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Sample records for 2,3-cyclic-nucleotide phosphodiesterases

  1. Structural and functional evolution of 2',3'-cyclic nucleotide 3'-phosphodiesterase.

    Myllykoski, Matti; Seidel, Leonie; Muruganandam, Gopinath; Raasakka, Arne; Torda, Andrew E; Kursula, Petri

    2016-06-15

    2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) is an abundant membrane-associated enzyme within the vertebrate myelin sheath. While the physiological function of CNPase still remains to be characterized in detail, it is known - in addition to its in vitro enzymatic activity - to interact with other proteins, small molecules, and membrane surfaces. From an evolutionary point of view, it can be deduced that CNPase is not restricted to myelin-forming cells or vertebrate tissues. Its evolution has involved gene fusion, addition of other small segments with distinct functions, such as membrane attachment, and possibly loss of function at the polynucleotide kinase-like domain. Currently, it is unclear whether the enzymatic function of the conserved phosphodiesterase domain in vertebrate myelin has a physiological role, or if CNPase could actually function - like many other classical myelin proteins - in a more structural role. This article is part of a Special Issue entitled SI: Myelin Evolution. PMID:26367445

  2. Molecular cloning and characterization of rat brain 2',3'-cyclic nucleotide 3'-phosphodiesterase isoform 2.

    Gravel, M; DeAngelis, D; Braun, P E

    1994-06-15

    We have isolated a cDNA coding for the larger isoform of the rat brain 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP2), a protein associated with myelination in the central nervous system (CNS). The complete 420 amino acid sequence was deduced from the nucleotide sequence of the cDNA. Sequence comparisons show that rat CNP shares 96% homology with mouse, 84% with bovine, and 86% with human CNP. Errors in the published sequence of rat CNP1 have now been corrected. Comparisons with other proteins reveal several interesting conserved motifs, including two leucine repeat heptads, and two consensus motifs for phosphorylation in the N-terminal domain of CNP2. PMID:7932861

  3. Isoprenoid modification permits 2',3'-cyclic nucleotide 3'-phosphodiesterase to bind to membranes.

    Braun, P E; De Angelis, D; Shtybel, W W; Bernier, L

    1991-11-01

    The myelination-related enzyme 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP), a relatively abundant protein in the CNS possesses the C-terminal isoprenylation consensus domain found in a small family that includes the ras oncoproteins and their relatives, some G-proteins, and nuclear lamins. We found that CNP, like these other proteins, is modified posttranslationally by an isoprenoid derived from mevalonic acid. It appears that only the smaller of the two CNP isoforms (CNP1) is isoprenylated, but similar modification of CNP2 cannot be excluded. Inhibition of isoprenoid synthesis by Lovastatin blocks the binding of newly synthesized CNP to cell membranes; binding is restored upon addition of mevalonate to the culture medium. This shows that isoprenylation is permissive for the well-known avid association of CNP with membranes. PMID:1666129

  4. 2',3'-cyclic nucleotide 3'-phosphodiesterases inhibit hepatitis B virus replication.

    Ma, Hui; Zhao, Xing-Liang; Wang, Xue-Yan; Xie, Xing-Wang; Han, Jin-Chao; Guan, Wen-Li; Wang, Qin; Zhu, Lin; Pan, Xiao-Ben; Wei, Lai

    2013-01-01

    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. PMID:24260477

  5. Binding of 2',3'-cyclic nucleotide 3'-phosphodiesterase to myelin: an in vitro study.

    De Angelis, D A; Braun, P E

    1996-06-01

    The binding of 2', 3'-cyclic nucleotide 3'-phosphodiesterase isoform 1 (CNP1) to myelin and its association with cytoskeletal elements of the sheath have been characterized with in vitro synthesized polypeptides and purified myelin. We have previously shown that the cysteine residue present in the carboxy-terminal CXXX box of CNP1 is isoprenylated, and that both C15 farnesyl and C20 geranylgeranyl isoprenoids can serve as substrates for the modification. Here, we have mutated the CXXX box to obtain selectively farnesylated CNP1 or geranyl- geranylated CNP1 and found that these two modified forms of CNP1 behave identically in all of the assays performed. Isoprenylation is essential but not sufficient for the binding of in vitro synthesized CNP1 to purified myelin, because a control nonmyelin protein is isoprenylated, yet unable to bind to myelin. In our assay, membrane-bound CNP1 partitions quantitatively into the nonionic detergent-insoluble phase of myelin, suggesting that CNP1 binds to cytoskeletal elements within myelin. However, isoprenylated CNP1 fails to bind to the cytoskeletal matrix isolated from myelin by detergent treatment, implying that both detergent-soluble and insoluble myelin components are involved in the binding of CNP1. A model for the interactions between CNP1 and myelin is presented, consistent with models proposed for other isoprenylated proteins. PMID:8632178

  6. 2',3'-cyclic nucleotide 3'-phosphodiesterases inhibit hepatitis B virus replication.

    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.

  7. Monoclonal antibody Rip specifically recognizes 2',3'-cyclic nucleotide 3'-phosphodiesterase in oligodendrocytes.

    Watanabe, Masatomo; Sakurai, Yoko; Ichinose, Tatsuya; Aikawa, Yoshikatsu; Kotani, Masaharu; Itoh, Kouichi

    2006-08-15

    The antigen recognized with monoclonal antibody (mAb) Rip (Rip-antigen) has been long used as a marker of oligodendrocytes and myelin sheaths. However, the identity of Rip-antigen has yet to be elucidated. We herein identified the Rip-antigen. No signal recognized by mAb-Rip was detected by immunoblot analyses in the rat brain, cultured rat oligodendrocytes, or the oligodendrocyte cell line CG-4. As this antibody worked very well on immunocytochemistry and immunohistochemistry, Rip-antigen was immunopurified with mAb-Rip from the differentiated CG-4 cells. Eight strong-intensity bands thus appeared on 5-20% SDS-PAGE with SYPRO ruby fluorescence staining. To identify these molecules, each band extracted from the gel was analyzed by MALDI-QIT/TOF mass spectrometry. We found an interesting molecule in the oligodendrocytes from an approximately 44-kDa band as 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP). To test whether CNP was recognized by mAb-Rip, double-immunofluorescence staining was performed by using Alexa Fluor 488-conjugated mAb-Rip and Alexa Fluor 568-conjugated mAb-CNP in the rat cerebellum, mouse cerebellum, cultured rat oligodendrocytes, and CG-4 cells. The Rip-antigen was colocalized with CNP in these cells and tissues. To provide direct evidence that CNP was recognized by mAb-Rip, rat Cnp1-transfected HEK293T cells were used for double-immunofluorescence staining with mAb-Rip and mAb-CNP. The Rip-antigen was colocalized with CNP in rat Cnp1-transfected HEK293T cells, but the antigen was not detected by mAb-Rip and mAb-CNP in mock-transfected HEK293T cells. Overall, we have demonstrated that the antigen labeled with mAb-Rip is CNP in the oligodendrocytes. PMID:16786579

  8. 2',3'-Cyclic nucleotide 3'-phosphodiesterase binds to actin-based cytoskeletal elements in an isoprenylation-independent manner.

    De Angelis, D A; Braun, P E

    1996-09-01

    2',3'-Cyclic nucleotide 3'-phosphodiesterase (CNP) is an isoprenylated protein enriched in myelin and oligodendrocytes but also present in several other tissues at low levels. CNP binds avidly to membranes and in addition possesses several characteristics of cytoskeletal proteins. The role of isoprenylation in the association of CNP with the cytoskeleton was analyzed by ectopic expression in L cells of epitope-tagged CNP1 and a non-isoprenylated mutant CNP1. Using nonionic detergent extraction, drug-mediated cytoskeletal disruption, and coimmunoprecipitation with an anti-actin antibody, we show that CNP1 is associated with actin-based cytoskeletal elements independently of its isoprenylation status. A control protein, p21c-H-ras, which is also modified by isoprenylation at its carboxyl-terminus, does not bind to cytoskeletal structures as judged by the same criteria. We present a model that accounts for the association of CNP1 with membranes and the cytoskeleton. PMID:8752099

  9. Differential expression of 2':3'-cyclic nucleotide 3'-phosphodiesterase in cultured central, peripheral, and extraneural cells.

    Sprinkle, T J; McMorris, F A; Yoshino, J; DeVries, G H

    1985-07-01

    The relative levels of the central nervous system myelin marker enzyme 2':3'-cyclic nucleotide 3'-phosphodiesterase (EC 3.1.4.37, CNPase) were determined in neuroblastoma, astrocyte, oligodendrocyte and Schwann cell cultures and in freshly isolated human lymphocytes and platelets. The highest specific activities were associated with the cells that elaborate myelin membrane in the central and peripheral nervous system, oligodendrocytes and Schwann cells, respectively. Antiserum to bovine CNPase recognized both CNP1 and CNP2 in CNS myelin and human oligodendroglioma. In addition, a 53,000 dalton protein was evident on autoradiographs of immunoblotted PNS myelin and human oligodendroglioma proteins. Cultured rat oligodendrocyte, C6 and mouse NA neuroblastoma CNPase appear to share common determinants with the corresponding normal rat CNS enzyme. PMID:2995854

  10. 2',3'-Cyclic nucleotide 3'-phosphodiesterase: a novel RNA-binding protein that inhibits protein synthesis.

    Gravel, Michel; Robert, Francis; Kottis, Vicky; Gallouzi, Imed-Eddine; Pelletier, Jerry; Braun, Peter E

    2009-04-01

    2',3'-Cyclic nucleotide 3'-phosphodiesterase (CNP) is one of the earliest myelin-related proteins to be specifically expressed in differentiating oligodendrocytes (ODCs) in the central nervous system (CNS) and is implicated in myelin biogenesis. CNP possesses an in vitro enzymatic activity, whose in vivo relevance remains to be defined, because substrates with 2',3,-cyclic termini have not yet been identified. To characterize CNP function better, we previously determined the structure of the CNP catalytic domain by NMR. Interestingly, the structure is remarkably similar to the plant cyclic nucleotide phosphodiesterase (CPDase) from A. thaliana and the bacterial 2'-5' RNA ligase from T. thermophilus, which are known to play roles in RNA metabolism. Here we show that CNP is an RNA-binding protein. Furthermore, by using precipitation analyses, we demonstrate that CNP associates with poly(A)(+) mRNAs in vivo and suppresses translation in vitro in a dose-dependent manner. With SELEX, we isolated RNA aptamers that can suppress the inhibitory effect of CNP on translation. We also demonstrate that CNP1 can bridge an association between tubulin and RNA. These results suggest that CNP1 may regulate expression of mRNAs in ODCs of the CNS. PMID:19021295

  11. A comparative study of 2',3'-cyclic-nucleotide 3'-phosphodiesterase in vertebrates: cDNA cloning and amino acid sequences for chicken and bullfrog enzymes.

    Kasama-Yoshida, H; Tohyama, Y; Kurihara, T; Sakuma, M; Kojima, H; Tamai, Y

    1997-10-01

    In mammalian brain, two 2',3'-cyclic-nucleotide 3'-phosphodiesterase (EC 3.1.4.37) isoforms, CNP1 and CNP2, are translated, respectively, from the two mRNAs, which have been transcribed and processed by alternative use of the two transcription start points and by differential splicing. In the present study, the cDNAs encoding chicken CNP2 and bullfrog CNP1, respectively, were isolated, and the amino acid sequences of chicken CNP2 and bullfrog CNP1 were deduced. Western blot analysis showed that chicken brain contains a major CNP2-type protein together with a minor unidentified isoform, and bullfrog brain contains only a CNP1-type protein. All available amino acid sequences of vertebrate 2',3'-cyclic-nucleotide 3'-phosphodiesterases were aligned and compared. Three conserved motif sequences were noted: (a) an ATP-binding site near the amino terminus, (b) an isoprenylation site at the carboxyl terminus, and (c) a probable catalytic site resembling the active site of beta-ketoacyl synthase (EC 2.3.1.41). The second and the third motifs are conserved also in goldfish RICH (regeneration-induced 2',3'-cyclic-nucleotide 3'-phosphodiesterase homologue), which has been shown recently to have 2',3'-cyclic-nucleotide 3'-phosphodiesterase activity. The third motif (probably catalytic site) was assigned for the first time in the present report. PMID:9326261

  12. Studies on the Wolfgram high molecular weight CNS myelin proteins: relationship to 2',3'-cyclic nucleotide 3'-phosphodiesterase.

    Sprinkle, T J; Wells, M R; Garver, F A; Smith, D B

    1980-11-01

    Evidence is presented that the major protein components of the high molecular weight CNS myelin proteins designated as the Wolfgram protein doublet (W1 and W2) contain the enzyme 2',3'-cyclic nucleotide 3'-phosphodiesterase (EC 3.1.4.37, CNP). CNP is a basic hydrophobic protein containing about 830 to 840 amino acid residues. When electrophoresed on SDS polyacrylamide gels, CNP appears as a protein doublet, separated by a molecular weight difference of about 2500-3000 in bovine, human, rat, guinea pig, and rabbit. A similar protein doublet has been identified as the Wolfgram proteins W2 and W1 in myelin and in the chloroform-methanol-insoluble pellet obtained from myelin. Moreover, the relative Coomassie blue staining intensity of the CNP2 plus CNP1 protein doublet among the species examined was remarkably similar to that observed for electrophoresed myelin and chloroform-methanol-insoluble pellet derived from myelin. Antisera raised against purified bovine CNP recognized the W1 and W2 proteins isolated from bovine and human brain. The amino acid composition of pure bovine CNP is presented and compared with the compositions of several rat and bovine Wolfgram proteins obtained by other investigators. Our electrophoretic, compositional, and immunological data support the contention that the enzyme CNP is a major component of the Wolfgram protein doublet. PMID:6256502

  13. 2', 3'-cyclic nucleotide 3'-phosphodiesterase is expressed in dissociated rat cerebellar cells and included in the postsynaptic density fraction.

    Cho, Sun-Jung; Jung, Jae Seob; Jin, IngNyol; Moon, Il Soo

    2003-08-31

    We have shown by protein sequencing that the phosphotyrosine-containing 48 kDa protein band of the rat cerebellar postsynaptic density fraction (CBL-PSD) is 2', 3'-cyclic nucleotide 3'-phosphodiesterase 2 (CNP2). Immunoblot analysis indicated that both CNP1 and CNP2 isoforms are present in the CBL-PSD fraction, whereas there is little CNP2 in the forebrain (FB)-PSD fraction. Both isoforms in the CBL-PSD fraction were tyrosine-phosphorylated to a basal extent. They were efficiently dissociated from the complexes in the PSD fraction by salt, but not by non-ionic detergents such as n-octyl glucoside (OG) and Triton X-100. Immunocytochemistry of dissociated cerebellar cultures revealed patchy CNP staining in oligodendrocytes (OLs), Purkinje cells (PCs), and unidentified PSD95-positive cells, but no staining in granule cells (GCs). Our results indicate that both CNP1 and CNP2 are expressed in cerian populations of cerebellar cells in addition to OL, and that they are associated with complexes that are co-isolated with the PSD. PMID:14503857

  14. 2',3'-cyclic nucleotide-3'-phosphodiesterase in the central nervous system is fatty-acylated by thioester linkage.

    Agrawal, H C; Sprinkle, T J; Agrawal, D

    1990-07-15

    2',3'-Cyclic nucleotide-3'-phosphodiesterase (CNP1 and CNP2 with Mr of 46,000 and 48,000, respectively) is the major enzyme of central nervous system myelin. It is associated with oligodendroglial plasma membrane and uncompacted myelin (myelin-like fraction), which are in contact with glial cytoplasm. Proteins of the myelin-like fraction were labeled with [3H]palmitic acid in brain slices from 17-day-old rats and immunoprecipitated with anti-CNP antiserum. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography of immunoprecipitated material revealed intense acylation of CNP1 and CNP2, and radioactivity was released by hydroxylamine. Palmitic acid was covalently bound to CNP because radioactivity was not removed by extraction of immunoprecipitated CNP with organic solvent or by boiling in sodium dodecyl sulfate and dithiothreitol. However, treatment of immunoprecipitated CNP with (a) hydroxylamine-released palmitohydroxamate and palmitic acid, (b) sodium borohydride-released hexadecanol, and (c) methanolic-KOH-released methyl palmitate. Synthesis, acylation, or transport of CNP was not affected by monensin or colchicine. However, acylation of CNP was inhibited 24-32% by cycloheximide. These results provide conclusive evidence that CNP1 and CNP2 are fatty acid acylated with palmitate through a thioester linkage and is posttranslationally modified sometime after synthesis. PMID:2164018

  15. Selective synthesis of 2',3'-cyclic nucleotide 3'-phosphodiesterase isoform 2 and identification of specifically phosphorylated serine residues.

    O'Neill, R C; Braun, P E

    2000-02-01

    2',3'-Cyclic nucleotide 3'-phosphodiesterase (CNP) is a protein found abundantly in the cytoplasmic compartments of CNS myelin. Two isoforms of this protein, CNP1 and CNP2, are detectable. They differ by a 20-amino acid extension exclusive to CNP2. Additionally, CNP2 is essentially the only isoform to be phosphorylated in vivo. In this study, we examine the phosphorylation of CNP2 in transfected cells. CNP2 was selectively expressed ectopically in 293T cells and labeled with 32P. Immunoprecipitation of labeled CNP2 and tryptic phosphopeptide mapping analyses identified serines 9 and 22 as the major sites of phosphorylation. Only serine 22 was phosphorylated initially in oligodendrocyte-enriched cultures of neonatal rat brain glial cells. However, 4beta-phorbol 12,13-dibutyrate (PDB) induced the phosphorylation of serine 9, thereby producing the same pattern seen in 293T cells. These results suggest that serine 9 is phosphorylated by a PDB-sensitive kinase, likely protein kinase C, and that serine 22 appears to be constitutively phosphorylated. PMID:10646504

  16. Nonspecific association of 2',3'-cyclic nucleotide 3'-phosphodiesterase with the rat forebrain postsynaptic density fraction.

    Cho, Sun-Jung; Jung, Jae Seob; Shin, Seung Chul; Jin, IngNyol; Ko, Bok Hyun; Kim Kwon, Yunhee; Suh-Kim, Haeyoung; Moon, Il Soo

    2003-12-31

    The 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP), a protein of unknown function in vivo, is abundantly expressed in myelinating glia in two isoforms, CNP1 and CNP2. In this study, immunoblot analysis showed that CNP1 is the major isoform in adult forebrain, and that both isoforms are included in the postsynaptic density (PSD) fraction and tyrosine-phosphorylated at the basal level. However, subcellular distribution and detergent extraction data showed that CNP is nonspecifically associated with the PSD fraction. Immunocytochemistry revealed that CNP is detected, in a weak but punctate pattern, in dissociated rat hippocampal neurons of 3 days to 2 weeks in vitro. The CNP-positive punctae were distributed throughout soma and dendrites, and distinct from PSD95-positive ones. Immunoblot analysis indicated that CNP is also expressed in neuronal stem cell lines, HiB5 and F11. Interestingly, in addition to the known two isoforms, a new CNP isoform of MW 45 kDa was expressed in these cell lines and was the major type of isoform in F11 cells. Taken together, our data suggest that CNP is expressed in the early stage of in vitro development and nonspecifically included in the adult rat PSD fraction. PMID:14749525

  17. A rabbit autoantibody specific for the 46-kDa form of 2',3'-cyclic nucleotide 3'-phosphodiesterase.

    Möller, J R; Ramaswamy, S G; Jacobowitz, D M; Quarles, R H

    1992-05-01

    An autoantibody occurring in the serum of an apparently normal rabbit that immunocytochemically stains myelin sheaths and oligodendrocytes in rat brain was shown to react specifically with the 46-kDa isoform of 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP) (EC 3.1.4.37) in a number of species. Identification of the shorter isoform of the enzyme (CNP1) as the antigen was achieved by comparing the immunostaining of Western blots by the autoantibody with that of a well-characterized anti-CNP antiserum. The 46-kDa antigen reacting with the autoantibody exhibited the same Mr and pI as the small isoform of CNP on two-dimensional gels and showed a similar enrichment in purified CNS myelin. The autoantibody has very high affinity for CNP1 and is capable of detecting the very low amounts of this enzyme in peripheral nerve, spleen, adrenal gland, pancreas, testis, and intestine. Testing the reactivity of the autoantibody with synthetic peptides by enzyme-linked immunosorbent assay revealed that it reacted with the N-acetylated decapeptide corresponding to the N-terminus of CNP1, but did not react if the peptide was not acetylated or if the acetyl group was replaced with a palmityl group. The lack of reactivity with CNP2, which differs from CNP1 by a 20-amino acid extension at the N-terminus of the protein as a result of alternative splicing, may be due to the absence of the N-acetyl moiety that is part of the epitope and/or blocking of antibody binding to the decapeptide by extension of the polypeptide chain.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1373178

  18. Transcriptional regulation of 2',3'-cyclic nucleotide 3'-phosphodiesterase gene expression by cyclic AMP in C6 cells.

    Gravel, M; Gao, E; Hervouet-Zeiber, C; Parsons, V; Braun, P E

    2000-11-01

    It was recently shown that the two transcripts encoding the isoforms of 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP1 and CNP2) are differentially regulated during the process of oligodendrocyte maturation. In oligodendrocyte precursors, only CNP2 mRNA is present, whereas in differentiating oligodendrocytes, both CNP1 and CNP2 mRNAs are expressed. This pattern of CNP expression is likely due to stage-specific transcriptional regulation of the two CNP promoters during the process of oligodendrocyte differentiation. Here, we report the influence of increased intracellular cyclic AMP (cAMP) levels on the transcription of both CNP1 and CNP2 mRNAs in rat C6 glioma cells. We found that the transcription of CNP1 mRNA was significantly increased in comparison with that of CNP2 mRNA in cells treated with cAMP analogues to elevate intracellular cAMP levels. This up-regulation of CNP1 expression (a) is due to an increase of transcription, (b) requires de novo protein synthesis, and (c) requires the activity of protein kinase A. These results are physiologically significant and support the idea that a cAMP-mediated pathway is part of the molecular mechanisms regulating the expression of CNP1 in oligodendrocytes. The regulation of CNP1 promoter activity by cAMP was then investigated in stably transfected C6 cell lines containing various deletions of the CNP promoter directing the bacterial chloramphenicol acetyltransferase gene. We showed that the sequence between nucleotides -126 and -102 was essential for the cAMP-dependent induction of CNP1 expression. Gel retardation analysis showed that two protein-DNA complexes are formed between this sequence and nuclear factors from C6 cells treated or not treated with cAMP. This suggests that the induction of CNP1 mRNA transcription is not mediated by changes in binding of nuclear factors that interact directly with the -126/-102 sequence. Sequence analysis of this region revealed the presence of a putative activator protein-2 (AP

  19. Expression, purification, and initial characterization of different domains of recombinant mouse 2',3'-cyclic nucleotide 3'-phosphodiesterase, an enigmatic enzyme from the myelin sheath

    Kursula Petri

    2010-01-01

    Full Text Available Abstract Background 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase is an enigmatic enzyme specifically expressed at high levels in the vertebrate myelin sheath, whose function and physiological substrates are unknown. The protein consists of two domains: an uncharacterized N-terminal domain with little homology to other proteins, and a C-terminal phosphodiesterase domain. Findings In order to be able to fully characterize CNPase structurally and functionally, we have set up expression systems for different domains of CNPase, using a total of 18 different expression constructs. CNPase was expressed in E. coli with a TEV-cleavable His-tag. Enzymatic activity assays indicated that the purified proteins were active and correctly folded. The folding of both the full-length protein, as well as the N- and C-terminal domains, was also studied by synchrotron CD spectroscopy. A thermal shift assay was used to optimize buffer compositions to be used during purification and storage. The assay also indicated that CNPase was most stable at a pH of 5.5, and could be significantly stabilized by high salt concentrations. Conclusions We have been able to express and purify recombinantly several different domains of CNPase, including the isolated N-terminal domain, which is folded mainly into a β-sheet structure. The expression system can be used as an efficient tool to elucidate the role of CNPase in the myelin sheath.

  20. gRICH68 and gRICH70 are 2',3'-cyclic-nucleotide 3'-phosphodiesterases induced during goldfish optic nerve regeneration.

    Ballestero, R P; Wilmot, G R; Agranoff, B W; Uhler, M D

    1997-04-25

    Biochemical characterization of changes in gene expression that accompany optic nerve regeneration has led to the identification of proteins that may play key roles in the regeneration process. In this report, a cDNA encoding gRICH70, a novel isoform of the regeneration-induced gRICH68 protein, has been identified and characterized in goldfish. Both gRICH68 and gRICH70 show significant homology (34-36%) to mammalian 2',3'-cyclic-nucleotide 3'-phosphodiesterases (CNPases), hence the name goldfish regeneration-induced CNPase homolog (gRICH). The predicted 431-amino acid gRICH70 protein is 88% homologous to gRICH68, and the retinal mRNA for gRICH70 is coordinately induced with gRICH68 mRNA during optic nerve regeneration. Enzymatic analysis of recombinant proteins confirms that both gRICH proteins possess CNPase activity. Despite the relatively limited sequence homology, the kinetic constants obtained suggest that both gRICH proteins are at least as efficient as recombinant mouse CNP1 in catalyzing the hydrolysis of 2',3'-cAMP. Immunoprecipitation studies indicate that gRICH proteins are responsible for the majority of the CNPase activity detected in regenerating goldfish retinas. The evidence presented demonstrates that gRICH68 and gRICH70 correspond to a previously described doublet of acidic proteins that are selectively induced in the goldfish retina during optic nerve regeneration. Thus, CNPase enzyme activity is implicated for the first time in the process of nerve regeneration. PMID:9111061

  1. 2', 3'-Cyclic nucleotide 3'-phosphodiesterase cells derived from transplanted marrow stromal cells and host tissue contribute to perineurial compartment formation in injured rat spinal cord.

    Cao, Qiong; Ding, Peng; Lu, Jia; Dheen, S Thameem; Moochhala, Shabbir; Ling, Eng-Ang

    2007-01-01

    Transdifferentiation of transplanted marrow stromal cells (MSCs) and reactive changes of glial cells in a completely transected rat spinal cord were examined. Marrow stromal cells exhibited 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP) at the plasma membrane and this has allowed their identification after transplantation by immunoelectron microscopy. In the control rats, the lesion site showed activated microglia/neural macrophages and some elongated cells, whose cytoplasm was immunoreactive for CNP. Cells designated as CNP1 and apparently host-derived expressed CXCR4. In experimental rats receiving MSCs transplantation, CNP1 cells were increased noticeably. This was coupled with the occurrence of a different subset of CNP cells whose plasma membrane was CNP-immunoreactive and expressed CXCR4. These cells, designated as CNP2, enclosed both myelinated and unmyelinated neurites thus assuming a spatial configuration resembling that of Schwann cells. A remarkable feature was the extensive ramifications of CNP1 cells with long filopodia processes delineating the CNP2 cells and their associated neurites, forming many perineurial-like compartments. Present results have shown that CNP2 cells considered to be MSCs-derived can transform into cells resembling Schwann cells based on their spatial relation with the regenerating nerve fibers, whereas the CNP1 glial cells participate in formation of perineurial compartments, probably serving as conduits to guide the nerve fiber growth. The chemotactic migration of CNP cells either derived from host tissue or MSCs bearing CXCR4 may be attracted by stromal derived factor-1alpha (SDF-1alpha) produced locally. The coordinated cellular interaction between transplanted MSCs and local glial cells may promote the growth of nerve fibers through the lesion site. PMID:17061258

  2. 2',3'-cyclic nucleotide 3'-phosphodiesterase, an oligodendrocyte-Schwann cell and myelin-associated enzyme of the nervous system.

    Sprinkle, T J

    1989-01-01

    2',3'-Cyclic nucleotide 3'-phosphohydrolase (E.C. 3.1.4.37; CNPase) is a myelin-associated enzyme. In central and peripheral nervous system tissues, the enzyme is localized almost exclusively in the two cell types that elaborate myelin, the oligodendrocyte and the Schwann cell, respectively. Nonneural sources of CNPase have also been described, but they all have much lower activities than those found in brain. The freshly isolated brain enzymes appear as closely spaced doublets at approximately 46 and 48 kDa on SDS-PAGE. The primary sequence appears highly conserved between these two proteins, designated CNP1 and CNP2. Major structural differences between these two proteins are most likely due to posttranslational modifications of the enzyme itself (certainly phosphorylation, possibly others) or to alternative splicing. The primary sequences of rat and bovine brain CNPase have now been deduced from the cDNA sequences and the enzymes appear to be unique. Current research suggests that CNPase is involved in the very rapid growth of myelin membrane during early oligodendrocyte membrane biogenesis and possibly maintenance. The absolute hydrolysis specificity, yielding 2'-mononucleotides from 2',3'-cyclic substrates, strongly suggests that CNPase is a nucleic acid enzyme, possibly related to RNA metabolism. PMID:2537684

  3. Identification of essential residues in 2',3'-cyclic nucleotide 3'-phosphodiesterase. Chemical modification and site-directed mutagenesis to investigate the role of cysteine and histidine residues in enzymatic activity.

    Lee, J; Gravel, M; Gao, E; O'Neill, R C; Braun, P E

    2001-05-01

    2',3'-Cyclic nucleotide 3'-phosphodiesterase (CNP; EC ) catalyzes in vitro hydrolysis of 3'-phosphodiester bonds in 2',3'-cyclic nucleotides to produce 2'-nucleotides exclusively. N-terminal deletion mapping of the C-terminal two-thirds of recombinant rat CNP1 identified a region that possesses the catalytic domain, with further truncations abolishing activity. Proteolysis and kinetic analysis indicated that this domain forms a compact globular structure and contains all of the catalytically essential features. Subsequently, this catalytic fragment of CNP1 (CNP-CF) was used for chemical modification studies to identify amino acid residues essential for activity. 5,5'-Dithiobis-(2-nitrobenzoic acid) modification studies and kinetic analysis of cysteine CNP-CF mutants revealed the nonessential role of cysteines for enzymatic activity. On the other hand, modification studies with diethyl pyrocarbonate indicated that two histidines are essential for CNPase activity. Consequently, the only two conserved histidines, His-230 and His-309, were mutated to phenylalanine and leucine. All four histidine mutants had k(cat) values 1000-fold lower than wild-type CNP-CF, but K(m) values were similar. Circular dichroism studies demonstrated that the low catalytic activities of the histidine mutants were not due to gross changes in secondary structure. Taken together, these results demonstrate that both histidines assume critical roles for catalysis. PMID:11278504

  4. Gp66, a calcineurin family phosphatase encoded by mycobacteriophage D29, is a 2', 3' cyclic nucleotide phosphodiesterase that negatively regulates phage growth.

    Dutta, Soumita; Bhawsinghka, Niketa; Das Gupta, Sujoy K

    2014-10-13

    Mycobacteriophage D29 encodes a protein Gp66 which has been predicted to be a calcineurin family phosphoesterase. Phylogenetically Gp66 and related proteins mostly derived from mycobacteriophages form a distinct clade within this family. Interestingly, the presence of gene 66 orthologs can be traced to bacteria of diverse phylogenetic lineages such as Aquifex aeolicus, a deep branching eubacteria and Methanococcus jannaschii, an archaebacteria. The promiscuous nature of gene 66 suggests that it may have been transferred across genus barriers by horizontal gene transfer mechanisms. The biological function of members of this novel clade comprising mostly the mycobacteriophage phosphoesterases have not been elucidated so far. In this investigation, it has been demonstrated for the first time that Gp66, a member of this novel family, is a 2', 3' cyclic phosphodiesterase. The gene is expressed during phage infection and the net result is negative regulation of bacteriophage as well as bacterial growth. PMID:25307893

  5. Monoclonal antibody production to human and bovine 2':3'-cyclic nucleotide 3'-phosphodiesterase (CNPase): high-specificity recognition in whole brain acetone powders and conservation of sequence between CNP1 and CNP2.

    Sprinkle, T J; Agee, J F; Tippins, R B; Chamberlain, C R; Faguet, G B; De Vries, G H

    1987-11-24

    Monoclonal antibodies against human and bovine 2':3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) were generated by fusing FOX-NY myeloma cells with spleen cells from RBF/Dn mice previously immunized with the purified brain antigens. The enzyme isolated from bovine brain was quite basic, with an isoelectric point of 9.71 and both the bovine and human enzymes consisted of a closely spaced doublet at approximately 44 and 46 kDa on SDS-PAGE. Six monoclonals were were identified as strongly recognizing the enzyme on both ELISA plates and on immunoblots of whole brain protein. Four monoclonals very weakly cross-reacted with guinea pig myelin basic protein. In contrast with two previous reports, some of our monoclonal antibodies did immunostain 2 or 3 protein bands in peripheral nerve, two bands closely corresponding to those immunostained in central nervous system (CNS) myelin, the Wolfgram protein fraction and in acetone powders of whole brain. Each of the 6 monoclonals reacting strongly on immunoblots recognized the enzyme in from 2 to 5 of the species examined (human, bovine, rat, mouse and rabbit). In addition, all 6 monoclonals that immunostained the enzyme in whole brain, myelin and Wolfgram protein immunoblots recognized both CNP1 (44 kDa) and CNP2 (46 kDa). The two closely spaced protein bands observed on SDS-PAGE and previously stained on immunoblots of CNS CNPase using polyvalent rabbit anti-bovine CNPase antisera, and now different monoclonal antibodies, appear to be immunologically related and to contain highly conserved sequences. PMID:2446713

  6. Insulin: its binding to specific receptors and its stimulation of DNA synthesis and 2',3'-cyclic nucleotide phosphohydrolase in embryonic mouse brain cell cultures

    Previously, the authors demonstrated that ornithine decarboxylase was stimulated by insulin in cultures of embryonic mouse brain cells. In the present work, they have investigated the presence and specificity of insulin receptors in these cultures. A time study showed that maximum binding of 125[I] labelled insulin was around 75 min. Other studies measured the influence of concentration and age on insulin binding. A displacement study using increasing concentrations of cold insulin, glucagon or growth hormone demonstrated that the specificity of the receptors for insulin was rather high. It was also found that insulin displayed a clear dose-dependent stimulation of thymidine incorporation into the brain cells. Insulin also stimulated the glial enzyme 2':3'-cyclic nucleotide phosphohydrolase (CNP-ase). The results suggest a dual role for insulin; it regulates both cell proliferation as well as differentiation

  7. In vivo phosphorylation of 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNP): CNP in brain myelin is phosphorylated by forskolin- and phorbol ester-sensitive protein kinases.

    Agrawal, H C; Sprinkle, T J; Agrawal, D

    1994-06-01

    2',3'-cyclic nucleotide 3'-phosphohydrolase (CNP) was phosphorylated in vivo, in brain slices and in a cell free system. Phosphoamino acid analysis of immunoprecipitated CNP labeled in vivo and in brain slices revealed phosphorylation of phosphoserine (94%) and phosphothreonine (5%) residues. Phosphorylation of CNP increased by 3-fold after brain slices were incubated with forskolin. Similarly, incubation of isolated myelin with [gamma-32]ATP with cAMP (5 microM) and cAMP (5 microM)+catalytic unit of cAMP dependent protein kinase dramatically increased CNP2 phosphorylation by 4- and 6-fold, respectively. It is feasible that CNP2 was predominantly phosphorylated on serine and/or threonine residues of the amino terminal peptide of CNP2, and this phosphorylation was catalyzed by protein kinase A. Phosphorylation of CNP1 and CNP2 increased 2-fold by incubating brain slices with phorbol ester. Forskolin and phorbol ester increased the phosphorylation of single, but distinct, CNP peptides. We present the first biochemical evidence that CNP2, on a protein mass basis, is far more heavily phosphorylated than CNP1, suggesting there are more phosphorylation sites on CNP2 than CNP1 and that at least one site is located on the 20-amino acid terminus of CNP2 and that it is likely a PKA site. PMID:8065530

  8. 2’,3’-Cyclic Nucleotide 3’-Phosphodiesterases Inhibit Hepatitis B Virus Replication

    Hui Ma; Xing-Liang Zhao; Xue-Yan Wang; Xing-Wang Xie; Jin-Chao Han; Wen-Li Guan; Qin Wang; Lin Zhu; Xiao-Ben Pan; Lai Wei

    2013-01-01

    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 polyadeny...

  9. Phosphodiesterase-5 inhibitors.

    Cockrill, Barbara A; Waxman, Aaron B

    2013-01-01

    Nitric oxide (NO) signaling plays a key role in modulating vascular tone and remodeling in the pulmonary circulation. The guanylate cyclase/cyclic guanylate monophosphate-signaling pathway primarily mediates nitric oxide signaling. This pathway is critical in normal regulation of the pulmonary vasculature, and is an important target for therapy in patients with pulmonary hypertension. In the pulmonary vasculature, degradation of cGMP is primarily regulated by PDE-5, and inhibition of this enzyme has important effects on pulmonary vasculature smooth muscle tone. Large randomized placebo-controlled trials of PDE-5 inhibitors demonstrated improved exercise capacity, hemodynamics and quality of life in adult patients with PAH. This chapter will discuss the mechanisms of NO signaling in the vasculature, characteristics of the PDE5-inhibitors approved for treatment of PH, and review available data on the use of phosphodiesterase inhibitors in PH. PMID:24092343

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

    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.

  11. Current use of phosphodiesterase inhibitors in urology

    Hakky, Tariq Said; Jain, Lakshay

    2015-01-01

    The causes of male erectile dysfunction (ED) are quite variable and are now commonly divided into etiologies such as ischemia, smooth muscle damage, or altered blood flow. Although varying rates of ED have been reported in literature, the number of men with ED is projected to increase worldwide by 2025 to approximately 322 million. Since the introduction of phosphodiesterase 5 (PDE5) inhibitors, there has been a paradigm shift in the treatment of ED because PDE5 inhibitors address a broad spe...

  12. Sequence Conservation of Glycerophosphodiester Phosphodiesterase among Treponema pallidum Strains

    Cameron, Caroline E.; Castro, Christa; Lukehart, Sheila A.; Van Voorhis, Wesley C.

    1999-01-01

    Previous investigations have demonstrated that immunization with Treponema pallidum subsp. pallidum glycerophosphodiester phosphodiesterase significantly protects rabbits from subsequent treponeme challenge. In this report, we show that the glycerophosphodiester phosphodiesterase amino acid sequence is conserved among 12 strains from a total of five pathogenic treponemes. The invariant nature of this immunoprotective antigen makes it an attractive candidate for inclusion in a universal subuni...

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

    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

  14. Cyclic nucleotide specific phosphodiesterases of Leishmania major

    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

  15. Cyclic adenosine monophosphate phosphodiesterase in brain: effect on anxiety.

    Beer, B; Chasin, M; Clody, D E; Vogel, J R

    1972-04-28

    Drugs that reduce anxiety may be mediated by cyclic adenosine monophosphate in the brain because (i) potent anxiety-reducing drugs are also potent inhibitors of brain phosphodiesterase activity; (ii) dibutyryl cyclic adenosine monophosphate has the ability to reduce anxiety; (iii) the methylxanthines show significant anxiety-reducing effects; (iv) theophylline and chlordiazepoxide produce additive anxiety-reducing activity; and (v) there is a significant correlation between the anxiety-reducing property of drugs and their ability to inhibit phosphodiesterase activity in the brain. PMID:4402069

  16. Characterization of inhibitors of phosphodiesterase 1C on a human cellular system.

    Dunkern, Torsten R; Hatzelmann, Armin

    2007-09-01

    Different inhibitors of the Ca(2+)/calmodulin-stimulated phosphodiesterase 1 family have been described and used for the examination of phosphodiesterase 1 in cellular, organ or animal models. However, the inhibitors described differ in potency and selectivity for the different phosphodiesterase family enzymes, and in part exhibit additional pharmacodynamic actions. In this study, we demonstrate that phosphodiesterase 1C is expressed in the human glioblastoma cell line A172 with regard to mRNA, protein and activity level, and that lower activities of phosphodiesterase 2, phosphodiesterase 3, phosphodiesterase 4 and phosphodiesterase 5 are also present. The identity of the phosphodiesterase 1C activity detected was verified by downregulation of the mRNA and protein through human phosphodiesterase 1C specific small interfering RNA. In addition, the measured K(m) values (cAMP, 1.7 microm; cGMP, 1.3 microm) are characteristic of phosphodiesterase 1C. We demonstrate that treatment with the Ca(2+) ionophore ionomycin increases intracellular Ca(2+) in a concentration-dependent way without affecting cell viability. Under conditions of enhanced intracellular Ca(2+) concentration, a rapid increase in cAMP levels caused by the adenylyl cyclase activator forskolin was abolished, indicating the involvement of Ca(2+)-activated phosphodiesterase 1C. The reduction of forskolin-stimulated cAMP levels was reversed by phosphodiesterase 1 inhibitors in a concentration-dependent way. Using this cellular system, we compared the cellular potency of published phosphodiesterase 1 inhibitors, including 8-methoxymethyl-3-isobutyl-1-methylxanthine, vinpocetine, SCH51866, and two established phosphodiesterase 1 inhibitors developed by Schering-Plough (named compounds 31 and 30). We demonstrate that up to 10 microm 8-methoxymethyl-3-isobutyl-1-methylxanthine and vinpocetine had no effect on the reduction of forskolin-stimulated cAMP levels by ionomycin, whereas the more selective and up to 10

  17. A Sensitive Cyclic Nucleotide Phosphodiesterase Assay for Transient Enzyme Kinetics

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

    1983-01-01

    A new assay for cyclic nucleotide phosphodiesterase has been developed by using reverse-phase column chromatography for the separation of product and substrate of the enzymatic reaction. The polar 5'-nucleotides are not retarded by the column, while the more lipophilic cyclic nucleotides bind to the

  18. Upregulation of Phosphodiesterase type 5 in the Hyperplastic Prostate

    Wenhao Zhang; Ning Zang; Yaoming Jiang; Ping Chen; Xinghuan Wang; Xinhua Zhang

    2015-01-01

    Both 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 ED. However, the influence of BPH on prostatic PDE5 expression has never been studied. A testosterone-induced rat model of BPH was developed and human hyperplastic prostate specimens were harvested during cysto...

  19. Emerging new uses of phosphodiesterase-5 inhibitors in cardiovascular diseases

    Kukreja, Rakesh C.; Salloum, Fadi N.; Das, Anindita; Koka, Saisudha; Ockaili, Ramzi A; Xi, Lei

    2011-01-01

    Phosphodiesterase type-5 (PDE-5) inhibitors – sildenafil, vardenafil and tadalafil – have been successfully used to treat male erectile dysfunction. In 2006, sildenafil and tadalafil were among the 75 most popular prescription drugs in the United States. Recent studies suggest that these PDE-5 inhibitors could be used as novel drug therapies for cardiac hypertrophy, cardiomyopathy, heart failure, stroke, neurodegenerative diseases and other circulatory disorders. This reviews discusses these ...

  20. Counterfeit phosphodiesterase type 5 inhibitors pose significant safety risks

    Jackson, G; Arver, S; Banks, I.; Stecher, V J

    2010-01-01

    Counterfeit drugs are inherently dangerous and a growing problem; counterfeiters are becoming increasingly sophisticated. Growth of the counterfeit medication market is attributable in part to phosphodiesterase type 5 inhibitor (PDE5i) medications for erectile dysfunction (ED). Millions of counterfeit PDE5is are seized yearly and account for the bulk of all counterfeit pharmaceutical product seizures. It has been estimated that up to 2.5 million men in Europe are exposed to illicit sildenafil...

  1. Specific Inhibition of Phosphodiesterase-4B Results in Anxiolysis and Facilitates Memory Acquisition

    McGirr, A; Lipina, TV; Mun, HS; Georgiou, J.; Al-Amri, AH; Ng, E; Zhai, D; Elliott, C; Cameron, RT; Mullins, JGL; Liu, F; Baillie, GS; Clapcote, SJ; Roder, JC

    2016-01-01

    Cognitive dysfunction is a core feature of dementia and a prominent feature in psychiatric disease. As non-redundant regulators of intracellular cAMP gradients, phosphodiesterases (PDE) mediate fundamental aspects of brain function relevant to learning, memory, and higher cognitive functions. Phosphodiesterase-4B (PDE4B) is an important phosphodiesterase in the hippocampal formation, is a major Disrupted in Schizophrenia 1 (DISC1) binding partner and is itself a risk gene for psychiatric illn...

  2. Substrate Specificity of Cyclic Nucleotide Phosphodiesterase from Beef Heart and from Dictyostelircm discoideum

    Haastert, Peter J.M. van; Dijkgraaf, Peter A.M.; Konijn, Theo M.; Abbad, Emilio Garcia; Petridis, Georg; Jastorff, Bernd

    1983-01-01

    The substrate specificity of beef heart phosphodiesterase activity and of the phosphodiesterase activity at the cell surface of the cellular slime mold Dictyostelium discoideum has been investigated by measuring the apparent Km and maximal velocity (V) of 24 derivatives of adenosine 3’,5’-monophosph

  3. Beta-adrenoceptor responsiveness in intact leukocytes from adults and newborn infants; effect of phosphodiesterase inhibitors

    Foged, N; Bertelsen, Niels Haldor; Johansen, Torben

    1990-01-01

    of the method is dependent on the activity of the cAMP phosphodiesterase inside the cells. The xanthine derivatives, theophylline (4 mmol l-1) and 3-isobutyl-l-methyl-xanthine (0.1-2.5 mmol l-1), were used to inhibit the cAMP phosphodiesterase activity. It appears that 3-isobutyl-l-methyl-xanthine at...

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

    Birk, Steffen; Edvinsson, Lars; Olesen, Jes; Kruuse, Christina Rostrup

    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...

  5. Cyclic AMP phosphodiesterase in Salmonella typhimurium: characteristics and physiological function.

    Botsford, J L

    1984-01-01

    The physiological function of cyclic AMP (cAMP) phosphodiesterase in Salmonella typhimurium was investigated with strains which were isogenic except for the cpd locus. In crude broken-cell extracts the properties of the enzyme were found to be similar to those reported for Escherichia coli. The specific activity in the mutant was less than 1% that in the wild type. Rates of cAMP production in the mutant were as much as twice those observed in the wild type. The amount of cAMP accumulated when...

  6. AB030. Evolution of phosphodiesterase type 5 inhibitors

    Moon, Du Geon

    2016-01-01

    After launching of sildenafil citrate, the last invention of 20th century, in 1998, oral phosphodiesterase type 5 (PDE5) inhibitor has been established as first line treatment of erectile dysfunction and shift new paradigm of diagnosis and treatment of erectile dysfunction. The big success of sildenafil in pharmaceutical R&D induced the consecutive development of the so-called ‘The second Viagra’, e.g., tadalafil and vardenafil in 2003. Currently, these 3 kinds of PDE5 inhibitors are most fam...

  7. Role of phosphodiesterase 5 in synaptic plasticity and memory

    Daniela Puzzo

    2008-04-01

    Full Text Available Daniela Puzzo1,2, Salvatore Sapienza1, Ottavio Arancio2, Agostino Palmeri11Dept of Physiological Sciences, University of Catania, Catania, Italy; 2Dept of Pathology, Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University, New York, NY, USAAbstract: Phosphodiesterases (PDEs are enzymes that break down the phosphodiesteric bond of the cyclic nucleotides, cAMP and cGMP, second messengers that regulate many biological processes. PDEs participate in the regulation of signal transduction by means of a fine regulation of cyclic nucleotides so that the response to cell stimuli is both specific and activates the correct third messengers. Several PDE inhibitors have been developed and used as therapeutic agents because they increase cyclic nucleotide levels by blocking the PDE function. In particular, sildenafil, an inhibitor of PDE5, has been mainly used in the treatment of erectile dysfunction but is now also utilized against pulmonary hypertension. This review examines the physiological role of PDE5 in synaptic plasticity and memory and the use of PDE5 inhibitors as possible therapeutic agents against disorders of the central nervous system (CNS.Keywords: phosphodiesterase 5, NO/cGMP pathway, sildenafil, synaptic plasticity, memory, Alzheimer’s disease

  8. [Phosphodiesterase-5 inhibitors for the treatment of pulmonary arterial hypertension].

    Beltrán-Gámez, Miguel E; Sandoval-Zárate, Julio; Pulido, Tomás

    2015-01-01

    In experimental and clinical cardiology, phosphodiesterase type 5 (PDE-5) inhibitors have brought scientific interest as a therapeutic tool in pulmonary arterial hypertension (PAH) management in recent years. Phosphodiesterases are a superfamily of enzymes that inactivate cyclic adenosine monophosphate and cyclic guanosine monophosphate, the second messengers of prostacyclin and nitric oxide. The rationale for the use of PDE-5 inhibitors in PAH is based on their capacity to overexpresss the nitric oxide pathway pursued inhibition of cyclic guanosine monophosphate hydrolysis. By increasing cyclic guanosine monophosphate levels it promotes vasodilation, antiproliferative and pro-apoptotic effects that may reverse pulmonary vascular remodeling. There is also evidence that these drugs may directly enhance right ventricular contractility through an increase in cyclic adenosine monophosphate mediated by the inhibition of the cyclic guanosine monophosphate -sensitive PDE-3. Sildenafil, tadalafil and vardenafil are 3 specific PDE-5 inhibitors in current clinical use, which share similar mechanisms of action but present some significant differences regarding potency, selectivity for PDE-5 and pharmacokinetic properties. Sildenafil received approval in 2005 by the Food and Drug Administration and the European Medicines Agency and tadalafil in 2009 by the Food and Drug Administration and the European Medicines Agency for the treatment of PAH in patients classified as NYHA/WHO functional class II and III. In Mexico, sildenafil and tadalafil were approved by Comisión Federal de Protección contra Riesgos Sanitarios for this indication in 2010 and 2011, respectively. PMID:26047999

  9. Determination of phosphodiesterase I activity in human blood serum.

    Hynie, I; Meuffels, M; Poznanski, W J

    1975-09-01

    Phosphodiesterase I (EC 3.1.4.1) activity was detected in normal human blood serum. The enzyme is stable at laboratory temperature for three days, but is inactivated at pH less than 7. The pH for optimum activity increases with the substrate concentration (under the conditions used, from pH 9.0 to 10.2) and, conversely, the Km increases with pH and buffer concentration. The enzyme is inhibited by ethylenediaminetetraacetate but not by phosphate (0.1 mol/liter). We developed a simple quantitative method for its determination, based on hydrolysis of the p-nitrophenyl ester of thymidine 5'-monophosphate and subsequent measurement of the liberated p-nitrophenol at 400 nm in NaOH (0.1 mol/liter). Normal values (mean +/- 2 SD) were determined to be 33 +/- 6.4 U/liter. Preliminary studies indicate that phosphodiesterase I activity is greater than normal in serum of patients with necrotic changes in the liver or kidney or in cases of breast cancer, but not in that of patients with myocardial infarction, bone cancer, lung cancer, or chronic liver cirrhosis. PMID:168991

  10. Expression and Genetic Activation of Cyclic Di-GMP-Specific Phosphodiesterases in Escherichia coli

    Reinders, Alberto; Hee, Chee-Seng; Ozaki, Shogo; Mazur, Adam; Boehm, Alex; Schirmer, Tilman

    2015-01-01

    ABSTRACT Intracellular levels of the bacterial second messenger cyclic di-GMP (c-di-GMP) are controlled by antagonistic activities of diguanylate cyclases and phosphodiesterases. The phosphodiesterase PdeH was identified as a key regulator of motility in Escherichia coli, while deletions of any of the other 12 genes encoding potential phosphodiesterases did not interfere with motility. To analyze the roles of E. coli phosphodiesterases, we demonstrated that most of these proteins are expressed under laboratory conditions. We next isolated suppressor mutations in six phosphodiesterase genes, which reinstate motility in the absence of PdeH by reducing cellular levels of c-di-GMP. Expression of all mutant alleles also led to a reduction of biofilm formation. Thus, all of these proteins are bona fide phosphodiesterases that are capable of interfering with different c-di-GMP-responsive output systems by affecting the global c-di-GMP pool. This argues that E. coli possesses several phosphodiesterases that are inactive under laboratory conditions because they lack appropriate input signals. Finally, one of these phosphodiesterases, PdeL, was studied in more detail. We demonstrated that this protein acts as a transcription factor to control its own expression. Motile suppressor alleles led to a strong increase of PdeL activity and elevated pdeL transcription, suggesting that enzymatic activity and transcriptional control are coupled. In agreement with this, we showed that overall cellular levels of c-di-GMP control pdeL transcription and that this control depends on PdeL itself. We thus propose that PdeL acts both as an enzyme and as a c-di-GMP sensor to couple transcriptional activity to the c-di-GMP status of the cell. IMPORTANCE Most bacteria possess multiple diguanylate cyclases and phosphodiesterases. Genetic studies have proposed that these enzymes show signaling specificity by contributing to distinct cellular processes without much cross talk. Thus, spatial

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

    Kruuse, Christina; Rybalkin, S D; Khurana, T S; Jansen-Olesen, I; Olesen, J.; Edvinsson, L

    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......M) pretreatment, indicating 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....

  12. Effects of metal ions and disulfide bonds on the activity of phosphodiesterase from Trimeresurus stejnegeri venom.

    Peng, Lili; Xu, Xiaolong; Guo, Mingchun; Yan, Xincheng; Wang, Shasha; Gao, Shang; Zhu, Shanshan

    2013-06-01

    Obviously different from the other known phosphodiesterases, the phosphodiesterase from Trimeresurus stejnegeri venom (TS-PDE) consists of two different chains linked with disulfide bonds and contains both endogenous Cu(2+) and Zn(2+). Cu(2+) and Zn(2+) are important for its phosphodiesterase activity. In this study, the effects of metal ions and small-molecule reductants on its structure and activity have been investigated by polyacrylamide gel electrophoresis, high performance liquid chromatography, fluorescence and electron paramagnetic resonance spectroscopy. The results show that TS-PDE has one class of Zn(2+) binding site and two classes of Cu(2+) binding site, including the high affinity activator sites and the low affinity sites. Cu(2+) ions function as a switch for its phosphodiesterase activity. The catalytic activity of TS-PDE does not have an absolute requirement for Cu(2+) and Zn(2+). Mg(2+), Mn(2+), Ni(2+), Co(2+) and Ca(2+) are all effective for its phosphodiesterase activity. TS-PDE has seven disulfide bonds and ten free cysteine residues. l-Ascorbate inhibits the phosphodiesterase activity of TS-PDE through reduction of the Cu(2+), while dithiothreitol, glutathione and tris(2-carboxyethyl)phosphine inhibit the phosphodiesterase activity of TS-PDE by reducing both the Cu(2+) and disulfide bonds. The catalytic activity of TS-PDE relies on its disulfide bonds and bimetallic cluster. In addition, biologically-relevant reductants, glutathione and l-ascorbate, have been found to be endogenous inhibitors to the phosphodiesterase activity of TS-PDE. PMID:23775423

  13. Novel phosphodiesterase-5 inhibitors: Current indications and future directions

    Sharma Rashmi

    2007-12-01

    Full Text Available Cardiovascular diseases like hypertension, hyperlipidemia, diabetes mellitus and obesity are the important predictors of erectile dysfunction (ED. Endothelial dysfunction is proposed to be the underlying cause of ED, just like coronary artery disease. Sildenafil was originally developed to treat angina pectoris but later on was recognized as novel treatment option for impotence. To date, sildenafil has been the most extensively studied PDE (phosphodiesterase-5 inhibitor. Currently two more PDE-5 inhibitors, tadalafil and vardenafil, are under study. Newer compounds have certain advantages over sildenafil, including greater selectivity for PDE-5 compared with other isoenzymes, absence of effect of food on absorption, faster onset and longer duration of action. PDE-5 inhibitors are emerging as novel therapeutic tools with a potential to protect or enhance endothelial function in humans and to selectively improve regional blood flow. The FDA has recently approved a reformulation of sildenafil for the treatment of pulmonary arterial hypertension. Raynaud′s phenomenon, respiratory disorders with ventilation/ perfusion mismatch, congestive cardiac failure, hypertension and stroke are the other conditions in which PDE-5 inhibitors are being tried. It is hoped that this group of drugs will soon emerge as a novel weapon in the armamentarium against various cardiovascular and pulmonary diseases.

  14. Tadalafil: a phosphodiesterase-5 inhibitor for benign prostatic hyperplasia.

    Cantrell, Matthew A; Baye, Jordan; Vouri, Scott Martin

    2013-06-01

    Tadalafil is a phosphodiesterase (PDE)-5 inhibitor recently approved by the United States Food and Drug Administration for lower urinary tracts symptoms (LUTS) associated with benign prostatic hyperplasia (BPH). The mechanism for improved LUTS is thought to be related to three principal theories: alterations in nitric oxide levels, Rho-associated protein kinase deactivation, and reductions in pelvic atherosclerosis. The efficacy of PDE-5 inhibitors for the treatment of LUTS associated with BPH has been demonstrated in several randomized placebo-controlled trials. Tadalafil is thought to be superior based on an extended half-life; however, other PDE-5 inhibitors have positive results in BPH and have not been proved to be inferior to tadalafil. Before administration, concomitant use of medications such as nonselective α-adrenergic antagonists, nitrates, and cytochrome P450 inhibitors should be assessed for possible drug interactions. Potential adverse drug events seen in Food and Drug Administration-approved tadalafil include back pain, dyspepsia, headache, and dizziness. Given the efficacy and safety data currently available, the PDE-5 inhibitor tadalafil represents a reasonable alternative for selected male patients with LUTS associated with BPH, especially with concomitant erectile dysfunction. PMID:23529917

  15. Role of Phosphodiesterase 5 and Cyclic GMP in Hypertension.

    Mergia, Evanthia; Stegbauer, Johannes

    2016-04-01

    Cyclic GMP (cGMP) is a ubiquitous intracellular second messenger that mediates a wide spectrum of physiologic processes in multiple cell types within the cardiovascular and nervous systems. Synthesis of cGMP occurs either by NO-sensitive guanylyl cyclases in response to nitric oxide or by membrane-bound guanylyl cyclases in response to natriuretic peptides and has been shown to regulate blood pressure homeostasis by influencing vascular tone, sympathetic nervous system, and sodium and water handling in the kidney. Several cGMPs degrading phosphodiesterases (PDEs), including PDE1 and PDE5, play an important role in the regulation of cGMP signaling. Recent findings revealed that increased activity of cGMP-hydrolyzing PDEs contribute to the development of hypertension. In this review, we will summarize recent research findings regarding the cGMP/PDE signaling in the vasculature, the central nervous system, and the kidney which are associated with the development and maintenance of hypertension. PMID:27079836

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

    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

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

    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.

