Inhibitor Celecoxib (inhibitor + celecoxib)

Distribution by Scientific Domains


Selected Abstracts


Celecoxib as an adjunct in the treatment of depressive or mixed episodes of bipolar disorder: a double-blind, randomized, placebo-controlled study,,

HUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 2 2008
Fabiano G. Nery
Abstract Objective To investigate whether the cox-2 inhibitor celecoxib has antidepressant effects in bipolar disorder (BD) patients during depressive or mixed phases. Methods We studied 28 DSM-IV BD patients who were experiencing a depressive or mixed episode and were on a stable dose of a mood stabilizer or atypical antipsychotic medication. Subjects were randomized to receive 6 weeks of double-blind placebo or celecoxib (400,mg/day) treatment. Current mood stabilizer or antipsychotic medication remained at the same doses during the trial. Results Intention-to-treat analysis showed that the patients receiving celecoxib had lower Hamilton Depression Rating Scale (HamD) scores after 1 week of treatment compared to the patients receiving placebo, but this difference was not statistically significant (p,=,0.09). The improvement in the first week of treatment was statistically significant when the analysis included only the subjects who completed the full 6-week trial (p,=,0.03). The two groups did not differ significantly on depressive or manic symptoms from the second week until the end of the trial. Celecoxib was well tolerated with the exception of two subjects who dropped out of the study due to rash. Conclusions Our findings suggest that adjunctive treatment with celecoxib may produce a rapid-onset antidepressant effect in BD patients experiencing depressive or mixed episodes. Copyright © 2008 John Wiley & Sons, Ltd. [source]


Short-term dietary administration of celecoxib enhances the efficacy of tumor lysate-pulsed dendritic cell vaccines in treating murine breast cancer

INTERNATIONAL JOURNAL OF CANCER, Issue 9 2006
Tobias Hahn
Abstract Cyclooxygenase-2 (COX-2) is a rate-limiting enzyme in the synthesis of prostaglandins. It is over-expressed in multiple cancers and has been associated with diminished tumor immunity. Dendritic cells (DCs) are considered candidates for cancer immunotherapy due to their ability to process and present antigens to T cells and stimulate immune responses. However, DC-based vaccines have exhibited minimal effectiveness against established tumors. In this study, we evaluated the effect of short-term administration of the selective COX-2 inhibitor celecoxib on the efficacy of DC-based vaccines in preventing and treating established 4T1 murine mammary tumors. We show that dietary celecoxib alone significantly suppresses the growth of primary tumors and the incidence of lung metastases in the prophylactic setting but is less effective against pre-established tumors. However, we demonstrate that celecoxib administered after primary tumor establishment synergizes with tumor lysate-pulsed DC and the adjuvant, GM-CSF, to improve the antitumor immune response by suppressing primary tumor growth and markedly reducing the occurrence of lung metastases. This triple combination therapy elicits a tumor-specific immune response evidenced by elevated IFN-, and IL-4 secretion by CD4+ T cells and results in increased infiltration of CD4+ and CD8+ T cells to the tumor site. In addition, dietary celecoxib inhibits angiogenesis evidenced by decreased vascular proliferation within the tumor and serum vascular endothelial growth factor levels. These studies suggest that short-term celecoxib therapy in combination with DC vaccines may be safely used for treating metastatic breast cancer. © 2005 Wiley-Liss, Inc. [source]


Cyclooxygenase-2 inhibitor celecoxib augments chemotherapeutic drug-induced apoptosis by enhancing activation of caspase-3 and -9 in prostate cancer cells

INTERNATIONAL JOURNAL OF CANCER, Issue 3 2005
Devendra S. Dandekar
Abstract Many tumors constitutively express high levels of the inducible form of proinflammatory enzyme, cyclooxygenase-2 (COX-2). Increased COX-2 expression is associated with tumor cell resistance to many cytotoxic chemotherapy drugs. Furthermore, increased resistance to cytotoxic antitumor drugs is also known to be dependent on associated stromal cells in many tumors. We investigated whether prostate tumor-associated stromal cells, marrow-derived osteoblasts, affect cytotoxicity of 2 antitumor drugs, COL-3 and docetaxel (TXTR), and whether it is dependent on COX-2 activity. We further examined whether inhibiting the activity of COX-2 negate the stroma-induced decrease in drug sensitivity in tumor cells. COX-2-specific inhibitor celecoxib (CXB) was used to inhibit COX-2 activity and associated alteration in cell death signaling was investigated. Coculturing PC-3ML cells with osteoblasts decreased the cytotoxicity of the tested antitumor drugs and was associated with increased COX-2 activity in PC-3ML cells. A significant decrease in drug-induced PGE2 increase and an increase in cytotoxicity were observed when cells were treated with COL-3 or TXTR combined with CXB. Cytotoxicity of single or combination treatment increased apoptosis, which was associated with caspase-3 and -9 activation, PARP cleavage, increased BAD protein, but decreased protein levels of XIAP and BCL- xL. Oral administration of CXB (40 mg/kg) to mice with PC-3ML tumors for 42 days increased tumor latency, decreased tumor growth and enhanced tumor control with COL-3 or TXTR. Overall, a synergistic enhancement of antitumor activity in combination treatment was observed in vitro and an additive effect in vivo. These observations suggest a potential clinical use of combined dosing of COX-2 inhibitors and cytotoxic drugs at lower, nontoxic dose than currently used to treat advanced prostate cancer. © 2005 Wiley-Liss, Inc. [source]


