Levels of enzymatic antioxidants activities in mononuclear cells and skin reactivity to sodium dodecyl sulphate

Practice Advisory on the Appropriate Use of NSAIDs in Primary Care

Cyclo-oxygenase (COX)-2 selective and nonselective nonsteroidal anti-inflammatory drugs (NSAIDs) are important in managing acute and chronic pain secondary to inflammation. As a greater understanding of the risks of gastrointestinal (GI), cardiovascular (CV) and renal events with NSAIDs use has emerged, guidelines have evolved to reflect differences in risks among NSAIDs. Updated guidelines have yet to reflect new evidence from recent trials which showed similar CV event rates with celecoxib compared to naproxen and ibuprofen, and significantly better GI tolerability for celecoxib. This practice advisory paper aims to present consensus statements and associated guidance regarding appropriate NSAID use based on a review of current evidence by a multidisciplinary group of expert clinicians. This paper is especially intended to guide primary care practitioners within Asia in the appropriate use of NSAIDs in primary care. Following a literature review, group members used a modified Delphi consensus process to determine agreement with selected recommendations. Agreement with a statement by 75% of total voting members was defined a priori as consensus. For low GI risk patients, any nonselective NSAID plus proton pump inhibitor (PPI) or celecoxib alone is acceptable treatment when CV risk is low; for high CV risk patients, low-dose celecoxib or naproxen plus PPI is appropriate. For high GI risk patients, celecoxib plus PPI is acceptable for low CV risk patients; low-dose celecoxib plus PPI is appropriate for high CV risk patients, with the alternative to avoid NSAIDs and consider opioids instead. Appropriate NSAID prescription assumes that the patient has normal renal function at commencement, with ongoing monitoring recommended. In conclusion, appropriate NSAID use requires consideration of all risks.

Modification of the lead molecule: Tryptophan and piperidine appended triazines reversing inflammation and hyeperalgesia in rats

The structural optimization of the molecules making them to fit into the active site pocket of COX-2 occupying the same space as covered by the natural substrate arachidonic acid helped in the emergence of compound 10 as an efficacious anti-inflammatory agent. Selective for COX-2 over COX-1, compound 10 exhibited IC₅₀ 0.02 µM for COX-2 and reversed acetic acid induced inflammation in rats by 73% when used at 10 mg kg^-1 dose and the same dose of the compound also rescued the animals from inflammatory phase of formalin induced hyperalgesia. As evidenced by the results of molecular modeling studies supported by the nuclear Overhauser enhancement data, the appropriate geometry of the molecule in the active site pocket of COX-2 contributing to its H-bond/hydrophobic interactions with Ser530, Trp387 and Tyr385 seems responsible for the enzyme inhibitory activity of the compound.

Design and Synthesis of Aza-/Oxa Heterocycle-Based Conjugates as Novel Anti-Inflammatory Agents Targeting Cyclooxygenase-2

A library of hybrid molecules was procured by the combination of triazine-indole adduct with morpholine/piperidine/pyrrolidine and pyrazole/pyrimidine/oxindole moieties. Enzyme immunoassays on cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) identified compound 6 having an IC₅₀ value of 20 nM for COX-2 and 3000 nM for COX-1. The significant reduction in the formation of prostaglandin E₂ in the lipopolysaccharide-treated (COX-2-activated) human whole blood, almost no change in the production of thromboxane B₂ in the calcium ionophore-treated (COX-1-activated) sample of human whole blood, and the mechanistic studies on Swiss albino mice ensured that compound 6 is selective for COX-2. The association constant (K_a) of compound 6 with COX-2 was found to be of the order of 0.48 × 10⁶ M^-1. The diffusion spectroscopy experiments and relaxation time (T₁) calculations of compound 6 in the presence of COX-2 assisted in identifying the site-specific interactions of 6 with the enzyme, and these results fall into nice correlation with the theoretical data obtained from molecular docking and quantitative structure-activity relationship studies. With maximum tolerable dose >2000 mg kg^-1, compound 6 made 68 and 32% reduction in formalin-induced analgesia and carrageenan-induced inflammation in Swiss albino mice.

