Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.1.4.1 (phosphodiesterase)
18,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Atopic dermatitis, allergic rhinitis and asthma are a common group of diseases with a familial predisposition. At present there is no suitable predictive or diagnostic marker. Adults with atopic dermatitis or allergic respiratory disease have elevated mononuclear leukocyte cAMP-phosphodiesterase activity. This activity correlates closely with histamine release from basophils. We investigated newborn leukocyte phosphodiesterase activity and histamine release in umbilical cord blood. Phosphodiesterase activity was significantly elevated in cord blood leukocytes of 81 children with a positive history of atopy in first degree relatives, compared to 33 children with a negative history (p less than 0.025). In contrast to adults there was no correlation between phosphodiesterase activity and histamine release. Our studies suggest that elevated phosphodiesterase activity is a primary, genetically linked defect. Fetal basophils would appear to possess cytophilic IgE since they are capable of immunologically stimulated histamine release even without passive, in vitro IgE sensitization. In addition, there are functional differences between adult and cord blood basophils. Longitudinal studies may determine if elevated phosphodiesterase is predictive of atopic states.
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PMID:Cyclic AMP-phosphodiesterase activity and histamine release in cord blood leukocyte preparations. 240 31

The atopic conditions, atopic dermatitis, asthma, and allergic rhinitis, may arise as a result of infiltrating bone marrow-derived cells into skin or respiratory mucosae. Release of inflammatory factors from these cells could account for cutaneous vascular instability and pruritus in atopic dermatitis. Erythema and itch have been induced by experimental stress interviews and by blind food challenges. In the latter, increased plasma histamine was detected and correlated with cutaneous reactions. Basophils from patients with atopic dermatitis have increased histamine release after exposure to immunologic or nonimmunologic lectin stimuli. This increased releasability may relate to inadequate cyclic AMP regulation of cell function. We have found that leukocytes of patients with atopic dermatitis have elevated phosphodiesterase activity and consequently reduced intracellular cyclic AMP. Exposure of the cells to a phosphodiesterase inhibitor caused considerable reduction in histamine release. Similarly, exposure of atopic B lymphocytes to a phosphodiesterase inhibitor greatly reduced the high spontaneous IgE synthesis in mononuclear leukocyte cultures. Elevated leukocyte phosphodiesterase activity may also serve as a marker for the atopic diathesis. We have found elevated enzyme activity in umbilical cord blood from newborns with atopic parents, suggesting that this defect may relate to a genetically determined defect. These studies have provided insight into basic abnormalities associated with atopic dermatitis and the atopic diathesis. Defects of regulatory mechanisms in immune and inflammatory cells may help explain the seemingly disparate disorders of physiologic, pharmacologic, and immunologic systems in atopy.
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PMID:Immunopharmacology of the atopic diseases. 240 83

Atopic dermatitis (AD) is a familial inflammatory skin disorder, which is characterized by extreme pruritus, the typical morphology and distribution, the chronic or chronically relapsing course, and the personal or family case history of atopy (asthma, allergic rhinitis, atopic dermatitis); moreover, we find a variety of additional features, which are either less specific or relatively rare. Although this disease has been well-known since the beginning of the century, we have not clearly understood its pathogenesis so far. This article reviews the reported deviations of the immune system and the alterations of the mediators of inflammation as well as the abnormalities of cyclic nucleotide regulation. These findings are correlated to the clinical symptoms. The following topics have been dealt with in detail: association with HLA-antigens, elevation of serum IgE and generation of IgE immune complexes, numerical and functional deficiencies of T-suppressor cells, involvement of granulocytes, alterations of mediators of inflammation, and particularly, observations on the cAMP-phosphodiesterase. These extremely complex findings, which are based on the interaction between disregulation of the autonomous nervous system and alterations of the immune system, may provide a better understanding of the pathogenesis of atopic dermatitis.
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PMID:[Pathogenesis of atopic dermatitis]. 243 53

