Effects Of Cyclooxygenase Inhibitors Research Articles

In vitro Screening of 5-LOX /COX-2 Dual Inhibitors from selected Medicinal plant Maytenus arbutifolia

Background: The clinical management of the inflammatory diseases by using NSAIDs and selective COX-2 inhibitors, shunting arachidonic acid pathway to the 5‐LOX pathway, which is associated with the production of high amount of Leukotrienes and cysteinyl-leukotrienes, which are involved in pathophysiological of various type of cancers and inflammatory diseases. The substantial efforts are being made to the development of dual inhibitors against Cyclooxygenase (COX-2) and 5- Lipoxygenase (5-LOX) should be more growing demand for efficient as anti-inflammatory medicine with lower side effects than the currently available drugs. Maytenus arbutifolia (M. arbutifolia) is medicinal plant belongs to the family Celastraceae, and the leaves of M.arbutifolia have been used for the treatment of skin infections and inflammatory related disease. Objective: The current study aimed to examine the in vitro screening of M. arbutifolia leaf organic extracts for the development of anti-inflammatory agents through evaluate the inhibitory effect on Cyclooxygenase- 1and2 and 5- Lipoxygenases enzymes. Methods: The powdered dried leaves of the M. arbutifolia (100 g) was extracted with successive Soxhlet extraction by using solvents of low polarity (Petroleum ether) to a high polar solvent (Ethanol). These leaf extracts were evaluated for the in vitro anti-inflammatory activity by 5- Lipooxygenase, Cyclooxygenase-1 and Cyclooxygenase-2 inhibitory activities by ELISA method. Results: Among the tested extracts, the ethanolic leaf extracts of M.arbutifolia showed (MALET) potential 5-LOX inhibition i.e.77.58 % at 100µg/ml with IC50 of 23.76µg/ml, and also exhibited two fold COX-2 versus COX-1 inhibition, with potent COX-2 inhibitory effect with IC50 of 30.35μg/ml. The promising anti-inflammatory activity exhibited by MALET was due to the presence of secondary metabolites such as flavonoids, tannins and polyphenolic compounds. Conclusion: The current study concluded that ethanolic leaf extracts of M.arbutifolia is a promising source for isolation of 5-LOX and COX-2 dual inhibitory compound and highlights the potential traditional remedies for managing of inflammatory related diseases and cancers.

New pyrazolyl-thiazolidinone/thiazole derivatives as celecoxib/dasatinib analogues with selective COX-2, HER-2 and EGFR inhibitory effects: design, synthesis, anti-inflammatory/anti-proliferative activities, apoptosis, molecular modelling and ADME studies

Two new series of pyrazolyl-thiazolidinone/thiazole derivatives 16a–b and 18a–j were synthesised, merging the scaffolds of celecoxib and dasatinib. Compounds 16a, 16b and 18f inhibit COX-2 with S.I. 134.6, 26.08 and 42.13 respectively (celecoxib S.I. = 24.09). Compounds 16a, 16b, 18c, 18d and 18f inhibit MCF-7 with IC50 = 0.73–6.25 μM (dasatinib IC50 = 7.99 μM) and (doxorubicin IC50 = 3.1 μM) and inhibit A549 with IC50 = 1.64–14.3 μM (dasatinib IC50 = 11.8 μM and doxorubicin IC50 = 2.42 μM) with S.I. (F180/MCF7) of 33.15, 7.13, 18.72, 13.25 and 8.28 respectively higher than dasatinib (4.03) and doxorubicin (3.02) and S.I. (F180/A549) of 14.75, 12.96, 4.16, 7.07 and 18.88 respectively higher than that of dasatinib (S.I. = 2.72) and doxorubicin (S.I = 3.88). Derivatives 16a, 18c, 18d, 18f inhibit EGFR and HER-2 IC50 for EGFR of 0.043, 0.226, 0.388, 0.19 μM respectively and for HER-2 of 0.032, 0.144, 0.195, 0.201 μM respectively.

