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Sample records for tyrosyl-dna phosphodiesterase tdp1

  1. The Tyrosyl-DNA Phosphodiesterase 1β (Tdp1β Gene Discloses an Early Response to Abiotic Stresses

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    Maria Elisa Sabatini

    2017-11-01

    Full Text Available Tyrosyl-DNA phosphodiesterase 1 (Tdp1 is involved in DNA repair pathways as it mends the topoisomerase I—DNA covalent complexes. In plants, a small Tdp1 gene family, composed by Tdp1α and Tdp1β genes, was identified, but the roles of these genes in abiotic stress responses are not fully understood. To investigate their specific stress response patterns, the present study made use of bioinformatic and molecular tools to look into the Tdp1β gene function, so far described only in the plant kingdom, and compare it with Tdp1α gene coding for the canonical, highly conserved α isoform. The expression profiles of Tdp1α and Tdp1β genes were examined under abiotic stress conditions (cold, heat, high osmolarity, salt, and UV-B in two model species, Arabidopsis thaliana and Medicago truncatula. The two isoforms of topoisomerase I (TOP1α and TOP1β were also taken into consideration in view of their known roles in DNA metabolism and cell proliferation. Data relative to gene expression in Arabidopsis were retrieved from the AtGenExpress microarray dataset, while quantitative Real-Time PCR was carried out to evaluate the stress response in M. truncatula cell cultures. These analyses revealed that Tdp1β gene expression was enhanced during the first hour of treatment, whereas Tdp1α enhanced expression succeeded at subsequent timepoints. In agreement with the gene-specific responses to abiotic stress conditions, the promoter regions of Tdp1α and Tdp1β genes are well equipped with stress-related cis-elements. An in-depth bioinformatic characterization of the HIRAN motif, a distinctive feature of the Tdp1β protein, showed its wide distribution in chromatin remodeling and DNA repair proteins. The reported data suggests that Tdp1β functions in the early response to abiotic stresses.

  2. The Human Tyrosyl-DNA Phosphodiesterase 1 (hTdp1) Inhibitor NSC120686 as an Exploratory Tool to Investigate Plant Tdp1 Genes.

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    Macovei, Anca; Pagano, Andrea; Sabatini, Maria Elisa; Grandi, Sofia; Balestrazzi, Alma

    2018-03-28

    The hTdp1 (human tyrosyl-DNA phosphodiesterase 1) inhibitor NSC120686 has been used, along with topoisomerase inhibitors, as a pharmacophoric model to restrain the Tdp1 activity as part of a synergistic treatment for cancer. While this compound has an end-point application in medical research, in plants, its application has not been considered so far. The originality of our study consists in the use of hTdp1 inhibitor in Medicago truncatula cells, which, unlike human cells, contain two Tdp1 genes. Hence, the purpose of this study was to test the hTdp1 inhibitor NSC120686 as an exploratory tool to investigate the plant Tdp1 genes, since their characterization is still in incipient phases. To do so, M. truncatula calli were exposed to increasing (75, 150, 300 μM) concentrations of NSC120686. The levels of cell mortality and DNA damage, measured via diffusion assay and comet assay, respectively, were significantly increased when the highest doses were used, indicative of a cytotoxic and genotoxic threshold. In addition, the NSC120686-treated calli and untreated MtTdp1α -depleted calli shared a similar response in terms of programmed cell death (PCD)/necrosis and DNA damage. Interestingly, the expression profiles of MtTdp1α and MtTdp1β genes were differently affected by the NSC120686 treatment, as MtTdp1α was upregulated while MtTdp1β was downregulated. The NSC120686 treatment affected not only the MtTdp1 genes but also other genes with roles in alternative DNA repair pathways. Since the expression patterns of these genes were different than what was observed in the MtTdp1α -depleted plants, it could be hypothesized that the NSC120686 treatment exerts a different influence compared to that resulting from the lack of the MtTdp1α gene function.

  3. Combining a nanosensor and ELISA for measurement of tyrosyl-dna phosphodiesterase 1 (tdp1) activity and protein amount in cell and tissue extract

    DEFF Research Database (Denmark)

    Jakobsen, Ann-Katrine; Stougaard, Magnus

    2015-01-01

    be combined with ELISA measurement into one assay facilitating measurement of both the enzymatic activity and the protein amount of TDP1. We show that the combined assay can be used for measurements both in cell line-based studies and for measurement in clinical tissue samples. Due to all measurements being...... performed in the exact same aliquot of cell or tissue extract, the combined assay allows the use of minimal amount of cells or tissue and without additional incubation steps compared to the normal ELISA procedure. Measuring protein amount and activity within the same portion of extract also minimizes...... the risk of variation being introduced when comparing amount to activity. Since the assay only uses small amounts of extract, it requires no advanced equipment besides a plate reader, and can work in whole-cell or tissue extract. We expect that it could be useful for analysis of posttranslational...

  4. Dysregulated human Tyrosyl-DNA phosphodiesterase I acts as cellular toxin

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    Cuya, Selma M.; Comeaux, Evan Q.; Wanzeck, Keith; Yoon, Karina J.; van Waardenburg, Robert C.A.M.

    2016-01-01

    Tyrosyl-DNA phosphodiesterase I (TDP1) hydrolyzes the drug-stabilized 3’phospho-tyrosyl bond formed between DNA topoisomerase I (TOPO1) and DNA. TDP1-mediated hydrolysis uses a nucleophilic histidine (Hisnuc) and a general acid/base histidine (Hisgab). A Tdp1Hisgab to Arg mutant identified in patients with the autosomal recessive neurodegenerative disease SCAN1 causes stabilization of the TDP1-DNA intermediate. Based on our previously reported Hisgab-substitutions inducing yeast toxicity (Gajewski et al. J. Mol. Biol. 415, 741-758, 2012), we propose that converting TDP1 into a cellular poison by stabilizing the covalent enzyme-DNA intermediate is a novel therapeutic strategy for cancer treatment. Here, we analyzed the toxic effects of two TDP1 catalytic mutants in HEK293 cells. Expression of human Tdp1HisnucAla and Tdp1HisgabAsn mutants results in stabilization of the covalent TDP1-DNA intermediate and induces cytotoxicity. Moreover, these mutants display reduced in vitro catalytic activity compared to wild type. Co-treatment of Tdp1mutant with topotecan shows more than additive cytotoxicity. Overall, these results support the hypothesis that stabilization of the TDP1-DNA covalent intermediate is a potential anti-cancer therapeutic strategy. PMID:27893431

  5. Tyrosyl-DNA Phosphodiesterase I a critical survival factor for neuronal development and homeostasis.

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    van Waardenburg, Robert C A M

    2016-01-01

    Tyrosyl-DNA phosphodiesterase I (TDP1), like most DNA repair associated proteins, is not essential for cell viability. However, dysfunctioning TDP1 or ATM (ataxia telangiectasia mutated) results in autosomal recessive neuropathology with similar phenotypes, including cerebellar atrophy. Dual inactivation of TDP1 and ATM causes synthetic lethality. A TDP1H 493 R catalytic mutant is associated with spinocerebellar ataxia with axonal neuropathy (SCAN1), and stabilizes the TDP1 catalytic obligatory enzyme-DNA covalent complex. The ATM kinase activates proteins early on in response to DNA damage. Tdp1-/- and Atm-/- mice exhibit accumulation of DNA topoisomerase I-DNA covalent complexes (TOPO1-cc) explicitly in neuronal tissue during development. TDP1 resolves 3'- and 5'-DNA adducts including trapped TOPO1-cc and TOPO1 protease resistant peptide-DNA complex. ATM appears to regulate the response to TOPO1-cc via a noncanonical function by regulating SUMO/ubiquitin-mediated TOPO1 degradation. In conclusion, TDP1 and ATM are critical factors for neuronal cell viability via two independent but cooperative pathways.

  6. Correlation between topoisomerase I and tyrosyl-DNA phosphodiesterase 1 activities in non-small cell lung cancer tissue

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    Jakobsen, Ann-Katrine; Lauridsen, Kristina Lystlund; Samuel, Evelyn Benuja

    2015-01-01

    Topoisomerase I (TOP1) regulates DNA topology during replication and transcription whereas tyrosyl-DNA phosphodiesterase 1 (TDP1) is involved in the repair of several types of DNA damages, including damages from defective TOP1 catalysis. TOP1 is the target of chemotherapeutic drugs of the camptot......Topoisomerase I (TOP1) regulates DNA topology during replication and transcription whereas tyrosyl-DNA phosphodiesterase 1 (TDP1) is involved in the repair of several types of DNA damages, including damages from defective TOP1 catalysis. TOP1 is the target of chemotherapeutic drugs...... of the camptothecin family (CPT). TDP1 has in cell line based assays been shown to counteract the effect of CPT. We have quantified the enzymatic activities of TOP1 and TDP1 in paired (tumor and adjacent non-tumor) samples from non-small cell lung cancer (NSCLC) patients and show that in NSCLC TOP1 and TDP1...... activities are significantly upregulated in the tumor tissue. Furthermore, we found a positive correlation between the TDP1 activity and the tumor percentage (TOP1 activity did not correlate with the tumor percentage) as well as between the activities of TOP1 and TDP1 both within the tumor and the non...

  7. Tyrosyl-DNA Phosphodiesterase I Catalytic Mutants Reveal an Alternative Nucleophile That Can Catalyze Substrate Cleavage*

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    Comeaux, Evan Q.; Cuya, Selma M.; Kojima, Kyoko; Jafari, Nauzanene; Wanzeck, Keith C.; Mobley, James A.; Bjornsti, Mary-Ann; van Waardenburg, Robert C. A. M.

    2015-01-01

    Tyrosyl-DNA phosphodiesterase I (Tdp1) catalyzes the repair of 3′-DNA adducts, such as the 3′-phosphotyrosyl linkage of DNA topoisomerase I to DNA. Tdp1 contains two conserved catalytic histidines: a nucleophilic His (Hisnuc) that attacks DNA adducts to form a covalent 3′-phosphohistidyl intermediate and a general acid/base His (Hisgab), which resolves the Tdp1-DNA linkage. A Hisnuc to Ala mutant protein is reportedly inactive, whereas the autosomal recessive neurodegenerative disease SCAN1 has been attributed to the enhanced stability of the Tdp1-DNA intermediate induced by mutation of Hisgab to Arg. However, here we report that expression of the yeast HisnucAla (H182A) mutant actually induced topoisomerase I-dependent cytotoxicity and further enhanced the cytotoxicity of Tdp1 Hisgab mutants, including H432N and the SCAN1-related H432R. Moreover, the HisnucAla mutant was catalytically active in vitro, albeit at levels 85-fold less than that observed with wild type Tdp1. In contrast, the HisnucPhe mutant was catalytically inactive and suppressed Hisgab mutant-induced toxicity. These data suggest that the activity of another nucleophile when Hisnuc is replaced with residues containing a small side chain (Ala, Asn, and Gln), but not with a bulky side chain. Indeed, genetic, biochemical, and mass spectrometry analyses show that a highly conserved His, immediately N-terminal to Hisnuc, can act as a nucleophile to catalyze the formation of a covalent Tdp1-DNA intermediate. These findings suggest that the flexibility of Tdp1 active site residues may impair the resolution of mutant Tdp1 covalent phosphohistidyl intermediates and provide the rationale for developing chemotherapeutics that stabilize the covalent Tdp1-DNA intermediate. PMID:25609251

  8. Analysis of the active site mechanism of Tyrosyl-DNA phosphodiesterase I: a member of the phospholipase D superfamily

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    Gajewski, Stefan; Comeaux, Evan Q.; Jafari, Nauzanene; Bharatham, Nagakumar; Bashford, Donald; White, Stephen W.; van Waardenburg, Robert C.A.M.

    2011-01-01

    Tyrosyl DNA phosphodiesterase I (Tdp1) is a member of the phospholipase D superfamily and hydrolyzes 3′phospho-DNA adducts via two conserved catalytic histidines, one acting as the lead nucleophile and the second as a general acid/base. Substitution of the second histidine specifically to arginine contributes to the neurodegenerative disease SCAN1. We investigated the catalytic role of this histidine in the yeast protein (His432) using a combination of X-ray crystallography, biochemistry, yeast genetics and theoretical chemistry. The structures of wild type Tdp1 and His432Arg both show a phosphorylated form of the nucleophilic histidine that is not observed in the structure of His432Asn. The phosphohistidine is stabilized in the His432Arg structure by the guanidinium group that also restricts access of a nucleophilic water molecule to the Tdp1-DNA intermediate. Biochemical analyses confirm that His432Arg forms an observable and unique Tdp1-DNA adduct during catalysis. Substitution of His432 by Lys does not affect catalytic activity or yeast phenotype, but substitution with Asn, Gln, Leu, Ala, Ser and Thr all result in severely compromised enzymes and Top1-camptothecin dependent lethality. Surprisingly, His432Asn did not show a stable covalent Tdp1-DNA intermediate which suggests another catalytic defect. Theoretical calculations revealed that the defect resides in the nucleophilic histidine and that the pKa of this histidine is crucially dependent upon the second histidine and the incoming phosphate of the substrate. This represents a unique example of substrate-activated catalysis that applies to the entire phospholipase D superfamily. PMID:22155078

  9. Drosophila TDP1 Ortholog Important for Longevity and Nervous System Maintenance | Center for Cancer Research

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    As the molecule responsible for encoding a cell’s hereditary information, DNA must maintain its integrity. However, nucleic acids are vulnerable to damage by a number of endogenous and exogenous insults, such as reactive oxygen species or enzymes that react with DNA. Thus, other enzymes are tasked with repairing damaged DNA, including tyrosyl-DNA phosphodiesterase 1 (TDP1),

  10. Real-time detection of TDP1 activity using a fluorophore-quencher coupled DNA-biosensor

    DEFF Research Database (Denmark)

    Jensen, Pia Wrensted; Falconi, Mattia; Kristoffersen, Emil Laust

    2013-01-01

    structure of the biosensor. The specific action of TDP1 removes the quencher, thereby enabling optical detection of the fluorophore. Since the enzymatic action of TDP1 is the only “signal amplification” the increase in fluorescence may easily be followed in real-time and allows quantitative analyses of TDP1......Real-time detection of enzyme activities may present the easiest and most reliable way of obtaining quantitative analyses in biological samples. We present a new DNA-biosensor capable of detecting the activity of the potential anticancer drug target tyrosyl-DNA phosphodiesterase 1 (TDP1) in a very...... simple, high throughput, and real-time format. The biosensor is specific for Tdp1 even in complex biological samples, such as human cell extracts, and may consequently find future use in fundamental studies as well as a cancer predictive tool allowing fast analyses of diagnostic cell samples...

  11. Common TDP1 Polymorphisms in Relation to Survival among Small Cell Lung Cancer Patients: A Multicenter Study from the International Lung Cancer Consortium.

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    Lohavanichbutr, Pawadee; Sakoda, Lori C; Amos, Christopher I; Arnold, Susanne M; Christiani, David C; Davies, Michael P A; Field, John K; Haura, Eric B; Hung, Rayjean J; Kohno, Takashi; Landi, Maria Teresa; Liu, Geoffrey; Liu, Yi; Marcus, Michael W; O'Kane, Grainne M; Schabath, Matthew B; Shiraishi, Kouya; Slone, Stacey A; Tardón, Adonina; Yang, Ping; Yoshida, Kazushi; Zhang, Ruyang; Zong, Xuchen; Goodman, Gary E; Weiss, Noel S; Chen, Chu

    2017-12-15

    Purpose: DNA topoisomerase inhibitors are commonly used for treating small-cell lung cancer (SCLC). Tyrosyl-DNA phosphodiesterase (TDP1) repairs DNA damage caused by this class of drugs and may therefore influence treatment outcome. In this study, we investigated whether common TDP1 single-nucleotide polymorphisms (SNP) are associated with overall survival among SCLC patients. Experimental Design: Two TDP1 SNPs (rs942190 and rs2401863) were analyzed in 890 patients from 10 studies in the International Lung Cancer Consortium (ILCCO). The Kaplan-Meier method and Cox regression analyses were used to evaluate genotype associations with overall mortality at 36 months postdiagnosis, adjusting for age, sex, race, and tumor stage. Results: Patients homozygous for the minor allele (GG) of rs942190 had poorer survival compared with those carrying AA alleles, with a HR of 1.36 [95% confidence interval (CI): 1.08-1.72, P = 0.01), but no association with survival was observed for patients carrying the AG genotype (HR = 1.04, 95% CI, 0.84-1.29, P = 0.72). For rs2401863, patients homozygous for the minor allele (CC) tended to have better survival than patients carrying AA alleles (HR = 0.79; 95% CI, 0.61-1.02, P = 0.07). Results from the Genotype Tissue Expression (GTEx) Project, the Encyclopedia of DNA Elements (ENCODE), and the ePOSSUM web application support the potential function of rs942190. Conclusions: We found the rs942190 GG genotype to be associated with relatively poor survival among SCLC patients. Further investigation is needed to confirm the result and to determine whether this genotype may be a predictive marker for treatment efficacy of DNA topoisomerase inhibitors. Clin Cancer Res; 23(24); 7550-7. ©2017 AACR . ©2017 American Association for Cancer Research.

  12. TDP1 repairs nuclear and mitochondrial DNA damage induced by chain-terminating anticancer and antiviral nucleoside analogs

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    Huang, Shar-yin N.; Murai, Junko; Dalla Rosa, Ilaria; Dexheimer, Thomas S.; Naumova, Alena; Gmeiner, William H.; Pommier, Yves

    2013-01-01

    Chain-terminating nucleoside analogs (CTNAs) that cause stalling or premature termination of DNA replication forks are widely used as anticancer and antiviral drugs. However, it is not well understood how cells repair the DNA damage induced by these drugs. Here, we reveal the importance of tyrosyl–DNA phosphodiesterase 1 (TDP1) in the repair of nuclear and mitochondrial DNA damage induced by CTNAs. On investigating the effects of four CTNAs—acyclovir (ACV), cytarabine (Ara-C), zidovudine (AZT) and zalcitabine (ddC)—we show that TDP1 is capable of removing the covalently linked corresponding CTNAs from DNA 3′-ends. We also show that Tdp1−/− cells are hypersensitive and accumulate more DNA damage when treated with ACV and Ara-C, implicating TDP1 in repairing CTNA-induced DNA damage. As AZT and ddC are known to cause mitochondrial dysfunction, we examined whether TDP1 repairs the mitochondrial DNA damage they induced. We find that AZT and ddC treatment leads to greater depletion of mitochondrial DNA in Tdp1−/− cells. Thus, TDP1 seems to be critical for repairing nuclear and mitochondrial DNA damage caused by CTNAs. PMID:23775789

  13. 76 FR 4921 - Government-Owned Inventions; Availability for Licensing

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    2011-01-27

    ... detection of other (protein, tissue, biochemical, or chemical) microarrays. Applications: DNA microarrays... patients, but it often ultimately fails to cure the disease since cancer cells can become resistant to the... effect of antitumor agents. Tyrosyl-DNA phosphodiesterase 1 (Tdp1) is a DNA repair enzyme involved in the...

  14. ATM deficiency results in accumulation of DNA-topoisomerase I covalent intermediates in neural cells.

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    Meryem Alagoz

    Full Text Available Accumulation of peptide-linked DNA breaks contributes to neurodegeration in humans. This is typified by defects in tyrosyl DNA phosphodiesterase 1 (TDP1 and human hereditary ataxia. TDP1 primarily operates at single-strand breaks (SSBs created by oxidative stress or by collision of transcription machinery with topoisomerase I intermediates (Top1-CCs. Cellular and cell-free studies have shown that Top1 at stalled Top1-CCs is first degraded to a small peptide resulting in Top1-SSBs, which are the primary substrates for TDP1. Here we established an assay to directly compare Top1-SSBs and Top1-CCs. We subsequently employed this assay to reveal an increased steady state level of Top1-CCs in neural cells lacking Atm; the protein mutated in ataxia telangiectasia. Our data suggest that the accumulation of endogenous Top1-CCs in Atm-/- neural cells is primarily due to elevated levels of reactive oxygen species. Biochemical purification of Top1-CCs from neural cell extract and the use of Top1 poisons further confirmed a role for Atm during the formation/resolution of Top1-CCs. Finally, we report that global transcription is reduced in Atm-/- neural cells and fails to recover to normal levels following Top1-mediated DNA damage. Together, these data identify a distinct role for ATM during the formation/resolution of neural Top1-CCs and suggest that their accumulation contributes to the neuropathology of ataxia telangiectasia.

  15. Phosphodiesterases in the rat ovary

    DEFF Research Database (Denmark)

    Petersen, Tonny Studsgaard; Stahlhut, Martin; Andersen, Claus Yding

    2015-01-01

    that augmented cAMP levels stimulate primordial follicle growth. The present study examined the gene expression, enzyme activity and immunolocalization of the different cAMP hydrolysing PDEs families in the rat ovary. Further, the effect of PDE4 inhibition on primordial follicle activation in cultured neonatal......Phosphodiesterases (PDEs) are important regulators of the intracellular cAMP concentration, which is a central second messenger that affects a multitude of intracellular functions. In the ovaries, cAMP exerts diverse functions, including regulation of ovulation and it has been suggested...... rat ovaries was also evaluated. We found varied expression of all eight families in the ovary with Pde7b and Pde8a having the highest expression each accounting for more than 20% of the total PDE mRNA. PDE4 accounted for 15-26% of the total PDE activity. Immunoreactive PDE11A was found in the oocytes...

  16. Phosphodiesterase inhibitors in clinical urology.

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    Ückert, Stefan; Kuczyk, Markus A; Oelke, Matthias

    2013-05-01

    To date, benign diseases of the male and female lower urinary and genital tract, such as erectile dysfunction, bladder overactivity, lower urinary tract symptomatology secondary to benign prostatic hyperplasia and symptoms of female sexual dysfunction (including arousal and orgasmic disorders), can be therapeutically approached by influencing the function of the smooth musculature of the respective tissues. The use of isoenzyme-selective phosphodiesterase (PDE) inhibitors is considered a great opportunity to treat various diseases of the human urogenital tract. PDE inhibitors, in particular the PDE5 (cyclic GMP PDE) inhibitors avanafil, lodenafil, sildenafil, tadalafil, udenafil and vardenafil, are regarded as efficacious, having a fast onset of drug action and an improved effect-to-adverse event ratio, combining a high response rate with the advantage of an on-demand intake. The purpose of this review is to summarize recent as well as potential future indications, namely, erectile dysfunction, Peyronie's disease, overactive bladder, urinary stone disease, lower urinary tract symptomatology secondary to benign prostatic hyperplasia and premature ejaculation, for the use of PDE inhibitors in clinical urology.

  17. Two phosphodiesterases from Ustilago maydis share structural and biochemical properties with non-fungal phosphodiesterases

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    Charu eAgarwal

    2010-11-01

    Full Text Available The dependence of Protein Kinase A (PKA activity on cAMP levels is an important facet of the dimorphic switch between budding and filamentous growth as well as for pathogenicity in some fungi. To better understand these processes in the pathogenic fungus Ustilago maydis, we characterized the structure and biochemical functions of two phosphodiesterase (PDE genes. Phosphodiesterases are enzymes involved in cAMP turnover and thus, contribute to the regulation of the cAMP-PKA signaling pathway. Two predicted homologues of PDEs were identified in the genome of U. maydis and hypothesized to be involved in cAMP turnover, thus regulating activity of the PKA catalytic subunit. Both umpde1 and umpde2 genes contain domains associated with phosphodiesterase activity predicted by InterPro analysis. Biochemical characterization of recombinantly produced UmPde1 (U. maydis Phosphodiesterase I and UmPde2 demonstrated that both enzymes have phosphodiesterase activity in vitro, yet neither was inhibited by the phosphodiesterase inhibitor IBMX. Moreover, UmPde1 is specific for cAMP, while UmPde2 has broader substrate specificity, utilizing cAMP and cGMP as substrates. In addition, UmPde2 was also found to have nucleotide phosphatase activity that was higher with GMP compared to AMP. These results demonstrate that UmPde1 is a bona fide phosphodiesterase, while UmPde2 has more general activity as a cyclic nucleotide phosphodiesterase and/or GMP/AMP phosphatase. Thus, UmPde1 and UmPde2 likely have important roles in cell morphology and development and share some characteristics with a variety of non-fungal phosphodiesterases.

  18. Is zucchini a phosphodiesterase or a ribonuclease?

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    Osamu Nureki

    2014-12-01

    Full Text Available Zucchini (Zuc, a member of the phospholipase D (PLD superfamily, is essential for the primary PIWI-interacting RNA (piRNA biogenesis and the suppression of transposon expression, which are crucial for the genome integrity of germline cells. However, it has been ambiguous whether Zuc acts as a phosphodiesterase to produce phosphatidic acid (PA, the lipid signaling molecule, or as a nuclease. The recent three papers describing the crystal structures and functional analyses of fly and mouse Zuc proteins have elucidated that Zuc is a PLD family single-strand ribonuclease, not a phosphodiesterase, and functions in the maturation of primary piRNAs. This review will discuss in detail how the crystal structures clearly predict the function of Zuc, which is subsequently demonstrated by biochemical analysis to conclude the previous controversial discussion on the real function of Zuc.

  19. Tetomilast: new promise for phosphodiesterase-4 inhibitors?

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    Bickston, Stephen J; Snider, Kenneth R; Kappus, Matthew R

    2012-12-01

    Tetomilast is a novel thiazole phosphodiesterase-4 (PDE-4) inhibitor, which may prove useful in both the treatment of inflammatory bowel disease (IBD) and chronic obstructive pulmonary disease (COPD). Here, the authors review the pharmacology of the drug, and offer critical review of the available data for use of tetomilast in the treatment of IBD. Peer-reviewed publications, including Phase I and II clinical trials, all other formats included. Tetomilast may be beneficial in IBD. Small differences in molecules and in recombinant proteins can translate into substantial differences in clinical effects and toxicity in IBD. This is a reasonable approach when exploring new options like tetomilast.

  20. Phosphodiesterase Type 5 Inhibitors, Sport and Doping.

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    Di Luigi, Luigi; Sansone, Massimiliano; Sansone, Andrea; Ceci, Roberta; Duranti, Guglielmo; Borrione, Paolo; Crescioli, Clara; Sgrò, Paolo; Sabatini, Stefania

    Phosphodiesterase type 5 inhibitors (PDE5i) (e.g., sildenafil, tadalafil, vardenafil, and avanafil) are drugs commonly used to treat erectile dysfunction, pulmonary arterial hypertension, and benign prostatic hyperplasia. PDE5i are not prohibited by the World Anti-Doping Agency (WADA) but are alleged to be frequently misused by healthy athletes to improve sporting performance. In vitro and in vivo studies have reported various effects of PDE5i on cardiovascular, muscular, metabolic, and neuroendocrine systems and the potential, therefore, to enhance performance of healthy athletes during training and competition. This suggests well-controlled research studies to examine the ergogenic effects of PDE5i on performance during activities that simulate real sporting situations are warranted to determine if PDE5i should be included on the prohibited WADA list. In the meantime, there is concern that some otherwise healthy athletes will continue to misuse PDE5i to gain an unfair competitive advantage over their competitors.

  1. Phosphodiesterases in endocrine physiology and disease.

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    Vezzosi, Delphine; Bertherat, Jérôme

    2011-08-01

    The cAMP-protein kinase A pathway plays a central role in the development and physiology of endocrine tissues. cAMP mediates the intracellular effects of numerous peptide hormones. Various cellular and molecular alterations of the cAMP-signaling pathway have been observed in endocrine diseases. Phosphodiesterases (PDEs) are key regulatory enzymes of intracellular cAMP levels. Indeed, PDEs are the only known mechanism for inactivation of cAMP by catalysis to 5'-AMP. It has been suggested that disruption of PDEs could also have a role in the pathogenesis of many endocrine diseases. This review summarizes the most recent advances concerning the role of the PDEs in the physiopathology of endocrine diseases. The potential significance of this knowledge can be easily envisaged by the development of drugs targeting specific PDEs.

  2. Effectiveness of Phosphodiesterase-5 Inhibitor Therapy for Portopulmonary Hypertension

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    Jolene H Fisher

    2015-01-01

    Full Text Available BACKGROUND: Portopulmonary hypertension is associated with significant morbidity and mortality. Phosphodiesterase-5 inhibitor therapy is efficacious in other causes of WHO group I pulmonary arterial hypertension.

  3. Assay of cyclic nucleotide phosphodiesterase using radiolabeled and fluorescent substrates

    International Nuclear Information System (INIS)

    Kincaid, R.L.; Manganiello, V.C.

    1988-01-01

    There are four major classes of phosphodiesterase with different specificities for cAMP and cGMP and different allosteric regulators. Type I phosphodiesterase is activated by calmodulin plus Ca/sup 2+/ and has a higher affinity for cGMP than cAMP. Type II phosphodiesterase likewise has a higher affinity for cGMP than cAMP, but the activity toward one substrate is markedly stimulated by low (micromolar) concentrations of the other nucleotide. Type III phosphodiesterase has a higher affinity for cAMP than cGMP; its activity is increased in responsive cells by certain hormones, e.g., insulin, isoproterenol. Type IV phosphodiesterase is the cGMP-specific enzyme, which also has an allosteric binding site for cGMP. An example of this class of enzyme is the one from retinal rod outer segments, which is activated by light via rhodopsin and the guanine nucleotide-binding protein transducin. There appears to be little structural relatedness among these enzymes based on immunologic analysis, consistent with the possibility that divergent forms evolved from an ancestral enzyme. Determination of the amount of a specific form of phosphodiesterase in crude material is often difficult. Modification of assay conditions by judicious choice of substrate and/or inhibitor concentrations may selectively favor (or reduce) the activity of a particular form; in many instances, however, some fractionation of enzymes may be necessary. This is discussed more fully in the final section of this chapter

  4. Cyclic nucleotide specific phosphodiesterases of Leishmania major

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    Linder Markus

    2006-03-01

    Full Text Available Abstract Background Leishmania represent a complex of important human pathogens that belong to the systematic order of the kinetoplastida. They are transmitted between their human and mammalian hosts by different bloodsucking sandfly vectors. In their hosts, the Leishmania undergo several differentiation steps, and their coordination and optimization crucially depend on numerous interactions between the parasites and the physiological environment presented by the fly and human hosts. Little is still known about the signalling networks involved in these functions. In an attempt to better understand the role of cyclic nucleotide signalling in Leishmania differentiation and host-parasite interaction, we here present an initial study on the cyclic nucleotide-specific phosphodiesterases of Leishmania major. Results This paper presents the identification of three class I cyclic-nucleotide-specific phosphodiesterases (PDEs from L. major, PDEs whose catalytic domains exhibit considerable sequence conservation with, among other, all eleven human PDE families. In contrast to other protozoa such as Dictyostelium, or fungi such as Saccharomyces cerevisiae, Candida ssp or Neurospora, no genes for class II PDEs were found in the Leishmania genomes. LmjPDEA contains a class I catalytic domain at the C-terminus of the polypeptide, with no other discernible functional domains elsewhere. LmjPDEB1 and LmjPDEB2 are coded for by closely related, tandemly linked genes on chromosome 15. Both PDEs contain two GAF domains in their N-terminal region, and their almost identical catalytic domains are located at the C-terminus of the polypeptide. LmjPDEA, LmjPDEB1 and LmjPDEB2 were further characterized by functional complementation in a PDE-deficient S. cerevisiae strain. All three enzymes conferred complementation, demonstrating that all three can hydrolyze cAMP. Recombinant LmjPDEB1 and LmjPDEB2 were shown to be cAMP-specific, with Km values in the low micromolar range

  5. Interactions of chlorphenesin and divalent metal ions with phosphodiesterase.

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    Edelson, J; McMullen, J P

    1976-09-01

    Chlorphenesin inhibition of the hydrolysis of cyclic AMP by guinea-pig lung phosphodiesterase was reversed by the addition of exogenous magnesium ions. Chlorphenesin and theophylline inhibition of this enzyme was shown to be noncompetitive when the substrate concentration was low. Kinetic studies of the inhibition of beef heart phosphodiesterase by chlorphenesin and theophylline indicated that the substrate concentration was a factor in determining whether inhibition was competitive or noncompetitive. Calcium, cobalt and copper ions were inhibitory to guinea-pig lung phosphodiesterase. The inhibition due to chlorphenesin was partially reversed by low (40 mM or less) concentrations of barium ions; high concentrations of barium ions, or manganese ions, were inhibitory. The concentration of the divalent cation did not affect the type of inhibition that was observed.

  6. Effects of fenspiride on human bronchial cyclic nucleotide phosphodiesterase isoenzymes: functional and biochemical study.

    Science.gov (United States)

    Cortijo, J; Naline, E; Ortiz, J L; Berto, L; Girard, V; Malbezin, M; Advenier, C; Morcillo, E J

    1998-01-02

    We have investigated the role of human bronchial cyclic nucleotide phosphodiesterases in the effects of fenspiride, a drug endowed with bronchodilator and anti-inflammatory properties. Functional studies on human isolated bronchi showed that fenspiride (10(-6)-3 x 10(-3) M, 30 min) induced a shift to the left of the concentration-response curves for isoprenaline and sodium nitroprusside with -logEC50 values of 4.1+/-0.1 (n = 7) and 3.5+/-0.2 (n = 8), respectively. Biochemical studies were carried out on three human bronchi in which separation of cyclic nucleotide phosphodiesterase isoenzymes was performed by ion exchange chromatography followed by determination of phosphodiesterase activity with a radioisotopic method. Phosphodiesterase 4 (cyclic AMP-specific) and phosphodiesterase 5 (cyclic GMP-specific) were the major phosphodiesterase isoforms present in the human bronchial tissue. The presence of phosphodiesterase 1 (Ca2+/calmodulin-stimulated), phosphodiesterase 2 (cyclic GMP-stimulated) and, in two cases, phosphodiesterase 3 (cyclic GMP-inhibited) was also identified. Fenspiride inhibited phosphodiesterase 4 and phosphodiesterase 3 activities with -logIC50 values of 4.16+/-0.09 and 3.44+/-0.12, respectively. Phosphodiesterase 5 activity was also inhibited with a -logIC50 value of approximately 3.8. Fenspiride (fenspiride is an effective inhibitor of both cyclic AMP and cyclic GMP hydrolytic activity in human bronchial tissues and this action may contribute to its airway effects.

  7. Effect of phosphodiesterase inhibitors on human arteries in vitro

    NARCIS (Netherlands)

    Vroom, M. B.; Pfaffendorf, M.; van Wezel, H. B.; van Zwieten, P. A.

    1996-01-01

    In the present study, we investigated if the relaxant effects of phosphodiesterase (PDE) III inhibitors on human vessels could be inhibited by a nitric oxide synthase blocker, L-NAME, or by a blocker of ATP-sensitive potassium channels (KATP), glibenclamide. The experiments were performed using an

  8. Invitro pharmacology of r-80122, a novel phosphodiesterase inhibitor

    NARCIS (Netherlands)

    WILHELM, D; WILFFERT, B; JANSSENS, WJ; LEIDIG, A; MEUTER, C; EBBERT, M; Peters, Thies

    1992-01-01

    The cardiac in vitro effects of R 80122, a novel phosphodiesterase (PDE) inhibitor, were investigated and compared with those of the reference compound milrinone and of the calcium-sensitizer adibendan. In guinea pig left atria, both milrinone and R 80122 increased contractile force; 10 muM

  9. Phosphodiesterase 5 inhibition as a therapeutic target for ischemic stroke

    DEFF Research Database (Denmark)

    Ölmestig, Joakim N E; Marlet, Ida R; Hainsworth, Atticus H

    2017-01-01

    Phosphodiesterase 5 inhibitors (PDE5i), such as sildenafil (Viagra®) are widely used for erectile dysfunction and pulmonary hypertension. Preclinical studies suggest that PDE5i may improve functional outcome following ischemic stroke. In this systematic review we aimed to evaluate the effects...

  10. Upregulation of Phosphodiesterase type 5 in the Hyperplastic Prostate

    NARCIS (Netherlands)

    W. Zhang (Wenhao); N. Zang (Ning); Y. Jiang (Yaoming); P. Chen (Ping); X. Wang (Xinghuan); X. Zhang (Xinhua)

    2015-01-01

    textabstractBoth erectile dysfunction (ED) and lower urinary tract symptoms (LUTS)/benign prostatic hyperplasia (BPH) are common in the aging male. Numerous clinical trials have demonstrated the efficacy and safety of phosphodiesterase type 5 inhibitors (PDE5-Is) for treating LUTS/BPH with/without

  11. In vitro pharmacology of R 80122, a novel phosphodiesterase inhibitor

    NARCIS (Netherlands)

    Wilhelm, D.; Wilffert, B.; Janssens, W.J.; Leidig, A.; Meuter, C.; Ebbert, M.; Peters, Thies

    1992-01-01

    The cardiac in vitro effects of R 80122, a novel phosphodiesterase (PDE) inhibitor, were investigated and compared with those of the reference compound milrinone and of the calcium-sensitizer adibendan. In guinea pig left atria, both milrinone and R 80122 increased contractile force; 10 μM milrinone

  12. CHARACTERIZATION OF ORG-20241, A COMBINED PHOSPHODIESTERASE IV/III CYCLIC-NUCLEOTIDE PHOSPHODIESTERASE INHIBITOR FOR ASTHMA

    NARCIS (Netherlands)

    NICHOLSON, CD; BRUIN, J; BARRON, E; SPIERS, [No Value; DEBOER, J; VANAMSTERDAM, RGM; ZAAGSMA, J; KELLY, JJ; DENT, G; GIEMBYCZ, MA; BARNES, PJ

    The pharmacological profile of a novel cyclic nucleotide phosphodiesterase (PDE) inhibitor, Org 20241, has been characterized. The compound selectively inhibits PDE IV (plC(50), 5.2-6.1) and PDE III (plC(50), 4.4-4.6) from animal and human tissues. Org 20241 relaxed preparations of bovine trachea

  13. Selective phosphodiesterase inhibitors: a promising target for cognition enhancement

    OpenAIRE

    Reneerkens, Olga A. H.; Rutten, Kris; Steinbusch, Harry W. M.; Blokland, Arjan; Prickaerts, Jos

    2008-01-01

    Rationale One of the major complaints most people face during aging is an impairment in cognitive functioning. This has a negative impact on the quality of daily life and is even more prominent in patients suffering from neurodegenerative and psychiatric disorders including Alzheimer?s disease, schizophrenia, and depression. So far, the majority of cognition enhancers are generally targeting one particular neurotransmitter system. However, recently phosphodiesterases (PDEs) have gained increa...

  14. Partial reconstitution of photoreceptor cGMP phosphodiesterase characteristics in cGMP phosphodiesterase-5.

    Science.gov (United States)

    Granovsky, A E; Artemyev, N O

    2001-06-15

    Photoreceptor cGMP phosphodiesterases (PDE6) are uniquely qualified to serve as effector enzymes in the vertebrate visual transduction cascade. In the dark-adapted photoreceptors, the activity of PDE6 is blocked via tight association with the inhibitory gamma-subunits (Pgamma). The Pgamma block is removed in the light-activated PDE6 by the visual G protein, transducin. Transducin-activated PDE6 exhibits an exceptionally high catalytic rate of cGMP hydrolysis ensuring high signal amplification. To identify the structural determinants for the inhibitory interaction with Pgamma and the remarkable cGMP hydrolytic ability, we sought to reproduce the PDE6 characteristics by mutagenesis of PDE5, a related cyclic GMP-specific, cGMP-binding PDE. PDE5 is insensitive to Pgamma and has a more than 100-fold lower k(cat) for cGMP hydrolysis. Our mutational analysis of chimeric PDE5/PDE6alpha' enzymes revealed that the inhibitory interaction of cone PDE6 catalytic subunits (PDE6alpha') with Pgamma is mediated primarily by three hydrophobic residues at the entry to the catalytic pocket, Met(758), Phe(777), and Phe(781). The maximal catalytic rate of PDE5 was enhanced by at least 10-fold with substitutions of PDE6alpha'-specific glycine residues for the corresponding PDE5 alanine residues, Ala(608) and Ala(612). The Gly residues are adjacent to the highly conserved metal binding motif His-Asn-X-X-His, which is essential for cGMP hydrolysis. Our results suggest that the unique Gly residues allow the PDE6 metal binding site to adopt a more favorable conformation for cGMP hydrolysis.

  15. Phosphodiesterase isoenzyme families in human osteoarthritis chondrocytes – functional importance of phosphodiesterase 4

    Science.gov (United States)

    Tenor, Hermann; Hedbom, Erik; Häuselmann, Hans-Jörg; Schudt, Christian; Hatzelmann, Armin

    2002-01-01

    We studied whether selective inhibitors of cyclic nucleotide hydrolysing phosphodiesterase (PDE) isoenzymes influence IL-1β-induced nitric oxide (NO) release from human articular chondrocytes. In addition, the pattern of PDE isoenzymes contributing to cyclic nucleotide hydrolysis in human chondrocytes was characterized.Chondrocytes were isolated from human osteoarthritic cartilage and cultured in alginate beads. IL-1β-induced chondrocyte products (nitric oxide and prostaglandin E2) were measured in culture supernatants after 48 h incubation time. PDE activities were assessed in chondrocyte lysates. Inducible nitric oxide synthase (iNOS) and PDE4A-D proteins were detected by immunoblotting.The selective PDE4 inhibitors Piclamilast and Roflumilast partially attenuated IL-1β-induced NO production whereas selective inhibitors of PDE2 (EHNA), PDE3 (Motapizone) or PDE5 (Sildenafil) were inactive. Indomethacin reversed the reduction of IL-1β-induced NO by PDE4 inhibitors. It was shown that autocrine prostaglandin E2 (PGE2) enabled PDE4 inhibitors to reduce IL-1β-induced NO in this experimental setting.Major PDE4 and PDE1 activities were identified in chondrocyte lysates whereas only minor activities of PDE2, 3 and 5 were found. IL-1β and cyclic AMP-mimetics upregulated PDE4 activity and this was associated with an augmentation of PDE4B2 protein.Based on the view that nitric oxide contributes to cartilage degradation in osteoarthritis our study suggests that PDE4 inhibitors may have chondroprotective effects. PMID:11834608

  16. Analysis of the effects of phosphodiesterase type 3 and 4 inhibitors in cerebral arteries

    DEFF Research Database (Denmark)

    Birk, Steffen; Edvinsson, Lars; Olesen, Jes

    2004-01-01

    Inhibitors of phosphodiesterases 3 and 4, the main cyclic AMP (cAMP) degrading enzymes in arteries, may have therapeutic potential in cerebrovascular disorders. We analysed the effects of such phosphodiesterases in guinea pig cerebral arteries with organ bath technique and cyclic nucleotide assays...... the major contributors to total cAMP hydrolysis in the arteries examined. The phosphodiesterase 3 inhibitors additionally attenuated cyclic GMP (cGMP) hydrolysis, but relaxant responses were not dependent on an intact endothelium or on the nitric oxide-cGMP pathway. Conversely, the phosphodiesterase 4...

  17. Radioimmunoassays for cyclic AMP cross-react with phosphodiesterase inhibitors and buffer components

    NARCIS (Netherlands)

    Sinha, B; Semmler, J; Haen, E; Moeller, J; Endres, S

    We addressed the issue of cross-reactivity of several commonly used phosphodiesterase inhibitors with radioimmunoassays for cyclic AMP, after we had observed a considerably high cross-reactivity with a noncommercial antibody. Theophylline, pentoxifylline, penthydroxifylline (BL 194), albifylline

  18. Phosphodiesterase III inhibition affects platelet-monocyte aggregate formation depending on the axis of stimulation.

    NARCIS (Netherlands)

    Horn, N.A.; Anastase, D.M.; Hecker, K.E.; Baumert, J.H.; Scheffer, G.J.; Rossaint, R.

    2006-01-01

    OBJECTIVE: The purpose of this study was to investigate the effect of the phosphodiesterase (PDE) type 3 inhibitor milrinone on the adhesion of platelets to monocytes in vitro. DESIGN: Prospective study. SETTING: University experimental laboratory. PARTICIPANTS: Ten healthy volunteers.

  19. Oral phosphodiesterase type 5 inhibitors alleviate recurrent priapism complicating thalassemia intermedia: a case report

    NARCIS (Netherlands)

    Tzortzis, Vassilios; Mitrakas, Lampros; Gravas, Stavros; Mamoulakis, Charalampos; Meissner, Andreas; Kyriakou, Despina; Melekos, Michael D.

    2009-01-01

    Recurrent ischemic priapism still remains a serious and difficult to treat complication of certain hematological disorders. Elucidation of the underlying pathophysiologic mechanisms and application of new effective prophylactic treatments are needed. To present the efficacy of phosphodiesterase type

  20. Evidence for a Messenger Function of Cyclic GMP During Phosphodiesterase Induction in Dictyostelium discoideum

    NARCIS (Netherlands)

    Haastert, Peter J.M. van; Pasveer, Frank J.; Meer, Rob C. van der; Heijden, Paul R. van der; Walsum, Hans van; Konijn, Theo M.

    1982-01-01

    Chemotactic stimulation of vegetative or aggregative Dictyostelium discoideum cells induced a transient elevation of cyclic GMP levels. The addition of chemoattractants to postvegetative cells by pulsing induced phosphodiesterase activity. The following lines of evidence suggest a messenger function

  1. The role of cGMP hydrolysing phosphodiesterases 1 and 5 in cerebral artery dilatation

    DEFF Research Database (Denmark)

    Kruuse, Christina; Rybalkin, S D; Khurana, T S

    2001-01-01

    The aim was to investigate the presence and activity of cGMP hydrolysing phosphodiesterases in guinea pig basilar arteries and the effect of selective and non-selective phosphodiesterase inhibitors on cerebral artery dilatation involving the nitric oxide (NO)-guanosine cyclic 3'5-monophosphate (cGMP...... a close relation to the nitric oxide-cGMP pathway. The responses to zaprinast and dipyridamole, however, were not only moderately affected, but also restored by sodium nitroprusside (0.1 microM) pretreatment. At high concentrations, the dilatory effects of zaprinast and dipyridamole were partly caused...... by cGMP-independent mechanisms. Targeting the phosphodiesterases present in cerebral arteries, with selective inhibitors or activators of phosphodiesterase, may be a possible new way of treating cerebrovascular disease....

  2. The effect of phosphodiesterase-5 inhibitors on cerebral blood flow in humans

    DEFF Research Database (Denmark)

    Pauls, Mathilde Mh; Moynihan, Barry; Barrick, Thomas R

    2018-01-01

    , ED, type 2 diabetes, stroke, pulmonary hypertension, Becker muscular dystrophy and subarachnoid haemorrhage. Most studies used middle cerebral artery flow velocity to estimate CBF. Few studies employed direct measurements of tissue perfusion. Resting CBF velocity was unaffected by phosphodiesterase-5...... inhibitors, but cerebrovascular regulation was improved in ED, pulmonary hypertension, diabetes, Becker's and a group of healthy volunteers. This evidence suggests that phosphodiesterase-5 inhibitors improve responsiveness of the cerebral vasculature, particularly in disease states associated...

  3. Phosphodiesterase Inhibition to Target the Synaptic Dysfunction in Alzheimer's Disease

    Science.gov (United States)

    Bales, Kelly R.; Plath, Niels; Svenstrup, Niels; Menniti, Frank S.

    Alzheimer's Disease (AD) is a disease of synaptic dysfunction that ultimately proceeds to neuronal death. There is a wealth of evidence that indicates the final common mediator of this neurotoxic process is the formation and actions on synaptotoxic b-amyloid (Aβ). The premise in this review is that synaptic dysfunction may also be an initiating factor in for AD and promote synaptotoxic Aβ formation. This latter hypothesis is consistent with the fact that the most common risk factors for AD, apolipoprotein E (ApoE) allele status, age, education, and fitness, encompass suboptimal synaptic function. Thus, the synaptic dysfunction in AD may be both cause and effect, and remediating synaptic dysfunction in AD may have acute effects on the symptoms present at the initiation of therapy and also slow disease progression. The cyclic nucleotide (cAMP and cGMP) signaling systems are intimately involved in the regulation of synaptic homeostasis. The phosphodiesterases (PDEs) are a superfamily of enzymes that critically regulate spatial and temporal aspects of cyclic nucleotide signaling through metabolic inactivation of cAMP and cGMP. Thus, targeting the PDEs to promote improved synaptic function, or 'synaptic resilience', may be an effective and facile approach to new symptomatic and disease modifying therapies for AD. There continues to be a significant drug discovery effort aimed at discovering PDE inhibitors to treat a variety of neuropsychiatric disorders. Here we review the current status of those efforts as they relate to potential new therapies for AD.

  4. Radioprotection of mouse intestine by inhibitors of cyclic amp phosphodiesterase

    International Nuclear Information System (INIS)

    Lehnert, S.

    1979-01-01

    The survival of colony-forming units of the jejunal crypt was used to assay the radioprotective capacity of various inhibitors of cyclic AMP phosphodiesterase. DL-152, RO-20-1724 and the methyl xanthines, caffeine, theophylline, and methyl isbutyl xanthine (MIX) were all found to have some radioprotective effect. The degree of radioprotecton depended on the route of administration of the drug and on the timing of administration with respect to irradiation. Optimum survival of crypt stem cells was found following intraperitoneal administration of DL-152 (60 min before irradiation) or MIX (30 min before irradiaton), and following intravenous administration of caffeine (60 to 120 min before irradiaton) or theophylline (60 min before irradiation). When these protocols were used, crypt stem cell survival could be enhanced by a factor of from 6 to 7. All the compounds investigated produced some elevation of cyclic AMP content of the whole jejunum; this was found to be simultaneous with or to precede the period of maximum radioprotection. Cyclic AMP was localized with immunofluorescent staining; following injection of DL-152 it was found to be elevated in all parts of the jejunum but to the greatest extent in the lower part of the crypt. Survival curves for crypt stem cells from MIX and DL-152 treated mice were found to have almost the same exponential slope as the saline-injected control, suggesting that the mechanism of protection does not depend on induction of hypoxia

  5. New Therapeutic Applications of Phosphodiesterase 5 Inhibitors (PDE5-Is).

    Science.gov (United States)

    Ribaudo, Giovanni; Pagano, Mario Angelo; Bova, Sergio; Zagotto, Giuseppe

    2016-01-01

    Phosphodiesterase 5 inhibitors (PDE5-Is) sildenafil, vardenafil, tadalafil and the recently approved avanafil represent the first-line choice for both on-demand and chronic treatment of erectile dysfunction (ED). In addition to this, sildenafil and tadalafil, have also been approved for the treatment of pulmonary arterial hypertension. Due to its expression and localization in many tissues, PDE5 and its regulation has been reported to be involved in several other diseases. We aim to provide an updated overview of the emerging therapeutic applications of PDE5-Is besides ED, taking into account the latest ongoing research reports. We searched online databases (Pubmed, Reaxys, Scopus) to lay the bases for an accurate, quality criteria-based literature update. We focused our attention on most recent research reports, in particular when supported by pre-clinical and clinical data. The regulation of PDE5 may influence pathological conditions such as, among the others, heart failure, cystic fibrosis, cancer, CNS-related diseases, diabetes and dysfunctions affecting male urinary/reproductive system. Sildenafil, vardenafil, tadalafil and the other chemical entities considered PDE5-Is showed overall positive results and significant improvements in the studied disease, thus some discordant results, in particular when comparing pre-clinical and clinical data, have to be pointed out, suggesting that further insights are needed especially to assess the exact molecular pathway underlying.

  6. Phosphodiesterases regulate airway smooth muscle function in health and disease.

    Science.gov (United States)

    Krymskaya, Vera P; Panettieri, Reynold A

    2007-01-01

    On the basis of structure, regulation, and kinetic properties, phosphodiesterases (PDEs) represent a superfamily of enzymes divided into 11 subfamilies that catalyze cytosolic levels of 3',5'-cyclic adenosine monophosphate (cAMP) or 3',5'-cyclic guanosine monophosphate (cGMP) to 5'-AMP or 5'-GMP, respectively. PDE4 represents the major PDE expressed in inflammatory cells as well as airway smooth muscle (ASM), and selective PDE4 inhibitors provide a broad spectrum of anti-inflammatory effects such as abrogating cytokine and chemokine release from inflammatory cells and inhibiting inflammatory cell trafficking. Due to cell- and tissue-specific gene expression and regulation, PDEs modulate unique organ-based functions. New tools or compounds that selectively inhibit PDE subfamilies and genetically engineered mice deficient in selective isoforms have greatly enhanced our understanding of PDE function in airway inflammation and resident cell function. This chapter will focus on recent advances in our understanding of the role of PDE in regulating ASM function.

  7. The safety of phosphodiesterase type 5 inhibitors for erectile dysfunction.

    Science.gov (United States)

    Ventimiglia, Eugenio; Capogrosso, Paolo; Montorsi, Francesco; Salonia, Andrea

    2016-01-01

    Phosphodiesterase type 5 inhibitors (PDE5Is) are the leading drugs for the treatment of erectile dysfunction (ED), being recommended as a first line treatment by both the European and US urological guidelines. PDE5Is are highly effective as compared to placebo, well tolerated and have a very low, though not negligible, rate of severe treatment-related adverse events. This paper reviews the safety profile of currently available PDE5Is, comparing them in a broad spectrum ED population and outlining a number of real-life aspects of importance in the real-life everyday clinical setting. Guidelines unanimously agree in considering PDE5Is as first line treatments for ED when well-tolerated and not contraindicated. Despite the fact that no high-grade evidence comparing the efficacy and the safety for PDE5Is is currently available, published data seem to suggest that there are no major differences in their safety profiles. Moreover, although oral PDE5Is were shown to cause more AEs than placebo, they were generally mild and well tolerated.

  8. Phosphodiesterase type 5 inhibitor abuse: a critical review.

    Science.gov (United States)

    Lowe, Gregory; Costabile, Raymond

    2011-06-01

    Abuse of sildenafil has been reported since its introduction in 1999 and commonly documented in combination with illicit drugs among men and women of all ages. Increased risks of sexually transmissible diseases including HIV have been associated with sildenafil use in men who have sex with men. Recognizing the abuse potential of phosphodiesterase type 5 inhibitors (PDE5), we aim to summarize the current knowledge of this abuse. An investigation of EMBASE, PubMed, the Food and Drug Administration (FDA) website, MedWatch, and search engines was performed to evaluate information regarding sildenafil, tadalafil, and vardenafil abuse. The EMBASE search provided 46 articles fitting the search criteria and evaluation led to 21 separate publications with specific information regarding PDE5 abuse. A PubMed search found 10 additional publications. MedWatch reported 44 separate warnings since 2000, most of which reported contamination of herbal products with active drug components. Few reports of abuse were among the 14,818 reports in the FDA AERS for sildenafil. A search for "internet drug store" revealed 6.4 million hits and of 7000 internet pharmacies identified by the Verified Internet Pharmacy Practice Sites Program (VIPPS) only 4% were in proper compliance. The role internet pharmacies play in counterfeit PDE5 or abuse is not well documented; however based on easy access, direct patient marketing, and low advertised cost it is likely this role is underreported. Currently the best recommendation for providers is to recognize the possibility of abuse and to educate patients on risks of this behavior.

  9. Phosphodiesterase 5 inhibitors in the treatment of premature ejaculation.

    Science.gov (United States)

    Wang, W F; Minhas, S; Ralph, D J

    2006-10-01

    To date, there is no FDA-approved therapy for premature ejaculation (PE). Recently, phosphodiesterase 5 inhibitors (PDE5-Is) have been demonstrated to have encouraging results in the treatment of PE by a few studies. The aim of this review was to assess the updated manuscripts and thereafter present the practical recommendations and possible mechanisms concerning PDE5-Is for treating PE. Using MEDLINE, we searched and assessed the peer manuscripts published from 1 January 1996 to 1 September 2005 about PDE5-Is for treating PE. The results show that the number of patients in all the reports is very few and most of the studies do not employ double-blinded and placebo-controlled tests, though they are prospective and randomized. Therefore, the results and conclusions might be biased. PDE5-Is are suggested to be used in PE with old age or associated with erectile dysfunction (ED), or to be employed alone or in combination with selective-serotonin reuptake inhibitors (SSRIs) when SSRIs fail to treat PE; behavioural therapy is proposed to be used for preventing the recurrence of PE following withdrawal of PDE5-Is. In addition, for the PE patient with a definite aetiological cause, the aetiology should be cured first, if PE still exists, followed by PDE-Is prescription. Possible mechanisms that are involved include relaxing the smooth muscles of vas deferens, seminal vesicle, prostate and urethra; decreasing the central sympathetic output; inducing peripheral analgesia; prolonging the duration of erection; and increasing confidence, the perception of ejaculatory control, overall sexual satisfaction, and decreasing the post-orgasmic refractory time to achieve a second erection after ejaculation. Well-designed multicentre studies are urgently warranted to further elucidate the efficacies and safety as well as mechanisms of PDE5-Is in the treatment of PE.

  10. Structure and Mechanism of PhnP, a Phosphodiesterase of the Carbon-Phosphorus Lyase Pathway

    DEFF Research Database (Denmark)

    He, Shu-Mei; Wathier, Matthew; Podzelinska, Kateryna

    2011-01-01

    PhnP is a phosphodiesterase that plays an important role within the bacterial carbon-phosphorus lyase (CP-lyase) pathway by recycling a "dead-end" intermediate, 5-phospho-α-d-ribosyl 1,2-cyclic phosphate, that is formed during organophosphonate catabolism. As a member of the metallo-β-lactamase s......PhnP is a phosphodiesterase that plays an important role within the bacterial carbon-phosphorus lyase (CP-lyase) pathway by recycling a "dead-end" intermediate, 5-phospho-α-d-ribosyl 1,2-cyclic phosphate, that is formed during organophosphonate catabolism. As a member of the metallo...

  11. A selective phosphodiesterase 10A inhibitor reduces l-dopa-induced dyskinesias in parkinsonian monkeys.

    Science.gov (United States)

    Beck, Goichi; Maehara, Shunsuke; Chang, Phat Ly; Papa, Stella M

    2018-03-06

    Phosphodiesterase 10A is a member of the phosphodiesterase family whose brain expression is restricted to the striatum. Phosphodiesterase 10A regulates cyclic adenosine monophosphate and cyclic guanosine monophosphate, which mediate responses to dopamine receptor activation, and the levels of these cyclic nucleotides are decreased in experimental models of l-dopa-induced dyskinesia. The elevation of cyclic adenosine monophosphate/cyclic guanosine monophosphate levels by phosphodiesterase 10A inhibition may thus be targeted to reduce l-dopa-induced dyskinesia. The present study was aimed at determining the potential antidyskinetic effects of phosphodiesterase 10A inhibitors in a primate model of Parkinson's disease (PD). The experiments performed in this model were also intended to provide translational data for the design of future clinical trials. Five MPTP-treated macaques with advanced parkinsonism and reproducible l-dopa-induced dyskinesia were used. MR1916, a selective phosphodiesterase 10A inhibitor, at doses 0.0015 to 0.05 mg/kg, subcutaneously, or its vehicle (control test) was coadministered with l-dopa methyl ester acutely (predetermined optimal and suboptimal subcutaneous doses) and oral l-dopa chronically as daily treatment for 5 weeks. Standardized scales were used to assess motor disability and l-dopa-induced dyskinesia by blinded examiners. Pharmacokinetics was also examined. MR1916 consistently reduced l-dopa-induced dyskinesia in acute tests of l-dopa optimal and suboptimal doses. Significant effects were present with every MR1916 dose tested, but the most effective was 0.015 mg/kg. None of the MR1916 doses tested affected the antiparkinsonian action of l-dopa at the optimal dose. The anti-l-dopa-induced dyskinesia effect of MR1916 (0.015 mg/kg, subcutaneously) was sustained with chronic administration, indicating that tolerance did not develop over the 5-week treatment. No adverse effects were observed after MR1916 administration acutely or

  12. Carbon-14 labelled nitrogen heterocycles; the syntheses of three phosphodiesterase inhibitors

    International Nuclear Information System (INIS)

    Lawrie, K.W.M.; Novelli, C.E.A.; Saunders, David

    1995-01-01

    The syntheses of three heterocyclic phosphodiesterase inhibitors are described from a common radiolabelled precursor, namely 2-propoxybenzo[cyano- 14 C] nitrile. Conversion of the nitrile to the corresponding methyl ketone or amidine allows elaboration of the heterocycles radiolabelled within the ring systems. (Author)

  13. 6-Nitrobenzimidazole derivatives: potential phosphodiesterase inhibitors: synthesis and structure-activity relationship.

    Science.gov (United States)

    Khan, K M; Shah, Zarbad; Ahmad, V U; Ambreen, N; Khan, M; Taha, M; Rahim, F; Noreen, S; Perveen, S; Choudhary, M I; Voelter, W

    2012-02-15

    6-Nitrobenzimidazole derivatives (1-30) synthesized and their phosphodiesterase inhibitory activities determined. Out of thirty tested compounds, ten showed a varying degrees of phosphodiesterase inhibition with IC(50) values between 1.5±0.043 and 294.0±16.7 μM. Compounds 30 (IC(50)=1.5±0.043 μM), 1 (IC(50)=2.4±0.049 μM), 11 (IC(50)=5.7±0.113 μM), 13 (IC(50)=6.4±0.148 μM), 14 (IC(50)=10.5±0.51 μM), 9 (IC(50)=11.49±0.08 μM), 3 (IC(50)=63.1±1.48 μM), 10 (IC(50)=120.0±4.47 μM), and 6 (IC(50)=153.2±5.6 μM) showed excellent phosphodiesterase inhibitory activity, much superior to the standard EDTA (IC(50)=274±0.007 μM), and thus are potential molecules for the development of a new class of phosphodiesterase inhibitors. A structure-activity relationship is evaluated. All compounds are characterized by spectroscopic parameters. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Carbon-14 labelled nitrogen heterocycles; the syntheses of three phosphodiesterase inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Lawrie, K.W.M.; Novelli, C.E.A.; Saunders, David [SmithKline Beecham Pharmaceuticals Research and Development, Harlow (United Kingdom). Synthetic Isotope Chemistry Dept.; Coates, W.J. [SmithKline Beecham Pharmaceuticals Research and Development, Welwyn (United Kingdom)

    1995-09-01

    The syntheses of three heterocyclic phosphodiesterase inhibitors are described from a common radiolabelled precursor, namely 2-propoxybenzo[cyano-{sup 14}C] nitrile. Conversion of the nitrile to the corresponding methyl ketone or amidine allows elaboration of the heterocycles radiolabelled within the ring systems. (Author).

  15. Transient Kinetics of a cGMP-dependent cGMP-specific Phosphodiesterase from Dictyostelium discoideum

    NARCIS (Netherlands)

    Haastert, Peter J.M. van; Lookeren Campagne, Michiel M. van

    1984-01-01

    Chemotactic stimulation of Dictyostelium discoideum cells induces a fast transient increase of cGMP levels which reach a peak at 10 s. Prestimulation levels are recovered in ~30 s, which is achieved mainly by the action of a guanosine 3',5'-monophosphate cGMP-specific phosphodiesterase. This enzyme

  16. Characterization and Targeting of the Aldehyde Dehydrogenase Subpopulation in Ovarian Cancer

    Science.gov (United States)

    2013-07-01

    interactions R01 Role: Co-I (van Waardenburg ) Sponsor: NIH/NCI The DNA repair enzyme tyrosyl-DNA phosphodiesterase I as therapeutic target Major...ports the hypothesis that incessant ovulation is the culprit for tumor initi- ation. For example, women with poly- cystic ovarian syndrome , who by...nulliparous women, women with poly- cystic ovary syndrome , and women with other types of primary infertility who also have increased gonadotropin pro

  17. Effects of phosphodiesterase III inhibition on length-dependent regulation of myocardial function in coronary surgery patients

    NARCIS (Netherlands)

    de Hert, S. G.; ten Broecke, P. W.; Mertens, E.; Rodrigus, I. E.; Stockman, B. A.

    2002-01-01

    BACKGROUND: Phosphodiesterase III inhibitors increase myocardial contractility and decrease left ventricular (LV) afterload. We studied whether these effects altered LV response to an increase in cardiac load and affected length-dependent regulation of myocardial function. METHODS: Before the start

  18. Phosphodiesterase 4 inhibitor and phosphodiesterase 5 inhibitor combination therapy has antifibrotic and anti-inflammatory effects in mdx mice with Duchenne muscular dystrophy.

    Science.gov (United States)

    Nio, Yasunori; Tanaka, Masayuki; Hirozane, Yoshihiko; Muraki, Yo; Okawara, Mitsugi; Hazama, Masatoshi; Matsuo, Takanori

    2017-12-01

    Duchenne muscular dystrophy (DMD) is the most common inherited muscular dystrophy. Patients experience DMD in their 20s from cardiac or respiratory failure related to progressive muscle wasting. Currently, the only treatments for the symptoms of DMD are available. Muscle fibrosis, a DMD feature, leads to reduced muscle function and muscle mass, and hampers pharmaceutical therapeutic efficacy. Although antifibrotic agents may be useful, none is currently approved. Phosphodiesterase 4 (PDE4) inhibitors have exhibited antifibrotic effects in human and animal models. In this study, we showed beneficial effects of the PDE4 inhibitor piclamilast in the DMD mdx mouse. Piclamilast reduced the mRNA level of profibrotic genes, including collagen 1A1, in the gastrocnemius and diaphragm, in the mdx mouse, and significantly reduced the Sirius red staining area. The PDE5 inhibitors sildenafil and tadalafil ameliorated functional muscle ischemia in boys with DMD, and sildenafil reversed cardiac dysfunction in the mdx mouse. Single-treatment piclamilast or sildenafil showed similar antifibrotic effects on the gastrocnemius; combination therapy showed a potent antifibrotic effect, and piclamilast and combination therapy increased peroxisome proliferator-activated receptor γ coactivator-1α mRNA in mouse gastrocnemius. In summary, we confirmed that piclamilast has significant antifibrotic effects in mdx mouse muscle and is a potential treatment for muscle fibrosis in DMD.-Nio, Y., Tanaka, M., Hirozane, Y., Muraki, Y., Okawara, M., Hazama, M., Matsuo, T. Phosphodiesterase 4 inhibitor and phosphodiesterase 5 inhibitor combination therapy has antifibrotic and anti-inflammatory effects in mdx mice with Duchenne muscular dystrophy. © FASEB.

  19. Phosphodiesterase 4 inhibitors for chronic obstructive pulmonary disease.

    Science.gov (United States)

    Chong, Jimmy; Leung, Bonnie; Poole, Phillippa

    2017-09-19

    Chronic obstructive pulmonary disease (COPD) is associated with cough, sputum production or dyspnoea and a reduction in lung function, quality of life and life expectancy. Apart from smoking cessation, there are no other treatments that slow lung function decline. Roflumilast and cilomilast are oral phosphodiesterase 4 (PDE 4 ) inhibitors proposed to reduce the airway inflammation and bronchoconstriction seen in COPD. This is an update of a Cochrane review first published in 2011 and updated in 2013. To evaluate the efficacy and safety of oral PDE 4 inhibitors in the management of stable COPD. We identified randomised controlled trials (RCTs) from the Cochrane Airways Trials Register (date of last search October 2016). We found other trials from web-based clinical trials registers. We included RCTs if they compared oral PDE 4 inhibitors with placebo in people with COPD. We allowed co-administration of standard COPD therapy. One review author extracted data and a second review author checked the data. We reported pooled data in Review Manager as mean differences (MD), standardised mean differences (SMD) or odds ratios (OR). We converted the odds ratios into absolute treatment effects in a 'Summary of findings' table. Thirty-four separate RCTs studying roflumilast (20 trials with 17,627 participants) or cilomilast (14 trials with 6457 participants) met the inclusion criteria, with a duration of between six weeks and one year. These included people across international study centres with moderate to very severe COPD (Global Initiative for Chronic Obstructive Lung Disease (GOLD) grades II-IV), with a mean age of 64 years.We considered that the methodological quality of the 34 published and unpublished trials was acceptable overall. Treatment with a PDE 4 inhibitor was associated with a significant improvement in forced expiratory volume in one second (FEV 1 ) over the trial period compared with placebo (MD 51.53 mL, 95% confidence interval (CI) 43.17 to 59.90, 27

  20. Resveratrol Ameliorates Aging-Related Metabolic Phenotypes by Inhibiting cAMP Phosphodiesterases

    OpenAIRE

    Park, Sung-Jun; Ahmad, Faiyaz; Philp, Andrew; Baar, Keith; Williams, Tishan; Luo, Haibin; Ke, Hengming; Rehmann, Holger; Taussig, Ronald; Brown, Alexandra L.; Kim, Myung K.; Beaven, Michael A.; Burgin, Alex B.; Manganiello, Vincent; Chung, Jay H.

    2012-01-01

    Resveratrol, a polyphenol in red wine, has been reported as a calorie restriction mimetic with potential antiaging and antidiabetogenic properties. It is widely consumed as a nutritional supplement, but its mechanism of action remains a mystery. Here, we report that the metabolic effects of resveratrol result from competitive inhibition of cAMP-degrading phosphodiesterases, leading to elevated cAMP levels. The resulting activation of Epac1, a cAMP effector protein, increases intracellular Ca2...

  1. Purification and characterization of cGMP binding protein-phosphodiesterase from rat lung

    International Nuclear Information System (INIS)

    Francis, S.H.; Walseth, T.F.; Corbin, J.D.

    1986-01-01

    The cGMP binding protein-phosphodiesterase (cG-BPP) with a phosphodiesterase specific activity of 7 μM/min/mg has been purified from rat lung by sequential chromatography on DEAE-cellulose, Blue-Sepharose, zinc chelate affinity adsorbent and HPLC-DEAE. Migration of the major band on SDS-PAGE corresponds to a MW of ∼93,000. Both cGMP phosphodiesterase activity and cGMP binding from the HPLC-DEAE profile correlate with this band. Since the authors previous work has determined the native MW to be ∼177,000, this suggests a dimeric structure comprised of two 93,000 MW subunits for the rat lung cG-BPP. At low cGMP concentrations, cGMP binding is stimulated ∼20-fold by histone and ∼5-fold by 3-isobutyl-1-methylxanthine(IBMX). The purified protein has one component of cGMP dissociation with a rate constant of 0.045/min. Photolysis of the purified protein in the presence of 32 P-cGMP labels the 93,000 MW band and this labeling is increased by IBMX, indicating that the 93,000 MW band is a subunit of the cGMP-BPP. This implies that the enzyme preparation is nearly homogeneous, a conclusion also supported by a minimum [ 3 H]-cGMP binding stoichiometry of 0.5 mol per 93,000 subunit. An additional protein band with a MW of ∼90,000 also occurs in these preparations which exhibits behavior similar to the 93,000 MW protein. N 2 -Hexyl-cGMP inhibits phosphodiesterase activity by competing with cGMP for hydrolysis at the catalytic site but not at the binding site. N 2 -Hexyl cGMP actually increases cGMP binding. This provides the first evidence that cGMP binding is increased by compounds hydrolyzed at the catalytic site. This interaction between the binding and phosphodiesterase sites could be important in the regulation of the functions of these sites in vivo

  2. Overexpression screens identify conserved dosage chromosome instability genes in yeast and human cancer

    Science.gov (United States)

    Duffy, Supipi; Fam, Hok Khim; Wang, Yi Kan; Styles, Erin B.; Kim, Jung-Hyun; Ang, J. Sidney; Singh, Tejomayee; Larionov, Vladimir; Shah, Sohrab P.; Andrews, Brenda; Boerkoel, Cornelius F.; Hieter, Philip

    2016-01-01

    Somatic copy number amplification and gene overexpression are common features of many cancers. To determine the role of gene overexpression on chromosome instability (CIN), we performed genome-wide screens in the budding yeast for yeast genes that cause CIN when overexpressed, a phenotype we refer to as dosage CIN (dCIN), and identified 245 dCIN genes. This catalog of genes reveals human orthologs known to be recurrently overexpressed and/or amplified in tumors. We show that two genes, TDP1, a tyrosyl-DNA-phosphdiesterase, and TAF12, an RNA polymerase II TATA-box binding factor, cause CIN when overexpressed in human cells. Rhabdomyosarcoma lines with elevated human Tdp1 levels also exhibit CIN that can be partially rescued by siRNA-mediated knockdown of TDP1. Overexpression of dCIN genes represents a genetic vulnerability that could be leveraged for selective killing of cancer cells through targeting of an unlinked synthetic dosage lethal (SDL) partner. Using SDL screens in yeast, we identified a set of genes that when deleted specifically kill cells with high levels of Tdp1. One gene was the histone deacetylase RPD3, for which there are known inhibitors. Both HT1080 cells overexpressing hTDP1 and rhabdomyosarcoma cells with elevated levels of hTdp1 were more sensitive to histone deacetylase inhibitors valproic acid (VPA) and trichostatin A (TSA), recapitulating the SDL interaction in human cells and suggesting VPA and TSA as potential therapeutic agents for tumors with elevated levels of hTdp1. The catalog of dCIN genes presented here provides a candidate list to identify genes that cause CIN when overexpressed in cancer, which can then be leveraged through SDL to selectively target tumors. PMID:27551064

  3. Insulin alters the target size of the peripheral cyclic AMP phosphodiesterase but not the integral cyclic GMP-stimulated cyclic AMP phosphodiesterase in liver plasma membranes

    International Nuclear Information System (INIS)

    Wallace, A.V.; Martin, B.R.; Houslay, M.D.

    1990-01-01

    Radiation inactivation of the two high affinity cyclic AMP phosphodiesterases (PDE) found in liver plasma membranes afforded an estimation of their molecular target sizes in situ. The activity of the peripheral plasma membrane PDE decayed as a single exponential with a target size corresponding to a monomer of circa 54 kDa. The integral, cyclic GMP-stimulated PDE decayed as a dimer of circa 125 kDa. Preincubation of plasma membranes with insulin (10nM), prior to irradiation, caused the target size of only the peripheral plasma membrane PDE to increase. We suggest that insulin addition causes the peripheral plasma membrane PDE to alter its coupling to an integral plasma membrane protein with a target size of circa 90 kDa

  4. The search for mutations in the gene for the beta subunit of the cGMP phosphodiesterase (PDEB) in patients with autosomal recessive retinitis pigmentosa

    DEFF Research Database (Denmark)

    Riess, O; Noerremoelle, A; Weber, B

    1992-01-01

    The finding of a mutation in the beta subunit of the cyclic GMP (cGMP) phosphodiesterase gene causing retinal degeneration in mice (the Pdeb gene) prompted a search for disease-causing mutations in the human phosphodiesterase gene (PDEB gene) in patients with retinitis pigmentosa. All 22 exons...

  5. Effects of selective phosphodiesterases-4 inhibitors on learning and memory: a review of recent research.

    Science.gov (United States)

    Peng, Sheng; Sun, Haiyan; Zhang, Xiaoqing; Liu, Gongjian; Wang, Guanglei

    2014-09-01

    Phosphodiesterase-4 (PDE-4) regulates the intracellular level of cyclic adenosine monophosphate. Recent studies demonstrated that PDE-4 inhibitors can counteract deficits in long-term memory caused by aging or increased expression of mutant forms of human amyloid precursor proteins, and can influence the process of memory function and cognitive enhancement. Therapeutics, such as ketamine, a drug used in clinical anesthesia, can also cause memory deficits as adverse effects. Targeting PDE-4 with selective inhibitors may offer a novel therapeutic strategy to prevent, slow the progress, and, eventually, treat memory deficits.

  6. Distribution and function of 3',5'-Cyclic-AMP phosphodiesterases in the human ovary

    DEFF Research Database (Denmark)

    Petersen, T S; Kristensen, S G; Jeppesen, J V

    2015-01-01

    The concentration of the important second messenger cAMP is regulated by phosphodiesterases (PDEs) and hence an attractive drug target. However, limited human data are available about the PDEs in the ovary. The aim of the present study was to describe and characterise the PDEs in the human ovary....... Results were obtained by analysis of mRNA microarray data from follicles and granulosa cells (GCs), combined RT-PCR and enzymatic activity analysis in GCs, immunohistochemical analysis of ovarian sections and by studying the effect of PDE inhibitors on progesterone production from cultured GCs. We found...

  7. The inhibition of phosphodiesterase type 5 as a novel target for antidepressant action

    DEFF Research Database (Denmark)

    Liebenberg, Nico

    2010-01-01

    therapy of depression. A recent study from our laboratory reported an antidepressant-like response in the rat forced swim test (FST) following chronic (11 day) co-administration of the phosphodiesterase type 5 (PDE5) inhibitor sildenafil and the muscarinic acetylcholine (mACh) receptor antagonist atropine...... rats were treated with vehicle/drug(s) for 14 days, whereafter immobility, swimming and climbing behaviours were measured in the FST, or time spent in social interaction in the social interaction test. Following decapitation, saturation binding studies were performed for the measurement of m...

  8. Efficacy of B-Type Natriuretic Peptide Is Coupled to Phosphodiesterase 2A in Cardiac Sympathetic Neurons.

    Science.gov (United States)

    Li, Dan; Lu, Chieh-Ju; Hao, Guoliang; Wright, Hannah; Woodward, Lavinia; Liu, Kun; Vergari, Elisa; Surdo, Nicoletta C; Herring, Neil; Zaccolo, Manuela; Paterson, David J

    2015-07-01

    Elevated B-type natriuretic peptide (BNP) regulates cGMP-phosphodiesterase activity. Its elevation is regarded as an early compensatory response to cardiac failure where it can facilitate sympathovagal balance and cardiorenal homeostasis. However, recent reports suggest a paradoxical proadrenergic action of BNP. Because phosphodiesterase activity is altered in cardiovascular disease, we tested the hypothesis that BNP might lose its efficacy by minimizing the action of cGMP on downstream pathways coupled to neurotransmission. BNP decreased norepinephrine release from atrial preparations in response to field stimulation and also significantly reduced the heart rate responses to sympathetic nerve stimulation in vitro. Using electrophysiological recording and fluorescence imaging, BNP also reduced the depolarization evoked calcium current and intracellular calcium transient in isolated cardiac sympathetic neurons. Pharmacological manipulations suggested that the reduction in the calcium transient was regulated by a cGMP/protein kinase G pathway. Fluorescence resonance energy transfer measurements for cAMP, and an immunoassay for cGMP, showed that BNP increased cGMP, but not cAMP. In addition, overexpression of phosphodiesterase 2A after adenoviral gene transfer markedly decreased BNP stimulation of cGMP and abrogated the BNP responses to the calcium current, intracellular calcium transient, and neurotransmitter release. These effects were reversed on inhibition of phosphodiesterase 2A. Moreover, phosphodiesterase 2A activity was significantly elevated in stellate neurons from the prohypertensive rat compared with the normotensive control. Our data suggest that abnormally high levels of phosphodiesterase 2A may provide a brake against the inhibitory action of BNP on sympathetic transmission. © 2015 American Heart Association, Inc.

  9. Differential inhibition of calmodulin-sensitive phosphodiesterase and Ca++-adenosine triphosphatase by chlorpromazine-linked calmodulin

    International Nuclear Information System (INIS)

    Prozialeck, W.C.; Wallace, T.L.; Weiss, B.

    1987-01-01

    Upon irradiation with UV light, chlorpromazine binds irreversibly to calmodulin and inactivates it. To determine whether this chlorpromazine-calmodulin (CPZ-CaM) complex can inhibit the actions of native calmodulin, we examined its effects on the activity of calmodulin-sensitive cyclic nucleotide phosphodiesterase from rat brain and on the Ca++-adenosine triphosphatase (ATPase) of human erythrocyte membranes. The CPZ-CaM complex was prepared by irradiating purified bovine brain calmodulin in the presence of chlorpromazine and Ca++. The sample was then dialyzed extensively to remove reversibly bound chlorpromazine and then assayed for its ability to activate calmodulin-sensitive phosphodiesterase and Ca++-ATPase, and for its ability to block the stimulatory effects of native calmodulin on these enzymes. The CPZ-CaM complex had no effect on the basal activity of either enzyme; it neither activated nor inhibited the enzymes when assayed in the absence of calmodulin. However, it affected differentially the activation of the two enzymes by native calmodulin. The CPZ-CaM complex totally inhibited calmodulin-stimulated phosphodiesterase but had no effect on the activation of the ATPase by calmodulin. Other studies showed that CPZ-CaM increased the activation constant (Ka) for the interaction of calmodulin with phosphodiesterase but did not affect the maximal activation (Vmax) of the enzyme by calmodulin. Neither calmodulin nor CPZ-CaM altered the Km for the interaction between phosphodiesterase and cyclic AMP. These results suggest that CPZ-CaM inhibits the calmodulin-induced activation of phosphodiesterase by competing with calmodulin for regulatory sites on the enzyme and not by interacting with calmodulin itself or by blocking the interaction of cyclic AMP with the enzyme

  10. Effects of sevoflurane on adenylate cyclase and phosphodiesterases activity in brain of rats

    International Nuclear Information System (INIS)

    Feng Changdong; Yang Jianping; Dai Tijun

    2009-01-01

    Objective: To investigate the effects of sevoflurane on c adenylate cyclase (AC) and phosphodiesterases (PDE) activity in the cerebrocortex, hippocampus and brain stem of rats, and to examine the role of cAMP in sevoflurane anesthesia. Methods: Fourty SD rats were delaminately designed and allocated randomly to 5 groups inhaling 1.5% sevoflurane i.e., no recovery (recovery group, n=8) and one hour after righting reflexrecovery (aware group, n=8). The brain tissues were rapidly dissected into cerebrocortex and hippocampus and brain stem.Then the adenylate cyclase and phosphodiesterases activity were assessed. Results: So far as the activity of AC is concerned, compared with the control group, the activity of AC in the cerebrocortex, hippocampus and brain stem brain stem of induction group and anesthesia group, the cerebrocortex, and hippocampus in the recovery group were significantly increased; compared with those in the anesthesia group, the activity of AC in the cerebrocortex, hippocampus and brain stem of aware group were significantly decreased (P<0.05); For the activity of PDE, compared with the control group, the activity of PDE in the cerebrocortex, hippocampus and brain stem in the induction group and anesthesia group was significantly decreased, compared with that in anesthesia group, the activity of PDE in the cerebrocortex, hippocampus and brain stem of recovery group and aware group was significantly increased (P<0.05). Conclusion: cAMP may play an important role in sevoflurane anesthesia. (authors)

  11. Pathophysiology of visual disorders induced by phosphodiesterase inhibitors in the treatment of erectile dysfunction

    Directory of Open Access Journals (Sweden)

    Moschos MM

    2016-10-01

    Full Text Available Marilita M Moschos, Eirini Nitoda 1st Department of Ophthalmology, Medical School, National & Kapodistrian University of Athens, Athens, Greece Aim: The aim of this review was to summarize the ocular action of the most common phosphodiesterase (PDE inhibitors used for the treatment of erectile dysfunction and the subsequent visual disorders.Method: This is a literature review of several important articles focusing on the pathophysiology of visual disorders induced by PDE inhibitors.Results: PDE inhibitors have been associated with ocular side effects, including changes in color vision and light perception, blurred vision, transient alterations in electroretinogram (ERG, conjunctival hyperemia, ocular pain, and photophobia. Sildenafil and tadalafil may induce reversible increase in intraocular pressure and be involved in the development of nonarteritic ischemic optic neuropathy. Reversible idiopathic serous macular detachment, central serous chorioretinopathy, and ERG disturbances have been related to the significant impact of sildenafil and tadalafil on retinal perfusion.Discussion: So far, PDE inhibitors do not seem to cause permanent toxic effects on chorioretinal tissue and photoreceptors. However, physicians should write down any visual symptom observed during PDE treatment and refer the patients to ophthalmologists. Keywords: erectile dysfunction, pathophysiological mechanisms, phosphodiesterase inhibitors, PDE5, visual disorders

  12. Influence of GDP on interaction of transducin with cyclic nucleotide phosphodiesterase and rhodopsin from bovine retinal rods

    International Nuclear Information System (INIS)

    Rybin, V.O.