  18. Cyclic AMP phosphodiesterase in Salmonella typhimurium: characteristics and physiological function.

    Botsford, J L

    1984-11-01

    The physiological function of cyclic AMP (cAMP) phosphodiesterase in Salmonella typhimurium was investigated with strains which were isogenic except for the cpd locus. In crude broken-cell extracts the properties of the enzyme were found to be similar to those reported for Escherichia coli. The specific activity in the mutant was less than 1% that in the wild type. Rates of cAMP production in the mutant were as much as twice those observed in the wild type. The amount of cAMP accumulated when cells grew overnight with limiting glucose was 4.5-fold greater in the mutant than in the wild type. The intracellular concentration of cAMP in the two strains was measured directly, using four different techniques to wash the cells to remove extracellular cAMP. The cAMP level in the cpd strain was only 25% greater than in the wild type. The functional concentration of the cAMP receptor protein-cAMP complex was estimated indirectly from the specific activity of beta-galactosidase in the two strains after introducing F'lac. When cells were grown with carbon sources permitting synthesis of different levels of cAMP, the specific activity of the enzyme was at most 25% greater in the cpd strain. The cpd strain was more sensitive to the effects of exogenous cAMP. Exogenous cAMP relieved both permanent and transient catabolite repression of the lac operon at lower concentrations in the cpd strain than in the wild type. When cells grew with glucose, glycerol, or ribose, exogenous cAMP inhibited growth of the mutant strain more than the wild type. PMID:6094495

  19. The Wonders of Phosphodiesterase-5 Inhibitors: A Majestic History.

    Elhwuegi, A S

    2016-01-01

    The Nobel Prize winning discovery of nitric oxide (NO) in 1986 was the starting point for a new innovation in drug discovery. NO acting as a mediator at different physiological systems is believed to be involved in many physiological and pathological conditions through the formation of the second messenger cyclic guanosine monophosphate (cGMP). cGMP-dependent vasodilation effect of NO is important in regulating pulmonary and systemic pressures, maintaining penis erection, preventing atherosclerosis, preventing platelet aggregation, and protecting and controlling cardiac functions. The main enzyme involved in the termination of cGMP effects is phosphodiesterase enzyme 5 (PDE-5), which is overexpressed in ventricular hypertrophy and heart failure. A milestone in drug discovery was the selective inhibitors of PDE-5 that developed to be a multibillion dollar blockbuster in drug market. PDE-5 inhibitors are approved for the treatment of erectile dysfunctions (EDs), pulmonary hypertension, and benign prostatic hypertrophy. They are also under clinical trials for their cardiac protection against damage induced by ischemia or heart failure. This review article is an update about the pharmacotherapeutics of PDE-5 inhibitors and the majestic history that led to their discovery. The information reported in this review was obtained from the electronic sources of different databases such as PubMed Central, Google Scholar, and Scopus. Keywords used for search included cGMP (mechanisms and functions), EDs (drugs used), nitric oxide, and PDE-5 inhibitors (clinical applications). A total of 165 articles were studied, of which 45 articles were referred to in this review. PMID:27398244

  20. Phosphodiesterase 4D gene polymorphisms in sudden sensorineural hearing loss.

    Chien, Chen-Yu; Tai, Shu-Yu; Wang, Ling-Feng; Hsi, Edward; Chang, Ning-Chia; Wang, Hsun-Mo; Wu, Ming-Tsang; Ho, Kuen-Yao

    2016-09-01

    The phosphodiesterase 4D (PDE4D) gene has been reported as a risk gene for ischemic stroke. The vascular factors are between the hypothesized etiologies of sudden sensorineural hearing loss (SSNHL), and this genetic effect might be attributed for its role in SSNHL. We hypothesized that genetic variants of the PDE4D gene are associated with susceptibility to SSNHL. We conducted a case-control study with 362 SSNHL cases and 209 controls. Three single nucleotide polymorphisms (SNPs) were selected. The genotypes were determined using TaqMan technology. Hardy-Weinberg equilibrium (HWE) was tested for each SNP, and genetic effects were evaluated according to three inheritance modes. We carried out sex-specific analysis to analyze the overall data. All three SNPs were in HWE. When subjects were stratified by sex, the genetic effect was only evident in females but not in males. The TT genotype of rs702553 exhibited an adjusted odds ratio (OR) of 3.83 (95 % confidence interval = 1.46-11.18) (p = 0.006) in female SSNHL. The TT genotype of SNP rs702553 was associated with female SSNHL under the recessive model (p = 0.004, OR 3.70). In multivariate logistic regression analysis, TT genotype of rs702553 was significantly associated with female SSNHL (p = 0.0043, OR 3.70). These results suggest that PDE4D gene polymorphisms influence the susceptibility for the development of SSNHL in the southern Taiwanese female population. PMID:26521189

  1. Phosphodiesterase 10A upregulation contributes to pulmonary vascular remodeling.

    Tian, Xia; Vroom, Christina; Ghofrani, Hossein Ardeschir; Weissmann, Norbert; Bieniek, Ewa; Grimminger, Friedrich; Seeger, Werner; Schermuly, Ralph Theo; Pullamsetti, Soni Savai

    2011-01-01

    Phosphodiesterases (PDEs) modulate the cellular proliferation involved in the pathophysiology of pulmonary hypertension (PH) by hydrolyzing cAMP and cGMP. The present study was designed to determine whether any of the recently identified PDEs (PDE7-PDE11) contribute to progressive pulmonary vascular remodeling in PH. All in vitro experiments were performed with lung tissue or pulmonary arterial smooth muscle cells (PASMCs) obtained from control rats or monocrotaline (MCT)-induced pulmonary hypertensive (MCT-PH) rats, and we examined the effects of the PDE10 inhibitor papaverine (Pap) and specific small interfering RNA (siRNA). In addition, papaverine was administrated to MCT-induced PH rats from day 21 to day 35 by continuous intravenous infusion to examine the in vivo effects of PDE10A inhibition. We found that PDE10A was predominantly present in the lung vasculature, and the mRNA, protein, and activity levels of PDE10A were all significantly increased in MCT PASMCs compared with control PASMCs. Papaverine and PDE10A siRNA induced an accumulation of intracellular cAMP, activated cAMP response element binding protein and attenuated PASMC proliferation. Intravenous infusion of papaverine in MCT-PH rats resulted in a 40%-50% attenuation of the effects on pulmonary hypertensive hemodynamic parameters and pulmonary vascular remodeling. The present study is the first to demonstrate a central role of PDE10A in progressive pulmonary vascular remodeling, and the results suggest a novel therapeutic approach for the treatment of PH. PMID:21494592

  2. Counterfeit phosphodiesterase type 5 inhibitors pose significant safety risks.

    Jackson, G; Arver, S; Banks, I; Stecher, V J

    2010-03-01

    Counterfeit drugs are inherently dangerous and a growing problem; counterfeiters are becoming increasingly sophisticated. Growth of the counterfeit medication market is attributable in part to phosphodiesterase type 5 inhibitor (PDE5i) medications for erectile dysfunction (ED). Millions of counterfeit PDE5is are seized yearly and account for the bulk of all counterfeit pharmaceutical product seizures. It has been estimated that up to 2.5 million men in Europe are exposed to illicit sildenafil, suggesting that there may be as many illegal as legal users of sildenafil. Analysis of the contents of counterfeit PDE5is shows inconsistent doses of active pharmaceutical ingredients (from 0% to > 200% of labelled dose), contaminants (including talcum powder, commercial paint and printer ink) and alternative ingredients that are potentially hazardous. In one analysis, only 10.1% of samples were within 10% of the labelled tablet strength. Estimates place the proportion of counterfeit medications sold over the Internet from 44% to 90%. Of men who purchase prescription-only medication for ED without a prescription, 67% do so using the Internet. Counterfeit PDE5is pose direct and indirect risks to health, including circumvention of the healthcare system. More than 30% of men reported no healthcare interaction when purchasing ED medications. Because > 65% actually had ED, these men missed an opportunity for evaluation of comorbidities (e.g. diabetes and hypertension). Globally, increased obstacles for counterfeiters are necessary to combat pharmaceutical counterfeiting, including fines and penalties. The worldwide nature of the counterfeit problem requires proper coordination between countries to ensure adequate enforcement. Locally, physicians who treat ED need to inform patients of the dangers of ordering PDE5is via the Internet. PMID:20088883

  3. AB030. Evolution of phosphodiesterase type 5 inhibitors

    Moon, Du Geon

    2016-01-01

    After launching of sildenafil citrate, the last invention of 20th century, in 1998, oral phosphodiesterase type 5 (PDE5) inhibitor has been established as first line treatment of erectile dysfunction and shift new paradigm of diagnosis and treatment of erectile dysfunction. The big success of sildenafil in pharmaceutical R&D induced the consecutive development of the so-called ‘The second Viagra’, e.g., tadalafil and vardenafil in 2003. Currently, these 3 kinds of PDE5 inhibitors are most famous and well-known PDE5 inhibitors worldwide. From the early competition, PDE5 inhibitors have been continuously evolved through completion for survival. In Korea, another 3 kinds of PDE5 inhibitors, udenafil [2005], mirodenafil [2007] and avanafil [2011] have been developed. Additionally 60 generic sildenafils from 49 companies were released with termination of sildenafil patent in Korea, 2012 and 160 generic tadalafils from 64 companies were released with termination of tadalafil patent in Korea, 2015. Besides of Korea PDE5I, generic sildenafil and generic tadalafil induce cheaper PDE5I, as much as 1/5 of original PDE5Is. The dosage concept also evolved from on-demand to daily low-dose and alternative dosage. These changes of dosage concept was proved from safety of daily use and indication of PDE5Is for ED also evolved beyond ED and widened to pulmonary hypertension of Sildenafil, benign prostatic hyperplasia (BPH)/lower urinary tract symptoms (LUTS) of tadalafil and penile rehabilitation after RRP. For the launching of Generic PDE5Is, the preparation also evolved from tablet to orodisposable film, granule and chewable. The orodisposable film and chewable is favorable from patients. In Korea, the impact of recent generic tadalafil is totally different from those of generic Sildenafil in 2012. The long half-life of tadalafil enabled the approval for BPH/LUTS with daily low dose usage. In turn, the generic Cialis also will be developed as various preparations including

  4. 2'-phosphodiesterase and 2',5'-oligoadenylate synthetase activities in the lowest metazoans, sponge [porifera

    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...

  5. Phosphodiesterase type 5 inhibitors in the treatment of pulmonary arterial hypertension

    Kadriye Kılıçkesmez; M. Serdar Küçükoğlu

    2010-01-01

    The pathology of pulmonary arterial hypertension (PAH) is characterized by vascular vasoconstriction, smooth muscle cell proliferation, and thrombosis. Experimental studies have shown the beneficial effect of phosphodiesterase type 5 (PDE-5) inhibitors on pulmonary vascular remodeling and vasodilatation. Randomized clinical trials in monotherapy or combination therapy have been conducted in PAH with sildenafil and tadalafil which significantly improve clinical status, exercise capacity and he...

  6. Clinical effects of phosphodiesterase 3A mutations in inherited hypertension with brachydactyly.

    Toka, Okan; Tank, Jens; Schächterle, Carolin; Aydin, Atakan; Maass, Philipp G; Elitok, Saban; Bartels-Klein, Eireen; Hollfinger, Irene; Lindschau, Carsten; Mai, Knut; Boschmann, Michael; Rahn, Gabriele; Movsesian, Matthew A; Müller, Thomas; Doescher, Andrea; Gnoth, Simone; Mühl, Astrid; Toka, Hakan R; Wefeld-Neuenfeld, Yvette; Utz, Wolfgang; Töpper, Agnieszka; Jordan, Jens; Schulz-Menger, Jeanette; Klussmann, Enno; Bähring, Sylvia; Luft, Friedrich C

    2015-10-01

    Autosomal-dominant hypertension with brachydactyly is a salt-independent Mendelian syndrome caused by activating mutations in the gene encoding phosphodiesterase 3A. These mutations increase the protein kinase A-mediated phosphorylation of phosphodiesterase 3A resulting in enhanced cAMP-hydrolytic affinity and accelerated cell proliferation. The phosphorylated vasodilator-stimulated phosphoprotein is diminished, and parathyroid hormone-related peptide is dysregulated, potentially accounting for all phenotypic features. Untreated patients die prematurely of stroke; however, hypertension-induced target-organ damage is otherwise hardly apparent. We conducted clinical studies of vascular function, cardiac functional imaging, platelet function in affected and nonaffected persons, and cell-based assays. Large-vessel and cardiac functions indeed seem to be preserved. The platelet studies showed normal platelet function. Cell-based studies demonstrated that available phosphodiesterase 3A inhibitors suppress the mutant isoforms. However, increasing cGMP to indirectly inhibit the enzyme seemed to have particular use. Our results shed more light on phosphodiesterase 3A activation and could be relevant to the treatment of severe hypertension in the general population. PMID:26283042

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

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

    2002-01-01

    We tested the hypothesis that cGMP stimulates renin release through inhibition of the cAMP-specific phosphodiesterase 3 (PDE3) in isolated rat juxtaglomerular (JG) cells. In addition, we assessed the involvement of PDE4 in JG-cell function. JG cells expressed PDE3A and PDE3B, and the PDE3 inhibit...

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

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

  9. The role of phosphodiesterase inhibitors in the management of pulmonary vascular diseases

    Butrous, Ghazwan

    2014-01-01

    Phosphodiesterase inhibitors (PDE) can be used as therapeutic agents for various diseases such as dementia, depression, schizophrenia and erectile dysfunction in men, as well as congestive heart failure, chronic obstructive pulmonary disease, rheumatoid arthritis, other inflammatory diseases, diabetes and various other conditions. In this review we will concentrate on one type of PDE, mainly PDE5 and its role in pulmonary vascular diseases.

  10. Genetic locus (stmF) associated with cyclic GMP phosphodiesterase activity in Dictyostelium discoideum maps in linkage group II.

    Coukell, M. B.; Cameron, A M

    1985-01-01

    Previous attempts to map the stmF locus in Dictyostelium discoideum, by using only clone morphology as a marker, have led to equivocal results. Since strains carrying mutations at the stmF locus possess very low cyclic GMP phosphodiesterase activity, we have remapped this locus using both morphological and biochemical markers. Our results indicate that mutations producing a stable "streamer" phenotype and reduced cyclic GMP phosphodiesterase activity are located in linkage group II, probably ...

  11. The Internal Phosphodiesterase RegA Is Essential for the Suppression of Lateral Pseudopods during Dictyostelium Chemotaxis

    Wessels, Deborah J.; Zhang, Hui; Reynolds, Joshua; Daniels, Karla; Heid, Paul; Lu, Sijie; Kuspa, Adam; Shaulsky, Gad; Loomis, William F.; Soll, David R.

    2000-01-01

    Dictyostelium strains in which the gene encoding the cytoplasmic cAMP phosphodiesterase RegA is inactivated form small aggregates. This defect was corrected by introducing copies of the wild-type regA gene, indicating that the defect was solely the consequence of the loss of the phosphodiesterase. Using a computer-assisted motion analysis system, regA− mutant cells were found to show little sense of direction during aggregation. When labeled wild-type cells wer...

  12. Significance of salivary phosphodiesterase level in oral squamous cell carcinoma patients

    Yousef Rezaei Chianeh; Krishnananda Prabhu; Rashmi M.; Donald J. Fernandes

    2013-01-01

    Oral cancer, more specifically oral squamous cell carcinoma (OSCC) consider as common cancer that 300,000 people diagnosed per year worldwide. The only effective treatment for OSCC is surgical intervention. Over the past two decades, overall disease condition has not improved although advancement of treatment has considerably increased. The phosphodiesterase (PDEs) are responsible for the hydrolysis of the second messengers with a fundamental role in the transduction of the intracellular sign...

  13. Type 5 phosphodiesterase expression is a critical determinant of the endothelial cell angiogenic phenotype

    Zhu, Bing; Zhang, Li; Alexeyev, Mikhail; Alvarez, Diego F.; Strada, Samuel J.; Stevens, Troy

    2008-01-01

    Type 5 phosphodiesterase (PDE5) inhibitors increase endothelial cell cGMP and promote angiogenesis. However, not all endothelial cell phenotypes express PDE5. Indeed, whereas conduit endothelial cells express PDE5, microvascular endothelial cells do not express this enzyme, and they are rapidly angiogenic. These findings bring into question whether PDE5 activity is a critical determinant of the endothelial cell angiogenic potential. To address this question, human full-length PDE5A1 was stabl...

  14. Erectile dysfunction and heart failure: the role of phosphodiesterase type 5 inhibitors

    Al-Ameri, H; Kloner, R. A.

    2009-01-01

    The phosphodiesterase type 5 (PDE-5) inhibitors are effective in treating erectile dysfunction (ED). ED and heart failure (HF) share similar risk factors, and commonly present together. This association has led to questions ranging from the safety and efficacy of PDE-5 inhibitors in HF patients to a possible role for this class of medication to treat HF patients with or without ED. In addition to endothelial dysfunction, there are causes of ED specific to patients with HF including low exerci...

  15. Phosphodiesterase type 5 inhibitors as a treatment for erectile dysfunction: Current information and new horizons

    Ferguson, James E.; Carson, Culley C

    2013-01-01

    Introduction Over the past 15 years, the discovery and development of oral medications that selectively inhibit the enzyme phosphodiesterase type 5 (PDE5) have revolutionised the treatment of erectile dysfunction (ED). Currently, three PDE5 inhibitors are widely available clinically, i.e., sildenafil, vardenafil and tadalafil. New PDE5 inhibitors, including avanafil and udenafil, are now in clinical use in a few countries, and other compounds are under development. Methods We describe the cur...

  16. Chronic Low Dosing of Phosphodiesterase Type 5 Inhibitor for Erectile Dysfunction

    Sung, Hyun Hwan; Lee, Sung Won

    2012-01-01

    Oral phosphodiesterase type 5 (PDE5) inhibitors have provided non-invasive, effective, and well-tolerated treatments for patients with erectile dysfunction (ED). However, many patients with ED are unresponsive to 'on-demand' PDE5 inhibitors. In addition, the lack of spontaneity and naturalness of the on-demand regimen could be a reason for decreased compliance with PDE5 inhibitors. Recently, tadalafil and udenafil were approved for low-dose daily administration for the treatment of ED. Since ...

  17. Development of Radiolabeled PET Tracers for In Vivo Visualization of Phosphodiesterase Type 5 (PDE5)

    Chekol, Rufael Senetsehay

    2014-01-01

    Phosphodiesterase type 5 (PDE5) is highly expressed in vascular smooth muscle cells, and its inhibition is a primary target for the treatment of erectile dysfunction and pulmonary hypertension. Besides, PDE5 plays a pivotal role in disease progressions such as, cardiac hypertrophy and ventricular remodeling, myocardial ischemia, aortic stenosis, end stage congestive heart failure and atherosclerosis. Several PDE5 inhibitors are approved for clinical use or have been introduced in preclinical ...

  18. Inhibition of phosphodiesterase 5 reduces bone mass by suppression of canonical Wnt signaling

    Gong, Y.; C. Y. Xu; Wang, J. R.; Hu, X. H.; Hong, D; X. Ji; Shi, W; Chen, H. X.; Wang, H. B.; X. M. Wu

    2014-01-01

    Inhibitors of phosphodiesterase 5 (PDE5) are widely used to treat erectile dysfunction and pulmonary hypertension in clinics. PDE5, cyclic guanosine monophosphate (cGMP), and protein kinase G (PKG) are important components of the non-canonical Wnt signaling. This study aimed to investigate the effect of PDE5 inhibition on canonical Wnt signaling and osteoblastogenesis, using both in vitro cell culture and in vivo animal models. In the in vitro experiments, PDE5 inhibition resulted in activati...

  19. An insight into the pharmacophores of phosphodiesterase-5 inhibitors from synthetic and crystal structural studies

    Chen, Gong; Wang, Huanchen; Robinson, Howard; Cai, Jiwen; Wan, Yiqian; Ke, Hengming

    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)...

  20. Phosphodiesterase 5 Inhibitors Enhance Chemotherapy Killing in Gastrointestinal/Genitourinary Cancer Cells

    Booth, Laurence; ROBERTS, JANE L.; Cruickshanks, Nichola; Conley, Adam; Durrant, David E.; Das, Anindita; Fisher, Paul B.; Kukreja, Rakesh C.; Grant, Steven; Poklepovic, Andrew; Dent, Paul

    2014-01-01

    The present studies determined whether clinically relevant phosphodiesterase 5 (PDE5) inhibitors interacted with clinically relevant chemotherapies to kill gastrointestinal/genitourinary cancer cells. In bladder cancer cells, regardless of H-RAS mutational status, at clinically achievable doses, PDE5 inhibitors interacted in a greater than additive fashion with doxorubicin/mitomycin C/gemcitabine/cisplatin/paclitaxel to cause cell death. In pancreatic tumor cells expressing mutant active K-RA...

  1. Usage and perceptions of phosphodiesterase type 5 inhibitors among the male partners of infertile couples

    Song, Seung-Hun; Kim, Dong Suk; Shim, Sung Han; Lim, Jung Jin; Yang, Seung Choul

    2016-01-01

    Objective We aimed to investigate the prevalence of erectile dysfunction (ED) and the usage of phosphodiesterase type 5 (PDE5) inhibitors for ED treatment in infertile couples. Methods A total of 260 male partners in couples reporting infertility lasting at least 1 year were included in this study. In addition to an evaluation of infertility, all participants completed the International Index of Erectile Function (IIEF)-5 questionnaire to evaluate their sexual function. The participants were ...

  2. Non-invasive management of primary phosphodiesterase type 5 inhibitor failure in patients with erectile dysfunction

    Lowe, Gregory; Bahnson, Robert

    2009-01-01

    Phosphodiesterase type 5 inhibitors (PDE5-i) have become first line therapy for the treatment of erectile dysfunction. Most initial prescriptions for PDE5-i are by primary care practitioners. Urologists must now routinely manage the patient who has failed initial therapy with PDE5-i. Lifestyle modifications can be of benefit to patients. Patient education and optimization of the PDE5-i can result in a successful response. Interestingly, there are reports of up to 60% salvage after changing th...

  3. Molecular cloning and characterization of a calmodulin-dependent phosphodiesterase enriched in olfactory sensory neurons.

    C. Yan; Zhao, A Z; Bentley, J K; Loughney, K; Ferguson, K; Beavo, J. A.

    1995-01-01

    The sensing of an odorant by an animal must be a rapid but transient process, requiring an instant response and also a speedy termination of the signal. Previous biochemical and electrophysiological studies suggest that one or more phosphodiesterases (PDEs) may play an essential role in the rapid termination of the odorant-induced cAMP signal. Here we report the molecular cloning, expression, and characterization of a cDNA from rat olfactory epithelium that encodes a member of the calmodulin-...

  4. Phosphodiesterase 10A Regulates Alcohol and Saccharin Self-Administration in Rats

    Logrip, Marian L.; Leandro F Vendruscolo; Schlosburg, Joel E.; Koob, George F.; Zorrilla, Eric P.

    2014-01-01

    A history of stress produces increases in rodent relapse-like alcohol self-administration behavior and regional brain gene expression of phosphodiesterase 10A (PDE10A), a dual-specificity cyclic adenosine monophosphate/cyclic guanosine monophosphate-inhibiting enzyme. Here, we tested the hypothesis that administration of TP-10, a specific PDE10A inhibitor, would reduce alcohol self-administration in conditions predisposing to elevated self-administration. TP-10 administration dose-dependently...

  5. Phosphodiesterase 8B gene polymorphism in women with recurrent miscarriage: A retrospective case control study

    Granfors Michaela; Karypidis Helena; Hosseini Frida; Skjöldebrand-Sparre Lottie; Stavreus-Evers Anneli; Bremme Katarina; Landgren Britth-Marie; Sundström-Poromaa Inger; Wikström Anna-Karin; Åkerud Helena

    2012-01-01

    Abstract Background Recurrent miscarriage affects approximately 1% of all couples. There is a known relation between hypothyroidism and recurrent miscarriage. Phosphodiesterase 8B (PDE8B) is a regulator of cyclic adenosine monophosphate (cAMP) with important influence on human thyroid metabolism. Single nucleotide polymorphism (SNP) rs 4704397 in the PDE8B gene has been shown to be associated with variations in serum Thyroid Stimulating Hormone (TSH) and thyroxine (T4) levels. The aim of this...

  6. Alterations in regulation of energy homeostasis in cyclic nucleotide phosphodiesterase 3B–null mice

    Choi, Young Hun; Park, Sunhee; Hockman, Steven; Zmuda-Trzebiatowska, Emilia; Svennelid, Fredrik; Haluzik, Martin; Gavrilova, Oksana; Ahmad, Faiyaz; Pepin, Laurent; Napolitano, Maria; Taira, Masato; Sundler, Frank; Stenson Holst, Lena; Degerman, Eva; Manganiello, Vincent C.

    2006-01-01

    Cyclic nucleotide phosphodiesterase 3B (PDE3B) has been suggested to be critical for mediating insulin/IGF-1 inhibition of cAMP signaling in adipocytes, liver, and pancreatic β cells. In Pde3b-KO adipocytes we found decreased adipocyte size, unchanged insulin-stimulated phosphorylation of protein kinase B and activation of glucose uptake, enhanced catecholamine-stimulated lipolysis and insulin-stimulated lipogenesis, and blocked insulin inhibition of catecholamine-stimulated lipolysis. Glucos...

  7. Genomic and functional characterizations of phosphodiesterase subtype 4D in human cancers

    Lin, De-Chen; Xu, Liang; Ding, Ling-Wen; Sharma, Arjun; Liu, Li-Zhen; Yang, Henry; Tan, Patrick; Vadgama, Jay; Karlan, Beth Y.; Lester, Jenny; Urban, Nicole; Schummer, Michèl; Doan, Ngan; Said, Jonathan W.; Sun, Hongmao

    2013-01-01

    Discovery of cancer genes through interrogation of genomic dosage is one of the major approaches in cancer research. In this study, we report that phosphodiesterase subtype 4D (PDE4D) gene was homozygously deleted in 198 cases of 5,569 primary solid tumors (3.56%), with most being internal microdeletions. Unexpectedly, the microdeletions did not result in loss of their gene products. Screening PDE4D expression in 11 different types of primary tumor samples (n = 165) with immunohistochemistry ...

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

    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...

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

    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 32P-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 [3H]-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. N2-Hexyl-cGMP inhibits phosphodiesterase activity by competing with cGMP for hydrolysis at the catalytic site but not at the binding site. N2-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

  10. 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

    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

  11. Function and protective capacity of Treponema pallidum subsp. pallidum glycerophosphodiester phosphodiesterase.

    Cameron, C E; Castro, C; Lukehart, S A; Van Voorhis, W C

    1998-12-01

    Infectious syphilis, caused by the spirochete bacterium Treponema pallidum subsp. pallidum, remains a public health concern worldwide. The immune-response evasion mechanisms employed by T. pallidum are poorly understood, and prior attempts to identify immunoprotective antigens for subsequent vaccine design have been unsuccessful. Previous investigations conducted in our laboratory identified the T. pallidum glycerophosphodiester phosphodiesterase as a potential immunoprotective antigen by using a differential immunologic expression library screen. In studies reported here, heterologous expression of the T. pallidum glycerophosphodiester phosphodiesterase in Escherichia coli yielded a full-length, enzymatically active protein. Characterization of the recombinant molecule showed it to be bifunctional, in that it exhibited specific binding to human immunoglobulin A (IgA), IgD, and IgG in addition to possessing enzymatic activity. IgG fractionation studies revealed specific binding of the recombinant enzyme to the Fc fragment of human IgG, a characteristic that may play a role in enabling the syphilis spirochete to evade the host immune response. In further investigations, immunization with the recombinant enzyme significantly protected rabbits from subsequent T. pallidum challenge, altering lesion development at the sites of challenge. In all cases, animals immunized with the recombinant molecule developed atypical pale, flat, slightly indurated, and nonulcerative reactions at the challenge sites that resolved before lesions appeared in the control animals. Although protection in the immunized rabbits was incomplete, as demonstrated by the presence of T. pallidum in the rabbit infectivity test, glycerophosphodiester phosphodiesterase nevertheless represents a significantly immunoprotective T. pallidum antigen and thus may be useful for inclusion in an antigen cocktail vaccine for syphilis. PMID:9826352

  12. Specific Inhibition of Phosphodiesterase-4B Results in Anxiolysis and Facilitates Memory Acquisition.

    McGirr, Alexander; Lipina, Tatiana V; Mun, Ho-Suk; Georgiou, John; Al-Amri, Ahmed H; Ng, Enoch; Zhai, Dongxu; Elliott, Christina; Cameron, Ryan T; Mullins, Jonathan Gl; Liu, Fang; Baillie, George S; Clapcote, Steven J; Roder, John C

    2016-03-01

    Cognitive dysfunction is a core feature of dementia and a prominent feature in psychiatric disease. As non-redundant regulators of intracellular cAMP gradients, phosphodiesterases (PDE) mediate fundamental aspects of brain function relevant to learning, memory, and higher cognitive functions. Phosphodiesterase-4B (PDE4B) is an important phosphodiesterase in the hippocampal formation, is a major Disrupted in Schizophrenia 1 (DISC1) binding partner and is itself a risk gene for psychiatric illness. To define the effects of specific inhibition of the PDE4B subtype, we generated mice with a catalytic domain mutant form of PDE4B (Y358C) that has decreased ability to hydrolyze cAMP. Structural modeling predictions of decreased function and impaired binding with DISC1 were confirmed in cell assays. Phenotypic characterization of the PDE4B(Y358C) mice revealed facilitated phosphorylation of CREB, decreased binding to DISC1, and upregulation of DISC1 and β-Arrestin in hippocampus and amygdala. In behavioral assays, PDE4B(Y358C) mice displayed decreased anxiety and increased exploration, as well as cognitive enhancement across several tests of learning and memory, consistent with synaptic changes including enhanced long-term potentiation and impaired depotentiation ex vivo. PDE4B(Y358C) mice also demonstrated enhanced neurogenesis. Contextual fear memory, though intact at 24 h, was decreased at 7 days in PDE4B(Y358C) mice, an effect replicated pharmacologically with a non-selective PDE4 inhibitor, implicating cAMP signaling by PDE4B in a very late phase of consolidation. No effect of the PDE4B(Y358C) mutation was observed in the prepulse inhibition and forced swim tests. Our data establish specific inhibition of PDE4B as a promising therapeutic approach for disorders of cognition and anxiety, and a putative target for pathological fear memory. PMID:26272049

  13. Future options for disease intervention: important advances in phosphodiesterase 4 inhibitors

    R. A. McIvor

    2007-09-01

    Full Text Available Current drug treatments for chronic obstructive pulmonary disease (COPD focus on managing symptoms of the disease and include short- and long-acting beta2-agonists, anticholinergic agents (ipratroprium, tiotropium, methylxanthines (theophylline and inhaled corticosteroids (ICS. Cyclic nucleotide phosphodiesterases (PDEs play a key role in cell signalling by degrading cyclic adenosine monophosphate (cAMP and cyclic guanosine monophosphate. PDE4 is expressed in inflammatory cells and inhibition of this enzyme enhances the anti-inflammatory effects of cAMP in all key cells involved in COPD. Two PDE4 inhibitors, roflumilast and cilomilast, have been extensively evaluated in patients with COPD. Results from patients with moderate-to-severe and severe-to-very severe COPD have shown that roflumilast significantly improves forced expiratory volume in one second (FEV1 and significantly decreases exacerbations, particularly in patients with severe disease. Roflumilast is well tolerated with a low incidence of gastrointestinal adverse events that declines with continued treatment. Clinical trials with cilomilast have produced more varied results. Significant improvements in FEV1 and reductions in exacerbation rates versus placebo were observed in two of four trials. Cilomilast also has a high risk for gastrointestinal adverse events that does not appear to dissipate over 24 weeks of treatment. While further research is needed to fully determine the place in chronic obstructive pulmonary disease therapy for phosphodiesterase 4 inhibitors, they have several important potential benefits in the treatment of this disease, including convenient once-daily oral administration and freedom from adverse effects associated with corticosteroids. The fact that phosphodiesterase 4 inhibitors have potent anti-inflammatory effects and are administered orally, thereby reaching the systemic circulation, may decrease the severity of systemic comorbidities in chronic

  14. Cyclic GMP-specific Phosphodiesterase-5 Regulates Motility of Sea Urchin Spermatozoa

    Su, Yi-Hsien; Vacquier, Victor D.

    2006-01-01

    Motility, chemotaxis, and the acrosome reaction of animal sperm are all regulated by cyclic nucleotides and protein phosphorylation. One of the cyclic AMP-dependent protein kinase (PKA) substrates in sea urchin sperm is a member of the phosphodiesterase (PDE) family. The molecular identity and in vivo function of this PDE remained unknown. Here we cloned and characterized this sea urchin sperm PDE (suPDE5), which is an ortholog of human PDE5. The recombinant catalytic domain of suPDE5 hydroly...

  15. Phosphodiesterase-5 expression and function in the lower urinary tract: a critical review.

    Lin, Ching-Shwun; Albersen, Maarten; Xin, Zhongcheng; Namiki, Mikio; Muller, Dieter; Lue, Tom F

    2013-03-01

    Both clinical and preclinical studies have mostly shown beneficial effects for Phosphodiesterase-5 (PDE-5) inhibitors in the treatment of lower urinary tract symptoms. Molecular studies have consistently shown abundant PDE-5 expression in bladder smooth muscle. Data concerning urethral PDE-5 expression have been surprising because striated muscle was not only positively identified, but also found to express more PDE-5 than the smooth muscle. In the prostate, highly variable results have been obtained. For PDE-5 expression, the data have ranged from extremely low to highly abundant. PDE-5 has been found in the glandular epithelium, vascular smooth muscle, endothelium, and fibromuscular stroma. PMID:23333001

  16. Phosphodiesterase-5 (PDE5) is a Therapeutic Target for Peripheral Neuropathy in Diabetic Mice

    Wang, Lei; Chopp, Michael; Szalad, Alexandra; Liu, Zhongwu; Bolz, Marianne; Ãlvarez, Francisco Moniche; Lu, Mei; Zhang, Li; Cui, Yisheng; Zhang, Rui Lan; Zhang, Zheng Gang

    2011-01-01

    Peripheral neuropathy is a common and major complication of diabetes, the underlying mechanisms of which are not fully understood. Using a mouse model of type II diabetes, the present study investigated the role of phosphodiesterase-5 (PDE5) in peripheral neuropathy. BKS.Cg-m+/+Leprdb/J (db/db) mice were treated with sildenafil, a specific inhibitor of PDE5, at doses of 2 and 10 mg/kg or saline. Levels of PDE5 and morphometric parameters in sciatic nerve tissue as well as the motor and sensor...

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

    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)

  18. Significance of salivary phosphodiesterase level in oral squamous cell carcinoma patients

    Yousef Rezaei Chianeh

    2013-08-01

    Full Text Available Oral cancer, more specifically oral squamous cell carcinoma (OSCC consider as common cancer that 300,000 people diagnosed per year worldwide. The only effective treatment for OSCC is surgical intervention. Over the past two decades, overall disease condition has not improved although advancement of treatment has considerably increased. The phosphodiesterase (PDEs are responsible for the hydrolysis of the second messengers with a fundamental role in the transduction of the intracellular signals. In numerous pathological conditions such as cellular differentiation, apoptosis, and tumor invasivity the different PDF activity has been observed that shown role in pathophysiological mechanism. The role of PDEs as an intervention factor for activation of angiogenesis by influencing a tumor growth has been shown. The objective of this study was to estimate and compare salivary PDEs levels in healthy controls and biopsy-proven oral cancer patients before definitive therapy. Study was done in patients age between 25-65 years biopsy proven oral cancer patients and control group. After obtaining prior consent from biopsy-proven oral cancer patients (n=26 (before onset of any definitive treatment and age- and sex-matched healthy controls (n=29, salivary sample was collected for estimation of the activity of phosphodiesterases (PDEs. [Int J Res Med Sci 2013; 1(4.000: 417-420

  19. Phosphodiesterase-5 inhibitors have distinct effects on the hemodynamics of the liver

    Dunkern Torsten

    2009-09-01

    Full Text Available Abstract Background The NO - cGMP system plays a key role in the regulation of sinusoidal tonus and liver blood flow with phosphodiesterase-5 (PDE-5 terminating the dilatory action of cGMP. We, therefore, investigated the effects of PDE-5 inhibitors on hepatic and systemic hemodynamics in rats. Methods Hemodynamic parameters were monitored for 60 min. after intravenous injection of sildenafil and vardenafil [1, 10 and 100 μg/kg (sil1, sil10, sil100, var1, var10, var100] in anesthetized rats. Results Cardiac output and heart rate remained constant. After a short dip, mean arterial blood pressure again increased. Systemic vascular resistance transiently decreased slightly. Changes in hepatic hemodynamic parameters started after few minutes and continued for at least 60 min. Portal (var10 -31%, sil10 -34% and hepatic arterial resistance (var10 -30%, sil10 -32% decreased significantly (p Conclusion Low doses of phosphodiesterase-5 inhibitors have distinct effects on hepatic hemodynamic parameters. Their therapeutic use in portal hypertension should therefore be evaluated.

  20. ABCD of the phosphodiesterase family: interaction and differential activity in COPD

    David MG Halpin

    2008-08-01

    Full Text Available David MG HalpinRoyal Devon and Exeter Hospital, Exeter, EX2 5DW, UKAbstract: Phosphodiesterases (PDEs are important enzymes that hydrolyze the cyclic nucleotides adenosine 3′5′-cyclic monophosphate (cAMP and guanosine 3′5′-cyclic monophosphate (cGMP to their inactive 5′ monophosphates. They are highly conserved across species and as well as their role in signal termination, they also have a vital role in intra-cellular localization of cyclic nucleotide signaling and integration of the cyclic nucleotide pathways with other signaling pathways. Because of their pivotal role in intracellular signaling, they are now of considerable interest as therapeutic targets in a wide variety diseases, including COPD where PDE inhibitors may have bronchodilator, anti-inflammatory and pulmonary vasodilator actions. This review examines the diversity and cellular localization of the isoforms of PDE, the known and speculative relevance of this to the treatment of COPD, and the range of PDE inhibitors in development together with a discussion of their possible role in treating COPD.Keywords: COPD, phosphodiesterase, bronchodilator, anti-inflammatory, pulmonary vasodilator

  1. Inhibition of Phosphodiesterase-4 during Pneumococcal Pneumonia Reduces Inflammation and Lung Injury in Mice.

    Tavares, Luciana P; Garcia, Cristiana C; Vago, Juliana P; Queiroz-Junior, Celso M; Galvão, Izabela; David, Bruna A; Rachid, Milene A; Silva, Patrícia M R; Russo, Remo C; Teixeira, Mauro M; Sousa, Lirlândia P

    2016-07-01

    Pneumococcal pneumonia is a leading cause of mortality worldwide. The inflammatory response to bacteria is necessary to control infection, but it may also contribute to tissue damage. Phosphodiesterase-4 inhibitors, such as rolipram (ROL), effectively reduce inflammation. Here, we examined the impact of ROL in a pneumococcal pneumonia murine model. Mice were infected intranasally with 10(5)-10(6) CFU of Streptococcus pneumoniae, treated with ROL in a prophylactic or therapeutic schedule in combination, or not, with the antibiotic ceftriaxone. Inflammation and bacteria counts were assessed, and ex vivo phagocytosis assays were performed. ROL treatment during S. pneumoniae infection decreased neutrophil recruitment into lungs and airways and reduced lung injury. Prophylactic ROL treatment also decreased cytokine levels in the airways. Although modulation of inflammation by ROL ameliorated pneumonia, bacteria burden was not reduced. On the other hand, antibiotic therapy reduced bacteria without reducing neutrophil infiltration, cytokine level, or lung injury. Combined ROL and ceftriaxone treatment decreased lethality rates and was more efficient in reducing inflammation, by increasing proresolving protein annexin A1 (AnxA1) expression, and bacterial burden by enhancing phagocytosis. Lack of AnxA1 increased inflammation and lethality induced by pneumococcal infection. These data show that immunomodulatory effects of phosphodiesterase-4 inhibitors are useful during severe pneumococcal pneumonia and suggest their potential benefit as adjunctive therapy during infectious diseases. PMID:26677751

  2. Mode of action of DNA-competitive small molecule inhibitors of tyrosyl DNA phosphodiesterase 2.

    Hornyak, Peter; Askwith, Trevor; Walker, Sarah; Komulainen, Emilia; Paradowski, Michael; Pennicott, Lewis E; Bartlett, Edward J; Brissett, Nigel C; Raoof, Ali; Watson, Mandy; Jordan, Allan M; Ogilvie, Donald J; Ward, Simon E; Atack, John R; Pearl, Laurence H; Caldecott, Keith W; Oliver, Antony W

    2016-07-01

    Tyrosyl-DNA phosphodiesterase 2 (TDP2) is a 5'-tyrosyl DNA phosphodiesterase important for the repair of DNA adducts generated by non-productive (abortive) activity of topoisomerase II (TOP2). TDP2 facilitates therapeutic resistance to topoisomerase poisons, which are widely used in the treatment of a range of cancer types. Consequently, TDP2 is an interesting target for the development of small molecule inhibitors that could restore sensitivity to topoisomerase-directed therapies. Previous studies identified a class of deazaflavin-based molecules that showed inhibitory activity against TDP2 at therapeutically useful concentrations, but their mode of action was uncertain. We have confirmed that the deazaflavin series inhibits TDP2 enzyme activity in a fluorescence-based assay, suitable for high-throughput screen (HTS)-screening. We have gone on to determine crystal structures of these compounds bound to a 'humanized' form of murine TDP2. The structures reveal their novel mode of action as competitive ligands for the binding site of an incoming DNA substrate, and point the way to generating novel and potent inhibitors of TDP2. PMID:27099339

  3. Disruption of Cnp1 uncouples oligodendroglial functions in axonal support and myelination.

    Lappe-Siefke, Corinna; Goebbels, Sandra; Gravel, Michel; Nicksch, Eva; Lee, John; Braun, Peter E; Griffiths, Ian R; Nave, Klaus-Armin

    2003-03-01

    Myelination of axons by oligodendrocytes enables rapid impulse propagation in the central nervous system. But long-term interactions between axons and their myelin sheaths are poorly understood. Here we show that Cnp1, which encodes 2',3'-cyclic nucleotide phosphodiesterase in oligodendrocytes, is essential for axonal survival but not for myelin assembly. In the absence of glial cyclic nucleotide phosphodiesterase, mice developed axonal swellings and neurodegeneration throughout the brain, leading to hydrocephalus and premature death. But, in contrast to previously studied myelin mutants, the ultrastructure, periodicity and physical stability of myelin were not altered in these mice. Genetically, the chief function of glia in supporting axonal integrity can thus be completely uncoupled from its function in maintaining compact myelin. Oligodendrocyte dysfunction, such as that in multiple sclerosis lesions, may suffice to cause secondary axonal loss. PMID:12590258

  4. Cicaprost and the type IV phosphodiesterase inhibitor, rolipram, synergize in suppression of tumor necrosis factor-alpha synthesis

    Greten, T F; Sinha, B; Haslberger, C; Eigler, A; Endres, S

    1996-01-01

    Suppression of tumor necrosis factor-alpha (TNF) synthesis is one major target in pharmacological immunomodulation. We now showed the synergistic suppressive effect of the specific type IV phosphodiesterase inhibitor, rolipram, and of the stable prostacyclin analogue, cicaprost, on TNF synthesis. Th

  5. Isolation and Partial Characterization of a Cyclic GMP-Dependent Cyclic GMP-Specific Phosphodiesterase from Dictyostelium discoideum

    Bulgakov, Roman; Haastert, Peter J.M. van

    1983-01-01

    The cellular slime mold, Dictyostelium discoideum, contains at least two classes of phosphodiesterase activity. One class of enzymes hydrolyses cyclic AMP (cAMP) and cyclic GMP (cGMP) with approximately equal rates. Another enzyme, which is less than 5% of the total activity, specifically hydrolyses

  6. Dissociable effects of acetylcholinesterase inhibitors and phosphodiesterase type 5 inhibitors on object recognition memory: acquisition versus consolidation

    Prickaerts, L.; Sik, A.; Staay, van der F.J.; Vente, de J.; Blokland, A.

    2005-01-01

    Rationale Phosphodiesterase enzyme type 5 (PDE5) inhibitors and acetylcholinesterase (AChE) inhibitors have cognition-enhancing properties. However, it is not known whether these drug classes affect the same memory processes. Objective We investigated the memory-enhancing effects of the PDE5 inhibit

  7. Phosphodiesterases Inhibition by Bacilli Calmette-Guérin Contributes to Decrease Asthma in Allergic Rats

    Yajuan Wang

    2011-09-01

    Full Text Available Phosphodiesterases  (PDE  hydrolyse intracellular cAMP  and  cGMP  to  inactive  5’ monophosphates. Decreased level of cAMP is involved in the pathogenesis of asthma. We and others have shown that phosphodiesterases were upregulated in the lung of allergic rats, and Bacilli Calmette-Guérin (BCG induced the production of cAMP in vitro. However, it is unclear how BCG’s effect asthma and whether it is related to PDEs.In  this  study,  BCG  was  intraperitoneally  injected  into  male  Sprague-Dawley rats sensitized and later the rats were challenged with ovabumin/pertusis. The inflammation in lungs was measured. Airway hyperresponsiveness was determined using MedLab software after intravenous methacholine challenge. Furthermore,  cAMP level and adenylate cyclase activity in lungs were analyzed by ELISA, phosphodiesterases activities were analyzed by HPLC, while PDEs mRNA levels in lungs was analyzed by reverse transcription-polymerase chain  reaction.  Administration  of  BCG  significantly attenuated  allergen-induced  lung inflammatory response  and  hyper  responsiveness  as  compared  with  vehicle treatment. Furthermore,  the  levels of  cAMP in lungs were significantly increased in  BCG-treated allergic rats. Interestingly, administration of BCG decreased the activity of cAMP-PDE, but not adenylyl cyclase (AC, activity in lungs of animals. Furthermore, pretreatment with BCG significantly decreased the mRNA levels of PDE4A, 4C, 5 and 8, which were induced in lungs of allergic rats.BCG  administration  attenuated  airway inflammatory  response  and  bronchial  hyper responsiveness in rats, which are the most important symptoms in asthma. The decreased PDEs  mRNA  and  inhibited cAMP-PDE  activities by BCG  contribute,  at least in part, prevention of allergen-induced airway inflammation and asthma in rats.

  8. Effects of phosphodiesterase 4 inhibitor on cough response in guinea pigs sensitized and challenged with ovalbumin

    吕寒静; 邱忠民; 魏为利; 余莉; 刘瑞麟; 张敏

    2004-01-01

    Background There is currently considerable interest in the potential value of selective inhibitors of cyclic nucleotide phosphodiesterase 4 in the treatment of asthma. However, whether they influence eosinophilic airway inflammation-associated cough remains unclear. The objective of this study was to investigate the effects of selective phosphodiesterase 4 inhibitor SB207499 on cough response and airway inflammation in guinea pigs sensitized and challenged with ovalbumin. Methods Forty sensitized guinea pigs were randomly divided into four groups: control (n=10), challenge (n=10), SB207499 (n=10) and aminophylline (n=10), then challenged with aerosol of 1% ovalbumin or saline. Two hours later, animals were intraperitoneally injected with either saline, 25 mg/kg of SB207499 or aminophylline. At the 24th hour, the injection was repeated with 2.5 mg/kg and 25 mg/kg SB207499 or aminophylline, then cough response to inhaled capsaicin and airway responsiveness to methacholine inducing a 150% of the peak airway pressure to the baseline (PC150) was measured. Finally, total cell number and differentials in bronchoalveolar lavage fluid were analysed. Results The cough frequency per 3 minutes and PC150 in the challenge group were (22±4) times/3 minutes and (198±54) μg/ml, which were significantly different from (6±2) times/3 minutes and (691±81) μg/ml in the control group (P<0.05, respectively). The injection of 25 mg/kg SB207499 significantly inhibited the increased cough response and airway hyperresponsiveness, the cough frequency and PC150 in guinea pigs were (13±2) times/3 minutes and (680±81) μg/ml (P<0.05), which differed significantly from (18±2) times/3 minutes and (400±86) μg/ml after the administration of the same dose of aminophylline (P<0.05). The inhibition of SB207499 on cough response was dose-dependent. Similarly, SB207499 decreased the total cell number and percentage of eosinophils in bronchoalveolar lavage fluid to (2.1±0.5)×106/ml and (20±5

  9. Nitric oxide-induced changes in endothelial expression of phosphodiesterases 2, 3, and 5

    Schankin, Christoph J; Kruse, Lars S; Reinisch, Veronika M; Jungmann, Steffen; Kristensen, Julie C; Grau, Stefan; Ferrari, Uta; Sinicina, Inga; Goldbrunner, Roland; Straube, Andreas; Kruuse, Christina

    2010-01-01

    OBJECTIVE: To investigate nitric oxide (NO)-mediated changes in expression of cyclic nucleotide degrading phosphodiesterases 2A (PDE2A), PDE3B, and PDE5A in human endothelial cells. BACKGROUND: Nitric oxide induces production of cyclic guanosine monophosphate (cGMP), which along with cyclic...... adenosine monophosphate (cAMP) is degraded by PDEs. NO donors and selective inhibitors of PDE3 and PDE5 induce migraine-like headache and play a role in endothelial dysfunction during stroke. The current study investigates possible NO modulation of cGMP-related PDEs relevant to headache induction in a cell...... line containing such PDEs. METHODS: Real time polymerase chain reaction and Western blots were used to show expression of PDE2A, PDE3B, and PDE5A in a stable cell line of human brain microvascular endothelial cells. Effects of NO on PDE expression were analyzed at specific time intervals after...

  10. Determination of phosphodiesterase-5 inhibitors and analogs using high-performance liquid chromatography with ultraviolet detection.

    Nickum, Elisa A; Flurer, Cheryl L

    2015-01-01

    A considerable number of erectile dysfunction products, and dietary supplements suspected of containing phosphodiesterase-5 (PDE-5) inhibitors, have been analyzed by the US Food and Drug Administration. Often these samples are found to contain the approved active pharmaceutical ingredients (APIs) such as sildenafil, tadalafil or vardenafil. However, analogs of these APIs have also been identified in many samples and products containing multiple PDE-5 inhibitors have also been found. A single high-performance liquid chromatography with ultraviolet detection method has been developed for the determination of sildenafil, tadalafil, vardenafil and a number of commonly encountered analogs in pharmaceutical dosage forms and dietary supplement products, including tablets, capsules, bulk powders, troches and liquids. This method was designed as an alternative to methods developed for the determination of a single PDE-5 inhibitor. Using this protocol, 14 PDE-5 inhibitor compounds can be separated and determined in a single analysis. PMID:24668043

  11. Does phosphodiesterase inhibition lessen facial flap necrosis in tobacco cigarette users?

    Pfaff, Miles; Shah, Ajul; Steinbacher, Derek

    2014-02-01

    Tobacco cigarette smoking remains a serious risk factor for necrosis of local facial skin flaps. To date, no pharmacological therapies exist for cigarette smoke-induced impairment of skin flap tissue survival. Accumulating evidence suggest that phosphodiesterase-5 (PDE-5) inhibitor therapy may counteract the negative effects of cigarette smoke on flap survival. Here, we evaluate skin flap survival in a series of consecutive tobacco cigarette users treated with the PDE-5 inhibitor, sildenafil, who underwent local flap facial reconstruction. We included 11 patients (5 females; median age: 64) with a significant smoking history. Seventeen facial flaps were performed for 14 defects. All patients received sildenafil in the postoperative setting. One complication of necrosis of the flap distal margin was encountered. Follow-up was available for all patients. Our results demonstrate that facial reconstruction in tobacco cigarette smokers can be performed with improved success and that sildenafil therapy may mitigate the deleterious effects of smoking on flap survival. PMID:24488644

  12. PHOSPHODIESTERASE-5 INHIBITORS USE IN PATIENTS WITH ERECTILE DYSFUNCTION AND CARDIOVASCULAR DISEASE IN CLINICAL PRACTICE

    M. N. Mamedov

    2016-01-01

    Full Text Available About 150 million men worldwide and about 50% of men aged 40-88 y.o. in outpatient practice suffer from erectile dysfunction (ED. There is a linear relation between the age and ED rate. The main reason of ED in the majority of men (about 80% of patients is cardiovascular diseases (atherosclerosis, hypertension, diabetes mellitus, as well as certain risk factors (smoking, alcohol abuse, physical inactivity etc.. The problem of ED in cardiac outpatients and modern pharmacotherapy is discussed. The phosphodiesterase-5 (PDE5 inhibitors increase the relaxing effect of nitric oxide and increase cyclic GMP levels during sexual arousal. It results in increase of cavernosum blood flow, contributing to the physiological erection. Three PDE5 inhibitors (sildenafil, tadalafil, vardenafil are used in clinical practice nowadays.

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

    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...... that PDE3, PDE4, PDE7 and PDE8 are the major families present while PDE11A was not detected. PDE8B was differentially expressed during folliculogenesis. In cultured GCs, inhibition of PDE7 and PDE8 increased basal progesterone secretion while PDE4 inhibition increased forskolin-stimulated progesterone...

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

    Liebenberg, Nico

    2010-01-01

    Major depression is one of the most debilitating diseases of our time, while current antidepressant treatments remain deficient in several ways. The nitric oxide (NO) / cyclic guanosine monophosphate (cGMP) / cGMP-dependent protein kinase (PK-G) pathway shows promise as a novel target for the drug...... 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...... in Sprague Dawley rats. In the current study we explored the antidepressant-like properties of PDE5 inhibitors in Flinders Sensitive Line (FSL) rats, a genetic animal model of depression, and investigated the mechanism(s) that may be involved in the antidepressant-like activity of these drugs. We...

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

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

    2010-01-01

    BACKGROUND: Mice with targeted deletion of neuronal nitric oxide (NO) synthase (nNOS⁻(/)⁻) display inability to increase plasma renin concentration (PRC) in response to sodium restriction. nNOS has a distinct expression at the macula densa (MD), and in the present study, it was tested whether n......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...

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

    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.

  17. NAD[S], an NAD analogue with reduced susceptibility to phosphodiesterase. Chemical synthesis and enzymic properties.

    Meyer, T; Wielckens, K; Thiem, J; Hilz, H

    1984-05-01

    The chemical synthesis of adenosine(5') [alpha-thio]diphospho(5')ribofuranosyl-nicotinamide (NAD[S]) is described. The product occurs as a pair of diastereomers with different configuration at the sulfur-bearing phosphorus atom. The diastereomers were separated by high-performance liquid chromatography and their absolute configuration was determined after chemical degradation to the ADP[alpha S] diastereomers and chromatographic comparison with enzymically synthesized ADP[alpha S] diastereomers of known absolute configuration. Additional support for this assignment is based on different rates in the phosphodiesterase-catalyzed hydrolysis. Furthermore the synthesis of [14C]NAD[S] is described. The coenzyme activity of NAD[S] in the reaction with alcohol dehydrogenase from baker's yeast and lactate dehydrogenase from pig heart is very similar to that of beta-NAD. Also, NAD and NAD[S] serve equally well as substrates for NAD glycohydrolase from calf spleen. In contrast, no reaction was detected with NAD pyrophosphorylase, and hydrolysis of the separated NAD[S] diastereomers with snake venom phosphodiesterase showed a 26-fold and a 33-fold slower reaction rate than that of NAD. Nucleotide pyrophosphatase was less sensitive to the S substitution, hydrolyzing NAD[S] 14-times slower than NAD. Poly(ADP-ribose) polymerase from Ehrlich ascites tumor cell nuclei accepted NAD[S] as a substrate but the reaction was significantly slower and approached saturation at much lower values than with NAD. Alkaline hydrolysis of the products insoluble in trichloroacetic acid yielded AMP[S] as the main derivative. It is concluded that with NAD[S] as a substrate the nuclear acceptors were nearly exclusively mono(ADP-ribosyl) ated . PMID:6144544

  18. Radioisotopic determination of rat liver adenosine 3',5'-monophosphate phosphodiesterase by chromatography on aluminium oxide columns

    An AMP(c) separation technique was developed, its advantage over other techniques being that is does not involve a 5'-nucleotidase. In the event of a phosphodiesterase activation or inhibition it would otherwise be difficult to establish whether the modified enzyme activity is that of phosphodiesterase or that of 5'-nucleotidase. This method also gives good reproducibility in the separation yields and hence allows mass determinations. Many investigations having shown that 3'5'-adenosine monophosphate phosphohydrolase exists in at least two molecular forms it was decided to work at a high substrate concentration, 2.5 10-3M; the results show that the reaction is linear up to 30 minutes incubation, and furthermore proportional to the quantity of proteins up to at least 180μg. It is shown in addition that PDE which hydrolyses AMP(c) appears in two forms, one soluble and highly active, the other bound to hepatocyte plasmic membrane but less active

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

    Smith-Harrison, L.I.; Patel, Abhishek

    2016-01-01

    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.

  20. The Heme-Based Oxygen-Sensor Phosphodiesterase Ec DOS (DosP: Structure-Function Relationships

    Toru Shimizu

    2013-06-01

    Full Text Available Escherichia coli Direct Oxygen Sensor (Ec DOS, also known as Ec DosP is a heme-based O2-sensing phosphodiesterase from Escherichia coli that catalyzes the conversion of cyclic-di-GMP to linear di-GMP. Cyclic-di-GMP is an important second messenger in bacteria, highlighting the importance of understanding structure-function relationships of Ec DOS. Ec DOS is composed of an N-terminal heme-bound O2-sensing PAS domain and a C-terminal phosphodiesterase catalytic domain. Notably, its activity is markedly enhanced by O2 binding to the heme Fe(II complex in the PAS sensor domain. X-ray crystal structures and spectroscopic and catalytic characterization of the wild-type and mutant proteins have provided important structural and functional clues to understanding the molecular mechanism of intramolecular catalytic regulation by O2 binding. This review summarizes the intriguing findings that have obtained for Ec DOS.

  1. A role of phosphodiesterase-3B pathway in mediating leptin action on proopiomelanocortin and neurotensin neurons in the hypothalamus

    Sahu, Abhiram

    2010-01-01

    Leptin signaling in the hypothalamus is required for normal food intake and body weight homeostasis. Recent evidence suggests that besides the signal transducer and activator of transcription-3 (STAT3) pathway, several non-STAT3 pathways mediate leptin signaling in the hypothalamus. We have previously demonstrated that leptin stimulates phosphodiesterase-3B (PDE3B) activity in the hypothalamus, and PDE3 inhibitor cilostamide reverses anorectic and bodyweight reducing effects of leptin. To est...

  2. Selective inhibition of phosphodiesterase 1 relaxes urinary bladder smooth muscle: role for ryanodine receptor-mediated BK channel activation

    Xin, Wenkuan; Soder, Rupal P; Cheng, Qiuping; Eric S. Rovner; Petkov, Georgi V.

    2012-01-01

    The large conductance voltage- and Ca2+-activated K+ (BK) channel is a major regulator of detrusor smooth muscle (DSM) excitability and contractility. Recently, we showed that nonselective phosphodiesterase (PDE) inhibition reduces guinea pig DSM excitability and contractility by increasing BK channel activity. Here, we investigated how DSM excitability and contractility changes upon selective inhibition of PDE type 1 (PDE1) and the underlying cellular mechanism involving ryanodine receptors ...

  3. Synthesis of Quinoline Derivatives: Discovery of a Potent and Selective Phosphodiesterase 5 Inhibitor for the Treatment of Alzheimer's disease

    Fiorito, Jole; Saeed, Faisal; Zhang, Hong; Staniszewski, Agnieszka; Feng, Yan; Francis, Yitshak I.; Rao, Sudha; Thakkar, Devarshi M.; Deng, Shi-Xian; Landry, Donald W.; Arancio, Ottavio

    2012-01-01

    Phosphodiesterase type 5 (PDE5) mediates the degradation of cGMP in a variety of tissues including brain. Recent studies have demonstrated the importance of the nitric oxide/cGMP/cAMP-responsive element-binding protein (CREB) pathway to the process of learning and memory. Thus, PDE5 inhibitors (PDE5Is) are thought to be promising new therapeutic agents for the treatment of Alzheimer's disease (AD), a neurodegenerative disorder characterized by memory loss. To explore this possibility, a serie...

  4. Hyperoxia Increases Phosphodiesterase 5 (PDE5) Expression and Activity in Ovine Fetal Pulmonary Artery Smooth Muscle Cells

    Farrow, Kathryn N.; Groh, Beezly S.; Schumacker, Paul T.; Lakshminrusimha, Satyan; Czech, Lyubov; Gugino, Sylvia F.; Russell, James A.; Steinhorn, Robin H.

    2007-01-01

    In the pulmonary vasculature, cGMP concentrations are regulated in part by a cGMP-dependent phosphodiesterase, PDE5. Infants with persistent pulmonary hypertension of the newborn (PPHN) are often mechanically ventilated with high oxygen concentrations. The effects of hyperoxia on the developing pulmonary vasculature and PDE5 are largely unknown. Here, we demonstrate that exposure of fetal pulmonary artery smooth muscle cells (FPASMC) to high levels of oxygen for 24 hours leads to decreased re...

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

    Li, Longhu; Haider, Husnain Kh; WANG, Linlin; Lu, Gang; Ashraf, Muhammad

    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...

  6. Conformational Variations of Both Phosphodiesterase-5 and Inhibitors Provide the Structural Basis for the Physiological Effects of Vardenafil and Sildenafil

    Wang, Huanchen; Ye, Mengchun; Robinson, Howard; Francis, Sharron H.; Ke, Hengming

    2007-01-01

    Vardenafil has higher affinity to phosphodiesterase-5 (PDE5) than sildenafil and lower administered dosage for the treatment of erectile dysfunction. However, the molecular basis for these differences is puzzling because two drugs have similar chemical structures. Reported here is a crystal structure of the fully active and nonmutated PDE5A1 catalytic domain in complex with vardenafil. The structure shows that the conformation of the H-loop in the PDE5A1-vardenafil complex is different from t...

  7. The role of phosphodiesterase type-5 inhibitors in treatment of lower urinary tract symptoms associated with benign prostatic hyperplasia

    Umul, Mehmet; Serel, Tekin Ahmet

    2013-01-01

    Phosphodiesterase type-5 (PDE-5) inhibitors are approved as the first line of therapy for the treatment of erectile dysfunction. However, different studies have been performed to study the use of these agents in other areas of urology. There are many studies related to the use of PDE-5 inhibitors as a monotherapy or combination therapy with alpha-blockers for lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH). It has been shown that contractions induced by ...

  8. In Vivo Reconstitution of the Negative Feedback in Nitric Oxide/cGMP Signaling: Role of Phosphodiesterase Type 5 Phosphorylation

    Mullershausen, Florian; Russwurm, Michael; Koesling, Doris; Friebe, Andreas

    2004-01-01

    Most effects of the messenger molecule nitric oxide (NO) are mediated by cGMP, which is formed by NO-sensitive guanylyl cyclase (GC) and degraded by phosphodiesterases (PDEs). In platelets, NO elicits a spike-like cGMP response and causes a sustained desensitization. Both characteristics have been attributed to PDE5 activation caused by cGMP binding to its regulatory GAF domain. Activation is paralleled by phosphorylation whose precise function remains unknown. Here, we report reconstitution ...

  9. Endothelial Dysfunction, Erectile Dysfunction and Phosphodiesterase 5 Inhibitors. An Update of the Current Data and Future Perspectives

    Angelis Konstantinopoulos; Konstantinos Giannitsas; Spiros Raptis; Petros Perimenis

    2007-01-01

    Endothelial dysfunction is a pathological entity that multiply affects the health status. Erectile dysfunction is being recognized as a condition that is strongly interrelated with endothelial dysfunction, being a vascular event itself. Oral pharmacotherapy for erectile dysfunction has provided us with a new armamentarium on this condition. Phosphodiesterase 5 inhibitors have been investigated and proved useful in clinical practice for erectile dysfunction but in addition to this, the results...

  10. Dissociable effects of acetylcholinesterase inhibitors and phosphodiesterase type 5 inhibitors on object recognition memory: acquisition versus consolidation

    Prickaerts, L.; SIK, A.; Staay, van der, F.J.; Vente, de, W.; Blokland, A.

    2005-01-01

    Rationale Phosphodiesterase enzyme type 5 (PDE5) inhibitors and acetylcholinesterase (AChE) inhibitors have cognition-enhancing properties. However, it is not known whether these drug classes affect the same memory processes. Objective We investigated the memory-enhancing effects of the PDE5 inhibitor sildenafil and AChE inhibitors metrifonate and donepezil in the object recognition task to find out whether acquisition or consolidation processes were affected by these drugs. Methods The objec...

  11. Switching from Nitrate Therapy to Ranolazine in Patients with Coronary Artery Disease Receiving Phosphodiesterase Type-5 Inhibitors for Erectile Dysfunction

    Udeoji, Dioma U; Ernst R. Schwarz

    2014-01-01

    Coronary artery disease (CAD) and erectile dysfunction (ED) frequently coexist. The introduction of phosphodiesterase type-5 (PDE-5) inhibitors has revolutionized medical management of organic ED; however, in patients with angina pectoris, a common symptom of CAD, coadministration of PDE-5 inhibitors and nitrates has been implicated in CAD-related deaths following sexual activity. The mechanism of action of PDE-5 inhibitors results in a potential cumulative drop in blood pressure (BP); thus, ...

  12. Retinal degeneration is rescued in transgenic rd mice by expression of the cGMP phosphodiesterase beta subunit.

    Lem, J.; Flannery, J. G.; Li, T; Applebury, M L; Farber, D B; Simon, M. I.

    1992-01-01

    The beta subunit of the cGMP phosphodiesterase (PDE) gene has been identified as the candidate gene for retinal degeneration in the rd mouse. To study the molecular mechanisms underlying degeneration and the potential for gene repair, we have expressed a functional bovine cGMP PDE beta subunit in transgenic rd mice. One transgenic mouse line showed complete photoreceptor rescue across the entire span of the retina. A second independently derived line showed partial rescue in which photorecept...

  13. Retinal degeneration is rescued in transgenic rd mice by expression of the cGMP phosphodiesterase ß subunit

    Lem, Janis; Flannery, John G.; Li, Tiansen; Applebury, Meredithe L.; Farber, Debora B.; Simon, Melvin I.

    1992-01-01

    The ß subunit of the cGMP phosphodiesterase (PDE) gene has been identified as the candidate gene for retinal degeneration in the rd mouse. To study the molecular mechanisms underlying degeneration and the potential for gene repair, we have expressed a functional bovine cGMP PDE ß subunit in transgenic rd mice. One transgenic mouse line showed complete photoreceptor rescue across the entire span of the retina. A second independently derived line showed partial rescue in which photoreceptors in...

