrical stimulation.

A0438 - Inhibition of smooth muscle contraction in isolated human detrusor tissues by mirabegron requires concentrations out of therapeutic range, and is limited to neurogenic contractions

A0438 - Inhibition of smooth muscle contraction in isolated human detrusor tissues by mirabegron requires concentrations out of therapeutic range, and is limited to neurogenic contractions

Picotamide inhibits a wide spectrum of agonist‐induced smooth muscle contractions in porcine renal interlobar and coronary arteries

Picotamide is a thromboxane A2 (TXA2) receptor antagonist and TXA2 synthase inhibitor. In clinical studies, it has been considered as a platelet aggregation inhibitor and improved renal function. In vitro studies suggested inhibition of smooth muscle contraction by picotamide, which is poorly understood. Here, we examined effects of picotamide on contractions of renal interlobar and coronary porcine arteries, induced by different vasoconstrictors. Contractions were induced in an organ bath by agonists or electric field stimulation (EFS). Picotamide inhibited EFS‐induced contractions of interlobar arteries around 50% using concentrations of 100 and 300 µM. In interlobar arteries, concentration response curves for contractions induced by three different α1‐adrenoceptor agonists were shifted to the right by picotamide (2–10‐fold increases in EC50). In coronary arteries, α1‐adrenergic contractions were inhibited without right shift (approx. 50%). Contractions induced by two different cholinergic agonists in coronary arteries were inhibited by picotamide (≥50%) withouth right shift. Inhibition of serotonin‐induced contractions by picotamide showed features of a right shift, whereas contractions induced by the TXA2 analog U46619, angiotensin‐II, and endothelin‐1 were inhibited by picotamide in interlobar and coronary arteries without right shifts and to different degree. Picotamide inhibits a wide spectrum of vasoconstrictor‐induced contractions in porcine interlobar and coronary arteries. Inhibition of vasocontraction may contribute to beneficial effects of picotamide in the cardiovascular system and kidney.

Piloleiomyoma Presented by Multiple Cutaneous Nodules: a Case Report

Abstract Introduction. Piloleiomyoma is a rare benign tumor which is caused by erector pili muscle and makes up 5% of all leiomyomas. They can be solitary and multiple. Multiple lesions still pose challenges for clinicians since their treatment option is very limited. Case report. We report a case of a 25-year-old male patient who had painful papules and nodules on the neck and chest for three years. Multiple red-brown papules and nodules in the skin of regio mammaria dextra and regio submandibularis on the left were seen on physical examination. Histopathological examination of punch bi-were seen on physical examination. Histopathological examination of punch biopsy sample revealed well-circumscribed nodule composed of spindle cells. The case was reported as cutaneous leiomyoma (piloleiomyoma). The patient was given 5 mg/day amlodipin and kept under control. Conclusion. The ideal treatment option for piloleiomyoma is surgical excision, but the problem with that treatment is that the lesions have tendency to recur. Medicamentous therapy plays a limited role; however, calcium-channel blockers and α-adrenergic blockers may help in palliating or eliminating associated pain through inhibition of smooth muscle contraction.

Se Deficiency Induced Inflammation Resulting to a Diminished Contraction of the Small Intestinal Smooth Muscle in Mice.

Selenium (Se) is an essential trace element for both humans and animals. Se deficiency leads to myocardial injury, reproductive disorder, increased exudation, inflammatory injury, and other diseases. The present study analyzed the relationships of Se deficiency, inflammation, and smooth muscle contraction in the small intestine, which is the main tissue that digests and absorbs Se. The model was established by feeding the animals diets with different concentrations of Se. The results showed that the dietary Se content was positively correlated with the blood Se concentration and the intestinal Se concentration. ROS and MPO activity increased with the lack of Se. TNF-α, IL-1β, and IL-6 expression was increased at both the mRNA and protein levels with Se deficiency. The pathways tested showed that the IκBα, NF-κB p65, p38, ERK, and JNK phosphorylation levels were significantly increased with the lack of Se. Moreover, the contractility analysis confirmed that contraction of the intestinal smooth muscle was attenuated by Se deficiency, as shown by the MedLab data acquisition system. These results further illuminated the relationship between inflammation and inhibition of smooth muscle contraction under Se deficiency in the small intestine. The Ca2+ concentration was decreased, and RhoA phosphorylation and ROCK expression were also inhibited by Se deficiency. The results also showed that MLC protein phosphorylation decreased with Se deficiency. In conclusion, the present study indicated that inflammation under Se deficiency leads to the inhibition of smooth muscle contraction in the small intestine.