    1986-01-01

    In the presence of guanine nucleotides and rhodopsin-containing membranes from bovine retinal rod outer segments transducin stimulates light-sensitive cyclic nucleotide phosphodiesterase 5.5- to 7-fold. The activation constant (K/sub act/) for GTP and Gpp(NH)p is equal to 0.25 μM, while that for GDP and GDPβS is 14 and 110 μM, respectively. GDP free of admixtures of other nucleotides does not activate phosphodiesterase at concentrations up to 1 mM, but is bound to transducin and inhibits the Gpp(NH)p-dependent activation of phosphodiesterase. The nature of the interaction of transducin with depolarized rhodopsin also depends on the type of guanine nucleotide bound: in the presence of GDP rhodopsin-containing membranes bind 70-100% of the transducin, whereas in the presence of Gpp(NH)p only 13% of the protein is bound. The data obtained indicate that GDP and GTP convert transducin to two different functional states: the transducin-GTP complex is bound to phosphodiesterase and activates it, while the transducin-GDP complex is bound primarily to rhodopsin

  13. Immunohistochemical distribution of cAMP- and cGMP-phosphodiesterase (PDE) isoenzymes in the human prostate

    NARCIS (Netherlands)

    Uckert, Stefan; Oelke, Matthias; Stief, Christian G.; Andersson, K.-E.; Jonas, Udo; Hedlund, Petter

    2006-01-01

    With the introduction of sildenafil citrate (Viagra), the concept of phosphodiesterase (PDE) inhibition has gained tremendous interest in the field of urology. Cyclic nucleotide second messengers cGMP and cAMP have been assumed to be involved in the control of the normal function of the prostate.

  14. Structure of PhnP: a phosphodiesterase of the carbon-phosphorous lyase pathway for phosphonate degradation

    DEFF Research Database (Denmark)

    Podzelinska, Kateryna; He, Shu-Mei; Wathier, Matthew

    2009-01-01

    -dependent hydrolase of the ß-lactamase superfamily. Screening with a wide array of hydrolytically sensitive substrates indicated that PhnP is an enzyme with phosphodiesterase activity, having the greatest specificity toward bis(p-nitrophenyl)phosphate and 2',3'-cyclic nucleotides. No activity was observed toward RNA...

  15. 2'-phosphodiesterase and 2',5'-oligoadenylate synthetase activities in the lowest metazoans, sponge [porifera].

    Science.gov (United States)

    Saby, Emilie; Poulsen, Jesper Buchhave; Justesen, Just; Kelve, Merike; Uriz, Maria Jesus

    2009-01-01

    Sponges [porifera], the most ancient metazoans, contain modules related to the vertebrate immune system, including the 2',5'-oligoadenylate synthetase (OAS). The components of the antiviral 2',5'-oligoadenylate (2-5A) system (OAS, 2'-Phosphodiesterase (2'-PDE) and RNAse L) of vertebrates have not all been identified in sponges. Here, we demonstrate for the first time that in addition to the OAS activity, sponges possess a 2'-PDE activity, which highlights the probable existence of a premature 2-5A system. Indeed, Suberites domuncula and Crella elegans exhibited this 2-5A degrading activity. Upon this finding, two out of three elements forming the 2-5A system have been found in sponges, only a endoribonuclease, RNAse L or similar, has to be found. We suspect the existence of a complex immune system in sponges, besides the self/non-self recognition system and the use of phagocytosis and secondary metabolites against pathogens.

  16. Neuronal nitric oxide synthase supports Renin release during sodium restriction through inhibition of phosphodiesterase 3

    DEFF Research Database (Denmark)

    Sällström, Johan; Jensen, Boye L; Skøtt, Ole

    2010-01-01

    NOS supports renin release by cyclic guanosine monophosphate (cGMP)-mediated inhibition of cyclic adenosine monophosphate (cAMP)-specific phosphodiesterase 3 (PDE3) in juxtaglomerular (JG) cells. METHODS: The experiments were performed in conscious nNOS⁻(/)⁻ and wild types after 10 days on a low-sodium diet...... by measurements of inulin- and para-amino hippuric acid (PAH) clearances, respectively. RESULTS: The basal PRC was reduced in nNOS⁻(/)⁻ compared to the wild types. Administration of milrinone caused a more pronounced PRC increase in nNOS⁻(/)⁻, resulting in normalized renin levels, whereas PDE5 inhibition did...... not affect PRC in any genotype. The blood pressure was similar in both genotypes, and milrinone did not affect blood pressure compared to vehicle. GFR and RPF were similar at baseline and were reduced by milrinone. CONCLUSIONS: The present study provides in vivo evidence supporting the view that NO...

  17. Selective inhibition of phosphodiesterase 5 enhances glutamatergic synaptic plasticity and memory in mice.

    Science.gov (United States)

    Uthayathas, Subramaniam; Parameshwaran, Kodeeswaran; Karuppagounder, Senthilkumar S; Ahuja, Manuj; Dhanasekaran, Muralikrishnan; Suppiramaniam, Vishnu

    2013-11-01

    Phosphodiesterases (PDEs) belong to a family of proteins that control metabolism of cyclic nucleotides. Targeting PDE5, for enhancing cellular function, is one of the therapeutic strategies for male erectile dysfunction. We have investigated whether in vivo inhibition of PDE5, which is expressed in several brain regions, will enhance memory and synaptic transmission in the hippocampus of healthy mice. We have found that acute administration of sildenafil, a specific PDE5 inhibitor, enhanced hippocampus-dependent memory tasks. To elucidate the underlying mechanism in the memory enhancement, effects of sildenafil on long-term potentiation (LTP) were measured. The level of LTP was significantly elevated, with concomitant increases in basal synaptic transmission, in mice treated with sildenafil (1 mg/kg/day) for 15 days compared to control mice. These results suggest that moderate PDE5 inhibition enhances memory by increasing synaptic plasticity and transmission in the hippocampus. Copyright © 2013 Wiley Periodicals, Inc.

  18. Active site similarity between human and Plasmodium falciparum phosphodiesterases: considerations for antimalarial drug design

    Science.gov (United States)

    Howard, Brittany L.; Thompson, Philip E.; Manallack, David T.

    2011-08-01

    The similarity between Plasmodium falciparum phosphodiesterase enzymes ( PfPDEs) and their human counterparts have been examined and human PDE9A was found to be a suitable template for the construction of homology models for each of the four PfPDE isoforms. In contrast, the architecture of the active sites of each model was most similar to human PDE1. Molecular docking was able to model cyclic guanosine monophosphate (cGMP) substrate binding in each case but a docking mode supporting cyclic adenosine monophosphate (cAMP) binding could not be found. Anticipating the potential of PfPDE inhibitors as anti-malarial drugs, a range of reported PDE inhibitors including zaprinast and sildenafil were docked into the model of PfPDEα. The results were consistent with their reported biological activities, and the potential of PDE1/9 inhibitor analogues was also supported by docking.

  19. Synthesis of[11C]LY186126, an inhibitor of phosphodiesterase

    International Nuclear Information System (INIS)

    Prenant, C.; Crouzel, C.; Comar, D.; Robertson, D.W.

    1992-01-01

    LY186126 [1,3-dihydro-1,3,3-trimethyl-5-(1,4,5,6-tetrahydro-4-methyl-6-oxo-3-pyriddazinyl)-2H-indol-2-one ], an analogue of the cardiotonic agent indolidan, is a potent, selective and competitive inhibitor of an isozymic form of cyclic AMP phosphodiesterase. LY186126 was labelled with carbon-11 to permit pharmacological studies in the dog myocardium by positron emission tomography. Alkylation with [ 11 C]methyl iodide of N-norLY186126 (LY-197055) allowed the production of 1.7 GBq (50mCi) of [ 11 C]LY-186126 in 40 min. The product, was purified by HPLC. (author)

  20. Multiple Conformations of Phosphodiesterase-5: Implications for Enzyme Function and Drug Developement

    Energy Technology Data Exchange (ETDEWEB)

    Wang,H.; Liu, Y.; Huai, Q.; Cai, J.; Zoraghi, R.; Francis, S.; Corbin, J.; Robinson, H.; Xin, Z.; et al.

    2006-01-01

    Phosphodiesterase-5 (PDE5) is the target for sildenafil, vardenafil, and tadalafil, which are drugs for treatment of erectile dysfunction and pulmonary hypertension. We report here the crystal structures of a fully active catalytic domain of unliganded PDE5A1 and its complexes with sildenafil or icarisid II. These structures together with the PDE5A1-isobutyl-1-methylxanthine complex show that the H-loop (residues 660-683) at the active site of PDE5A1 has four different conformations and migrates 7 to 35 Angstroms upon inhibitor binding. In addition, the conformation of sildenafil reported herein differs significantly from those in the previous structures of chimerically hybridized or almost inactive PDE5. Mutagenesis and kinetic analyses confirm that the H-loop is particularly important for substrate recognition and that invariant Gly659 which immediately precedes the H-loop is critical for optimal substrate affinity and catalytic activity.

  1. An alpha-glucose-1-phosphate phosphodiesterase is present in rat liver cytosol

    International Nuclear Information System (INIS)

    Srisomsap, C.; Richardson, K.L.; Jay, J.C.; Marchase, R.B.

    1989-01-01

    UDP-glucose:glycoprotein glucose-1-phosphotransferase (Glc-phosphotransferase) catalyzes the transfer of alpha-Glc-1-P from UDP-Glc to mannose residues on acceptor glycoproteins. The predominant acceptor for this transfer in both mammalian cells and Paramecium is a cytoplasmic glycoprotein of 62-63 kDa. When cytoplasmic proteins from rat liver were fractionated by preparative isoelectric focusing following incubation of a liver homogenate with the 35S-labeled phosphorothioate analogue of UDP-Glc ([beta-35S]UDP-Glc), the acceptor was found to have a pI of about 6.0. This fraction, when not labeled prior to the focusing, became very heavily labeled when mixed with [beta-35S]. UDP-Glc and intact liver microsomes, a rich source of the Glc-phosphotransferase. In addition, it was observed that the isoelectric fractions of the cytosol having pI values of 2-3.2 contained a degradative activity, alpha-Glc-1-P phosphodiesterase, that was capable of removing alpha-Glc-1-P, monitored through radioactive labeling both in the sugar and the phosphate, as an intact unit from the 62-kDa acceptor. Identification of the product of this cleavage was substantiated by its partial transformation to UDP-Glc in the presence of UTP and UDP-Glc pyrophosphorylase. The alpha-Glc-1-P phosphodiesterase had a pH optimum of 7.5 and was not effectively inhibited by any of the potential biochemical inhibitors that were tested. Specificity for the Glc-alpha-1-P-6-Man diester was suggested by the diesterase's inability to degrade UDP-Glc or glucosylphosphoryldolichol. This enzyme may be important in the regulation of secretion since the alpha-Glc-1-P present on the 62-kDa phosphoglycoprotein appears to be removed and then rapidly replaced in response to secretagogue

  2. The devil is in the details: an analysis of the subtleties between phosphodiesterase inhibitors for erectile dysfunction.

    Science.gov (United States)

    Smith-Harrison, L I; Patel, Abhishek; Smith, Ryan P

    2016-04-01

    Erectile dysfunction (ED) is a common sexual disorder with numerous etiologies involving multiple organ systems that leads to significant distress and decreased quality of life for the affected men. Fortunately, there are several modalities and interventions for treating ED. Oral medications, intra-urethral compounds, intracorporeal injections, vacuum-assist devices and surgically implanted prostheses are all part of the treatment algorithm. One of the first-lines and certainly the most widely used options for treating ED is the family of oral phosphodiesterase type 5 inhibitors (PDE5I). The introduction of these medications in the late 1990s revolutionized the field of sexual medicine. Currently there are no guidelines and minimal literature to help providers choose among drugs in this class. This review will address differences in efficacy and side effects between various members of the oral selective phosphodiesterase-5 inhibitor class of drugs.

  3. Calmodulin-activated cyclic nucleotide phosphodiesterase from brain. Relationship of subunit structure to activity assessed by radiation inactivation

    International Nuclear Information System (INIS)

    Kincaid, R.L.; Kemdner, E.; Manganiello, V.C.; Osborne, J.C.; Vaughan, M.

    1981-01-01

    The apparent target sizes of the basal and calmodulin-dependent activities of calmodulin-activated phosphodiesterase from bovine brain were estimated using target theory analysis of data from radiation inactivation experiments. Whether crude or highly purified samples were irradiated, the following results were obtained. Low doses of radiation caused a 10 to 15% increase in basal activity, which, with further irradiation, decayed with an apparent target size of approx.60,000 daltons. Calmodulin-dependent activity decayed with an apparent target size of approx.105,000 daltons. The percentage stimulation of enzyme activity by calmodulin decreased markedly as a function of radiation dosage. These observations are consistent with results predicted by computer-assisted modeling based on the assumptions that: 1) the calmodulin-activated phosphodiesterase exists as a mixture of monomers which are fully active in the absence of calmodulin and dimers which are inactive in the absence of calmodulin; 2) in the presence of calmodulin, a dimer exhibits activity equal to that of two monomers; 3) on radiation destruction of a dimer, an active monomer is generated. This monomer-dimer hypothesis provides a plausible explanation for and definition of basal and calmodulin-dependent phosphodiesterase activity

  4. Minimally invasive monitoring of skeletal muscle hypermetabolism induced by the phosphodiesterase-III-inhibitor milrinone and sodium fluoride.

    Science.gov (United States)

    Schuster, Frank; Johannsen, Stephan; Roewer, Norbert; Anetseder, Martin

    2013-04-01

    We hypothesized that the phosphodiesterase-III-inhibitor milrinone and the non-specific G-protein activator sodium fluoride increase the skeletal muscular lactate levels as a sign of a hypermetabolic response. With approval of the local animal care committee Sprague-Dawley rats were killed and artificially perfused either with Ringer's solution or sodium fluoride 110 mM, while milrinone 1.32 mM or Ringer's solution at 1 μl/min was applied via microdialysis probes in both hind limbs. Lactate was measured spectrophotometrically in the dialysate. Baseline lactate levels before drug application did not differ between hind limbs. Local infusion of milrinone via microdialysis did not significantly increase intramuscular lactate concentrations compared with the Ringer control group. Muscular perfusion with sodium fluoride resulted in a significant increase of lactate and was potentiated by combination with local milrinone. Phosphodiesterase-III-inhibition alone does not significantly influence the lactate levels in skeletal muscle of sacrificed rats. Sodium fluoride infusion leads to an intramuscular lactate increase, which was further potentiated by local inhibition of phosphodiesterase-III. The fluoride-mediated hypermetabolic response following sodium fluoride could be a possible explanation for the observed myotoxic adverse effects in individuals treated by fluoride-containing agents. © 2012 The Authors. JPP © 2012. Royal Pharmaceutical Society.

  5. Lung vasodilatory response to inhaled iloprost in experimental pulmonary hypertension: amplification by different type phosphodiesterase inhibitors

    Directory of Open Access Journals (Sweden)

    Weissmann Norbert

    2005-07-01

    Full Text Available Abstract Inhaled prostanoids and phosphodiesterase (PDE inhibitors have been suggested for treatment of severe pulmonary hypertension. In catheterized rabbits with acute pulmonary hypertension induced by continuous infusion of the stable thromboxane analogue U46619, we asked whether sildenafil (PDE1/5/6 inhibitor, motapizone (PDE3 inhibitor or 8-Methoxymethyl-IBMX (PDE1 inhibitor synergize with inhaled iloprost. Inhalation of iloprost caused a transient pulmonary artery pressure decline, levelling off within per se ineffective dose of each PDE inhibitor (200 μg/kg × min 8-Methoxymethyl-IBMX, 1 μg/kg × min sildenafil, 5 μg/kg × min motapizone with subsequent iloprost nebulization, marked amplification of the prostanoid induced pulmonary vasodilatory response was noted and the area under the curve of PPA reduction was nearly threefold increased with all approaches, as compared to sole iloprost administration. Further amplification was achieved with the combination of inhaled iloprost with sildenafil plus motapizone, but not with sildenafil plus 8MM-IBMX. Systemic hemodynamics and gas exchange were not altered for all combinations. We conclude that co-administration of minute systemic doses of selective PDE inhibitors with inhaled iloprost markedly enhances and prolongs the pulmonary vasodilatory response to inhaled iloprost, with maintenance of pulmonary selectivity and ventilation perfusion matching. The prominent effect of sildenafil may be operative via both PDE1 and PDE5, and is further enhanced by co-application of a PDE3 inhibitor.

  6. 2'-phosphodiesterase and 2',5'-oligoadenylate synthetase activities in the lowest metazoans, sponge [porifera

    DEFF Research Database (Denmark)

    Saby, Emilie; Poulsen, Jesper Buchhave; Justesen, Just

    2009-01-01

    Sponges [porifera], the most ancient metazoans, contain modules related to the vertebrate immune system, including the 2′,5′-oligoadenylate synthetase (OAS). The components of the antiviral 2′,5′-oligoadenylate (2–5A) system (OAS, 2′-Phosphodiesterase (2′-PDE) and RNAse L) of vertebrates have...... not all been identified in sponges. Here, we demonstrate for the first time that in addition to the OAS activity, sponges possess a 2′-PDE activity, which highlights the probable existence of a premature 2–5A system. Indeed, Suberites domuncula and Crella elegans exhibited this 2–5A degrading activity....... Upon this finding, two out of three elements forming the 2–5A system have been found in sponges, only a endoribonuclease, RNAse L or similar, has to be found. We suspect the existence of a complex immune system in sponges, besides the self/non-self recognition system and the use of phagocytosis...

  7. Roles of A-Kinase Anchoring Proteins and Phosphodiesterases in the Cardiovascular System

    Science.gov (United States)

    Ercu, Maria; Klussmann, Enno

    2018-01-01

    A-kinase anchoring proteins (AKAPs) and cyclic nucleotide phosphodiesterases (PDEs) are essential enzymes in the cyclic adenosine 3′-5′ monophosphate (cAMP) signaling cascade. They establish local cAMP pools by controlling the intensity, duration and compartmentalization of cyclic nucleotide-dependent signaling. Various members of the AKAP and PDE families are expressed in the cardiovascular system and direct important processes maintaining homeostatic functioning of the heart and vasculature, e.g., the endothelial barrier function and excitation-contraction coupling. Dysregulation of AKAP and PDE function is associated with pathophysiological conditions in the cardiovascular system including heart failure, hypertension and atherosclerosis. A number of diseases, including autosomal dominant hypertension with brachydactyly (HTNB) and type I long-QT syndrome (LQT1), result from mutations in genes encoding for distinct members of the two classes of enzymes. This review provides an overview over the AKAPs and PDEs relevant for cAMP compartmentalization in the heart and vasculature and discusses their pathophysiological role as well as highlights the potential benefits of targeting these proteins and their protein-protein interactions for the treatment of cardiovascular diseases. PMID:29461511

  8. Effect of selective phosphodiesterase inhibitors on the rat eosinophil chemotactic response in vitro

    Directory of Open Access Journals (Sweden)

    Alves Alessandra C

    1997-01-01

    Full Text Available In the present study, we have performed a comparative analysis of the effect of selective inhibitors of phosphodiesterase (PDE type III, IV and V on eosinophil chemotaxis triggered by platelet activating factor (PAF and leukotriene B4 (LTB4 in vitro. The effect of the analogues N6-2'-O-dibutyryladenosine 3':5' cyclic monophosphate (Bt2 cyclic AMP and N2-2'-O- dibutyrylguanosine 3':5' cyclic monophosphate (Bt2 cyclic GMP has also been determined. The eosinophils were obtained from the peritoneal cavity of naive Wistar rats and purified in discontinuous Percoll gradients to 85-95% purity. We observed that pre-incubation of eosinophils with the PDE type IV inhibitor rolipram suppressed the chemotactic response triggered by PAF and LTB4, in association with an increase in the intracellular levels of cyclic AMP. In contrast, neither zaprinast (type V inhibitor nor type III inhibitors milrinone and SK&F 94836 affected the eosinophil migration. Only at the highest concentration tested did the analogue Bt2 cyclic AMP suppress the eosinophil chemotaxis, under conditions where Bt2 cyclic GMP was ineffective. We have concluded that inhibition of PDE IV, but not PDE III or V, was able to block the eosinophil chemotaxis in vitro, suggesting that the suppressive activity of selective PDE IV inhibitors on tissue eosinophil accumulation may, at least, be partially dependent on their ability to directly inhibit the eosinophil migration.

  9. [Comparison of the effects of phosphodiesterase III inhibitors, milrinone and olprinone, in infant corrective cardiac surgery].

    Science.gov (United States)

    Sakimura, Shotaro; Yoshino, Jun; Izumi, Kaoru; Jimi, Nobuo; Sumiyoshi, Rieko; Mizuno, Keiichiro

    2013-05-01

    Clinical characteristics of phosphodiesterase (PDE) III inhibitors, milrinone and olprinone, is not fully understood in infants. We therefore retrospectively examined the hemodynamics, metabolism, and oxygenation of two different PDE III inhibitors in infants undergoing radical correction of ventricular septal defect with pulmonary hypertension. Twenty-six infants with pulmonary hypertension undergoing ventricular septum defect repair were retrospectively allocated to milrinone group (n= 13)and olprinone group(n=13). Hemodynamic parameters, acid-base balance, oxygenation and postoperative mechanical ventilation period were compared between the two groups at induction of anesthesia, weaning from cardiopulmonary bypass and the end of the surgery. The patients' mean age was 4.4 +/- 2.5 months. Demographic data were almost similar between the two groups. Milrinone and olprinone were administered at the rates of 0.5 and 0.3 microg x kg-1 x min-1 at the end of surgery, respectively. Hemodynamic variables, acid-base balance, Pao2 /FIo2 ratio and mechanical ventilation period were not significantly different between the two groups. No adverse side effects were observed during the study period. The effects of the PDE III inhibitors, milrinone and olprinone, on hemodynamic parameters, acid-base balance and oxygenation were similar in these infants. Both milrinone and olprinone could be used safely in infant cardiac surgery.

  10. Effects of Intrarenal and Intravenous Infusion of the Phosphodiesterase 3 Inhibitor Milrinone on Renin Secretion

    Science.gov (United States)

    Kumagai, Kazuhiro; Reid, Ian A.

    1994-01-01

    We have reported that administration of the phosphodiesterase III inhibitor milrinone increases renin secretion in conscious rabbits. The aim of the present study was to determine if the increase in renin secretion results from a direct renal action of milrinone, or from an indirect extrarenal effect of the drug. This was accomplished by comparing the effects of intrarenal and intravenous infusion of graded doses of milrinone on plasma renin activity in unilaterally nephrectomized conscious rabbits. Milrinone was infused into the renal artery in doses of 0.01, 0.1 and 1.0 micro-g/kg/min, and intravenously in the same rabbits in doses of 0.01, 0.1, 1.0 and 10 micro-g/kg/min. Each dose was infused for 15 min. No intrarenal dose of milrinone altered plasma renin activity or arterial pressure, although at the highest dose, there was a small increase in heart rate. Intravenous infusion of milrinone at 1.0 micro-g/kg/min increased plasma renin activity to 176 +/- 55% of the control value (P less than 0.05). Heart rate increased but arterial pressure did not change. Intravenous infusion of milrinone at 1O micro-g/kg/min increased plasma renin activity to 386 +/- 193% of control in association with a decrease in arterial pressure and an increase in heart rate. These results confirm that milrinone increases renin secretion, and indicate that the stimulation is due to an extrarenal effect of the drug.

  11. Resveratrol ameliorates aging-related metabolic phenotypes by inhibiting cAMP phosphodiesterases.

    Science.gov (United States)

    Park, Sung-Jun; Ahmad, Faiyaz; Philp, Andrew; Baar, Keith; Williams, Tishan; Luo, Haibin; Ke, Hengming; Rehmann, Holger; Taussig, Ronald; Brown, Alexandra L; Kim, Myung K; Beaven, Michael A; Burgin, Alex B; Manganiello, Vincent; Chung, Jay H

    2012-02-03

    Resveratrol, a polyphenol in red wine, has been reported as a calorie restriction mimetic with potential antiaging and antidiabetogenic properties. It is widely consumed as a nutritional supplement, but its mechanism of action remains a mystery. Here, we report that the metabolic effects of resveratrol result from competitive inhibition of cAMP-degrading phosphodiesterases, leading to elevated cAMP levels. The resulting activation of Epac1, a cAMP effector protein, increases intracellular Ca(2+) levels and activates the CamKKβ-AMPK pathway via phospholipase C and the ryanodine receptor Ca(2+)-release channel. As a consequence, resveratrol increases NAD(+) and the activity of Sirt1. Inhibiting PDE4 with rolipram reproduces all of the metabolic benefits of resveratrol, including prevention of diet-induced obesity and an increase in mitochondrial function, physical stamina, and glucose tolerance in mice. Therefore, administration of PDE4 inhibitors may also protect against and ameliorate the symptoms of metabolic diseases associated with aging. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. The phosphodiesterase inhibitor, ibudilast, attenuates neuroinflammation in the MPTP model of Parkinson's disease.

    Directory of Open Access Journals (Sweden)

    Joanna Schwenkgrub

    Full Text Available Since the degeneration of the nigrostriatal dopaminergic pathway in Parkinson's disease (PD is associated with the inflammation process and decreased levels of cyclic nucleotides, inhibition of up-regulated cyclic nucleotide phosphodiesterases (PDEs appears to be a promising therapeutic strategy. We used ibudilast (IBD, a non-selective PDE3,4,10,11 inhibitor, due to the abundant PDE 4 and 10 expression in the striatum. The present study for the first time examined the efficacy of IBD in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP mouse model of PD.IBD [0, 20, 30, 40, or 50 mg/kg] was injected b.i.d. subcutaneously for nine days to three-month-old male C57Bl/10Tar mice, beginning two days prior to MPTP (60 mg/kg intoxication. High-pressure liquid chromatography, Western blot analysis, and real time RT-PCR methods were applied.Our study demonstrated that chronic administration of IBD attenuated astroglial reactivity and increased glial cell-derived neurotrophic factor (GDNF production in the striatum. Moreover, IBD reduced TNF-α, IL-6, and IL-1β expression.IBD had a well-defined effect on astroglial activation in the mouse model of PD; however, there was no protective effect in the acute phase of injury. Diminished inflammation and an increased level of GDNF may provide a better outcome in the later stages of neurodegeneration.

  13. Evaluation of the phosphodiesterase 3 inhibitor ORG 9935 as a contraceptive in female macaques: initial trials.

    Science.gov (United States)

    Jensen, Jeffrey T; Stouffer, Richard L; Stanley, Jessica E; Zelinski, Mary B

    2010-02-01

    The study was conducted to determine whether a phosphodiesterase (PDE) 3 inhibitor has potential as a novel contraceptive in primates. Regularly cycling adult female cynomolgus macaques of proven fertility (n=16) were treated for 7 months with placebo (controls) or the PDE3 inhibitor ORG 9935 as a daily food treat (150 mg/kg) or as a weekly depot injection (150 mg/kg, sc). After 1 month, a male of proven fertility was introduced into each group. Females underwent weekly monitoring of progesterone (P) and ultrasound evaluation for pregnancy if P remained elevated (1.0 ng/mL) >3 weeks. ORG 9935 values were evaluated using high-performance liquid chromatography. Overall, the pregnancy rate in ORG 9935-treated monkeys (4/8, 50%) did not differ from controls (7/8, 88%; p=.5). However, no animal became pregnant in a cycle when the serum level of ORG 9935 exceeded 300 nmol/L. Moreover, two treated monkeys who mated throughout the treatment phase and did not conceive became pregnant within four cycles after stopping ORG 9935. The other two animals were discontinued prematurely from the protocol. These results demonstrate that ORG 9935 may prevent pregnancy in primates at serum concentrations above 300 nmol/L and that the effect is reversible.

  14. Erektile Dysfunktion, Phosphodiesterase-5-Hemmer und KHK - die Sicht des Kardiologen

    Directory of Open Access Journals (Sweden)

    Schmid P

    2004-01-01

    Full Text Available Die erektile Dysfunktion (ED kommt vermehrt bei Patienten mit koronarer Herzkrankheit (KHK vor und wird üblicherweise mit Phosphodiesterase- 5-Hemmern (PDE-5-Hemmer wie Sildenafil, Vardenafil und Tadalafil behandelt. Dies geht mit einem systemischen Blutdruckabfall von bis zu 10 mmHg systolisch und bis 6 mmHg diastolisch einher. Die Herzfrequenz bleibt gleich oder steigt minimal an, das Doppelprodukt (RR sys x HF als Maß des myokardialen Sauerstoffverbrauches bleibt unverändert oder sinkt ab. Koronarangiographische Untersuchungen bei KHK-Patienten unter Sildenafil ergaben gegenüber Placebo keine Unterschiede in der Hämodynamik. Auch die Koronarreserve, die Blutflußgeschwindigkeit, der Durchmesser der Koronararterien, das Blutflußvolumen und der Koronargefäßwiderstand blieben unbeeinflußt. Die körperliche Leistungsfähigkeit wurde durch Sildenafil und Vardenafil nicht verändert. Eine kardiovaskuläre Exzeßmortalität liegt durch Einnahme von PDE-5-Hemmern nicht vor. Absolute Kontraindikation für eine Therapie mit PDE-5-Hemmern ist die gleichzeitige Gabe von NO-Donatoren (Nitrate, Molsidomin, Nitroprussid-Natrium, relative Kontraindikationen sind eine akute Koronarinsuffizienz, Herzinsuffizienz mit niedrigem Blutdruck, vorbestehende antihypertensive 3- bis 4-fach-Kombinationstherapie, Pharmaka, die den Abbau bzw. die Elimination von PDE-5-Hemmern reduzieren, sowie Antiarrhythmika der Klasse III.

  15. Imidazopyridine- and purine-thioacetamide derivatives: potent inhibitors of nucleotide pyrophosphatase/phosphodiesterase 1 (NPP1).

    Science.gov (United States)

    Chang, Lei; Lee, Sang-Yong; Leonczak, Piotr; Rozenski, Jef; De Jonghe, Steven; Hanck, Theodor; Müller, Christa E; Herdewijn, Piet

    2014-12-11

    Nucleotide pyrophosphatase/phosphodiesterase 1 (NPP1) belongs to the family of ecto-nucleotidases, which control extracellular nucleotide, nucleoside, and (di)phosphate levels. To study the (patho)physiological roles of NPP1 potent and selective inhibitors with drug-like properties are required. Therefore, a compound library was screened for NPP1 inhibitors using a colorimetric assay with p-nitrophenyl 5'-thymidine monophosphate (p-Nph-5'-TMP) as an artificial substrate. This led to the discovery of 2-(3H-imidazo[4,5-b]pyridin-2-ylthio)-N-(3,4-dimethoxyphenyl)acetamide (5a) as a hit compound with a Ki value of 217 nM. Subsequent structure-activity relationship studies led to the development of purine and imidazo[4,5-b]pyridine analogues with high inhibitory potency (Ki values of 5.00 nM and 29.6 nM, respectively) when assayed with p-Nph-5'-TMP as a substrate. Surprisingly, the compounds were significantly less potent when tested versus ATP as a substrate, with Ki values in the low micromolar range. A prototypic inhibitor was investigated for its mechanism of inhibition and found to be competitive versus both substrates.

  16. Usb1 controls U6 snRNP assembly through evolutionarily divergent cyclic phosphodiesterase activities.

    Science.gov (United States)

    Didychuk, Allison L; Montemayor, Eric J; Carrocci, Tucker J; DeLaitsch, Andrew T; Lucarelli, Stefani E; Westler, William M; Brow, David A; Hoskins, Aaron A; Butcher, Samuel E

    2017-09-08

    U6 small nuclear ribonucleoprotein (snRNP) biogenesis is essential for spliceosome assembly, but not well understood. Here, we report structures of the U6 RNA processing enzyme Usb1 from yeast and a substrate analog bound complex from humans. Unlike the human ortholog, we show that yeast Usb1 has cyclic phosphodiesterase activity that leaves a terminal 3' phosphate which prevents overprocessing. Usb1 processing of U6 RNA dramatically alters its affinity for cognate RNA-binding proteins. We reconstitute the post-transcriptional assembly of yeast U6 snRNP in vitro, which occurs through a complex series of handoffs involving 10 proteins (Lhp1, Prp24, Usb1 and Lsm2-8) and anti-cooperative interactions between Prp24 and Lhp1. We propose a model for U6 snRNP assembly that explains how evolutionarily divergent and seemingly antagonistic proteins cooperate to protect and chaperone the nascent snRNA during its journey to the spliceosome.The mechanism of U6 small nuclear ribonucleoprotein (snRNP) biogenesis is not well understood. Here the authors characterize the enzymatic activities and structures of yeast and human U6 RNA processing enzyme Usb1, reconstitute post-transcriptional assembly of yeast U6 snRNP in vitro, and propose a model for U6 snRNP assembly.

  17. cGMP-Phosphodiesterase Inhibition Prevents Hypoxia-Induced Cell Death Activation in Porcine Retinal Explants.

    Directory of Open Access Journals (Sweden)

    Lorena Olivares-González

    Full Text Available Retinal hypoxia and oxidative stress are involved in several retinal degenerations including diabetic retinopathy, glaucoma, central retinal artery occlusion, or retinopathy of prematurity. The second messenger cyclic guanosine monophosphate (cGMP has been reported to be protective for neuronal cells under several pathological conditions including ischemia/hypoxia. The purpose of this study was to evaluate whether the accumulation of cGMP through the pharmacological inhibition of phosphodiesterase (PDE with Zaprinast prevented retinal degeneration induced by mild hypoxia in cultures of porcine retina. Exposure to mild hypoxia (5% O2 for 24h reduced cGMP content and induced retinal degeneration by caspase dependent and independent (PARP activation mechanisms. Hypoxia also produced a redox imbalance reducing antioxidant response (superoxide dismutase and catalase activities and increasing superoxide free radical release. Zaprinast reduced mild hypoxia-induced cell death through inhibition of caspase-3 or PARP activation depending on the cell layer. PDE inhibition also ameliorated the effects of mild hypoxia on antioxidant response and the release of superoxide radical in the photoreceptor layer. The use of a PKG inhibitor, KT5823, suggested that cGMP-PKG pathway is involved in cell survival and antioxidant response. The inhibition of PDE, therefore, could be useful for reducing retinal degeneration under hypoxic/ischemic conditions.

  18. Phosphodiesterase 10A inhibition attenuates sleep deprivation-induced deficits in long-term fear memory.

    Science.gov (United States)

    Guo, Lengqiu; Guo, Zhuangli; Luo, Xiaoqing; Liang, Rui; Yang, Shui; Ren, Haigang; Wang, Guanghui; Zhen, Xuechu

    2016-12-02

    Sleep, particularly rapid eye movement (REM) sleep, is implicated in the consolidation of emotional memories. In the present study, we investigated the protective effects of a phosphodiesterase 10A (PDE10A) inhibitor MP-10 on deficits in long-term fear memory induced by REM sleep deprivation (REM-SD). REM-SD caused deficits in long-term fear memory, however, MP-10 administration ameliorated the deleterious effects of REM-SD on long term fear memory. Brain-derived neurotropic factor (BDNF) and phosphorylated cAMP response element-binding protein (pCREB) were altered in specific brain regions associated with learning and memory in REM-SD rats. Accordingly, REM-SD caused a significant decrease of pCREB in hippocampus and striatum and a significant decrease of BDNF in the hippocampus, striatum and amygdala, however, MP-10 reversed the effects of REM-SD in a dose-dependent manner. Our findings suggest that REM-SD disrupts the consolidation of long-term fear memory and that administration of MP-10 protects the REM-SD-induced deficits in fear memory, which may be due to the MP-10-induced expression of BDNF in the hippocampus, striatum and amygdala, and phosphorylation of CREB in the hippocampus and striatum. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. 2',3'-cyclic nucleotide 3'-phosphodiesterases inhibit hepatitis B virus replication.

    Directory of Open Access Journals (Sweden)

    Hui Ma

    Full Text Available 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP is a member of the interferon-stimulated genes, which includes isoforms CNP1 and CNP2. CNP1 is locally expressed in the myelin sheath but CNP2 is additionally expressed at low levels outside the nervous system. CNPs regulate multiple cellular functions and suppress protein production by association with polyadenylation of mRNA. Polyadenylation of Hepatitis B virus (HBV RNAs is crucial for HBV replication. Whether CNPs interact with polyadenylation signal of HBV RNAs and interfere HBV replication is unknown. In this study, we evaluated expressions of CNP isoforms in hepatoma cell lines and their effects on HBV replication. We found that CNP2 is moderately expressed and gently responded to interferon treatment in HepG2, but not in Huh7 cells. The CNP1 and CNP2 potently inhibited HBV production by blocking viral proteins synthesis and reducing viral RNAs, respectively. In chronic hepatitis B patients, CNP was expressed in most of HBV-infected hepatocytes of liver specimens. Knockdown of CNP expression moderately improved viral production in the HepG2.2.15 cells treated with IFN-α. In conclusion, CNP might be a mediator of interferon-induced response against HBV.

  20. Reduced Airway Hyperresponsiveness by Phosphodiesterase 3 and 4 Inhibitors in Guinea-Pigs

    Directory of Open Access Journals (Sweden)

    Nöella Germain

    1999-01-01

    Full Text Available The aim of the present study was to compare the effects of selective phosphodiesterase (PDE 3, 4 and 5 inhibitors on antigen-induced airway hyperresponsiveness in sensitized guinea-pigs. When the sensitized guinea-pigs were orally pre-treated with the selective PDE4 inhibitor, Ro 20-1724 (30 mg/kg, and studied 48 h after OA, a significant reduction (p<0.01 of the leftward shift of the dose-response curve to ACh was noted, whereas it was ineffective at the lower dose (10 mg/kg. Administration of the selective PDE3 inhibitor, milrinone (30 mg/kg also elicited a significant reduction (p<0.01 of the airway hyperresponsiveness, whereas the PDE5 inhibitor zaprinast (30 mg/kg was ineffective. These results show that both PDE3 and PDE4 inhibitors are able to inhibit the antigen-induced airway hyperresponsiveness in sensitized guinea-pigs and support the potential utility of selective PDE inhibitors in the treatment of asthma.

  1. An Insight into the Pharmacophores of Phosphodiesterase-5 Inhibitors from Synthetic and Crystal Structural Studies

    Energy Technology Data Exchange (ETDEWEB)

    Chen,G.; Wang, H.; Robinson, H.; Cai, J.; Wan, Y.; Ke, H.

    2008-01-01

    Selective inhibitors of cyclic nucleotide phosphodiesterase-5 (PDE5) have been used as drugs for treatment of male erectile dysfunction and pulmonary hypertension. An insight into the pharmacophores of PDE5 inhibitors is essential for development of second generation of PDE5 inhibitors, but has not been completely illustrated. Here we report the synthesis of a new class of the sildenafil derivatives and a crystal structure of the PDE5 catalytic domain in complex with 5-(2-ethoxy-5-(sulfamoyl)-3-thienyl)-1-methyl-3-propyl-1, 6-dihydro-7H-pyrazolo[4, 3-d]pyrimidin-7-one (12). Inhibitor 12 induces conformational change of the H-loop (residues 660-683), which is different from any of the known PDE5 structures. The pyrazolopyrimidinone groups of 12 and sildenafil are well superimposed, but their sulfonamide groups show a positional difference of as much as 1.5 Angstroms . The structure-activity analysis suggests that a small hydrophobic pocket and the H-loop of PDE5 are important for the inhibitor affinity, in addition to two common elements for binding of almost all the PDE inhibitors: the stack against the phenylalanine and the hydrogen bond with the invariant glutamine. However, the PDE5-12 structure does not provide a full explanation to affinity changes of the inhibitors. Thus alternatives such as conformational change of the M-loop are open and further structural study is required.

  2. Sildenafil preserves diastolic relaxation after reduction by L-NAME and increases phosphodiesterase-5 in the intercalated discs of cardiac myocytes and arterioles

    Directory of Open Access Journals (Sweden)

    Silvia Elaine Ferreira-Melo

    2011-01-01

    Full Text Available OBJECTIVES: We investigated the influence of sildenafil on cardiac contractility and diastolic relaxation and examined the distribution of phosphodiesterase-5 in the hearts of hypertensive rats that were treated with by NG-nitro-L-arginine methyl ester (L-NAME. METHODS: Male Wistar rats were treated with L-NAME and/or sildenafil for eight weeks. The Langendorff method was used to examine the effects of sildenafil on cardiac contractility and diastolic relaxation. The presence and location of phosphodiesterase-5 and phosphodiesterase-3 were assessed by immunohistochemistry, and cGMP plasma levels were measured by ELISA. RESULTS: In isolated hearts, sildenafil prevented the reduction of diastolic relaxation (dP/dt that was induced by L-NAME. In addition, phosphodiesterase-5 immunoreactivity was localized in the intercalated discs between the myocardial cells. The staining intensity was reduced by L-NAME, and sildenafil treatment abolished this reduction. Consistent with these results, the plasma levels of cGMP were decreased in the L-NAME-treated rats but not in rats that were treated with L-NAME + sildenafil. CONCLUSION: The sildenafil-induced attenuation of the deleterious hemodynamic and cardiac morphological effects of L-NAME in cardiac myocytes is mediated (at least in part by the inhibition of phosphodiesterase-5.

  3. Stress history increases alcohol intake in relapse: relation to phosphodiesterase 10A.

    Science.gov (United States)

    Logrip, Marian L; Zorrilla, Eric P

    2012-09-01

    Stressful experiences can result in elevated alcohol drinking, as exemplified in many individuals with post-traumatic stress disorder. However, how stress history, rather than acute stressors, influences alcohol intake remains uncertain. To model the protracted effects of past stress, male Wistar rats were subjected to light-cued footshock (stress history) or light cues alone (control) prior to acquisition of alcohol self-administration (1-hour sessions, fixed ratio 1-3, 100 µl of 10% v/v alcohol as reinforcer). Stress history did not alter mean alcohol intake during acquisition of self-administration, but it increased preference for the alcohol-paired lever over the inactive lever. Following an extinction period, rats with a history of stress exposure and low baseline alcohol intake showed a twofold elevation in alcohol self-administration, as compared with low-drinking rats with no stress history. Similar effects were not seen in rats self-administering 0.1% sucrose. Analysis of mRNA levels of phosphodiesterase 10A (PDE10A), a dual-specificity cyclic adenosine monophosphate and cyclic guanosine monophosphate hydrolyzing enzyme, showed that stress history increased Pde10a mRNA levels in the basolateral amygdala and, in low-drinking rats, the prelimbic prefrontal cortex (plPFC). Pde10a mRNA levels in the plPFC correlated directly with greater alcohol self-administration during the relapse-like phase, and greater BLA Pde10a mRNA levels correlated with increased ethanol preference after acquisition. The data demonstrate that stress history sensitizes otherwise low alcohol drinkers to consume more alcohol in a relapse-like situation and identify stress-induced neuroadaptations in amygdala and prefrontal cortical Pde10a expression as changes that may drive heightened alcohol intake and preference in susceptible individuals. © 2012 The Authors. Addiction Biology © 2012 Society for the Study of Addiction.

  4. Inhibition of Cyclic Adenosine Monophosphate-Specific Phosphodiesterase by Various Food Plant-Derived Phytotherapeutic Agents.

    Science.gov (United States)

    Röhrig, Teresa; Pacjuk, Olga; Hernández-Huguet, Silvia; Körner, Johanna; Scherer, Katharina; Richling, Elke

    2017-11-04

    Background: Phosphodiesterases (PDEs) play a major role in the regulation of cyclic adenosine monophosphate (cAMP)- and cyclic guanosine monophosphate (cGMP)-mediated pathways. Their inhibitors exhibit anti-inflammatory, vasodilatory and antithrombotic effects. Therefore, consumption of foods with PDE-inhibiting potential may possess beneficial influence on the risk of cardiovascular diseases. Methods: Four plant extracts ( Arbutus unedo , Camellia sinensis , Cynara scolymus , Zingiber officinale ) with promising ingredient profiles and physiological effects were tested for their ability to inhibit cAMP-specific PDE in vitro in a radioactive assay. Results: Strawberry tree fruit ( Arbutus unedo ) and tea ( Camellia sinensis ) extracts did not inhibit PDE markedly. Alternatively, artichoke ( Cynara scolymus ) extract had a significant inhibitory influence on PDE activity (IC 50 = 0.9 ± 0.1 mg/mL) as well as its flavone luteolin (IC 50 = 41 ± 10 μM) and 3,4-dicaffeoylquinic acid (IC 50 > 1.0 mM). Additionally, the ginger ( Zingiber officinale ) extract and one of its constituents, [6]-gingerol, significantly inhibited PDE (IC 50 = 1.7 ± 0.2 mg/mL and IC 50 > 1.7 mM, respectively). Crude fractionation of ginger extract showed that substances responsible for PDE inhibition were in the lipoid fraction (IC 50 = 455 ± 19 μg/mL). Conclusions: A PDE-inhibitory effect was shown for artichoke and ginger extract. Whether PDE inhibition in vivo can be achieved through ingestion of artichoke or ginger extracts leading to physiological effects concerning cardiovascular health should be addressed in future research.

  5. Inhibition of Cyclic Adenosine Monophosphate-Specific Phosphodiesterase by Various Food Plant-Derived Phytotherapeutic Agents

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    Teresa Röhrig

    2017-11-01

    Full Text Available Background: Phosphodiesterases (PDEs play a major role in the regulation of cyclic adenosine monophosphate (cAMP- and cyclic guanosine monophosphate (cGMP-mediated pathways. Their inhibitors exhibit anti-inflammatory, vasodilatory and antithrombotic effects. Therefore, consumption of foods with PDE-inhibiting potential may possess beneficial influence on the risk of cardiovascular diseases. Methods: Four plant extracts (Arbutus unedo, Camellia sinensis, Cynara scolymus, Zingiber officinale with promising ingredient profiles and physiological effects were tested for their ability to inhibit cAMP-specific PDE in vitro in a radioactive assay. Results: Strawberry tree fruit (Arbutus unedo and tea (Camellia sinensis extracts did not inhibit PDE markedly. Alternatively, artichoke (Cynara scolymus extract had a significant inhibitory influence on PDE activity (IC50 = 0.9 ± 0.1 mg/mL as well as its flavone luteolin (IC50 = 41 ± 10 μM and 3,4-dicaffeoylquinic acid (IC50 > 1.0 mM. Additionally, the ginger (Zingiber officinale extract and one of its constituents, [6]-gingerol, significantly inhibited PDE (IC50 = 1.7 ± 0.2 mg/mL and IC50 > 1.7 mM, respectively. Crude fractionation of ginger extract showed that substances responsible for PDE inhibition were in the lipoid fraction (IC50 = 455 ± 19 μg/mL. Conclusions: A PDE-inhibitory effect was shown for artichoke and ginger extract. Whether PDE inhibition in vivo can be achieved through ingestion of artichoke or ginger extracts leading to physiological effects concerning cardiovascular health should be addressed in future research.

  6. Phosphodiesterase inhibitors enhance object memory independent of cerebral blood flow and glucose utilization in rats.

    Science.gov (United States)

    Rutten, Kris; Van Donkelaar, Eva L; Ferrington, Linda; Blokland, Arjan; Bollen, Eva; Steinbusch, Harry Wm; Kelly, Paul At; Prickaerts, Jos Hhj

    2009-07-01

    Phosphodiesterase (PDE) inhibitors prevent the breakdown of the second messengers, cyclic AMP (cAMP) and cyclic GMP (cGMP), and are currently studied as possible targets for cognitive enhancement. Earlier studies indicated beneficial effects of PDE inhibitors in object recognition. In this study we tested the effects of three PDE inhibitors on spatial memory as assessed in a place and object recognition task. Furthermore, as both cAMP and cGMP are known vasodilators, the effects of PDE inhibition on cognitive functions could be explained by enhancement of cerebrovascular function. We examined this possibility by measuring the effects of PDE5 and PDE4 inhibitor treatment on local cerebral blood flow and glucose utilization in rats using [14C]-iodoantipyrine and [14C]-2-deoxyglucose quantitative autoradiography, respectively. In the spatial location task, PDE5 inhibition (cGMP) with vardenafil enhanced only early phase consolidation, PDE4 inhibition (cAMP) with rolipram enhanced only late phase consolidation, and PDE2 inhibition (cAMP and cGMP) with Bay 60-7550 enhanced both consolidation processes. Furthermore, PDE5 inhibition had no cerebrovascular effects in hippocampal or rhinal areas. PDE4 inhibition increased rhinal, but not hippocampal blood flow, whereas it decreased glucose utilization in both areas. In general, PDE5 inhibition decreased the ratio between blood flow and glucose utilization, indicative of general oligaemia; whereas PDE4 inhibition increased this ratio, indicative of general hyperemia. Both oligaemic and hyperemic conditions are detrimental for brain function and do not explain memory enhancement. These results underscore the specific effects of cAMP and cGMP on memory consolidation (object and spatial memory) and provide evidence that the underlying mechanisms of PDE inhibition on cognition are independent of cerebrovascular effects.

  7. Phosphodiesterase type 5 inhibitors increase Herceptin transport and treatment efficacy in mouse metastatic brain tumor models.

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    Jinwei Hu

    2010-04-01

    Full Text Available Chemotherapeutic drugs and newly developed therapeutic monoclonal antibodies are adequately delivered to most solid and systemic tumors. However, drug delivery into primary brain tumors and metastases is impeded by the blood-brain tumor barrier (BTB, significantly limiting drug use in brain cancer treatment.We examined the effect of phosphodiesterase 5 (PDE5 inhibitors in nude mice on drug delivery to intracranially implanted human lung and breast tumors as the most common primary tumors forming brain metastases, and studied underlying mechanisms of drug transport. In vitro assays demonstrated that PDE5 inhibitors enhanced the uptake of [(14C]dextran and trastuzumab (Herceptin, a humanized monoclonal antibody against HER2/neu by cultured mouse brain endothelial cells (MBEC. The mechanism of drug delivery was examined using inhibitors for caveolae-mediated endocytosis, macropinocytosis and coated pit/clathrin endocytosis. Inhibitor analysis strongly implicated caveolae and macropinocytosis endocytic pathways involvement in the PDE5 inhibitor-enhanced Herceptin uptake by MBEC. Oral administration of PDE5 inhibitor, vardenafil, to mice with HER2-positive intracranial lung tumors led to an increased tumor permeability to high molecular weight [(14C]dextran (2.6-fold increase and to Herceptin (2-fold increase. Survival time of intracranial lung cancer-bearing mice treated with Herceptin in combination with vardenafil was significantly increased as compared to the untreated, vardenafil- or Herceptin-treated mice (p0.05.These findings suggest that PDE5 inhibitors may effectively modulate BTB permeability, and enhance delivery and therapeutic efficacy of monoclonal antibodies in hard-to-treat brain metastases from different primary tumors that had metastasized to the brain.

  8. First-generation phosphodiesterase type 5 inhibitors dropout: a comprehensive review and meta-analysis.

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    Corona, G; Rastrelli, G; Burri, A; Serra, E; Gianfrilli, D; Mannucci, E; Jannini, E A; Maggi, M

    2016-11-01

    The discontinuation rate with phosphodiesterase type 5 inhibitors (PDE5i) remains very high. The aim of this study was to review and meta-analyze currently available data regarding dropout of the first-generation of PDE5i including sildenafil, vardenafil, and tadalafil. An extensive Medline Embase and Cochrane search was performed including the following words: 'PDE5i', 'discontinuation'. All observational studies reporting the dropout rate of PDE5i and its specific causes without any arbitrary restrictions were included. Out of 103 retrieved articles, 22 were included in the study. Retrieved trials included a total of 162,936 patients with a mean age of 58.8 ± 7.9 years. Prevalence of reported comorbid diabetes and hypertension were 27.7% and 36.9%, respectively. PDE5i were associated with a mean discontinuation rate of 4% per month (almost 50% after one year). This rate was higher in younger subjects and in those reporting a higher prevalence of associated morbidities. Six main reasons of PDE5i dropout were identified in the evaluated trials. Partner-related problems and lack of efficacy represented the most important reasons for PDE5i discontinuation, although no significant difference among factors was detected. In conclusion, despite their high efficacy and easy administration, the discontinuation rate and dissatisfaction with PDE5i are still very high. Our data showed that no single factor plays a major role in PDE5i dropout, suggesting that the discontinuation rate is usually because of a combination of both medical problems and psychosocial and relational factors. © 2016 American Society of Andrology and European Academy of Andrology.

  9. Characterization of the insulin-sensitive low Km cAMP phosphodiesterase from rat adipose tissue

    International Nuclear Information System (INIS)

    Degerman, E.; Belfrage, P.; Manganiello, V.C.

    1986-01-01

    Particulate, but not soluble, low K/sub m/ cAMP phosphodiesterase (PDE) activity of rat adipocytes was increased 50-100% during incubation (10 min) of intact cells with 1-3 nM insulin; activation was less with higher or lower insulin concentrations. Activation was maintained during solubilization with an alkyl polyoxyethylene non-ionic detergent C 13 , E 12 and NaBr and chromatography on DEAE. Enzyme from DEAE was further purified by chromatography on Sepahadex G-200 and Blue-Sepharose. Activity (with 0.5 μM [ 3 H]cAMP) was rather sensitive to inhibition by p-chloromercuribenzoate (IC 50 , 1 μM) and less so by 2,2'-dithiobis-(5-nitropyridine) (160 μM), N-ethylmaleimide (525 μM) and iodoacetamide (750 μM). PDE activity was also rather sensitive to inhibition by cilostamide (IC 50 , ∼40 nM) and the cardiotonic drugs CI 930 (450 nM) and milrinone (630 nM) but rather insensitive to RO 20-1724 (190 μM). Based on effects of these inhibitors, the hormone-sensitive low K/sub m/ particulate cAMP PDE from rat adipocytes seems to be analogous to the insulin-activated particulate PDE from 3T3-L1 adipocytes and the cilostamide-sensitive soluble low K/sub m/ cAMP PDE from bovine liver (designated as III-C), platelets, heart, and other tissues

  10. Inhibition of phosphodiesterase 4 reduces ethanol intake and preference in C57BL/6J mice

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    Yuri A. Blednov

    2014-05-01

    Full Text Available Some anti-inflammatory medications reduce alcohol consumption in rodent models. Inhibition of phosphodiesterases (PDE increases cAMP and reduces inflammatory signaling. Rolipram, an inhibitor of PDE4, markedly reduced ethanol intake and preference in mice and reduced ethanol seeking and consumption in alcohol-preferring fawn-hooded rats (Hu et al., 2011;Wen et al., 2012. To determine if these effects were specific for PDE4, we compared nine PDE inhibitors with different subtype selectivity: propentofylline (nonspecific, vinpocetine (PDE1, olprinone, milrinone (PDE3, zaprinast (PDE5, rolipram, mesopram, piclamilast, and CDP840 (PDE4. Alcohol intake was measured in C57BL/6J male mice using 24-hour two-bottle choice and two-bottle choice with limited (three-hour access to alcohol. Only the selective PDE4 inhibitors reduced ethanol intake and preference in the 24-hour two-bottle choice test. For rolipram, piclamilast, and CDP840, this effect was observed after the first 6 hours but not after the next 18 hours. Mesopram, however, produced a long-lasting reduction of ethanol intake and preference. In the limited access test, rolipram, piclamilast, and mesopram reduced ethanol consumption and total fluid intake and did not change preference for ethanol, whereas CDP840 reduced both consumption and preference without altering total fluid intake. Our results provide novel evidence for a selective role of PDE4 in regulating ethanol drinking in mice. We suggest that inhibition of PDE4 may be an unexplored target for medication development to reduce excessive alcohol consumption.

  11. Characterization of the insulin-sensitive low Km cAMP phosphodiesterase from rat adipose tissue

    Energy Technology Data Exchange (ETDEWEB)

    Degerman, E.; Belfrage, P.; Manganiello, V.C.

    1986-05-01

    Particulate, but not soluble, low K/sub m/ cAMP phosphodiesterase (PDE) activity of rat adipocytes was increased 50-100% during incubation (10 min) of intact cells with 1-3 nM insulin; activation was less with higher or lower insulin concentrations. Activation was maintained during solubilization with an alkyl polyoxyethylene non-ionic detergent C/sub 13/, E/sub 12/ and NaBr and chromatography on DEAE. Enzyme from DEAE was further purified by chromatography on Sepahadex G-200 and Blue-Sepharose. Activity (with 0.5 ..mu..M (/sup 3/H)cAMP) was rather sensitive to inhibition by p-chloromercuribenzoate (IC/sub 50/, 1 ..mu..M) and less so by 2,2'-dithiobis-(5-nitropyridine) (160 ..mu..M), N-ethylmaleimide (525 ..mu..M) and iodoacetamide (750 ..mu..M). PDE activity was also rather sensitive to inhibition by cilostamide (IC/sub 50/, approx.40 nM) and the cardiotonic drugs CI 930 (450 nM) and milrinone (630 nM) but rather insensitive to RO 20-1724 (190 ..mu..M). Based on effects of these inhibitors, the hormone-sensitive low K/sub m/ particulate cAMP PDE from rat adipocytes seems to be analogous to the insulin-activated particulate PDE from 3T3-L1 adipocytes and the cilostamide-sensitive soluble low K/sub m/ cAMP PDE from bovine liver (designated as III-C), platelets, heart, and other tissues.

  12. The role of cilostazol, a phosphodiesterase 3 inhibitor, on oocyte maturation and subsequent pregnancy in mice.

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    Min Li

    Full Text Available It is important to identify effective contraceptive drugs that cause minimal disruption to physiological processes. Phosphodiesterase 3 (PDE3 inhibitors suppress meiosis in oocytes by decreasing the level of cAMP and blocking the extrusion of the first polar body. In this study, we tested the PDE3 inhibitor, cilostazol, as a potential contraceptive agent. The effects of cilostazol treatment in vitro and in vivo on the suppression of oocyte maturation in a mouse model were investigated. The results indicated that treatment with increasing concentrations of cilostazol led to a dose-dependent arrest in meiosis progression. The effective in vitro concentration was 1 µM and was 300 mg/kg in vivo. The effect of cilostazol was reversible. After removal of the drug, meiosis resumed and mouse oocytes matured in vitro, and showed normal chromosome alignment and spindle organization. After fertilization using an ICSI method, the oocytes showed normal morphology, fertilization rate, embryo cleavage, blastocyst formation, and number of viable pups when compared with controls. The offspring showed similar body weight and fertility. In vivo, the mice became infertile if the drug was injected sequentially, and became pregnant following discontinuation of cilostazol. More importantly, no side effects of cilostazol were observed in treated female mice as demonstrated by blood pressure and heart rate monitoring. It is concluded that cilostazol, a drug routinely used for intermittent claudication, can effectively inhibit oocyte maturation in vitro and in vivo, does not affect the developmental potential of oocytes following drug removal and has few side effects in female mice treated with this drug. These findings suggest that cilostazol may be a potential new contraceptive agent that may facilitate an efficacy and safety study of this drug.

  13. Phosphodiesterase type 4 inhibitor rolipram improves survival of spiral ganglion neurons in vitro.

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    Katharina Kranz

    Full Text Available Sensorineural deafness is caused by damage of hair cells followed by degeneration of the spiral ganglion neurons and can be moderated by cochlear implants. However, the benefit of the cochlear implant depends on the excitability of the spiral ganglion neurons. Therefore, current research focuses on the identification of agents that will preserve their degeneration. In this project we investigated the neuroprotective effect of Rolipram as a promising agent to improve the viability of the auditory neurons. It is a pharmaceutical agent that acts by selective inhibition of the phosphodiesterase 4 leading to an increase in cyclic AMP. Different studies reported a neuroprotective effect of Rolipram. However, its significance for the survival of SGN has not been reported so far. Thus, we isolated spiral ganglion cells of neonatal rats for cultivation with different Rolipram concentrations and determined the neuronal survival rate. Furthermore, we examined immunocytologically distinct proteins that might be involved in the neuroprotective signalling pathway of Rolipram and determined endogenous BDNF by ELISA. When applied at a concentration of 0.1 nM, Rolipram improved the survival of SGN in vitro. According to previous studies, our immunocytological data showed that Rolipram application induces the phosphorylation and thereby activation of the transcription factor CREB. This activation can be mediated by the cAMP-PKA-signalling pathway as well as via ERK as a part of the MAP-kinase pathway. However, only in cultures pre-treated with BDNF, an endogenous increase of BDNF was detected. We conclude that Rolipram has the potential to improve the vitality of neonatal auditory nerve cells in vitro. Further investigations are necessary to prove the effect of Rolipram in vivo in the adult organism after lesion of the hair cells and insertion of cochlear implants.

  14. Synthesis, Pharmacological Profile and Docking Studies of New Sulfonamides Designed as Phosphodiesterase-4 Inhibitors.

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    Isabelle Karine da Costa Nunes

    Full Text Available Prior investigations showed that increased levels of cyclic AMP down-regulate lung inflammatory changes, stimulating the interest in phosphodiesterase (PDE4 as therapeutic target. Here, we described the synthesis, pharmacological profile and docking properties of a novel sulfonamide series (5 and 6a-k designed as PDE4 inhibitors. Compounds were screened for their selectivity against the four isoforms of human PDE4 using an IMAP fluorescence polarized protocol. The effect on allergen- or LPS-induced lung inflammation and airway hyper-reactivity (AHR was studied in A/J mice, while the xylazine/ketamine-induced anesthesia test was employed as a behavioral correlate of emesis in rodents. As compared to rolipram, the most promising screened compound, 6a (LASSBio-448 presented a better inhibitory index concerning PDE4D/PDE4A or PDE4D/PDE4B. Accordingly, docking analyses of the putative interactions of LASSBio-448 revealed similar poses in the active site of PDE4A and PDE4C, but slight unlike orientations in PDE4B and PDE4D. LASSBio-448 (100 mg/kg, oral, 1 h before provocation, inhibited allergen-induced eosinophil accumulation in BAL fluid and lung tissue samples. Under an interventional approach, LASSBio-448 reversed ongoing lung eosinophilic infiltration, mucus exacerbation, peribronchiolar fibrosis and AHR by allergen provocation, in a mechanism clearly associated with blockade of pro-inflammatory mediators such as IL-4, IL-5, IL-13 and eotaxin-2. LASSBio-448 (2.5 and 10 mg/kg also prevented inflammation and AHR induced by LPS. Finally, the sulfonamide derivative was shown to be less pro-emetic than rolipram and cilomilast in the assay employed. These findings suggest that LASSBio-448 is a new PDE4 inhibitor with marked potential to prevent and reverse pivotal pathological features of diseases characterized by lung inflammation, such as asthma.

  15. Clinical and preclinical treatment of urologic diseases with phosphodiesterase isoenzymes 5 inhibitors: an update

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    Wen-Hao Zhang

    2016-01-01

    Full Text Available Phosphodiesterase isoenzymes 5 inhibitors (PDE5-Is are the first-line therapy for erectile dysfunction (ED. The constant discoveries of nitric oxide (NO/cyclic guanosine monophosphate (cGMP cell-signaling pathway for smooth muscle (SM control in other urogenital tracts (UGTs make PDE5-Is promising pharmacologic agents against other benign urological diseases. This article reviews the literature and contains some previously unpublished data about characterizations and activities of PDE5 and its inhibitors in treating urological disorders. Scientific discoveries have improved our understanding of cell-signaling pathway in NO/cGMP-mediated SM relaxation in UGTs. Moreover, the clinical applications of PDE5-Is have been widely recognized. On-demand PDE5-Is are efficacious for most cases of ED, while daily-dosing and combination with testosterone are recommended for refractory cases. Soluble guanylate cyclase (sGC stimulators also have promising role in the management of severe ED conditions. PDE5-Is are also the first rehabilitation strategy for postoperation or postradiotherapy ED for prostate cancer patients. PDE5-Is, especially combined with α-adrenoceptor antagonists, are very effective for benign prostatic hyperplasia (BPH except on maximum urinary flow rate (Q max with tadalafil recently proved for BPH with/without ED. Furthermore, PDE5-Is are currently under various phases of clinical or preclinical researches with promising potential for other urinary and genital illnesses, such as priapism, premature ejaculation, urinary tract calculi, overactive bladder, Peyronie′s disease, and female sexual dysfunction. Inhibition of PDE5 is expected to be an effective strategy in treating benign urological diseases. However, further clinical studies and basic researches investigating mechanisms of PDE5-Is in disorders of UGTs are required.

  16. Mice deficient in phosphodiesterase-4A display anxiogenic-like behavior.

    Science.gov (United States)

    Hansen, Rolf T; Conti, Marco; Zhang, Han-Ting

    2014-08-01

    Phosphodiesterases (PDEs) are a super family of enzymes responsible for the halting of intracellular cyclic nucleotide signaling and may represent novel therapeutic targets for treatment of cognitive disorders. PDE4 is of considerable interest to cognitive research because it is highly expressed in the brain, particularly in the cognition-related brain regions. Recently, the functional role of PDE4B and PDE4D, two of the four PDE4 subtypes (PDE4A, B, C, and D), in behavior has begun to be identified; however, the role of PDE4A in the regulation of behavior is still unknown. The purpose of this study was to characterize the functional role of PDE4A in behavior. The role of PDE4A in behavior was evaluated through a battery of behavioral tests using PDE4A knockout (KO) mice; urine corticosterone levels were also measured. PDE4A KO mice exhibited improved memory in the step-through-passive-avoidance test. They also displayed anxiogenic-like behavior in elevated-plus maze, holeboard, light-dark transition, and novelty suppressed feeding tests. Consistent with the anxiety profile, PDE4A KO mice had elevated corticosterone levels compared with wild-type controls post-stress. Interestingly, PDE4A KO mice displayed no change in object recognition, Morris water maze, forced swim, tail suspension, and duration of anesthesia induced by co-administration of xylazine and ketamine (suggesting that PDE4A KO may not be emetic). These results suggest that PDE4A may be important in the regulation of emotional memory and anxiety-like behavior, but not emesis. PDE4A could possibly represent a novel therapeutic target in the future for anxiety or disorders affecting memory.

  17. Cyclic AMP-specific phosphodiesterase-4 as a target for the development of antidepressant drugs.

    Science.gov (United States)

    Zhang, Han-Ting

    2009-01-01

    Phosphodiesterase-4 (PDE4), one of eleven PDE enzyme families, specifically catalyzes hydrolysis of cyclic AMP (cAMP); it has four subtypes (PDE4A-D) with at least 25 splice variants. PDE4 plays a critical role in the control of intracellular cAMP concentrations. PDE4 inhibitors produce antidepressant actions in both animals and humans via enhancement of cAMP signaling in the brain. However, their clinical utility has been hampered by side effects, in particular nausea and emesis. While there is still a long way to go before PDE4 inhibitors with high therapeutic indices are available for treatment of depressive disorders, important advances have been made in the development of PDE4 inhibitors as antidepressants. First, limited, but significant studies point to PDE4D as the major PDE4 subtype responsible for antidepressant-like effects of PDE4 inhibitors, although the role of PDE4A cannot be excluded. Second, PDE4D may contribute to emesis, the major side effect of PDE4 inhibitors. For this reason, identification of roles of PDE4D splice variants in mediating antidepressant activity is particularly important. Recent studies using small interfering RNAs (siRNAs) have demonstrated the feasibility to identify cellular functions of individual PDE4 variants. Third, mixed inhibitors of PDE4 and PDE7 or PDE4 and serotonin reuptake have been developed and may be potential antidepressants with minimized side effects. Finally, relatively selective inhibitors of one or two PDE4 subtypes have been synthesized using structure- and scaffold-based design. This review also discusses the relationship between PDE4 and antidepressant activity based on structures, brain distributions, and pharmacological properties of PDE4 and its isoforms.

  18. Effect of Phosphodiesterase in Regulating the Activity of Lysosomes in the HeLa Cell Line.

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    Hong, Eun-Seon; Kim, Bit-Na; Kim, Yang-Hoon; Min, Jiho

    2017-02-28

    The transport of lysosomal enzymes into the lysosomes depends on the phosphorylation of their chains and the binding of the phosphorylated residues to mannose-6-phosphate receptors. The efficiency of separation depends more on the phosphodiesterases (PDEs) than on the activity of the phosphorylation of mannose residues and can be determined in vitro. PDEs play important roles in regulation of the activation of lysosomes. The expression of proteins was confirmed by western blotting. All PDE4 series protein expression was reduced in high concentrations of rolipram. As a result of observing the fluorescence intensity after rolipram treatment, the lysosomal enzyme was activated at low concentrations and suppressed at high concentrations. High concentrations of rolipram recovered the original function. Antimicrobial activity was not shown in either 10 or 100 µ concentrations of rolipram in treated HeLa cells in vitro. However, the higher anticancer activity at lower rolipram concentration was shown in lysosomal enzyme treated with 10 µ of rolipram. The anticancer activity was confirmed through cathepsin B and D assay. Tranfection allowed examination of the relationship between PDE4 and lysosomal activity in more detail. Protein expression was confirmed to be reduced. Fluorescence intensity showed decreased activity of lysosomes and ROS in cells transfected with the antisense sequences of PDE4 A, B, C, and D. PDE4A showed anticancer activity, whereas lysosome from cells transfected with the antisense sequences of PDE4 B, C, and D had decreased anticancer activity. These results showed the PDE4 A, B, C, and D are conjunctly related with lysosomal activity.

  19. Control of cytoplasmic and nuclear protein kinase A by phosphodiesterases and phosphatases in cardiac myocytes

    Science.gov (United States)

    Haj Slimane, Zeineb; Bedioune, Ibrahim; Lechêne, Patrick; Varin, Audrey; Lefebvre, Florence; Mateo, Philippe; Domergue-Dupont, Valérie; Dewenter, Matthias; Richter, Wito; Conti, Marco; El-Armouche, Ali; Zhang, Jin; Fischmeister, Rodolphe; Vandecasteele, Grégoire

    2014-01-01

    Aims The cAMP-dependent protein kinase (PKA) mediates β-adrenoceptor (β-AR) regulation of cardiac contraction and gene expression. Whereas PKA activity is well characterized in various subcellular compartments of adult cardiomyocytes, its regulation in the nucleus remains largely unknown. The aim of the present study was to compare the modalities of PKA regulation in the cytoplasm and nucleus of cardiomyocytes. Methods and results Cytoplasmic and nuclear cAMP and PKA activity were measured with targeted fluorescence resonance energy transfer probes in adult rat ventricular myocytes. β-AR stimulation with isoprenaline (Iso) led to fast cAMP elevation in both compartments, whereas PKA activity was fast in the cytoplasm but markedly slower in the nucleus. Iso was also more potent and efficient in activating cytoplasmic than nuclear PKA. Similar slow kinetics of nuclear PKA activation was observed upon adenylyl cyclase activation with L-858051 or phosphodiesterase (PDE) inhibition with 3-isobutyl-1-methylxantine. Consistently, pulse stimulation with Iso (15 s) maximally induced PKA and myosin-binding protein C phosphorylation in the cytoplasm, but marginally activated PKA and cAMP response element-binding protein phosphorylation in the nucleus. Inhibition of PDE4 or ablation of the Pde4d gene in mice prolonged cytoplasmic PKA activation and enhanced nuclear PKA responses. In the cytoplasm, phosphatase 1 (PP1) and 2A (PP2A) contributed to the termination of PKA responses, whereas only PP1 played a role in the nucleus. Conclusion Our study reveals a differential integration of cytoplasmic and nuclear PKA responses to β-AR stimulation in cardiac myocytes. This may have important implications in the physiological and pathological hypertrophic response to β-AR stimulation. PMID:24550350

  20. Evolution of multiple phosphodiesterase isoforms in stickleback involved in cAMP signal transduction pathway.

    Science.gov (United States)

    Sato, Yukuto; Hashiguchi, Yasuyuki; Nishida, Mutsumi

    2009-02-20

    Duplicate genes are considered to have evolved through the partitioning of ancestral functions among duplicates (subfunctionalization) and/or the acquisition of novel functions from a beneficial mutation (neofunctionalization). Additionally, an increase in gene dosage resulting from duplication may also confer an advantageous effect, as has been suggested for histone, tRNA, and rRNA genes. Currently, there is little understanding of the effect of increased gene dosage on subcellular networks like signal transduction pathways. Addressing this issue may provide further insights into the evolution by gene duplication. We analyzed the evolution of multiple stickleback phosphodiesterase (PDE, EC: 3.1.4.17) 1C genes involved in the cyclic nucleotide signaling pathway. Stickleback has 8-9 copies of this gene, whereas only one or two loci exist in other model vertebrates. Our phylogenetic and synteny analyses suggested that the multiple PDE1C genes in stickleback were generated by repeated duplications of >100-kbp chromosome segments. Sequence evolution analysis did not provide strong evidence for neofunctionalization in the coding sequences of stickleback PDE1C isoforms. On the other hand, gene expression analysis suggested that the derived isoforms acquired expression in new organs, implying their neofunctionalization in terms of expression patterns. In addition, at least seven isoforms of the stickleback PDE1C were co-expressed with olfactory-type G-proteins in the nose, suggesting that PDE1C dosage is increased in the stickleback olfactory transduction (OT) pathway. In silico simulations of OT implied that the increased PDE1C dosage extends the longevity of the depolarization signals of the olfactory receptor neuron. The predicted effect of the increase in PDE1C products on the OT pathway may play an important role in stickleback behavior and ecology. However, this possibility should be empirically examined. Our analyses imply that an increase in gene product sometimes

  1. Evolution of multiple phosphodiesterase isoforms in stickleback involved in cAMP signal transduction pathway

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    Nishida Mutsumi

    2009-02-01

    Full Text Available Abstract Background Duplicate genes are considered to have evolved through the partitioning of ancestral functions among duplicates (subfunctionalization and/or the acquisition of novel functions from a beneficial mutation (neofunctionalization. Additionally, an increase in gene dosage resulting from duplication may also confer an advantageous effect, as has been suggested for histone, tRNA, and rRNA genes. Currently, there is little understanding of the effect of increased gene dosage on subcellular networks like signal transduction pathways. Addressing this issue may provide further insights into the evolution by gene duplication. Results We analyzed the evolution of multiple stickleback phosphodiesterase (PDE, EC: 3.1.4.17 1C genes involved in the cyclic nucleotide signaling pathway. Stickleback has 8–9 copies of this gene, whereas only one or two loci exist in other model vertebrates. Our phylogenetic and synteny analyses suggested that the multiple PDE1C genes in stickleback were generated by repeated duplications of >100-kbp chromosome segments. Sequence evolution analysis did not provide strong evidence for neofunctionalization in the coding sequences of stickleback PDE1C isoforms. On the other hand, gene expression analysis suggested that the derived isoforms acquired expression in new organs, implying their neofunctionalization in terms of expression patterns. In addition, at least seven isoforms of the stickleback PDE1C were co-expressed with olfactory-type G-proteins in the nose, suggesting that PDE1C dosage is increased in the stickleback olfactory transduction (OT pathway. In silico simulations of OT implied that the increased PDE1C dosage extends the longevity of the depolarization signals of the olfactory receptor neuron. Conclusion The predicted effect of the increase in PDE1C products on the OT pathway may play an important role in stickleback behavior and ecology. However, this possibility should be empirically examined. Our

  2. Inhibition of chlorine-induced lung injury by the type 4 phosphodiesterase inhibitor rolipram

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Weiyuan; Chen, Jing; Schlueter, Connie F. [Department of Environmental and Occupational Health Sciences, School of Public Health and Information Sciences, University of Louisville, Louisville, KY (United States); Rando, Roy J. [Department of Environmental Health Sciences, School of Public Health and Tropical Medicine, Tulane University Health Sciences Center, New Orleans, LA (United States); Pathak, Yashwant V. [College of Pharmacy, University of South Florida, Tampa, FL (United States); Hoyle, Gary W., E-mail: Gary.Hoyle@louisville.edu [Department of Environmental and Occupational Health Sciences, School of Public Health and Information Sciences, University of Louisville, Louisville, KY (United States)

    2012-09-01

    Chlorine is a highly toxic respiratory irritant that when inhaled causes epithelial cell injury, alveolar-capillary barrier disruption, airway hyperreactivity, inflammation, and pulmonary edema. Chlorine is considered a chemical threat agent, and its release through accidental or intentional means has the potential to result in mass casualties from acute lung injury. The type 4 phosphodiesterase inhibitor rolipram was investigated as a rescue treatment for chlorine-induced lung injury. Rolipram inhibits degradation of the intracellular signaling molecule cyclic AMP. Potential beneficial effects of increased cyclic AMP levels include inhibition of pulmonary edema, inflammation, and airway hyperreactivity. Mice were exposed to chlorine (whole body exposure, 228–270 ppm for 1 h) and were treated with rolipram by intraperitoneal, intranasal, or intramuscular (either aqueous or nanoemulsion formulation) delivery starting 1 h after exposure. Rolipram administered intraperitoneally or intranasally inhibited chlorine-induced pulmonary edema. Minor or no effects were observed on lavage fluid IgM (indicative of plasma protein leakage), KC (Cxcl1, neutrophil chemoattractant), and neutrophils. All routes of administration inhibited chlorine-induced airway hyperreactivity assessed 1 day after exposure. The results of the study suggest that rolipram may be an effective rescue treatment for chlorine-induced lung injury and that both systemic and targeted administration to the respiratory tract were effective routes of delivery. -- Highlights: ► Chlorine causes lung injury when inhaled and is considered a chemical threat agent. ► Rolipram inhibited chlorine-induced pulmonary edema and airway hyperreactivity. ► Post-exposure rolipram treatments by both systemic and local delivery were effective. ► Rolipram shows promise as a rescue treatment for chlorine-induced lung injury.

  3. Phosphodiesterase-4 inhibition as a therapeutic approach to treat capillary leakage in systemic inflammation.

    Science.gov (United States)

    Schick, Martin Alexander; Wunder, Christian; Wollborn, Jakob; Roewer, Norbert; Waschke, Jens; Germer, Christoph-Thomas; Schlegel, Nicolas

    2012-06-01

    In sepsis and systemic inflammation, increased microvascular permeability and consecutive breakdown of microcirculatory flow significantly contribute to organ failure and death. Evidence points to a critical role of cAMP levels in endothelial cells to maintain capillary endothelial barrier properties in acute inflammation. However, approaches to verify this observation in systemic models are rare. Therefore we tested here whether systemic application of the phosphodiesterase-4-inhibitors (PD-4-Is) rolipram or roflumilast to increase endothelial cAMP was effective to attenuate capillary leakage and breakdown of microcirculatory flow in severe lipopolysaccharide (LPS)-induced systemic inflammation in rats. Measurements of cAMP in mesenteric microvessels demonstrated significant LPS-induced loss of cAMP levels which was blocked by application of rolipram. Increased endothelial cAMP by application of either PD-4-I rolipram or roflumilast led to stabilization of endothelial barrier properties as revealed by measurements of extravasated FITC-albumin in postcapillary mesenteric venules. Accordingly, microcirculatory flow in mesenteric venules was significantly increased following PD-4-I treatment and blood gas analyses indicated improved metabolism. Furthermore application of PD-4-I after manifestation of LPS-induced systemic inflammation and capillary leakage therapeutically stabilized endothelial barrier properties as revealed by significantly reduced volume resuscitation for haemodynamic stabilization. Accordingly microcirculation was significantly improved following treatment with PD-4-Is. Our results demonstrate that inflammation-derived loss of endothelial cAMP contributes to capillary leakage which was blocked by systemic PD-4-I treatment. Therefore these data suggest a highly clinically relevant and applicable approach to stabilize capillary leakage in sepsis and systemic inflammation.

  4. Cyclic AMP-specific phosphodiesterase, PDE8A1, is activated by protein kinase A-mediated phosphorylation

    OpenAIRE

    Brown, Kim M.; Lee, Louisa C.Y; Findlay, Jane E.; Day, Jonathan P.; Baillie, George S.

    2012-01-01

    The cyclic AMP-specific phosphodiesterase PDE8 has been shown to play a pivotal role in important processes such as steroidogenesis, T cell adhesion, regulation of heart beat and chemotaxis. However, no information exists on how the activity of this enzyme is regulated. We show that under elevated cAMP conditions, PKA acts to phosphorylate PDE8A on serine 359 and this action serves to enhance the activity of the enzyme. This is the first indication that PDE8 activity can be modulated by a kin...

  5. Phosphodiesterase-4 inhibition combined with isoniazid treatment of rabbits with pulmonary tuberculosis reduces macrophage activation and lung pathology.