  14. Protein Kinase G-dependent Cardioprotective Mechanism of Phosphodiesterase-5 Inhibition Involves Phosphorylation of ERK and GSK3β*

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

    2008-01-01

    Sildenafil, a potent inhibitor of phosphodiesterase-5 (PDE-5) induces powerful protection against myocardial ischemia-reperfusion injury. PDE-5 inhibition increases cGMP levels that activate cGMP-dependent protein kinase (PKG). However, the cause and effect relationship of PKG in sildenafil-induced cardioprotection and the downstream targets of PKG remain unclear. Adult ventricular myocytes were treated with sildenafil and subjected to simulated ischemia and reoxygenat...

  15. A phosphodiesterase 4-controlled switch between memory extinction and strengthening in the hippocampus.

    Roesler, Rafael; Reolon, Gustavo K; Maurmann, Natasha; Schwartsmann, Gilberto; Schröder, Nadja; Amaral, Olavo B; Valvassori, Samira; Quevedo, João

    2014-01-01

    Established fear-related memories can undergo phenomena such as extinction or reconsolidation when recalled. Extinction probably involves the creation of a new, competing memory trace that decreases fear expression, whereas reconsolidation can mediate memory maintenance, updating, or strengthening. The factors determining whether retrieval will initiate extinction, reconsolidation, or neither of these two processes include training intensity, duration of the retrieval session, and age of the memory. However, previous studies have not shown that the same behavioral protocol can be used to induce either extinction or reconsolidation and strengthening, depending on the pharmacological intervention used. Here we show that, within an experiment that leads to extinction in control rats, memory can be strengthened if rolipram, a selective inhibitor of phosphodiesterase type 4 (PDE4), is administered into the dorsal hippocampus immediately after retrieval. The memory-enhancing effect of rolipram lasted for at least 1 week, was blocked by the protein synthesis inhibitor anisomycin, and did not occur when drug administration was not paired with retrieval. These findings indicate that the behavioral outcome of memory retrieval can be pharmacologically switched from extinction to strengthening. The cAMP/protein kinase A (PKA) signaling pathway might be a crucial mechanism determining the fate of memories after recall. PMID:24672454

  16. Isoquinoline-1,3-diones as Selective Inhibitors of Tyrosyl DNA Phosphodiesterase II (TDP2).

    Kankanala, Jayakanth; Marchand, Christophe; Abdelmalak, Monica; Aihara, Hideki; Pommier, Yves; Wang, Zhengqiang

    2016-03-24

    Tyrosyl DNA phosphodiesterase II (TDP2) is a recently discovered enzyme that specifically repairs DNA damages induced by topoisomerase II (Top2) poisons and causes resistance to these drugs. Inhibiting TDP2 is expected to enhance the efficacy of clinically important Top2-targeting anticancer drugs. However, TDP2 as a therapeutic target remains poorly understood. We report herein the discovery of isoquinoline-1,3-dione as a viable chemotype for selectively inhibiting TDP2. The initial hit compound 43 was identified by screening our in-house collection of synthetic compounds. Further structure-activity relationship (SAR) studies identified numerous analogues inhibiting TDP2 in low micromolar range without appreciable inhibition against the homologous TDP1 at the highest testing concentration (111 μM). The best compound 64 inhibited recombinant TDP2 with an IC50 of 1.9 μM. The discovery of this chemotype may provide a platform toward understanding TDP2 as a drug target. PMID:26910725

  17. Homocysteine and copper interact to promote type 5 phosphodiesterase expression in rabbit cavernosal smooth muscle cells

    Matthew Hotston; Jamie Y.Jeremy; Jonathon Bloor; Nick S.Greaves; Raj Persad; Giarmi Angelini; Nilima Shukla

    2008-01-01

    Aim: To study the effects of homocysteine and copper on type 5 phosphodiesterase (PDE5) expression in cavernosal vascular smooth muscle cells (CVSMCs) and to investigate superoxide (O2) derived from nicotinamide adenine dinucleotide phosphate oxidase as homocysteine and copper generate O2, and O2- upregulates PDE5 expression.Methods: CVSMCs derived from rabbit penis were incubated with homocysteine or copper chloride with or without superoxide dismutase (SOD), catalase, sildenafil citrate, or apocynin (nicotinamide adenine dinucleotide phosphate inhibitor) for 16 h. The expression of PDE5 and of glyceraldehyde-3-phosphate dehydrogenase (internal standard) was assessed using Western blot analysis. In parallel, O2 was measured spectrophotometrically. Results: CuCl2alone (up to 10 μmol/L) and homocysteine alone (up to 100 μmol/L) had no effect on O2 formation in CVSMCs compared to controls. In combination, however, homocysteine and CuCl2 arkedly increased O2 formation, an effect blocked by SOD, catalase, apocynin, and sildenafil (1 μmol/L) when co-incubated over the same time course.PDE5 expression was also significantly increased in CVSMCs incubated with homocysteine and CuCl2, compared to controls. This effect was also negated by 16-h co-incubation with SOD, catalase, apocynin and sildenafil. Conclusion:This represents a novel pathogenic mechanism underlying ED, and indicates that the therapeutic actions of prolonged sildenafil use are mediated in part through inhibition of this pathway.

  18. The role of phosphodiesterase-5 inhibitors in prostatic inflammation: a review.

    Peixoto, Christina Alves; Gomes, Fabiana Oliveira Dos Santos

    2015-01-01

    Clinical and basic experimental evidence indicates that chronic inflammation is the greatest factor in benign prostatic hyperplasia (BPH) progression, which is the most common cause of Lower Urinary Tract Symptoms (LUTS). The use of anti-inflammatory agents such as steroids, cyclooxygenase-2 (COX-2) and phytotherapics have been investigated as forms of treatment for various prostate diseases. Recent evidence has demonstrated that PDE5 inhibitors (PDE5Is) improve symptoms of BPH/LUTS, possibly as a result of the relaxing of the smooth muscle fibers of the bladder and prostate by NO/cGMPc signaling, or by improving RhoA/Rho-kinase (ROCK), and reduction of the hyperactivity of the autonomic nervous system. However, some results have suggested that besides vasodilatation and their anti-proliferative effect, PDE5Is exert a direct anti-inflammatory effect, by raising cGMP. Given that inflammation is major factor in benign prostatic hyperplasia (BPH) progression, PDE5Is could act also restore prostatic function as they act as potent anti-inflammatory drugs. This review aims to provide a comprehensive summary of the use of phosphodiesterase-5 inhibitors to treat prostatic inflammation. PMID:26379476

  19. Topical therapy for psoriasis: a promising future. Focus on JAK and phosphodiesterase-4 inhibitors.

    Rafael, Adilia; Torres, Tiago

    2016-01-01

    Psoriasis is a common, chronic and disabling skin disorder affecting approximately 2% of the population, associated with significant negative impact on the patient's quality of life. Approximately 80% of those affected with psoriasis have mild-to-moderate forms and are usually treated with topical therapy, whereas phototherapy and systemic therapies are used for those with severe disease. In the past three decades, the major advances in psoriasis therapy have been in systemic agents for the treatment of moderate-to-severe psoriasis, particularly new immunomodulatory and biological molecules, while topical therapies have remained relatively unchanged over the past decades. Indeed, topical corticosteroids and vitamin D3 analogs are still the gold standard of therapy for mild-to-moderate psoriasis. Thus, there is a need to develop new and more effective topical agents in the short and long term, with a better efficacy and safety profile than corticosteroids and vitamin D3 analogs. Over the past five years, investigation into topical therapy has expanded, with exciting new drugs being developed. Preliminary results of these emerging agents that selectively target disease-defining pathogenic pathways seem to be promising, although long-term and large-scale studies assessing safety and efficacy are still lacking. The aim of this article was to review the clinical and research data of some emerging topical agents, focusing on Janus kinase-signal transducer and activator of transcription and phosphodiesterase type 4 inhibitors, which are currently being investigated. PMID:26552963

  20. Discovery and modelling studies of natural ingredients from Gaultheria yunnanensis (FRANCH.) against phosphodiesterase-4.

    Cai, Ying-Hong; Guo, Yanqiong; Li, Zhe; Wu, Deyang; Li, Xiruo; Zhang, Heng; Yang, Junjie; Lu, Heng; Sun, Zhaowei; Luo, Hai-Bin; Yin, Sheng; Wu, Yinuo

    2016-05-23

    Phosphodiesterase-4 (PDE4) is an anti-inflammatory target for treatment of asthma and chronic obstructive pulmonary disease (COPD). Here, we report the isolation and characterization of 13 compounds (G1-G13) by bioassay-guided fractionation of the ethyl acetate extraction of Gaultheria yunnanensis (FRANCH.), one of which pentacyclic triterpene (G1) has never been reported. Four of them (G1, G2, G4, and G5) inhibit PDE4 with the IC50 values < 20 μM and G1 is the most potent ingredient with an IC50 of 245 nM and moderate selectivity over other PDE families. Molecular dynamics simulations suggest that G1 forms a hydrogen bond with Asn362, in addition to the hydrogen bond with Gln369 and π-π interactions with Phe372, which are commonly observed in the binding of most PDE4 inhibitors. The calculated binding free energies for the interactions of PDE4-G1 and PDE4-G2 are -19.4 and -18.8 kcal/mol, in consistence with the bioassay that G1 and G2 have IC50 of 245 nM and 542 nM, respectively. The modelling results of these active compounds may aid the rational design of novel PDE4 inhibitors as anti-inflammatory agents. PMID:26978121

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

    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.

  2. Phosphodiesterase 3 and 5 and cyclic nucleotide-gated ion channel expression in rat trigeminovascular system

    Kruse, Lars S; Sandholdt, Nicolai T H; Gammeltoft, Steen; Olesen, Jes; Kruuse, Christina Rostrup

    may be associated with mutations in ion channels. The aim of the present study was to describe the expression of phosphodiesterase 3 (PDE3) and 5 (PDE5) and cyclic nucleotide-gated ion channels (CNG) in cerebral arteries, meninges, and the trigeminal ganglion. mRNA for PDE and CNG was determined in...... the rat middle cerebral artery, basilar artery, trigeminal ganglion, and dura mater using real-time PCR. PDE and CNG proteins were identified using Western blot. For comparison, rat aorta and mesenteric artery were analysed. PDE3A, PDE3B, and PDE5A mRNA were detected in all tissues examined except for...... PDE3A mRNA in dura mater and the trigeminal ganglion. PDE5A and PDE3A protein expression was present in both cerebral andperipheral arteries, whereas PDE3B protein was present only in the cerebral arteries. The CNGA4 and B1 subunit mRNAs were detected in cerebral arteries and CNGA2 also in the...

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

    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.

  4. Phosphodiesterase 3 and 5 and cyclic nucleotide-gated ion channel expression in rat trigeminovascular system

    Kruse, Lars S; Sandholdt, Nicolai T H; Gammeltoft, Steen; Olesen, Jes; Kruuse, Christina Rostrup

    may be associated with mutations in ion channels. The aim of the present study was to describe the expression of phosphodiesterase 3 (PDE3) and 5 (PDE5) and cyclic nucleotide-gated ion channels (CNG) in cerebral arteries, meninges, and the trigeminal ganglion. mRNA for PDE and CNG was determined in...... the rat middle cerebral artery, basilar artery, trigeminal ganglion, and dura mater using real-time PCR. PDE and CNG proteins were identified using Western blot. For comparison, rat aorta and mesenteric artery were analysed. PDE3A, PDE3B, and PDE5A mRNA were detected in all tissues examined except for...... PDE3A mRNA in dura mater and the trigeminal ganglion. PDE5A and PDE3A protein expression was present in both cerebral and peripheral arteries, whereas PDE3B protein was present only in the cerebral arteries. The CNGA4 and B1 subunit mRNAs were detected in cerebral arteries and CNGA2 also in the...

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

    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.

  6. Phosphodiesterase-3 inhibitor (cilostazol) attenuates oxidative stress-induced mitochondrial dysfunction in the heart

    Siriporn C.Chattipakorn; Savitree Thummasorn; Jantira Sanit; Nipon Chattipakorn

    2014-01-01

    Background Cilostazol is a type 3 phosphodiesterase inhibitor which has been previously demonstrated to prevent the occurrence of tachyarrhythmia and improve defibrillation efficacy. However, the mechanism for this beneficial effect is still unclear. Since cardiac mito-chondria have been shown to play a crucial role in fatal cardiac arrhythmias and that oxidative stress is one of the main contributors to arr-hythmia generation, we tested the effects of cilostazol on cardiac mitochondria under severe oxidative stress. Methods Mitochondria were isolated from rat hearts and treated with H2O2 to induce oxidative stress. Cilostazol, at various concentrations, was used to study its protective effects. Pharmacological interventions, including a mitochondrial permeability transition pore (mPTP) blocker, cyclosporine A (CsA), and an inner membrane anion channel (IMAC) blocker, 4’-chlorodiazepam (CDP), were used to investigate the mechanistic role of cilostazol on cardiac mitochondria. Cardiac mitochondrial reactive oxygen species (ROS) production, mitochondrial membrane potential change and mi-tochondrial swelling were determined as indicators of cardiac mitochondrial function. Results Cilostazol preserved cardiac mitochondrial function when exposed to oxidative stress by preventing mitochondrial depolarization, mitochondrial swelling, and decreasing ROS produc-tion. Conclusions Our findings suggest that cardioprotective effects of cilostazol reported previously could be due to its prevention of car-diac mitochondrial dysfunction caused by severe oxidative stress.

  7. Targeting phosphodiesterase 3B enhances cisplatin sensitivity in human cancer cells

    We previously reported that human squamous cell carcinoma (SCC) cell lines refractory to cis-diaminedichloro-platinum II (cisplatin [CDDP]) had significant upregulation of the phosphodiesterase 3B gene (PDE3B), suggesting that inhibiting PDE3B suppresses CDDP resistance. shRNA-mediated PDE3B depletion in CDDP-resistant cells derived from SCC cells and Hela cells and induced CDDP sensitivity and inhibited tumor growth with elevated cyclic GMP induction resulting in upregulation of the multidrug-resistant molecule, but this did not occur in the 5-fluorouracil-resistant hepatocellular carcinoma cell lines. Furthermore, the antitumor growth effect of the combination of a PDE3B inhibitor (cilostazol) and CDDP in vivo was also greater than with either cilostazol or CDDP alone, with a significant increase in the number of apoptotic and cell growth-suppressive cancer cells in CDDP-resistance cell lines. Our results provided novel information on which to base further mechanistic studies of CDDP sensitization by inhibiting PDE3B in human cancer cells and for developing strategies to improve outcomes with concurrent chemotherapy

  8. Phosphodiesterase inhibition rescues chronic cognitive deficits induced by traumatic brain injury.

    Titus, David J; Sakurai, Atsushi; Kang, Yuan; Furones, Concepcion; Jergova, Stanislava; Santos, Rosmery; Sick, Thomas J; Atkins, Coleen M

    2013-03-20

    Traumatic brain injury (TBI) modulates several cell signaling pathways in the hippocampus critical for memory formation. Previous studies have found that the cAMP-protein kinase A signaling pathway is downregulated after TBI and that treatment with a phosphodiesterase (PDE) 4 inhibitor rolipram rescues the decrease in cAMP. In the present study, we examined the effect of rolipram on TBI-induced cognitive impairments. At 2 weeks after moderate fluid-percussion brain injury or sham surgery, adult male Sprague Dawley rats received vehicle or rolipram (0.03 mg/kg) 30 min before water maze acquisition or cue and contextual fear conditioning. TBI animals treated with rolipram showed a significant improvement in water maze acquisition and retention of both cue and contextual fear conditioning compared with vehicle-treated TBI animals. Cue and contextual fear conditioning significantly increased phosphorylated CREB levels in the hippocampus of sham animals, but not in TBI animals. This deficit in CREB activation during learning was rescued in TBI animals treated with rolipram. Hippocampal long-term potentiation was reduced in TBI animals, and this was also rescued with rolipram treatment. These results indicate that the PDE4 inhibitor rolipram rescues cognitive impairments after TBI, and this may be mediated through increased CREB activation during learning. PMID:23516287

  9. cGMP is tightly bound to bovine retinal rod phosphodiesterase

    Although the total concentration of cGMP in rod outer segments is thought to be substantially greater than the free concentration, no quantitatively relevant site for the bound cGMP has been described in mammalian photoreceptors. They have found that preparations of purified bovine rod photoreceptor cyclic nucleotide phosphodiesterase (PDE) contain 1.8 ± 0.3 mol of tightly bound cGMP per mol of PDE. When subunits of the purified PDE were separated by reverse-phase HPLC, a peak of material having spectral properties characteristic of a guanine ring was seen. This material was identified as cGMP. When incubated with 1μM [3H]cGMP, only 0.1 mol of [3H]cGMP bound per mol of purified PDE. Scatchard plots of [3H]cGMP binding have indicated that two classes of binding sites are present on the rod PDE. The observation that stoichiometric amounts of cGMP are tightly bound to PDE accounts for the inability to purify the bovine rod PDE on cGMP affinity columns or to demonstrate stoichiometric high-affinity binding sites with [3H]cGMP. More significantly, the tightly bound cGMP may resolve the apparent discrepancy between the free and total cGMP concentrations of photoreceptor outer segments

  10. Stimulation of Neural Stem Cell Proliferation by Inhibition of Phosphodiesterase 5

    Ana I. Santos

    2014-01-01

    Full Text Available The involvement of nitric oxide (NO and cyclic GMP (cGMP in neurogenesis has been progressively unmasked over the last decade. Phosphodiesterase 5 (PDE5 specifically degrades cGMP and is highly abundant in the mammalian brain. Inhibition of cGMP hydrolysis by blocking PDE5 is a possible strategy to enhance the first step of neurogenesis, proliferation of neural stem cells (NSC. In this work, we have studied the effect on cell proliferation of 3 inhibitors with different selectivity and potency for PDE5, T0156, sildenafil, and zaprinast, using subventricular zone-(SVZ- derived NSC cultures. We observed that a short- (6 h or a long-term (24 h treatment with PDE5 inhibitors increased SVZ-derived NSC proliferation. Cell proliferation induced by PDE5 inhibitors was dependent on the activation of the mitogen-activated protein kinase (MAPK and was abolished by inhibitors of MAPK signaling, soluble guanylyl cyclase, and protein kinase G. Moreover, sildenafil neither activated ERK1/2 nor altered p27Kip1 levels, suggesting the involvement of pathways different from those activated by T0156 or zaprinast. In agreement with the present results, PDE5 inhibitors may be an interesting therapeutic approach for enhancing the proliferation stage of adult neurogenesis.

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

    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.

  12. Phosphodiesterase 5 inhibitors lower both portal and pulmonary pressure in portopulmonary hypertension: a case report

    Bremer Hinrich C

    2007-07-01

    Full Text Available Abstract Background Portopulmonary hypertension (PPHTN is a severe complication in liver cirrhosis. PDE5 inhibitors lower pulmonary arterial pressure (PAP in PPHTN. However, their effect on portal hypertension has not yet been investigated. Case presentation A 55 year old male patient presented with PPHTN and alcoholic liver cirrhosis. 10 mg of Tadalafil, a PDE5 inhibitor with a long half-life, was administered orally under continuous monitoring of pulmonary and portal hemodynamics. For maintenance therapy the patient received Sildenafil 20 mg bid. Tadalafil lowered mean PAP from 45 to 39 mmHg within 60 minutes. Cardiac output (CO increased from 6.8 to 7.9 l/min. Central venous pressure (CVP remained stable at 3 mmHg. Systolic and diastolic blood pressure was lowered from 167/89 to 159/86 mmHg. Pulse rate increased from 75 to 87 per min. Wedged hepatic vein pressure (WHVP decreased from 21 to 18 mm Hg, hepatovenous pressure gradient (HVPG decreased from 10 to 7 mmHg. Hemodynamic monitoring after 6 months of Sildenafil therapy revealed a sustained lowering of mean PAP. HVPG remained constant at 10 mmHg. Cardiac and pulmonary performance had further improved. Conclusion This case report shows for the first time, that phosphodiesterase 5 inhibitors lower both portal and pulmonary pressure in portopulmonary hypertension.

  13. Inhibition of phosphodiesterase-4 promotes oligodendrocyte precursor cell differentiation and enhances CNS remyelination.

    Syed, Yasir A; Baer, Alexandra; Hofer, Matthias P; González, Ginez A; Rundle, Jon; Myrta, Szymon; Huang, Jeffrey K; Zhao, Chao; Rossner, Moritz J; Trotter, Matthew W B; Lubec, Gert; Franklin, Robin J M; Kotter, Mark R

    2013-12-01

    The increasing effectiveness of new disease-modifying drugs that suppress disease activity in multiple sclerosis has opened up opportunities for regenerative medicines that enhance remyelination and potentially slow disease progression. Although several new targets for therapeutic enhancement of remyelination have emerged, few lend themselves readily to conventional drug development. Here, we used transcription profiling to identify mitogen-activated protein kinase (Mapk) signalling as an important regulator involved in the differentiation of oligodendrocyte progenitor cells (OPCs) into oligodendrocytes. We show in tissue culture that activation of Mapk signalling by elevation of intracellular levels of cyclic adenosine monophosphate (cAMP) using administration of either dibutyryl-cAMP or inhibitors of the cAMP-hydrolysing enzyme phosphodiesterase-4 (Pde4) enhances OPC differentiation. Finally, we demonstrate that systemic delivery of a Pde4 inhibitor leads to enhanced differentiation of OPCs within focal areas of toxin-induced demyelination and a consequent acceleration of remyelination. These data reveal a novel approach to therapeutic enhancement of remyelination amenable to pharmacological intervention and hence with significant potential for translation. PMID:24293318

  14. Phosphodiesterase 5/protein kinase G signal governs stemness of prostate cancer stem cells through Hippo pathway.

    Liu, Naihua; Mei, Liu; Fan, Xueying; Tang, Chao; Ji, Xing; Hu, Xinhua; Shi, Wei; Qian, Yu; Hussain, Musaddique; Wu, Junsong; Wang, Chaojun; Lin, Shaoqiang; Wu, Ximei

    2016-08-01

    Cancer stem cells (CSC) are critical for initiation, metastasis, and relapse of cancers, however, the underlying mechanism governing stemness of CSC remains unknown. Herein, we have investigated the roles of phosphodiesterase 5 (PDE5) in stemness of prostate cancer cells. Both PDE5 and WW domain-containing transcription regulator protein-1 (TAZ), a core effector of Hippo pathway, are highly expressed in the PC3-derived cancer stem cells (PCSC). Either TAZ knockdown or inhibition of PDE5 activity attenuated colony formation, altered expression patterns of stem cell markers, and enhanced cisplatin cytotoxicity, resulting in attenuation of stemness in PCSC. In addition, inhibition of PDE5 activity by its specific inhibitors activates cGMP-dependent protein kinase G (PKG), which in turn induces MST/LATS kinases, resulting in cytosolic degradation of TAZ and activation of Hippo pathway. Accordingly, knockdown of TAZ almost completely abolished PDE5 inhibitor-induced attenuation in stemness in cultured PCSC, whereas knockdown of TAZ not only abolished PDE5 inhibitor-induced attenuation in stemness but also facilitated PDE5 inhibitor-induced trans-differentiation in PCSC xenografts. Together, the present study has uncovered that PDE/cGMP/PKG signal targets to Hippo/TAZ pathway in maintaining stemness of PCSC, and suggested that PDE5 inhibitors in combination with chemotherapeutic agents could effectively prevent initiation, metastasis, and relapse of prostate cancer. PMID:27179930

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

    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.

  16. Phosphodiesterase-5 inhibition mimics intermittent reoxygenation and improves cardioprotection in the hypoxic myocardium.

    Giuseppina Milano

    Full Text Available UNLABELLED: Although chronic hypoxia is a claimed myocardial risk factor reducing tolerance to ischemia/reperfusion (I/R, intermittent reoxygenation has beneficial effects and enhances heart tolerance to I/R. AIM OF THE STUDY: To test the hypothesis that, by mimicking intermittent reoxygenation, selective inhibition of phosphodiesterase-5 activity improves ischemia tolerance during hypoxia. Adult male Sprague-Dawley rats were exposed to hypoxia for 15 days (10% O₂ and treated with placebo, sildenafil (1.4 mg/kg/day, i. p., intermittent reoxygenation (1 h/day exposure to room air or both. Controls were normoxic hearts. To assess tolerance to I/R all hearts were subjected to 30-min regional ischemia by left anterior descending coronary artery ligation followed by 3 h-reperfusion. Whereas hypoxia depressed tolerance to I/R, both sildenafil and intermittent reoxygenation reduced the infarct size without exhibiting cumulative effects. The changes in myocardial cGMP, apoptosis (DNA fragmentation, caspase-3 activity (alternative marker for cardiomyocyte apoptosis, eNOS phosphorylation and Akt activity paralleled the changes in cardioprotection. However, the level of plasma nitrates and nitrites was higher in the sildenafil+intermittent reoxygenation than sildenafil and intermittent reoxygenation groups, whereas total eNOS and Akt proteins were unchanged throughout. CONCLUSIONS: Sildenafil administration has the potential to mimic the cardioprotective effects led by intermittent reoxygenation, thereby opening the possibility to treat patients unable to be reoxygenated through a pharmacological modulation of NO-dependent mechanisms.

  17. Structural Basis for Nucleotide Hydrolysis by the Acid Sphingomyelinase-like Phosphodiesterase SMPDL3A.

    Gorelik, Alexei; Illes, Katalin; Superti-Furga, Giulio; Nagar, Bhushan

    2016-03-18

    Sphingomyelin phosphodiesterase, acid-like 3A (SMPDL3A) is a member of a small family of proteins founded by the well characterized lysosomal enzyme, acid sphingomyelinase (ASMase). ASMase converts sphingomyelin into the signaling lipid, ceramide. It was recently discovered that, in contrast to ASMase, SMPDL3A is inactive against sphingomyelin and, surprisingly, can instead hydrolyze nucleoside diphosphates and triphosphates, which may play a role in purinergic signaling. As none of the ASMase-like proteins has been structurally characterized to date, the molecular basis for their substrate preferences is unknown. Here we report crystal structures of murine SMPDL3A, which represent the first structures of an ASMase-like protein. The catalytic domain consists of a central mixed β-sandwich surrounded by α-helices. Additionally, SMPDL3A possesses a unique C-terminal domain formed from a cluster of four α-helices that appears to distinguish this protein family from other phosphoesterases. We show that SMDPL3A is a di-zinc-dependent enzyme with an active site configuration that suggests a mechanism of phosphodiester hydrolysis by a metal-activated water molecule and protonation of the leaving group by a histidine residue. Co-crystal structures of SMPDL3A with AMP and α,β-methylene ADP (AMPCP) reveal that the substrate binding site accommodates nucleotides by establishing interactions with their base, sugar, and phosphate moieties, with the latter the major contributor to binding affinity. Our study provides the structural basis for SMPDL3A substrate specificity and sheds new light on the function of ASMase-like proteins. PMID:26792860

  18. Modulation of Polycystic Kidney Disease Severity by Phosphodiesterase 1 and 3 Subfamilies.

    Ye, Hong; Wang, Xiaofang; Sussman, Caroline R; Hopp, Katharina; Irazabal, Maria V; Bakeberg, Jason L; LaRiviere, Wells B; Manganiello, Vincent C; Vorhees, Charles V; Zhao, Haiqing; Harris, Peter C; van Deursen, Jan; Ward, Christopher J; Torres, Vicente E

    2016-05-01

    Aberrant intracellular calcium levels and increased cAMP signaling contribute to the development of polycystic kidney disease (PKD). cAMP can be hydrolyzed by various phosphodiesterases (PDEs). To examine the role of cAMP hydrolysis and the most relevant PDEs in the pathogenesis of PKD, we examined cyst development in Pde1- or Pde3-knockout mice on the Pkd2(-/WS25) background (WS25 is an unstable Pkd2 allele). These PDEs were selected because of their importance in cross-talk between calcium and cyclic nucleotide signaling (PDE1), control of cell proliferation and cystic fibrosis transmembrane conductance regulator (CFTR) -driven fluid secretion (PDE3), and response to vasopressin V2 receptor activation (both). In Pkd2(-/WS25) mice, knockout of Pde1a, Pde1c, or Pde3a but not of Pde1b or Pde3b aggravated the development of PKD and was associated with higher levels of protein kinase A-phosphorylated (Ser133) cAMP-responsive binding protein (P-CREB), activating transcription factor-1, and CREB-induced CRE modulator proteins in kidney nuclear preparations. Immunostaining also revealed higher expression of P-CREB in Pkd2(-/) (WS25);Pde1a(-/-), Pkd2(-) (/WS25);Pde1c(-/-), and Pkd2(-/) (WS25);Pde3a(-/-) kidneys. The cystogenic effect of desmopressin administration was markedly enhanced in Pkd2(-/WS25);Pde3a(-/-) mice, despite PDE3 accounting for only a small fraction of renal cAMP PDE activity. These observations show that calcium- and calmodulin-dependent PDEs (PDE1A and PDE1C) and PDE3A modulate the development of PKD, possibly through the regulation of compartmentalized cAMP pools that control cell proliferation and CFTR-driven fluid secretion. Treatments capable of increasing the expression or activity of these PDEs may, therefore, retard the development of PKD. PMID:26374610

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

    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.

  20. Phosphodiesterase 8a Supports HIV-1 Replication in Macrophages at the Level of Reverse Transcription

    Booiman, Thijs; Cobos Jiménez, Viviana; van Dort, Karel A.; van 't Wout, Angélique B.; Kootstra, Neeltje A.

    2014-01-01

    Background HIV-1 infected macrophages play a key role in HIV-1 infection. Even during anti-retroviral treatment, macrophages keep producing virus due to suboptimal tissue penetration and reduced efficacy of antiretrovirals. It is therefore of major importance to understand which host factors are involved in HIV-1 replication in macrophages. Previously, we have shown that genetic polymorphisms in phosphodiesterase 8a (PDE8A) are strongly associated with HIV-1 replication in these cells. Here we analyzed the mechanism and regulation of PDE8A in HIV-1 replication in macrophages. Results PDE8A mRNA expression strongly increases upon differentiation of monocytes into macrophages, which corresponds to the increased susceptibility of mature macrophages to HIV-1. In parallel, expression of microRNA miR-145-5p, predicted to target PDE8A mRNA, strongly decreased. The interaction of miR-145-5p with the 3′ UTR of PDE8A mRNA could be experimentally validated, suggesting that indeed miR-145-5p can regulate PDE8A expression levels. Knockdown of PDE8A in macrophages resulted in a decrease in total HIV-1 replication and proviral DNA levels. These observations confirm that PDE8A regulates HIV-1 replication in macrophages and that this effect is mediated through early steps in the viral replication cycle. Conclusions PDE8A is highly expressed in macrophages, and its expression is regulated by miR-145-5p. Our findings strongly suggest that PDE8A supports HIV-1 replication in macrophages and that this effect is mediated at the level of reverse transcription. PMID:25295610

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

    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.

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

    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. Direct photolabeling of the cGMP-stimulated cyclic nucleotide phosphodiesterase

    cGMP-stimulated phosphodiesterase (PDE) has been directly photolabeled with [32P]cGMP using UV light. Sequence analysis of peptide fragments obtained from partial proteolysis or cyanogen bromide cleavage indicate that two different domains are labeled. One site, on a Mr = 36,000 chymotryptic fragment located near the COOH terminus, has characteristics consistent with it being close to or part of the catalytic site of the enzyme. This peptide contains a region of sequence that is highly conserved in all mammalian cyclic nucleotide PDEs and has been postulated to contain the catalytic domain of the enzyme. The other site, on a Mr = 28,000 cyanogen bromide cleavage fragment located near the middle of the molecule, probably makes up part of the allosteric site of the molecule. Labeling of the enzyme is concentration dependent and Scatchard analysis of labeling yields a biphasic plot with apparent half labeling concentrations of about 1 and 30 microM consistent with two types of sites being labeled. Limited proteolysis of the PDE by chymotrypsin yields five prominent fragments that separate by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) at Mr = 60,000, 57,000, 36,000, 21,000, and 17,000. Both the Mr = 60,000 and 57,000 apparently have blocked NH2 termini suggesting that the Mr = 57,000 fragment is a subfragment of the Mr = 60,000 fragment. Primary sequence analysis indicates that both the Mr = 21,000 and 17,000 fragments are subfragments of the Mr = 36,000 fragment. Autoradiographs of photolabeled then partially proteolyzed enzyme show labeled bands at Mr = 60,000, 57,000, and 36,000. Addition of 5 microM cAMP prior to photolabeling eliminates photolabeling of the Mr = 36,000 fragment but not the Mr = 60,000 or 57,000 fragments

  4. Vascular dysfunction induced by hypochlorite is improved by the selective phosphodiesterase-5-inhibitor vardenafil.

    Radovits, Tamás; Arif, Rawa; Bömicke, Timo; Korkmaz, Sevil; Barnucz, Enikő; Karck, Matthias; Merkely, Béla; Szabó, Gábor

    2013-06-15

    Reactive oxygen species, such as hypochlorite induce oxidative stress, which impairs nitric oxide (NO)-cyclic guanosine monophosphate (cGMP) signalling and leads to vascular dysfunction. It has been proposed, that elevated cGMP-levels may contribute to an effective cytoprotection against oxidative stress. We investigated the effects of vardenafil, a selective inhibitor of the cGMP-degrading phosphodiesterase-5 enzyme on vascular dysfunction induced by hypochlorite. In organ bath experiments for isometric tension, we investigated the endothelium-dependent and endothelium-independent vasorelaxation of isolated rat aortic rings using cumulative concentrations of acetylcholine and sodium nitroprusside (SNP). Vascular dysfunction was induced by exposing rings to hypochlorite (100-400 µM). In the treatment groups, rats were pretreated with vardenafil (30 and 300 µg/kg i.v.). Immunohistochemical analysis was performed for the oxidative stress markers nitrotyrosine, poly(ADP-ribose) and for apoptosis inducing factor (AIF). Exposure to hypochlorite resulted in a marked impairment of acetylcholine-induced endothelium-dependent vasorelaxation of aortic rings. Pretreatment with vardenafil led to improved endothelial function as reflected by the higher maximal vasorelaxation (Rmax) to acetylcholine. Regarding endothelium-independent vasorelaxation, hypochlorite exposure led to a left-shift of SNP concentration-response curves in the vardenafil groups without any alterations of the Rmax. In the hypochlorite groups immunohistochemical analysis showed enhanced poly(ADP-ribose)-formation and nuclear translocation of AIF, which were prevented by vardenafil-pretreatment. Our results support the view that cytoprotective effects of PDE-5-inhibitors on the endothelium may underlie the improved endothelial function, however, a slight sensitisation of vascular smooth muscle to NO was also confirmed. PDE-5-inhibition may represent a potential therapy approach for treating vascular

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

    YuriA.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.

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

    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 C13, E12 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 [3H]cAMP) was rather sensitive to inhibition by p-chloromercuribenzoate (IC50, 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 (IC50, ∼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

  7. Characterization of the binding properties of T-773 as a PET radioligand for phosphodiesterase 10A

    Introduction: Phosphodiesterase 10A (PDE10A) is a dual-substrate PDE that hydrolyzes both cAMP and cGMP and is selectively expressed in striatal medium spiny neurons. Recent studies have suggested that PDE10A inhibition is a novel approach for the treatment of disorders such as schizophrenia and Huntington's disease. A positron emission tomography (PET) occupancy study can provide useful information for the development of PDE10A inhibitors. We discovered T-773 as a candidate PET radioligand for PDE10A and investigated its properties by in vitro autoradiography and a PET study in a monkey. Methods: Profiling of T-773 as a PET radioligand for PDE10A was conducted by in vitro enzyme inhibitory assay, in vitro autoradiography, and PET study in a monkey. Results: T-773 showed a high binding affinity and selectivity for human recombinant PDE10A2 in vitro; the IC50 value in an enzyme inhibitory assay was 0.77 nmol/L, and selectivity over other PDEs was more than 2500-fold. In autoradiography studies using mouse, rat, monkey, or human brain sections, radiolabeled T-773 selectively accumulated in the striatum. This selective accumulation was not observed in the brain sections of Pde10a-KO mice. The binding of [3H]T-773 to PDE10A in rat brain sections was competitively inhibited by MP-10, a selective PDE10A inhibitor. In rat brain sections, [3H]T-773 bound to a single high affinity site of PDE10A with Kd values of 12.2 ± 2.2 and 4.7 ± 1.2 nmol/L in the caudate-putamen and nucleus accumbens, respectively. In a monkey PET study, [11C]T-773 showed good brain penetration and striatum-selective accumulation. Conclusion: These results suggest that [11C]T-773 is a potential PET radioligand for PDE10A

  8. Pivotal effects of phosphodiesterase inhibitors on myocyte contractility and viability in normal and ischemic hearts

    Yuan James RAO; Lei XI

    2009-01-01

    Phosphodiesterases (PDEs) are enzymes that degrade cellular cAMP and cGMP and are thus essential for regulating the cyclic nucleotides. At least 11 families of PDEs have been identified, each with a distinctive structure, activity, expression, and tissue distribution. The PDE type-3, -4, and -5 (PDE3, PDE4, PDE5) are localized to specific regions of the cardiomyo-cyte, such as the sarcoplasmic reticulum and Z-disc, where they are likely to influence cAMP/cGMP signaling to the end effectors of contractility. Several PDE inhibitors exhibit remarkable hemodynamic and inotropic properties that may be valuable to clinical practice. In particular, PDE3 inhibitors have potent cardiotonic effects that can be used for short-term inotropic support, especially in situations where adrenergic stimulation is insufficient. Most relevant to this review, PDE in-hibitors have also been found to have cytoprotective effects in the heart. For example, PDE3 inhibitors have been shown to be cardioprotective when given before ischemic attack, whereas PDE5 inhibitors, which include three widely used erectile dysfunction drugs (sildenafil, vardenafil and tadalafil), can induce remarkable cardioprotection when administered either prior to ischemia or upon reperfusion. This article provides an overview of the current laboratory and clinical evidence, as well as the cellular mechanisms by which the inhibitors of PDE3, PDE4 and PDE5 exert their beneficial effects on normal and ischemic hearts. It seems that PDE inhibitors hold great promise as clinically applicable agents that can improve car-diac performance and cell survival under critical situations, such as ischemic heart attack, cardiopulmonary bypass surgery, and heart failure.

  9. Usage and perceptions of phosphodiesterase type 5 inhibitors among the male partners of infertile couples

    Kim, Dong Suk; Shim, Sung Han; Lim, Jung Jin; Yang, Seung Choul

    2016-01-01

    Objective We aimed to investigate the prevalence of erectile dysfunction (ED) and the usage of phosphodiesterase type 5 (PDE5) inhibitors for ED treatment in infertile couples. Methods A total of 260 male partners in couples reporting infertility lasting at least 1 year were included in this study. In addition to an evaluation of infertility, all participants completed the International Index of Erectile Function (IIEF)-5 questionnaire to evaluate their sexual function. The participants were asked about their use of PDE5 inhibitors while trying to conceive during their partner's ovulatory period and about their concerns regarding the risks of PDE5 inhibitor use to any eventual pregnancy and/or the fetus. Results Based on the IIEF-5 questionnaire, 41.5% of the participants (108/260) were classified as having mild ED (an IIEF-5 score of 17–21), while 10.4% of the participants (27/260) had greater than mild ED (an IIEF-5 score of 16 or less). The majority (74.2%, 193/260) of male partners of infertile couples had a negative perception of the safety of using a PDE5 inhibitor while trying to conceive. Only 11.1% of men (15/135) with ED in infertile couples had used a PDE5 inhibitor when attempting conception. Conclusion ED was found to be common in the male partners of infertile couples, but the use of PDE5 inhibitors among these men was found to be very low. The majority of male partners were concerned about the risks of using PDE5 inhibitors when attempting to conceive. Appropriate counseling about this topic and treatment when necessary would likely be beneficial to infertile couples in which the male partner has ED. PMID:27104154

  10. Application of neurophysiological biomarkers for Huntington's disease: evaluating a phosphodiesterase 9A inhibitor.

    Nagy, Dávid; Tingley, Francis D; Stoiljkovic, Milan; Hajós, Mihály

    2015-01-01

    Several neurophysiological abnormalities have been described in Huntington's disease, including auditory gating deficit, which are considered to reflect impaired brain information-processing. Since transgenic animal models of Huntington's disease capture basic neuropathology of the disorder, auditory gating was studied in BACHD (line5) transgenic rats and Q175 transgenic mice, together with local field gamma power in the hippocampus and primary auditory cortex. Using clinically equivalent acoustic-stimulation paradigms, impaired auditory gating was detected in transgenic BACHD rats under anesthesia and in freely-moving condition. In addition, transgenic BACHD rats showed a lower level of hippocampal and cortical field gamma band power compared to wild-type counterpart, which might be related to their compromised mitochondrial function. Systemic administration of the recently developed phosphodiesterase 9A (PDE9A) inhibitor PF-04447943 dose-dependently improved gating deficit in transgenic BACHD rats in both brain regions. Q175 mice, including wild-type, heterozygote and homozygote mice showed similarly poor gating, and administration of PF-04447943 was without effect. Treatment of transgenic BACHD rats with daily administration of PF-04447943 (1mg/kg) over 7-days resulted in an improvement in their auditory gating both in the hippocampus and primary auditory cortex as evaluated 24h after the last treatment. In fact, differences in auditory gating between wild-type and transgenic BACHD rats were totally abolished after sub-chronic treatment with the PDE9A inhibitor. Our findings indicate that BACHD transgenic rats show abnormal auditory gating with features resembling those of Huntington's disease patients, which could be considered as potential translational biomarker for drug development in treatment of this disease. PMID:25315303

  11. Effectiveness and safety of phosphodiesterase 5 inhibitors in patients with cardiovascular disease and hypertension.

    Chrysant, Steven G

    2013-10-01

    Phosphodiesterase 5 (PDE 5) inhibitors are selective inhibitors of the enzyme PDE 5, which catalyzes the hydrolysis of cyclic guanosine monophosphate (cGMP), a potent vasodilator and nitric oxide (NO) donor, to its corresponding metabolites (monophosphates). The enzyme PDE 5 is widely distributed in the body, including the heart and blood vessels. Because of its distribution, it was hypothesized that its inhibition could lead to significant coronary vasodilation, which would benefit patients with coronary artery disease (CAD). This hypothesis led to the development of PDE 5 inhibitors with the first being sildenafil citrate. Subsequent studies with sildenafil in patients with CAD demonstrated a modest cardiovascular effect, but a potent action on penile erection in men, resulting in sildenafil becoming a first-line therapy of erectile dysfunction (ED). Subsequently, two more PDE 5 inhibitors (vardenafil and tadalafil) were developed and approved by the Food and Drug Administration (FDA) for the treatment of ED. Recent studies have shown several pleiotropic beneficial effects of PDE 5 inhibitors in patients with CAD, hypertension, heart failure, pulmonary arterial hypertension, diabetes mellitus and Raynaud's phenomenon. Side effects and interactions of PDE 5 inhibitors with other drugs have been minimal, with the exception of their coadministration with nitrates, which could lead to severe vasodilation and hypotension and therefore, their coadministration is prohibited. All these pleiotropic cardiovascular effects of PDE 5 inhibitors and their drug interactions will be discussed in this concise review in the context of the American College of Cardiology / American Heart Association guidelines and the recent developments in this field. PMID:23917809

  12. Adjunctive Phosphodiesterase-4 Inhibitor Therapy Improves Antibiotic Response to Pulmonary Tuberculosis in a Rabbit Model

    Subbian, Selvakumar; Tsenova, Liana; Holloway, Jennifer; Peixoto, Blas; O'Brien, Paul; Dartois, Véronique; Khetani, Vikram; Zeldis, Jerome B.; Kaplan, Gilla

    2016-01-01

    Objectives Adjunctive host-directed therapy is emerging as a new potential approach to improve the outcome of conventional antimicrobial treatment for tuberculosis (TB). We tested the ability of a phosphodiesterase-4 inhibitor (PDE4i) CC-11050, co-administered with the first-line anti-TB drug isoniazid (INH), to accelerate bacillary killing and reduce chronic inflammation in the lungs of rabbits with experimental Mycobacterium tuberculosis (Mtb) infection. Methods A rabbit model of pulmonary TB that recapitulates the pathologic manifestations seen in humans was used. Rabbits were infected with virulent Mtb by aerosol exposure and treated for eight weeks with INH with or without CC-11050, starting at four weeks post infection. The effect of CC-11050 treatment on disease severity, pathology, bacillary load, T cell proliferation and global lung transcriptome profiles were analyzed. Results Significant improvement in bacillary clearance and reduced lung pathology and fibrosis were noted in the rabbits treated for eight weeks with INH + CC-11050, compared to those treated with INH or CC-11050 only. In addition, expression of host genes associated with tissue remodeling, tumor necrosis factor alpha (TNF-α) regulation, macrophage activation and lung inflammation networks was dampened in CC-11050-treated, compared to the untreated rabbits. Conclusions Adjunctive CC-11050 therapy significantly improves the response of rabbits with experimental pulmonary TB to INH treatment. We propose that CC-11050 may be a promising candidate for host directed therapy of patients with pulmonary TB, reducing the duration and improving clinical outcome of antibiotic treatment. PMID:26981575

  13. Loss of extra-striatal phosphodiesterase 10A expression in early premanifest Huntington's disease gene carriers.

    Wilson, Heather; Niccolini, Flavia; Haider, Salman; Marques, Tiago Reis; Pagano, Gennaro; Coello, Christopher; Natesan, Sridhar; Kapur, Shitij; Rabiner, Eugenii A; Gunn, Roger N; Tabrizi, Sarah J; Politis, Marios

    2016-09-15

    Huntington's disease (HD) is a monogenic neurodegenerative disorder with an underlying pathology involving the toxic effect of mutant huntingtin protein primarily in striatal and cortical neurons. Phosphodiesterase 10A (PDE10A) regulates intracellular signalling cascades, thus having a key role in promoting neuronal survival. Using positron emission tomography (PET) with [(11)C]IMA107, we investigated the in vivo extra-striatal expression of PDE10A in 12 early premanifest HD gene carriers. Image processing and kinetic modelling was performed using MIAKAT™. Parametric images of [(11)C]IMA107 non-displaceable binding potential (BPND) were generated from the dynamic [(11)C]IMA107 scans using the simplified reference tissue model with the cerebellum as the reference tissue for nonspecific binding. We set a threshold criterion for meaningful quantification of [(11)C]IMA107 BPND at 0.30 in healthy control data; regions meeting this criterion were designated as regions of interest (ROIs). MRI-based volumetric analysis showed no atrophy in ROIs. We found significant differences in mean ROIs [(11)C]IMA107 BPND between HD gene carriers and healthy controls. HD gene carriers had significant loss of PDE10A within the insular cortex and occipital fusiform gyrus compared to healthy controls. Insula and occipital fusiform gyrus are important brain areas for the regulation of cognitive and limbic function that is impaired in HD. Our findings suggest that dysregulation of PDE10A-mediated intracellular signalling could be an early phenomenon in the course of HD with relevance also for extra-striatal brain areas. PMID:27538642

  14. An HD-domain phosphodiesterase mediates cooperative hydrolysis of c-di-AMP to affect bacterial growth and virulence

    Huynh, TuAnh Ngoc; Luo, Shukun; Pensinger, Daniel; Sauer, John-Demian; Tong, Liang; Woodward, Joshua J.

    2015-01-01

    The nucleotide cyclic di-3′,5′- adenosine monophosphate (c-di-AMP) was recently identified as an essential and widespread second messenger in bacterial signaling. Among c-di-AMP–producing bacteria, altered nucleotide levels result in several physiological defects and attenuated virulence. Thus, a detailed molecular understanding of c-di-AMP metabolism is of both fundamental and practical interest. Currently, c-di-AMP degradation is recognized solely among DHH-DHHA1 domain-containing phosphodiesterases. Using chemical proteomics, we identified the Listeria monocytogenes protein PgpH as a molecular target of c-di-AMP. Biochemical and structural studies revealed that the PgpH His-Asp (HD) domain bound c-di-AMP with high affinity and specifically hydrolyzed this nucleotide to 5′-pApA. PgpH hydrolysis activity was inhibited by ppGpp, indicating a cross-talk between c-di-AMP signaling and the stringent response. Genetic analyses supported coordinated regulation of c-di-AMP levels in and out of the host. Intriguingly, a L. monocytogenes mutant that lacks c-di-AMP phosphodiesterases exhibited elevated c-di-AMP levels, hyperinduced a host type-I IFN response, and was significantly attenuated for infection. Furthermore, PgpH homologs, which belong to the 7TMR-HD family, are widespread among hundreds of c-di-AMP synthesizing microorganisms. Thus, PgpH represents a broadly conserved class of c-di-AMP phosphodiesterase with possibly other physiological functions in this crucial signaling network. PMID:25583510

  15. Selective inhibition of purified human phosphodiesterase 4A expressed in yeast cell GL62 by ciclamilast, piclamilast, and rolipram

    Jun-chun CHEN; Ji-qiang CHEN; Qiang-min Xie; Yi-liang ZHU

    2004-01-01

    AIM: To improve the specific activity of human phosphodiesterase 4A (PDE4A) expressed in yeast cell GL62 and investigate the effects of selective phosphodiesterase 4 (PDE4) inhibitors (ciclamilast, piclamilast, and rolipram),selective phosphodiesterase 5 (PDES) inhibitor zaprinast, and cyclooxygenase (COX) inhibitors (aspirin, indomethacin)on human PDE4A activity expressed in yeast cell GL62. METHODS: Human PDE4A was expressed in yeast cell GL62 after CuSO4 induction and the specific activity of human PDE4A was improved by ammonium sulfate fractionation, DEAE Sephadex A-50 chromatography, and Sephadex G-100 chromatography. The activity of PDE4A was measured by high performance liquid chromatography (HPLC). RESULTS: Induced PDE4A activity expressed in crude yeast cell GL62 supernatant and pellet was (340±21) nmol.g-1.min-1 and (250±25) nmol.g-1.min-lrespectively. The specific activity of recombinant PDE4A in supernatant was improved 6.4 fold. Ciclamilast,piclamilast, and rolipram could inhibit PDE4A activity. The ICs0 values (95 % confidence limits) of ciclamilast,piclamilast, and rolipram were 1.27 (0.84-1.91), 66.4 (33.3-132.2), and 3.73 (2.51-5.53) μmol/L respectively.Zaprinast, aspirin, and indomethacin had no obvious inhibitory effect on PDE4A activity. CONCLUSION: The specific activity of PDE4A expressed in yeast cell GL62 can be improved by ammonium sulfate fractionation,DEAE Sephadex A-50 chromatography, and Sephadex G-100 chromatography. Ciclamilast, piclamilast, and rolipram can inhibit PDE4A activity while zaprinast, aspirin, and indomethacin have no obvious inhibitory effect on PDE4A activity. Human PDE4A expressed in GL62 might be useful in the research and screening of new selective PDE4 inhibitors.

  16. Phosphatidylinositol-specific phospholipase C from Bacillus cereus combines intrinsic phosphotransferase and cyclic phosphodiesterase activities: A 31P NMR study

    The inositol phosphate products formed during the cleavage of phosphatidylinositol by phosphatidylinositol-specific phospholipase C from Bacillus cereus were analyzed by 31P NMR. 31P NMR spectroscopy can distinguish between the inositol phosphate species and phosphatidylinositol. Chemical shift values (with reference to phosphoric acid) observed are -0.41, 3.62, 4.45, and 16.30 ppm for phosphatidylinositol, myo-inositol 1-monophosphate, myo-inositol 2-monophosphate, and myo-inositol 1,2-cyclic monophosphate, respectively. It is shown that under a variety of experimental conditions this phospholipase C cleaves phosphatidylinositol via an intramolecular phosphotransfer reaction producing diacylglycerol and D-myo-inositol 1,2-cyclic monophosphate. The authors also report the new and unexpected observation that the phosphatidylinositol-specific phospholipase C from B. cereus is able to hydrolyze the inositol cyclic phosphate to form D-myo-inositol 1-monophosphate. The enzyme, therefore, possesses phosphotransferase and cyclic phosphodiesterase activities. The second reaction requires thousandfold higher enzyme concentrations to be observed by 31P NMR. This reaction was shown to be regiospecific in that only the 1-phosphate was produced and stereospecific in that only D-myo-inositol 1,2-cyclic monophosphate was hydrolyzed. Inhibition with a monoclonal antibody specific for the B.cereus phospholipase C showed that the cyclic phosphodiesterase activity is intrinsic to the bacterial enzyme. They propose a two-step mechanism for the phosphatidyl-inositol-specific phospholipase C from B. cereus involving sequential phosphotransferase and cyclic phosphodiesterase activities. This mechanism bears a resemblance to the well-known two-step mechanism of pancreatic ribonuclease, RNase A

  17. Incidence rate of prostate cancer in men treated for erectile dysfunction with phosphodiesterase type 5 inhibitors: retrospective analysis

    Chavez, Anthony H; Scott Coffield, K; Hasan Rajab, M; Jo, Chanhee

    2013-01-01

    The purpose of this study was to determine the incidence rate of prostate cancer among men with erectile dysfunction (ED) treated with phosphodiesterase type 5 inhibitors (PDE-5i) over a 7-year period vs. men with ED of the same age and with similar risk factors who were not treated with PDE-5i. In a retrospective review of electronic medical records and billing databases between the years 2000 and 2006, men with ED between the ages of 50 and 69 years and no history of prostate cancer prior t...

  18. Structural basis of phosphodiesterase 6 inhibition by the C-terminal region of the γ-subunit

    Barren, Brandy; Gakhar, Lokesh; Muradov, Hakim; Boyd, Kimberly K.; Ramaswamy, S; Artemyev, Nikolai O.

    2009-01-01

    The inhibitory interaction of phosphodiesterase-6 (PDE6) with its γ-subunit (Pγ) is pivotal in vertebrate phototransduction. Here, crystal structures of a chimaeric PDE5/PDE6 catalytic domain (PDE5/6cd) complexed with sildenafil or 3-isobutyl-1-methylxanthine and the Pγ-inhibitory peptide Pγ70−87 have been determined at 2.9 and 3.0 Å, respectively. These structures show the determinants and the mechanism of the PDE6 inhibition by Pγ and suggest the conformational change of Pγ on transducin ac...

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

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

    2015-01-01

    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......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...

  20. Conditions that alter intracellular cAMP levels affect expression of the cAMP phosphodiesterase gene in Dictyostelium.

    Riley, B B; Barclay, S L

    1990-01-01

    We examined expression of the Dictyostelium cAMP phosphodiesterase (PDE) gene under conditions that alter intracellular cAMP levels during in vitro differentiation of wild-type strain V12M2 and a sporogenous derivative, HB200. In control cultures, cellular PDE activity peaked at 6 hr and declined by 8 hr, while secreted PDE activity continued to increase through 8 hr. Lowering intracellular cAMP levels with caffeine or progesterone increased cellular and secreted PDE activities 2-fold, increa...

  1. Phosphodiesterases 3 and 5 express activity in the trigeminal ganglion and co-localize with calcitonin gene-related peptide

    Nordgaard, Julie C; Kruse, Lars S; Møller, Morten; Kruuse, Christina

    2014-01-01

    Understanding of the neuropathology leading to migraine pain has centered on either a vascular or neuronal origin. Sildenafil, a specific inhibitor of phosphodiesterase 5 (PDE5), induces migraine-like headache in a human headache model without concomitant artery dilation. The presence and activit...... of PDE3 and PDE5 is known in cerebral arteries. However, the presence in the neuronal part of the trigeminovascular pathway, i.e. the trigeminal ganglion and the possible co-localization with calcitonin gene-related peptide (CGRP), is not known....

  2. Phosphodiesterase 5a Inhibition with Adenoviral Short Hairpin RNA Benefits Infarcted Heart Partially through Activation of Akt Signaling Pathway and Reduction of Inflammatory Cytokines

    Li, Longhu; Zhao, Dong; Jin, Zhe; Zhang, Jian; Paul, Christian; Wang, Yigang

    2015-01-01

    Introduction Treatment with short hairpin RNA (shRNA) interference therapy targeting phosphodiesterase 5a after myocardial infarction (MI) has been shown to mitigate post-MI heart failure. We investigated the mechanisms that underpin the beneficial effects of PDE5a inhibition through shRNA on post-MI heart failure. Methods An adenoviral vector with an shRNA sequence inserted was adopted for the inhibition of phosphodiesterase 5a (Ad-shPDE5a) in vivo and in vitro. Myocardial infarction (MI) wa...

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

    Riess, O; Noerremoelle, A; Weber, B; Musarella, M A; Hayden, M R

    1992-01-01

    including 196 bp of the 5' region of the PDEB gene have been assessed for mutations by using single-strand conformational polymorphism analysis in 14 patients from 13 unrelated families with autosomal recessive retinitis pigmentosa (ARRP). No disease-causing mutations were found in this group of affected......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...

  4. Cytochemical demonstration of cyclic 3', 5' AMP phosphodiesterase in different tissue of migratory locust (Locusta migratoria migratorioides R.F.).

    Benedeczky, I; Rózsa, K S

    1981-01-01

    The localization of cyclic 3', 5'-AMP phosphodiesterase was studied by ultrastructural cytochemical methods in the various tissues of Locusta migratoria. Large amounts of electron dense, granular reaction products were detectable on the surface of the corpora allata and the corpus cardiacum, bound to the basal lamina. In the protocerebral neuropile rather large amounts of reaction products were observed in the processes of the glial cells. A significant number of lead phosphate deposit was found to occur on the membrane of certain large axons, the microtubules of the axons, furthermore on the membrane of several terminals. Reaction product was also observable in certain terminals, bound to the synaptic vesicles and the mitochondria. At the same time, electron dense deposits were not detectable at all on the surface of cerebral neurons. In the case of myocardium, reaction product was only found on the basal lamina and the extracellular surface of the sarcolemma. On the basis of our results it can be stated that the cyclic 3', 5'-AMP phosphodiesterase is detectable by cytochemical methods in different tissues of Locusta migratoria and presumably it fulfils the task of the extracellular cAMP level regulation. PMID:6260713

  5. Depletion of tyrosyl DNA phosphodiesterase 2 activity enhances etoposide-mediated double-strand break formation and cell killing.

