Abstract
A perplexing phenomenon identified in several tissues is the lack of correlation between inhibition of phosphodiesterase 4 (PDE4) and certain functional responses such as smooth muscle relaxation, gastric acid secretion and cAMP accumulation. Interpretation of these data is complicated further by the finding that function correlates with the ability of PDE4 inhibitors to displace [3H]rolipram [4-(3-cyclopentenyloxy-4-methoxyphenyl)-2-pyrrolidone] from a high-affinity site in rat brain that is apparently distinct from the catalytic centre of the enzyme. We have investigated this discrepancy by using guinea pig macrophages as a source of PDE4 and have confirmed that the ability of a limited range of structurally dissimilar PDE inhibitors (Org 20241, nitraquazone and the enantiomers of rolipram and benafentrine) to increase cAMP content did not correlate with their potency as inhibitors of partly purified PDE4, whereas a significant linear and rank order correlation was found when cAMP accumulation was related to the displacement of [3H]R-(-)-rolipram from a specific site identified in macrophage lysates. An explanation for these data emerged from the finding that the IC50 values and rank order of potency of these compounds for inhibition of partly purified PDE4 and the native (membrane-bound) form of the same enzyme were distinct. Similarly, no correlation was found when membrane-bound PDE4 was compared with the same enzyme that had been solubilized with Triton X-100. These unexpected results were attributable to a selective decrease in the potency of those inhibitors [nitraquazone, R-(-)- and S-(+)-rolipram] that interacted preferentially with the rolipram binding site. Indeed, if membrane-bound PDE4 was used as the enzyme preparation, excellent linear and rank order correlations between inhibition of cAMP hydrolysis, displacement of [3H]R-(-)-rolipram and cAMP accumulation were found, which improved further in the presence of the vanadyl (Vo)/2. GSH complex. Moreover, using Vo/2.GSH-treated membranes, the IC50 values of nitraquazone and the enantiomers of rolipram for the inhibition of PDE4 approached their affinity for the rolipram binding site. Collectively, these data suggest that the rolipram binding site and the catalytic domain on CPPDE4 might represent part of the same entity. In addition, these results support the concept that PDE4 can exist in different conformational states [Barnett, Manning, Cieslinski, Burman, Christensen and Torphy (1995) J. Pharmcol. Exp. Ther. 273, 674-679] and provide evidence that the cAMP content in macrophages is regulated primarily by a conformer of PDE4 for which rolipram has nanomolar affinity.
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- Alvarez R., Sette C., Yang D., Eglen R. M., Wilhelm R., Shelton E. R., Conti M. Activation and selective inhibition of a cyclic AMP-specific phosphodiesterase, PDE-4D3. Mol Pharmacol. 1995 Oct;48(4):616–622. [PubMed] [Google Scholar]
- Barnette M. S., Grous M., Cieslinski L. B., Burman M., Christensen S. B., Torphy T. J. Inhibitors of phosphodiesterase IV (PDE IV) increase acid secretion in rabbit isolated gastric glands: correlation between function and interaction with a high-affinity rolipram binding site. J Pharmacol Exp Ther. 1995 Jun;273(3):1396–1402. [PubMed] [Google Scholar]
- Barnette M. S., Manning C. D., Cieslinski L. B., Burman M., Christensen S. B., Torphy T. J. The ability of phosphodiesterase IV inhibitors to suppress superoxide production in guinea pig eosinophils is correlated with inhibition of phosphodiesterase IV catalytic activity. J Pharmacol Exp Ther. 1995 May;273(2):674–679. [PubMed] [Google Scholar]
- Beavo J. A., Conti M., Heaslip R. J. Multiple cyclic nucleotide phosphodiesterases. Mol Pharmacol. 1994 Sep;46(3):399–405. [PubMed] [Google Scholar]
