Characterization of rofecoxib as a cyclooxygenase-2 isoform inhibitor and demonstration of analgesia in the dental pain model

Photocatalytic N-Alkylation of NH-Diaryl Sulfondiimines via Anti-Markovnikov Hydroamination with Styrenes

Sulfondiimines, which are isoelectronic with sulfones and sulfoximines, represent a neglected yet intriguing pharmacophore in the discovery program. Herein, we present a facile and mild photocatalytic anti-Markovnikov hydroamination of styrenes for the construction of N-alkylated sulfondiimines with primary, secondary, and tertiary alkyl substituents. A sulfondiimine-derived analogue of the marketed drug Vioxx was synthesized using this method as the key step.

An Insilico evaluation of phytocompounds from Albizia amara and Phyla nodiflora as cyclooxygenase-2 enzyme inhibitors

PURPOSE

The enzyme Cyclooxygenases (COX-1 and COX-2) catalyze the formation of prostaglandin, a mediator of the inflammatory pathway. Inflammation related pathological conditions may be alleviated by targeting the Cox enzymes.COX-2 inhibitors that are currently available in the market causes undesirable side effects. Our present study focuses on the in-silico inhibition of COX -2 enzyme by the phytocompounds from Albizia amara and Phyla nodiflora.

METHODS

The phytochemicals present in Albizia amara and Phyla nodiflora were analyzed for their COX-2 inhibition potential. Eight compounds from Albizia amara and eleven compounds from Phyla nodiflora obtained from GC-MS analysis was used for the current study. Molecular docking was performed using AutoDock vina. The crystal structure of COX-2 (PDB ID: 5IKR) was obtained from Protein data bank. PyMol was used to remove any solvent, organic and inorganic molecules. Energy minimization of the protein was carried out using SPDBV software. Geometrical optimizations of the ligands were performed using Avogadro software. Celecoxib was used as the positive control. ADMET properties of the compounds were analyzed using SwissADME and ProtoxII online servers. Molecular mechanics/generalized born surface area (MM/GBSA) calculations were performed to evaluate the binding efficiency. Molecular dynamics of the protein and protein-ligand complex was studied for about 100 ns using Desmond package of Schrodinger suite.

RESULTS

Among the eighteen compounds, Squalene present in both the plants showed a better binding energy of -7.7 kcal/mol, when compare to other phytocompounds present in the extract. The control celecoxib showed a binding energy of about - 9.4 kcal/mol. The toxicity and ADMET properties of squalene indicated that it is non-toxic and followed Lipinski's rule. Molecular Dynamics (MD) analysis showed that the binding of squalene to the enzyme was stable.

CONCLUSION

Squalene could potentially inhibit COX2 and o wing to its properties, squalene can be formulated in gels/creams and could be possibly used for external edema and inflammation.

Copper-Catalyzed Phosphorylation of 2,3-Allenoic Acids and Phosphine Oxide: Access to Phosphorylated Butenolides

We investigated a novel Cu-catalyzed annulation of 2,3-allenoic acids with diphenylphosphine oxide, leading to the formation of 4-phosphate butenolides in up to 88% yield. The formation of the C-P bond provides new avenues for the functionalization of different furan-2(5H)-ones, with favorable features such as suitable functional group tolerance and mild synthesis conditions.

Cox-2 inhibitors in mandibular third molar surgery

Pain control during and after any surgical procedure, is extremely essential for the comfort of patients. Pain killers used routinely act by inhibiting cyclooxygenase to control pain and inflammation. Cox-1 is constitutively expressed in most cell types, including platelets, whereas Cox-2 is absent from most healthy tissues but is induced by pro-inflammatory or proliferative stimuli. Cox-1 plays a role in the production of prostaglandins involved in protection of the gastric mucosal layer and thromboxanes (TX) in platelets. Cox-2 generally mediates elevations of prostaglandins associated with inflammation, pain, and pyresis. Nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin and ibuprofen are generally nonselective inhibitors of Coxs. This lack of selectivity has been linked to their propensity to cause gastrointestinal side effects. The new Cox-2 selective inhibitors, or coxibs, show the same anti-inflammatory, analgesic, and antipyretic effects as nonselective NSAIDs but are supposed to have reduced side-effect profiles. This study evaluates whether rofecoxib (50 mg) given one hour pre-operatively or the same drug given one hour post-operatively is more effective in controlling the pain and swelling in mandibular third molar surgery.

Do etoricoxib and indometacin have similar effects and safety for gouty arthritis? A meta-analysis of randomized controlled trials

Background

Gout, a common medical condition that causes pain, can be treated by painkillers and anti-inflammatories. Indometacin and etoricoxib are two such drugs. However, no synthesized evidence exists comparing etoricoxib with indometacin in treating patients with gout.

Methods

We searched PubMed, Embase, Ovid MEDLINE, Web of Science, ScienceDirect, and the Cochrane Library without restrictions on language or publication date for potential randomized clinical trials comparing etoricoxib with indometacin for gout. The meta-analysis was conducted using a random-effects model.

Results

Search results yielded 313 references from six electronic databases, four of which met the eligibility criteria. These four were randomized clinical trials, and they involved a total of 609 patients with gouty arthritis. No significant differences were observed in pain score change, tenderness, or swelling between etoricoxib and indometacin; the mean differences were −0.05 (95% CI, −0.21 to 0.10), −0.06 (95% CI, −0.18 to 0.05), and −0.04 (95% CI, −0.17 to 0.09). However, the pooled data revealed that significantly fewer overall adverse events occurred in the etoricoxib group (n=105, 33.5%) than in the indometacin group (n=130, 44.1%) and the risk ratio was 0.77 (95% CI, 0.62–0.94).

Conclusion

Our meta-analysis revealed that etoricoxib and indometacin have similar effects on pain relief. However, etoricoxib has a significantly lower risk of adverse events than does indometacin, especially digestive system-related adverse events.

Preemptive analgesia-related gene and protein expression in third molar surgeries under non steroidal anti-inflammatory drug protocols: A PROSPERO-registered systematic review of clinical studies

Background

This study aimed to review translational studies focusing on third molar removal surgeries through a systematic analytical approach.

Material and Methods

A PROSPERO-registered systematic review (CRD42017060455) was conducted following the PRISMA statement to summarize current knowledge on gene expression in third molar surgeries. A search was performed in PubMed’s Medline and Scopus databases, without date or language restrictions, using the logical expression {[(Third molar) OR (preemptive) OR (cyclooxygenase inhibitors) OR (acute inflammation) AND (gene expression)]}.

Results

All studies included in the analysis evaluated gene expression in a third molar extraction model, using the preemptive analgesia methodology in seven investigations. The sample analyzed was obtained from gingival tissue biopsy (n=4), blood (n=1), transudate (n=1) and gingival tissue biopsy/transudate (n=1). There were differences with respect to evaluated genes, drug protocol, sample studied, and method for evaluating gene expression.

Conclusions

Third molar surgeries were found to be associated with different COX-related gene expression patterns. Although inflammatory events following the surgical procedure are associated with COX isoforms, data from preemptive analgesia studies are scarce, especially from studies correlating gene expression and clinical parameters. In the future, from a clinical perspective, identifying the molecular targets of a drug based on individual gene expression may be helpful to delineate specific third molar, surgery-related, preemptive analgesia protocols.

Key words:Third molar, gene expression, preemptive analgesia, systematic review.

Non-invasive different modalities of treatment for temporomandibular disorders: review of literature

Temporomandibular disorders (TMDs) are diseases that affect the temporomandibular joint and supporting structures. The goal of treatment for TMDs is elimination or reduction of pain and return to normal temporomandibular joint function. Initial treatment for TMDs is non-invasive and conservative, not surgical. Oral and maxillofacial surgeons should fully understand and actively care about non-invasive treatments for TMDs. The purpose of this study is to review the validity and outcomes of non-invasive and surgical treatment modalities for TMDs.