    Kont, Yasemin Saygideger; Dutta, Arijit; Mallisetty, Apurva; Mathew, Jeena; Minas, Tsion; Kraus, Christina; Dhopeshwarkar, Priyanka; Kallakury, Bhaskar; Mitra, Sankar; Üren, Aykut; Adhikari, Sanjay

    2016-07-01

    DNA topoisomerase 2 (Top2) poisons, including common anticancer drugs etoposide and doxorubicin kill cancer cells by stabilizing covalent Top2-tyrosyl-DNA 5'-phosphodiester adducts and DNA double-strand breaks (DSBs). Proteolytic degradation of the covalently attached Top2 leaves a 5'-tyrosylated blocked termini which is removed by tyrosyl DNA phosphodiesterase 2 (TDP2), prior to DSB repair through non-homologous end joining (NHEJ). Thus, TDP2 confers resistance of tumor cells to Top2-poisons by repairing such covalent DNA-protein adducts, and its pharmacological inhibition could enhance the efficacy of Top2-poisons. We discovered NSC111041, a selective inhibitor of TDP2, by optimizing a high throughput screening (HTS) assay for TDP2's 5'-tyrosyl phosphodiesterase activity and subsequent validation studies. We found that NSC111041 inhibits TDP2's binding to DNA without getting intercalated into DNA and enhanced etoposide's cytotoxicity synergistically in TDP2-expressing cells but not in TDP2 depleted cells. Furthermore, NSC111041 enhanced formation of etoposide-induced γ-H2AX foci presumably by affecting DSB repair. Immuno-histochemical analysis showed higher TDP2 expression in a sub-set of different type of tumor tissues. These findings underscore the feasibility of clinical use of suitable TDP2 inhibitors in adjuvant therapy with Top2-poisons for a sub-set of cancer patients with high TDP2 expression. PMID:27235629

  6. Phosphodiesterase 5 inhibitors prevent 3,4-methylenedioxymethamphetamine-induced 5-HT deficits in the rat.

    Puerta, Elena; Hervias, Isabel; Goñi-Allo, Beatriz; Lasheras, Berta; Jordan, Joaquin; Aguirre, Norberto

    2009-02-01

    Phosphodiesterase 5 (PDE5) inhibitors are often used in combination with club drugs such as 3,4-methylenedioxymethamphetamine (MDMA or ecstasy). We investigated the consequences of such combination in the serotonergic system of the rat. Oral administration of sildenafil citrate (1.5 or 8 mg/kg) increased brain cGMP levels and protected in a dose-dependent manner against 5-hydroxytryptamine depletions caused by MDMA (3 x 5 mg/kg, i.p., every 2 h) in the striatum, frontal cortex and hippocampus without altering the acute hyperthermic response to MDMA. Intrastriatal administration of the protein kinase G (PKG) inhibitor, KT5823 [(9S, 10R, 12R)-2,3,9,10,11,12-Hexahydro-10-methoxy-2,9-dimethyl-1-oxo-9,12-epoxy-1H-diindolo[1,2,3-fg:3',2',1'-kl]pyrrolo[3,4-i][1,6]benzodiazocine-10-carboxylic acid, methyl ester)], suppressed sildenafil-mediated protection. By contrast, the cell permeable cGMP analogue, 8-bromoguanosine cyclic 3',5'-monophosphate, mimicked sildenafil effects further suggesting the involvement of the PKG pathway in mediating sildenafil protection. Because mitochondrial ATP-sensitive K(+) channels are a target for PKG, we next administered the specific mitochondrial ATP-sensitive K(+) channel blocker, 5-hydroxydecanoic acid, 30 min before sildenafil. 5-hydroxydecanoic acid completely reversed the protection afforded by sildenafil, thereby implicating the involvement of mitochondrial ATP-sensitive K(+) channels. Sildenafil also increased Akt phosphorylation, and so the possible involvement of the Akt/endothelial nitric oxide synthase (eNOS)/sGC signalling pathway was analysed. Neither the phosphatidylinositol 3-kinase inhibitor, wortmannin, nor the selective eNOS inhibitor, L-N5-(1-iminoethyl)-L-ornithine dihydrochloride, reversed the protection afforded by sildenafil, suggesting that Akt/eNOS/sGC cascade does not participate in the protective mechanisms. Our data also show that the protective effect of sildenafil can be extended to vardenafil, another PDE5

  7. Effects of phosphodiesterase 4 inhibition on bleomycin-induced pulmonary fibrosis in mice

    Ghofrani Hossein A

    2010-05-01

    Full Text Available Abstract Background Pulmonary fibrosis (PF is a group of devastating and largely irreversible diseases. Phosphodiesterase (PDE 4 is involved in the processes of remodeling and inflammation, which play key role in tissue fibrosis. The aim of the study was, therefore, to investigate the effect of PDE4 inhibition in experimental model of PF. Methods PF was induced in C57BL/6N mice by instillation of bleomycin. Pharmacological inhibition of PDE4 was achieved by using cilomilast, a selective PDE4 inhibitor. Changes in either lung inflammation or remodeling were evaluated at different stages of experimental PF. Lung inflammation was assessed by bronchoalveolar lavage fluid (BALF differential cell count and reverse transcription quantitative polymerase chain reaction (RT-qPCR for inflammatory cytokines. Changes in tissue remodeling were evaluated by pulmonary compliance measurement, quantified pathological examination, measurement of collagen deposition and RT-qPCR for late remodeling markers. Survival in all groups was analyzed as well. Results PDE4 inhibition significantly reduced the total number of alveolar inflammatory cells in BALF of mice with bleomycin-induced PF at early fibrosis stage (days 4 and 7. Number of macrophages and lymphocytes, but not neutrophils, was significantly reduced as well. Treatment decreased lung tumor necrosis factor (TNF-α mRNA level and increased mRNA level of interleukin (IL-6 but did not influence IL-1β. At later stage (days 14 and 24 cilomilast improved lung function, which was shown by increase in lung compliance. It also lowered fibrosis degree, as was shown by quantified pathological examination of Hematoxilin-Eosin stained lung sections. Cilomilast had no significant effect on the expression of late remodeling markers such as transforming growth factor (TGF-β1 and collagen type Ia1 (COL(Iα1. However, it tended to restore the level of lung collagen, assessed by SIRCOL assay and Masson's trichrome staining

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

    Kucka, Marek [Section on Cellular Signaling, Program in Developmental Neuroscience, NICHD, NIH, Bethesda, MD (United States); Pogrmic-Majkic, Kristina; Fa, Svetlana [Laboratory for Ecotoxicology, Department of Biology and Ecology, University of Novi Sad, Faculty of Sciences, 21000 Novi Sad (Serbia); Stojilkovic, Stanko S. [Section on Cellular Signaling, Program in Developmental Neuroscience, NICHD, NIH, Bethesda, MD (United States); Kovacevic, Radmila, E-mail: radmila.kovacevic@dbe.uns.ac.rs [Laboratory for Ecotoxicology, Department of Biology and Ecology, University of Novi Sad, Faculty of Sciences, 21000 Novi Sad (Serbia)

    2012-11-15

    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

  9. Effects of phosphodiesterase 5 inhibitors on sperm parameters and fertilizing capacity

    F. Dimitriadis; I. Georgiou; M. Saito; T. Watanabe; I. Miyagawa; N. Sofikitis; D. Giannakis; N. Pardalidis; K. Zikopoulos; E. Paraskevaidis; N. Giotitsas; V. Kalaboki; P. Tsounapi; D. Baltogiannis

    2008-01-01

    The aim of this review study is to elucidate the effects that phosphodiesterase 5 (PDE5) inhibitors exert on spermatozoa motility, capacitation process and on their ability to fertilize the oocyte. Second messenger systems such as the cAMP/adenylate cyclase (AC) system and the cGMP/guanylate cyclase (GC) system appear to regulate sperm functions. Increased levels of intracytosolic cAMP result in an enhancement of sperm motility and viability.The stimulation of GC by low doses of nitric oxide (NO) leads to an improvement or maintenance of sperm motility,whereas higher concentrations have an adverse effect on sperm parameters. Several in vivo and in vitro studies have been carried out in order to examine whether PDE5 inhibitors affect positively or negatively sperm parameters and sperm fertilizing capacity. The results of these studies are controversial. Some of these studies demonstrate no significant effects of PDE5 inhibitors on the motility, viability, and morphology of spermatozoa collected from men that have been treated with PDE5 inhibitors. On the other hand, several studies demonstrate a positive effect of PDE5 inhibitors on sperm motility both in vivo and in vitro. In vitro studies of sildenafil citrate demonstrate a stimulatory effect on sperm motility with an increase in intracellular cAMP suggesting an inhibitory action of sildenafil citrate on a PDE isoform other than the PDE5. On the other hand, tadalafil's actions appear to be associated with the inhibitory effect of this compound on PDE11. In vivo studies in men treated with vardenafil in a daily basis demonstrated a significantly larger total number of spermatozoa per ejaculate, quantitative sperm motility, and qualitative sperm motility; it has been suggested that vardenafil administration enhances the secretory function of the prostate and subsequently increases the qualitative and quantitative motility of spermatozoa. The effect that PDE5 inhibitors exert on sperm parameters may lead to the

  10. Sex-differential genetic effect of phosphodiesterase 4D (PDE4D on carotid atherosclerosis

    Guo Yuh-Cherng

    2010-06-01

    Full Text Available Abstract Background The phosphodiesterase 4D (PDE4D gene was reported as a susceptibility gene to stroke. The genetic effect might be attributed to its role in modulating the atherogenic process in the carotid arteries. Using carotid intima-media thickness (IMT and plaque index as phenotypes, the present study sought to determine the influence of this gene on subclinical atherosclerosis. Methods Carotid ultrasonography was performed on 1013 stroke-free subjects who participated in the health screening programs (age 52.6 ± 12.2; 47.6% men. Genotype distribution was compared among the high-risk (plaque index ≥ 4, low-risk (index = 1-3, and reference (index = 0 groups. We analyzed continuous IMT data and further dichotomized IMT data using mean plus one standard deviation as the cutoff level. Because the plaque prevalence and IMT values displayed a notable difference between men and women, we carried out sex-specific analyses in addition to analyzing the overall data. Rs702553 at the PDE4D gene was selected because it conferred a risk for young stroke in our previous report. Previous young stroke data (190 cases and 211 controls with an additional 532 control subjects without ultrasonic data were shown as a cross-validation for the genetic effect. Results In the overall analyses, the rare homozygote of rs702553 led to an OR of 3.1 (p = 0.034 for a plaque index ≥ 4. When subjects were stratified by sex, the genetic effect was only evident in men but not in women. Comparing male subjects with plaque index ≥ 4 and those with plaque index = 0, the TT genotype was over-represented (27.6% vs. 13.4%, p = 0.008. For dichotomized IMT data in men, the TT genotype had an OR of 2.1 (p = 0.032 for a thicker IMT at the common carotid artery compared with the (AA + AT genotypes. In women, neither IMT nor plaque index was associated with rs702553. Similarly, SNP rs702553 was only significant in young stroke men (OR = 1.8, p = 0.025 but not in women (p = 0

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

    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

  12. COVER FIGURE in Nucleic Acids Research (Volume 39, Issue 9) entitled "The involvement of the nuclear-encoded human 2'-phosphodiesterase in mitochondrial RNA turnover"

    Poulsen, Jesper Buchhave

    2011-01-01

    (English) Cover: The involvement of the nuclear-encoded human 2'-phosphodiesterase (2'-PDE) in mitochondrial RNA turnover. The 2'-PDE precursor (upper left corner) gets directed into the mitochondrial matrix by an N-terminal mitochondrial signaling peptide (blue). Inside the matrix, this signaling...

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

    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 ostatní: 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: 2.503, year: 2014

  14. Uncovering the function of Disrupted in Schizophrenia 1 through interactions with the cAMP phosphodiesterase PDE4: Contributions of the Houslay lab to molecular psychiatry.

    Brandon, Nicholas J

    2016-07-01

    Nearly 10years ago the laboratory of Miles Houslay was part of a collaboration which identified and characterized the interaction between Disrupted in Schizophrenia 1 and phosphodiesterase type 4. This work has had significant impact on our thinking of psychiatric illness causation and the potential for therapeutics. PMID:26432168

  15. Insights into the regulation of TNF-a production in human mononuclear cells: the effects of non-specific phosphodiesterase inhibition

    Jessica Deree

    2008-01-01

    Full Text Available OBJECTIVE: The objective of this study was to determine the effect of nonspecific phosphodiesterase inhibition on transcription factor activation and tumor necrosis factor-alpha (TNF-a production in lipopolysaccharide (LPS-stimulated human mononuclear cells. INTRODUCTION: The production of TNF-a following LPS stimulation is one of the key steps in bacterial sepsis and inflammation. The mechanism by which phosphodiesterase inhibition alters TNF-a production in the presence of LPS remains unclear. METHODS: Human mononuclear cells were stimulated with LPS (1 µg/mL, in the presence and absence of Pentoxifylline (PTX; 20 mM, a nonspecific phosphodiesterase inhibitor. Western blotting of phosphorylated cytoplasmic I-kBa, nuclear factor-kB p65 (NF-kB, and nuclear cAMP-response element binding protein (CREB was performed. DNA binding of NF-kB and CREB was verified by electrophoretic mobility shift assay. TNF-a levels were determined in the supernatant of stimulated cells in the presence and absence Protein kinase A inhibition by an enzyme-linked immunosorbent assay (ELISA. RESULTS: PTX was demonstrated to significantly reduce cytoplasmic I-kBa phosphorylation, nuclear p65 phosphorylation, and the DNA binding activity of NF-kB. In contrast, PTX markedly enhanced the phosphorylation and DNA binding activity of CREB. Cells concomitantly treated with PTX and LPS secreted similar levels of TNF-a in the presence and absence Protein kinase A inhibition. DISCUSSION: The increased level of cAMP that results from phosphodiesterase inhibition affects cytoplasmic and nuclear events, resulting in the attenuation of NF-kB and the activation of CREB transcriptional DNA binding through pathways that are partially Protein kinase A-independent. CONCLUSION: PTX-mediated phosphodiesterase inhibition occurs partially through a Protein kinase A-independent pathway and may serve as a useful tool in the attenuation of LPS-induced inflammation.

  16. One step N-glycosylation by filamentous fungi biofilm in bioreactor of a new phosphodiesterase-3 inhibitor tetrazole.

    de Melo Souza, Paula L; Arruda, Evilanna L; Pazini, Francine; Menegatti, Ricardo; Vaz, Boniek G; Lião, Luciano M; de Oliveira, Valéria

    2016-07-01

    An efficient and rapid process for N-glycosylation of 5-(1-(3-fluorophenyl)-1H-pyrazol-4-yl)-2H-tetrazole-LQFM 021 (1), a new synthetic derivative of pyrazole with phosphodiesterase-3 (PDE-3) inhibitory action, vasorelaxant activity and low toxicity catalyzed by filamentous fungi biofilm in bioreactor was successfully developed. A maximum N-glycosyl yield of 68% was obtained with Cunninghamella echinulata ATCC 9244 biofilm in bioreactor with conditions of 25mgml(-1) of 1 in PDSM medium at 28°C for 96h. After extraction with ethyl acetate, the derivative was identified by Ultrahigh Resolution Mass Spectrometry and (1)H-(13)C HSQC/HMBC. PMID:27209234

  17. Discovery of selective inhibitors of tyrosyl-DNA phosphodiesterase 2 by targeting the enzyme DNA-binding cleft.

    Kossmann, Bradley R; Abdelmalak, Monica; Lopez, Sophia; Tender, Gabrielle; Yan, Chunli; Pommier, Yves; Marchand, Christophe; Ivanov, Ivaylo

    2016-07-15

    Tyrosyl-DNA phosphodiesterase 2 (TDP2) processes protein/DNA adducts resulting from abortive DNA topoisomerase II (Top2) activity. TDP2 inhibition could provide synergism with the Top2 poison class of chemotherapeutics. By virtual screening of the NCI diversity small molecule database, we identified selective TDP2 inhibitors and experimentally verified their selective inhibitory activity. Three inhibitors exhibited low-micromolar IC50 values. Molecular dynamics simulations revealed a common binding mode for these inhibitors, involving association to the TDP2 DNA-binding cleft. MM-PBSA per-residue energy decomposition identified important interactions of the compounds with specific TDP2 residues. These interactions could provide new avenues for synthetic optimization of these scaffolds. PMID:27262595

  18. Switching from nitrate therapy to ranolazine in patients with coronary artery disease receiving phosphodiesterase type-5 inhibitors for erectile dysfunction.

    Udeoji, Dioma U; Schwarz, Ernst R

    2014-01-01

    Coronary artery disease (CAD) and erectile dysfunction (ED) frequently coexist. The introduction of phosphodiesterase type-5 (PDE-5) inhibitors has revolutionized medical management of organic ED; however, in patients with angina pectoris, a common symptom of CAD, coadministration of PDE-5 inhibitors and nitrates has been implicated in CAD-related deaths following sexual activity. The mechanism of action of PDE-5 inhibitors results in a potential cumulative drop in blood pressure (BP); thus, these agents are contraindicated in patients receiving nitrates. Beta-blockers and calcium channel antagonists are considered the mainstays of antianginal therapy, but may not be tolerated by all patients. Ranolazine is an antianginal agent that produces minimal reductions in heart rate and BP. Here we report three cases of men with CAD, chronic angina, and concomitant ED. We describe our treatment approach in these patients, using ranolazine as a potential substitute to nitrate therapy. PMID:25452706

  19. Decreased permeability surface area for glucose in obese women with postprandial hyperglycemia: no effect of phosphodiesterase-5 (PDE-5) inhibition.

    Sandqvist, M; Strindberg, L; Lönnroth, P; Jansson, P-A

    2013-08-01

    Insulin-mediated microvascular recruitment is recognized as a potential mechanism contributing to insulin resistance. In this study, we compared a marker of microvascular function, the permeability surface area for glucose (PS(glu)), and forearm glucose uptake after an OGTT in obese women with impaired glucose metabolism and healthy lean nondiabetic women, with the aim to characterize whether decreased permeability surface area for glucose or decreased glucose uptake may contribute to postprandial hyperglycemia in the obese group. In addition, we evaluated whether the phosphodiesterase-5 (PDE-5) inhibitor tadalafil, in a randomized double blind placebo controlled design, might attenuate postprandial glucose levels in obese women. For these purposes, intramuscular microdialysis, blood sampling from arterial and venous blood of the forearm, and measurements of forearm blood flow were performed. The results showed an impaired permeability surface area for glucose (IAUC PS(glu) 31±13 vs. 124±31; pPDE-5) inhibitor tadalafil. PMID:23613014

  20. Acute effect of phosphodiesterase type 5 inhibitor on serum oxidative status and prolidase activities in men with erectile dysfunction

    Murat Savas

    2010-01-01

    Full Text Available OBJECTIVES: To investigate the acute effect of phosphodiesterase type 5 (PDE5 inhibitor on erectile dysfunction by evaluating serum oxidative status and prolidase activity. METHODS: Serum samples of 36 patients with erectile dysfunction and 30 control cases were analyzed for total antioxidant status, total oxidant status, and prolidase activity, before and after the administration of tadalafil citrate. RESULTS: Before and after tadalafil citrate administration, serum total antioxidant status, total oxidant status, and prolidase were 1.1+0.0 vs. 1.6 + 0.0 umol H2O2 Eq/L, 10.3+1.1 vs. 6.9 + 1.2 umol H2O2 Eq/L, and 236.4+19.5 vs. 228.2 + 19.2 U/L, respectively (p<0.0001 for all. CONCLUSIONS: Evaluation of serum oxidative status and prolidase activity confirmed the beneficial acute effects of PDE5 inhibitor in patients with erectile dysfunction.

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

    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. Conformational Variations of Both Phosphodiesterase-5 and Inhibitors Provide the Structural Basis for the Physiological Effects of Vardenafil and Sildenafil

    Wang, H.; Ye, M; Robinson, H; Fransis, S; Ke, H

    2007-01-01

    Vardenafil has higher affinity to phosphodiesterase-5 (PDE5) than sildenafil and lower administered dosage for the treatment of erectile dysfunction. However, the molecular basis for these differences is puzzling because two drugs have similar chemical structures. Reported here is a crystal structure of the fully active and nonmutated PDE5A1 catalytic domain in complex with vardenafil. The structure shows that the conformation of the H-loop in the PDE5A1-vardenafil complex is different from those of any known structures of the unliganded PDE5 and its complexes with the inhibitors. In addition, the molecular configuration of vardenafil differs from that of sildenafil when bound to PDE5. It is noteworthy that the binding of vardenafil causes loss of the divalent metal ions that have been observed in all the previously published PDE structures. The conformational variation of both PDE5 and the inhibitors provides structural insight into the different potencies of the drugs.

  3. Conformational Variations of Both Phosphodiesterase-5 and Inhibitors Provide the Structural Basis for the Physiological Effects of Verdenafil and Sildenafil

    Wang,H.; Ye, M.; Robinson, H.; Francis, S.; Ke, H.

    2008-01-01

    Vardenafil has higher affinity to phosphodiesterase-5 (PDE5) than sildenafil and lower administered dosage for the treatment of erectile dysfunction. However, the molecular basis for these differences is puzzling because two drugs have similar chemical structures. Reported here is a crystal structure of the fully active and nonmutated PDE5A1 catalytic domain in complex with vardenafil. The structure shows that the conformation of the H-loop in the PDE5A1-vardenafil complex is different from those of any known structures of the unliganded PDE5 and its complexes with the inhibitors. In addition, the molecular configuration of vardenafil differs from that of sildenafil when bound to PDE5. It is noteworthy that the binding of vardenafil causes loss of the divalent metal ions that have been observed in all the previously published PDE structures. The conformational variation of both PDE5 and the inhibitors provides structural insight into the different potencies of the drugs.

  4. Increased Activity of cGMP-Specific Phosphodiesterase (PDE5) Contributes to Resistance to Atrial Natriuretic Peptide Natriuresis in the Pregnant Rat

    Ni, Xi-Ping; SAFAI, MASSY; Rishi, Rahul; Baylis, Chris; Humphreys, Michael H.

    2004-01-01

    Increased cGMP-specific phosphodiesterase (PDE5) activity in renal inner medullary collecting duct (IMCD) cells contributes to resistance to atrial natriuretic peptide (ANP) and the excessive sodium retention seen in experimental nephrotic syndrome and liver cirrhosis. Normal pregnancy is also accompanied by sodium retention and plasma volume expansion, and pregnant rats are resistant to the natriuretic action of ANP. The authors investigated a possible role of increased renal PDE5 activity i...

  5. Distinct Allostery Induced in the Cyclic GMP-binding, Cyclic GMP-specific Phosphodiesterase (PDE5) by Cyclic GMP, Sildenafil, and Metal Ions*

    Biswas, Kabir H.; Visweswariah, Sandhya S.

    2010-01-01

    The activity of many proteins orchestrating different biological processes is regulated by allostery, where ligand binding at one site alters the function of another site. Allosteric changes can be brought about by either a change in the dynamics of a protein, or alteration in its mean structure. We have investigated the mechanisms of allostery induced by chemically distinct ligands in the cGMP-binding, cGMP-specific phosphodiesterase, PDE5. PDE5 is the target for catalytic site inhibitors, s...

  6. Phosphodiesterase-5 activity exerts a coronary vasoconstrictor influence in awake swine that is mediated in part via an increase in endothelin production

    Zhou, Zhichao; de Beer, Vincent J.; Bender, Shawn B.; Jan Danser, A. H.; Merkus, Daphne; Laughlin, M. Harold; Duncker, Dirk J

    2014-01-01

    Nitric oxide (NO)-induced coronary vasodilation is mediated through production of cyclic guanosine monophosphate (cGMP) and through inhibition of the endothelin-1 (ET) system. We previously demonstrated that phosphodiesterase-5 (PDE5)-mediated cGMP breakdown and ET each exert a vasoconstrictor influence on coronary resistance vessels. However, little is known about the integrated control of coronary resistance vessel tone by these two vasoconstrictor mechanisms. In the present study, we inves...

  7. Phosphodiesterase type 5 inhibitors for treating erectile dysfunction and lower urinary tract symptoms secondary to benign prostatic hyperplasia: A comprehensive review

    Haddad, Albert; Jabbour, Michel; Bulbul, Muhammad

    2015-01-01

    Many men have coexistent erectile dysfunction (ED) and lower urinary tract symptoms secondary to benign prostatic hyperplasia (LUTS/BPH). Phosphodiesterase type 5 (PDE5) inhibitors are effective for treating both of these conditions independently. In this review we summarise the evidence supporting a link between ED and LUTS/BPH, and the results from key clinical studies related to the use of PDE5 inhibitors for treating both conditions. The results from these studies suggest that men who hav...

  8. Improvement in duration of erection following phosphodiesterase type 5 inhibitor therapy with vardenafil in men with erectile dysfunction: the ENDURANCE study

    Rosenberg, M. T.; Adams, P L; McBride, T A; Roberts, J N; McCallum, S W

    2009-01-01

    Objective: The ENDURANCE study evaluated the efficacy of vardenafil, a phosphodiesterase type 5 (PDE5) inhibitor, in men with erectile dysfunction (ED), by measuring the duration of erection leading to successful intercourse using a stopwatch as the assessment instrument. Methods: This was a randomised, multicentre, double-blind, placebo-controlled, crossover study consisting of a 4-week treatment-free run-in phase after which patients were randomised to either fixed-dose vardenafil 10 mg or ...

  9. C-di-GMP hydrolysis by Pseudomonas aeruginosa HD-GYP phosphodiesterases: analysis of the reaction mechanism and novel roles for pGpG.

    Valentina Stelitano

    Full Text Available In biofilms, the bacterial community optimizes the strategies to sense the environment and to communicate from cell to cell. A key player in the development of a bacterial biofilm is the second messenger c-di-GMP, whose intracellular levels are modulated by the opposite activity of diguanylate cyclases and phosphodiesterases. Given the huge impact of bacterial biofilms on human health, understanding the molecular details of c-di-GMP metabolism represents a critical step in the development of novel therapeutic approaches against biofilms. In this study, we present a detailed biochemical characterization of two c-di-GMP phosphodiesterases of the HD-GYP subtype from the human pathogen Pseudomonas aeruginosa, namely PA4781 and PA4108. Upstream of the catalytic HD-GYP domain, PA4781 contains a REC domain typical of two-component systems, while PA4108 contains an uncharacterized domain of unknown function. Our findings shed light on the activity and catalytic mechanism of these phosphodiesterases. We show that both enzymes hydrolyse c-di-GMP in a two-step reaction via the linear intermediate pGpG and that they produce GMP in vitro at a surprisingly low rate. In addition, our data indicate that the non-phosphorylated REC domain of PA4781 prevents accessibility of c-di-GMP to the active site. Both PA4108 and phosphorylated PA4781 are also capable to use pGpG as an alternative substrate and to hydrolyse it into GMP; the affinity of PA4781 for pGpG is one order of magnitude higher than that for c-di-GMP. These results suggest that these enzymes may not work (primarily as genuine phosphodiesterases. Moreover, the unexpected affinity of PA4781 for pGpG may indicate that pGpG could also act as a signal molecule in its own right, thus further widening the c-di-GMP-related signalling scenario.

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

    Silvia Elaine Ferreira-Melo; Caroline Demacq; Silvia Lacchini; José Eduardo Krieger; Maria Cláudia Irigoyen; Heitor Moreno

    2011-01-01

    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...

  11. Sildenafil, a phosphodiesterase type 5 inhibitor, enhances the antidepressant activity of amitriptyline but not desipramine, in the forced swim test in mice

    Socała, Katarzyna; Nieoczym, Dorota; Wyska, Elżbieta; Poleszak, Ewa; Wlaź, Piotr

    2012-01-01

    The cholinergic theory of depression highlights the involvement of muscarinic acetylcholine receptors in the neurobiology of mood disorders. The present study was designed to investigate the effect of sildenafil, a phosphodiesterase type 5 inhibitor which exhibits cholinomimetic properties, alone and in combination with scopolamine in the forced swim test in mice. Moreover, we assessed the ability of sildenafil to modify the antidepressant activity of two tricyclic antidepressants with distin...

  12. Surface plasmon resonance biosensor assay for the analysis of small-molecule inhibitor binding to human and parasitic phosphodiesterases.

    Siderius, Marco; Shanmugham, Anitha; England, Paul; van der Meer, Tiffany; Bebelman, Jan Paul; Blaazer, Antoni R; de Esch, Iwan J P; Leurs, Rob

    2016-06-15

    In the past decade, surface plasmon resonance (SPR) biosensor-based technology has been exploited more and more to characterize the interaction between drug targets and small-molecule modulators. Here, we report the successful application of SPR methodology for the analysis of small-molecule binding to two therapeutically relevant cAMP phosphodiesterases (PDEs), Trypanosoma brucei PDEB1 which is implicated in African sleeping sickness and human PDE4D which is implicated in a plethora of disease conditions including inflammatory pulmonary disorders such as asthma, chronic obstructive pulmonary disease and central nervous system (CNS) disorders. A protocol combining the use of directed capture using His-tagged PDE_CDs with covalent attachment to the SPR surface was developed. This methodology allows the determination of the binding kinetics of small-molecule PDE inhibitors and also allows testing their specificity for the two PDEs. The SPR-based assay could serve as a technology platform for the development of highly specific and high-affinity PDE inhibitors, accelerating drug discovery processes. PMID:27033007

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

    Very few tracers are available for imaging studies of second messenger systems. We developed a radiosynthesis for the phosphodiesterase (PDE) 5 inhibitor [11C]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. [11C]RAL-01 readily entered the brain and obtained an equilibrium distribution volume of 4-5 ml g-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, [11C]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

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

    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.

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

    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

    2016-03-01

    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. PMID:25263347

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

    Reeuwijk, N M; Venhuis, B J; de Kaste, D; Hoogenboom, L A P; Rietjens, I M C M; 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 contain APIs that inhibit phosphodiesterase type 5 (PDE-5) inhibitors, such as sildenafil and analogous PDE-5 inhibitors. Herbal food supplements intended to enhance sexual potency (n = 71), and two soft drinks, were sampled from 2003 up to and including 2012. In 23 herbal supplements, nine different PDE-5 inhibitors were identified; in a few cases (n = 3), more than one inhibitor was indentified. The presence of these APIs was however not stated on the label. The concentrations of PDE-5 inhibitors per dose unit were analysed. Furthermore, the potential pharmacologically active properties of the detected PDE-5 inhibitors were estimated by using data from the scientific and patent literature regarding (1) in vitro PDE-5 activity, (2) reported effective doses of registered drugs with PDE-5 inhibitor activity and (3) similarity to other structural analogues. It was concluded that 18 of the 23 herbal food supplements, when used as recommended, would have significant pharmacological effects due to added APIs. Adequate use of existing regulation and control measures seems necessary to protect consumers against the adverse effects of these products. PMID:24261938

  17. Crystal Structure of the Bacillus subtilis Phosphodiesterase PhoD Reveals an Iron and Calcium-containing Active Site♦

    Rodriguez, Fernanda; Lillington, James; Johnson, Steven; Timmel, Christiane R.; Lea, Susan M.; Berks, Ben C.

    2014-01-01

    The PhoD family of extra-cytoplasmic phosphodiesterases are among the most commonly occurring bacterial phosphatases. The exemplars for this family are the PhoD protein of Bacillus subtilis and the phospholipase D of Streptomyces chromofuscus. We present the crystal structure of B. subtilis PhoD. PhoD is most closely related to purple acid phosphatases (PAPs) with both types of enzyme containing a tyrosinate-ligated Fe3+ ion. However, the PhoD active site diverges from that found in PAPs and uses two Ca2+ ions instead of the single extra Fe2+, Mn2+, or Zn2+ ion present in PAPs. The PhoD crystals contain a phosphate molecule that coordinates all three active site metal ions and that is proposed to represent a product complex. A C-terminal helix lies over the active site and controls access to the catalytic center. The structure of PhoD defines a new phosphatase active site architecture based on Fe3+ and Ca2+ ions. PMID:25217636

  18. Photodynamics of blue-light-regulated phosphodiesterase BlrP1 protein from Klebsiella pneumoniae and its photoreceptor BLUF domain

    The BlrP1 protein from the enteric bacterium Klebsiella pneumoniae consists of a BLUF and an EAL domain and may activate c-di-GMP phosphodiesterase by blue-light. The full-length protein, BlrP1, and its BLUF domain, BlrP1BLUF, are characterized by optical absorption and emission spectroscopy. The cofactor FAD in its oxidized redox state (FADox) is brought from the dark-adapted receptor state to the 10-nm red-shifted putative signalling state by violet light exposure. The recovery to the receptor state occurs with a time constant of about 1 min. The quantum yield of signalling state formation is about 0.17 for BlrP1BLUF and about 0.08 for BlrP1. The fluorescence efficiency of the FADox cofactor is small due to photo-induced reductive electron transfer. Prolonged light exposure converts FADox in the signalling state to the fully reduced hydroquinone form FADredH- and causes low-efficient chromophore release with subsequent photo-degradation. The photo-cycle and photo-reduction dynamics in the receptor state and in the signalling state are discussed

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

    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.)

  20. The effect of phosphodiesterase inhibitors on the extinction of cocaine-induced conditioned place preference in mice.

    Liddie, Shervin; Anderson, Karen L; Paz, Andres; Itzhak, Yossef

    2012-10-01

    Several phosphodiesterase inhibitors (PDEis) improve cognition, suggesting that an increase in brain cAMP and cGMP facilitates learning and memory. Since extinction of drug-seeking behavior requires associative learning, consolidation and formation of new memory, the present study investigated the efficacy of three different PDEis in the extinction of cocaine-induced conditioned place preference (CPP) in B6129S mice. Mice were conditioned by escalating doses of cocaine which was resistant to extinction by free exploration. Immediately following each extinction session mice received (a) saline/vehicle, (b) rolipram (PDE4 inhibitor), (c) BAY-73-6691 (PDE9 inhibitor) or (d) papaverine (PDE10A inhibitor). Mice that received saline/vehicle during extinction training showed no reduction in CPP for >10 days. BAY-73-6691 (a) dose-dependently increased cGMP in hippocampus and amygdala, (b) significantly facilitated extinction and (c) diminished the reinstatement of cocaine CPP. Rolipram, which selectively increased brain cAMP levels, and papaverine which caused increases in both cAMP and cGMP levels, had no significant effect on the extinction of cocaine CPP. The results suggest that increase in hippocampal and amygdalar cGMP levels via blockade of PDE9 has a prominent role in the consolidation of extinction learning. PMID:22596207

  1. Inhibition of phosphodiesterase-4 reverses the cognitive dysfunction and oxidative stress induced by Aβ25-35 in rats.

    Zhuo, Yeye; Guo, Haibiao; Cheng, Yufang; Wang, Chuang; Wang, Canmao; Wu, Jingang; Zou, Zhengqiang; Gan, Danna; Li, Yiwen; Xu, Jiangping

    2016-08-01

    Phosphodiesterase-4 (PDE4) inhibitors prevent the breakdown of the second messenger cAMP and have been demonstrated to improve learning in several animal models of cognition. In this study, we explored the antioxidative effects of rolipram in Alzheimer's disease (AD) by using bilateral Aβ25-35 injection into the hippocampus of rats, which were used as an AD model. Rats received 3 intraperitoneal (i.p.) doses of rolipram (0.1, 0.5 and 1.25 mg/kg) daily after the injection of Aβ25-35 for 25 days. Chronic administration of rolipram prevented the memory impairments induced by Aβ25-35, as assessed using the passive avoidance test and the Morris water maze test. Furthermore, rolipram significantly reduced the oxidative stress induced by Aβ25-35, as evidenced by the decrease in the levels of reactive oxygen species (ROS) and malondialdehyde (MDA), and restored the reduced GSH levels and superoxide dismutase (SOD) activity. Moreover, western blotting and real-time reverse transcription polymerase chain reaction (RT-PCR) analysis showed that rolipram remarkably upregulated thioredoxin (Trx) and inhibited the inducible nitric oxide synthase/nitric oxide (iNOS/NO) pathway in the hippocampus. These results demonstrated that rolipram improved the learning and memory abilities in an Aβ25-35-induced AD rat model. The mechanism underlying these effects may be due to the noticeable antioxidative effects of rolipram. PMID:26920899

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

    Evidence of disruptions in cAMP-mediated signaling in several neuropsychiatric disorders has led to the development of R-[11C]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-[11C]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-[11C]Rolipram is thus suitable for imaging PDE4 and possibly cAMP signal transduction in the living human brain with PET. (orig.)

  3. Purification and characterization of bovine lung calmodulin-dependent cyclic nucleotide phosphodiesterase in free and calmodulin-bound forms

    A rabbit lung Ca2+-stimulated cyclic nucleotide phosphodiesterase (PDE) prepared by successive chromatography in the presence of EGTA on DEAE-cellulose and G-200 Sephadex columns still responded to Ca2+ and contained calmodulin (CaM) suggesting that the enzyme exists as a stable CaM-PDE complex. A similar enzyme was demonstrated to exist in bovine lung extract. A monoclonal antibody Cl previously shown to react with the 60 kDa subunit of bovine brain PDE isozymes cross-reacted with the lung enzyme. Purification of the lung enzyme by Cl antibody immunoaffinity chromatography rendered the enzyme dependent of exogenously added CaM for Ca2+ stimulation. The enzyme was further purified by CaM affinity chromatography to near homogeneity. The purified enzyme could be reconstituted into PDE-CaM complex upon incubation with CaM in the presence of either Ca2+ or EGTA. When reconstitution was carried out in the presence of 45Ca2+, followed by isolation of the protein complex, no 45Ca2+ was found to be associated with the complex. CaM antagonists: trifluoroperazine, compound 48/80 and calcineurin at concentrations abolishing CaM-stimulation of bovine brain PDE had little effect on the bovine lung PDE-CaM complex

  4. Mechanism of repair of 5'-topoisomerase II-DNA adducts by mammalian tyrosyl-DNA phosphodiesterase 2

    Schellenberg, Matthew J; Appel, C Denise; Adhikari, Sanjay; Robertson, Patrick D; Ramsden, Dale A; Williams, R Scott [NIH; (Georgetown); (UNC)

    2012-10-28

    The topoisomerase II (topo II) DNA incision-and-ligation cycle can be poisoned (for example following treatment with cancer chemotherapeutics) to generate cytotoxic DNA double-strand breaks (DSBs) with topo II covalently conjugated to DNA. Tyrosyl-DNA phosphodiesterase 2 (Tdp2) protects genomic integrity by reversing 5'-phosphotyrosyl–linked topo II–DNA adducts. Here, X-ray structures of mouse Tdp2–DNA complexes reveal that Tdp2 β–2-helix–β DNA damage–binding 'grasp', helical 'cap' and DNA lesion–binding elements fuse to form an elongated protein-DNA conjugate substrate-interaction groove. The Tdp2 DNA-binding surface is highly tailored for engagement of 5'-adducted single-stranded DNA ends and restricts nonspecific endonucleolytic or exonucleolytic processing. Structural, mutational and functional analyses support a single–metal ion catalytic mechanism for the exonuclease-endonuclease-phosphatase (EEP) nuclease superfamily and establish a molecular framework for targeted small-molecule blockade of Tdp2-mediated resistance to anticancer topoisomerase drugs.

  5. Photodynamics of blue-light-regulated phosphodiesterase BlrP1 protein from Klebsiella pneumoniae and its photoreceptor BLUF domain

    Tyagi, A. [Institut II - Experimentelle und Angewandte Physik, Universitaet Regensburg, Universitaetstrasse 31, D-93053 Regensburg (Germany); Penzkofer, A. [Institut II - Experimentelle und Angewandte Physik, Universitaet Regensburg, Universitaetstrasse 31, D-93053 Regensburg (Germany)], E-mail: alfons.penzkofer@physik.uni-regensburg.de; Griese, J.; Schlichting, I. [Max-Planck-Institut fuer medizinische Forschung, Abteilung Biomolekulare Mechanismen, Jahnstrasse 29, D-69120 Heidelberg (Germany); Kirienko, Natalia V.; Gomelsky, Mark [Department of Molecular Biology, University of Wyoming, Laramie, Wyoming 82071 (United States)

    2008-12-10

    The BlrP1 protein from the enteric bacterium Klebsiella pneumoniae consists of a BLUF and an EAL domain and may activate c-di-GMP phosphodiesterase by blue-light. The full-length protein, BlrP1, and its BLUF domain, BlrP1{sub B}LUF, are characterized by optical absorption and emission spectroscopy. The cofactor FAD in its oxidized redox state (FAD{sub ox}) is brought from the dark-adapted receptor state to the 10-nm red-shifted putative signalling state by violet light exposure. The recovery to the receptor state occurs with a time constant of about 1 min. The quantum yield of signalling state formation is about 0.17 for BlrP1{sub B}LUF and about 0.08 for BlrP1. The fluorescence efficiency of the FAD{sub ox} cofactor is small due to photo-induced reductive electron transfer. Prolonged light exposure converts FAD{sub ox} in the signalling state to the fully reduced hydroquinone form FAD{sub red}H{sup -} and causes low-efficient chromophore release with subsequent photo-degradation. The photo-cycle and photo-reduction dynamics in the receptor state and in the signalling state are discussed.

  6. Photodynamics of blue-light-regulated phosphodiesterase BlrP1 protein from Klebsiella pneumoniae and its photoreceptor BLUF domain

    Tyagi, A.; Penzkofer, A.; Griese, J.; Schlichting, I.; Kirienko, Natalia V.; Gomelsky, Mark

    2008-12-01

    The BlrP1 protein from the enteric bacterium Klebsiella pneumoniae consists of a BLUF and an EAL domain and may activate c-di-GMP phosphodiesterase by blue-light. The full-length protein, BlrP1, and its BLUF domain, BlrP1_BLUF, are characterized by optical absorption and emission spectroscopy. The cofactor FAD in its oxidized redox state (FAD ox) is brought from the dark-adapted receptor state to the 10-nm red-shifted putative signalling state by violet light exposure. The recovery to the receptor state occurs with a time constant of about 1 min. The quantum yield of signalling state formation is about 0.17 for BlrP1_BLUF and about 0.08 for BlrP1. The fluorescence efficiency of the FAD ox cofactor is small due to photo-induced reductive electron transfer. Prolonged light exposure converts FAD ox in the signalling state to the fully reduced hydroquinone form FAD redH - and causes low-efficient chromophore release with subsequent photo-degradation. The photo-cycle and photo-reduction dynamics in the receptor state and in the signalling state are discussed.

  7. Human biodistribution and dosimetry of 18F-JNJ42259152, a radioligand for phosphodiesterase 10A imaging

    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, 18F-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 18F-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 μSv/MBq) and upper large intestine (138 μSv/MBq). The mean effective dose was 24.9 ± 4.1 μSv/MBq. No adverse events were encountered. In humans, 18F-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.)

  8. Inhibition of human cAMP-phosphodiesterase as a mechanism of the spasmolytic effect of Matricaria recutita L.

    Maschi, Omar; Cero, Esther Dal; Galli, Germana V; Caruso, Donatella; Bosisio, Enrica; Dell'Agli, Mario

    2008-07-01

    Mechanisms underlying the spasmolytic activity of chamomile still remain unclear. Inhibition of cAMP- and cGMP-phosphodiesterases (PDE) is one of the mechanisms operated by spasmolytic drugs. In this study, the effect of chamomile on PDE was investigated. Human platelet cAMP-PDE and recombinant PDE5A1 were assayed in the presence of infusions prepared from sifted flowers and capitula. LC-ESI-MS/MS analysis showed different compositions in infusions made with sifted flowers and capitula. Chamomile inhibited cAMP-PDE activity (IC50 = 17.9-40.5 microg/mL), while cGMP-PDE5 was less affected (-15% at 50 microg/mL). Among the individual compounds tested, only flavonoids showed an inhibitory effect (IC50 = 1.3-14.9 microM), contributing to around 39% of the infusion inhibition; other compounds responsible for cAMP-PDE inhibition still remain unknown. Although experimental evidence supporting the use of chamomile for gastrointestinal minor spasms dates back to the fifties, cAMP-PDE inhibition as a likely mechanism underlying the spasmolytic activity is reported for the first time. PMID:18553893

  9. Structural basis of phosphodiesterase 6 inhibition by the C-terminal region of the [gamma]-subunit

    Barren, Brandy; Gakhar, Lokesh; Muradov, Hakim; Boyd, Kimberly K.; Ramaswamy, S.; Artemyev, Nikolai O.; (Iowa)

    2010-03-16

    The inhibitory interaction of phosphodiesterase-6 (PDE6) with its {gamma}-subunit (P{gamma}) is pivotal in vertebrate phototransduction. Here, crystal structures of a chimaeric PDE5/PDE6 catalytic domain (PDE5/6cd) complexed with sildenafil or 3-isobutyl-1-methylxanthine and the P{gamma}-inhibitory peptide P{gamma}{sub 70-87} have been determined at 2.9 and 3.0 {angstrom}, respectively. These structures show the determinants and the mechanism of the PDE6 inhibition by P{gamma} and suggest the conformational change of P{gamma} on transducin activation. Two variable H- and M-loops of PDE5/6cd form a distinct interface that contributes to the P{gamma}-binding site. This allows the P{gamma} C-terminus to fit into the opening of the catalytic pocket, blocking cGMP access to the active site. Our analysis suggests that disruption of the H-M loop interface and P{gamma}-binding site is a molecular cause of retinal degeneration in atrd3 mice. Comparison of the two PDE5/6cd structures shows an overlap between the sildenafil and P{gamma}{sub 70-87}-binding sites, thereby providing critical insights into the side effects of PDE5 inhibitors on vision.

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

    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

  11. Systematic Review of Phosphodiesterase-5 Inhibitor Use in Right Ventricular Failure Following Left Ventricular Assist Device Implantation.

    Baker, William L; Radojevic, Joseph; Gluck, Jason A

    2016-02-01

    Our aim was to identify relevant literature supporting the use of phosphodiesterase-5 (PDE5) inhibitors in patients with persistent pulmonary hypertension with signs of postprocedural right ventricular (RV) dysfunction following left ventricular assist device (LVAD) implantation. We searched MEDLINE, SCOPUS, and Web of Science from inception through November 27, 2014 for citations evaluating patients with end-stage heart failure necessitating LVAD, continuous and pulsatile, who received a PDE5 inhibitor to prevent RV failure. Outcomes of interest included changes in mean pulmonary artery pressure, pulmonary vascular resistance, central venous pressure, cardiac index, and mean arterial pressure. Results are presented qualitatively. Four citations (n = 83 patients) were included. These included a single case report, two retrospective case series, and a prospective open-label study with a historical control. All four studies utilized the PDE5 inhibitor sildenafil with various doses for up to 3 months. Sildenafil routinely reduced mean pulmonary artery pressures as soon as 90 min after administration. Reductions in pulmonary vascular resistance were also seen shortly after the procedure and maintained through 12-15 weeks. While one study saw improvements in postoperative central venous pressures, another did not. Evidence supporting PDE5 inhibitor use to attenuate RV failure in patients requiring an LVAD is weak. PMID:26043796

  12. Phosphodiesterase 4D acts downstream of Neuropilin to control Hedgehog signal transduction and the growth of medulloblastoma.

    Ge, Xuecai; Milenkovic, Ljiljana; Suyama, Kaye; Hartl, Tom; Purzner, Teresa; Winans, Amy; Meyer, Tobias; Scott, Matthew P

    2015-01-01

    Alterations in Hedgehog (Hh) signaling lead to birth defects and cancers including medulloblastoma, the most common pediatric brain tumor. Although inhibitors targeting the membrane protein Smoothened suppress Hh signaling, acquired drug resistance and tumor relapse call for additional therapeutic targets. Here we show that phosphodiesterase 4D (PDE4D) acts downstream of Neuropilins to control Hh transduction and medulloblastoma growth. PDE4D interacts directly with Neuropilins, positive regulators of Hh pathway. The Neuropilin ligand Semaphorin3 enhances this interaction, promoting PDE4D translocation to the plasma membrane and cAMP degradation. The consequent inhibition of protein kinase A (PKA) enhances Hh transduction. In the developing cerebellum, genetic removal of Neuropilins reduces Hh signaling activity and suppresses proliferation of granule neuron precursors. In mouse medulloblastoma allografts, PDE4D inhibitors suppress Hh transduction and inhibit tumor growth. Our findings reveal a new regulatory mechanism of Hh transduction, and highlight PDE4D as a promising target to treat Hh-related tumors. PMID:26371509

  13. Sphingomyelin phosphodiesterase-1 (SMPD1 coding variants do not contribute to low levels of high-density lipoprotein cholesterol

    Genest Jacques

    2007-12-01

    Full Text Available Abstract Background Niemann-Pick disease type A and B is caused by a deficiency of acid sphingomyelinase due to mutations in the sphingomyelin phosphodiesterase-1 (SMPD1 gene. In Niemann-Pick patients, SMPD1 gene defects are reported to be associated with a severe reduction in plasma high-density lipoprotein (HDL cholesterol. Methods Two common coding polymorphisms in the SMPD1 gene, the G1522A (G508R and a hexanucleotide repeat sequence within the signal peptide region, were investigated in 118 unrelated subjects of French Canadian descent with low plasma levels of HDL-cholesterol (th percentile for age and gender-matched subjects. Control subjects (n = 230 had an HDL-cholesterol level > the 25th percentile. Results For G1522A the frequency of the G and A alleles were 75.2% and 24.8% respectively in controls, compared to 78.6% and 21.4% in subjects with low HDL-cholesterol (p = 0.317. The frequency of 6 and 7 hexanucleotide repeats was 46.2% and 46.6% respectively in controls, compared to 45.6% and 49.1% in subjects with low HDL-cholesterol (p = 0.619. Ten different haplotypes were observed in cases and controls. Overall haplotype frequencies in cases and controls were not significantly different. Conclusion These results suggest that the two common coding variants at the SMPD1 gene locus are not associated with low HDL-cholesterol levels in the French Canadian population.

  14. RACK1 and β-arrestin2 attenuate dimerization of PDE4 cAMP phosphodiesterase PDE4D5.

    Bolger, Graeme B

    2016-07-01

    PDE4 family cAMP-selective cyclic nucleotide phosphodiesterases are important in the regulation of cAMP abundance in numerous systems, and thereby play an important role in the regulation of PKA and EPAC activity and the phosphorylation of CREB. We have used the yeast 2-hybrid system to demonstrate recently that long PDE4 isoforms form homodimers, consistent with data obtained recently by structural studies. The long PDE4 isoform PDE4D5 interacts selectively with β-arrestin2, implicated in the regulation of G-protein-coupled receptors and other cell signaling components, and also with the β-propeller protein RACK1. In the present study, we use 2-hybrid approaches to demonstrate that RACK1 and β-arrestin2 inhibit the dimerization of PDE4D5. We also show that serine-to-alanine mutations at PKA and ERK1/2 phosphorylation sites on PDE4D5 detectably ablate dimerization. Conversely, phospho-mimic serine-to-aspartate mutations at the MK2 and oxidative stress kinase sites ablate dimerization. Analysis of PDE4D5 that is locked into the dimeric configuration by the formation of a trans disulfide bond between Ser261 and Ser602 shows that RACK1 interacts strongly with both the monomeric and dimeric forms, but that β-arrestin2 interacts exclusively with the monomeric form. This is consistent with the concept that β-arrestin2 can preferentially recruit the monomeric, or "open," form of PDE4D5 to β2-adrenergic receptors, where it can regulate cAMP signaling. PMID:26257302

  15. Characterization of sensory neuron subpopulations selectively expressing green fluorescent protein in phosphodiesterase 1C BAC transgenic mice

    Anderson Rebecca L

    2006-05-01

    Full Text Available Abstract Background The complex neuronal circuitry of the dorsal horn of the spinal cord is as yet poorly understood. However, defining the circuits underlying the transmission of information from primary afferents to higher levels is critical to our understanding of sensory processing. In this study, we have examined phosphodiesterase 1C (Pde1c BAC transgenic mice in which a green fluorescent protein (GFP reporter gene reflects Pde1c expression in sensory neuron subpopulations in the dorsal root ganglia and spinal cord. Results Using double labeling immunofluorescence, we demonstrate GFP expression in specific subpopulations of primary sensory neurons and a distinct neuronal expression pattern within the spinal cord dorsal horn. In the dorsal root ganglia, their distribution is restricted to those subpopulations of primary sensory neurons that give rise to unmyelinated C fibers (neurofilament 200 negative. A small proportion of both non-peptidergic (IB4-binding and peptidergic (CGRP immunoreactive subclasses expressed GFP. However, GFP expression was more common in the non-peptidergic than the peptidergic subclass. GFP was also expressed in a subpopulation of the primary sensory neurons immunoreactive for the vanilloid receptor TRPV1 and the ATP-gated ion channel P2X3. In the spinal cord dorsal horn, GFP positive neurons were largely restricted to lamina I and to a lesser extent lamina II, but surprisingly did not coexpress markers for key neuronal populations present in the superficial dorsal horn. Conclusion The expression of GFP in subclasses of nociceptors and also in dorsal horn regions densely innervated by nociceptors suggests that Pde1c marks a unique subpopulation of nociceptive sensory neurons.

  16. Determination of phosphodiesterase type V inhibitors in wastewater by direct injection followed by liquid chromatography coupled to tandem mass spectrometry.

    Causanilles, Ana; Emke, Erik; de Voogt, Pim

    2016-09-15

    A simple, fast and reliable analytical method for the determination of phosphodiesterase type V inhibitors in wastewater was developed and validated. The method was based on direct injection followed by liquid chromatography coupled to tandem mass spectrometry with triple quadrupole as mass analyzer. Transformation products and analogues were included in the target list besides the three active pharmaceutical ingredients (sildenafil, vardenafil and tadalafil). The method performance was thoroughly investigated, including the analyte stability in wastewater and matrix effect. All target compounds presented linear fits between their LOD and 500ng/L. The quantification limits ranged from 1.6 to 30ng/L for all compounds except for n-octylnortadalafil (LOQ: 100ng/L); precision calculated as intraday repeatability was lower than 30%; accuracy calculated as procedural recovery ranged successfully between 85 and 105% in all cases. The method was applied to samples collected during three week-long monitoring campaigns performed in 2013, 2014 and 2015 in three Dutch cities. Only sildenafil and its two metabolites, desmethyl- and desethylsildenafil, were present with normalized loads ranging from LOQ to 8.3, 11.8 and 21.6mg/day/1000 inh, respectively. Two additional week-long sets of samples were collected in Amsterdam at the time that a festival event took place, bringing around 350,000 visitors to the city. The difference in drug usage patterns was statistically studied: "weekday" versus "weekend", "normal" versus "atypical" week; and results discussed. The metabolite to parent drug concentration ratio evolution during consecutive years was discussed, leading to several possible explanations that should be further investigated. Finally, wastewater-based epidemiology approach was applied to back-calculate sildenafil consumption. PMID:27161135

  17. Characterization of particulate cyclic nucleotide phosphodiesterases from bovine brain: Purification of a distinct cGMP-stimulated isoenzyme

    In the absence of detergent, ∼80-85% of the total cGMP-stimulated phosphodiesterase (PDE) activity in bovine brain was associated with washed particulate fractions; ∼85-90% of the calmodulin-sensitive PDE was soluble. Particulate cGMP-stimulated PDE was higher in cerebral cortical gray matter than in other regions. Homogenization of the brain particulate fraction in 1% Lubrol increased cGMP-stimulated activity ∼100% and calmodulin-stimulated ∼400-500%. Although 1% Lubrol readily solubilized these PDE activities, ∼75% of the cAMP PDE activity (0.5 μM [3H]cAMP) that was not affected by cGMP was not solubilized. This cAMP PDE activity was very sensitive to inhibition by Rolipram but not cilostamide. Thus, three different PDE types, i.e., cGMP stimulated, calmodulin sensitive, and Rolipram inhibited, are associated in different ways with crude bovine brain particulate fractions. The brain enzyme exhibited a slightly greater subunit Mr than did soluble forms from calf liver or bovine brain, as evidenced by protein staining or immunoblotting after polyacrylamide gel electrophoresis under denaturing conditions. Incubation of brain particulate and liver soluble cGMP-stimulated PDEs with V8 protease produced several peptides of similar size, as well as at least two distinct fragments of ∼27 kDa from the brain and ∼23 kDa from the liver enzyme. After photolabeling in the presence of [32P]cGMP and digestion with V8 protease, [32P]cGMP in each PDE was predominantly recovered with a peptide of ∼14 kDa. All of these observations are consistent with the existence of at least two discrete forms (isoenzymes) of cGMP-stimulated PDE

  18. The role of phosphodiesterase type-5 inhibitors in treatment of lower urinary tract symptoms associated with benign prostatic hyperplasia.

    Umul, Mehmet; Serel, Tekin Ahmet

    2013-12-01

    Phosphodiesterase type-5 (PDE-5) inhibitors are approved as the first line of therapy for the treatment of erectile dysfunction. However, different studies have been performed to study the use of these agents in other areas of urology. There are many studies related to the use of PDE-5 inhibitors as a monotherapy or combination therapy with alpha-blockers for lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH). It has been shown that contractions induced by various agents or electrical field stimulation in organ bath models of prostatic tissue can be reversed by PDE-5 inhibitors. Age, body mass index and the severity of LUTS are important factors for the selection of patients suitable for this treatment. It has also been reported that the use of PDE-5 inhibitors can relieve the chronic pelvic ischemia and endothelial dysfunction associated with metabolic syndrome. Most of the side effects observed with PDE-5 inhibitors are minimal and tolerable. The use of PDE-5 inhibitors is absolutely contraindicated in patients taking nitrate preparations. A significant interaction has not been observed even when a patient is taking several antihypertensive agents concurrently. Co-administration of alpha-blockers and PDE-5 inhibitors may result in orthostatic hypotension; therefore, patients should be stable on α-blocker therapy before the initiation of the combination therapy, and the initial PDE-5 inhibitor dose should be the lowest possible. In this review, our aim was to evaluate the role of PDE-5 inhibitors in the treatment of LUTS associated with BPH by analyzing the current literature. PMID:26328121

  19. Synthetic phosphodiesterase-5-inhibitors use/abuse and interest of hair testing: reporting of a rape case.

    Duez, Mathieu; Etter, Matthieu; Klinger, Nadine; Cirimele, Vincent

    2014-06-01

    If classic phosphodiesterase-5 (PDE-5) inhibitors are well known, new synthetic PDE-5 analogues are of more recent introduction. Some of them have already been tested in dietary supplements. We describe here a rape case following the consumption of pills bought on the Internet and containing new synthetic PDE-5 inhibitors. The assailant declared that he lost control after ingesting these pills for the first time. Analyses of conventional matrices (blood, urine) don't allow us to highlight the intake of any substances in relation to this offence due to late sampling (5 days after the offence). Therefore, we have developed an analytical approach to test for PDE-5 inhibitors in hair including the two new synthetic PDE-5 inhibitors analogues - thiosildenafil and hydroxythiohomosildenafil - previously identified in the pills. This new method was validated and applied to the hair samples of the victim and the suspect. Analyses were conducted using a liquid/liquid extraction followed by liquid chromatography coupled with a mass spectrometer in multiple reaction monitoring mode detection. The 2-centimetre proximal hair section of the suspect revealed the presence of thiosildenafil (48 pg/mg), hydroxythiohomosildenafil (24 pg/mg), and sildenafil (7.5 pg/mg). To our knowledge, it is the first time that these two new synthetic PDE-5 inhibitors were detected in biological samples and especially in hair. Complementary investigations showed that a single pill taken by a volunteer provided similar levels in thiosildenafil (35 pg/mg), hydroxythiohomosildenafil (17 pg/mg), and sildenafil (8 pg/mg) to those found in the previous case described here. PMID:24817044

  20. The Phosphodiesterase 10A Selective Inhibitor TAK-063 Improves Cognitive Functions Associated with Schizophrenia in Rodent Models.

    Shiraishi, Eri; Suzuki, Kazunori; Harada, Akina; Suzuki, Noriko; Kimura, Haruhide

    2016-03-01

    Cognitive deficits in various domains, including recognition memory, attention, impulsivity, working memory, and executive function, substantially affect functional outcomes in patients with schizophrenia. TAK-063 [1-[2-fluoro-4-(1H-pyrazol-1-yl)phenyl]-5-methoxy-3-(1-phenyl-1H-pyrazol-5-yl)pyridazin-4(1H)-one] is a potent and selective phosphodiesterase 10A inhibitor that produces antipsychotic-like effects in rodent models of schizophrenia. We evaluated the effects of TAK-063 on multiple cognitive functions associated with schizophrenia using naïve and drug-perturbed rodents. TAK-063 at 0.1 and 0.3 mg/kg p.o. improved time-dependent memory decay in object recognition in naïve rats. TAK-063 at 0.1 and 0.3 mg/kg p.o. increased accuracy rate, and TAK-063 at 0.3 mg/kg p.o. reduced impulsivity in a five-choice serial reaction time task in naïve rats. N-methyl-d-aspartate receptor antagonists, such as phencyclidine and MK-801 [(5R,10S)-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine], were used to induce working memory deficits relevant to schizophrenia in animals. TAK-063 at 0.3 mg/kg p.o. attenuated both phencyclidine-induced working memory deficits in a Y-maze test in mice and MK-801-induced working memory deficits in an eight-arm radial maze task in rats. An attentional set-shifting task using subchronic phencyclidine-treated rats was used to assess the executive function. TAK-063 at 0.3 mg/kg p.o. reversed cognitive deficits in extradimensional shifts. These findings suggest that TAK-063 has a potential to ameliorate deficits in multiple cognitive domains impaired in schizophrenia. PMID:26675680

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

    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

    2016-04-01

    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. PMID:26980711

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

    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.

  3. Mechanisms of cyclic nucleotide phosphodiesterases in modulating T cell responses in murine graft-versus-host disease.

    Weber, Michael; Lupp, Corinna; Stein, Pamela; Kreft, Andreas; Bopp, Tobias; Wehler, Thomas C; Schmitt, Edgar; Schild, Hansjörg; Radsak, Markus P

    2013-01-01

    Graft-versus-host disease (GvHD) is a key contributor to the morbidity and mortality after allogeneic hematopoetic stem cell transplantation (HSCT). Regulatory Foxp3(+) CD4(+) T cells (Treg) suppress conventional T cell activation and can control GvHD. In our previous work, we demonstrate that a basic mechanism of Treg mediated suppression occurs by the transfer of cyclic adenosine monophosphate (cAMP) to responder cells. Whether this mechanism is relevant for Treg mediated suppression of GvHD is currently unknown. To address this question, bone marrow and T cells from C57BL/6 mice were transferred into lethally irradiated BALB/c recipients, and the course of GvHD and survival were monitored. Transplanted recipients developed severe GvHD that was strongly ameliorated by the transfer of donor Treg cells. Towards the underlying mechanisms, in vitro studies revealed that Treg communicated with DCs via gap junctions, resulting in functional inactivation of DC by a metabolic pathway involving cAMP that is modulated by the phosphodiesterase (PDE) 4 inhibitor rolipram. PDE2 or PDE3 inhibitors as well as rolipram suppressed allogeneic T cell activation, indirectly by enhancing Treg mediated suppression of DC activation and directly by inhibiting responder T cell proliferation. In line with this, we observed a cooperative suppression of GvHD upon Treg transfer and additional rolipram treatment. In conclusion, we propose that an important pathway of Treg mediated control of GvHD is based on a cAMP dependent mechanism. These data provide the basis for future concepts to manipulate allogeneic T cell responses to prevent GvHD. PMID:23483980

  4. Therapeutic synergy and complementarity for ischemia/reperfusion injury: β1-adrenergic blockade and phosphodiesterase-3 inhibition.

    Huang, Ming-He; Poh, Kian-Keong; Tan, Huay-Cheem; Welt, Frederick G P; Lui, Charles Y

    2016-07-01

    The β1-blocker when administered before reperfusion activates myocyte prosurvival signaling via β2-adrenergic receptor (β2-AR) and protein kinase A (PKA)-dependent mechanism during ischemia/reperfusion (I/R). The heart is endowed with powerful self-protective ability executed by endogenous β2-adrenopeptide receptor activation. I/R triggers cardiac epinephrine and neuropeptide calcitonin gene-related peptide (CGRP) release. Cardiac β1- and β2-AR stimulation mediates pro- and anti-apoptotic cell signaling, respectively. Removal of myocardial β1-AR-derived proapoptotic force with β1-AR blockade unmasks the dominance of β2-AR mediated prosurvival cell signaling through the well-defined PKA-Akt dependent mechanism. This review focuses on recent clinical and experimental findings including intrinsic cardiac β2-adrenopeptide neuroparacrine signaling mechanisms involved in I/R injury protection. While β2-adrenopeptide-mediated cardioprotection is important, age-related β2-adrenopeptide receptor decoupling can result in their ineffectiveness in response to the receptor-specific therapies. Accordingly, direct activation of receptor-coupled upstream PKA-dependent signaling may serve as a therapeutic alternative to achieve cardioprotection bypassing adrenopeptidergic receptor decoupling accompanied with aging. Phosphodiesterase-3 (PDE3) inhibitor reduces infarct-size via cAMP-dependent PKA signaling. Non-β1-AR-mediated PKA activation activates multiple prosurvival signaling pathways eventually leading to Akt activation. Combination therapy with β1-blocker esmolol and PDE3 inhibitor milrinone additively reduced infarct-size in preclinical studies. Concurrent β1-AR blockade and PDE3 inhibition provides complementary synergy with promising therapeutic potential in patients with acute myocardial infarction and beyond. PMID:27085132

  5. Studying mechanisms of cAMP and cyclic nucleotide phosphodiesterase signaling in Leydig cell function with phosphoproteomics.

    Golkowski, Martin; Shimizu-Albergine, Masami; Suh, Hyong Won; Beavo, Joseph A; Ong, Shao-En

    2016-07-01

    Many cellular processes are modulated by cyclic AMP and nucleotide phosphodiesterases (PDEs) regulate this second messenger by catalyzing its breakdown. The major unique function of testicular Leydig cells is to produce testosterone in response to luteinizing hormone (LH). Treatment of Leydig cells with PDE inhibitors increases cAMP levels and the activity of its downstream effector, cAMP-dependent protein kinase (PKA), leading to a series of kinase-dependent signaling and transcription events that ultimately increase testosterone release. We have recently shown that PDE4B and PDE4C as well as PDE8A and PDE8B are expressed in rodent Leydig cells and that combined inhibition of PDE4 and PDE8 leads to dramatically increased steroid biosynthesis. Here we investigated the effect of PDE4 and PDE8 inhibition on the molecular mechanisms of cAMP actions in a mouse MA10 Leydig cell line model with SILAC mass spectrometry-based phosphoproteomics. We treated MA10 cells either with PDE4 family specific inhibitor (Rolipram) and PDE8 family specific inhibitor (PF-04957325) alone or in combination and quantified the resulting phosphorylation changes at five different time points between 0 and 180min. We identified 28,336 phosphosites from 4837 proteins and observed significant regulation of 749 sites in response to PDE4 and PDE8 inhibitor treatment. Of these, 132 phosphosites were consensus PKA sites. Our data strongly suggest that PDE4 and PDE8 inhibitors synergistically regulate phosphorylation of proteins required for many different cellular processes, including cell cycle progression, lipid and glucose metabolism, transcription, endocytosis and vesicle transport. Our data suggests that cAMP, PDE4 and PDE8 coordinate steroidogenesis by acting on not one rate-limiting step but rather multiple pathways. Moreover, the pools of cAMP controlled by these PDEs also coordinate many other metabolic processes that may be regulated to assure timely and sufficient testosterone secretion

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

    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. PMID:26432981

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

    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.

