Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0030193 (pain)
 261,466 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cyclooxygenase (COX), first purified in 1976 and cloned in 1988, is the key enzyme in the synthesis of prostaglandins (PGs) from arachidonic acid. In 1991, several laboratories identified a product from a second gene with COX activity and called it COX-2. However, COX-2 was inducible, and the inducing stimuli included pro-inflammatory cytokines and growth factors, implying a role for COX-2 in both inflammation and control of cell growth. The two isoforms of COX are almost identical in structure but have important differences in substrate and inhibitor selectivity and in their intracellular locations. Protective PGs, which preserve the integrity of the stomach lining and maintain normal renal function in a compromised kidney, are synthesized by COX-1. In addition to the induction of COX-2 in inflammatory lesions, it is present constitutively in the brain and spinal cord, where it may be involved in nerve transmission, particularly that for pain and fever. PGs made by COX-2 are also important in ovulation and in the birth process. The discovery of COX-2 has made possible the design of drugs that reduce inflammation without removing the protective PGs in the stomach and kidney made by COX-1. These highly selective COX-2 inhibitors may not only be anti-inflammatory but may also be active in colon cancer and Alzheimer's disease.
 ...
PMID:Cyclooxygenases 1 and 2. 959 50

1. Non-steroidal antiinflammatory drugs (NSAIDs) are among the most frequently prescribed medications and are used primarily to control pain, stiffness, and reduce inflammation. 2. One of the most common adverse effects of NSAID therapy is gastrointestinal (GI) problems, specifically indigestion, nausea, dyspepsia, diarrhea, constipation, and gastritis. 3. Considerations in chronic pain management include non-pharmacologic treatment options (i.e., physical therapy, behavioral therapy, etc.), use of misoprostol for clients at high risk for NSAID induced GI problems, and monitoring blood and urine every 3 months to 1 year with chronic NSAID therapy to detect liver, kidney, and hematologic problems. 4. Current research is focused on development of a prostaglandin H synthetase (PGHS-2) inhibitor which should offer efficacy equal to the most potent NSAIDs with minimal side effects, including gastric safety.
 ...
PMID:Non-steroidal antiinflammatory drugs. A review. 965 39

The inducible form of cyclo-oxygenase (COX-2) mRNA is rapidly induced in the spinal cord following peripheral inflammation produced by intraplantar injection of Freund's complete adjuvant (FCA). COX-2 mRNA induction is also accompanied by increased prostaglandin (PG) levels which are closely correlated with behavioural indicators of increased pain sensitivity. The aim of this study was to determine whether the anti-inflammatory glucocorticoid, dexamethasone, which acts locally to prevent the development of oedema would also reduce the associated central changes characterised by the induction of COX-2 mRNA and PGs. Unilateral intraplantar FCA induced a marked oedema evident from 2 h to 7 days after FCA injection which was significantly attenuated by dexamethasone pretreatment at all time points. Dexamethasone also significantly prevented the induction of COX-2 mRNA (2 4 h) and elevated levels of prostaglandins (6-keto PGF1alpha) in lumbar spinal cord (8 h). In this study we have confirmed the anti-inflammatory effect of dexamethasone and linked this to central changes in gene expression relevant to the development of altered pain thresholds following intraplantar FCA.
 ...
PMID:Dexamethasone prevents the induction of COX-2 mRNA and prostaglandins in the lumbar spinal cord following intraplantar FCA in parallel with inhibition of oedema. 970 87

The enzymes cyclooxygenase-1 and cyclooxygenase-2 (COX-1 and COX-2) catalyze the conversion of arachidonic acid to prostaglandin (PG) H2, the precursor of PGs and thromboxane. These lipid mediators play important roles in inflammation and pain and in normal physiological functions. While there are abundant data indicating that the inducible isoform, COX-2, is important in inflammation and pain, the constitutively expressed isoform, COX-1, has also been suggested to play a role in inflammatory processes. To address the latter question pharmacologically, we used a highly selective COX-1 inhibitor, SC-560 (COX-1 IC50 = 0.009 microM; COX-2 IC50 = 6.3 microM). SC-560 inhibited COX-1-derived platelet thromboxane B2, gastric PGE2, and dermal PGE2 production, indicating that it was orally active, but did not inhibit COX-2-derived PGs in the lipopolysaccharide-induced rat air pouch. Therapeutic or prophylactic administration of SC-560 in the rat carrageenan footpad model did not affect acute inflammation or hyperalgesia at doses that markedly inhibited in vivo COX-1 activity. By contrast, celecoxib, a selective COX-2 inhibitor, was anti-inflammatory and analgesic in this model. Paradoxically, both SC-560 and celecoxib reduced paw PGs to equivalent levels. Increased levels of PGs were found in the cerebrospinal fluid after carrageenan injection and were markedly reduced by celecoxib, but were not affected by SC-560. These results suggest that, in addition to the role of peripherally produced PGs, there is a critical, centrally mediated neurological component to inflammatory pain that is mediated at least in part by COX-2.
 ...
PMID:Pharmacological analysis of cyclooxygenase-1 in inflammation. 978 85