Mechanisms of Phytonutrient Modulation of Cyclooxygenase-2 (COX-2) and Inflammation Related to Cancer

The link between chronic inflammation and cancer involves cytokines and mediators of inflammatory pathways. Cyclooxygenase-2 (COX-2), a key enzyme in fatty acid metabolism, is upregulated during both inflammation and cancer. COX-2 is induced by pro-inflammatory cytokines at the site of inflammation and enhanced COX-2-induced synthesis of prostaglandins stimulates cancer cell proliferation, promotes angiogenesis, inhibits apoptosis, and increases metastatic potential. As a result, COX-2 inhibitors are a subject of intense research interest toward potential clinical applications. Epidemiological studies highlight the potential benefits of diets rich in phytonutrients for cancer prevention. Plants contain numerous phytonutrient secondary metabolites shown to modulate COX-2. Studies have shown that these metabolites, some of which are used in traditional medicine, can reduce inflammation and carcinogenesis. This review describes the molecular mechanisms by which phytonutrients modulate inflammation, including studies of carotenoids, phenolic compounds, and fatty acids targeting various inflammation-related molecules and pathways associated with cancer. Examples of pathways include those of COX-2, mitogen-activated protein kinase kinase kinase, mitogen-activated protein kinase, pro-inflammatory cytokines, and transcription factors like nuclear factor kappa B. Such phytonutrient modulation of COX-2 and inflammation continue to be explored for applications in the prevention and treatment of cancer.

Pharmacokinetic and pharmacodynamic evaluation according to absorption differences in three formulations of ibuprofen

OBJECTIVE

Prostaglandin E₂ (PGE₂) synthesis is modulated by COX2. Changes in PGE₂ could be used to quantify the COX2 inhibition after ibuprofen administration. This study investigated the pharmacokinetic and pharmacodynamic relationships for COX2 inhibition according to three formulations of ibuprofen in healthy male subjects.

MATERIALS AND METHODS

A randomized, open-label, single-dose, three-treatment, six-sequence crossover study was performed in 36 healthy South Korean male volunteers. Enrolled subjects received the following three 200 mg ibuprofen formulations: ibuprofen arginine, solubilized ibuprofen capsule, and standard ibuprofen. Pharmacokinetic and pharmacodynamic blood samples were collected for 16 hours following treatment. For pharmacodynamic evaluations, lipopolysaccharide (LPS)-induced PGE₂ inhibition at each time point compared to predose was measured. Noncompartmental analysis was used for pharmacokinetic assessment, and time-weighted average inhibition (WAI) of PGE₂ was applied to the pharmacodynamic evaluation.

RESULTS

After a single oral dose of the ibuprofen formulations, the median times to maximum concentration were 0.42, 0.5, and 1.25 hours in ibuprofen arginine, solubilized ibuprofen capsule, and ibuprofen, respectively. The maximum observed plasma concentration was lower in ibuprofen, and the area under the plasma concentration-time curve was comparable among the three formulations. A significant difference was observed between fast-acting formulations and standard ibuprofen tablets for both maximum concentration and time taken to reach it. Individual formulations had an effect on PGE₂ WAI during the 8 hours following treatment, resulting in significantly lower WAI in standard ibuprofen: ibuprofen arginine 18.4%, solubilized ibuprofen capsule 18.4%, and standard ibuprofen 11.6%.

CONCLUSION

Rapid absorption and higher peak concentration were observed in ibuprofen arginine and the solubilized ibuprofen capsule. Additionally, fast-acting formulations had more predominant inhibitory activity on the COX2 enzyme.

Expression of two WFDC1/ps20 isoforms in prostate stromal cells induces paracrine apoptosis through regulation of PTGS2/COX-2

BACKGROUND

WFDC1/Prostate stromal 20 (ps20) is a small secreted protein highly expressed within the prostate stroma. WFDC1/ps20 expression is frequently downregulated or lost in prostate cancer (PCa) and ps20 has demonstrated growth-suppressive functions in numerous tumour model systems, although the mechanisms of this phenomenon are not understood.

METHODS

Ps20 was cloned and overexpressed in DU145, PC3, LNCaP and WPMY-1 cells. Cellular growth, cell cycle and apoptosis were characterised. WPMY-1 stromal cells expressing ps20 were characterised by transcriptome microarray and the function of WPMY-1 conditioned media on growth of PCa cell lines was assessed.

RESULTS

Prostrate stromal 20 expression enhanced the proliferation of LNCaP cells, whereas stromal WPMY-1 cells were inhibited and underwent increased apoptosis. Prostrate stromal 20-expressing WPMY-1 cells secrete a potently proapoptotic conditioned media. Prostrate stromal 20 overexpression upregulates expression of cyclooxygenase-2 (COX-2) in LNCaP and WPMY-1 cells, and induces expression of a growth-suppressive phenotype, which inhibits proliferation of PCa cells by ps20-expressing WPMY-1 conditioned media. This growth suppression was subsequently shown to be dependent on COX-2 function.

CONCLUSIONS

This work posits that expression of ps20 in the prostate stroma can regulate growth of epithelial and other tissues through the prostaglandin synthase pathway, and thereby restricts development and progression of neoplasms. This provides a rational for selective pressure against ps20 expression in tumour- associated stroma.

Copper catalyzed synthesis of unsymmetrical diaryl sulfones from an arenediazonium salt and sodium p-toluenesulfinate

Aryl sulfones have been synthesized by the reaction of sodium p-toluenesulfinate and arenediazonium salts using a CuI catalyzed homogeneous system.

A comparative study to evaluate the cardiovascular risk of selective and nonselective cyclooxygenase inhibitors (COX-Is) in arthritic patients

BACKGROUND

During the past 2 years, a great deal of evaluation has been accomplished on the cardiovascular (CV) effects of nonsteroidal anti-inflammatory drugs (NSAIDs), nonselective and selective cyclooxygenase-2 inhibitors (COX-2-Is). Clinical trial databases for nonselective and selective COX-2-Is have shown variable effects on CV risk. There is much controversy regarding the CV safety of these selective and nonselective COX inhibitors (COX-Is). This study was therefore conducted to assess and compare the CV risk of COX-Is in arthritic patients over a period of time.

METHODS

In this prospective comparative study, adult arthritics of either sex who were freshly diagnosed or taking COX-Is for <3 months were included. Patients were grouped into nonselective and selective COX-2-I groups with reference to the treatment they received, whereas arthritics with no history of COX-I treatment were included as controls. CV risk factors like blood pressure (BP), blood sugar level (BSL), lipid profile, and body mass index (BMI) were assessed and compared; the demography of CV risk factors was also studied. Data obtained were analyzed with Student's t-test using OpenEpi statistical software (Andrew G. Dean and Kevin M. Sullivan, Atlanta, GA, USA).

RESULTS

The study clearly revealed that all NSAIDs exhibit potential CV risk; however, selective COX-2-Is were found to exhibit more CV risk. BMI, BP and lipid profile, the potential CV risk factors, showed significant impairment in a selective COX-2-I group: p<0.01, p<0.001 and p<0.05, respectively, vs. baseline and p<0.05 for BMI and triglycerides vs. nonselective COX-Is.

CONCLUSIONS

This study depicts the impending CV risk of selective COX-2-Is and confirms and reevaluates the results of earlier studies in this regard.

A cohort study to evaluate cardiovascular risk of selective and nonselective cyclooxygenase inhibitors (COX-Is) in arthritic patients attending orthopedic department of a tertiary care hospital

Background:

Cyclooxygenase-2 inhibitors (COX-2-Is) have recently been concerned in the occurrence of adverse cardiovascular (CV) events. Rofecoxib and valdecoxib has been withdrawn from the market, but celecoxib, etoricoxib and parecoxib continues to be used. Other nonsteroidal anti-inflammatory drugs (NSAIDs) may also increase the risk of CV events. However, clinical trial databases for COX-2-Is had created lots of controversies regarding cardiovascular safety of selective and nonselective cyclooxygenase inhibitors (COX-Is). This study was, conducted to assess and compare the CV risk of COX-Is in arthritic patients over a period of time.

Materials and Methods:

In this prospective cohort study adult arthritics of either sex those were freshly diagnosed or taking COX-Is for < 3 months; were included. Patients were grouped into nonselective and selective COX-2-I groups with reference to treatment they received. The CV risk factors like blood pressure (BP), blood sugar level (BSL), lipid profile, body mass index (BMI) were assessed and compared; demography of CV risk factors was also studied. Data obtained was analysed using Student's ‘t’-test of OpenEpi statistical software.