Differential roles of cyclooxygenase enzymes in the regulation of murine juvenile undifferentiated spermatogonia.

Acetaminophen and ibuprofen are widely administered to babies due to their presumed safety as over-the-counter drugs. However, no reports exist on the effects of cyclooxygenase inhibitors on undifferentiated spermatogonia and spermatogonial stem cells. Infancy represents a critical period for spermatogonial stem cell formation and disrupting spermatogonial stem cells or their precursors may be associated with infertility and testicular cancer formation. The goal of this study was to examine the molecular and functional impact of cyclooxygenase inhibition and silencing on early steps of undifferentiated spermatogonia (u spg) and spermatogonial stem cell development, to assess the potential reproductive risk of pharmaceutical cyclooxygenase inhibitors. The effects of cyclooxygenase inhibition were assessed using the mouse C18-4 undifferentiated juvenile spermatogonial cell line model, previously shown to include cells with spermatogonial stem cell features, by measuring prostaglandins, cell proliferation, and differentiation, using cyclooxygenase 1- and cyclooxygenase 2-selective inhibitors NS398, celecoxib, and FR122047, acetaminophen, and ibuprofen. Cyclooxygenase 1 gene silencing was achieved using a stable short-hairpin RNA approach and clone selection, then assessing gene and protein expression in RNA sequencing, quantitative real-time polymerase chain reaction, and immunofluorescence studies. Cyclooxygenase 2 inhibitors NS398 and celecoxib, as well as acetaminophen, but not ibuprofen, dose-dependently decreased retinoic acid-induced expression of the spg differentiation gene Stra8, while NS398 decreased the spg differentiation marker Kit, suggesting that cyclooxygenase 2 is positively associated with spg differentiation. In contrast, short-hairpin RNA-based cyclooxygenase 1 silencing in C18-4 cells altered cellular morphology and upregulated Stra8 and Kit, implying that cyclooxygenase 1 prevented spg differentiation. Furthermore, RNA sequencing analysis of cyclooxygenase 1 knockdown cells indicated the activation of several signaling pathways including the TGFb, Wnt, and Notch pathways, compared to control C18-4 cells. Notch pathway genes were upregulated by selective cyclooxygenase inhibitors, acetaminophen and ibuprofen. We report that cyclooxygenase 1 and 2 differentially regulate undifferentiated spermatogonia/spermatogonial stem cell differentiation. Cyclooxygenases regulate Notch3 expression, with the Notch pathway targeted by PGD2. These data suggest an interaction between the eicosanoid and Notch signaling pathways that may be critical for the development of spermatogonial stem cells and subsequent spermatogenesis, cautioning about using cyclooxygenase inhibitors in infants.

Decreased cyclooxygenase-2 associated with impaired megakaryopoiesis and thrombopoiesis in primary immune thrombocytopenia

BackgroundCyclooxygenase (COX)-2 is a rate-limiting enzyme in the biosynthesis of prostanoids, which is mostly inducible by inflammatory cytokines. The participation of COX-2 in the maturation of megakaryocytes has been reported but barely studied in primary immune thrombocytopenia (ITP).MethodsThe expressions of COX-2 and Caspase-1, Caspase-3 and Caspase-3 p17 subunit in platelets from ITP patients and healthy controls (HC), and the expressions of COX-2 and CD41 in bone marrow (BM) of ITP patients were measured and analyzed for correlations. The effects of COX-2 inhibitor on megakaryopoiesis and thrombopoiesis were assessed by in vitro culture of Meg01 cells and murine BM-derived megakaryocytes and in vivo experiments of passive ITP mice.ResultsThe expression of COX-2 was decreased and Caspase-1 and Caspase-3 p17 were increased in platelets from ITP patients compared to HC. In platelets from ITP patients, the COX-2 expression was positively correlated with platelet count and negatively correlated to the expression of Caspase-1. In ITP patients BM, the expression of CD41 was positively correlated with the expression of COX-2. COX-2 inhibitor inhibited the count of megakaryocytes and impaired the maturation and platelet production in Meg01 cells and bone marrow-derived megakaryocytes. COX-2 inhibitor aggravated thrombocytopenia and damaged megakaryopoiesis in ITP murine model.ConclusionCOX-2 plays a vital role in the physiologic and pathologic conditions of ITP by intervening the survival of platelets and impairing the megakaryopoiesis and thrombopoiesis of megakaryocytes.