MP06-10 INHIBITION OF HUMAN PROSTATE SMOOTH MUSCLE CONTRACTION BY THE INTEGRIN α2β1-SELECTIVE INHIBITOR BTT3033 AND THE INTEGRIN-LINKED KINASE INHIBITOR CPD22

You have accessJournal of UrologyBenign Prostatic Hyperplasia: Basic Research & Pathophysiology (MP06)1 Apr 2020MP06-10 INHIBITION OF HUMAN PROSTATE SMOOTH MUSCLE CONTRACTION BY THE INTEGRIN α2β1-SELECTIVE INHIBITOR BTT3033 AND THE INTEGRIN-LINKED KINASE INHIBITOR CPD22 Bingsheng Li*, Xiaolong Wang, Beata Rutz, Anna Ciotkowska, Christian Gratzke, Alexander Tamalunas, Raphaela Waidelich, Christian Stief, and Martin Hennenberg Bingsheng Li*Bingsheng Li* More articles by this author , Xiaolong WangXiaolong Wang More articles by this author , Beata RutzBeata Rutz More articles by this author , Anna CiotkowskaAnna Ciotkowska More articles by this author , Christian GratzkeChristian Gratzke More articles by this author , Alexander TamalunasAlexander Tamalunas More articles by this author , Raphaela WaidelichRaphaela Waidelich 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.0000000000000820.010AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Integrins connect the cytoskeleton of cells to membranes and extracellular matrix, what is essential for force generation by smooth muscle contraction. Suprisingly, their role for contraction has not been tested yet in any organ. In the prostate, smooth muscle contraction is critical for lower urinary tract symptoms in benign prostatic hyperplasia (BPH). Integrins are composed by different subunits in different organs, so that subunit-specific inhibitors may be attractive to attain prostate-specific inhibition of smooth muscle contraction. Here we examined effects of the integrin α2β1 inhibitor BTT3033 and the integrin-linked kinase (ILK) inhibitor Cpd22 on contractions of human prostate tissues. METHODS: Prostate tissues were obtained from radical prostatectomy (n=56 patients). Contraction of prostate strips was studied in an organ bath. Integrins and ILK were detected by Western blot and fluorescence staining. RESULTS: Electric field stimulation (EFS) induced frequency-dependent contractions of prostate tissues, which were inhibited by BTT3033 (1 µM) (55% inhibition at 32 Hz; p<0.004 for whole frequency-response curves; n=5) and Cpd22 (3 µM) (47% inhibition at 32 Hz, p<0.02, n=5). The α1-adrenoceptor agonists noradrenaline and methoxamine induced concentration-dependent, which were inhibited BTT3033 (1 µM) (p<0.004 for noradrenaline, n=5; p<0.03 for methoxamine, n=6), and by Cpd22 (3 µM) (p<0.008 for noradrenaline, n=6; p<0.02 for methoxamine, n=5). The thromboxane A2 analog U46619 induced concentration-dependent contractions, which were inhibited by BTT3033 (1 µM) (p<0.03, n=5), and by Cpd22 (p<0.001, n=5). Western blot analyses of prostate tissues revealed bands with sizes matching the expected sizes for integrin α2b, integrin β1 and ILK, which were observed in each included sample (n=9). Double fluorescence staining of prostate sections (n=5) resulted in immunoreactivity colocalizing with calponin, suggesting localization in prostate smooth muscle cells. CONCLUSIONS: Integrin and ILK inhibitors inhibit agonist-induced and neurogenic prostate smooth muscle contraction in BPH. As integrins show organ-specific composition, targeting the prostate-specific integrin code by subunit-specific inhibitors may offer a promising approach to attain inhibition in the prostate, without side effects in the cardiovascular system. Source of Funding: Deutsche Forschungsgemeinschaft (DFG), Chinese Scholarship Council (CSC) © 2020 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 203Issue Supplement 4April 2020Page: e54-e55 Advertisement Copyright & Permissions© 2020 by American Urological Association Education and Research, Inc.MetricsAuthor Information Bingsheng Li* More articles by this author Xiaolong Wang More articles by this author Beata Rutz More articles by this author Anna Ciotkowska More articles by this author Christian Gratzke More articles by this author Alexander Tamalunas More articles by this author Raphaela Waidelich More articles by this author Christian Stief More articles by this author Martin Hennenberg More articles by this author Expand All Advertisement PDF downloadLoading ...