Atopic dermatitis (AD) is a familial inflammatory skin disorder which is characterized by extreme pruritus, the typical morphology and distribution, the chronic or chronically relapsing time course and the personal or family history of atopy (asthma, allergic rhinitis, atopic dermatitis). However, there exists a variety of additional features which are either less specific or relatively rare. Although this disease has been well-known since the beginning of the century, the pathogenesis is not clearly understood at present. This review summarizes the reported deviations of the immune system as well as the alterations of the mediators of inflammation and the abnormalities of cyclic nucleotide regulation. These findings will be correlated with clinical symptoms. In particular the following topics were taken into consideration: association with HLA-antigens, elevation of serum IgE and generation of IgE immune complexes, numerical and functional deficiencies of T-suppressor cells, involvement of granulocytes, alterations of mediators of inflammation and especially the observations on the cyclic adenosine monophosphate (cAMP)-phosphodiesterase. These extremely complex findings based on the interaction between disregulation of the autonomous nervous system and alterations of the immune system may provide a better understanding of the pathogenesis of atopic dermatitis.
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PMID:[Pathogenesis of atopic dermatitis]. 299 74

Previous studies have documented that leukocytes from atopic individuals show reduced cyclic AMP (cAMP) responsiveness to isoproterenol, histamine, and prostaglandin E1. We questioned whether this blunted response was due to rapid enzymic breakdown of cAMP. We measured cAMP-phosphodiesterase activity in mononuclear leukocytes of patients with atopic dermatitis and allergic rhinitis and noted consistent, significantly elevated levels. Kinetic studies showed differences in two of three leukocyte enzyme forms between normals and patients. Isolated lymphocytes from atopic dermatitis patients lacked a low Km phosphodiesterase form and showed an increase in the high Km, high-activity form seen in normal monocytes. The increased phosphodiesterase activity provides an explanation for the blunted cAMP responsiveness in atopic leukocytes and may reflect a basic biochemical characteristic relevant to abnormal immunocellular regulation in atopic disease.
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PMID:Elevated leukocyte cyclic AMP-phosphodiesterase in atopic disease: a possible mechanism for cyclic AMP-agonist hyporesponsiveness. 612 57

We determined the cyclic adenosine monophosphate phosphodiesterase (cAMP-PDE) activity in peripheral blood mononuclear leucocytes from 100 patients with atopic dermatitis (AD) aged 13-57 years (mean +/- SD, 29.8 +/- 17.7 years). The correlation between cAMP-PDE activity and clinical parameters such as the severity of eczema and a personal or family predisposition to atopic respiratory diseases (ARD) (asthma or allergic rhinitis) was examined. Although the enzymic activity varied from normal to very high in the AD patients, cAMP-PDE activity was significantly (P < 0.005) elevated in AD patients (42.1 +/- 22.0 units) as compared with the normal controls (12.4 +/- 5.6) and clinical control subjects (13.4 +/- 9.5). In contrast, we found no correlation between cAMP-PDE activity and the severity of eczema when AD patients were classified into four categories (remission, mild, moderate and severe) according to the extent of their skin involvement. Furthermore, we found that systemic corticosteroid therapy in severe AD patients did not alter the cAMP-PDE activity. cAMP-PDE activity was significantly (P < 0.01) higher in those AD patients who had a personal history of ARD (47.2 +/- 11.2) than in AD patients with a family history of ARD (37.2 +/- 17.4) and those without a personal or family history ('pure' AD) (34.4 +/- 19.8). Nevertheless, the cAMP-PDE activity was significantly higher even in 'pure' AD patients than in the controls. These results suggest that an elevation of cAMP-PDE activity is closely related to a predisposition to respiratory atopy, and does not follow inflammation in AD patients.
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PMID:Cyclic adenosine monophosphate phosphodiesterase activity in peripheral blood mononuclear leucocytes from patients with atopic dermatitis: correlation with respiratory atopy. 966 32