- Beavo J. A., Reifsnyder D. H. Primary sequence of cyclic nucleotide phosphodiesterase isozymes and the design of selective inhibitors. Trends Pharmacol Sci. 1990 Apr;11(4):150–155. doi: 10.1016/0165-6147(90)90066-H. [DOI] [PubMed] [Google Scholar]
- Cheng Y., Prusoff W. H. Relationship between the inhibition constant (K1) and the concentration of inhibitor which causes 50 per cent inhibition (I50) of an enzymatic reaction. Biochem Pharmacol. 1973 Dec 1;22(23):3099–3108. doi: 10.1016/0006-2952(73)90196-2. [DOI] [PubMed] [Google Scholar]
- Conti M., Nemoz G., Sette C., Vicini E. Recent progress in understanding the hormonal regulation of phosphodiesterases. Endocr Rev. 1995 Jun;16(3):370–389. doi: 10.1210/edrv-16-3-370. [DOI] [PubMed] [Google Scholar]
- Dent G., Giembycz M. A., Evans P. M., Rabe K. F., Barnes P. J. Suppression of human eosinophil respiratory burst and cyclic AMP hydrolysis by inhibitors of type IV phosphodiesterase: interaction with the beta adrenoceptor agonist albuterol. J Pharmacol Exp Ther. 1994 Dec;271(3):1167–1174. [PubMed] [Google Scholar]
- Dent G., Giembycz M. A., Rabe K. F., Barnes P. J. Inhibition of eosinophil cyclic nucleotide PDE activity and opsonised zymosan-stimulated respiratory burst by 'type IV'-selective PDE inhibitors. Br J Pharmacol. 1991 Jun;103(2):1339–1346. doi: 10.1111/j.1476-5381.1991.tb09790.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Downes C. P., Hawkins P. T., Irvine R. F. Inositol 1,3,4,5-tetrakisphosphate and not phosphatidylinositol 3,4-bisphosphate is the probable precursor of inositol 1,3,4-trisphosphate in agonist-stimulated parotid gland. Biochem J. 1986 Sep 1;238(2):501–506. doi: 10.1042/bj2380501. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Giembycz M. A., Barnes P. J. Selective inhibition of a high affinity type IV cyclic AMP phosphodiesterase in bovine trachealis by AH 21-132. Relevance to the spasmolytic and anti-spasmogenic actions of AH 21-132 in the intact tissue. Biochem Pharmacol. 1991 Jul 15;42(3):663–677. doi: 10.1016/0006-2952(91)90330-8. [DOI] [PubMed] [Google Scholar]
- Giembycz M. A. Could isoenzyme-selective phosphodiesterase inhibitors render bronchodilator therapy redundant in the treatment of bronchial asthma? Biochem Pharmacol. 1992 May 28;43(10):2041–2051. doi: 10.1016/0006-2952(92)90160-k. [DOI] [PubMed] [Google Scholar]
- Glaser T., Traber J. TVX 2706--a new phosphodiesterase inhibitor with antiinflammatory action. Biochemical characterization. Agents Actions. 1984 Oct;15(3-4):341–348. doi: 10.1007/BF01972369. [DOI] [PubMed] [Google Scholar]
- Gärtner I. Separation of human eosinophils in density gradients of polyvinylpyrrolidone-coated silica gel (Percoll). Immunology. 1980 May;40(1):133–136. [PMC free article] [PubMed] [Google Scholar]
- Harris A. L., Connell M. J., Ferguson E. W., Wallace A. M., Gordon R. J., Pagani E. D., Silver P. J. Role of low Km cyclic AMP phosphodiesterase inhibition in tracheal relaxation and bronchodilation in the guinea pig. J Pharmacol Exp Ther. 1989 Oct;251(1):199–206. [PubMed] [Google Scholar]
- Nicholson C. D., Challiss R. A., Shahid M. Differential modulation of tissue function and therapeutic potential of selective inhibitors of cyclic nucleotide phosphodiesterase isoenzymes. Trends Pharmacol Sci. 1991 Jan;12(1):19–27. doi: 10.1016/0165-6147(91)90484-a. [DOI] [PubMed] [Google Scholar]
- Nicholson C. D., Shahid M., Bruin J., Barron E., Spiers I., de Boer J., van Amsterdam R. G., Zaagsma J., Kelly J. J., Dent G. Characterization of ORG 20241, a combined phosphodiesterase IV/III cyclic nucleotide phosphodiesterase inhibitor for asthma. J Pharmacol Exp Ther. 1995 Aug;274(2):678–687. [PubMed] [Google Scholar]