Contraction of atrial smooth muscle reduces cardiac output in perfused turtle hearts.

Unusual undulations in resting tension (tonus waves) were described in isolated atria from freshwater turtles more than a century ago. These tonus waves were soon after married with the histological demonstration of a rich layer of smooth muscle on the luminal side of the atrial wall. Research thereafter waned and the functional significance of this smooth muscle has remained obscure. Here, we provide evidence that contraction of the smooth muscle in the atria may be able to change cardiac output in turtle hearts. In in situ perfused hearts of the red-eared slider turtle (Trachemys scripta elegans), we demonstrated that activation of smooth muscle contraction with histamine (100 nmol kg-1 bolus injected into perfusate) reduced cardiac output by decreasing stroke volume (>50% decrease in both parameters). Conversely, inhibition of smooth muscle contraction with wortmannin (10 µmoll-1 perfusion) approximately doubled baseline stroke volume and cardiac output. We suggest that atrial smooth muscle provides a unique mechanism to control cardiac filling that could be involved in the regulation of stroke volume during diving.

Spasmolytic and antidiarrheal activities of Lippia thymoides (Verbenaceae) essential oil

Lippia thymoides (‘alecrim-do-mato’ or ‘alecrim-do-campo’) is used in Brazilian folk medicine to treat various illnesses, including diarrhea. This work aimed to evaluate in vitro spasmolytic and in vivo antidiarrheal activities of the L. thymoides essential oil (OOS) and to correlate with the traditional use of this plant. In isolated guinea-pig ileum, OOS presented a concentration-dependent spasmolytic activity in preparations pre-contracted with KCl 40 mM [EC50 = 16.89 (11.56–24.66) μg/mL], and antagonized phasic contractions induced by 1 μM carbachol [IC50 = 42.71 (37.35–48.83) μg/mL] or histamine [IC50 = 32.38 (27.44–38.20) μg/mL]. In mice, OOS at 400 mg/kg reduced intestinal transit, at 200 and 400 mg/kg reduced total stool mass and at 400 mg/kg reduced intestinal fluid accumulation. It was shown that the antidiarrheal effect of OOS is related to the inhibition of smooth muscle contraction and may be due to the presence of major compound β-caryophyllene in this essential oil.

Inhibition of smooth muscle contraction and ARF6 activity by the inhibitor for cytohesin GEFs, secinH3, in the human prostate.

Prostate smooth muscle contraction is critical for etiology and treatment of male lower urinary tract symptoms (LUTS) and is promoted by small monomeric GTPases (RhoA and Rac). GTPases may be activated by guanosine nucleotide exchange factors (GEFs). GEFs of the cytohesin family may indirectly activate Rac, or ADP ribosylation factor (ARF) GTPases directly. Here we investigated the expression of cytohesin family GEFs and effects of the cytohesin inhibitor Sec7 inhibitor H3 (secinH3) on smooth muscle contraction and GTPase activities in human prostate tissues. Of all four cytohesin isoforms, cytohesin-1 and -2 showed the highest expression in real-time PCR. Western blot and fluorescence staining suggested that cytohesin-2 may be the predominant isoform in prostate smooth muscle cells. Contractions induced by norepinephrine, the α1-adrenoceptor agonist phenylephrine, the thromboxane A2 analog U-46619 , and endothelin-1 and -3, as well as neurogenic contractions induced by electric field stimulation (EFS), were reduced by secinH3 (30 µM). Inhibition of EFS-induced contractions appeared to have efficacy similar to that of inhibition by the α1-adrenoceptor antagonist tamsulosin (300 nM). Combined application of secinH3 plus tamsulosin caused larger inhibition of EFS-induced contractions than tamsulosin alone. Pull-down assays demonstrated inhibition of the small monomeric GTPase ARF6 by secinH3, but no inhibition of RhoA or Rac1. In conclusion, we suggest that a cytohesin-ARF6 pathway takes part in smooth muscle contraction. This may open attractive new possibilities in medical treatment of male LUTS.