Results:

Study clearly revealed that all NSAIDs exhibit variable CV risk; however, selective COX-2-Is found to exhibit more CV risk. BMI, BP and lipid profile; the potential CV risk factors, showed significant impairment in selective COX-2-Is group; P < 0.01, P < 0.001 and P < 0.05, respectively, compared to baseline and P < 0.05 vs. nonselective COX-Is for BMI.

Conclusions:

This study portrays the potential CV risk of selective COX-2-Is; confirms and re-evaluate the results of earlier studies in this regard.

Multi-dimensional target profiling of N,4-diaryl-1,3-thiazole-2-amines as potent inhibitors of eicosanoid metabolism

Eicosanoids like leukotrienes and prostaglandins play a considerable role in inflammation. Produced within the arachidonic acid (AA) cascade, these lipid mediators are involved in the pathogenesis of pain as well as acute and chronic inflammatory diseases like rheumatoid arthritis and asthma. With regard to the lipid cross-talk within the AA pathway, a promising approach for an effective anti-inflammatory therapy is the development of inhibitors targeting more than one enzyme of this cascade. Within this study, thirty N-4-diaryl-1,3-thiazole-2-amine based compounds with different substitution patterns were synthesized and tested in various cell-based assays to investigate their activity and selectivity profile concerning five key enzymes involved in eicosanoid metabolism (5-, 12-, 15-lipoxygenase (LO), cyclooxygenase-1 and -2 (COX-1/-2)). With compound 7, 2-(4-phenyl)thiazol-2-ylamino)phenol (ST-1355), a multi-target ligand targeting all tested enzymes is presented, whereas compound 9, 2-(4-(4-chlorophenyl)thiazol-2-ylamino)phenol (ST-1705), represents a potent and selective 5-LO and COX-2 inhibitor with an IC50 value of 0.9 ± 0.2 μM (5-LO) and a residual activity of 9.1 ± 1.1% at 10 μM (COX-2 product formation). The promising characteristics and the additional non-cytotoxic profile of both compounds reveal new lead structures for the treatment of eicosanoid-mediated diseases.

New satiety hormone nesfatin-1 protects gastric mucosa against stress-induced injury: mechanistic roles of prostaglandins, nitric oxide, sensory nerves and vanilloid receptors

Nesfatin-1 belongs to a family of anorexigenic peptides, which are responsible for satiety and are identified in the neurons and endocrine cells within the gut. These peptides have been implicated in the control of food intake; however, very little is known concerning its contribution to gastric secretion and gastric mucosal integrity. In this study the effects of nesfatin-1 on gastric secretion and gastric lesions induced in rats by 3.5h of water immersion and restraint stress (WRS) were determined. Exogenous nesfatin-1 (5-40μg/kg i.p.) significantly decreased gastric acid secretion and attenuated gastric lesions induced by WRS, and this was accompanied by a significant rise in plasma NUCB2/nefatin-1 levels, the gastric mucosal blood flow (GBF), luminal NO concentration, generation of PGE2 in the gastric mucosa, an overexpression of mRNA for NUBC2 and cNOS, as well as a suppression of iNOS and proinflammatory cytokine IL-1β and TNF-α mRNAs. Nesfatin-1-induced protection was attenuated by suppression of COX-1 and COX-2 activity, the inhibition of NOS with L-NNA, the deactivation of afferent nerves with neurotoxic doses of capsaicin, and the pretreatment with capsazepine to inhibit vanilloid VR1 receptors. This study shows for the first time that nesfatin-1 exerts a potent protective action in the stomach of rats exposed to WRS and these effects depend upon decrease in gastric secretion, hyperemia mediated by COX-PG and NOS-NO systems, the activation of vagal and sensory nerves and vanilloid receptors.

The efficacy of pre-operative oral medication of paracetamol, ibuprofen, and aceclofenac on the success of maxillary infiltration anesthesia in patients with irreversible pulpitis: A double-blind, randomized controlled clinical trial

AIM

To determine the effect of preoperative administration of paracetamol (PARA), ibuprofen (IBUP), or aceclofenac (ACEC) on the success of maxillary infiltration anesthesia in patients with irreversible pulpitis in a double-blinded randomized controlled trial.

MATERIALS AND METHODS

One hundred and twenty patients with irreversible pulpitis of a maxillary first molar participated. Patients indicated their pain scores on a Heft Parker visual analog scale, after which they were randomly divided into four groups (n = 30). The subjects received identical capsules containing 1000 mg PARA, 800 mg IBUP, 100 mg ACEC or cellulose powder (placebo, PLAC), 1 h before administration of maxillary infiltration anesthesia with 2% lidocaine containing 1:200,000 epinephrine. Access cavities were then prepared and success of anesthesia was defined as the absence of pain during access preparation and root canal instrumentation. The data were analyzed using chi-squared tests.

RESULTS

The success rates in descending order were 93.3% (IBUP), 90% (ACEC), 73.3% (PARA), and 26.5 % (PLAC). A significant (P < 0.001) difference was found between the drug groups and the PLAC group.

CONCLUSIONS

Pre-operative administration of PARA, IBUP, and ACEC significantly improved the efficacy of maxillary infiltration anesthesia in patients with irreversible pulpitis.

Efficacy and safety of additional 200-mg dose of celecoxib in adult patients with postoperative pain following extraction of impacted third mandibular molar: a multicenter, randomized, double-blind, placebo-controlled, phase II study in Japan

BACKGROUND

Although third mandibular molar extraction is a widely used and validated model of acute pain for evaluating analgesic efficacy, a large proportion of patients experience moderate or severe pain following this procedure and require analgesia. Current treatment options have been associated with safety concerns and alternative therapies are sought.

OBJECTIVE

Our aim was to assess the efficacy and safety of an additional 200-mg dose of celecoxib, administered 5 to 12 hours after an initial 400-mg dose of the drug for the treatment of moderate or severe acute pain following extraction of an impacted third mandibular molar.

METHODS

This was a multicenter, randomized, double-blind, placebo-controlled, Phase II study. Patients experiencing moderate or severe pain within 1 to 2 hours following extraction of an impacted third mandibular molar received an initial 400-mg dose of celecoxib. Patients requiring additional analgesia were subsequently randomized to receive either an additional 200-mg dose of celecoxib or placebo 5 to 12 hours after the initial dose. The study was designed and conducted by Pfizer Inc. for approval of celecoxib in Japan for the indication of acute pain. The primary end point was the patient's impression of efficacy (4-category global evaluation scale). Secondary efficacy end points included pain intensity on a 4-category pain intensity scale, pain intensity on a 100-mm visual analog scale (VAS), and the pain intensity difference (100-mm VAS). In an exploratory analysis, use of rescue medication was evaluated. Primary and secondary end points were analyzed using the full analysis set. Assessment of the safety profile included a physical examination, measurement of pulse rate and blood pressure, standard 12-lead ECG, and laboratory tests.

RESULTS

A total of 69 patients (celecoxib, 42/64 [65.6%]; placebo, 27/58 [46.6%]) received the additional dose of study medication; all completed the study without the need for rescue medication. A significantly higher proportion of patients in the celecoxib 200 mg group (41/64 [64.1%]) compared with the placebo group (15/58 [25.9%]) rated the study medication as "good" or "excellent" ≥ 2 hours after the additional dose (P < 0.0001). Pain intensity (VAS) 2 hours after the additional dose was significantly higher in the placebo group than in the celecoxib 200 mg group (P = 0.0003). The reduction in pain intensity from baseline to 2 hours after the additional dose of study medication was also significantly greater in the celecoxib 200 mg group than in the placebo group (P < 0.0001). The incidence of treatment-related, all-cause adverse events was slightly lower in patients receiving celecoxib 200 mg (20.3%) compared with placebo (31.0%).

CONCLUSIONS

Overall, an additional 200-mg dose of celecoxib was well tolerated and efficacious in reducing the pain associated with extraction of an impacted third mandibular molar in the study population. ClinicalTrials.gov identifier: NCT01062113.