    Science.gov (United States)

    Subbian, Selvakumar; Tsenova, Liana; O'Brien, Paul; Yang, Guibin; Koo, Mi-Sun; Peixoto, Blas; Fallows, Dorothy; Zeldis, Jerome B; Muller, George; Kaplan, Gilla

    2011-07-01

    Tuberculosis (TB) is responsible for significant morbidity and mortality worldwide. Even after successful microbiological cure of TB, many patients are left with residual pulmonary damage that can lead to chronic respiratory impairment and greater risk of additional TB episodes due to reinfection with Mycobacterium tuberculosis. Elevated levels of the proinflammatory cytokine tumor necrosis factor-α and several other markers of inflammation, together with expression of matrix metalloproteinases, have been associated with increased risk of pulmonary fibrosis, tissue damage, and poor treatment outcomes in TB patients. In this study, we used a rabbit model of pulmonary TB to evaluate the impact of adjunctive immune modulation, using a phosphodiesterase-4 inhibitor that dampens the innate immune response, on the outcome of treatment with the antibiotic isoniazid. Our data show that cotreatment of M. tuberculosis infected rabbits with the phosphodiesterase-4 inhibitor CC-3052 plus isoniazid significantly reduced the extent of immune pathogenesis, compared with antibiotic alone, as determined by histologic analysis of infected tissues and the expression of genes involved in inflammation, fibrosis, and wound healing in the lungs. Combined treatment with an antibiotic and CC-3052 not only lessened disease but also improved bacterial clearance from the lungs. These findings support the potential for adjunctive immune modulation to improve the treatment of pulmonary TB and reduce the risk of chronic respiratory impairment. Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  6. Mutation of the cyclic di-GMP phosphodiesterase gene in Burkholderia lata SK875 attenuates virulence and enhances biofilm formation.

    Science.gov (United States)

    Jung, Hae-In; Kim, Yun-Jung; Lee, Yun-Jung; Lee, Hee-Soo; Lee, Jung-Kee; Kim, Soo-Ki

    2017-10-01

    Burkholderia sp. is a gram-negative bacterium that commonly exists in the environment, and can cause diseases in plants, animals, and humans. Here, a transposon mutant library of a Burkholderia lata isolate from a pig with swine respiratory disease in Korea was screened for strains showing attenuated virulence in Caenorhabditis elegans. One such mutant was obtained, and the Tn5 insertion junction was mapped to rpfR, a gene encoding a cyclic di-GMP phosphodiesterase that functions as a receptor. Mutation of rpfR caused a reduction in growth on CPG agar and swimming motility as well as a rough colony morphology on Congo red agar. TLC analysis showed reduced AHL secretion, which was in agreement with the results from plate-based and bioluminescence assays. The mutant strain produced significantly more biofilm detected by crystal violet staining than the parent strain. SEM of the mutant strain clearly showed that the overproduced biofilm contained a filamentous structure. These results suggest that the cyclic di-GMP phosphodiesterase RpfR plays an important role in quorum sensing modulation of the bacterial virulence and biofilm formation.

  7. [Homozygous ectonucleotide pyrophosphatase/phosphodiesterase 1 variants in a girl with hypophosphatemic rickets and literature review].

    Science.gov (United States)

    Liu, Z Q; Chen, X B; Song, F Y; Gao, K; Qiu, M F; Qian, Y; Du, M

    2017-11-02

    Objective: To investigate the clinical features and genetic characteristics of patients with ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) gene variants. Method: The clinical data of a patient with ENPP1 homozygous variants from Capital Institute of Pediatrics was collected, the related literature was searched from China National Knowledge Infrastructure, Wanfang Data Knowledge Service Platform, National Center from Biotechnology Information and PubMed by using search term "ENPP1" , "hypophosphatemic rickets" . The literature retrieval was confined from 1980 to February 2017. The clinical manifestations, bone metabolism examinations, X-RAY and genotypes were reviewed. Result: Our patient was an 11 years old girl, with 7 years history of lower limb malformation. She showed significant valgus deformity of the knee (genu valgum). Metabolic examination revealed reduced level of plasma phosphate (0.86 mmol/L), a normal level of plasma calcium (2.30 mmol/L) and an elevated alkaline phosphatase level of 688 IU/L. The calcium-phosphorus product was 25.9. A homozygous nonsense variants of ENPP1 gene, c.783C>G (p.Tyr261X) in exon 7 was identified in the patient. Both parents were heterozygous carriers. Literature review identified 3 Chinese patients from one publication and 17 cases from twenty one publications around the world. None of the patients was found PHEX variants which is the most common variants among hypophosphatemic rickets patients. The disease onset age was 11 months to 10 years. Eight patients had short stature, five patients had the history of generalized arterial calcification of infancy. Four suffered from deafness, three showed localized calcifications of arteries, three patients manifested pseudoxanthoma elasticum and two suffered from ossification of posterior longitudinal ligament. Nine missense variants, six splicing variants and 4 nonsense variants were reported among these twenty patients. c.783C>G was found in two Chinese patients

  8. Interaction between leucine and phosphodiesterase 5 inhibition in modulating insulin sensitivity and lipid metabolism

    Directory of Open Access Journals (Sweden)

    Fu L

    2015-05-01

    Full Text Available Lizhi Fu,1 Fenfen Li,1 Antje Bruckbauer,2 Qiang Cao,1 Xin Cui,1 Rui Wu,1 Hang Shi,1 Bingzhong Xue,1 Michael B Zemel21Department of Biology, Center for Obesity Reversal, Georgia State University, Atlanta, GA, 2NuSirt Biopharma Inc., Nashville, TN, USA Purpose: Leucine activates SIRT1/AMP-activated protein kinase (AMPK signaling and markedly potentiates the effects of other sirtuin and AMPK activators on insulin signaling and lipid metabolism. Phosphodiesterase 5 inhibition increases nitric oxide–cGMP signaling, which in turn exhibits a positive feedback loop with both SIRT1 and AMPK, thus amplifying peroxisome proliferator-activated receptor γ co-activator α (PGC1α-mediated effects. Methods: We evaluated potential synergy between leucine and PDE5i on insulin sensitivity and lipid metabolism in vitro and in diet-induced obese (DIO mice. Results: Leucine (0.5 mM exhibited significant synergy with subtherapeutic doses (0.1–10 nM of PDE5-inhibitors (sildenafil and icariin on fat oxidation, nitric oxide production, and mitochondrial biogenesis in hepatocytes, adipocytes, and myotubes. Effects on insulin sensitivity, glycemic control, and lipid metabolism were then assessed in DIO-mice. DIO-mice exhibited fasting and postprandial hyperglycemia, insulin resistance, and hepatic steatosis, which were not affected by the addition of leucine (24 g/kg diet. However, the combination of leucine and a subtherapeutic dose of icariin (25 mg/kg diet for 6 weeks reduced fasting glucose (38%, P<0.002, insulin (37%, P<0.05, area under the glucose tolerance curve (20%, P<0.01, and fully restored glucose response to exogenous insulin challenge. The combination also inhibited hepatic lipogenesis, stimulated hepatic and muscle fatty acid oxidation, suppressed hepatic inflammation, and reversed high-fat diet-induced steatosis. Conclusion: These robust improvements in insulin sensitivity, glycemic control, and lipid metabolism indicate therapeutic potential for

  9. Co-possession of phosphodiesterase type-5 inhibitors (PDE5-I) with nitrates.

    Science.gov (United States)

    Chang, Li-Ling; Ma, Mark; Allmen, Heather von; Henderson, Scott C; Harper, Kristine; Hornbuckle, Kenneth

    2010-06-01

    Estimate the proportion of phosphodiesterase type-5 inhibitor (PDE5-I) patients who co-possess nitrates and compare the proportion of tadalafil patients dispensed nitrates to a matched control group. Secondarily, examine the percentage of co-possession of PDE5-Is and nitrates where the products were dispensed on the same day or written by the same prescriber. Male patients aged 18+ years filling PDE5-I prescriptions between December 2003 and March 2006 were identified using a U.S. longitudinal prescription database (IMS Health LRx). Similar patients not dispensed a PDE5-I during this period were matched to the tadalafil-dispensed cohort using a propensity score approach. Co-possession, as a proxy for concurrent use, was defined as an overlap in time on therapy for a PDE5-I and nitrate and was compared for the three PDE5-Is and for tadalafil to the matched control group. Among 601,063 tadalafil patients, 3.31% were dispensed a nitrate during the study period, compared to 6.18% in control patients (n = 601,063). When co-possessed prescriptions were defined by overlapping exposure periods, the proportion of PDE5-I patients with co-possessed nitrates ranged from 1.44% (tadalafil) to 1.72% (vardenafil) and 2.13% (sildenafil). Co-possession percentages of PDE5-I prescriptions were 0.83% for tadalafil and 1.07% for sildenafil and vardenafil. The majority (54.29%) of co-possessed PDE5-I and nitrate prescriptions had the nitrate dispensed prior to the PDE5-I prescription identified in the study cohort. Keeping in mind the limitations of observational studies, these results suggest that co-dispensing of nitrates and PDE5-Is is low. Compared to control patients, the proportion of nitrate co-possession was lowest for patients filling tadalafil. Tadalafil patients also had the lowest co-possessed proportion among the three PDE5-I cohorts. While the majority of co-possessed drug pairs were prescribed by different providers, the highest percentage of co-prescribing from the same

  10. Key role of phosphodiesterase 4A (PDE4A) in autophagy triggered by yessotoxin

    International Nuclear Information System (INIS)

    Fernández-Araujo, A.; Alfonso, A.; Vieytes, M.R.; Botana, L.M.

    2015-01-01

    Highlights: • YTX activates autophagic cell death after 48 h of treatment. • After 24 h of YTX incubation, the autophagic LC3B expression is increased. • High LC3B levels after 24 h can be related with extrinsic apoptosis activated by YTX. • PDEA4 plays a key role in the autophagy activation. - Abstract: Understanding the mechanism of action of the yessotoxin (YTX) is crucial since this drug has potential pharmacological effects in allergic processes, tumor proliferation and neurodegenerative diseases. It has been described that YTX activates apoptosis after 24 h of treatment, while after 48 h of incubation with the toxin a decrease in cell viability corresponding to cellular differentiation or non-apoptotic cell death was observed. In this paper, these processes were extensively studied by using the erythroleukemia K-562 cell line. On one hand, events of K-562 cell differentiation into erythrocytes after YTX treatment were studied using hemin as positive control of cell differentiation. Cell differentiation was studied through the cyclic nucleotide response element binding (phospho-CREB) and the transferrin receptor (TfR) expression. On the other hand, using rapamycin as positive control, autophagic hallmarks, as non-apoptotic cell death, were studied after toxin exposure. In this case, the mechanistic target of rapamycin (mTOR) and light chain 3B (LC3B) levels were measured to check autophagy activation. The results showed that cell differentiation was not occurring after 48 h of toxin incubation while at this time the autophagy was triggered. Furthermore after 24 h of toxin treatment none of these processes were activated. In addition, the role of the type 4A phosphodiesterase (PDE4A), the intracellular target of YTX, was checked. PDE4A-silencing experiments showed different regulation steps of PDE4A in the autophagic processes triggered either by traditional compounds or YTX. In summary, after 48 h YTX treatment PDE4A-dependent autophagy, as non

  11. Distinct patterns of constitutive phosphodiesterase activity in mouse sinoatrial node and atrial myocardium.

    Directory of Open Access Journals (Sweden)

    Rui Hua

    Full Text Available Phosphodiesterases (PDEs are critical regulators of cyclic nucleotides in the heart. In ventricular myocytes, the L-type Ca(2+ current (I(Ca,L is a major target of regulation by PDEs, particularly members of the PDE2, PDE3 and PDE4 families. Conversely, much less is known about the roles of PDE2, PDE3 and PDE4 in the regulation of action potential (AP properties and I(Ca,L in the sinoatrial node (SAN and the atrial myocardium, especially in mice. Thus, the purpose of our study was to measure the effects of global PDE inhibition with Isobutyl-1-methylxanthine (IBMX and selective inhibitors of PDE2, PDE3 and PDE4 on AP properties in isolated mouse SAN and right atrial myocytes. We also measured the effects of these inhibitors on I(Ca,L in SAN and atrial myocytes in comparison to ventricular myocytes. Our data demonstrate that IBMX markedly increases spontaneous AP frequency in SAN myocytes and AP duration in atrial myocytes. Spontaneous AP firing in SAN myocytes was also increased by the PDE2 inhibitor erythro-9-[2-hydroxy-3-nonyl] adenine (EHNA, the PDE3 inhibitor milrinone (Mil and the PDE4 inhibitor rolipram (Rol. In contrast, atrial AP duration was increased by EHNA and Rol, but not by Mil. IBMX also potently, and similarly, increased I(Ca,L in SAN, atrial and ventricular myocytes; however, important differences emerged in terms of which inhibitors could modulate I(Ca,L in each myocyte type. Consistent with our AP measurements, EHNA, Mil and Rol each increased I(Ca,L in SAN myocytes. Also, EHNA and Rol, but not Mil, increased atrial I(Ca,L. In complete contrast, no selective PDE inhibitors increased I(Ca,L in ventricular myocytes when given alone. Thus, our data show that the effects of selective PDE2, PDE3 and PDE4 inhibitors are distinct in the different regions of the myocardium indicating important differences in how each PDE family constitutively regulates ion channel function in the SAN, atrial and ventricular myocardium.

  12. Atrazine acts as an endocrine disrupter by inhibiting cAMP-specific phosphodiesterase-4

    International Nuclear Information System (INIS)

    Kucka, Marek; Pogrmic-Majkic, Kristina; Fa, Svetlana; Stojilkovic, Stanko S.; Kovacevic, Radmila

    2012-01-01

    Atrazine, one of the most commonly used herbicides worldwide, acts as an endocrine disruptor, but the mechanism of its action has not been characterized. In this study, we show that atrazine rapidly increases cAMP levels in cultured rat pituitary and testicular Leydig cells in a concentration-dependent manner, but less effectively than 3-isobutyl-1-methylxanthine, a competitive non-specific inhibitor of phosphodiesterases (PDEs). In forskolin (an activator of adenylyl cyclase)- and probenecid (an inhibitor of cyclic nucleotide transporters)-treated cells, but not in 3-isobutyl-1-methylxanthine-treated cells, atrazine further increased cAMP levels, indicating that inhibition of PDEs accounts for accumulation of cAMP. In contrast to cAMP, atrazine did not alter cGMP levels, further indicating that it inhibits cAMP-specific PDEs. Atrazine-induced changes in cAMP levels were sufficient to stimulate prolactin release in pituitary cells and androgen production in Leydig cells, indicating that it acts as an endocrine disrupter both in cells that secrete by exocytosis of prestored hormones and in cells that secrete by de novo hormone synthesis. Rolipram abolished the stimulatory effect of atrazine on cAMP release in both cell types, suggesting that it acts as an inhibitor of PDE4s, isoforms whose mRNA transcripts dominate in pituitary and Leydig cells together with mRNA for PDE8A. In contrast, immortalized lacto-somatotrophs showed low expression of these mRNA transcripts and several fold higher cAMP levels compared to normal pituitary cells, and atrazine was unable to further increase cAMP levels. These results indicate that atrazine acts as a general endocrine disrupter by inhibiting cAMP-specific PDE4s. -- Highlights: ► Atrazine stimulates cAMP accumulation in pituitary and Leydig cells. ► Atrazine also stimulates PRL and androgens secretion. ► Stimulatory effects of atrazine were abolished in cells with IBMX-inhibited PDEs. ► Atrazine specificity toward c

  13. Psychotherapy and phosphodiesterase-5 inhibitor in early rehabilitation after radical prostatectomy: a prospective randomised controlled trial.

    Science.gov (United States)

    Naccarato, A M E P; Reis, L O; Ferreira, U; Denardi, F

    2016-12-01

    The aim of this study was to evaluate the impact of group psychotherapy and the use of a phosphodiesterase-5 inhibitor (PDE-5i) in the early rehabilitation stage of patients with prostate cancer undergoing radical prostatectomy (RP). Fifty-six patients undergoing RP for prostate cancer were randomised into four groups, and 53 completed the protocol: Group 1 - control (n = 11), Group 2 - group psychotherapy (n = 16), Group 3 - lodenafil 80 mg/one tablet per week (n = 12) and Group 4 - group psychotherapy + lodenafil 80 mg/one tablet per week (n = 14). The groups were individually evaluated for erectile function (IIEF-5) and quality of life - QoL (SF-36) weekly, with two meetings held a week apart before the RP and 12 weekly meetings after surgery. The ages ranged from 39 to 76 years, average 61.84. There were no significant medication side effects. Only Group 4 showed improvement in intimacy with a partner and satisfaction with their sex life (P = 0.045 and P = 0.013 respectively), and with no significant worsening of the IIEF-5 (P = 0.250) reported. All groups showed worsening in the final result of the role limitations caused by physical problems (P = 0.009) and role limitations caused by emotional problems (P = 0.002) of the SF-36, but Group 4 had a significantly higher score for the role limitations caused by physical problems (P = 0.009) than the other groups. In conclusion, precocious integral treatment involving group psychotherapy and PDE-5i before and after RP led to less deterioration of erectile function and other domains related to physical aspects (SF-36), with improvement in intimacy with their partner and satisfaction in their sex life, being superior to single treatments. © 2016 Blackwell Verlag GmbH.

  14. Phosphodiesterase 4 inhibition as a potential new therapeutic target in obese women with polycystic ovary syndrome.

    Science.gov (United States)

    Jensterle, Mojca; Kocjan, Tomaz; Janez, Andrej

    2014-08-01

    Phosphodiesterase (PDE) enzymes, including members of PDE4, have been investigated in the regulation of endocrine and reproductive functions of ovaries. In addition, selective inhibition of PDE4 enzyme has recently been implicated in the regulation of metabolism with positive effects on glucose homeostasis and weight reduction. The aim of this study was to evaluate whether the PDE4 inhibitor roflumilast affects body weight and hormonal and metabolic status in obese women with polycystic ovary syndrome (PCOS). Design/Participants/Main Outcome Measures: A 12-week prospective randomized open-label study was conducted with 36 obese women with PCOS diagnosed by the National Eunice Kennedy Shriver Institute of Child Health and Human Development criteria that had been pretreated with metformin (MET). They were randomized to MET 1000 mg twice a day or combined treatment (COM) with MET 1000 mg twice a day and roflumilast 500 μg every day. The primary outcome was change in anthropometric measures of obesity. Thirty-one patients (aged 33.8 ± 7.4 y, twice a day 36.4 ± 5.1 kg/m(2), mean ± SD) completed the study: 16 on MET and 15 on COM. Subjects treated with COM lost on average 4.2 ± 2.8 kg compared with a 0.9 ± 2.5 kg weight gain in the MET group (P = .025). Body mass index decreased for 1.6 ± 1.1 kg/m(2) in COM arm compared with increase for 0.9 ± 2.4 kg/m(2) in the MET arm (P = .046). Visceral adipose tissue area as assessed by dual-energy x-ray absorptiometry decreased from 136.7 ± 37.8 to 121.2 ± 36.2 cm(2) in the COM arm compared with an increase from 155.3 ± 61.9 to 166.7 ± 67.2 cm(2) in the MET arm (P = .02). From baseline to study end, both treatment interventions resulted in a significant reduction of androstenedione (P = .013), free T (P = .002), and homeostasis model assessment for insulin resistance score (P = .027) and a significant increase in SHBG (P = .024), although the between-treatment differences of the changes have not been statistically

  15. THE PRESENCE OF 5 CYCLIC-NUCLEOTIDE PHOSPHODIESTERASE ISOENZYME ACTIVITIES IN BOVINE TRACHEAL SMOOTH-MUSCLE AND THE FUNCTIONAL-EFFECTS OF SELECTIVE INHIBITORS

    NARCIS (Netherlands)

    VANAMSTERDAM, RGM; DEBOER, J; TENBERGE, RE; NICHOLSON, CD; ZAAGSMA, J

    1991-01-01

    1 The profile of cyclic nucleotide phosphodiesterase (PDE) isoenzymes and the relaxant effects of isoenzyme selective inhibitors were examined in bovine tracheal smooth muscle. The compounds examined were the non-selective inhibitor 3-isobutyl-1-methylxanthine (IBMX), zaprinast (PDE V selective),

  16. Catalytic enhancement of the heme-based oxygen-sensing phosphodiesterase EcDOS by hydrogen sulfide is caused by changes in heme coordination structure

    Czech Academy of Sciences Publication Activity Database

    Yang, F.; Fojtíková, V.; Man, Petr; Stráňava, M.; Martínková, M.; Du, Y.; Huang, D.; Shimizu, T.

    2015-01-01

    Roč. 28, č. 4 (2015), s. 637-652 ISSN 0966-0844 Grant - others:OPPC(XE) CZ.2.16/3.1.00/24023 Institutional support: RVO:61388971 Keywords : Heme * O-2 sensor * Phosphodiesterase Subject RIV: CE - Biochemistry Impact factor: 2.134, year: 2015

  17. Mechanistic insights into the role of prenyl-binding protein PrBP/δ in membrane dissociation of phosphodiesterase 6

    KAUST Repository

    Qureshi, Bilal M.; Schmidt, Andrea; Behrmann, Elmar; Bü rger, Jö rg; Mielke, Thorsten; Spahn, Christian M. T.; Heck, Martin; Scheerer, Patrick

    2018-01-01

    Isoprenylated proteins are associated with membranes and their inter-compartmental distribution is regulated by solubilization factors, which incorporate lipid moieties in hydrophobic cavities and thereby facilitate free diffusion during trafficking. Here we report the crystal structure of a solubilization factor, the prenyl-binding protein (PrBP/δ), at 1.81 Å resolution in its ligand-free apo-form. Apo-PrBP/δ harbors a preshaped, deep hydrophobic cavity, capacitating apo-PrBP/δ to readily bind its prenylated cargo. To investigate the molecular mechanism of cargo solubilization we analyzed the PrBP/δ-induced membrane dissociation of rod photoreceptor phosphodiesterase (PDE6). The results suggest that PrBP/δ exclusively interacts with the soluble fraction of PDE6. Depletion of soluble species in turn leads to dissociation of membrane-bound PDE6, as both are in equilibrium. This

  18. Benzoquinones and terphenyl compounds as phosphodiesterase-4B inhibitors from a fungus of the order Chaetothyriales (MSX 47445).

    Science.gov (United States)

    El-Elimat, Tamam; Figueroa, Mario; Raja, Huzefa A; Graf, Tyler N; Adcock, Audrey F; Kroll, David J; Day, Cynthia S; Wani, Mansukh C; Pearce, Cedric J; Oberlies, Nicholas H

    2013-03-22

    Three bioactive compounds were isolated from an organic extract of an ascomycete fungus of the order Chaetothyriales (MSX 47445) using bioactivity-directed fractionation as part of a search for anticancer leads from filamentous fungi. Of these, two were benzoquinones [betulinan A (1) and betulinan C (3)], and the third was a terphenyl compound, BTH-II0204-207:A (2). The structures were elucidated using a set of spectroscopic and spectrometric techniques; the structure of the new compound (3) was confirmed via single-crystal X-ray diffraction. Compounds 1-3 were evaluated for cytotoxicity against a human cancer cell panel, for antimicrobial activity against Staphylococcus aureus and Candida albicans, and for phosphodiesterase (PDE4B2) inhibitory activities. The putative binding mode of 1-3 with PDE4B2 was examined using a validated docking protocol, and the binding and enzyme inhibitory activities were correlated.

  19. Mechanistic insights into the role of prenyl-binding protein PrBP/δ in membrane dissociation of phosphodiesterase 6

    KAUST Repository

    Qureshi, Bilal M.

    2018-01-02

    Isoprenylated proteins are associated with membranes and their inter-compartmental distribution is regulated by solubilization factors, which incorporate lipid moieties in hydrophobic cavities and thereby facilitate free diffusion during trafficking. Here we report the crystal structure of a solubilization factor, the prenyl-binding protein (PrBP/δ), at 1.81 Å resolution in its ligand-free apo-form. Apo-PrBP/δ harbors a preshaped, deep hydrophobic cavity, capacitating apo-PrBP/δ to readily bind its prenylated cargo. To investigate the molecular mechanism of cargo solubilization we analyzed the PrBP/δ-induced membrane dissociation of rod photoreceptor phosphodiesterase (PDE6). The results suggest that PrBP/δ exclusively interacts with the soluble fraction of PDE6. Depletion of soluble species in turn leads to dissociation of membrane-bound PDE6, as both are in equilibrium. This

  20. Psiguajadials A-K: Unusual Psidium Meroterpenoids as Phosphodiesterase-4 Inhibitors from the Leaves of Psidium guajava.

    Science.gov (United States)

    Tang, Gui-Hua; Dong, Zhen; Guo, Yan-Qiong; Cheng, Zhong-Bin; Zhou, Chu-Jun; Yin, Sheng

    2017-04-21

    Bioassay-guided fractionation of the ethanolic extract of the leaves of Psidium guajava led to the isolation of 11 new Psidium meroterpenoids, psiguajadials A-K (1-11), along with 17 known ones (12-28). Their structures and absolute configurations were elucidated by spectroscopic methods and comparison of experimental and calculated ECD. Compounds 1 and 2 represent two unprecedented skeletons of 3,5-diformyl-benzyl phloroglucinol-coupled sesquiterpenoid, while 3 is the first example of Psidium meroterpenoids coupling via an oxepane ring. Putative biosynthetic pathways towards 1 and 2 are proposed. Compounds 1-13 and 16-26 exhibited moderate inhibitory activities against phosphodiesterase-4 (PDE4), a drug target for asthma and chronic obstructive pulmonary disease, with IC 50 values in the range of 1.34-7.26 μM.

  1. Novel Radioligands for Cyclic Nucleotide Phosphodiesterase Imaging with Positron Emission Tomography: An Update on Developments Since 2012

    Directory of Open Access Journals (Sweden)

    Susann Schröder

    2016-05-01

    Full Text Available Cyclic nucleotide phosphodiesterases (PDEs are a class of intracellular enzymes that inactivate the secondary messenger molecules, cyclic adenosine monophosphate (cAMP and cyclic guanosine monophosphate (cGMP. Thus, PDEs regulate the signaling cascades mediated by these cyclic nucleotides and affect fundamental intracellular processes. Pharmacological inhibition of PDE activity is a promising strategy for treatment of several diseases. However, the role of the different PDEs in related pathologies is not completely clarified yet. PDE-specific radioligands enable non-invasive visualization and quantification of these enzymes by positron emission tomography (PET in vivo and provide an important translational tool for elucidation of the relationship between altered expression of PDEs and pathophysiological effects as well as (pre-clinical evaluation of novel PDE inhibitors developed as therapeutics. Herein we present an overview of novel PDE radioligands for PET published since 2012.

  2. Antenatal phosphodiesterase 4 inhibition restores postnatal growth and pulmonary development in a model of chorioamnionitis in rabbits.

    Science.gov (United States)

    Homer, L; Launay, E; Joram, N; Jacqueline, C; Jarreau, P-H; Caillon, J; Moyon, T; Branger, B; Potel, G; Roze, J C; Méhats, C; Gras-Leguen, C

    2012-03-01

    Chorioamnionitis is implicated in the pathophysiology of bronchopulmonary disease, and the associated inflammatory response is responsible for adverse effects on alveolar development. The aim of this work was to analyze the effects of a phosphodiesterase 4 (PDE4)-selective inhibitor, rolipram (a modulator of the inflammatory response), in an experimental model of chorioamnionitis on pulmonary development and on the processes of infection and inflammation. Rabbit mothers were assigned to four groups: 1) saline serum inoculation (controls); 2) Escherichia coli intrauterine inoculation (C+); 3) rolipram infusion (R+); and 4) E. coli inoculation + rolipram infusion (C+R+). High rates of morbility and mortality were noticed in mothers and pups (5 of 13 pregnant rabbits in groups with rolipram). Alveolar development, inflammation, and infection were analyzed in pups at day 0 and day 5. At day 0, in the context of chorioamnionitis, rolipram significantly decreased birth weight (p demise and growth retardation.

  3. Cigarette Smoke-Induced Emphysema and Pulmonary Hypertension Can Be Prevented by Phosphodiesterase 4 and 5 Inhibition in Mice

    Science.gov (United States)

    Pichl, Alexandra; Bednorz, Mariola; Ghofrani, Hossein Ardeschir; Schermuly, Ralph Theo; Seeger, Werner; Grimminger, Friedrich; Weissmann, Norbert

    2015-01-01

    Rationale Chronic obstructive pulmonary disease (COPD) is a widespread disease, with no curative therapies available. Recent findings suggest a key role of NO and sGC-cGMP signaling for the pathogenesis of the disease. Previous data suggest a downregulation/inactivation of the cGMP producing soluble guanylate cyclase, and sGC stimulation prevented cigarette smoke-induced emphysema and pulmonary hypertension (PH) in mice. We thus aimed to investigate if the inhibition of the cGMP degrading phosphodiesterase (PDE)5 has similar effects. Results were compared to the effects of a PDE 4 inhibitor (cAMP elevating) and a combination of both. Methods C57BL6/J mice were chronically exposed to cigarette smoke and in parallel either treated with Tadalafil (PDE5 inhibitor), Piclamilast (PDE4 inhibitor) or both. Functional measurements (lung compliance, hemodynamics) and structural investigations (alveolar and vascular morphometry) as well as the heart ratio were determined after 6 months of tobacco smoke exposure. In addition, the number of alveolar macrophages in the respective lungs was counted. Results Preventive treatment with Tadalafil, Piclamilast or a combination of both almost completely prevented the development of emphysema, the increase in lung compliance, tidal volume, structural remodeling of the lung vasculature, right ventricular systolic pressure, and right ventricular hypertrophy induced by cigarette smoke exposure. Single, but not combination treatment prevented or reduced smoke-induced increase in alveolar macrophages. Conclusion Cigarette smoke-induced emphysema and PH could be prevented by inhibition of the phosphodiesterases 4 and 5 in mice. PMID:26058042

  4. Sildenafil, a selective phosphodiesterase type 5 inhibitor, enhances memory reconsolidation of an inhibitory avoidance task in mice.

    Science.gov (United States)

    Boccia, M M; Blake, M G; Krawczyk, M C; Baratti, C M

    2011-07-07

    Intracellular levels of the second messengers cAMP and cGMP are maintained through a balance between production, carried out by adenyl cyclase (AC) and guanylyl cyclase (GC), and degradation, carried out by phosphodiesterases (PDEs). Recently, PDEs have gained increased attention as potential new targets for cognition enhancement, with particular reference to phosphodiesterase type 5 (PDE5A). It is accepted that once consolidation is completed memory becomes permanent, but it has also been suggested that reactivation (memory retrieval) of the original memory makes it sensitive to the same treatments that affect memory consolidation when given after training. This new period of sensitivity coined the term reconsolidation. Sildenafil (1, 3, and 10mg/kg, ip), a cGMP-PDE5 inhibitor, facilitated retention performance of a one-trial step-through inhibitory avoidance task, when administered to CF-1 male mice immediately after retrieval. The effects of sildenafil (1mg/kg, ip) were time-dependent, long-lasting and inversely correlated with memory age. The administration of sildenafil (1mg/kg, ip) 30 min prior to the 2nd retention test did not affect retention of mice given post-retrieval injections of either vehicle or sildenafil (1mg/kg, ip). Finally, an enhancement of retention was also observed in CF-1 female mice receiving sildenafil (1mg/kg, ip) immediately, but not 180 min after retrieval. In the present paper we reported for the first time that systemic administration of sildenafil after memory reactivation enhances retention performance of the original learning. Our results indirectly point out cGMP, a component of the NO/cGMP/PKG pathway, as a necessary factor for memory reconsolidation. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Effects of rolipram, a phosphodiesterase 4 inhibitor, in combination with imipramine on depressive behavior, CRE-binding activity and BDNF level in learned helplessness rats.

    Science.gov (United States)

    Itoh, Tetsuji; Tokumura, Miwa; Abe, Kohji

    2004-09-13

    The brain cAMP regulating system and its downstream elements play a pivotal role in the therapeutic effects of antidepressants. We previously reported the increase in activities of phosphodiesterase 4, a major phosphodiesterase isozyme hydrolyzing cAMP, in the frontal cortex and hippocampus of learned helplessness rats, an animal model for depression. The present study was undertaken to examine the combination of effects of rolipram, a phosphodiesterase 4 inhibitor, with imipramine, a typical tricyclic antidepressant, on depressive behavior in learned helplessness rats. Concurrently, cAMP-response element (CRE)-binding activity and brain-derived neurotrophic factor (BDNF) levels related to the therapeutic effects of antidepressants were determined. Repeated administration of imipramine (1.25-10 mg/kg, i.p.) or rolipram (1.25 mg/kg, i.p.) reduced the number of escape failures in learned helplessness rats. Imipramine could not completely ameliorate the escape behavior to a level similar to that of non-stressed rats even at 10 mg/kg. However, repeated coadministration of rolipram with imipramine (1.25 and 2.5 mg/kg, respectively) almost completely eliminated the escape failures in learned helplessness rats. The reduction of CRE-binding activities and BDNF levels in the frontal cortex or hippocampus in learned helplessness rats were ameliorated by treatment with imipramine or rolipram alone. CRE-binding activities and/or BDNF levels of the frontal cortex and hippocampus were significantly increased by treatment with a combination of rolipram and imipramine compared to those in imipramine-treated rats. These results indicated that coadministration of phosphodiesterase type 4 inhibitors with antidepressants may be more effective for depression therapy and suggest that elevation of the cAMP signal transduction pathway is involved in the antidepressive effects.

  6. The phosphodiesterase 5 inhibitor sildenafil has no effect on cerebral blood flow or blood velocity, but nevertheless induces headache in healthy subjects

    DEFF Research Database (Denmark)

    Kruuse, Christina; Thomsen, Lars Lykke; Jacobsen, Torsten Bjørn

    2002-01-01

    Cyclic nucleotides are important hemodynamic regulators in many tissues. Glyceryl trinitrate markedly dilates large cerebral arteries and increases cGMP. Here, the authors study the effect of sildenafil, a selective inhibitor of cGMP-hydrolyzing phosphodiesterase 5 on cerebral hemodynamics...... of cerebral arterial dilatation, sildenafil caused significantly more headache than placebo. The present results show that sildenafil 100 mg does not dilate cerebral or extracerebral arteries but nevertheless causes headache, which may be attributed to nonvascular mechanisms....

  7. [Application of precursor ion scanning method in rapid screening of illegally added phosphodiesterase-5 inhibitors and their unknown derivatives in Chinese traditional patent medicines and health foods].

    Science.gov (United States)

    Sun, Jing; Cao, Ling; Feng, Youlong; Tan, Li

    2014-11-01

    The compounds with similar structure often have similar pharmacological activities. So it is a trend for illegal addition that new derivatives of effective drugs are synthesized to avoid the statutory test. This bring challenges to crack down on illegal addition behavior, however, modified derivatives usually have similar product ions, which allow for precursor ion scanning. In this work, precursor ion scanning mode of a triple quadrupole mass spectrometer was first applied to screen illegally added drugs in complex matrix such as Chinese traditional patent medicines and healthy foods. Phosphodiesterase-5 inhibitors were used as experimental examples. Through the analysis of the structure and mass spectrum characteristics of the compounds, phosphodiesterase-5 inhibitors were classified, and their common product ions were screened by full scan of product ions of typical compounds. Then high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method with precursor ion scanning mode was established based on the optimization of MS parameters. The effect of mass parameters and the choice of fragment ions were also studied. The method was applied to determine actual samples and further refined. The results demonstrated that this method can meet the need of rapid screening of unknown derivatives of phosphodiesterase-5 inhibitors in complex matrix, and prevent unknown derivatives undetected. This method shows advantages in sensitivity, specificity and efficiency, and is worth to be further investigated.

  8. The effect of selective phosphodiesterase inhibitors, alone and in combination, on a murine model of allergic asthma

    Directory of Open Access Journals (Sweden)

    Galbraith Deirdre

    2004-05-01

    Full Text Available Abstract Background The anti-inflammatory effects of the selective phosphodiesterase (PDE inhibitors cilostazol (PDE 3, RO 20-1724 (PDE 4 and sildenafil (PDE 5 were examined in a murine model of allergic asthma. These compounds were used alone and in combination to determine any potential synergism, with dexamethasone included as a positive control. Methods Control and ovalbumin sensitised Balb/C mice were administered orally with each of the possible combinations of drugs at a dose of 3 mg/Kg for 10 days. Results When used alone, RO 20-1724 significantly reduced eosinophil influx into lungs and lowered tumour necrosis factor-α, interleukin-4 and interleukin-5 levels in the bronchoalveolar lavage fluid when compared to untreated mice. Treatment with cilostazol or sildenafil did not significantly inhibit any markers of inflammation measured. Combining any of these PDE inhibitors produced no additive or synergistic effects. Indeed, the anti-inflammatory effects of RO 20-1724 were attenuated by co-administration of either cilostazol or sildenafil. Conclusions These results suggest that concurrent treatment with a PDE 3 and/or PDE 5 inhibitor will reduce the anti-inflammatory effectiveness of a PDE 4 inhibitor.

  9. Milrinone, a phosphodiesterase III inhibitor, prevents reduction of jugular bulb saturation during rewarming from hypothermic cardiopulmonary bypass.

    Science.gov (United States)

    Iritakenishi, T; Hayashi, Y; Yamanaka, H; Kamibayashi, T; Ueda, K; Mashimo, T

    2012-01-01

    Inadequate cerebral oxygen balance during cardiopulmonary bypass may cause neuropsychological dysfunction. Milrinone, a phosphodiesterase III inhibitor, augments cerebral blood flow by direct vasodilatation. We conducted a prospective, randomized study in patients undergoing cardiac surgery with cardiopulmonary bypass to clarify the clinical efficacy of milrinone in the imbalance of cerebral oxygen supply and demand during the rewarming period of cardiopulmonary bypass. This is a prospective, randomized and placebo-controlled study. After anesthesia, a 5.5 F fiberoptic oximeter catheter was inserted into the right jugular bulb retrogradely for monitoring the jugular venous oxyhemoglobin saturation (SjO(2)). Patients were randomly assigned to two groups, one receiving a continuous infusion of milrinone, 0.5 µg/kg/min during hypothermic cardiopulmonary bypass, and the other receiving saline as control. Milrinone significantly prevented the reduction of the jugular venous oxyhemoglobin saturation at 10 minutes from the start of rewarming compared with the control group, but did not do so from 10 to 20 minutes after rewarming. Milrinone suppresses the reduction of SjO(2) and improves the balance of cerebral oxygen supply and demand during the early rewarming period of hypothermic cardiopulmonary bypass.

  10. LC-ESI-MS/MS analysis of phosphodiesterase-5 inhibitors and their analogues in foods and dietary supplements in Korea.

    Science.gov (United States)

    Jeong, Ji Hye; Lee, Ji Hyun; Kim, Hyung Joo; Park, Hyoung Joon; Hwang, In Sun; Han, Kyoung Moon; Yoon, Chang-Yong; Cho, Sooyeul; Kim, Woo Seong

    2016-01-01

    A number of 188 food and dietary supplement samples were collected from 2009 to the first half of 2013 in Korean online and offline stores. A method to identify phosphodiesterase-5 (PDE-5) inhibitors and their analogues using liquid chromatography-electrospray ionisation-mass spectrometry/mass spectrometry (LC-ESI-MS/MS) was validated. Limit of detection and limit of quantitation of liquid-type and solid-type negative samples ranged from 0.05 to 3.33 ng/mL or ng/g and from 0.15 to 10.00 ng/mL or ng/g, respectively. Recoveries ranged from 83% to 112%. Nineteen PDE-5 inhibitors and their analogues were detected, with tadalafil group compounds being the most frequently observed (53.0%), followed by the sildenafil group (42.5%). Tadalafil concentrations ranged from 0.08 to 138.69 mg/g. Compounds were most frequently detected in capsules (in 40 of 80 adulterated samples). To protect public health and food safety, appropriate monitoring of PDE-5 inhibitors and their analogues in foods and dietary supplements is recommended.

  11. Human biodistribution and dosimetry of {sup 18}F-JNJ42259152, a radioligand for phosphodiesterase 10A imaging

    Energy Technology Data Exchange (ETDEWEB)

    Laere, Koen van [University Hospital Leuven and KU Leuven, Division of Nuclear Medicine, Leuven (Belgium); University Hospital Leuven - Gasthuisberg, Division of Nuclear Medicine, Leuven (Belgium); Ahmad, Rawaha U.; Hudyana, Hendra; Koole, Michel [University Hospital Leuven and KU Leuven, Division of Nuclear Medicine, Leuven (Belgium); Celen, Sofie; Bormans, Guy [KU Leuven, Laboratory for Radiopharmacy, Leuven (Belgium); Dubois, Kristof; Schmidt, Mark E. [Division of Janssen Pharmaceuticals NV, Janssen Research and Development, Beerse (Belgium)

    2013-02-15

    Phosphodiesterase 10A (PDE10A) is a cAMP/cGMP-hydrolysing enzyme with a central role in striatal signalling and implicated in neuropsychiatric disorders such as Huntington's disease, Parkinson's disease, schizophrenia and addiction. We have developed a novel PDE10A PET ligand, {sup 18}F-JNJ42259152, and describe here its human dynamic biodistribution, safety and dosimetry. Six male subjects (age range 23-67 years) underwent ten dynamic whole-body PET/CT scans over 6 h after bolus injection of 175.5 {+-} 9.4 MBq {sup 18}F-JNJ42259152. Source organs were delineated on PET/CT and individual organ doses and effective dose were determined using the OLINDA software. F-JNJ42259152 was readily taken up by the brain and showed exclusive retention in the brain, especially in the striatum with good washout starting after 20 min. The tracer was cleared through both the hepatobiliary and the urinary routes. No defluorination was observed. Organ absorbed doses were largest for the gallbladder (239 {mu}Sv/MBq) and upper large intestine (138 {mu}Sv/MBq). The mean effective dose was 24.9 {+-} 4.1 {mu}Sv/MBq. No adverse events were encountered. In humans, {sup 18}F-JNJ42259152 has an appropriate distribution, brain kinetics and safety. The estimated effective dose was within WHO class IIb with low interindividual variability. Therefore, the tracer is suitable for further kinetic evaluation in humans. (orig.)

  12. Hesperetin, a Selective Phosphodiesterase 4 Inhibitor, Effectively Suppresses Ovalbumin-Induced Airway Hyperresponsiveness without Influencing Xylazine/Ketamine-Induced Anesthesia

    Directory of Open Access Journals (Sweden)

    Chung-Hung Shih

    2012-01-01

    Full Text Available Hesperetin, a selective phosphodiesterase (PDE4 inhibitor, is present in the traditional Chinese medicine, “Chen Pi.” Therefore, we were interested in investigating its effects on ovalbumin- (OVA- induced airway hyperresponsiveness, and clarifying its rationale for ameliorating asthma and chronic obstructive pulmonary disease (COPD. Hesperetin was revealed to have a therapeutic (PDE4H/PDE4L ratio of >11. Hesperetin (10 ~ 30 μmol/kg, intraperitoneally (i.p. dose-dependently and significantly attenuated the airway hyperresponsiveness induced by methacholine. It also significantly suppressed the increases in total inflammatory cells, macrophages, lymphocytes, neutrophils, and eosinophils, and levels of cytokines, including interleukin (IL-2, IL-4, IL-5, interferon-γ, and tumor necrosis factor-α in bronchoalveolar lavage fluid (BALF. It dose-dependently and significantly suppressed total and OVA-specific immunoglobulin E levels in the BALF and serum. However, hesperetin did not influence xylazine/ketamine-induced anesthesia, suggesting that hesperetin has few or no emetic effects. In conclusion, the rationales for ameliorating allergic asthma and COPD by hesperetin are anti-inflammation, immunoregulation, and bronchodilation.

  13. The phosphodiesterase 3 inhibitor ORG 9935 inhibits oocyte maturation in the naturally selected dominant follicle in rhesus macaques.

    Science.gov (United States)

    Jensen, Jeffrey T; Zelinski, Mary B; Stanley, Jessica E; Fanton, John W; Stouffer, Richard L

    2008-04-01

    The study was conducted to determine whether the phosphodiesterase (PDE) 3 inhibitor ORG 9935 prevents the resumption of meiosis in primate oocytes during natural menstrual cycles. Regularly cycling adult female macaques (n=8) were followed during the follicular phase and then started on a 2-day treatment regimen of human recombinant gonadotropins to control the timing of ovulation. Monkeys received no further treatment (controls) or ORG 9935. Oocytes were recovered by laparoscopic follicle aspiration 27 h after an ovulatory stimulus, cultured in vitro in the absence of inhibitor and inseminated. The primary outcome was the meiotic stage of the oocyte. In six ORG 9935 cycles, five of the recovered oocytes were germinal vesicle (GV)-intact, and one exhibited GV breakdown (GVBD). In contrast, all three oocytes that recovered during control cycles were GVBD (pORG 9935-treated oocytes underwent fertilization compared with 2/3 (67%) from controls. These results demonstrate that ORG 9935 blocks resumption of meiosis in the naturally selected dominant follicle in primates and suggest that PDE3 inhibitors have potential clinical use as contraceptives in women.

  14. Genetic variants of phosphodiesterase 4D gene are associated with an enhanced risk for ischemic stroke in young Chinese population.

    Science.gov (United States)

    He, Ying; Yang, Dong Zhi; Yu, Hui; Li, Man Yu; Feng, Qing Chuan; Zheng, Hong

    2013-01-01

    Previous studies have shown that the phosphodiesterase 4D (PDE4D) gene is a susceptibility gene for ischemic stroke (IS) primarily in elder populations. However, few studies have reported the role of the PDE4D gene polymorphisms in a young cohort. To investigate the association between the PDE4D gene polymorphisms and young-onset IS in Chinese population. A total of 186 young patients (18-45 years) with IS and 232 matched control subjects were recruited. Two SNPs (rs918592 and rs2910829) in PDE4D gene were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Odds ratio and 95% confidence intervals (95% CI) were calculated to test the association between the genetic factors and IS. The rs918592A/A genotype frequency and A allele frequency, rs2910829 CT/TT genotype frequency and T allele frequency of young IS group were significantly higher than those of the control group ( P young patients than that in the controls (OR =4.047, 95% CI: 3.521-4.652). Hap (A-C) and Hap (G-C) were associated with decreased risk of IS (OR =0.640, 95% CI: 0.452-0.906; OR =0.675, 95% CI: 0.466-0.978, respectively). Our findings suggest that the rs918592 and rs2910829 polymorphisms and haplotypes of PDE4D gene are significantly associated with IS in Chinese young population.

  15. Patient preference and satisfaction in erectile dysfunction therapy: a comparison of the three phosphodiesterase-5 inhibitors sildenafil, vardenafil and tadalafil

    Directory of Open Access Journals (Sweden)

    Amr Abdel Raheem

    2009-04-01

    Full Text Available Amr Abdel Raheem1, Philip Kell21St. Peter’s Andrology Department, The Institute of Urology, London, and Cairo University, Egypt; 2St. Peter’s Andrology Department, The Institute of Urology, London, UKAbstract: Erectile dysfunction (ED is a problem that may affect up to 52% of men between the ages of 40 and 70. It can be distressing because of its negative effect on self-esteem, quality of life, and interpersonal relationships. Oral phosphodiesterase-5 inhibitors (PDE5 inhibitors are now the first choice of treatment in ED. The availability of three (sildenafil citrate, tadalafil, and vardenafil well tolerated and effective oral PDE5 inhibitors gives treatment options for men with ED. Although the mechanism of action is the same for the three drugs, they differ in their pharmacokinetics. Several preference studies were conducted between the three PDE5 inhibitors but they were not free from bias. Because of the lack of overwhelming reliable data showing that one PDE5 inhibitor is superior to another, current opinion is that the individual patient should have the opportunity to test all three drugs and then select the one that best suits him and his partner.Keywords: erectile dysfunction, PDE5 inhibitors, patient preference

  16. Genetic deletion and pharmacological inhibition of phosphodiesterase 10A protects mice from diet-induced obesity and insulin resistance.

    Science.gov (United States)

    Nawrocki, Andrea R; Rodriguez, Carlos G; Toolan, Dawn M; Price, Olga; Henry, Melanie; Forrest, Gail; Szeto, Daphne; Keohane, Carol Ann; Pan, Yie; Smith, Karen M; Raheem, Izzat T; Cox, Christopher D; Hwa, Joyce; Renger, John J; Smith, Sean M

    2014-01-01

    Phosphodiesterase 10A (PDE10A) is a novel therapeutic target for the treatment of schizophrenia. Here we report a novel role of PDE10A in the regulation of caloric intake and energy homeostasis. PDE10A-deficient mice are resistant to diet-induced obesity (DIO) and associated metabolic disturbances. Inhibition of weight gain is due to hypophagia after mice are fed a highly palatable diet rich in fats and sugar but not a standard diet. PDE10A deficiency produces a decrease in caloric intake without affecting meal frequency, daytime versus nighttime feeding behavior, or locomotor activity. We tested THPP-6, a small molecule PDE10A inhibitor, in DIO mice. THPP-6 treatment resulted in decreased food intake, body weight loss, and reduced adiposity at doses that produced antipsychotic efficacy in behavioral models. We show that PDE10A inhibition increased whole-body energy expenditure in DIO mice fed a Western-style diet, achieving weight loss and reducing adiposity beyond the extent seen with food restriction alone. Therefore, chronic THPP-6 treatment conferred improved insulin sensitivity and reversed hyperinsulinemia. These data demonstrate that PDE10A inhibition represents a novel antipsychotic target that may have additional metabolic benefits over current medications for schizophrenia by suppressing food intake, alleviating weight gain, and reducing the risk for the development of diabetes.

  17. Prenylated flavonoids as potent phosphodiesterase-4 inhibitors from Morus alba: Isolation, modification, and structure-activity relationship study.

    Science.gov (United States)

    Guo, Yan-Qiong; Tang, Gui-Hua; Lou, Lan-Lan; Li, Wei; Zhang, Bei; Liu, Bo; Yin, Sheng

    2018-01-20

    The bioassay-guided phytochemical study of a traditional Chinese medicine Morus alba led to the isolation of 18 prenylated flavonoids (1-18), of which (±)-cyclomorusin (1/2), a pair of enantiomers, and 14-methoxy-dihydromorusin (3) are the new ones. Subsequent structural modification of the selected components by methylation, esterification, hydrogenation, and oxidative cyclization led to 14 more derivatives (19-32). The small library was screened for its inhibition against phosphodiesterase-4 (PDE4), which is a drug target for the treatment of asthma and chronic obstructive pulmonary disease (COPD). Among them, nine compounds (1-5, 8, 10, 16, and 17) exhibited remarkable activities with IC 50 values ranging from 0.0054 to 0.40 μM, being more active than the positive control rolipram (IC 50  = 0.62 μM). (+)-Cyclomorusin (1), the most active natural PDE4 inhibitor reported so far, also showed a high selectivity across other PDE members with the selective fold greater than 55. The SAR study revealed that the presence of prenyls at C-3 and/or C-8, 2H-pyran ring D, and the phenolic hydroxyl groups were important to the activity, which was further supported by the recognition mechanism study of the inhibitors with PDE4 by using molecular modeling. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  18. Imaging cAMP-specific phosphodiesterase-4 in human brain with R-[11C]rolipram and positron emission tomography

    International Nuclear Information System (INIS)

    DaSilva, Jean N.; Lourenco, Celia M.; Meyer, Jeffrey H.; Houle, Sylvain; Hussey, Douglas; Potter, William Z.

    2002-01-01

    Evidence of disruptions in cAMP-mediated signaling in several neuropsychiatric disorders has led to the development of R-[ 11 C]rolipram for imaging phosphodiesterase-4 (PDE4) enzymes with positron emission tomography (PET). The high-affinity PDE4 inhibitor rolipram was previously reported to have an antidepressant effect in humans. PDE4 is abundant in the brain, and it hydrolyzes cAMP produced following stimulation of various neurotransmitter systems. PDE4 is regulated by intracellular cAMP levels. This paper presents the first PET study of R-[ 11 C]rolipram in living human brain. Consistent with the wide distribution of PDE4, high radioactivity retention was observed in all regions representing the gray matter. Rapid metabolism was observed, and kinetic analysis demonstrated that the data fit in a two-tissue compartment model. R-[ 11 C]Rolipram is thus suitable for imaging PDE4 and possibly cAMP signal transduction in the living human brain with PET. (orig.)

  19. The Phosphodiesterase 4 Inhibitor Roflumilast Protects against Cigarette Smoke Extract-Induced Mitophagy-Dependent Cell Death in Epithelial Cells.

    Science.gov (United States)

    Kyung, Sun Young; Kim, Yu Jin; Son, Eun Suk; Jeong, Sung Hwan; Park, Jeong Woong

    2018-04-01

    Recent studies show that mitophagy, the autophagy-dependent turnover of mitochondria, mediates pulmonary epithelial cell death in response to cigarette smoke extract (CSE) exposure and contributes to the development of emphysema in vivo during chronic cigarette smoke (CS) exposure, although the underlying mechanisms remain unclear. In this study, we investigated the role of mitophagy in the regulation of CSE-exposed lung bronchial epithelial cell (Beas-2B) death. We also investigated the role of a phosphodiesterase 4 inhibitor, roflumilast, in CSE-induced mitophagy-dependent cell death. Our results demonstrated that CSE induces mitophagy in Beas-2B cells through mitochondrial dysfunction and increased the expression levels of the mitophagy regulator protein, PTEN-induced putative kinase-1 (PINK1), and the mitochondrial fission protein, dynamin-1-like protein (DRP1). CSE-induced epithelial cell death was significantly increased in Beas-2B cells exposed to CSE but was decreased by small interfering RNA-dependent knockdown of DRP1. Treatment with roflumilast in Beas-2B cells inhibited CSE-induced mitochondrial dysfunction and mitophagy by inhibiting the expression of phospho-DRP1 and -PINK1. Roflumilast protected against cell death and increased cell viability, as determined by the lactate dehydrogenase release test and the MTT assay, respectively, in Beas-2B cells exposed to CSE. These findings suggest that roflumilast plays a protective role in CS-induced mitophagy-dependent cell death. Copyright©2018. The Korean Academy of Tuberculosis and Respiratory Diseases.

  20. Catecholic amides as potential selective phosphodiesterase 4D inhibitors: Design, synthesis, pharmacological evaluation and structure-activity relationships.

    Science.gov (United States)

    Zhou, Zhong-Zhen; Ge, Bing-Chen; Chen, Yu-Fang; Shi, Xiu-Dong; Yang, Xue-Mei; Xu, Jiang-Ping

    2015-11-15

    In this study, a series of catechol-based amides (8a-n) with different amide linkers linking the catecholic moiety to the terminal phenyl ring was designed and synthesized as potent phosphodiesterase (PDE) 4D inhibitors. The inhibitory activities of these compounds were evaluated against the core catalytic domains of human PDE4 (PDE4CAT), full-length PDE4B1 and PDE4D7 enzymes, and other PDE family members. The results indicated the majority of compounds 8a-n displayed moderate to good inhibitory activities against PDE4CAT. Among these compounds, compound 8 j with a short amide linker (-CONHCH2-) displayed comparable PDE4CAT inhibitory activity (IC50=410 nM) with rolipram. More interestingly, compound 8 g, a potent and selective PDE4D inhibitor (IC50=94 nM), exhibited a 10-fold selectivity over the PDE4B subtypes and an over 1000-fold selectivity against other PDE family members. Docking simulations suggested that 8 g forms three extra H-bonds with the N-H of residue Asn487 and two water molecules. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Changes in calmodulin concentration and cyclic 3',5'-nucleotide phosphodiesterase activity in skeletal muscle of hyper- and hypothyroid rats.

    Science.gov (United States)

    Mano, T; Iwase, K; Yoshimochi, I; Sawai, Y; Oda, N; Nishida, Y; Mokuno, T; Kotake, M; Nakai, A; Hayakawa, N

    1995-08-01

    Hyper- and hypothyroid states occasionally induce skeletal muscle dysfunction i.e. periodic paralysis and thyroid myopathy. The etiology of these diseases remains unclear, but several findings suggest that the catecholamine-beta-receptor-cAMP system or other messenger systems are disturbed in these diseases. In this context, we evaluated changes in the cyclic 3',5'-nucleotide metabolic enzyme, cyclic 3',5'-nucleotide phosphodiesterase (PDE) and calmodulin concentrations in skeletal muscles of hyper- and hypothyroid rats. Activities of cyclic AMP-PDE were low in skeletal muscle both from hyper- and hypothyroid rats, and calmodulin concentration was high in hyperthyroid and low in hypothyroid rats, as compared with normal rats. DE-52 column chromatographic analysis showed that the cGMP hydrolytic activity in peak I and the cAMP hydrolytic activity in peak II were decreased in hypothyroid rats, whereas cAMP hydrolytic activity in peak III was unchanged. The cAMP hydrolytic activity in peak III was decreased in hyperthyroid rats, but the activities in peaks I and II were unchanged. These findings indicate that cAMP and calmodulin may have some role in skeletal muscle function in the hyperthyroid state, and that cAMP and calmodulin-dependent metabolism may be suppressed in the hypothyroid state.

  2. Novel Therapeutic Targets for Phosphodiesterase 5 Inhibitors: current state-of-the-art on systemic arterial hypertension and atherosclerosis.

    Science.gov (United States)

    Vasquez, Elisardo C; Gava, Agata L; Graceli, Jones B; Balarini, Camille M; Campagnaro, Bianca P; Pereira, Thiago Melo C; Meyrelles, Silvana S

    2016-01-01

    The usefulness of selective inhibitors of phosphodiesterase 5 (PDE5) is well known, first for the treatment of male erectile dysfunction and more recently for pulmonary hypertension. The discovery that PDE5 is present in the systemic artery endothelium and smooth muscle cells led investigators to test the extra sexual effects of sildenafil, the first and most investigated PDE5 inhibitor, in diseases affecting the systemic arteries. Cumulative data from experimental and clinical studies have revealed beneficial effects of sildenafil on systemic arterial hypertension and its target organs, such as the heart, kidneys and vasculature. An important effect of sildenafil is reduction of hypertension and improvement of endothelial function in experimental models of hypertension and hypertensive subjects. Interestingly, in angiotensin-dependent hypertension, its beneficial effects on endothelial and kidney dysfunctions seem to at least in part be caused by its ability to decrease the levels of angiotensin II and increase angiotensin 1-7, in addition to improving nitric oxide bioavailability and diminishing reactive oxygen species. Another remarkable finding on the effects of sildenafil comes from studies in apolipoprotein E knockout mice, a model of atherosclerosis that closely resembles human atherosclerotic disease. In this review, we focus on the promising beneficial effects of sildenafil for treating systemic high blood pressure, especially resistant hypertension, and the endothelial dysfunction that is present in hypertension and atherosclerosis.

  3. Synthesis, radiolabeling and in vivo evaluation of [{sup 11}C]RAL-01, a potential phosphodiesterase 5 radioligand

    Energy Technology Data Exchange (ETDEWEB)

    Jakobsen, Steen [PET Centre, Aarhus University Hospitals, 8000 Aarhus (Denmark)]. E-mail: steen@pet.auh.dk; Kodahl, Gitte Munkebo [PET Centre, Aarhus University Hospitals, 8000 Aarhus (Denmark); Olsen, Aage Kristian [PET Centre, Aarhus University Hospitals, 8000 Aarhus (Denmark); Cumming, Paul [PET Centre, Aarhus University Hospitals, 8000 Aarhus (Denmark); Centre for Functionally Integrative Neuroscience, Aarhus University, Aarhus (Denmark)

    2006-07-15

    Very few tracers are available for imaging studies of second messenger systems. We developed a radiosynthesis for the phosphodiesterase (PDE) 5 inhibitor [{sup 11}C]RAL-01. Whole body distribution studies using positron emission tomography (PET) revealed a time-dependant passage through the liver and accumulation of radioactivity in the bile of the Landrace pig. Displaceable binding was readily discerned in the myocardium, and traces of binding were seen in pulmonary tissue, consistent with the use of this class of drug in the treatment of pulmonary hypertension and heart failure. [{sup 11}C]RAL-01 readily entered the brain and obtained an equilibrium distribution volume of 4-5 ml g{sup -1}. Mean parametric images suggested the presence of a small displaceable binding component, but this binding was not significant in the present group of three pigs. Thus, [{sup 11}C]RAL-01 shows considerable promise for PET studies of biliary elimination and of PDE5 binding in the cardiovascular system. However, analogues of higher affinity may be required for investigations of central nervous system binding sites.

  4. Functional phosphodiesterase 11A mutations may modify the risk of familial and bilateral testicular germ cell tumors

    Science.gov (United States)

    Horvath, Anelia; Korde, Larissa; Greene, Mark H.; Libe, Rosella; Osorio, Paulo; Faucz, Fabio Rueda; Raffin-Sanson, Marie Laure; Tsang, Kit Man; Drori-Herishanu, Limor; Patronas, Yianna; Remmers, Elaine F; Nikita, Maria-Elena; Moran, Jason; Greene, Joseph; Nesterova, Maria; Merino, Maria; Bertherat, Jerome; Stratakis, Constantine A.

    2009-01-01

    Inactivating germline mutations in phosphodiesterase 11A (PDE11A) have been implicated in adrenal tumor susceptibility. PDE11A is highly-expressed in endocrine steroidogenic tissues, especially the testis, and mice with inactivated Pde11a exhibit male infertility, a known testicular germ cell tumor (TGCT) risk factor. We sequenced the PDE11A gene-coding region in 95 patients with TGCT from 64 unrelated kindreds. We identified 8 non-synonymous substitutions in 20 patients from 15 families: four (R52T; F258Y; G291R; V820M) were newly-recognized, three (R804H; R867G; M878V) were functional variants previously implicated in adrenal tumor predisposition, and one (Y727C) was a known polymorphism. We compared the frequency of these variants in our patients to unrelated controls that had been screened and found negative for any endocrine diseases: only the two previously-reported variants, R804H and R867G, known to be frequent in general population, were detected in these controls. The frequency of all PDE11A-gene variants (combined) was significantly higher among patients with TGCT (P=0.0002), present in 19% of the families of our cohort. Most variants were detected in the general population, but functional studies showed that all these mutations reduced PDE activity, and that PDE11A protein expression was decreased (or absent) in TGCT samples from carriers. This is the first demonstration of a PDE gene’s involvement in TGCT, although the cAMP signaling pathway has been investigated extensively in other reproductive organs and their diseases. In conclusion, we report that PDE11A-inactivating sequence variants may modify the risk of familial and bilateral TGCT. PMID:19549888

  5. Adenoviral short hairpin RNA therapy targeting phosphodiesterase 5a relieves cardiac remodeling and dysfunction following myocardial infarction

    Science.gov (United States)

    Li, Longhu; Haider, Husnain Kh.; Wang, Linlin; Lu, Gang

    2012-01-01

    We previously showed that treatment with tadalafil, a long-acting phosphodiesterase-5a (PDE5a) inhibitor, effectively prevented adverse left ventricular (LV) remodeling of the infarcted heart. We hypothesized that short-hairpin RNA (shRNA) therapy targeting PDE5a would simulate the effects of pharmacological intervention for treatment of postinfarction LV remodeling and dysfunction. Experimental model of myocardial infarction was developed in female mice by permanent ligation of left coronary artery. Immediately after that, an adenoviral vector encoding for shRNA sequence targeting PDE5a (Ad-shPDE5a) was injected intramyocardially, which specifically inhibited PDE5a in the heart. Four weeks later, Ad-shPDE5a treated mice showed significant mitigation of the left ventricle (LV) dilatation and dysfunction as indicated by smaller LV cavity and more preserved ejection fraction and fractional shortening. Infarction size and fibrosis were significantly reduced in Ad-shPDE5a-treated mice. Additionally, more salvaged cardiomyocytes, significantly reduced collagen contents, and higher blood vessel density were observed in Ad-shPDE5a-treated mice. The cytoprotective effects of Ad-shPDE5a were demonstrated in vitro in Ad-shPDE5a transfected cardiomyocytes cultured under oxygen glucose deprivation. Among downstream mediators of PDE5a signaling, cyclic GMP (cGMP) and cGMP-dependent protein kinase G (PKG) were activated with concomitant reduction in caspase-3 activity. However, no significant change in PKA and cAMP activities were observed in Ad-shPDE5a-treated hearts. Inhibition with shRNA improved cardiac remodeling and dysfunction by reducing infarction size and cardiac fibrosis and increased cGMP and PKG activity. These findings suggest that PDE5 inhibition with Ad-shPDE5a is a novel approach for treatment of myocardial infarction. PMID:22447941

  6. Phosphodiesterase-4 inhibition alters gene expression and improves isoniazid-mediated clearance of Mycobacterium tuberculosis in rabbit lungs.

    Directory of Open Access Journals (Sweden)

    Selvakumar Subbian

    2011-09-01

    Full Text Available Tuberculosis (TB treatment is hampered by the long duration of antibiotic therapy required to achieve cure. This indolent response has been partly attributed to the ability of subpopulations of less metabolically active Mycobacterium tuberculosis (Mtb to withstand killing by current anti-TB drugs. We have used immune modulation with a phosphodiesterase-4 (PDE4 inhibitor, CC-3052, that reduces tumor necrosis factor alpha (TNF-α production by increasing intracellular cAMP in macrophages, to examine the crosstalk between host and pathogen in rabbits with pulmonary TB during treatment with isoniazid (INH. Based on DNA microarray, changes in host gene expression during CC-3052 treatment of Mtb infected rabbits support a link between PDE4 inhibition and specific down-regulation of the innate immune response. The overall pattern of host gene expression in the lungs of infected rabbits treated with CC-3052, compared to untreated rabbits, was similar to that described in vitro in resting Mtb infected macrophages, suggesting suboptimal macrophage activation. These alterations in host immunity were associated with corresponding down-regulation of a number of Mtb genes that have been associated with a metabolic shift towards dormancy. Moreover, treatment with CC-3052 and INH resulted in reduced expression of those genes associated with the bacterial response to INH. Importantly, CC-3052 treatment of infected rabbits was associated with reduced ability of Mtb to withstand INH killing, shown by improved bacillary clearance, from the lungs of co-treated animals compared to rabbits treated with INH alone. The results of our study suggest that changes in Mtb gene expression, in response to changes in the host immune response, can alter the responsiveness of the bacteria to antimicrobial agents. These findings provide a basis for exploring the potential use of adjunctive immune modulation with PDE4 inhibitors to enhance the efficacy of existing anti-TB treatment.

  7. Identification of the gamma subunit-interacting residues on photoreceptor cGMP phosphodiesterase, PDE6alpha '.

    Science.gov (United States)

    Granovsky, A E; Artemyev, N O

    2000-12-29

    Photoreceptor cGMP phosphodiesterase (PDE6) is the effector enzyme in the G protein-mediated visual transduction cascade. In the dark, the activity of PDE6 is shut off by the inhibitory gamma subunit (Pgamma). Chimeric proteins between cone PDE6alpha' and cGMP-binding and cGMP-specific PDE (PDE5) have been constructed and expressed in Sf9 cells to study the mechanism of inhibition of PDE6 catalytic activity by Pgamma. Substitution of the segment PDE5-(773-820) by the corresponding PDE6alpha'-(737-784) sequence in the wild-type PDE5 or in a PDE5/PDE6alpha' chimera containing the catalytic domain of PDE5 results in chimeric enzymes capable of inhibitory interaction with Pgamma. The catalytic properties of the chimeric PDEs remained similar to those of PDE5. Ala-scanning mutational analysis of the Pgamma-binding region, PDE6alpha'-(750-760), revealed PDE6alpha' residues essential for the interaction. The M758A mutation markedly impaired and the Q752A mutation moderately impaired the inhibition of chimeric PDE by Pgamma. The analysis of the catalytic properties of mutant PDEs and a model of the PDE6 catalytic domain suggest that residues Met(758) and Gln(752) directly bind Pgamma. A model of the PDE6 catalytic site shows that PDE6alpha'-(750-760) forms a loop at the entrance to the cGMP-binding pocket. Binding of Pgamma to Met(758) would effectively block access of cGMP to the catalytic cavity, providing a structural basis for the mechanism of PDE6 inhibition.

  8. Effects of phosphodiesterase inhibitors on atrial dynamics induced by C-type natriuretic peptide in isolated beating rabbit atria

    International Nuclear Information System (INIS)

    Ding Dazhi; Cui Xun; Jin Xiunan; Lan Ying; Liu Liping; Hong Lan

    2010-01-01

    Objective: To investigate the effects of phosphodiesterase inhibitors (PDEI) on atrial dynamics induced by C-type natriuretic peptide (CNP) and the contents of cyclic nucleotide (cAMP, cGMP) in isolated beating rabbit atria. Methods: After the rabbits had been anesthetized, the hearts were removed rapidly. The left auricles were isolated and fixed on the atrial perfusion system. The atrial stroke volume and the pulse pressure were observed by CNP with or without PDEIs pretreatment. The contents of cAMP and cGMP were measured by radioimmunoassay. Results: (1)Compared with control cycle group, CNP (30.0 nmol · L -1 ) obviously decreased the atrial stroke volume and pulse pressure (P 0.05). (2)Compared with control cycle group, IBMX(1000.0 nmol · L -1 ), a non-selective inhibitor of PDE, significantly increased the atrial stroke volume, pulse pressure, cAMP and cGMP contents (P -1 ) plus CNP (30.0 nmol · L -1 )group and IBMX group (P>0.05). (3)Compared with control cycle group, EHNA(30.0 nmol · L -1 ), an inhibitor of PDE2, obviously decreased the atrial stroke volume and pulse pressure (P 0.05). EHNA(30.0 nmol · L -1 ) plus CNP (30.0 nmol · L -1 ) showed similar roles with EHNA only. (4)Compared with control cycle group, milrinone (1.0 nmol · L -1 ), an inhibitor of PDE3, significantly increased the content of cAMP (P 0.05). CNP (30.0 nmol · L -1 ) obviously decreased the atrial stroke volume and pulse pressure (P 0.05). Conclusion: CNP can inhibit atrial dynamics by increasing the content of cGMP, the different inhibitors of PDEs play different roles in the CNP-induced inhibition of atrial dynamics in isolated beating rabbit atria. (authors)

  9. cGMP-phosphodiesterase inhibition enhances photic responses and synchronization of the biological circadian clock in rodents.

    Directory of Open Access Journals (Sweden)

    Santiago A Plano

    Full Text Available The master circadian clock in mammals is located in the hypothalamic suprachiasmatic nuclei (SCN and is synchronized by several environmental stimuli, mainly the light-dark (LD cycle. Light pulses in the late subjective night induce phase advances in locomotor circadian rhythms and the expression of clock genes (such as Per1-2. The mechanism responsible for light-induced phase advances involves the activation of guanylyl cyclase (GC, cGMP and its related protein kinase (PKG. Pharmacological manipulation of cGMP by phosphodiesterase (PDE inhibition (e.g., sildenafil increases low-intensity light-induced circadian responses, which could reflect the ability of the cGMP-dependent pathway to directly affect the photic sensitivity of the master circadian clock within the SCN. Indeed, sildenafil is also able to increase the phase-shifting effect of saturating (1200 lux light pulses leading to phase advances of about 9 hours, as well as in C57 a mouse strain that shows reduced phase advances. In addition, sildenafil was effective in both male and female hamsters, as well as after oral administration. Other PDE inhibitors (such as vardenafil and tadalafil also increased light-induced phase advances of locomotor activity rhythms and accelerated reentrainment after a phase advance in the LD cycle. Pharmacological inhibition of the main downstream target of cGMP, PKG, blocked light-induced expression of Per1. Our results indicate that the cGMP-dependent pathway can directly modulate the light-induced expression of clock-genes within the SCN and the magnitude of light-induced phase advances of overt rhythms, and provide promising tools to design treatments for human circadian disruptions.

  10. Efficacy of phosphodiesterase type 5 inhibitors for the treatment of distal ureteral calculi: A systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Montes Cardona

    2017-03-01

    Full Text Available Purpose: To determine the efficacy of phosphodiesterase type 5 inhibitors (PDE5i as medical expulsive therapy (MET for the treatment of distal ureteral calculi. Materials and Methods: A search strategy was conducted in the MEDLINE, CENTRAL, and Embase databases. Searches were also conducted in other databases and unpublished literature. Clinical trials were included without language restrictions. The risk of bias was evaluated with the Cochrane Collaboration’s tool. An analysis of random effects due to statistical heterogeneity was conducted. The primary outcome was the expulsion rate of the distal ureteral calculus in 28 days. The secondary outcomes were the time to expulsion, side effects of treatment, and amount (mg of nonopioid analgesia. The measure of the effect was the risk difference (RD with a 95% confidence interval (CI. The planned interventions were PDE5i vs. placebo, tadalafil vs. placebo, and tadalafil vs. tamsulosin. Results: Four articles were included in the qualitative and quantitative analysis. Records of 580 patients were found among the four studies. A low risk of bias was shown for the majority of the study items. The calculi expulsion rate had an RD of 0.26 (95% CI, 0.15–0.37 and a less prolonged expulsion as a secondary outcome with a mean difference of -4.39 days (95% CI, -6.69 to -2.09 in favor of PDE5i compared with the placebo. No significant difference was found for these outcomes when comparing tadalafil with tamsulosin. Conclusions: Compared with a placebo, PDE5i could be effective as MET for the treatment of distal ureter calculi.

  11. Exercise training improves erectile dysfunction (ED) in patients with metabolic syndrome on phosphodiesterase-5 (PDE-5) inhibitors.

    Science.gov (United States)

    Maresca, Luigi; D'Agostino, Mariantonietta; Castaldo, Luigi; Vitelli, Alessandra; Mancini, Maria; Torella, Giorgio; Lucci, Rosa; Albano, Giovanna; Del Forno, Domenico; Ferro, Matteo; Altieri, Vincenzo; Giallauria, Francesco; Vigorito, Carlo

    2013-12-01

    Erectile dysfunction (ED) affects about 50% of males aged 40-70 years old. ED shares with atherosclerotic disease several common risk factors; therefore, it may be considered a surrogate marker of atherosclerosis. Since phosphodiesterase-5 inhibitors are well known pharmacologic agents capable of significant improvement in ED, we designed this study to evaluate whether exercise training is of added value in patients with ED who are already on PDE-5 inhibitors. We recruited 20 male patients affected by ED with metabolic syndrome. At baseline, all patients underwent Cardio-Pulmonary Exercise Testing (CPET) and the International Index of Erectile Function (IIEF) test. After the initial evaluation, patients were subdivided into two groups: tadalafil group (group T, n = 10), who were maintained only on tadalafil therapy, and a tadalafil/exercise training group (T/E group, n = 10) who continued tadalafil but in addition underwent a2-month structured exercise training program. Basal anthropometric characteristics of study population showed no significant differences. Although both-groups showed at 2 months an improvement of the IIEF score, this was more evident in the T/E group (T group: 11.2 vs 14.2, P = 0.02; T/E group: 10.8 vs 20.1, P exercise (VO(2peak)) only in the T/E group patients (T group: 13.63 +/- 2.03 vs 14.24 +/- 2.98 mL/kg/min; P = 0.521; T/E group: 13.41 +/- 2.97 vs 16.58 +/- 3.17 mL/kg/min; P = 0.006). A significant correlation was found between the changes in VO(2peak) and the modifications in IIEF score (r = 0.575; P = 0.001). Exercise training in ED patients treated with PDE-5 inhibitors is of added value since further improves ED, as evaluated by IIEF score, and increases functional capacity.

  12. The effect of resveratrol on beta amyloid-induced memory impairment involves inhibition of phosphodiesterase-4 related signaling.

    Science.gov (United States)

    Wang, Gang; Chen, Ling; Pan, Xiaoyu; Chen, Jiechun; Wang, Liqun; Wang, Weijie; Cheng, Ruochuan; Wu, Fan; Feng, Xiaoqing; Yu, Yingcong; Zhang, Han-Ting; O'Donnell, James M; Xu, Ying

    2016-04-05

    Resveratrol, a natural polyphenol found in red wine, has wide spectrum of pharmacological properties including antioxidative and antiaging activities. Beta amyloid peptides (Aβ) are known to involve cognitive impairment, neuroinflammatory and apoptotic processes in Alzheimer's disease (AD). Activation of cAMP and/or cGMP activities can improve memory performance and decrease the neuroinflammation and apoptosis. However, it remains unknown whether the memory enhancing effect of resveratrol on AD associated cognitive disorders is related to the inhibition of phosphodiesterase 4 (PDE4) subtypes and subsequent increases in intracellular cAMP and/or cGMP activities. This study investigated the effect of resveratrol on Aβ1-42-induced cognitive impairment and the participation of PDE4 subtypes related cAMP or cGMP signaling. Mice microinfused with Aβ1-42 into bilateral CA1 subregions displayed learning and memory impairment, as evidenced by reduced memory acquisition and retrieval in the water maze and retention in the passive avoidance tasks; it was also significant that neuroinflammatory and pro-apoptotic factors were increased in Aβ1-42-treated mice. Aβ1-42-treated mice also increased in PDE4A, 4B and 4D expression, and decreased in PKA level. However, PKA inhibitor H89, but not PKG inhibitor KT5823, prevented resveratrol's effects on these parameters. Resveratrol also reversed Aβ1-42-induced decreases in phosphorylated cAMP response-element binding protein (pCREB), brain derived neurotrophic factor (BDNF) and anti-apoptotic factor BCl-2 expression, which were reversed by H89. These findings suggest that resveratrol reversing Aβ-induced learning and memory disorder may involve the regulation of neuronal inflammation and apoptosis via PDE4 subtypes related cAMP-CREB-BDNF signaling.

  13. Protective effects of phosphodiesterase-4-specific inhibitor rolipram on acute ischemia-reperfusion injury in rat kidney.

    Science.gov (United States)

    Mammadov, Emin; Aridogan, Ibrahim Atilla; Izol, Volkan; Acikalin, Arbil; Abat, Deniz; Tuli, Abdullah; Bayazit, Yildirim

    2012-12-01

    To investigate the effect of Rolipram, a phosphodiesterase-4-inhibitor, on renal ischemia-reperfusion injury (IRI) in rats. Thirty rats were divided into 5 different groups of 6 rats. Nothing was done to the control group. In the second group, the renal pedicle was clamped for 30 minutes. In the third group, 1 mg/kg of Rolipram was given by intraperitoneal injection 30 minutes before clamping. The fourth group received the same injection when the clamp was placed, as did the fifth group 30 minutes after the clamp was opened. Clamping time was set at 30 minutes. Twenty-four hours later, nephrectomy was performed in all the groups. Half of each kidney was examined histopathologically. Levels of biochemical agents, such as malondialdehyde, superoxide dismutase, and catalase, were measured in the other half. The malondialdehyde (MDA) levels significantly decreased and reached control levels in the group in which Rolipram was administered 30 minutes after reperfusion (P = .07). The catalase and superoxide dismutase activities obtained from renal homogentisates of the ischemia groups were evaluated; there were striking increases in tissue levels of these 2 enzymes in the groups in which Rolipram was administered during ischemia and 30 minutes after ischemia (P < .001). Histopathologically, there was no significant difference in inflammation between the Rolipram-administrated groups compared with group 1 (control) and group 2 (IRI). Tubular necrosis and apoptosis was significantly lower in group 5 than the other groups, except group 1 (P < .001). We suggest that in surgical procedures that can lead to renal IRI, the administration of Rolipram can decrease oxidative renal tissue damage and the severe deterioration of renal function. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Pharmacological characterization of a novel phosphodiesterase type 5 (PDE5) inhibitor lodenafil carbonate on human and rabbit corpus cavernosum.

    Science.gov (United States)

    Toque, Haroldo A; Teixeira, Cleber E; Lorenzetti, Raquel; Okuyama, Cristina E; Antunes, Edson; De Nucci, Gilberto

    2008-09-04

    Nitrergic nerves and endothelial cells release nitric oxide (NO) in the corpus cavernosum, a key mediator that stimulates soluble guanylyl cyclase to increase cGMP levels causing penile erection. Phosphodiesterase 5 (PDE5) inhibitors, such as sildenafil, prolong the NO effects by inhibiting cGMP breakdown. Here, we report a novel PDE5 inhibitor, lodenafil carbonate, (Bis-(2-{4-[4-ethoxy-3-(1-methyl-7-oxo-3-propyl-6,7-dihydro-1H-pyrazolo[4,3-d]pyrimidin-5-yl)-benzenesulfonyl]piperazin-1-yl}-ethyl)carbonate) that is a dimer of lodenafil. We therefore aimed to compare the effects of sildenafil, lodenafil and lodenafil carbonate on in vitro human and rabbit cavernosal relaxations, activity of crude PDE extracts from human platelets, as well as stability and metabolic studies in rat, dog and human plasma. Pharmacokinetic evaluations after intravenous and oral administration were performed in male beagles. Functional experiments were conducted using organ bath techniques. Pharmacokinetics was studied in beagles by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), following oral or intravascular administration. All PDE5 inhibitors tested concentration-dependently relaxed (0.001-100 microM) phenylephrine-precontracted rabbit and human corpus cavernosum. The cavernosal relaxations evoked by either acetylcholine (0.01-100 microM) or electrical field stimulation (EFS, 1-20 Hz) were markedly potentiated by sildenafil, lodenafil and lodenafil carbonate. Lodenafil carbonate was more potent to inhibit the cGMP hydrolysis in PDE extracts compared with lodenafil and sildenafil. Following intravascular and single oral administration of lodenafil carbonate, only lodenafil and norlodenafil were detected in vivo. These results indicate that lodenafil carbonate works as a prodrug, being lodenafil the active moiety of lodenafil carbonate.

  15. A Phase I clinical trial of lodenafil carbonate, a new phosphodiesterase Type 5 (PDE5) inhibitor, in healthy male volunteers.