Effect of cyclooxygenase inhibition on thermal hyperemia in skeletal muscle of humans

Acute heat exposure increases skeletal muscle blood flow in humans. However, the vasodilator mechanisms mediating this hyperemic response remain unknown. The cyclooxygenase pathway is active in skeletal muscle, is heat sensitive, and contributes to cutaneous vasodilation during heat exposure in young healthy humans. Therefore, the purpose of this investigation was to test the hypothesis that inhibition of cyclooxygenase via high dose ingestion of ibuprofen would attenuate blood flow in the vastus lateralis muscle during localized heating. Four participants (26 ± 2 yrs) were studied on two separate occasions: 1) time control; 2) ingestion of 800 mg ibuprofen, a non-selective cyclooxygenase inhibitor. Experiments were randomized, counter-balanced, and separated by at least 10 days. Microdialysis was utilized to bypass the cutaneous circulation and directly measure local blood flow in the vastus lateralis muscle of each leg via the ethanol washout technique. Pulsed short-wave diathermy was used to induce deep heating of the vastus lateralis for 90 min, whereas the contralateral leg served as a thermoneutral control. Local muscle temperature was measured within ~1-2 cm of each microdialysis probe via a thermocouple. Temperature of the vastus lateralis measured through 90 min of heating did not differ between conditions (control, 39.2 ± 1.0 °C; ibuprofen, 39.7 ± 1.0 °C; P = 0.6 for interaction). Interestingly, local blood flow increased during heat exposure, but did not differ between control (baseline, 15 ± 11 mL· min-1 · 100g-1; 30 min, 23 ± 12 mL· min-1 · 100g-1; 60 min, 25 ± 12 mL· min-1 · 100g-1; 90 min, 38 ± 12 mL· min-1 · 100g-1) and ibuprofen (baseline, 14 ± 11 mL· min-1 · 100g-1; 30 min, 29 ± 12 mL· min-1 · 100g-1; 60 min, 32 ± 12 mL· min-1 · 100g-1; 90 min, 53 ± 12 mL· min-1 · 100g-1; P = 0.2 for interaction) conditions. Muscle temperature and local blood flow did not differ between conditions or across time for the thermoneutral leg (both P > 0.3). Taken together, cyclooxygenase-derived vasodilator prostanoids do not appear to contribute to thermal hyperemia in skeletal muscle of young healthy humans. This work was supported by grants from the National Institutes of Health (T32 AG020494; R01AG059314) and the American Heart Association (TPA958179). This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Effects of COX 1-2 Inhibitors on Prevention of Rocuronium Injection Pain: Controlled, Randomised, Double Blind Study

Aim: Rocuronium bromide is a painful agent during induction of general anaesthesia. The aim of the study is to investigate the effects of Cyclooxygenase (COX) inhibitors as a resque agent against the rocuronium pain.
 Material and Methods: Sixty patients of either sex scheduled for under general anesthesia were enrolled in this study. Patients were allocated into two groups (Group 1: Dexkethoprofen group, Group 2: Control group). Pain was evaluated by during rocuronium injection, patients were scored by a scale showed below. 0; No movement response to injection, 1; Mild movement response to injection, 2; Hand withdrawal response to injection, 3; Arm withdrawal response to injection. We also evaluated the pain with 2 questions when the patient was in the recovery room. Question 1. What was the last feeling before you fall into sleep? and question 2. Did you feel any pain on your hand during medication injection for anesthesia?
 Results: There were differences between the groups in terms of total pain score for example in group 1 there were 16 (53%) patients who did not make any movement during rocuronium injection while there were 22 (73%) patients in group 2.There was significant difference in injection rocuronium bromide pain between group 1: dexkethoprofen group, Group 2: control group in terms of the answer to the second question. Patients felt less pain than the control group. In the second question, 16% in group 2 stated that they felt pain, while this rate was observed as 3% in group 1.
 Conclusion: The effect of cox inhibitors on rocuronium pain was seen in our study but control group is also effective in reducing pain in vascular width.