  8. Protective effects of phosphodiesterase inhibitors on lung function and remodeling in a murine model of chronic asthma

    H.S. Campos

    2006-02-01

    Full Text Available The aim of the present study was to compare the efficacy of a novel phosphodiesterase 4 and 5 inhibitor, LASSBio596, with that of dexamethasone in a murine model of chronic asthma. Lung mechanics (airway resistance, viscoelastic pressure, and static elastance, histology, and airway and lung parenchyma remodeling (quantitative analysis of collagen and elastic fiber were analyzed. Thirty-three BALB/c mice were randomly assigned to four groups. In the asthma group (N = 9, mice were immunized with 10 µg ovalbumin (OVA, ip on 7 alternate days, and after day 40 they were challenged with three intratracheal instillations of 20 µg OVA at 3-day intervals. Control mice (N = 8 received saline under the same protocol. In the dexamethasone (N = 8 and LASSBio596 (N = 8 groups, the animals of the asthma group were treated with 1 mg/kg dexamethasone disodium phosphate (0.1 mL, ip or 10 mg/kg LASSBio596 dissolved in dimethyl sulfoxide (0.2 mL, ip 24 h before the first intratracheal instillation of OVA, for 8 days. Airway resistance, viscoelastic pressure and static elastance increased significantly in the asthma group (77, 56, and 76%, respectively compared to the control group. The asthma group presented more intense alveolar collapse, bronchoconstriction, and eosinophil and neutrophil infiltration than the control group. Both LASSBio596 and dexamethasone inhibited the changes in lung mechanics, tissue cellularity, bronchoconstriction, as well as airway and lung parenchyma remodeling. In conclusion, LASSBio596 at a dose of 10 mg/kg effectively prevented lung mechanical and morphometrical changes and had the potential to block fibroproliferation in a BALB/c mouse model of asthma.

  9. Analysis of the Active-Site Mechanism of Tyrosyl-DNA Phosphodiesterase I: A Member of the Phospholipase D Superfamily

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

    2012-03-15

    Tyrosyl-DNA phosphodiesterase I (Tdp1) is a member of the phospholipase D superfamily that hydrolyzes 3'-phospho-DNA adducts via two conserved catalytic histidines - one acting as the lead nucleophile and the second acting as a general acid/base. Substitution of the second histidine specifically to arginine contributes to the neurodegenerative disease spinocerebellar ataxia with axonal neuropathy (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 the access of 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 substitutions with Asn, Gln, Leu, Ala, Ser, and Thr all result in severely compromised enzymes and DNA topoisomerase I-camptothecin dependent lethality. Surprisingly, His432Asn did not show a stable covalent Tdp1-DNA intermediate that suggests another catalytic defect. Theoretical calculations revealed that the defect resides in the nucleophilic histidine and that the pK{sub a} of this histidine is crucially dependent on the second histidine and on the incoming phosphate of the substrate. This represents a unique example of substrate-activated catalysis that applies to the entire phospholipase D superfamily.

  10. Phosphodiesterase-4 modulation as a potential therapeutic for cognitive loss in pathological and non-pathological aging: possibilities and pitfalls.

    Hansen, Rolf T; Zhang, Han-Ting

    2015-01-01

    Phosphodiesterases (PDEs) are a super family of 11 enzyme families responsible for the hydrolysis of the intracellular secondary messengers cyclic AMP (cAMP) and cyclic GMP (cGMP). PDE4, in particular, is highly expressed in brain regions involved with regulation of memory, anxiety, and depression, including the hippocampus, amygdala, and nucleus accumbens. Senescence has been shown to result in extreme dysregulation of the cAMP pathway in various brain regions. Thus, as a critical controller of intracellular cAMP levels, PDE4 may be a potential target for the treatment of senescence-related cognitive disorders, which could be pathological and/or non-pathological in origin. While there is great potential in the development of novel PDE4 inhibitors for treatment of senescent-cognition impairment, there are also currently many pitfalls that need to be overcome. PDE4 has four subfamilies (PDE4A, B, C, and D) that are differentially expressed throughout the brain and body, as well as at least 25 splice variants derived from alternative splicing and multiple promoter sites. PDE4 subtypes have been shown to have differential effects on behavior, and cAMP itself has also been shown to play a contrasting role in behavior in different brain regions. This review will focus on what is currently understood about PDE4 in aging, the potential for PDE4 modulation as a cognitive therapy, and current pitfalls and limitations that need to be overcome in the PDE4 field. Overall, furthering our understanding of this incredibly complex pathway may one day assist with the development of novel therapeutics for both pathological and non-pathological cognitive disorders associated with senescence. PMID:25159075

  11. Protective effects of phosphodiesterase inhibitors on lung function and remodeling in a murine model of chronic asthma

    Campos H.S.

    2006-01-01

    Full Text Available The aim of the present study was to compare the efficacy of a novel phosphodiesterase 4 and 5 inhibitor, LASSBio596, with that of dexamethasone in a murine model of chronic asthma. Lung mechanics (airway resistance, viscoelastic pressure, and static elastance, histology, and airway and lung parenchyma remodeling (quantitative analysis of collagen and elastic fiber were analyzed. Thirty-three BALB/c mice were randomly assigned to four groups. In the asthma group (N = 9, mice were immunized with 10 µg ovalbumin (OVA, ip on 7 alternate days, and after day 40 they were challenged with three intratracheal instillations of 20 µg OVA at 3-day intervals. Control mice (N = 8 received saline under the same protocol. In the dexamethasone (N = 8 and LASSBio596 (N = 8 groups, the animals of the asthma group were treated with 1 mg/kg dexamethasone disodium phosphate (0.1 mL, ip or 10 mg/kg LASSBio596 dissolved in dimethyl sulfoxide (0.2 mL, ip 24 h before the first intratracheal instillation of OVA, for 8 days. Airway resistance, viscoelastic pressure and static elastance increased significantly in the asthma group (77, 56, and 76%, respectively compared to the control group. The asthma group presented more intense alveolar collapse, bronchoconstriction, and eosinophil and neutrophil infiltration than the control group. Both LASSBio596 and dexamethasone inhibited the changes in lung mechanics, tissue cellularity, bronchoconstriction, as well as airway and lung parenchyma remodeling. In conclusion, LASSBio596 at a dose of 10 mg/kg effectively prevented lung mechanical and morphometrical changes and had the potential to block fibroproliferation in a BALB/c mouse model of asthma.

  12. INVESTIGATION OF SEIZURE ACTIVITY AFTER CYCLIC NUCLEOTIDE PHOSPHODIESTERASE INHIBITION WITH SECOND MESSENGER AND CALCIUM ION CHANNEL INHIBITION IN MICE

    J Nandhakumar

    2012-03-01

    Full Text Available The role of PDE-4 inhibitor etazolate, was evaluated in the presence of PDE-7 inhibitor, BRL-50481, in animal models of epilepsy. Seizures were induced in the animals by subjecting them to injection of chemical convulsants, Pilocarpine, Kainic acid (KA and maximal electroshock (MES. The combination of etazolate and BRL50481 treated mice showed a significant (P<0.001 quick onset of action, jerky movements and convulsion when compared to gabapentin. The combination of etazolate and sGC inhibitor, methylene blue (MB treated mice showed a significant (P<0.001 delay in onset of action, jerky movements and convulsion when compare to gabapentin as well as against the combination of etazolate with BRL 50481.The present study mainly highlights the individual effects of etazolate and combination with BRL-50481 potentiates (P<0.001 the onset of seizure activity against all models of convulsion. The study mainly comprises the onset of seizures, mortality/recovery, percentage of prevention of seizures (anticonvulsant and total duration of convulsive time. The total convulsive time was prolonged significantly (P<0.05 and P<0.01 in combination of methylene blue with etazolate treated (28.59% and 35.15 % groups, compared to DMSO received group (100% in the MES model. In the same way, the combination of calcium channel modulator (CCM and calcium channel blocker (CCB amiodarone and nifedipine respectively, with etazolate showed a significant (P<0.001 delay in onset of seizures, compared to DMSO and etazolate treated groups in all models of epilepsy. This confirms that both CCM and CCB possess anticonvulsant activity. Finally, the study reveals that identification of new cAMP mediated phosphodiesterases family members offers a potential new therapy for epilepsy management in future.

  13. Role of phosphodiesterase 4 expression in the Epac1 signaling-dependent skeletal muscle hypertrophic action of clenbuterol.

    Ohnuki, Yoshiki; Umeki, Daisuke; Mototani, Yasumasa; Shiozawa, Kouichi; Nariyama, Megumi; Ito, Aiko; Kawamura, Naoya; Yagisawa, Yuka; Jin, Huiling; Cai, Wenqian; Suita, Kenji; Saeki, Yasutake; Fujita, Takayuki; Ishikawa, Yoshihiro; Okumura, Satoshi

    2016-05-01

    Clenbuterol (CB), a selective β2-adrenergic receptor (AR) agonist, induces muscle hypertrophy and counteracts muscle atrophy. However, it is paradoxically less effective in slow-twitch muscle than in fast-twitch muscle, though slow-twitch muscle has a greater density of β-AR We recently demonstrated that Epac1 (exchange protein activated by cyclic AMP [cAMP]1) plays a pivotal role in β2-AR-mediated masseter muscle hypertrophy through activation of the Akt and calmodulin kinase II (CaMKII)/histone deacetylase 4 (HDAC4) signaling pathways. Here, we investigated the role of Epac1 in the differential hypertrophic effect of CB using tibialis anterior muscle (TA; typical fast-twitch muscle) and soleus muscle (SOL; typical slow-twitch muscle) of wild-type (WT) and Epac1-null mice (Epac1KO). The TA mass to tibial length (TL) ratio was similar in WT and Epac1KO at baseline and was significantly increased after CB infusion in WT, but not in Epac1KO The SOL mass to TL ratio was also similar in WT and Epac1KO at baseline, but CB-induced hypertrophy was suppressed in both mice. In order to understand the mechanism involved, we measured the protein expression levels of β-AR signaling-related molecules, and found that phosphodiesterase 4 (PDE4) expression was 12-fold greater in SOL than in TA These results are consistent with the idea that increased PDE4-mediated cAMP hydrolysis occurs in SOL compared to TA, resulting in a reduced cAMP concentration that is insufficient to activate Epac1 and its downstream Akt and CaMKII/HDAC4 hypertrophic signaling pathways in SOL of WT This scenario can account for the differential effects of CB on fast- and slow-twitch muscles. PMID:27207782

  14. Sex-dependent association of phosphodiesterase 4D gene polymorphisms with ischemic stroke in Henan Han population

    HE Ying; QI Hua; SONG Guo-ying; ZHENG Hong; XU Yu-ming; BAI Jun-yu; SONG Bo; TAN Song; CHANG Yin-shu; LI Tao; SHI Cong-cong; ZHANG Hua; FENG Qing-chuan

    2012-01-01

    Background Recent evidence has implicated the gene for phosphodiesterase 4D (PDE4D) as susceptibility gene for ischemic stroke (IS) in lcelandic population.However,there are few reports on the associations between PDE4D gene polymorphisms and IS in Chinese individuals.The present study aimed to investigate the possible association of genetic polymorphisms in PDE4D gene with IS in Henan Han population.Methods A total of 400 patients with IS and 400 matched controls were examined using a case-control design.Two single nucleotide polymorphism (SNPs) (rs918592 and rs2910829) in PDE4D gene were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.Odds ratios (OR) and 95% confidence intervals (95% Cl) were calculated to test the association between the genetic factors and IS.Genetic parameter and association studies were carried out with SPSS 16.0.Results Among the two SNPs tested,the rs918592 was significantly associated with IS (OR:1.351,95% Cl:1.110-1.645),especially in male patients (OR:1.427,95% Cl:1.105-1.844).Haplotype analysis showed that A-T was associated with an increased risk of the IS (OR:2.114,95% Cl:2.005-2.230) while G-T was associated with decreased risk of IS (OR:0.419,95% Cl:0.302-0.583).Protecting effect of haplotype G-T was also significant in males (OR:0.264,95% Cl:0.162-0.431).Conclusions The present study demonstrated a strong association of rs918592 with IS.Haplotype A-T increased the risk of IS while haplotype G-T had a protective effect in Henan Hen population.The association was sex-dependent with male patients showing stronger effect.

  15. NF-κB Upregulates Type 5 Phosphodiesterase in N9 Microglial Cells: Inhibition by Sildenafil and Yonkenafil.

    Zhao, Siqi; Yang, Jingyu; Wang, Lixin; Peng, Shengyi; Yin, Jie; Jia, Lina; Yang, Xiaowei; Yuan, Zengqiang; Wu, Chunfu

    2016-05-01

    Our previous studies showed that the phosphodiesterase-5 (PDE5) inhibitor sildenafil inhibited the microglial activation induced by lipopolysaccharide (LPS). However, whether yonkenafil, a novel PDE5 inhibitor, also inhibits microglial activation and the underlying mechanism of inhibition remain elusive. Here we found that yonkenafil significantly suppressed the production of NO, interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) and the protein expression of inducible NO synthase (iNOS) induced by LPS in microglial cells in a concentration-dependent manner. Knockdown of PDE5 inhibits NO and iNOS protein expression in LPS-stimulated N9 microglia. Moreover, we observed that the nuclear factor-κB (NF-κB) transcriptionally upregulated PDE5 expression, which was inhibited by sildenafil and yonkenafil in LPS-stimulated N9 microglia. Therefore, sildenafil and yonkenafil may exert their inhibitory effects on microglial activation by reducing the expression of PDE5. Furthermore, sildenafil and yonkenafil increased the cyclic guanosine monophosphate (cGMP) level in N9 microglia, and 8-Br-cGMP, an analogue of cGMP, downregulates extracellular signal-regulated kinases 1 and 2 (ERK1/2)/the NF-κB pathway, suggesting that sildenafil and yonkenafil inhibit microglial activation by decreasing PDE5 expression and increasing the cGMP level. Importantly, sildenafil and yonkenafil significantly alleviated the death of SH-SY5Y neuroblastoma cells and primary cortical neurons induced by the conditioned medium from activated microglia. Together, these findings position PDE5 as a potential therapy target for the treatment of neuroinflammation accompanied by microglial activation. PMID:26108184

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

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

    2004-01-01

    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 m...

  17. Phosphodiesterase type 5 inhibitors for treating erectile dysfunction and lower urinary tract symptoms secondary to benign prostatic hyperplasia: A comprehensive review

    Haddad, Albert; Jabbour, Michel; Bulbul, Muhammad

    2015-01-01

    Many men have coexistent erectile dysfunction (ED) and lower urinary tract symptoms secondary to benign prostatic hyperplasia (LUTS/BPH). Phosphodiesterase type 5 (PDE5) inhibitors are effective for treating both of these conditions independently. In this review we summarise the evidence supporting a link between ED and LUTS/BPH, and the results from key clinical studies related to the use of PDE5 inhibitors for treating both conditions. The results from these studies suggest that men who have both ED and LUTS/BPH, and are concerned about their sexual dysfunction, might benefit from single-agent, holistic treatment with a PDE5 inhibitor. PMID:26413339

  18. Targeted disruption of the heat shock protein 20–phosphodiesterase 4D (PDE4D interaction protects against pathological cardiac remodelling in a mouse model of hypertrophy

    Tamara P. Martin

    2014-01-01

    Full Text Available Phosphorylated heat shock protein 20 (HSP20 is cardioprotective. Using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs and a mouse model of pressure overload mediated hypertrophy, we show that peptide disruption of the HSP20–phosphodiesterase 4D (PDE4D complex results in attenuation of action potential prolongation and protection against adverse cardiac remodelling. The later was evidenced by improved contractility, decreased heart weight to body weight ratio, and reduced interstitial and perivascular fibrosis. This study demonstrates that disruption of the specific HSP20–PDE4D interaction leads to attenuation of pathological cardiac remodelling.

  19. A quantitative comparison of functional and anti-ischaemic effects of the phosphodiesterase-inhibitors, amrinone, milrinone and levosimendan in rabbit isolated hearts.

    Rump, A. F.; Acar, D.; Klaus, W.

    1994-01-01

    1. The functional and anti-ischaemic effects of the phosphodiesterase (PDE)-inhibitors, amrinone, milrinone and levosimendan, a new agent combining PDE-inhibitory with calcium-sensitizing properties, were investigated in rabbit isolated hearts (Langendorff, constant pressure: 70 cmH2O, Tyrode solution, Ca2+ 1.8 mmol l-1, 37 degrees C). Anti-ischaemic effects were studied in electrically-driven hearts (200 beats min-1). Acute regional ischaemia was induced by ligature of a branch of the circum...

  20. A positive feedback loop of phosphodiesterase 3 (PDE3) and inducible cAMP early repressor (ICER) leads to cardiomyocyte apoptosis

    Ding, Bo; Abe, Jun-ichi; Wei, Heng; Xu, Haodong; Che, Wenyi; Aizawa, Toru; Liu, Weimin; Molina, Carlos A.; Sadoshima, Junichi; Blaxall, Burns C.; Berk, Bradford C.; Yan, Chen

    2005-01-01

    cAMP plays crucial roles in cardiac remodeling and the progression of heart failure. Recently, we found that expression of cAMP hydrolyzing phosphodiesterase 3A (PDE3A) was significantly reduced in human failing hearts, accompanied by up-regulation of inducible cAMP early repressor (ICER) expression. Angiotensin II (Ang II) and the β-adrenergic receptor agonist isoproterenol (ISO) also induced persistent PDE3A down-regulation and concomitant ICER up-regulation in vitro, which is important in ...

  1. Cloning and expression of cDNA for a human low-K sub m , rolipram-sensitive cyclic AMP phosphodiesterase

    Livi, G.P.; McHale, M.J.; Sathe, G.M.; Taylor, D.P. (Dept. of Gene Expression Sciences, Smithkline Beecham Pharmaceuticals, King of Prussia, PA (US)); Kmetz, P.; Balcarek, J.M. (Dept. of Molecular Genetics, Smithkline Beecham Pharmaceuticals, King of Prussia, PA (US)); Cieslinski, L.B.; Torphy, T.J. (Dept. of Pharmacology, Smithkline Beecham Pharmaceuticals, King of Prussia, PA (US)); Davis, R.L. (Baylor Univ., Houston, TX (USA). Dept. of Cell Biology)

    1990-06-01

    The authors have isolated cDNA clones representing cyclic AMP (cAMP)-specific phosphodiesterases (PDEases) from a human monocyte cDNA library. One cDNA clone (hPDE-1) defines a large open reading frame of ca. 2.1 kilobases, predicting a 686-amino-acid, ca. 77-kilodalton protein which contains significant homology to both rat brain and {ital Drosophila} cAMP PDEases, especially within an internal conserved domain of ca. 270 residues. Amino acid sequence divergence exists at the NH{sub 2} terminus and also within a 40- to 100-residue domain near the COOH-terminal end. hPDE-1 hybridizes to a major 4.8-kilobase mRNA transcript from both human monocytes and placenta. The coding region of hPDE-1 was engineered for expression in COS-1 cells, resulting in the overproduction of cAMP PDEase activity. The hPDE-1 recombinant gene product was identified as a low-{ital K{sub m}} cAMP phosphodiesterase on the basis of several biochemical properties including selective inhibition by the antidepressant drug rolipram. Known inhibitors of other PDEases (cGMP-specific PDEase, cGMP-inhibited PDEase) had little or no effect on the hPDE-1 recombinant gene product.

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

    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.

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

    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)

  4. AB023. Penile rehabilitation with phosphodiesterase type 5 inhibitors in men after nerve-sparing radical prostatectomy

    Jiann, Bang-Ping

    2016-01-01

    Post-radical prostatectomy (RP) erectile dysfunction (ED) remains a challenge for the urologist. Despite the improvements in surgical technique, ED occurs between 20% and 90% in patients treated with bilateral nerve-sparing RP. Patient factors, cancer selection, type of surgery, surgical techniques, and surgeon factors represent the key significant contributors to erectile function recovery. The aim of a penile rehabilitation program is to preserve the functional smooth-muscle content of the corpus cavernosum during the neuropraxia period. Phosphodiesterase type 5 (PDE5) inhibitors are commonly used in rehabilitation programs. In animal models, such an approach could promote erectile function recovery, improve smooth muscle-to-collagen penile ration, reduce penile apoptotic index, preserve penile endothelial function and promote neuroprotection during nerve damage. Despite the strong basic science support from animal studies, discordant results have been reached in humans. The previous randomized trials comparing chronic versus on-demand PDE-5 inhibitors use after RP may be affected by improper patients’ selection in that only men at low risk of postoperative ED were included. These patients would recover erectile function regardless of the type of PDE5 inhibitor administration because of their excellent baseline profile. Prospective, randomized trials have shown a significant benefit of daily PDE5-I administration as compared with placebo in terms of postoperative EF recovery. Patients with intermediate risk of ED after surgery are the best candidates for daily treatment with PDE5 inhibitor after bilateral nerve-sparing RP. The maximal effect of penile rehabilitation may be found in those men with a certain (but not high) degree of systemic and erectile impairment preoperatively. In conclusion, penile rehabilitation could achieve faster and better natural erectile function after RP and should be started as early as possible. Chronic use of PDE5-I may confer the

  5. Validated UPLC-MS/MS assay for the determination of synthetic phosphodiesterase type-5 inhibitors in postmortem blood samples.

    Proença, Paula; Mustra, Carla; Marcos, Mariana; Franco, João Miguel; Corte-Real, Francisco; Vieira, Duarte Nuno

    2013-08-01

    The use of synthetic phosphodiesterase type 5 (PDE-5) inhibitors for the treatment of erectile dysfunction: sildenafil citrate (Viagra(®)), tadalafil (Cialis(®)) and vardenafil hydrochloride (Levitra(®)) has increased dramatically over the past 2 years. These substances are prescription drugs and must be used under medical supervision. However, they can easily be obtained over the internet from illegal sites, being a potential for a threat to public health. The development of an electrospray ionisation (ESI) ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) procedure for the simultaneous identification and quantification of three PDE5 inhibitors in blood samples was desired. Samples were prepared using Oasis(®) HLB solid-phase cartridges (3 cc, 60 mg) and chromatographic separation was achieved on an Acquity UPLC(®) HSS T3 (100 × 2.1 mm i.d., 1.8 μm particles) column with a gradient mobile phase of 0.1% formic acid and acetonitrile at a 0.5 mL/min flow rate. Quantification was achieved by multiple reaction monitoring (MRM) of two transitions per compound: m/z 475.1 > 58 e m/z 475.1 > 311.1 for sildenafil; m/z 389.9 > 267.9 e m/z 389.9 > 134.8 for tadalafil and m/z 489 > 71.9 e m/z 489 > 150.9 for vardenafil. Zolpidem-d6 (m/z 314.5 > 235.3) was used as the internal standard. Calibration curves were linear over the concentration range of 5-1000 ng/mL, with a coefficient of determination better than 0.997. The lower limits of detection and quantification for these substances were ≤ 3 ng/mL and ≤ 8 ng/mL, respectively. The method showed a satisfactory sensitivity, precision, accuracy, recovery and selectivity. A rapid, selective and sensitive UPLC-MS/MS method using solid-phase extraction was developed for the simultaneous determination and quantification of sildenafil, vardenafil and tadalafil in blood samples. PMID:23910856

  6. Phosphodiesterase-5 inhibitor tadalafil attenuates oxidative stress and protects against myocardial ischemia/reperfusion injury in type 2 diabetic mice.

    Koka, Saisudha; Das, Anindita; Salloum, Fadi N; Kukreja, Rakesh C

    2013-07-01

    Diabetic patients exhibit increased risk for the development of cardiovascular diseases primarily because of impaired nitric oxide (NO) bioavailability. The phosphodiesterase-5 (PDE-5) inhibitor sildenafil restores NO signaling and protects against ischemia/reperfusion (I/R) injury. In this study, we determined the effect of the long-acting PDE-5 inhibitor tadalafil on diabetes-associated complications and its role in attenuating oxidative stress after I/R injury in type 2 diabetic db/db mice. Adult male db/db mice (n=40/group) were randomized to receive dimethyl sulfoxide (10% DMSO, 0.2ml, ip) or tadalafil (1mg/kg in 10% DMSO, ip) for 28 days. After 28 days treatment, the hearts were isolated and subjected to 30min global ischemia followed by 60min reperfusion in the Langendorff mode. Infarct size was measured using computer morphometry of tetrazolium-stained sections. Cardiomyocytes were isolated from a subset of hearts and subjected to 40min simulated ischemia followed by 1h of reoxygenation (SI/RO). Dichlorodihydrofluorescein diacetate and JC-1 staining was used to measure reactive oxygen species (ROS) generation and mitochondrial membrane potential (Δψm), respectively. Another subset of hearts was used for the estimation of lipid peroxidation, glutathione, and the expression of myocardial pRac1, Rac1, gp91(phox), p47(phox), and p67(phox) by Western blot. Tadalafil treatment improved the metabolic status and reduced infarct size compared to the untreated db/db mice (21.2±1.8% vs 45.8±2.8%; p<0.01). The db/db mice showed enhanced oxidative stress in cardiomyocytes as indicated by a significant increase in ROS production. Cardiac NAD(P)H oxidase activity, lipid peroxidation, and oxidized glutathione were also increased in db/db mice compared to nondiabetic control animals. Tadalafil treatment in db/db mice suppressed oxidative stress, attenuated myocardial expression of pRac1 and gp91(phox), and also preserved the loss of Δψm in cardiomyocytes after SI

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

    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.

  8. Influence of erectile dysfunction course on its progress and efficacy of treatment with phosphodiesterase type 5 inhibitors

    LIU De-feng; JIANG Hui; HONG Kai; ZHAO Lian-ming; TANG Wen-hao; MA Lu-lin

    2010-01-01

    Background Erectile dysfunction (ED) is a common impairment among older men, and the prevalence rates increase sharply after age of 60 years. Most studies have focused on the prevalence rate or dangerouse factors. The aim of this study was to investigate the basic epidemiologic data about ED patients with different ED courses. The purpose of this researth was to understand the therapeutic effect of phosphodiesterase type 5 inhibitor (PDE5-1) and see how and why the ED course impact the progress of ED and the therapeutic effect of PDE5-1 treatment.Methods From June 2008 to June 2009, 4252 questionnaires (Quality of Erection Questionnaire, QEQ) were gathered from 46 centers by urology or andrology doctors all around China. Patients with ED (age > 20 years) filled in first half of the questionnaires when they came for the first time, and then completed the second half 4 weeks after PDE5-1 therapy.Results ED courses of most patients were less than 5 years (<5 years, 74.0%; 5-10 years 20.8%; >10 years, 5.2%). As ED course increasing, the incidence of the risk factors of ED, such as smoking, drinking, hypertension, diabetes, heart disease and hyperlipidemia also increase (P ≤0.01). PDE5-1 was effective in improving the quality of sexual activities (P ≤0.01). Administration of PDE5-1 improves satisfaction, enjoyment and frequency of sexual activities. The longer the ED course, the worse the therapeutic effect (<5 years, 96.1%; 5-10 years, 94.9%; >10 years, 89.0%) (P<0.01).Conclusions The ED course greatly affected the therapeutic effect of PDE5-1, the patients with ED should consult doctor at early stage of the disease. Admistration of PDE5-1 effectively improves the penile erection and the quality of sexual life of the patients hence should be considered as first-line medicine in the treatment of ED.

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

    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 Gi......-coupled GPCRs, which leads to increased or decreased cAMP levels, respectively. Here we describe a real-time Förster resonance energy transfer (FRET)-based cAMP high-throughput screening (HTS) assay for identification and characterization of Gs-coupled GPCR ligands and phosphodiesterase (PDE) inhibitors...... resulted in prolonged signaling and enabled detection of weak partial agonists and/or ligands with low potency, which is highly advantageous in large HTS settings and hit identification. In addition, the assay enabled detection of β2AR inverse agonists and PDE inhibitors. High signal-to-noise ratios were...

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

    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. PMID:25865678

  11. Extracellular phosphomono- and phosphodiesterase associated with and released by the roots of barley genotypes: a non-destructive method for the measurement of the extracellular enzymes of roots

    Asmar, Mohammad Farouq; Nielsen, Gunnar Gissel

    1997-01-01

    . The contribution of rhizoplane microorganisms to the root total activity of extracellular phosphomonoesterase was estimated to be 3%. Generally, the activity of the enzymes associated with the roots was 20-80 times higher than the activity of those released by the roots to the surrounding nutrient....... A method is described of growing plants individually under sterile and non-sterile conditions and assaying of the enzyme activities of intact roots and rhizoplane microorganisms. The results of the experiments presented in this paper indicate that all the genotypes showed significantly (P<0.......01) higher activity of extracellular phosphomonoesterase than that of phosphodiesterase both associated with and released by their roots. There were no significant differences (P<0.05) between the sterile and non-sterile root and its surrounding solutions in the activity of extracellular phosphomonoesterase...

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

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

    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 and...... headache induction. Ten healthy subjects were included in a double-blind, placebo-controlled crossover study where placebo or sildenafil 100 mg (highest therapeutic dose) were administered on two separate days. Blood velocity in the middle cerebral artery (Vmca) was recorded by transcranial Doppler, and...... repeatedly. Headache responses and tenderness of pericranial muscles were scored verbally. Sildenafil caused no significant changes in rCBFmca, Vmca, or in temporal or radial artery diameter, but heart rate increased and diastolic blood pressure decreased significantly compared to placebo. Despite the lack...

  13. Pregnancy induces a modulation of the cAMP phosphodiesterase 4-conformers ratio in human myometrium: consequences for the utero-relaxant effect of PDE4-selective inhibitors.

    Méhats, C; Tanguy, G; Paris, B; Robert, B; Pernin, N; Ferré, F; Leroy, M J

    2000-02-01

    The inhibitory impacts of RP 73401, a phosphodiesterase type 4 (PDE4) selective inhibitor of the second generation, versus rolipram, the prototypal PDE4 inhibitor, were evaluated and compared on cAMP phosphodiesterase (PDE) activity and contractility of the myometrium in nonpregnant and pregnant women. In enzymatic studies, RP 73401 and rolipram inhibited the cAMP PDE activity with significantly greater maximal efficiency in the myometrium of pregnant compared with nonpregnant women (75 versus 55%; P 0.01 to 100 microM (P <.01), whereas no difference was observed for the concentration range <0.01 microM. In contractility studies, RP 73401 was equally effective in relaxing myometrial strips from both nonpregnant and pregnant women (pD(2) = -8.8). Conversely, the ability of rolipram to inhibit contractions of the myometrium in pregnant women was significantly lower (pD(2) = -7.2) compared with that in nonpregnant women (pD(2) = -8.2; P <.01). Concomitantly, in the myometrium of pregnant women, a rise in immunoreactive PDE4B2 signal was detected, whereas the PDE4D3 signal was less intense. These results demonstrate that parallel to an accumulation of PDE4B2 isoform, a modification in the ratio of PDE4 conformers HPDE4 and LPDE4 (conformer that binds rolipram with high and low affinity, respectively) occurs in the myometrium of near-term pregnant women with an increase of LPDE4 functionally implicated in the contractile process. Such modifications provide a strong rationale to propose LPDE4 as potential pharmacologic targets for the design of new tocolytic treatments. PMID:10640323

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

    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.

  15. Novel high-throughput electrochemiluminescent assay for identification of human tyrosyl-DNA phosphodiesterase (Tdp1) inhibitors and characterization of furamidine (NSC 305831) as an inhibitor of Tdp1

    Antony, Smitha; Marchand, Christophe; Stephen, Andrew G.; Thibaut, Laurent; Agama, Keli K.; Fisher, Robert J.; Pommier, Yves

    2007-01-01

    By enzymatically hydrolyzing the terminal phosphodiester bond at the 3′-ends of DNA breaks, tyrosyl-DNA phosphodiesterase (Tdp1) repairs topoisomerase-DNA covalent complexes and processes the DNA ends for DNA repair. To identify novel Tdp1 inhibitors, we developed a high-throughput assay that uses electrochemiluminescent (ECL) substrates. Subsequent to screening of 1981 compounds from the ‘diversity set’ of the NCI-Developmental Therapeutics Program, here we report that furamidine inhibits Td...

  16. Effect of selective phosphodiesterase 4 inhibitor,rolipram, on cytokine and gelatinase B (MMP-9) release in the whole blood from adult patients with cystic fibrosis.

    JouneauSTEPHANE; BelleguicCHANTAL; EpinceALEXANDRAD; BrinchaultORAZIELLA; DesruesBENOIT; CamusCHRISTOPHE; MichelROUSSEY; LagenteVINCENT; CorinneAEMartin-CHOULY

    2004-01-01

    AIM: Inflammation plays a critical role in lung disease progression in cystic fibrosis being able to be associated with the development of tissue remodeling. These processes are mainly due to pro-inflammatory cytokines release and to an imbalance between proteases and antiproteases involving matrix metalloproteinases (MMP). Phosphodiesterase 4 (PDE4) inhibitors, by elevating intracellular cAMP, are known to be potent inhibitors of

  17. Vergleichende Untersuchungen zur Steigerung der Kontraktilität und der mechanischen Effizienz von Ferkel-Herzen nach kardioplegem Herzstillstand durch Kalziumsensitizer, Beta-Adrenozeptor-Agonisten und Phosphodiesterase-III-Hemmern im ex-situ ...

    Löhle, Thomas

    2006-01-01

    Vergleichende Untersuchungen zur Steigerung der Kontraktilität und der mechanischen Effizienz von Ferkel-Herzen nach kardioplegem Herzstillstand durch Kalziumsensitizer, Beta-Adrenozeptor-Agonisten und Phosphodiesterase-III-Hemmern im ex-situ Working Heart Modell Die vorliegende Studie untersucht den Einfluß des reinen (+) - Enantiomers des Kalziumsensitizers EMD 57033 auf die Myokardfunktion nach kardioplegem Herzstillstand. Die Wirkung wird im ex-situ Working Heart Modell mit der des Be...

  18. A Meta-Analysis of Long- Versus Short-Acting Phosphodiesterase 5 Inhibitors: Comparing Combination Use With α-Blockers and α-Blocker Monotherapy for Lower Urinary Tract Symptoms and Erectile Dysfunction

    Choi, Hoon; Kim, Hyun Jung; Bae, Jae Hyun; Kim, Jae Heon; Moon, Du Geon; Cheon, Jun; Yeo, Jeong-Kyun

    2015-01-01

    Purpose: Combination therapy with an α-1-adrenergic blocker and phosphodiesterase type 5 inhibitors (PDE5Is) has shown improvements in lower urinary tract symptoms (LUTS) with negligible side effects. Nonetheless, decisive advantages in symptom improvement were insufficient, and there were no clinical differences between long- or short-acting PDE5Is in combination with combination medication. Methods: To review the studies on α-1-adrenergic blocker monotherapy and combination therapy with lon...

  19. 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

    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.

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

    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

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

    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

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

    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

  3. Deazaflavin Inhibitors of Tyrosyl-DNA Phosphodiesterase 2 (TDP2) Specific for the Human Enzyme and Active against Cellular TDP2.

    Marchand, Christophe; Abdelmalak, Monica; Kankanala, Jayakanth; Huang, Shar-Yin; Kiselev, Evgeny; Fesen, Katherine; Kurahashi, Kayo; Sasanuma, Hiroyuki; Takeda, Shunichi; Aihara, Hideki; Wang, Zhengqiang; Pommier, Yves

    2016-07-15

    Tyrosyl-DNA phosphodiesterase 2 repairs irreversible topoisomerase II-mediated cleavage complexes generated by anticancer topoisomerase-targeted drugs and processes replication intermediates for picornaviruses (VPg unlinkase) and hepatitis B virus. There is currently no TDP2 inhibitor in clinical development. Here, we report a series of deazaflavin derivatives that selectively inhibit the human TDP2 enzyme in a competitive manner both with recombinant and native TDP2. We show that mouse, fish, and C. elegans TDP2 enzymes are highly resistant to the drugs and that key protein residues are responsible for drug resistance. Among them, human residues L313 and T296 confer high resistance when mutated to their mouse counterparts. Moreover, deazaflavin derivatives show potent synergy in combination with the topoisomerase II inhibitor etoposide in human prostate cancer DU145 cells and TDP2-dependent synergy in TK6 human lymphoblast and avian DT40 cells. Deazaflavin derivatives represent the first suitable platform for the development of potent and selective TDP2 inhibitors. PMID:27128689

  4. A novel phosphodiesterase-5 Inhibitor: Yonkenafil modulates neurogenesis, gliosis to improve cognitive function and ameliorates amyloid burden in an APP/PS1 transgenic mice model.

    Zhu, Lei; Yang, Jing-yu; Xue, Xue; Dong, Ying-xu; Liu, Yang; Miao, Feng-rong; Wang, Yong-feng; Xue, Hong; Wu, Chun-fu

    2015-09-01

    In Alzheimer's disease (AD), activated microglia invade and surround β-amyloid plaques, possibly contributing to the aggregation of amyloid β (Aβ), which affect the survival of neurons and lead to memory loss. Phosphodiesterase-5 (PDE-5) inhibitors have recently been shown a potential therapeutic effect on AD. In this study, the effects of yonkenafil (yonk), a novel PDE-5 inhibitor, on cognitive behaviors as well as the pathological features in transgenic AD mice were investigated. Seven-month-old APP/PS1 transgenic mice were treated with yonk (2, 6, or 18 mg/kg, intraperitoneal injection (i.p.)) or sildenafil (sild) (6 mg/kg, i.p.) daily for 3 months and then behavioral tests were performed. The results demonstrated that yonk improved nesting-building ability, ameliorated working memory deficits in the Y-maze tasks, and significantly improved learning and memory function in the Morris water maze (MWM) tasks. In addition, yonk reduced the area of Aβ plaques, and inhibited over-activation of microglia and astrocytes. Furthermore, yonk increased neurogenesis in the dentate granule brain region of APP/PS1 mice, indicated by increased BrdU(+)/NeuN(+) and BrdU(+)/DCX(+) cells compared to vehicle-treated transgenic mice. These results suggest that yonk could rescue cognitive deficits by ameliorated amyloid burden through regulating APP processing, inhibited the over-activation of microglia and astrocytes as well as restored neurogenesis. PMID:26200391

  5. Application of high-performance liquid chromatography with charged aerosol detection for universal quantitation of undeclared phosphodiesterase-5 inhibitors in herbal dietary supplements.

    Poplawska, Magdalena; Blazewicz, Agata; Bukowinska, Kinga; Fijalek, Zbigniew

    2013-10-01

    Incidents of detecting novel analogues of phosphodiesterase 5 (PDE-5) inhibitors in illicit dietary supplements for erectile dysfunction are constantly reported. However, little is known about their content in a single dose, mainly due to the poor availability or inaccessibility of pure reference standards. This study presents a new strategy of quantitative analysis of unknown and recently identified compounds. Charged aerosol detector (CAD), described as "universal detector", combined with high-performance liquid chromatography (HPLC) system proved to be a useful tool for fast and simple quantitation of PDE-5 inhibitors' analogues in a complex herbal matrix without individual reference standards available. Universal calibration was employed for calculations. Two easily obtainable reference materials - sildenafil and tadalafil - were selected as universal standards and the content of analogues was estimated with respect to their response. The error of proposed indirect determination was found to be ± 3%, which is less than enough to obtain a reliable result of the content. The elaborated method was applied for quantitative analyses of PDE-5 inhibitors and 10 analogues detected in 22 illicit dietary supplements and two bulk powdered herbal materials. All target analogues were identified using time-of-flight mass spectrometry with electrospray ionization. Obtained results indicate that the quantity of PDE-5 inhibitors in all tested samples is considered to be pharmacologically relevant. PMID:23850939

  6. Inactivation of oncogenic cAMP-specific phosphodiesterase 4D by miR-139-5p in response to p53 activation

    Cao, Bo; Wang, Kebing; Liao, Jun-Ming; Zhou, Xiang; Liao, Peng; Zeng, Shelya X; He, Meifang; Chen, Lianzhou; He, Yulong; Li, Wen; Lu, Hua

    2016-01-01

    Increasing evidence highlights the important roles of microRNAs in mediating p53’s tumor suppression functions. Here, we report miR-139-5p as another new p53 microRNA target. p53 induced the transcription of miR-139-5p, which in turn suppressed the protein levels of phosphodiesterase 4D (PDE4D), an oncogenic protein involved in multiple tumor promoting processes. Knockdown of p53 reversed these effects. Also, overexpression of miR-139-5p decreased PDE4D levels and increased cellular cAMP levels, leading to BIM-mediated cell growth arrest. Furthermore, our analysis of human colorectal tumor specimens revealed significant inverse correlation between the expression of miR-139-5p and that of PDE4D. Finally, overexpression of miR-139-5p suppressed the growth of xenograft tumors, accompanied by decrease in PDE4D and increase in BIM. These results demonstrate that p53 inactivates oncogenic PDE4D by inducing the expression of miR-139-5p. DOI: http://dx.doi.org/10.7554/eLife.15978.001 PMID:27383270

  7. Crystal Structure of the Leishmania Major Phosphodiesterase LmjPDEB1 and Insight into the Design of hte Parasite-Selective Inhibitors

    Wang,H.; Yan, Z.; Geng, J.; Kunz, S.; Seebeck, T.; Ke, H.

    2007-01-01

    Human leishmaniasis is a major public health problem in many countries, but chemotherapy is in an unsatisfactory state. Leishmania major phosphodiesterases (LmjPDEs) have been shown to play important roles in cell proliferation and apoptosis of the parasite. Thus LmjPDE inhibitors may potentially represent a novel class of drugs for the treatment of leishmaniasis. Reported here are the kinetic characterization of the LmjPDEB1 catalytic domain and its crystal structure as a complex with 3-isobutyl-1-methylxanthine (IBMX) at 1.55 Angstroms resolution. The structure of LmjPDEB1 is similar to that of human PDEs. IBMX stacks against the conserved phenylalanine and forms a hydrogen bond with the invariant glutamine, in a pattern common to most inhibitors bound to human PDEs. However, an extensive structural comparison reveals subtle, but significant differences between the active sites of LmjPDEB1 and human PDEs. In addition, a pocket next to the inhibitor binding site is found to be unique to LmjPDEB1. This pocket is isolated by two gating residues in human PDE families, but constitutes a natural expansion of the inhibitor binding pocket in LmjPDEB1. The structure particularity might be useful for the development of parasite-selective inhibitors for the treatment of leishmaniasis.

  8. Synthesis and evaluation of analogs of the phenylpyridazinone NPD-001 as potent trypanosomal TbrPDEB1 phosphodiesterase inhibitors and in vitro trypanocidals.

    Veerman, Johan; van den Bergh, Toine; Orrling, Kristina M; Jansen, Chimed; Cos, Paul; Maes, Louis; Chatelain, Eric; Ioset, Jean-Robert; Edink, Ewald E; Tenor, Hermann; Seebeck, Thomas; de Esch, Iwan; Leurs, Rob; Sterk, Geert Jan

    2016-04-01

    Trypanosomal phosphodiesterases B1 and B2 (TbrPDEB1 and TbrPDEB2) play an important role in the life cycle of Trypanosoma brucei, the causative parasite of human African trypanosomiasis (HAT), also known as African sleeping sickness. Knock down of both enzymes leads to cell cycle arrest and is lethal to the parasite. Recently, we reported the phenylpyridazinone, NPD-001, with low nanomolar IC50 values on both TbrPDEB1 (IC50: 4nM) and TbrPDEB2 (IC50: 3nM) (J. Infect. Dis.2012, 206, 229). In this study, we now report on the first structure activity relationships of a series of phenylpyridazinone analogs as TbrPDEB1 inhibitors. A selection of compounds was also shown to be anti-parasitic. Importantly, a good correlation between TbrPDEB1 IC50 and EC50 against the whole parasite was observed. Preliminary analysis of the SAR of selected compounds on TbrPDEB1 and human PDEs shows large differences which shows the potential for obtaining parasite selective PDE inhibitors. The results of these studies support the pharmacological validation of the Trypanosome PDEB family as novel therapeutic approach for HAT and provide as well valuable information for the design of potent TbrPDEB1 inhibitors that could be used for the treatment of this disease. PMID:26935942

  9. Patterns of activities of root phosphomonoesterase and phosphodiesterase in wetland plants as a function of macrophyte species and ambient phosphorus regime.

    Rejmánková, Eliska; Sirová, Dagmara; Carlson, Emily

    2011-06-01

    Phosphorus (P)-limited plants produce higher amounts of root phosphatases, but research has mostly focused on phosphomonoesterases (PMEs). Because phosphate diesters can form a significant proportion of organic P in wetlands, we aimed to determine whether wetland plants produce both root PMEs and root phosphodiesterases (PDEs), and, if so, what factors influence activities of these enzymes. We measured the activities of root PMEs and PDEs colorimetrically in a wide range of macrophytes from natural and P-enriched wetlands. Hydrolyzable P in sediments was analyzed using commercially available PMEs and PDEs. In all species, both root PMEs and PDEs were always present, and their activities were closely correlated. Sedges and broadleaved emergents had the highest activity of both enzymes, while those of floating-leaved plants were the lowest. Redundancy analysis revealed close association between root enzymes and the proportion of monoesterase- and diesterase-hydrolyzable dissolved unreactive P. Both enzymes were positively correlated with root tissue N : P ratio. Both plant and sediment traits were important when explaining differences in enzyme activities. Although the activities are related to ambient P regime, the relationship was not close enough to use root enzymes as reliable predictors of dissolved unreactive P that is hydrolyzed by sediment phosphomono- and diesterases. PMID:21714183

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

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

    2006-01-01

    perturbations, such as centrally located alpha-cells and reduced immunostaining for insulin and GLUT2 in islets from RIP-PDE3B/2 mice. Additionally, in vitro experiments revealed that the insulin secretory response to glucagon-like peptide-1 stimulation was markedly reduced in islets from high-fat-fed RIP-PDE3B......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...

  11. [The Use of Arginine Vasopressin and PhosphodiesteraseIII Inhibitor for Circulatory Shock after the Resection of a Massive Adrenal Pheochromocytoma].

    Nagamine, Yusuke; Nishinarita, Reiko; Mizutani, Kenji; Goto, Takahisa

    2016-06-01

    A 72-year-old man developed hypertensive crisis five month previously, and was diagnosed with massive adrenal pheochromocytoma, with a diameter of 14.5 cm. Preoperative echocardiography revealed normal cardiac function. The open abdominal surgery was performed under general anesthesia. During manipulation of the tumor he developed hypertension and tachycardia. Severe hypotension (50/25 mmHg) and mild bradycardia (70 beats x min(-1)) followed the resection of the tumor. In addition to volume replacement noradrenaline and adrenaline were administered, but the systolic blood pressure rose only to 60-70 mmHg. In order to treat vasodilatory shock, we started to administer arginine vasopressin infusion at 0.03 units x min(-1). His systolic blood pressure rose to 90 mmHg. The patient was transferred to the intensive care unit (ICU) postoperatively. The echocardiography revealed diffuse hypokinetic cardiac function. In order to treat cardiogenic shock, we started to administer olprinone (phosphodiesteraseIII inhibitor, infusion of 0.1 μg x kg(-1) x min(-1)). On postoperative day 2, circulatory shock improved and the patient was discharged from the ICU. In conclusion, circulatory shock after the resection of a massive pheochromocytoma was due to the down regulation of α and β adrenergic receptors. The non-adrenergic vasoconstrictor and inotrope were useful for this situation. PMID:27483661

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

    DaSilva, Jean N. [PET Centre, Centre for Addiction and Mental Health, University of Toronto, 250 College Street, Toronto, Ontario (Canada); Department of Psychiatry, University of Toronto, Toronto (Canada); Department of Pharmacology, University of Toronto, Toronto (Canada); University of Ottawa Heart Institute, Cardiac PET Centre, 40 Ruskin St., Ottawa, Ontario (Canada); Lourenco, Celia M. [PET Centre, Centre for Addiction and Mental Health, University of Toronto, 250 College Street, Toronto, Ontario (Canada); Department of Pharmacology, University of Toronto, Toronto (Canada); Meyer, Jeffrey H.; Houle, Sylvain [PET Centre, Centre for Addiction and Mental Health, University of Toronto, 250 College Street, Toronto, Ontario (Canada); Department of Psychiatry, University of Toronto, Toronto (Canada); Hussey, Douglas [PET Centre, Centre for Addiction and Mental Health, University of Toronto, 250 College Street, Toronto, Ontario (Canada); Potter, William Z. [Lilly Research Laboratories, Lilly Corporate Center, Indianapolis (United States)

    2002-12-01

    Evidence of disruptions in cAMP-mediated signaling in several neuropsychiatric disorders has led to the development of R-[{sup 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-[{sup 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-[{sup 11}C]Rolipram is thus suitable for imaging PDE4 and possibly cAMP signal transduction in the living human brain with PET. (orig.)

  13. 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.

    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). PMID:26525240

  14. A quantitative comparison of functional and anti-ischaemic effects of the phosphodiesterase-inhibitors, amrinone, milrinone and levosimendan in rabbit isolated hearts.

    Rump, A. F.; Acar, D.; Klaus, W.

    1994-01-01

    1. The functional and anti-ischaemic effects of the phosphodiesterase (PDE)-inhibitors, amrinone, milrinone and levosimendan, a new agent combining PDE-inhibitory with calcium-sensitizing properties, were investigated in rabbit isolated hearts (Langendorff, constant pressure: 70 cmH2O, Tyrode solution, Ca2+ 1.8 mmol l-1, 37 degrees C). Anti-ischaemic effects were studied in electrically-driven hearts (200 beats min-1). Acute regional ischaemia was induced by ligature of a branch of the circumflex coronary artery and quantified from epicardial NADH-fluorescence photography. 2. Cumulative concentration-response curves in spontaneously beating hearts in the presence of isoprenaline (10(-10) M), showed a higher inotropic and coronary vasodilator potency for levosimendan (EC50: 7 x 10(-7) M) compared to milrinone (EC50: 7.7 x 10(-6) M) or amrinone (EC50: 2 x 10(-5) M). Although the maximal coronary dilator activity was similar for the three agents, the maximal inotropic and chronotropic effects were lower for levosimendan than for amrinone or milrinone (P 0.05). 4. It is concluded that amrinone and milrinone possess similar functional profiles in rabbit isolated hearts and a higher inotropic and chronotropic efficacy than levosimendan.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7921599

  15. Discovery of Potent and Selective Inhibitors of Phosphodiesterase 1 for the Treatment of Cognitive Impairment Associated with Neurodegenerative and Neuropsychiatric Diseases.

    Li, Peng; Zheng, Hailin; Zhao, Jun; Zhang, Lei; Yao, Wei; Zhu, Hongwen; Beard, J David; Ida, Koh; Lane, Weston; Snell, Gyorgy; Sogabe, Satoshi; Heyser, Charles J; Snyder, Gretchen L; Hendrick, Joseph P; Vanover, Kimberly E; Davis, Robert E; Wennogle, Lawrence P

    2016-02-11

    A diverse set of 3-aminopyrazolo[3,4-d]pyrimidinones was designed and synthesized. The structure-activity relationships of these polycyclic compounds as phosphodiesterase 1 (PDE1) inhibitors were studied along with their physicochemical and pharmacokinetic properties. Systematic optimizations of this novel scaffold culminated in the identification of a clinical candidate, (6aR,9aS)-2-(4-(6-fluoropyridin-2-yl)benzyl)-5-methyl-3-(phenylamino)-5,6a,7,8,9,9a-hexahydrocyclopenta[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4-(2H)-one phosphate (ITI-214), which exhibited picomolar inhibitory potency for PDE1, demonstrated excellent selectivity against all other PDE families and showed good efficacy in vivo. Currently, this investigational new drug is in Phase I clinical development and being considered for the treatment of several indications including cognitive deficits associated with schizophrenia and Alzheimer's disease, movement disorders, attention deficit and hyperactivity disorders, and other central nervous system (CNS) and non-CNS disorders. PMID:26789933

  16. Increased density of DISC1-immunoreactive oligodendroglial cells in fronto-parietal white matter of patients with paranoid schizophrenia.

    Bernstein, Hans-Gert; Jauch, Esther; Dobrowolny, Henrik; Mawrin, Christian; Steiner, Johann; Bogerts, Bernhard

    2016-09-01

    Profound white matter abnormalities have repeatedly been described in schizophrenia, which involve the altered expression of numerous oligodendrocyte-associated genes. Transcripts of the disrupted-in-schizophrenia 1 (DISC1) gene, a key susceptibility factor in schizophrenia, have recently been shown to be expressed by oligodendroglial cells and to negatively regulate oligodendrocyte differentiation and maturation. To learn more about the putative role(s) of oligodendroglia-associated DISC1 in schizophrenia, we analyzed the density of DISC1-immunoreactive oligodendrocytes in the fronto-parietal white matter in postmortem brains of patients with schizophrenia. Compared with controls (N = 12) and cases with undifferentiated/residual schizophrenia (N = 6), there was a significantly increased density of DISC1-expressing glial cells in paranoid schizophrenia (N = 12), which unlikely resulted from neuroleptic treatment. Pathophysiologically, over-expression of DISC1 protein(s) in white matter oligodendrocytes might add to the reduced levels of two myelin markers, 2',3'-cyclic-nucleotide 3'-phosphodiesterase and myelin basic protein in schizophrenia. Moreover, it might significantly contribute to cell cycle abnormalities as well as to deficits in oligodendroglial cell differentiation and maturation found in schizophrenia. PMID:26315603

  17. Proliferation of differentiated glial cells in the brain stem.

    Barradas, P C; Cavalcante, L A

    1998-02-01

    Classical studies of macroglial proliferation in muride rodents have provided conflicting evidence concerning the proliferating capabilities of oligodendrocytes and microglia. Furthermore, little information has been obtained in other mammalian orders and very little is known about glial cell proliferation and differentiation in the subclass Metatheria although valuable knowledge may be obtained from the protracted period of central nervous system maturation in these forms. Thus, we have studied the proliferative capacity of phenotypically identified brain stem oligodendrocytes by tritiated thymidine radioautography and have compared it with known features of oligodendroglial differentiation as well as with proliferation of microglia in the opossum Didelphis marsupialis. We have detected a previously undescribed ephemeral, regionally heterogeneous proliferation of oligodendrocytes expressing the actin-binding, ensheathment-related protein 2'3'-cyclic nucleotide 3'-phosphodiesterase (CNPase), that is not necessarily related to the known regional and temporal heterogeneity of expression of CNPase in cell bodies. On the other hand, proliferation of microglia tagged by the binding of Griffonia simplicifolia B4 isolectin, which recognizes an alpha-D-galactosyl-bearing glycoprotein of the plasma membrane of macrophages/microglia, is known to be long lasting, showing no regional heterogeneity and being found amongst both ameboid and differentiated ramified cells, although at different rates. The functional significance of the proliferative behavior of these differentiated cells is unknown but may provide a low-grade cell renewal in the normal brain and may be augmented under pathological conditions. PMID:9686148

  18. Proliferation of differentiated glial cells in the brain stem

    Barradas P.C.

    1998-01-01

    Full Text Available Classical studies of macroglial proliferation in muride rodents have provided conflicting evidence concerning the proliferating capabilities of oligodendrocytes and microglia. Furthermore, little information has been obtained in other mammalian orders and very little is known about glial cell proliferation and differentiation in the subclass Metatheria although valuable knowledge may be obtained from the protracted period of central nervous system maturation in these forms. Thus, we have studied the proliferative capacity of phenotypically identified brain stem oligodendrocytes by tritiated thymidine radioautography and have compared it with known features of oligodendroglial differentiation as well as with proliferation of microglia in the opossum Didelphis marsupialis. We have detected a previously undescribed ephemeral, regionally heterogeneous proliferation of oligodendrocytes expressing the actin-binding, ensheathment-related protein 2'3'-cyclic nucleotide 3'-phosphodiesterase (CNPase, that is not necessarily related to the known regional and temporal heterogeneity of expression of CNPase in cell bodies. On the other hand, proliferation of microglia tagged by the binding of Griffonia simplicifolia B4 isolectin, which recognizes an alpha-D-galactosyl-bearing glycoprotein of the plasma membrane of macrophages/microglia, is known to be long lasting, showing no regional heterogeneity and being found amongst both ameboid and differentiated ramified cells, although at different rates. The functional significance of the proliferative behavior of these differentiated cells is unknown but may provide a low-grade cell renewal in the normal brain and may be augmented under pathological conditions.

  19. Heterogeneous patterns of oligodendroglial differentiation in the forebrain of the opossum Didelphis marsupialis.

    Barradas, P C; Gomes, S S; Cavalcante, L A

    1998-01-01

    The differentiation of oligodendrocytes in the forebrain of the opossum (Didelphis marsupialis) has been studied by the immunohistochemical identification of 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) and by the autoradiographic detection of the uptake of 3H-thymidine. CNPase is expressed early in oligodendroglia somata and fibre sheaths (myelin) in the forebrain and its persistence in the cell bodies is regionally heterogeneous, being ephemeral in cells within the optic pathway, supraoptic decussation, and posterior commissure, of intermediate duration in the mamillo-thalamic fascicle, and stria medullaris, and long-lasting in other diencephalic and in telencephalic tracts. In the cerebral cortex, most CNPase+ cells have small somata and multiple processes (types I and II). CNPase-expressing oligodendrocytes are also regionally heterogeneous in terms of proliferative capability, which could not be detected in forebrain tracts or diencephalon, but has appeared in a small proportion of cells in the neocortical white matter and in the fimbria. Our findings provide additional evidence in favour of the heterogeneity of oligodendrocytes. PMID:9530996

  20. Myocilin is involved in NgR1/Lingo-1-mediated oligodendrocyte differentiation and myelination of the optic nerve.

    Kwon, Heung Sun; Nakaya, Naoki; Abu-Asab, Mones; Kim, Hong Sug; Tomarev, Stanislav I

    2014-04-16

    Myocilin is a secreted glycoprotein that belongs to a family of olfactomedin domain-containing proteins. Although myocilin is detected in several ocular and nonocular tissues, the only reported human pathology related to mutations in the MYOCILIN gene is primary open-angle glaucoma. Functions of myocilin are poorly understood. Here we demonstrate that myocilin is a mediator of oligodendrocyte differentiation and is involved in the myelination of the optic nerve in mice. Myocilin is expressed and secreted by optic nerve astrocytes. Differentiation of optic nerve oligodendrocytes is delayed in Myocilin-null mice. Optic nerves of Myocilin-null mice contain reduced levels of several myelin-associated proteins including myelin basic protein, myelin proteolipid protein, and 2'3'-cyclic nucleotide 3'-phosphodiesterase compared with those of wild-type littermates. This leads to reduced myelin sheath thickness of optic nerve axons in Myocilin-null mice compared with wild-type littermates, and this difference is more pronounced at early postnatal stages compared with adult mice. Myocilin also affects differentiation of oligodendrocyte precursors in vitro. Its addition to primary cultures of differentiating oligodendrocyte precursors increases levels of tested markers of oligodendrocyte differentiation and stimulates elongation of oligodendrocyte processes. Myocilin stimulation of oligodendrocyte differentiation occurs through the NgR1/Lingo-1 receptor complex. Myocilin physically interacts with Lingo-1 and may be considered as a Lingo-1 ligand. Myocilin-induced elongation of oligodendrocyte processes may be mediated by activation of FYN and suppression of RhoA GTPase. PMID:24741044

  1. CNPase Expression in Olfactory Ensheathing Cells

    Christine Radtke

    2011-01-01

    Full Text Available A large body of work supports the proposal that transplantation of olfactory ensheathing cells (OECs into nerve or spinal cord injuries can promote axonal regeneration and remyelination. Yet, some investigators have questioned whether the transplanted OECs associate with axons and form peripheral myelin, or if they recruit endogenous Schwann cells that form myelin. Olfactory bulbs from transgenic mice expressing the enhanced green fluorescent protein (eGFP under the control of the 2-3-cyclic nucleotide 3-phosphodiesterase (CNPase promoter were studied. CNPase is expressed in myelin-forming cells throughout their lineage. We examined CNPase expression in both in situ in the olfactory bulb and in vitro to determine if OECs express CNPase commensurate with their myelination potential. eGFP was observed in the outer nerve layer of the olfactory bulb. Dissociated OECs maintained in culture had both intense eGFP expression and CNPase immunostaining. Transplantation of OECs into transected peripheral nerve longitudinally associated with the regenerated axons. These data indicate that OECs in the outer nerve layer of the olfactory bulb of CNPase transgenic mice express CNPase. Thus, while OECs do not normally form myelin on olfactory nerve axons, their expression of CNPase is commensurate with their potential to form myelin when transplanted into injured peripheral nerve.

  2. The epitope recognized by a monoclonal antibody in the myelin-associated protein CNP.

    Stricker, R; Kalbacher, H; Reiser, G

    1997-08-18

    The epitope recognized by a monoclonal antibody (MAb-46-1) directed against the myelin-associated protein CNP (2',3'-cyclic nucleotide 3'-phosphodiesterase; EC 3.1.4.37) from several species was characterized. MAb-46-1 can be employed for immunoprecipitation, immunostaining in Western blots and in immunohistochemistry. Short peptides derived from the human CNP1 peptide sequence were synthesized and used in enzyme linked immunosorbent assays to test the reactivity of MAb-46-1. Coarse screening experiments enabled us to localize the epitope recognized by MAb-46-1 to the amino acid residues 9 to 19 close to the N-terminus. Further investigations using shorter peptides comprising this part of the protein allowed us to identify a 9 amino acid residue long peptide (amino acids 11 to 19: ELQFPFLQD) which represents the minimal epitope recognized by MAb-46-1, probably through a 3-dimensional structure and less likely a straight linear peptide. The epitope seems to be stabilized also by the attached amino acids 7 to 10 (KDKP). The peptide sequence 9-19 is conserved in all CNP sequences described so far. Thus, MAb-46-1 might be of general usefulness for further studies of the not yet identified function of the myelin-associated protein CNP. PMID:9268698

  3. Mice with conditional inactivation of fibroblast growth factor receptor-2 signaling in oligodendrocytes have normal myelin but display dramatic hyperactivity when combined with Cnp1 inactivation.

