选择性环氧化酶-2抑制剂与抗炎植物药研究概况

目的 介绍选择性环氧化酶（COX）-2抑制剂与抗炎植物药研究概况。方法 综合分析国内外相关文献资料。结果 与结论COX是前列腺素合成过程中一个重要的限速酶，选择性COX-2抑制剂的开发已成为不良反应小的非甾体抗炎药的重要发展方向，从抗炎植物药中筛选疗效好、不起反应小的抗炎新药也具有良好的前景。     

Drug switching patterns among patients with rheumatoid arthritis and osteoarthritis using COX-2 specific inhibitors and non-specific NSAIDs

PURPOSE: To compare RA and OA patients' time-to-switch after newly initiating treatment with three most commonly used non-specific (NS)-NSAIDs and two COX-2 inhibitors, celecoxib and rofecoxib. METHODS: Managed care enrollees newly prescribed celecoxib, rofecoxib, ibuprofen, naproxen or diclofenac were identified. Time to switch to a different NS-NSAID or COX-2 specific inhibitor was determined using time-to-event analysis and Cox proportional hazards models were used to estimate the odds ratio (OR) after controlling for potential confounders. RESULTS: The time to 25% of the cohort switching was longer for rofecoxib and celecoxib (159 and 205 days respectively) compared to the three NS-NSAIDs (49-78 days). Patients were at the highest risk of switching within the first 100 days of therapy. After adjusting for potential confounding factors, the OR for switching to another NS-NSAID or COX-2 specific inhibitor ranged from 1.74 to 2.35 for the three NS-NSAIDs compared to celecoxib (all comparisons, p < 0.01). Similar findings were obtained when comparing rofecoxib to each of the three NS-NSAIDS (all comparisons, p < 0.01). When COX-2 inhibitors combined were compared to NS-NSAIDS combined, the OR for switching was 1.53 (95% confidence interval = 1.42-1.65; p < 0.01) after adjusting for potential confounders. CONCLUSIONS: Patients on the COX-2 specific inhibitors (celecoxib and rofecoxib) were significantly less likely to switch their therapy than patients on NS-NSAIDS (ibuprofen, naproxen and diclofenac). These results suggest that COX-2 specific inhibitors may be a more effective treatment option when compared with NS-NSAIDs in usual clinical practice.     

Synthesis and effects on the COX-1 and COX-2 activity in human whole blood ex vivo of derivatives containing the [1]benzothienol-[3, 2-d]pyrimidin-4-one heterocyclic system

Methyl and phenyl derivatives containing the [1]Benzothieno [3, 2-d]pyrimidin-4-one system have been synthesized and tested as inhibitors of COX-1 and COX-2 activities in human whole blood (HWB) ex vivo; all compounds turned out to be weak inhibitors of COX-1 activity, as deduced from the TXB(2) (thromboxane B) generation; the acid phenyl derivative 11 b was an interesting inhibitor of COX-2 activity, as deduced from the PGE(2) (prostaglandine E) generation.     

Etodolac: An overview of a selective COX-2 inhibitor

Etodolac is a non-steroidal anti-inflammatory drug (NSAID) which has been shown to be effective in the treatment of rheumatoid arthritis and osteoarthritis and a selective COX-2 inhibitor in a wide range of clinically relevant assays in direct comparisons with other NSAIDs. Studies have shown etodolac to have no overall suppression of gastric or duodenal prostaglandins and endoscopic analysis with etodolac showed placebo level scores in comparison with ibuprofen, which showed inducement of gastro-intestinal (GI) side effects. This high degree of gastric tolerability was further demonstrated by microbleeding studies. The favourable GI tolerability profile of etodolac has been shown in long-term and large-scale trials and by routine clinical observation. In summary, etodolac is a well established selective COX-2 inhibitor that has been shown not to suppress gastric or duodenal prostaglandins, to have minimal hepatic or renal effects and to have favourable GI tolerability in comparison with ibuprofen.     

选择性环氧合酶-2抑制剂的研究现状及进展

非甾体抗炎药（NSAIDs）是临床上应用非常广泛的一类药物，但严重的不良反应使其应用受到很大限制。研究已经发现，NSAIDs对炎症的有效治疗源干其对环氧合酶-2（COX-2）的抑制作用。综述了选择性COX-2抑制剂作用的分子基础、构效关系及其目前研究开发的现状和最新进展。     

Update on cyclooxygenase inhibitors: has a third COX isoform entered the fray?

ABSTRACT

It has been more than 30 years since Sir John Vane first reported that the pharmacological actions of aspirin-like drugs could be explained by their ability to inhibit cyclooxygenase (COX). Since then, a second isoform of COX, named COX‐2, has been discovered and highly selective inhibitors of this isoform have been marketed. Most recently, a splice variant of COX‐1 mRNA, retaining intron 1, and given the names COX‐3, COX‐1b or COX‐1v, has been described.