    Science.gov (United States)

    Mendes, Gustavo D; dos Santos Filho, Hilton Oliveira; dos Santos Pereira, Alberto; Mendes, Fabiana D; Ilha, Jaime O; Alkharfy, Khalid M; De Nucci, Gilberto

    2012-12-01

    Lodenafil carbonate is a new phosphodiesterase Type 5 (PDE5) inhibitor used in treatment of erectile dysfunction. The present study was conducted to evaluate the safety, tolerability, and pharmacokinetics of lodenafil carbonate after administering ascending (1 - 100 mg) single oral doses to healthy male volunteers (n = 33). The study was an open label, dose-escalation, Phase I clinical trial involving the administration of single oral doses of lodenafil carbonate. Lodenafil carbonate was administered sequentially, escalating in single doses of 1 mg - 100 mg with a washout period of at least 1 week between each dose. The progression to the next dose was allowed after clinical and laboratory exams, Ambulatory Monitoring of Arterial Pressure (AMAP) without relevant clinical modifications and adverse events without clinical relevancy. Blood samples were collected at pre-dose, 0.25, 0.5, 0.75, 1, 1.25, 1.5, 1.75, 2, 2.5, 3, 3.5, 4, 4.5, 5, 6, 7, 8, 10, 12, 14, 16, 20 and 24 h post-dosing. Plasma samples for measurement of lodenafil carbonate and lodenafil were analyzed by liquid chromatography coupled to tandem mass spectrometry. No serious adverse events were observed, and none of the subjects discontinued the study due to intolerance. The AMAP measurements, clinical and laboratory exams and ECG revealed no significant changes even at higher doses. Lodenafil carbonate was not detected in any samples, indicating that it acts as a prodrug. The mean lodenafil pharmacokinetic parameters for tmax and t1/2 were 1.6 ( ± 0.4) h and 3.3 ( ± 1.1) h, respectively. This study demonstrated that lodenafil carbonate was well tolerated and showed a good safety profile in healthy male volunteers.

  16. Relaxation of isolated guinea-pig trachea by apigenin, a constituent of celery, via inhibition of phosphodiesterase.

    Science.gov (United States)

    Chen, Junn-Lain; Ko, Wun-Chang

    2017-09-15

    Apigenin, was reported to have vasodilatory effects by inhibiting Ca 2+ influx through both voltage- and receptor-operated calcium channels, but not by inhibiting cAMP- or cGMP-phosphodiesterases (PDEs) in rat thoracic aorta. However, apigenin was reported to inhibit PDE1, 2 and 3 in guinea-pig lung and heart. The aim of this study was to clarify that guinea-pig tracheal relaxation by apigenin whether via PDE inhibition. We isometrically recorded the tension of isolated guinea-pig tracheal segments on a polygraph. Antagonistic effects of apigenin against cumulative contractile agents or Ca 2+ induced contractions of the trachealis in normal or isotonic high-K + , Ca 2+ -free Krebs solution, respectively. Effects of apigenin (15 and 30μM) on the cumulative forskolin- and nitroprusside-induced relaxations to histamine (30μM)-induced precontraction were performed. The inhibitory effects of 30-300μM apigenin and 3-isobutyl-1-methylxanthine (IBMX, positive control) on the cAMP- and cGMP-PDEs were determined. Apigenin concentration-dependently but non-competitively inhibited cumulative histamine-, carbachol- or Ca 2+ -induced contractions in normal or in the depolarized (K + , 60mM) trachealis, suggesting that Ca 2+ influx through voltage-dependent calcium channels is inhibited. However, apigenin (15-30μM) parallel leftward shifted the concentration-response curves of forskolin and nitroprusside, and significantly increased the pD 2 values of these two cyclase activators. Both apigenin and IBMX, a reference drug, concentration (10-300μM)-dependently and significantly, but non-selectively inhibited the activities of cAMP- and cGMP-PDEs in the trachealis. In conclusion, the relaxant effect of apigenin may be due to inhibition of both enzyme activities and reduction of intracellular Ca 2+ by inhibiting Ca 2+ influx in the trachealis. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Phosphodiesterase (PDE5) inhibition assay for rapid detection of erectile dysfunction drugs and analogs in sexual enhancement products.

    Science.gov (United States)

    Santillo, Michael F; Mapa, Mapa S T

    2018-02-28

    Products marketed as dietary supplements for sexual enhancement are frequently adulterated with phosphodiesterase-5 (PDE5) inhibitors, which are erectile dysfunction drugs or their analogs that can cause adverse health effects. Due to widespread adulteration, a rapid screening assay was developed to detect PDE5 inhibitors in adulterated products. The assay employs fluorescence detection and is based on measuring inhibition of PDE5 activity, the pharmacological mechanism shared among the adulterants. Initially, the assay reaction scheme was established and characterized, followed by analysis of 9 representative PDE5 inhibitors (IC 50 , 0.4-4.0 ng mL -1 ), demonstrating sensitive detection in matrix-free solutions. Next, dietary supplements serving as matrix blanks (n = 25) were analyzed to determine matrix interference and establish a threshold value; there were no false positives. Finally, matrix blanks were spiked with 9 individual PDE5 inhibitors, along with several mixtures. All 9 adulterants were successfully detected (≤ 5 % false negative rate; n = 20) at a concentration of 1.00 mg g -1 , which is over 5 times lower than concentrations commonly encountered in adulterated products. A major distinction of the PDE5 inhibition assay is the ability to detect adulterants without prior knowledge of their chemical structures, demonstrating a broad-based detection capability that can address a continuously evolving threat of new adulterants. The PDE5 inhibition assay can analyze over 40 samples simultaneously within 15 minutes and involves a single incubation step and simple data analysis, all of which are advantageous for combating the widespread adulteration of sex-enhancement products. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.

  18. Osthol attenuates neutrophilic oxidative stress and hemorrhagic shock-induced lung injury via inhibition of phosphodiesterase 4.

    Science.gov (United States)

    Tsai, Yung-Fong; Yu, Huang-Ping; Chung, Pei-Jen; Leu, Yann-Lii; Kuo, Liang-Mou; Chen, Chun-Yu; Hwang, Tsong-Long

    2015-12-01

    Oxidative stress caused by neutrophils is an important pathogenic factor in trauma/hemorrhagic (T/H)-induced acute lung injury (ALI). Osthol, a natural coumarin found in traditional medicinal plants, has therapeutic potential in various diseases. However, the pharmacological effects of osthol in human neutrophils and its molecular mechanism of action remain elusive. In this study, our data showed that osthol potently inhibited the production of superoxide anion (O2(•-)) and reactive oxidants derived therefrom as well as expression of CD11b in N-formylmethionylleucylphenylalanine (FMLP)-activated human neutrophils. However, osthol inhibited neutrophil degranulation only slightly and it failed to inhibit the activity of subcellular NADPH oxidase. FMLP-induced phosphorylation of extracellular signal-regulated kinase (ERK) and protein kinase B (Akt) was inhibited by osthol. Notably, osthol increased the cAMP concentration and protein kinase A (PKA) activity in activated neutrophils. PKA inhibitors reversed the inhibitory effects of osthol, suggesting that these are mediated through cAMP/PKA-dependent inhibition of ERK and Akt activation. Furthermore, the activity of cAMP-specific phosphodiesterase (PDE) 4, but not PDE3 or PDE7, was significantly reduced by osthol. In addition, osthol reduced myeloperoxidase activity and pulmonary edema in rats subjected to T/H shock. In conclusion, our data suggest that osthol has effective anti-inflammatory activity in human neutrophils through the suppression of PDE4 and protects significantly against T/H shock-induced ALI in rats. Osthol may have potential for future clinical application as a novel adjunct therapy to treat lung inflammation caused by adverse circulatory conditions. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Phosphodiesterase 9A regulates central cGMP and modulates responses to cholinergic and monoaminergic perturbation in vivo.

    Science.gov (United States)

    Kleiman, Robin J; Chapin, Douglas S; Christoffersen, Curt; Freeman, Jody; Fonseca, Kari R; Geoghegan, Kieran F; Grimwood, Sarah; Guanowsky, Victor; Hajós, Mihály; Harms, John F; Helal, Christopher J; Hoffmann, William E; Kocan, Geralyn P; Majchrzak, Mark J; McGinnis, Dina; McLean, Stafford; Menniti, Frank S; Nelson, Fredrick; Roof, Robin; Schmidt, Anne W; Seymour, Patricia A; Stephenson, Diane T; Tingley, Francis David; Vanase-Frawley, Michelle; Verhoest, Patrick R; Schmidt, Christopher J

    2012-05-01

    Cyclic nucleotides are critical regulators of synaptic plasticity and participate in requisite signaling cascades implicated across multiple neurotransmitter systems. Phosphodiesterase 9A (PDE9A) is a high-affinity, cGMP-specific enzyme widely expressed in the rodent central nervous system. In the current study, we observed neuronal staining with antibodies raised against PDE9A protein in human cortex, cerebellum, and subiculum. We have also developed several potent, selective, and brain-penetrant PDE9A inhibitors and used them to probe the function of PDE9A in vivo. Administration of these compounds to animals led to dose-dependent accumulation of cGMP in brain tissue and cerebrospinal fluid, producing a range of biological effects that implied functional significance for PDE9A-regulated cGMP in dopaminergic, cholinergic, and serotonergic neurotransmission and were consistent with the widespread distribution of PDE9A. In vivo effects of PDE9A inhibition included reversal of the respective disruptions of working memory by ketamine, episodic and spatial memory by scopolamine, and auditory gating by amphetamine, as well as potentiation of risperidone-induced improvements in sensorimotor gating and reversal of the stereotypic scratching response to the hallucinogenic 5-hydroxytryptamine 2A agonist mescaline. The results suggested a role for PDE9A in the regulation of monoaminergic circuitry associated with sensory processing and memory. Thus, PDE9A activity regulates neuronal cGMP signaling downstream of multiple neurotransmitter systems, and inhibition of PDE9A may provide therapeutic benefits in psychiatric and neurodegenerative diseases promoted by the dysfunction of these diverse neurotransmitter systems.

  20. Multiple Behavior Phenotypes of the Fragile-X Syndrome Mouse Model Respond to Chronic Inhibition of Phosphodiesterase-4D (PDE4D)

    OpenAIRE

    Gurney, Mark E.; Cogram, Patricia; Deacon, Robert M; Rex, Christopher; Tranfaglia, Michael

    2017-01-01

    Fragile-X syndrome (FXS) patients display intellectual disability and autism spectrum disorder due to silencing of the X-linked, fragile-X mental retardation-1 (FMR1) gene. Dysregulation of cAMP metabolism is a consistent finding in patients and in the mouse and fly FXS models. We therefore explored if BPN14770, a prototypic phosphodiesterase-4D negative allosteric modulator (PDE4D-NAM) in early human clinical trials, might provide therapeutic benefit in the mouse FXS model. Daily treatment o...

  1. Selective inhibition of phosphodiesterases 4, 5 and 9 induces HSP20 phosphorylation and attenuates amyloid beta 1-42 mediated cytotoxicity

    OpenAIRE

    Cameron, Ryan T.; Whiteley, Ellanor; Day, Jon P.; Parachikova, Anna I.; Baillie, George S.

    2017-01-01

    Phosphodiesterase (PDE) inhibitors are currently under evaluation as agents that may facilitate the improvement of cognitive impairment associated with Alzheimer's disease. Our aim was to determine whether inhibitors of PDEs 4, 5 and 9 could alleviate the cytotoxic effects of amyloid beta 1?42 (A?1?42) via a mechanism involving the small heatshock protein HSP20. We show that inhibition of PDEs 4, 5 and 9 but not 3 induces the phosphorylation of HSP20 which, in turn, increases the colocalisati...

  2. Association of the polymorphism of codon 121 in the ecto-nucleotide pyrophosphatase/phosphodiesterase 1 gene with polycystic ovary syndrome in Chinese woman

    International Nuclear Information System (INIS)

    Shi, Y.; Chen, Z.; Zhang, P.; Zhao, Y.; You, L.; Sun, X.

    2008-01-01

    Objective was to determine the association of polymorphism of codon 121 in the ecto-nucleotide pyrophosphastase/phosphodiesterase 1 (E-NPP1/PC-1) gene in Chinese women with polycystic ovary syndrome (PCOS). A total of 51 PCOS patients and 61 healthy women from Chinese Han population from the Center Reproductive Medicine of Provincial Hospital affiliated to Shandong University from June 2005 to July 2006 were recruited for the determination of the polymorphism of the E-NPP/PC-1 gene. Genomic DNA was extracted from peripheral blood monocytes of patients and controls and genotyping of the gene was performed by using polymerase chain reaction, which was followed by sequencing. The frequency of the 121Q allele was 13 and 18%, respectively, in PCOS patients and healthy women, while the frequency of the 121K allele was 87 and 82% in the 2 groups. There is no significant difference in the E-NPP1/PC-1 polymorphism between PCOS patients and healthy controls among Chinese Han women. ecto-nucleotide pyrophosphatase/phosphodiesterase 1 polymorphism has no association with PCOS. Further studies are still needed to elucidate whether or not the E-NPP1/PC-1 gene has a functional role in PCOS. (author)

  3. Regulation of the pro-inflammatory cytokine osteopontin by GIP in adipocytes – A role for the transcription factor NFAT and phosphodiesterase 3B

    International Nuclear Information System (INIS)

    Omar, Bilal; Banke, Elin; Guirguis, Emilia; Aakesson, Lina; Manganiello, Vincent; Lyssenko, Valeriya; Groop, Leif; Gomez, Maria F.; Degerman, Eva

    2012-01-01

    Highlights: ► GIP stimulates lipogenesis and osteopontin expression in primary adipocytes. ► GIP-induced osteopontin expression is NFAT-dependent. ► Osteopontin expression is PDE3-dependent. ► Osteopontin expression is increased in PDE3B KO mice. -- Abstract: The incretin – glucose-dependent insulinotropic polypeptide (GIP) – and the pro-inflammatory cytokine osteopontin are known to have important roles in the regulation of adipose tissue functions. In this work we show that GIP stimulates lipogenesis and osteopontin expression in primary adipocytes. The GIP-induced increase in osteopontin expression was inhibited by the NFAT (the transcription factor nuclear factor of activated T-cells) inhibitor A-285222. Also, the NFAT kinase glycogen synthase kinase (GSK) 3 was upregulated by GIP. To test whether cAMP might be involved in GIP-mediated effects on osteopontin a number of strategies were used. Thus, the β3-adrenergic receptor agonist CL316,243 stimulated osteopontin expression, an effects which was mimicked by OPC3911, a specific inhibitor of phosphodiesterase 3. Furthermore, treatment of phosphodiesterase 3B knock-out mice with CL316,243 resulted in a dramatic upregulation of osteopontin in adipose tissue which was not the case in wild-type mice. In summary, we delineate mechanisms by which GIP stimulates osteopontin in adipocytes. Given the established link between osteopontin and insulin resistance, our data suggest that GIP by stimulating osteopontin expression, also could promote insulin resistance in adipocytes.

  4. The pde2 gene of Saccharomyces cerevisiae is allelic to rca1 and encodes a phosphodiesterase which protects the cell from extracellular cAMP.

    Science.gov (United States)

    Wilson, R B; Renault, G; Jacquet, M; Tatchell, K

    1993-07-05

    The high affinity cAMP phosphodiesterase, encoded by PDE2, is an important component of the cAMP-dependent protein kinase signaling system in Saccharomyces cerevisiae. An unexpected phenotype of pde2 mutants is sensitivity to external cAMP. This trait has been found independently for rca1 mutants and has been used to monitor the effects of cAMP on several biological processes. We demonstrate here that RCA1 is identical to PDE2. Further analysis of the phenotype of pde2 deletions reveal that exogenously added cAMP results in an increase in the internal level of cAMP. This increase slows down the rate of cell division by increasing the length of the G1 phase of the cell cycle and leads to increased cell volume. Also, cells with a disrupted PDE2 gene previously arrested by nutrient starvation rapidly lose thermotolerance when incubated with exogenous cAMP. From these observations we propose that a role of the PDE2-encoded phosphodiesterase may be to help insulate the internal cAMP pools from the external environment. This protective role might also be important in other eukaryotic organisms where cAMP is a key second messenger.

  5. Analysis of proton wires in the enzyme active site suggests a mechanism of c-di-GMP hydrolysis by the EAL domain phosphodiesterases.

    Science.gov (United States)

    Grigorenko, Bella L; Knyazeva, Marina A; Nemukhin, Alexander V

    2016-11-01

    We report for the first time a hydrolysis mechanism of the cyclic dimeric guanosine monophosphate (c-di-GMP) by the EAL domain phosphodiesterases as revealed by molecular simulations. A model system for the enzyme-substrate complex was prepared on the base of the crystal structure of the EAL domain from the BlrP1 protein complexed with c-di-GMP. The nucleophilic hydroxide generated from the bridging water molecule appeared in a favorable position for attack on the phosphorus atom of c-di-GMP. The most difficult task was to find a pathway for a proton transfer to the O3' atom of c-di-GMP to promote the O3'P bond cleavage. We show that the hydrogen bond network extended over the chain of water molecules in the enzyme active site and the Glu359 and Asp303 side chains provides the relevant proton wires. The suggested mechanism is consistent with the structural, mutagenesis, and kinetic experimental studies on the EAL domain phosphodiesterases. Proteins 2016; 84:1670-1680. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  6. Analysis of Prescriptions of Alpha-Blockers and Phosphodiesterase 5 Inhibitors from the Urology Department and Other Departments

    Directory of Open Access Journals (Sweden)

    Dong Hyuk Kang

    2011-12-01

    Full Text Available PurposeWe analyzed the prescriptions of alpha-blockers and phosphodiesterase 5 inhibitors (PDE5Is in the urology department as well as in other departments of the general hospital.MethodsWe investigated the frequency of prescription of alpha-blockers and PDE5Is from 3 general hospitals from January 1, 2007 to December 31, 2009. For alpha-blockers, data were collected from patients to whom alpha-blockers were prescribed from among patients recorded as having benign prostatic hyperplasia according to the 5th Korean Standard Classification of Diseases. For PDE5Is, data were collected from patients to whom PDE5Is were prescribed by the urology department and by other departments. Alpha-blockers were classified into tamsulosin, alfuzosin, doxazosin, and terazosin, whereas PDE5Is were classified into sildenafil, tadalafil, vardenafil, udenafil, and mirodenafil.ResultsAlpha-blockers were prescribed to 11,436 patients in total over 3 years, and the total frequency of prescriptions was 68,565. Among other departments, the nephrology department had the highest frequency of prescription of 3,225 (4.7%, followed by the cardiology (3,101, 4.5%, neurology (2,576, 3.8%, endocrinology (2,400, 3.5%, pulmonology (1,102, 1.6%, and family medicine (915, 1.3% departments in order. PDE5Is were prescribed to 2,854 patients in total over 3 years, and the total frequency of prescriptions was 10,558. The prescription frequency from the urology department was 4,900 (46.4%. Among other departments, the endocrinology department showed the highest prescription frequency of 3,488 (33.0%, followed by the neurology (542, 5.1%, cardiology (467, 4.4%, and family medicine (407, 3.9% departments in order.ConclusionsA high percentage of prescriptions of alpha-blockers and PDE5Is were from other departments. For more specialized medical care by urologists is required in the treatment of lower urinary tract symptoms and erectile dysfunction.

  7. Phosphodiesterase-5 inhibitor sildenafil preconditions adult cardiac myocytes against necrosis and apoptosis. Essential role of nitric oxide signaling.

    Science.gov (United States)

    Das, Anindita; Xi, Lei; Kukreja, Rakesh C

    2005-04-01

    We investigated the effect of sildenafil in protection against necrosis or apoptosis in cardiomyocytes. Adult mouse ventricular myocytes were treated with sildenafil (1 or 10 microM) for 1 h before 40 min of simulated ischemia (SI). Necrosis was determined by trypan blue exclusion and lactate dehydrogenase release following SI alone or plus 1 or 18 h of reoxygenation (RO). Apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated nick end labeling assay and mitochondrial membrane potential measured using a fluorescent probe 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolyl-carbocyanine iodide (JC-1). Sildenafil reduced necrosis as indicated by decrease in trypan blue-positive myocytes and leakage of lactate dehydrogenase compared with untreated cells after either SI or SI-RO. The number of terminal deoxynucleotidyl transferase-mediated nick end labeling-positive myocytes or loss of JC-1 fluorescence following SI and 18 h of RO was attenuated in the sildenafil-treated group with concomitant inhibition of caspase 3 activity. An early increase in Bcl-2 to Bax ratio with sildenafil treatment was also observed in myocytes after SI-RO. The increase of Bcl-2 expression by sildenafil was inhibited by nitric-oxide synthase (NOS) inhibitor, L-nitro-amino-methyl-ester. The drug also enhanced mRNA and protein content of inducible NOS (iNOS) and endothelial NOS (eNOS) in the myocytes. Sildenafil-induced protection against necrosis and apoptosis was absent in the myocytes derived from iNOS knock-out mice and was attenuated in eNOS knock-out myocytes. The up-regulation of Bcl-2 expression by sildenafil was also absent in iNOS-deficient myocytes. Reverse transcription-PCR, Western blots, and immunohistochemical assay confirmed the expression of phosphodiesterase-5 in mouse cardiomyocytes. These data provide strong evidence for a direct protective effect of sildenafil against necrosis and apoptosis through NO signaling pathway. The results may have possible

  8. Phosphodiesterase activity is regulated by CC2D1A that is implicated in non-syndromic intellectual disability

    KAUST Repository

    Altawashi, Azza

    2013-07-04

    Background: Cyclic adenosine 3?5?-monophosphate (cAMP) is a key regulator of many cellular processes, including in the neuronal system, and its activity is tuned by Phosphodiesterase (PDE) activation. Further, the CC2D1A protein, consisting of N-Terminal containing four DM14 domains and C-terminal containing C2 domain, was shown to regulate the cAMP-PKA pathway. A human deletion mutation lacking the fourth DM14 and the adjacent C2 domain results in Non Syndromic Intellectual Disability (NSID) also referred to as Non Syndromic Mental Retardation (NSMR). Findings. Here we demonstrate that in Mouse Embryonic Fibroblasts (MEF) CC2D1A co-localizes with PDE4D in the cytosol before cAMP stimulation and on the periphery after stimulation, and that the movement to the periphery requires the full-length CC2D1A. In CC2D1A mouse mutant cells, the absence of three of the four DM14 domains abolishes migration of the complex to the periphery and causes constitutive phosphorylation of PDE4D Serine 126 (Sssup126esup) via the cAMP-dependent protein kinase A (PKA) resulting in PDE4D hyperactivity. Suppressing PDE4D activity with Rolipram in turn restores the down-stream phosphorylation of the "cAMP response element-binding protein" (CREB) that is defective in mouse mutant cells. Conclusion: Our findings suggest that CC2D1A is a novel regulator of PDE4D. CC2D1A interacts directly with PDE4D regulating its activity and thereby fine-tuning cAMP-dependent downstream signaling. Based on our in vitro evidence we propose a model which links CC2D1A structure and function to cAMP homeostasis thereby affecting CREB phosphorylation. We speculate that CC2D1A and/or PDE4D may be promising targets for therapeutic interventions in many disorders with impaired PDE4D function such as NSID. 2013 Al-Tawashi and Gehring; licensee BioMed Central Ltd.

  9. Economic analysis of use of counterfeit drugs: health impairment risk of counterfeit phosphodiesterase type 5 inhibitor taken as an example.

    Science.gov (United States)

    Sugita, Minoru; Miyakawa, Michiko

    2010-07-01

    The size of the market for counterfeit drugs throughout the world is considerable. Many cases of health impairment due to counterfeits have been reported. The market share of counterfeits in drug markets in developed countries is smaller than that in developing countries. However, the size of the market for counterfeits of phosphodiesterase type 5 inhibitors (PDE5Is) used as anti-erectile-dysfunction drugs is not small. The purpose of the present study was to analyze the health impairment risk of taking the counterfeit PDE5Is and the convenience of obtaining the counterfeits in Japan, using an economic methodology in order to work out countermeasures for reducing the health impairment risk. Information was obtained by interviewing employees of pharmaceutical and chemical corporations in Japan. The size of the market for counterfeit PDE5Is in Japan was recently estimated to be about 2.5 times larger than that of genuine PDE5Is. The price of the counterfeits in their market is reported to be nearly equal to that of the genuine PDE5Is. An outbreak of severe hypoglycemia among users of counterfeit PDE5Is containing an antidiabetic drug in Singapore was reported in 2008, and seven patients remained comatose as a result of prolonged neuroglycopenia. Four of them subsequently died, so the health impairment risk due to counterfeit PDE5Is should not be ignored. In order to obtain a genuine PDE5I in Japan, a patient must be examined and have a prescription written at a medical institution, and buy it at a dispensing pharmacy. Focusing on the health impairment risk due to counterfeit PDE5Is and the convenience of obtaining the counterfeits in Japan, we analyzed the effects on the prices and quantities of PDE5Is in the market from demand and supply curves, using an economic methodology. From the analysis, it was shown that the health impairment risk due to the counterfeits is underestimated in the market in Japan. Physicians should warn their patients not to buy counterfeit

  10. Cyclic GMP-mediated memory enhancement in the object recognition test by inhibitors of phosphodiesterase-2 in mice.

    Science.gov (United States)

    Lueptow, Lindsay M; Zhan, Chang-Guo; O'Donnell, James M

    2016-02-01

    Cyclic nucleotide phosphodiesterase-2 (PDE2) is a potential therapeutic target for the treatment of cognitive dysfunction. Using the object recognition test (ORT), this study assessed the effects of two PDE2 inhibitors, Bay 60-7550 and ND7001, on learning and memory, and examined underlying mechanisms. To assess the role of PDE2 inhibition on phases of memory, Bay 60-7550 (3 mg/kg) was administered: 30 min prior to training; 0, 1, or 3 h after training; or 30 min prior to recall testing. To assess cyclic nucleotide involvement in PDE2 inhibitor-enhanced memory consolidation, either the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME; 20 mg/kg; intraperitoneal (IP)), soluble guanylyl cyclase inhibitor 1H-[-1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one (ODQ; 20 mg/kg; IP), protein kinase G inhibitor KT5823 (2.5 μg; intracerebroventricular (ICV)), or protein kinase A inhibitor H89 (1 μg; ICV) was administered 30 min prior to the PDE2 inhibitor Bay 60-7550 (3 mg/kg) or ND7001 (3 mg/kg). Changes in the phosphorylation of 3'5'-cyclic adenosine monophosphate (cAMP) response element binding protein (CREB) at Ser-133 and vasodilator-stimulated phosphoprotein (VASP) at Ser-239 were determined to confirm activation of cAMP and 3'5'-cyclic guanosine monophosphate (cGMP) signaling. Bay 60-7550 (3 mg/kg) enhanced memory of mice in the ORT when given 30 min prior to training, immediately after training, or 30 min prior to recall. Inhibitors of the cGMP pathway blocked the memory-enhancing effects of both Bay 60-7550 (3 mg/kg) and ND7001 (3 mg/kg) on early consolidation processes. Bay 60-7550 (3 mg/kg) enhanced phosphorylation of CREB and VASP, both targets of cGMP-dependent protein kinase (PKG). These results confirm a potential of PDE2, or components of its signaling pathway, as a therapeutic target for drug discovery focused on restoring memory function.

  11. Attenuation of ethanol abstinence-induced anxiety- and depressive-like behavior by the phosphodiesterase-4 inhibitor rolipram in rodents.

    Science.gov (United States)

    Gong, Mei-Fang; Wen, Rui-Ting; Xu, Ying; Pan, Jian-Chun; Fei, Ning; Zhou, Yan-Meng; Xu, Jiang-Ping; Liang, Jian-Hui; Zhang, Han-Ting

    2017-10-01

    Withdrawal symptoms stand as a core feature of alcohol dependence. Our previous results have shown that inhibition of phosphodiesterase-4 (PDE4) decreased ethanol seeking and drinking in alcohol-preferring rodents. However, little is known about whether PDE4 is involved in ethanol abstinence-related behavior. The objective of this study was to characterize the role of PDE4 in the development of anxiety- and depressive-like behavior induced by abstinence from ethanol exposure in different animal models. Using three rodent models of ethanol abstinence, we examined the effects of rolipram, a prototypical, selective PDE4 inhibitor, on (1) anxiety-like behavior induced by repeated ethanol abstinence in the elevated plus maze test in fawn-hooded (FH/Wjd) rats, (2) anxiety-like behavior in the open-field test and light-dark transition test following acute ethanol abstinence in C57BL/6J mice, and (3) anxiety- and depressive-like behavior induced by protracted ethanol abstinence in the elevated plus maze, forced-swim, and tail-suspension tests in C57BL/6J mice. Pretreatment with rolipram (0.1 or 0.2 mg/kg) significantly increased entries and time spent in the open arms of the elevated plus maze test in rats with repeated ethanol abstinence. Similarly, in mice with acute ethanol abstinence, administration of rolipram (0.25 or 0.5 mg/kg) dose-dependently increased the crossings in the central zone of the open-field test and duration and transitions on the light side of the light-dark transition test, suggesting anxiolytic-like effects of rolipram. Consistent with these, chronic treatment with rolipram (0.1, 0.3, or 1.0 mg/kg) increased entries in the open arms of the elevated plus maze test; it also reduced the increased duration of immobility in both the forced-swim and tail-suspension tests in mice after protracted ethanol abstinence, suggesting antidepressant-like effects of rolipram. These results provide the first demonstration for that PDE4 plays a role in modulating

  12. Cardiac effects of r-79595 and its isomers (r-80122 and r-80123) in an acute heart-failure model - a new class of cardiotonic agents with highly selective phosphodiesterase-iii inhibitory properties

    NARCIS (Netherlands)

    SCHNEIDER, J; BECK, E; HEERS, C; CONRAD, C; DECOURCELLES, DD; WILFFERT, B; Peters, Thies

    1992-01-01

    R 79595 (N-cyclohexyl-N-methyl-2-[[[phenyl (1,2,3,5-tetrahydro-2 oxoimidazo [2,1-b]-quinazolin-7-yl) methylene] amin] oxy] acetamide) and its isomers represent a novel class of compounds with phosphodiesterase (PDE) inhibitory and cardiotonic (positive inotropic) actions. The cardiac effects of this

  13. The Cyclic Di-GMP Phosphodiesterase Gene Rv1357c/BCG1419c Affects BCG Pellicle Production and In Vivo Maintenance.

    Science.gov (United States)

    Flores-Valdez, Mario Alberto; Aceves-Sánchez, Michel de Jesús; Pedroza-Roldán, César; Vega-Domínguez, Perla Jazmín; Prado-Montes de Oca, Ernesto; Bravo-Madrigal, Jorge; Laval, Françoise; Daffé, Mamadou; Koestler, Ben; Waters, Christopher M

    2015-02-01

    Bacteria living in a surface-attached community that contains a heterogeneous population, coated with an extracellular matrix, and showing drug tolerance (biofilms) are often linked to chronic infections. In mycobacteria, the pellicle mode of growth has been equated to an in vitro biofilm and meets several of the criteria mentioned above, while tuberculosis infection presents a chronic (latent) phase of infection. As mycobacteria lack most genes required to control biofilm production by other microorganisms, we deleted or expressed from the hsp60 strong promoter the only known c-di-GMP phosphodiesterase (PDE) gene in Mycobacterium bovis BCG. We found changes in pellicle production, cellular protein profiles, lipid production, resistance to nitrosative stress and maintenance in lungs and spleens of immunocompetent BALB/mice. Our results show that pellicle production and capacity to remain within the host are linked in BCG. © 2015 International Union of Biochemistry and Molecular Biology.

  14. Ectonucleotide pyrophosphatase/phosphodiesterase (E-NPP) and adenosine deaminase (ADA) activities in prostate cancer patients: influence of Gleason score, treatment and bone metastasis.

    Science.gov (United States)

    Battisti, Vanessa; Maders, Liési D K; Bagatini, Margarete D; Battisti, Iara E; Bellé, Luziane P; Santos, Karen F; Maldonado, Paula A; Thomé, Gustavo R; Schetinger, Maria R C; Morsch, Vera M

    2013-04-01

    The relation between adenine nucleotides and cancer has already been described in literature. Considering that the enzymes ectonucleotide pyrophosphatase/phosphodiesterase (E-NPP) and adenosine deaminase (ADA) act together to control nucleotide levels, we aimed to investigate the role of these enzymes in prostate cancer (PCa). E-NPP and ADA activities were determined in serum and platelets of PCa patients and controls. We also verified the influence of the Gleason score, bone metastasis and treatment in the enzyme activities. Platelets and serum E-NPP activity increased, whereas ADA activity in serum decreased in PCa patients. In addition, Gleason score, metastasis and treatment influenced E-NPP and ADA activities. We may propose that E-NPP and ADA are involved in the development of PCa. Moreover, E-NPP and ADA activities are modified in PCa patients with distinct Gleason score, with bone metastasis, as well as in patients under treatment. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  15. Regulation of the pro-inflammatory cytokine osteopontin by GIP in adipocytes - A role for the transcription factor NFAT and phosphodiesterase 3B

    Energy Technology Data Exchange (ETDEWEB)

    Omar, Bilal [Department of Experimental Medical Sciences, Diabetes, Metabolism and Endocrinology, Biomedical Center, Lund University, Lund (Sweden); Banke, Elin, E-mail: elin.banke@med.lu.se [Department of Experimental Medical Sciences, Diabetes, Metabolism and Endocrinology, Biomedical Center, Lund University, Lund (Sweden); Guirguis, Emilia [Cardiovascular Pulmonary Branch, NHLBI, NIH, Bethesda, MD (United States); Aakesson, Lina [Department of Clinical Sciences, Diabetes and Celiac Disease Unit, Clinical Research Centre, Lund University, Malmoe (Sweden); Manganiello, Vincent [Cardiovascular Pulmonary Branch, NHLBI, NIH, Bethesda, MD (United States); Lyssenko, Valeriya; Groop, Leif [Department of Clinical Sciences, Diabetes and Endocrinology, Clinical Research Centre, Lund University, Malmoe (Sweden); Gomez, Maria F. [Department of Clinical Sciences, Vascular ET Coupling, Clinical Research Centre, Lund University, Malmoe (Sweden); Degerman, Eva [Department of Experimental Medical Sciences, Diabetes, Metabolism and Endocrinology, Biomedical Center, Lund University, Lund (Sweden)

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer GIP stimulates lipogenesis and osteopontin expression in primary adipocytes. Black-Right-Pointing-Pointer GIP-induced osteopontin expression is NFAT-dependent. Black-Right-Pointing-Pointer Osteopontin expression is PDE3-dependent. Black-Right-Pointing-Pointer Osteopontin expression is increased in PDE3B KO mice. -- Abstract: The incretin - glucose-dependent insulinotropic polypeptide (GIP) - and the pro-inflammatory cytokine osteopontin are known to have important roles in the regulation of adipose tissue functions. In this work we show that GIP stimulates lipogenesis and osteopontin expression in primary adipocytes. The GIP-induced increase in osteopontin expression was inhibited by the NFAT (the transcription factor nuclear factor of activated T-cells) inhibitor A-285222. Also, the NFAT kinase glycogen synthase kinase (GSK) 3 was upregulated by GIP. To test whether cAMP might be involved in GIP-mediated effects on osteopontin a number of strategies were used. Thus, the {beta}3-adrenergic receptor agonist CL316,243 stimulated osteopontin expression, an effects which was mimicked by OPC3911, a specific inhibitor of phosphodiesterase 3. Furthermore, treatment of phosphodiesterase 3B knock-out mice with CL316,243 resulted in a dramatic upregulation of osteopontin in adipose tissue which was not the case in wild-type mice. In summary, we delineate mechanisms by which GIP stimulates osteopontin in adipocytes. Given the established link between osteopontin and insulin resistance, our data suggest that GIP by stimulating osteopontin expression, also could promote insulin resistance in adipocytes.

  16. Hesperidin-3′-O-Methylether Is More Potent than Hesperidin in Phosphodiesterase Inhibition and Suppression of Ovalbumin-Induced Airway Hyperresponsiveness

    Directory of Open Access Journals (Sweden)

    You-Lan Yang

    2012-01-01

    Full Text Available Hesperidin is present in the traditional Chinese medicine, “Chen Pi,” and recently was reported to have anti-inflammatory effects. Therefore, we were interested in comparing the effects of hesperidin and hesperidin-3′-O-methylether on phosphodiesterase inhibition and airway hyperresponsiveness (AHR in a murine model of asthma. In the present results, hesperidin-3′-O-methylether, but not hesperidin, at 30 μmol/kg (p.o. significantly attenuated the enhanced pause (Penh value, suppressed the increases in numbers of total inflammatory cells, macrophages, lymphocytes, neutrophils, and eosinophils, suppressed total and OVA-specific immunoglobulin (IgE levels in the serum and BALF, and enhanced the level of total IgG2a in the serum of sensitized and challenged mice, suggesting that hesperidin-3′-O-methylether is more potent than hesperidin in suppression of AHR and immunoregulation. The different potency between them may be due to their aglycons, because these two flavanone glycosides should be hydrolyzed by β-glucosidase after oral administration. Neither influenced xylazine/ketamine-induced anesthesia, suggesting that they may have few or no adverse effects, such as nausea, vomiting, and gastric hypersecretion. In conclusion, hesperidin-3′-O-methylether is more potent in phosphodiesterase inhibition and suppression of AHR and has higher therapeutic (PDE4H/PDE4L ratio than hesperidin. Thus, hesperidin-3′-O-methylether may have more potential for use in treating allergic asthma and chronic obstructive pulmonary disease.

  17. Benefits and risks of testosterone treatment for hypoactive sexual desire disorder in women: a critical review of studies published in the decades preceding and succeeding the advent of phosphodiesterase type 5 inhibitors

    Directory of Open Access Journals (Sweden)

    Sandra Léa Bonfim Reis

    2014-04-01

    Full Text Available With advancing age, there is an increase in the complaints of a lack of a libido in women and erectile dysfunction in men. The efficacy of phosphodiesterase type 5 inhibitors, together with their minimal side effects and ease of administration, revolutionized the treatment of erectile dysfunction. For women, testosterone administration is the principal treatment for hypoactive sexual desire disorder. We sought to evaluate the use of androgens in the treatment of a lack of libido in women, comparing two periods, i.e., before and after the advent of the phosphodiesterase type 5 inhibitors. We also analyzed the risks and benefits of androgen administration. We searched the Latin-American and Caribbean Health Sciences Literature, Cochrane Library, Excerpta Medica, Scientific Electronic Library Online, and Medline (PubMed databases using the search terms disfunção sexual feminina/female sexual dysfunction, desejo sexual hipoativo/female hypoactive sexual desire disorder, testosterona/testosterone, terapia androgênica em mulheres/androgen therapy in women, and sexualidade/sexuality as well as combinations thereof. We selected articles written in English, Portuguese, or Spanish. After the advent of phosphodiesterase type 5 inhibitors, there was a significant increase in the number of studies aimed at evaluating the use of testosterone in women with hypoactive sexual desire disorder. However, the risks and benefits of testosterone administration have yet to be clarified.

  18. PdeH, a high-affinity cAMP phosphodiesterase, is a key regulator of asexual and pathogenic differentiation in Magnaporthe oryzae.

    Directory of Open Access Journals (Sweden)

    Ravikrishna Ramanujam

    2010-05-01

    Full Text Available Cyclic AMP-dependent pathways mediate the communication between external stimuli and the intracellular signaling machinery, thereby influencing important aspects of cellular growth, morphogenesis and differentiation. Crucial to proper function and robustness of these signaling cascades is the strict regulation and maintenance of intracellular levels of cAMP through a fine balance between biosynthesis (by adenylate cyclases and hydrolysis (by cAMP phosphodiesterases. We functionally characterized gene-deletion mutants of a high-affinity (PdeH and a low-affinity (PdeL cAMP phosphodiesterase in order to gain insights into the spatial and temporal regulation of cAMP signaling in the rice-blast fungus Magnaporthe oryzae. In contrast to the expendable PdeL function, the PdeH activity was found to be a key regulator of asexual and pathogenic development in M. oryzae. Loss of PdeH led to increased accumulation of intracellular cAMP during vegetative and infectious growth. Furthermore, the pdeHDelta showed enhanced conidiation (2-3 fold, precocious appressorial development, loss of surface dependency during pathogenesis, and highly reduced in planta growth and host colonization. A pdeHDelta pdeLDelta mutant showed reduced conidiation, exhibited dramatically increased (approximately 10 fold cAMP levels relative to the wild type, and was completely defective in virulence. Exogenous addition of 8-Br-cAMP to the wild type simulated the pdeHDelta defects in conidiation as well as in planta growth and development. While a fully functional GFP-PdeH was cytosolic but associated dynamically with the plasma membrane and vesicular compartments, the GFP-PdeL localized predominantly to the nucleus. Based on data from cAMP measurements and Real-Time RTPCR, we uncover a PdeH-dependent biphasic regulation of cAMP levels during early and late stages of appressorial development in M. oryzae. We propose that PdeH-mediated sustenance and dynamic regulation of cAMP signaling

  19. Postulated vasoactive neuropeptide immunopathology affecting the blood–brain/blood–spinal barrier in certain neuropsychiatric fatigue-related conditions: A role for phosphodiesterase inhibitors in treatment?

    Directory of Open Access Journals (Sweden)

    Sonya Marshall-Gradisnik

    2008-10-01

    contribute to the BBB and BSB integrity and contain PACAP and VIP receptors. Autoimmunity of these receptors would likely affect BBB and VRS function and therefore may contribute to the etiology of these conditions by affecting CNS and immunological homeostasis, including promoting neuropsychological symptomatology. PACAP and VIP, as potent activators of adenylate cyclase (AC, have a key role in cyclic adenosine monophosphate (cAMP production affecting regulatory T cell (Treg and other immune functions. Phosphodiesterase enzymes (PDEs catalyze cAMP and PDE inhibitors (PDEIs maintain cAMP levels and have proven and well known therapeutic benefit in animal models such as experimental allergic encephalomyelitis (EAE. Therefore PDEIs may have a role in therapy for certain neuropsychiatric fatigue-related conditions.Keywords: vasoactive neuropeptides, multiple sclerosis, Parkinson’s disease, chronic fatigue syndrome, phosphodiesterase inhibitors, cyclic AMP, adenylate cyclase, Virchow–Robin spaces

  20. Hesperetin-7,3'-O-dimethylether selectively inhibits phosphodiesterase 4 and effectively suppresses ovalbumin-induced airway hyperresponsiveness with a high therapeutic ratio

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    Yang You-Lan

    2011-11-01

    Full Text Available Abstract Background Hesperetin was reported to selectively inhibit phosphodiesterase 4 (PDE4. While hesperetin-7,3'-O-dimethylether (HDME is a synthetic liposoluble hesperetin. Therefore, we were interested in investigating its selectivity on PDE4 and binding ability on high-affinity rolipram-binding sites (HARBs in vitro, and its effects on ovalbumin-induced airway hyperresponsiveness in vivo, and clarifying its potential for treating asthma and chronic obstructive pulmonary disease (COPD. Methods PDE1~5 activities were measured using a two-step procedure. The binding of HDME on high-affinity rolipram-binding sites was determined by replacing 2 nM [3H]-rolipram. AHR was assessed using the FlexiVent system and barometric plethysmography. Inflammatory cells were counted using a hemocytometer. Cytokines were determined using mouse T helper (Th1/Th2 cytokine CBA kits, and total immunoglobulin (IgE or IgG2a levels were done using ELISA method. Xylazine (10 mg/kg/ketamine (70 mg/kg-induced anesthesia was performed. Results HDME revealed selective phosphodiesterase 4 (PDE4 inhibition with a therapeutic (PDE4H/PDE4L ratio of 35.5 in vitro. In vivo, HDME (3~30 μmol/kg, orally (p.o. dose-dependently and significantly attenuated the airway resistance (RL and increased lung dynamic compliance (Cdyn, and decreased enhanced pause (Penh values induced by methacholine in sensitized and challenged mice. It also significantly suppressed the increases in the numbers of total inflammatory cells, macrophages, lymphocytes, neutrophils, and eosinophils, and levels of cytokines, including interleukin (IL-2, IL-4, IL-5, interferon-γ, and tumor necrosis factor-α in bronchoalveolar lavage fluid (BALF of these mice. In addition, HDME (3~30 μmol/kg, p.o. dose-dependently and significantly suppressed total and ovalbumin-specific immunoglobulin (IgE levels in the BALF and serum, and enhanced IgG2a level in the serum of these mice. Conclusions HDME exerted anti

  1. Diminished responsiveness to dobutamine as an inotrope in mice with cecal ligation and puncture-induced sepsis: attribution to phosphodiesterase 4 upregulation.

    Science.gov (United States)

    Sakai, Mari; Suzuki, Tokiko; Tomita, Kengo; Yamashita, Shigeyuki; Palikhe, Sailesh; Hattori, Kohshi; Yoshimura, Naoki; Matsuda, Naoyuki; Hattori, Yuichi

    2017-06-01

    Dobutamine has been used in septic shock for many years as an only inotrope, but its benefit has been questioned. We weighed the effects of dobutamine and milrinone as inotropes in mice with cecal ligation and puncture (CLP)-induced polymicrobial sepsis. CLP-induced septic mice exhibited significant cardiac inflammation, as indicated by greatly increased mRNAs of proinflammatory cytokines and robust infiltration of inflammatory cells in the ventricular myocardium. Elevations of plasma cardiac troponin-I showed cardiac injury in CLP mice. Noninvasive echocardiographic assessment of cardiac function revealed that despite preserved left ventricular function in the presence of fluid replacement, the dobutamine inotropic response was significantly impaired in CLP mice compared with sham-operated controls. By contrast, milrinone exerted inotropic effects in sham-operated and CLP mice in an equally effective manner. Surface expression levels of β 1 -adrenoceptors and α-subunits of three main G protein families in the myocardium were unaffected by CLP-induced sepsis. Plasma cAMP levels were significantly elevated in both sham-operated and CLP mice in response to milrinone but only in sham-operated controls in response to dobutamine. Of phosphodiesterase (PDE) isoforms, PDE4D, but not PDE3A, both of which are responsible for cardiac cAMP hydrolysis, was significantly upregulated in CLP mouse myocardium. We define a novel mechanism for the impaired responsiveness to dobutamine as an inotrope in sepsis, and understanding the role of PDE4D in modulating cardiac functional responsiveness in sepsis may open the potential of a PDE4D-targeted therapeutic option in septic patients with low cardiac output who have a need for inotropic support. NEW & NOTEWORTHY Advisability of the usefulness of dobutamine in septic shock management is limited. Here, we reveal that the effect of dobutamine as a positive inotrope is impaired in mice with cecal ligation and puncture-induced sepsis

  2. Phosphodiesterase type 5 inhibitor administered immediately after radical prostatectomy temporarily increases the need for incontinence pads, but improves final continence status

    Directory of Open Access Journals (Sweden)

    Yasuhiro Kaiho

    2016-09-01

    Full Text Available Purpose: To evaluate the effects of phosphodiesterase type 5 inhibitor (PDE5i on urinary continence recovery after bilateral nerve-sparing radical prostatectomy (BNSRP. Materials and Methods: Between 2002 and 2012, 137 of 154 consecutive patients who underwent BNSRP in our institution retrospectively divided into 3 groups that included patients taking PDE5i immediately after surgery (immediate PDE5i group, n=41, patients starting PDE5i at an outpatient clinic after discharge (PDE5i group, n=56, and patients taking no medication (non-PDE5i group, n=40. Using self-administered questionnaires, the proportion of patients who did not require incontinence pads (pad-free patients was calculated preoperatively and at 1, 3, 6, 12, 18, and 24 months after BNSRP. Severity of incontinence was determined based on the pad numbers and then compared among the 3 groups. Results: Proportions of pad-free patients and severity of incontinence initially deteriorated in all of the groups to the lowest values soon after undergoing BNSRP, with gradual improvement noted thereafter. The deterioration was most prominent in the immediate PDE5i group. As compared to the non-PDE5i group, both the PDE5i and immediate PDE5i groups exhibited a better final continence status. Conclusions: PDE5i improves final continence status. However, administration of PDE5i immediately after surgery causes a distinct temporary deterioration in urinary incontinence.

  3. Beneficial long term effect of a phosphodiesterase-5-inhibitor in cirrhotic portal hypertension: A case report with 8 years follow-up.

    Science.gov (United States)

    Deibert, Peter; Lazaro, Adhara; Stankovic, Zoran; Schaffner, Denise; Rössle, Martin; Kreisel, Wolfgang

    2018-01-21

    Non-selective beta-blockers are the mainstay of medical therapy for portal hypertension in liver cirrhosis. Inhibitors of phosphodiesterase-5 (PDE-5-inhibitors) reduce portal pressure in the acute setting by > 10% which may suggest a long-term beneficial effect. Currently, there is no available data on long-term treatment of portal hypertension with PDE-5-inhibitors. This case of a patient with liver cirrhosis secondary to autoimmune liver disease with episodes of bleeding from esophageal varices is the first documented case in which a treatment with a PDE-5-inhibitor for eight years was monitored. In the acute setting, the PDE-5-inhibitor Vardenafil lowered portal pressure by 13%. The portal blood flow increased by 28% based on Doppler sonography and by 16% using MRI technique. As maintenance medication the PDE-5-inhibitor Tadalafil was used for eight consecutive years with comparable effects on portal pressure and portal blood flow. There were no recurrence of bleeding and no formation of new varices. Influencing the NO-pathway by the use of PDE-5 inhibitors may have long-term beneficial effects in compensated cirrhosis.

  4. Direct interaction of the inhibitory gamma-subunit of Rod cGMP phosphodiesterase (PDE6) with the PDE6 GAFa domains.

    Science.gov (United States)

    Muradov, Khakim G; Granovsky, Alexey E; Schey, Kevin L; Artemyev, Nikolai O

    2002-03-26

    Retinal rod and cone cGMP phosphodiesterases (PDE6 family) function as the effector enzyme in the vertebrate visual transduction cascade. The activity of PDE6 catalytic subunits is controlled by the Pgamma-subunits. In addition to the inhibition of cGMP hydrolysis at the catalytic sites, Pgamma is known to stimulate a noncatalytic binding of cGMP to the regulatory GAFa-GAFb domains of PDE6. The latter role of Pgamma has been attributed to its polycationic region. To elucidate the structural basis for the regulation of cGMP binding to the GAF domains of PDE6, a photoexcitable peptide probe corresponding to the polycationic region of Pgamma, Pgamma-21-45, was specifically cross-linked to rod PDE6alphabeta. The site of Pgamma-21-45 cross-linking was localized to Met138Gly139 within the PDE6alpha GAFa domain using mass spectrometric analysis. Chimeras between PDE5 and cone PDE6alpha', containing GAFa and/or GAFb domains of PDE6alpha' have been generated to probe a potential role of the GAFb domains in binding to Pgamma. Analysis of the inhibition of the PDE5/PDE6alpha' chimeras by Pgamma supported the role of PDE6 GAFa but not GAFb domains in the interaction with Pgamma. Our results suggest that a direct binding of the polycationic region of Pgamma to the GAFa domains of PDE6 may lead to a stabilization of the noncatalytic cGMP-binding sites.

  5. Multiple Behavior Phenotypes of the Fragile-X Syndrome Mouse Model Respond to Chronic Inhibition of Phosphodiesterase-4D (PDE4D).

    Science.gov (United States)

    Gurney, Mark E; Cogram, Patricia; Deacon, Robert M; Rex, Christopher; Tranfaglia, Michael

    2017-11-07

    Fragile-X syndrome (FXS) patients display intellectual disability and autism spectrum disorder due to silencing of the X-linked, fragile-X mental retardation-1 (FMR1) gene. Dysregulation of cAMP metabolism is a consistent finding in patients and in the mouse and fly FXS models. We therefore explored if BPN14770, a prototypic phosphodiesterase-4D negative allosteric modulator (PDE4D-NAM) in early human clinical trials, might provide therapeutic benefit in the mouse FXS model. Daily treatment of adult male fmr1 C57Bl6 knock-out mice with BPN14770 for 14 days reduced hyperarousal, improved social interaction, and improved natural behaviors such as nesting and marble burying as well as dendritic spine morphology. There was no decrement in behavioral scores in control C57Bl6 treated with BPN14770. The behavioral benefit of BPN14770 persisted two weeks after washout of the drug. Thus, BPN14770 may be useful for the treatment of fragile-X syndrome and other disorders with decreased cAMP signaling.

  6. Exploring pyrazolo[3,4-d]pyrimidine phosphodiesterase 1 (PDE1) inhibitors: a predictive approach combining comparative validated multiple molecular modelling techniques.

    Science.gov (United States)

    Amin, Sk Abdul; Bhargava, Sonam; Adhikari, Nilanjan; Gayen, Shovanlal; Jha, Tarun

    2018-02-01

    Phosphodiesterase 1 (PDE1) is a potential target for a number of neurodegenerative disorders such as Schizophrenia, Parkinson's and Alzheimer's diseases. A number of pyrazolo[3,4-d]pyrimidine PDE1 inhibitors were subjected to different molecular modelling techniques [such as regression-based quantitative structure-activity relationship (QSAR): multiple linear regression, support vector machine and artificial neural network; classification-based QSAR: Bayesian modelling and Recursive partitioning; Monte Carlo based QSAR; Open3DQSAR; pharmacophore mapping and molecular docking analyses] to get a detailed knowledge about the physicochemical and structural requirements for higher inhibitory activity. The planarity of the pyrimidinone ring plays an important role for PDE1 inhibition. The N-methylated function at the 5th position of the pyrazolo[3,4-d]pyrimidine core is required for interacting with the PDE1 enzyme. The cyclopentyl ring fused with the parent scaffold is necessary for PDE1 binding potency. The phenylamino substitution at 3rd position is crucial for PDE1 inhibition. The N2-substitution at the pyrazole moiety is important for PDE1 inhibition compared to the N1-substituted analogues. Moreover, the p-substituted benzyl side chain at N2-position helps to enhance the PDE1 inhibitory profile. Depending on these observations, some new molecules are predicted that may possess better PDE1 inhibition.

  7. Necrotic enteritis locus 1 diguanylate cyclase and phosphodiesterase (cyclic-di-GMP) gene mutation attenuates virulence in an avian necrotic enteritis isolate of Clostridium perfringens.

    Science.gov (United States)

    Parreira, Valeria R; Ojha, Shivani; Lepp, Dion; Mehdizadeh Gohari, Iman; Zhou, Hongzhuan; Susta, Leonardo; Gong, Jianhua; Prescott, John F

    2017-09-01

    Necrotic enteritis (NE) caused by netB-positive strains of Clostridium perfringens is an important disease of intensively-reared broiler chickens. It is widely controlled by antibiotic use, but this practice that has come under increasing scrutiny and alternative approaches are required. As part of the search for alternative approaches over the last decade, advances have been made in understanding its pathogenesis but much remains to be understood and applied to the control of NE. The objective of this work was to assess the effect on virulence of mutation of the cyclic-di-GMP signaling genes present on the large pathogenicity locus (NELoc-1) in the tcp-encoding conjugative virulence plasmid, pNetB. For this purpose, the diguanylate cyclase (dgc) and phosphodiesterase (pde) genes were individually insertionally inactivated and the two mutants were subsequently complemented with their respective genes. Southern blotting showed that a single gene insertion was present. Mutation of either gene resulted in almost total attenuation of the mutants to cause NE in experimentally-infected broiler chickens, which was fully restored in each case by complementation of the respective mutated gene. Production of NetB-associated cytotoxicity for Leghorn male hepatoma (LMH) cells was unaffected in mutants. We conclude that the cyclic-di-GMP signaling system is important in controlling virulence in a NE C. perfringens strain and might be a target for control of the disease. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Early and rapid development of insulin resistance, islet dysfunction and glucose intolerance after high-fat feeding in mice overexpressing phosphodiesterase 3B

    DEFF Research Database (Denmark)

    Walz, Helena A; Härndahl, Linda; Wierup, Nils

    2006-01-01

    Inadequate islet adaptation to insulin resistance leads to glucose intolerance and type 2 diabetes. Here we investigate whether beta-cell cAMP is crucial for islet adaptation and prevention of glucose intolerance in mice. Mice with a beta-cell-specific, 2-fold overexpression of the c......AMP-degrading enzyme phosphodiesterase 3B (RIP-PDE3B/2 mice) were metabolically challenged with a high-fat diet. We found that RIP-PDE3B/2 mice early and rapidly develop glucose intolerance and insulin resistance, as compared with wild-type littermates, after 2 months of high-fat feeding. This was evident from...... did not reveal reduced insulin sensitivity in these tissues. Significant steatosis was noted in livers from high-fat-fed wild-type and RIP-PDE3B/2 mice and liver triacyl-glycerol content was 3-fold higher than in wild-type mice fed a control diet. Histochemical analysis revealed severe islet...

  9. Simultaneous Detection of Three Phosphodiesterase Type 5 Inhibitors and Eight of Their Analogs in Lifestyle Products and Screening for Adulterants by High-Performance Thin-Layer Chromatography.

    Science.gov (United States)

    Do, Tiên T K; Theocharis, Grigorios; Reich, Eike

    2015-01-01

    An HPTLC method is proposed to permit effective screening for the presence of three phosphodiesterase type 5 inhibitors (PDE5-Is; sildenafil, vardenafil, and tadalafil) and eight of their analogs (hydroxyacetildenafil, homosildenafil, thiohomosildenafil, acetildenafil, acetaminotadalafil, propoxyphenyl hydroxyhomosildenafil, hydroxyhomosildenafil, and hydroxythiohomosildenafil) in finished products, including tablets, capsules, chocolate, instant coffee, syrup, and chewing gum. For all the finished products, the same simple sample preparation may be applied: ultrasound-assisted extraction in 10 mL methanol for 30 min followed by centrifugation. The Rf values of individual HPTLC bands afford preliminary identification of potential PDE5-Is. Scanning densitometry capabilities enable comparison of the unknown UV spectra with those of known standard compounds and allow further structural insight. Mass spectrometric analysis of the material derived from individual zones supplies an additional degree of confidence. Significantly, the proposed screening technique allows focus on the already known PDE5 Is and provides a platform for isolation and chemical categorization of the newly-synthesized analogs. Furthermore, the scope could be expanded to other therapeutic categories (e.g., analgesics, antidiabetics, and anorexiants) that are occasionally coadulterated along with the PDE5-Is. The method was successfully applied to screening of 45 commercial lifestyle products. Of those, 31 products tested positive for at least one illegal component (sildenafil, tadalafil, propoxyphenyl hydroxyhomosildenafil, or dimethylsildenafil).

  10. Phosphodiesterase-1b (Pde1b) knockout mice are resistant to forced swim and tail suspension induced immobility and show upregulation of Pde10a.

    Science.gov (United States)

    Hufgard, Jillian R; Williams, Michael T; Skelton, Matthew R; Grubisha, Olivera; Ferreira, Filipa M; Sanger, Helen; Wright, Mary E; Reed-Kessler, Tracy M; Rasmussen, Kurt; Duman, Ronald S; Vorhees, Charles V

    2017-06-01

    Major depressive disorder is a leading cause of suicide and disability. Despite this, current antidepressants provide insufficient efficacy in more than 60% of patients. Most current antidepressants are presynaptic reuptake inhibitors; postsynaptic signal regulation has not received as much attention as potential treatment targets. We examined the effects of disruption of the postsynaptic cyclic nucleotide hydrolyzing enzyme, phosphodiesterase (PDE) 1b, on depressive-like behavior and the effects on PDE1B protein in wild-type (WT) mice following stress. Littermate knockout (KO) and WT mice were tested in locomotor activity, tail suspension (TST), and forced swim tests (FST). FST was also used to compare the effects of two antidepressants, fluoxetine and bupropion, in KO versus WT mice. Messenger RNA (mRNA) expression changes were also determined. WT mice underwent acute or chronic stress and markers of stress and PDE1B expression were examined. Pde1b KO mice exhibited decreased TST and FST immobility. When treated with antidepressants, both WT and KO mice showed decreased FST immobility and the effect was additive in KO mice. Mice lacking Pde1b had increased striatal Pde10a mRNA expression. In WT mice, acute and chronic stress upregulated PDE1B expression while PDE10A expression was downregulated after chronic but not acute stress. PDE1B is a potential therapeutic target for depression treatment because of the antidepressant-like phenotype seen in Pde1b KO mice.

  11. Phosphodiesterase-5 inhibitors and their analogues as adulterants of herbal and food products: analysis of the Malaysian market, 2014-16.

    Science.gov (United States)

    Bujang, Nur Baizura; Chee, Chin Fei; Heh, Choon Han; Rahman, Noorsaadah Abd; Buckle, Michael J C

    2017-07-01

    Adulteration of herbal health supplements with phosphodiesterase-5 (PDE-5) inhibitors and their analogues is becoming a worldwide problem. The aim of this study was to investigate herbal and food products sold in the Malaysian market for the presence of these adulterants. Sixty-two products that claim to enhance men's sexual health were sampled between April 2014 and April 2016. These products included unregistered products seized by the Pharmacy Enforcement Division of the Ministry of Health (n = 39), products sent to the National Pharmaceutical Regulatory Agency for pre-registration testing (n = 9) and products investigated under the post-registration market surveillance programme (n = 14). The products were tested against an in-house spectral library consisting of 61 PDE-5 inhibitors and analogues using a validated liquid chromatography-mass spectrometry ion-trap-time-of-flight (LC-MS IT-TOF) method. Thirty-two (82%) of the unregistered products and two (14%) of the registered products were found to be adulterated with at least one PDE-5 inhibitor or analogue, while none of the pre-registration products contained adulterants. A total of 16 different adulterants were detected and 36% of the adulterated products contained a mixture of two or more adulterants. This study has demonstrated that the adulteration of unregistered herbal products in the Malaysian market is an alarming issue that needs to be urgently addressed by the relevant authorities.

  12. Constitutively active signaling by the G protein βγ-subunit mediates intrinsically increased phosphodiesterase-4 activity in human asthmatic airway smooth muscle cells.

    Directory of Open Access Journals (Sweden)

    Aihua Hu

    Full Text Available Signaling by the Gβγ subunit of Gi protein, leading to downstream c-Src-induced activation of the Ras/c-Raf1/MEK-ERK1/2 signaling pathway and its upregulation of phosphodiesterase-4 (PDE4 activity, was recently shown to mediate the heightened contractility in proasthmatic sensitized isolated airway smooth muscle (ASM, as well as allergen-induced airway hyperresponsiveness and inflammation in an in vivo animal model of allergic asthma. This study investigated whether cultured human ASM (HASM cells derived from asthmatic donor lungs exhibit constitutively increased PDE activity that is attributed to intrinsically upregulated Gβγ signaling coupled to c-Src activation of the Ras/MEK/ERK1/2 cascade. We show that, relative to normal cells, asthmatic HASM cells constitutively exhibit markedly increased intrinsic PDE4 activity coupled to heightened Gβγ-regulated phosphorylation of c-Src and ERK1/2, and direct co-localization of the latter with the PDE4D isoform. These signaling events and their induction of heightened PDE activity are acutely suppressed by treating asthmatic HASM cells with a Gβγ inhibitor. Importantly, along with increased Gβγ activation, asthmatic HASM cells also exhibit constitutively increased direct binding of the small Rap1 GTPase-activating protein, Rap1GAP, to the α-subunit of Gi protein, which serves to cooperatively facilitate Ras activation and, thereby, enable enhanced Gβγ-regulated ERK1/2-stimulated PDE activity. Collectively, these data are the first to identify that intrinsically increased signaling via the Gβγ subunit, facilitated by Rap1GAP recruitment to the α-subunit, mediates the constitutively increased PDE4 activity detected in asthmatic HASM cells. These new findings support the notion that interventions targeted at suppressing Gβγ signaling may lead to novel approaches to treat asthma.

  13. Recreational Use of Phosphodiesterase 5 Inhibitors and Its Associated Factors among Undergraduate Male Students in an Ethiopian University: A Cross-Sectional Study

    Directory of Open Access Journals (Sweden)

    Eyob Alemayehu Gebreyohannes

    2016-12-01

    Full Text Available Purpose: To assess the prevalence of phosphodiesterase 5 (PDE5 inhibitor use and associated factors among University of Gondar undergraduate students. Materials and Methods: An institution-based, cross-sectional study, using a survey questionnaire, was conducted from October to December 2015 to assess PDE5 inhibitor use and associated factors among male students at the University of Gondar. A Self-Esteem and Relationship questionnaire (14 items, an International Index of Erectile Function questionnaire (15 items and a questionnaire on PDE5 inhibitor use (14 items were included in the survey. Results: Across all respondents (age, 21.9±1.88 years, more than half (55.7%, n=233 had heard about PDE5 inhibitors, but only 23 men (5.5% reported trying a PDE5 inhibitor drug at least once. Older students were more likely to use PDE5 inhibitors compared to younger students (adjusted odds ratio [AOR], 1.40; 95% confidence interval [CI], 1.109∼1.768. Those students who were smokers were 5.15 times more likely to use PDE5 inhibitors as compared to their non-smoking counterparts (AOR, 5.15; 95% CI, 2.096∼12.687. In addition, multivariate logistic regression showed that being in a relationship, alcohol use, greater number of cigarettes smoked per day, and more sexual partners were significantly associated with PDE5 inhibitor use. Conclusions: The prevalence of PDE5 inhibitor use among undergraduate students was 5.5%. Cigarette smoking and other substance use, older age, and greater number of sexual partners were significantly associated factors for PDE5 inhibitor use. These findings suggest that restricting access to PDE5 inhibitor drugs is essential to curtailing misuse among university students.

  14. Cows are not mice: the role of cyclic AMP, phosphodiesterases, and adenosine monophosphate-activated protein kinase in the maintenance of meiotic arrest in bovine oocytes.

    Science.gov (United States)

    Bilodeau-Goeseels, Sylvie

    2011-01-01

    Meiotic maturation in mammalian oocytes is initiated during fetal development, and is then arrested at the dictyate stage - possibly for several years. Oocyte meiosis resumes in preovulatory follicles in response to the lutenizing hormone (LH) surge or spontaneously when competent oocytes are removed from follicles and cultured. The mechanisms involved in meiotic arrest and resumption in bovine oocytes are not fully understood, and several studies point to important differences between oocytes from rodent and livestock species. This paper reviews earlier and contemporary studies on the effects of cAMP-elevating agents and phosphodiesterase (PDE) enzyme inhibitors on the maintenance of meiotic arrest in bovine oocytes in vitro. Contrary to results obtained with mouse oocytes, bovine oocyte meiosis is inhibited by activators of the energy sensor adenosine monophosphate-activated protein kinase (AMPK, mammalian gene PRKA), which is activated by AMP, the degradation product of cAMP. It is not clear whether or not the effects were due to AMPK activation, and they may depend on culture conditions. Evidence suggests that other signaling pathways (for example, the cGMP/nitric oxide pathway) are involved in bovine oocyte meiotic arrest, but further studies are needed to understand the interactions between the signaling pathways that lead to maturation promoting factor (MPF) being inactive or active. An improved understanding of the mechanisms involved in the control of bovine oocyte meiosis will facilitate better control of the process in vitro, resulting in increased developmental competence and increased efficiency of in vitro embryo production procedures. Copyright © 2011 Wiley Periodicals, Inc.

  15. cGMP inhibition of type 3 phosphodiesterase is the major mechanism by which C-type natriuretic peptide activates CFTR in the shark rectal gland

    Science.gov (United States)

    De Jonge, Hugo R.; Tilly, Ben C.; Hogema, Boris M.; Pfau, Daniel J.; Kelley, Catherine A.; Kelley, Megan H.; Melita, August M.; Morris, Montana T.; Viola, Ryan M.

    2013-01-01

    The in vitro perfused rectal gland of the dogfish shark (Squalus acanthias) and filter-grown monolayers of primary cultures of shark rectal gland (SRG) epithelial cells were used to analyze the signal transduction pathway by which C-type natriuretic peptide (CNP) stimulates chloride secretion. CNP binds to natriuretic receptors in the basolateral membrane, elevates cellular cGMP, and opens cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels in the apical membrane. CNP-provoked chloride secretion was completely inhibitable by the nonspecific protein kinase inhibitor staurosporine and the PKA inhibitor H89 but insensitive to H8, an inhibitor of type I and II isoforms of cGMP-dependent protein kinase (cGKI and cGKII). CNP-induced secretion could not be mimicked by nonhydrolyzable cGMP analogs added alone or in combination with the protein kinase C activator phorbolester, arguing against a role for cGK or for cGMP-induced PKC signaling. We failed to detect a dogfish ortholog of cGKII by molecular cloning and affinity chromatography. However, inhibitors of the cGMP-inhibitable isoform of phosphodiesterase (PDE3) including milrinone, amrinone, and cilostamide but not inhibitors of other PDE isoenzymes mimicked the effect of CNP on chloride secretion in perfused glands and monolayers. CNP raised cGMP and cAMP levels in the SRG epithelial cells. This rise in cAMP as well as the CNP and amrinone-provoked chloride secretion, but not the rise in cGMP, was almost completely blocked by the Gαi-coupled adenylyl cyclase inhibitor somatostatin, arguing against a role for cGMP cross-activation of PKA in CNP action. These data provide molecular, functional, and pharmacological evidence for a CNP/cGMP/PDE3/cAMP/PKA signaling cascade coupled to CFTR in the SRG. PMID:24259420

  16. Phosphodiesterase 2A Inhibitor TAK-915 Ameliorates Cognitive Impairments and Social Withdrawal in N-Methyl-d-Aspartate Receptor Antagonist-Induced Rat Models of Schizophrenia.

    Science.gov (United States)

    Nakashima, Masato; Imada, Haruka; Shiraishi, Eri; Ito, Yuki; Suzuki, Noriko; Miyamoto, Maki; Taniguchi, Takahiko; Iwashita, Hiroki

    2018-04-01

    The pathophysiology of schizophrenia has been associated with glutamatergic dysfunction. Modulation of the glutamatergic signaling pathway, including N -methyl-d-aspartate (NMDA) receptors, can provide a new therapeutic target for schizophrenia. Phosphodiesterase 2A (PDE2A) is highly expressed in the forebrain, and is a dual substrate enzyme that hydrolyzes both cAMP and cGMP, which play pivotal roles as intracellular second messengers downstream of NMDA receptors. Here we characterize the in vivo pharmacological profile of a selective and brain-penetrant PDE2A inhibitor, ( N -{(1 S )-1-[3-fluoro-4-(trifluoromethoxy)phenyl]-2-methoxyethyl}-7-methoxy-2-oxo-2,3-dihydropyrido[2,3- b ]pyrazine-4(1 H )-carboxamide) (TAK-915) as a novel treatment of schizophrenia. Oral administration of TAK-915 at 3 and 10 mg/kg significantly increased cGMP levels in the frontal cortex, hippocampus, and striatum of rats. TAK-915 at 10 mg/kg significantly upregulated the phosphorylation of α -amino-3-hydroxy-5-methylisoxazole-4-proprionic acid receptor subunit GluR1 in the rat hippocampus. TAK-915 at 3 and 10 mg/kg significantly attenuated episodic memory deficits induced by the NMDA receptor antagonist (+)-MK-801 hydrogen maleate (MK-801) in the rat passive avoidance test. TAK-915 at 10 mg/kg significantly attenuated working memory deficits induced by MK-801 in the rat radial arm maze test. Additionally, TAK-915 at 10 mg/kg prevented subchronic phencyclidine-induced social withdrawal in social interaction in rats. In contrast, TAK-915 did not produce antipsychotic-like activity; TAK-915 had little effect on MK-801- or methamphetamine-induced hyperlocomotion in rats. These results suggest that TAK-915 has a potential to ameliorate cognitive impairments and social withdrawal in schizophrenia. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

  17. Molecular properties of mammalian proteins that interact with cGMP: protein kinases, cation channels, phosphodiesterases, and multi-drug anion transporters.

    Science.gov (United States)

    Francis, Sharron H; Blount, Mitsi A; Zoraghi, Roya; Corbin, Jackie D

    2005-09-01

    Cyclic GMP is a critical second messenger signaling molecule in many mammalian cell types. It is synthesized by a family of guanylyl cyclases that is activated in response to stimuli from hormones such as natriuretic peptides, members of the guanylin family, and chemical stimuli including nitric oxide and carbon monoxide. The resulting elevation of cGMP modulates myriad physiological processes. Three major groups of cellular proteins bind cGMP specifically at allosteric sites; interaction of cGMP with these sites modulates the activities and functions of other domains within these protein groups to bring about physiological effects. These proteins include the cyclic nucleotide (cN)-dependent protein kinases, cN-gated cation channels, and cGMP-binding phosphodiesterases (PDE). Cyclic GMP also interacts with the catalytic sites of many cN PDEs and with some members of the multi-drug anion transporter family (MRPs) which can extrude nucleotides from cells. The allosteric cN-binding sites in the kinases and the cN-gated channels are evolutionarily and biochemically related, whereas the allosteric cGMP-binding sites in PDEs (also known as GAF domains), the catalytic sites of PDEs , and the ligand-binding sites in the MRPs are evolutionarily and biochemically distinct from each other and from those in the kinase and channel families. The sites that interact with cGMP within each of these groups of proteins have unique properties that provide for cGMP binding. Within a given cell, cGMP can potentially interact with members of all these groups of proteins if they are present. The relative abundance and affinities of these various cGMP-binding sites in conjunction with their subcellular compartmentation, proximity to cyclases and PDEs, and post-translational modification contribute importantly in determining the impact of these respective proteins to cGMP signaling within a particular cell.

  18. Recreational Use of Phosphodiesterase 5 Inhibitors and Its Associated Factors among Undergraduate Male Students in an Ethiopian University: A Cross-Sectional Study

    Science.gov (United States)

    Bhagavathula, Akshaya Srikanth; Gebresillassie, Begashaw Melaku; Tefera, Yonas Getaye; Belachew, Sewunet Admasu; Erku, Daniel Asfaw

    2016-01-01

    Purpose To assess the prevalence of phosphodiesterase 5 (PDE5) inhibitor use and associated factors among University of Gondar undergraduate students. Materials and Methods An institution-based, cross-sectional study, using a survey questionnaire, was conducted from October to December 2015 to assess PDE5 inhibitor use and associated factors among male students at the University of Gondar. A Self-Esteem and Relationship questionnaire (14 items), an International Index of Erectile Function questionnaire (15 items) and a questionnaire on PDE5 inhibitor use (14 items) were included in the survey. Results Across all respondents (age, 21.9±1.88 years), more than half (55.7%, n=233) had heard about PDE5 inhibitors, but only 23 men (5.5%) reported trying a PDE5 inhibitor drug at least once. Older students were more likely to use PDE5 inhibitors compared to younger students (adjusted odds ratio [AOR], 1.40; 95% confidence interval [CI], 1.109~1.768). Those students who were smokers were 5.15 times more likely to use PDE5 inhibitors as compared to their non-smoking counterparts (AOR, 5.15; 95% CI, 2.096~12.687). In addition, multivariate logistic regression showed that being in a relationship, alcohol use, greater number of cigarettes smoked per day, and more sexual partners were significantly associated with PDE5 inhibitor use. Conclusions The prevalence of PDE5 inhibitor use among undergraduate students was 5.5%. Cigarette smoking and other substance use, older age, and greater number of sexual partners were significantly associated factors for PDE5 inhibitor use. These findings suggest that restricting access to PDE5 inhibitor drugs is essential to curtailing misuse among university students. PMID:28053948

  19. The Efficacy of Medical Treatment of Peyronie’s Disease: Potassium Para-Aminobenzoate Monotherapy vs. Combination Therapy with Tamoxifen, L-Carnitine, and Phosphodiesterase Type 5 Inhibitor

    Directory of Open Access Journals (Sweden)

    Tae Yong Park

    2016-04-01

    Full Text Available Purpose: This study was designed to evaluate the efficacy of medical treatment of Peyronie’s disease. Materials and Methods: A total of 109 patients with Peyronie’s disease who had been treated from January 2011 to December 2014 were retrospectively reviewed in this study. Forty-four patients (Group 1 were treated with 12 mg of potassium para-aminobenzoate daily. Sixty-five patients (Group 2 were treated with combination therapy: tamoxifen (20 mg and acetyl-L-carnitine (300 mg twice daily in addition to a phosphodiesterase type 5 inhibitor. Ability to perform sexual intercourse, pain during erection, size of plaque, and penile curvature angle were assessed. Results: In Group 1, 30 of 44 patients (68.2% discontinued treatment within 12 weeks, while 5 patients (7.7% in Group 2 discontinued treatment. Pain during erection and plaque size were improved in both groups but showed no statistical difference due to the high dropout rate in Group 1. In both groups, penile curvature was improved, but demonstrated no statistical difference between the treatment groups. However, combination therapy demonstrated a better response rate in patients whose penile curvature angle was less than 30o (44.4% vs. 79.1%, p=0.048. The rate of successful sexual intercourse was significantly higher in Group 2 (42.8% vs. 78.3%, p=0.034. The number of patients who underwent surgical correction despite medical treatment was significantly higher in Group 1 (35.7% vs. 13.3%, p=0.048. Conclusions: Early medical combination therapy in Peyronie’s disease may present better results in patients whose curvature angle is less than 30o.

  20. Effect of the phosphodiesterase 4 inhibitor roflumilast on glucose metabolism in patients with treatment-naive, newly diagnosed type 2 diabetes mellitus.

    Science.gov (United States)

    Wouters, E F M; Bredenbröker, D; Teichmann, P; Brose, M; Rabe, K F; Fabbri, L M; Göke, B

    2012-09-01

    The phosphodiesterase 4 inhibitor roflumilast is a first-in-class antiinflammatory treatment for severe chronic obstructive pulmonary disease (COPD) associated with chronic bronchitis and a history of frequent exacerbations. In previous clinical studies, a transient and reversible weight decrease was reported with roflumilast, suggesting the systemic actions of this drug may impact metabolism. Our objective was to investigate the effects of roflumilast on glucose homeostasis and body weight. We conducted a 12-wk, randomized, double-blind, placebo-controlled multicenter study with outpatients. Patients (n = 205) with newly diagnosed type 2 diabetes mellitus (DM2) but without COPD were included in the study. Roflumilast 500 μg or placebo was administered once daily. We evaluated mean change in blood glycated hemoglobin levels. We also evaluated mean change from baseline in the postmeal area under the curve (AUC) for a range of metabolic parameters. Roflumilast was associated with a significantly greater reduction in glycated hemoglobin levels than placebo (least square mean = -0.45%; P AUC decreased significantly from baseline to last visit for free fatty acids, glycerol, glucose, and glucagon, whereas they slightly increased for C-peptide and insulin. In contrast to roflumilast, the glucagon AUC increased with placebo, and the insulin AUC decreased. Between-treatment analysis revealed statistically significant differences in favor of roflumilast for glucose (P = 0.0082), glycerol (P = 0.0104), and C-peptide levels (P = 0.0033). Patients in both treatment groups lost weight, although the between-treatment difference of the changes from baseline to last visit [-0.7 (0.4) kg] was not statistically significant (P = 0.0584). Roflumilast lowered glucose levels in patients with newly diagnosed DM2 without COPD, suggesting positive effects on glucose homoeostasis.

  1. Protective effects of phosphodiesterase 2 inhibitor on depression- and anxiety-like behaviors: involvement of antioxidant and anti-apoptotic mechanisms.

    Science.gov (United States)

    Ding, Lianshu; Zhang, Chong; Masood, Anbrin; Li, Jianxin; Sun, Jiao; Nadeem, Ahmed; Zhang, Han-Ting; O' Donnell, James M; Xu, Ying

    2014-07-15

    Stress occurs in everyday life, but the relationship between stress and the onset or development of depression/anxiety remains unknown. Increasing evidence suggests that the impairment of antioxidant defense and the neuronal cell death are important in the process of emotional disorders. Chronic stress impairs the homeostasis of antioxidants/oxidation, which results in the aberrant stimulation of the cell cycle proteins where cGMP-PKG signaling is thought to have an inhibitory role. Phosphodiesterase 2 (PDE2) is linked to cGMP-PKG signaling and highly expressed in the limbic brain regions including hippocampus and amygdala, which may play important roles in the treatment of depression and anxiety. To address the possible effects of PDE2 inhibitors on depression-/anxiety-like behaviors and the underlying mechanisms, Bay 60-7550 (0.75, 1.5 and 3 mg/kg, i.p.) was administered 30 min before chronic stress. The results suggested that Bay 60-7550 not only restored the behavioral changes but also regulated Cu/Zn superoxide dismutase (SOD) levels differentially in hippocampus and amygdala, which were increased in the hippocampus while decreased in the amygdala. It was also significant that Bay 60-7550 regulated the abnormalities of pro- and anti-apoptotic components, such as Bax, Caspase 3 and Bcl-2, and the indicator of PKG signaling characterized by pVASP(ser239), in these two brain regions. The results suggested that Bay 60-7550 is able to alleviate oxidative stress and mediate part of the apoptotic machinery in neuronal cells possibly through SOD-cGMP/PKG-anti-apoptosis signaling and that inhibition of PDE2 may represent a novel therapeutic target for psychiatric disorders, such as depression and anxiety. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Angiotensin II increases phosphodiesterase 5A expression in vascular smooth muscle cells: A mechanism by which angiotensin II antagonizes cGMP signaling

    Science.gov (United States)

    Kim, Dongsoo; Aizawa, Toru; Wei, Heng; Pi, Xinchun; Rybalkin, Sergei D.; Berk, Bradford C.; Yan, Chen

    2014-01-01

    Angiotensin II (Ang II) and nitric oxide (NO)/natriuretic peptide (NP) signaling pathways mutually regulate each other. Imbalance of Ang II and NO/NP has been implicated in the pathophysiology of many vascular diseases. cGMP functions as a key mediator in the interaction between Ang II and NO/NP. Cyclic nucleotide phosphodiesterase 5A (PDE5A) is important in modulating cGMP signaling by hydrolyzing cGMP in vascular smooth muscle cells (VSMC). Therefore, we examined whether Ang II negatively modulates intracellular cGMP signaling in VSMC by regulating PDE5A. Ang II rapidly and transiently increased PDE5A mRNA levels in rat aortic VSMC. Upregulation of PDE5A mRNA was associated with a time-dependent increase of both PDE5 protein expression and activity. Increased PDE5A mRNA level was transcription-dependent and mediated by the Ang II type 1 receptor. Ang II-mediated activation of extracellular signal-regulated kinases 1/2 (ERK1/2) was essential for Ang II-induced PDE5A upregulation. Pretreatment of VSMC with Ang II inhibited C-type NP (CNP) stimulated cGMP signaling, such as cGMP dependent protein kinase (PKG)-mediated phosphorylation of vasodilator-stimulated-phosphoprotein (VASP). Ang II-mediated inhibition of PKG was blocked when PDE5 activity was decreased by selective PDE5 inhibitors, suggesting that upregulation of PDE5A expression is an important mechanism for Ang II to attenuate cGMP signaling. PDE5A may also play a critical role in the growth promoting effects of Ang II because inhibition of PDE5A activity significantly decreased Ang II-stimulated VSMC growth. These observations establish a new mechanism by which Ang II antagonizes cGMP signaling and stimulates VSMC growth. PMID:15623434

  3. Phosphodiesterase-9 (PDE9) inhibition with BAY 73-6691 increases corpus cavernosum relaxations mediated by nitric oxide-cyclic GMP pathway in mice.