    Kaga, Y; Shoemaker, W J; Furusho, M; Bryant, M; Rosenbluth, J; Pfeiffer, S E; Oh, L; Rasband, M; Lappe-Siefke, C; Yu, K; Ornitz, D M; Nave, K-A; Bansal, R

    2006-11-22

    Fibroblast growth factor receptors (Fgfr) comprise a widely expressed family of developmental regulators implicated in oligodendrocyte (OL) maturation of the CNS. Fgfr2 is expressed by OLs in myelinated fiber tracks. In vitro, Fgfr2 is highly upregulated during OL terminal differentiation, and its activation leads to enhanced growth of OL processes and the formation of myelin-like membranes. To investigate the in vivo function of Fgfr2 signaling by myelinating glial cells, we inactivated the floxed Fgfr2 gene in mice that coexpress Cre recombinase (cre) as a knock-in gene into the OL-specific 2',3'-cyclic nucleotide phosphodiesterase (Cnp1) locus. Surprisingly, no obvious defects were detected in brain development of these conditional mutants, including the number of OLs, the onset and extent of myelination, the ultrastructure of myelin, and the expression level of myelin proteins. However, unexpectedly, a subset of these conditional Fgfr2 knock-out mice that are homozygous for cre and therefore are also Cnp1 null, displayed a dramatic hyperactive behavior starting at approximately 2 weeks of age. This hyperactivity was abolished by treatment with dopamine receptor antagonists or catecholamine biosynthesis inhibitors, suggesting that the symptoms involve a dysregulation of the dopaminergic system. Although the molecular mechanisms are presently unknown, this novel mouse model of hyperactivity demonstrates the potential involvement of OLs in neuropsychiatric disorders, as well as the nonpredictable role of genetic interactions in the behavioral phenotype of mice. PMID:17122059

  4. Mitochondrial localization of CNP2 is regulated by phosphorylation of the N-terminal targeting signal by PKC: implications of a mitochondrial function for CNP2 in glial and non-glial cells.

    Lee, John; O'Neill, Ryan C; Park, Min Woo; Gravel, Michel; Braun, Peter E

    2006-03-01

    Both 2',3'-cyclic nucleotide-3'-phosphodiesterase (CNP) isoforms are abundantly expressed in myelinating cells. CNP2 differs from CNP1 by a 20 amino acid N-terminal extension and is also expressed at much lower levels in non-myelinating tissues. The functional role of CNP2, apart from CNP1, and the significance for CNP2 expression in non-myelinating tissues are unknown. Here, we demonstrate that CNP2 is translocated to mitochondria by virtue of a mitochondrial targeting signal at the N-terminus. PKC-mediated phosphorylation of the targeting signal inhibits CNP2 translocation to mitochondria, thus retaining it in the cytoplasm. CNP2 is imported into mitochondria and the targeting signal cleaved, yielding a mature, truncated form similar in size to CNP1. CNP2 is entirely processed in adult liver and embryonic brain, indicating that it is localized specifically to mitochondria in non-myelinating cells. Our results point to a broader biological role for CNP2 in mitochondria that is likely to be different from its specific role in the cytoplasm, along with CNP1, during myelination. PMID:16343930

  5. Early ultrastructural defects of axons and axon-glia junctions in mice lacking expression of Cnp1.

    Edgar, Julia M; McLaughlin, Mark; Werner, Hauke B; McCulloch, Mailis C; Barrie, Jennifer A; Brown, Angus; Faichney, Andrew Blyth; Snaidero, Nicolas; Nave, Klaus-Armin; Griffiths, Ian R

    2009-12-01

    Most axons in the central nervous system (CNS) are surrounded by a multilayered myelin sheath that promotes fast, saltatory conduction of electrical impulses. By insulating the axon, myelin also shields the axoplasm from the extracellular milieu. In the CNS, oligodendrocytes provide support for the long-term maintenance of myelinated axons, independent of the myelin sheath. Here, we use electron microscopy and morphometric analyses to examine the evolution of axonal and oligodendroglial changes in mice deficient in 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP) and in mice deficient in both CNP and proteolipid protein (PLP/DM20). We show that CNP is necessary for the formation of a normal inner tongue process of oligodendrocytes that myelinate small diameter axons. We also show that axonal degeneration in Cnp1 null mice is present very early in postnatal life. Importantly, compact myelin formed by transplanted Cnp1 null oligodendrocytes induces the same degenerative changes in shiverer axons that normally are dysmyelinated but structurally intact. Mice deficient in both CNP and PLP develop a more severe axonal phenotype than either single mutant, indicating that the two oligodendroglial proteins serve distinct functions in supporting the myelinated axon. These observations support a model in which the trophic functions of oligodendrocytes serve to offset the physical shielding of axons by myelin membranes. PMID:19459211

  6. Growth and differentiation of neural stem cells in a three-dimensional collagen gel scaffold

    Fei Huang; Qiang Shen; Jitong Zhao

    2013-01-01

    Collagen protein is an ideal scaffold material for the transplantation of neural stem cells. In this study, rat neural stem cells were seeded into a three-dimensional collagen gel scaffold, with suspension cultured neural stem cells being used as a control group. Neural stem cells, which were cultured in medium containing epidermal growth factor and basic fibroblast growth factor, actively expanded and formed neurospheres in both culture groups. In serum-free medium conditions, the processes extended from neurospheres in the collagen gel group were much longer than those in the suspension culture group. Immunofluorescence staining showed that neurospheres cultured in collagen gels were stained positive for nestin and differentiated cells were stained positive for the neuronal marker βIII-tubulin, the astrocytic marker glial fibrillary acidic protein and the oligodendrocytic marker 2',3'-cyclic nucleotide 3'-phosphodiesterase. Compared with neurospheres cultured in suspension, the differentiation potential of neural stem cells cultured in collagen gels increased, with the formation of neurons at an early stage. Our results show that the three-dimensional collagen gel culture system is superior to suspension culture in the proliferation, differentiation and process outgrowth of neural stem cells.

  7. Severe Hypomyelination and Developmental Defects Are Caused in Mice Lacking Protein Arginine Methyltransferase 1 (PRMT1) in the Central Nervous System.

    Hashimoto, Misuzu; Murata, Kazuya; Ishida, Junji; Kanou, Akihiko; Kasuya, Yoshitoshi; Fukamizu, Akiyoshi

    2016-01-29

    Protein arginine methyltransferase 1 (PRMT1) is involved in cell proliferation, DNA damage response, and transcriptional regulation. Although PRMT1 is extensively expressed in the CNS at embryonic and perinatal stages, the physiological role of PRMT1 has been poorly understood. Here, to investigate the primary function of PRMT1 in the CNS, we generated CNS-specific PRMT1 knock-out mice by the Cre-loxP system. These mice exhibited postnatal growth retardation with tremors, and most of them died within 2 weeks after birth. Brain histological analyses revealed prominent cell reduction in the white matter tracts of the mutant mice. Furthermore, ultrastructural analysis demonstrated that myelin sheath was almost completely ablated in the CNS of these animals. In agreement with hypomyelination, we also observed that most major myelin proteins including myelin basic protein (MBP), 2',3'-cyclic-nucleotide 3'-phosphodiesterase (CNPase), and myelin-associated glycoprotein (MAG) were dramatically decreased, although neuronal and astrocytic markers were preserved in the brain of CNS-specific PRMT1 knock-out mice. These animals had a reduced number of OLIG2(+) oligodendrocyte lineage cells in the white matter. We found that expressions of transcription factors essential for oligodendrocyte specification and further maturation were significantly suppressed in the brain of the mutant mice. Our findings provide evidence that PRMT1 is required for CNS development, especially for oligodendrocyte maturation processes. PMID:26637354

  8. cAMP/PKA/CREB/GLT1 signaling involved in the antidepressant-like effects of phosphodiesterase 4D inhibitor (GEBR-7b in rats

    Liu X

    2016-01-01

    Full Text Available Xu Liu,1,2,* Haibiao Guo,1,* Mohammad Daud SOM Sayed,3,4,* Yang Lu,3,4,* Ting Yang,5,* Dongsheng Zhou,6 Zhongming Chen,6 Haitao Wang,1 Chuang Wang,3,4 Jiangping Xu1 1Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong, 2Department of Pharmacy, General Hospital of Chinese People’s Armed Police Forces, Beijing, 3Ningbo Key Laboratory of Behavioral Neuroscience, 4Zhejiang Provincial Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, Ningbo, Zhejiang, 5Department of Pediatrics, The Affiliated Hospital of Ningbo University, Ningbo, Zhejiang, 6Department of Geriatric Psychiatry, Ningbo Kangning Hospital, Ningbo, Zhejiang, People’s Republic of China *These authors contributed equally to this work Objectives: GEBR-7b, a potential phosphodiesterase 4D inhibitor, has been shown to have memory-enhancing effects in rodents. However, it is still unknown whether GEBR-7b also has the antidepressant-like effects in rats. Herein, we examined the potential of GEBR-7b to ­attenuate depression-like behaviors in the rat model of depression induced by chronic unpredictable stress (CUS. Next, we also investigated the alterations of cyclic adenosine monophosphate (cAMP, protein kinase A (PKA catalytic subunit (PKAca, cAMP response element-binding (CREB, and glutamate transporter 1 (GLT1 levels produced by GEBR-7b in the rats model of depression.Methods: Effects of GEBR-7b on CUS (35 days-induced depression-like behaviors were examined by measuring immobility time in the forced swimming test (FST. Hippocampal cAMP levels were examined by enzyme-linked immunosorbent assay, whereas PKAca, phosphorylation of CREB (pCREB, CREB, and GLT1 in the hippocampus of rats were subjected to Western blot analysis.Results: CUS exposure caused a depression-like behavior evidenced by the increased immobility time in FST. Depression-like behavior induced by CUS was

  9. Further evaluation of [11C]MP-10 as a radiotracer for phosphodiesterase 10A: PET imaging study in rhesus monkeys and brain tissue metabolite analysis.

    Lin, Shu-Fei; Labaree, David; Chen, Ming-Kai; Holden, Daniel; Gallezot, Jean-Dominique; Kapinos, Michael; Teng, Jo-Ku; Najafzadeh, Soheila; Plisson, Christophe; Rabiner, Eugenii A; Gunn, Roger N; Carson, Richard E; Huang, Yiyun

    2015-02-01

    [(11)C]MP-10 is a potent and specific PET tracer previously shown to be suitable for imaging the phosphodiesterase 10A (PDE10A) in baboons with reversible kinetics and high specific binding. However, another report indicated that [(11)C]MP-10 displayed seemingly irreversible kinetics in rhesus monkeys, potentially due to the presence of a radiolabeled metabolite capable of penetrating the blood-brain-barrier (BBB) into the brain. This study was designed to address the discrepancies between the species by re-evaluating [(11)C]MP-10 in vivo in rhesus monkey with baseline scans to assess tissue uptake kinetics and self-blocking scans with unlabeled MP-10 to determine binding specificity. Ex vivo studies with one rhesus monkey and 4 Sprague-Dawley rats were also performed to investigate the presence of radiolabeled metabolites in the brain. Our results indicated that [(11)C]MP-10 displayed reversible uptake kinetics in rhesus monkeys, albeit slower than in baboons. Administration of unlabeled MP-10 reduced the binding of [(11)C]MP-10 in a dose-dependent manner in all brain regions including the cerebellum. Consequently, the cerebellum appeared not to be a suitable reference tissue in rhesus monkeys. Regional volume of distribution (VT) was mostly reliably derived with the multilinear analysis (MA1) method. In ex vivo studies in the monkey and rats only negligible amount of radiometabolites was seen in the brain of either species. In summary, results from the present study strongly support the suitability of [(11)C]MP-10 as a radiotracer for PET imaging and quantification of PDE10A in nonhuman primates. PMID:25450608

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

    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.

  11. Synergistic effect between 5-HT4 receptor agonist and phosphodiesterase 4-inhibitor in releasing acetylcholine in pig gastric circular muscle in vitro.

    Lefebvre, Romain A; Van Colen, Inge; Pauwelyn, Vicky; De Maeyer, Joris H

    2016-06-15

    5-HT4 receptor agonists have a gastroprokinetic effect by facilitating acetylcholine release from cholinergic nerves innervating gastrointestinal smooth muscle. The role of phosphodiesterase (PDE) 4 in the signal transduction pathway of the 5-HT4 receptors located on the cholinergic neurons towards the circular muscle layer in pig stomach was investigated by analysis of acetylcholine release. Circular muscle strips were prepared from pig proximal stomach and tritium outflow, induced by electrical field stimulation, was studied as a marker for acetylcholine release after incubation with [(3)H]-choline. The PDE4-inhibitor roflumilast concentration-dependently (0.1-1µM) enhanced the facilitating effect of a submaximally effective concentration of the 5-HT4 receptor agonist prucalopride (0.01µM) on electrically induced acetylcholine release. Roflumilast (0.3µM) enhanced acetylcholine release per se but in the combined presence of roflumilast and prucalopride, acetylcholine release was enhanced more than the sum of the effect of the 2 compounds alone. The 5-HT4 receptor agonist velusetrag concentration-dependently (0.01-0.1µM) enhanced acetylcholine release; the effect of the minimally effective concentration (0.01µM) was significantly enhanced by 1µM of the PDE4-inhibitor rolipram, again to a level higher than the sum of the effect of the 2 compounds alone. The synergistic effect between 5-HT4 receptor agonists and PDE4-inhibitors demonstrates that the intracellular pathway of the 5-HT4 receptors located on cholinergic neurons towards pig gastric circular muscle is controlled by PDE4. Combining a 5-HT4 receptor agonist with a PDE4-inhibitor might thus enhance its gastroprokinetic effect. PMID:27060014

  12. Evidence that insulin and isoprenaline activate the cGMP-inhibited low-Km cAMP phosphodiesterase in rat fat cells by phosphorylation

    Incubation of intact rat fat cells with maximally effective concentrations of insulin (1 nM, 12 min) or isoprenaline (300 nM, 3 min) increased particulate cGMP- and cilostamide-inhibited, low-Km cAMP phosphodiesterase (cAMP-PDE) activity by about 50% and 100%, respectively. In 32P-labeled cells, these agents induced serine 32P-phosphorylation of a 135-kDa particulate protein and, to a variable and lesser extent, a 44-kDa protein, which were selectively immunoprecipitated by anti-cAMP-PDE, as analyzed by SDS/PAGE and autoradiography. In the absence of hormonal stimulation, little phosphorylation was detected (less than 10% of that with the hormones). The two phosphoproteins were identified as cAMP-PDE or a closely related molecule (in the case of the 44-kDa species, perhaps a proteolytic fragment) since (i) amounts of 32P in the immunoprecipitated 135-kDa protein paralleled enzyme inactivation, (ii) prior incubation of the anti-cAMP-PDE with the pure rat or bovine enzyme selectively blocked the immunoprecipitation of the phosphoproteins, (iii) 135- and 44-kDa proteins reacted with the anti-cAMP-PDE on Western immunoblots, and (iv) the two phosphoproteins copurified with cAMP-PDE activity through DEAE-Sephacel chromatography and were isolated by highly selective affinity chromatography on cilostamide-agarose. Thus, in fat cells, catecholamine- and insulin-induced activation of the cAMP-PDE may be mediated via phosphorylation by cAMP-dependent protein kinase and an insulin-activated serine protein kinase, respectively

  13. Ab Initio QM/MM Study Shows a Highly Dissociated SN2 Hydrolysis Mechanism for the cGMP-Specific Phosphodiesterase-5.

    Li, Zhe; Wu, Yinuo; Feng, Ling-Jun; Wu, Ruibo; Luo, Hai-Bin

    2014-12-01

    Phosphodiesterases (PDEs) are the sole enzymes hydrolyzing the important second messengers cGMP and cAMP and have been identified as therapeutic targets for several diseases. The most successful examples are PDE5 inhibitors (i.e., sildenafil and tadalafil), which have been approved for the treatment of male erectile dysfunction and pulmonary hypertension. However, the side effects mostly due to nonselective inhibition toward other PDE isoforms, set back the clinical usage of PDE5 inhibitors. Until now, the exact catalytic mechanism of the substrate cGMP by PDE5 is still unclear. Herein, the first computational study on the catalytic hydrolysis mechanism of cGMP for PDE5 (catalytic domain) is performed by employing the state-of-the-art ab initio quantum mechanics/molecular mechanics (QM/MM) molecular dynamics (MD) simulations. Our simulations show a SN2 type reaction procedure via a highly dissociated transition state with a reaction barrier of 8.88 kcal/mol, which is quite different from the previously suggested hydrolysis mechanism of cAMP for PDE4. Furthermore, the subsequent ligand exchange and the release of the product GMP have also been investigated by binding energy analysis and MD simulations. It is deduced that ligand exchange would be the rate-determining step of the whole reaction, which is consistent with many previous experimental results. The obtained mechanistic insights should be valuable for not only the rational design of more specific inhibitors toward PDE5 but also understanding the general hydrolysis mechanism of cGMP-specific PDEs. PMID:26583228

  14. HPRT-deficiency dysregulates cAMP-PKA signaling and phosphodiesterase 10A expression: mechanistic insight and potential target for Lesch-Nyhan Disease?

    Ghiabe-Henri Guibinga

    Full Text Available Lesch-Nyhan Disease (LND is the result of mutations in the X-linked gene encoding the purine metabolic enzyme, hypoxanthine guanine phosphoribosyl transferase (HPRT. LND gives rise to severe neurological anomalies including mental retardation, dystonia, chorea, pyramidal signs and a compulsive and aggressive behavior to self injure. The neurological phenotype in LND has been shown to reflect aberrant dopaminergic signaling in the basal ganglia, however there are little data correlating the defect in purine metabolism to the neural-related abnormalities. In the present studies, we find that HPRT-deficient neuronal cell lines have reduced CREB (cAMP response element-binding protein expression and intracellular cyclic AMP (cAMP, which correlates with attenuated CREB-dependent transcriptional activity and a reduced phosphorylation of protein kinase A (PKA substrates such as synapsin (p-syn I. Of interest, we found increased expression of phosphodiesterase 10A (PDE10A in HPRT-deficient cell lines and that the PDE10 inhibitor papaverine and PDE10A siRNA restored cAMP/PKA signaling. Furthermore, reconstitution of HPRT expression in mutant cells partly increased cAMP signaling synapsin phosphorylation. In conclusion, our data show that HPRT-deficiency alters cAMP/PKA signaling pathway, which is in part due to the increased of PDE10A expression and activity. These findings suggest a mechanistic insight into the possible causes of LND and highlight PDE10A as a possible therapeutic target for this intractable neurological disease.

  15. Simulating biochemical physics with computers: 1. Enzyme catalysis by phosphotriesterase and phosphodiesterase; 2. Integration-free path-integral method for quantum-statistical calculations

    Wong, Kin-Yiu

    We have simulated two enzymatic reactions with molecular dynamics (MD) and combined quantum mechanical/molecular mechanical (QM/MM) techniques. One reaction is the hydrolysis of the insecticide paraoxon catalyzed by phosphotriesterase (PTE). PTE is a bioremediation candidate for environments contaminated by toxic nerve gases (e.g., sarin) or pesticides. Based on the potential of mean force (PMF) and the structural changes of the active site during the catalysis, we propose a revised reaction mechanism for PTE. Another reaction is the hydrolysis of the second-messenger cyclic adenosine 3'-5'-monophosphate (cAMP) catalyzed by phosphodiesterase (PDE). Cyclicnucleotide PDE is a vital protein in signal-transduction pathways and thus a popular target for inhibition by drugs (e.g., ViagraRTM). A two-dimensional (2-D) free-energy profile has been generated showing that the catalysis by PDE proceeds in a two-step SN2-type mechanism. Furthermore, to characterize a chemical reaction mechanism in experiment, a direct probe is measuring kinetic isotope effects (KIEs). KIEs primarily arise from internuclear quantum-statistical effects, e.g., quantum tunneling and quantization of vibration. To systematically incorporate the quantum-statistical effects during MD simulations, we have developed an automated integration-free path-integral (AIF-PI) method based on Kleinert's variational perturbation theory for the centroid density of Feynman's path integral. Using this analytic method, we have performed ab initio pathintegral calculations to study the origin of KIEs on several series of proton-transfer reactions from carboxylic acids to aryl substituted alpha-methoxystyrenes in water. In addition, we also demonstrate that the AIF-PI method can be used to systematically compute the exact value of zero-point energy (beyond the harmonic approximation) by simply minimizing the centroid effective potential.

  16. The Effect of a Selective Inhibitor of Phosphodiesterase-9 on Oxidative Stress, Inflammation and Cytotoxicity in Neutrophils from Patients with Sickle Cell Anaemia.

    Barbosa, Maritza Cavalcante; de Jesus Dos Santos, Talyta Ellen; Santos, Thayna Nogueira Dos; Pedrosa, Alano Martins; Elias, Darcielle Bruna Dias; Leal, Luzia Kalyne Almeida Moreira; de Araújo Lopes, Amanda; Sasahara, Greyce Luri; Gonçalves Lemes, Romélia Pinheiro

    2016-04-01

    The aim of the study was to investigate the possible anti-inflammatory and antioxidant effects of BAY 73-6691 on neutrophils from SCA patients. This study included 35 patients with a molecular diagnosis of SCA, whose neutrophils were isolated and treated with BAY 73-6691 at the concentrations 100, 10, 1.0 and 0.1 μg/mL. LDH release and MTT assays were performed to verify cell viability. To evaluate oxidative stress, the following parameters were determined by spectrophotometric assays: NO and malondialdehyde (MDA) levels and activity of catalase, superoxide dismutase (SOD) and glutathione peroxidase (GPx). As inflammatory markers, myeloperoxidase (MPO) levels were evaluated by colorimetric assay and TNF-α by enzyme immunoassay. The results showed that neutrophils from SCA patients not treated with hydroxyurea (HU) had significantly lower NO levels and catalase and SOD activity, as well as significantly higher MDA, MPO and TNF-α levels when compared with neutrophils from SCA patients treated with HU and neutrophils from control group. Treatment of SCA neutrophils with BAY 73-6691 resulted in 94%, 200% and 168% increase in NOx levels, SOD and catalase activity, respectively. In addition, there was a reduction of approximately 46% and 45% in TNF-α and MPO levels, respectively. In SCAHU neutrophils, there was a 30% and 44% increase in NOx levels and SOD activity, respectively, and a 28% and 37% decrease in TNF-α and MPO levels, respectively. However, these effects were observed at cytotoxic doses only. The results of this study are original and demonstrate that inhibition of phosphodiesterase-9 in neutrophils from SCA patients with BAY 73-6691 was able to increase the NO bioavailability and attenuate oxidative stress and inflammation in neutrophils from patients not treated with HU. PMID:26346295

  17. 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

    Park, Tae Yong; Jeong, Hyeong Guk; Park, Jong Jin; Chae, Ji Yun; Kim, Jong Wook; Oh, Mi Mi; Park, Hong Seok; Kim, Je Jong

    2016-01-01

    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 30° (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 30°. PMID:27169128

  18. Synthesis, 18F-Radiolabelling and Biological Characterization of Novel Fluoroalkylated Triazine Derivatives for in Vivo Imaging of Phosphodiesterase 2A in Brain via Positron Emission Tomography

    Susann Schröder

    2015-05-01

    Full Text Available Phosphodiesterase 2A (PDE2A is highly and specifically expressed in particular brain regions that are affected by neurological disorders and in certain tumors. Development of a specific PDE2A radioligand would enable molecular imaging of the PDE2A protein via positron emission tomography (PET. Herein we report on the syntheses of three novel fluoroalkylated triazine derivatives (TA2–4 and on the evaluation of their effect on the enzymatic activity of human PDE2A. The most potent PDE2A inhibitors were 18F-radiolabelled ([18F]TA3 and [18F]TA4 and investigated regarding their potential as PET radioligands for imaging of PDE2A in mouse brain. In vitro autoradiography on rat brain displayed region-specific distribution of [18F]TA3 and [18F]TA4, which is consistent with the expression pattern of PDE2A protein. Metabolism studies of both [18F]TA3 and [18F]TA4 in mice showed a significant accumulation of two major radiometabolites of each radioligand in brain as investigated by micellar radio-chromatography. Small-animal PET/MR studies in mice using [18F]TA3 revealed a constantly increasing uptake of activity in the non-target region cerebellum, which may be caused by the accumulation of brain penetrating radiometabolites. Hence, [18F]TA3 and [18F]TA4 are exclusively suitable for in vitro investigation of PDE2A. Nevertheless, further structural modification of these promising radioligands might result in metabolically stable derivatives.

  19. Theophylline Represses IL-8 Secretion from Airway Smooth Muscle Cells Independently of Phosphodiesterase Inhibition. Novel Role as a Protein Phosphatase 2A Activator.

    Patel, Brijeshkumar S; Rahman, Md Mostafizur; Rumzhum, Nowshin N; Oliver, Brian G; Verrills, Nicole M; Ammit, Alaina J

    2016-06-01

    Theophylline is an old drug experiencing a renaissance owing to its beneficial antiinflammatory effects in chronic respiratory diseases, such as asthma and chronic obstructive pulmonary disease. Multiple modes of antiinflammatory action have been reported, including inhibition of the enzymes that degrade cAMP-phosphodiesterase (PDE). Using primary cultures of airway smooth muscle (ASM) cells, we recently revealed that PDE4 inhibitors can potentiate the antiinflammatory action of β2-agonists by augmenting cAMP-dependent expression of the phosphatase that deactivates mitogen-activated protein kinase (MAPK)-MAPK phosphatase (MKP)-1. Therefore, the aim of this study was to address whether theophylline repressed cytokine production in a similar, PDE-dependent, MKP-1-mediated manner. Notably, theophylline did not potentiate cAMP release from ASM cells treated with the long-acting β2-agonist formoterol. Moreover, theophylline (0.1-10 μM) did not increase formoterol-induced MKP-1 messenger RNA expression nor protein up-regulation, consistent with the lack of cAMP generation. However, theophylline (at 10 μM) was antiinflammatory and repressed secretion of the neutrophil chemoattractant cytokine IL-8, which is produced in response to TNF-α. Because theophylline's effects were independent of PDE4 inhibition or antiinflammatory MKP-1, we then wished to elucidate the novel mechanisms responsible. We investigated the impact of theophylline on protein phosphatase (PP) 2A, a master controller of multiple inflammatory signaling pathways, and show that theophylline increases TNF-α-induced PP2A activity in ASM cells. Confirmatory results were obtained in A549 lung epithelial cells. PP2A activators have beneficial effects in ex vivo and in vivo models of respiratory disease. Thus, our study is the first to link theophylline with PP2A activation as a novel mechanism to control respiratory inflammation. PMID:26574643

  20. A meta-regression evaluating the effectiveness and prognostic factors of oral phosphodiesterase type 5 inhibitors for the treatment of erectile dysfunction

    Jin-Qiu Yuan

    2016-01-01

    Full Text Available The effectiveness of phosphodiesterase type 5 inhibitors (PDE5-Is for erectile dysfunction (ED varies considerably among trials, but available studies investigating the factors that affect the effectiveness are few and findings are not consistent. A systematic search was performed in PubMed, Cochrane Library, and EMBASE to identify randomized controlled trials comparing PDE5-Is with placebo for the treatment of ED. The methodological quality of included studies was assessed by the Cochrane Collaboration′s tool for assessing risk of bias. The associations between prespecified study-level factors and effectiveness were tested by a random effects meta-regression model. This study included 93 trials with 26 139 patients. When all PDE5-Is were grouped together, Caucasian ethnicity was associated with 15.636% (95% confidence interval [CI]: 0.858% to 32.579% increase in risk ratio (RR for Global Assessment Questionnaire question-1 (GAQ-1, and 1.473 (95% CI: 0.406 to 2.338 score increase in mean difference (MD for posttreatment International Index of Erectile Function-Erectile Function domain score (IIEF-EF, compared to Asian ethnicity. A one-score increase in baseline IIEF-EF was associated with −5.635% (95% CI: −9.120% to −2.017% reduction in RR for GAQ-1, and −0.229 (95% CI: −0.425 to −0.042 score decrease in MD for posttreatment IIEF-EF. In conclusion, PDE5-Is are more effective in Caucasians than Asians, and in patients with more severe ED.

  1. Angiotensin-converting enzyme inhibition prevents myocardial infarction-induced increase in renal cortical cGMP and cAMP phosphodiesterase activities.

    Clauss, François; Charloux, Anne; Piquard, François; Doutreleau, Stéphane; Talha, Samy; Zoll, Joffrey; Lugnier, Claire; Geny, Bernard

    2015-08-01

    We investigated whether myocardial infarction (MI) enhances renal phosphodiesterases (PDE) activities, investigating particularly the relative contribution of PDE1-5 isozymes in total PDE activity involved in both cGMP and cAMP pathways, and whether angiotensin-converting enzyme inhibition (ACEi) decreases such renal PDE hyperactivities. We also investigated whether ACEi might thereby improve atrial natriuretic peptide (ANP) efficiency. We studied renal cortical PDE1-5 isozyme activities in sham (SH)-operated, MI rats and in MI rats treated with perindopril (ACEi) 1 month after coronary artery ligation. Circulating atrial natriuretic peptide (ANP), its second intracellular messenger cyclic guanosine monophosphate (cGMP) and cGMP/ANP ratio were also determined. Cortical cGMP-PDE2 (80.3 vs. 65.1 pmol/min/mg) and cGMP-PDE1 (50.7 vs. 30.1 pmol/min/mg), and cAMP-PDE2 (161 vs. 104.1 pmol/min/mg) and cAMP-PDE4 (307.5 vs. 197.2 pmol/min/mg) activities were higher in MI than in SH rats. Despite increased ANP plasma level, ANP efficiency tended to be decreased in MI compared to SH rats. Perindopril restored PDE activities and tended to improve ANP efficiency in MI rats. One month after coronary ligation, perindopril treatment of MI rats prevents the increase in renal cortical PDE activities. This may contribute to increase renal ANP efficiency in MI rats. PMID:25939307

  2. Efficacy and safety of phosphodiesterase type 5 (PDE5) inhibitors in treating erectile dysfunction after bilateral nerve-sparing radical prostatectomy.

    Cui, Y; Liu, X; Shi, L; Gao, Z

    2016-02-01

    We carried out a systematic review and meta-analysis to assess the efficacy and safety of phosphodiesterase type 5 (PDE5) inhibitors for treating erectile dysfunction (ED) after bilateral nerve-sparing radical prostatectomy (BNSRP). A literature review was performed to identify all published randomised double-blind, placebo-controlled trials of PDE5 inhibitors for the treatment of ED after BNSRP. The search included the following databases: MEDLINE, EMBASE and the Cochrane Controlled Trials Register. The reference lists of the retrieved studies were also investigated. Six publications involving a total of 1678 patients were used in the analysis, including six RCTs that compared PDE5 inhibitors (tadalafil, sildenafil, avanafil and vardenafil) with placebo. Co-primary efficacy end points: International Index of Erectile Function-Erectile Function (IIEF-EF) domain score [the standardised mean difference (SMD) = 4.04, 95% confidence interval (CI) = 2.87-5.22, P < 0.00001]; successful vaginal penetration (SEP2) [the odds ratio (OR) = 14.87, 95%CI = 4.57-48.37, P < 0.00001]; and successful intercourse (SEP3) (OR = 47, 95%CI = 3-13.98, P < 0.00001) indicated that PDE5 inhibitors was more effective than the placebo. Specific adverse events with PDE5 inhibitors included headache (12.08%), dyspepsia (6.76%) and flushing (6.52%), which were significantly less likely to occur with placebo. This meta-analysis indicates that PDE5 inhibitors to be an effective and well-tolerated treatment for ED after BNSRP. PMID:25684196

  3. Phosphodiesterase 4 in inflammatory diseases: Effects of apremilast in psoriatic blood and in dermal myofibroblasts through the PDE4/CD271 complex.

    Schafer, Peter H; Truzzi, Francesca; Parton, Anastasia; Wu, Lei; Kosek, Jolanta; Zhang, Ling-Hua; Horan, Gerald; Saltari, Annalisa; Quadri, Marika; Lotti, Roberta; Marconi, Alessandra; Pincelli, Carlo

    2016-07-01

    Phosphodiesterases 4 (PDE4) act as proinflammatory enzymes via degradation of cAMP, whereas PDE4 inhibitors play an anti-inflammatory role in vitro and in vivo. In particular, apremilast has been recently approved for the treatment of psoriasis and psoriatic arthritis. However, little is known on the expression pattern of PDE4 in psoriasis. We report that PDE4B and PDE4D mRNA are overexpressed in peripheral blood mononuclear cells (PBMC) from psoriasis, as compared with normal controls, while apremilast reduces PBMC production of a number of pro-inflammatory cytokines and increases the levels of anti-inflammatory mediators. PDE4 expression is up-regulated in psoriatic dermis as compared with normal skin, with particular regard to fibroblasts. This is confirmed in vitro, where both dermal fibroblasts (DF) and, to a greater extent, myofibroblasts (DM) express all PDE4 isoforms at the mRNA and protein level. Because PDE4 interacts with the nerve growth factor (NGF) receptor CD271 in lung fibroblasts, we evaluated the relationship and function of PDE4 and CD271 in normal human skin fibroblasts. All PDE4 isoforms co-immunoprecipitate with CD271 in DM, while apremilast inhibits apoptosis induced by β-amyloid, a CD271 ligand, in DM. Furthermore, apremilast significantly reduces NGF- and transforming growth factor-β1 (TGF-β1)-induced fibroblast migration, and inhibits DF differentiation into DM mediated by NGF or TGF-β1. Finally, in DM, apremilast significantly reduces cAMP degradation induced by treatment with β-amyloid. Taken together, these results indicate that PDE4 play an important role in psoriasis. In addition, the study reveals that the PDE4/CD271 complex could be important in modulating fibroblast functions. PMID:26806620

  4. Thiazolo[3,2-a]benzimidazol-3(2H)-one derivatives: Structure-activity relationships of selective nucleotide pyrophosphatase/phosphodiesterase1 (NPP1) inhibitors.

    Lee, Sang-Yong; Perotti, Arianna; De Jonghe, Steven; Herdewijn, Piet; Hanck, Theodor; Müller, Christa E

    2016-07-15

    Ecto-nucleotide pyrophosphatase/phosphodiesterase1 (NPP1) is the most important member of the NPP family, which consists of seven closely related proteins (NPP1-NPP7). This glycoprotein is a membrane-associated or secreted enzyme, which catalyzes the hydrolysis of a wide range of phosphodiester bonds, e.g., in nucleoside triphosphates, dinucleotides and nucleotide sugars. NPP1 plays a crucial role in various physiological functions including bone mineralization, soft-tissue calcification, and insulin receptor signaling. Recently, an upregulated expression of NPP1 has been observed in astrocytic brain cancers. Therefore, NPP1 has been proposed as a novel drug target for the treatment of glioblastoma. Despite their therapeutic potential, only few NPP1 inhibitors have been reported to date, which are in most cases non- or only moderately selective. The best investigated NPP1 inhibitors so far are nucleotide derivatives and analogs, however they are not orally bioavailable due to their high polarity. We identified thiazolo[3,2-a]benzimidazol-3(2H)-one derivatives as a new class of NPP1 inhibitors with drug-like properties. Among the 25 derivatives investigated in the present study, 2-[(5-iodo-2-furanyl)methylene]thiazolo[3,2-a]benzimidazol-3(2H)-one (17) was found to be the most potent NPP1 inhibitor with a Ki value of 467nM versus ATP as a substrate and an un-competitive mechanism of inhibition. Compound 17 did not inhibit other human ecto-nucleotidases, including NTPDase1 (CD39), NTPDases2-3, NPP2, NPP3, tissue-nonspecific alkaline phosphatase (TNAP), and ecto-5'-nucleotidase (eN, CD73), and is thus highly selective for NPP1. PMID:27265686

  5. Mapping binding sites for the PDE4D5 cAMP-specific phosphodiesterase to the N- and C-domains of {beta}-arrestin using spot-immobilized peptide arrays

    Baillie, G. S.; Adams, D. R.; Bhari, N.; Houslay, T.M.; Vadrevu, S.; Meng, D.; Li, X.; Dunlop, A.; Milligan, G.; Bolger, G.B.; Klussmann, E; Houslay, M.D.

    2007-01-01

    Beta2-ARs (beta2-adrenoceptors) become desensitized rapidly upon recruitment of cytosolic beta-arrestin. PDE4D5 (family 4 cAMP-specific phosphodiesterase, subfamily D, isoform 5) can be recruited in complex with beta-arrestin, whereupon it regulates PKA (cAMP-dependent protein kinase) phosphorylation of the beta2-AR. In the present study, we have used novel technology, employing a library of overlapping peptides (25-mers) immobilized on cellulose membranes that scan the entire sequence of bet...

  6. Synthesis, docking study and relaxant effect of 2-alkyl and 2-naphthylchromones on rat aorta and guinea-pig trachea through phosphodiesterase inhibition.

    Rodríguez-Ramos, Fernando; Navarrete, Andrés; González-Andrade, Martín; Alarcón, Carlos; Aguilera-Cruz, Alejandro; Reyes-Ramírez, Adelfo

    2013-10-01

    Chromone (4), which form the base structure of various flavonoids isolated as natural products, is capable of relaxing smooth muscle. This is relevant to the treatment of high blood pressure, asthma and chronic obstructive pulmonary disease. The former disorder involves the contraction of vascular smooth muscle (VSM), and the latter two bronchoconstriction of airway smooth muscle (ASM). One of the principal mechanisms by which flavonoids relax muscle tissue is the inhibition of phosphodiesterases (PDEs), present in both VSM and ASM. Therefore, a study was designed to analyze the structure-activity relationship of chromone derivatives in vaso- and bronchorelaxation through the inhibition of PDE. Docking studies showed that these chromones bind at the catalytic site of PDEs. Consequently, we synthesized analogs of chromones substituted at position C-2 with alkyl and naphthyl groups. These compounds were synthesized from 2-hydroxyacetophenone and acyl chlorides in the presence of DBU and pyridine, modifying the methodology reported for the synthesis of 3-acylchromones by changing the reaction temperature from 80 to 30°C and using methylene chloride as solvent, yielding the corresponding phenolic esters 10a-10h. These compounds were cyclized with an equivalent of DBU, pyridine as solvent, and heated at reflux temperature, yielding the chromones 11a-11h. Evaluation of the vasorelaxant effect of 4, 11a-11h on rat aorta demonstrated that potency decreases with branched alkyl groups. Whereas the EC50 of compound 11d (substituted by an n-hexyl group) was 8.64±0.39 μM, that of 11f (substituted by an isobutyl group) was 14.58±0.64 μM. Contrarily, the effectiveness of the compound is directly proportional to the length of the alkyl chain, as evidenced by the increase in maximal effect of compound 11c versus 11d (66% versus 100%) and 11e versus 11f (60% versus 96%). With an aromatic group like naphthyl as the C-2 substituent, the effectiveness was only 43%. All compounds

  7. Treatment satisfaction among men with concurrent benign prostatic hyperplasia and erectile dysfunction treated with tadalafil or other phosphodiesterase type-5 inhibitor combinations

    Lee, Lulu K; Goren, Amir; Boytsov, Natalie N; Donatucci, Craig F; McVary, Kevin T

    2016-01-01

    Objective Erectile dysfunction (ED) and benign prostatic hyperplasia (BPH) frequently co-occur in men aged ≥40, along with lower urinary tract symptoms (LUTS) secondary to BPH. Given little real-world evidence on treatment use or satisfaction with treatment for concurrent BPH/LUTS and/or ED, this study examined medication regimens and differences in satisfaction and health-related quality of life (HRQoL) across regimens among men with concurrent BPH and ED. Methods A cross-sectional study was conducted using an Internet survey of participants recruited through an online panel. Respondents (N=736) included men (aged ≥40) who self-reported a diagnosis of both ED and BPH with prescription treatment in the past 3 months for both conditions. Treatment satisfaction (eg, convenience and ease of planning) and HRQoL (eg, International Prostate Symptom Score, sleep quality) were self-reported. Generalized linear models examined the association of regimen with treatment satisfaction and HRQoL, adjusting for covariates (eg, age and comorbidities). Results Final analyses included participants (N=507) using: tadalafil once-daily monotherapy (22%), tadalafil for ED with an alternate BPH therapy (36%), or another phosphodiesterase type-5 inhibitor (PDE5-I) combination (41%). These groups represented the major categories of treatment regimens found in the sample, excluded participants with ambiguous regimens, and were aligned with current standard of care for BPH and ED. Overall, patients reported moderate levels of BPH and a moderate-to-severe degree of ED. Tadalafil monotherapy patients had higher treatment satisfaction scores and greater reported ease of treatment planning and convenience than PDE5-I combination patients. No significant intergroup differences were found on HRQoL. Conclusion A majority of patients (59%) took tadalafil alone or in combination for BPH/ED treatment. Tadalafil monotherapy patients reported greater treatment satisfaction than patients taking PDE5

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

    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.

  9. Inhibition of Phosphodiesterase-4 (PDE4 activity triggers luminal apoptosis and AKT dephosphorylation in a 3-D colonic-crypt model

    Tsunoda Toshiyuki

    2012-07-01

    Full Text Available Abstract Background We previously established a three-dimensional (3-D colonic crypt model using HKe3 cells which are human colorectal cancer (CRC HCT116 cells with a disruption in oncogenic KRAS, and revealed the crucial roles of oncogenic KRAS both in inhibition of apoptosis and in disruption of cell polarity; however, the molecular mechanism of KRAS-induced these 3-D specific biological changes remains to be elucidated. Results Among the genes that were upregulated by oncogenic KRAS in this model, we focused on the phosphodiesterase 4B (PDE4B of which expression levels were found to be higher in clinical tumor samples from CRC patients in comparison to those from healthy control in the public datasets of gene expression analysis. PDE4B2 was specifically overexpressed among other PDE4 isoforms, and re-expression of oncogenic KRAS in HKe3 cells resulted in PDE4B overexpression. Furthermore, the inhibition of PDE4 catalytic activity using rolipram reverted the disorganization of HCT116 cells into the normal physiologic state of the epithelial cell polarity by inducing the apical assembly of ZO-1 (a tight junction marker and E-cadherin (an adherens junction marker and by increasing the activity of caspase-3 (an apoptosis marker in luminal cavities. Notably, rolipram reduced the AKT phosphorylation, which is known to be associated with the disruption of luminal cavity formation and CRC development. Similar results were also obtained using PDE4B2-shRNAs. In addition, increased expression of PDE4B mRNA was found to be correlated with relapsed CRC in a public datasets of gene expression analysis. Conclusions These results collectively suggested that PDE4B is upregulated by oncogenic KRAS, and also that the inhibition of PDE4 catalytic activity can induce both epithelial cell polarity and luminal apoptosis in CRC, thus highlighting the utility of our 3-D culture (3 DC model for the KRAS-induced development of CRC in 3-D microenvironment. Indeed

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

    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

  11. Preclinical evaluation of a promising C-11 labeled PET tracer for imaging phosphodiesterase 10A in the brain of living subject.

    Liu, Hui; Jin, Hongjun; Yue, Xuyi; Zhang, Xiang; Yang, Hao; Li, Junfeng; Flores, Hubert; Su, Yi; Perlmutter, Joel S; Tu, Zhude

    2015-11-01

    Phosphodiesterase 10A (PDE10A) plays a key role in the regulation of brain striatal signaling. A PET tracer for PDE10A may serve as a tool to evaluate PDE10A expression in vivo in central nervous system disorders with striatal pathology. Here, we further characterized the binding properties of a previously reported radioligand we developed for PDE10A, [(11)C]TZ1964B, in rodents and nonhuman primates (NHPs). The tritiated counterpart [(3)H]TZ1964B was used for in vitro binding characterizations in rat striatum homogenates and in vitro autoradiographic studies in rat brain slices. The carbon-11 labeled [(11)C]TZ1964B was utilized in the ex vivo autoradiography studies for the brain of rats and microPET imaging studies for the brain of NHPs. MicroPET scans of [(11)C]TZ1964B in NHPs were conducted at baseline, as well as with using a selective PDE10A inhibitor MP-10 for either pretreatment or displacement. The in vivo regional target occupancy (Occ) was obtained by pretreating with different doses of MP-10 (0.05-2.00 mg/kg). Both in vitro binding assays and in vitro autoradiographic studies revealed a nanomolar binding affinity of [(3)H]TZ1964B to the rat striatum. The striatal binding of [(3)H]TZ1964B and [(11)C]TZ1964B was either displaced or blocked by MP-10 in rats and NHPs. Autoradiography and microPET imaging confirmed that the specific binding of the radioligand was found in the striatum but not in the cerebellum. Blocking studies also confirmed the suitability of the cerebellum as an appropriate reference region. The binding potentials (BPND) of [(11)C]TZ1964B in the NHP striatum that were calculated using either the Logan reference model (LoganREF, 3.96 ± 0.17) or the simplified reference tissue model (SRTM, 4.64 ± 0.47), with the cerebellum as the reference region, was high and had good reproducibility. The occupancy studies indicated a MP-10 dose of 0.31 ± 0.09 mg/kg (LoganREF)/0.45 ± 0.17mg/kg (SRTM) occupies 50% striatal PDE10A binding sites. Studies

  12. Los inhibidores de las fosfodiesterasas en el tratamiento de la disfunción sexual eréctil The inhibitors of the phosphodiesterases in treatment of erectile sexual dysfunction

    Manuel Correa Jáuregui

    2010-12-01

    Full Text Available La disfunción sexual masculina impone una carga significativamente negativa en la salud, en las relaciones interpersonales, en la autoestima y en la calidad de vida de los que la padecen. Hasta finales de la década de los 80, el tratamiento se limitaba a la terapia psicosexual y a los implantes peneanos, y la causa se atribuía principalmente a factores psicológicos. El surgimiento de los inhibidores orales de fosfodiesterasa 5 con el lanzamiento del sildenafil (viagra en 1998, constituyó desde sus inicios una verdadera revolución y son ahora la primera elección del tratamiento en la disfunción eréctil, por ser bien tolerados, eficaces, no invasivos y con buenas tasas de respuesta.En el siguiente artículo se realizó una revisión del uso de los inhibidores de las fosfodiesterasas en el tratamiento de la disfunción sexual eréctil, así como las características relevantes de los medicamentos más usados en la actualidad, lo que contribuirá al conocimiento y a su mejor prescripción. Con este objetivo se consultaron los trabajos más actuales publicados en Pubmed y Medline. Los inhibidores de las fosfodiesterasa (sildenafil, vardenafil y tadalafil constituyen los medicamentos de elección en el tratamiento de la disfunción eréctil por su probada eficacia, seguridad y tolerancia.The male sexual dysfunction imposes a significantly negative burden in health, in the interpersonal relations, in self-esteem, and the quality of life of those suffering it. Up to at the end of the 80 decade, treatment was limited to psychosexual therapy and to penile implants and the cause was due to mainly to psychological factors. The appearance of oral inhibitors of phosphodiesterase-5 like the Sildenafil citrate (Viagra in1998, was from its onsets a real revolution and now are the first choice for treatment of erectile dysfunction because it is well tolerated, effective, non-invasive and with a good response rate. In present paper authors made a review

  13. Phosphodiesterases in the rat ovary

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

    2015-01-01

    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...... 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...... and PDE2A in the corpora lutea. Incubating neonatal rat ovaries with PDE4 inhibitors did not increase primordial follicle activation or change the expression of the developing follicle markers Gdf9, Amh, Inha, the proliferation marker Mki67 or the primordial follicle marker Tmeff2. In addition, the c...

  14. Application of adaptive design and decision making to a phase II trial of a phosphodiesterase inhibitor for the treatment of intermittent claudication

    Teerlink John R

    2011-05-01

    Full Text Available Abstract Background Claudication secondary to peripheral artery disease (PAD is associated with substantial functional impairment. Phosphodiesterase (PDE inhibitors have been shown to increase walking performance in these patients. K-134 is a selective PDE 3 inhibitor being developed as a potential treatment for claudication. The use of K-134, as with other PDE 3 inhibitors, in patients with PAD raises important safety and tolerability concerns, including the induction of cardiac ischemia, tachycardia, and hypotension. We describe the design, oversight, and implementation of an adaptive, phase II, dose-finding trial evaluating K-134 for the treatment of stable, intermittent claudication. Methods The study design was a double-blind, multi-dose (25 mg, 50 mg, and 100 mg of K-134, randomized trial with both placebo and active comparator arms conducted in the United States and Russia. The primary objective of the study was to compare the highest tolerable dose of K-134 versus placebo using peak walking time after 26 weeks of therapy as the primary outcome. Study visits with intensive safety assessments were included early in the study period to provide data for adaptive decision making. The trial used an adaptive, dose-finding strategy to efficiently identify the highest dose(s most likely to be safe and well tolerated, based on the side effect profiles observed within the trial, so that less promising doses could be abandoned. Protocol specified criteria for safety and tolerability endpoints were used and modeled prior to the adaptive decision making. The maximum target sample size was 85 subjects in each of the retained treatment arms. Results When 199 subjects had been randomized and 28-day data were available from 143, the Data Monitoring Committee (DMC recommended termination of the lowest dose (25 mg treatment arm. Safety evaluations performed during 14- and 28-day visits which included in-clinic dosing and assessments at peak drug

  15. Inibidores de fosfodiesterases: novas perspectivas de uma antiga terapia na asma? Phosphodiesterase inhibitors: new perspectives on an old therapy for asthma?

    Hisbello Campos

    2003-12-01

    shifted the treatment toward either prevention or the inhibition of inflammatory markers. In light of this, new drug formulations have been considered. In addition to the beta2 agonists, theophylline, and corticosteroids currently being used, the second generation of selective phosphodiesterase inhibitors has shown promising results. Recent studies suggest that these drugs may soon offer a novel alternative in the treatment of asthma.

  16. IL-1β induces hypomyelination in the periventricular white matter through inhibition of oligodendrocyte progenitor cell maturation via FYN/MEK/ERK signaling pathway in septic neonatal rats.

    Xie, Di; Shen, Fengcai; He, Shaoru; Chen, Mengmeng; Han, Qianpeng; Fang, Ming; Zeng, Hongke; Chen, Chunbo; Deng, Yiyu

    2016-04-01

    Neuroinflammation elicited by microglia plays a key role in periventricular white matter (PWM) damage (PWMD) induced by infectious exposure. This study aimed to determine if microglia-derived interleukin-1β (IL-1β) would induce hypomyelination through suppression of maturation of oligodendrocyte progenitor cells (OPCs) in the developing PWM. Sprague-Dawley rats (1-day old) were injected with lipopolysaccharide (LPS) (1 mg/kg) intraperitoneally, following which upregulated expression of IL-1β and IL-1 receptor 1 (IL-1R1 ) was observed. This was coupled with enhanced apoptosis and suppressed proliferation of OPCs in the PWM. The number of PDGFR-α and NG2-positive OPCs was significantly decreased in the PWM at 24 h and 3 days after injection of LPS, whereas it was increased at 14 days and 28 days. The protein expression of Olig1, Olig2, and Nkx2.2 was significantly reduced, and mRNA expression of Tcf4 and Axin2 was upregulated in the developing PWM after LPS injection. The expression of myelin basic protein (MBP) and 2',3'-cyclic-nucleotide 3"-phosphodiesterase (CNPase) was downregulated in the PWM at 14 days and 28 days after LPS injection; this was linked to reduction of the proportion of myelinated axons and thinner myelin sheath as revealed by electron microscopy. Primary cultured OPCs treated with IL-1β showed the failure of maturation and proliferation. Furthermore, FYN/MEK/ERK signaling pathway was involved in suppression of maturation of primary OPCs induced by IL-1β administration. Our results suggest that following LPS injection, microglia are activated and produce IL-1β in the PWM in the neonatal rats. Excess IL-1β inhibits the maturation of OPCs via suppression of FYN/MEK/ERK phosphorylation thereby leading to axonal hypomyelination. PMID:26678483

  17. Effects of experimental hypothyroidism on myelin sheath structural organization.

    Ferreira, Andréa A; Nazário, José C; Pereira, Mário J S; Azevedo, Neide L; Barradas, Penha C

    2004-03-01

    A previous study using the 2'3'cyclic nucleotide 3'phosphodiesterase (CNPase), an oligodendroglial marker that also stain ensheathed fibers, showed a decrease in the number of immunoreactive fibers and a change in the pattern of CNPase immunoreactivity (CNPase+) in hypothyroid animals. CNPase+ fibers, in mature hypothyroid animals, showed a continuous pattern of staining in contrast with a discontinuous one in controls. As CNPase, in adult animals, can be found only in regions in which oligodendrocyte cytoplasm remains as internal, external and paranodal loops, it was suggested that the reduction of thyroid hormone levels leads to a failure in myelin compaction. Previous data showed a higher frequency of some abnormalities in myelin sheath as multiple cytoplasmic loops and redundant myelin profiles in mutant animals that present a failure in myelin compaction. The increase in the frequency of these abnormalities (multiple internal and external loops and redundant myelin) indicates a failure in the interrelations between the axons and the oligodendroglial processes. To verify if the thyroid hormone deficiency during CNS development disturbs these interrelations, we evaluated the frequency of the morphological abnormalities (multiple internal and external loops and redundant myelin) in myelin sheath of corpus callosum (cc) in experimental hypothyroidism. Randomic fields were kept by electron microscopy and the analysis of the frequency of morphological abnormalities showed a significant difference in hypothyroid animals at 60-day-old (PND60), with no significant differences at 90-day-old (PND90) animals. The frequency of multiple internal loops is higher in hypothyroid animals at PND60 that indicates a disturbance in the wrapping by the oligodendroglial process. These findings showed that thyroid hormone might modulate the axon-oligodendroglial relationships that are important for the adequate temporal sequence of events that occur during myelinogenesis, with

  18. Mild intermittent hypoxemia in neonatal mice causes permanent neurofunctional deficit and white matter hypomyelination.

    Juliano, Courtney; Sosunov, Sergey; Niatsetskaya, Zoya; Isler, Joseph A; Utkina-Sosunova, Irina; Jang, Isaac; Ratner, Veniamin; Ten, Vadim

    2015-02-01

    Very low birth weight (VLBW) premature infants experience numerous, often self-limited non-bradycardic episodes of intermittent hypoxemia (IH). We hypothesized that these episodes of IH affect postnatal white matter (WM) development causing hypomyelination and neurological handicap in the absence of cellular degeneration. Based on clinical data from ten VLBW neonates; a severity, daily duration and frequency of non-bradycardic IH episodes were reproduced in neonatal mice. Changes in heart rate and cerebral blood flow during IH were recorded. A short-term and long-term neurofunctional performance, cerebral content of myelin basic protein (MBP), 2'3' cyclic-nucleotide 3-phosphodiesterase (CNPase), electron microscopy of axonal myelination and the extent of cellular degeneration were examined. Neonatal mice exposed to IH exhibited no signs of cellular degeneration, yet demonstrated significantly poorer olfactory discrimination, wire holding, beam and bridge crossing, and walking-initiation tests performance compared to controls. In adulthood, IH-mice demonstrated no alteration in navigational memory. However, sensorimotor performance on rota-rod, wire-holding and beam tests was significantly worse compared to naive littermates. Both short- and long-term neurofunctional deficits were coupled with decreased MBP, CNPase content and poorer axonal myelination compared to controls. In neonatal mice mild, non-ischemic IH stress, mimicking that in VLBW preterm infants, replicates a key phenotype of non-cystic WM injury: permanent hypomyelination and sensorimotor deficits. Because this phenotype has developed in the absence of cellular degeneration, our data suggest that cellular mechanisms of WM injury induced by mild IH differ from that of cystic periventricular leukomalacia where the loss of myelin-producing cells and axons is the major mechanism of injury. PMID:25476492

  19. CNP2 mRNA directs synthesis of both CNP1 and CNP2 polypeptides.

    O'Neill, R C; Minuk, J; Cox, M E; Braun, P E; Gravel, M

    1997-10-15

    The ribosome scanning model for translational initiation predicts that eukaryotic mRNAs should, as a rule, be monocistronic. However, cases have recently been described of eukaryotic mRNAs producing more than one protein through alternative translational initiation at several different AUG codons. The present work reports the occurrence of two translational start sites on the mRNA encoding isoform 2 of the myelin marker enzyme 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP) in rat and mouse. We show that the CNP2 mRNA is able to direct synthesis of not only CNP2, but also CNP1 polypeptide. Immunoprecipitation experiments using a polyclonal antibody directed against CNP detect both CNP isoforms in tissues or cell lines expressing only the CNP2 transcript. Thus, the synthesis of CNP1 and CNP2 polypeptides must be encoded by the CNP2 transcript. In vitro translation of synthetic CNP2 mRNA demonstrates that both CNP isoforms are synthesized by initiation at different AUG codons. Furthermore, by introducing mutations to "switch off" translation from the second in-frame AUG codon in the CNP2 cDNA, and transfecting 293T cells with those constructs, we are able to correlate the production of CNP1 and CNP2 with different translational start sites. These results lead us to conclude that the CNP2 mRNA is able to produce both CNP1 and CNP2 polypeptides. This investigation has altered our understanding of the temporal expression of the CNP protein isoforms during development of the central nervous system (CNS). PMID:9373034

  20. Resilient emotionality and molecular compensation in mice lacking the oligodendrocyte-specific gene Cnp1.

    Edgar, N M; Touma, C; Palme, R; Sibille, E

    2011-01-01

    Altered oligodendrocyte structure and function is implicated in major psychiatric illnesses, including low cell number and reduced oligodendrocyte-specific gene expression in major depressive disorder (MDD). These features are also observed in the unpredictable chronic mild stress (UCMS) rodent model of the illness, suggesting that they are consequential to environmental precipitants; however, whether oligodendrocyte changes contribute causally to low emotionality is unknown. Focusing on 2'-3'-cyclic nucleotide 3'-phosphodiesterase (Cnp1), a crucial component of axoglial communication dysregulated in the amygdala of MDD subjects and UCMS-exposed mice, we show that altered oligodendrocyte integrity can have an unexpected functional role in affect regulation. Mice lacking Cnp1 (knockout, KO) displayed decreased anxiety- and depressive-like symptoms (i.e., low emotionality) compared with wild-type animals, a phenotypic difference that increased with age (3-9 months). This phenotype was accompanied by increased motor activity, but was evident before neurodegenerative-associated motor coordination deficits (≤ 9-12 months). Notably, Cnp1(KO) mice were less vulnerable to developing a depressive-like syndrome after either UCMS or chronic corticosterone exposure. Cnp1(KO) mice also displayed reduced fear expression during extinction, despite normal amygdala c-Fos induction after acute stress, together implicating dysfunction of an amygdala-related neural network, and consistent with proposed mechanisms for stress resiliency. However, the Cnp1(KO) behavioral phenotype was also accompanied by massive upregulation of oligodendrocyte- and immune-related genes in the basolateral amygdala, suggesting an attempt at functional compensation. Together, we demonstrate that the lack of oligodendrocyte-specific Cnp1 leads to resilient emotionality. However, combined with substantial molecular changes and late-onset neurodegeneration, these results suggest the low Cnp1 seen in MDD may

  1. Chronic intermittent ethanol induced axon and myelin degeneration is attenuated by calpain inhibition.

    Samantaray, Supriti; Knaryan, Varduhi H; Patel, Kaushal S; Mulholland, Patrick J; Becker, Howard C; Banik, Naren L

    2015-10-01

    Chronic alcohol consumption causes multifaceted damage to the central nervous system (CNS), underlying mechanisms of which are gradually being unraveled. In our previous studies, activation of calpain, a calcium-activated neutral protease has been found to cause detrimental alterations in spinal motor neurons following ethanol (EtOH) exposure in vitro. However, it is not known whether calpain plays a pivotal role in chronic EtOH exposure-induced structural damage to CNS in vivo. To test the possible involvement of calpain in EtOH-associated neurodegenerative mechanisms the present investigation was conducted in a well-established mouse model of alcohol dependence - chronic intermittent EtOH (CIE) exposure and withdrawal. Our studies indicated significant loss of axonal proteins (neurofilament light and heavy, 50-60%), myelin proteins (myelin basic protein, 20-40% proteolipid protein, 25%) and enzyme (2', 3'-cyclic-nucleotide 3'-phosphodiesterase, 21-55%) following CIE in multiple regions of brain including hippocampus, corpus callosum, cerebellum, and importantly in spinal cord. These CIE-induced deleterious effects escalated after withdrawal in each CNS region tested. Increased expression and activity of calpain along with enhanced ratio of active calpain to calpastatin (sole endogenous inhibitor) was observed after withdrawal compared to EtOH exposure. Pharmacological inhibition of calpain with calpeptin (25 μg/kg) prior to each EtOH vapor inhalation significantly attenuated damage to axons and myelin as demonstrated by immuno-profiles of axonal and myelin proteins, and Luxol Fast Blue staining. Calpain inhibition significantly protected the ultrastructural integrity of axons and myelin compared to control as confirmed by electron microscopy. Together, these findings confirm CIE exposure and withdrawal induced structural alterations in axons and myelin, predominantly after withdrawal and corroborate calpain inhibition as a potential protective strategy against

  2. Modulating the Cyclic Guanosine Monophosphate Substrate Selectivity of the Phosphodiesterase 3 Inhibitors by Pyridine, Pyrido[2,3-d]pyrimidine Derivatives and Their Effects upon the Growth of HT-29 Cancer Cell Line

    Abadi, Ashraf Hassan; Hany, Marwa Saeed; Elsharif, Shimaa Awadain; Eissa, Amal Abdel Haleem; Gary, Bernard DeWayne; Tinsley, Heather Nicole; Piazza, Gary Anthony

    2016-01-01

    Analogues with the scaffolds of 3-cyano-4-alkoxyphenyl-6-bromoaryl-2-pyridone and 2-amino-3-cyano-4-alkoxyphenyl-6-bromoarylpyridine were synthesized. Cyclization of the 2-amino derivatives with formic acid and formamide gave the corresponding pyrido[2,3-d]pyrimidin-4(3H)-one and the pyrido[2,3-d]pyrimidin-4-amine derivatives, respectively. Active phosphodiesterase 3 (PDE3) inhibitors were identified from each of the four aforementioned scaffolds. This is the first report that pyrido[2,3-d]pyrimidin-4(3H)-one and pyrido[2,3-d]pyrimidin-4-amine derivatives can inhibit PDE3. The analogues with the pyridone and pyrido[2,3-d]pyrimidin-4(3H)-one scaffolds inhibited both cAMP and cyclic guanosine monophosphate (cGMP) hydrolysis by PDE3, while the amine containing scaffolds were more selective for cGMP hydrolysis. This observation may set the base for substrate-selective pharmacological modulation of this important class of drug targets and with less side effects, particularly tachcardia. The dual inhibitors of PDE3 were more potent inhibitor towards the growth of HT-29 cancer cell lines. PMID:23546000

  3. AcEST: BP912074 [AcEST

    Full Text Available .020 sp|O67622|CNPD_AQUAE 2',3'-cyclic-nucleotide 2'-phosphodiesteras... 38 0.026 sp|P25386|USO1_YEAST Intracellular protein...05 Report BLASTX 2.2.19 [Nov-02-2008] Reference: Altschul, Stephen F., Thomas L. Madden, Alejandro A. Schaffer, Jinghui Zhang, Zhen...LS3|BRE1A_CHICK E3 ubiquitin-protein ligase BRE1A OS=Gallu... 40 0.005 sp|B2A3V6|CNPD_NATTJ 2',3'-cyclic-nucleotide 2'-phosphodies...-2 heavy chain, non muscle OS=Acantha... 37 0.057 sp|A5N857|CNPD_CLOK5 2',3'-cyclic-nucleotide 2'-phosphodies...,3'-cyclic-nucleotide 2'-phosphodiesteras... 35 0.17 sp|Q01989|MYS9_DROME Myosin heavy chain 95F OS=Drosophi

  4. Phosphodiesterase MoPdeH targets MoMck1 of the conserved mitogen-activated protein (MAP) kinase signalling pathway to regulate cell wall integrity in rice blast fungus Magnaporthe oryzae.