Bromoethylindole (BEI-9) redirects NF-κB signaling induced by camptothecin and TNFα to promote cell death in colon cancer cells

Chemotherapeutic regimens containing camptothecin (CPT), 5-fluorouracil, and oxaliplatin are used to treat advanced colorectal cancer. We previously reported that an indole derivative, 3-(2-bromoethyl)indole (BEI-9), inhibited the proliferation of colon cancer cells and suppressed NF-κB activation. Here, we show that a combination of BEI-9 with either CPT or tumor necrosis factor alpha (TNFα) enhances cell death. Using colorectal cancer cells, we examined the activation of NF-κB by drugs, the potential of BEI-9 for inhibiting drug-induced NF-κB activation, and the enhancement of cell death by combination treatments. Cells were treated with the chemotherapeutic drugs alone or in combination with BEI-9. NF-κB activation, cell cycle profiles, DNA-damage response, markers of cell death signaling and targets of NF-κB were evaluated to determine the effects of single and co-treatments. The combination of BEI-9 with CPT or TNFα inhibited NF-κB activation and reduced the expression of NF-κB-responsive genes, Bcl-xL and COX2. Compared to CPT or BEI-9 alone, sequential treatment of the cells with CPT and BEI-9 significantly enhanced caspase activation and cell death. Co-treatment with TNFα and BEI-9 also caused more cytotoxicity than TNFα or BEI-9 alone. Combined BEI-9 and TNFα enhanced cell death through caspase activation and cleavage of the switch-protein, RIP1 kinase. BEI-9 reduced the expression of COX2 both alone and in combination with CPT or TNF. We postulate that BEI-9 enhances the effects of these drugs on cancer cells by turning off or redirecting NF-κB signaling. Therefore, the combination of BEI-9 with drugs that activate NF-κB needs to be evaluated for clinical applications.

Modulating Neuroinflammation to Treat Neuropsychiatric Disorders

Neuroinflammation is recognised as one of the potential mechanisms mediating the onset of a broad range of psychiatric disorders and may contribute to nonresponsiveness to current therapies. Both preclinical and clinical studies have indicated that aberrant inflammatory responses can result in altered behavioral responses and cognitive deficits. In this review, we discuss the role of inflammation in the pathogenesis of neuropsychiatric disorders and ask the question if certain genetic copy-number variants (CNVs) associated with psychiatric disorders might play a role in modulating inflammation. Furthermore, we detail some of the potential treatment strategies for psychiatric disorders that may operate by altering inflammatory responses.

Response of ADA and Its Isoenzymes in Mice Infected by Trichinella Spiralis and Treated with Mimosine

Infections caused by the nematode Trichinella spiralis (T. spiralis) are chatacterized by an inflammatory response in the host. The aim of this study was to identify and evaluate markers for monitoring mice infected with T. spiralis and treated with or without mimosine. The markers that have been used were total and differential white blood cell counts, subpopulations of lymphocytes, serum tADA and its isoenzymes ADA1 and ADA2 activity. The study included 3 groups of BALB/c mice. Group A consisted of 16 healthy mice, Group B of 16 mice infected with T. spiralis and treated with saline, and Group C of 16 mice infected with T. spiralis and treated with mimosine. The measurements were made once per week for the first six weeks continuously following the infection. According to our results, leukocytosis, lymphocytosis and increased percentages of adhesion molecules and CD4 lymphocytes were present in groups B and C one week post-infection. Total ADA activity as well as ADA1 and ADA2 was higher in groups B and C versus group A from the first week post-infection. The levels of tADA activity, ADA1 and ADA2 were higher in group B compared to those of group C and the difference was statisticaly sigificant (p<0.05) during the 4th week post-infection. The majority of tADA activity, essential for an efficient immune response, was derived from ADA1 which may have been produced by infected tissues. The elevated activities of tADA and ADA1 may be sensitive markers for infection of T. spiralis and for monitoring the course of the infection.

Does Oxidative Stress Play a Role in the Pathogenesis of Urticarias?

Radical oxygen species (ROS) modulate various cellular processes and are involved in physiologic and pathologic conditions, including inflammation. There is growing evidence that supports the existence of an abnormal redox status in some chronic inflammatory skin diseases, including contact dermatitis, atopic dermatitis and psoriasis. This review introduces some general aspects on the role of oxidative stress in cutaneous inflammation, with special emphasis on urticarias, summarizing recent novel findings derived from the study of physical urticarias and chronic idiopathic urticaria.