107 - Detection of Rac activity and inhibition of smooth muscle contraction by EHT1864 in the human trigone: Expanding the role of Rac GTPase in the lower urinay tract outflow region

107 - Detection of Rac activity and inhibition of smooth muscle contraction by EHT1864 in the human trigone: Expanding the role of Rac GTPase in the lower urinay tract outflow region

994 Inhibition of smooth muscle contraction by the inhibitor for cytohesin familiy guanosine nucleotide exchange factors, secin H3 in the hyperplastic human prostate

994 Inhibition of smooth muscle contraction by the inhibitor for cytohesin familiy guanosine nucleotide exchange factors, secin H3 in the hyperplastic human prostate

Prostanoid receptors mediating contraction in rat, macaque and human bladder smooth muscle in vitro

Selective prostaglandin EP1 antagonists have been suggested for the treatment of bladder dysfunction. This study assessed the contractile prostanoid receptor subtypes in human and non-human bladder in vitro. Classical tissue bath studies were conducted using bladder strips exposed to prostanoid agonists and antagonists. Prostaglandin E2 (PGE2) contracted rat, macaque and human bladder smooth muscle strips (pEC50 7.91±0.06 (n=7), 6.40±0.13 (n=7), and 6.07±0.11 (n=5), respectively). The EP1 receptor antagonist, PF2907617 (300nM), caused a rightward shift of the PGE2 concentration–response curve in the rat bladder only (pKB 8.40±0.15, n=3). PGE2 responses in rat and macaque bladders, but not human, were antagonised by the EP3 antagonist CJ24979 (1µM). Sulprostone, a mixed EP1/EP3/FP receptor agonist, induced potent contractions of rat bladder muscle (pEC50 7.94±0.31, n=6). The FP receptor agonist, prostaglandin F2α (PGF2α), induced bladder contraction in all species tested, but with a lower potency in rat. The selective FP receptor agonist latanoprost caused potent contractions of macaque and human bladder strips only. SQ29548, a selective TP antagonist, and GW848687X, a mixed EP1/TP antagonist caused rightward shifts of the concentration–response curves to the selective TP agonist, U46619 (pKB estimates 8.53±0.07 and 7.56±0.06, n=3, respectively). Responses to U46619 were absent in rat preparations. These data suggest significant species differences exist in bladder contractile prostanoid receptor subtypes. We conclude that the EP1 subtype does not represent the best approach to the clinical treatment of bladder disorders targeting inhibition of smooth muscle contraction.

Vasoactivity of rucaparib, a PARP-1 inhibitor, is a complex process that involves myosin light chain kinase, P2 receptors, and PARP itself.

Therapeutic inhibition of poly(ADP-ribose) polymerase (PARP), as monotherapy or to supplement the potencies of other agents, is a promising strategy in cancer treatment. We previously reported that the first PARP inhibitor to enter clinical trial, rucaparib (AG014699), induced vasodilation in vivo in xenografts, potentiating response to temozolomide. We now report that rucaparib inhibits the activity of the muscle contraction mediator myosin light chain kinase (MLCK) 10-fold more potently than its commercially available inhibitor ML-9. Moreover, rucaparib produces additive relaxation above the maximal degree achievable with ML-9, suggesting that MLCK inhibition is not solely responsible for dilation. Inhibition of nitric oxide synthesis using L-NMMA also failed to impact rucaparib’s activity. Rucaparib contains the nicotinamide pharmacophore, suggesting it may inhibit other NAD+-dependent processes. NAD+ exerts P2 purinergic receptor-dependent inhibition of smooth muscle contraction. Indiscriminate blockade of the P2 purinergic receptors with suramin abrogated rucaparib-induced vasodilation in rat arterial tissue without affecting ML-9-evoked dilation, although the specific receptor subtypes responsible have not been unequivocally identified. Furthermore, dorsal window chamber and real time tumor vessel perfusion analyses in PARP-1-/- mice indicate a potential role for PARP in dilation of tumor-recruited vessels. Finally, rucaparib provoked relaxation in 70% of patient-derived tumor-associated vessels. These data provide tantalising evidence of the complexity of the mechanism underlying rucaparib-mediated vasodilation.