Effect of Cyclooxygenase Inhibition on Peripheral Venous Distension Reflex in Healthy Humans.

Peripheral venous distension evokes a pressor reflex (venous distension reflex). Afferent group III and IV nerves innervating veins are suggested as the afferent arm of the venous distension reflex. Prostaglandins stimulate/sensitize group III/IV nerves. We hypothesized that inhibition of prostaglandin synthesis by local cyclooxygenase blockade would attenuate the muscle sympathetic nerve activity (MSNA) and blood pressure responses to venous distension. Nineteen healthy volunteers (age, 27±5 years) participated in the study with 2 visits. To induce venous distension, a volume of solution (saline alone or 9 mg ketorolac tromethamine in saline) was infused into the vein in the antecubital fossa of an arterially occluded forearm. During the procedure, beat-by-beat heart rate, blood pressure and MSNA were recorded simultaneously. The vein size was measured with ultrasound. In both visits, the venous distension procedure significantly increased blood pressure, heart rate, and MSNA (all, P<0.05). The increase in mean arterial pressure and MSNA in the ketorolac visit was significantly lower than in the control visit (∆ mean arterial pressure, 7.0±6.2 versus 13.8±7.7 mm Hg; ∆MSNA, 6.0±7.1 versus 14.8±7.7 bursts/min; both, P<0.05). The increase in vein size induced by the infusion was not different between visits. The presented data show that cyclooxygenase blockade attenuates the responses in MSNA and blood pressure to peripheral venous distension reflex. The results suggest that cyclooxygenase products play a key role in evoking afferent activation responsible for the venous distension reflex.

Effect of Cyclooxygenase Inhibition on P-Glycoprotein Expression and Phenytoin Level in Brain Tissue of Pilocarpine Induced Epilepsy in Rats

Effect of Cyclooxygenase Inhibition on P-Glycoprotein Expression and Phenytoin Level in Brain Tissue of Pilocarpine Induced Epilepsy in Rats

From tryptamine to the discovery of efficient multi-target directed ligands against cholinesterase-associated neurodegenerative disorders.

A novel class of benzyl-free and benzyl-substituted carbamylated tryptamine derivatives (CDTs) was designed and synthesized to serve as effective building blocks for the development of novel multi-target directed ligands (MTDLs) for the treatment of neurological disorders linked to cholinesterase (ChE) activity. The majority of them endowed butyrylcholinesterase (BuChE) with more substantial inhibition potency than acetylcholinesterase (AChE), according to the full study of ChE inhibition. Particularly, hybrids with dibenzyl groups (2b-2f, 2j, 2o, and 2q) showed weak or no neuronal toxicity and hepatotoxicity and single-digit nanomolar inhibitory effects against BuChE. Through molecular docking and kinetic analyses, the potential mechanism of action on BuChE was first investigated. In vitro H2O2-induced HT-22 cells assay demonstrated the favorable neuroprotective potency of 2g, 2h, 2j, 2m, 2o, and 2p. Besides, 2g, 2h, 2j, 2m, 2o, and 2p endowed good antioxidant activities and COX-2 inhibitory effects. This study suggested that this series of hybrids can be applied to treat various ChE-associated neurodegenerative disorders such as Alzheimer's disease (AD) and Parkinson's disease (PD), as well as promising building blocks for further structure modification to develop efficient MTDLs.