Inhibition of MCP-1 and MIP-2 Chemokines in Murine Trichinellosis: Effect of the Anti-Inflammatory Compound L-Mimosine

Mimosine, is a plant amino-acid which has been reported to block DNA replication in mammalian cells and to arrest cells reversibly towards the end of the G1 phase or at the beginning of the S phase. In this study, 42 mice were infected with T. spiralis, a nematode parasite, and treated with the anti-inflammatory compound L-mimosine, to determine if any alteration in the chronic inflammatory state occurred, by investigating the host's immunological response. MCP-1, a C-C chemokine and MIP-2, a C-X-C chemokine were tested and measured in the sera of infected animals, after 1, 10, 20, 30, 40, 50 and 60 days postinfection, by ELISA method. The diaphragm/muscle and the masseters of the infected mice, were tested for inflammatory response. We found that MCP-1 was partially inhibited by L-mimosine, while MIP-2 was totally inhibited. Moreover, in sections of the diaphragm and masseters, the infiltration of inflammatory cells such as macrophages, lymphocytes and eosinophils were more intense in untreated animals compared to those treated with L-mimosine. These findings show, that L-mimosine may have an inhibitory effect on MCP-1 and MIP-2 serum levels in Trichinellosis and may influence the recruitment of inflammatory cells and the intensity of the inflammatory reaction in this parasitic disease.

A Scavenger Role for Nitric Oxide in the Aged Rat Kidney

Progressive ageing is associated with an increment of biomolecules modified through oxidation as a result of the action of free radicals deriving from reactive oxygen species that attack biomolecules. During ageing many alterations of renal functions have been reported. Renal ageing is associated with a progressive decline of glomerular filtration, renal blood flow and augmented vascular resistance. The kidney is a very important source of inducible nitric oxide synthase (iNOS) in both epithelial and vascular structures. In this study we have investigated mRNA and protein iNOS expression and localization and nitric oxide (NO) production in young and aged rats. An increased expression of iNOS occurs in rat kidney during ageing. In the aged rat, an increase in the values of both iNOS-RNA and iNOS protein was observed through rtPCR and Western blot analysis. The activities of three isoforms of NOS were also seen. In the aged rat kidney the production of NO decreased, due to the reduction of the activities of the three NOS. This suggests that in the aged rat a progressive increase of superoxide anion does not imply an increase in the production of NO which functions as a scavenger molecule, causing oxidative stress with accumulation of reactive oxygen species (ROS).

Infliximab Monotherapy for Refractory Psoriasis: Preliminary Results

Tumour necrosis factor (TNF)-alpha plays an important role in the pathogenesis of psoriasis. Infliximab is an anti-TNF-alpha chimeric monoclonal antibody, which is licensed for the treatment of rheumatoid arthritis and Crohn's disease. Some reports have shown the efficacy of infliximab, either in monotherapy or in combination with methotrexate, for the treatment of psoriatic arthropathy and psoriasis.

The efficacy and tolerability of infliximab monotherapy was evaluated in 29 patients with moderate to severe psoriasis, unresponsive to conventional treatments. Fourteen patients suffered from concomitant arthropathy. Patients received intravenous infliximab, 5mg/kg, at weeks 0, 2, and 6. After this 3-dose-induction regimen, patients were followed-up at monthly intervals and retreated with a single-dose infusion in case of relapse of signs and symptoms. Clinical assessment was performed using the psoriasis area and severity index (PASI) to monitor psoriasis activity; pruritus and joint pain were assessed on a scale of 0 to 3. A marked improvement of skin lesions and subjective symptoms was noted in the majority of patients; an excellent reduction of PASI score (⩾75%) was observed in 13.8% of cases at week 2, 71.4% at week 6 and 78.6% at week 10. During the follow-up period, some patients maintained satisfactory clinical results without requiring any additional infusions. In general, skin lesions showed a trend towards a more prolonged and sustained improvement as compared with subjective symptoms. Treatment was well tolerated and no serious adverse events occurred.