    Science.gov (United States)

    da Silva, F H; Pereira, M N; Franco-Penteado, C F; De Nucci, G; Antunes, E; Claudino, M A

    2013-01-01

    Phosphodiesterase-9 (PDE9) specifically hydrolyzes cyclic GMP, and was detected in human corpus cavernosum. However, no previous studies explored the selective PDE9 inhibition with BAY 73-6691 in corpus cavernosum relaxations. Therefore, this study aimed to characterize the PDE9 mRNA expression in mice corpus cavernosum, and investigate the effects of BAY 73-6691 in endothelium-dependent and -independent relaxations, along with the nitrergic corpus cavernosum relaxations. Male mice received daily gavage of BAY 73-6691 (or dimethylsulfoxide) at 3 mg kg(-1) per day for 21 days. Relaxant responses to acetylcholine (ACh), nitric oxide (NO) (as acidified sodium nitrite; NaNO2 solution), sildenafil and electrical-field stimulation (EFS) were obtained in corpus cavernosum in control and BAY 73-6691-treated mice. BAY 73-6691 was also added in vitro 30 min before construction of concentration-responses and frequency curves. PDE9A and PDE5 mRNA expression was detected in the mice corpus cavernosum in a similar manner. In vitro addition of BAY 73-6691 neither itself relaxed mice corpus cavernosum nor changed the NaNO2, sildenafil and EFS-induced relaxations. However, in mice treated chronically with BAY 73-6691, the potency (pEC50) values for ACh, NaNO2 and sildenafil were significantly greater compared with control group. The maximal responses (Emax) to NaNO2 and sildenafil were also significantly greater in BAY 73-6691-treated mice. BAY 73-6691 treatment also significantly increased the magnitude and duration of the nitrergic corpus cavernosum relaxations (8-32 Hz). In conclusion, murine corpus cavernosum expresses PDE9 mRNA. Prolonged PDE9 inhibition with BAY 73-6691 amplifies the NO-cGMP-mediated cavernosal responses, and may be of therapeutic value for erectile dysfunction.

  4. The Global Online Sexuality Survey (GOSS): the United States of America in 2011 chapter II: phosphodiesterase inhibitors utilization among English speakers.

    Science.gov (United States)

    Shaeer, Osama

    2013-02-01

    Utility of phosphodiesterase inhibitors (PDEi's) for the treatment of erectile dysfunction (ED) has been the focus of experimental and clinical studies. However, public preferences, attitudes, and experiences with PDEi's are rarely addressed from a population/epidemiology viewpoint. The Global Online Sexuality Survey (GOSS) is a worldwide epidemiologic study of sexuality and sexual disorders, first launched in the Middle East in 2010, followed by the United States in 2011. To describe the utilization rates, trends, and attitudes toward PDEi's in the United States in the year 2011. GOSS was randomly deployed to English-speaking male Web surfers in the United States via paid advertising on Facebook®, comprising 146 questions. Utilization rates and preferences for PDEi's by brand. Six hundred three subjects participated; mean age 53.43 years ± 13.9. Twenty-three point seven percent used PDEi's on more consistent basis, 37.5% of those with ED vs. 15.6% of those without ED (recreational users). Unrealistic safety concerns including habituation were pronounced. Seventy-nine point six percent of utilization was on prescription basis. PDEi's were purchased through pharmacies (5.3% without prescription) and in 16.5% over the Internet (68% without prescription). Nine point six percent nonprescription users suffered coronary heart disease. Prescription use was inclined toward sildenafil, generally, and particularly in severe cases, and shifted toward tadalafil in moderate ED and for recreational use, followed by vardenafil. Nonprescription utilization trends were similar, except in recreational use where sildenafil came first. In the United States unrealistic safety concerns over PDEi's utility exist and should be addressed. Preference for particular PDEi's over the others is primarily dictated by health-care providers, despite lack of guidelines that govern physician choice. Online and over-the-counter sales of PDEi's are common, and can expose a subset of users to health

  5. Analysis of Pseudomonas aeruginosa diguanylate cyclases and phosphodiesterases reveals a role for bis-(3′-5′)-cyclic-GMP in virulence

    Science.gov (United States)

    Kulesekara, Hemantha; Lee, Vincent; Brencic, Anja; Liberati, Nicole; Urbach, Jonathan; Miyata, Sachiko; Lee, Daniel G.; Neely, Alice N.; Hyodo, Mamoru; Hayakawa, Yoshihiro; Ausubel, Frederick M.; Lory, Stephen

    2006-01-01

    The opportunistic pathogen Pseudomonas aeruginosa is responsible for systemic infections in immunocompromised individuals and chronic respiratory disease in patients with cystic fibrosis. Cyclic nucleotides are known to play a variety of roles in the regulation of virulence-related factors in pathogenic bacteria. A set of P. aeruginosa genes, encoding proteins that contain putative domains characteristic of diguanylate cyclases (DGCs) and phosphodiesterases (PDEs) that are responsible for the maintenance of cellular levels of the second messenger bis-(3′-5′)-cyclic dimeric GMP (c-di-GMP) was identified in the annotated genomes of P. aeruginosa strains PAO1 and PA14. Although the majority of these genes are components of the P. aeruginosa core genome, several are located on presumptive horizontally acquired genomic islands. A comprehensive analysis of P. aeruginosa genes encoding the enzymes of c-di-GMP metabolism (DGC- and PDE-encoding genes) was carried out to analyze the function of c-di-GMP in two disease-related phenomena, cytotoxicity and biofilm formation. Analysis of the phenotypes of DGC and PDE mutants and overexpressing clones revealed that certain virulence-associated traits are controlled by multiple DGCs and PDEs through alterations in c-di-GMP levels. A set of mutants in selected DGC- and PDE-encoding genes exhibited attenuated virulence in a mouse infection model. Given that insertions in different DGC and PDE genes result in distinct phenotypes, it seems likely that the formation or degradation of c-di-GMP by these enzymes is in highly localized and intimately linked to particular targets of c-di-GMP action. PMID:16477007

  6. Phosphodiesterase inhibition mediates matrix metalloproteinase activity and the level of collagen degradation fragments in a liver fibrosis ex vivo rat model

    Directory of Open Access Journals (Sweden)

    Veidal Sanne Skovgård

    2012-12-01

    Full Text Available Abstract Background Accumulation of extracellular matrix (ECM and increased matrix metalloproteinase (MMP activity are hallmarks of liver fibrosis. The aim of the present study was to develop a model of liver fibrosis combining ex vivo tissue culture of livers from CCl4 treated animals with an ELISA detecting a fragment of type III collagen generated in vitro by MMP-9 (C3M, known to be associated with liver fibrosis and to investigate cAMP modulation of MMP activity and liver tissue turnover in this model. Findings In vivo: Rats were treated for 8 weeks with CCl4/Intralipid. Liver slices were cultured for 48 hours. Levels of C3M were determined in the supernatants of slices cultured without treatment, treated with GM6001 (positive control or treated with IBMX (phosphodiesterase inhibitor. Enzymatic activity of MMP-2 and MMP-9 were studied by gelatin zymography. Ex vivo: The levels of serum C3M increased 77% in the CCl4-treated rats at week 8 (p 4-treated animals had highly increased MMP-9, but not MMP-2 activity, compared to slices derived from control animals. Conclusions We have combined an ex vivo model of liver fibrosis with measurement of a biochemical marker of collagen degradation in the condition medium. This technology may be used to evaluate the molecular process leading to structural fibrotic changes, as collagen species are the predominant structural part of fibrosis. These data suggest that modulation of cAMP may play a role in regulation of collagen degradation associated with liver fibrosis.

  7. Lipolytic effect of a polyphenolic citrus dry extract of red orange, grapefruit, orange (SINETROL) in human body fat adipocytes. Mechanism of action by inhibition of cAMP-phosphodiesterase (PDE).

    Science.gov (United States)

    Dallas, Constantin; Gerbi, Alain; Tenca, Guillaume; Juchaux, Franck; Bernard, François-Xavier

    2008-10-01

    The present study investigated the lipolytic (break of fat stored) effect of a citrus-based polyphenolic dietary supplement (SINETROL) at human adipocytes (ex vivo), body fat (clinical) and biochemical levels (inhibition of phosphodiesterase). Free fatty acids (FFA) release was used as indicator of human adipocyte lipolysis and SINETROL activity has been compared with known lipolytic products (isoproterenol, theopylline and caffeine). SINETROL stimulated significantly the lipolytic activity in a range of 6 fold greater than the control. Moreover, SINETROL has 2.1 greater activity than guarana 12% caffeine while its content in caffeine is 3 times lower. Clinically, two groups of 10 volunteers with BMI relevant of overweight were compared during 4 and 12 weeks with 1.4 g/day SINETROL and placebo supplementation. In the SINETROL Group the body fat (%) decreased with a significant difference of 5.53% and 15.6% after 4 and 12 weeks, respectively, while the body weight (kg) decreased with a significant difference of 2.2 and 5.2 kg after 4 and 12 weeks, respectively. These observed effects are linked to SINETROL polyphenolic composition and its resulting synergistic activity. SINETROL is a potent inhibitor of cAMP-phosphodiesterase (PDE) (97%) compared to other purified compounds (cyanidin-3 glycoside, narangin, caffeine). These results suggest that SINETROL has a strong lipolytic effect mediated by cAMP-PDE inhibition. SINETROL may serve to prevent obesity by decreasing BMI.

  8. Characterization of ["1"1C]Lu AE92686 as a PET radioligand for phosphodiesterase 10A in the nonhuman primate brain

    International Nuclear Information System (INIS)

    Yang, Kai-Chun; Stepanov, Vladimir; Amini, Nahid; Martinsson, Stefan; Takano, Akihiro; Halldin, Christer; Nielsen, Jacob; Bundgaard, Christoffer; Bang-Andersen, Benny; Grimwood, Sarah; Farde, Lars; Finnema, Sjoerd J.

    2017-01-01

    ["1"1C]Lu AE92686 is a positron emission tomography (PET) radioligand that has recently been validated for examining phosphodiesterase 10A (PDE10A) in the human striatum. ["1"1C]Lu AE92686 has high affinity for PDE10A (IC_5_0 = 0.39 nM) and may also be suitable for examination of the substantia nigra, a region with low density of PDE10A. Here, we report characterization of regional ["1"1C]Lu AE92686 binding to PDE10A in the nonhuman primate (NHP) brain. A total of 11 PET measurements, seven baseline and four following pretreatment with unlabeled Lu AE92686 or the structurally unrelated PDE10A inhibitor MP-10, were performed in five NHPs using a high resolution research tomograph (HRRT). ["1"1C]Lu AE92686 binding was quantified using a radiometabolite-corrected arterial input function and compartmental and graphical modeling approaches. Regional time-activity curves were best described with the two-tissue compartment model (2TCM). However, the distribution volume (V_T) values for all regions were obtained by the Logan plot analysis, as reliable cerebellar V_T values could not be derived by the 2TCM. For cerebellum, a proposed reference region, V_T values increased by ∝30 % with increasing PET measurement duration from 63 to 123 min, while V_T values in target regions remained stable. Both pretreatment drugs significantly decreased ["1"1C]Lu AE92686 binding in target regions, while no significant effect on cerebellum was observed. Binding potential (BP_N_D) values, derived with the simplified reference tissue model (SRTM), were 13-17 in putamen and 3-5 in substantia nigra and correlated well to values from the Logan plot analysis. The method proposed for quantification of ["1"1C]Lu AE92686 binding in applied studies in NHP is based on 63 min PET data and SRTM with cerebellum as a reference region. The study supports that ["1"1C]Lu AE92686 can be used for PET examinations of PDE10A binding also in substantia nigra. (orig.)

  9. Radiosynthesis and in vivo evaluation of [{sup 11}C]MP-10 as a positron emission tomography radioligand for phosphodiesterase 10A

    Energy Technology Data Exchange (ETDEWEB)

    Plisson, Christophe, E-mail: Christophe.2.plisson@gsk.com [GlaxoSmithKline, Clinical Imaging Centre Hammersmith Hospital, London, W12 0NN (United Kingdom); Salinas, Cristian [GlaxoSmithKline, Clinical Imaging Centre Hammersmith Hospital, London, W12 0NN (United Kingdom); Weinzimmer, David; Labaree, David; Lin, Shu-Fei; Ding, Yu-Shin [Yale University PET Center, Yale University School of Medicine, PO Box 208048 New Haven, CT (United States); Jakobsen, Steen [Aarhus PET Centre, Aarhus Sygehus, Norrebrogade 44, DK-8000 Aarhus C (Denmark); Smith, Paul W. [GlaxoSmithKline, Clinical Imaging Centre Hammersmith Hospital, London, W12 0NN (United Kingdom); Eiji, Kawanishi [Medicinal Chemistry Research Laboratories II, Research Division, Mitsubishi Tanabe Pharma Corporation, Saitama 335-8505 (Japan); Carson, Richard E. [Yale University PET Center, Yale University School of Medicine, PO Box 208048 New Haven, CT (United States); Gunn, Roger N.; Rabiner, Eugenii A. [GlaxoSmithKline, Clinical Imaging Centre Hammersmith Hospital, London, W12 0NN (United Kingdom)

    2011-08-15

    Introduction: The aim of this study was to evaluate a newly reported positron emission tomography (PET) radioligand [{sup 11}C]MP-10, a potent and selective inhibitor of the central phosphodiesterase 10A enzyme (PDE10A) in vivo, using PET. Methods: A procedure was developed for labeling MP-10 with carbon-11. [{sup 11}C]MP-10 was evaluated in vivo both in the pig and baboon brain. Results: Alkylation of the corresponding desmethyl compound with [{sup 11}C]methyl iodide produced [{sup 11}C]MP-10 with good radiochemical yield and specific activity. PET studies in the pig showed that [{sup 11}C]MP-10 rapidly entered the brain reaching peak tissue concentration at 1-2 min postadministration, followed by washout from the tissue. Administration of a selective PDE10A inhibitor reduced the binding in all brain regions to the levels of the cerebellum, demonstrating the saturability and selectivity of [{sup 11}C]MP-10 binding. In the nonhuman primate, the brain tissue kinetics of [{sup 11}C]MP-10 were slower, reaching peak tissue concentrations at 30-60 min postadministration. In both species, the observed rank order of regional brain signal was striatum>diencephalon>cortical regions=cerebellum, consistent with the known distribution and concentration of PDE10A. [{sup 11}C]MP-10 brain kinetics were well described by a two-tissue compartment model, and estimates of total volume of distribution (V{sub T}) were obtained. Blocking studies with unlabeled MP-10 revealed the suitability of the cerebellum as a reference tissue and enabled the estimation of regional binding potential (BP{sub ND}) as the outcome measure of specific binding. Quantification of [{sup 11}C]MP-10 binding using the simplified reference tissue model with cerebellar input function produced BP{sub ND} estimates consistent with those obtained by the two-tissue compartment model. Conclusion: We demonstrated that [{sup 11}C]MP-10 possesses good characteristics for the in vivo quantification of the PDE10A in the

  10. Inhibition of Phosphodiesterase 4 by FCPR03 Alleviates Lipopolysaccharide-Induced Depressive-Like Behaviors in Mice: Involvement of p38 and JNK Signaling Pathways

    Directory of Open Access Journals (Sweden)

    Hui Yu

    2018-02-01

    Full Text Available Inflammatory responses induced by peripheral administration of lipopolysaccharide (LPS triggers depressive-like behavioral syndrome in rodents. Inhibition of phosphodiesterase 4 (PDE4 produces a robust anti-inflammatory effect in inflammatory cells. Unfortunately, archetypal PDE4 inhibitors cause intolerable gastrointestinal side-effects, such as vomiting and nausea. N-isopropyl-3-(cyclopropylmethoxy-4-difluoromethoxy benzamide (FCPR03 is a novel, selective PDE4 inhibitor with little, or no, emetic potency. Our previous studies show that FCPR03 is effective in attenuating neuroinflammation in mice treated with LPS. However, whether FCPR03 could exert antidepressant-like effect induced by LPS is largely unknown. In the present study, mice injected intraperitoneally (i.p. with LPS was established as an in vivo animal model of depression. The antidepressant-like activities of FCPR03 were evaluated using a tail suspension test, forced swimming test, and sucrose preference test. We demonstrated that administration of FCPR03 (1 mg/kg produced antidepressant-like effects in mice challenged by LPS, as evidenced by decreases in the duration of immobility in the forced swim and tail suspension tests, while no significant changes in locomotor activity were observed. FCPR03 also increased sucrose preference in mice treated with LPS. In addition, treatment with FCPR03 abolished the downregulation of brain-derived neurotrophic factor induced by LPS and decreased the level of corticosterone in plasma. Meanwhile, periphery immune challenge by LPS induced enhanced phosphorylation of p38-mitogen activated protein kinase (p38 and c-Jun N-terminal kinase (JNK in both the cerebral cortex and hippocampus in mice. Interestingly, treatment with FCPR03 significantly blocked the role of LPS and reduced the levels of phosphorylated p38 and JNK. Collectively, these results indicate that FCPR03 shows antidepressant-like effects in mice challenged by LPS, and the p38/JNK

  11. Improvement of spatial memory function in APPswe/PS1dE9 mice after chronic inhibition of phosphodiesterase type 4D.

    Science.gov (United States)

    Sierksma, A S R; van den Hove, D L A; Pfau, F; Philippens, M; Bruno, O; Fedele, E; Ricciarelli, R; Steinbusch, H W M; Vanmierlo, T; Prickaerts, J

    2014-02-01

    Phosphodiesterase type 4 inhibitors (PDE4-Is) have received increasing attention as cognition-enhancers and putative treatment strategies for Alzheimer's disease (AD). By preventing cAMP breakdown, PDE4-Is can enhance intracellular signal transduction and increase the phosphorylation of cAMP response element-binding protein (CREB) and transcription of proteins related to synaptic plasticity and associated memory formation. Unfortunately, clinical development of PDE4-Is has been seriously hampered by emetic side effects. The new isoform-specific PDE4D-I, GEBR-7b, has shown to have beneficial effects on memory at non-emetic doses. The aim of the current study was to investigate chronic cognition-enhancing effects of GEBR-7b in a mouse model of AD. To this extent, 5-month-old (5M) APPswe/PS1dE9 mice received daily subcutaneous injections with GEBR-7b (0.001 mg/kg) or vehicle for a period of 3 weeks, and were tested on affective and cognitive behavior at 7M. We demonstrated a cognition-enhancing potential in APPswe/PS1dE9 mice as their spatial memory function at 7M in the object location test was improved by prior GEBR-7b treatment. APPswe/PS1dE9 mice displayed lower levels of CREB phosphorylation, which remained unaltered after chronic GEBR-7b treatment, and higher levels of tau in the hippocampus. Hippocampal brain-derived neurotrophic factor levels and synaptic densities were not different between experimental groups and no effects were observed on hippocampal GSK3β and tau phosphorylation or Aβ levels. In conclusion, GEBR-7b can enhance spatial memory function in the APPswe/PS1dE9 mouse model of AD. Although the underlying mechanisms of its cognition-enhancing potential remain to be elucidated, PDE4D inhibition appears an interesting novel therapeutic option for cognitive deficits in AD. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. A review of analytical methods for the determination of four new phosphodiesterase type 5 inhibitors in biological samples and pharmaceutical preparations

    Directory of Open Access Journals (Sweden)

    Cristiane Franco Codevilla

    2013-03-01

    Full Text Available The introduction of oral phosphodiesterase type 5 inhibitor therapy in 1998 revolutionized the treatment of erectile dysfunction. Erectile dysfunction is the most common sexual problem in men. It often has a profound effect on intimate relationships and quality of life. The analysis of pharmaceuticals is an important part of the drug development process as well as for routine analysis and quality control of commercial formulations. Whereas the determination of sildenafil citrate, vardenafil and tadalafil are well documented by a variety of methods, there are few publications about the determination of udenafil, lodenafil carbonate, mirodenafil and avanafil. The paper presents a brief review of the action mechanism, adverse effects, pharmacokinetics and the most recent analytical methods that can determine drug concentration in biological matrices and pharmaceutical formulations of these four drugs.A introdução da terapia oral com inibidores da fosfodiesterase tipo 5, em 1998, revolucionou o tratamento da disfunção erétil. A disfunção erétil é o problema sexual mais comum em homens. Muitas vezes tem um efeito profundo nas relações íntimas e na qualidade de vida. A análise de produtos farmacêuticos é uma parte importante do processo de desenvolvimento de fármacos, bem como para a análise de rotina e controle de qualidade das formulações comerciais. Enquanto a determinação do citrato de sildenafila, vardenafila e tadalafila está bem documentada por uma variedade de métodos, existem poucas publicações sobre a determinação de udenafila, carbonato de lodenafila, mirodenafila e avanafila. O artigo apresenta uma breve revisão do mecanismo de ação, efeitos adversos, farmacocinética e os mais recentes métodos analíticos, que podem determinar a concentração do fármaco em matrizes biológicas e formulações farmacêuticas destes quatro fármacos.

  13. Characterization of [{sup 11}C]Lu AE92686 as a PET radioligand for phosphodiesterase 10A in the nonhuman primate brain

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Kai-Chun; Stepanov, Vladimir; Amini, Nahid; Martinsson, Stefan; Takano, Akihiro; Halldin, Christer [Karolinska Institutet, Karolinska University Hospital, Department of Clinical Neuroscience, Center for Psychiatric Research, Stockholm (Sweden); Nielsen, Jacob [H. Lundbeck A/S, Synaptic Transmission, Valby (Denmark); Bundgaard, Christoffer; Bang-Andersen, Benny [H. Lundbeck A/S, Discovery Chemistry and DMPK, Valby (Denmark); Grimwood, Sarah [Pfizer Inc., Neuroscience and Pain Research Unit, Cambridge, MA (United States); Farde, Lars [Karolinska Institutet, Karolinska University Hospital, Department of Clinical Neuroscience, Center for Psychiatric Research, Stockholm (Sweden); AstraZeneca PET Science Center at Karolinska Institutet, Personalized Health Care and Biomarkers, Stockholm (Sweden); Finnema, Sjoerd J. [Karolinska Institutet, Karolinska University Hospital, Department of Clinical Neuroscience, Center for Psychiatric Research, Stockholm (Sweden); Yale University, Department of Radiology and Biomedical Imaging, New Haven, CT (United States)

    2017-02-15

    [{sup 11}C]Lu AE92686 is a positron emission tomography (PET) radioligand that has recently been validated for examining phosphodiesterase 10A (PDE10A) in the human striatum. [{sup 11}C]Lu AE92686 has high affinity for PDE10A (IC{sub 50} = 0.39 nM) and may also be suitable for examination of the substantia nigra, a region with low density of PDE10A. Here, we report characterization of regional [{sup 11}C]Lu AE92686 binding to PDE10A in the nonhuman primate (NHP) brain. A total of 11 PET measurements, seven baseline and four following pretreatment with unlabeled Lu AE92686 or the structurally unrelated PDE10A inhibitor MP-10, were performed in five NHPs using a high resolution research tomograph (HRRT). [{sup 11}C]Lu AE92686 binding was quantified using a radiometabolite-corrected arterial input function and compartmental and graphical modeling approaches. Regional time-activity curves were best described with the two-tissue compartment model (2TCM). However, the distribution volume (V{sub T}) values for all regions were obtained by the Logan plot analysis, as reliable cerebellar V{sub T} values could not be derived by the 2TCM. For cerebellum, a proposed reference region, V{sub T} values increased by ∝30 % with increasing PET measurement duration from 63 to 123 min, while V{sub T} values in target regions remained stable. Both pretreatment drugs significantly decreased [{sup 11}C]Lu AE92686 binding in target regions, while no significant effect on cerebellum was observed. Binding potential (BP{sub ND}) values, derived with the simplified reference tissue model (SRTM), were 13-17 in putamen and 3-5 in substantia nigra and correlated well to values from the Logan plot analysis. The method proposed for quantification of [{sup 11}C]Lu AE92686 binding in applied studies in NHP is based on 63 min PET data and SRTM with cerebellum as a reference region. The study supports that [{sup 11}C]Lu AE92686 can be used for PET examinations of PDE10A binding also in substantia

  14. Inhibition of the striatal specific phosphodiesterase PDE10A ameliorates striatal and cortical pathology in R6/2 mouse model of Huntington's disease.

    Directory of Open Access Journals (Sweden)

    Carmela Giampà

    2010-10-01

    Full Text Available Huntington's disease is a devastating neurodegenerative condition for which there is no therapy to slow disease progression. The particular vulnerability of striatal medium spiny neurons to Huntington's pathology is hypothesized to result from transcriptional dysregulation within the cAMP and CREB signaling cascades in these neurons. To test this hypothesis, and a potential therapeutic approach, we investigated whether inhibition of the striatal-specific cyclic nucleotide phosphodiesterase PDE10A would alleviate neurological deficits and brain pathology in a highly utilized model system, the R6/2 mouse.R6/2 mice were treated with the highly selective PDE10A inhibitor TP-10 from 4 weeks of age until euthanasia. TP-10 treatment significantly reduced and delayed the development of the hind paw clasping response during tail suspension, deficits in rotarod performance, and decrease in locomotor activity in an open field. Treatment prolonged time to loss of righting reflex. These effects of PDE10A inhibition on neurological function were reflected in a significant amelioration in brain pathology, including reduction in striatal and cortical cell loss, the formation of striatal neuronal intranuclear inclusions, and the degree of microglial activation that occurs in response to the mutant huntingtin-induced brain damage. Striatal and cortical levels of phosphorylated CREB and BDNF were significantly elevated.Our findings provide experimental support for targeting the cAMP and CREB signaling pathways and more broadly transcriptional dysregulation as a therapeutic approach to Huntington's disease. It is noteworthy that PDE10A inhibition in the R6/2 mice reduces striatal pathology, consistent with the localization of the enzyme in medium spiny neurons, and also cortical pathology and the formation of neuronal nuclear inclusions. These latter findings suggest that striatal pathology may be a primary driver of these secondary pathological events. More

  15. Phosphodiesterase profile of human B lymphocytes from normal and atopic donors and the effects of PDE inhibition on B cell proliferation

    Science.gov (United States)

    Gantner, Florian; Götz, Christine; Gekeler, Volker; Schudt, Christian; Wendel, Albrecht; Hatzelmann, Armin

    1998-01-01

    CD19+ B lymphocytes were purified from the peripheral blood of normal and atopic subjects to analyse and compare the phosphodiesterase (PDE) activity profile, PDE mRNA expression and the importance of PDE activity for the regulation of B cell function.The majority of cyclic AMP hydrolyzing activity of human B cells was cytosolic PDE4, followed by cytosolic PDE7-like activity; marginal PDE3 activity was found only in the particulate B cell fraction. PDE1, PDE2 and PDE5 activities were not detected.By cDNA-PCR analysis mRNA of the PDE4 subtypes A, B (splice variant PDE4B2) and D were detected. In addition, a weak signal for PDE3A was found.No differences in PDE activities or mRNA expression of PDE subtypes were found in B cells from either normal or atopic subjects.Stimulation of B lymphocytes with the polyclonal stimulus lipopolysaccharide (LPS) induced a proliferative response in a time- and concentration-dependent manner, which was increased in the presence of interleukin-4 (IL-4). PDE4 inhibitors (rolipram, piclamilast) led to an increase in the cellular cyclic AMP concentration and to an augmentation of proliferation, whereas a PDE3 inhibitor (motapizone) was ineffective, which is in accordance with the PDE profile found. The proliferation enhancing effect of the PDE4 inhibitors was partly mimicked by the cyclic AMP analogues dibutyryl (db) cyclic AMP and 5,6-dichloro-1-β-D-ribofuranosylbenzimidazole-3′,5′-cyclic monophosphorothioate, Sp-isomer (dcl-cBIMPS), respectively. However, at concentrations exceeding 100 μM db-cyclic AMP suppressed B lymphocyte proliferation, probably as a result of cytotoxicity. Prostaglandin E2 (PGE2, 1 μM) and forskolin (10 μM) did not affect B cell proliferation, even when given in combination with rolipram.Inhibition of protein kinase A (PKA) by differentially acting selective inhibitors (KT 5720, Rp-8-Br-cyclic AMPS) decreased the proliferative response of control cells and reversed the proliferation enhancing effects

  16. Off-Label Use of Phosphodiesterase Type 5 Inhibitor Erectile Dysfunction Medication to Enhance Sex Among Gay and Bisexual Men in Australia: Results From the FLUX Study.

    Science.gov (United States)

    Hammoud, Mohamed A; Jin, Fengyi; Lea, Toby; Maher, Lisa; Grierson, Jeffrey; Prestage, Garrett

    2017-06-01

    be representative of all GBMs in Australia. GBMs who used an oral EDM in the previous 6 months often used it for recreational purposes, but many of those who used it on a weekly basis also might have used it for therapeutic reasons. GBMs often use EDMs to enhance their sexual experiences often in the context of intensive sex partying (which can include risky sexual behavior). Hammoud MA, Jin F, Lea T, et al. Off-Label Use of Phosphodiesterase Type 5 Inhibitor Erectile Dysfunction Medication to Enhance Sex Among Gay and Bisexual Men in Australia: Results From the FLUX Study. J Sex Med 2017;14:774-784. Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

  17. Luteinizing hormone signaling phosphorylates and activates the cyclic GMP phosphodiesterase PDE5 in mouse ovarian follicles, contributing an additional component to the hormonally induced decrease in cyclic GMP that reinitiates meiosis.

    Science.gov (United States)

    Egbert, Jeremy R; Yee, Siu-Pok; Jaffe, Laurinda A

    2018-03-01

    Prior to birth, oocytes within mammalian ovarian follicles initiate meiosis, but then arrest in prophase until puberty, when with each reproductive cycle, one or more follicles are stimulated by luteinizing hormone (LH) to resume meiosis in preparation for fertilization. Within preovulatory follicles, granulosa cells produce high levels of cGMP, which diffuses into the oocyte to maintain meiotic arrest. LH signaling restarts meiosis by rapidly lowering the levels of cGMP in the follicle and oocyte. Part of this decrease is mediated by the dephosphorylation and inactivation the NPR2 guanylyl cyclase in response to LH, but the mechanism for the remainder of the cGMP decrease is unknown. At least one cGMP phosphodiesterase, PDE5, is activated by LH signaling, which would contribute to lowering cGMP. PDE5 exhibits increased cGMP-hydrolytic activity when phosphorylated on serine 92, and we recently demonstrated that LH signaling phosphorylates PDE5 on this serine and increases its activity in rat follicles. To test the extent to which this mechanism contributes to the cGMP decrease that restarts meiosis, we generated a mouse line in which serine 92 was mutated to alanine (Pde5-S92A), such that it cannot be phosphorylated. Here we show that PDE5 phosphorylation is required for the LH-induced increase in cGMP-hydrolytic activity, but that this increase has only a modest effect on the LH-induced cGMP decrease in mouse follicles, and does not affect the timing of meiotic resumption. Though we show that the activation of PDE5 is among the mechanisms contributing to the cGMP decrease, these results suggest that another cGMP phosphodiesterase is also activated by LH signaling. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Fabrication and evaluation of magnetic phosphodiesterase-5 linked nanoparticles as adsorbent for magnetic dispersive solid-phase extraction of inhibitors from Chinese herbal medicine prior to ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry analysis.

    Science.gov (United States)

    Tao, Yi; Gu, Xianghui; Li, Weidong; Cai, Baochang

    2018-01-12

    In the present study, the preparation of the magnetic phosphodiesterase-5 linked Fe 3 O 4 @ SiO 2 nanoparticles was successfully achieved by amide reaction and the magnetic phosphodiesterase-5 linked Fe 3 O 4 @SiO 2 nanoparticles were evaluated as a new adsorbent for magnetic dispersive solid-phase extraction of ligands from medicinal plant samples before the analysis by UHPLC-Q-TOF/MS. The prepared phosphodiesterase-5 linked Fe 3 O 4 @SiO 2 nanoparticles were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, vibration sample magnetometer and potential laser particle size analyzer. The effects of EDC concentration, incubation time and bead-protein ratio on the amount of immobilized protein were studied. The main experimental parameters affect extraction efficiency of ligands, such as wash times, wash solvents, incubation pH, ion strength and incubation temperature, were investigated and optimized by using echinacoside as a model compound. The absolute recovery of echinacoside was ranged from 98.36%-102.16% in Cistanche tubulosa sample under the optimal extraction conditions. Good linearity was observed in the investigated concentration range of 0.006 mgmL -1 -0.97 mgmL -1 (R 2  = 0.9999). The limit of detection was 0.002 mgmL -1 . The RSDs of within-day and between-day precision were less than 2.3%. Due to the excellent magnetic behavior of Fe 3 O 4 @SiO 2 nanoparticles, the proposed method was shown to be simple and rapid. Remarkably, the magnetic phosphodiesterase-5 linked Fe 3 O 4 @SiO 2 nanoparticles could be recycled for ten times with loss of 10% activity. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. The Seed Repair Response during Germination: Disclosing Correlations between DNA Repair, Antioxidant Response, and Chromatin Remodeling in Medicago truncatula

    Directory of Open Access Journals (Sweden)

    Andrea Pagano

    2017-11-01

    Full Text Available This work provides novel insights into the effects caused by the histone deacetylase inhibitor trichostatin A (TSA during Medicago truncatula seed germination, with emphasis on the seed repair response. Seeds treated with H2O and TSA (10 and 20 μM were collected during imbibition (8 h and at the radicle protrusion phase. Biometric data showed delayed germination and impaired seedling growth in TSA-treated samples. Comet assay, performed on radicles at the protrusion phase and 4-days old M. truncatula seedlings, revealed accumulation of DNA strand breaks upon exposure to TSA. Activation of DNA repair toward TSA-mediated genotoxic damage was evidenced by the up-regulation of MtOGG1(8-OXOGUANINE GLYCOSYLASE/LYASE gene involved in the removal of oxidative DNA lesions, MtLIGIV(LIGASE IV gene, a key determinant of seed quality, required for the rejoining of DNA double strand breaks and TDP(TYROSYL-DNA PHOSPHODIESTERASE genes encoding the multipurpose DNA repair enzymes tyrosyl-DNA phosphodiesterases. Since radical scavenging can prevent DNA damage, the specific antioxidant activity (SAA was measured by DPPH (1,1-diphenyl-2-picrylhydrazyl and Folin-Ciocalteu reagent assays. Fluctuations of SAA were observed in TSA-treated seeds/seedlings concomitant with the up-regulation of antioxidant genes MtSOD(SUPEROXIDE DISMUTASE, MtAPX(ASCORBATE PEROXIDASE and MtMT2(TYPE 2 METALLOTHIONEIN. Chromatin remodeling, required to facilitate the access of DNA repair enzymes at the damaged sites, is also part of the multifaceted seed repair response. To address this aspect, still poorly explored in plants, the MtTRRAP(TRANSFORMATION/TRANSACTIVATION DOMAIN-ASSOCIATED PROTEIN gene was analyzed. TRRAP is a transcriptional adaptor, so far characterized only in human cells where it is needed for the recruitment of histone acetyltransferase complexes to chromatin during DNA repair. The MtTRRAP gene and the predicted interacting partners MtHAM2 (HISTONE ACETYLTRANSFERASE OF

  20. Homology modeling, docking studies and molecular dynamic simulations using graphical processing unit architecture to probe the type-11 phosphodiesterase catalytic site: a computational approach for the rational design of selective inhibitors.

    Science.gov (United States)

    Cichero, Elena; D'Ursi, Pasqualina; Moscatelli, Marco; Bruno, Olga; Orro, Alessandro; Rotolo, Chiara; Milanesi, Luciano; Fossa, Paola

    2013-12-01

    Phosphodiesterase 11 (PDE11) is the latest isoform of the PDEs family to be identified, acting on both cyclic adenosine monophosphate and cyclic guanosine monophosphate. The initial reports of PDE11 found evidence for PDE11 expression in skeletal muscle, prostate, testis, and salivary glands; however, the tissue distribution of PDE11 still remains a topic of active study and some controversy. Given the sequence similarity between PDE11 and PDE5, several PDE5 inhibitors have been shown to cross-react with PDE11. Accordingly, many non-selective inhibitors, such as IBMX, zaprinast, sildenafil, and dipyridamole, have been documented to inhibit PDE11. Only recently, a series of dihydrothieno[3,2-d]pyrimidin-4(3H)-one derivatives proved to be selective toward the PDE11 isoform. In the absence of experimental data about PDE11 X-ray structures, we found interesting to gain a better understanding of the enzyme-inhibitor interactions using in silico simulations. In this work, we describe a computational approach based on homology modeling, docking, and molecular dynamics simulation to derive a predictive 3D model of PDE11. Using a Graphical Processing Unit architecture, it is possible to perform long simulations, find stable interactions involved in the complex, and finally to suggest guideline for the identification and synthesis of potent and selective inhibitors. © 2013 John Wiley & Sons A/S.

  1. Particle swarm optimization and genetic algorithm as feature selection techniques for the QSAR modeling of imidazo[1,5-a]pyrido[3,2-e]pyrazines, inhibitors of phosphodiesterase 10A.

    Science.gov (United States)

    Goodarzi, Mohammad; Saeys, Wouter; Deeb, Omar; Pieters, Sigrid; Vander Heyden, Yvan

    2013-12-01

    Quantitative structure-activity relationship (QSAR) modeling was performed for imidazo[1,5-a]pyrido[3,2-e]pyrazines, which constitute a class of phosphodiesterase 10A inhibitors. Particle swarm optimization (PSO) and genetic algorithm (GA) were used as feature selection techniques to find the most reliable molecular descriptors from a large pool. Modeling of the relationship between the selected descriptors and the pIC50 activity data was achieved by linear [multiple linear regression (MLR)] and non-linear [locally weighted regression (LWR) based on both Euclidean (E) and Mahalanobis (M) distances] methods. In addition, a stepwise MLR model was built using only a limited number of quantum chemical descriptors, selected because of their correlation with the pIC50 . The model was not found interesting. It was concluded that the LWR model, based on the Euclidean distance, applied on the descriptors selected by PSO has the best prediction ability. However, some other models behaved similarly. The root-mean-squared errors of prediction (RMSEP) for the test sets obtained by PSO/MLR, GA/MLR, PSO/LWRE, PSO/LWRM, GA/LWRE, and GA/LWRM models were 0.333, 0.394, 0.313, 0.333, 0.421, and 0.424, respectively. The PSO-selected descriptors resulted in the best prediction models, both linear and non-linear. © 2013 John Wiley & Sons A/S.

  2. Phosphodiesterase inhibitors suppress Lactobacillus casei cell-wall-induced NF-κB and MAPK activations and cell proliferation through protein kinase A--or exchange protein activated by cAMP-dependent signal pathway.

    Science.gov (United States)

    Saito, Takekatsu; Sugimoto, Naotoshi; Ohta, Kunio; Shimizu, Tohru; Ohtani, Kaori; Nakayama, Yuko; Nakamura, Taichi; Hitomi, Yashiaki; Nakamura, Hiroyuki; Koizumi, Shoichi; Yachie, Akihiro

    2012-01-01

    Specific strains of Lactobacillus have been found to be beneficial in treating some types of diarrhea and vaginosis. However, a high mortality rate results from underlying immunosuppressive conditions in patients with Lactobacillus casei bacteremia. Cyclic AMP (cAMP) is a small second messenger molecule that mediates signal transduction. The onset and progression of inflammatory responses are sensitive to changes in steady-state cAMP levels. L. casei cell wall extract (LCWE) develops arteritis in mice through Toll-like receptor-2 signaling. The purpose of this study was to investigate whether intracellular cAMP affects LCWE-induced pathological signaling. LCWE was shown to induce phosphorylation of the nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways and cell proliferation in mice fibroblast cells. Theophylline and phosphodiesterase inhibitor increased intracellular cAMP and inhibited LCWE-induced cell proliferation as well as phosphorylation of NF-κB and MAPK. Protein kinase A inhibitor H89 prevented cAMP-induced MAPK inhibition, but not cAMP-induced NF-κB inhibition. An exchange protein activated by cAMP (Epac) agonist inhibited NF-κB activation but not MAPK activation. These results indicate that an increase in intracellular cAMP prevents LCWE induction of pathological signaling pathways dependent on PKA and Epac signaling.

  3. Frequent phosphodiesterase 11A gene (PDE11A) defects in patients with Carney complex (CNC) caused by PRKAR1A mutations: PDE11A may contribute to adrenal and testicular tumors in CNC as a modifier of the phenotype.

    Science.gov (United States)

    Libé, Rossella; Horvath, Anelia; Vezzosi, Delphine; Fratticci, Amato; Coste, Joel; Perlemoine, Karine; Ragazzon, Bruno; Guillaud-Bataille, Marine; Groussin, Lionel; Clauser, Eric; Raffin-Sanson, Marie-Laure; Siegel, Jennifer; Moran, Jason; Drori-Herishanu, Limor; Faucz, Fabio Rueda; Lodish, Maya; Nesterova, Maria; Bertagna, Xavier; Bertherat, Jerome; Stratakis, Constantine A

    2011-01-01

    Carney complex (CNC) is an autosomal dominant multiple neoplasia, caused mostly by inactivating mutations of the regulatory subunit 1A of the protein kinase A (PRKAR1A). Primary pigmented nodular adrenocortical disease (PPNAD) is the most frequent endocrine manifestation of CNC with a great inter-individual variability. Germline, protein-truncating mutations of phosphodiesterase type 11A (PDE11A) have been described to predispose to a variety of endocrine tumors, including adrenal and testicular tumors. Our objective was to investigate the role of PDE11A as a possible gene modifier of the phenotype in a series of 150 patients with CNC. A higher frequency of PDE11A variants in patients with CNC compared with healthy controls was found (25.3 vs. 6.8%, P CNC patients, those with PPNAD were significantly more frequently carriers of PDE11A variants compared with patients without PPNAD (30.8 vs. 13%, P = 0.025). Furthermore, men with PPNAD were significantly more frequently carriers of PDE11A sequence variants (40.7%) than women with PPNAD (27.3%) (P CNC patients, a high frequency of PDE11A variants, suggesting that PDE11A is a genetic modifying factor for the development of testicular and adrenal tumors in patients with germline PRKAR1A mutation.

  4. Theobromine, the primary methylxanthine found in Theobroma cacao, prevents malignant glioblastoma proliferation by negatively regulating phosphodiesterase-4, extracellular signal-regulated kinase, Akt/mammalian target of rapamycin kinase, and nuclear factor-kappa B.

    Science.gov (United States)

    Sugimoto, Naotoshi; Miwa, Shinji; Hitomi, Yoshiaki; Nakamura, Hiroyuki; Tsuchiya, Hiroyuki; Yachie, Akihiro

    2014-01-01

    Theobromine, a caffeine derivative, is the primary methylxanthine produced by Theobroma cacao. We previously showed that methylxanthines, including caffeine and theophylline, have antitumor and antiinflammatory effects, which are in part mediated by their inhibition of phosphodiesterase (PDE). A member of the PDE family, PDE4, is widely expressed in and promotes the growth of glioblastoma, the most common type of brain tumor. The purpose of this study was to determine whether theobromine could exert growth inhibitory effects on U87-MG, a cell line derived from human malignant glioma. We show that theobromine treatment elevates intracellular cAMP levels and increases the activity of p38 mitogen-activated protein kinase and c-Jun N-terminal kinase, whereas it attenuates p44/42 extracellular signal-regulated kinase activity and the Akt/mammalian target of rapamycin kinase and nuclear factor-kappa B signal pathways. It also inhibits cell proliferation. These results suggest that foods and beverages containing cocoa bean extracts, including theobromine, might be extremely effective in preventing human glioblastoma.

  5. Skin cancer associated with commonly prescribed drugs: tumor necrosis factor alpha inhibitors (TNF-αIs), angiotensin-receptor blockers (ARBs), phosphodiesterase type 5 inhibitors (PDE5Is) and statins -weighing the evidence.

    Science.gov (United States)

    Nardone, Beatrice; Orrell, Kelsey A; Vakharia, Paras P; West, Dennis P

    2018-02-01

    Skin cancers, including both malignant melanoma (MM) and nonmelanoma skin cancer (NMSC), are the most commonly diagnosed cancers in the US. The incidence of both MM and NMSC continues to rise. Areas covered: Current evidence for an association between four of the most commonly prescribed classes of drugs in the U.S. and risk for MM and NMSC is reported. Medline was searched (January 2000 to May 2017) for each drug in the classes and for 'basal cell carcinoma', 'squamous cell carcinoma', 'non-melanoma skin cancer', 'skin cancer' and 'melanoma'. Skin cancer risk information was reported for: tumor necrosis factor alpha inhibitors (TNF-αIs), angiotensin-receptor blockers (ARBs), phosphodiesterase type 5 inhibitors (PDE5Is) and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA)-reductase inhibitors (statins). Expert opinion: Since skin cancer risk is associated with all four classes of these commonly prescribed drugs that represent nearly 20% of the Top 100 drugs in the U.S., these important findings warrant enhanced education, especially for prescribers and those patients at high risk for skin cancer.

  6. The association of ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1 K121Q gene polymorphism with the risk of type 2 diabetes mellitus in European, American, and African populations: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Jonny Karunia Fajar

    2016-07-01

    Full Text Available Introduction: Several studies regarding the association of the ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1 K121Q gene polymorphism with the risk of type 2 diabetes mellitus (T2DM showed inconsistent results. This study aimed to investigate the association of ENPP1 K121Q gene polymorphism with T2DM risk using meta-analysis. The study was limited to the American, European, and African populations.Methods: PubMed and Embase databases were searched for eligible publications. The following information was extracted from each study: name of first author, publication year, country of origin, sample size of cases and controls, and size of each allele. The combined odds ratios (ORs and 95% confidence intervals (95% CIs for the association between ENPP1 K121Q gene polymorphism and T2DM risk were assessed using random or fixed effect model. A comprehensive meta-analysis (CMA 2.0 was used to analyze the data.Results: Nineteen studies (17717 cases/28022 controls on the association between ENPP1 K121Q gene polymorphism and T2DM risk were included in this meta-analysis. The results indicated that the ENPP1 K121Q gene polymorphism was associated with increased T2DM risk (Q vs. K genetic model, OR 95% CI = 1.11 [1.02–1.22], p = 0.014; QQ vs. KK + KQ, OR 95% CI = 1.14 [1.01–1.23], p = 0.039 and decreased T2DM risk (K vs. Q, OR 95% CI = 0.90 [0.82–1.00], p = 0.014; KK vs. KQ + QQ, OR 95% CI = 0.89 [0.80–0.98], p = 0.024.Conclusions: The results indicate that the ENPP1 K121Q gene polymorphism is associated with the risk of T2DM in the American, European, and African populations.

  7. Saw palmetto extract enhances erectile responses by inhibition of phosphodiesterase 5 activity and increase in inducible nitric oxide synthase messenger ribonucleic acid expression in rat and rabbit corpus cavernosum.

    Science.gov (United States)

    Yang, Surong; Chen, Changrui; Li, Yiying; Ren, Zhenghua; Zhang, Yungang; Wu, Gantong; Wang, Hao; Hu, Zhenzhen; Yao, Minghui

    2013-06-01

    To evaluate whether saw palmetto extract (SPE) relaxes corpus cavernosum and explore the underlying mechanisms. Forty Sprague-Dawley rats and 30 New Zealand rabbits were randomly allocated into 3 SPE-treated groups (low-, middle-, and high-dose) and 1 saline-treated control group. SPE was administered intragastrically for 7 consecutive days. Another 23 rats treated with sildenafil were used to appraise the erectile response to electrical stimulation of nerves in the corpus cavernosum. The erectile functions of rats and rabbits were evaluated 24 hours after the last SPE administration or 15 minutes after intragastric sildenafil. Outcome measures included corpus cavernosum electrical activity recording, phosphodiesterase 5 (PDE5) activity detected by the colorimetric quantitative method, and messenger ribonucleic acid (mRNA) expression level for PDE5 and inducible nitric oxide synthase (iNOS) determined using real-time polymerase chain reaction. In the SPE-treated animals, the relaxant response to electrical stimulation of nerves in the corpus cavernosum, reflected by the amplitude of the electrical activity within the cavernosum, was significantly and dose-dependently augmented. Similar effects were observed in the sildenafil-treated rats. PDE5 activity in rat and rabbit corpus cavernosum tissues was significantly and dose-dependently inhibited in SPE-treated animals, whereas the iNOS mRNA level increased compared with the saline group. PDE5 mRNA, however, was only significantly enhanced in the rats treated with the middle dose of SPE. The results suggest that SPE may have potential application value for the prevention or treatment of erectile dysfunction through an increase in iNOS mRNA expression and inhibition of PDE5 activity in corpus cavernosum smooth muscles. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Anti-inflammatory effects of the selective phosphodiesterase 3 inhibitor, cilostazol, and antioxidants, enzymatically-modified isoquercitrin and α-lipoic acid, reduce dextran sulphate sodium-induced colorectal mucosal injury in mice.

    Science.gov (United States)

    Kangawa, Yumi; Yoshida, Toshinori; Abe, Hajime; Seto, Yoshiki; Miyashita, Taishi; Nakamura, Michi; Kihara, Tohru; Hayashi, Shim-Mo; Shibutani, Makoto

    2017-04-04

    Developing effective treatments and preventing inflammatory bowel disease (IBD) are urgent challenges in improving patients' health. It has been suggested that platelet activation and reactive oxidative species generation are involved in the pathogenesis of IBD. We examined the inhibitory effects of a selective phosphodiesterase-3 inhibitor, cilostazol (CZ), and two antioxidants, enzymatically modified isoquercitrin (EMIQ) and α-lipoic acid (ALA), against dextran sulphate sodium (DSS)-induced colitis. BALB/c mice were treated with 0.3% CZ, 1.5% EMIQ, and 0.2% ALA in their feed. Colitis was induced by administering 5% DSS in drinking water for 8days. The inhibitory effects of these substances were evaluated by measuring relevant clinical symptoms (faecal blood, diarrhoea, and body weight loss), colon length, plasma cytokine and chemokine levels, whole genome gene expression, and histopathology. Diarrhoea was suppressed by each treatment, while CZ prevented shortening of the colon length. All treatment groups exhibited decreased plasma levels of interleukin (IL)-6 and tumour necrosis factor (TNF)-α compared with the DSS group. Microarray analysis showed that cell adhesion, cytoskeleton regulation, cell proliferation, and apoptosis, which might be related to inflammatory cell infiltration and mucosal healing, were affected in all the groups. DSS-induced mucosal injuries such as mucosal loss, submucosal oedema, and inflammatory cell infiltration in the distal colon were prevented by CZ or antioxidant treatment. These results suggest that anti-inflammatory effects of these agents reduced DSS-induced mucosal injuries in mice and, therefore, may provide therapeutic benefits in IBD. Copyright © 2016 Elsevier GmbH. All rights reserved.

  9. 3,7-Bis(2-hydroxyethyl)icaritin, a potent inhibitor of phosphodiesterase-5, prevents monocrotaline-induced pulmonary arterial hypertension via NO/cGMP activation in rats.

    Science.gov (United States)

    Lan, Tao-Hua; Chen, Xiao-Ling; Wu, Yun-Shan; Qiu, Hui-Liang; Li, Jun-Zhe; Ruan, Xin-Min; Xu, Dan-Ping; Lin, Dong-Qun

    2018-06-15

    Pulmonary arterial hypertension (PAH) is a chronic progressive disease which leads to elevated pulmonary arterial pressure and right heart failure. 3,7-Bis(2-hydroxyethyl)icaritin (ICT), an icariin derivatives, was reported to have potent inhibitory activity on phosphodiesterase type 5 (PDE5) which plays a crucial role in the pathogenesis of PAH. The present study was designed to investigate the effects of ICT on monocrotaline (MCT)-induced PAH rat model and reveal the underlying mechanism. MCT-induced PAH rat models were established with intragastric administration of ICT (10, 20, 40 mg/kg/d), Icariin (ICA) (40 mg/kg/d) and Sildenafil (25 mg/kg/d). The mean pulmonary arterial pressure (mPAP) and right ventricle hypertrophy index (RVHI) were measured. Pulmonary artery remodeling was assessed by H&E staining. Blood and lung tissue were collected to evaluate the level of endothelin 1 (ET-1), nitric oxide (NO), and cyclic guanosine monophosphate (cGMP). The expressions endothelial nitric oxide synthase (eNOS) and PDE5A in lung tissues were determined by Western blot analysis. The results showed that ICT reduced RVHI and mPAP, and reversed lung vascular remodeling in rats with MCT-induced PAH. ICT also reversed MCT-induced ET-1 elevation, NO and cGMP reduction in serum or lung tissue. Moreover, ICT administration significantly induced eNOS activation and PDE5A inhibition. ICT with lower dose had better effects than ICA. In summary, ICT is more effective in preventing MCT-induced PAH in rats via NO/cGMP activation compared with ICA. These findings demonstrate a novel mechanism of the action of ICT that may have value in prevention of PAH. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. The role of initial success rates and other factors in determining reliability of outcomes of phosphodiesterase inhibitor therapy for erectile dysfunction: a pooled analysis of 17 placebo-controlled trials of tadalafil for use as needed.

    Science.gov (United States)

    Sontag, Angelina; Rosen, Raymond C; Litman, Heather J; Ni, Xiao; Araujo, Andre B

    2013-02-01

    Reliability of successful outcomes in men with erectile dysfunction (ED) on phosphodiesterase type 5 inhibitors is an important aspect of patient management. We examined reliability of successful outcomes in a large integrated dataset of randomized tadalafil trials. Success rates, time to success, subsequent success after first success, and probability of success were analyzed based on Sexual Encounter Profile questions 2 and 3. Data from 3,254 ED patients treated with tadalafil 10 mg (N = 510), 20 mg (N = 1,772), or placebo (N = 972) were pooled from 17 placebo-controlled studies. Tadalafil patients had significantly higher first-attempt success rates vs. placebo. This effect was consistent across most subgroups; however, patients with severe ED experienced a greater response to tadalafil than patients with mild-moderate ED. Approximately 80% of patients achieved successful penile insertion within two attempts with either tadalafil dose and successful intercourse within eight attempts for tadalafil 10 mg and four attempts for tadalafil 20 mg. However, approximately 70% of tadalafil-treated patients achieved successful intercourse even by the second attempt. Subsequent success rates were higher for patients with first-attempt success (81.5% for 10 mg and 86.1% for 20 mg vs. 66.2% for placebo, P success (53.2% for 10 mg and 56.4% for 20 mg vs. 39.9% for placebo, P success rates at early attempts were similar to rates at later attempts (i.e., attempts 5 and 10 vs. 25), although insertion success rates were significantly lower earlier in treatment. The findings affirm the reliability of successful outcomes with tadalafil treatment and that first-attempt success is a critical factor affecting subsequent outcomes. The results further show that even among men who did not succeed on first attempt, a substantial proportion will have successful outcomes if treatment is maintained. © 2012 International Society for Sexual Medicine.

  11. Whole-body biodistribution and radiation dosimetry in monkeys and humans of the phosphodiesterase 4 radioligand [11C](R)-rolipram: comparison of two-dimensional planar, bisected and quadrisected image analyses

    International Nuclear Information System (INIS)

    Sprague, David R.; Fujita, Masahiro; Ryu, Yong Hoon; Liow, Jeih-San; Pike, Victor W.; Innis, Robert B.

    2008-01-01

    Introduction: [ 11 C](R)-Rolipram is a selective radioligand for positron emission tomography (PET) imaging of phosphodiesterase 4, an enzyme that metabolizes 3',5'-cyclic adenosine monophosphate. The aim of this study was to estimate the human radiation absorbed dose of the radioligand based on its biodistribution in both monkeys and humans. Methods: Whole-body PET images were acquired for 2 h after injecting [ 11 C](R)-rolipram in eight healthy humans and three monkeys. The simple method of using a single two-dimensional (2D) planar image was compared to more time-consuming methods that used two (bisected) or four (quadrisected) tomographic images in the anteroposterior direction. Results: Effective dose was 4.8 μGy/MBq based on 2D planar images. The effective dose was only slightly lower by 1% and 5% using the bisected and quadrisected images, respectively. Nevertheless, the two tomographic methods may have more accurately estimated the exposure of some organs (e.g., kidneys) that are asymmetrically located in the body or have radioactivity that appears to overlap on 2D planar images. Monkeys had a different biodistribution pattern compared to humans (e.g., greater urinary excretion) such that their data overestimated the effective dose in humans by 40%. Conclusions: The effective dose of [ 11 C](R)-rolipram was modest and comparable to that of other 11 C-labeled radioligands. The simple and far less time-consuming 2D planar method provided accurate and somewhat more conservative estimates of effective dose than the two tomographic methods. Although monkeys are commonly used to estimate human radiation exposures, their data gave a considerable overestimation for this radioligand

  12. Peripheral phosphodiesterase 4 inhibition produced by 4-[2-(3,4-Bis-difluoromethoxyphenyl)-2-[4-(1,1,1,3,3,3-hexafluoro-2-hydroxypropan-2-yl)-phenyl]-ethyl]-3-methylpyridine-1-oxide (L-826,141) prevents experimental autoimmune encephalomyelitis

    DEFF Research Database (Denmark)

    Moore, Craig S.; Earl, Nathalie; Frenette, Richard

    2006-01-01

    Administration of phosphodiesterase 4 (PDE4) inhibitors suppresses the pathogenesis associated with experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). In the present study, we compared the effects of rolipram and 4-[2-(3,4-bis-difluoromethoxyphenyl)-2...... observed. Only L-826,141 at a dose of 30 mg/kg p.o. significantly decreased the clinical severity of EAE compared with vehicle controls. Immunohistochemical detection of the neuronal activity marker Fos confirmed that L-826,141 did not reach concentrations in the central nervous system sufficient...

  13. Ultrastructural and Molecular Analyses Reveal Enhanced Nucleolar Activity in Medicago truncatula Cells Overexpressing the MtTdp2α Gene

    Science.gov (United States)

    Macovei, Anca; Faè, Matteo; Biggiogera, Marco; de Sousa Araújo, Susana; Carbonera, Daniela; Balestrazzi, Alma

    2018-01-01

    The role of tyrosyl-DNA phosphodiesterase 2 (Tdp2) involved in the repair of 5′-end-blocking DNA lesions is still poorly explored in plants. To gain novel insights, Medicago truncatula suspension cultures overexpressing the MtTdp2α gene (Tdp2α-13C and Tdp2α-28 lines, respectively) and a control (CTRL) line carrying the empty vector were investigated. Transmission electron microscopy (TEM) revealed enlarged nucleoli (up to 44% expansion of the area, compared to CTRL), the presence of nucleolar vacuoles, increased frequency of multinucleolate cells (up to 4.3-fold compared to CTRL) and reduced number of ring-shaped nucleoli in Tdp2α-13C and Tdp2α-28 lines. Ultrastructural data suggesting for enhanced nucleolar activity in MtTdp2α-overexpressing lines were integrated with results from bromouridine incorporation. The latter revealed an increase of labeled transcripts in both Tdp2α-13C and Tdp2α-28 cells, within the nucleolus and in the extra-nucleolar region. MtTdp2α-overexpressing cells showed tolerance to etoposide, a selective inhibitor of DNA topoisomerase II, as evidenced by DNA diffusion assay. TEM analysis revealed etoposide-induced rearrangements within the nucleolus, resembling the nucleolar caps observed in animal cells under transcription impairment. Based on these findings it is evident that MtTdp2α-overexpression enhances nucleolar activity in plant cells. PMID:29868059

  14. Ultrastructural and Molecular Analyses Reveal Enhanced Nucleolar Activity in Medicago truncatula Cells Overexpressing the MtTdp2α Gene

    Directory of Open Access Journals (Sweden)

    Anca Macovei

    2018-05-01

    Full Text Available The role of tyrosyl-DNA phosphodiesterase 2 (Tdp2 involved in the repair of 5′-end-blocking DNA lesions is still poorly explored in plants. To gain novel insights, Medicago truncatula suspension cultures overexpressing the MtTdp2α gene (Tdp2α-13C and Tdp2α-28 lines, respectively and a control (CTRL line carrying the empty vector were investigated. Transmission electron microscopy (TEM revealed enlarged nucleoli (up to 44% expansion of the area, compared to CTRL, the presence of nucleolar vacuoles, increased frequency of multinucleolate cells (up to 4.3-fold compared to CTRL and reduced number of ring-shaped nucleoli in Tdp2α-13C and Tdp2α-28 lines. Ultrastructural data suggesting for enhanced nucleolar activity in MtTdp2α-overexpressing lines were integrated with results from bromouridine incorporation. The latter revealed an increase of labeled transcripts in both Tdp2α-13C and Tdp2α-28 cells, within the nucleolus and in the extra-nucleolar region. MtTdp2α-overexpressing cells showed tolerance to etoposide, a selective inhibitor of DNA topoisomerase II, as evidenced by DNA diffusion assay. TEM analysis revealed etoposide-induced rearrangements within the nucleolus, resembling the nucleolar caps observed in animal cells under transcription impairment. Based on these findings it is evident that MtTdp2α-overexpression enhances nucleolar activity in plant cells.

  15. TDP2 suppresses chromosomal translocations induced by DNA topoisomerase II during gene transcription.

    Science.gov (United States)

    Gómez-Herreros, Fernando; Zagnoli-Vieira, Guido; Ntai, Ioanna; Martínez-Macías, María Isabel; Anderson, Rhona M; Herrero-Ruíz, Andrés; Caldecott, Keith W

    2017-08-10

    DNA double-strand breaks (DSBs) induced by abortive topoisomerase II (TOP2) activity are a potential source of genome instability and chromosome translocation. TOP2-induced DNA double-strand breaks are rejoined in part by tyrosyl-DNA phosphodiesterase 2 (TDP2)-dependent non-homologous end-joining (NHEJ), but whether this process suppresses or promotes TOP2-induced translocations is unclear. Here, we show that TDP2 rejoins DSBs induced during transcription-dependent TOP2 activity in breast cancer cells and at the translocation 'hotspot', MLL. Moreover, we find that TDP2 suppresses chromosome rearrangements induced by TOP2 and reduces TOP2-induced chromosome translocations that arise during gene transcription. Interestingly, however, we implicate TDP2-dependent NHEJ in the formation of a rare subclass of translocations associated previously with therapy-related leukemia and characterized by junction sequences with 4-bp of perfect homology. Collectively, these data highlight the threat posed by TOP2-induced DSBs during transcription and demonstrate the importance of TDP2-dependent non-homologous end-joining in protecting both gene transcription and genome stability.DNA double-strand breaks (DSBs) induced by topoisomerase II (TOP2) are rejoined by TDP2-dependent non-homologous end-joining (NHEJ) but whether this promotes or suppresses translocations is not clear. Here the authors show that TDP2 suppresses chromosome translocations from DSBs introduced during gene transcription.

  16. Divergent Requirement for a DNA Repair Enzyme during Enterovirus Infections

    Directory of Open Access Journals (Sweden)

    Sonia Maciejewski

    2015-12-01

    Full Text Available Viruses of the Enterovirus genus of picornaviruses, including poliovirus, coxsackievirus B3 (CVB3, and human rhinovirus, commandeer the functions of host cell proteins to aid in the replication of their small viral genomic RNAs during infection. One of these host proteins is a cellular DNA repair enzyme known as 5′ tyrosyl-DNA phosphodiesterase 2 (TDP2. TDP2 was previously demonstrated to mediate the cleavage of a unique covalent linkage between a viral protein (VPg and the 5′ end of picornavirus RNAs. Although VPg is absent from actively translating poliovirus mRNAs, the removal of VPg is not required for the in vitro translation and replication of the RNA. However, TDP2 appears to be excluded from replication and encapsidation sites during peak times of poliovirus infection of HeLa cells, suggesting a role for TDP2 during the viral replication cycle. Using a mouse embryonic fibroblast cell line lacking TDP2, we found that TDP2 is differentially required among enteroviruses. Our single-cycle viral growth analysis shows that CVB3 replication has a greater dependency on TDP2 than does poliovirus or human rhinovirus replication. During infection, CVB3 protein accumulation is undetectable (by Western blot analysis in the absence of TDP2, whereas poliovirus protein accumulation is reduced but still detectable. Using an infectious CVB3 RNA with a reporter, CVB3 RNA could still be replicated in the absence of TDP2 following transfection, albeit at reduced levels. Overall, these results indicate that TDP2 potentiates viral replication during enterovirus infections of cultured cells, making TDP2 a potential target for antiviral development for picornavirus infections.

  17. The cutting edges in DNA repair, licensing, and fidelity: DNA and RNA repair nucleases sculpt DNA to measure twice, cut once.

    Science.gov (United States)

    Tsutakawa, Susan E; Lafrance-Vanasse, Julien; Tainer, John A

    2014-07-01

    To avoid genome instability, DNA repair nucleases must precisely target the correct damaged substrate before they are licensed to incise. Damage identification is a challenge for all DNA damage response proteins, but especially for nucleases that cut the DNA and necessarily create a cleaved DNA repair intermediate, likely more toxic than the initial damage. How do these enzymes achieve exquisite specificity without specific sequence recognition or, in some cases, without a non-canonical DNA nucleotide? Combined structural, biochemical, and biological analyses of repair nucleases are revealing their molecular tools for damage verification and safeguarding against inadvertent incision. Surprisingly, these enzymes also often act on RNA, which deserves more attention. Here, we review protein-DNA structures for nucleases involved in replication, base excision repair, mismatch repair, double strand break repair (DSBR), and telomere maintenance: apurinic/apyrimidinic endonuclease 1 (APE1), Endonuclease IV (Nfo), tyrosyl DNA phosphodiesterase (TDP2), UV Damage endonuclease (UVDE), very short patch repair endonuclease (Vsr), Endonuclease V (Nfi), Flap endonuclease 1 (FEN1), exonuclease 1 (Exo1), RNase T and Meiotic recombination 11 (Mre11). DNA and RNA structure-sensing nucleases are essential to life with roles in DNA replication, repair, and transcription. Increasingly these enzymes are employed as advanced tools for synthetic biology and as targets for cancer prognosis and interventions. Currently their structural biology is most fully illuminated for DNA repair, which is also essential to life. How DNA repair enzymes maintain genome fidelity is one of the DNA double helix secrets missed by James Watson and Francis Crick, that is only now being illuminated though structural biology and mutational analyses. Structures reveal motifs for repair nucleases and mechanisms whereby these enzymes follow the old carpenter adage: measure twice, cut once. Furthermore, to measure

  18. Structural and functional characterization of a novel molluskan ortholog of TRAF and TNF receptor-associated protein from disk abalone (Haliotis discus discus).

    Science.gov (United States)

    Lee, Youngdeuk; Elvitigala, Don Anushka Sandaruwan; Whang, Ilson; Lee, Sukkyoung; Kim, Hyowon; Zoysa, Mahanama De; Oh, Chulhong; Kang, Do-Hyung; Lee, Jehee

    2014-09-01

    Immune signaling cascades have an indispensable role in the host defense of almost all the organisms. Tumor necrosis factor (TNF) signaling is considered as a prominent signaling pathway in vertebrate as well as invertebrate species. Within the signaling cascade, TNF receptor-associated factor (TRAF) and TNF receptor-associated protein (TTRAP) has been shown to have a crucial role in the modulation of immune signaling in animals. Here, we attempted to characterize a novel molluskan ortholog of TTRAP (AbTTRAP) from disk abalone (Haliotis discus discus) and analyzed its expression levels under pathogenic stress. The complete coding sequence of AbTTRAP consisted of 1071 nucleotides, coding for a 357 amino acid peptide, with a predicted molecular mass of 40 kDa. According to our in-silico analysis, AbTTRAP resembled the typical TTRAP domain architecture, including a 5'-tyrosyl DNA phosphodiesterase domain. Moreover, phylogenetic analysis revealed its common ancestral invertebrate origin, where AbTTRAP was clustered with molluskan counterparts. Quantitative real time PCR showed universally distributed expression of AbTTRAP in selected tissues of abalone, from which more prominent expression was detected in hemocytes. Upon stimulation with two pathogen-derived mitogens, lipopolysaccharide (LPS) and polyinosinic:polycytidylic acid (poly I:C), transcript levels of AbTTRAP in hemocytes and gill tissues were differentially modulated with time. In addition, the recombinant protein of AbTTRAP exhibited prominent endonuclease activity against abalone genomic DNA, which was enhanced by the presence of Mg(2+) in the medium. Collectively, these results reinforce the existence of the TNF signaling cascade in mollusks like disk abalone, further implicating the putative regulatory behavior of TTRAP in invertebrate host pathology. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Four Novel p.N385K, p.V36A, c.1033–1034insT and c.1417–1418delCT Mutations in the Sphingomyelin Phosphodiesterase 1 (SMPD1 Gene in Patients with Types A and B Niemann-Pick Disease (NPD

    Directory of Open Access Journals (Sweden)

    Masoumeh Dehghan Manshadi

    2015-03-01

    Full Text Available Background: Types A and B Niemann-Pick disease (NPD are autosomal-recessive lysosomal storage disorders caused by the deficient activity of acid sphingomyelinase due to mutations in the sphingomyelin phosphodiesterase 1 (SMPD1 gene. Methods: In order to determine the prevalence and distribution of SMPD1 gene mutations, the genomic DNA of 15 unrelated Iranian patients with types A and B NPD was examined using PCR, DNA sequencing and bioinformatics analysis. Results: Of 8 patients with the p.G508R mutation, 5 patients were homozygous, while the other 3 were heterozygous. One patient was heterozygous for both the p.N385K and p.G508R mutations. Another patient was heterozygous for both the p.A487V and p.G508R mutations. Two patients (one homozygous and one heterozygous showed the p.V36A mutation. One patient was homozygous for the c.1033–1034insT mutation. One patient was homozygous for the c.573delT mutation, and 1 patient was homozygous for the c.1417–1418delCT mutation. Additionally, bioinformatics analysis indicated that two new p.V36A and p.N385K mutations decreased the acid sphingomyelinase (ASM protein stability, which might be evidence to suggest the pathogenicity of these mutations. Conclusion: with detection of these new mutations, the genotypic spectrum of types A and B NPD is extended, facilitating the definition of disease-related mutations. However, more research is essential to confirm the pathogenic effect of these mutations.

  20. Phosphodiesterase 1 regulation is a key mechanism in vascular aging

    DEFF Research Database (Denmark)

    Niño, Paula K Bautista; Durik, Matej; Danser, A H Jan

    2015-01-01

    Reduced nitric oxide (NO)/cGMP signalling is observed in age-related vascular disease. We hypothesize that this disturbed signalling involves effects of genomic instability, a primary causal factor in aging, on vascular smooth muscle cells (VSMCs) and that the underlying mechanism plays a role...... in human age-related vascular disease. To test our hypothesis, we combined experiments in mice with genomic instability resulting from the defective nucleotide excision repair gene ERCC1 (Ercc1(d/-) mice), human VSMC cultures and population genome-wide association studies (GWAS). Aortic rings of Ercc1(d...... in lungs was higher in Ercc1(d/-) mice. No differences in activity or levels of cGMP-dependent protein kinase 1 or sGC were observed in Ercc1(d/-) mice compared with WT. Senescent human VSMC showed elevated PDE1A and PDE1C and PDE5 mRNA levels (11.6-, 9- and 2.3-fold respectively), which associated...

  1. Discovery of Selective Phosphodiesterase 1 Inhibitors with Memory Enhancing Properties.

    Science.gov (United States)

    Dyck, Brian; Branstetter, Bryan; Gharbaoui, Tawfik; Hudson, Andrew R; Breitenbucher, J Guy; Gomez, Laurent; Botrous, Iriny; Marrone, Tami; Barido, Richard; Allerston, Charles K; Cedervall, E Peder; Xu, Rui; Sridhar, Vandana; Barker, Ryan; Aertgeerts, Kathleen; Schmelzer, Kara; Neul, David; Lee, Dong; Massari, Mark Eben; Andersen, Carsten B; Sebring, Kristen; Zhou, Xianbo; Petroski, Robert; Limberis, James; Augustin, Martin; Chun, Lawrence E; Edwards, Thomas E; Peters, Marco; Tabatabaei, Ali

    2017-04-27

    A series of potent thienotriazolopyrimidinone-based PDE1 inhibitors was discovered. X-ray crystal structures of example compounds from this series in complex with the catalytic domain of PDE1B and PDE10A were determined, allowing optimization of PDE1B potency and PDE selectivity. Reduction of hERG affinity led to greater than a 3000-fold selectivity for PDE1B over hERG. 6-(4-Methoxybenzyl)-9-((tetrahydro-2H-pyran-4-yl)methyl)-8,9,10,11-tetrahydropyrido[4',3':4,5]thieno[3,2-e][1,2,4]triazolo[1,5-c]pyrimidin-5(6H)-one was identified as an orally bioavailable and brain penetrating PDE1B enzyme inhibitor with potent memory-enhancing effects in a rat model of object recognition memory.

  2. Characterization of the "Escherichia Coli" Acyl Carrier Protein Phosphodiesterase

    Science.gov (United States)

    Thomas, Jacob

    2009-01-01

    Acyl carrier protein (ACP) is a small essential protein that functions as a carrier of the acyl intermediates of fatty acid synthesis. ACP requires the posttranslational attachment of a 4'phosphopantetheine functional group, derived from CoA, in order to perform its metabolic function. A Mn[superscript 2+] dependent enzymatic activity that removes…

  3. Atividade das fosfodiesterases em tecido de granulação submetido a irradiação de elétrons - estudo experimental em ratos Activity of phosphodiesterases in granulation tissue submitted to electron irradiation - experimental study in rats

    Directory of Open Access Journals (Sweden)

    Frab Norberto BÓSCOLO

    2001-09-01

    Full Text Available Os autores estudaram o efeito de baixas doses de radiação de elétrons na atividade de fosfodiesterases presentes no tecido de granulação, induzido por esponja de PVC, subcutaneamente, na região dorsal de 84 ratos Wistar, divididos em dois grupos, controle e irradiado. A atividade enzimática foi avaliada segundo a evolução do tecido de granulação aos 5, 7, 10, 14, 17, 20 e 24 dias. Os animais foram irradiados com um feixe de elétrons de 6 MeV, dose de 1 Gy, 3 dias após a implantação da esponja, sendo que no momento da irradiação, foram protegidos por uma lâmina de 4 mm de chumbo, tendo sido irradiada somente a área correspondente ao local onde encontrava-se a esponja. Considerando-se a dose e o tipo de radiação empregada, pode-se concluir que houve influência direta da radiação na atividade da enzima 5’-nucleotidase e da ATPase no início do processo de reparação tecidual, aos 5 e 7 dias. Já a enzima fosfatase alcalina não sofreu a ação direta da radiação. É possível que o principal fator tenha sido danos nos constituintes celulares que são responsáveis pela formação do tecido de granulação, determinando a produção enzimática conforme a necessidade.The present study evaluated the effect of low doses of electron radiation on the activity of phosphodiesterases in granulation tissue. In order to induce growth of granulation tissue, a PVC sponge disk was introduced under the dorsal skin of 84 Wistar rats. The rats were divided in two groups, control and irradiated. The enzymatic activity was evaluated according to the evolution of the granulation tissue after 5, 7, 10, 14, 17, 20 and 24 days. Irradiation was carried out 3 days after the implantation of the sponge, by means of a linear accelerator, with energy of 6 MeV, and dose of 1.0 Gy. The results of this study showed that 5’-nucleotidase and ATPase had their activity directly affected by irradiation only in the beginning of the tissue repairing

  4. Divergent Requirement for a DNA Repair Enzyme during Enterovirus Infections.

    Science.gov (United States)

    Maciejewski, Sonia; Nguyen, Joseph H C; Gómez-Herreros, Fernando; Cortés-Ledesma, Felipe; Caldecott, Keith W; Semler, Bert L

    2015-12-29

    Viruses of the Enterovirus genus of picornaviruses, including poliovirus, coxsackievirus B3 (CVB3), and human rhinovirus, commandeer the functions of host cell proteins to aid in the replication of their small viral genomic RNAs during infection. One of these host proteins is a cellular DNA repair enzyme known as 5' tyrosyl-DNA phosphodiesterase 2 (TDP2). TDP2 was previously demonstrated to mediate the cleavage of a unique covalent linkage between a viral protein (VPg) and the 5' end of picornavirus RNAs. Although VPg is absent from actively translating poliovirus mRNAs, the removal of VPg is not required for the in vitro translation and replication of the RNA. However, TDP2 appears to be excluded from replication and encapsidation sites during peak times of poliovirus infection of HeLa cells, suggesting a role for TDP2 during the viral replication cycle. Using a mouse embryonic fibroblast cell line lacking TDP2, we found that TDP2 is differentially required among enteroviruses. Our single-cycle viral growth analysis shows that CVB3 replication has a greater dependency on TDP2 than does poliovirus or human rhinovirus replication. During infection, CVB3 protein accumulation is undetectable (by Western blot analysis) in the absence of TDP2, whereas poliovirus protein accumulation is reduced but still detectable. Using an infectious CVB3 RNA with a reporter, CVB3 RNA could still be replicated in the absence of TDP2 following transfection, albeit at reduced levels. Overall, these results indicate that TDP2 potentiates viral replication during enterovirus infections of cultured cells, making TDP2 a potential target for antiviral development for picornavirus infections. Picornaviruses are one of the most prevalent groups of viruses that infect humans and livestock worldwide. These viruses include the human pathogens belonging to the Enterovirus genus, such as poliovirus, coxsackievirus B3 (CVB3), and human rhinovirus. Diseases caused by enteroviruses pose a major problem

  5. Guanidine-based polymer brushes grafted onto silica nanoparticles as efficient artificial phosphodiesterases.

    Science.gov (United States)

    Savelli, Claudia; Salvio, Riccardo

    2015-04-07

    Polymer brushes grafted to the surface of silica nanoparticles were fabricated by atom-transfer radical polymerization (ATRP) and investigated as catalysts in the cleavage of phosphodiesters. The surfaces of silica nanoparticles were functionalized with an ATRP initiator. Surface-initiated ATRP reactions, in varying proportions, of a methacrylate moiety functionalized with a phenylguanidine moiety and an inert hydrophilic methacrylate species afforded hybrid nanoparticles that were characterized with potentiometric titrations, thermogravimetric analysis, and SEM. The activity of the hybrid nanoparticles was tested in the transesterification of the RNA model compound 2-hydroxypropyl para-nitrophenylphosphate (HPNP) and diribonucleoside monophosphates. A high catalytic efficiency and a remarkable effective molarity, thus overcoming the effective molarities previously observed for comparable systems, indicate the existence of an effective cooperation of the guanidine/guanidinium units and a high level of preorganization in the nanostructure. The investigated system also exhibits a marked and unprecedented selectivity for the diribonucleoside sequence CpA. The results presented open up the way for a novel and straightforward strategy for the preparation of supramolecular catalysts. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. The Phosphodiesterase 4 Inhibitor Prevents Antigen-induced Biphasic Nasal Obstruction in Brown Norway Rats

    Directory of Open Access Journals (Sweden)

    Hirokazu Kawasaki

    2005-01-01

    Conclusions: The present study provides a simple model of allergic biphasic nasal obstruction in BN rats, and also suggests that the PDE4 inhibitor may alleviate nasal obstruction in patients with allergic rhinitis.

  7. Control of renin secretion from rat juxtaglomerular cells by cAMP-specific phosphodiesterases

    DEFF Research Database (Denmark)

    Friis, Ulla G; Jensen, Boye L; Sethi, Shala

    2002-01-01

    , and the PDE4 inhibitor rolipram enhanced cellular cAMP content. Dialysis of single JG cells with cAMP in whole-cell patch-clamp experiments led to concentration-dependent, biphasic changes in cell membrane capacitance (C(m)) with a marked increase in C(m) at 1 micromol/L, no net change at 10 micromol....../L, and a decrease at 100 micromol/L cAMP. cGMP also had a dual effect on C(m) at 10-fold higher concentration compared with cAMP. Trequinsin, milrinone, and rolipram mimicked the effect of cAMP on C(m). Trequinsin, cAMP, and cGMP enhanced outward current 2- to 3-fold at positive membrane potentials. The effects...... of cAMP, cGMP, and trequinsin on C(m) and cell currents were abolished by inhibition of protein kinase A with Rp-cAMPs. We conclude that degradation of cAMP by PDE3 and PDE4 contributes to regulation of renin release from JG cells. Our data provide evidence at the cellular level that stimulation...

  8. Role of phosphodiesterase inhibitor Ibudilast in morphine-induced hippocampal injury

    Directory of Open Access Journals (Sweden)

    Mohsen Zhaleh

    2014-07-01

    Full Text Available Abstract: Background: Opioid drugs are used in the treatment of acute post-surgical pain and chronic pain, such as those associated with cancer. Opioid used is associated with complications such as analgesic tolerance, dependence and opioid abuse. The molecular mechanisms of unwanted opioid responses are varied but recent advances have highlighted elevations in pro-inflammatory cytokines and pro-inflammatory glial following chronic administration of morphine. In this study we investigated the neurodegenerative effects of morphine through its effects on Toll-Like Receptor 4 (TLR4 in the male rat hippocampus and evaluated the level of Interleukin-1 beta (IL-1β. Then we compared the difference between inhibitory effects on mu opioid receptors (by β-Funaltrexamine, β-FNA and TLR4 (by Ibudilast. Subsequently, we assessed the amount of IL-1β and the number of granular cells in male rat hippocampus. Methods: Adult male rats (n=24 were treated with sucrose, morphine, Ibudilast (7.5 mg/kg and β-FNA (20 mg/kg for 30 days. Their brains were isolated and hemisected with one hippocampus for granular cell and the other used for IL-1 β immunoblotting. Results: Data showed that Ibudilast suppresses IL-1 β expression significantly more than β-FNA. The granular cell count displayed significant differences. Conclusions: Our results suggested that Ibudilast can be used for controlling and treatment of morphine-induced CNS inflammations or traumatic conditions.