Interaction between hydrogen sulfide-induced sulfhydration and tyrosine nitration in the KATP channel complex

Hydrogen sulfide (H₂S) is an endogenous gaseous mediator affecting many physiological and pathophysiological conditions. Enhanced expression of H2S and reactive nitrogen/oxygen species (RNS/ROS) during inflammation alters cellular excitability via modulation of ion channel function. Sulfhydration of cysteine residues and tyrosine nitration are the posttranslational modifications induced by H₂S and RNS, respectively. The objective of this study was to define the interaction between tyrosine nitration and cysteine sulfhydration within the ATP-sensitive K(+) (KATP) channel complex, a significant target in experimental colitis. A modified biotin switch assay was performed to determine sulfhydration of the KATP channel subunits, Kir6.1, sulphonylurea 2B (SUR2B), and nitrotyrosine measured by immunoblot. NaHS (a donor of H₂S) significantly enhanced sulfhydration of SUR2B but not Kir6.1 subunit. 3-Morpholinosydnonimine (SIN-1) (a donor of peroxynitrite) induced nitration of Kir6.1 subunit but not SUR2B. Pretreatment with NaHS reduced the nitration of Kir6.1 by SIN-1 in Chinese hamster ovary cells cotransfected with the two subunits, as well as in enteric glia. Two specific mutations within SUR2B, C24S, and C1455S prevented sulfhydration by NaHS, and these mutations prevented NaHS-induced reduction in tyrosine nitration of Kir6.1. NaHS also reversed peroxynitrite-induced inhibition of smooth muscle contraction. These studies suggest that posttranslational modifications of the two subunits of the KATP channel interact to alter channel function. The studies described herein demonstrate a unique mechanism by which sulfhydration of one subunit modifies tyrosine nitration of another subunit within the same channel complex. This interaction provides a mechanistic insight on the protective effects of H₂S in inflammation.

Neolignans from Aristolochia elegans as antagonists of the neurotropic effect of scorpion venom

Ethnopharmacological relevanceThe high frequency of poisoning by sting or bite from venomous animals has begun to be a serious public health problem in Mexico where scorpion sting is the most common. Because of this, there is the need to seek active substances in plant species with an antagonistic effect against neurotropic activity of scorpion venom. The aim of this work was to demonstrate which of the compounds contained in the n-hexane extract from Aristolochia elegans roots display activity against scorpion venom. Material and methodsAntagonist activity displayed by extract, fractions and isolated compounds obtained from Aristolochia elegans was guided by the inhibition of smooth muscle contraction induced by scorpion venom (Centruroides limpidus limpidus) in a model of isolated guinea pig ileum. The neolignans obtained from this extract were isolated and analyzed by chromatographic methods including HPLC. The chemical characterization of these compounds was performed by the analysis of 1H and 13C NMR spectra. ResultsThe bio-guided chromatographic fractionation allowed us to isolate 4 known neolignans: Eupomatenoid-7 (1), licarin A (2), licarin B (3), eupomatenoid-1 (4) and other new neolignan which was characterized as 2-(3′-hydroxy-4′-methoxyphenyl)-3-methyl-5-[(E)-α-propen-γ-al]-7-methoxy-benzo [b] furan (5). This compound was named as eleganal. Compounds 1 and 2 were purified from the most active fraction AeF3 (EC50 of 149.9μg/mL, Emax of 65.66%). A doses–response analysis of eupomatenoid-7(1) and licarin A(2) allowed us to establish EC50 values (65.96μg/mL and 51.96μg/mL) respectively. ConclusionsThe antagonistic effect against Centuroides limpidus limpidus scorpion venom displayed by the n-hexane extract from Aristolochia elegans roots is due to the presence of neolignans 1–2 contained in the fraction AeF3. Chemical analysis of fraction AeF2 allowed the isolation of a new compound which was identified as 2-(3′-hydroxy-4′-methoxyphenyl)-3-methyl-5-[(E)-α-propen-γ-al]-7-methoxy-benzo[b]furan (5), denominated as eleganal.