Cyclooxygenase-2 independent effects of cyclooxygenase-2 inhibitors on oxidative stress and intracellular glutathione content in normal and malignant human B-cells

We recently reported that inhibition of Cyclooxygenase-2 (Cox-2) reduced human B-CLL proliferation and survival. Herein, we investigated the mechanisms whereby small molecule Cox-2 selective inhibitors, SC-58125 (a Celebrex analog) and CAY10404 blunt survival of human B-cell lymphomas and chronic lymphocytic leukemia B-cells. SC-58125 and OSU03012 (a Celebrex analog that lacks Cox-2 inhibitory activity) both decreased intracellular glutathione (GSH) content in malignant human B-cells, as well as in Cox-2 deficient mouse B-cells. This new finding supports Cox-2 independent effects of SC-58125. Interestingly, SC-58125 also significantly increased B-cell reactive oxygen species (ROS) production, suggesting that ROS are a pathway that reduces malignant cell survival. Addition of GSH ethyl ester protected B lymphomas from the increased mitochondrial membrane permeability and reduced survival induced by SC-58125. Moreover, the SC-58125-mediated GSH depletion resulted in elevated steady-state levels of the glutamate cysteine ligase catalytic subunit mRNA and protein. These new findings of increased ROS and diminished GSH levels following SC-58125 exposure support novel mechanisms whereby a Cox-2 selective inhibitor reduces malignant B-cell survival. These observations also support the concept that certain Cox-2 selective inhibitors may have therapeutic value in combination with other drugs to kill malignant B lineage cells.

Biochemical aspects of inflammation

This review considers biochemical aspects of inflammation. The international literature until December 2006 has been analyzed, with the principal attention paid to the most dynamic problems: enzymology of inflammation, its regulation by hormones and signal transducers, and negative feedbacks, which underlie intensive current studies on pathogenesis, diagnostics, and therapy of inflammation. Such achievements as discoveries of defensins, toll-like receptors, interconnections of inflammation and iron metabolism, the roles of oxidative stress and antioxidant defense, lipoxins, inflammatory components of "non-inflammatory" diseases, and action mechanisms of effective drugs are discussed.

Cyclooxygenase isozymes in oral squamous cell carcinoma:a real-time RT-PCR study with clinic pathological correlations

COX-2 expression in tumour cells has been associated with carcinogenesis in many human neoplasms, including head and neck cancer, while the COX-1 isoform of the cyclooxygenase enzyme is constitutively expressed in normal tissues. We measured COX-1 and COX-2 m-RNA expression in samples of both oral cancer and matched oral mucosa from 22 patients by RealTime RT-PCR; clinic pathological data (grading, TNM staging, inflammation, follow-up) of all patients were available for statistical evaluation. Most of the tumor samples in our study expressed at least one cyclooxygenase enzyme (COX-1 or COX-2 mRNA) more than their matched normal oral mucosa (p<0.05), with no correlation with the entity of inflammation, and a significant inverse relationship was found between COX-1 and COX-2 in each sample. Higher levels of COX-2 expression were associated with poor disease-free survival (p<0.05), but not with overall survival and higher tumor stage and grade. Our results suggest that COX-1 may play a role in oral carcinogenesis, and could be regarded as a potential therapeutic target by chemo preventive drugs; moreover, COX-2 expression might be addressed as a new prognostic tool in the clinical management of OSCC.

Lumiracoxib in the management of osteoarthritis and acute pain

Lumiracoxib is a highly selective COX-2 inhibitor with a novel chemical structure and a relatively short plasma half-life. It has been approved in > 40 countries for the symptomatic treatment of osteoarthritis and/or acute pain related to primary dysmenorrhoea and dental or orthopaedic surgery. In these conditions, lumiracoxib has proved to be as effective as standard doses of conventional NSAIDs and other COX-2 selective inhibitors (coxibs). According to the Therapeutic Arthritis Research Gastrointestinal Trial, which enrolled 18,325 patients with osteoarthritis, lumiracoxib 400 mg/day (four times its recommended dosage) was associated with a significant decrease in the risk of ulcer complications compared with naproxen 1000 mg/day and ibuprofen 2400 mg/day, at least in the population not taking low-dose aspirin. The atherothrombotic potential of NSAIDs, especially coxibs, has been much debated. In this respect, available data do not suggest that lumiracoxib may be associated with an increased hazard of cardiovascular events compared with non-selective NSAIDs. Finally, lumiracoxib may be an effective and safe drug provided both physicians and patients will comply with its approved indications and contraindications.

Channelling of COX-2 inhibitors to patients at higher gastrointestinal risk but not at lower cardiovascular risk: the Cox2 inhibitors and tNSAIDs description of users (CADEUS) study

PURPOSE

To describe the characteristics of users of cyclo-oxygenase (COX)-2 inhibitors and traditional nonselective non-steroidal anti-inflammatory drugs (tNSAIDs) in France.