  9. Comparison of phosphodiesterase type V inhibitors use in eight European cities through analysis of urban wastewater

    DEFF Research Database (Denmark)

    Causanilles, Ana; Rojas Cantillano, Daniela; Emke, Erik

    2018-01-01

    active pharmaceutical ingredients (sildenafil, tadalafil and vardenafil) together with (bio)transformation products and other analogues. Only sildenafil and its two human urinary metabolites desmethyl- and desethylsildenafil were detected in the samples with concentrations reaching 60 ng L−1....... The concentrations were transformed into normalized measured loads and the estimated actual consumption of sildenafil was back-calculated from these loads. In addition, national prescription data from five countries was gathered in the form of the number of prescribed daily doses and transformed into predicted loads...

  10. Novel benzimidazole derivatives as phosphodiesterase 10A (PDE10A) inhibitors with improved metabolic stability.

    Science.gov (United States)

    Chino, Ayaka; Masuda, Naoyuki; Amano, Yasushi; Honbou, Kazuya; Mihara, Takuma; Yamazaki, Mayako; Tomishima, Masaki

    2014-07-01

    In this study, we report the identification of potent benzimidazoles as PDE10A inhibitors. We first identified imidazopyridine 1 as a high-throughput screening hit compound from an in-house library. Next, optimization of the imidazopyridine moiety to improve inhibitory activity gave imidazopyridinone 10b. Following further structure-activity relationship development by reducing lipophilicity and introducing substituents, we acquired 35, which exhibited both improved metabolic stability and reduced CYP3A4 time-dependent inhibition. Copyright © 2014. Published by Elsevier Ltd.

  11. Erectile dysfunction in patients taking psychotropic drugs and treated with phosphodiesterase-5 inhibitors

    Directory of Open Access Journals (Sweden)

    Rossella Mazzilli

    2018-03-01

    Full Text Available Objectives: The aim of this study was to assess the prevalence of patients with Erectile Dysfunction (ED receiving psychotropic drugs, the impact of these drugs on hormonal profile, and the efficacy of PDE5-i in these patients. Materials and methods: We recruited 1872 patients referring for ED to our Andrology Unit. Assessment included serum testosterone, gonadotropins, TSH, prolactin, and PSA, and the IIEF-5 questionnaire for ED diagnosis. Inclusion criteria were age 21-75 years and IIEF-5 total score ≤ 21; exclusion criteria included hypogonadism, diabetes mellitus, previous prostatectomy, other medication intake, and ED diagnosis prior to psychotropic drug treatment. Efficacy was rated with the IIEF-5 (remission: total score ≥ 22. Results: The prevalence of ED patients treated with psychotropic drugs since ≥ 3 months was 9.5% (178/1872, subdivided according to the drugs used into: Group A, 16 patients treated with atypical antipsychotics (9.0%; Group B, 55 patients with benzodiazepines (30.9%; Group C, 33 patients with antidepressant drugs (18.5%; and Group D, 74 patients with multiple psychotropic drugs (41.6%. Patients in Group A were significantly younger than other groups (p < 0.05. The hormonal profile presented only higher prolactin level in patients treated with antipsychotics, alone or in combination (p < 0.05. Overall, 146 patients received PDE5-i. Remission rate, after three months of treatment, was significantly higher in Group B compared to C and D groups (p < 0.05. Conclusions: A substantial portion of patients receiving psychotropic drugs show ED. Sexual performance in these patients benefits from PDE5-i. Age, effects of psychiatric disorders, psychotropic drugs, and PDE5-i treatment modality accounted for variability of response in this sample.

  12. Human 2'-phosphodiesterase localizes to the mitochondrial matrix with a putative function in mitochondrial RNA turnover

    DEFF Research Database (Denmark)

    Poulsen, Jesper Buchhave; Andersen, Kasper Røjkjær; Kjær, Karina Hansen

    2011-01-01

    . Interestingly, 2′-PDE shares both functionally and structurally characteristics with the CCR4-type exonuclease–endonuclease–phosphatase family of deadenylases. Here we show that 2′-PDE locates to the mitochondrial matrix of human cells, and comprise an active 3′–5′ exoribonuclease exhibiting a preference...

  13. Subcellular localization and regulation of type-1C and type-5 phosphodiesterases

    International Nuclear Information System (INIS)

    Dolci, Susanna; Belmonte, Alessia; Santone, Rocco; Giorgi, Mauro; Pellegrini, Manuela; Carosa, Eleonora; Piccione, Emilio; Lenzi, Andrea; Jannini, Emmanuele A.

    2006-01-01

    We investigated the subcellular localization of PDE5 in in vitro human myometrial cells. We demonstrated for First time that PDE5 is localized in discrete cytoplasmic foci and vesicular compartments corresponding to centrosomes. We also found that PDE5 intracellular localization is not cell- or species-specific, as it is conserved in different animal and human cells. PDE5 protein levels are strongly regulated by the mitotic activity of the smooth muscle cells (SMCs), as they were increased in quiescent, contractile myometrial cultures, and conditions in which proliferation was inhibited. In contrast, PDE1C levels decreased in all conditions that inhibited proliferation. This mirrored the enzymatic activity of both PDE5 and PDE1C. Increasing cGMP intracellular levels by dbcGMP or sildenafil treatments did not block proliferation, while dbcAMP inhibited myometrial cell proliferation. Together, these results suggest that PDE5 regulation of cGMP intracellular levels is not involved in the control of SMC cycle progression, but may represent one of the markers of the contractile phenotype

  14. Phosphodiesterase 5 and effects of sildenafil on cerebral arteries of man and guinea pig

    DEFF Research Database (Denmark)

    Kruuse, Christina; Khurana, Tejvir S; Rybalkin, Sergei D

    2005-01-01

    and UK-114,542, and a PDE1 inhibitor UK-90,234 on cGMP hydrolysis were investigated in human and guinea pig cerebral arteries. The vasoactive responses of the compounds were evaluated in guinea pig basilar arteries in vitro, with concomitant measurements of cAMP and cGMP. PDE5 was found in human middle...... cerebral arteries. Sildenafil and UK-114,542 inhibited cGMP hydrolysis concentration-dependently in both species. In guinea pig arteries, sildenafil induced an endothelium-dependent vasodilatation only at concentrations above 10 nM, which was augmented by sodium nitroprusside and attenuated by reduction...... of cGMP, but was cGMP independent at high concentrations. UK-114,542 was more and UK-90,234 was less potent than sildenafil. In conclusion, PDE5 is present in human and guinea pig cerebral arteries, and is inhibited by sildenafil at micromolar levels. Sildenafil in vitro is a poor dilator of guinea pig...

  15. Comparative analysis of diguanylate cyclase and phosphodiesterase genes in Klebsiella pneumoniae.

    Science.gov (United States)

    Cruz, Diana P; Huertas, Mónica G; Lozano, Marcela; Zárate, Lina; Zambrano, María Mercedes

    2012-07-09

    Klebsiella pneumoniae can be found in environmental habitats as well as in hospital settings where it is commonly associated with nosocomial infections. One of the factors that contribute to virulence is its capacity to form biofilms on diverse biotic and abiotic surfaces. The second messenger Bis-(3'-5')-cyclic dimeric GMP (c-di-GMP) is a ubiquitous signal in bacteria that controls biofilm formation as well as several other cellular processes. The cellular levels of this messenger are controlled by c-di-GMP synthesis and degradation catalyzed by diguanylate cyclase (DGC) and phophodiesterase (PDE) enzymes, respectively. Many bacteria contain multiple copies of these proteins with diverse organizational structure that highlight the complex regulatory mechanisms of this signaling network. This work was undertaken to identify DGCs and PDEs and analyze the domain structure of these proteins in K. pneumoniae. A search for conserved GGDEF and EAL domains in three sequenced K. pneumoniae genomes showed that there were multiple copies of GGDEF and EAL containing proteins. Both single domain and hybrid GGDEF proteins were identified: 21 in K. pneumoniae Kp342, 18 in K. pneumoniae MGH 78578 and 17 in K. pneumoniae NTUH-K2044. The majority had only the GGDEF domain, most with the GGEEF motif, and hybrid proteins containing both GGDEF and EAL domains were also found. The I site for allosteric control was identified only in single GGDEF domain proteins and not in hybrid proteins. EAL-only proteins, containing either intact or degenerate domains, were also identified: 15 in Kp342, 15 in MGH 78578 and 10 in NTUH-K2044. Several input sensory domains and transmembrane segments were identified, which together indicate complex regulatory circuits that in many cases can be membrane associated. The comparative analysis of proteins containing GGDEF/EAL domains in K. pneumoniae showed that most copies were shared among the three strains and that some were unique to a particular strain. The multiplicity of these proteins and the diversity of structural characteristics suggest that the c-di-GMP network in this enteric bacterium is highly complex and reflects the importance of having diverse mechanisms to control cellular processes in environments as diverse as soils or plants and clinical settings.

  16. Comparative analysis of diguanylate cyclase and phosphodiesterase genes in Klebsiella pneumoniae

    Directory of Open Access Journals (Sweden)

    Cruz Diana P

    2012-07-01

    Full Text Available Abstract Background Klebsiella pneumoniae can be found in environmental habitats as well as in hospital settings where it is commonly associated with nosocomial infections. One of the factors that contribute to virulence is its capacity to form biofilms on diverse biotic and abiotic surfaces. The second messenger Bis-(3’-5’-cyclic dimeric GMP (c-di-GMP is a ubiquitous signal in bacteria that controls biofilm formation as well as several other cellular processes. The cellular levels of this messenger are controlled by c-di-GMP synthesis and degradation catalyzed by diguanylate cyclase (DGC and phophodiesterase (PDE enzymes, respectively. Many bacteria contain multiple copies of these proteins with diverse organizational structure that highlight the complex regulatory mechanisms of this signaling network. This work was undertaken to identify DGCs and PDEs and analyze the domain structure of these proteins in K. pneumoniae. Results A search for conserved GGDEF and EAL domains in three sequenced K. pneumoniae genomes showed that there were multiple copies of GGDEF and EAL containing proteins. Both single domain and hybrid GGDEF proteins were identified: 21 in K. pneumoniae Kp342, 18 in K. pneumoniae MGH 78578 and 17 in K. pneumoniae NTUH-K2044. The majority had only the GGDEF domain, most with the GGEEF motif, and hybrid proteins containing both GGDEF and EAL domains were also found. The I site for allosteric control was identified only in single GGDEF domain proteins and not in hybrid proteins. EAL-only proteins, containing either intact or degenerate domains, were also identified: 15 in Kp342, 15 in MGH 78578 and 10 in NTUH-K2044. Several input sensory domains and transmembrane segments were identified, which together indicate complex regulatory circuits that in many cases can be membrane associated. Conclusions The comparative analysis of proteins containing GGDEF/EAL domains in K. pneumoniae showed that most copies were shared among the three strains and that some were unique to a particular strain. The multiplicity of these proteins and the diversity of structural characteristics suggest that the c-di-GMP network in this enteric bacterium is highly complex and reflects the importance of having diverse mechanisms to control cellular processes in environments as diverse as soils or plants and clinical settings.

  17. Physiological studies on the effect of a phosphodiesterase inhibitor on the blood obtained from hypothyroid rats

    International Nuclear Information System (INIS)

    Abdel-Ghany, I.Y.

    1997-01-01

    In the present study 300 male albino rats (100-120 g) were used. The search was planned to evaluate the biochemical effects of the therapeutic drug (pentoxifylline) in combination with thyroxine on the hypothyroid mammals. The biochemical determinations were serum: Tri-iodothyronine (T-3), thyroxine (T-4), Glucose, total protein, urea, creatinine, along with the enzymatic activities of : alkaline phosphatase (ALP), lactate dehydrogenase (LDH), glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT). The study included also glycogen, lactic acid, pyruvic acid, along with the enzymatic activities of : LDH, GOT and GPT in liver tissue homogenate. The data obtained, revealed significant alterations in assayed parameters reflecting disturbance in the metabolism due to hypothyroid state. Treatment of rats with thyroxine and / or pentoxifylline revealed significant amelioration in most of the tested parameters indicating the beneficial effect of these drugs. 17 tabs.,17 figs.,123 refs

  18. Phosphodiesterase activity is regulated by CC2D1A that is implicated in non-syndromic intellectual disability

    KAUST Repository

    Altawashi, Azza; Gehring, Christoph A

    2013-01-01

    to as Non Syndromic Mental Retardation (NSMR). Findings. Here we demonstrate that in Mouse Embryonic Fibroblasts (MEF) CC2D1A co-localizes with PDE4D in the cytosol before cAMP stimulation and on the periphery after stimulation, and that the movement

  19. Differential regulation of TNF-α and IL-1β production from endotoxin stimulated human monocytes by phosphodiesterase inhibitors

    Directory of Open Access Journals (Sweden)

    K. L. Molnar-Kimber

    1992-01-01

    Full Text Available The effect of selective PDE-I (vinpocetine, PDE-III (milrinone, CI-930, PDE-IV (rolipram, nitroquazone, and PDE-V (zaprinast isozyme inhibitors on TNF-α and IL-1β production from LPS stimulated human monocytes was investigated. The PDE-IV inhibitors caused a concentration dependent inhibition of TNF-α production, but only partially inhibited IL-1β at high concentrations. High concentrations of the PDE-III inhibitors weakly inhibited TNF-α, but had no effect on IL-1β production. PDE-V inhibition was associated with an augmentation of cytokine secretion. Studies with combinations of PDE isozyme inhibitors indicated that PDE-III and PDE-V inhibitors modulate rolipram's suppression of TNF production in an additive manner. These data confirm that TNF-α and IL-1β production from LPS stimulated human monocytes are differentially regulated, and suggest that PDE-IV inhibitors have the potential to suppress TNF levels in man.

  20. Antidiarrheal and Antispasmodic Activities of Buddleja polystachya are Mediated Through Dual Inhibition of Ca(++) Influx and Phosphodiesterase Enzyme.

    Science.gov (United States)

    Rehman, Najeeb-ur; Gilani, Anwarul-Hassan; Khan, Aslam; Nazneen, Maryam; El Gamal, Ali A; Fawzy, Ghada A; Al-Ati, Hanan Y; Abdel-kader, Maged S

    2015-08-01

    This study describes the antidiarrheal and antispasmodic activities of the hydro-alcoholic extract of Buddleja polystachya (Bp.Cr) with possible mode of action explored along with activity-directed fractionation. Bp.Cr and its aqueous (Bp.Aq) and organic fractions, petroleum ether (Bp.Pet), dichloromethane (Bp.DCM), ethylacetate (Bp.EtAc) and butanol (Bp.But), were tested using the in-vivo and in-vitro assays. The crude extract (100-300 mg/kg) showed 20 and 60% protection of castor oil-induced diarrhea in mice. In isolated rabbit jejunum, Bp.Cr like papaverine inhibited spontaneous and high K(+) (80 mM)-induced contractions equi-potently. In guinea-pig ileum, Bp.Cr showed a moderate spasmogenic effect. The activity-directed fractionation revealed that the spasmolytic activity was concentrated in the organic fractions and spasmogenic component in the aqueous fraction. Amongst the organic fractions, BP.DCM and Bp.Pet inhibited spontaneous and high K(+) -induced contractions equi-potently, while Bp.But, like verapamil was more potent against high K(+) . The crude extract and its organic fractions caused rightward shift in the Ca(++) -concentration response curves (CRCs), similar to verapamil, and all except Bp.But potentiated the isoprenaline-inhibitory CRCs to the left, similar to papaverine. The results of this study indicate that the crude extract of B. polystachya possesses antidiarrheal and antispasmodic activities, mediated possibly through dual inhibition of Ca(++) influx and phospodiesterase enzyme. Copyright © 2015 John Wiley & Sons, Ltd.

  1. Biochanin A, a Phytoestrogenic Isoflavone with Selective Inhibition of Phosphodiesterase 4, Suppresses Ovalbumin-Induced Airway Hyperresponsiveness

    Directory of Open Access Journals (Sweden)

    Wun-Chang Ko

    2011-01-01

    the serum and BALF, and enhanced the total IgG2a level in the serum of these mice. The PDE4H/PDE4L value of biochanin A was calculated as >35. Biochanin A did not influence xylazine/ketamine-induced anesthesia. Biochanin A (10~30 μM significantly reduced cumulative OVA (10~100 μg/mL-induced contractions in the isolated guinea pig trachealis, suggesting that it inhibits degranulation of mast cells. In conclusion, red clover containing biochanin A has the potential for treating allergic asthma and COPD.

  2. Structural asymmetry of phosphodiesterase-9, potential protonation of a glutamic acid, and role of the invariant glutamine.

    Directory of Open Access Journals (Sweden)

    Jing Hou

    2011-03-01

    Full Text Available PDE9 inhibitors show potential for treatment of diseases such as diabetes. To help with discovery of PDE9 inhibitors, we performed mutagenesis, kinetic, crystallographic, and molecular dynamics analyses on the active site residues of Gln453 and its stabilizing partner Glu406. The crystal structures of the PDE9 Q453E mutant (PDE9Q453E in complex with inhibitors IBMX and (S-BAY73-6691 showed asymmetric binding of the inhibitors in two subunits of the PDE9Q453E dimer and also the significant positional change of the M-loop at the active site. The kinetic analysis of the Q453E and E406A mutants suggested that the invariant glutamine is critical for binding of substrates and inhibitors, but is unlikely to play a key role in the differentiation between substrates of cGMP and cAMP. The molecular dynamics simulations suggest that residue Glu406 may be protonated and may thus explain the hydrogen bond distance between two side chain oxygens of Glu453 and Glu406 in the crystal structure of the PDE9Q453E mutant. The information from these studies may be useful for design of PDE9 inhibitors.

  3. Sildenafil and analogous phosphodiesterase type 5 (PDE-5) inhibitors in herbal food supplements sampled on the Dutch market

    NARCIS (Netherlands)

    Reeuwijk, N.M.; Venhuis, B.J.; Kaste, de D.; Hoogenboom, L.A.P.; Rietjens, I.; Martena, M.J.

    2013-01-01

    Herbal food supplements, claiming to enhance sexual potency, may contain deliberately added active pharmacological ingredients (APIs) that can be used for the treatment of erectile dysfunction (ED). The aim of this study was to determine whether herbal food supplements on the Dutch market indeed

  4. The phosphodiesterase 3 inhibitor cilostazol dilates large cerebral arteries in humans without affecting regional cerebral blood flow

    DEFF Research Database (Denmark)

    Birk, Steffen; Kruuse, Christina Rostrup; Petersen, Kenneth A

    2004-01-01

    in the middle cerebral arteries (VMCA) was measured with transcranial Doppler, and the superficial temporal and radial arteries diameters were measured with ultrasonography. During the 4-hour observation period, there was no effect on systolic blood pressure (P = 0.28), but diastolic blood pressure decreased...

  5. Investigation of a Putative Estrogen-Imprinting Gene, Phosphodiesterase Type IV Variant (PDE4D4), in Determining Prostate Cancer Risk

    National Research Council Canada - National Science Library

    Tang, Wan-Yee

    2007-01-01

    .... Estrogen imprinting of the prostate gland is believed to associate with an increased incidence of prostatic lesions including inflammation epithelial hyperplasia squamous metaplasia dysplasia and adenocarcinoma...

  6. Investigation of a Putative Estrogen-Imprinting Gene, Phosphodiesterase Type IV Variant (Pde4d4), in Determining Prostate Cancer Risk

    National Research Council Canada - National Science Library

    Tang, Wan-Yee

    2008-01-01

    .... Estrogen imprinting of the prostate gland is believed to associate with an increased incidence of prostatic lesions including inflammation, epithelial hyperplasia, squamous metaplasia, dysplasia and adenocarcinoma...

  7. Investigation of a Putative Estrogen-Imprinting Gene, Phosphodiesterase Type IV Variant (Pde4d4), in Determining Prostate Cancer Risk

    Science.gov (United States)

    2008-04-01

    arrays. Methods Mol Biol 2002;200:87–100. [78] Craig JM, Kraus J, Cremer T. Removal of repetitive sequences from FISH probes using PCR-assisted affinity...Worcester, MA), David Hepps, MD, and Lynn Birch for technical contributions. Figure 5. Alterations in PDE4D4 CpG methylation and gene expression in NbE-1

  8. Fragment-assisted hit investigation involving integrated HTS and fragment screening: Application to the identification of phosphodiesterase 10A (PDE10A) inhibitors.

    Science.gov (United States)

    Varnes, Jeffrey G; Geschwindner, Stefan; Holmquist, Christopher R; Forst, Janet; Wang, Xia; Dekker, Niek; Scott, Clay W; Tian, Gaochao; Wood, Michael W; Albert, Jeffrey S

    2016-01-01

    Fragment-based drug design (FBDD) relies on direct elaboration of fragment hits and typically requires high resolution structural information to guide optimization. In fragment-assisted drug discovery (FADD), fragments provide information to guide selection and design but do not serve as starting points for elaboration. We describe FADD and high-throughput screening (HTS) campaign strategies conducted in parallel against PDE10A where fragment hit co-crystallography was not available. The fragment screen led to prioritized fragment hits (IC50's ∼500μM), which were used to generate a hypothetical core scaffold. Application of this scaffold as a filter to HTS output afforded a 4μM hit, which, after preparation of a small number of analogs, was elaborated into a 16nM lead. This approach highlights the strength of FADD, as fragment methods were applied despite the absence of co-crystallographical information to efficiently identify a lead compound for further optimization. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Listeria monocytogenes PdeE, a phosphodiesterase that contributes to virulence and has hydrolytic activity against cyclic mononucleotides and cyclic dinucleotides

    Science.gov (United States)

    We have identified and partially characterized a putative HD domain hydrolase, LMOf2365_2464, which is highly expressed during listerial intracellular replication. LMOf2365_2464 is annotated as a putative HD domain-containing hydrolase. The ability of an isogenic mutant strain, F2365'2464, to adhere...

  10. cGMP inhibition of type 3 phosphodiesterase is the major mechanism by which C-type natriuretic peptide activates CFTR in the shark rectal gland

    NARCIS (Netherlands)

    H.R. de Jonge (Hugo); B.C. Tilly (Bernard); B.M. Hogema (Boris); D.J. Pfau (Daniel); C.A. Kelley (Catherine); M.H. Kelley (Megan); A.M. Melita (August); M.T. Morris (Montana); M.S. Viola (Maria); J.N. Forrest Jr. (John)

    2014-01-01

    textabstractThe in vitro perfused rectal gland of the dogfish shark (Squalus acanthias) and filter-grown monolayers of primary cultures of shark rectal gland (SRG) epithelial cells were used to analyze the signal transduction pathway by which C-type natriuretic peptide (CNP) stimulates chloride

  11. Phosphodiesterase inhibitor KMUP-3 displays cardioprotection via protein kinase G and increases cardiac output via G-protein-coupled receptor agonist activity and Ca2+ sensitization

    Directory of Open Access Journals (Sweden)

    Chung-Pin Liu

    2016-02-01

    Full Text Available KMUP-3 (7-{2-[4-(4-nitrobenzene piperazinyl]ethyl}-1, 3-dimethylxanthine displays cardioprotection and increases cardiac output, and is suggested to increase cardiac performance and improve myocardial infarction. To determine whether KMUP-3 improves outcomes in hypoperfused myocardium by inducing Ca2+ sensitization to oppose protein kinase (PKG-mediated Ca2+ blockade, we measured left ventricular systolic blood pressure, maximal rates of pressure development, mean arterial pressure and heart rate in rats, and measured contractility and expression of PKs/RhoA/Rho kinase (ROCKII in beating guinea pig left atria. Hemodynamic changes induced by KMUP-3 (0.5–3.0 mg/kg, intravenously were inhibited by Y27632 [(R-(+-trans-4-1-aminoethyl-N-(4-Pyridyl cyclohexane carboxamide] and ketanserin (1 mg/kg, intravenously. In electrically stimulated left guinea pig atria, positive inotropy induced by KMUP-3 (0.1–100μM was inhibited by the endothelial NO synthase (eNOS inhibitors N-nitro-l-arginine methyl ester (L-NAME and 7-nitroindazole, cyclic AMP antagonist SQ22536 [9-(terahydro-2-furanyl-9H-purin-6-amine], soluble guanylyl cyclase (sGC antagonist ODQ (1H-[1,2,4] oxadiazolo[4,3-a] quinoxalin-1-one, RhoA inhibitor C3 exoenzyme, β-blocker propranolol, 5-hydroxytryptamine 2A antagonist ketanserin, ROCK inhibitor Y27632 and KMUP-1 (7-{2-[4-(2-chlorobenzene piperazinyl]ethyl}-1, 3-dimethylxanthine at 10μM. Western blotting assays indicated that KMUP-3 (0.1–10μM increased PKA, RhoA/ROCKII, and PKC translocation and CIP-17 (an endogenous 17-kDa inhibitory protein activation. In spontaneous right atria, KMUP-3 induced negative chronotropy that was blunted by 7-nitroindazole and atropine. In neonatal myocytes, L-NAME inhibited KMUP-3-induced eNOS phosphorylation and RhoA/ROCK activation. In H9c2 cells, Y-27632 (50μM and PKG antagonist KT5823 [2,3,9,10,11,12-hexahydro-10R- methoxy-2,9-dimethyl-1-oxo-9S,12R-epoxy-1H-diindolo(1,2,3-fg:3′,2′,1′-kl pyrrolo(3,4-i(1,6benzodiazocine-10-carboxylic acid, methyl ester] (3μM reversed KMUP-3 (1–100μM-induced Ca2+-entry blockade. GPCR agonist activity of KMUP-3 appeared opposed to KMUP-1, and increased cardiac output via Ca2+ sensitization, and displayed cardioprotection via cyclic GMP/PKG-mediated myocardial preconditioning in animal studies.

  12. Does a single dose of the phosphodiesterase 4 inhibitor, cilomilast (15 mg), induce bronchodilation in patients with chronic obstructive pulmonary disease?

    NARCIS (Netherlands)

    Grootendorst, D. C.; Gauw, S. A.; Baan, R.; Kelly, J.; Murdoch, R. D.; Sterk, P. J.; Rabe, K. F.

    2003-01-01

    Maintenance treatment with PDE(4) inhibitor cilomilast improves FEV(1) in chronic obstructive pulmonary disease (COPD) patients. We investigated the acute bronchodilating effects of a single dose of cilomilast with or without concomitant administration of inhaled salbutamol and/or ipratropium

  13. Ayanin, a non-selective phosphodiesterase 1-4 inhibitor, effectively suppresses ovalbumin-induced airway hyperresponsiveness without affecting xylazine/ketamine-induced anesthesia.

    Science.gov (United States)

    Lee, Fei-Peng; Shih, Chwen-Ming; Shen, Hsin-Yi; Chen, Chien-Ming; Chen, Chi-Ming; Ko, Wun-Chang

    2010-06-10

    In recent in vitro reports, the IC(50) value of ayanin (quercetin-3,7,4'-O-trimethylether) was 2.2microM for inhibiting interleukin (IL)-4 production from purified basophils, and its therapeutic ratio was >19. Therefore, we were interested in investigating the effects on ovalbumin induced airway hyperresponsiveness in vivo, and to clarify its potential for treating asthma. Ayanin (30-100micromol/kg, orally (p.o.)) dose-dependently and significantly attenuated the enhanced pause (P(enh)) value induced by methacholine in sensitized and challenged mice. It also significantly suppressed the increases in total inflammatory cells, macrophages, lymphocytes, neutrophils, and eosinophils, and levels of cytokines, including IL-2, IL-4, IL-5, and tumor necrosis factor (TNF)-alpha in bronchoalveolar lavage fluid of these mice. However, at 100micromol/kg, it significantly enhanced the level of interferon (IFN)-gamma. In addition, ayanin (30-100micromol/kg, p.o.) dose-dependently and significantly suppressed total and OVA-specific immunoglobulin (Ig)E levels in the serum and bronchoalveolar lavage fluid, and enhanced the IgG(2a) level in serum of these mice. In the present results, ayanin did not affect xylazine/ketamine-induced anesthesia, suggesting that ayanin has few or no adverse effects, such as nausea, vomiting, and gastric hypersecretion. In conclusion, the above results suggest that ayanin may have the potential for use in treating allergic asthma.

  14. Synthesis of carbon-11-labeled imidazopyridine- and purine-thioacetamide derivatives as new potential PET tracers for imaging of nucleotide pyrophosphatase/phosphodiesterase 1 (NPP1).

    Science.gov (United States)

    Gao, Mingzhang; Wang, Min; Zheng, Qi-Huang

    2016-03-01

    The target tracer carbon-11-labeled imidazopyridine- and purine-thioacetamide derivatives, N-(3-[(11)C]methoxy-4-methoxyphenyl)-2-((5-methoxy-3H-imidazo[4,5-b]pyridin-2-yl)thio)acetamide (3-[(11)C]4a) and N-(4-[(11)C]methoxy-3-methoxyphenyl)-2-((5-methoxy-3H-imidazo[4,5-b]pyridin-2-yl)thio)acetamide (4-[(11)C]4a); 2-((6-amino-9H-purin-8-yl)thio)-N-(3-[(11)C]methoxy-4-methoxyphenyl)acetamide (3-[(11)C]8a) and 2-((6-amino-9H-purin-8-yl)thio)-N-(4-[(11)C]methoxy-3-methoxyphenyl)acetamide (4-[(11)C]8a), were prepared by O-[(11)C]methylation of their corresponding precursors with [(11)C]CH3OTf under basic condition (2N NaOH) and isolated by a simplified solid-phase extraction (SPE) method in 50-60% radiochemical yields based on [(11)C]CO2 and decay corrected to end of bombardment (EOB). The overall synthesis time from EOB was 23min, the radiochemical purity was >99%, and the specific activity at end of synthesis (EOS) was 185-555GBq/μmol. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Liquid chromatography-high resolution mass spectrometry (LC-HRMS) determination of stimulants, anorectic drugs and phosphodiesterase 5 inhibitors (PDE5I) in food supplements.

    Science.gov (United States)

    Strano-Rossi, Sabina; Odoardi, Sara; Castrignanò, Erika; Serpelloni, Giovanni; Chiarotti, Marcello

    2015-03-15

    The paper describes a liquid chromatography/high resolution mass spectrometry LC/HRMS method for the simultaneous identification and quantification of stimulants (ephedrines, caffeine, anorectic drugs such as phentermine, phendimetrazine, phenmetrazine, fenfluramine, benfluorex, mephentermine, fencanfamine, sibutramine) and PDE5I (sildenafil, vardenafil and tadalafil) in food supplements using a benchtop Orbitrap mass spectrometer. The mass detector, with a nominal resolving power of 100,000 (FWHM at m/z 200), operated in full scan mode in ESI positive ionization mode. Analytes were identified by retention times, accurate masses and correspondence of experimental and calculated isotopic patterns. The limits of detection (LOD) obtained varied from 1 to 25 ng g(-1) and limits of quantification (LOQ) were 50 ng g(-1) for all compounds. The method was linear for all the analytes in the ranges from 50 to 2000 ng g(-1), giving correlation coefficients>0.99. Accuracy (intended as %E) and repeatability (% CV) were always lower than 15%. The method was applied to the analysis of 36 dietary supplements, revealing the presence of ephedrine and/or pseudoephedrine in four of them, caffeine in eight of them and sildenafil in four of them. In one case, ephedrine was not reported on the label of the dietary supplement, as well as for caffeine in other two cases. A further confirmation of the analytes identity in positive samples was obtained through in-source fragmentation and comparison of the obtained fragments and their relative abundances with those from certified standards. As the acquisition mode is full scan, it would be also possible to re-process a previously acquired datafile for the investigation of untargeted analytes. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Cyclic adenosine monophosphate metabolism in synaptic growth, strength, and precision: neural and behavioral phenotype-specific counterbalancing effects between dnc phosphodiesterase and rut adenylyl cyclase mutations.

    Science.gov (United States)

    Ueda, Atsushi; Wu, Chun-Fang

    2012-03-01

    Two classic learning mutants in Drosophila, rutabaga (rut) and dunce (dnc), are defective in cyclic adenosine monophosphate (cAMP) synthesis and degradation, respectively, exhibiting a variety of neuronal and behavioral defects. We ask how the opposing effects of these mutations on cAMP levels modify subsets of phenotypes, and whether any specific phenotypes could be ameliorated by biochemical counter balancing effects in dnc rut double mutants. Our study at larval neuromuscular junctions (NMJs) demonstrates that dnc mutations caused severe defects in nerve terminal morphology, characterized by unusually large synaptic boutons and aberrant innervation patterns. Interestingly, a counterbalancing effect led to rescue of the aberrant innervation patterns but the enlarged boutons in dnc rut double mutant remained as extreme as those in dnc. In contrast to dnc, rut mutations strongly affect synaptic transmission. Focal loose-patch recording data accumulated over 4 years suggest that synaptic currents in rut boutons were characterized by unusually large temporal dispersion and a seasonal variation in the amount of transmitter release, with diminished synaptic currents in summer months. Experiments with different rearing temperatures revealed that high temperature (29-30°C) decreased synaptic transmission in rut, but did not alter dnc and wild-type (WT). Importantly, the large temporal dispersion and abnormal temperature dependence of synaptic transmission, characteristic of rut, still persisted in dnc rut double mutants. To interpret these results in a proper perspective, we reviewed previously documented differential effects of dnc and rut mutations and their genetic interactions in double mutants on a variety of physiological and behavioral phenotypes. The cases of rescue in double mutants are associated with gradual developmental and maintenance processes whereas many behavioral and physiological manifestations on faster time scales could not be rescued. We discuss factors that could contribute to the effectiveness of counterbalancing interactions between dnc and rut mutations for phenotypic rescue.

  17. Specificity of the Cyclic GMP-Binding Activity and of a Cyclic GMP-Dependent Cyclic GMP Phosphodiesterase in Dictyostelium discoideum

    NARCIS (Netherlands)

    Haastert, Peter J.M. van; Walsum, Hans van; Meer, Rob C. van der; Bulgakov, Roman; Konijn, Theo M.

    1982-01-01

    The nucleotide specificity of the cyclic GMP-binding activity in a homogenate of Dictyostelium discoideum was determined by competition of cyclic GMP derivatives with [8-3H] cyclic GMP for the binding sites. The results indicate that cyclic GMP is bound to the binding proteins by hydrogen bonds at

  18. Inhibition of cGMP-specific phosphodiesterase type 5 reduces sodium excretion and arterial blood pressure in patients with NaCl retention and ascites

    DEFF Research Database (Denmark)

    Thiesson, Helle C; Jensen, Boye L; Jespersen, Bente

    2005-01-01

    ANG II, and aldosterone concentrations significantly after 60 min. Plasma cGMP concentration was increased after 120 and 180 min, and urinary sodium excretion and mean arterial blood pressure were decreased significantly at 120 and 180 min. Plasma ANP concentration, GFR, and RBF did not change after...

  19. Design, optimization, and biological evaluation of novel keto-benzimidazoles as potent and selective inhibitors of phosphodiesterase 10A (PDE10A).

    Science.gov (United States)

    Hu, Essa; Kunz, Roxanne K; Chen, Ning; Rumfelt, Shannon; Siegmund, Aaron; Andrews, Kristin; Chmait, Samer; Zhao, Sharon; Davis, Carl; Chen, Hang; Lester-Zeiner, Dianna; Ma, Ji; Biorn, Christopher; Shi, Jianxia; Porter, Amy; Treanor, James; Allen, Jennifer R

    2013-11-14

    Our development of PDE10A inhibitors began with an HTS screening hit (1) that exhibited both high p-glycoprotein (P-gp) efflux ratios in rat and human and poor metabolic stability. On the basis of cocrystal structure of 1 in human PDE10A enzyme, we designed a novel keto-benzimidazole 26 with comparable PDE10A potency devoid of efflux liabilities. On target in vivo coverage of PDE10A in rat brain was assessed using our previously reported LC-MS/MS receptor occupancy (RO) technology. Compound 26 achieved 55% RO of PDE10A at 30 mg/kg po and covered PDE10A receptors in rat brain in a dose-dependent manner. Cocrystal structure of 26 in PDE10A confirmed the binding mode of the novel scaffold. Further optimization resulted in the identification of keto-benzimidazole 34, which showed an increased in vivo efficacy of 57% RO in rats at 10 mg/kg po and an improved in vivo rat clearance and oral bioavailability.

  20. A cAMP Biosensor-Based High-Throughput Screening Assay for Identification of Gs-Coupled GPCR Ligands and Phosphodiesterase Inhibitors

    DEFF Research Database (Denmark)

    Vedel, Line; Bräuner-Osborne, Hans; Mathiesen, Jesper Mosolff

    2015-01-01

    Cyclic adenosine 3',5'-monophosphate (cAMP) is an important second messenger, and quantification of intracellular cAMP levels is essential in studies of G protein-coupled receptors (GPCRs). The intracellular cAMP levels are regulated by the adenylate cyclase (AC) upon activation of either Gs- or ...... also observed for the other representative Gs-coupled GPCRs tested, GLP-1R and GlucagonR. The FRET-based cAMP biosensor assay is robust, reproducible, and inexpensive with good Z factors and is highly applicable for HTS....

  1. Tissue turnover of collagen type I, III and elastin is elevated in the PCLS model of IPF and can be restored back to vehicle levels using a phosphodiesterase inhibitor

    DEFF Research Database (Denmark)

    Hansen, Niels Ulrik Brandt; Karsdal, Morten Asser; Brockbank, Sarah

    2016-01-01

    .T., two days apart. The rats were euthanized fourteen days after the last dose. PCLS were made and cultured for 48 h in: medium, medium + 100 μM IBMX (PDE inhibitor), or medium + 10 μM GM6001 (MMP inhibitor). Turnover of type I collagen (P1NP, C1M), type III collagen (iP3NP, C3M) and elastin degradation...... to the culture medium (P ≤ 0.05 - P ≤ 0.0001). Sirius Red and Orcein staining confirmed the presence of collagen and elastin deposition in the lungs of the animals receiving BLM. Conclusions: The protein fingerprint technology allows the assessment of ECM remodeling markers in the BLM PCLS model. By combining...

  2. Phenotype overlap in Xylella fastidiosa is controlled by the cyclic di-GMP phosphodiesterase Eal in response to antibiotic exposure and diffusible signal factor-mediated cell-cell signaling.

    Science.gov (United States)

    de Souza, Alessandra A; Ionescu, Michael; Baccari, Clelia; da Silva, Aline M; Lindow, Steven E

    2013-06-01

    Eal is an EAL domain protein in Xylella fastidiosa homologous to one involved in resistance to tobramycin in Pseudomonas aeruginosa. EAL and HD-GYP domain proteins are implicated in the hydrolysis of the secondary messenger bis-(3'-5')-cyclic dimeric GMP (cyclic di-GMP). Cell density-dependent communication mediated by a Diffusible Signal Factor (DSF) also modulates cyclic di-GMP levels in X. fastidiosa, thereby controlling the expression of virulence genes and genes involved in insect transmission. The possible linkage of Eal to both extrinsic factors such as antibiotics and intrinsic factors such as quorum sensing, and whether both affect virulence, was thus addressed. Expression of eal was induced by subinhibitory concentrations of tobramycin, and an eal deletion mutant was more susceptible to this antibiotic than the wild-type strain and exhibited phenotypes similar to those of an rpfF deletion mutant blocked in DSF production, such as hypermotility, reduced biofilm formation, and hypervirulence to grape. Consistent with that, the rpfF mutant was more susceptible than the wild-type strain to tobramycin. Therefore, we propose that cell-cell communication and antibiotic stress can apparently lead to similar modulations of cyclic di-GMP in X. fastidiosa, resulting in similar phenotypes. However, the effect of cell density is dominant compared to that of antibiotic stress, since eal is suppressed by RpfF, which may prevent inappropriate behavioral changes in response to antibiotic stress when DSF accumulates.

  3. Discovery and Early Clinical Development of 2-{6-[2-(3,5-Dichloro-4-pyridyl)acetyl]-2,3-dimethoxyphenoxy}-N-propylacetamide (LEO 29102), a Soft-Drug Inhibitor of Phosphodiesterase 4 for Topical Treatment of Atopic Dermatitis

    DEFF Research Database (Denmark)

    Felding, Jakob; D. Sørensen, Morten; Poulsen, Tina D.

    2014-01-01

    mediated side effects. Here we describe our approach to circumvent this issue by applying a soft-drug concept in the design of a topically acting PDE4 inhibitor for treatment of dermatological diseases. We used a fast follower approach, starting from piclamilast. In particular, simultaneous introduction...

  4. Efficacy and gastrointestinal tolerability of ML3403, a selective inhibitor of p38 MAP kinase and CBS-3595, a dual inhibitor of p38 MAP kinase and phosphodiesterase 4 in CFA-induced arthritis in rats.

    Science.gov (United States)

    Koch, Diana A; Silva, Rodrigo B M; de Souza, Alessandra H; Leite, Carlos E; Nicoletti, Natália F; Campos, Maria M; Laufer, Stefan; Morrone, Fernanda B

    2014-03-01

    Mitogen-activated protein kinase (MAPK) p38 inhibitors have entered the clinical phase, although many of them have failed due to high toxicity and lack of efficacy. In the present study we compared the effects of the selective p38 inhibitor ML3403 and the dual p38-PDE4 inhibitor CBS-3595, on inflammatory and nociceptive parameters in a model of polyarthritis in rats. Male Wistar rats (180-200 g) were used for the complete Freund's adjuvant (CFA)-induced arthritis model and they were evaluated at 14-21 days. We also analysed the effects of these pharmacological tools on liver and gastrointestinal toxicity and on cytokine levels. Repeated CBS-3595 (3 mg/kg) or ML3403 (10 mg/kg) administration produced significant anti-inflammatory actions in the chronic arthritis model induced by CFA. CBS-3595 and ML3403 treatment also markedly reduced the production of the proinflammatory cytokine IL-6 in the paw tissue, whereas it widely increased the levels of the anti-inflammatory cytokine IL-10. Moreover, CBS-3595 produced partial anti-allodynic effects in the CFA model at 4 and 8 days after treatment. Notably, ML3403 and CBS-3595 did not show marked signs of hepatoxicity, as supported by unaltered histological observations in the liver sections. Finally, both compounds were safe in the gastrointestinal tract, according to evaluation of intestinal biopsies. CBS-3595 displayed a superior profile regarding its anti-inflammatory effects. Thus p38 MAPK/PDE4 blocking might well constitute a relevant strategy for the treatment of RA.

  5. Conversion of a heme-based oxygen sensor to a heme oxygenase by hydrogen sulfide: effects of mutations in the heme distal side of a heme-based oxygen sensor phosphodiesterase (Ec DOS)

    Czech Academy of Sciences Publication Activity Database

    Du, Y.; Liu, G.; Yan, Y.; Huang, D.; Luo, W.; Martínková, M.; Man, Petr; Shimizu, T.

    2013-01-01

    Roč. 26, č. 5 (2013), s. 839-852 ISSN 0966-0844 Institutional support: RVO:61388971 Keywords : Heme oxygenase * Heme protein * Hydrogen sulfide Subject RIV: CE - Biochemistry Impact factor: 2.689, year: 2013

  6. Interaction of divalent metal ions with Zn(2+)-glycerophosphocholine cholinephosphodiesterase from ox brain.

    Science.gov (United States)

    Lee, K J; Kim, M R; Kim, Y B; Myung, P K; Sok, D E

    1997-12-01

    The effect of divalent metal ions on the activity of glycerophosphocholine cholinephosphodiesterse from ox brain was examined. Zn(2+)- and Co(2+)-glycerophosphocholine cholinephosphodiesterases were prepared from the exposure of apoenzyme to Zn2+ and Co2+, respectively, and the properties of two metallo-phosphodiesterases were compared to those of native phosphodiesterase. Although two metallo-enzymes were similar in expressing Km value, optimum pH or sensitivity to Cu2+, they differed in the susceptibility to the inhibition by thiocholine or tellurite; while Co(2+)-phosphodiesterase was more sensitive to tellurites, Zn(2+)-phosphodiesterase was more susceptible to inhibition by thiocholine. In addition, Zn(2+)-phosphodiesterase was more thermo-stable than Co2+ enzyme. Separately, when properties of native phosphodiesterase were compared to those of each metallo-phosphodiesterase, native phosphodiesterase was found to be quite similar to Zn(2+)-phosphodiesterase in many respects. Even in thermo-stability, native enzyme resembled Zn(2+)-phosphodiesterase rather than Co(2+)-enzyme. Consistent with this, the stability of native phosphodiesterase was maintained in the presence of Zn2+, but not Co2+, Mn2+ was also as effective as Zn2+ in the stabilization of the enzyme. Noteworthy, the native enzyme was found to be inhibited competitively by Cu2+ with a Ki value of 20 microM, and its inhibitory action was antagonized effectively by Zn2+ or Co2+. Also, choline, another competitive inhibitor of the enzyme, appeared to antagonize the inhibitory action of Cu2+. Taken together, it is suggested that there may be multiple binding sites for divalent metal ions in the molecule of glycerophosphocholine cholinephosphodiesterase.

  7. Estudo clínico fase I de carbonato de lodenafila, um novo tipo de inibidor de fosfodiesterase 5 (PDE5), em voluntários saudáveis do sexo masculino = : A phase I clinical trial of lodenafil carbonate, a new phosphodiesterase type 5 (PDE5) inhibitor, in healthy male volunteers

    OpenAIRE

    Hilton Oliveira dos Santos Filho

    2013-01-01

    Resumo: Carbonato de Lodenafila é um novo tipo de inibidor de fosfodiesterase 5 (PDE5) utilizado no tratamento da disfunção erétil. O presente estudo foi realizado para avaliar a segurança, tolerabilidade e farmacocinética do carbonato de lodenafila após a administração de doses orais únicas ascendentes (de 1 a 100 mg) a voluntários saudáveis do sexo masculino (n = 33). O estudo foi um estudo clínico fase I, aberto, de escalonamento de dose, utilizando a administração de doses orais únicas de...

  8. Elvitegravir, Cobicistat, Emtricitabine, and Tenofovir

    Science.gov (United States)

    ... so that the medication will have a greater effect. Although the combination of elvitegravir, cobicistat, emtricitabine and ... Gengraf, Neoral, Sandimmune), sirolimus (Rapamune), and tacrolimus (Prograf); oxcarbazepine (Oxtellar XR, Trileptal); perphenazine; quetiapine (Seroquel); phosphodiesterase (PDE5) ...

  9. Tetomilast.

    LENUS (Irish Health Repository)

    O'Mahony, Seamus

    2012-02-03

    Otsuka is developing a once-daily oral formulation of the phosphodiesterase-4 inhibitor tetomilast for the potential treatment of ulcerative colitis (phase III) and chronic obstructive pulmonary disease (phase II).

  10. Dgroup: DG01062 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available ceptor antagonist, Phosphodiesterase (PDE) inhibitor, Xanthine cardiodiuretics; X...anthine bronchodilator; Cardiac diuretics ADORA1 [HSA:134] [KO:K04265] ADORA2A [HSA:135] [KO:K04266] PDE [HS

  11. Treatment of infertility in men with spinal cord injury

    DEFF Research Database (Denmark)

    Brackett, N.L.; Lynne, C.M.; El Dib, Hussein Ibrahim El Desouki Hussein

    2010-01-01

    Most men with spinal cord injury (SCI) are infertile. Erectile dysfunction, ejaculatory dysfunction and semen abnormalities contribute to the problem. Treatments for erectile dysfunction include phosphodiesterase type 5 inhibitors, intracavernous injections of alprostadil, penile prostheses...

  12. ATP-consuming and ATP-generating enzymes secreted by pancreas

    DEFF Research Database (Denmark)

    Yegutkin, Gennady G; Samburski, Sergei S; Jalkanen, Sirpa

    2006-01-01

    -generating enzymes in pancreatic juice, adenylate kinase, and NDP kinase, capable of sequentially phosphorylating AMP via ADP to ATP. Activities of nonspecific phosphatases, nucleotide pyrophosphatase/phosphodiesterases, and adenosine deaminase were negligible. Taken together, CCK-8 stimulation of pancreas causes...

  13. Guanine nucleotides stimulate hydrolysis of phosphatidyl inositol bis phosphate in human myelin membranes

    International Nuclear Information System (INIS)

    Boulias, C.; Moscarello, M.A.

    1989-01-01

    Phosphodiesterase activity was stimulated in myelin membranes in the presence of guanine nucleotide analogues. This activity was reduced in myelin membranes which had been adenosine diphosphate ribosylated in the presence of cholera toxin which ADP-ribosylated three proteins of Mr 46,000, 43,000 and 18,500. Aluminum fluoride treatment of myelin had the same stimulatory effects on phosphodiesterase activity as did the guanine nucleotides

  14. Erection capability is potentiated by long-term sildenafil treatment: role of blood flow-induced endothelial nitric-oxide synthase phosphorylation.

    Science.gov (United States)

    Musicki, Biljana; Champion, Hunter C; Becker, Robyn E; Liu, Tongyun; Kramer, Melissa F; Burnett, Arthur L

    2005-07-01

    Despite demonstrated clinical efficacy of sildenafil for the temporary treatment of erectile dysfunction, the possibility that sildenafil used long-term durably augments erectile ability remains unclear. We investigated whether continuous long-term administration of sildenafil at clinically relevant levels to aged rats "primes" the penis for improved erectile ability and involves nitric oxide (NO) or RhoA/Rho-kinase signaling pathways. In aged, but not young rats, sildenafil prolonged erection and increased the protein expressions of phosphorylated endothelial NO synthase (eNOS) at serine-1177 and phosphorylated Akt at serine-473 in penes. Only in the young rat penis, protein expressions of phosphodiesterase-5 and phosphomyosin phosphatase target subunit 1, a marker of Rho-kinase activity, were increased by sildenafil. Sildenafil inhibited phosphodiesterase-5 activity in penes of young and aged rats coincident with assayed free plasma levels of the drug equivalent to clinically therapeutic measurements. We conclude that erectile ability can be enhanced under preconditions of erectile impairment by long-term inhibition of phosphodiesterase-5 and that the effect is mediated by Akt-dependent eNOS phosphorylation. The lack of erectile ability enhancement in young rats by long-term phosphodiesterase-5 inhibition may relate to restrained NO signaling by phosphodiesterase-5 up-regulation, lack of incremental Akt and eNOS phosphorylation, and heightened Rho-kinase signaling in the penis.

  15. Women taking the “blue pill” (sildenafil citrate: such a big deal?

    Directory of Open Access Journals (Sweden)

    Lo Monte G

    2014-11-01

    Full Text Available Giuseppe Lo Monte, Angela Graziano, Isabella Piva, Roberto Marci Department of Morphology, Surgery, and Experimental Medicine, University of Ferrara, Ferrara, Italy Abstract: For years, phosphodiesterase type 5 inhibitors have been used for the treatment of erectile dysfunctions. Due to the similarities between male and female sexual response, several studies have assessed the effects of sildenafil citrate (Viagra® in women affected by female sexual arousal disorder. The results are still conflicting and the drug is not devoid of adverse effects. Furthermore, female sexual arousal disorder is a heterogeneous condition whose underlying causes are difficult to diagnose and appropriate treatment requires a thorough sexual, psychological, and medical history along with specialist consultations. The clinician should pursue a global approach to the patient with sexual difficulties, while non-hormonal treatment such as phosphodiesterase type 5 inhibitors (ie, sildenafil citrate should be kept as the last option. Keywords: phosphodiesterase type 5 inhibitors, female sexual arousal disorder (FSAD, sildenafil citrate

  16. Effects and mechanisms of action of sildenafil citrate in human chorionic arteries

    Directory of Open Access Journals (Sweden)

    Lynch Tadhg

    2009-04-01

    Full Text Available Abstract Objectives Sildenafil citrate, a specific phosphodiesterase-5 inhibitor, is increasingly used for pulmonary hypertension in pregnancy. Sildenafil is also emerging as a potential candidate for the treatment of intra-uterine growth retardation and for premature labor. Its effects in the feto-placental circulation are not known. Our objectives were to determine whether phosphodiesterase-5 is present in the human feto-placental circulation, and to characterize the effects and mechanisms of action of sildenafil citrate in this circulation. Study Design Ex vivo human chorionic plate arterial rings were used in all experiments. The presence of phosphodiesterase-5 in the feto-placental circulation was determined by western blotting and immunohistochemical staining. In a subsequent series of pharmacologic studies, the effects of sildenafil citrate in pre-constricted chorionic plate arterial rings were determined. Additional studies examined the role of cGMP and nitric oxide in mediating the effects of sildenafil. Results Phosphodiesterase-5 mRNA and protein was demonstrated in human chorionic plate arteries. Immunohistochemistry demonstrated phosphodiesterase-5 within the arterial muscle layer. Sildenafil citrate produced dose dependent vasodilatation at concentrations at and greater than 10 nM. Both the direct cGMP inhibitor methylene blue and the cGMP-dependent protein kinase inhibitor Rp-8-Br-PET-cGMPS significantly attenuated the vasodilation produced by sildenafil citrate. Inhibition of NO production with L-NAME did not attenuate the vasodilator effects of sildenafil. In contrast, sildenafil citrate significantly enhanced the vasodilation produced by the NO donor sodium nitroprusside. Conclusion Phosphodiesterase-5 is present in the feto-placental circulation. Sildenafil citrate vasodilates the feto-placental circulation via a cGMP dependent mechanism involving increased responsiveness to NO.

  17. Effects and mechanisms of action of sildenafil citrate in human chorionic arteries.

    LENUS (Irish Health Repository)

    Maharaj, Chrisen H

    2009-01-01

    OBJECTIVES: Sildenafil citrate, a specific phosphodiesterase-5 inhibitor, is increasingly used for pulmonary hypertension in pregnancy. Sildenafil is also emerging as a potential candidate for the treatment of intra-uterine growth retardation and for premature labor. Its effects in the feto-placental circulation are not known. Our objectives were to determine whether phosphodiesterase-5 is present in the human feto-placental circulation, and to characterize the effects and mechanisms of action of sildenafil citrate in this circulation. STUDY DESIGN: Ex vivo human chorionic plate arterial rings were used in all experiments. The presence of phosphodiesterase-5 in the feto-placental circulation was determined by western blotting and immunohistochemical staining. In a subsequent series of pharmacologic studies, the effects of sildenafil citrate in pre-constricted chorionic plate arterial rings were determined. Additional studies examined the role of cGMP and nitric oxide in mediating the effects of sildenafil. RESULTS: Phosphodiesterase-5 mRNA and protein was demonstrated in human chorionic plate arteries. Immunohistochemistry demonstrated phosphodiesterase-5 within the arterial muscle layer. Sildenafil citrate produced dose dependent vasodilatation at concentrations at and greater than 10 nM. Both the direct cGMP inhibitor methylene blue and the cGMP-dependent protein kinase inhibitor Rp-8-Br-PET-cGMPS significantly attenuated the vasodilation produced by sildenafil citrate. Inhibition of NO production with L-NAME did not attenuate the vasodilator effects of sildenafil. In contrast, sildenafil citrate significantly enhanced the vasodilation produced by the NO donor sodium nitroprusside. CONCLUSION: Phosphodiesterase-5 is present in the feto-placental circulation. Sildenafil citrate vasodilates the feto-placental circulation via a cGMP dependent mechanism involving increased responsiveness to NO.

  18. Sildenafil enhances systolic adaptation, but does not prevent diastolic dysfunction, in the pressure-loaded right ventricle

    NARCIS (Netherlands)

    Borgdorff, Marinus A. J.; Bartelds, Beatrijs; Dickinson, Michael G.; Weij, Michel; Zandvoort, Andre; Sillje, Herman H. W.; Steendijk, Paul; de Vroomen, Maartje; Berger, Rolf M. F.; Boersma, B.

    Right ventricular (RV) failure due to pressure or volume overload is a major risk factor for early mortality in congenital heart disease and pulmonary hypertension, but currently treatments are lacking. We aimed to demonstrate that the phosphodiesterase 5A inhibitor sildenafil can prevent adverse

  19. Effect of PDE5 inhibition on the modulation of sympathetic α-adrenergic vasoconstriction in contracting skeletal muscle of young and older recreationally active humans

    DEFF Research Database (Denmark)

    Nyberg, Michael Permin; Piil, Peter Bergmann; Egelund, Jon

    2015-01-01

    Aging is associated with an altered regulation of blood flow to contracting skeletal muscle; however, the precise mechanisms remain unclear. We recently demonstrated that inhibition of cGMP-binding phosphodiesterase 5 (PDE5) increased blood flow to contracting skeletal muscle of older but not you...

  20. Main: 1JH6 [RPSD[Archive

    Lifescience Database Archive (English)

    Full Text Available sterase; Chain: A, B; Engineered: Yes Hydrolase 3.1.4.- (Cyclic Phosphodiesterase) A.Hofmann, M.Grella, I.Bo...tos, W.Filipowicz, A.Wlodawer A.Hofmann, M.Grella, I.Botos, W.Filipowicz, A.Wloda

  1. Syntetické modely metaloenzymů katalyzující štěpení fosfodiesterové vazby

    Czech Academy of Sciences Publication Activity Database

    Bím, Daniel; Rulíšek, Lubomír; Hodačová, J.

    2015-01-01

    Roč. 109, č. 9 (2015), s. 658-665 ISSN 0009-2770 Institutional support: RVO:61388963 Keywords : synthetic models of phosphodiesterases * metalloenzymes * phosphate ester bond cleavage Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 0.279, year: 2015

  2. N Termini of apPDE4 Isoforms Are Responsible for Targeting the Isoforms to Different Cellular Membranes

    Science.gov (United States)

    Jang, Deok-Jin; Park, Soo-Won; Lee, Jin-A; Lee, Changhoon; Chae, Yeon-Su; Park, Hyungju; Kim, Min-Jeong; Choi, Sun-Lim; Lee, Nuribalhae; Kim, Hyoung; Kaang, Bong-Kiun

    2010-01-01

    Phosphodiesterases (PDEs) are known to play a key role in the compartmentalization of cAMP signaling; however, the molecular mechanisms underlying intracellular localization of different PDE isoforms are not understood. In this study, we have found that each of the supershort, short, and long forms of apPDE4 showed distinct localization in the…

  3. Radical prostatectomy

    DEFF Research Database (Denmark)

    Fode, Mikkel; Sønksen, Jens; Jakobsen, Henrik

    2014-01-01

    surgery and at follow-up and they were asked to report their use of pads/diapers. Potency was defined as an IIEF-5 score of at least 17 with or without phosphodiesterase-5 inhibitors. Patients using up to one pad daily for security reasons only were considered continent. Positive surgical margins, blood...

  4. Toward Personalized Sexual Medicine (Part 2) : Testosterone Combined with a PDE5 Inhibitor Increases Sexual Satisfaction in Women with HSDD and FSAD, and a Low Sensitive System for Sexual Cues

    NARCIS (Netherlands)

    Poels, S.; Bloemers, J.; van Rooij, K.; Goldstein, I.; Gerritsen, J.; van Ham, D.; van Mameren, F.; Chivers, M.; Everaerd, W.; Koppeschaar, H.; Olivier, B.; Tuiten, A.

    INTRODUCTION: Low sexual desire in women may result from a relative insensitivity of the brain for sexual cues. Administration of sublingual 0.5 mg testosterone (T) increases the sensitivity of the brain to sexual cues. Sexual stimulation in the brain is necessary for phosphodiesterase type 5

  5. Does tadalafil prevent erectile dysfunction in patients undergoing radiation therapy for prostate cancer?

    NARCIS (Netherlands)

    L. Incrocci (Luca)

    2014-01-01

    textabstractA recently published paper addressed the interesting topic of prevention of erectile dysfunction (ED) with tadalafil, a phosphodiesterase-type 5 inhibitor (PDE5i) in patients undergoing radiation therapy for localized prostate cancer. [1]Tadalafil 5 mg or placebo was

  6. The pharmacological management of erectile dysfunction – Update ...

    African Journals Online (AJOL)

    Erectile dysfunction (ED) is a trivial condition with a prevailing incidence worldwide. Phosphodiesterase-5 inhibitors (PDE-5) have revolutionised the treatment of ED and are regarded as one of the most successful drug groups in modern medicine. Generally PDE-5 inhibitors are well tolerated and the incidence of ...

  7. Mænd med rejsningsbesvær efter radikal prostatektomi bør behandles efter sædvanlige retningslinjer

    DEFF Research Database (Denmark)

    Fode, Mikkel; Hansen, Rikke Bølling; Maigaard, Thomas

    2014-01-01

    Penile rehabilitation programmes aim to improve long-term sexual function after nerve-sparing radical prostatectomy. Programmes aim to improve cavernous oxygenation to avoid structural damage in penile tissue. Especially, daily use of phosphodiesterase type 5 (PDE5) inhibitors has been studied. T......, urethral suppositories and penile implants....

  8. Mænd med rejsningsbesvær efter radikal prostatektomi bør behandles efter sædvanlige retningslinjer

    DEFF Research Database (Denmark)

    Fode, Mikkel; Hansen, Rikke Bølling; Maigaard, Thomas

    2015-01-01

    Penile rehabilitation programmes aim to improve long-term sexual function after nerve-sparing radical prostatectomy. Programmes aim to improve cavernous oxygenation to avoid structural damage in penile tissue. Especially, daily use of phosphodiesterase type 5 (PDE5) inhibitors has been studied. T......, urethral suppositories and penile implants....

  9. In Vitro Evaluation of Biofilm Dispersal as a Therapeutic Strategy To Restore Antimicrobial Efficacy

    DEFF Research Database (Denmark)

    Roizman, Dan; Vidaillac, Celine; Givskov, Michael

    2017-01-01

    As a proof-of-concept study, the direct impact of biofilm dispersal on the in vitro efficacy of imipenem and tobramycin was evaluated against 3-day-old biofilms of Pseudomonas aeruginosa. Arabinose induction of biofilm dispersal via activation of the phosphodiesterase YhjH in the P. aeruginosa en...

  10. Multiple diguanylate cyclase-coordinated regulation of pyoverdine synthesis in Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Chen, Yicai; Yuan, Mingjun; Mohanty, Anee

    2015-01-01

    The nucleotide signalling molecule bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) plays an essential role in regulating microbial virulence and biofilm formation. C-di-GMP is synthesized by diguanylate cyclase (DGC) enzymes and degraded by phosphodiesterase (PDE) enzymes. One...

  11. Otezla, Warts and All, Racks Up Sales and Eyes Blockbuster Status.

    Science.gov (United States)

    Reinke, Thomas

    2017-10-01

    Otezla-the generic name is apremilast-also exploited a new mechanism of action as the first inhibitor of phosphodiesterase 4 (PDE4) that results in increased expression of both anti-inflammatory proteins and reduced expression of their pro-inflammatory counterparts.

  12. Genomewide Association Study of African Children Identifies Association of SCHIP1 and PDE8A with Facial Size and Shape

    Czech Academy of Sciences Publication Activity Database

    Cole, J.B.; Manyama, M.; Kimwaga, E.; Mathayo, J.; Larson, J.R.; Liberton, D.K.; Lukowiak, K.; Ferrara, T.M.; Riccardi, S.L.; Li, M.; Mio, W.; Procházková, Michaela; Williams, T.; Li, H.; Jones, K. L.; Klein, O. D.; Santorico, S.A.; Hallgrimsson, B.; Spritz, R.A.

    2016-01-01

    Roč. 12, č. 8 (2016), č. článku e1006174. ISSN 1553-7404 Institutional support: RVO:68378050 Keywords : cause char-syndrome * wide association * phosphodiesterase 8a * heritability * recognition * mutations * allometry * variants * parents Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 6.100, year: 2016

  13. Gclust Server: 120999 [Gclust Server

    Lifescience Database Archive (English)

    Full Text Available 120999 CME_CMG087C Cluster Sequences Related Sequences(20) 685 similar to lysosomal... sphingomyelin phosphodiesterase 1 1.00e-99 14.29 0.0 0.0 0.0 0.0 0.0 Show 120999 Cluster ID 120999 Sequence

  14. Pharmacotherapy of erectile dysfunction: Current standards

    Directory of Open Access Journals (Sweden)

    Kew-Kim Chew

    2006-01-01

    Full Text Available Pharmacotherapy is currently the therapeutic option of choice for erectile dysfunction. Comprising mainly intracavernosal injection therapy using alprostadil or alprostadil combined with phentolamine and/or papaverine and oral phosphodiesterase-5 inhibitors, it is safe and effective if appropriately prescribed and administered. The medications in current use produce satisfactory erectile responses by enhancing cavernosal vasodilatation mainly through their ability to promote relaxation of the smooth muscle cells in the corpora cavernosa involving the synthesis and activity of nitric oxide via the cyclic guanosine monophosphate and cyclic adenosine monophosphate biochemical pathways. The main side-effects and complications of intracavernosal injections are postinjection pain, prolonged erections, priapism and penile fibrosis. There may be a variety of side-effects with phosphodiesterase-5 inhibition but these are usually inconsequential. Recent serious ill health and the need for ongoing long-acting nitrate therapy or frequent use of short-acting nitrates for angina are absolute contraindications to the use of phosphodiesterase-5 inhibitors. Caution has to be exercised in prescribing phosphodiesterase-5 inhibitors for patients with impaired renal or hepatic functions or receiving multi-drug therapy for any systemic disease. All patients presenting with erectile dysfunction should be investigated and treated for cardiovascular risk factors. They should also be counseled regarding lifestyle factors particularly healthy balanced diet, regular physical exercise and inappropriate social habits.

  15. Sildenafil does not influence hepatic venous pressure gradient in patients with cirrhosis

    DEFF Research Database (Denmark)

    Clemmesen, Jens-Otto; Giraldi, Annamaria; Ott, Peter

    2008-01-01

    AIM: To investigate if sildenafil increases splanchnic blood flow and changes the hepatic venous pressure gradient (HVPG) in patients with cirrhosis. Phosphodiesterase type-5 inhibitors are valuable in the treatment of erectile dysfunction and pulmonary hypertension in patients with end-stage liver...

  16. Inhibition of PAF-induced expression of CD11b and shedding of L-selectin on human neutrophils and eosinophils by the type IV selective PDE inhibitor, rolipram

    NARCIS (Netherlands)

    Dijkhuizen, B; deMonchy, JGR; Dubois, AEJ; Gerritsen, J; Kauffman, HF

    We quantitatively determined whether the selective phosphodiesterase (PDE) inhibitor, rolipram, inhibits changes in the adhesion molecules CD11b and L-selectin on platelet-activating factor (PAF)-stimulated human neutrophils and eosinophils in vitro. Incubations were performed in human whole blood

  17. Acute dysphonia secondary to vocal fold hemorrhage after vardenafil use.

    Science.gov (United States)

    Singh, Vikas; Cohen, Seth M; Rousseau, Bernard; Noordzij, J Pieter; Garrett, C Gaelyn; Ossoff, Robert H

    2010-06-01

    Owing to their vasodilatory effects, the phosphodiesterase-5 inhibitors have become widely used for the treatment of erectile dysfunction. Among the reported adverse events of these agents are epistaxis, variceal bleeding, intracranial hemorrhage, and hemorrhoidal bleeding. We report a case of vocal fold hemorrhage that occurred after vardenafil use in a 31-year-old man who was a professional singer.

  18. Beneficial contribution of the arbuscular mycorrhizal fungus, Rhizophagus irregularis, in the protection of Medicago truncatula roots against benzo[a]pyrene toxicity.

    Science.gov (United States)

    Lenoir, Ingrid; Fontaine, Joël; Tisserant, Benoît; Laruelle, Frédéric; Lounès-Hadj Sahraoui, Anissa

    2017-07-01

    Arbuscular mycorrhizal fungi are able to improve plant establishment in polluted soils but little is known about the genes involved in the plant protection against pollutant toxicity by mycorrhization, in particular in the presence of polycyclic aromatic hydrocarbons (PAH). The present work aims at studying in both symbiotic partners, Medicago truncatula and Rhizophagus irregularis: (i) expression of genes putatively involved in PAH tolerance (MtSOD, MtPOX, MtAPX, MtGST, MtTFIIS, and MtTdp1α), (ii) activities of antioxidant (SOD, POX) and detoxification (GST) enzymes, and (iii) H 2 O 2 and the heavy PAH, benzo[a]pyrene (B[a]P) accumulation. In the presence of B[a]P, whereas induction of the enzymatic activities was detected in R. irregularis and non-mycorrhizal roots as well as upregulation of the gene expressions in the non-mycorrhizal roots, downregulation of the gene expressions and decrease of enzyme activities were observed in mycorrhizal roots. Moreover, B[a]P increased H 2 O 2 production in non-mycorrhizal roots and in R. irregularis but not in mycorrhizal roots. In addition, a lower B[a]P bioaccumulation in mycorrhizal roots was measured in comparison with non-mycorrhizal roots. Being less affected by pollutant toxicity, mycorrhizal roots did not activate any defense mechanism either at the gene expression regulation level or at the enzymatic level.

  19. Cyclic AMP system in muscle tissue during prolonged hypokinesia

    Science.gov (United States)

    Antipenko, Y. A.; Bubeyev, Y. A.; Korovkin, B. F.; Mikhaleva, N. P.

    1980-01-01

    Components of the cyclic Adenosine-cyclic-35-monophosphate (AMP) system in the muscle tissue of white rats were studied during 70-75 days of hypokinesia, created by placing the animals in small booths which restricted their movements, and during the readaptation period. In the initial period, cyclic AMP levels and the activities of phosphodiesterase and adenylate cyclase in muscle tissue were increased. The values for these indices were roughly equal for controls and experimental animals during the adaptation period, but on the 70th day of the experiment cAMP levels dropped, phosphodiesterase activity increased, and the stimulative effect of epinephrine on the activity of adenylate cyclase decreased. The indices under study normalized during the readaptation period.

  20. Effects of cholera toxin and isobutylmethylxanthine on growth of human fibroblasts

    International Nuclear Information System (INIS)

    Espinoza, B.; Wharton, W.

    1986-01-01

    Cholera toxin produced a dose-dependent decrease in the restimulation of G 0 /G 1 traverse in density-arrested human fibroblasts but did not inhibit the stimulation of cells arrested in G 0 after serum starvation at low density. In addition, cholera toxin did not inhibit the proliferation of sparse logarithmically growing human fibroblasts, even when low concentrations of the phosphodiesterase inhibitor isobutylmethylxanthine (IBMX) were also present. However, the final density to which sparse cells grew was limited by cholera toxin, when added either alone or together with low concentrations of IBMX. In contrast, high concentrations of the phosphodiesterase inhibitor alone produced a profound inhibition in the growth of sparse human fibrobasts. IBMX produced an inhibition both in the G 1 and in the G 2 phases of the cell cycle by a mechanism(s) that was not related to the magnitude of the increases in adenosine 3,5-cyclic monophosphate concentrations

  1. Repair of DNA treated with γ-irradiation and chemical carcinogens. Comprehensive report of entire period of ERDA support from June 1, 1975--January 15, 1978

    International Nuclear Information System (INIS)

    Goldthwait, D.A.

    1978-01-01

    A partially purified enzyme fraction isolated from E. coli showed an N-glycosidase activity as well as a phosphodiesterase activity on DNA treated with methylnitrosourea, and with 7-bromomethylbenz(a)anthracene and a phosphodiesterase activity against γ-irradiated DNA. Both 0-6 methyl guanine and 3-methyladenine were released from DNA treated with MNU; the adenine and guanine derivatives from the DNA treated with 7-bromomethyl-12-methylbenz(a)anthracene were also liberated. Progress is also reported on studies on Endonucleases II and VI and Exonuclease III of E. coli; methods for assay and for synthesis of substrates; attempts at purification of repair enzymes from mammalian tissues; and β-propiolactone reactions with deoxynucleosides and with DNA

  2. Women taking the "blue pill" (sildenafil citrate): such a big deal?

    Science.gov (United States)

    Lo Monte, Giuseppe; Graziano, Angela; Piva, Isabella; Marci, Roberto

    2014-01-01

    For years, phosphodiesterase type 5 inhibitors have been used for the treatment of erectile dysfunctions. Due to the similarities between male and female sexual response, several studies have assessed the effects of sildenafil citrate (Viagra(®)) in women affected by female sexual arousal disorder. The results are still conflicting and the drug is not devoid of adverse effects. Furthermore, female sexual arousal disorder is a heterogeneous condition whose underlying causes are difficult to diagnose and appropriate treatment requires a thorough sexual, psychological, and medical history along with specialist consultations. The clinician should pursue a global approach to the patient with sexual difficulties, while non-hormonal treatment such as phosphodiesterase type 5 inhibitors (ie, sildenafil citrate) should be kept as the last option.

  3. Women taking the “blue pill” (sildenafil citrate): such a big deal?

    Science.gov (United States)

    Lo Monte, Giuseppe; Graziano, Angela; Piva, Isabella; Marci, Roberto

    2014-01-01

    For years, phosphodiesterase type 5 inhibitors have been used for the treatment of erectile dysfunctions. Due to the similarities between male and female sexual response, several studies have assessed the effects of sildenafil citrate (Viagra®) in women affected by female sexual arousal disorder. The results are still conflicting and the drug is not devoid of adverse effects. Furthermore, female sexual arousal disorder is a heterogeneous condition whose underlying causes are difficult to diagnose and appropriate treatment requires a thorough sexual, psychological, and medical history along with specialist consultations. The clinician should pursue a global approach to the patient with sexual difficulties, while non-hormonal treatment such as phosphodiesterase type 5 inhibitors (ie, sildenafil citrate) should be kept as the last option. PMID:25422584

  4. Biofilm formation and antibiotic production in Ruegeria mobilis are influenced by intracellular concentrations of cyclic dimeric guanosinmonophosphate

    DEFF Research Database (Denmark)

    D'Alvise, Paul; Magdenoska, Olivera; Melchiorsen, Jette

    2014-01-01

    species Ruegeria mobilis are associated with intracellular concentrations of the signal compound cyclic dimeric guanosinmonophosphate (c-di-GMP), which in bacteria regulates transitions between motile and sessile life stages. Genes for diguanylate cyclases and phosphodiesterases, which are involved in c-di-GMP...... signalling, were found in the genome of R. mobilis strain F1926. Ion pair chromatography-tandem mass spectrometry revealed 20-fold higher c-di-GMP concentrations per cell in biofilm-containing cultures than in planktonic cells. An introduced diguanylate cyclase gene increased c-di-GMP and enhanced biofilm...... formation and production of the potent antibiotic tropodithietic acid (TDA). An introduced phosphodiesterase gene decreased c-di-GMP and reduced biofilm formation and TDA production. tdaC, a key gene for TDA biosynthesis, was expressed only in attached or biofilm-forming cells, and expression was induced...

  5. Distribution in rat tissues of modulator-binding protein of particulate nature

    International Nuclear Information System (INIS)

    Sobue, K.; Muramoto, Y.; Kakiuchi, S.; Yamazaki, R.

    1979-01-01

    Studies on Ca 2+ -activatable cyclic nucleotide phosphodiesterase led to the discovery of a protein modulator that is required for the activation of this enzyme by Ca 2+ . Later, this protein has been shown to cause the Ca 2+ -dependent activation of several enzymes that include phosphodiesterase, adenylate cyclase, a protein kinase from muscles, phosphorylase b kinase, actomyosin ATPase, membranous ATPase from erythrocytes and nerve synapses. Thus, modulator protein appears to be an intracellular mediator of actions of Ca 2+ . The present work shows the distribution of this particulate modulator-binding component in rat tissues. This paper also describes the labeling of modulator protein with tritium without deteriorating its biological activities and application of this 3 H-modulator protein to the determination of the Ca ++ dependent binding of modulator protein with membranous protein. This technique proves to be useful in studying enzymes or proteins whose functions are regulated by Ca ++ /modulator protein system. (Auth.)

  6. Enhancement of fracture healing in the rat, modulated by compounds that stimulate inducible nitric oxide synthase

    OpenAIRE

    Rajfer, R. A.; Kilic, A.; Neviaser, A. S.; Schulte, L. M.; Hlaing, S. M.; Landeros, J.; Ferrini, M. G.; Ebramzadeh, E.; Park, S-H.

    2017-01-01

    Objectives We investigated the effects on fracture healing of two up-regulators of inducible nitric oxide synthase (iNOS) in a rat model of an open femoral osteotomy: tadalafil, a phosphodiesterase inhibitor, and the recently reported nutraceutical, COMB-4 (consisting of L-citrulline, Paullinia cupana, ginger and muira puama), given orally for either 14 or 42 days. Materials and Methods Unilateral femoral osteotomies were created in 58 male rats and fixed with an intramedullary compression na...

  7. New Drugs and Treatment Targets in Psoriasis

    DEFF Research Database (Denmark)

    Kofoed, Kristian; Skov, Lone; Zachariae, Claus

    2015-01-01

    , and phosphodiesterase inhibitors. We review published clinical trials, and conference abstracts presented during the last years, concerned with new drugs under development for the treatment of psoriasis. In conclusion, our psoriasis armamentarium will be filled with several new effective therapeutic options the coming...... years. We need to be aware of the limitations of drug safety data when selecting new novel treatments. Monitoring and clinical registries are still important tools....

  8. Microgravity changes in heart structure and cyclic-AMP metabolism

    Science.gov (United States)

    Philpott, D. E.; Fine, A.; Kato, K.; Egnor, R.; Cheng, L.

    1985-01-01

    The effects of microgravity on cardiac ultrastructure and cyclic AMP metabolism in tissues of rats flown on Spacelab 3 are reported. Light and electron microscope studies of cell structure, measurements of low and high Km phosphodiesterase activity, cyclic AMP-dependent protein kinase activity, and regulatory subunit compartmentation show significant deviations in flight animals when compared to ground controls. The results indicate that some changes have occurred in cellular responses associated with catecholamine receptor interactions and intracellular signal processing.

  9. AFRRI (Armed Forces Radiobiology Research Institute) Reports, October, November, December 1986

    Science.gov (United States)

    1986-12-01

    thermal neutron fluence. Blocks of metallic bismuth surround- ing the foam dewar degraded the fission neutron spectrum and attenuated the fission y...in gastric and duodenal mucosa of healthy subjects and duodenal ulcer patients: effects of aspirin and paracetamol . Gut 1981; 22:283...phosphodiesterase (02 Units) or spiked with known quantities of cAMP or cGMP. Nucleotides present in the samples were degraded more than 93 per cent by

  10. Neutral Sphingomyelinase (SMPD3) Deficiency Causes a Novel Form of Chondrodysplasia and Dwarfism That Is Rescued by Col2A1-Driven smpd3 Transgene Expression

    OpenAIRE

    Stoffel, Wilhelm; Jenke, Britta; Holz, Barbara; Binczek, Erika; Günter, Robert Heinz; Knifka, Jutta; Koebke, Jürgen; Niehoff, Anja

    2007-01-01

    Neutral sphingomyelinase SMPD3 (nSMase2), a sphingomyelin phosphodiesterase, resides in the Golgi apparatus and is ubiquitously expressed. Gene ablation of smpd3 causes a generalized prolongation of the cell cycle that leads to late embryonic and juvenile hypoplasia because of the SMPD3 deficiency in hypothalamic neurosecretory neurons. We show here that this novel form of combined pituitary hormone deficiency is characterized by the perturbation of the hypothalamus-pituitary growth axis, ass...

  11. Non pigmenting mucosal fixed drug eruption due to tadalafil: A report of two cases

    Directory of Open Access Journals (Sweden)

    Sudip Das

    2014-01-01

    Full Text Available Various ′sex-stimulant′ medicines with fancy names and attractive packaging are available over the counter. Most contain phosphodiesterase 5 inhibitors in various strengths, often with herbal additions. These drugs are used erratically by the lay public, driven by folklore that such usage leads to increase in the length, girth or firmness of the penis. Such indiscriminate use by an otherwise healthy population leads to undue side effects.

  12. Continuous Intravenous Milrinone Therapy in Pediatric Outpatients

    OpenAIRE

    Curley, Michelle; Liebers, Jill; Maynard, Roy

    2017-01-01

    Milrinone is a phosphodiesterase 3 inhibitor with both positive inotropic and vasodilator properties. Administered as a continuous infusion, milrinone is indicated for the short-term treatment of patients with acute decompensated heart failure. Despite limited data supporting long-term milrinone therapy in adults with congestive heart failure, children managed as outpatients may benefit from continuous milrinone as a treatment for cardiac dysfunction, as a destination therapy for cardiac tran...

  13. Heart Protection by Combination Therapy with Esmolol and Milrinone at Late-Ischemia and Early Reperfusion

    OpenAIRE

    Huang, Ming-He; Wu, Yewen; Nguyen, Vincent; Rastogi, Saurabh; McConnell, Bradley K.; Wijaya, Cori; Uretsky, Barry F.; Poh, Kian-Keong; Tan, Huay-Cheem; Fujise, Kenichi

    2011-01-01

    Introduction The present study determined whether late-ischemia/early reperfusion therapy with the β1-adrenergic receptor (AR) blocker esmolol and phosphodiesterase III inhibitor milrinone reduced left ventricular (LV) myocardial infarct size (IS). Methods and Results In an ischemia/reperfusion rat model (30-min ischemia/4-hr reperfusion), esmolol, milrinone or esmolol + milrinone were intravenous (IV) infused over 10 min (from the last 5min of ischemia to the first 5min of reperfusion). LV-I...

  14. [Acute monocular loss of vision : Differential diagnostic considerations apart from the internistic etiological clarification].

    Science.gov (United States)

    Rickmann, A; Macek, M A; Szurman, P; Boden, K

    2017-08-03

    We report the case of acute painless monocular loss of vision in a 53-year-old man. An interdisciplinary etiological evaluation remained without pathological findings with respect to arterial branch occlusion. A reevaluation of the patient history led to a possible association with the administration of phosphodiesterase type 5 inhibitor (PDE5 inhibitor). A critical review of the literature on PDE5 inhibitor administration with ocular participation was performed.

  15. Sildenafil does not influence hepatic venous pressure gradient in patients with cirrhosis

    DEFF Research Database (Denmark)

    Clemmesen, J.O.; Giraldi, A.; Ott, P.