Analysis of Caffeine-Etoricoxib Pi-Electron Stacked Complexes: a Basis for Future Parenteral Preparations

Etoricoxib, although exhibiting superior and selective anti-inflammatory properties, exhibits poor aqueous solubility which precludes its formulation into parenteral preparations. This study aims to increase the aqueous solubility of this drug by complexation with caffeine, an aromatic base known to exhibit a pi-pi stacked complex with aromatic drugs. The molar complexation between caffeine and etoricoxib was analyzed by phase solubility studies, Jacob’s continuous variation, and Ardon’s plots. Solid-state analyses and in vitro diffusion experiments were employed to analyze the optimized caffeine-etoricoxib complex (OCEC). The in vitro inhibitory properties of OCEC against cyclooxygenase 2 enzyme (COX-2) were compared to plain etoricoxib (PE). Phase solubility diagrams showed that the solubility of etoricoxib (0.25 M) was continuously elevated with increasing caffeine concentration as a result of complexation. Optimization experiments showed that caffeine complexes with etoricoxib at a 1:1 molar ratio. The effects of pH on degradation showed that etoricoxib within the OCEC is most stable at pH 7.4. The release of etoricoxib from OCEC follows super case 2 transport mechanisms with high diffusivity. In terms of in vitro inhibition against COX-2, OCEC (IC50 = 0.125 mcg/mL) is more potent than PE (IC50 = 3.1 mcg/mL). This study revealed that a 1:1 molar stacked complex between caffeine and etoricoxib drastically increases the aqueous solubility of the latter, a greater stability of the drug at pH 7.4, a Korsmeyer-Peppas diffusion kinetics involving non-Fickian drug release, and enhanced in vitro COX-2 inhibitory effects.

Anti-Inflammatory Potential of Brucea javanica Fruit

Objective: Inflammation plays a crucial role in the progression of many diseases, excessive inflammation increases immune cell activation, which can destroy tissues and body health. When inflammation occurs, multiple pro-inflammatory mediators are overproduced, leading to a variety of diseases such as rheumatism, diabetes, and cardiovascular problems. Brucea javanica has been used as traditional medicine as a therapy for anti-tumor, amebic dysentery, diarrhea, malaria, and intestinal inflammation. Therefore, in this study, we explored the effect of ethanol extract Brucea javanica Fruit on anti-inflammation activity in carrageenan-induced rat paw edema and the COX-2 inhibitory effect in vivo.&#x0D; Methods: In vivo anti-inflammatory activity of the ethanolic extracts was evaluated using the carrageenan-induced rat paws edema method at doses of 50, 100, and 200mg/kg and further investigated the effect of Cyclooxygenase-2 inhibitory using ELISA readers.&#x0D; Results: The ethanolic extract of Brucea javanica Fruit exhibited anti-inflammatory activity by oral intake of 50 mg/kg of the ethanolic extract and Brucea javanica inhibited rat paw edema by 50.91% significantly compared to Celecoxib by 58.52%. Moreover, Brucea javanica showed COX-2 inhibition by 16,40% compared to Celecoxib by 20,50%.&#x0D; Conclusions: These findings indicate that Brucae javanica Fruit extracts have promising anti-inflammatory activity directed against COX-2 enzymatic activity.&#x0D; Keywords: Anti-inflammatory, Brucea javanica, Malur, Buah Makasar, Cyclooxygenase.

Exploring multifunctional components from Andrographis paniculata by affinity ultrafiltration with three molecular targets

Andrographis paniculata (Burm. F.) Nees (AP) was a typical plant resource that has the concomitant function of both foodstuff and medicine, while the action mechanisms of its immune regulation, anti-inflammatory and anti-viral effects and the specific components remain unclear. In this work, a screening approach combining bio-affinity ultrafiltration with liquid chromatography mass spectrometry (UF-LC/MS) was hired to screen potential bioactive compounds from AP. The crude extract of AP exerted COX-2 and ACE2 inhibitory effects by other bioassays. Meanwhile, a total of eleven ligands targeting COX-2, IL-6 and ACE2 were screened out. Thereinto, two compounds including andrographolide and 14-deoxy-11,12-didehydroandrographolide exhibited strong binding affinities to COX-2, IL-6 and ACE2 by UF-LC/MS and molecular docking analysis. This is the first report to apply UF-LC/MS approach to rapidly screen out multi-target ligands from AP, and further decipher corresponding mechanisms, which could be beneficial to expedite the search for new multi-target bioactive compounds in other natural products or foods.