METHODS

Between 1 August 2003 and 31 July 2004, patients who received at least one dispensing of celecoxib, rofecoxib or tNSAIDs were randomly sampled with a 1:1:2 target ratio within the French National Healthcare Insurance database. Patients and prescribers were asked to fill a questionnaire on socio-demographic characteristics, NSAID indication and use and previous medical history. For each respondent, healthcare resources used in the 6 months before inclusion were extracted from the database. Multivariate logistic regression was used to study the determinants of a first COX-2 inhibitor dispensing.

RESULTS

Of the 45 217 patients included, 13 065 COX-2 inhibitors and 13 553 tNSAID users had prescriber data. Ninety seven per cent of COX-2 inhibitor prescriptions were for 'rheumatological' indications, whereas 37% of tNSAIDs use was for benign diseases (n = 2643) or analgesia (n = 2318). Among patients with rheumatological indications (n = 4730) and a first COX-2 inhibitor (n = 2427) or tNSAID (n = 2303) dispensing, multivariate analysis of factors associated with COX-2 inhibitors dispensing showed that, compared to new tNSAID users, new COX-2 inhibitor users were older, more often female, on sick leave or unemployed. COX-2 use was also associated with previous gastrointestinal history and previous gastroprotective agent dispensing, but not with previous cardiovascular (CV) history.

CONCLUSION

The choice of NSAID depended largely on indication and on previous gastrointestinal history, in line with the recommendations of the French health authorities. Possible knowledge of CV risk associated with COX-2 inhibitors did not influence prescribing.

Cyclooxygenase-2 Inhibition Attenuates Antibody Responses against Human Papillomavirus-Like Particles

Vaccination to generate protective humoral immunity against infectious disease is becoming increasingly important due to emerging strains of virus, poorly immunogenic vaccines, and the threat of bioterrorism. We demonstrate that cyclooxygenase-2 (Cox-2) is crucial for optimal Ab responses to a model vaccine, human papillomavirus type 16 virus-like particles (HPV 16 VLPs). Cox-2-deficient mice produce 70% less IgG, 50% fewer Ab-secreting cells, and 10-fold less neutralizing Ab to HPV 16 VLP vaccination compared with wild-type mice. The reduction in Ab production by Cox-2(-/-) mice was partially due to a decrease in class switching. SC-58125, a structural analog of the Cox-2-selective inhibitor Celebrex reduced by approximately 70% human memory B cell differentiation to HPV 16 VLP IgG-secreting cells. The widespread use of nonsteroidal anti-inflammatory drugs and Cox-2-selective inhibitory drugs may therefore reduce vaccine efficacy, especially when vaccines are poorly immunogenic or the target population is poorly responsive to immunization.

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.

APRIL and BAFF promote increased viability of replicating human B2 cells via mechanism involving cyclooxygenase 2

Of relevance to both protective and pathogenic responses to Ag is the recent finding that soluble molecules of the innate immune system, i.e., IL-4, B cell-activation factor of the TNF family (BAFF), and C3, exhibit significant synergy in promoting the clonal expansion of human B2 cells following low-level BCR ligation. Although IL-4, BAFF, and C3dg each contribute to early cell cycle entry and progression to S phase, only BAFF promotes later sustained viability of progeny needed for continued cycling. The present study sought to further clarify the mechanisms for BAFF's multiple functions. By comparing BAFF and a proliferation-inducing ligand (APRIL) efficacy at different stages in the response (only BAFF binds BR3; both bind transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI) and B cell maturation Ag, the early role was attributed to BR3, while the later role was attributed to TACI/B cell maturation Ag. Importantly, BAFF- and APRIL-promoted viability of cycling lymphoblasts was associated with sustained expression of cyclooxygenase 2 (COX-2), the rate-limiting enzyme for PGE2 synthesis, within replicating cells. Supernatants of cultures with BAFF and APRIL contained elevated PGE2. Although COX-2 inhibitors diminished daughter cell viability, exogenous PGE2 (1-1000 nM) increased the viability and recovery of lymphoblasts. Increased yield of viable progeny was associated with elevated Mcl-1, suggesting that a BAFF/APRIL --> TACI --> COX-2 --> PGE2--> Mcl-1 pathway reduces activation-related, mitochondrial apoptosis in replicating human B2 cell clones.