MP19-09 NSC23766, A RAC GTPASE INHIBITOR, INHIBITS SMOOTH MUSCLE CONTRACTION IN THE HYPERPLASTIC HUMAN PROSTATE

You have accessJournal of UrologyBenign Prostatic Hyperplasia: Basic Research1 Apr 2014MP19-09 NSC23766, A RAC GTPASE INHIBITOR, INHIBITS SMOOTH MUSCLE CONTRACTION IN THE HYPERPLASTIC HUMAN PROSTATE Thomas Kunit, Andrea Schreiber, Christian Gratzke, Beata Rutz, Raphaela Waidelich, Frank Strittmatter, Christian G. Stief, and Martin Hennenberg Thomas KunitThomas Kunit More articles by this author , Andrea SchreiberAndrea Schreiber More articles by this author , Christian GratzkeChristian Gratzke More articles by this author , Beata RutzBeata Rutz 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/10.1016/j.juro.2014.02.710AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Prostate smooth muscle contraction may be critical for pathophysiology and therapy of lower urinary tract symptoms (LUTS) in patients with benign prostate hyperplasia (BPH). Although several options are available, medical therapy still remains a challenge, in particular with respect to the imminent demographic transition. Consequently, new strategies for inhibition of smooth muscle contraction in the lower urinary tract are of interest. Rac, a small monomeric GTPase, is an important regulator of smooth muscle tone outside the lower urinary tract. Here, we studied Rac inhibition and expression in the human prostate. METHODS Periurethral prostate tissues were obtained from patients undergoing radical prostatectomy (n=27). Effects of the Rac inhibitor, NSC23766 on adrenergic contraction were studied in the organ bath. Rac expression was examined by Western blot analysis, and immunofluorescence staining. RESULTS The α1-adrenoceptor agonist, phenylephrine (0.1-100 μM), induced concentration-dependent contractions of human prostate strips. NSC23766 (50 μM) inhibited phenylephrine-induced contractions (Fig.). This was significant at 0.3 μM phenylephrine (p<0.05 for NSC23766 vs. control), 1 μM (p<0.003), 3 μM (p<0.002), 10 μM (p<0.0002), and 30 μM (p<0.03). Similarly, NSC23766 (50 μM) inhibited noradrenaline-induced contractions (Fig.). This was significant at 0.3 μM (p<0.05) noreadrenaline, 1 μM (p<0.02), 3 μM (p<0.03), 10 μM (p<0.02), 30 μM (p<0.02), and 100 μM (p<0.03). In Western blot analysis revealed bands with the expected size for Rac1 in prostate tissue from each patient being included in this analysis. After immunofluorescence staining, immunoreactivity for Rac1 was observed in the prostate stroma, and in glands. Double labeling with calponin and pan-cytokeratin indicated localization in smooth muscle cells and in epithelial cells. CONCLUSIONS Rac is critical for prostate smooth muscle contraction. Regulation of smooth muscle tone in the lower urinary tract by Rac may be involved in pathophysiology of LUTS, and may represent a putative new target for therapy. © 2014FiguresReferencesRelatedDetails Volume 191Issue 4SApril 2014Page: e192 Advertisement Copyright & Permissions© 2014MetricsAuthor Information Thomas Kunit More articles by this author Andrea Schreiber More articles by this author Christian Gratzke More articles by this author Beata Rutz 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 Advertisement PDF downloadLoading ...

Evolution of CRISPs Associated with Toxicoferan-Reptilian Venom and Mammalian Reproduction

Cysteine-rich secretory proteins (CRISPs) are glycoproteins found exclusively in vertebrates and have broad diversified functions. They are hypothesized to play important roles in mammalian reproduction and in reptilian venom, where they disrupt homeostasis of the prey through several mechanisms, including among others, blockage of cyclic nucleotide-gated and voltage-gated ion channels and inhibition of smooth muscle contraction. We evaluated the molecular evolution of CRISPs in toxicoferan reptiles at both nucleotide and protein levels relative to their nonvenomous mammalian homologs. We show that the evolution of CRISP gene in these reptiles is significantly influenced by positive selection and in snakes (ω = 3.84) more than in lizards (ω = 2.33), whereas mammalian CRISPs were under strong negative selection (CRISP1 = 0.55, CRISP2 = 0.40, and CRISP3 = 0.68). The use of ancestral sequence reconstruction, mapping of mutations on the three-dimensional structure, and detailed evaluation of selection pressures suggests that the toxicoferan CRISPs underwent accelerated evolution aided by strong positive selection and directional mutagenesis, whereas their mammalian homologs are constrained by negative selection. Gene and protein-level selection analyses identified 41 positively selected sites in snakes and 14 sites in lizards. Most of these sites are located on the molecular surface (nearly 76% in snakes and 79% in lizards), whereas the backbone of the protein retains a highly conserved structural scaffold. Nearly 46% of the positively selected sites occur in the cysteine-rich domain of the protein. This directional mutagenesis, where the hotspots of mutations are found on the molecular surface and functional domains of the protein, acts as a diversifying mechanism for the exquisite biological targeting of CRISPs in toxicoferan reptiles. Finally, our analyses suggest that the evolution of toxicoferan-CRISP venoms might have been influenced by the specific predatory mechanism employed by the organism. CRISPs in Elapidae, which mostly employ neurotoxins, have experienced less positive selection pressure (ω = 2.86) compared with the "nonvenomous" colubrids (ω = 4.10) that rely on grip and constriction to capture the prey, and the Viperidae, a lineage that mostly employs haemotoxins (ω = 4.19). Relatively lower omega estimates in Anguimorph lizards (ω = 2.33) than snakes (ω = 3.84) suggests that lizards probably depend more on pace and powerful jaws for predation than venom.