Nimesulide is a selective COX-2 inhibitor used in a variety of inflammatory, pain and fever states. After healthy volunteers received oral nimesulide 100 mg in tablet, granule or suspension form the drug was rapidly and extensively absorbed. Mean peak concentrations (Cmax) of 2.86 to 6.50 mg/L were achieved within 1.22 to 2.75 hours of administration. The presence of food did not reduce either the rate or extent of nimesulide absorption. When nimesulide was administered in the suppository form, the Cmax was lower and occurred later than after oral administration; the bioavailability of nimesulide via suppository ranged from 54 to 64%, relative to that of orally administered formulations. Nimesulide is rapidly distributed and has an apparent volume of distribution ranging between 0.18 and 0.39 L/kg. It is extensively bound to albumin; the unbound fraction in plasma was 1%. The unbound fraction increased to 2 and 4% in patients with renal or hepatic insufficiency. With oral administration, the concentrations of nimesulide declined monoexponentially following Cmax. The estimated mean terminal elimination half-life varied from 1.80 to 4.73 hours. Excretion of the unchanged drug in urine and faeces is negligible. Nimesulide is largely eliminated via metabolic transformation and the principal metabolite is the 4'-hydroxy derivative (M1). Minor metabolites have been detected in urine and faeces, mainly in a conjugated form. Pharmacological tests in vivo have shown that the metabolites are endowed with anti-inflammatory and analgesic properties, although their activity is lower than that of nimesulide. Excretion in the urine and faeces accounted for 50.5 to 62.5% and 17.9 to 36.2% of an orally administered dose, respectively. The total plasma clearance of nimesulide, was 31.02 to 106.16 ml/h/kg, reflecting almost exclusive metabolic clearance. The drug has a low extraction ratio, close to 0.1. With twice daily oral or rectal administration of nimesulide, steady-state was achieved within 24 to 48 hours (2 to 4 administrations); only modest accumulation of nimesulide and M1 occurred. Gender has only a limited influence on the pharmacokinetic profiles of nimesulide and M1. The pharmacokinetic profiles of nimesulide and M1 in children and the elderly did not differ from that of healthy young individuals. Hepatic insufficiency affected the pharmacokinetics of nimesulide and M1 to a significant extent: the rate of elimination of nimesulide and M1 was remarkably reduced in comparison to the rate of elimination in healthy individuals. Therefore, a dose reduction (4 to 5 times) is required in patients with hepatic impairment. The pharmacokinetic profile of nimesulide and M1 was not altered in patients with moderate renal failure and no dose adjustment in patients with creatinine clearances higher than 1.8 L/h is envisaged. Pharmacokinetic interactions between nimesulide and other drugs given in combination [i.e. glibenclamide, cimetidine, antacids, furosemide (frusemide), theophylline, warfarin and digoxin] were absent, or of no apparent clinical relevance.
 ...
PMID:Clinical pharmacokinetics of nimesulide. 981 77

Nonsteroidal anti-inflammatory drugs (NSAIDs) produce their therapeutic activities through inhibition of cyclooxygenase (COX), the enzyme that makes prostaglandins (PGs). They share, to a greater or lesser degree, the same side effects, including gastric and renal toxicity. Recent research has shown that there are at least two COX isoenzymes. COX-1 is constitutive and makes PGs that protect the stomach and kidney from damage. COX-2 is induced by inflammatory stimuli, such as cytokines, and produces PGs that contribute to the pain and swelling of inflammation. Thus, selective COX-2 inhibitors should be anti-inflammatory without side effects on the kidney and stomach. Of course, selective COX-2 inhibitors may have other side effects and perhaps other therapeutic potential. For instance, COX-2 (and not COX-1) is thought to be involved in ovulation and in labor. In addition, the well-known protective action of aspirin on colon cancer may be through an action on COX-2, which is expressed in this disease. Moreover, NSAIDs delay the progress of Alzheimer's disease. Thus, selective COX-2 inhibitors may demonstrate new important therapeutic benefits as anticancer agents, as well as in preventing premature labor and perhaps even retarding the progression of Alzheimer's disease.
 ...
PMID:Anti-inflammatory drugs and their mechanism of action. 983 28