Polyamine-mediated reduction in human airway epithelial migration in response to wounding is PGE2 dependent through decreases in COX-2 and cPLA2 protein levels

Both ornithine decarboxylase inhibition to deplete polyamines and cyclooxygenase inhibition diminish the migration response to injury of human airway epithelial cells in tissue culture monolayers by approximately 75%. Restoration of normal migration responses is achieved in the polyamine depleted system either by exogenous reconstitution of polyamines or the addition of prostaglandin E(2) (PGE(2)). However, only PGE(2) was able to restore migration in the cyclooxygenase-inhibited systems. Western blot for cyclooxygenase-2 and cytosolic phospholipase A(2) protein levels and ELISAs for PGE(2) secretion demonstrate dramatic increases over 24-48 h after monolayer wounding. These increases are completely abolished by polyamine depletion or cyclooxygenase inhibition. We conclude that polyamine inhibition decreases cellular migration in response to injury in airway epithelial cells at least in part through inhibiting normal PGE(2) production in response to injury. This may be brought about by decreases in cytosolic phospholipase A(2) and cyclooxygenase-2 protein levels.

Activated human B lymphocytes express cyclooxygenase-2 and cyclooxygenase inhibitors attenuate antibody production

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used for the treatment of inflammatory diseases and target cyclooxygenases 1 and 2 (Cox-1, Cox-2) that are responsible for PG production. Newer Cox-2-selective drugs have been heavily prescribed to quench inflammation. Little is known about whether or not these drugs influence human B lymphocytes and their ability to produce Ab. We report herein that activated human B cells not only highly express Cox-2 and produce PGs, but that the NSAID indomethacin and Cox-2-selective drugs profoundly inhibit the ability of human B cells to produce IgG and IgM in vitro. Human blood B cells highly express Cox-2 mRNA and protein and produce PGs after activation with CD40L, pansorbin, or CD40L plus BCR engagement. Cox-2 is also highly expressed by human tonsil B cells, as shown by immunohistochemistry. Cox-inhibiting drugs modestly affect purified B cell proliferation but profoundly reduce Ab production. The ability of whole blood to produce IgM and IgG following stimulation is also strongly inhibited. In support that Cox-2 plays a seminal role in B lymphocyte Ab production, Cox-2 knockout mice have 64% less IgM and 35% less IgG than normal littermate controls. These findings support that NSAIDs and the new Cox-2-selective drugs have an unsuspected target, the B cell, and attenuate Ab production in humans. Use of NSAIDs may therefore influence autoantibody production in autoimmune diseases and may dampen humoral immunity in response to antigenic challenge/vaccination.

The effects of selective and nonselective cyclooxygenase inhibitors on endothelin-1-induced fever in rats

It was previously shown that sustained fever can be induced in rats by central injection of endothelin-1 (ET-1). This peptide appears to participate in the mechanism(s) of LPS-induced fever, which is reduced by pretreatments with ETB receptor antagonists. In this study, we compared the effects of a nonselective cyclooxygenase (COX) inhibitor, indomethacin, with those of two selective COX-2 inhibitors, celecoxib and lumiracoxib, on ET-1-induced fever in rats. Fever induced in conscious animals by ET-1 (1 pmol icv) or LPS (5 μg/kg iv) was prevented by pretreatments with celecoxib (5 and 10 mg/kg) or lumiracoxib (5 mg/kg) given by oral gavage 1 h before stimuli. Lower doses of celecoxib had partial (2.5 mg/kg) or no effect (1 mg/kg). Indomethacin (2 mg/kg ip) partially inhibited fever induced by LPS but had no effect on ET-1-induced fever. The levels of PGE2 and PGF2α in the cerebrospinal fluid (CSF) of pentobarbital sodium-anesthetized rats were significantly increased 3 h after the injection of LPS or ET-1. The latter increase was abolished by celecoxib at all tested doses and by indomethacin. In conclusion, selective COX-2 inhibitors were able to prevent ET-1-induced fever, indicating a role for COX-2 in this phenomenon. However, the fact that reduced CSF PG levels obtained with indomethacin and a low dose of celecoxib are not accompanied by changes in fever induced by ET-1, along with the lack of inhibitory effects of indomethacin on ET-1 fever, suggests that the latter might also involve COX-2-independent mechanisms.