Cyclooxygenase-2 Upregulated by Temozolomide in Glioblastoma Cells Is Shuttled In Extracellular Vesicles Modifying Recipient Cell Phenotype.

Temozolomide (TMZ) resistance is frequent in patients with glioblastoma (GBM), a tumor characterized by a marked inflammatory microenvironment. Recently, we reported that cyclooxygenase-2 (COX-2) is upregulated in TMZ-resistant GBM cells treated with high TMZ concentrations. Moreover, COX-2 activity inhibition significantly counteracted TMZ-resistance of GBM cells. Extracellular vesicles (EV) are considered crucial mediators in orchestrating GBM drug resistance by modulating the tumor microenvironment (TME) and affecting the surrounding recipient cell phenotype and behavior. This work aimed to verify whether TMZ, at low and clinically relevant doses (5-20 µM), could induce COX-2 overexpression in GBM cells (T98G and U87MG) and explore if secreted EV shuttled COX-2 to recipient cells. The effect of COX-2 inhibitors (COXIB), Celecoxib (CXB), or NS398, alone or TMZ-combined, was also investigated. Our results indicated that TMZ at clinically relevant doses upregulated COX-2 in GBM cells. COXIB treatment significantly counteracted TMZ-induced COX-2 expression, confirming the crucial role of the COX-2/PGE2 system in TMZ-resistance. The COXIB specificity was verified on U251MG, COX-2 null GBM cells. Western blotting of GBM-EV cells showed the COX-2 presence, with the same intracellular trend, increasing in EV derived from TMZ-treated cells and decreasing in those derived from COXIB+TMZ-treated cells. We then evaluated the effect of EV secreted by TMZ-treated cells on U937 and U251MG, used as recipient cells. In human macrophage cell line U937, the internalization of EV derived by TMZ-T98G cells led to a shift versus a pro-tumor M2-like phenotype. On the other hand, EV from TMZ-T98G induced a significant decrease in TMZ sensitivity in U251MG cells. Overall, our results, in confirming the crucial role played by COX-2 in TMZ-resistance, provide the first evidence of the presence and effective functional transfer of this enzyme through EV derived from GBM cells, with multiple potential consequences at the level of TME.

Effects of Cyclooxygenase-2 Inhibitors on Gastrointestinal Malignancies: a Systematic Review and Meta-analysis.

Aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) are associated with a reduced risk of gastrointestinal malignancies, which is thought to be mediated mainly through the inhibition of cyclooxygenases-2 (COX-2). Due to the severe side effects of aspirin/NSAIDs, selective COX-2 inhibitors may be a more ideal choice. The objective is to evaluate the association of selective COX-2 inhibitors with gastrointestinal (GI) malignancies and premalignant lesions. We searched for published manuscripts evaluating the association between COX-2 inhibitors and GI malignancies or precancerous lesion. Two investigators independently abstracted the data; then, we conducted the analysis by Review Manager V.5.0; evaluation of effectiveness was performed by an intention to treat (ITT) method. Selective COX-2 inhibitors had no beneficial effects on the progression or regression of esophageal and gastric dysplasia (OR = 1.06, 95% CI 0.63-1.78, P = 0.83 for regression of esophageal dysplasia; OR = 1.06, 95% CI 0.58-1.91, P = 0.86 for progression of esophageal dysplasia; OR = 1.95, 95%CI 0.92-4.17, P = 0.08 for regression of gastric dysplasia; and OR = 0.99, 95%CI 0.68-1.43, P = 0.94 for progression of gastric dysplasia). There is no protective effect on colorectal cancer (OR = 0.89, 95% CI 0.77-1.03, P = 0.11), and the use could not improve the effect of chemoradiation (OR = 1.20, 95% CI 0.46-3.19, P = 0.71). This pooled analysis indicates no meaningful association between selective COX-2 inhibitors and GI malignancies.