    Yin, Ziyi; Tang, Wei; Wang, Jingzhen; Liu, Xinyu; Yang, Lina; Gao, Chuyun; Zhang, Jinlong; Zhang, Haifeng; Zheng, Xiaobo; Wang, Ping; Zhang, Zhengguang

    2016-06-01

    In the rice blast fungus Magnaporthe oryzae, the high-affinity cyclic adenosine monophosphate (cAMP) phosphodiesterase MoPdeH is important not only for cAMP signalling and pathogenicity, but also for cell wall integrity (CWI) maintenance through an unknown mechanism. By utilizing affinity purification, we found that MoPdeH interacts with MoMck1, one of the components of the mitogen-activated protein (MAP) kinase cascade that regulates CWI. Overexpression of MoMCK1 suppressed defects in autolysis and pathogenicity of the ΔMopdeH mutant, although partially, suggesting that MoPdeH plays a critical role in CWI maintenance mediated by the MAP kinase pathway. We found that MoMck1 and two other MAP kinase cascade components, MoMkk1 and MoMps1, modulate intracellular cAMP levels by regulating the expression of MoPDEH through a feedback loop. In addition, disruption of MoMKK1 resulted in less aerial hyphal formation, defective asexual development and attenuated pathogenicity. Moreover, MoMkk1 plays a role in the response to osmotic stress via regulation of MoOsm1 phosphorylation levels, whereas endoplasmic reticulum (ER) stress enhances MoMps1 phosphorylation and loss of the MAP kinase cascade component affects the unfolded protein response (UPR) pathway. Taken together, our findings demonstrate that MoPdeH functions upstream of the MoMck1-MoMkk1-MoMps1 MAP kinase pathway to regulate CWI, and that MoPdeH also mediates crosstalk between the cAMP signalling pathway, the osmotic sensing high osmolarity glycerol (HOG) pathway and the dithiothreitol (DTT)-induced UPR pathway in M. oryzae. PMID:27193947

  5. In vivo selective binding of (R)-[11C]rolipram to phosphodiesterase-4 provides the basis for studying intracellular cAMP signaling in the myocardium and other peripheral tissues

    Introduction: Phosphodiesterase-4 (PDE4) enzymes specifically break down the second messenger cAMP, thereby terminating the intracellular signaling cascade that plays an essential role in neurohormonal modulation of many physiological systems. PDE4 activity and expression are regulated by cAMP levels, suggesting that measurement of PDE4 provides an index of intracellular cAMP signaling. Methods: Male Sprague-Dawley rats were administered (R)- or the less active enantiomer (S)-[11C]rolipram and sacrificed 30 min later with tracer retention measured in various tissues. Co-injections with saturating doses of unlabeled (R)-rolipram (S)-rolipram and Ro 20-1724, as well as subtype-selective PDE inhibitors vinpocetine, Bay 60-7550, cilostazol and zaprinast were used to establish binding selectivity for PDE4 over PDE1, PDE2, PDE3 and PDE5 subtypes, respectively. Autoradiography was performed to substantiate results of biodistribution studies in the myocardium. Results: In vivo (R)-[11C]rolipram retention was dose-dependently reduced by co-injections of (R)-rolipram and (S)-rolipram (ED50 values of 0.03 mg/kg and 0.2 mg/kg, respectively). Vinpocetine, Bay 60-7550, cilostazol and zaprinast had no effect on (R)-[11C]rolipram binding, while (R)-rolipram and Ro 20-1724 reduced the tracer uptake to nonspecific levels in PDE4-rich tissues. Conclusions: In addition to the brain (R)-[11C]rolipram binds selectively to PDE4 across all cardiac regions, skeletal muscle, lungs and pancreas, but not in the adipose tissues. In vivo findings were confirmed by in vitro autoradiography studies, suggesting that (R)-[11C]rolipram can be applied to evaluate alterations in central and peripheral PDE4 levels and cAMP-mediated signaling

  6. In vivo selective binding of (R)-[{sup 11}C]rolipram to phosphodiesterase-4 provides the basis for studying intracellular cAMP signaling in the myocardium and other peripheral tissues

    Kenk, Miran [Cardiac PET Centre, Division of Cardiology, University of Ottawa Heart Institute, Ottawa, Ontario, K1Y 4W7 (Canada); Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, K1H 8M5 (Canada); Greene, Michael [Cardiac PET Centre, Division of Cardiology, University of Ottawa Heart Institute, Ottawa, Ontario, K1Y 4W7 (Canada); Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, K1H 8M5 (Canada); Thackeray, James [Cardiac PET Centre, Division of Cardiology, University of Ottawa Heart Institute, Ottawa, Ontario, K1Y 4W7 (Canada); Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, K1H 8M5 (Canada); Kemp, Robert A. de [Cardiac PET Centre, Division of Cardiology, University of Ottawa Heart Institute, Ottawa, Ontario, K1Y 4W7 (Canada); Lortie, Mireille [Cardiac PET Centre, Division of Cardiology, University of Ottawa Heart Institute, Ottawa, Ontario, K1Y 4W7 (Canada); Thorn, Stephanie [Cardiac PET Centre, Division of Cardiology, University of Ottawa Heart Institute, Ottawa, Ontario, K1Y 4W7 (Canada); Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, K1H 8M5 (Canada); Beanlands, Rob S. [Cardiac PET Centre, Division of Cardiology, University of Ottawa Heart Institute, Ottawa, Ontario, K1Y 4W7 (Canada); Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, K1H 8M5 (Canada); DaSilva, Jean N. [Cardiac PET Centre, Division of Cardiology, University of Ottawa Heart Institute, Ottawa, Ontario, K1Y 4W7 (Canada) and Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, K1H 8M5 (Canada)]. E-mail: jdasilva@ottawaheart.ca

    2007-01-15

    Introduction: Phosphodiesterase-4 (PDE4) enzymes specifically break down the second messenger cAMP, thereby terminating the intracellular signaling cascade that plays an essential role in neurohormonal modulation of many physiological systems. PDE4 activity and expression are regulated by cAMP levels, suggesting that measurement of PDE4 provides an index of intracellular cAMP signaling. Methods: Male Sprague-Dawley rats were administered (R)- or the less active enantiomer (S)-[{sup 11}C]rolipram and sacrificed 30 min later with tracer retention measured in various tissues. Co-injections with saturating doses of unlabeled (R)-rolipram (S)-rolipram and Ro 20-1724, as well as subtype-selective PDE inhibitors vinpocetine, Bay 60-7550, cilostazol and zaprinast were used to establish binding selectivity for PDE4 over PDE1, PDE2, PDE3 and PDE5 subtypes, respectively. Autoradiography was performed to substantiate results of biodistribution studies in the myocardium. Results: In vivo (R)-[{sup 11}C]rolipram retention was dose-dependently reduced by co-injections of (R)-rolipram and (S)-rolipram (ED{sub 50} values of 0.03 mg/kg and 0.2 mg/kg, respectively). Vinpocetine, Bay 60-7550, cilostazol and zaprinast had no effect on (R)-[{sup 11}C]rolipram binding, while (R)-rolipram and Ro 20-1724 reduced the tracer uptake to nonspecific levels in PDE4-rich tissues. Conclusions: In addition to the brain (R)-[{sup 11}C]rolipram binds selectively to PDE4 across all cardiac regions, skeletal muscle, lungs and pancreas, but not in the adipose tissues. In vivo findings were confirmed by in vitro autoradiography studies, suggesting that (R)-[{sup 11}C]rolipram can be applied to evaluate alterations in central and peripheral PDE4 levels and cAMP-mediated signaling.

  7. Proof-of-Concept Randomized Controlled Study of Cognition Effects of the Proprietary Extract Sceletium tortuosum (Zembrin Targeting Phosphodiesterase-4 in Cognitively Healthy Subjects: Implications for Alzheimer’s Dementia

    Simon Chiu

    2014-01-01

    Full Text Available Introduction. Converging evidence suggests that PDE-4 (phosphodiesterase subtype 4 plays a crucial role in regulating cognition via the PDE-4-cAMP cascade signaling involving phosphorylated cAMP response element binding protein (CREB. Objective. The primary endpoint was to examine the neurocognitive effects of extract Sceletium tortuosum (Zembrin and to assess the safety and tolerability of Zembrin in cognitively healthy control subjects. Method. We chose the randomized double-blind placebo-controlled cross-over design in our study. We randomized normal healthy subjects (total n=21 to receive either 25 mg capsule Zembrin or placebo capsule once daily for 3 weeks, in a randomized placebo-controlled 3-week cross-over design. We administered battery of neuropsychological tests: CNS Vital Signs and Hamilton depression rating scale (HAM-D at baseline and regular intervals and monitored side effects with treatment emergent adverse events scale. Results. 21 subjects (mean age: 54.6 years ± 6.0 yrs; male/female ratio: 9/12 entered the study. Zembrin at 25 mg daily dosage significantly improved cognitive set flexibility (P<0.032 and executive function (P<0.022, compared with the placebo group. Positive changes in mood and sleep were found. Zembrin was well tolerated. Conclusion. The promising cognitive enhancing effects of Zembrin likely implicate the PDE-4-cAMP-CREB cascade, a novel drug target in the potential treatment of early Alzheimer’s dementia. This trial is registered with ClinicalTrials.gov NCT01805518.

  8. Application of a high resolution benchtop quadrupole-Orbitrap mass spectrometry for the rapid screening, confirmation and quantification of illegal adulterated phosphodiesterase-5 inhibitors in herbal medicines and dietary supplements.

    Shi, Feng; Guo, Changchuan; Gong, Liping; Li, Jun; Dong, Peng; Zhang, Jinling; Cui, Ping; Jiang, Shuyin; Zhao, Yanxia; Zeng, Su

    2014-05-30

    In this study, the applicability of high resolution quadrupole-Orbitrap (Q-Orbitrap) mass spectrometry for the simultaneous qualitative and quantitative analysis of illegal adulterated phosphodiesterase-5 inhibitors (PDE-5 inhibitors) in herbal medicines and dietary supplements was investigated. The mass spectrometer was operated in full MS scan/dd-MS(2) (data-dependent MS(2)) mode. The use of 70,000 FWHM mass resolution and narrow mass windows (5 ppm) could effectively improve the selectivity of the method, increasing the signal-to-noise ratio for the analytes. The response showed good linear relationship with the analytes' concentrations over wide ranges (e.g., 0.05-10 μg/g for sildenafil) with all the coefficient of determinations (r(2)) >0.9996. The detection limits (LODs) were in the range of 1.0-5.0 ng/g for different analytes. The recoveries ranged from 85.4% to 96.7%. The intra- and inter-day accuracies were in the range of -6.6 to 10.1%, while the intra- and inter-day precision ranged from 0.0039% to 13.2%. Among 68 batches of herbal medicines and 20 batches of dietary supplements (including 83 capsules, 3 pellets and 2 liquid) samples, sildenafil was detected in 8 dietary supplements, while noracetildenafil was detected in only one dietary supplement. The novel Q-Orbitrap mass spectrometry has been proved to be a very promising and powerful tool for routine screening of illegal adulterate in herbal medicines and dietary supplements, ensuring food safety and public health. PMID:24377735

  9. Study design and rationale for investigating phosphodiesterase type 5 inhibition for the treatment of pulmonary hypertension due to chronic obstructive lung disease: the TADA-PHiLD (TADAlafil for Pulmonary Hypertension associated with chronic obstructive Lung Disease) trial.

    Maron, Bradley A; Goldstein, Ronald H; Rounds, Sharon I; Shapiro, Shelley; Jankowich, Matthew; Garshick, Eric; Moy, Marilyn L; Gagnon, David; Choudhary, Gaurav

    2013-12-01

    In patients with chronic obstructive pulmonary disease (COPD), moderate or severe pulmonary hypertension (COPD-PH) is associated with increased rates of morbidity and mortality. Despite this, approaches to treatment and the efficacy of phosphodiesterase type 5 inhibition (PDE-5i) in COPD-PH are unresolved. We present the clinical rationale and study design to assess the effect of oral tadalafil on exercise capacity, cardiopulmonary hemodynamics, and clinical outcome measures in COPD-PH patients. Male and female patients 40-85 years old with GOLD stage 2 COPD or higher and pulmonary hypertension diagnosed on the basis of invasive cardiac hemodynamic assessment (mean pulmonary artery pressure [mPAP] >30 mmHg, pulmonary vascular resistance [PVR] >2.5 Wood units, and pulmonary capillary wedge pressure ≤18 mmHg at rest) will be randomized at a 1∶1 ratio to receive placebo or oral PDE-5i with tadalafil (40 mg daily for 12 months). The primary end point is change from baseline in 6-minute walk distance at 12 months. The secondary end points are change from baseline in PVR and mPAP at 6 months and change from baseline in peak volume of oxygen consumption ([Formula: see text]) during exercise at 12 months. Changes in systemic blood pressure and/or oxyhemoglobin saturation (Sao2) at rest and during exercise will function as safety outcome measures. TADA-PHiLD (TADAlafil for Pulmonary Hypertension assocIated with chronic obstructive Lung Disease) is the first sufficiently powered randomized clinical trial testing the effect of PDE-5i on key clinical and drug safety outcome measures in patients with at least moderate PH due to COPD. PMID:25006405

  10. Molecular structure of the dihydropyridazinone cardiotonic 1,3-dihydro-3,3-dimethyl-5-(1,4,5,6-tetrahydro-6-oxo-pyridazinyl)- 2H-indol-2-one, a potent inhibitor of cyclic AMP phosphodiesterase.

    Robertson, D W; Jones, N D; Krushinski, J H; Pollock, G D; Swartzendruber, J K; Hayes, J S

    1987-04-01

    The cardiotonic 1,3-dihydro-3,3-dimethyl-5-(1,4,5,6-tetrahydro-6-oxo-3- pyridazinyl)-2H-indol-2-one (1, LY195115) is a potent, competitive inhibitor (Ki = 80 nM) of sarcoplasmic reticulum derived phosphodiesterase (SR-PDE). Moreover, the compound is a potent positive inotrope both in vitro and in vivo. To assist further cardiotonic drug-design studies, we have mapped the three-dimensional structure of 1 using X-ray crystallography. From a global viewpoint, this drug was essentially planar, but two small regions of nonplanarity were apparent. These involved the geminal methyl substituents in the indol-2-one moiety and the C5' methylene unit of the dihydropyridazinone ring. Because of our previous studies involving the bipyridine cardiotonics amrinone and milrinone, the conformational relationship between the plane of the phenyl ring and the horizontal symmetry plane defined by N2', C3', and C4' of 1 was of particular interest. The C6-C5-C3'-C4' dihedral angle was -2.7 degrees, whereas the C6-C5-C3'-N2' dihedral angle was 174.6 degrees. Therefore the two rings maintain a high degree of coplanarity. Compound 4, the congener of 1 possessing a completely unsaturated pyridazinone ring was also studied. In terms of inotropic activity, this compound, devoid of any puckering in the pyridazinone moiety, was equipotent with 1. Methyl substitution at the 4-position of the dihydropyridazinone and pyridazinone rings provided disparate results. Compound 2, the 4-methyl analogue of 1, was 2-fold more potent than 1, and the methyl substituent probably caused only minor perturbations in overall molecular topology. However 5, the 4-methyl analogue of the pyridazinone 4, was 4.4-fold less active than 4, perhaps as a result of methyl-induced molecular nonplanarity. PMID:3031290

  11. Protective effects of BAY 73-6691, a selective inhibitor of phosphodiesterase 9, on amyloid-β peptides-induced oxidative stress in in-vivo and in-vitro models of Alzheimer's disease.

    Li, Jian; Liu, Chun-Na; Wei, Ning; Li, Xi-Dong; Liu, Yuan-Yuan; Yang, Rui; Jia, Yu-Jie

    2016-07-01

    Alzheimer's disease (AD) is accompanied by enhanced oxidative stress and excess free radicals. Phosphodiesterase 9 inhibitors (PDE-9Is) showed memory improving effects in many pharmacological deficit models. However, whether BAY 73-6691 (a selective PDE-9I) may attenuate the oxidative stress during the development of AD is still unclear. For this purpose, primary cultures of SH-SY5Y cells were incubated with 20μM beta-amyloid25-35 (Aβ25-35), followed by exposure to different concentrations (50, 100, 150 and 200μg/ml) of BAY 73-6691. Furthermore, the antioxidant effect of BAY 73-6691 was evaluated in mice subjected to intracerebroventricular injection of Aβ25-35 (day 0) and treatment with BAY 73-6691 by intraperitoneal injection once daily (days 1-10). Our results elucidated that treatment with BAY 73-6691 attenuated the Aβ25-35-induced cytotoxicity and oxidative stress in SH-SY5Y cells. In vivo, BAY 73-6691 protected Aβ25-35-induced oxidative damage in hippocampus, associated with the attenuation of impairments in hippocampal neurons. Administration of BAY 73-6691 improved learning and memory in the Morris water maze test, and restored several hippocampal memory-associated proteins. Our study identified a neuroprotective role for BAY 73-6691 against Aβ25-35-induced oxidative stress in vivo and in vitro, harboring therapeutic potential for the treatment of AD by alleviating the impairments in spatial memory and hippocampal neurons. PMID:27071547

  12. High-performance liquid chromatography with diode array detection method for the simultaneous determination of seven selected phosphodiesterase-5 inhibitors and serotonin reuptake inhibitors used as male sexual enhancers.

    Baker, Mostafa M; Belal, Tarek S; Mahrous, Mohamed S; Ahmed, Hytham M; Daabees, Hoda G

    2016-05-01

    This work presents a simple, sensitive and generic high-performance liquid chromatography with diode array detection method for the simultaneous determination of seven drugs prescribed for the treatment of erectile dysfunction and premature ejaculation. Investigated drugs include the phosphodiesterase-5 inhibitors: sildenafil, tadalafil, and vardenafil, in addition to the selective serotonin reuptake inhibitors: dapoxetine, duloxetine, fluoxetine, and paroxetine. The drugs were separated using a Waters C8 column (4.6 × 250 mm, 5 μm) with the mobile phase consisting of phosphate buffer pH 3, acetonitrile and methanol in the ratio 60:33:7. The flow rate was 1.2 mL/min, and quantification was based on measuring peak areas at 225 nm. Peaks were perfectly resolved with retention times 3.3, 3.9, 6.4, 7.5, 9.5, 10.7, and 13.4 min for vardenafil, sildenafil, paroxetine, duloxetine, dapoxetine, fluoxetine, and tadalafil, respectively. The developed method was validated with respect to system suitability, linearity, ranges, accuracy, precision, robustness, and limits of detection and quantification. The proposed method showed good linearity in the ranges 5-500, 2-200, 2-200, 3-300, 1.5-150, 2-200, and 2-200 μg/mL for sildenafil, tadalafil, vardenafil, dapoxetine, duloxetine fluoxetine, and paroxetine, respectively. The limits of detection were 0.18-0.38 μg/mL for the analyzed compounds. The applicability of the proposed method to real life situations was assessed through the analysis of commercial tablets, and satisfactory results were obtained. PMID:26970347

  13. The phosphodiesterase 4 inhibitor roflumilast augments the Th17-promoting capability of dendritic cells by enhancing IL-23 production, and impairs their T cell stimulatory activity due to elevated IL-10.

    Bros, Matthias; Montermann, Evelyn; Cholaszczyńska, Anna; Reske-Kunz, Angelika B

    2016-06-01

    Phosphodiesterase 4 (PDE4) inhibitors serve to prevent degradation of the intracellular second messenger cAMP, resulting in broad anti-inflammatory effects on different cell types including immune cells. Agents that elevate cAMP levels via activation of adenylate cyclase have been shown to imprint a Th17-promoting capacity in dendritic cells (DCs). Therefore, we studied the potential of therapeutically relevant PDE inhibitors to induce a pronounced Th17-skewing capacity in DCs. Here we show that mouse bone marrow-derived (BM-) DCs when treated with the PDE4 inhibitor roflumilast (ROF, trade name: Daxas) in the course of stimulation with LPS (ROF-DCs) evoked elevated IL-17 levels in cocultured allogeneic T cells. In addition, as compared with control settings, levels of IFN-γ remained unaltered, while contents of Th2 cytokines (IL-5, IL-10) were diminished. ROF enhanced expression of the Th17-promoting factor IL-23 in BM-DCs. In line, neutralizing antibodies specific for IL-23 or IL-6 when applied to DC/T cell cocultures partially inhibited the IL17-promoting effect of ROF-DCs. Furthermore, ROF-DCs displayed a markedly diminished allogeneic T cell stimulatory capacity due to enhanced production of IL-10, which was restored upon application of IL-10 specific neutralizing antibody to DC/T cell cocultures. Both the IL-17-inducing and impaired T cell stimulatory capacity of BM-DCs were mimicked by a specific activator of protein kinase A, while stimulation of EPACs (exchange proteins of activated cAMP) did not yield such effects. Taken together, our findings suggest that PDE4 inhibitors aside from their broad overall anti-inflammatory effects may enhance the Th17-polarizing capacity in DCs as an unwanted side effect. PMID:27070502

  14. N-Glycomic and Microscopic Subcellular Localization Analyses of NPP1, 2 and 6 Strongly Indicate that trans-Golgi Compartments Participate in the Golgi to Plastid Traffic of Nucleotide Pyrophosphatase/Phosphodiesterases in Rice.

    Kaneko, Kentaro; Takamatsu, Takeshi; Inomata, Takuya; Oikawa, Kazusato; Itoh, Kimiko; Hirose, Kazuko; Amano, Maho; Nishimura, Shin-Ichiro; Toyooka, Kiminori; Matsuoka, Ken; Pozueta-Romero, Javier; Mitsui, Toshiaki

    2016-08-01

    Nucleotide pyrophosphatase/phosphodiesterases (NPPs) are widely distributed N-glycosylated enzymes that catalyze the hydrolytic breakdown of numerous nucleotides and nucleotide sugars. In many plant species, NPPs are encoded by a small multigene family, which in rice are referred to NPP1-NPP6 Although recent investigations showed that N-glycosylated NPP1 is transported from the endoplasmic reticulum (ER)-Golgi system to the chloroplast through the secretory pathway in rice cells, information on N-glycan composition and subcellular localization of other NPPs is still lacking. Computer-assisted analyses of the amino acid sequences deduced from different Oryza sativa NPP-encoding cDNAs predicted all NPPs to be secretory glycoproteins. Confocal fluorescence microscopy observation of cells expressing NPP2 and NPP6 fused with green fluorescent protein (GFP) revealed that NPP2 and NPP6 are plastidial proteins. Plastid targeting of NPP2-GFP and NPP6-GFP was prevented by brefeldin A and by the expression of ARF1(Q71L), a dominant negative mutant of ADP-ribosylation factor 1 that arrests the ER to Golgi traffic, indicating that NPP2 and NPP6 are transported from the ER-Golgi to the plastidial compartment. Confocal laser scanning microscopy and high-pressure frozen/freeze-substituted electron microscopy analyses of transgenic rice cells ectopically expressing the trans-Golgi marker sialyltransferase fused with GFP showed the occurrence of contact of Golgi-derived membrane vesicles with cargo and subsequent absorption into plastids. Sensitive and high-throughput glycoblotting/mass spectrometric analyses showed that complex-type and paucimannosidic-type glycans with fucose and xylose residues occupy approximately 80% of total glycans of NPP1, NPP2 and NPP6. The overall data strongly indicate that the trans-Golgi compartments participate in the Golgi to plastid trafficking and targeting mechanism of NPPs. PMID:27335351

  15. Mapping binding sites for the PDE4D5 cAMP-specific phosphodiesterase to the N- and C-domains of beta-arrestin using spot-immobilized peptide arrays.

    Baillie, George S; Adams, David R; Bhari, Narinder; Houslay, Thomas M; Vadrevu, Suryakiran; Meng, Dong; Li, Xiang; Dunlop, Allan; Milligan, Graeme; Bolger, Graeme B; Klussmann, Enno; Houslay, Miles D

    2007-05-15

    Beta2-ARs (beta2-adrenoceptors) become desensitized rapidly upon recruitment of cytosolic beta-arrestin. PDE4D5 (family 4 cAMP-specific phosphodiesterase, subfamily D, isoform 5) can be recruited in complex with beta-arrestin, whereupon it regulates PKA (cAMP-dependent protein kinase) phosphorylation of the beta2-AR. In the present study, we have used novel technology, employing a library of overlapping peptides (25-mers) immobilized on cellulose membranes that scan the entire sequence of beta-arrestin 2, to define the interaction sites on beta-arrestin 2 for binding of PDE4D5 and the cognate long isoform, PDE4D3. We have identified a binding site in the beta-arrestin 2 N-domain for the common PDE4D catalytic unit and two regions in the beta-arrestin 2 C-domain that confer specificity for PDE4D5 binding. Alanine-scanning peptide array analysis of the N-domain binding region identified severely reduced interaction with PDE4D5 upon R26A substitution, and reduced interaction upon either K18A or T20A substitution. Similar analysis of the beta-arrestin 2 C-domain identified Arg286 and Asp291, together with the Leu215-His220 region, as being important for binding PDE4D5, but not PDE4D3. Transfection with wild-type beta-arrestin 2 profoundly decreased isoprenaline-stimulated PKA phosphorylation of the beta2-AR in MEFs (mouse embryo fibroblasts) lacking both beta-arrestin 1 and beta-arrestin 2. This effect was negated using either the R26A or the R286A mutant form of beta-arrestin 2 or a mutant with substitution of an alanine cassette for Leu215-His220, which showed little or no PDE4D5 binding, but was still recruited to the beta2-AR upon isoprenaline challenge. These data show that the interaction of PDE4D5 with both the N- and C-domains of beta-arrestin 2 are essential for beta2-AR regulation. PMID:17288540

  16. 磷酸二酯酶参与认知与情绪调节的研究进展%Progress in the role of phosphodiesterases in memory regulation

    陈玲; 徐英; 潘建春

    2012-01-01

    磷酸二酯酶(PDE)催化水解cAMP和cGMP,是细胞内降解cAMP和cGMP的唯一途径.PDE是一个多基因大家族酶,包含11型不同家族,它们的结构,分布以及调节方式对抑制剂的敏感性都不同.PDE选择性抑制剂可通过抑制cAMP或cGMP水解来调节学习记忆障碍等中枢神经系统疾病.因此,PDE被认为在中枢神经系统疾病的治疗上具有重要地位.本综述介绍目前PDE参与学习记忆障碍这一中枢神经系统疾病调节的研究进展,而且PDE作为中枢神经系统疾病的治疗靶点,研究其选择性抑制剂具有重要的意义.%Phosphodiesterases (PDEs) are a super-family of enzymes that are involved in the regulation of the intracellular second messengers cAMP and cGMP by controlling their rates of hydrolysis. There are 11 different PDE families, and each family has typically multiple isof'orms and splice variants. The PDEs differ in their structures , distribution, modes of regulation, and sensitivity to inhibitors. Since PDEs have been demonstrated to play distinct roles in the process of emotion, and related learning and memory, selective PDE inhibitors, by preventing the breakdown of cAMP and/or cGMP, could modulate mood and related cognitive activity. This review discusses the current status and future development in the burgeoning field of PDEs in the central nervous system. It is becoming increasingly clear that PDE inhibitors have therapeutic potential for the treatment of neuropsychiatric disorders involving disturbances of mood, emotion, and cognition.

  17. Effects of olfactory ensheathing cells on the proliferation and differentiation of neural stem cells

    Xuewei Xie; Zhouping Tang; Feng Xu; Na Liu; Zaiwang Li; Suiqiang Zhu; Wei Wang

    2009-01-01

    BACKGROUND: Olfactory ensheathing cells can promote oriented differentiation and proliferation of neural stem cells by cell-secreted neural factors.OBJECTIVE: To observe the effect of olfactory ensheathing cells on the differentiation and proliferation of neural stem cells.DESIGN, TIME AND SETrlNG: Cytology was performed at the Department of Neurology, Tongji Medical College, Huazhong University of Science and Technology, China, from September 2007 to October 2008.MATERIALS: Mouse anti-nestin polyclonal antibody (Chemicon, USA), mouse anti-glial fibrillary acidic protein (GFAP) IgG1, mouse anti-2', 3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) IgG1, mouse anti-Tubulin Class-Ill IgG1 (Neo Markers, USA), Avidin-labeled Cy3 (KPL, USA), and goat anti-mouse IgG1: fluorescein isothiocyanate (FITC) (Serotec, UK) were used in this study.METHODS: Tissues were isolated from the embryonic olfactory bulb and subependymal region of Wistar rats. Serum-free DMEM/F12 culture media was used for co-culture experiments. Neural stem cells were incubated in serum-free or 5% fetal bovine serum-containing DMEM/F12 as controls.MAIN OUTCOME MEASURES: After 7 days of co-culture, neural stem cells and olfactory ensheathing cells underwent immunofluorescent staining for nestin, tubulin, glial fibrillary acidic protein, and CNPase.RESULTS: Olfactory ensheathing cells promoted proliferation and differentiation of neural stem cells into neuron-like cells, astrocytes and oligodendrocytes. The proportion of neuron-like cells was 78.2%, but the proportion of neurons in 5% fetal bovine serum DMEM/F12 was 48.3%. In the serum-free DMEM/F12, neural stem cells contracted, unevenly adhered to the glassware wall, or underwent apoptosis at 7 days.CONCLUSION: Olfactory ensheathing cells promote differentiation of neural stem cells mainly into neuron-like cells, and accelerate proliferation of neural stem cells. The outcome is better compared with serum-free medium or medium containing 5% fetal bovine

  18. 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

    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.

  19. Use of a column-switching high-performance liquid chromatography method to assess the presence of specific binding of (R)- and (S)-[11C]rolipram and their labeled metabolites to the phosphodiesterase-4 enzyme in rat plasma and tissues

    Introduction: To complement recent studies using the high-affinity 11C-labeled phosphodiesterase-4 (PDE4) inhibitor (R)-rolipram and the less active enantiomer (S)-[11C]rolipram for in vivo quantification of PDE4 levels, we evaluated the presence of radiolabeled metabolites and their potential binding to PDE4 in the rat plasma, brain, heart, pancreas, skeletal muscle and brown adipose tissue. Methods: A reverse-phase capture and analytical HPLC column-switch method was used to detect (R)-[11C]rolipram, (S)-[11C]rolipram and their radiolabeled metabolites in rat plasma and tissue extracts. The relative proportion of PDE4-specific binding of the radiotracers and their labeled metabolites was analyzed following co-injections with a saturating dose of unlabeled (R)-rolipram at 45 min post-tracer injection in tissue extracts. Results: Radiolabeled metabolites were found in the plasma (72-75% of total radioactive signal), and in the heart, skeletal muscle, pancreas and brown adipose tissue (44-52%), but not in the brain. In comparison to polar labeled metabolites, the proportion of unchanged (R)-[11C]rolipram was reduced in PDE4-rich organs by co-injection of unlabeled (R)-rolipram. Conversely, no changes were obtained in brown adipose tissue, or with (S)-[11C]rolipram, suggesting that radiolabeled metabolites of (R)-[11C]rolipram display no specific binding to PDE4. Conclusions: Radiolabeled hydrophilic metabolites are unlikely to compete with (R)-[11C]rolipram for PDE4-specific retention. However, due to the high proportion of the radioactive metabolites in the total radioactive signal, any kinetic modeling calculations in the peripheral tissues will need to take into account the presence of labeled metabolites

  20. Contribuição na prevenção da isquemia cerebral pelo cilostazol, um inibidor da fosfodiesterase III: revisão de literatura Contribution to prevention of cerebral ischemia by cilostazol, a phosphodiesterase III inhibitor: a review

    Marcelo Pereira da Rosa

    2008-03-01

    Full Text Available Esta revisão bibliográfica objetiva expor estas pesquisas sobre as ações do cilostazol no sistema nervoso central. O cilostazol é uma droga que demonstrou exercer inibição seletiva e potente da fosfodiesterase tipo III, ocasionando o aumento de adenosina cíclica -3',5'-monofosfato nas plaquetas, nas células endoteliais e nas células musculares lisas, sendo classificado como vasodilatador, antiagregante plaquetário e antitrombótico. É o fármaco de primeira escolha na claudicação intermitente devido à doença arterial obstrutiva periférica. Além disso, há evidências de que o cilostazol é eficaz no processo aterosclerótico cerebral, promovendo aumento do fluxo e volume sangüíneos e prevenindo infartos, especialmente lacunares e recorrentes, por diminuir a morte celular devido à apoptose e ao estresse oxidativo nas substâncias branca e parda.This literature review aims at presenting the main possibilities for the clinical application of cilostazol in the central nervous system. Cilostazol, a selective phosphodiesterase type III inhibitor, increases adenosine 3',5'-cyclic monophosphate levels on platelets, endothelial and smooth muscle cells, having vasodilatory, antiplatelet and antithrombotic properties. Currently, it is the first-choice drug for intermittent claudication, due to peripheral occlusive vascular disease. In addition, there is evidence showing that cilostazol is efficacious in cerebral atherosclerotic process, resulting in increase of blood flow and volume and preventing infarctions, especially lacunar and recurrent, since it reduces cellular death due to apoptosis and oxidative stress in white and gray substances.

  1. Lon-exchange high-performance liquid chromatography analysis of rabbit liver cyclic nucleotide phosphodiesterase reaction mixture%离子交换高效液相色谱法分析兔肝环核苷酸磷酸二酯酶反应体系

    廖飞; 张晓萍; 周岐新; 杨俊清; 曾昭淳; 陈文缘; 汤先觉

    2001-01-01

    目的:用阴离子交换HPLC分析环核苷酸磷酸二酯酶反应体系。方法:用Shim-Pak WAX-I柱,30 mmol/L的pH 4.0磷酸钾为流动相,洗脱速度0.5 ml/min,254 nm检测,峰面积定量。结果:上述离子交换HPLC体系可分离并定量测定cAMP和AMP。在硫酸铵分级粗制兔肝PDE反应混合物中,cAMP和AMP同杂质完全基线分离;随反应进行,cAMP逐步下降,AMP上升到平台后再下降。用米氏酶的积分速度方程作图分析cAMP下降的进程曲线,发现硫酸铵分级粗制的兔肝PDE的米氏常数为负数。结论:此离子交换HPLC方法可以分析无杂酶干扰时PDE对cAMP的水解。%Objective: Ion-exchange high-performance liquid chromatography (HPLC) was investigated for the analysis of cAMP hydrolysis catalyzed by rabbit liver cyclic nucleotide phosphodiesterase (PDE). Methods: The HPLC column was Shim-Pak WAX-1, mobile phase was 30 mmoI/L potassium phosphate at pH 4.0 eluted at 0.5ml/min, detection was absorbance at 254 nm, and quantification was performed with peak area. Results: cAMP and AMP were well-resolved and quantified by peak area under this HPLC condition. Rabbit liver PDE was partially purified by ammonium sulfate fractionation. In this PDE reaction mixture, residual contaminants after extraction were all baseline-resolved from both cAMP and AMP. The time course of rabbit PDE reaction showed that cAMP continuously dropped but AMP increased to a plateau before dropping. Analysis of cAMP dropping by the integrated Michaels-Menten rate equation of mono-substrate irreversible reaction lead to negative Michaelis constant. Conclusion: This ion-exchange HPLC method was desirable for the analysis of cAMP hydrolysis by PDE without phosphatase interference.

  2. Phosphodiesterase type 5 inhibitors: back and forward from cardiac indications

    Corinaldesi, C.; Di Luigi, L.; A.Lenzi; Crescioli, C.

    2015-01-01

    PDE5 inhibitors (PDE5i) are widely known as treatment for erectile dysfunction (ED). This favorable action has emerged as a “side effect” from pioneering studies when PDE5i have been originally proposed as treatment for coronary artery disease (CAD). PDE5i showed marginal benefits for CAD treatment; although disappointing for that indication, they improved systemic and pulmonary vasodilation and ameliorated general endothelial function. Therefore, PDE5i have been approved and licensed also fo...

  3. Pharmacophore elucidation and molecular docking studies on phosphodiesterase-5 inhibitors

    Radwan, Awwad Abdoh

    2015-01-01

    cGMP-binding cGMP-specific PDE, PDE5 plays a key role in the hydrolysis of cyclic guanidine monophosphate. Because cGMP mediates vascular functions, a PDE5 inhibitor that elevates cGMP level is an attractive means for vasodilatation and treatment of erectile dysfunction. In this paper we report the elucidation of the common pharmacophore hypothesis of different classes of PDE5 inhibitors. Using LigandScout program, pharmacophore modelling studies were performed on prior reported potent PDE5 i...

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

    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.......0061, P=2.89×10(-5)). In summary, these results show that genomic instability and cellular senescence in VSMCs increase PDE1 expression. This might play a role in aging-related loss of vasodilator function, VSMC senescence, increased blood pressure and vascular hypertrophy....

  5. 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

    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

  6. 磷酸二酯酶3型抑制剂西洛他唑对TNF-α诱导人脐静脉内皮细胞释放可溶性粘附分子的影响%Effects of a phosphodiesterase 3 inhibitor, cilostazol on soluble adhesion molecules release from TNF-α-stimulated human umbilical endothelial cells

    罗景慧; 林永成; 陈志良; 渡边裕司; 尾関真理子; 林秀晴

    2003-01-01

    To examine the effects of cilostazol, a novel selective phosphodiesterase type 3 inhibitor, on soluble cell adhesion molecules (sCAMs) released from tumor necrosis factor-α (TNF-α)-stimulated human umbilical endothelial cells (HUVECs), and to investigate the possible mechanisms of these effects of cilostazol. METHODS: Confluent HUVECs between 4-6 passages were used and stimulated by TNF-α (10 μg*L-1) with or without coincubation of cilostazol (1-10 μmol*L-1) for 24 h. Soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intercellular adhesion molecule-1 (sICAM-1) and soluble endothelial leukocyte adhesion molecule-1 (sELAM-1, sE-selectin) in cell culture medium were measured by ELISA, and availability of cells was detected by MTT assay. RESULTS: Cilostazol (1-10 μmol*L-1) did not affect sICAM-1 and sE-selectin released from HUVECs, but in contrast, it significantly inhibited the production of TNF-α-induced sVCAM-1, and this effect was canceled by Lω-nitro-L-arginine methyl ester (Lω-NAME, 0.1 μmol*L-1), a nonselective nitro oxide synthase (NOS) inhibitor. MTT assay indicated that the treatment of HUVECs with cilostazol (1-30 μmol*L-1) for 24 h affected cell availability in a complex pattern. It was increased at a low dose of cilostazol (1 μmol*L-1), but it was decreased at a relatively high dosage, 30 μmol*L-1. And at the medium dosage of cilostazol, 10 μmol*L-1, cell availability was almost unaffected. CONCLUSIONS: Cilostazol significantly inhibits sVCAM-1 released from TNF-α-activated HUVECs, and the effect on cytokine-challenged endothelial cells might have some relationship with activating NOS, and possibly, it is via a NO-dependent pathway. The present result suggests that cilostazol partially eliminates some of the adherent reactions of HUVECs to TNF-α, a deleterious cytokine, and to some extent, it might have the potential to prevent atherosclerosis and other cardiovascular diseases.%目的:研究新型磷酸二酯酶3型抑制剂西

  7. Histopathologic characterization of the BTBR mouse model of autistic-like behavior reveals selective changes in neurodevelopmental proteins and adult hippocampal neurogenesis

    Stephenson Diane T

    2011-05-01

    Full Text Available Abstract Background The inbred mouse strain BTBR T+ tf/J (BTBR exhibits behavioral deficits that mimic the core deficits of autism. Neuroanatomically, the BTBR strain is also characterized by a complete absence of the corpus callosum. The goal of this study was to identify novel molecular and cellular changes in the BTBR mouse, focusing on neuronal, synaptic, glial and plasticity markers in the limbic system as a model for identifying putative molecular and cellular substrates associated with autistic behaviors. Methods Forebrains of 8 to 10-week-old male BTBR and age-matched C57Bl/6J control mice were evaluated by immunohistochemistry using free-floating and paraffin embedded sections. Twenty antibodies directed against antigens specific to neurons, synapses and glia were used. Nissl, Timm and acetylcholinesterase (AchE stains were performed to assess cytoarchitecture, mossy fibers and cholinergic fiber density, respectively. In the hippocampus, quantitative stereological estimates for the mitotic marker bromodeoxyuridine (BrdU were performed to determine hippocampal progenitor proliferation, survival and differentiation, and brain-derived neurotrophic factor (BDNF mRNA was quantified by in situ hybridization. Quantitative image analysis was performed for NG2, doublecortin (DCX, NeuroD, GAD67 and Poly-Sialic Acid Neural Cell Adhesion Molecule (PSA-NCAM. Results In midline structures including the region of the absent corpus callosum of BTBR mice, the myelin markers 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase and myelin basic protein (MBP were reduced, and the oligodendrocyte precursor NG2 was increased. MBP and CNPase were expressed in small ectopic white matter bundles within the cingulate cortex. Microglia and astrocytes showed no evidence of gliosis, yet orientations of glial fibers were altered in specific white-matter areas. In the hippocampus, evidence of reduced neurogenesis included significant reductions in the number of

  8. Phosphodiesterase 4 inhibitor rolipram prevents depression- and anxiety-like behaviors in rats exposed to chronic restraint stress%磷酸二酯酶4抑制剂咯利普兰逆转慢性束缚应激诱导的大鼠抑郁和焦虑样行为

    张俊芳; 张忠敏; 赵鑫; 刘爱明; 郭洁洁; 沈璐艳; 王钦文; 王闯

    2012-01-01

    诱导了大鼠海马内PDE4D表达的上调,PKA、p-CREB及p-Ser9-GSK3β的下调.Rolipram显著逆转了上述效应,且H89显著阻断了Rolipram的药物效应.结论:Rolipram抗抑郁及抗焦虑作用不仅通过CREB/BDNF信号通路,而且还有GSK3 抑制性丝氨酸残基磷酸化信号通路的参与,且CREB介导的信号转导通路对GSK3 抑制性丝氨酸残基磷酸化信号通路发挥重要调节作用.%AIM: To discuss the impact of phosphodiesterase 4 (PDE4) inhibitor rolipram on chronic restraint stress - induced depression - and anxiety - like behaviors in rats. METHODS: (1) Forty SD rats were randomly divided into 4 weight -matched groups: unstressed animals injected with vehicle of lithium chloride (LiCl) and rolipram, restraint - stressed animals injected daily with vehicle prior to stress, restraint stress plus 100 mg/kg LiCl group and restraint stress plus 1 mg/kg rolipram group. The open field test was conducted 24 h before the first stress and drug administration, and then the rats received drugs daily 1 h prior to restraint stress (6 h/d) for 25 d. Daily body weight recording, forced swim-ming test, elevated plus - maze and open field test were conducted to determine the changes of depression - and anxiety -like behaviors. The expression of phosphorylated cAMP response element - binding protein (p - CREB) , brain - derived Reurotrophic factor ( BDNF) , p - Ser21 - glycogen synthase kinase ( GSK) 3α, p - Ser9 - GSK3β, p - Tyr279 - GSK3α, p -Tyr216 - GSK3β, total GSK3α and total GSK3β was measured by Western blotting. (2) Thirty SD rats were randomly divided into 6 groups and the cannula was surgically placed above the CA1 region in the hippocampus. Seven days after the surgery, the restraint stress was conducted for 21 d after microinjection of protein kinase A (PKA) antagonist H89 and in-traperitoneal injection of LiCl and rolipram everyday. The expression of PDE4D, PKA, p - CREB and p - Ser9 - GSK3β was measured by Western blotting. RESULTS: ( 1) No

  9. The CphAII protein from Aquifex aeolicus exhibits a metal-dependent phosphodiesterase activity

    Kupper, Michaël; Bauvois, Cédric; Frère, Jean-Marie; Galleni, Moreno; Bebrone, Carine

    2012-01-01

    The CphAII protein from the hyperthermophile Aquifex aeolicus shows the five conserved motifs of the metallo-β-lactamase (MBL) superfamily and presents 28% identity with the Aeromonas hydrophila subclass B2 CphA MBL. The gene encoding CphAII was amplified by PCR from the A. aeolicus genomic DNA and overexpressed in Escherichia coli using a pLex-based expression system. The recombinant CphAII protein was purified by a combination of heating (to denature E. coli proteins) and two steps of immob...

  10. Phosphodiesterase-1 Inhibitory Activity of Two Flavonoids Isolated from Pistacia integerrima J. L. Stewart Galls

    Abdur Rauf; Muhammad Saleem; Ghias Uddin; Bina S. Siddiqui; Haroon Khan; Muslim Raza; Syeda Zehra Hamid; Ajmal Khan; Francesco Maione; Nicola Mascolo; Vincenzo De Feo

    2015-01-01

    Pistacia integerrima is one of twenty species among the genus Pistacia. Long horn-shaped galls that develop on this plant are harvested and used in Ayurveda and Indian traditional medicine to make “karkatshringi”, a herbal medicine used for the treatment of asthma and different disorders of respiratory tract. However, until now, the molecular mechanisms of action of “karkatshringi” and its chemical characterization are partially known. This study deals with the isolation and characterization ...

  11. The role of phosphodiesterase-5 inhibitors in prostatic inflammation: a review

    Peixoto, Christina Alves; Gomes, Fabiana Oliveira dos Santos

    2015-01-01

    Clinical and basic experimental evidence indicates that chronic inflammation is the greatest factor in benign prostatic hyperplasia (BPH) progression, which is the most common cause of Lower Urinary Tract Symptoms (LUTS). The use of anti-inflammatory agents such as steroids, cyclooxygenase-2 (COX-2) and phytotherapics have been investigated as forms of treatment for various prostate diseases. Recent evidence has demonstrated that PDE5 inhibitors (PDE5Is) improve symptoms of BPH/LUTS, possibly...

  12. Porcine ecto-nucleotide pyrophosphatase/phosphodiesterase 1 (NPP1/CD203a)

    Petersen, Cathrine Bie; Hillig, Ann-Britt Nygaard; Viuff, Birgitte;

    2007-01-01

    Swine workshop cluster 9 (SWC9) antibody identifying a porcien epitope on macrophages and thymocytes was used to precipitate and characterize the molecule from biotinylated macrophages and to obtain peptide sequence by mass spectrometry. The protein was identified as ecto-nucleotide pyrophosphata...

  13. A Case Report: Consecutive Cranial Neuropathies Following the Use of Phosphodiesterase-5 Inhibitors.

    van Landingham, Suzanne W; Singman, Eric L

    2015-01-01

    We report a patient who suffered consecutive cranial neuropathies where each event was immediately preceded by the use of oral PDE-5 inhibitors. A discussion of the etiology of the events including possible interaction with other medications is included. PMID:26564936

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

    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.

  15. Stress history increases alcohol intake in relapse: Relation to phosphodiesterase 10A

    Logrip, Marian L.; Zorrilla, Eric P.

    2012-01-01

    Stressful experiences in humans 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 (Stress History) or light cues alone (Control) prior to their acquisition of alcohol self-administration (1-h sessions, fixed ratio1–3, 10...

  16. Growth of Escherichia coli Coexpressing Phosphotriesterase and Glycerophosphodiester Phosphodiesterase, Using Paraoxon as the Sole Phosphorus Source

    McLoughlin, Sean Yu; Jackson, Colin; Liu, Jian-Wei; Ollis, David L.

    2004-01-01

    Phosphotriesterases catalyze the hydrolytic detoxification of phosphotriester pesticides and chemical warfare nerve agents with various efficiencies. The directed evolution of phosphotriesterases to enhance the breakdown of poor substrates is desirable for the purposes of bioremediation. A limiting factor in the identification of phosphotriesterase mutants with increased activity is the ability to effectively screen large mutant libraries. To this end, we have investigated the possibility of ...

  17. Stimulation of neural stem cell proliferation by inhibition of phosphodiesterase 5

    Santos, Ana Isabel Reis dos

    2011-01-01

    O cGMP é uma molécula sinalizadora que actua como segundo mensageiro e os seus níveis são regulados por um equilíbrio entre a sua produção e a sua hidrólise. O cGMP é sintetizado numa reacção catalisada pela guanilil ciclase solúvel (sGC), cuja activação depende de alguns factores, em particular o óxido nítrico (NO•). O NO• e o cGMP são importantes numa grande variedade de processos biológicos e, nos últimos anos, tem sido dada atenção ao seu envolvimento na formação de novos neurónios – neur...

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

    Kruuse, Christina; Khurana, Tejvir S; Rybalkin, Sergei D; Birk, Steffen; Engel, Ulla; Edvinsson, Lars; Olesen, Jes

    less effective on the cGMP hydrolysis in cerebral arteries, and that sildenafil may not be an effective dilator of cerebral arteries under baseline conditions. We evaluated the presence of PDE5 mRNA and protein in human arteries. Furthermore, the effects of two selective PDE5 inhibitors, sildenafil 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...

  19. Bioactive Metabolites from Propolis Inhibit Superoxide Anion Radical, Acetylcholinesterase and Phosphodiesterase (PDE4)

    Abd El-Hady, Faten K.; Shaker, Kamel H.; Imhoff, Johannes F.; Zinecker, Heidi; Salah, Nesma M.; Ibrahim, Amal M.

    2013-01-01

    Cycloartane-triterpenes (cycloartenol, 3α-cycloartenol-26-oic acid and 3β-cycloartenol-26-oic acid) together with α-amyrin acetate and flavonoids (pinostrobin, tectochrysin and chrysin) were isolated from Egyptian propolis for the first time. Their antioxidant activity was evaluated with DPPH and superoxide anion radical (O2 .-). All compounds possessed both (O2 .-) scavenging as well as XOD inhibitory activity in the range of 50 – 75 %. With DPPH, only the flavonoids showed sc...

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

    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.

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

    Poulsen, Jesper Buchhave; Andersen, Kasper Røjkjær; Kjær, Karina Hansen; Durand, Fiona; Faou, Pierre; Vestergaard, Anna Lindeløv; Talbo, Gert Hoy; Hoogenraad, Nick; Brodersen, Ditlev Egeskov; Justesen, Just; Martensen, Pia Møller

    2011-01-01

    The vertebrate 2-5A system is part of the innate immune system and central to cellular antiviral defense. Upon activation by viral double-stranded RNA, 5′-triphosphorylated, 2′–5′-linked oligoadenylate polyribonucleotides (2-5As) are synthesized by one of several 2′–5′-oligoadenylate synthetases....... role in the cellular immune system, may also function in mitochondrial RNA turnover.......The vertebrate 2-5A system is part of the innate immune system and central to cellular antiviral defense. Upon activation by viral double-stranded RNA, 5′-triphosphorylated, 2′–5′-linked oligoadenylate polyribonucleotides (2-5As) are synthesized by one of several 2′–5′-oligoadenylate synthetases....... 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 for...

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

    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

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

    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 resverat

  4. Design, synthesis and biological evaluation of novel pyridine derivatives as anticancer agents and phosphodiesterase 3 inhibitors

    Abadi, Ashraf H.; Ibrahim, Tamer M.; Abouzid, Khaled M.; Lehmann, Jochen; Tinsley, Heather N.; Gary, Bernard D.; Piazza, Gary A.

    2016-01-01

    Two series of 4,6-diaryl-2-imino-1,2-dihydropyridine-3-carbonitriles and their isosteric 4,6-diaryl-2- oxo-1,2-dihydropyridine-3-carbonitriles were synthesized through a combinatorial approach. The prepared analogues were evaluated for their in vitro capacity to inhibit PDE3A and the growth of the human HT-29 colon adenocarcinoma tumor cell line. Compound 6-(4-bromophenyl)-4-(2-ethoxyphenyl)-2- imino-1,2-dihydropyridine-3-carbonitrile (Id) exhibited the strongest PDE3 inhibition when cGMP but not cAMP is the substrate with a IC50of 27 μM, which indicates a highly selective mechanism of enzyme inhibition. On the other hand, compound 6-(1,3-benzodioxol-5-yl)-4-(2-ethoxyphenyl)-2-imino-1,2- dihydropyridine-3-carbonitrile (Ii) was the most active in inhibiting colon tumor cell growth with a IC50 of 3 μM. The electronic effects, steric effects and conformational aspects of Id seem to be the most crucial for the PDE3 inhibition. Meanwhile, steric factors and the H-bonding capability seem to be the most important factors for tumor cell growth inhibitory activity. Conversely, there is no direct correlation between PDE3 inhibition and anticancer activity for the prepared compounds. An in silico docking experiment indicates the potential involvement of other potential molecular targets such as PIM-1 kinase to explain its tumor cell growth inhibitory activity. PMID:19628397

  5. AcEST: DK954747 [AcEST

    Full Text Available (Fragment) OS=Danio rerio GN... 34 7.9 tr|Q6QQG0|Q6QQG0_9MONO Nucleoprotein OS=Human metapneumovirus PE... 3...|Q49775|METH_MYCLE Methionine synthase OS=Mycobacterium leprae... 32 2.6 sp|A6L227|CNPD_BACV8 2',3'-cyclic-nucleotide 2'-phosphodies...ongensis GN=TTE1483 PE=3 SV=1 Length = 401 Score = 33.9 bits (76), Expect = 0.70 Identities = 32/116 (27%), Positives...ESI 156 >sp|A4JAN2|RPOB_BURVG DNA-directed RNA polymerase subunit beta OS=Burkholderia vietnamiensis (strain... G4 / LMG 22486) GN=rpoB PE=3 SV=1 Length = 1368 Score = 33.5 bits (75), Expect = 0.91 Identities

  6. AcEST: DK957946 [AcEST

    Full Text Available TST39A01NGRL0029_L08 657 Adiantum capillus-veneris mRNA. clone: TST39A01NGRL0029_L08. 5' end sequence...antum capillus-veneris mRNA. clone: TST39A01NGRL0029_L08. 5' end sequence. Accession DK957...Q06180|PTN2_MOUSE Tyrosine-protein phosphatase non-receptor t... 32 3.5 sp|Q313W7|CNPD_DESDG 2',3'-cyclic-nucleotide 2'-phosphodies...clone: TST39A01NGRL0029_L08, 5' (628 letters) Database: uniprot_sprot.fasta 412,525 sequences; 148,809,765 total letters Searchin...g..................................................done Score E Sequences producing significant alignmen

  7. AcEST: BP915833 [AcEST

    Full Text Available nd PSI-BLAST: a new generation of protein database search programs, Nucleic Acids Res. 25:3389-3402. Query= BP915833|Adiantum capi...d BLAST and PSI-BLAST: a new generation of protein database search programs, Nucleic Acids Res. 25:3389-3402. Query= BP915833|Adia...in cut-like 1 OS=Homo sapiens... 37 0.11 sp|A8L6J3|CNPD_FRASN 2',3'-cyclic-nucleotide 2'-phosphodiestera...beta ... 38 0.048 sp|O76329|ACTNB_DICDI Interaptin OS=Dictyostelium discoideum GN=... 38 0.048 sp|P39880|CUX1_HUMAN Homeobox prote...ntum capillus-veneris mRNA, clone: YMU001_000077_F03. (622 letters) Database: uniprot_sprot

  8. 脂多糖对不同脑成熟程度早期新生鼠髓鞘发育的影响及肿瘤坏死因子-α表达变化%Effects of lipopolysaccharide on myelination of early neonatal rat at different maturity levels and the changes of tumor necrosis factor-α expression

    安晶慧; 毛健; 周卓; 高红

    2013-01-01

    Objective To monitor the function of infection on myelination in white matter damage,neonatal Wistar rats of postnatal day 2 (P2) and postnatal day 7 (P7) were injected intraperitoneally with the same doses of lipopolysaccharides (LPS),and 2',3 '-cyclic nucleotide phosphodiesterase (CNPase) and myelin basic protein (MBP) were labeled in immature oligodendrocytes and mature oligodendrocytes.To investigate the function of tumor necrosis factor(TNF)-α according to test the change of TNF-α expression in the brain.Methods Ninty-six neonatal Wistar rats were randomly divided into four groups (each group 24 rats):group A:LPS (5.0 mg/kg) was injected intraperitoneally on P2 ; group B:LPS (5.0 mg/kg) was injected intraperitoneally on P7 ;group C1 and C2 were control groups in which equal amount of normal saline was injected intraperitoneally on P2 or P7.The expression of CNPase at 24 h after injection and MBP at P14 in brain tissue of each group were measured by immunohistochemistry and express of TNF-α mRNA at 4 h after the injection was measured by RT-PCR.Results Punctate hemorrhage in the corpus callosum,external capsule and intraventricular hemorrhage were seen in group A.Periventricular leukomalacia appeared in the corpus callosum and glial cells hyperplasia could be seen periventricular in P14 rat brains,but not found in the group B and any of the saline-injected rat brains.Compared with group C1 and C2 respectively,CNPase-positive cells showed obvious decrease in the area of white matter in periventricular in group A(106.93 ± 2.62 vs 113.67 ± 2.69,P < 0.01) and group B (96.37 ± 1.82 vs 101.65 ± 2.01,P < 0.01).Following LPS treatment in group A,the protein expression of MBP in neonatal brain decreased evidently compared with group C1 at P14 (128.21 ± 2.99 v s 134.81 ± 2.98,P < 0.01),while no significant change was found between group B and group C2(134.77 ±3.68 vs 134.81 ±2.98,P >0.05).After 4h of the LPS treatment,the level of TNF-α mRNA was

  9. A controlled trial of 6-weeks' treatment with a novel inhaled phosphodiesterase type-4 inhibitor in COPD

    Vestbo, J; Tan, L; Atkinson, G;

    2009-01-01

    of treatment, and secondary end-points included other lung function end-points and symptom scores assessed at 2-week intervals. The present study was stopped following a planned interim analysis for futility. No effect on the primary efficacy parameter, other measures of lung function or symptom...

  10. A mouse model of Rubinstein-Taybi syndrome: Defective long-term memory is ameliorated by inhibitors of phosphodiesterase 4

    Bourtchouladze, Rusiko; Lidge, Regina; Catapano, Ray; Stanley, Jennifer; Gossweiler, Scott; Romashko, Darlene; Scott, Rod; Tully, Tim

    2003-01-01

    Mice carrying a truncated form of cAMP-responsive element binding protein (CREB)-binding protein (CBP) show several developmental abnormalities similar to patients with Rubinstein-Taybi syndrome (RTS). RTS patients suffer from mental retardation, whereas long-term memory formation is defective in mutant CBP mice. A critical role for cAMP signaling during CREB-dependent long-term memory formation appears to be evolutionarily conserved. From this observation, we reasoned...

  11. Long-term niacin treatment induces insulin resistance and adrenergic responsiveness in adipocytes by adaptive downregulation of phosphodiesterase 3B

    Heemskerk, M.M.; Berg, S.A. van den; Pronk, A.C.M.; Klinken, J.B. van; Boon, M.R.; Havekes, L.M.; Rensen, P.C.N.; Willems van Dijk, K.; Harmelen, V. van

    2014-01-01

    The lipid-lowering effect of niacin has been attributed to the inhibition of cAMP production in adipocytes, thereby inhibiting intracellular lipolysis and release of nonesterified fatty acids (NEFA) to the circulation. However, long-term niacin treatment leads to a normalization of plasma NEFA level

  12. Phosphorylation of TRPC6 Channels at Thr69 Is Required for Anti-hypertrophic Effects of Phosphodiesterase 5 Inhibition*

    Nishida, Motohiro; Watanabe, Kenta; Sato, Yoji; Nakaya, Michio; Kitajima, Naoyuki; Ide, Tomomi; Inoue, Ryuji; Kurose, Hitoshi

    2010-01-01

    Activation of Ca2+ signaling induced by receptor stimulation and mechanical stress plays a critical role in the development of cardiac hypertrophy. A canonical transient receptor potential protein subfamily member, TRPC6, which is activated by diacylglycerol and mechanical stretch, works as an upstream regulator of the Ca2+ signaling pathway. Although activation of protein kinase G (PKG) inhibits TRPC6 channel activity and cardiac hypertrophy, respectively, it is unclear whether PKG suppresse...

  13. Inhibition of phosphodiesterase-3 by levosimendan is sufficient to account for its inotropic effect in failing human heart

    Ørstavik, Ø; Ata, S H; Riise, J; Dahl, C P; Andersen, G Ø; Levy, F O; Skomedal, T; Osnes, J-B; Qvigstad, E

    2014-01-01

    Background and Purpose Levosimendan is known as a calcium sensitizer, although it is also known to inhibit PDE3. We aimed to isolate each component and estimate their contribution to the increased cardiac contractility induced by levosimendan. Experimental Approach Contractile force was measured in electrically stimulated ventricular strips from explanted failing human hearts and left ventricular strips from normal male Wistar rats. PDE activity was measured in a two-step PDE activity assay on failing human ventricle. Key Results Levosimendan exerted a positive inotropic effect (PIE) reaching maximum at 10−5 M in ventricular strips from failing human hearts. In the presence of the selective PDE3 inhibitor cilostamide, the PIE of levosimendan was abolished. During treatment with a PDE4 inhibitor and a supra-threshold concentration of isoprenaline, levosimendan generated an amplified inotropic response. This effect was reversed by β-adrenoceptor blockade and undetectable in strips pretreated with cilostamide. Levosimendan (10−6 M) increased the potency of β-adrenoceptor agonists by 0.5 log units in failing human myocardium, but not in the presence of cilostamide. Every inotropic response to levosimendan was associated with a lusitropic response. Levosimendan did not affect the concentration–response curve to calcium in rat ventricular strips, in contrast to the effects of a known calcium sensitizer, EMD57033 [5-(1-(3,4-dimethoxybenzoyl)-1,2,3,4-tetrahydroquinolin-6-yl)-6-methyl-3,6-dihydro-2H-1,3,4-thiadiazin-2-one]. PDE activity assays confirmed that levosimendan inhibited PDE3 as effectively as cilostamide. Conclusions and Implications Our results indicate that the PDE3-inhibitory property of levosimendan was enough to account for its inotropic effect, leaving a minor, if any, effect to a calcium-sensitizing component. PMID:24547784

  14. Mechanisms of Cyclic Nucleotide Phosphodiesterases in Modulating T Cell Responses in Murine Graft-versus-Host Disease

    Weber, Michael; Lupp, Corinna; Stein, Pamela; Kreft, Andreas; Bopp, Tobias; WEHLER, THOMAS C.; Schmitt, Edgar; Schild, Hansjörg; Radsak, Markus P.