    2008-01-01

    AIM: To investigate if sildenafil increases splanchnic blood flow and changes the hepatic venous pressure gradient (HVPG) in patients with cirrhosis. Phosphodiesterase type-5 inhibitors are valuable in the treatment of erectile dysfunction and pulmonary hypertension in patients with end-stage liv...... type-5 inhibitor sildenafil, the present study could not demonstrate any clinical relevant influence on splanichnic blood flow, oxygen consumption or the HVPG Udgivelsesdato: 2008/10/28...

  16. Sildenafil does not influence hepatic venous pressure gradient in patients with cirrhosis

    DEFF Research Database (Denmark)

    Clemmesen, Jens-Otto; Giraldi, Annamaria; Ott, Peter

    2008-01-01

    AIM: To investigate if sildenafil increases splanchnic blood flow and changes the hepatic venous pressure gradient (HVPG) in patients with cirrhosis. Phosphodiesterase type-5 inhibitors are valuable in the treatment of erectile dysfunction and pulmonary hypertension in patients with end-stage liv...... type-5 inhibitor sildenafil, the present study could not demonstrate any clinical relevant influence on splanichnic blood flow, oxygen consumption or the HVPG....

  17. Theobromine up-regulates cerebral brain-derived neurotrophic factor and facilitates motor learning in mice

    OpenAIRE

    Yoneda, Mitsugu; Sugimoto, Naotoshi; Katakura, Masanori; Matsuzaki, Kentaro; Tanigami, Hayate; Yachie, Akihiro; Ohno-Shosaku, Takako; Shido, Osamu

    2017-01-01

    Theobromine, which is a caffeine derivative, is the primary methylxanthine produced by Theobroma cacao. Theobromine works as a phosphodiesterase (PDE) inhibitor to increase intracellular cyclic adenosine monophosphate (cAMP). cAMP activates the cAMP-response element-binding protein (CREB), which is involved in a large variety of brain processes, including the induction of the brain-derived neurotrophic factor (BDNF). BDNF supports cell survival and neuronal functions, including learning and m...

  18. Pharmacological Prevention and Reversion of Erectile Dysfunction after Radical Prostatectomy, By Modulation of Nitric Oxide/Cgmp Pathways

    Science.gov (United States)

    2008-03-01

    and intensified CVOD (10); d) iNOS knock out mice had an increased collagen deposition in the penile corpora cavernosa with aging (35), and adult ...Xi L, Kukreja RC. Phosphodiesterase-5 inhibitor sildenafil preconditions adult cardiac myocytes against necrosis and apoptosis. Essential role of...in hypothyroidism . Am J Physiol Endocrinol Metab. 2007 292(1):E175-86 33. Ferrini MG, Kovanecz I, Sanchez S, Vernet D, Davila HH, Rajfer J,Gonzalez

  19. Desynchronization of cells on the developmental path triggers the formation of spiral waves of cAMP during Dictyostelium aggregation

    OpenAIRE

    Lauzeral, Jacques; Halloy, José; Goldbeter, Albert

    1997-01-01

    Whereas it is relatively easy to account for the formation of concentric (target) waves of cAMP in the course of Dictyostelium discoideum aggregation after starvation, the origin of spiral waves remains obscure. We investigate a physiologically plausible mechanism for the spontaneous formation of spiral waves of cAMP in D. discoideum. The scenario relies on the developmental path associated with the continuous changes in the activity of enzymes such as adenylate cyclase and phosphodiesterase ...

  20. Treatment of infertility in men with spinal cord injury

    DEFF Research Database (Denmark)

    Brackett, N.L.; Lynne, C.M.; El Dib, Hussein Ibrahim El Desouki Hussein

    2010-01-01

    Most men with spinal cord injury (SCI) are infertile. Erectile dysfunction, ejaculatory dysfunction and semen abnormalities contribute to the problem. Treatments for erectile dysfunction include phosphodiesterase type 5 inhibitors, intracavernous injections of alprostadil, penile prostheses...... of intrauterine insemination increases as the total motile sperm count inseminated increases. In vitro fertilization and intracytoplasmic sperm injection are options in cases of extremely low total motile sperm count. Reproductive outcomes for SCI male factor infertility are similar to outcomes for general male...... factor infertility...

  1. Analysis of pyrimidine dimer content of isolated DNA by nuclease digestion

    International Nuclear Information System (INIS)

    Farland, W.H.; Sutherland, B.M.

    1980-01-01

    Isolated DNA is highly susceptible to degradation by exogenous nucleases. Complete digestion is possible with a number of well-characterized enzymes from a variety of sources. Treatment of DNA with a battery of enzymes including both phosphodiesterase and phosphatase activities yields a mixture of nucleosides and inorganic phosphate (P/sub i/) as a final product. Unlike native DNA, ultraviolet-irradiated DNA is resistant to complete digestion. Setlow et al. demonstrated that the structural changes in the DNA responsible for the nuclease resistance were the formation of cyclobutyl pyrimidine dimers, the major photoproduct in UV-irradiated DNA. Using venom phosphodiesterase, they demonstrated that UV irradiation of DNA affected both the rate and extent of enzymatic hydrolysis. In addition, it was demonstrated that the major nuclease-resistant product of this hydrolysis was an oligonucleotide containing dimerized pyrimidines. Treatment of the DNA to split the dimers, either photochemically or photoenzymatically, rendered the polymer more susceptible to hydrolysis by the phosphodiesterase. The specificity of photoreactivating enzyme for pyrimidine dimers lends support to the role of these structures in conferring nuclease resistance to UV-irradiated DNA. The nuclease resistance of DNA containing dimers has been the basis of several assays for the measurement of these photoproducts. Sutherland and Chamberlin reported the development of a rapid and sensitive assay for dimers in 32 P-labeled DNA

  2. Specific binding of (/sup 3/H)LY186126, an analogue of indolidan (LY195115), to cardiac membranes enriched in sarcoplasmic reticulum vesicles

    Energy Technology Data Exchange (ETDEWEB)

    Kauffman, R.F.; Utterback, B.G.; Robertson, D.W.

    1989-05-01

    LY186126 was found to be a potent inhibitor of type IV cyclic AMP phosphodiesterase located in the sarcoplasmic reticulum of canine cardiac muscle. This compound, a close structural analogue of indolidan (LY195115), was prepared in high specific activity, tritiated form to study the positive inotropic receptor(s) for cardiotonic phosphodiesterase inhibitors such as indolidan and milrinone. A high-affinity binding site for (/sup 3/H)LY186126 was observed (Kd = 4 nM) in purified preparations of canine cardiac sarcoplasmic reticulum vesicles. Binding was proportional to vesicle protein, was inactivated by subjecting membranes to proteolysis or boiling, and was dependent on added Mg2+. Scatchard analysis suggested the presence of a single class of binding sites in the membrane preparation. Indolidan, milrinone, and LY186126 (all at 1 microM) produced essentially complete displacement of bound (/sup 3/H)LY186126, while nifedipine, propranolol, and prazosin had little or no effect at this concentration. This represents the first reported use of a radioactive analogue to label the inotropic receptor for cardiotonic phosphodiesterase inhibitors. The results suggest that (/sup 3/H)LY186126 is a useful radioligand for examining the subcellular site(s) responsible for positive inotropic effects of these drugs.

  3. Specific binding of [3H]LY186126, an analogue of indolidan (LY195115), to cardiac membranes enriched in sarcoplasmic reticulum vesicles

    International Nuclear Information System (INIS)

    Kauffman, R.F.; Utterback, B.G.; Robertson, D.W.

    1989-01-01

    LY186126 was found to be a potent inhibitor of type IV cyclic AMP phosphodiesterase located in the sarcoplasmic reticulum of canine cardiac muscle. This compound, a close structural analogue of indolidan (LY195115), was prepared in high specific activity, tritiated form to study the positive inotropic receptor(s) for cardiotonic phosphodiesterase inhibitors such as indolidan and milrinone. A high-affinity binding site for [ 3 H]LY186126 was observed (Kd = 4 nM) in purified preparations of canine cardiac sarcoplasmic reticulum vesicles. Binding was proportional to vesicle protein, was inactivated by subjecting membranes to proteolysis or boiling, and was dependent on added Mg2+. Scatchard analysis suggested the presence of a single class of binding sites in the membrane preparation. Indolidan, milrinone, and LY186126 (all at 1 microM) produced essentially complete displacement of bound [ 3 H]LY186126, while nifedipine, propranolol, and prazosin had little or no effect at this concentration. This represents the first reported use of a radioactive analogue to label the inotropic receptor for cardiotonic phosphodiesterase inhibitors. The results suggest that [ 3 H]LY186126 is a useful radioligand for examining the subcellular site(s) responsible for positive inotropic effects of these drugs

  4. Sildenafil citrate-restored eNOS and PDE5 regulation in sickle cell mouse penis prevents priapism via control of oxidative/nitrosative stress.

    Science.gov (United States)

    Bivalacqua, Trinity J; Musicki, Biljana; Hsu, Lewis L; Berkowitz, Dan E; Champion, Hunter C; Burnett, Arthur L

    2013-01-01

    Sildenafil citrate revolutionized the practice of sexual medicine upon its federal regulatory agency approval approximately 15 years ago as the prototypical phosphodiesterase type 5 inhibitor indicated for the treatment of male erectile dysfunction. We now provide scientific support for its alternative use in the management of priapism, a clinical disorder of prolonged and uncontrolled penile erection. Sildenafil administered continuously to sickle cell mice, which show a priapism phenotype, reverses oxidative/nitrosative stress effects in the penis, mainly via reversion of uncoupled endothelial nitric oxide synthase to the functional coupled state of the enzyme, which in turn corrects aberrant signaling and function of the nitric oxide/cyclic GMP/protein kinase G/phosphodiesterase type 5 cascade. Priapism tendencies in these mice are reverted partially toward normal neurostimulated erection frequencies and durations after sildenafil treatment in association with normalized cyclic GMP concentration, protein kinase G activity and phosphodiesterase type 5 activity in the penis. Thus, sildenafil exerts pleiotropic effects in the penis that extend to diverse erection disorders.

  5. Influence of metabolism modifiers of cyclic nucleotides on contractility of right ventricle of rat heart with intact and removed endocardial endothelium

    Directory of Open Access Journals (Sweden)

    Savić Slađana

    2010-01-01

    Full Text Available Introduction. Endocardial endothelium, a natural biological barrier between circulating blood in heart ventricle and cells, creates a complex yet finely tuned balance of interactions with the immediate environment. Objective. We investigated the roles of theophylline, nonspecific phosphodiesterase inhibitor, and imidazole, an activator of phosphodiesterase on contractility of the right ventricle of rat heart, with intact and removed endocardial endothelium. Methods. Adult rats, of both sexes, type Wistar albino, were used in this experiment. All experiments were conducted on the preparations of the right ventricle using two experimental models. In the first experimental model, an endocardial endothelium (EE was preserved, and in the second model, an endocardial endothelium (-EE was removed using 1% solution Triton X-100. Results. Theophylline (1x10-2 mol/l expressed the positive inotropic effect on the heart, regardless of the presence of the endocardial endothelium. Inotropic response as multiple process can be induced by inhibition of phosphodiesterase, accumulation of cyclic nucleotides and activation of Ca2+ channels. Imidazole (2x10-3 mol/l increased the contractility of the right ventricle of the heart with EE. The modulator effect of endocardial endothelium on contractility of imidazole proved to be significant. As imidazole influenced the contractility of the right ventricle only in the presence of the endocardial endothelium, it is assumed that its effect is mediated via deliverance of endothelial mediators with positive inotropic effect. Conclusion. An intact endocardial endothelium is necessary for completion of contractile performance of the heart.

  6. Structural similarities and functional differences clarify evolutionary relationships between tRNA healing enzymes and the myelin enzyme CNPase.

    Science.gov (United States)

    Muruganandam, Gopinath; Raasakka, Arne; Myllykoski, Matti; Kursula, Inari; Kursula, Petri

    2017-05-16

    Eukaryotic tRNA splicing is an essential process in the transformation of a primary tRNA transcript into a mature functional tRNA molecule. 5'-phosphate ligation involves two steps: a healing reaction catalyzed by polynucleotide kinase (PNK) in association with cyclic phosphodiesterase (CPDase), and a sealing reaction catalyzed by an RNA ligase. The enzymes that catalyze tRNA healing in yeast and higher eukaryotes are homologous to the members of the 2H phosphoesterase superfamily, in particular to the vertebrate myelin enzyme 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase). We employed different biophysical and biochemical methods to elucidate the overall structural and functional features of the tRNA healing enzymes yeast Trl1 PNK/CPDase and lancelet PNK/CPDase and compared them with vertebrate CNPase. The yeast and the lancelet enzymes have cyclic phosphodiesterase and polynucleotide kinase activity, while vertebrate CNPase lacks PNK activity. In addition, we also show that the healing enzymes are structurally similar to the vertebrate CNPase by applying synchrotron radiation circular dichroism spectroscopy and small-angle X-ray scattering. We provide a structural analysis of the tRNA healing enzyme PNK and CPDase domains together. Our results support evolution of vertebrate CNPase from tRNA healing enzymes with a loss of function at its N-terminal PNK-like domain.

  7. Urban waste compost: Effects on physical, chemical, and biochemical soil properties

    Energy Technology Data Exchange (ETDEWEB)

    Giusquiani, P.L.; Gigliotti, G.; Businelli, D. [Istituto di Chimica Agraria dell`Universita, Perugia (Italy)] [and others

    1995-01-01

    A long-term field experiment was conducted to determine the effect of the additions of urban waste compost on the physical and chemical properties and enzymatic activities in a calcareous soil (Fluventic Xerochrept). Total Porosity (pores >50 pm measured on thin soil sections from undisturbed samples by image analysis) was greater in the plots treated with compost than the control plots due to a larger amount of elongated pores. In the amended plots total and humified organic C, Pb, Cu, and Zn showed a significant increase compared with nonamended plots. Enzymatic activities (L-asparaginase, arylsulphatase, dehydrogenase, phosphodiesterase, and alkaline phosphomonoesterase) were significantly enhanced by the compost addition thus indicating no inhibiting influence of the heavy metals present. The increased levels of the arylsulphatase, dehydrogenase, phosphodiesterase, and phosphomonoesterase activities were significantly correlated with total porosity: the first three with pores ranging from 50 to 1000 {mu}m, mainly with pores 50 to 200 {mu}m in size and phosphomonoesterase only with pores whose size was <500 {mu}m. L-asparaginase activity was not correlated with porosity. Only arylsulphatase, dehydrogenase, and phosphodiesterase were negatively correlated with bulk density. 44 refs., 4 figs., 6 tabs.

  8. Sildenafil citrate-restored eNOS and PDE5 regulation in sickle cell mouse penis prevents priapism via control of oxidative/nitrosative stress.

    Directory of Open Access Journals (Sweden)

    Trinity J Bivalacqua

    Full Text Available Sildenafil citrate revolutionized the practice of sexual medicine upon its federal regulatory agency approval approximately 15 years ago as the prototypical phosphodiesterase type 5 inhibitor indicated for the treatment of male erectile dysfunction. We now provide scientific support for its alternative use in the management of priapism, a clinical disorder of prolonged and uncontrolled penile erection. Sildenafil administered continuously to sickle cell mice, which show a priapism phenotype, reverses oxidative/nitrosative stress effects in the penis, mainly via reversion of uncoupled endothelial nitric oxide synthase to the functional coupled state of the enzyme, which in turn corrects aberrant signaling and function of the nitric oxide/cyclic GMP/protein kinase G/phosphodiesterase type 5 cascade. Priapism tendencies in these mice are reverted partially toward normal neurostimulated erection frequencies and durations after sildenafil treatment in association with normalized cyclic GMP concentration, protein kinase G activity and phosphodiesterase type 5 activity in the penis. Thus, sildenafil exerts pleiotropic effects in the penis that extend to diverse erection disorders.

  9. Impact of aging and comorbidity on the efficacy of low-intensity shock wave therapy for erectile dysfunction.

    Science.gov (United States)

    Hisasue, Shin-ichi; China, Toshiyuki; Horiuchi, Akira; Kimura, Masaki; Saito, Keisuke; Isotani, Shuji; Ide, Hisamitsu; Muto, Satoru; Yamaguchi, Raizo; Horie, Shigeo

    2016-01-01

    To evaluate the efficacy of low-intensity shock wave therapy and to identify the predictive factors of its efficacy in Japanese patients with erectile dysfunction. The present study included 57 patients with erectile dysfunction who satisfied all the following conditions: more than 6-months history of erectile dysfunction, sexual health inventory for men score of ≤ 12 without phosphodiesterase type-5 inhibitor, erection hardness score grade 1 or 2, mean penile circumferential change by erectometer assessing sleep related erection of energy shock waves generator (ED1000; Medispec, Gaithersburg, MD, USA). A total of 12 shock wave treatments were applied. Sexual health inventory for men score, erection hardness score with or without phosphodiesterase type-5 inhibitor, and mean penile circumferential change were assessed at baseline, 1, 3 and 6 months after the termination of low-intensity shock wave therapy. Of 57 patients who were assigned for the low-intensity shock wave therapy trial, 56 patients were analyzed. Patients had a median age of 64 years. The sexual health inventory for men and erection hardness score (with and without phosphodiesterase type-5 inhibitor) were significantly increased (P wave therapy (P wave therapy seems to be an effective physical therapy for erectile dysfunction. Age and comorbidities are negative predictive factors of therapeutic response. © 2015 The Japanese Urological Association.

  10. Avanafil for erectile dysfunction in elderly and younger adults: differential pharmacology and clinical utility

    Directory of Open Access Journals (Sweden)

    Katz EG

    2014-08-01

    Full Text Available Eric G Katz,1 Ronny BW Tan,2 Daniel Rittenberg,1 Wayne J Hellstrom3 1Tulane University School of Medicine, New Orleans, LA, USA; 2Department of Urology, Tan Tock Seng Hospital, Singapore; 3Section of Andrology, Department of Urology, Tulane University School of Medicine, New Orleans, LA, USA Abstract: The treatment modalities of erectile dysfunction range from oral pharmacotherapy to intracavernosal injections, intraurethral pellets, vacuum erectile devices, and the surgical option of penile prosthesis insertion. Oral phosphodiesterase 5 inhibitors still remain the preferred treatment for patients since they are the least invasive, not to mention that they can be prescribed by non-urologists. Due to these factors, there has been development of newer drugs with fewer side effects. This is a review of the second generation phosphodiesterase 5 inhibitor, avanafil, looking into its pharmacology as well as its clinical utility. Avanafil's faster onset and shorter duration of action has made it preferred as compared to other PDE5 inhibitors for patients with multiple comorbidities. Keywords: phosphodiesterase 5 inhibitors, impotence, sildenafil, sexual dysfunction, nitric oxide

  11. Sexual function in hypertensive patients receiving treatment

    Directory of Open Access Journals (Sweden)

    Thorsten Reffelmann

    2006-12-01

    Full Text Available Thorsten Reffelmann, Robert A KlonerUniversity of Southern California, The Heart Institute, Good Samaritan Hospital, Division of Cardiovascular Medicine, Keck School of Medicine, Los Angeles, CA, USAAbstract: In many forms of erectile dysfunction (ED, cardiovascular risk factors, in particular arterial hypertension, seem to be extremely common. While causes for ED are related to a broad spectrum of diseases, a generalized vascular process seems to be the underlying mechanism in many patients, which in a large portion of clinical cases involves endothelial dysfunction, ie, inadequate vasodilation in response to endothelium-dependent stimuli, both in the systemic vasculature and the penile arteries. Due to this close association of cardiovascular disease and ED, patients with ED should be evaluated as to whether they may suffer from cardiovascular risk factors including hypertension, cardiovascular disease or silent myocardial ischemia. On the other hand, cardiovascular patients, seeking treatment of ED, must be evaluated in order to decide whether treatment of ED or sexual activity can be recommended without significantly increased cardiac risk. The guideline from the first and second Princeton Consensus Conference may be applied in this context. While consequent treatment of cardiovascular risk factors should be accomplished in these patients, many antihypertensive drugs may worsen sexual function as a drug specific side-effect. Importantly, effective treatment for arterial hypertension should not be discontinued as hypertension itself may contribute to altered sexual functioning; to the contrary, alternative antihypertensive regimes should be administered with individually tailored drug regimes with minimal side-effects on sexual function. When phosphodiesterase-5 inhibitors, such as sildenafil, tadalafil and vardenafil, are prescribed to hypertensive patients on antihypertensive drugs, these combinations of antihypertensive drugs and

  12. Milrinone enhances relaxation to prostacyclin and iloprost in pulmonary arteries isolated from lambs with persistent pulmonary hypertension of the newborn

    Science.gov (United States)

    Lakshminrusimha, Satyan; Porta, Nicolas F. M.; Farrow, Kathryn N.; Chen, Bernadette; Gugino, Sylvia F.; Kumar, Vasanth H.; Russell, James A.; Steinhorn, Robin H.

    2009-01-01

    Prostacyclin is a pulmonary vasodilator and is produced by prostacyclin synthase and stimulates adenylate cyclase (AC) via the prostacyclin receptor (IP) to produce cAMP. Forskolin is a direct stimulant of AC. Phosphodiesterase 3 hydrolyzes cAMP and is inhibited by milrinone. Objective To characterize the prostacyclin-AC-cAMP pathway in the ovine ductal ligation model of persistent pulmonary hypertension of the newborn (PPHN). Setting University-based laboratory animal facility. Subjects Lambs delivered to time-dated pregnant ewes. Interventions Fifth generation pulmonary arteries (PA) and lung parenchyma were isolated from control fetal lambs (n = 8) and fetal lambs with PPHN induced by antenatal ductal ligation (n = 9). We studied relaxation responses to various agonists (milrinone, forskolin, prostacyclin, and iloprost, a prostacyclin analog) that increase cAMP in PA after half-maximal constriction with norepinephrine and pretreatment with propranolol ± indo-methacin. Lung protein levels of prostacyclin synthase, IP, AC2, and phosphodiesterase 3A were analyzed by Western blot and cAMP by enzyme-linked immunoassay. Main Results Milrinone relaxed control and PPHN PA and pretreatment with indomethacin significantly impaired this response. Relaxation to milrinone, prostacyclin, and iloprost were significantly impaired in PA from PPHN lambs. Pretreatment with milrinone markedly enhanced relaxation to prostacyclin and iloprost in PPHN PA, similar to relaxation in control PA. Relaxation to forskolin was similar in control and PPHN PAs indicating normal AC activity. Protein levels of prostacyclin synthase and IP were decreased in PPHN lungs compared with control, but AC2, cAMP, and phosphodiesterase 3A remained unchanged. Conclusions Prostacyclin and iloprost are dilators of PAs from PPHN lambs and their effect is enhanced by milrinone. This combination therapy may be an effective strategy in the management of patients with PPHN. PMID:19057444

  13. Effect of Exogenous Phytase Addition on Soil Phosphatase Activities: a Fluorescence Spectroscopy Study.

    Science.gov (United States)

    Yang, Xiao-zhu; Chen, Zhen-hua; Zhang, Yu-lan; Chen, Li-jun

    2015-05-01

    The utilization of organic phosphorus (P) has directly or indirectly improved after exogenous phytase was added to soil. However, the mechanism by which exogenous phytase affected the soil phosphatases (phosphomonoesterase and phosphodiesterase) activities was not clear. The present work was aimed to study red soil, brown soil and cinnamon soil phosphomonoesterase (acid and alkaline) (AcP and AlP) and phosphodiesterase (PD) activities responding to the addition of exogenous phytase (1 g phytase/50 g air dry soil sample) based on the measurements performed via a fluorescence detection method combined with 96 microplates using a TECAN Infinite 200 Multi-Mode Microplate Reader. The results indicated that the acid phosphomonoesterase activity was significantly enhanced in red soil (p≤0. 01), while it was significantly reduced in cinnamon soil; alkaline phosphomonoesterase activity was significantly enhanced in cinnamon soil (p≤ 0. 01), while it was significantly reduced in red soil; phosphodiesterase activity was increased in three soils but it was significantly increased in brown soil (p≤0. 01) after the addition of exogenous phytase. The activities still remained strong after eight days in different soils, which indicated that exogenous phytase addition could be enhance soil phosphatases activities effectively. This effect was not only related to soil properties, such as pH and phosphorus forms, but might also be related to the excreted enzyme amount of the stimulating microorganism. Using fluorescence spectroscopy to study exogenous phytase addition influence on soil phosphatase activities was the first time at home and abroad. Compared with the conventional spectrophotometric method, the fluorescence microplate method is an accurate, fast and simple to use method to determine the relationships among the soil phosphatases activities.

  14. An unusual diphosphatase from the PhnP family cleaves reactive FAD photoproducts.

    Science.gov (United States)

    Beaudoin, Guillaume A W; Li, Qiang; Bruner, Steven D; Hanson, Andrew D

    2018-01-11

    Flavins are notoriously photolabile, but while the photoproducts derived from the iso -alloxazine ring are well known the other photoproducts are not. In the case of FAD, typically the main cellular flavin, the other photoproducts are predicted to include four- and five-carbon sugars linked to ADP. These FAD photoproducts were shown to be potent glycating agents, more so than ADP-ribose. Such toxic compounds would require disposal via an ADP-sugar diphosphatase or other route. Comparative analysis of bacterial genomes uncovered a candidate disposal gene that is chromosomally clustered with genes for FAD synthesis or transport and is predicted to encode a protein of the PhnP cyclic phosphodiesterase family. The representative PhnP family enzyme from Koribacter versatilis (here named Fpd, F AD p hotoproduct d iphosphatase) was found to have high, Mn 2+ -dependent diphosphatase activity against FAD photoproducts, FAD, and ADP-ribose, but almost no phosphodiesterase activity against riboflavin 4',5'-cyclic phosphate, a chemical breakdown product of FAD. To provide a structural basis of the unique Fpd activity, the crystal structure of K. versatilis Fpd was determined. The results place Fpd in the broad metallo-β-lactamase-like family of hydrolases, a diverse family commonly using two metals for hydrolytic catalysis. The active site of Fpd contains two Mn 2+ ions and a bound phosphate, consistent with a diphosphatase mechanism. Our results characterize the first PhnP family member that is a diphosphatase rather than a cyclic phosphodiesterase and suggest its involvement in a cellular damage-control system that efficiently hydrolyzes the reactive, ADP-ribose-like products of FAD photodegradation. © 2018 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  15. Chemoprevention of Breast Cancer by Mimicking the Protective Effect of Early First Birth. Addendum

    Science.gov (United States)

    2013-03-01

    Ig lambda-1 chain C region 363828 Immunoglobulin Immune 1.5 1.4 1.4 1.3 1.4 Malic enzyme 1 Me1 24552 Pyruvate synthesis Metabolism 1.3 1.4 1.4 1.1...1.3 biosynthesis Differentation Malic enzyme 1 Me1 24552 Pyruvate synthesis Metabolism 1.3 1.4 1.4 1.1 1.3 Phosphodiesterase 4B Pde4b 24626 cAMP...Contraception 86 (2012) 238–243dense breast tissue in the upper-outer quadrant of the breast. After anesthetizing the breast with 1% lidocaine , a 4-mm

  16. Roflumilast Usage from 2010 to 2016

    DEFF Research Database (Denmark)

    Salvesen, Øyvind Nicolay Ulland; Davidsen, Jesper Rømhild; Pottegård, Anton

    2018-01-01

    Roflumilast, a phosphodiesterase-4-inhibitor, is marketed as add-on treatment to inhaled bronchodilators and corticosteroids in COPD patients with frequent exacerbations. Although marketed since 2010, usage pattern of roflumilast for an entire nation has not previously been explored. This study...... (OR 0.62; 95% CI 0.49-0.80). The decreasing incidence and high level of early roflumilast discontinuation could be due to lack of benefit, a low awareness of romiflulast's indication among physicians, secondary to a challenging prescribing procedure, or to adverse effects. This article is protected...

  17. Low-intensity shockwave therapy for erectile dysfunction

    DEFF Research Database (Denmark)

    Fode, Mikkel; Hatzichristodoulou, Georgios; Serefoglu, Ege Can

    2017-01-01

    Erectile dysfunction (ED) affects ∼30% of all men above the age of 40 years and its prevalence steadily increases with age. Current nonsurgical treatment options, including phosphodiesterase type 5 inhibitors (PDE5I), provide temporary relief but have failed to provide a permanent improvement...... treatment for ED that might offer a cure, which is the most desired outcome for most men with ED. Li-ESWT has also been suggested to improve the effect of PDE5I in nonresponders, reducing the need for more invasive treatments. Several single-arm trials have shown benefit of Li-ESWT on patient...

  18. Continuous Intravenous Milrinone Therapy in Pediatric Outpatients.

    Science.gov (United States)

    Curley, Michelle; Liebers, Jill; Maynard, Roy

    Milrinone is a phosphodiesterase 3 inhibitor with both positive inotropic and vasodilator properties. Administered as a continuous infusion, milrinone is indicated for the short-term treatment of patients with acute decompensated heart failure. Despite limited data supporting long-term milrinone therapy in adults with congestive heart failure, children managed as outpatients may benefit from continuous milrinone as a treatment for cardiac dysfunction, as a destination therapy for cardiac transplant, or as palliative therapy for cardiomyopathy. The aim of this article is to review the medical literature and describe a home infusion company's experience with pediatric outpatient milrinone therapy.

  19. Enantiodivergent Synthesis of (R- and (S-Rolipram

    Directory of Open Access Journals (Sweden)

    Esteban Pombo-Villar

    1998-03-01

    Full Text Available Both enantiomers of rolipram (1 have been prepared in large quantity from a common intermediate rac-3-(3’-cyclopentyloxy-4’-methoxyphenyl-4-nitro butyric acid (6, which was resolved by way of the two readily separable diastereoisomeric amides obtained with (S-(--phenylethylamine. Reduction of the nitro group and intramolecular transamidation gave (R-(--1 and (S-(+-1, respectively. CD spectra of both enantiomers of rolipram are reported and discussed. Both enantiomers of rolipram presented the same potency of inhibitory activity against recombinant cyclic-AMP-selective phosphodiesterase (PDE4 subtypes.

  20. Functions of PDE3 Isoforms in Cardiac Muscle

    Science.gov (United States)

    Movsesian, Matthew; Ahmad, Faiyaz

    2018-01-01

    Isoforms in the PDE3 family of cyclic nucleotide phosphodiesterases have important roles in cyclic nucleotide-mediated signalling in cardiac myocytes. These enzymes are targeted by inhibitors used to increase contractility in patients with heart failure, with a combination of beneficial and adverse effects on clinical outcomes. This review covers relevant aspects of the molecular biology of the isoforms that have been identified in cardiac myocytes; the roles of these enzymes in modulating cAMP-mediated signalling and the processes mediated thereby; and the potential for targeting these enzymes to improve the profile of clinical responses. PMID:29415428

  1. Product-related research: how research can contribute to successful life-cycle management.

    Science.gov (United States)

    Sandner, Peter; Ziegelbauer, Karl

    2008-05-01

    Declining productivity with decreasing new molecular entity output combined with increased R&D spending is one of the key challenges for the entire pharmaceutical industry. In order to offset decreasing new molecular entity output, life-cycle management activities for established drugs become more and more important to maintain or even expand clinical indication and market opportunities. Life-cycle management covers a whole range of activities from strategic pricing to a next generation product launch. In this communication, we review how research organizations can contribute to successful life-cycle management strategies using phosphodiesterase 5 inhibitors as an example.

  2. Endovascular treatment of vasculogenic erectile dysfunction

    OpenAIRE

    O. B. Zhukov; S. N. Shcherbinin; V. A. Ukolov

    2014-01-01

    Method of choice for surgical treatment of vasculogenic erectile dysfunction (ED) is the genesis of arteriovenous falloprosthetics. In the initial stages of the disease, young men, dissatisfied inhibitor therapy 5-phosphodiesterase and/or intracavernous injections do not agree to such a view of his proposed lecheniya. Authors give the results we operated 26 patients 25–48 year old (mean age 34.3± 7.4) with vasculogenic ED. Of these, 23 patients with venoocclusive ED, 3 patients had arterial i...

  3. Tadalafil reversal of sexual dysfunction caused by serotonin enhancing medications in women.

    Science.gov (United States)

    Ashton, Adam Keller; Weinstein, Wendy

    2006-01-01

    Sexual dysfunction is a common side effect of many antidepressants, especially those that increase serotonin. Many strategies have been reported to assist patients in minimizing impairment, with variable degrees of success. One of the newer approaches is to augment with phosphodiesterase type-5 inhibitors. Our report using the most recently released agent in this class, tadalafil is the first demonstrating potential benefit in women. We report here of three women who derived benefit from using 20 mg of tadalafil before anticipated sexual activity to reverse medication-induced sexual dysfunction. Tadalafil utility was maintained over time and was well tolerated.

  4. Pharmacologic Therapy in Men's Health: Hypogonadism, Erectile Dysfunction, and Benign Prostatic Hyperplasia.

    Science.gov (United States)

    Berkseth, Kathryn E; Thirumalai, Arthi; Amory, John K

    2016-07-01

    This article reviews current pharmacologic treatment options for 3 common men's health concerns: hypogonadism, erectile dysfunction (ED), and benign prostatic hyperplasia (BPH). Specific topics addressed include: management of male hypogonadism using testosterone replacement therapy, use of oral phosphodiesterase inhibitors as first-line therapy for men with ED and the utility of intraurethral and intrapenile alprostadil injections for patients who do not respond to oral medications, and the role of alpha1-adrenergic antagonists, 5-alpha-reductase inhibitors, anticholinergic agents, and herbal therapies in the management of BPH. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. In vitro and in vivo generation and characterization of Pseudomonas aeruginosa biofilm-dispersed cells via c-di-GMP manipulation

    DEFF Research Database (Denmark)

    Chua, Song Lin; Hultqvist, Louise D; Yuan, Mingjun

    2015-01-01

    Bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) is a global secondary bacterial messenger that controls the formation of drug-resistant multicellular biofilms. Lowering the intracellular c-di-GMP content can disperse biofilms, and it is proposed as a biofilm eradication strategy...... biofilms by reducing the intracellular c-di-GMP content through modulation of phosphodiesterases (PDEs). Unlike conventional protocols that demonstrate biofilm dispersal by biomass quantification, our protocols enable physiological characterization of the dispersed cells. Biomarkers of dispersed cells...

  6. Cerebral haemodynamic response or excitability is not affected by sildenafil

    DEFF Research Database (Denmark)

    Kruuse, Christina; Hansen, Adam E; Larsson, Henrik B W

    2009-01-01

    Sildenafil (Viagra), a cyclic guanosine monophosphate-degrading phosphodiesterase 5 inhibitor, induces headache and migraine. Such headache induction may be caused by an increased neuronal excitability, as no concurrent effect on cerebral arteries is found. In 13 healthy females (23+/-3 years, 70...... amplitude or latency (P100). The fMRI response to visual stimulation or hypercapnia was unchanged by sildenafil. In conclusion, sildenafil induces mild headache without potentiating a neuronal or local cerebrovascular visual response or a global cerebrovascular hypercapnic response. The implication...

  7. Effect of sildenafil on gastric emptying and postprandial frequency of antral contractions in healthy humans

    DEFF Research Database (Denmark)

    Madsen, Jan Lysgård; Søndergaard, S B; Fuglsang, Stefan

    2004-01-01

    BACKGROUND: Sildenafil is known to block phosphodiesterase type 5, which degrades nitric oxide-stimulated cyclic guanosine monophosphate, thereby relaxing smooth muscle cells in various organs. The effect of sildenafil on gastric motor function after a meal was investigated in healthy humans...... gastric emptying and postprandial frequency of antral contractions. RESULTS: The area under the curve of gastric retention versus time of liquid or solid radiolabelled marker was not changed by sildenafil intake, nor was the postprandial frequency of antral contractions affected by sildenafil. CONCLUSION......: A single dose of 50 mg sildenafil does not change gastric emptying or postprandial frequency of antral contractions in healthy volunteers....

  8. Investigation of in vitro and in vivo anti-asthmatic properties of Siphonochilus aethiopicus

    CSIR Research Space (South Africa)

    Fouché, Gerda

    2011-01-01

    Full Text Available -induced bronchoconstriction and eosinophil infiltration in the guinea pig by the cyclic AMP-specific phosphodiesterase inhibitor, rolipram. Journal of Pharmacology and Experimental Therapeutics. 266, 306-13. Van Wyk, B., Van Oudtshoorn, B., Gericke, N., 2009. Medicinal... in the production of prostaglandins that was later confirmed by J?ger and Van Staden (2005) reporting an inhibitory effect of extracts from this plant on COX-1 activity. 5 Extracts from S. aethiopicus have also been associated with anti-infective activity...

  9. Extracorporeal shock wave therapy (ESWT) in urology

    DEFF Research Database (Denmark)

    Fojecki, Grzegorz Lukasz; Thiessen, Stefan; Osther, Palle Jörn Sloth

    2017-01-01

    PURPOSE: The objective was to evaluate high-level evidence studies of extracorporeal shock wave therapy (ESWT) for urological disorders. METHODS: We included randomized controlled trials reporting outcomes of ESWT in urology. Literature search on trials published in English using EMBASE, Medline...... deviation and plaque size were observed. Four studies on erectile dysfunction (ED) including 337 participants were included. Using International Index of Erectile Function (IIEF-EF) and erectile hardness scale (EHS) data suggested a significant positive effect of ESWT in phosphodiesterase-5 inhibitor (PDE-5...

  10. Novel anti-inflammatory agents in COPD

    DEFF Research Database (Denmark)

    Loukides, Stelios; Bartziokas, Konstantinos; Vestbo, Jørgen

    2013-01-01

    Inflammation plays a central role in chronic obstructive pulmonary disease (COPD). COPD related inflammation is less responsive to inhaled steroids compared to asthma. There are three major novel anti-inflammatory approaches to the management of COPD. The first approach is phosphodiesterase...... on these strategies exist at the moment. A third potential approach involves novel agents whose mechanism of action is closely related to COPD mechanisms and pathophysiology. Such novel treatments are of great interest since they may treat both COPD and co-morbidities. Several novel agents are currently under...

  11. Six New Tetraprenylated Alkaloids from the South China Sea Gorgonian Echinogorgia pseudossapo

    Directory of Open Access Journals (Sweden)

    Zhang-Hua Sun

    2014-01-01

    Full Text Available Six new tetraprenylated alkaloids, designated as malonganenones L–Q (1–6, were isolated from the gorgonian Echinogorgia pseudossapo, collected in Daya Bay of Guangdong Province, China. The structures of 1–6 featuring a methyl group at N-3 and a tetraprenyl chain at N-7 in the hypoxanthine core were established by extensive spectroscopic analyses. Compounds 1–6 were tested for their inhibitory activity against the phosphodiesterases (PDEs-4D, 5A, and 9A, and compounds 1 and 6 exhibited moderate inhibitory activity against PDE4D with IC50 values of 8.5 and 20.3 µM, respectively.

  12. Caffeine, cyclic AMP and postreplication repair of mammalian DNA

    International Nuclear Information System (INIS)

    Ehmann, U.K.

    1976-01-01

    The methylxanthines, caffeine and theophylline, inhibit postreplication repair of DNA in mammalian cells. Because they also inhibit cyclic AMP phosphodiesterase, it was thought that there might be some connection between concentrations of cyclic AMP and postreplication repair. This possibility was tested by performing DNA sedimentation experiments with a cyclic AMP-resistant mouse lymphoma cell mutant and its wild-type counterpart. The results show that there is no connection between cellular cyclic AMP concentrations and the rate of postreplication repair. Therefore, it is more likely that caffeine and theophylline inhibit postreplication repair by some other means, such as by binding to DNA

  13. A multifaceted approach to maximize erectile function and vascular health.

    Science.gov (United States)

    Meldrum, David R; Gambone, Joseph C; Morris, Marge A; Ignarro, Louis J

    2010-12-01

    To review the role of various factors influencing vascular nitric oxide (NO) and cyclic GMP, and consequently, erectile function and vascular health. Pertinent publications are reviewed. Daily moderate exercise stimulates vascular NO production. Maintenance of normal body weight and waist/hip ratio allows NO stimulation by insulin. Decreased intake of fat, sugar, and simple carbohydrates rapidly converted to sugar reduces the adverse effects of fatty acids and sugar on endothelial NO production. Omega-3 fatty acids stimulate endothelial NO release. Antioxidants boost NO production and prevent NO breakdown. Folic acid, calcium, vitamin C, and vitamin E support the biochemical pathways leading to NO release. Cessation of smoking and avoidance of excessive alcohol preserve normal endothelial function. Moderate use of alcohol and certain proprietary supplements may favorably influence erectile and vascular function. Treatment of any remaining testosterone deficit will both increase erectile function and reduce any associated metabolic syndrome. After production of NO and cyclic GMP are improved, use of phosphodiesterase-5 inhibitors should result in greater success in treating remaining erectile dysfunction. Recent studies have also suggested positive effects of phosphodiesterase-5 inhibitors on vascular function. A multifaceted approach will maximize both erectile function and vascular health. Copyright © 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  14. PDE1C deficiency antagonizes pathological cardiac remodeling and dysfunction

    Science.gov (United States)

    Knight, Walter E.; Chen, Si; Zhang, Yishuai; Oikawa, Masayoshi; Wu, Meiping; Zhou, Qian; Miller, Clint L.; Cai, Yujun; Mickelsen, Deanne M.; Moravec, Christine; Small, Eric M.; Abe, Junichi; Yan, Chen

    2016-01-01

    Cyclic nucleotide phosphodiesterase 1C (PDE1C) represents a major phosphodiesterase activity in human myocardium, but its function in the heart remains unknown. Using genetic and pharmacological approaches, we studied the expression, regulation, function, and underlying mechanisms of PDE1C in the pathogenesis of cardiac remodeling and dysfunction. PDE1C expression is up-regulated in mouse and human failing hearts and is highly expressed in cardiac myocytes but not in fibroblasts. In adult mouse cardiac myocytes, PDE1C deficiency or inhibition attenuated myocyte death and apoptosis, which was largely dependent on cyclic AMP/PKA and PI3K/AKT signaling. PDE1C deficiency also attenuated cardiac myocyte hypertrophy in a PKA-dependent manner. Conditioned medium taken from PDE1C-deficient cardiac myocytes attenuated TGF-β–stimulated cardiac fibroblast activation through a mechanism involving the crosstalk between cardiac myocytes and fibroblasts. In vivo, cardiac remodeling and dysfunction induced by transverse aortic constriction, including myocardial hypertrophy, apoptosis, cardiac fibrosis, and loss of contractile function, were significantly attenuated in PDE1C-knockout mice relative to wild-type mice. These results indicate that PDE1C activation plays a causative role in pathological cardiac remodeling and dysfunction. Given the continued development of highly specific PDE1 inhibitors and the high expression level of PDE1C in the human heart, our findings could have considerable therapeutic significance. PMID:27791092

  15. DISC1, PDE4B, and NDE1 at the centrosome and synapse

    International Nuclear Information System (INIS)

    Bradshaw, Nicholas J.; Ogawa, Fumiaki; Antolin-Fontes, Beatriz; Chubb, Jennifer E.; Carlyle, Becky C.; Christie, Sheila; Claessens, Antoine; Porteous, David J.; Millar, J. Kirsty

    2008-01-01

    Disrupted-In-Schizophrenia 1 (DISC1) is a risk factor for schizophrenia and other major mental illnesses. Its protein binding partners include the Nuclear Distribution Factor E Homologs (NDE1 and NDEL1), LIS1, and phosphodiesterases 4B and 4D (PDE4B and PDE4D). We demonstrate that NDE1, NDEL1 and LIS1, together with their binding partner dynein, associate with DISC1, PDE4B and PDE4D within the cell, and provide evidence that this complex is present at the centrosome. LIS1 and NDEL1 have been previously suggested to be synaptic, and we now demonstrate localisation of DISC1, NDE1, and PDE4B at synapses in cultured neurons. NDE1 is phosphorylated by cAMP-dependant Protein Kinase A (PKA), whose activity is, in turn, regulated by the cAMP hydrolysis activity of phosphodiesterases, including PDE4. We propose that DISC1 acts as an assembly scaffold for all of these proteins and that the NDE1/NDEL1/LIS1/dynein complex is modulated by cAMP levels via PKA and PDE4.

  16. Enzymatic activity of granulations tissues under low doses of radiation. Biochemical analysis in rats

    International Nuclear Information System (INIS)

    Tosoni, Guilherme Monteiro; Boscolo, Frab Norberto; Cury, Jaime Aparecido; Watanabe, Plauto Christopher Aranha

    1994-01-01

    This paper was designed to investigate in the rat subcutaneous sponge-induced granulation tissue under low doses of X-ray, the activity of alkaline phosphatase, 5'nucleotide phosphodiesterase and adenosine triphosphatase (ATPase) enzymes. One hundred and fourteen Wistar rats were divided into three groups, as follows: Group I as control, Group II that received single 7,14 R in split-dosis immediately after sponge-implantation at the third and fifth days postoperatively. Biopsies were taken after 7, 11, 14, 21 and 28 days and the activity of the three enzymes was determined. The results have shown that in Group II alkaline phosphatase had higher activity in the 14th day of tissue evolution when compared to Groups I and III . The 5'nucleotide phosphodiesterase activity in Group I was similar in all days checked, although in Group II the enzyme showed higher activity in 7th day and lower in 21st. In Group III the activity was higher after 14 and 7 days and lower after 28 and 21 days. There was no observation of changing in adenosine triphosphatase (ATPase) activity when the three groups were compared. (author)

  17. Effects of Red Wine Vinegar Beverage on the Colonic Tissue of Rodents: Biochemical, Functional and Pharmacological Analyses.

    Science.gov (United States)

    Enkhsaikhan, Azjargal; Takahara, Akira; Nakamura, Yuji; Goto, Ai; Chiba, Koki; Lubna, Nur Jaharat; Hagiwara-Nagasawa, Mihoko; Izumi-Nakaseko, Hiroko; Ando, Kentaro; Naito, Atsuhiko T; Sugiyama, Atsushi

    2018-01-01

    A beverage made of red wine vinegar and grape juice (Yamanashi-no-megumi™) was developed as a supplemental fluid containing polyphenols, which has been clinically shown to enhance the colonic transit. In this study, we assessed the mechanism of its prokinetic action by analyzing the effects on both the colonic phosphodiesterase activity of rats (n=4) and the isolated colonic strip preparation of guinea pigs (n=4). The 7% (v/v) solution of the beverage significantly decreased the phosphodiesterase activity by 9% (n=4). The beverage in concentrations of 0.7, 2.1 and 7% (v/v) relaxed the colonic strips pre-contracted by 1 µmol/L of carbachol in a concentration-related manner with 50, 58 and 79%, each response of which was diminished to 11, 19 and 46%, respectively in the presence of 100 µmol/L of L-nitro-arginine methyl ester. These results obtained by biochemical, functional and pharmacological analyses suggest that the beverage could relax the colon through both cAMP-associated and nitric oxide-dependent pathways, which may partly explain clinically observed prokinetic effect of the beverage.

  18. Update on the clinical utility of sildenafil in the treatment of pulmonary arterial hypertension

    Directory of Open Access Journals (Sweden)

    Gautam V Ramani

    2010-05-01

    Full Text Available Gautam V Ramani, Myung H ParkUniversity of Maryland, Baltimore, MD, USAAbstract: Sildenafil is an orally administered phosphodiesterase type 5 inhibitor that is approved for the treatment of pulmonary arterial hypertension (PAH. The hemodynamic effects of sildenafil are mitigated primarily via potentiating the effects of endogenous nitric oxide, leading to smooth muscle cell relaxation and reductions in pulmonary arterial pressures and pulmonary vascular resistance. When added to standard background therapy in patients with idiopathic or associated PAH from congenital heart disease, anorexigen use, or connective tissue disease, sildenafil treatment results in improved exercise capacity as measured by 6 minute walk distance, improved hemodynamics, and favorable changes in quality of life. Sildenafil use is contraindicated with concomitant nitrate administration, and caution should be exercised when used in combination with antihypertensive agents due to risks of precipitating hypotension. Side effects are generally mild, and include flushing, headaches, and epistaxis. The combination of sildenafil with intravenous epoprostenol is safe and well tolerated, and further improves exercise capacity. Sildenafil is approved only for treatment of PAH, and although emerging data suggest a potential role in treating other types of pulmonary hypertension, larger trials are required to confirm these findings. Keywords: sildenafil, pulmonary arterial hypertension, phosphodiesterase type 5 inhibitor

  19. Identification of cancer cytotoxic modulators of PDE3A by predictive chemogenomics

    Science.gov (United States)

    de Waal, Luc; Lewis, Timothy A.; Rees, Matthew G.; Tsherniak, Aviad; Wu, Xiaoyun; Choi, Peter S.; Gechijian, Lara; Hartigan, Christina; Faloon, Patrick W.; Hickey, Mark J.; Tolliday, Nicola; Carr, Steven A.; Clemons, Paul A.; Munoz, Benito; Wagner, Bridget K.; Shamji, Alykhan F.; Koehler, Angela N.; Schenone, Monica; Burgin, Alex B.; Schreiber, Stuart L.; Greulich, Heidi; Meyerson, Matthew

    2015-01-01

    High cancer death rates indicate the need for new anti-cancer therapeutic agents. Approaches to discover new cancer drugs include target-based drug discovery and phenotypic screening. Here, we identified phosphodiesterase 3A modulators as cell-selective cancer cytotoxic compounds by phenotypic compound library screening and target deconvolution by predictive chemogenomics. We found that sensitivity to 6-(4-(diethylamino)-3-nitrophenyl)-5-methyl-4,5-dihydropyridazin-3(2H)-one, or DNMDP, across 766 cancer cell lines correlates with expression of the phosphodiesterase 3A gene, PDE3A. Like DNMDP, a subset of known PDE3A inhibitors kill selected cancer cells while others do not. Furthermore, PDE3A depletion leads to DNMDP resistance. We demonstrated that DNMDP binding to PDE3A promotes an interaction between PDE3A and Schlafen 12 (SLFN12), suggesting a neomorphic activity. Co-expression of SLFN12 with PDE3A correlates with DNMDP sensitivity, while depletion of SLFN12 results in decreased DNMDP sensitivity. Our results implicate PDE3A modulators as candidate cancer therapeutic agents and demonstrate the power of predictive chemogenomics in small-molecule discovery. PMID:26656089

  20. PDE5 Inhibitors-Loaded Nanovesicles: Physico-Chemical Properties and In Vitro Antiproliferative Activity

    Directory of Open Access Journals (Sweden)

    Roberta F. De Rose

    2016-05-01

    Full Text Available Novel therapeutic approaches are required for the less differentiated thyroid cancers which are non-responsive to the current treatment. In this study we tested an innovative formulation of nanoliposomes containing sildenafil citrate or tadalafil, phosphodiesterase-5 inhibitors, on two human thyroid cancer cell lines (TPC-1 and BCPAP. Nanoliposomes were prepared by the thin layer evaporation and extrusion methods, solubilizing the hydrophilic compound sildenafil citrate in the aqueous phase during the hydration step and dissolving the lipophilic tadalafil in the organic phase. Nanoliposomes, made up of 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine monohydrate (DPPC, cholesterol, and N-(carbonyl-methoxypolyethylene glycol-2000-1,2-distearoyl-sn-glycero-3-phosphoethanolamine (DSPE-mPEG2000 (6:3:1 molar ratio, were characterized by a mean diameter of ~100 nm, a very low polydispersity index (~0.1 and a negative surface charge. The drugs did not influence the physico-chemical properties of the systems and were efficiently retained in the colloidal structure. By using cell count and MTT assay, we found a significant reduction of the viability in both cell lines following 24 h treatment with both nanoliposomal-encapsulated drugs, notably greater than the effect of the free drugs. Our findings demonstrate that nanoliposomes increase the antiproliferative activity of phosphodiesterase-5 inhibitors, providing a useful novel formulation for the treatment of thyroid carcinoma.

  1. Non‑Hormonal treatment of BPH/BOO

    Directory of Open Access Journals (Sweden)

    Nadir I Osman

    2014-01-01

    Full Text Available Objectives: To review the use of non-hormonal pharmacotherapies in the treatment of lower urinary tract symptoms (LUTS due to presumed benign prostatic hyperplasia (BPH. Materials and Methods: A search of the PUBMED database was conducted for the terms BPH, LUTS, bladder outlet obstruction, alpha-adrenoceptor blockers, anti-muscarinics, and phosphodiesterase-5-inhibitors. Results: Medical therapy has long been established as the accepted standard of care in the treatment of male LUTS. The aim of treatment is improvement in symptoms and quality of life whilst minimizing adverse effects. The agents most widely used as 1 st line therapy are alpha-blockers (AB, as a standalone or in combination with 2 other classes of drug; 5-α reductase inhibitors and anti-muscarinics. AB have rapid efficacy, improving symptoms and flow rate in a matter of days, these effects are then maintained over time. AB do not impact on prostate size and do not prevent acute urinary retention or the need for surgery. Anti-mucarinics, alone or in combination with an AB are safe and efficacious in the treatment of bothersome storage symptoms associated with LUTS/BPH. Phosphodiesterase-5 inhibitors are an emerging treatment option that improve LUTS without improving flow rates. Conclusions: AB are the most well-established pharmacotherapy in the management of men with LUTS/BPH. The emergence of different classes of agent offers the opportunity to target underlying pathophysiologies driving symptoms and better individualize treatment.

  2. Management of erectile dysfunction post-radical prostatectomy

    Directory of Open Access Journals (Sweden)

    Saleh A

    2015-02-01

    Full Text Available Alan Saleh, Hamid Abboudi, MB Ghazal-Aswad, Erik K Mayer, Justin A Vale Division of Surgery and Cancer, Imperial College Healthcare NHS Trust, St Mary's Hospital, London, UK Abstract: Radical prostatectomy is a commonly performed procedure for the treatment of localized prostate cancer. One of the long-term complications is erectile dysfunction. There is little consensus on the optimal management; however, it is agreed that treatment must be prompt to prevent fibrosis and increase oxygenation of penile tissue. It is vital that patient expectations are discussed, a realistic time frame of treatment provided, and treatment started as close to the prostatectomy as possible. Current treatment regimens rely on phosphodiesterase 5 inhibitors as a first-line therapy, with vacuum erection devices and intraurethral suppositories of alprostadil as possible treatment combination options. With nonresponders to these therapies, intracavernosal injections are resorted to. As a final measure, patients undergo the highly invasive penile prosthesis implantation. There is no uniform, objective treatment program for erectile dysfunction post-radical prostatectomy. Management plans are based on poorly conducted and often underpowered studies in combination with physician and patient preferences. They involve the aforementioned drugs and treatment methods in different sequences and doses. Prospective treatments include dietary supplements and gene therapy, which have shown promise with there proposed mechanisms of improving erectile function but are yet to be applied successfully in human patients. Keywords: erectile dysfunction, phosphodiesterase 5 inhibitors, vacuum erection devices, intraurethral suppositories, intracavernosal injections

  3. Sexual function in patients with chronic angina pectoris.

    Science.gov (United States)

    Kloner, Robert A; Henderson, Luana

    2013-06-01

    Drugs for erectile dysfunction (ED) may be contraindicated with nitrates commonly used to treat patients with angina pectoris, and certain antianginal therapies may worsen ED. The American Heart Association and the Princeton Consensus Conference panel of experts recommend that patients with coronary artery disease and ED who experience angina pectoris undergo full medical evaluations to assess the cardiovascular risks associated with resuming sexual activity before being prescribed therapy for ED. Current antianginal therapies include β blockers, calcium channel blockers, short- and long-acting nitrates, and ranolazine, a late sodium current inhibitor. Short- and long-acting nitrates remain a contraindication with phosphodiesterase-5 inhibitors commonly used to treat patients with ED, and the benefits of the other antianginal therapies must be weighed against their effects on cardiovascular health and erectile function. In conclusion, patients with coronary artery disease and ED who wish to initiate phosphodiesterase-5 inhibitor therapy and need to discontinue nitrate therapy need treatment options that manage their angina pectoris effectively, maintain their cardiovascular health, and provide the freedom to maintain their sexual function. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Emerging drugs for the treatment of erectile dysfunction.

    Science.gov (United States)

    Peak, Taylor C; Yafi, Faysal A; Sangkum, Premsant; Hellstrom, Wayne J G

    2015-06-01

    Erectile dysfunction adversely affects the lives of millions of men, and is the most commonly treated sexual disorder today. The erectile process has been extensively investigated, with major advances made in elucidating many of the complex molecular pathways involved. These advances have allowed researchers to design and study drug formulations that target various aspects of this complex process. The initial culmination of this research was the introduction of phosphodiesterase 5-inhibitors. While effective in many patients, they are not satisfactory for all afflicted men. As a result, researchers are developing novel drugs that target different molecular pathways. The paper will review these pathways, and the potential agents that target them. More specifically, first dopaminergic and melanocortin receptor agonists that act centrally will be covered. Then, the paper will examine the "second-generation" phosphodiesterase 5-inhibitors, soluble guanylate cyclases, rho-kinase inhibitors, and maxi-k channel activators that act peripherally. Most of these novel drugs have yet to reach Phase III studies. However, it is likely that in years to come, patients will be selectively treated with these novel agents as a monotherapy or in combination with others acting in a synergistic manner.

  5. Translational Perspective on the Role of Testosterone in Sexual Function and Dysfunction.

    Science.gov (United States)

    Podlasek, Carol A; Mulhall, John; Davies, Kelvin; Wingard, Christopher J; Hannan, Johanna L; Bivalacqua, Trinity J; Musicki, Biljana; Khera, Mohit; González-Cadavid, Nestor F; Burnett, Arthur L

    2016-08-01

    The biological importance of testosterone is generally accepted by the medical community; however, controversy focuses on its relevance to sexual function and the sexual response, and our understanding of the extent of its role in this area is evolving. To provide scientific evidence examining the role of testosterone at the cellular and molecular levels as it pertains to normal erectile physiology and the development of erectile dysfunction and to assist in guiding successful therapeutic interventions for androgen-dependent sexual dysfunction. In this White Paper, the Basic Science Committee of the Sexual Medicine Society of North America assessed the current basic science literature examining the role of testosterone in sexual function and dysfunction. Testosterone plays an important role in sexual function through multiple processes: physiologic (stimulates activity of nitric oxide synthase), developmental (establishes and maintains the structural and functional integrity of the penis), neural (development, maintenance, function, and plasticity of the cavernous nerve and pelvic ganglia), therapeutically for dysfunctional regulation (beneficial effect on aging, diabetes, and prostatectomy), and phosphodiesterase type 5 inhibition (testosterone supplement to counteract phosphodiesterase type 5 inhibitor resistance). Despite controversies concerning testosterone with regard to sexual function, basic science studies provide incontrovertible evidence for a significant role of testosterone in sexual function and suggest that properly administered testosterone therapy is potentially advantageous for treating male sexual dysfunction. Published by Elsevier Inc.

  6. Treatment of esophageal motility disorders based on the chicago classification.

    Science.gov (United States)

    Maradey-Romero, Carla; Gabbard, Scott; Fass, Ronnie

    2014-12-01

    The Chicago Classification divides esophageal motor disorders based on the recorded value of the integrated relaxation pressure (IRP). The first group includes those with an elevated mean IRP that is associated with peristaltic abnormalities such as achalasia and esophagogastric junction outflow obstruction. The second group includes those with a normal mean IRP that is associated with esophageal hypermotility disorders such as distal esophageal spasm, hypercontractile esophagus (jackhammer esophagus), and hypertensive peristalsis (nutcracker esophagus). The third group includes those with a normal mean IRP that is associated with esophageal hypomotility peristaltic abnormalities such as absent peristalsis, weak peristalsis with small or large breaks, and frequent failed peristalsis. The therapeutic options vary greatly between the different groups of esophageal motor disorders. In achalasia patients, potential treatment strategies comprise medical therapy (calcium channel blockers, nitrates, and phosphodiesterase 5 inhibitors), endoscopic procedures (botulinum toxin A injection, pneumatic dilation, or peroral endoscopic myotomy) or surgery (Heller myotomy). Patients with a normal IRP and esophageal hypermotility disorder are candidates for medical therapy (nitrates, calcium channel blockers, phosphodiesterase 5 inhibitors, cimetropium/ipratropium bromide, proton pump inhibitors, benzodiazepines, tricyclic antidepressants, trazodone, selective serotonin reuptake inhibitors, and serotonin-norepinephrine reuptake inhibitors), endoscopic procedures (botulinum toxin A injection and peroral endoscopic myotomy), or surgery (Heller myotomy). Lastly, in patients with a normal IRP and esophageal hypomotility disorder, treatment is primarily focused on controlling the presence of gastroesophageal reflux with proton pump inhibitors and lifestyle modifications (soft and liquid diet and eating in the upright position) to address patient's dysphagia.

  7. cAMP-Signalling Regulates Gametocyte-Infected Erythrocyte Deformability Required for Malaria Parasite Transmission.

    Directory of Open Access Journals (Sweden)

    Ghania Ramdani

    2015-05-01

    Full Text Available Blocking Plasmodium falciparum transmission to mosquitoes has been designated a strategic objective in the global agenda of malaria elimination. Transmission is ensured by gametocyte-infected erythrocytes (GIE that sequester in the bone marrow and at maturation are released into peripheral blood from where they are taken up during a mosquito blood meal. Release into the blood circulation is accompanied by an increase in GIE deformability that allows them to pass through the spleen. Here, we used a microsphere matrix to mimic splenic filtration and investigated the role of cAMP-signalling in regulating GIE deformability. We demonstrated that mature GIE deformability is dependent on reduced cAMP-signalling and on increased phosphodiesterase expression in stage V gametocytes, and that parasite cAMP-dependent kinase activity contributes to the stiffness of immature gametocytes. Importantly, pharmacological agents that raise cAMP levels in transmissible stage V gametocytes render them less deformable and hence less likely to circulate through the spleen. Therefore, phosphodiesterase inhibitors that raise cAMP levels in P. falciparum infected erythrocytes, such as sildenafil, represent new candidate drugs to block transmission of malaria parasites.

  8. Cyclic guanosine monophosphate in the regulation of the cell function

    Directory of Open Access Journals (Sweden)

    Małgorzata Zbrojkiewicz

    2016-12-01

    Full Text Available Intracellular concentration of cGMP depends on the activity of guanylate cyclase, responsible for its synthesis, on the activity of cyclic nucleotide degrading enzymes - phosphodiesterases (PDEs. There are two forms of guanylate cyclase: the membrane-bound cyclase and the soluble form. The physiological activators of the membrane guanylate cyclase are natriuretic peptides (NPs, and of the cytosolic guanylate cyclase - nitric oxide (NO and carbon monoxide (CO. Intracellular cGMP signaling pathways arise from its direct effect on the activity of G protein kinases, phosphodiesterases and cyclic nucleotide dependent cation channels. It has been shown in recent years that cGMP can also affect other signal pathways in cell signaling activity involving Wnt proteins and sex hormones. The increased interest in the research on the role of cGMP, resulted also in the discovery of its role in the regulation of phototransduction in the eye, neurotransmission, calcium homeostasis, platelet aggregation, heartbeat, bone remodeling, lipid metabolism and the activity of the cation channels. Better understanding of the mechanisms of action of cGMP in the regulation of cell function can create new opportunities for the cGMP affecting drugs use in the pharmacotherapy.

  9. Malaria parasite cGMP-dependent protein kinase regulates blood stage merozoite secretory organelle discharge and egress.

    Directory of Open Access Journals (Sweden)

    Christine R Collins

    2013-05-01

    Full Text Available The malaria parasite replicates within an intraerythrocytic parasitophorous vacuole (PV. Eventually, in a tightly regulated process called egress, proteins of the PV and intracellular merozoite surface are modified by an essential parasite serine protease called PfSUB1, whilst the enclosing PV and erythrocyte membranes rupture, releasing merozoites to invade fresh erythrocytes. Inhibition of the Plasmodium falciparum cGMP-dependent protein kinase (PfPKG prevents egress, but the underlying mechanism is unknown. Here we show that PfPKG activity is required for PfSUB1 discharge into the PV, as well as for release of distinct merozoite organelles called micronemes. Stimulation of PfPKG by inhibiting parasite phosphodiesterase activity induces premature PfSUB1 discharge and egress of developmentally immature, non-invasive parasites. Our findings identify the signalling pathway that regulates PfSUB1 function and egress, and raise the possibility of targeting PfPKG or parasite phosphodiesterases in therapeutic approaches to dysregulate critical protease-mediated steps in the parasite life cycle.

  10. Torsades de Pointes

    Directory of Open Access Journals (Sweden)

    Richard J Chen, MD

    2018-04-01

    Full Text Available History of present illness: 70-year-old male with a history ventricular arrhythmia, AICD (automated implantable cardioverter defibrillator, coronary artery disease and cardiac stents presented to the Emergency Department after three AICD discharges with dyspnea but no chest pain. During triage, he was found to have an irregular radial pulse and was placed on a cardiac monitor. Significant findings: The patient was found to be in a polymorphic ventricular tachycardia; he was alert, awake and asymptomatic. A rhythm strip showed a wide complex tachycardia with the QRS complex varying in amplitude around the isoelectric line consistent with Torsades de Pointes. Discussion: Torsades de Pointes (TdP is a specific type of polymorphic ventricular tachycardia. The arrhythmia’s characteristic morphology consists of the QRS complex “twisting” around the isoelectric line with gradual variation of the amplitude, reflecting its literal translation of “twisting of the points.”1 This arrhythmia occurs in the context of prolonged QT. The most common form of acquired QT prolongation is medication induced. Common causes include antiarrhythmics, antipsychotics, antiemetics, and antibiotics.2 Patient specific risk factors include female sex, bradycardia, hypokalemia, hypomagnesemia, hypocalcemia, hypothermia and heart disease.3 In the setting of prolonged QT, the repolarization phase is extended. TdP is initiated when a PVC (premature ventricular contraction occurs during this repolarization, known as an ‘R on T’ phenomenon. TdP is often asymptomatic and self-limited. The danger in TdP is its potential to deteriorate into ventricular fibrillation. A mainstay of management of TdP is prevention of risk factors when possible.4 Unstable patients should be treated with synchronized cardioversion. Magnesium sulfate should be administered in all cases of TdP.1 If a patient is not responsive to magnesium, consider isoproterenol, amiodarone, and overdrive pacing. Since this patient was asymptomatic, he was given 2gm of magnesium sulfate and placed on an amiodarone infusion, after which Tdp terminated with a resulting sinus rhythm. AICD interrogation showed multiple episodes of ventricular fibrillation. The patient was admitted for further management and to determine why his AICD was not functioning properly. Topics: EKG, ECG, cardiology, ventricular tachycardia, arrhythmia, Torsades de Pointes

  11. Silodosin in the management of lower urinary tract symptoms as a result of benign prostatic hyperplasia: who are the best candidates.

    Science.gov (United States)

    Capitanio, U; Salonia, A; Briganti, A; Montorsi, F

    2013-06-01

    As the clinical effects of the available α1-adrenoceptors (ARs) blockers are usually considered comparable for treatment in patients suffering from lower urinary tract symptoms (LUTS) secondary to prostatic enlargement, officially recognised guidelines do not make specific recommendations regarding the choice of which agent should be considered according to the patient's characteristics. To analyse data supporting the use of silodosin, a highly selective once-daily dosing α1-ARs blocker, in different daily clinical practice scenarios. A structured literature review was performed using data retrieved from articles assessing the role of silodosin in the management of LUTS secondary to benign prostatic hyperplasia (BPH). A literature search of English language publications was performed using MEDLINE(®) and Web of Science from 2000 to 2012 using the terms LUTS; BPH; silodosin; α1-ARs blockers. The papers with the highest level of evidence were identified and represent the basis of the present review. Available data coming from basic research analyses, randomised trials and prospective studies showed that silodosin is efficacious for the initial management of patients with LUTS. Clinical developmental safety data from patients receiving silodosin with concomitant antihypertensive therapy do not indicate an increase in risk of orthostatic hypotension. In this context, a recent study demonstrated that silodosin can be safely administered to patients who are consensually assuming phosphodiesterase type 5 inhibitors. A recent randomised crossover study comparing the efficacy of silodosin and tamsulosin in patients with LUTS showed that further significant improvement was observed after switching to silodosin treatment, while worsening or little improvement was observed after switching to tamsulosin treatment. Preliminary results seem to demonstrate a potential role of silodosin in the treatment of chronic prostatitis/chronic pelvic pain syndrome and to facilitate

  12. Roles of PDE1 in Pathological Cardiac Remodeling and Dysfunction.

    Science.gov (United States)

    Chen, Si; Knight, Walter E; Yan, Chen

    2018-04-23

    Pathological cardiac hypertrophy and dysfunction is a response to various stress stimuli and can result in reduced cardiac output and heart failure. Cyclic nucleotide signaling regulates several cardiac functions including contractility, remodeling, and fibrosis. Cyclic nucleotide phosphodiesterases (PDEs), by catalyzing the hydrolysis of cyclic nucleotides, are critical in the homeostasis of intracellular cyclic nucleotide signaling and hold great therapeutic potential as drug targets. Recent studies have revealed that the inhibition of the PDE family member PDE1 plays a protective role in pathological cardiac remodeling and dysfunction by the modulation of distinct cyclic nucleotide signaling pathways. This review summarizes recent key findings regarding the roles of PDE1 in the cardiac system that can lead to a better understanding of its therapeutic potential.

  13. Presence of cyclic adenosine-3':5'-monophosphate (cAMP) in primary shoots of Zea mays L

    International Nuclear Information System (INIS)

    Edlich, W.; Graeser, H.

    1978-01-01

    The concentration of cAMP was determined in extracts of crude homogenates of maize seedlings, 3800 . g supernatants and isolated chloroplasts by the isotope dilution test. After extractpurification by precipitation with BaSO 4 and by chromatography on aluminium oxide column, a factor by means of which the binding of [8- 3 H]-cAMP with cAMP-dependent protein kinase was inhibited. The inhibitor was found inactive after treatment of the extracts with phosphodiesterase. In conclusion, this factor was identical with cAMP. It is suggested that cAMP-synthesis is localized in chloroplasts. Microbial contaminations which might disturb the detection of cAMP was excluded at least in the preparations of chloroplasts. (author)

  14. Cerebral haemodynamic response or excitability is not affected by sildenafil

    DEFF Research Database (Denmark)

    Kruuse, Christina Rostrup; Hansen, Adam E; Larsson, Henrik B W

    2009-01-01

    Sildenafil (Viagra), a cyclic guanosine monophosphate-degrading phosphodiesterase 5 inhibitor, induces headache and migraine. Such headache induction may be caused by an increased neuronal excitability, as no concurrent effect on cerebral arteries is found. In 13 healthy females (23+/-3 years, 70......) were performed. The measurements were applied at baseline and at both 1 and 2 h after ingestion of 100 mg of sildenafil. Blood pressure, heart rate and side effects, including headache, were obtained. Headache was induced in all but one subject on both study days. Sildenafil did not affect VEP...... amplitude or latency (P100). The fMRI response to visual stimulation or hypercapnia was unchanged by sildenafil. In conclusion, sildenafil induces mild headache without potentiating a neuronal or local cerebrovascular visual response or a global cerebrovascular hypercapnic response. The implication...

  15. Crystallization and preliminary X-ray diffraction analysis of rat autotaxin

    International Nuclear Information System (INIS)

    Day, Jacqueline E.; Hall, Troii; Pegg, Lyle E.; Benson, Timothy E.; Hausmann, Jens; Kamtekar, Satwik

    2010-01-01

    Autotaxin (ATX), a pyrophosphatase/phosphodiesterase enzyme, is a promising drug target for many indications and is only distantly related to enzymes of previously determined structure. Here, the cloning, expression, purification, crystallization and preliminary diffraction analysis of ATX are reported. Rat autotaxin has been cloned, expressed, purified to homogeneity and crystallized via hanging-drop vapour diffusion using PEG 3350 as precipitant and ammonium iodide and sodium thiocyanate as salts. The crystals diffracted to a maximum resolution of 2.05 Å and belonged to space group P1, with unit-cell parameters a = 53.8, b = 63.3, c = 70.5 Å, α = 98.8, β = 106.2, γ = 99.8°. Preliminary X-ray diffraction analysis indicated the presence of one molecule per asymmetric unit, with a solvent content of 47%

  16. Control of the renal renin system by local factors

    DEFF Research Database (Denmark)

    Wagner, C; Jensen, B L; Krämer, B K

    1998-01-01

    prostanoid, both stimulate renin secretion and renin gene expression by activating cAMP formation in JG cells. Although the direct effect of NO on JG cells is less clear, its overall effect in vivo seems to be to stimulate the renin system. Evidence is emerging that stimulation by NO is related to the c......AMP pathway, and cGMP-induced inhibition of cAMP-phosphodiesterase III (PDE-III) may mediate this effect. ETs, on the other hand, appear to inhibit the renin system, in particular in those pathways activated by cAMP, acting via Ca2+- and protein kinase C-related mechanisms. There is increasing evidence...... that both NO and PGs could be involved in the physiological regulatory mechanisms by which salt intake affects the renin system....

  17. Toxicological evaluation of a dietary supplement formulated for male sexual health prior to market release.

    Science.gov (United States)

    Clewell, A; Qureshi, I; Endres, J; Horváth, J; Financsek, I; Neal-Kababick, J; Jade, K; Schauss, A G

    2010-06-01

    The dietary supplement, 112 Degrees, was formulated with the goal of supporting sexual functioning in men. Due to rampant problems with drug adulteration for this category of products, a comprehensive screening for active pharmaceutical agents, with an emphasis on drugs prescribed for erectile dysfunction such as type 5 phosphodiesterase (PDE-5) inhibitors, and known unapproved PDE-5 drug analogues, was performed along with preclinical toxicology studies prior to the introduction of this product into the marketplace. 112 Degrees was found to be free of all pharmaceutical adulterants tested, and was not mutagenic, clastogenic, or genotoxic as demonstrated by the Ames test, chromosomal aberration assay, and mouse micronucleus assay, respectively. The LD(50) in the 14-day acute oral toxicity study was greater than 5000 mg/kg, the highest dose tested. (c) 2009 Elsevier Inc. All rights reserved.

  18. Coadjuvants in the Diabetic Complications: Nutraceuticals and Drugs with Pleiotropic Effects

    Directory of Open Access Journals (Sweden)

    Thiago Melo Costa Pereira

    2016-08-01

    Full Text Available Because diabetes mellitus (DM is a multifactorial metabolic disease, its prevention and treatment has been a constant challenge for basic and clinical investigators focused on translating their discoveries into clinical treatment of this complex disorder. In this review, we highlight recent experimental and clinical evidences of potential coadjuvants in the management of DM, such as polyphenols (quercetin, resveratrol and silymarin, cultured probiotic microorganisms and drugs acting through direct/indirect or pleiotropic effects on glycemic control in DM. Among several options, we highlight new promising therapeutic coadjuvants, including chemical scavengers, the probiotic kefir and the phosphodiesterase 5 inhibitors, which besides the reduction of hyperglycemia and ameliorate insulin resistance, they reduce oxidative stress and improve endothelial dysfunction in the systemic vascular circulation. In the near future, experimental studies are expected to clear the intracellular pathways involving coadjuvants. The design of clinical trials may also contribute to new strategies with coadjuvants against the harmful effects of diabetic complications.

  19. Synthesis of diadenosine 5', 5'''-P1, P4-tetraphosphate (AP4A) in sea urchin embryos

    International Nuclear Information System (INIS)

    Morioka, Mizue; Shimada, Hiraku

    1984-01-01

    Sea urchin embryos were labeled with ( 3 H)adenosine at two developmental stages (morula and prism) and the labeled acid-soluble nucleotides were fractionated successively by column chromatography with DEAE-Sephadex and DEAE-cellulose, and by thin-layer chromatography on a PEI-cellulose plate. Significant radioactivity was detected on the PEI-cellulose plate at the region of diadenosine 5', 5'''-P 1 , P 4 -tetraphosphate (AP 4 A). After treatment of this fraction with phosphodiesterase, the radioactivity was all recovered in the AMP region, while alkaline phosphatase had no effect on the AP 4 A fraction. The present result suggests that AP 4 A is actively synthesized in the sea urchin embryos. (author)

  20. The reduction of radiation-induced mitotic delay by caffeine: a test of the cyclic AMP hypothesis

    International Nuclear Information System (INIS)

    Oleinick, N.L.; Brewer, E.N.; Rustad, R.C.

    1978-01-01

    A study has been made of the reduction in γ-radiation-induced mitotic delay by caffeine in the naturally-synchronous plasmodial slime mould. Physarum polycephalum during late G 2 and early prophase, and the results compared with those obtained with other compounds of similar structure and/or physiological function. The reduction of radiation-induced mitotic delay was related to increasing concentrations of caffeine over at least two orders of magnitude. Pre-irradiation treatment with caffeine had no detectable effect. Caffeine had to be present for most, if not all, of the post-irradiation pre-mitotic period. Other chemicals which are reported to inhibit cyclic AMP phosphodiesterase either reduce or increase radiation-induced mitotic delay. The results therefore indicate that the reduction of mitotic delay by caffeine is not a result of altered cyclic AMP levels. (UK)

  1. Effects of caffeine on protein phosphorylation and cell cycle progression in X-irradiated two-cell mouse embryos

    International Nuclear Information System (INIS)

    Jung, Th.; Streffer, C.

    1992-01-01

    To understand the mechanism of the caffeine-induced uncoupling of mitosis and the cellular reactions to DNA-damaging agents, the authors studied the effects of caffeine treatment on cell cycle progression and protein phosphorylation in two-cell mouse embryos after X-irradiation. Caffeine alone had no effect on timing of and changes in phosphorylation associated with the embryonic cell cycle. In combination with X-rays, caffeine was able to override the radiation induced G 2 block and restored normal timing of these phosphorylation changes after X-irradiation. New additional changes in protein phosphorylation appeared after the combined treatment. Isobutyl-methylxanthine (IBMX), a substance chemically related to caffeine but a more specific inhibitor of the phosphodiesterase that breaks down cyclic AMP, reduced radiation induced G 2 block from 4 to 5 h to about 1 h and restored the cell cycle associated changes in protein phosphorylation. (author)

  2. Effect of the caffeine on treated and non-treated plasmid DNA with stannic chloride; Efeito da cafeina em DNA plasmidial tratado e nao tratado com cloreto estanoso

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, Silvana Ramos F. [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Biologia. Dept. de Biofisica e Biometria]|[Universidade Federal Fluminense, Niteroi, RJ (Brazil). Faculdade de Ciencias Medicas. Curso de Pos-graduacao em Patologia Experimental; Mattos, Jose C.P. de; Dantas, Flavio; Araujo, Adriano Caldeira de; Bernardo-Filho, Mario [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Biologia. Dept. de Biofisica e Biometria]. E-mail: bernardo@uerj.br

    2000-07-01

    Caffeine, a methilxantine drug is a component of coffee, tea, stimulants and other drinks. Caffeine inhibits phosphodiesterase leading to intracellular accumulation of cyclic AMP, blocks adenosine receptors, and increases the release of Ca{sup 2+}. We have studied the possible effect of caffeine in DNA plasmid treated or not with stannous chloride (SnCl{sub 2}). Previous evaluations of the effect of caffeine on the labeling of red blood cells and plasma proteins with technetium-99m have showed a decrease of % ATI in the insoluble fraction of plasma proteins. Samples of DNA were treated with SnCl{sub 2} (0 and 200{mu}g/ml) in 0.8% agarose. SnCl{sub 2} has induced break on DNA and caffeine has not showed effect on the DNA. This indicates that caffeine does not eliminate the oxidant action of SnCl{sub 2} and does not promote break in isolated DNA plasmid. (author)

  3. A large replication study and meta-analysis in European samples provides further support for association of AHI1 markers with schizophrenia

    DEFF Research Database (Denmark)

    Ingason, Andrés; Giegling, Ina; Cichon, Sven

    2010-01-01

    The Abelson helper integration site 1 (AHI1) gene locus on chromosome 6q23 is among a group of candidate loci for schizophrenia susceptibility that were initially identified by linkage followed by linkage disequilibrium mapping, and subsequent replication of the association in an independent sample....... Here, we present results of a replication study of AHI1 locus markers, previously implicated in schizophrenia, in a large European sample (in total 3907 affected and 7429 controls). Furthermore, we perform a meta-analysis of the implicated markers in 4496 affected and 18,920 controls. Both...... as the neighbouring phosphodiesterase 7B (PDE7B)-may be considered candidates for involvement in the genetic aetiology of schizophrenia....

  4. Coadjuvants in the Diabetic Complications: Nutraceuticals and Drugs with Pleiotropic Effects

    Science.gov (United States)

    Pereira, Thiago Melo Costa; Pimenta, Fabio Silva; Porto, Marcella Lima; Baldo, Marcelo Perim; Campagnaro, Bianca Prandi; Gava, Agata Lages; Meyrelles, Silvana Santos; Vasquez, Elisardo Corral

    2016-01-01

    Because diabetes mellitus (DM) is a multifactorial metabolic disease, its prevention and treatment has been a constant challenge for basic and clinical investigators focused on translating their discoveries into clinical treatment of this complex disorder. In this review, we highlight recent experimental and clinical evidences of potential coadjuvants in the management of DM, such as polyphenols (quercetin, resveratrol and silymarin), cultured probiotic microorganisms and drugs acting through direct/indirect or pleiotropic effects on glycemic control in DM. Among several options, we highlight new promising therapeutic coadjuvants, including chemical scavengers, the probiotic kefir and the phosphodiesterase 5 inhibitors, which besides the reduction of hyperglycemia and ameliorate insulin resistance, they reduce oxidative stress and improve endothelial dysfunction in the systemic vascular circulation. In the near future, experimental studies are expected to clear the intracellular pathways involving coadjuvants. The design of clinical trials may also contribute to new strategies with coadjuvants against the harmful effects of diabetic complications. PMID:27527163

  5. The treatment of erectile dysfunction in patients with neurogenic disease.

    Science.gov (United States)

    Shridharani, Anand N; Brant, William O

    2016-02-01

    Erectile dysfunction (ED) related to compromise of the nervous system is an increasingly common occurrence. This may be due to the multifactorial nature of ED, the myriad of disorders affecting the neurotransmission of erectogenic signals, and improved awareness and diagnosis of ED. Nevertheless, neurogenic ED remains poorly understood and characterized. Disease related factors such as depression, decreased physical and mental function, the burden of chronic illness, and loss of independence may preclude sexual intimacy and lead to ED as well. The amount of data regarding treatment options in subpopulations of differing neurologic disorders remains scarce except for men with spinal cord injury. The treatment options including phosphodiesterase inhibitors, intracavernosal or intraurethral vasoactive agents, vacuum erection devices (VED) and penile prosthetic implantation remain constant. This review discusses the options in specific neurologic conditions, and briefly provides insight into new and future developments that may reshape the management of neurogenic ED.