Neuromodulatory role of endogenous interleukin-1β in acute seizures: possible contribution of cyclooxygenase-2

The function of endogenous interleukin-1β (IL-1β) signaling in acute seizure activity was examined using transgenic mice harboring targeted deletions in the genes for either IL-1β (Il1b) or its signaling receptor (Il1r1). Acute epileptic seizure activity was modeled using two mechanistically distinct chemoconvulsants, kainic acid (KA) and pentylenetetrazole (PTZ). KA-induced seizure activity was more severe in homozygous null (-/-) Il1b mice compared to their wild-type (+/+) littermate controls, as indicated by an increase in the incidence of sustained generalized convulsive seizure activity. In the PTZ seizure model, the incidence of acute convulsive seizures was increased in both Il1b and Il1r1-/- mice compared to their respective +/+ littermate controls. Interestingly, the selective cyclooxygenase (COX)-2 inhibitor, rofecoxib, mimicked the effect of IL-1β deficiency on PTZ-induced convulsions in Il1r1+/+ but not -/- mice. Together, these results suggest that endogenous IL-1β possesses anticonvulsive properties that may be mediated by arachidonic acid metabolites derived from the catalytic action of COX-2.

Natural anti-inflammatory agents for pain relief

The use of both over-the-counter and prescription nonsteroidal medications is frequently recommended in a typical neurosurgical practice. But persistent long-term use safety concerns must be considered when prescribing these medications for chronic and degenerative pain conditions. This article is a literature review of the biochemical pathways of inflammatory pain, the potentially serious side effects of nonsteroidal drugs and commonly used and clinically studied natural alternative anti-inflammatory supplements. Although nonsteroidal medications can be effective, herbs and dietary supplements may offer a safer, and often an effective, alternative treatment for pain relief, especially for long-term use.

Does administration of non-steroidal anti-inflammatory drug determine morphological changes in adrenal cortex: ultrastructural studies

Rofecoxib (Vioxx© made by Merck Sharp & Dohme, the USA) is a non-steroidal anti-inflammatory drug which belongs to the group of selective inhibitors of cyclooxygenasis-2, i.e., coxibs. Rofecoxib was first registered in the USA, in May 1999. Since then the drug was received by millions of patients. Drugs of this group were expected to exhibit increased therapeutic action. Additionally, there were expectations concerning possibilities of their application, at least as auxiliary drugs, in neoplastic therapy due to intensifying of apoptosis. In connection with the withdrawal of Vioxx© (rofecoxib) from pharmaceutical market, attempts were made to conduct electron-microscopic evaluation of cortical part of the adrenal gland in preparations obtained from animals under influence of the drug. Every morning animals from the experimental group (15 rats) received rofecoxib (suspension in physiological saline)--non-steroidal anti-inflammatory drug (Vioxx©, Merck Sharp and Dohme, the USA), through an intragastric tube in the dose of 1.25 mg during 8 weeks. In the evaluated material, there was found a greater number of secretory vacuoles and large, containing cholesterol and other lipids as well as generated glucocorticoids, lipid drops in cytoplasm containing prominent endoplasmic reticulum. There were also found cells with cytoplasm of smaller density--especially in apical and basal parts of cells. Mitochondria occasionally demonstrated features of delicate swelling. The observed changes, which occurred on cellular level with application of large doses of the drug, result from mobilization of adaptation mechanisms of the organism.

Rofecoxib, but not celecoxib, increases the risk of thromboembolic cardiovascular events in young adults-a nationwide registry-based study

PURPOSE

To examine the risk of thromboembolic cardiovascular events in users of coxibs and NSAIDs in a nationwide cohort.

METHODS

Data were synchronised from three nationwide databases, the Icelandic Medicines Registry (IMR), The Icelandic National Patient Registry (INPR) and the Registry for Causes of Death at Statistics Iceland (RCD), for prescriptions for NSAIDs or coxibs with respect to hospitalisation for unstable angina pectoris, myocardial infarction and cerebral infarction over a 3-year period. The Cox proportional hazards model and Poisson regression were used to analyse the data.

RESULTS

A total of 108,700 individuals received prescriptions for NSAIDs or coxibs (ATC code M01A), of whom 78,539 received one drug only (163,406 person-years). Among those receiving only one drug 426 individuals were discharged from hospital with endpoint diagnoses. In comparison to diclofenac, the incidence ratios, adjusted for age and gender, were significantly higher for cerebral infarction (2.13; 95% CI 1.54-2.97; P < 0.001), for myocardial infarction (1.77; 95% CI 1.34-2.32; P < 0.001) and for unstable angina pectoris (1.52; 95% CI 1.01-2.30; P = 0.047) for patients who used rofecoxib. For naproxen users, the incidence ratio was 1.46 for myocardial infarction (95% CI 1.03-2.07; P = 0.03), but was reduced in ibuprofen users (0.63; 95% CI 0.40-1.00; P = 0.05). The youngest users of rofecoxib (< or =39 years) had the highest hazard ratio (HR) for cardiovascular events (8.34; P < 0.001), while those > or =60 years had a lower but still significantly elevated HR (1.35; P = 0.001).

CONCLUSION

This Icelandic nationwide registry-based study amounting to 163,406 patient-years showed increased risk of cardiovascular events, i.e. cerebral infarction, myocardial infarction and unstable angina pectoris, among rofecoxib and naproxen users in comparison to diclofenac users. The added risk was most pronounced in young adults using rofecoxib.

Single dose oral rofecoxib for acute postoperative pain in adults

BACKGROUND

Editor's note: The anti-inflammatory drug rofecoxib (Vioxx) was withdrawn from the market at the end of September 2004 after it was shown that long-term use (greater than 18 months) could increase the risk of heart attack and stroke in a study of secondary prevention of adenoma recurrence. Further information is available at www.vioxx.com.Rofecoxib is a selective cyclooxygenase-2 (COX-2) inhibitor previously licensed for treating acute and chronic pain; it was associated with fewer gastrointestinal adverse events than conventional NSAIDs. An earlier Cochrane review (Barden 2005) showed that rofecoxib is at least as effective as conventional non-steroidal anti-inflammatory drugs (NSAIDs) for postoperative pain.

OBJECTIVES

To assess the analgesic efficacy and adverse effects of rofecoxib in single oral doses for moderate and severe postoperative pain.

SEARCH STRATEGY

We searched Cochrane CENTRAL, MEDLINE, EMBASE and the Oxford Pain Relief Database for studies to June 2009.

SELECTION CRITERIA

Randomised, double blind, placebo-controlled trials of single dose orally administered rofecoxib in adults with moderate to severe acute postoperative pain.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. Pain relief or pain intensity data were extracted and converted into the dichotomous outcome of number of participants with at least 50% pain relief over 4 to 6 hours, from which relative risk and number needed to treat to benefit (NNT) were calculated. Numbers of participants using rescue medication over specified time periods, and time to use of rescue medication, were sought as additional measures of efficacy. Information on adverse events and withdrawals was collected.

MAIN RESULTS

Twenty new studies and seven from the earlier review met the inclusion criteria. Twenty-four studies were in dental surgery and three in other types of surgery. In total, 2636 participants were treated with rofecoxib 50 mg, 20 with rofecoxib 500 mg, and 1251 with placebo. The NNT for at least 50% pain relief over 4 to 6 hours with rofecoxib 50 mg was 2.2 (2.0 to 2.3) in all studies combined, 1.9 (1.8 to 2.0) in dental studies, and 6.8 (4.6 to 13) in other types of surgery. The median time to use of rescue medication was 14 hours for rofecoxib 50 mg and 2 hours for placebo. Significantly fewer participants used rescue medication following rofecoxib 50 mg than with placebo. Adverse events did not differ from placebo.

AUTHORS' CONCLUSIONS

Rofecoxib 50 mg (two to four times the standard daily dose for chronic pain) is an effective single dose oral analgesic for acute postoperative pain in adults, with a relatively long duration of action.

Safety of Selective COX‐2 Inhibitors in Aspirin/Nonsteroidal Anti‐inflammatory Drug‐Intolerant Patients: Comparison of Nimesulide, Meloxicam, and Rofecoxib

BACKGROUND

Intolerance to acetylsalicylic acid (ASA) and other nonsteroidal anti-inflammatory drugs (NSAIDs) is a crucial problem in clinical practice. There is, therefore, a need for safer NSAIDs in patients with analgesic intolerance.

OBJECTIVE

To assess the safety of nimesulide, meloxicam, and rofecoxib, selective COX-2 inhibitors, in a group of ASA/NSAIDs-intolerant patients.