Anti-histaminic, mast cell stabilizing and bronchodilator effect of hydroalcoholic extract of polyherbal compound- Bharangyadi

Bronchial asthma is a chronic inflammatory disorder of the airways associated with reversible airway obstruction and increased airway responsiveness to a variety of stimuli. An intuitive inference from this definition is that a causal relationship may exist between airway inflammation and airway hyperresponsiveness. It can be say that “airway inflammation equal to airway hyperresponsiveness”. Attachment of antigen antibody complex to the mast cell causes its disruption and release of inflammatory mediators such as histamine.To evaluate the efficacy of anti-asthmatic property of a drug, evaluation of anti-histaminic, mast cell stabilizing and bronchodilator property can be use as pharmacodynamic parameter. Bharangyadi is a polyherbal compound having Bharangi (Clerodendrum serratum), Sati (Hedychium spicatum) and Pushkarmoola (Inula racemosa) as ingredient herbs The present study aimed to evaluate the anti-asthmatic activity of an indigenous polyherbal compound Bharangyadi through various in-vitro & in-vivo experimental models.The results demonstrate that drug has potent histamine antagonism property with significant mast cell stabilizing and spasmolytic activity in the experimental animals. Compound 48/80, a potent mast cell degranulator, provoked 76% degranulation of mast cells in the control group. Ethanolic extract of Bharangyadi at the doses 500 and 1000 μg/ml protected from compound 48/80-evoked degranulation (P < 0.01) in dose dependent manner.Pre-treatment with Bharangyadi extract showed 80% & 86% protection from histamine induced bronchoconstriction in guinea pigs with 27.8% and 36.1% increase in preconvoulsion time (equal to standard drug). Screening of Histamine antagonism activity on guinea pig ileum showed that drug reduces the smooth muscle contraction in dose dependent manner. Increasing concentration of Bharangyadi extract with maximum dose of histamine (1.6μg) showed maximum inhibition at the dose of 50mg (99.78%). Inhibition of smooth muscle contraction by addition of drug in organ bath before adding histamine showed that drug has preventive type antagonism.

Epoxyaurapten inhibition of smooth muscle contraction and phosphorylation of myosin light chain by myosin light chain kinase

Epoxyaurapten is a component of coumarin, which was isolated from Aurantii Fructus Immaturus. The objective of this study was to determine the inhibition of epoxyaurapten on smooth muscle in vitro. The experiment of smooth muscle contraction directly monitored the contractions of the isolated proximal duodenum by frequency and amplitude at different epoxyaurapten concentrations and under different incubation times. The results showed that epoxyaurapten inhibited contraction in intestinal muscles in a dose- and time-dependent manner. The effects of epoxyaurapten on myosin were measured in the presence of Ca2+-calmodulin using the activities of 20 kDa myosin light chain (MLC20) phosphorylation and myosin Mg2+-ATPase. The results demonstrated that MLC20phosphorylation by myosin light chain kinase (MLCK) decreased with increasing epoxyaurapten concentration. The myosin Mg2+-ATPase activity also gradually deceased with increasing epoxyaurapten concentration. With prolonged incubation time, MLC20phosphorylation by MLCK and myosin Mg2+-ATPase activities furthered declined. The effect of epoxyaurapten on MLCK expression was measured by western blot, and the results showed that epoxyaurapten inhibited the expression of MLCK in a dose- and time-dependent manner. The findings demonstrated that epoxyaurapten could effectively attenuate the contractions of intestinal smooth muscle and therefore could be developed as a potential therapy in the future.   Key words: Epoxyaurapten, myosin light chain kinase (MLCK), 20 kDa regulating myosin light chain (MLC20), myosin Mg2+-ATPase, Aurantii Fructus Immaturus.