  6. Insulin release by glucagon and secretin

    DEFF Research Database (Denmark)

    Kofod, Hans; Andreu, D; Thams, P

    1988-01-01

    Secretin and glucagon potentiate glucose-induced insulin release. We have compared the effects of secretin and glucagon with that of four hybrid molecules of the two hormones on insulin release and formation of cyclic AMP (cAMP) in isolated mouse pancreatic islets. All six peptides potentiated...... the release of insulin at 10 mM D-glucose, and their effects were indistinguishable with respect to the dynamics of release, dose-response relationship, and glucose dependency. However, measurements of cAMP accumulation in the presence of the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (10(-4) M...... potentiating effects of secretin and glucagon on glucose-induced insulin release, their modes of action may be different....

  7. Acute Intracranial and Spinal Subdural Hematoma Associated with Vardenafil.

    Science.gov (United States)

    Nakamura, Takaaki; Watanabe, Genya; Harada, Ryuhei; Kawasaki, Emiko; Tsukita, Kenichi; Suzuki, Yasushi

    2018-05-02

    A 28-year-old healthy man was admitted to our hospital because of right-sided headache, vomiting, and lower back pain after the administration of vardenafil. Computed tomography and magnetic resonance imaging of the brain showed a small, right-sided, subdural hematoma. A lumbar magnetic resonance imaging showed a longitudinally extended subdural hematoma. He had no history of trauma. We speculated that vardenafil might have had an association with the bleeding. Several reports have suggested a relationship between phosphodiesterase-5 inhibitors and intracerebral or subarachnoid hemorrhage. Our case suggested that there may also be risks of bleeding into the subdural space. Although headache and nausea are common side effects of vardenafil, hemorrhagic diseases should also be considered when symptoms are severe or prolonged. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  8. Serodiagnosis of Borrelia miyamotoi disease by measuring antibodies against GlpQ and variable major proteins

    DEFF Research Database (Denmark)

    Koetsveld, J.; Kolyasnikova, N. M.; Wagemakers, A.

    2018-01-01

    previously shown the differential expression of antigenic variable major proteins (Vmps) in B. miyamotoi, our aim was to study antibody responses against GlpQ and Vmps in PCR-proven BMD patients and controls. Methods: We assessed seroreactivity against GlpQ and four Vmps in a well-described, longitudinal......, and IgG between 21 and 50 days, after disease onset. Various combinations of GlpQ and Vmps increased sensitivity and/or specificity compared to single antigens. Notably, the GlpQ or variable large protein (Vlp)-15/16 combination yielded a sensitivity of 94.7% (95% CI: 75.4–99.7) 11–20 days after disease......Objectives: Borrelia miyamotoi disease (BMD) is an emerging tick-borne disease in the Northern hemisphere. Serodiagnosis by measuring antibodies against glycerophosphodiester-phosphodiesterase (GlpQ) has been performed experimentally but has not been extensively clinically validated. Because we had...

  9. Daily tadalafil for the chronic phase of stuttering priapism: a case report.

    Science.gov (United States)

    Massenio, Paolo; D'Altilia, Nicola; Sanguedolce, Francesca; Carrieri, Giuseppe; Cormio, Luigi

    2018-05-31

    Recurrent (stuttering) ischemic priapism is a challenging clinical condition. Frequent recurrences result in frequent hospital admissions whereas treatment with a shunting procedure often results in erectile dysfunction. A 22-year-old man with stuttering idiopathic priapism developed erectile dysfunction (IIEF-5 score 12) following a Winter's shunt; he was given tadalafil, 5 mg/daily, for 6 months. This treatment resulted in progressive restoration of erectile function in the 6 months following the shunt as well as in preventing recurrence of priapic episodes over a 24-month follow-up. This is the first report in literature of chronic treatment of stuttering priapism with a phosphodiesterase-5 inhibitor being able not only to prevent recurrent priapic episodes but also to restore erectile function following a Winter's shunt.

  10. Coccolithophores: Functional Biodiversity, Enzymes and Bioprospecting

    Directory of Open Access Journals (Sweden)

    Michael J. Allen

    2011-04-01

    Full Text Available Emiliania huxleyi is a single celled, marine phytoplankton with global distribution. As a key species for global biogeochemical cycling, a variety of strains have been amassed in various culture collections. Using a library consisting of 52 strains of E. huxleyi and an ‘in house‘ enzyme screening program, we have assessed the functional biodiversity within this species of fundamental importance to global biogeochemical cycling, whilst at the same time determining their potential for exploitation in biocatalytic applications. Here, we describe the screening of E. huxleyi strains, as well as a coccolithovirus infected strain, for commercially relevant biocatalytic enzymes such as acid/alkali phosphodiesterase, acid/alkali phosphomonoesterase, EC1.1.1-type dehydrogenase, EC1.3.1-type dehydrogenase and carboxylesterase.

  11. Static magnetic field changes the activity of venom phospholipase of Vipera Lebetina snakes

    International Nuclear Information System (INIS)

    Garibova, L.S.; Avetisyan, T.O.; Ajrapetyan, S.N.

    2000-01-01

    The effect of the static magnetic field (SMF) on the phospholipid activity of the class-A snake venom is studied. The Vipera Lebetina snake venom was subjected during 10 days to 30 minute impact of the CMF daily. It is established that increase in the phospholipase A 1 and A 2 approximately by 21 and 32 % correspondingly and in the phosphodiesterase C - by 33 % was observed. The decrease in the total protein level of the snake venom by 31.6 ± 2.2 % was noted thereby. It may be assumed that the described phospholipase and phosphoesterase changes may lead to essential shifts in the total metabolic activity of cells and organism as a whole. The activity index of these ferments may serve as an indicator of changes in the environmental magnetic field [ru

  12. Use of gamma irradiated viper venom as the toxoid against viper venom poisoning in mice and rabbits

    International Nuclear Information System (INIS)

    Hati, A.K.; Mandal, M.; Hati, R.N.; Das, S.

    1995-01-01

    The present paper deals with detoxification of the crude viper (Vipera russelli) venom by gamma irradiation and its effective immunogenic role in Balb/C mice, used as a toxoid. The successful immunization of rabbits with irradiated viper venom toxoid is also reported. Certain biochemical changes of the venom due to radiation exposure and neutralization capacity of the immune sera against phosphodiesterase and protease activity of the crude viper venom have also been studied. The neutralizing potency of Russell's viper venom (RVV) toxoid anti venom (anti venom raised in rabbits against γ-irradiated RVV toxoid adsorbed on aluminium phosphate), in comparison with a commercial bivalent anti venom (as a standard reference) with reference to haemorrhagic, necrotic and lethal effects of Russell's viper envenomation are reported. 25 refs

  13. The efficacy and safety of on-demand Elonza; a generic product of sildenafil in Thai men with erectile dysfunction.

    Science.gov (United States)

    Wijitsettakul, Udomsak; Pempongkosol, Sompol

    2013-06-01

    To evaluate the efficacy and safety of Elonza (generic product of sildenafil) 100 mg, a phosphodiesterase type 5 (PDE5) inhibitor, in Thai men with erectile dysfunction (ED). This prospective, Cohort study was conducted for eight weeks. Two hundred ten male patients, older than 20 years of age with ED were enrolled to receive generic product of sildenafil 100 mg taken as needed. Efficacy is evaluated through the International Index of Erectile Function (IIEF) scores for the five separate response domains, erectile function, orgasmic function, sexual desire, intercourse satisfaction, and overall satisfaction domain. After sildenafil administration, erectile function domain scores were significantly increased from baseline, 5.02 (p product of sildenafil, was an effective and well-tolerated treatment for ED in Thai men.

  14. Urease inhibition potential of Di-naphthodiospyrol from Diospyros lotus roots.

    Science.gov (United States)

    Rauf, Abdur; Uddin, Ghias; Raza, Muslam; Patel, Seema; Bawazeer, Saud; Ben Hadda, Taibi; Jehan, Noor; Mabkhot, Yahia Nasser; Khan, Ajmal; Mubarak, Mohammad S

    2017-05-01

    The dimeric napthoquione 5,8,4'-trihydroxy-1'-methoxy-6, 6'-dimethyl-7,3'-binaphtyl-1,4,5',8'-tetraone (1) was isolated from the chloroform fraction of Diospyros lotus extract. Compound 1 was screened for its inhibitory effects against four enzymes: urease, phosphodiesterase-I, carbonic anhydrase-II and α-chymotrypsin, and showed selective activity against urease enzyme with an IC 50 value of 254.1 ± 3.82 μM as compared to the standard thiourea (IC 50  = 21 ± 0.11 μM). Furthermore, in silico docking study was carried out to explain the molecular mechanism of compound 1 against the target receptor.

  15. Peyronie's Reconstruction for Maximum Length and Girth Gain: Geometrical Principles

    Directory of Open Access Journals (Sweden)

    Paulo H. Egydio

    2008-01-01

    Full Text Available Peyronie's disease has been associated with penile shortening and some degree of erectile dysfunction. Surgical reconstruction should be based on giving a functional penis, that is, rectifying the penis with rigidity enough to make the sexual intercourse. The procedure should be discussed preoperatively in terms of length and girth reconstruction in order to improve patient satisfaction. The tunical reconstruction for maximum penile length and girth restoration should be based on the maximum length of the dissected neurovascular bundle possible and the application of geometrical principles to define the precise site and size of tunical incision and grafting procedure. As penile rectification and rigidity are required to achieve complete functional restoration of the penis and 20 to 54% of patients experience associated erectile dysfunction, penile straightening alone may not be enough to provide complete functional restoration. Therefore, phosphodiesterase inhibitors, self-injection, or penile prosthesis may need to be added in some cases.

  16. Heart Failure Treated with Low-dose Milrinone in a Full-term Newborn

    Directory of Open Access Journals (Sweden)

    S. Šebková

    2012-01-01

    Full Text Available A term newborn with a hypocontractile myocardium complicating persistent pulmonary hypertension of the newborn was successfully treated with a low-dose phosphodiesterase III inhibitor milrinone. Echocardiography diagnosed heart failure with a left ventricular ejection fraction of 35% and a left ventricular shortening fraction of 18% and severe persistent pulmonary hypertension of the newborn with oxygenation index of 28. Milrinone was started at an initial dose of 50 mcg/kg, followed by continuous infusion of 0.20 mcg/kg/min. With lowdose milrinone oxygenation index decreased to 3 within 6 hours, left ventricular ejection fraction and left ventricular shortening fraction increased to 57%, and 30%, respectively. Low doses of milrinone might be promising in the treatment of heart failure and persistent pulmonary hypertension of the newborn in term newborns.

  17. Inhaled therapy for the management of perioperative pulmonary hypertension

    Directory of Open Access Journals (Sweden)

    C A Thunberg

    2015-01-01

    Full Text Available Patients with pulmonary hypertension (PH are at high risk for complications in the perioperative setting and often receive vasodilators to control elevated pulmonary artery pressure (PAP. Administration of vasodilators via inhalation is an effective strategy for reducing PAP while avoiding systemic side effects, chiefly hypotension. The prototypical inhaled pulmonary-specific vasodilator, nitric oxide (NO, has a proven track record but is expensive and cumbersome to implement. Alternatives to NO, including prostanoids (such as epoprostenol, iloprost, and treprostinil, NO-donating drugs (sodium nitroprusside, nitroglycerin, and nitrite, and phosphodiesterase inhibitors (milrinone, sildenafil may be given via inhalation for the purpose of treating elevated PAP. This review will focus on the perioperative therapy of PH using inhaled vasodilators.

  18. Milrinone in Enterovirus 71 Brain Stem Encephalitis

    Directory of Open Access Journals (Sweden)

    SHIH-MIN eWANG

    2016-03-01

    Full Text Available Enterovirus 71 (EV71 was implicated in a widespread outbreak of hand-foot-and-mouth disease (HFMD across the Asia Pacific area since 1997 and has also been reported sporadically in patients with brain stem encephalitis. Neurogenic shock with pulmonary edema (PE is a fatal complication of EV71 infection. Among inotropic agents, milrinone is selected as a therapeutic agent for EV71- induced PE due to its immunopathogenesis. Milrinone is a type III phosphodiesterase inhibitor that has both inotropic and vasodilator effects. Its clinical efficacy has been shown by modulating inflammation, reducing sympathetic over-activity, and improving survival in patients with EV71-associated PE. Milrinone exhibits immunoregulatory and anti-inflammatory effects in the management of systemic inflammatory responses in severe EV71 infection.

  19. Vasodilatory effect and endothelial integrity in papaverine- and milrinone-treated human radial arteries.

    Science.gov (United States)

    Rudzinski, P; Wegrzyn, P; Lis, G J; Piatek, J; Konstanty-Kalandyk, J; Nosalski, R; Mikolajczyk, T; Jasinska, M; Pyka-Fosciak, G; Guzik, T; Litwin, J A; Korbut, R; Sadowski, J

    2013-02-01

    Prevention of the vasospasm is an important aspect of coronary artery bypass grafting (CABG) with the use of radial artery (RA) as the conduit. We compared the effect of two phosphodiesterase inhibitors papaverine and milrinone on vasodilation and endothelial integrity of human RA segments harvested from 20 CABG patients. Vasodilatory effect of the drugs were assessed by organ bath technique in RA rings precontracted with KCl and phenylephrine. Endothelial integrity was evaluated by CD34 immunofluorescence in frozen sections. Vasorelaxation induced by papaverine was significantly greater as compared to that induced by milrinone (90.47% ± 10.16% vs. 78.98% ± 19.56%, pmilrinone in the preservation of endothelial integrity (75.3% ± 12.9% vs. 51.8% ± 18.0%, pmilrinone for prevention of vasospasm in radial artery conduits used for CABG.

  20. Heart failure treated with low-dose milrinone in a full-term newborn.

    Science.gov (United States)

    Sebková, S; Tomek, V; Zemanová, P; Janota, J

    2012-01-01

    A term newborn with a hypocontractile myocardium complicating persistent pulmonary hypertension of the newborn was successfully treated with a low-dose phosphodiesterase III inhibitor milrinone. Echocardiography diagnosed heart failure with a left ventricular ejection fraction of 35% and a left ventricular shortening fraction of 18% and severe persistent pulmonary hypertension of the newborn with oxygenation index of 28. Milrinone was started at an initial dose of 50 mcg/kg, followed by continuous infusion of 0.20 mcg/kg/min. With lowdose milrinone oxygenation index decreased to 3 within 6 hours, left ventricular ejection fraction and left ventricular shortening fraction increased to 57%, and 30%, respectively. Low doses of milrinone might be promising in the treatment of heart failure and persistent pulmonary hypertension of the newborn in term newborns.

  1. Overcoming of P-glycoprotein mediated vincristine resistance of L1210/VCR mouse leukemic cells could be induced by pentoxifylline but not by theophylline and caffeine

    International Nuclear Information System (INIS)

    Stefankova, Z.; Barancik, M.; Breier, A.

    1996-01-01

    Effects of xanthine derivatives (pentoxifylline (PTX), caffeine, theophylline, 1-methyl-3-isobutylxanthine) on P-glycoprotein mediated vincristine resistance of L1210/VCR mouse leukemic cell sub-line were studied. From the applied xanthines only PTX was found to reverse the vincristine resistance of the above cells. Moreover, only PTX, but not other xanthine, increased the accumulation of [ 3 H]vincristine by L1210/VCR cells. Thus it may be concluded that PTX-induced reversal of vincristine (VCR) resistance could not be explained from the point of known pharmacological effects of PTX that are common for other xanthines such as inhibition of phosphodiesterase activity, calcium mobilizing effect, inhibition of tumor necrosis factor α (TNF), etc. (author)

  2. Novel potential for the management of Alzheimer disease.

    Science.gov (United States)

    Ginter, E; Simko, V; Weinrebova, D; Ladecka, Z

    2015-01-01

    Pathologic characteristics of Alzheimer disease (AD) are β-amyloid (Aβ) plaques, neurofibrillary tangles (NFT) and neurodegeneration. Currently, there is no cure for AD. Cilostazol, a selective inhibitor of type 3 phosphodiesterase, is likely to be a promising agent for AD. In the brain of the experimental animals it significantly reduced the Aβ amyloid plaques. Initial clinical reports on the effect of Cilostazol in AD patients are promising. In mice, stem cells favourably influence the pathogenetic process critical in AD, by reducing deposits of Aβ plaques. Clinical trials of the drug, called Betablock, are already underway in Britain. Successful management and resolution of AD in man will still require further intensive research (Fig. 4, Ref. 11).

  3. Current views on the pharmacotherapy of psoriatic arthritis

    Directory of Open Access Journals (Sweden)

    G. G. Taradin

    2015-01-01

    Full Text Available The review deals with current pharmacological approaches to treating psoriatic arthritis (PsA. It gives data on the prevalence of psoriasis and psoriatic joint injury that is a common cause of early patient disability. Approaches to evaluating the efficacy of drugs are given on the basis of developed and used criteria with regard to the standardized assessment of the dynamics of joint injury in rheumatic diseases and PSA in particular. The review gives brief information on the mechanism of drug actions and the results of clinical trials evaluating the efficacy and safety of different medicaments in PsA. It also covers the experience in using nonsteroidal antiinflammatory drugs, glucocorticoids, synthetic diseasemodifying antirheumatic drugs (methotrexate, cyclosporine, leflunomide, sulfasalazine, and also a promising group of biologicals. Particular emphasis is placed on the results of using tumor necrosis factor inhibitors (etanercept, infliximab, golimumab, certolizumab pegol, adalimumab, interleukin inhibitors (ustekinumab, brodalumab, and phosphodiesterase 4 inhibitors (apremilast.

  4. MEK Inhibitors Reverse cAMP-Mediated Anxiety in Zebrafish

    DEFF Research Database (Denmark)

    Lundegaard, Pia R.; Anastasaki, Corina; Grant, Nicola J.

    2015-01-01

    Altered phosphodiesterase (PDE)-cyclic AMP (cAMP) activity is frequently associated with anxiety disorders, but current therapies act by reducing neuronal excitability rather than targeting PDE-cAMP-mediated signaling pathways. Here, we report the novel repositioning of anti-cancer MEK inhibitors...... as anxiolytics in a zebrafish model of anxiety-like behaviors. PDE inhibitors or activators of adenylate cyclase cause behaviors consistent with anxiety in larvae and adult zebrafish. Small-molecule screening identifies MEK inhibitors as potent suppressors of cAMP anxiety behaviors in both larvae and adult...... zebrafish, while causing no anxiolytic behavioral effects on their own. The mechanism underlying cAMP-induced anxiety is via crosstalk to activation of the RAS-MAPK signaling pathway. We propose that targeting crosstalk signaling pathways can be an effective strategy for mental health disorders, and advance...

  5. Synthesis and characterization of polymeric hydrogel containing caffeine for cosmeceutical applications

    International Nuclear Information System (INIS)

    Santos, Tiago C.; Oliveira, Maria José A.; Lugão, Ademar B.

    2017-01-01

    Caffeine, a substance with belongs to the group of methylxanthines, is alkaloids that penetrate in the human epidermis but is not easily absorbed into the bloodstream. With a dermatological active substance, it exerts action on the subcutaneous adipose tissue causing adipocyte lipolysis through the inhibition of phosphodiesterase. Based on these considerations, the objective of this study was to investigate the behavior of caffeine in a polymeric hydrogel matrix, for possible cosmeceutical applications. The hydrogels were cross-linked and sterilized by Cobalt-60 source gamma irradiation. In the characterization, were used thermogravimetry (TGA), scanning electron microscopy (SEM), differential scanning calorimetry (DSC). It was possible to observe by SEM the presence of crystals in the hydrogel sample. The DSC experiment confirmed a crystallinity of the sample and that caffeine is not degraded by gamma irradiation at 25 kGy. The results were satisfactory, allowing a new investigations that certify the benefits of its application. (author)

  6. Note: A flexible light emitting diode-based broadband transient-absorption spectrometer

    Science.gov (United States)

    Gottlieb, Sean M.; Corley, Scott C.; Madsen, Dorte; Larsen, Delmar S.

    2012-05-01

    This Note presents a simple and flexible ns-to-ms transient absorption spectrometer based on pulsed light emitting diode (LED) technology that can be incorporated into existing ultrafast transient absorption spectrometers or operate as a stand-alone instrument with fixed-wavelength laser sources. The LED probe pulses from this instrument exhibit excellent stability (˜0.5%) and are capable of producing high signal-to-noise long-time (>100 ns) transient absorption signals either in a broadband multiplexed (spanning 250 nm) or in tunable narrowband (20 ns) operation. The utility of the instrument is demonstrated by measuring the photoinduced ns-to-ms photodynamics of the red/green absorbing fourth GMP phosphodiesterase/adenylyl cyclase/FhlA domain of the NpR6012 locus of the nitrogen-fixing cyanobacterium Nostoc punctiforme.

  7. [Female sexual dysfunction: Drug treatment options].

    Science.gov (United States)

    Alcántara Montero, A; Sánchez Carnerero, C I

    2016-01-01

    Many women will likely experience a sexual problem in their lifetime. Female sexual dysfunction is a broad term used to describe 3 categories of disorders of a multifactorial nature. Effective, but limited pharmacotherapeutic options exist to address female sexual dysfunction. The FDA recently approved the first agent for treatment of hypoactive sexual desire disorder in pre-menopausal women. Off-label use of hormonal therapies, particularly oestrogen and testosterone, are the most widely employed for female sexual dysfunction, particularly in post-menopausal women. Other drugs currently under investigation include phosphodiesterase inhibitors and agents that modulate dopamine or melanocortin receptors. Copyright © 2016 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

  8. Determination of sildenafil by preconcentration on surfactant coated polymeric resin followed by spectrofluorimetry

    Directory of Open Access Journals (Sweden)

    Chien C. Wang

    2013-06-01

    Full Text Available The illicit addition of phosphodiesterase type-5 (PDE-5 inhibitors like sildenafil (Viagra in product offered as herbal medicine or dietary supplement for male erectile dysfunction has concerned authorities in recent times. In this paper, we proposed a sensitive surfactant-coated Amberlite XAD™ resin for sildenafil preconcentration method with spectrofluorimetric detection. Retention capacity of micellar coated XAD resin for sildenafil was studied and the obtained eluate was measured by spectrofluorometer at excitation and emission wavelengths of 350 and 430nm, respectively. This method allowed the detection of sildenafil at 0.15ng/mL with linear range of 0.0003–7.0μg/mL. The method has been successfully applied to the analysis of some local commercially available herbal medicines and urine. Keywords: Sildenafil, Herbal medicines, Spectrofluorimetric analysis, Surfactant

  9. A new therapeutic approach for erectile dysfunction: Low intensity shockwaves

    Directory of Open Access Journals (Sweden)

    García-Perdomo, Herney Andrés

    2015-07-01

    Full Text Available Erectile dysfunction is the inability to achieve or sustain a penile erection for vaginal penetration and satisfactory sexual performance. It is the second most frequent problem of sexual dysfunction in men, after premature ejaculation, with an approximate prevalence rate of 30%. Most cases of erectile dysfunction have an organic origin, mostly vascular diseases, but it is also associated with psychological, neurological, and hormonal factors, or with structural alterations of the penis. Therapy with 5-phosphodiesterase inhibitors has been clinically effective, but some patients do not respond to it. Lowintensity shock waves may improve penile vascularity and blood flow, leading to better erections, and improvement of the quality of sexual performance. In this review several studies are included that show the effectiveness of this treatment for erectile dysfunction.

  10. Premature ejaculation. 3. Therapy.

    Science.gov (United States)

    Piediferro, Guido; Colpi, Elisabetta M; Castiglioni, Fabrizio; Scroppo, Fabrizio I

    2004-12-01

    Serotonergic drugs (SSRIs) are the most commonly used, but they are characterized by relapse some time after medication interruption as well as by sexual side effects. The efficacy of phosphodiesterase-5 inhibitors seems excellent, but the risk of tachyphylaxis has been reported. The former (fluoxetine, paroxetine, sertraline, clomipramine) should be used in young patients with hyper-orgasmic forms, while the latter (sildenafil, tadalafil, vardenafil) should be used in hypo-orgasmic forms, in old age or when PE is associated with erectile dysfunction. Topical anesthetics provide satisfactory results in premature ejaculation due to hypersensitivity of the glans, and physiotherapy of the pelvic floor muscles proves successful in cases associated with pelvic floor dysfunction. Therapeutic associations and psycho-sexual therapy techniques may improve results, particularly in the long term.

  11. Effects of the new imidazopyridine CL 86-02-01 on isolated papillary muscle of guinea-pig hearts.

    Science.gov (United States)

    Studenik, C; Lemmens-Gruber, R; Heistracher, P

    1998-06-01

    Inotropic activity and the effect of CL 86-02-01 (2-(3-methoxy-5-methylsulfinyl-2-thienyl)-1H-imidazo[4,5-c]pyridine hydrochloride, CAS 109 792-24-7) on membrane resting and action potentials were studied in isolated guinea-pig papillary muscles. Membrane resting potential and action potential parameters were not significantly changed, while CL 86-02-01 exerted a concentration-dependent inotropic effect by increasing the maximum rate of force development and maximum rate of force relaxation. Time to peak force, relaxation time and total contraction time were reduced. These effects are similar to those of beta-adrenergic drugs and phosphodiesterase inhibitors, but markedly differ from those described for other positive inotropic agents like cardiac glycosides, calcium agonists, alpha-adrenergic drugs or increased extracellular calcium concentration.

  12. Effects of caffeine on protein phosphorylation and cell cycle progression in X-irradiated two-cell mouse embryos

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Th. (AFRC Institute of Animal Physiology and Genetics Research, Babraham (United Kingdom)); Streffer, C. (Essen Univ (Germany). Inst. fuer Medizinische Strahlenbiolgie)

    1992-08-01

    To understand the mechanism of the caffeine-induced uncoupling of mitosis and the cellular reactions to DNA-damaging agents, the authors studied the effects of caffeine treatment on cell cycle progression and protein phosphorylation in two-cell mouse embryos after X-irradiation. Caffeine alone had no effect on timing of and changes in phosphorylation associated with the embryonic cell cycle. In combination with X-rays, caffeine was able to override the radiation induced G[sub 2] block and restored normal timing of these phosphorylation changes after X-irradiation. New additional changes in protein phosphorylation appeared after the combined treatment. Isobutyl-methylxanthine (IBMX), a substance chemically related to caffeine but a more specific inhibitor of the phosphodiesterase that breaks down cyclic AMP, reduced radiation induced G[sub 2] block from 4 to 5 h to about 1 h and restored the cell cycle associated changes in protein phosphorylation. (author).

  13. GDE2 regulates subtype-specific motor neuron generation through inhibition of Notch signaling.

    Science.gov (United States)

    Sabharwal, Priyanka; Lee, Changhee; Park, Sungjin; Rao, Meenakshi; Sockanathan, Shanthini

    2011-09-22

    The specification of spinal interneuron and motor neuron identities initiates within progenitor cells, while motor neuron subtype diversification is regulated by hierarchical transcriptional programs implemented postmitotically. Here we find that mice lacking GDE2, a six-transmembrane protein that triggers motor neuron generation, exhibit selective losses of distinct motor neuron subtypes, specifically in defined subsets of limb-innervating motor pools that correlate with the loss of force-generating alpha motor neurons. Mechanistically, GDE2 is expressed by postmitotic motor neurons but utilizes extracellular glycerophosphodiester phosphodiesterase activity to induce motor neuron generation by inhibiting Notch signaling in neighboring motor neuron progenitors. Thus, neuronal GDE2 controls motor neuron subtype diversity through a non-cell-autonomous feedback mechanism that directly regulates progenitor cell differentiation, implying that subtype specification initiates within motor neuron progenitor populations prior to their differentiation into postmitotic motor neurons. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Total glucosides of peony attenuates experimental autoimmune encephalomyelitis in C57BL/6 mice.

    Science.gov (United States)

    Huang, Qiling; Ma, Xiaomeng; Zhu, Dong Liang; Chen, Li; Jiang, Ying; Zhou, Linli; Cen, Lei; Pi, Rongbiao; Chen, Xiaohong

    2015-07-15

    Total glucosides of peony (TGP), an active compound extracted from the roots of Paeonia lactiflora Pall, has wide pharmacological effects on nervous system. Here we examined the effects of TGP on experimental autoimmune encephalomyelitis (EAE), an established model of multiple sclerosis (MS). The results showed that TGP can reduce the severity and progression of EAE in C57 BL/6 mice. In addition, TGP also down-regulated the Th1/Th17 inflammatory response and prevented the reduced expression of brain-derived neurotrophic factor and 2',3'-cyclic nucleotide 3'-phosphodiesterase of EAE. These findings suggest that TGP could be a potential therapeutic agent for MS. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Diverse Regulation of Temperature Sensation by Trimeric G-Protein Signaling in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Tomoyo Ujisawa

    Full Text Available Temperature sensation by the nervous system is essential for life and proliferation of animals. The molecular-physiological mechanisms underlying temperature signaling have not been fully elucidated. We show here that diverse regulatory machinery underlies temperature sensation through trimeric G-protein signaling in the nematode Caenorhabditis elegans. Molecular-genetic studies demonstrated that cold tolerance is regulated by additive functions of three Gα proteins in a temperature-sensing neuron, ASJ, which is also known to be a light-sensing neuron. Optical recording of calcium concentration in ASJ upon temperature-changes demonstrated that three Gα proteins act in different aspects of temperature signaling. Calcium concentration changes in ASJ upon temperature change were unexpectedly decreased in a mutant defective in phosphodiesterase, which is well known as a negative regulator of calcium increase. Together, these data demonstrate commonalities and differences in the molecular components concerned with light and temperature signaling in a single sensory neuron.

  16. Diverse Regulation of Temperature Sensation by Trimeric G-Protein Signaling in Caenorhabditis elegans

    Science.gov (United States)

    Ujisawa, Tomoyo; Ohta, Akane; Uda-Yagi, Misato

    2016-01-01

    Temperature sensation by the nervous system is essential for life and proliferation of animals. The molecular-physiological mechanisms underlying temperature signaling have not been fully elucidated. We show here that diverse regulatory machinery underlies temperature sensation through trimeric G-protein signaling in the nematode Caenorhabditis elegans. Molecular-genetic studies demonstrated that cold tolerance is regulated by additive functions of three Gα proteins in a temperature-sensing neuron, ASJ, which is also known to be a light-sensing neuron. Optical recording of calcium concentration in ASJ upon temperature-changes demonstrated that three Gα proteins act in different aspects of temperature signaling. Calcium concentration changes in ASJ upon temperature change were unexpectedly decreased in a mutant defective in phosphodiesterase, which is well known as a negative regulator of calcium increase. Together, these data demonstrate commonalities and differences in the molecular components concerned with light and temperature signaling in a single sensory neuron. PMID:27788246

  17. Turning Failure into Success: Trials of the Heart Failure Clinical Research Network.

    Science.gov (United States)

    Joyce, Emer; Givertz, Michael M

    2016-12-01

    The Heart Failure Clinical Research Network (HFN) was established in 2008 on behalf of the NIH National Heart, Lung and Blood Institute, with the primary goal of improving outcomes in heart failure (HF) by designing and conducting high-quality concurrent clinical trials testing interventions across the spectrum of HF. Completed HFN trials have answered several important and relevant clinical questions concerning the safety and efficacy of different decongestive and adjunctive vasodilator therapies in hospitalized acute HF, phosphodiesterase-5 inhibition and nitrate therapies in HF with preserved ejection fraction, and the role of xanthine oxidase inhibition in hyperuricemic HF. These successes, independent of the "positive" or "negative" result of each individual trial, have helped to shape the current clinical care of HF patients and serve as a platform to inform future research directions and trial designs.

  18. Clearance of Pseudomonas aeruginosa Foreign-Body Biofilm Infections through Reduction of the Cyclic Di-GMP Level in the Bacteria

    DEFF Research Database (Denmark)

    Christensen, Louise D.; van Gennip, Maria; Rybtke, Morten Theil

    2013-01-01

    Opportunistic pathogenic bacteria can engage in biofilm-based infections that evade immune responses and develop into chronic conditions. Because conventional antimicrobials cannot efficiently eradicate biofilms, there is an urgent need to develop alternative measures to combat biofilm infections....... It has recently been established that the secondary messenger cyclic diguanosine monophosphate (c-di-GMP) functions as a positive regulator of biofilm formation in several different bacteria. In the present study we investigated whether manipulation of the c-di-GMP level in bacteria potentially can...... be used for biofilm control in vivo. We constructed a Pseudomonas aeruginosa strain in which a reduction in the c-di-GMP level can be achieved via induction of the Escherichia coli YhjH c-di-GMP phosphodiesterase. Initial experiments showed that induction of yhjH expression led to dispersal...

  19. Early Developmental Program Shapes Colony Morphology in Bacteria

    Directory of Open Access Journals (Sweden)

    Gideon Mamou

    2016-03-01

    Full Text Available When grown on a solid surface, bacteria form highly organized colonies, yet little is known about the earliest stages of colony establishment. Following Bacillus subtilis colony development from a single progenitor cell, a sequence of highly ordered spatiotemporal events was revealed. Colony was initiated by the formation of leading-cell chains, deriving from the colony center and extending in multiple directions, typically in a “Y-shaped” structure. By eradicating particular cells during these early stages, we could influence the shape of the resulting colony and demonstrate that Y-arm extension defines colony size. A mutant in ymdB encoding a phosphodiesterase displayed unordered developmental patterns, indicating a role in guiding these initial events. Finally, we provide evidence that intercellular nanotubes contribute to proper colony formation. In summary, we reveal a “construction plan” for building a colony and provide the initial molecular basis for this process.

  20. Low-energy Shock Wave Therapy-A Novel Treatment Option for Erectile Dysfunction in Men With Cardiovascular Disease.

    Science.gov (United States)

    Kałka, Dariusz; Gebala, Jana; Smoliński, Ryszard; Rusiecki, Lesław; Pilecki, Witold; Zdrojowy, Romuald

    2017-11-01

    Patients with cardiovascular disease (CVD) are prone to developing erectile dysfunction (ED) owing to the common risk factors and pathogenesis underlying ED and CVD. As a result, ED affects nearly 80% of male patients with CVD. The efficacy of phosphodiesterase type 5 inhibitors, vacuum erection devices, or intracavernosal injection of vasodilating agents is well established in the treatment of ED; however, their use is limited. Low-energy shock wave therapy is a novel modality that may become a causative treatment for ED. This review aims to assess the efficacy and safety of low-energy shock wave therapy in the treatment of ED in men with CVD. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Lipid mobilization in subcutaneous adipose tissue during exercise in lean and obese humans. Roles of insulin and natriuretic peptides

    DEFF Research Database (Denmark)

    Koppo, Katrien; Larrouy, Dominique; Marques, Marie A

    2010-01-01

    The aim of this study was to evaluate the relative contributions of various hormones involved in the regulation of lipid mobilization in subcutaneous adipose tissue (SCAT) during exercise and to assess the impact of obesity on this regulation. Eight lean and eight obese men performed a 60-min cycle...... phentolamine and propranolol while another probe was perfused with the phosphodiesterase and adenosine receptor inhibitor aminophylline. Compared with the control condition, infusion of octreotide reduced plasma insulin levels in lean (from approximately 3.5 to 0.5 microU/ml) and in obese (from approximately 9...... to 2 microU/ml), blunted the exercise-induced rise in plasma GH and epinephrine levels in both groups, and enhanced the exercise-induced natriuretic peptide (NP) levels in lean but not in obese subjects. In both groups, octreotide infusion resulted in higher exercise-induced increases in dialysate...

  2. Effect of the caffeine on treated and non-treated plasmid DNA with stannic chloride

    International Nuclear Information System (INIS)

    Moreno, Silvana Ramos F.; Universidade Federal Fluminense, Niteroi, RJ; Mattos, Jose C.P. de; Dantas, Flavio; Araujo, Adriano Caldeira de; Bernardo-Filho, Mario

    2000-01-01

    Caffeine, a methilxantine drug is a component of coffee, tea, stimulants and other drinks. Caffeine inhibits phosphodiesterase leading to intracellular accumulation of cyclic AMP, blocks adenosine receptors, and increases the release of Ca 2+ . We have studied the possible effect of caffeine in DNA plasmid treated or not with stannous chloride (SnCl 2 ). Previous evaluations of the effect of caffeine on the labeling of red blood cells and plasma proteins with technetium-99m have showed a decrease of % ATI in the insoluble fraction of plasma proteins. Samples of DNA were treated with SnCl 2 (0 and 200μg/ml) in 0.8% agarose. SnCl 2 has induced break on DNA and caffeine has not showed effect on the DNA. This indicates that caffeine does not eliminate the oxidant action of SnCl 2 and does not promote break in isolated DNA plasmid. (author)

  3. Effect of sildenafil on gastric emptying and postprandial frequency of antral contractions in healthy humans

    DEFF Research Database (Denmark)

    Madsen, J L; Søndergaard, S B; Fuglsang, S

    2004-01-01

    BACKGROUND: Sildenafil is known to block phosphodiesterase type 5, which degrades nitric oxide-stimulated cyclic guanosine monophosphate, thereby relaxing smooth muscle cells in various organs. The effect of sildenafil on gastric motor function after a meal was investigated in healthy humans....... METHODS: Ten healthy male volunteers (21-28 years) participated in a placebo-controlled, double-blind, cross-over study. In random order and on two separate days each volunteer ingested either 50 mg sildenafil (Viagra, Pfizer, New York, N.Y., USA) or placebo. A gamma camera technique was used to measure......: A single dose of 50 mg sildenafil does not change gastric emptying or postprandial frequency of antral contractions in healthy volunteers....

  4. Dipyridamole may induce migraine in patients with migraine without aura

    DEFF Research Database (Denmark)

    Kruuse, C; Lassen, L H; Iversen, Helle Klingenberg

    2006-01-01

    Dipyridamole inhibits phosphodiesterase 5 (PDE5) and adenosine re-uptake. The most prominent side-effect is headache. We examined the migraine-generating effects of dipyridamole as well as the cerebral blood velocity response in a single-blind study, including 10 patients with migraine without aura...... repeatedly. Headache was induced in all migraine patients and in eight of 10 healthy subjects (P = 0.47) with no significant difference in headache intensity (P = 0.53). However, five patients but only one healthy subject experienced the symptoms of migraine without aura, according to ICHD-2 criteria, within....... Thus, dipyridamole induces symptoms of migraine and an initial decrease in V(mca) in migraine patients, but not significantly more than in healthy subjects. This relatively low frequency of migraine induction, compared with nitric oxide donors and sildenafil, is probably due to the less specific action...

  5. Fragment-based screening by protein crystallography: successes and pitfalls.

    Science.gov (United States)

    Chilingaryan, Zorik; Yin, Zhou; Oakley, Aaron J

    2012-10-08

    Fragment-based drug discovery (FBDD) concerns the screening of low-molecular weight compounds against macromolecular targets of clinical relevance. These compounds act as starting points for the development of drugs. FBDD has evolved and grown in popularity over the past 15 years. In this paper, the rationale and technology behind the use of X-ray crystallography in fragment based screening (FBS) will be described, including fragment library design and use of synchrotron radiation and robotics for high-throughput X-ray data collection. Some recent uses of crystallography in FBS will be described in detail, including interrogation of the drug targets β-secretase, phenylethanolamine N-methyltransferase, phosphodiesterase 4A and Hsp90. These examples provide illustrations of projects where crystallography is straightforward or difficult, and where other screening methods can help overcome the limitations of crystallography necessitated by diffraction quality.

  6. Fragment-Based Discovery of Pyrimido[1,2-b]indazole PDE10A Inhibitors.

    Science.gov (United States)

    Chino, Ayaka; Seo, Ryushi; Amano, Yasushi; Namatame, Ichiji; Hamaguchi, Wataru; Honbou, Kazuya; Mihara, Takuma; Yamazaki, Mayako; Tomishima, Masaki; Masuda, Naoyuki

    2018-01-01

    In this study, we report the identification of potent pyrimidoindazoles as phosphodiesterase10A (PDE10A) inhibitors by using the method of fragment-based drug discovery (FBDD). The pyrazolopyridine derivative 2 was found to be a fragment hit compound which could occupy a part of the binding site of PDE10A enzyme by using the method of the X-ray co-crystal structure analysis. On the basis of the crystal structure of compound 2 and PDE10A protein, a number of compounds were synthesized and evaluated, by means of structure-activity relationship (SAR) studies, which culminated in the discovery of a novel pyrimidoindazole derivative 13 having good physicochemical properties.

  7. Fragment-Based Screening by Protein Crystallography: Successes and Pitfalls

    Directory of Open Access Journals (Sweden)

    Aaron J. Oakley

    2012-10-01

    Full Text Available Fragment-based drug discovery (FBDD concerns the screening of low-molecular weight compounds against macromolecular targets of clinical relevance. These compounds act as starting points for the development of drugs. FBDD has evolved and grown in popularity over the past 15 years. In this paper, the rationale and technology behind the use of X-ray crystallography in fragment based screening (FBS will be described, including fragment library design and use of synchrotron radiation and robotics for high-throughput X-ray data collection. Some recent uses of crystallography in FBS will be described in detail, including interrogation of the drug targets β-secretase, phenylethanolamine N-methyltransferase, phosphodiesterase 4A and Hsp90. These examples provide illustrations of projects where crystallography is straightforward or difficult, and where other screening methods can help overcome the limitations of crystallography necessitated by diffraction quality.

  8. Relaxation of soman-induced contracture of airway smooth muscle in vitro. (Reannouncement with new availability information)

    Energy Technology Data Exchange (ETDEWEB)

    Filbert, M.G.; Moore, D.H.; Adler, M.

    1992-12-31

    A possible role for beta-adrenergic agonists in the management of bronchoconstriction resulting from exposure to anticholinesterase compounds was investigated in vitro in canine tracheal smooth muscle. Norepinephrine, salbutamol and isoproterenol produced partial relaxation of soman-induced contractures. However, the relaxation induced was not sustained; muscle tensions returned to pretreatment levels within minutes despite the continued presence of beta-agonists. Increasing cAMP levels with the non beta-agonist bronchodilators such as thoophylline, a phosphodiesterase inhibitor, or forskolin, a specific stimulator of adenylate cyclase, resulted in more complete and longer lasting relaxation, suggesting that beta-adrenoceptor desensitization may contribute to the failure by beta-agonists to produce sustained relaxation. Nerve agents, Soman, Toxicity, Airway smooth muscle, In vitro, Physiology, Effects.

  9. Potentiation of cGMP signaling increases oxygen delivery and oxidative metabolism in contracting skeletal muscle of older but not young humans

    DEFF Research Database (Denmark)

    Nyberg, Michael Permin; Piil, Peter Bergmann; Egelund, Jon

    2015-01-01

    regulation remain unresolved. Cyclic guanosine monophosphate (cGMP) is one of the main second messengers that mediate smooth muscle vasodilation and alterations in cGMP signaling could, therefore, be one mechanism by which skeletal muscle perfusion is impaired with advancing age. The current study aimed...... to evaluate the effect of inhibiting the main enzyme involved in cGMP degradation, phosphodiesterase 5 (PDE5), on blood flow and O2 delivery in contracting skeletal muscle of young and older humans. A group of young (23 ± 1 years) and a group of older (72 ± 2 years) male human subjects performed submaximal...... in the older subjects correlated with the increase in leg O2 uptake (r (2) = 0.843). These findings suggest an insufficient O2 delivery to the contracting skeletal muscle of aged individuals and that reduced cGMP availability is a novel mechanism underlying impaired skeletal muscle perfusion with advancing age....

  10. Exercise training improves blood flow to contracting skeletal muscle of older men via enhanced cGMP signaling

    DEFF Research Database (Denmark)

    Piil, Peter Bergmann; Smith Jørgensen, Tue; Egelund, Jon

    2018-01-01

    Physical activity has the potential to offset age-related impairments in the regulation of blood flow and O2 delivery to the exercising muscles; however, the mechanisms underlying this effect of physical activity remain poorly understood. The present study examined the role of cGMP in training...... a period of aerobic high-intensity exercise training. To determine the role of cGMP signaling, pharmacological inhibition of phosphodiesterase 5 (PDE5) was performed. Before training, inhibition of PDE5 increased (P... group; however, these effects of PDE5 inhibition were not detected after training. These findings suggest a role for enhanced cGMP signaling in the training-induced improvement of regulation of blood flow in contracting skeletal muscle of older men....

  11. A comparison of the inhibitory activity of selective PDE4 inhibitors on eosinophil recruitment in guinea pig skin

    Directory of Open Access Journals (Sweden)

    Mauro M Teixeira

    1997-12-01

    Full Text Available The elevation of intracellular cyclic AMP by phosphodiesterase (PDE4 inhibitors in eosinophils is associated with inhibition of the activation and recruitment of these cells. We have previously shown that systemic treatment with the PDE4 inhibitor rolipram effectively inhibt eosinophil migration in guinea pig skin. In the present study we compare the oral potency and efficacy of the PDE4 inhibitors rolipram, RP 73401 and CDP 840 on allergic and PAF-induced eosinophil recruitment. Rolipram and RP 73401 were equally effective and potent when given by the oral route and much more active than the PDE4 inhibitor CDP 840. We suggest that this guinea pig model of allergic and mediator-induced eosinophil recruitment is both a sensitive and simple tool to test the efficacy and potency of PDE4 inhibitors in vivo.

  12. Antidepressant effects of total tertiary alkaloid fraction of Cissampelos sympodialis Eichler in rodents

    Directory of Open Access Journals (Sweden)

    Sueli Mendonça-Netto

    Full Text Available The purpose of the present study was to evaluate the effects of total tertiary alkaloid fraction (TTAF of Cissampelos sympodialis Eichler (Menispermaceae on two animal models of depression: a forced swim test and b reserpine test. Treatment of mice with TTAF (12.5 mg/kg reduced the total immobility time. It also reversed the reserpine-induced hypothermia, demonstrating an antidepressant effect in both models. Additionally, TTAF treatment did not modify the ambulation and rearing evaluated in open field test in order to investigate if the immobility time reduction found in the forced swimming test was caused by locomotive activity stimulation. Since warifteine is one of the main alkaloids present in the TTAF of C. sympodialis, and it has inhibitory activity of the phosphodiesterase enzyme, it may be responsible by the antidepressant effect found in the fraction studied.

  13. Challenges in sexual medicine

    DEFF Research Database (Denmark)

    Cellek, Selim; Giraldi, Annamaria

    2012-01-01

    The sexual medicine field has been in mode of revolution until recently. Like all other fields of biomedical research, the economic situation around the world has had a negative impact on the field's momentum-research funding bodies, regulatory bodies and pharmaceutical companies seem to have...... placed sexual medicine in their low-priority list. But this is not the only challenge the field is facing. The successful development of phosphodiesterase type 5 (PDE5) inhibitors for treatment of erectile dysfunction (ED) means that research in this area seems to have slowed. However, there remain...... several unmet medical needs within sexual medicine such as premature ejaculation, severe ED and hypoactive sexual desire disorder, which await novel therapeutic approaches. Despite these challenges, research into finding and developing such therapies is likely to continue in the sexual medicine field...

  14. Palmoplantar Psoriasis and Palmoplantar Pustulosis: Current Treatment and Future Prospects.

    Science.gov (United States)

    Raposo, Inês; Torres, Tiago

    2016-08-01

    Palmoplantar psoriasis and palmoplantar pustulosis are chronic skin diseases with a large impact on patient quality of life. They are frequently refractory to treatment, being generally described as a therapeutic challenge. This article aims to review the definitions of palmoplantar psoriasis and palmoplantar pustulosis, highlighting the similarities and differences in terms of epidemiology, clinical presentation, genetics, histopathology, and pathogenesis, as well as treatment options for both entities. Classical management of mild to moderate palmoplantar pustulosis and palmoplantar psoriasis relies on use of potent topical corticosteroids, phototherapy, and/or acitretin. Nevertheless, these drugs have proven to be insufficient in long-term control of extensive disease. Biologic therapy-namely, anti-interleukin-17 agents and phosphodiesterase type 4 inhibitors-has recently shown promising results in the treatment of palmoplantar psoriasis. Knowledge of the pathophysiologic pathways of both entities is of utmost importance and may, in the future, allow development of molecularly targeted therapeutics.

  15. Effects of drugs on platelet function.

    Science.gov (United States)

    Morse, E E

    1977-01-01

    Numerous drugs and chemicals affect the function of human blood platelets. The mechanism of action of some medications is partly understood. Aspirin is the most frequently involved drug. It appears to interfere with the platelet release reaction by acetylation of a platelet membrane protein which may be involved in the synthesis of prostaglandins. Other anti-inflammatory drugs, including indomethacin, phenylbutazone, ibuprophen (Motrin) and clonixin, also interfere with the release reaction but have a shorter acting course than aspirin. Some drugs stimulate adenylcyclase (gliclazide) or block phosphodiesterase, (dipyridamole, caffeine) both of which actions lead to an increase in adenosine cyclic 3':5' monophosphate (cAMP) and decrease aggregation by adenosine diphosphate (ADP). These interactions should be known to clinical scientists since patients using these medicaments may manifest abnormal platelet function tests in the laboratory and mild hemorrhagic syndromes in the clinic.

  16. Synthesis and characterization of polymeric hydrogel containing caffeine for cosmeceutical applications

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Tiago C.; Oliveira, Maria José A.; Lugão, Ademar B., E-mail: tiagocesar-13@hotmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNE-SP), Sao Paulo, SP (Brazil)

    2017-07-01

    Caffeine, a substance with belongs to the group of methylxanthines, is alkaloids that penetrate in the human epidermis but is not easily absorbed into the bloodstream. With a dermatological active substance, it exerts action on the subcutaneous adipose tissue causing adipocyte lipolysis through the inhibition of phosphodiesterase. Based on these considerations, the objective of this study was to investigate the behavior of caffeine in a polymeric hydrogel matrix, for possible cosmeceutical applications. The hydrogels were cross-linked and sterilized by Cobalt-60 source gamma irradiation. In the characterization, were used thermogravimetry (TGA), scanning electron microscopy (SEM), differential scanning calorimetry (DSC). It was possible to observe by SEM the presence of crystals in the hydrogel sample. The DSC experiment confirmed a crystallinity of the sample and that caffeine is not degraded by gamma irradiation at 25 kGy. The results were satisfactory, allowing a new investigations that certify the benefits of its application. (author)

  17. Automated enzymatic measurement of lecithin, sphingomyelin, and phosphatidylglycerol in amniotic fluid.

    Science.gov (United States)

    Bradley, C A; Salhany, K E; Entman, S S; Aleshire, S L; Parl, F F

    1987-01-01

    We describe methods for automated enzymatic measurement of lecithin, sphingomyelin, and phosphatidylglycerol in amniotic fluid. Phospholipase C (EC 3.1.4.3) and sphingomyelin phosphodiesterase (EC 3.1.4.12) are reacted with lecithin and sphingomyelin, respectively, to liberate phosphocholine. Phosphocholine is then reacted with alkaline phosphatase, choline oxidase, peroxidase, and 4-aminoantipyrine to form a colored complex, for which the absorbance at 500 nm is measured with a centrifugal analyzer. Phosphatidylglycerol is hydrolyzed by phospholipase D (EC 3.1.4.4) to form glycerol, which is subsequently reacted with ATP and NAD+ in the presence of glycerol kinase and glycerol-3-phosphate dehydrogenase to yield NADH. The absorbance of the NADH formed is measured at 340 nm. These methods provide a simple, rapid, and accurate alternative to thin-layer chromatography for determination of phospholipids in amniotic fluid for assessment of fetal lung maturity.

  18. A high-performance liquid chromatography-based radiometric assay for sucrose-phosphate synthase and other UDP-glucose requiring enzymes

    International Nuclear Information System (INIS)

    Salvucci, M.E.; Crafts-Brandner, S.J.

    1991-01-01

    A method for product analysis that eliminates a problematic step in the radiometric sucrose-phosphate synthase assay is described. The method uses chromatography on a boronate-derivatized high-performance liquid chromatography column to separate the labeled product, [14C]sucrose phosphate, from unreacted uridine 5'-diphosphate-[14C]glucose (UDP-Glc). Direct separation of these compounds eliminates the need for treatment of the reaction mixtures with alkaline phosphatase, thereby avoiding the problem of high background caused by contaminating phosphodiesterase activity in alkaline phosphatase preparations. The method presented in this paper can be applied to many UDP-Glc requiring enzymes; here the authors show its use for determining the activities of sucrose-phosphate synthase, sucrose synthase, and uridine diphosphate-glucose pyrophosphorylase in plant extracts

  19. Association study of PDE4B gene variants in Scandinavian schizophrenia and bipolar disorder multicenter case-control samples

    DEFF Research Database (Denmark)

    Kähler, Anna K; Otnæss, Mona K; Wirgenes, Katrine V

    2010-01-01

    The phosphodiesterase 4B (PDE4B), which is involved in cognitive function in animal models, is a candidate susceptibility gene for schizophrenia (SZ) and bipolar disorder (BP). Variations in PDE4B have previously been associated with SZ, with a suggested gender-specific effect. We have genotyped......SNPs were nominally associated (0.0005 gender-specific subgroups. None of these findings remained significant after correction for multiple testing. However, a number of tagSNPs found to be nominally associated with SZ and BP...... were located in a high LD region spanning the splice site of PDE4B3, an isoform with altered brain expression in BP patients. Four tagSNPs were associated with SZ in women, but none in men, in agreement with the previously reported gender-specific effect. Proxies of two nominally associated SNPs...

  20. Decreased catalytic activity and altered activation properties of PDE6C mutants associated with autosomal recessive achromatopsia

    DEFF Research Database (Denmark)

    Grau, Tanja; Artemyev, Nikolai O; Rosenberg, Thomas

    2011-01-01

    study on PDE6C mutations including the mutation spectrum, its prevalence in a large cohort of ACHM/cone dysfunction patients, the clinical phenotype and the functional characterization of mutant PDE6C proteins. Twelve affected patients from seven independent families segregating PDE6C mutations were......Mutations in the gene encoding the catalytic subunit of the cone photoreceptor phosphodiesterase (PDE6C) have been recently reported in patients with autosomal recessive inherited achromatopsia (ACHM) and early-onset cone photoreceptor dysfunction. Here we present the results of a comprehensive...... identified in our total patient cohort of 492 independent families. Eleven different PDE6C mutations were found including two nonsense mutations, three mutations affecting transcript splicing as shown by minigene assays, one 1 bp-insertion and five missense mutations. We also performed a detailed functional...

  1. mc1r Pathway regulation of zebrafish melanosome dispersion

    DEFF Research Database (Denmark)

    Richardson, Jennifer; Lundegaard, Pia Rengtved; Reynolds, Natalie L

    2008-01-01

    Zebrafish rapidly alter their pigmentation in response to environmental changes. For black melanocytes, this change is due to aggregation or dispersion of melanin in the cell. Dispersion and aggregation are controlled by intracellular cyclic adenosine monophosphate (cAMP) levels, which increase...... in mammals, and melanosome dispersal in cold-blood vertebrates, the pathway components are highly conserved. However, it has only been assumed that mc1r mediates melanosome dispersal in fish. Here, using morpholino oligonucleotides designed to knockdown mc1r expression, we find that mc1r morphants are unable...... to disperse melanosomes when grown in dark conditions. We also use chemical modifiers of the cAMP pathway, and find an unexpected response to the specific phosphodiesterase 4 (PDE4) inhibitor, rolipram, in melanosome dispersal. When treated with the drug, melanosomes fail to fully disperse in dark conditions...

  2. Roflumilast: clinical benefit in patients suffering from COPD

    DEFF Research Database (Denmark)

    Ulrik, Charlotte Suppli; Calverley, Peter Michael Anthony

    2010-01-01

    BACKGROUND AND AIMS: Chronic obstructive pulmonary disease (COPD) is associated with substantial morbidity and mortality and is characterised by persistent airway inflammation, which leads to impaired airway function, quality of life and intermittent exacerbations. In spite of recent advances...... in the treatment of COPD, new treatment options for COPD are clearly necessary. The oral phosphodiesterase-4 (PDE4) inhibitor roflumilast represents a new class of drugs that has shown efficacy and acceptable tolerability in preclinical and short-term clinical studies in patients with COPD. METHODS AND RESULTS......) , and a reduction in frequency and severity of COPD exacerbations, as well as a positive effect on several patient-reported outcomes. The clinical benefit of roflumilast appears to be greatest in patients with more symptomatic and severe disease who experience exacerbations. The most common adverse effects...

  3. Roflumilast: clinical benefit in patients suffering from COPD

    DEFF Research Database (Denmark)

    Ulrik, Charlotte Suppli; Calverley, Peter Michael Anthony

    2010-01-01

    BACKGROUND AND AIMS:  Chronic obstructive pulmonary disease (COPD) is associated with substantial morbidity and mortality and is characterised by persistent airway inflammation, which leads to impaired airway function, quality of life and intermittent exacerbations. In spite of recent advances...... in the treatment of COPD, new treatment options for COPD are clearly necessary. The oral phosphodiesterase-4 (PDE4) inhibitor roflumilast represents a new class of drugs that has shown efficacy and acceptable tolerability in preclinical and short-term clinical studies in patients with COPD. METHODS AND RESULTS......) , and a reduction in frequency and severity of COPD exacerbations, as well as a positive effect on several patient-reported outcomes. The clinical benefit of roflumilast appears to be greatest in patients with more symptomatic and severe disease who experience exacerbations. The most common adverse effects...

  4. Chloride transport in toad skin (Bufo viridis). The effect of salt adaptation

    DEFF Research Database (Denmark)

    Katz, U; Larsen, Erik Hviid

    1984-01-01

    The steady-state Cl- current across the skin of Bufo viridis adapted to tap water was found to be rectified. In skins bathed with NaCl Ringer on both sides, a large outward current, carried by influx of Cl-, was observed at a clamping voltage (V) of less than -50 mV (outside of the skin negative......, and apparent leakage conductance was reduced. Application of the phosphodiesterase inhibitor 3-isobutyl-1-methyl-xanthine to skin of fully salt-adapted toads increased the transepithelial Cl- conductance, and the time courses of voltage clamp currents became more like those of water-adapted toads. Apparent...... leakage conductance was increased.(ABSTRACT TRUNCATED AT 400 WORDS)...

  5. Crystal structure of an apremilast ethanol hemisolvate hemihydrate solvatomorph

    Directory of Open Access Journals (Sweden)

    Yun-Deng Wu

    2017-06-01

    Full Text Available The title compound, C22H24N2O7S·0.5C2H5OH·0.5H2O {systematic name: (S-4-acetamido-2-[1-(3-ethoxy-4-methoxyphenyl-2-(methylsulfonylethyl]isoindoline-1,3-dione ethanol hemisolvate hemihydrate}, is a novel solvatomorph of apremilast (AP, which is an inhibitor of phosphodiesterase 4 (PDE4 and is indicated for the treatment of adult patients with active psoriatic arthritis. The asymmetric unit contains one molecule of AP and disordered molecules of ethanol and water, both with half occupancy. The dihedral angle between the planes of the phenyl ring and the isoindole ring is 67.9 (2°. Extensive intra- and intermolecular hydrogen bonds help to stabilize the molecular conformation and sustain the crystal packing.

  6. Lipopolysaccharide-induced acute renal failure in conscious rats

    DEFF Research Database (Denmark)

    Jonassen, Thomas E N; Graebe, Martin; Promeneur, Dominique

    2002-01-01

    In conscious, chronically instrumented rats we examined 1) renal tubular functional changes involved in lipopolysaccharide (LPS)-induced acute renal failure; 2) the effects of LPS on the expression of selected renal tubular water and sodium transporters; and 3) effects of milrinone......-alpha and lactate, inhibited the LPS-induced tachycardia, and exacerbated the acute LPS-induced fall in GFR. Furthermore, Ro-20-1724-treated rats were unable to maintain MAP. We conclude 1) PDE3 or PDE4 inhibition exacerbates LPS-induced renal failure in conscious rats; and 2) LPS treated rats develop an escape......, a phosphodiesterase type 3 (PDE3) inhibitor, and Ro-20-1724, a PDE4 inhibitor, on LPS-induced changes in renal function. Intravenous infusion of LPS (4 mg/kg b.wt. over 1 h) caused an immediate decrease in glomerular filtration rate (GFR) and proximal tubular outflow without changes in mean arterial pressure (MAP...

  7. Compartmentalization of NO signaling cascade in skeletal muscles

    International Nuclear Information System (INIS)

    Buchwalow, Igor B.; Minin, Evgeny A.; Samoilova, Vera E.; Boecker, Werner; Wellner, Maren; Schmitz, Wilhelm; Neumann, Joachim; Punkt, Karla

    2005-01-01

    Skeletal muscle functions regulated by NO are now firmly established. However, the literature on the compartmentalization of NO signaling in myocytes is highly controversial. To address this issue, we examined localization of enzymes engaged in L-arginine-NO-cGMP signaling in the rat quadriceps muscle. Employing immunocytochemical labeling complemented with tyramide signal amplification and electron microscopy, we found NO synthase expressed not only in the sarcolemma, but also along contractile fibers, in the sarcoplasmic reticulum and mitochondria. The expression pattern of NO synthase in myocytes showed striking parallels with the enzymes engaged in L-arginine-NO-cGMP signaling (arginase, phosphodiesterase, and soluble guanylyl cyclase). Our findings are indicative of an autocrine fashion of NO signaling in skeletal muscles at both cellular and subcellular levels, and challenge the notion that the NO generation is restricted to the sarcolemma

  8. Silencing the alarms: innate immune antagonism by rotavirus NSP1 and VP3

    Science.gov (United States)

    Morelli, Marco; Ogden, Kristen M.; Patton, John T.

    2016-01-01

    The innate immune response involves a broad array of pathogen sensors that stimulate the production of interferons (IFN) to induce an antiviral state. Rotavirus, a significant cause of childhood gastroenteritis and a member of the Reoviridae family of segmented, double-stranded RNA viruses, encodes at least two direct antagonists of host innate immunity: NSP1 and VP3. NSP1, a putative E3 ubiquitin ligase, mediates the degradation of cellular factors involved in both IFN induction and downstream signaling. VP3, the viral capping enzyme, utilizes a 2H-phosphodiesterase domain to prevent activation of the cellular oligoadenylate synthase (OAS)-RNase L pathway. Computational, molecular, and biochemical studies have provided key insights into the structural and mechanistic basis of innate immune antagonism by NSP1 and VP3 of group A rotaviruses (RVA). Future studies with non-RVA isolates will be essential to understand how other RV species evade host innate immune responses. PMID:25724417

  9. Pulmonary Arterial Hypertension in Adults: Novel Drugs and Catheter Ablation Techniques Show Promise? Systematic Review on Pharmacotherapy and Interventional Strategies

    Directory of Open Access Journals (Sweden)

    Salvatore Rosanio

    2014-01-01

    Full Text Available This systematic review aims to provide an update on pharmacological and interventional strategies for the treatment of pulmonary arterial hypertension in adults. Currently US Food and Drug Administration approved drugs including prostanoids, endothelin-receptor antagonists, phosphodiesterase type-5 inhibitors, and soluble guanylate-cyclase stimulators. These agents have transformed the prognosis for pulmonary arterial hypertension patients from symptomatic improvements in exercise tolerance ten years ago to delayed disease progression today. On the other hand, percutaneous balloon atrioseptostomy by using radiofrequency perforation, cutting balloon dilatation, or insertion of butterfly stents and pulmonary artery catheter-based denervation, both associated with very low rate of major complications and death, should be considered in combination with specific drugs at an earlier stage rather than late in the progression of pulmonary arterial hypertension and before the occurrence of overt right-sided heart failure.

  10. Immunochemical similarity of GTP-binding proteins from different systems

    International Nuclear Information System (INIS)

    Kalinina, S.N.

    1986-01-01

    It was found that antibodies against the GTP-binding proteins of bovine retinal photoreceptor membranes blocked the inhibitory effect of estradiol on phosphodiesterase from rat and human uterine cytosol and prevented the cumulative effect of catecholamines and guanylyl-5'-imidodiphosphate on rat skeletal muscle adenylate cyclase. It was established by means of double radial immunodiffusion that these antibodies form a precipitating complex with purified bovine brain tubulin as well as with retinal preparations obtained from eyes of the bull, pig, rat, frog, some species of fish, and one reptile species. Bands of precipitation were not observed with these antibodies when retinal preparations from invertebrates (squid and octopus) were used as the antigens. The antibodies obtained interacted with the α- and β-subunits of GTP-binding proteins from bovine retinal photoreceptor membranes

  11. Zinc Signals and Immunity.

    Science.gov (United States)

    Maywald, Martina; Wessels, Inga; Rink, Lothar

    2017-10-24

    Zinc homeostasis is crucial for an adequate function of the immune system. Zinc deficiency as well as zinc excess result in severe disturbances in immune cell numbers and activities, which can result in increased susceptibility to infections and development of especially inflammatory diseases. This review focuses on the role of zinc in regulating intracellular signaling pathways in innate as well as adaptive immune cells. Main underlying molecular mechanisms and targets affected by altered zinc homeostasis, including kinases, caspases, phosphatases, and phosphodiesterases, will be highlighted in this article. In addition, the interplay of zinc homeostasis and the redox metabolism in affecting intracellular signaling will be emphasized. Key signaling pathways will be described in detail for the different cell types of the immune system. In this, effects of fast zinc flux, taking place within a few seconds to minutes will be distinguish from slower types of zinc signals, also designated as "zinc waves", and late homeostatic zinc signals regarding prolonged changes in intracellular zinc.

  12. Cross-talk between PKA-Cβ and p65 mediates synergistic induction of PDE4B by roflumilast and NTHi

    Science.gov (United States)

    Susuki-Miyata, Seiko; Miyata, Masanori; Lee, Byung-Cheol; Xu, Haidong; Kai, Hirofumi; Yan, Chen; Li, Jian-Dong

    2015-01-01

    Phosphodiesterase 4B (PDE4B) plays a key role in regulating inflammation. Roflumilast, a phosphodiesterase (PDE)4-selective inhibitor, has recently been approved for treating severe chronic obstructive pulmonary disease (COPD) patients with exacerbation. However, there is also clinical evidence suggesting the development of tachyphylaxis or tolerance on repeated dosing of roflumilast and the possible contribution of PDE4B up-regulation, which could be counterproductive for suppressing inflammation. Thus, understanding how PDE4B is up-regulated in the context of the complex pathogenesis and medications of COPD may help improve the efficacy and possibly ameliorate the tolerance of roflumilast. Here we show that roflumilast synergizes with nontypeable Haemophilus influenzae (NTHi), a major bacterial cause of COPD exacerbation, to up-regulate PDE4B2 expression in human airway epithelial cells in vitro and in vivo. Up-regulated PDE4B2 contributes to the induction of certain important chemokines in both enzymatic activity-dependent and activity-independent manners. We also found that protein kinase A catalytic subunit β (PKA-Cβ) and nuclear factor-κB (NF-κB) p65 subunit were required for the synergistic induction of PDE4B2. PKA-Cβ phosphorylates p65 in a cAMP-dependent manner. Moreover, Ser276 of p65 is critical for mediating the PKA-Cβ–induced p65 phosphorylation and the synergistic induction of PDE4B2. Collectively, our data unveil a previously unidentified mechanism underlying synergistic up-regulation of PDE4B2 via a cross-talk between PKA-Cβ and p65 and may help develop new therapeutic strategies to improve the efficacy of PDE4 inhibitor. PMID:25831493

  13. Dendritic diameter influences the rate and magnitude of hippocampal cAMP and PKA transients during β-adrenergic receptor activation.

    Science.gov (United States)

    Luczak, Vincent; Blackwell, Kim T; Abel, Ted; Girault, Jean-Antoine; Gervasi, Nicolas

    2017-02-01

    In the hippocampus, cyclic-adenosine monophosphate (cAMP) and cAMP-dependent protein kinase (PKA) form a critical signaling cascade required for long-lasting synaptic plasticity, learning and memory. Plasticity and memory are known to occur following pathway-specific changes in synaptic strength that are thought to result from spatially and temporally coordinated intracellular signaling events. To better understand how cAMP and PKA dynamically operate within the structural complexity of hippocampal neurons, we used live two-photon imaging and genetically-encoded fluorescent biosensors to monitor cAMP levels or PKA activity in CA1 neurons of acute hippocampal slices. Stimulation of β-adrenergic receptors (isoproterenol) or combined activation of adenylyl cyclase (forskolin) and inhibition of phosphodiesterase (IBMX) produced cAMP transients with greater amplitude and rapid on-rates in intermediate and distal dendrites compared to somata and proximal dendrites. In contrast, isoproterenol produced greater PKA activity in somata and proximal dendrites compared to intermediate and distal dendrites, and the on-rate of PKA activity did not differ between compartments. Computational models show that our observed compartmental difference in cAMP can be reproduced by a uniform distribution of PDE4 and a variable density of adenylyl cyclase that scales with compartment size to compensate for changes in surface to volume ratios. However, reproducing our observed compartmental difference in PKA activity required enrichment of protein phosphatase in small compartments; neither reduced PKA subunits nor increased PKA substrates were sufficient. Together, our imaging and computational results show that compartment diameter interacts with rate-limiting components like adenylyl cyclase, phosphodiesterase and protein phosphatase to shape the spatial and temporal components of cAMP and PKA signaling in CA1 neurons and suggests that small neuronal compartments are most sensitive to c

  14. Chronic fluoxetine treatment increases daytime melatonin synthesis in the rodent

    Directory of Open Access Journals (Sweden)

    Gillian W Reierson

    2009-09-01

    Full Text Available Gillian W Reierson, Claudio A Mastronardi, Julio Licinio, Ma-Li WongCenter on Pharmacogenomics, Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL, USAAbstract: Circadian rhythm disturbances can occur as part of the clinical symptoms of major depressive disorder and have been found to resolve with antidepressant therapy. The pineal gland is relevant to circadian rhythms as it secretes the hormone melatonin following activation of the cyclic adenosine monophosphate (cAMP signaling cascade and of arylalkylamine N-acetyltransferase (AA-NAT, the rate-limiting enzyme for its synthesis. Cyclic AMP is synthesized by adenylate cyclases (AC and degraded by phosphodiesterases (PDEs. Little is known about the contribution of the PDE system to antidepressant-induced alterations in pineal cAMP signaling and melatonin synthesis. In the present study we used enzyme immunoassay to measure plasma melatonin levels and pineal cAMP levels and as well as quantitative real-time polymerase chain reaction to measure pineal expression of PDE, AC, and AA-NAT genes in rats chronically treated with the prototypic antidepressant fluoxetine. We found elevated melatonin synthesis with increased pineal AA-NAT gene expression and daytime plasma melatonin levels and downregulated cAMP signaling with increased PDE and unchanged AC pineal gene expression, and decreased content of pineal cAMP. We conclude that chronic fluoxetine treatment increases daytime plasma melatonin and pineal AA-NAT gene expression despite downregulated pineal cAMP signaling in the rodent.Keywords: antidepressant, melatonin, pineal, nucleotides, cyclic, phosphodiesterase, rat

  15. U-61,431F, a stable prostacyclin analogue, inhibits the proliferation of bovine vascular smooth muscle cells with little antiproliferative effect on endothelial cells

    International Nuclear Information System (INIS)

    Shirotani, M.; Yui, Y.; Hattori, R.; Kawai, C.

    1991-01-01

    The effects of U-61,431F, ciprostene, a stable prostacyclin analogue, were examined on the proliferation of cultured quiescent bovine aortic endothelial cells (EC) and smooth muscle cells (SMC). After stimulation with 5% fetal calf serum, U-61,431F suppressed both the DNA synthesis and proliferation of SMC dose-dependently at the concentration of 3-100 microM, but had no effect on either of them in EC at a concentration of up to 30 microM. The inhibitory effect on DNA synthesis was greater in SMC than in EC at 3-50 microM. When SMC were stimulated with platelet-derived growth factor (PDGF) for 2 hrs followed by a 22-hr incubation with insulin, U-61,431F (1-50 microM) administered at the time of PDGF stimulation did not inhibit DNA synthesis. SMC initiated and terminated DNA synthesis at about 15-18 h and 24 h after stimulation with serum, respectively. Inhibition of DNA synthesis in serum-stimulated SMC as a function of the addition time of U-61,431F reduced at 3-12 h after the stimulation. U-61,431F raised the cyclic AMP (cAMP) content in SMC. Moreover, a phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine, and a more specific cAMP phosphodiesterase inhibitor, Ro 20-1724, augmented the inhibition of DNA synthesis in SMC concomitant with further elevation of cAMP level. These results suggest that U-61,431F inhibits DNA synthesis of SMC acting in the progression stage rather than in the competence stage, with little antiproliferative effect on EC. cAMP may play an important role in its antiproliferative action in SMC

  16. Tokay gecko photoreceptors achieve rod-like physiology with cone-like proteins.

    Science.gov (United States)

    Zhang, Xue; Wensel, Theodore G; Yuan, Ching

    2006-01-01

    The retinal photoreceptors of the nocturnal Tokay gecko (Gekko gekko) consist exclusively of rods by the criteria of morphology and key features of their light responses. Unlike cones, they display robust photoresponses and have relatively slow recovery times. Nonetheless, the major and minor visual pigments identified in gecko rods are of the cone type by sequence and spectroscopic behavior. In the ongoing search for the molecular bases for the physiological differences between cones and rods, we have characterized the molecular biology and biochemistry of the gecko rod phototransduction cascade. We have cloned cDNAs encoding all or part of major protein components of the phototransduction cascade by RT-PCR with degenerate oligonucleotides designed to amplify cone- or rod-like sequences. For all proteins examined we obtained only cone-like and never rod-like sequences. The proteins identified include transducin alpha (Galphat), phosphodiesterase (PDE6) catalytic and inhibitory subunits, cyclic nucleotide-gated channel (CNGalpha) and arrestin. We also cloned cDNA encoding gecko RGS9-1 (Regulator of G Protein Signaling 9, splice variant 1), which is expressed in both rods and cones of all species studied but is typically found at 10-fold higher concentrations in cones, and found that gecko rods contain slightly lower RGS9-1 levels than mammalian rods. Furthermore, we found that the levels of GTPase accelerating protein (GAP) activity and cyclic GMP (cGMP) phosphodiesterase activity were similar in gecko and mammalian rods. These results place substantial constraints on the critical changes needed to convert a cone into a rod in the course of evolution: The many features of phototransduction molecules conserved between those expressed in gecko rods and those expressed in cones cannot explain the physiological differences, whereas the higher levels of RGS9-1 and GAP activity in cones are likely among the essential requirements for the rapid photoresponses of cones.

  17. Population pharmacokinetics of olprinone in healthy male volunteers

    Directory of Open Access Journals (Sweden)

    Kunisawa T

    2014-03-01

    Full Text Available Takayuki Kunisawa,1 Hidefumi Kasai,2 Makoto Suda,2 Manabu Yoshimura,3 Ami Sugawara,3 Yuki Izumi,3 Takafumi Iida,3 Atsushi Kurosawa,3 Hiroshi Iwasaki3 1Surgical Operation Department, Asahikawa Medical University Hospital, Hokkaido, Japan; 2Clinical Study Management Division, Bell Medical Solutions Inc, Tokyo, Japan; 3Department of Anesthesiology and Critical Care Medicine, Asahikawa Medical University, Hokkaido, Japan Background: Olprinone decreases the cardiac preload and/or afterload because of its vasodilatory effect and increases myocardial contractility by inhibiting phosphodiesterase III. Purpose: The objective of this study was to characterize the population pharmacokinetics of olprinone after a single continuous infusion in healthy male volunteers. Methods: We used 500 plasma concentration data points collected from nine healthy male volunteers for the study. The population pharmacokinetic analysis was performed using the nonlinear mixed effect model (NONMEM® software. Results: The time course of plasma concentration of olprinone was best described using a two-compartment model. The final pharmacokinetic parameters were total clearance (7.37 mL/minute/kg, distribution volume of the central compartment (134 mL/kg, intercompartmental clearance (7.75 mL/minute/kg, and distribution volume of the peripheral compartment (275 mL/kg. The interindividual variability in the total clearance was 12.4%, and the residual error variability (exponential and additive were 22.2% and 0.129 (standard deviation. The final pharmacokinetic model was assessed using a bootstrap method and visual predictive check. Conclusion: We developed a population pharmacokinetic model of olprinone in healthy male adults. The bootstrap method and visual predictive check showed that this model was appropriate. Our results might be used to develop the population pharmacokinetic model in patients. Keywords: phosphodiesterase III inhibitor, men, pharmacokinetic model

  18. The application of color Doppler flow imaging in the diagnosis and therapeutic effect evaluation of erectile dysfunction

    Directory of Open Access Journals (Sweden)

    Xu-Jun Xuan

    2016-01-01

    Full Text Available We aim to investigate the correlations between hemodynamic parameters, penile rigidity grading, and the therapeutic effects of phosphodiesterase type 5 inhibitors using color Doppler flow imaging after intracavernosal injection in patients with erectile dysfunction. This study involved 164 patients. After intracavernosal injection with a mixture of papaverine (60 mg, prostaglandin E 1 (10 mg, and lidocaine (2%, 0.5-1 ml, the penile vessels were assessed using color Doppler flow imaging. Penile rigidity was classified based on the Erection Hardness Score system as Grades 4, 3, 2 or 1 (corresponding to Schramek Grades V to II. Then, the patients were given oral sildenafil (50-100 mg and scored according to the International Index of Erectile Function (IIEF-5 questionnaire. The number of patients with penile rigidities of Schramek Grades II to V was 14, 18, 21, and 111, respectively. The IIEF-5 score was positively correlated with the refilling index of the penile cavernosal artery (r = 0.79, P< 0.05, the peak systolic velocity (r = 0.45, P< 0.05, and penile rigidity (r = 0.75, P< 0.05, and was negatively correlated with the end diastolic velocity (r = −0.74, P< 0.05. For patients with erectile dysfunction, both the IIEF-5 score after sildenafil administration, which is correlated with penile rigidity, and the hemodynamic parameters detected using color Doppler flow imaging may predict the effects of phosphodiesterase type 5 inhibitor treatment and could provide a reasonable model for the targeted-treatment of erectile dysfunction.

  19. Clinical deterioration after sildenafil cessation in patients with pulmonary hypertension

    Directory of Open Access Journals (Sweden)

    Anne M Keogh

    2008-10-01

    Full Text Available Anne M Keogh, Andrew Jabbour, Christopher S Hayward, Peter S MacdonaldHeart Lung Transplant Unit, St Vincent’s Hospital, Sydney, New South Wales, AustraliaAbstract: Sildenafil is a selective inhibitor of phosphodiesterase type 5 (PDE-5. Its chronic administration has been shown to improve exercise capacity, World Health Organization functional class, and haemodynamics in patients with symptomatic pulmonary arterial hypertension (PAH. There is however, no data describing the clinical consequences of sudden cessation of sildenafil treatment. In this series, 9 patients with NYHA Class II–IV PAH who were stable on 2 months of sildenafil monotherapy, had their sildenafil ceased to accommodate a 2-week washout period, required for enrollment in research involving an endothelin receptor antagonist. Six minute walk distance (SMWD and clinical assessments were performed before cessation of sildenafil, and again 2 weeks later. Over the course of this 2-week washout period, 6 of the 9 patients reported increased breathlessness and fatigue, 1 of these was hospitalized with worsening right heart failure. The SMWD fell in 6 patients, with falls of greater than 100 m recorded in 4 patients. This was accompanied by a worsening of NYHA Class from 2.5 ± 0.2 to 3.1 ± 0.1 (mean ± SEM, p = 0.01. These data indicate that sudden cessation of sildenafil monotherapy, in patients with PAH, carries with it a significant and unpredictable risk of rapid clinical deterioration. We recommend that if sildenafil needs to be ceased, it would be more prudent to consider concurrent vasodilator therapy before the gradual cessation of sildenafil.Keywords: sildenafil, pulmonary hypertension, phosphodiesterase inhibitor

  20. Three Antagonistic Cyclic di-GMP-Catabolizing Enzymes Promote Differential Dot/Icm Effector Delivery and Intracellular Survival at the Early Steps of Legionella pneumophila Infection

    Science.gov (United States)

    Allombert, Julie; Lazzaroni, Jean-Claude; Baïlo, Nathalie; Gilbert, Christophe; Charpentier, Xavier; Doublet, Patricia

    2014-01-01

    Legionella pneumophila is an intracellular pathogen which replicates within protozoan cells and can accidently infect alveolar macrophages, causing an acute pneumonia in humans. The second messenger cyclic di-GMP (c-di-GMP) has been shown to play key roles in the regulation of various bacterial processes, including virulence. While investigating the function of the 22 potential c-di-GMP-metabolizing enzymes of the L. pneumophila Lens strain, we found three that directly contribute to its ability to infect both protozoan and mammalian cells. These three enzymes display diguanylate cyclase (Lpl0780), phosphodiesterase (Lpl1118), and bifunctional diguanylate cyclase/phosphodiesterase (Lpl0922) activities, which are all required for the survival and intracellular replication of L. pneumophila. Mutants with deletions of the corresponding genes are efficiently taken up by phagocytic cells but are partially defective for the escape of the Legionella-containing vacuole (LCV) from the host degradative endocytic pathway and result in lower survival. In addition, Lpl1118 is required for efficient endoplasmic reticulum recruitment to the LCV. Trafficking and biogenesis of the LCV are dependent upon the orchestrated actions of several type 4 secretion system Dot/Icm effectors proteins, which exhibit differentially altered translocation in the three mutants. While translocation of some effectors remained unchanged, others appeared over- and undertranslocated. A general translocation offset of the large repertoire of Dot/Icm effectors may be responsible for the observed defects in the trafficking and biogenesis of the LCV. Our results suggest that L. pneumophila uses cyclic di-GMP signaling to fine-tune effector delivery and ensure effective evasion of the host degradative pathways and establishment of a replicative vacuole. PMID:24379287