METHOD

Tolerances to nimesulide, meloxicam, and rofecoxib were assessed by single-blind placebo-controlled oral challenges. One hundred twenty-seven subjects with history of adverse reaction to ASA/NSAIDs received oral challenges with nimesulide, 61 subjects were challenged with meloxicam, 51 subjects were challenged with rofecoxib, and 37 subjects were challenged with all three drugs. Placebos were given to all patients on the first day of the study. On the second day, one-fourth and three-fourths of the therapeutic doses of the active drugs (nimesulide 100 mg, meloxicam 7.5 mg, or rofecoxib 25 mg) were given at 60-minute intervals. There was at least a 3-day interval between challenge tests. Erythema, pruritus accompanied by erythema, urticaria/angioedema, rhinorrhea, nasal obstruction, sneezing, dyspnea, or cough associated with a decrease of at least 20% in the forced expiratory volume (FEV1) and hypotension were considered as positive reactions.

RESULTS

Positive reactions to the nimesulide, meloxicam, and rofecoxib challenges were observed in 18/127 (14.3%), 5/61 (8.1%), and 1/51 (2.0%) patients, respectively. In each group of nine patients, there were two patients with asthma and four who developed skin type reactions and asthmatic reactions, respectively, to the nimesulide challenge. Among five patients who reacted to the meloxicam challenge, asthmatic type reactions were detected in two asthmatics. Only one urticarial type reaction was observed with rofecoxib challenge in one patient who presented with anaphylaxis to ASA/NSAIDs. All patients with asthma tolerated rofecoxib without any adverse effects. None of the patients reacted to the placebo. Among 37 patients challenged with all three drugs, 11 reacted to nimesulide, and one patient reacted only to meloxicam. Three patients reacted to more than one of the drugs tested, and one of them reacted to all drugs.

CONCLUSION

This is the first placebo-controlled report comparing these three drugs. The results indicate that among these alternative drugs for ASA/NSAIDs-intolerant patients, rofecoxib seems to have the most favorable tolerability.

Regulation of the apoptosis-inducing kinase DRAK2 by cyclooxygenase-2 in colorectal cancer

Background:

Cyclooxygenase-2 (COX-2) is over-expressed in colorectal cancer (CRC), rendering tumour cells resistant to apoptosis. Selective COX-2 inhibition is effective in CRC prevention, although having adverse cardiovascular effects, thus focus has shifted to downstream pathways.

Methods:

Microarray experiments identified genes regulated by COX-2 in HCA7 CRC cells. In vitro and in vivo regulation of DRAK2 (DAP kinase-related apoptosis-inducing kinase 2 or STK17β, an apoptosis-inducing kinase) by COX-2 was validated by qRT-PCR.

Results:

Inhibition of COX-2 induced apoptosis and enhanced DRAK2 expression in HCA7 cells (4.4-fold increase at 4 h by qRT-PCR, P=0.001), an effect prevented by co-administration of PGE₂. DRAK2 levels were suppressed in a panel of human colorectal tumours (n=10) compared to normal mucosa, and showed inverse correlation with COX-2 expression (R=−0.68, R²=0.46, P=0.03). Administration of the selective COX-2 inhibitor rofecoxib to patients with CRC (n=5) induced DRAK2 expression in tumours (2.5-fold increase, P=0.01). In vitro silencing of DRAK2 by RNAi enhanced CRC cell survival following COX-2 inhibitor treatment.

Conclusion:

DRAK2 is a serine–threonine kinase implicated in the regulation of apoptosis and is negatively regulated by COX-2 in vitro and in vivo, suggesting a novel mechanism for the effect of COX-2 on cancer cell survival.

Single dose oral ibuprofen for acute postoperative pain in adults

BACKGROUND

This review updates a 1999 Cochrane review showing that ibuprofen at various doses was effective in postoperative pain in single dose studies designed to demonstrate analgesic efficacy. New studies have since been published. Ibuprofen is one of the most widely used non-steroidal anti-inflammatory (NSAID) analgesics both by prescription and as an over-the-counter medicine. Ibuprofen is used for acute and chronic painful conditions.

OBJECTIVES

To assess analgesic efficacy of ibuprofen in single oral doses for moderate and severe postoperative pain in adults.

SEARCH STRATEGY

We searched Cochrane CENTRAL, MEDLINE, EMBASE and the Oxford Pain Relief Database for studies to May 2009.

SELECTION CRITERIA

Randomised, double blind, placebo-controlled trials of single dose orally administered ibuprofen (any formulation) in adults with moderate to severe acute postoperative pain.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. Pain relief or pain intensity data were extracted and converted into the dichotomous outcome of number of participants with at least 50% pain relief over 4 to 6 hours, from which relative risk and number-needed-to-treat-to-benefit (NNT) were calculated. Numbers of participants using rescue medication over specified time periods, and time to use of rescue medication, were sought as additional measures of efficacy. Information on adverse events and withdrawals were collected.

MAIN RESULTS

Seventy-two studies compared ibuprofen and placebo (9186 participants). Studies were predominantly of high reporting quality, and the bulk of the information concerned ibuprofen 200 mg and 400 mg. For at least 50% pain relief compared with placebo the NNT for ibuprofen 200 mg (2690 participants) was 2.7 (2.5 to 3.0) and for ibuprofen 400 mg (6475 participants) it was 2.5 (2.4 to 2.6). The proportion with at least 50% pain relief was 46% with 200 mg and 54% with 400 mg. Remedication within 6 hours was less frequent with higher doses, with 48% remedicating with 200 mg and 42% with 400 mg. The median time to remedication was 4.7 hours with 200 mg and 5.4 hours with 400 mg. Sensitivity analysis indicated that pain model and ibuprofen formulation may both affect the result, with dental impaction models and soluble ibuprofen salts producing better efficacy estimates. Adverse events were uncommon, and not different from placebo.

AUTHORS' CONCLUSIONS

The very substantial amount of high quality evidence demonstrates that ibuprofen is an effective analgesic in treating postoperative pain. NNTs for 200 mg and 400 mg ibuprofen did not change significantly from the previous review even when a substantial amount of new information was added. New information is provided on remedication.

Cyclooxygenase as a target for chemoprevention in colorectal cancer: lost cause or a concept coming of age?

COX-2 is upregulated at an early stage in colorectal carcinogenesis and generates prostaglandins, which promote cancer cell proliferation, impair apoptosis and enhance angiogenesis, promoting tumour growth and metastasis. There are ample data from animal models and human studies to demonstrate enhanced tumour progression associated with COX-2 activity in cancer cells. Conversely, NSAIDs including aspirin inhibit COX-2 and, therefore, have anti-neoplastic properties. There has been sustained interest in COX-2 as a chemopreventive target in colorectal cancer (CRC) and although both aspirin and COX-2 selective NSAIDs have demonstrated efficacy, adverse effects have limited their widespread adoption. In particular, evidence of the cardiovascular effects of COX-2 selective inhibitors has led to questioning of the suitability of COX-2 as a target for chemoprevention. This review examines the basis for targeting COX-2 in CRC chemoprevention, evaluates the efficacy and safety of the approach and examines future strategies in this area.

Experimental Study of COX-2 Selective and Traditional Non-steroidal Anti-inflammatory Drugs in Total Hip Replacement

This study investigated the effects of non-steroidal anti-inflammatory drugs (NSAIDs) on peri-operative blood loss during elective total hip replacement. Patients were randomized to receive enteric-coated diclofenac 50 mg ( n = 18), rofecoxib 12.5 mg ( n = 17) or placebo ( n = 16) administered orally three times daily for 2 weeks prior to surgery. Severe adverse effects resulting in discontinuation of trial participation occurred in six patients in the diclofenac group, five patients in the rofecoxib group and two patients in the placebo group; all drop-outs occurred at various times after surgery. Compared with placebo, peri-operative blood loss increased by 32% in the diclofenac group and by 7% in the rofecoxib group. Total mean ± SD blood loss was 1040 ± 136 ml in the diclofenac group, 844 ± 83 ml in the rofecoxib group and 789 ± 82 ml in the placebo group. Thus, administering a non-selective NSAID 2 weeks prior to elective total hip replacement significantly increases peri-operative blood loss.