Effect of Cyclooxygenase Inhibitor on Hypoxia Stimulated Cerebral Blood Flow Using Arterial Spin Labeling Magnetic Resonance

IntroductionThe purpose of this study was twofold: 1) to determine microvascular cerebral blood flow (CBF) during hypoxia and 2) to investigate the effect of Ketorolac, a cyclooxygenase (COX) inhibitor, on hypoxia stimulated CBF. Acute exposure to hypoxic conditions leads to an increase in CBF, which may be regionally specific. Studies investigating the effect of hypoxia on CBF have utilized varying gradations and durations of hypoxia and different measuring techniques (transcranial doppler ultrasound or magnetic resonance imaging (MRI)). COX has been shown to significantly contribute to CBF at rest, however during hypoxia research has shown conflicting data on COX contribution to hypoxic CBF. Utilizing arterial spin labeling (ASL), an MRI technique that provides microvascular global and regional perfusion, during hypoxia stimulated CBF and the role of COX. We hypothesized hypoxia will increase CBF non‐uniformly, and COX inhibition with Ketorolac will reduce hypoxic dilation in some, but not all brain regions.Methods6 healthy young adults subjects (24 ± 3 years, 22.4 ± 0.7 BMI, 4 male) were included in this analysis using an institutional review board (IRB)‐approved protocol. Subjects completed an ASL MRI scans (5.5 min each) under the 3 distinct conditions: normoxia, hypoxia, and hypoxia + ketorolac drug infusion. The first ASL scan occurred while the subject breathed ambient air (baseline). Isocapnic hypoxia was then induced by breathing reduced O2 (9‐13%) to reduce arterial saturation to 80‐85% for steady state hypoxia followed by the first hypoxia ASL scan. While hypoxia was maintained, Ketorolac was infused at a rate of 0.495 mg/kg over 3 minutes (average dose 33.9 ± 2.8 mg), the third ASL scan was then completed (hypoxia+ketorolac). ASL analysis included smoothing grey matter, co‐registering and normalizing raw data, brain masking and region of interest processing. Statistics were determined using a Two‐Way Repeated Measures ANOVA with Tukey’s post‐hoc analysis.ResultsData are mean ± SD. SpO2 (98 ± 1%, 82 ± 2%, 82 ± 1%) and ETCO2 (36 ± 1mmHg, 35 ± 2mmHg, 34 ± 2) at baseline, hypoxia, and hypoxia+ketorolac, respectively. Baseline Global CBF (58 ± 15 ml/100g‐1/min‐1) was not significantly different from hypoxia (61 ± 14 ml/100g‐1/min‐1) (p=0.47). Regionally, CBF between baseline and hypoxia were not different in the right/left temporal, occipital, parietal, or frontal lobes (R/L: p=0.47/p=0.98, p=0.59/p=0.49, p=0.46/p=0.63, and p=0.18/0.19, respectively). Ketorolac did not change global CBF during hypoxia (60 ± 17 ml/100g‐1/min‐1) (p=0.96). Regional CBF during hypoxia and hypoxia+ketorolac was not changed in the right/left temporal, occipital, parietal, or frontal lobes (R/L: p=0.96/0.91, p=0.57/0.88, p=0.86/0.99, and p=0.38/0.35, respectively).DiscussionContrary to our hypothesis CBF did not change globally or regionally with hypoxia stimulation. Furthermore, COX inhibition via Ketorolac did not change CBF during hypoxia in any region. This finding corroborates previous studies in animals and macrovascular flow in humans that COX inhibitor Ketorolac acts differently in the brain compared to Indomethacin, despite similar pharmacology. In conclusion, acute hypoxia exposure with Ketorolac did not alter microvascular CBF.