- Saccomano N. A., Vinick F. J., Koe B. K., Nielsen J. A., Whalen W. M., Meltz M., Phillips D., Thadieo P. F., Jung S., Chapin D. S. Calcium-independent phosphodiesterase inhibitors as putative antidepressants: [3-(bicycloalkyloxy)-4-methoxyphenyl]-2-imidazolidinones. J Med Chem. 1991 Jan;34(1):291–298. doi: 10.1021/jm00105a045. [DOI] [PubMed] [Google Scholar]
- Schmiechen R., Schneider H. H., Wachtel H. Close correlation between behavioural response and binding in vivo for inhibitors of the rolipram-sensitive phosphodiesterase. Psychopharmacology (Berl) 1990;102(1):17–20. doi: 10.1007/BF02245738. [DOI] [PubMed] [Google Scholar]
- Schneider H. H., Schmiechen R., Brezinski M., Seidler J. Stereospecific binding of the antidepressant rolipram to brain protein structures. Eur J Pharmacol. 1986 Aug 7;127(1-2):105–115. doi: 10.1016/0014-2999(86)90210-4. [DOI] [PubMed] [Google Scholar]
- Schwabe U., Miyake M., Ohga Y., Daly J. W. 4-(3-Cyclopentyloxy-4-methoxyphenyl)-2-pyrrolidone (ZK 62711): a potent inhibitor of adenosine cyclic 3',5'-monophosphate phosphodiesterases in homogenates and tissue slices from rat brain. Mol Pharmacol. 1976 Nov;12(6):900–910. [PubMed] [Google Scholar]
- Schwartz J. P., Passonneau J. V. Cyclic AMP-mediated induction of the cyclic AMP phosphodiesterase of C-6 glioma cells. Proc Natl Acad Sci U S A. 1974 Oct;71(10):3844–3848. doi: 10.1073/pnas.71.10.3844. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Semmler J., Wachtel H., Endres S. The specific type IV phosphodiesterase inhibitor rolipram suppresses tumor necrosis factor-alpha production by human mononuclear cells. Int J Immunopharmacol. 1993 Apr;15(3):409–413. doi: 10.1016/0192-0561(93)90052-z. [DOI] [PubMed] [Google Scholar]
- Shahid M., van Amsterdam R. G., de Boer J., ten Berge R. E., Nicholson C. D., Zaagsma J. The presence of five cyclic nucleotide phosphodiesterase isoenzyme activities in bovine tracheal smooth muscle and the functional effects of selective inhibitors. Br J Pharmacol. 1991 Oct;104(2):471–477. doi: 10.1111/j.1476-5381.1991.tb12453.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Souness J. E., Maslen C., Scott L. C. Effects of solubilization and vanadate/glutathione complex on inhibitor potencies against eosinophil cyclic AMP-specific phosphodiesterase. FEBS Lett. 1992 May 11;302(2):181–184. doi: 10.1016/0014-5793(92)80435-j. [DOI] [PubMed] [Google Scholar]
- Souness J. E., Scott L. C. Stereospecificity of rolipram actions on eosinophil cyclic AMP-specific phosphodiesterase. Biochem J. 1993 Apr 15;291(Pt 2):389–395. doi: 10.1042/bj2910389. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Souness J. E., Thompson W. J., Strada S. J. Adipocyte cyclic nucleotide phosphodiesterase activation by vanadate. J Cyclic Nucleotide Protein Phosphor Res. 1985;10(4):383–396. [PubMed] [Google Scholar]
- Swinnen J. V., Tsikalas K. E., Conti M. Properties and hormonal regulation of two structurally related cAMP phosphodiesterases from the rat Sertoli cell. J Biol Chem. 1991 Sep 25;266(27):18370–18377. [PubMed] [Google Scholar]
- Thompson W. J., Appleman M. M. Multiple cyclic nucleotide phosphodiesterase activities from rat brain. Biochemistry. 1971 Jan 19;10(2):311–316. [PubMed] [Google Scholar]
- Thompson W. J., Tan B. H., Strada S. J. Activation of rabbit liver high affinity cAMP (type IV) phosphodiesterase by a vanadyl-glutathione complex. Characterization of the role of the sulfhydryl. J Biol Chem. 1991 Sep 15;266(26):17011–17019. [PubMed] [Google Scholar]
- Torphy T. J., DeWolf W. E., Jr, Green D. W., Livi G. P. Biochemical characteristics and cellular regulation of phosphodiesterase IV. Agents Actions Suppl. 1993;43:51–71. doi: 10.1007/978-3-0348-7324-6_5. [DOI] [PubMed] [Google Scholar]
- Torphy T. J., Stadel J. M., Burman M., Cieslinski L. B., McLaughlin M. M., White J. R., Livi G. P. Coexpression of human cAMP-specific phosphodiesterase activity and high affinity rolipram binding in yeast. J Biol Chem. 1992 Jan 25;267(3):1798–1804. [PubMed] [Google Scholar]