Increased cyclic AMP (cAMP)-phosphodiesterase (PDE) activity in peripheral blood leucocytes is associated with the immunological inflammation that characterizes allergic diseases, such as atopic dermatitis and allergic rhinitis. Recently, it has been found that IL-13 has similar biological functions to IL-4. The aim of this study was to investigate the possible involvement of cAMP-PDE activity on IL-13 release from peripheral blood mononuclears cells (PBMC) from atopic asthma patients. Phytohaemagglutinin (PHA)-induced IL-13 release from PBMC was concentration-dependently inhibited by rolipram, a type 4 PDE inhibitor, as well as by dibutyryl cAMP, a membrane-permeant cAMP analogue. However, theophylline, a non-specific PDE inhibitor, and cilostazol, a type 3 PDE inhibitor, failed to inhibit IL-13 release. The inhibitory effect of rolipram was enhanced by the addition of forskolin (10(-4) m), an adenylyl cyclase stimulator. PHA itself did not alter the intracellular cAMP level. Rolipram concentration-dependently increased cAMP level in PHA-stimulated PBMC, and this increase was synergistically facilitated by the addition of forskolin (10(-4) m). These results suggest that type 4 PDE inhibitors, alone or synergistically in combination with forskolin, inhibit PHA-induced IL-13 release from PBMC of atopic asthma patients by elevating intracellular cAMP concentrations. These inhibitors have the potential to exert an anti-inflammatory effect by inhibiting IL-13 production in allergic diseases such as atopic asthma.
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PMID:Differential effect of phosphodiesterase inhibitors on IL-13 release from peripheral blood mononuclear cells. 1173 51

AWD 12-281 is a potent (IC(50) = 9.7 nM) and highly selective inhibitor of the phosphodiesterase 4 (PDE4) isoenzyme with low affinity to the high-affinity rolipram-binding site. The compound was optimized for topical treatment of asthma, chronic obstructive pulmonary disease (COPD), and allergic rhinitis. The aim of the present study was to assess the effect of AWD 12-281 in human inflammatory cells. Peripheral blood mononuclear cells (PBMCs), diluted whole blood, and human nasal polyp cells derived from surgically resected nasal polyps from patients with polyposis comprise sources of target tissue cells that can be used to predict anti-inflammatory effects in patients. AWD 12-281 was capable of suppressing the production of cytokines in stimulated PBMCs: interleukin-2 (IL-2, phytohemagglutinin stimulation), IL-5 (concanavalin A stimulation), IL-5 and IL-4 (anti-CD3/anti-CD28 costimulation), and lipopolysaccharide-stimulated release of tumor necrosis factor alpha (TNF alpha). The corresponding values for half-maximum inhibition, EC(50), for AWD 12-281 were within a narrow range (46-121 nM). Comparing the effect of AWD 12-281 with roflumilast, cilomilast (SB 207499), rolipram (RPR-73401), and 1-(3-nitrophenyl)-3-(4-pyridylmethyl)pyrido[2,3-d]pyrimidin-2,4(1H,3H)-dione (RS-25344-000), it could be shown that the PDE4 inhibitory activity was closely correlated with inhibitory potential as measured by the above-described assays. AWD 12-281 was also shown to suppress TNF alpha release in dispersed nasal polyps (EC(50) = 111 nM) and in diluted whole blood (EC(50) = 934 nM). The reduced activity in human blood may be related to high plasma protein binding. Currently, phase II clinical studies are under way to evaluate the therapeutic potential of AWD 12-281 in asthma, COPD, and allergic rhinitis.
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PMID:Anti-inflammatory potential of the selective phosphodiesterase 4 inhibitor N-(3,5-dichloro-pyrid-4-yl)-[1-(4-fluorobenzyl)-5-hydroxy-indole-3-yl]-glyoxylic acid amide (AWD 12-281), in human cell preparations. 1461 Feb 30