Cyclooxygenase (COX)-2 is the predominant COX isoform present at sites of inflammation, and produces prostaglandins (PG) that cause swelling and pain. However, in situations where the release of protective PGs by COX-1 has been lost, the induction of COX-2 may compensate and reduce inflammatory responses. This is particularly likely in large blood vessels, where, under physiological conditions, the release of prostacyclin by COX-1, present in the endothelium, is an important component of cardiovascular homeostasis. We, and others, have recently shown that COX-2 can be induced by proinflammatory cytokines in human blood vessels, and also in human airway cells. Moreover, recent data from our group have suggested that in these structures, COX-2 is anti-inflammatory at the level of cellular proliferation, adhesion receptor expression, and cytokine release.
 ...
PMID:Cyclooxygenase-2 as a therapeutic target. 983 29

Cyclooxygenase (COX)-2 was induced in an acute exudative inflammatory model (rat carrageenin-induced pleurisy) in which prostaglandin E2, 6-keto-prostaglandin F1alpha, and thromboxane B2 were generated in the pleural fluid. Selective COX-2 inhibitors, such as NS-398, inhibited the plasma exudation and generation of prostaglandin E2, but not that of thromboxane B2 and 6-keto-prostaglandin F1alpha, in the pleural fluid. In proliferative inflammatory models, COX-2 was induced, and selective COX-2 inhibitors suppressed granuloma formation, particularly, microvessel formation. COX-2 was induced during angiogenesis in a sponge model implanted into skin of rat, and the COX-2 inhibitor suppressed the angiogenesis. As induction of COX-2 was reported in osteoblasts, COX-2 was involved in most characteristic responses of acute exudative inflammation, granuloma formation, bone resorption, and pain in rheumatoid arthritis. The prevention of these COX-2 responses provides a rationale for the effectiveness of COX-2 inhibitors in the treatment of rheumatoid arthritis.
 ...
PMID:Possible background mechanisms of the effectiveness of cyclooxygenase-2 inhibitors in the treatment of rheumatoid arthritis. 983 32

Cyclooxygenases (COX) are prostaglandin synthases and are the main therapeutic targets for non-steroidal anti-inflammatory drugs. Recently it has been established that apart from the constitutive isoform, an inducible isoform of this enzyme is upregulated after injurious stimuli. The structures of the genes encoding these enzymes and protein structures have been determined, and with the utilization of knockout mice, the physiological properties of each isozyme are being revealed. COX-1 is responsible for the production of physiological levels of prostanoids, whereas COX-2 is upregulated during inflammatory states and produces prostanoids responsible for the generation of fever, pain or other inflammatory responses. Selective COX-2 blockers may be a safe and useful alternative in the treatment of inflammatory disorders, pain, and fever.
 ...
PMID:[Current topics in the regulation of prostanoids-1. Inducible cyclooxygenase COX-2 and selective blockers]. 985 96

Clinical trials with monoclonal antibodies directed against TNF alpha (anti-TNF mAbs) and soluble TNF receptor fusion proteins (sTNFR-IgGs) have demonstrated that systemic and synovial trapping of TNF alpha results in long lasting anti-inflammatory and anti-nociceptive effects in patients with rheumatoid arthritis. Clinical indices of inflammatory synovitis and laboratory parameters (CRP and ESR) respond to single and repeated administrations of anit-TNF alpha therapies in a dose-dependent fashion. Studies on the immuno-pharmacological profile in patients suggest evidence that TNF alpha trapping down-regulates the effector mechanisms involved in the immuno-inflammatory response in rheumatoid arthritis. Inhibition of PLA 2- and COX-2-derived pathways of mediators of inflammation (prostanoids and leukotrienes) decreases signs and symptoms of inflammatory synovitis such as joint swelling, tenderness and pain. Down-regulating of the cytokine-inducible adhesion molecules ICAM-1, VCAM-1 and ELAM-1 in endothelial cells and synoviocytes results in a marked inhibition of transendothelial migration of inflammatory and immune cells. A decrease of cytokine-regulated metalloproteinase expression results in normalization of circulating MMP-1 and MMP-3 levels. The effect of TNF alpha neutralization on mechanisms of rheumatoid joint destruction has the long-term potential for preventing or decreasing the rate of erosive changes of cartilage and bone.
 ...
PMID:[Immunopharmacologic profile and therapeutic prospects of anti-TNF-alpha therapy]. 986 33


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>