Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.4.1 (phosphodiesterase)
 18,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

One of the challenges in the therapy with anti-inflammatory drugs is the avoidance of gastrointestinal side effects, which may be achieved by selective inhibition of cyclooxygenase (COX) -2. CGP 28238 is reported with these characteristics inhibiting selectively the COX-2 activity at nanomolar concentrations. However, we report here on a novel action of this compound uncovered during the application of higher concentrations. In rat mesangial cells, CGP 28238 induced the mRNA and the protein of COX-2 as well as those of inducible nitric oxide synthase and soluble phospholipase A2. In the case of COX-2, this stimulation had no effect on the production of COX-2 metabolites because of the effective blockade of the enzyme. In contrast, the level of NO produced by the cells increased in a concentration-dependent manner from 1.2 to 12.5 nmol of nitrite/3 x 10(5) cells. Furthermore, in combination with low doses of IL-1 CGP 28238 superinduced the formation of nitrite. The observed effects were independent of the inhibition of prostaglandin formation, as suggested by the failure of the potent COX inhibitor diclofenac to cause similar effects. Furthermore, the activity and expression of enzymes downstream of the COX step, such as prostacyclin synthase, were unaffected by CGP 28238. The inductive action of CGP 28238 could be blocked by inhibitors for tyrosine kinases and protein kinase A, such as genistein and KT5720, respectively. The increase in intracellular cAMP concentration in rat mesangial cells and the inhibition by CGP 28238 of phosphodiesterase 4 activity with an IC50 value of 23 muM gave a rationale to explain the underlying mechanisms for the induction of the inflammatory response genes COX-2, soluble phospholipase A2 and inducible NO synthase in rat mesangial cells.
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PMID:On the induction of cyclooxygenase-2, inducible nitric oxide synthase and soluble phospholipase A2 in rat mesangial cells by a nonsteroidal anti-inflammatory drug: the role of cyclic AMP. 949 2

Primary pulmonary hypertension (PPH) is a rare but life-threatening disease. Median survival, from the time of diagnosis, is considered to be 2.8 years. However, therapeutic medical advances over the past 2 decades have resulted in significant improvements in quality of life and survival in patients with PPH. Because pulmonary vasoconstriction, endothelial cell proliferation, smooth muscle cell proliferation, and in situ thrombosis contribute to the development of this disease, treatment with vasodilators, anti-proliferative agents, and anticoagulants is recommended.Currently, oral administration of calcium channel antagonists and intravenous infusion of epoprostenol (prostacyclin) are established as treatment of PPH. Epoprostenol has vasoprotective effects including vasodilation, anti-platelet aggregation, and inhibition of smooth muscle cell proliferation. Interestingly, prostacyclin synthase deficiency in the lungs, and impaired prostacyclin production, have been linked to the development of pulmonary hypertension in this disease. As a result, continuous intravenous infusion of epoprostenol has become recognized as a therapeutic breakthrough that can improve hemodynamics and survival in patients with PPH. The dramatic success of long-term intravenous prostacyclin is now leading to the development of epoprostenol analogs using newer drug delivery systems (oral beraprost, aerosolized iloprost, and subcutaneous treprostinil). In addition, promising drugs including endothelin antagonists and type V phosphodiesterase inhibitors have recently been developed. Furthermore, gene therapy with endothelial nitric oxide synthase gene or prostacyclin synthase gene may hold great promise in the treatment of PPH. Finally, accurate evaluation of disease severity and the efficacy of vasodilator therapy are important in the management of patients with PPH. In addition to invasive assessment by cardiac catheterization, we recommend repeated measurements of plasma brain natriuretic peptide, serum uric acid, and the distance walked in 6 minutes. These noninvasive parameters may be helpful as part of the evaluation of treatment in patients with PPH and, in particular, as a guide to the selection and timing for alternative therapies.
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PMID:Drug therapy of primary pulmonary hypertension. 1504 20

The International Business Communications conference on 'Pulmonary Hypertension: New Understanding for Therapeutic Development' was held in San Diego, CA, USA. Approximately 100 basic scientists and clinicians from academia and industry participated in this highly interactive two-day symposium on pulmonary hypertension (PHT). Topics discussed included current clinical therapies and novel therapeutic strategies, e.g., nitric oxide, phosphodiesterase (PDE) inhibition, prostacyclin synthase expression, endothelin receptor antagonism and elastase inhibition.
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PMID:IBC's conference on pulmonary hypertension: new understanding for therapeutic development. 1599 1