Non‐selective NSAIDs such as ibuprofen and naproxen, which inhibit both COX‐1 and COX‐2, have proven highly effective and safe in the short-term management of acute pain. Highly selective COX‐2 inhibitors including celecoxib, rofecoxib, valdecoxib, lumiracoxib, and etoricoxib were developed with the hope of significantly reducing the serious gastrointestinal toxicities associated with chronic high‐dose NSAID use. While long-term studies demonstrated that rofecoxib and lumiracoxib reduced the incidence of GI perforations, ulcerations and bleeds by approximately 60% compared to non-selective NSAIDs, recent reports also demonstrated that the chronic use of rofecoxib and celecoxib in arthritis and colorectal polyp patients, and the short-term use of parecoxib and valdecoxib in patients who had undergone coronary artery bypass surgery, resulted in a significant increase in serious cardiovascular events, including myocardial infarction and stroke compared to naproxen or placebo.

COX‐3 mRNA has been isolated in many tissues including canine and human cerebral cortex, human aorta, and rodent cerebral endothelium, heart, kidney and neuronal tissues. In transfected insect cells, canine COX‐3 protein is expressed and was selectively inhibited by acetaminophen. However, in humans and rodents an acetaminophen sensitive COX‐3 protein is not expressed because the retention of intron‐1 adds 94 and 98 nucleotides to the COX‐3 mRNA structure respectively. Since the genetic code is a triplicate code (3 nucleotides to form one amino acid), the retention of the intron in both species results in a frame shift in the RNA message and the production of a truncated protein with a completely different amino acid sequence than COX‐1 or COX‐2 lacking acetaminophen sensitivity.

Advances made through a combination of basic molecular biological and pharmacological techniques, and well designed randomized controlled clinical trials have demonstrated that the apparent gastrointestinal advantage of selective COX‐2 inhibitors appears to be outweighed by their potential for cardiovascular toxicity and that acetaminophen's analgesic and antipyretic effects do not involve the inhibition of the COX-1 splice variant protein, putative COX‐3.     

COX-2 selective inhibitors: analysis of the renal effects

COX-2 selective inhibitors provide analgesia and blunt inflammation while also sparing the gastrointestinal tract from classic NSAID toxicity. Therapeutic effects are thought to result from inhibition of the inflammatory COX-2 isoform. Organ sparing is considered the result of preservation of homeostatic COX-1 enzyme function. Similar roles of the COX isoforms in the kidney would reduce NSAID-associated nephrotoxicity. However, human kidney tissue expresses COX-2 enzyme, suggesting a role for this isoform in maintenance of physiological renal processes. Available clinical data on the renal effects of COX-2 selective inhibitors in humans also demonstrate nephrotoxic potential.     

The impact of antihypertensive drug groups on urinary albumin excretion in a non-diabetic population

AIMS: Microalbuminuria (30-300 mg 24 h-1) is recognized to be independently associated with renal and cardiovascular risk. Antihypertensives may lower microalbuminuria. We questioned whether the use of different antihypertensive drug classes in general practice influences microalbuminuria as related to blood pressure in nondiabetic subjects. METHODS: To study this, we used the data from 6836 subjects of an on-going population based study, focused on the meaning of microalbuminuria (PREVEND). Odds ratios, adjusted for age, sex, blood pressure, cholesterol level, smoking and the use of other antihypertensive or cardiovascular drugs, were calculated to determine the association of drug groups with microalbuminuria. Influence of antihypertensives on the relation between blood pressure and (log) urinary albumin excretion was determined by comparing linear regression lines. RESULTS: Microalbuminuria was significantly associated with the use of dihydropyridine calcium channel blockers (odds ratio: 1.76 [1.22-2.54]), but not with other antihypertensive drug groups. The linear regression line of the relation between blood pressure and (log) urinary albumin excretion was significantly steeper (P = 0.0047) for users of calcium channel blockers, but not for other antihypertensives, compared with subjects using no antihypertensive. Users of a combination of renin-angiotensin system inhibitors and diuretics however, had a less steep regression line (P = 0.037). CONCLUSIONS: This study suggests a disadvantageous effect of dihydropyridine calcium channel blockers on microalbuminuria compared with other antihypertensive drug groups. Thus, if microalbuminuria is causally related to an increased risk for cardiovascular morbidity and mortality, dihydropyridines do not seem to be agents of choice to lower blood pressure. Furthermore, the combination of renin-angiotensin system inhibition and diuretics seems to act synergistically.     

Design,Synthesis, and Biological Evaluation of 1,5‐Diaryl‐1,2,4‐triazole Derivatives as Selective Cyclooxygenase‐2 Inhibitors

A series of 1,5‐diaryl‐1,2,4‐triazole derivatives were synthesized and evaluated as cyclooxygenase‐2 (COX‐2) inhibitors. The results of the preliminary biological assays in vivo showed that eight compounds 5b , 6b , 6c , 7c , 8b , 8d , 9c , and 9d have potent anti‐inflammatory activity (P < 0.01), while compounds 6b , 6c , and 9c exhibit marked potency. Compound 6c was then selected for further investigation. In the COX inhibition assay in vitro, compound 6c was identified as a potent and selective inhibitor of COX‐2 (COX‐2 IC₅₀ = 0.37 µM; SI = 0.018), being equipotent to celecoxib (COX‐2 IC₅₀ = 0.26 µM; SI = 0.015). In a rat carrageenan‐induced paw edema assay, 6c exhibited moderate anti‐inflammatory activity (35% inhibition of inflammation) at 2 h after administration of 15 mg/kg as an oral dose. A docking study also revealed that compound 6c binds in the active site of COX‐2 in a similar mode to that of the known selective COX‐2 inhibitor SC‐558.