Comparative inhibitory activity of etoricoxib, celecoxib, and diclofenac on COX-2 versus COX-1 in healthy subjects

We determined cyclo-oxygenase-1 and cyclo-oxygenase-2 inhibition in healthy middle-aged subjects (41-65 years) randomly assigned to four 7-day treatment sequences of etoricoxib 90 mg every day, celecoxib 200 mg twice a day, diclofenac 75 mg twice a day, or placebo in a double-blind, randomized, 4-period crossover study. Maximum inhibition of thromboxane B(2) (cyclo-oxygenase-1 activity) in clotting whole blood on day 7 (0-24 hours postdose) was the primary endpoint. Inhibition of lipopolysaccharide-induced prostaglandin E(2) in whole blood (cyclo-oxygenase-2 activity) was assessed on day 7 (0-24 hours postdose) as a secondary endpoint. Diclofenac had significantly greater maximum inhibition of thromboxane B(2) versus each comparator (P < .001); placebo 2.4% (95% confidence interval: -8.7% to 12.3%), diclofenac 92.2% (91.4% to 92.9%), etoricoxib 15.5% (6.6% to 23.5%), and celecoxib 20.2% (11.5% to 28.1%). Prostaglandin E(2) synthesis was inhibited with a rank order of potency of diclofenac > etoricoxib > celecoxib. In summary, at doses commonly used in rheumatoid arthritis, diclofenac significantly inhibits both cyclo-oxygenase-1 and cyclo-oxygenase-2, whereas etoricoxib and celecoxib significantly inhibit cyclo-oxygenase-2 and do not substantially inhibit cyclo-oxygenase-1.

Gastroprotective action of orexin-A against stress-induced gastric damage is mediated by endogenous prostaglandins, sensory afferent neuropeptides and nitric oxide

Orexin-A, identified in the neurons and endocrine cells in the gut, has been implicated in control of food intake and sleep behavior but little is known about its influence on gastric secretion and mucosal integrity. The effects of orexin-A on gastric secretion and gastric lesions induced in rats by 3.5 h of water immersion and restraint stress (WRS) or 75% ethanol were determined. Orexin-A (5-80 microg/kg i.p.) increased gastric acid secretion and attenuated gastric lesions induced by WRS and this was accompanied by the significant rise in plasma orexin-A, CGRP and gastrin levels, the gastric mucosal blood flow (GBF), luminal NO concentration and an increase in mRNA for CGRP and overexpression of COX-2 protein and the generation of PGE(2) in the gastric mucosa. Orexin-A-induced protection was abolished by selective OX-1 receptor antagonist, vagotomy and attenuated by suppression of COX-1 and COX-2, deactivation of afferent nerves with neurotoxic dose of capsaicin, pretreatment with CCK(2)/gastrin antagonist, CGRP(8-37) or capsazepine and by inhibition of NOS with L-NNA. This study shows for the first time that orexin-A exerts a potent protective action on the stomach of rats exposed to non-topical ulcerogens such as WRS or topical noxious agents such as ethanol and these effects depend upon hyperemia mediated by COX-PG and NOS-NO systems, activation of vagal nerves and sensory neuropeptides such as CGRP released from sensory nerves probably triggered by an increase in gastric acid secretion induced by this peptide.

Rofecoxib has Different Effects on Chemokine Production in Colorectal Cancer Cells and Tumor Immune Splenocytes

Cyclooxygenase-2 (COX-2) is overexpressed in colon tumors. Its main product is the immunosuppressive prostaglandin PGE2 that aids tumor immune escape. In this study, we analyzed mechanisms of action of the COX-2 inhibitor rofecoxib on the immune response to colorectal cancer in an animal model. The murine colorectal cancer cell line MC26, and splenocytes from BALB/c mice immune to irradiated MC26 cells, were incubated with rofecoxib or PGE2. In MC26 cells, 100 nM rofecoxib caused a complete abrogation of PGE2 production and inhibited cell proliferation. Splenocytes from tumor immune mice showed a 300% (P<0.01) increase in proliferation in response to irradiated MC26 cells, amplified to 450% (P<0.01) by 1 microM rofecoxib (n=3). MC26 cells incubated with 1 microM rofecoxib showed increased gene expression of CCL3, CCL5, and CCL20 (P<0.01). enzyme-linked immunosorbent assay tests also showed increased production of CCL5 and CCL20 (P<0.01). PGE2 reversed this effect causing a 40% reduction in chemokine gene expression (n=3). In contrast, splenocytes from naive BALB/c mice stimulated with irradiated MC26 cells had only a marginal chemokine response to rofecoxib. PGE2 caused a 50% down-regulation of CCL5 and CCL20 at the gene level (n=2) and 30% and 40% reduction of CCL3, CCL4, CCL5, and CCL20 at the protein level (n=2). Hence rofecoxib has a 2-fold effect upon the immune response to MC26 cells, by enhancing production of chemokines chemotactic for dendritic cells and also reducing PGE2-mediated inhibition of lymphoproliferation. Together, these may be sufficient for an effective TH1-mediated antitumor response. Rofecoxib may have potential as an addition to existing immunotherapy strategies.

A critical appraisal of COX-2 selective inhibition and analgesia: how good so far?

The development of COX-2 selective inhibitors has opened a new era of clinical investigation in NSAIDs. Discussion of the established concepts of inflammation and therapeutical uses of these drugs has changed the rationale for its clinical use and therapeutic labeling of these drugs. A comprehensive discussion across basic science and clinical areas involved in each of these concepts is presented. This led to a remarkable re-evaluation of our insights on their traditionally proposed mechanisms of analgesia, their side-effects, and the clinical indication of NSAIDs as "over the counter" pain killers. This may shift physicians toward a more rational use of this drug class.

Pharmacokinetic evaluation of rofecoxib : comparison of tablet and suspension formulations

OBJECTIVE

Rofecoxib suspension is a formulation developed to increase the convenience of rofecoxib therapy for patients who have difficulty swallowing tablets. This open-label, two-part study compared the single-dose pharmacokinetics of rofecoxib tablets and rofecoxib suspension in healthy subjects.

DESIGN AND STUDY PARTICIPANTS

Part I was a two-period crossover study that assessed the bioequivalence of the 12.5mg/5mL rofecoxib suspension and the 12.5mg rofecoxib tablet in 24 healthy subjects (12 men and 12 women). Part II was a crossover study in 24 additional healthy subjects (12 men and 12 women) that determined the bioequivalence of the rofecoxib 25mg/5mL suspension and the 25mg rofecoxib tablet.

RESULTS

No clinically meaningful differences between rofecoxib tablet and suspension were apparent with respect to the rofecoxib area under the concentration-time curve from time zero to infinity (AUC(0-infinity)) and maximum plasma concentration (C(max)), the primary measures of bioequivalence. At the 12.5mg and 25mg doses, the 90% CI for the geometric mean ratio (suspension/tablet) of both AUC(0-infinity) and C(max) fell within the prespecified interval for bioequivalence (0.80-1.25).

CONCLUSIONS

The rofecoxib suspension is bioequivalent to the rofecoxib tablet at single oral doses of 12.5mg and 25mg in healthy volunteers. The convenience and ease of administration of rofecoxib suspension may translate into increased compliance with therapy compared with a conventional solid tablet formulation, particularly for elderly patients.

A randomized, double-blind, celecoxib- and placebo-controlled study of the effectiveness of CS-706 in acute postoperative dental pain

BACKGROUND

CS-706 is a cyclooxygenase-2 (COX-2)-selective inhibitor with an in vitro selectivity ratio (COX-1:COX-2) similar to that of celecoxib. It has exhibited analgesic, anti-inflammatory, and antitumor properties in animal models.

OBJECTIVES

This study evaluated the tolerability of single doses of CS-706 and compared the analgesic efficacy of CS-706 with that of celecoxib and placebo in the dental pain model.

METHODS

This was a randomized, double-blind, double-dummy, active- and placebo-controlled study. Healthy male and female subjects with moderate to severe pain intensity (PI) after dental surgery were randomized ( approximately 50 per group) to receive a single oral dose of CS-706 10, 50, 100, or 200 mg; celecoxib 400 mg; or placebo. PI and pain relief (PR) were measured on categorical and visual analog scales through 24 hours after the dose. The primary efficacy variable was the time-weighted sum of PR scores at 4 hours after the dose (TOPAR4). The onset of analgesia was assessed by calculating the pain intensity difference (PID). Perceptible and meaningful pain relief were assessed using a 2-stopwatch method.