    2013-01-01

    Graft-versus-host disease (GvHD) is a key contributor to the morbidity and mortality after allogeneic hematopoetic stem cell transplantation (HSCT). Regulatory Foxp3+ CD4+ T cells (Treg) suppress conventional T cell activation and can control GvHD. In our previous work, we demonstrate that a basic mechanism of Treg mediated suppression occurs by the transfer of cyclic adenosine monophosphate (cAMP) to responder cells. Whether this mechanism is relevant for Treg mediated suppression of GvHD is...

  15. Adenoviral short hairpin RNA targeting phosphodiesterase 5 attenuates cardiac remodeling and cardiac dysfunction following myocardial infarction in mice

    张健

    2014-01-01

    Objective To observe the impact of PDE5shRNA on cardiac remodeling and heart function following myocardial infarction in mice.Methods Myocardial infarction(MI)was induced in mice by left coronary artery ligation.Mice were randomly assigned to sham operation group(n=6),PDE5shRNA group(n=12),common adenovirus group(n=15)and DMEM group(n=8).Four weeks post-MI,the survival rate was evaluated.

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

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

    2004-01-01

    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...

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

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

    2009-01-01

    Carbon-phosphorus lyase is a multienzyme system encoded by the phn operon that enables bacteria to metabolize organophosphonates when the preferred nutrient, inorganic phosphate, is scarce. One of the enzymes encoded by this operon, PhnP, is predicted by sequence homology to be a metal-dependent ...

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

    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. PMID:25975350

  19. Elevated leukocyte phosphodiesterase as a basis for depressed cyclic adenosine monophosphate responses in the Basenji greyhound dog model of asthma

    The BG dog manifests various characteristics of human asthma, including airway hyperreactivity to low concentrations of methacholine. Studies have suggested that airway hyperreactivity in asthma is related to inadequate intracellular cAMP responses. The authors studied cAMP characteristics in MNL from 19 BG and 14 mongrel dogs. beta-Adrenergic receptors were assessed by 125I CYP in the presence and absence of propranolol. The responses of cAMP to ISO were measured by radioimmunoassay. Adenylate cyclase activity was determined in homogenized MNL preparations by cAMP generation. PDE activity was quantitated by radioenzyme assay. Mongrel dog leukocyte ISO-stimulated cAMP levels doubled, whereas there were negligible increases in MNL from BG dogs. Basal PDE levels were higher in BG dogs than in mongrel dogs. The PDE inhibitor Ro 20-1724 restored ISO-stimulated cAMP responses in MNL of BG dogs. Adenylate cyclase activity was not lower in MNL homogenates from BG dogs than in mongrel dogs. Cells from both BG and mongrel dogs demonstrated similar receptor numbers and affinities of saturable, specific beta-adrenergic binding over a 10 pM to 400 pM range. The results suggest that depressed cAMP responses in BG dogs are due to high PDE activity rather than to a defect in the beta-adrenergic receptor adenylate cyclase system

  20. Regulation of amygdalar PKA by β-arrestin-2/phosphodiesterase-4 complex is critical for fear conditioning

    Li, Yuting; Li, Haohong; Liu, Xing; Bao, Guobin; Tao, Yezheng; Wu, Ziyan; Xia, Peng; Wu, Chunfu; Li, Baoming; Ma, Lan

    2009-01-01

    β-arrestins, key regulators of receptor signaling, are highly expressed in the central nervous system, but their roles in brain physiology are largely unknown. Here we show that β-arrestin-2 is critically involved in the formation of associative fear memory and amygdalar synaptic plasticity. In response to fear conditioning, β-arrestin-2 translocates to amygdalar membrane where it interacts with PDE-4, a cAMP-degrading enzyme, to inhibit PKA activation. Arrb2−/− mice exhibit impaired conditio...

  1. Design of Novel β-Carboline Derivatives with Pendant 5-Bromothienyl and Their Evaluation as Phosphodiesterase-5 Inhibitors

    El-Gamil, Dalia S.; Ahmed, Nermin S.; Gary, Bernard D.; Piazza, Gary A.; Engel, Matthias; Hartmann, Rolf W.; Abadi, Ashraf H.

    2016-01-01

    New derivatives with the tetrahydro-β-carboline-imidazolidinedione and tetrahydro-β-carboline-piperazinedione scaffolds and a pendant bromothienyl moiety at C-5/C-6 were synthesized and tested for their ability to inhibit PDE5 in vitro. The following SAR can be concluded: The tetracyclic scaffold is essential for PDE5 inhibition; the ethyl group is the most suitable among the adopted N-substituents on the terminal ring (hydantoin/piperazinedione); the appropriate stereochemistry of C-5/C-6 derived from the aldehyde rather than C-11a/C-12a derived from tryptophan appears crucial for inhibition of PDE5; surprisingly, derivatives with the hydantoin terminal ring are more active than their analogs with the piperazinedione ring; the selectivity versus PDE5 relative to PDE11 with cGMP as a substrate is mainly a function of the substitution and stereochemistry pattern of the external ring, in other words of the interaction with the H-loop residues of the isozymes. Thirteen derivatives showed PDE5 inhibitory activity with IC50 values in the range of 0.16–5.4 μm. Compound 8 was the most potent PDE5 inhibitor and showed selectivity towards PDE5 versus other PDEs, with a selectivity index of 49 towards PDE5 rather than PDE11 with cGMP as the substrate. PMID:23307609

  2. The effect of pre-maturation culture using phosphodiesterase type 3 inhibitor and insulin, transferrin and selenium on nuclear and cytoplasmic maturation of bovine oocytes.

    Guimarães, A L S; Pereira, S A; Kussano, N R; Dode, M A N

    2016-04-01

    This study aims to evaluate if a pre-maturation culture (PMC) using cilostamide as a meiotic inhibitor in combination with insulin, transferrin and selenium (ITS) for 8 or 24 h increases in vitro embryo production. To evaluate the effects of PMC on embryo development, cleavage rate, blastocyst rate, embryo size and total cell number were determined. When cilostamide (20 μM) was used in PMC for 8 or 24 h, 98% of oocytes were maintained in germinal vesicles. Although the majority of oocytes resumed meiosis after meiotic arrest, the cleavage and blastocyst rates were lower than the control (P 0.05) to the control. The deleterious effect of 20 μM cilostamide treatment for 24 h on a PMC was confirmed by lower cumulus cell viability, determined by trypan blue staining, in that group compared with the other groups. A lower concentration (10 μM) and shorter exposure time (8 h) minimized that effect but did not improve embryo production. More studies should be performed to determine the best concentration and the arresting period to increase oocyte competence and embryo development. PMID:25925275

  3. Silencing of the glycerophosphocholine phosphodiesterase GDPD5 alters the phospholipid metabolite profile in a breast cancer model in vivo as monitored by 31P Magnetic Resonance Spectroscopy

    Wijnen, J.P.; Jiang, L.; Greenwood, T.R.; Cheng, M; Döpkens, M.; Cao, M.D.; Bhujwalla, Z M; Krishnamachary, B; Klomp, D. W. J.; Glunde, K.

    2014-01-01

    Abnormal choline phospholipid metabolism is an emerging hallmark of cancer, which is implicated in carcinogenesis and tumor progression. The malignant metabolic phenotype is characterized by high levels of phosphocholine (PC) and relatively low levels of glycerophosphocholine (GPC) in aggressive breast cancer cells. Phosphorus Magnetic Resonance Spectroscopy (31P MRS) is able to noninvasively detect these water-soluble metabolites of choline as well as ethanolamine phospholipid metabolism. He...

  4. Characterisation of the canine rod-cone dysplasia type one gene (rod photoreceptor cGMP phosphodiesterase beta subunit (PDEB)) - a model for human retinitis pigmentosa

    Clements, P.J.M.; Gregory, C.Y. [Univ. of London (United Kingdom); Petersen-Jones, S.M. [Univ. of Edinburgh (United Kingdom)

    1994-09-01

    Rod-cone dysplasia type one (rod-1) is an early onset, autosomal recessive retinal dystrophy segregating in the Irish setter breed. It is a model for certain forms of human autosomal recessive retinitis pigmentosa (arRP) caused by mutations in the same gene, PDEB. We confirmed the codon 807 Trp to Stop mutation and were the first to show cosegregation of the mutant allele with disease in a pedigree. We believe that this currently represents the best animal model available for some aspects of arRP, since canine tissues are relatively easy to access compared to human and yet the canine eye is of comparable size, unlike that of the rd mouse. This facilitates therapeutic intervention particularly at the subretinal level. In order to more fully investigate this model we have been characterizing the PDEB gene in the normal dog. Using PCR we have partially mapped the intron/exon structure, demonstrating a very high degree of evolutionary conservation with the mouse and human genes. RT-PCR has been used to reveal expression in a variety of neural and non-neural tissues. A PCR product spanning exons 19 to 22 (which also contains the site for the rcd-1 mutation) is detected in retina but also in tissues such as visual cortex, cerebral cortex, cerebellum, lateral geniculate nucleus, adrenal gland, lung, kidney and ovary. All of these tissues gave a negative result with primers for rds/peripherin, a gene which is expressed in rods and cones. This raises interesting questions about the regulation of PDEB transcripts which is initially being investigated by Northern analysis. In addition, anchored PCR techniques have generated upstream genomic sequences and we are currently mapping the 5{prime} extent of the mRNA transcript in the retina. This will facilitate the analysis of potential upstream promoter elements involved in directing expression.

  5. Inhibition of Phosphodiesterase-4 (PDE4) activity triggers luminal apoptosis and AKT dephosphorylation in a 3-D colonic-crypt model

    Tsunoda Toshiyuki; Ota Takeharu; Fujimoto Takahiro; Doi Keiko; Tanaka Yoko; Yoshida Yasuhiro; Ogawa Masahiro; Matsuzaki Hiroshi; Hamabashiri Masato; Tyson Darren R; Kuroki Masahide; Miyamoto Shingo; Shirasawa Senji

    2012-01-01

    Abstract Background We previously established a three-dimensional (3-D) colonic crypt model using HKe3 cells which are human colorectal cancer (CRC) HCT116 cells with a disruption in oncogenic KRAS, and revealed the crucial roles of oncogenic KRAS both in inhibition of apoptosis and in disruption of cell polarity; however, the molecular mechanism of KRAS-induced these 3-D specific biological changes remains to be elucidated. Results Among the genes that were upregulated by oncogenic KRAS in t...

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

    Jakobsen, Ann-Katrine; Stougaard, Magnus

    2015-01-01

    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...... normally performed sequentially using radioactively labeled DNA substrates analyzed using gel-electrophoresis for the activity measurement and western blot or ELISA for protein measurement. We demonstrate here that our previously developed TDP1 nanosensor due to the optical real-time readout can be...... 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...

  7. Einfluss des Phosphodiesterase-Typ-5 Inhibitors Sildenafil auf den Ca2+-aktivierten K+-Kanal mit großer Leitfähigkeit in humanen Endothelzellen

    Lüdders, Dörte Wiebke

    2006-01-01

    Sildenafil ist ein bekannter Phosphodiesterasehemmer, der den cGMP-Spiegel in der Zelle erhöht. In der vorliegenden Arbeit wurde der Einfluss von Sildenafil auf den Ca2+-aktivierten K+-Kanal mit großer Leitfähigkeit (BKCa) in humanen Endothelzellen aus Umbilikalvenen (HUVEC) untersucht und ob cGMP in diesem Zusammenhang eine Rolle spielt.

  8. Long-term daily vibration exposure alters current perception threshold (CPT) sensitivity and myelinated axons in a rat-tail model of vibration-induced injury.

    Krajnak, Kristine; Raju, Sandya G; Miller, G Roger; Johnson, Claud; Waugh, Stacey; Kashon, Michael L; Riley, Danny A

    2016-01-01

    Repeated exposure to hand-transmitted vibration through the use of powered hand tools may result in pain and progressive reductions in tactile sensitivity. The goal of the present study was to use an established animal model of vibration-induced injury to characterize changes in sensory nerve function and cellular mechanisms associated with these alterations. Sensory nerve function was assessed weekly using the current perception threshold test and tail-flick analgesia test in male Sprague-Dawley rats exposed to 28 d of tail vibration. After 28 d of exposure, Aβ fiber sensitivity was reduced. This reduction in sensitivity was partly attributed to structural disruption of myelin. In addition, the decrease in sensitivity was also associated with a reduction in myelin basic protein and 2',3'- cyclic nucleotide phosphodiasterase (CNPase) staining in tail nerves, and an increase in circulating calcitonin gene-related peptide (CGRP) concentrations. Changes in Aβ fiber sensitivity and CGRP concentrations may serve as early markers of vibration-induced injury in peripheral nerves. It is conceivable that these markers may be utilized to monitor sensorineural alterations in workers exposed to vibration to potentially prevent additional injury. PMID:26852665

  9. AcEST: DK963429 [AcEST

    Full Text Available te... 32 2.5 sp|Q8TXI4|RAD50_METKA DNA double-strand break repair rad50 ATPas... 32 2.5 sp|Q15643|TRIPB_HUMAN Thyroi...sp|A5GAT3|CNPD_GEOUR 2',3'-cyclic-nucleotide 2'-phosphodiesteras... 31 5.6 sp|Q9UPV0|CE164_HUMAN Centro...tein homo... 32 3.3 sp|Q8VDC1|FYCO1_MOUSE FYVE and coiled-coil domain-containing pro... 32 3.3 sp|P46869|FLA10_CHLRE Kines...Q8N8X6|GG2L4_HUMAN Golgin subfamily A member 2-like protein 4... 30 9.6 sp|A6LQ86|CH10_CLOB8 10 kDa chaperonin OS=Clostr...t (release 56.9) Link to BlastX Result : Swiss-Prot sp_hit_id Q86YS3 Definition sp|Q86YS3|RFIP4_HUMAN Rab11 family-interacting pro

  10. 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)

    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

  11. 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

    Felding, Jakob; D. Sørensen, Morten; Poulsen, Tina D.; Larsen, Jens; Andersson, Christina; Refer, Pia; Engell, Karen; Ladefoged, Lotte G.; Thormann, Thorsten; Vinggaard, Anne Marie; Hegardt, Pontus; Søhoel, Anders; Feldbæk Nielsen, Simon

    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 of...

  12. 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.

    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. PMID:23542613

  13. The effects of phosphodiesterase-5 inhibitor sildenafil against post-resuscitation myocardial and intestinal microcirculatory dysfunction by attenuating apoptosis and regulating microRNAs expression: essential role of nitric oxide syntheses signaling

    Qian ZHANG; Wang, Guoxing; Yuan, Wei; Wu, Junyuan; Wang, Miaomiao; Li, Chunsheng

    2015-01-01

    Background Recent experimental and clinical studies have indicated the cardioprotective role of sildenafil during ischemia/reperfusion (I/R) injury. Sildenafil has been shown to attenuate postresuscitation myocardial dysfunction in piget models of ventricular fibrillation. This study was designed to investigate if administration of sildenafil will attenuate post-resuscitation myocardial dysfunction by attenuating apoptosis and regulating miRNA expressions, furthermore, ameliorating the severi...

  14. Effect of Sildenafil on Neuropathic Pain and Hemodynamics in Rats

    Huang, Lan Ji; Yoon, Myung Ha; Choi, Jeong IL; Kim, Woong Mo; Lee, Hyung Gon; Kim, Yeo Ok

    2009-01-01

    Purpose The inhibition of phosphodiesterase 5 produces an antinociception through the increase of cyclic guanosine monophosphate (cGMP), and increasing cGMP levels enhance the release of γ-aminobutyric acid (GABA). Furthermore, this phosphodiesterase 5 plays a pivotal role in the regulation of the vasodilatation associated to cGMP. In this work, we examined the contribution of GABA receptors to the effect of sildenafil, a phosphodiesterase 5 inhibitor, in a neuropathic pain rat, and assessed ...

  15. Sexual Problems

    Full Text Available ... only small improvements in response rates compared with placebo and was associated with several side effects. Phosphodiesterase inhibitors such as sildenafil, vardenafil, and tadalafil, ...

  16. Electroejaculated Baboon (Papio anubis) Sperm Requires a Higher Dosage of Pentoxifylline to Enhance Motility

    Cseh, Sandor; Chan, Philip J.; Corselli, Johannah; Bailey, Leonard L.

    2000-01-01

    Purpose: Sperm collected by electroejaculation often showpoor motility. The objective was to determine whether theaddition of the phosphodiesterase inhibitor, pentoxifylline,would stimulate electroejaculated baboon sperm motility.

  17. NCBI nr-aa BLAST: CBRC-ACAR-01-0293 [SEVENS

    Full Text Available CBRC-ACAR-01-0293 sp|Q6ZPR5|NSMA3_MOUSE Sphingomyelin phosphodiesterase 4 (Neutral sphingomyelinase... 3) (Neutral sphingomyelinase III) (nSMase3) (nSMase-3) gb|EDK97470.1| sphingomyelin phosphodiesterase 4, isoform CRA_a [Mus musculus] Q6ZPR5 5e-33 38% ...

  18. NCBI nr-aa BLAST: CBRC-DYAK-04-0096 [SEVENS

    Full Text Available CBRC-DYAK-04-0096 ref|ZP_01541736.1| diguanylate cyclase/phosphodiesterase with PAS /PAC sensor(s ... 5785.1| diguanylate cyclase/phosphodiesterase with PAS /PAC sensor(s) [Shewanella woodyi ATCC 51908] ZP_01 ...

  19. NCBI nr-aa BLAST: CBRC-PHAM-01-0930 [SEVENS

    Full Text Available CBRC-PHAM-01-0930 ref|ZP_04577172.1| diguanylate cyclase/phosphodiesterase with PAS /PAC sensor(s ... 8134.1| diguanylate cyclase/phosphodiesterase with PAS /PAC sensor(s) [Oxalobacter formigenes HOxBLS] ZP_0 ...

  20. EST Table: CK563356 [KAIKOcDNA[Archive

    Full Text Available CK563356 rswpb0_006546.y1 11/12/09 GO hit GO:0004114(3',5'-cyclic-nucleotide phosphodiesterase a ... 60 %/108 aa C32E12.2#CE45035#WBGene00016328#locus:pde-5 #cyclic nucleotide phosphodiesterase#status:Partial ...

  1. Drug: D02985 [KEGG MEDICUS

    Full Text Available D02985 Drug Arofylline (USAN/INN) C14H13ClN4O2 304.0727 304.7316 D02985.gif Anti-asthma tic [type ... IV phosphodiesterase inhibitor]; Asthma ... prophylactic; Bronchodilator phosphodiesterase (PD ...

  2. NCBI nr-aa BLAST: CBRC-OANA-01-2190 [SEVENS

    Full Text Available CBRC-OANA-01-2190 ref|YP_484804.1| diguanylate phosphodiesterase [Rhodopseudomonas ...palustris HaA2] gb|ABD05893.1| diguanylate phosphodiesterase [Rhodopseudomonas palustris HaA2] YP_484804.1 3.2 32% ...

  3. 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

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

    2006-01-01

    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 to...... demonstrate that peripheral PDE4 inhibition, produced by L-826,141, prevents the progression of EAE after the first onset of clinical signs, and suggest that similar compounds may have clinical efficacy in the treatment of MS....

  4. Tetomilast.

    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).

  5. Sexual Problems

    Full Text Available ... urinary incontinence. Medical therapy may include hormone therapy, antidepressants, phosphodiesterase inhibitors, which are drugs often used for ... therapy may improve sexual function. A group of antidepressant drugs called selective serotonin reuptake inhibitors, or SSRIs, ...

  6. Sexual Problems

    Full Text Available ... phosphodiesterase inhibitors, which are drugs often used for erectile dysfunction, and other medications. For women estrogen can be ... vardenafil, and tadalafil, are approved for treatment of erectile dysfunction in men. Women who were given sildenafil in ...

  7. Sexual Problems

    Full Text Available ... include hormone therapy, antidepressants, phosphodiesterase inhibitors, which are drugs often used for erectile dysfunction, and other medications. ... may improve sexual function. A group of antidepressant drugs called selective serotonin reuptake inhibitors, or SSRIs, often ...

  8. Sexual Problems

    Full Text Available ... You can optimize the sexual setting by enhancing communication with your partner, promoting non-sexual intimacy, and ... with placebo and was associated with several side effects. Phosphodiesterase inhibitors such as sildenafil, vardenafil, and tadalafil, ...

  9. ATP-consuming and ATP-generating enzymes secreted by pancreas

    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...

  10. 75 FR 12764 - Government-Owned Inventions; Availability for Licensing

    2010-03-17

    ... progression, significantly impacting treatment outcome. Researchers at the National Cancer Institute, NIH... involving the same tissue types. Use as experimental controls in the analysis of oncogene signaling pathways.... Commercially, phosphodiesterase inhibitors are widely used in the treatment of various disorders,...

  11. Sexual Problems

    Full Text Available ... with several side effects. Phosphodiesterase inhibitors such as sildenafil, vardenafil, and tadalafil, are approved for treatment of erectile dysfunction in men. Women who were given sildenafil in studies also had increased blood flow to ...

  12. Role of Ser102 and Ser104 as Regulators of cGMP Hydrolysis by PDE5A

    Carøe Nordgaard, Julie; Kruse, Lars Schack; Gammeltoft, Steen; Kruuse, Christina Rostrup

    2014-01-01

    Background Phosphodiesterases (PDEs) cleave phosphodiester bonds in cyclic nucleotides and play diverse roles in cell biology. PDE5A is a cytoplasmic phosphodiesterase which specifically degrades cyclic guanosine monophosphate (cGMP), a cell signaling molecule that plays important roles in neuronal signaling and vascular smooth muscle contraction. Inhibition of PDE5A induces headache resembling migraine headaches. Aim To test the hypothesis that Ser102 and Ser104 in PDE5A and/or their phospho...

  13. Effects and mechanisms of action of sildenafil citrate in human chorionic arteries

    Lynch Tadhg; O'Toole Daniel; Maharaj Chrisen H; Carney John; Jarman James; Higgins Brendan D; Morrison John J; Laffey John G

    2009-01-01

    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 ...

  14. Differential recognition of calmodulin-enzyme complexes by a conformation-specific anti-calmodulin monoclonal antibody

    An anti-calmodulin monoclonal antibody having an absolute requirement for Ca2+ has been produced from mice immunized with a mixture of calmodulin and calmodulin-binding proteins. Radioimmune assays were developed for the determination of its specificity. The epitope for this antibody resides on the COOH-terminal half of the mammalian protein. Plant calmodulin or toponin C had little reactivity. The apparent affinity of the antibody for calmodulin was increased approximately 60-fold in the presence of heart calmodulin-dependent phosphodiesterase. The presence of heart phosphodiesterase in the radioimmune assay greatly enhanced the sensitivity for calmodulin. The intrinsic calmodulin subunit of phosphorylase kinase and calmodulin which was bound to brain phosphodiesterases was also recognized with high affinity by the antibody. In direct binding experiments, most of the calmodulin-binding proteins studied were unreactive with the antibody. This selectivity allowed purification of heart and two brain calmodulin-dependent cyclic nucleotide phosphodiesterase isozymes on immobilized antibody affinity columns. The data suggest that the binding of ligands to Ca2+/calmodulin induce conformation changes in calmodulin which alter reactivity with the anti-calmodulin monoclonal antibody. The differential antibody reactivity toward calmodulin-enzyme complexes indicates that target proteins either induce very different conformations in calmodulin and/or interact with different geometries relative to the antibody binding site. The anti-calmodulin monoclonal antibody should be useful for the purification of other calmodulin-dependent phosphodiesterases as well as isozymes of phosphorylase kinase

  15. Phosphatase activities in rice-planting meadow brown soil and their responses to fertilization%草甸棕壤水稻田磷酸酶活性及对施肥措施的响应

    沈菊培; 陈振华; 陈利军

    2005-01-01

    This study is aimed to investigate the activities of phosphomonoesterase (acid-, neutral-, and alkaline-), phosphodiesterase and phosphotriesterase in a rice-planting meadow brown soil at the lower reach of Liao River, and their responses to different fertilization treatments. The results showed that there was no significant difference in soil total P and organic P contents among all treatments, but soil available P content was significantly higher in treatment OM than in other treatments. Soil acid-and neutral phosphomonoesterase had a higher activity than alkaline phosphomonoesterase and phosphodiesterase, while phosphotriesterase had the lowest activity. No significant difference was found in phosphatase activities between different fertilization treatments. Soil acid phosphomonoesterase activity had a significant correlation with soil total P and available P contents, while soil phosphodiesterase activity significantly correlated with soil organic P content.

  16. The release and characterization of some periplasm-located enzymes of Pseudomona aeruginosa.

    Bhatti, A R; DeVoe, I W; Ingram, J M

    1976-10-01

    Pseudomonas aeruginosa (ATCC 9027) releases four periplasm-located enzymes, i.e., ribonuclease (EC 3.1.4.22; EC 3.1.4.23), alkaline phosphatase (EC 3.1.3.1), cyclic-2', 3'-phosphodiesterase (EC 3.1.4.d), and 5'-nucleotidase (EC 3.1.3.5) into the medium during growth. Ribonuclease and alkaline phosphatase are classed as enzymes which are readily extracted by osmotic shock and spheroplast formation whereas cyclic-2',3'-phosphodiesterase and 5'-nucleotidase are classed as enzymes which are not readily extracted by these procedures. In view of the relative ease of extraction of the former enzymes it is suggested that the lattter enzymes, cyclic-2',3'-phosphodiesterase and 5'-nucleotidase, are bound and located in the periplasm in a manner different to ribonuclease and alkaline phosphatase. PMID:184895

  17. Effects and mechanisms of action of sildenafil citrate in human chorionic arteries.

    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. Novel anti-inflammatory agents in COPD

    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...

  19. Dicty_cDB: VFH473 [Dicty_cDB

    Full Text Available _1( X59960 |pid:none) H.sapiens mRNA for sphingomyelinase. 113 1e-23 ( P17405 ) RecName: Full=Sphingomyelin ...phosphodiesterase; ... 113 1e-23 M81780_2( M81780 |pid:none) Homo sapiens acid sphingomyelinase (SM... 113 1

  20. Functional studies of human intestinal alkaline sphingomyelinase by deglycosylation and mutagenesis

    Wu, Jun; Hansen, Gert H; Nilsson, Ake;

    2005-01-01

    Intestinal alk-SMase (alkaline sphingomyelinase) is an ectoenzyme related to the NPP (nucleotide phosphodiesterase) family. It has five potential N-glycosylation sites and predicated transmembrane domains at both the N- and C-termini. The amino acid residues forming the two metal-binding sites...

  1. NCBI nr-aa BLAST: CBRC-SARA-01-1177 [SEVENS

    Full Text Available yelinase 2) (Neutral sphingomyelinase II) (nSMase2) (nSMase-2) (Confluent 3Y1 cell-associated protein 1) isoform 1 [Bos taurus] XP_592012.3 7.4 33% ... ...CBRC-SARA-01-1177 ref|XP_592012.3| PREDICTED: similar to Sphingomyelin phosphodiesterase 3 (Neutral sphingom

  2. Cerebral haemodynamic response or excitability is not affected by sildenafil

    Kruuse, Christina Rostrup; Hansen, Adam E; Larsson, Henrik B W; Rostrup, Egill; Lauritzen, Martin

    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...

  3. Association study of PDE4B gene variants in Scandinavian schizophrenia and bipolar disorder multicenter case-control samples

    Kähler, Anna K; Otnaess, 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...

  4. Gene : CBRC-AGAM-07-0060 [SEVENS

    Full Text Available CBRC-AGAM-07-0060 U C UNKNOWN YDAM_ECOLI 2e-11 43% ref|YP_857304.1| diguanylate cyclase/phosphod ... iesterase domain 1 [Aeromonas ... hydrophila subsp. hydrophila ATCC 7966] gb|ABK3955 ... 1| diguanylate cyclase/phosphodiesterase domain 1 [Aeromonas ... hydrophila subsp. hydrophila ATCC 7966] 0.0 98% gn ...

  5. Decreased catalytic activity and altered activation properties of PDE6C mutants associated with autosomal recessive achromatopsia

    Grau, Tanja; Artemyev, Nikolai O; Rosenberg, Thomas; Dollfus, Hélène; Haugen, Olav H; Cumhur Sener, E; Jurklies, Bernhard; Andreasson, Sten; Kernstock, Christoph; Larsen, Michael; Zrenner, Eberhart; Wissinger, Bernd; Kohl, Susanne

    2011-01-01

    characterization of six missense mutations applying the baculovirus system to express recombinant mutant and wildtype chimeric PDE6C/PDE5 proteins in Sf9 insect cells. Purified proteins were analyzed using Western blotting, phosphodiesterase (PDE) activity measurements as well as inhibition assays by zaprinast and...

  6. EST Table: BY915271 [KAIKOcDNA[Archive

    Full Text Available BY915271 e96h0290 11/12/09 n.h 10/09/28 76 %/134 aa gb|EFA07940.1| hypothetical protein TcasGA2_ ... 42 %/111 aa C32E12.2#CE45035#WBGene00016328#locus:pde-5 #cyclic nucleotide phosphodiesterase#status:Partial ...

  7. EST Table: FS898541 [KAIKOcDNA[Archive

    Full Text Available FS898541 E_FL_ftes_31D05_R_0 11/12/09 GO hit GO:0004114(3',5'-cyclic-nucleotide phosphodiesteras ... 38 %/165 aa C32E12.2#CE45035#WBGene00016328#locus:pde-5 #cyclic nucleotide phosphodiesterase#status:Partial ...

  8. EST Table: CK562564 [KAIKOcDNA[Archive

    Full Text Available CK562564 rswpb0_005581.y1 11/12/09 n.h 10/09/29 81 %/167 aa ref|XP_394107.2| PREDICTED: similar ... 35 %/164 aa C32E12.2#CE45035#WBGene00016328#locus:pde-5 #cyclic nucleotide phosphodiesterase#status:Partial ...

  9. Migraine can be induced by sildenafil without changes in middle cerebral artery diameter

    Kruuse, Christina Rostrup; Thomsen, Lars Lykke; Birk, Steffen; Olesen, Jes

    GMP)-mediated vasodilatation. We examined whether sildenafil (Viagra), a selective inhibitor of cGMP-hydrolysing phosphodiesterase 5 (PDE5), which acts exclusively by increasing cGMP, can induce migraine and dilatation of cerebral arteries. We included 12 patients with migraine without aura in this double-blind, placebo...

  10. EST Table: FY039032 [KAIKOcDNA[Archive

    Full Text Available FY039032 rbmte19l23 11/11/04 68 %/169 aa emb|CAY54163.1| unnamed protein product [Heliconius mel ... 36 %/155 aa C32E12.2#CE45035#WBGene00016328#locus:pde-5 #cyclic nucleotide phosphodiesterase#status:Partial ...

  11. EST Table: FS902705 [KAIKOcDNA[Archive

    Full Text Available FS902705 E_FL_ftes_48H24_R_0 10/09/28 68 %/169 aa emb|CAY54163.1| unnamed protein product [Helic ... 39 %/179 aa C32E12.2#CE45035#WBGene00016328#locus:pde-5 #cyclic nucleotide phosphodiesterase#status:Partial ...

  12. EST Table: BY915080 [KAIKOcDNA[Archive

    Full Text Available BY915080 ceN-3158 11/12/09 GO hit GO:0003824(catalytic activity)|GO:0004114(3',5'-cyclic-nucleot ... 39 %/209 aa C32E12.2#CE45035#WBGene00016328#locus:pde-5 #cyclic nucleotide phosphodiesterase#status:Partial ...

  13. PDE-5 inhibitors: clinical points.

    Doumas, Michael; Lazaridis, Antonios; Katsiki, Niki; Athyros, Vasilios

    2015-01-01

    Erectile dysfunction is usually of vascular origin and is frequently encountered in men with cardiovascular disease. The introduction of phosphodiesterase-5 inhibitors has revolutionized the management of patients with erectile dysfunction. Currently available phosphodiesterase-5 inhibitors have distinct pharmacokinetic and pharmacodynamic properties, thus permitting for tailoring sexual therapy according to patient characteristics and needs. Phosphodiesterase-5 inhibitors possess vasorelaxing properties and exert systemic hemodynamic effects, which need to be taken into account when other cardiovascular drugs are co-administered. Special caution is needed with alpha-blockers, while the co-administration with nitrates is contra-indicated due to the risk of life-threatening hypotension. This review presents the advent of sexual therapy, describes the mechanism of action and the specific characteristics of commercially available phosphodiesterase-5 inhibitors, summarizes the efficacy and safety of these drugs with special emphasis on the cardiovascular system, and discusses the clinical criteria used for the selection of each drug for the individual patient. PMID:25392015

  14. Clearance of Pseudomonas aeruginosa Foreign-Body Biofilm Infections through Reduction of the Cyclic Di-GMP Level in the Bacteria

    Christensen, Louise D.; van Gennip, Maria; Rybtke, Morten Theil; Wu, Hong; Chiang, Wen-Chi; Alhede, Morten; Høiby, Niels; Nielsen, Thomas Eiland; Givskov, Michael; Tolker-Nielsen, Tim

    2013-01-01

    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 of the...

  15. Unusual guanylyl cyclases and cGMP signaling in Dictyostelium discoideum

    Veltman, D.M.; Bosgraaf, L.; van Haastert, P. J. M.

    2004-01-01

    cGMP is used as a second messenger in many eukaryotes. cGMP signaling requires at least three components: Guanylyl cyclases synthesize cGMP from GTP. Specific cGMP-binding proteins propagate the signal, usually by phosphorylation of their target Finally, phosphodiesterases terminate the cGMP signal

  16. NCBI nr-aa BLAST: CBRC-CFAM-09-0036 [SEVENS

    Full Text Available CBRC-CFAM-09-0036 ref|NP_726856.1| dunce CG32498-PN, isoform N [Drosophila melanogaster] sp|Q9W4 ... '-cyclic phosphodiesterase, isoforms N/G (Learning/memory ... process protein) (Protein dunce) gb|AAF45863.2| CG ...

  17. Yeast Interacting Proteins Database: YBR223C, YDR510W [Yeast Interacting Proteins Database

    Full Text Available YBR223C TDP1 Tyrosyl-DNA Phosphodiesterase I, hydrolyzes 3' and 5'-phosphotyrosyl bonds, involve ... iated proteolysis, DNA replication and septin ring dynamics ; phosphorylated at Ser2 Rows with this prey as pre ... iated proteolysis, DNA replication and septin ring dynamics ; phosphorylated at Ser2 Rows with this prey as pre ...

  18. Lithocholic acid disrupts phospholipid and sphingolipid homeostasis leading to cholestasis

    Matsubara, Tsutomu; Tanaka, Naoki; Patterson, Andrew D.; Cho, Joo-Youn; Krausz, Kristopher W.; Frank J. Gonzalez

    2011-01-01

    Lithocholic acid (LCA) is an endogenous compound associated with hepatic toxicity during cholestasis. LCA exposure in mice resulted in decreased serum lysophosphatidylcholine (LPC) and sphingomyelin levels due to elevated lysophosphatidylcholine acyltransferase (LPCAT) and sphingomyelin phosphodiesterase (SMPD) expression. Global metabolome analysis indicated significant decreases in serum palmitoyl-, stearoyl-, oleoyl- and linoleoyl-LPC levels after LCA exposure. LCA treatment also resulted ...

  19. Multiple diguanylate cyclase-coordinated regulation of pyoverdine synthesis in Pseudomonas aeruginosa

    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 intri...

  20. AGE-RELATED CHANGES IN NEUTRAL SPHINGOMYELIN-SPECIFIC PHOSPHOLIPASE C ACTIVITY IN STRIATUM, HIPPOCAMPUS, AND FRONTAL CORTEX: IMPLICATION FOR SENSITIVITY TO STRESS AND INFLAMMATION

    Previous studies show the enrichment of mammalian brain with neutral sphingomyelin specific phospholipase C (ceramide-phosphocholine phosphodiesterase, EC 3.1.4.12; N-Sase). The objective of this study was to evaluate the subcellular N-Sase activity in striatum, hippocampus, and frontal cortex. Resu...

  1. Possible Overlapping Time Frames of Acquisition and Consolidation Phases in Object Memory Processes: A Pharmacological Approach

    Akkerman, Sven; Blokland, Arjan; Prickaerts, Jos

    2016-01-01

    In previous studies, we have shown that acetylcholinesterase inhibitors and phosphodiesterase inhibitors (PDE-Is) are able to improve object memory by enhancing acquisition processes. On the other hand, only PDE-Is improve consolidation processes. Here we show that the cholinesterase inhibitor donepezil also improves memory performance when…

  2. Syntetické modely metaloenzymů katalyzující štěpení fosfodiesterové vazby

    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: 0.272, year: 2014

  3. Hemodynamic and autonomic effects of intravenous saterinone in patients with chronic heart failure

    Szabo, BM; vanVeldhuisen, DJ; vanDijk, RB; Lahiri, A; Mitrovic, [No Value; Stolzenburg, K; Brouwer, J; Lie, KI

    1997-01-01

    In this study, the hemodynamic and neurohumoral/autonomic effects of intravenous saterinone (a selective phosphodiesterase type III inhibitor, with additional alpha(1)-blocking properties) were evaluated. In a double-blind, placebo-controlled design, 36 patients with moderate to severe heart failure

  4. Expression of insulin signalling components in the sensory epithelium of the human saccule

    Degerman, Eva; Rauch, Uwe; Lindberg, Sven; Caye-Thomasen, Per; Hultgårdh, Anna; Magnusson, Måns

    2013-01-01

    exhibits expression of a calcium-sensitive cAMP/cGMP phosphodiesterase 1C (PDE1C) and the vasopressin type 2 receptor. IRS1 and PDE1C are selectively expressed in sensory epithelial hair cells, whereas the other components are expressed in sensory epithelial supporting cells or in both cell types, as...

  5. Yeast Interacting Proteins Database: YGR247W, YOR327C [Yeast Interacting Proteins Database

    Full Text Available YGR247W CPD1 Cyclic nucleotide phosphodiesterase, hydrolyzes ADP-ribose 1'', 2''-cyclic phosphate ... e to ADP-ribose 1''-phosphate ; may have a role in tRNA splicing; no detectable p ... odiesterase, hydrolyzes ADP-ribose 1'', 2''-cyclic phosphate ... to ADP-ribose 1''-phosphate ; may have a role in tR ...

  6. Penile rehabilitation after radical prostatectomy

    Fode, Mikkel; Ohl, Dana A; Ralph, David;

    2013-01-01

    focus on tissue oxygenation. Animal studies support the use of phosphodiesterase type 5 inhibitors (PDE5Is) after cavernous nerve damage but results from human studies are contradictory. The largest study to date found no long-term effect of either daily or on-demand PDE5I administration after RP...

  7. Effects of trapidil on intestinal mucosal barrier function and bacterial translocation after intestinal ischemia and reperfusion in an experimental rat model☆

    Colak, Tahsin; Ozturk, Candan; Polat, Ayse; Bagdatoglu,Ozlen; Kanik, Arzu; Turkmenoglu, Ozgur; Aydin, Suha

    2003-01-01

    Background: Intestinal ischemia and reperfusion may be the primary triggers of mucosal barrier impairment, cytokine expression, and bacterial translocation (BT). Trapidil is a phosphodiesterase and platelet-derived growth factor inhibitor that reduces lipid peroxidation and inhibits the production of cytokines.

  8. Dicty_cDB: Contig-U13945-1 [Dicty_cDB

    Full Text Available lin phosphodiesterase; ... 251 9e-65 M81780_2( M81780 |pid:none) Homo sapiens acid sphingomyelinase (SM... 2...d:none) H.sapiens mRNA for sphingomyelinase. 248 8e-64 ( Q23498 ) RecName: Full=Sphingomyelin phosphodiester... 9e-52 (Q9UAY4) RecName: Full=Putative sphingomyelin phosphodiesterase ... 207 1e-51 ( Q92484 ) RecName: Full=Acid sphingomyelinase...arrow macrophag... 198 7e-49 ( P70158 ) RecName: Full=Acid sphingomyelinase-like ...phosphodiester... 196 2e-48 (Q3ZC91) RecName: Full=Acid sphingomyelinase-like phosphodiester... 194 8e-48 AL

  9. AcEST: DK953428 [AcEST

    Full Text Available plantlets Developmental stage gametophytes with sporophytes C...bonuclease Z OS=Streptococcus thermophilus... 31 4.1 >sp|Q9GL72|RNZ2_PANTR Zinc phosphodiesterase ELAC protein 2 OS=Pan troglodytes...us-veneris mRNA. clone: TST39A01NGRL0017_L22. 5' end sequence. Accession DK953428 Tissue type prothallia with...: Swiss-Prot sp_hit_id Q9GL72 Definition sp|Q9GL72|RNZ2_PANTR Zinc phosphodiesterase ELAC protein 2 OS=Pan troglodytes Align length...S1 Ribonuclease Z OS=Staphylococcus saprophytic... 37 0.057 sp|Q8NWE6|RNZ_STAAW Ribonuclease Z OS=Staphyloco

  10. Action of radioprotectors - venoms of Central Asian snakes and radiation on the adenylate cyclase system

    Action of venoms of Central Asian snakes (Maja oxiana and Vipera labertina turahica) as radioprotectors on 3'-5'-AMP content and activity of adenylate cyclase and phosphodiesterase in homogenates of liver and spleen of rats 1 and 24 hours after irradiation (800 R) has been studied. c-AMP content and adenylate cyclase activity have been shown to decrease drastically in the organs under study after the action of ionizing radiation. Preventive administration of venoms of cobra (150 μ g/kg) and (700 μ g/kg) one hour before irradiation restores the activity of the enzyme and c - AMP content of the spleen up to 53% and of the liver, to 30%. Phosphodiesterase activity increased markedly after irradiation being practically unaffected by the protector

  11. Long-term therapy of interferon-alpha induced pulmonary arterial hypertension with different PDE-5 inhibitors: a case report

    Baumann Gert

    2005-09-01

    Full Text Available Abstract background Interferon alpha2 is widely used in hepatitis and high-risk melanoma. Interferon-induced pulmonary arterial hypertension as a side effect is rare. Case presentation We describe a melanoma patient who developed severe pulmonary arterial hypertension 30 months after initiation of adjuvant interferon alpha2b therapy. Discontinuation of interferon did not improve pulmonary arterial hypertension. This patient could be treated successfully with phosphodiesterase-5 inhibitor therapy. Conclusion This is only the 5th case of interferon-induced pulmonary arterial hypertension and the first documented case where pulmonary arterial hypertension was not reversible after termination of interferon alpha2 therapy. If interferon alpha2 treated patients develop respiratory symptoms, pulmonary arterial hypertension should be considered in the differential diagnosis. For these patients phosphodiesterase-5 inhibitors, e.g. sildenafil or vardenafil, could be an effective therapeutic approach.

  12. A comparative study of the biological activities of venoms from snakes of the genus Agkistrodon (moccasins and copperheads).

    Tan, N H; Ponnudurai, G

    1990-01-01

    1. The hemorrhagic, procoagulant, anticoagulant, phosphodiesterase, alkaline phosphomonoesterase, 5'-nucleotidase, hyaluronidase, arginine ester hydrolase, phospholipase A, L-amino acid oxidase and protease activities of 31 samples of venom from three species of Agkistrodon (A. bilineatus, A. contortrix and A. piscivorus) and 10 venom samples from five other related species belonging to the same tribe of Agkistrodontini were examined. 2. The results indicate that interspecific differences in certain biological activities of the Agkistrodon venoms are more marked than individual variations of the activities, and that these differences can be used for differentiation of the species. Particularly useful for this purpose are the phosphodiesterase, arginine ester hydrolase and anticoagulant activities of the venoms. 3. Venoms of the subspecies of A. contortrix and A. piscivorus do not differ significantly in their biological activities. PMID:2158874

  13. Synthesis, leishmanicidal and enzyme inhibitory activities of quinoline-4-carboxylic acids

    A series of quinoline-4-carboxylic acids 1-13 was synthesized and screened for their leishmanicidal, phosphodiesterase, beta-glucuronidase and urease inhibitory properties. Only compounds 3 and 7 were found to be active against leishmaniasis with IC/sub 50/ values of 76.26 +- 0.71 and 62.86 +- 0.35 macro g/ml, respectively. In phosphodiesterase assay only compound 13 showed maximum percentage inhibition (47.2%) among all the tested compounds. Compound 9 showed maximum percentage inhibition value (47.4%) against p-glucuronidase enzyme. Compound 13 showed maximum percentage inhibition value i.e. 14.10 % against urease enzyme. The structures of all the synthetic compounds were deduced by spectroscopic techniques, including /sup 1/H NMR, EI-MS, IR, and UV spectroscopy. (author)

  14. Role of Ser102 and Ser104 as Regulators of cGMP Hydrolysis by PDE5A

    Carøe Nordgaard, Julie; Kruse, Lars Schack; Gammeltoft, Steen; Kruuse, Christina

    2014-01-01

    BACKGROUND: Phosphodiesterases (PDEs) cleave phosphodiester bonds in cyclic nucleotides and play diverse roles in cell biology. PDE5A is a cytoplasmic phosphodiesterase which specifically degrades cyclic guanosine monophosphate (cGMP), a cell signaling molecule that plays important roles in...... quantified in cell extracts by standard in vitro assay using [3H] cGMP. RESULTS: The intracellular distribution of wild-type, single and double mutant PDE5A was similar and was not altered by exposure to sildenafil, cilostazol, glyceryl trinitrate, calcitonin gene-related peptide (CGRP) or sumatriptan. PDE5...... doublet. INTERPRETATION: Ser102 and Ser104 may influence the conformational flexibility of PDE5A, which may in turn influence phosphorylation status, allosteric regulation by cGMP or other as yet unknown regulatory mechanisms for PDE5A. PDE5A activation could be important in reversal of migraine...

  15. Occurrence of cyclic AMP and related enzymes during germination of Pinus pinea seeds.

    Martelli, P; Lusini, P; Bovalini, L; Bartali, R; Franchi, G G; Cinci, G

    1987-01-01

    The occurrence of cAMP, adenylate cyclase and cAMP phosphodiesterase has been tested in Pinus pinea seed during germination. The study has been carried out on dormant and imbibed seeds, seedlings, endospermic residues, roots and cotyledons. cAMP has been detected by the protein binding method and its occurrence has been verified by HPLC detections. cAMP phosphodiesterase shows a very high activity at acidic pH, while being completely inactive at pH 7.4. At this pH value, well detectable levels of adenylate cyclase have been observed. Therefore, the classical pathway of synthesis and breakdown of cAMP, already accepted for animal and bacterial cells, seems to be operating in Pinus pinea plant too. PMID:3038780

  16. Effect of vardenafil on nitric oxide synthase expression in the paraventricular nucleus of rats without sexual stimulation.

    Shin, M-S; Ko, I-G; Kim, S-E; Kim, B-K; Kim, C-J; Kim, D-H; Yoon, S-J; Kim, K-H

    2012-05-01

    Vardenafil hydrochloride (HCl) is a potent and selective phosphodiesterase type-5 (PDE-5) inhibitor that enhances nitric oxide (NO)-mediated relaxation of human corpus cavernosum and NO-induced rabbit penile erection, and enhances erectile function in patients. In the present study, the effect of vardenafil on nitric oxide synthase (NOS) and neuronal NOS expressions in the paraventricular nucleus (PVN) of rats without sexual stimulation was investigated using nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) histochemistry and neuronal NOS (nNOS) immunohistochemistry and western blot analysis. The present results showed that NOS and nNOS expression in the PVN was increased by vardenafil treatment as the dose- and duration-dependently without sexual stimulation. The phosphodiesterase type-5 inhibitor, vardenafil, augmented NOS expression in the brain without sexual stimulation. The present study suggests that sexual behaviour can be directly modulated by neurotransmitters such as nitric oxide. PMID:21950284

  17. Pharmacological analysis of feeding in a caterpillar: different transduction pathways for umami and saccharin?

    Pszczolkowski, Maciej A.; Durden, Kevin; Marquis, Juleah; Ramaswamy, Sonny B.; Brown, John J.

    2009-05-01

    Neonate larvae of codling moth, Cydia pomonella (L.), modify their behavior in the presence of saccharin, monosodium glutamate (MSG), or L(+)-2-amino-4-phosphonobutyric acid (L-AP4) by commencing their feeding earlier. Previously published pharmacological analysis demonstrated that phagostimulatory effects of MSG and L-AP4 (which elicit umami taste sensation in humans) are reversed by adenylate cyclase activator and phosphodiesterase inhibitor. In this study, by measuring the time needed to start ingestion of foliage treated with mixtures of phagostimulants and signal transduction modulators, we show that phagostimulatory effects of l-aspartate (the third hallmark umami substance) are also abolished by both adenylate cyclase activator and phosphodiesterase inhibitor, but not by phospholipase C inhibitor. However, stimulatory effects of hemicalcium saccharin were affected only by phospholipase C inhibitor. The results suggest that codling moth neonates use different transduction pathways for perception of hemicalcium saccharin and umami.

  18. 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

    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

  19. Crystallization and preliminary X-ray crystallographic analysis of human autotaxin

    The α isoform of human autotaxin has been crystallized. Diffraction data were collected to 3.0 Å resolution using synchrotron radiation. Autotaxin (ATX), which is also known as ectonucleotide pyrophosphatase/phosphodiesterase 2 (NPP2 or ENPP2) or phosphodiesterase Iα (PD-Iα), is an extracellular lysophospholipase D which generates lysophosphatidic acid (LPA) from lysophosphatidylcholine (LPC). ATX stimulates tumour-cell migration, angiogenesis and metastasis and is an attractive target for cancer therapy. For crystallographic studies, the α isoform of human ATX was overproduced in Escherichia coli, purified and crystallized using the hanging-drop vapour-diffusion method. X-ray diffraction data were collected to 3.0 Å resolution from a monoclinic crystal form belonging to space group C2, with unit-cell parameters a = 311.4, b = 147.9, c = 176.9 Å, β = 122.6°

  20. Safety and tolerability considerations in the use of sildenafil for children with pulmonary arterial hypertension

    Dodgen AL

    2015-12-01

    Full Text Available Andrew L Dodgen,1 Kevin D Hill1,2 1Department of Pediatrics, Duke University Medical Center, 2Duke Clinical Research Institute, Durham, NC, USA Abstract: Sildenafil is a phosphodiesterase type-5 inhibitor approved for treatment of pulmonary arterial hypertension (PAH in adults. Data from pediatric trials demonstrate a similar acute safety profile to the adult population but have raised concerns regarding the safety of long-term use in children. Interpretation of these trials remains controversial with major regulatory agencies differing in their recommendations – the US Food and Drug Administration recommends against the use of sildenafil for treatment of PAH in children, while the European Medicines Agency supports its use at “low doses”. Here, we review the available pediatric data regarding dosing, acute, and long-term safety and efficacy of sildenafil for the treatment of PAH in children. Keywords: phosphodiesterase inhibitor, pulmonary vasodilator, STARTS trials

  1. Dicty_cDB: VHJ154 [Dicty_cDB

    Full Text Available 5e-27 X59960_1( X59960 |pid:none) H.sapiens mRNA for sphingomyelinase. 122 7e-27 ( P17405 ) RecName: Full=S...phingomyelin phosphodiesterase; ... 122 7e-27 M81780_2( M81780 |pid:none) Homo sapiens acid sphingomyelina...se (SM... 122 7e-27 BC011304_1( BC011304 |pid:none) Mus musculus sphingomyelin phos

  2. PI3K is an upstream regulator of the PDE3B pathway of leptin signaling that may not involve activation of Akt in the rat hypothalamus

    Sahu, Abhiram; Koshinaka, Keiichi; Sahu, Maitrayee

    2013-01-01

    Leptin, the product of the obese gene, regulates energy homeostasis by acting primarily at the level of the hypothalamus. Leptin action through its receptor involves various pathways including the signal transducer and activator of transcription (STAT3), phosphatidylinositol 3-kinase (PI3K), and phosphodiesterase 3B (PDE3B)-cAMP signaling in the CNS and peripheral tissues. In the hypothalamus, leptin stimulates STAT3 activation, and induces PI3K and PDE3B activities, among others. We have pre...

  3. ERK3 regulates TDP2-mediated DNA damage response and chemoresistance in lung cancer cells

    Bian, Ka; Muppani, Naveen Reddy; Elkhadragy, Lobna; Wang, Wei; Zhang, Cheng; Chen, Tenghui; Jung, Sungyun; Seternes, Ole Morten; Long, Weiwen

    2015-01-01

    Posttranslational modifications (PTMs), such as phosphorylation and ubiquitination, play critical regulatory roles in the assembly of DNA damage response proteins on the DNA damage site and their activities in DNA damage repair. Tyrosyl DNA phosphodiesterase 2 (TDP2) repairs Topoisomerase 2 (Top2)-linked DNA damage, thereby protecting cancer cells against Top2 inhibitors-induced growth inhibition and cell death. The regulation of TDP2 activity by post-translational modifications in DNA repair...

  4. Isolation of cDNA clones encoding an enzyme from bovine cells that repairs oxidative DNA damage in vitro: homology with bacterial repair enzymes.

    Robson, C.N.; Milne, A M; Pappin, D J; Hickson, I. D.

    1991-01-01

    Ionizing radiation and radiomimetic compounds, such as hydrogen peroxide and bleomycin, generate DNA strand breaks with fragmented deoxyribose 3' termini via the formation of oxygen-derived free radicals. These fragmented sugars require removal by enzymes with 3' phosphodiesterase activity before DNA synthesis can proceed. An enzyme that reactivates bleomycin-damaged DNA to a substrate for Klenow polymerase has been purified from calf thymus. The enzyme, which has a Mr of 38,000 on SDS-PAGE, ...

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

    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...

  6. Biochemical assays for the discovery of TDP1 inhibitors

    Marchand, Christophe; Huang, Shar-yin N.; Dexheimer, Thomas S.; Lea, Wendy A.; Mott, Bryan T.; Chergui, Adel; Naumova, Alena; Stephen, Andrew G.; Rosenthal, Andrew S.; Rai, Ganesha; Murai, Junko; Gao, Rui; Maloney, David J.; Jadhav, Ajit; Jorgensen, William L.

    2014-01-01

    Drug screening against novel targets is warranted to generate biochemical probes and new therapeutic drug leads. Tyrosyl-DNA-phosphodiesterases 1 and 2 (TDP1 and TDP2) are two DNA repair enzymes that have yet to be successfully targeted. TDP1 repairs topoisomerase I-, alkylation-, and chain terminator-induced DNA damage, while TDP2 repairs topoisomerase II-induced DNA damage. Here we report the quantitative high-throughput screening (qHTS) of the NIH Molecular Libraries Small Molecule Reposit...

  7. Stress-dependent dilated cardiomyopathy in mice with cardiomyocyte-restricted inactivation of cyclic GMP-dependent protein kinase I

    Frantz, Stefan; Klaiber, Michael; Baba, Hideo A.; Oberwinkler, Heinz; Völker, Katharina; Gaßner, Birgit; Bayer, Barbara; Abeßer, Marco; Schuh, Kai; Feil, Robert; Hofmann, Franz; Kuhn, Michaela

    2016-01-01

    Aims: Cardiac hypertrophy is a common and often lethal complication of arterial hypertension. Elevation of myocyte cyclic GMP levels by local actions of endogenous atrial natriuretic peptide (ANP) and C-type natriuretic peptide (CNP) or by pharmacological inhibition of phosphodiesterase-5 was shown to counter-regulate pathological hypertrophy. It was suggested that cGMP-dependent protein kinase I (cGKI) mediates this protective effect, although the role in vivo is under debate. Here, we inves...

  8. Comparison Between Tadalafil Plus Paroxetine and Paroxetine Alone in the Treatment of Premature Ejaculation

    Moudi, Emadouddin; Kasaeeyan, Ali Akbar

    2016-01-01

    Background: Several recent studies have investigated the therapeutic role of phosphodiesterase type 5 (PDE5) inhibitors in premature ejaculation (PE) used in the treatment of erectile dysfunction. Objectives: In the present research, the efficacy of paroxetine alone and paroxetine plus tadalafil was compared in patients referred because of premature ejaculation. Patients and Methods: This quasi-experimental study was performed on 100 consecutive 17 to 49-year-old potent men with premature eja...

  9. Advances in treating premature ejaculation

    Çayan, Selahittin; Şerefoğlu, Ege Can

    2014-01-01

    In spite of its high prevalence and long history, the ambiguity regarding the definition, epidemiology and management of premature ejaculation continues. Topical anesthetic creams and daily or on-demand selective serotonin reuptake inhibitor (SSRI) treatment forms the basis of pharmacotherapy for premature ejaculation today, in spite of low adherence by patients. Psychotherapy may improve the outcomes when combined with these treatment modalities. Tramadol and phosphodiesterase type 5 inhibit...

  10. Medical therapy for premature ejaculation

    Mohee, Amar; Eardley, Ian

    2011-01-01

    Premature ejaculation (PE) is a common male sexual dysfunction. Advances in PE research have been hampered owing to a nonstandardized definition of PE, until the definition by the International Society of Sexual Medicine (ISSM) in 2009. Once the diagnosis of PE is established through a thorough history, a variety of medical therapies is available, including tricyclic antidepressants, selective serotonin reuptake inhibitors (SSRIs), centrally acting opiates, phosphodiesterase 5 inhibitors and ...

  11. Function, structure, and mechanism in bacterial photosensory LOV proteins

    Herrou, Julien; Crosson, Sean

    2011-01-01

    LOV domains are protein photosensors conserved in bacteria, archaea, plants and fungi that detect blue light via a flavin cofactor. In the bacterial kingdom, LOV domains are present in both chemotrophic and phototrophic species, where they are found N-terminally of signaling and regulatory domains such as sensor histidine kinases, diguanylate cyclases/phosphodiesterases, DNA-binding domains, and σ factor regulators. In this review, we describe the current state of knowledge on the function of...

  12. Effects of Zaprinast and Rolipram on Olfactory and Visual Memory in the Social Transmission of Food Preference and Novel Object Recognition Tests in Mice

    Furuzan Akar; Oguz Mutlu; Ipek K. Celikyurt; Emine Bektas; Mehmet H. Tanyeri; Guner Ulak; Pelin Tanyeri; Faruk Erden

    2014-01-01

    The role of phosphodiesterase (PDE) inhibitors in central nervous system has been investigated and shown to stimulate neuronal functions and increase neurogenesis in Alzheimer patients. The aim of this study is to investigate effect of PDE5 inhibitor zaprinast and PDE4 inhibitor rolipram on visual memory in novel object recognition (NOR) test, on olfactory memory in social transmission of food preference (STFP) test, and also on locomotion and anxiety in open field test in naive mice. Male Ba...

  13. Modifications of retinal neurons in a mouse model of retinitis pigmentosa

    Strettoi, Enrica; Pignatelli, Vincenzo

    2000-01-01

    Animal models of retinitis pigmentosa include the rd mouse, in which a mutation of a rod-specific phosphodiesterase leads to the rapid loss of photoreceptors during the early postnatal life. Very little is known about changes occurring in inner retinal neurons after photoreceptor loss. These changes are important in view of the possibility of restoring vision in retinas with photoreceptor degeneration by means of cell transplantation or direct stimulation of inner ...

  14. The marine toxin, Yessotoxin, induces apoptosis and increases mitochondrial activity

    Andrea Fernandez-Araujo; M. Mercedes Rodríguez Vieytes; Ana María Botana

    2014-01-01

    Abstract: Yessotoxin (YTX) group are phycotoxins produced by different species of dinoflagellates. YTX activates the Phosphodiesterases (PDEs). This group of toxins can be consumed by humans, however no intoxication events are reported. Controversial results by measuring cell viability with MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazoliumbromide) assay had been described. In this paper mitochondrial activity and cell death are studied through different viability tests, flow cytometry...

  15. Cystic Fibrosis Transmembrane Conductance Regulator Activation by Roflumilast Contributes to Therapeutic Benefit in Chronic Bronchitis

    Lambert, James A.; Raju, S. Vamsee; Tang, Li Ping; McNicholas, Carmel M.; Li, Yao; Courville, Clifford A.; Farris, Roopan F.; Coricor, George E.; Smoot, Lisa H.; Mazur, Marina M.; Dransfield, Mark T; Bolger, Graeme B.; Rowe, Steven M

    2014-01-01

    Cigarette smoking causes acquired cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction and is associated with delayed mucociliary clearance and chronic bronchitis. Roflumilast is a clinically approved phosphodiesterase 4 inhibitor that improves lung function in patients with chronic bronchitis. We hypothesized that its therapeutic benefit was related in part to activation of CFTR. Primary human bronchial epithelial (HBE) cells, Calu-3, and T84 monolayers were exposed to whol...

  16. Expression of NPP1 is regulated during atheromatous plaque calcification

    Nitschke, Yvonne; Hartmann, Simone; Torsello, Giovanni; Horstmann, Rüdiger; Seifarth, Harald; Weissen-Plenz, Gabriele; Rutsch, Frank

    2009-01-01

    Abstract Mutations of the ENPP1 gene encoding ecto-nucleotide pyrophosphatase/phosphodiesterase 1 (NPP1) are associated with medial calcification in infancy. While the inhibitory role of matrix proteins such as osteopontin (OPN) with respect to atherosclerotic plaque calcification has been established, the role of NPP1 in plaque calcification is not known. We assessed the degree of plaque calcification (computed tomography), NPP1 and OPN localization (immunohistochemistry) and expression (RT-...

  17. Glial cell modulators attenuate methamphetamine self-administration in the rat

    SNIDER, Sarah E.; Hendrick, Elizabeth S; BEARDSLEY, PATRICK M.

    2013-01-01

    Neuroinflammation induced by activated microglia and astrocytes can be elicited by drugs of abuse. Methamphetamine administration activates glial cells and increases proinflammatory cytokine production, and there is recent evidence of a linkage between glial cell activation and drug abuse-related behavior. We have previously reported that ibudilast (AV411; 3-isobutyryl-2-isopropylpyrazolo-[1,5-a]pyridine), which inhibits phosphodiesterase (PDE) and pro-inflammatory activity, blocks reinstatem...

  18. Le medicament du mois. Le vardenafil (Levitra).

    Scheen, André

    2003-01-01

    Vardenafil (Levitra), recently launched in Belgium by Bayer and Glaxo-SmithKline, is a new drug that potently and selectively inhibits phosphodiesterase type 5 (PDE5) in the cavernosum tissue of the penis. Inhibition of PDE5 blocks the hydrolysis of cyclic guanosine monophosphate (GMPc) and results in increased arterial blood flow leading to enlargement of the corpus cavernosum and resulting in erection. In controlled clinical trials, vardenafil at least doubled the rate of successful erectio...

  19. Non pigmenting mucosal fixed drug eruption due to tadalafil: A report of two cases.

    Das, Sudip; Das, Suchibrata; Chowdhury, Joyeeta; Bhanja, Dulal Chandra

    2014-04-01

    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. PMID:24860753

  20. Non pigmenting mucosal fixed drug eruption due to tadalafil: A report of two cases

    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.