PGE2 and IL-6 production by fibroblasts in response to titanium wear debris particles is mediated through a Cox-2 dependent pathway

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 1 2004
Susan V. Bukata
Aseptic loosening of orthopaedic implants is precipitated by wear debris-induced osteolysis. Central to this process are the pro-inflammatory mediators that are produced in response to wear by the fibroblastic cells, which comprise the majority of periprosthetic membranes. Since this pro-inflammatory cascade is mediated by a plethora of factors with redundant functions, it is imperative to establish a hierarchy. Two well-known fibroblast derived pro-inflammatory factors that stimulate wear debris-induced osteoclastic resorption are prostaglandin E2 (PGE2) and IL-6. However, their relationship to each other in this process is poorly defined. Here we show immunohistochemistry of retrieval membranes indicating that COX-2 is the principal cyclooxygenase responsible for PGE2 production in fibroblasts around failed implants. We also performed in vitro experiments with fibroblasts derived from wild-type (WT), COX-1 (,/,) and COX-2 (,/,) mice, which demonstrated that COX-2 is required for Ti wear debris-induced PGE2 production. Interestingly, COX-2 was also required for IL-6 production in these assays, which could be rescued by the addition of exogenous PGE2 (10,6 M). Pharmacology studies that utilized the COX-1 selective inhibitor SC 560, the COX-2 selective inhibitor celecoxib, and the nonselective COX inhibitor indomethacin confirmed these results. Taken together, these results indicate that selective inhibition of prostaglandin signaling could favorably impact aseptic loosening beyond its direct effects on PGE2 synthesis, in that it inhibits downstream pro-inflammatory/pro-osteoclastic cytokine production. © 2003 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source]


Inflammatory processes of prostate tissue microenvironment drive rat prostate carcinogenesis: Preventive effects of celecoxib

THE PROSTATE, Issue 2 2009
Narayanan K. Narayanan
Abstract BACKGROUND Prostate tissue microenvironment is susceptible to several risk factors including carcinogens, dietary factors, hormones, cytokines and growth factors that could induce chronic inflammation. Because of the difference in the serum levels and the intrinsic ability of monocytes/macrophages to cause harm, the transcriptional responses triggered by inflammatory stimuli must be controlled. Unfortunately, an in-depth association between prostate cancer and potential mediators of inflammation has not been completely investigated. METHODS To determine whether activated macrophage (infiltrating monocytes), iNOS and NF-,B are primary mediators of inflammation, besides COX-2, in prostate carcinogenesis, we examined tissue sections of rat prostate tumor induced by N -methyl- N -nitrosourea (MNU) plus testosterone in a follow-up study. We performed H&E and immunohsitochemical staining of the prostate tissue to detect specific markers of inflammation. RESULTS We report an increase in infiltrating monocyte, iNOS, NF-,Bp65, VEGF and TNF-, at the early and advanced stages of tumor growth in MNU plus testosterone treated rats. Monocyte infiltration was often found in the stromal and perivascular regions of the DL prostate. We conclude for the first time that prostate cancer induced by MNU plus testosterone partly involves mediators of inflammation which could trigger the process of carcinogenesis and cause loss of apoptosis. Selective COX-2 inhibitor celecoxib at a dose of 500 mg/kg/bw administered for 52 weeks reduced infiltrating monocytes, inhibited iNOS, NF-,B p65 expression, induced apoptosis and tumor growth inhibition. CONCLUSION Carcinogen plus testosterone induced prostate carcinogenesis showing activation of macrophage, iNOS and NF-,Bp65 could be prevented by celecoxib or related anti-inflammatory agents. Prostate 69: 133,141, 2009. © 2008 Wiley,Liss, Inc. [source]