RESULTS

The majority of subjects were female (62.0%) and white (59.5%). Subjects' mean (SD) age was 22.6 (3.9) years, and their mean body mass index was 25.3 (5.1) kg/m(2). All doses of CS-706 were associated with significant analgesic efficacy compared with placebo based on the primary end point, TOPAR4 (P<0.001), and on all secondary end points (P<0.05, comparisons of all CS-706 doses vs placebo) with the exception of time to 100% PR for CS-706 10 mg. Single 50-, 100-, and 200-mg doses of CS-706 also were significantly more effective than celecoxib for TOPAR4 (P=0.036, P=0.004, and P=0.006, respectively). The onset of analgesia (PID >or= 1) for all CS-706 doses occurred within 1 hour after dosing (P<0.001 vs placebo). The median duration of analgesia, measured as the time to administration of rescue medication, was significantly greater for all doses of CS-706 compared with placebo (5.7 hours for CS-706 10 mg, >24 hours for CS-706 50, 100, and 200 mg, and 1.7 hours for placebo; P<0.001 for CS-706 50, 100, and 200 mg). These data suggest that once-daily administration of CS-706 may be effective in providing relief of acute pain. The incidence of adverse events was similar among all treatment groups. Adverse events occurring in >or= 5 % of subjects in any treatment group were nausea, vomiting, dry socket, dizziness, headache, and paresthesia.

CONCLUSION

Single doses of CS-706 had significant analgesic efficacy compared with celecoxib and placebo in the relief of postoperative dental pain in the healthy subjects enrolled in this study.

The efficacy of rofecoxib 50 mg and hydrocodone/acetaminophen 7.5/750 mg in patients with post-arthroscopic pain

OBJECTIVE

To compare the efficacy and tolerability of rofecoxib, hydrocodone/acetaminophen 7.5 mg/750 mg (H/A) and placebo in treating pain after arthroscopy of the knee.

METHODS

A randomized, double-blind, placebo-controlled, single dose study enrolling patients experiencing moderate or severe pain after knee arthroscopy. Patients with moderate-to-severe postoperative pain received either rofecoxib 50 mg (n = 151), H/A (n = 145), or placebo (n = 147). Pain was measured over 24 h. The primary endpoint was total pain relief at 6 h for rofecoxib 50 mg compared with placebo.

RESULTS

H/A (p = 0.003), but not rofecoxib (p = 0.256) was significantly more effective than placebo for total pain relief at 6 h (TOPAR6). Although analgesic onset and peak were significantly better for H/A than for both rofecoxib (p < 0.01, p < 0.05, respectively) and placebo (p < 0.05, p < 0.001, respectively), rofecoxib patients used significantly less rescue analgesia (p < 0.001) over 24 h. Rofecoxib also provided better Brief Pain Inventory Severity (p = 0.008) and Interference Domain (p = 0.045) scores at 24 h compared to placebo and had lower 24-h Pain Severity scores than H/A (p < 0.05). Treatments were generally well tolerated, with no significant difference in the frequency of patient-reported adverse events between groups.

CONCLUSIONS

Rofecoxib 50 mg did not provide significantly different pain relief than placebo at 6 h, and the primary endpoint TOPAR was not attained, although it did show several efficacy benefits at 24 h, including a significant opioid-sparing effect. All treatments were well tolerated, with no significant differences observed. The limited efficacy of rofecoxib in this study contrasts to the results of previous surgical studies evaluating rofecoxib, and may be partially explained by the postoperative dosing in this arthroscopic surgical model.

Natural antiinflammatory agents for pain relief in athletes

Most athletes experience musculoskeletal injuries during their sports activity that require rest at a minimum, and occasionally injuries are severe enough to necessitate surgical repair. Neurosurgeons are often consulted for athletically sustained injuries and prescribe medications for the associated pain. The use of both over-the-counter and prescription nonsteroidal medications is frequently recommended, but recent safety concerns must now be considered. The authors discuss the biochemical pathways of nonsteroidal drugs and review the potentially serious side effects of these medications. They also review the use of natural supplements, which may be a safer, and often as effective, alternative treatment for pain relief.

Prostaglandin/cyclooxygenase pathway in ghrelin-induced gastroprotection against ischemia-reperfusion injury

Ghrelin is involved in the control of food intake, but its role in gastroprotection against the formation of gastric mucosal injury has been little elucidated. We studied the effects of peripheral (i.p.) and central (i.c.v.) administration of ghrelin on gastric secretion and gastric mucosal lesions induced by 3 h of ischemia/reperfusion (I/R) with or without inhibition of ghrelin growth hormone secretagogue type 1a receptor (GHS-R1a) by using ghrelin antagonist, d-Lys(3)-GHRP-6; blockade of cyclooxygenase (COX)-1 (indomethacin, SC560 [5-(4-chlorophenyl)-1-(4-methoxyphenyl)-3-trifluoromethylpyrazole]) and COX-2 (rofecoxib); and bilateral vagotomy or capsaicin denervation. I/R produced typical gastric erosions, a significant fall in the gastric blood flow (GBF), an increase in gastric myeloperoxidase (MPO) activity and malonyldialdehyde (MDA) content, and the up-regulation of mucosal ghrelin mRNA. Ghrelin dose-dependently increased gastric acid secretion and significantly reduced I/R-induced gastric erosions, while producing a significant rise in the GBF and mucosal PGE(2) generation and a significant fall in MPO activity and MDA content. The protective and hyperemic activities of ghrelin were significantly attenuated in rats pretreated with d-Lys(3)-GHRP-6 and capsaicin denervation and completely abolished by vagotomy. Indomethacin, SC560, and rofecoxib, selective COX-1 and COX-2 inhibitors, attenuated ghrelin-induced protection that was restored by supplying the methyl analog of prostaglandin (PG) E(2). The expression of mRNA for COX-1 was unaffected by ghrelin, but COX-2 mRNA and COX-2 protein were detectable in I/R injured mucosa and further up-regulated by exogenous ghrelin. We conclude that ghrelin exhibits gastroprotective and hyperemic activities against I/R-induced erosions, the effects that are mediated by hormone activation of GHS-R1a receptors, COX-PG system, and vagal-sensory nerves.

Ibuprofen as a pre-emptive analgesic is as effective as rofecoxib for mandibular third molar surgery

The objective of this study was to compare the pre-emptive analgesic effect of rofecoxib, a cyclooxygenase (COX)-2 inhibitor, with a more traditional and commonly used analgesic, ibuprofen, for mandibular third molar surgery, utilizing a prospective, randomized, double-blind, placebo-controlled clinical trial. Fifty-five healthy patients who were scheduled to undergo surgical removal of an impacted mandibular third molar as outpatients at one of two government dental clinics in Fiji were enrolled. The patients were divided randomly into three groups to receive 50 mg rofecoxib or 400 mg ibuprofen, or a placebo 1 h prior to surgery. A dose of 1000 mg paracetamol was offered as rescue medication. Participants recorded their pain intensity on a 10-cm visual analogue scale 1 h before and just prior to surgery and every 30 min for 6 h following surgery. There were no significant analgesic differences between rofecoxib and ibuprofen at any time intervals postoperatively. Ibuprofen was significantly better at reducing pain at all time intervals by comparison with the placebo. Rofecoxib provided significantly better pain relief compared with the placebo, except at 60, 180, and 240 min postoperatively. Rescue medication use was significantly lower in the rofecoxib and ibuprofen groups by comparison with the placebo group; however, there was no significant difference between the two therapeutic groups. Rescue medication was used by 50%, 25%, and 94% of patients receiving rofecoxib, ibuprofen, and placebo, respectively. Ibuprofen, a commonly used over-the-counter analgesic, is as effective as rofecoxib for the relief of acute postoperative pain following third molar surgery when used pre-emptively.

Analgesic efficacy of the cyclooxygenase-inhibiting nitric oxide donor AZD3582 in postoperative dental pain: Comparison with naproxen and rofecoxib in two randomized, double-blind, placebo-controlled studies

OBJECTIVE

This study assessed the analgesic efficacy of single doses of 4-(nitrooxy)butyl-(2S)-2-(6-methoxy-2-naphthyl) propanoate (AZD3582) in acute postoperative dental pain after the removal of an impacted mandibular third molar (ie, wisdom tooth).