Influence of cigarette smoking on vitamin E, vitamin A, beta-carotene and lycopene concentrations in human pre-ovulatory follicular fluid

Increasing evidence suggests that fat soluble vitamins and micronutrients have the potential for local modulation of follicular development. Cigarette smoking has been associated with accelerated follicular depletion and derangement of reproductive functions. The present study was initiated to investigate the impact of cigarette smoking on follicular and plasma concentrations of vitamin A, vitamin E, lycopene and beta-carotene. Samples were collected from 17 smokers and 43 non-smoking women undergoing assisted reproduction techniques. Assays were carried out by a reverse-phase high-pressure liquid chromatography (HPLC) method. Smokers had significantly (P < 0.05) lower levels of follicular fluid beta-carotene in comparison to non-smokers (0.02 +/- 0.02 vs. 0.09 +/- 0.02, respectively). No other significant influences on follicular and plasma concentrations were noted. Smokers showed a significantly (P < 0.05) lower fertilization rate in comparison to non-smokers, (55.9 % vs. 71.5 % , respectively). It is postulated that follicular depletion of the antioxidant beta-carotene occurs in response to oxidative stress imposed by cigarette smoke.

A liquid chromatography-mass spectrometry method for the quanti?cation of both etoricoxib and valdecoxib in human plasma

A practicable and selective liquid chromatography-mass spectrometry assay for the determination of two cyclooxygenase-2 inhibitors, etoricoxib and valdecoxib, in human plasma is presented. The analytical technique is based on reversed-phase high-performance liquid chromatography (HPLC) coupled to atmospheric pressure chemical ionisation (APCI) mass spectrometry (Finnigan Mat LCQ ion trap). Mass analysis was performed in the positive ion mode. The ion trap was operated in the tandem MS mode (MS2) and the transitions of etoricoxib (m/z 359.2 --> 280.3) and valdecoxib (m/z 315.1 --> 235.1) were followed by selected reaction monitoring. Retention times of etoricoxib and valdecoxib were 1.05 and 1.08 min, respectively. The method was validated over a linear range 10-2500 and 5-1000 microg/L using the other substrate as internal standard. After validation, the method was used to study the pharmacokinetic pro fi le of etoricoxib or valdecoxib in a healthy volunteer after administration of a single oral dose (valdecoxib, 20 mg; etoricoxib, 90 mg). The presented method was suf fi cient to cover more than 90% of the area under the plasma concentration time curve.

ABT-963 [2-(3,4-Difluoro-phenyl)-4-(3-hydroxy-3-methyl-butoxy)-5-(4-methanesulfonyl-phenyl)-2H-pyridazin-3-one], A Highly Potent and Selective Disubstituted Pyridazinone Cyclooxgenase-2 Inhibitor

Nonsteriodal anti-inflammatory drugs (NSAIDs) are efficacious for the treatment of pain associated with inflammatory disease. Clinical experience with marketed selective cyclooxygenase-2 (COX-2) inhibitors (celecoxib, rofecoxib, and valdecoxib) has confirmed the utility of these agents in the treatment of inflammatory pain with an improved gastrointestinal safety profile relative to NSAID comparators. These COX-2 inhibitors belong to the same structural class. Each contains a core heterocyclic ring with two appropriately substituted phenyl rings appended to adjacent atoms. Here, we report the identification of vicinally disubstituted pyridazinones as potent and selective COX-2 inhibitors. The lead compound in the series, ABT-963 [2-(3,4-difluoro-phenyl)-4-(3-hydroxy-3-methyl-butoxy)-5-(4-methanesulfonyl-phenyl)-2H-pyridazin-3-one], has excellent selectivity (ratio of 276, COX-2/COX-1) in human whole blood, improved aqueous solubility compared with celecoxib and rofecoxib, high oral anti-inflammatory potency in vivo, and gastric safety in the animal studies. After oral administration, ABT-963 reduced prostaglandin E2 production in the rat carrageenan air pouch model (ED50 of 0.4 mg/kg) and reduced the edema in the carrageenan induced paw edema model with an ED30 of 1.9 mg/kg. ABT-963 dose dependently reduced nociception in the carrageenan hyperalgesia model (ED50 of 3.1 mg/kg). After 14 days of dosing in the adjuvant arthritis model, ABT-963 had an ED(50) of 1.0 mg/kg in reducing the swelling of the hind paws. Magnetic resonance imaging examination of the diseased paws in the adjuvant model showed that ABT-963 significantly reduced bone loss and soft tissue destruction. ABT-963 is a highly selective COX-2 inhibitor that may have utility in the treatment of the pain and inflammation associated with arthritis.