Synthesis of New 2,3-Dihydroquinazolin-4(1H)-one Derivatives for Analgesic and Anti-inflammatory Evaluation

ARCHIV DER PHARMAZIE, Issue 5 2010
Osama I. El-Sabbagh
Abstract Starting from isatoic anhydrides, several new 2,3-dihydroquinazolin-4(1H)-one derivatives bearing chalcone or pyrazole or thiazole moieties at the third position were synthesized. The analgesic and anti-inflammatory activities for most compounds were studied at a dose level of 50 mg/kg via the acetic-acid-induced writhing-response method and carrageenan-induced edema method, respectively. The study showed that the chalcones bearing a 4-chlorophenyl group 4c or 4-nitrophenyl group 4b were the most active ones as analgesics. Both chalcone 4c and N -phenyl pyrazole bearing 4-methoxy phenyl group 5b showed a higher anti-inflammatory activity than celecoxib but still lower than that of diclofenac sodium. Moreover, the chalcone 4c has nearly the same ulcerogenic index as the selective cyclooxygenase-2 inhibitor celecoxib. [source]


Potential antioxidant activity of celecoxib and amtolmetin guacyl: in vitro studies

AUTONOMIC & AUTACOID PHARMACOLOGY, Issue 1 2007
M. Kirkova
Summary 1,In vitro studies of the potential antioxidant activity of the selective cyclo-oxygenase-2 inhibitor celecoxib and the non-steroid anti-inflammatory drug amtolmetin guacyl (AMG) were carried out. The study included experiments on the ability of these drugs to affect some indices of the oxidative stress [lipid peroxidation (LP), activity of antioxidant enzymes, glutathione (GSH) level] in rat stomach and colon mucosa and in liver. 2,Celecoxib and AMG did not change the activity of the enzymes GSH-peroxidase, oxidased glutathione (GSSG)-reductase and glucose-6-phosphate-dehydrogenase, as well as the GSH level in all tissue preparations. An increased superoxide dismutase (SOD) activity and a tendency to a decreased Fe/ascorbic acid-induced LP in stomach and colon mucosa were found, but only in the presence of AMG. 3,In the liver, both celecoxib and AMG decreased spontaneous and Fe/ascorbic acid-induced LP. SOD activity was enhanced only in the presence of AMG. 4,Experiments aimed at studying celecoxib and AMG in free oxygen radical-generating systems were also carried out. AMG and tolmetin (the main metabolite of AMG) inhibited OH, -provoked deoxyribose degradation in a Fenton system. Celecoxib had no effect on free radicals when tested in the same system. 5,In conclusion, the results of the present in vitro studies suggest that AMG and celecoxib possess antioxidant and metal-chelating abilities, which might contribute to their beneficial effects. [source]


Detection of Overexpressed COX-2 in Precancerous Lesions of Hamster Pancreas and Lungs by Molecular Imaging: Implications for Early Diagnosis and Prevention

CHEMMEDCHEM, Issue 6 2006
Hildegard
Abstract The enzyme cyclooxygenase-2 (COX-2) is overexpressed in many cancers, cardiovascular disease, neurodegenerative disorders, and arthritis. Selective inhibitors of COX-2 have been developed as therapeutics or preventive agents for these diseases. However, recent reports have revealed a significant increase in cardiovascular mortality in long-term users of the COX-2 inhibitors Vioxx and Celebrex, emphasizing the need for noninvasive tests that allow the identification of individuals whose COX-2 levels are overexpressed prior to assignment to treatment with these drugs. In this study, we have prepared a radioiodinated analogue of the selective COX-2 inhibitor celecoxib, and verified its binding to the COX-2 enzyme in,vitro. Biodistribution studies in hamsters demonstrated significantly higher levels of radiotracer in animals treated with the tobacco carcinogen NNK in lung, pancreas, and liver. Assessment of COX-2 levels by whole-body planar nuclear imaging two hours after injection of the radiotracer was suggestive of a distinct increase in COX-2 in the pancreas and liver of a hamster treated for 10 weeks with NNK, in the lungs and liver of a second animal, and in the liver only, in two additional animals from the same treatment group. Immunostains showed selective overexpression of COX-2 in pre-neoplastic lesions of the pancreas and lungs in only those animals that showed tracer accumulation in these organs and in the livers of all NNK-treated hamsters. Immunostains for COX-1 yielded detectable reactions in the intestinal epithelium but not in pancreas, lungs, or liver, supporting the specificity of the tracer for COX-2. Our data provide proof of principle for the hypothesis that molecular imaging with radiolabeled COX-2 inhibitors can be used for the noninvasive monitoring of overexpressed COX-2 levels. [source]