METHODS

Two randomized, placebo-controlled, double-blind studies were performed. In a dose-finding study, 242 patients were randomized to AZD3582 375, 750, 1500, or 2250 mg (n = 41, 37, 42, and 41, respectively); naproxen 500 mg (n = 39); or placebo (n = 42). In a comparator study, 282 patients were randomized to AZD3582 500 mg (n = 78) or 750 mg (n = 83), rofecoxib 50 mg (n = 80), or placebo (n = 41). Primary outcomes included time to rescue medication, time to pain relief, and mean pain intensity difference (MPID), as well as safety profile. Pain was rated on a visual analog scale.

RESULTS

In the dose-finding study, 52% (126/242) were women; the mean (SD) age was 25.1 (4) years, mean weight was 69.0 kg, and the mean (SD) body mass index (BMI) was 23.7 (3) kg/m2. In the comparator study, 58% (164/282) were women; the mean (SD) age was 27 (6.4) years, mean weight was 71 kg, and mean (SD) BMI was 24.2 (3) kg/m2. In the dose-finding study, the AZD3582 750-, 1500-, and 2250-mg groups were superior to placebo in the primary variables "time to rescue medication (0-8 hours)" (hazard ratios [HRs] [95% CIs], 0.17 [0.07-0.42], P < 0.003; 0.23 [0.11-0.50], P < 0.001; and 0.15 [0.06-0.36], P < 0.001, respectively), "time to meaningful pain relief" (HRs [95% CIs], 3.42 [1.87-6.25], P < 0.003; 2.49 [1.37-4.50], P < 0.003; and 3.07 [1.70-5.55], P < 0.001, respectively), and MPID (analysis of covariance [ANCOVA] least squares mean [LSM] differences [95% CIs], 25.8 [17.3-34.4], P < 0.003; 20.4 [12.1-28.7], P < 0.003; and 29.3 [20.9-37.6], P < 0.001, respectively). AZD3582 and naproxen did not show any statistically significant differences for the 3 primary variables, except that naproxen was superior to the AZD3582 375-mg dose for the variables time to meaningful pain relief (HR difference, 0.48 [95% CI, 0.29-0.78], P < 0.004) and MPID (difference in ANCOVA LSM, -10.2, [95% CI, -18.2 to -2.2], P < 0.012). The median times to meaningful pain relief were 115 minutes for AZD3582 375 mg, 66 minutes for 750 mg, 85 minutes for 1500 mg, 81 minutes for 2250 mg, and 162 minutes for placebo (P = NS, P = 0.003, P < 0.003, and P < 0.001, respectively). The median time to first rescue medication was 144 minutes for placebo, and <50% of the subjects on any of the AZD3582 doses or naproxen took rescue medication within 8 hours after dosing. In the comparator study, AZD3582 750 mg was superior to placebo in "time to rescue medication (0-24 hours)" (HR [95% CI], 0.4 [0.3-0.6], P < 0.001), "time to confirmed perceptible pain relief" (2.1 [1.1-3.8], P = 0.02), and MPID (11.9 [4.2-19.5], P = 0.002). However, inferiority of AZD3582 to rofecoxib for MPID could not be excluded (tolerance limit of 10 mm; P = NS for noninferiority testing). The median times to confirmed perceptible pain relief were 45 minutes for AZD3582 500 mg, 40 minutes for 750 mg, and 37 minutes for rofecoxib. The median times to first rescue medication were 218 minutes for AZD3582 500 mg, 365 minutes for 750 mg, 635 minutes for rofecoxib, and 90 minutes for placebo. Overall, AZD3582 was well tolerated. However, an effect on orthostatic blood pressure could not be excluded because there seemed to be more subjects with dizziness and orthostatic blood pressure reduction who were administered AZD3582 > or =750 mg. The proportions of patients with vertigo and decreased orthostatic blood pressure each group were as follows: AZD3582 500 mg, 6%; AZD3582 750 mg, 12%; rofecoxib, 3%; and placebo, 5%.

CONCLUSIONS

AZD3582 750 mg had similar analgesic efficacy as equimolar doses of naproxen, but noninferiority to rofecoxib was not demonstrated.

Combining paracetamol with a selective cyclooxygenase-2 inhibitor for acute pain relief after third molar surgery: a randomized, double-blind, placebo-controlled study

Severe pain after third molar surgery is often encountered and more effective treatment regimes are warranted. The objective of this study was to evaluate if the combination of paracetamol and rofecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, improves analgesic effects following third molar surgery compared with rofecoxib alone. Paracetamol alone was also evaluated. Altogether 120 patients with moderate to severe pain after third molar surgery were given a single postoperative dose of one of the following treatments: rofecoxib + paracetamol; rofecoxib alone; paracetamol alone; or placebo. Patients assessed level of pain and pain relief every 30 min for 8 h after surgery, and made a global evaluation of the medication 4 and 8 h after surgery. Paracetamol and rofecoxib combined improved the analgesic effect compared with rofecoxib alone for the first 1.5 h. Rofecoxib alone and the combination of paracetamol and rofecoxib had a significantly better analgesic effect than paracetamol alone from 3 h onwards. The early onset of pain relief for the combination of paracetamol and rofecoxib, compared with rofecoxib alone, could be of great importance when treating acute pain after third molar surgery. After data collection for this study, rofecoxib was withdrawn from the market as a result of reported fatal cardiovascular events. Whether this is relevant for short-term use is unknown, but it has to be considered before rofecoxib may be used for pain relief following third molar surgery.

The use of COX-2 inhibitors for acute dental pain: A second look

BACKGROUND

On the basis of their perceived better safety profile compared with other analgesic agents, cyclo-oxygenase-2 (COX-2) inhibitors have been prescribed frequently as first-line agents to treat acute dental pain. However, recently identified cardiovascular adverse reactions associated with these drugs mandate a reappraisal of their use in dental practice. TYPES OF STUDIES REVIEWED. The authors reviewed 18 clinical studies that evaluated the efficacy of a COX-2 inhibitor for the treatment of acute dental pain. All of the studies used the widely established third-molar surgical extraction model to induce postsurgical inflammatory based pain, and all were randomized, double-blinded and placebo-controlled. However, numerous vagaries in overall study design made direct comparisons difficult.

RESULTS

None of the studies established any of the COX-2 inhibitors as clearly better than ibuprofen, the current gold standard for the treatment of surgically induced dental pain. However, in single-dosing scenarios, the COX-2 inhibitor often demonstrated a longer duration of action compared with ibuprofen.

CLINCAL IMPLICATIONS

The evidence to date fails to demonstrate any therapeutic advantage to using a COX-2 inhibitor to treat acute dental pain compared with ibuprofen. In the rare event that a COX-2 inhibitor may be appropriate, the clinician must inform the patient of the potential risks, and the drug should be used for the shortest possible time.

Analgesic effects of intrathecally administered celecoxib, a cyclooxygenase-2 inhibitor, in the tail flick test and the formalin test in rats

BACKGROUND

The analgesic effects of celecoxib, a cyclooxygenase-2 (COX-2) inhibitor, on formalin-induced pain are still controversial. The purpose of this study was to examine the analgesic effects of intrathecally administered celecoxib on inflammatory induced pain, thermal-induced pain and hemodynamics.

METHODS

Male Sprague-Dawley rats with lumbar intrathecal catheters were tested via their tail withdrawal response to thermal stimulation (tail flick test) and via their paw flinching and shaking response to subcutaneous formalin injection into the hind paw (formalin test) after intrathecal administration of celecoxib. The blood pressure, pulse rate and behavioral side-effects were also examined.

RESULTS

Even the maximum available dose of celecoxib (200 microg/20 microl) had little effect in the tail flick test. In the formalin test, celecoxib induced a dose-dependent decrease in the flinch response in both phases 1 and 2. The 50% effective doses were 0.025 microg (95% confidence interval, 0.007-0.082 microg) in phase 1, 0.026 microg (0.010-0.045 microg) in phase 2a and 0.001 microg (0.00009-0.010 microg) in phase 2b. With the doses used in this study, the blood pressure and pulse rate did not change and no motor disturbance or behavioral side-effects were observed.

CONCLUSION

Intrathecal administration of celecoxib decreased inflammatory acute and facilitated pain without any hemodynamic or behavioral side-effects, but had no effect on acute thermal pain.