Roflumilast [APTA 2217, B9302-107, BY 217, BYK 20869] is a selective phosphodiesterase IV inhibitor. It is being developed by Altana Pharma (formerly Byk Gulden), a subsidiary of Altana Group, as an orally administered therapy for asthma, chronic obstructive pulmonary disease (COPD), allergic rhinitis and psoriasis. The drug is awaiting regulatory approval in Europe for the treatment of asthma and COPD. Byk Gulden has stated that roflumilast relieves asthma symptoms through both an anti-inflammatory effect and a muscle relaxant effect. Roflumilast has potential as first-line long-term therapy in mild-to-moderate COPD and as additive long-term therapy in moderate-to-severe COPD. Altana has stated that roflumilast is to be marketed under the brand name Daxas. Altana Group and Pharmacia Corporation (now Pfizer) signed an agreement on 22 April 2002 to collaborate on the development and commercialisation of roflumilast for the treatment of respiratory disorders, including asthma and COPD. The companies will jointly develop the drug for the US, Europe and other markets. Pharmacia will co-ordinate development in the US and Altana will co-ordinate development in Europe. After approval of the drug, Pharmacia and Altana will jointly launch and promote roflumilast in the US, Europe and elsewhere. Altana will receive an upfront payment and additional milestone payments. Altana additionally has the option to co-promote Pharmacia products in the US and elsewhere. On 16 April 2003, Pharmacia Corporation was acquired by, and merged into, Pfizer. In November 2002, Altana and Tanabe Seiyaku signed an agreement to collaborate on the development and commercialisation of roflumilast for the treatment of respiratory diseases, including asthma and COPD. Tanabe Seiyaku and Altana will develop roflumilast for asthma and COPD in Japan, and will jointly launch and co-promote roflumilast in Japan following regulatory approval. Roflumilast has been in multinational phase III clinical studies in Europe for the treatment of asthma and COPD. In September 2003, Altana announced the completion of a phase III trial in COPD in more than 1400 patients; the trial showed positive results. In the US, roflumilast is in phase III trials for the treatment of asthma and phase II trials for the treatment of COPD. Phase I clinical trials of roflumilast were begun in Japan by Tanabe Seiyaku in the fourth quarter of 2003. Altana has stated that roflumilast has shown significant superiority over placebo in the treatment of asthma in phase II trials. The efficacy of the drug appears to be comparable to low-dose inhaled corticosteroids in the treatment of asthma and at least equal to inhaled corticosteroids in the treatment of COPD. Altana Group presented data from phase II trials in 516 patients with COPD at an analyst meeting [August 2001, Bad Homburg, Germany] that showed that roflumilast 500 microg/day significantly improved FEV(1) at 24 weeks compared with placebo. In March 2004, Altana Pharma presented pharmacokinetic data from a phase I trial of roflumilast at the 60th Annual Meeting of the American Academy of Allergy, Asthma and Immunology (AAAAI-2004) [San Francisco, CA, USA]. This open-label, randomised, two-period crossover study investigated the pharmacokinetics of oral roflumilast and its active metabolite, roflumilast N-oxide, among 12 healthy male subjects. Participants received single doses of oral roflumilast 500 microg and intravenous (i.v) roflumilast 150 microg as a 15-min short-term infusion. In November 2002, the combined global market for asthma and COPD products was estimated to be worth >11 billion US dollars. In Japan, products in this market segment reached sales of approximately 1.5 billion US dollars in 2001. Roflumilast has patent protection in Europe and Japan until 2014 and in the US until 2015. The Financial Times in April 2002 claimed that roflumilast is an 'important' product for Altana, due to be listed on the New York Stock Exchange later in the same month. The Altana chairman confirmed that the company had been in talks with Pfizer, Bristol-Myers Squibb and Novartis with regard to future development and commercialisation of roflumilast. In September 2002, Dow Jones Newswires stated that Altana is to file for European approval of roflumilast 1 year later than initially was expected; however, this has not changed the company's outlook for the product, which was said to remain at at 1 billion Euros. In August 2001, the Financial Times reported that roflumilast, for the indication of smoker's cough alone, has the potential to reach sales of more than 500 million US dollars a year. A future co-marketing deal for roflumilast in the US was said to be "a key step towards expanding Altana's presence in the US".
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PMID:Roflumilast: APTA 2217, B9302-107, BY 217, BYK 20869. 1513 82

Allergic rhinitis and asthma share various clinical, pathophysiological and immunological characteristics and often coexist. Recent studies provide evidence of cross-talk between both airway compartments, possibly by systemic signalling. These observations resulted in the concept of 'allergic airway disease', providing a rationale for systemic treatment. Presently, many novel systemic treatment modalities, including anti-IgE and phosphodiesterase-4 (PDE4) inhibitors, are being evaluated in clinical trials. In the Netherlands, there are currently two registered systemic therapies targeting the pathophysiological mechanisms of the united airway disease: leukotriene receptor antagonists and immunotherapy. These therapies are usually prescribed in combination with the standard pharmacotherapy.
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PMID:[Allergic rhinitis and asthma: pathophysiological relationship and implications for treatment]. 1644 May 61


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