Effect of cyclooxygenase-2 inhibitors in double J stent removal

Background: Celecoxib is a selective cyclooxygenase-2(COX-2) inhibitor that can reduce the inflammatory process during double J (DJ) stent removal procedure. This study aimed to determine the differences in pain levels in patients undergoing DJ stent removal under local anesthesia by oral administration of celecoxib before the procedure. Materials and methods: A total of 46 male patients who underwent removal of DJ stent under local anesthesia from December 2019 to February 2020 were included. Patients were divided into two groups according to oral administration of celecoxib 3 hours before the procedure. The visual analog scale (VAS) and side effects were compared between the two groups. Results: The mean patient age was 50.26 ±14.92 years in the group without celecoxib and 50.35 ±15.61 years in the group with celecoxib. The mean intraoperative VAS score was significantly higher in the group without celecoxib (6.87 ± 1.51) than that in the group with celecoxib (3.74 ± 1.65) (p=0.04). The VAS scores on the first day after the procedure were 2.08 ±0.79 and 1.34 ± 0.98 in the groups without and with celecoxib, respectively (p=0.53). Only 1 patient had nausea as side effect of celecoxib. Conclusion: Celecoxib can reduce pain during DJ stent removal.

Efficacy and safety of cyclooxygenase 2 inhibitors for desmoid tumor management: a systematic review.

ABSTRACTThe efficacy and safety of cyclooxygenase 2 (COX2) inhibitors for the treatment of desmoid-type fibromatosis (DF) are unclear. Therefore, we systematically reviewed related literature to assess the efficacy and safety of COX2 inhibitors for DF treatment. We searched pertinent literature between January 1999 and August 2017 to identify relevant studies using the keywords “Fibromatosis, aggressive” and “Cyclooxygenase inhibitors.” Thereafter, we screened and determined the quality of the studies using the Grading of Recommendations Assessment, Development, and Evaluation system and extracted the article data. The critical outcomes selected were the efficacy and adverse effects of COX2 inhibitors. Efficacy was evaluated in terms of clinical benefit when patients showed complete response, partial response, and stable disease. Thirty-one articles were identified from the database search, and one was identified through the reviewers’ manual search. Finally, we retrieved six studies, including three case reports, comprising 89 patients after the first and second screenings. Fifty-three patients were excluded because three studies were reported from the same institution; hence, in total, 36 patients were included. Clinical benefit was noted in 64% of the patients. Three adverse effects were identified from the records of the six extracted studies. The strategy of watchful waiting using COX2 inhibitors with few side effects is weakly recommended for DF, especially DF patients with pain.

Assessment of cytotoxic effects of new derivatives of pyrazino[1,2-a] benzimidazole on isolated human glioblastoma cells and mitochondria

AimsGlioblastoma multiforme (GBM) is a highly devastating malignant brain tumor with poor pharmacotherapy. Based on COX-2 inhibitory effects in preventing cancer progression, new pyrazino[1,2-a]benzimidazole derivatives were assessed on isolated human GBM cells. Main methodsIn this study, firstly, primary culture of astrocytes from human GBM samples was prepared and exposed to 2,6-dimethyl pyrazino[1,2-a]benzimidazole (L1) and 3,4,5-trimethoxy pyrazino[1,2-a]benzimidazole (L2) for finding their half-maximal inhibitory concentration (IC50). In the following, in two phases, cell apoptosis pathway and mitochondrial markers were investigated on GBM and also HEK293 cells (as non-cancerous normal cells). Key findingsThe MTT results represented a remarkable selective cytotoxic effect of both L1 and L2 on GBM cells, and interestingly not on normal cells. After 48 h, IC50 of L1 and L2 were calculated as 13 μM and 85 μM, respectively. Annexin/PI staining showed that L1 and L2 induce apoptosis in GBM cells, and caspase measurement showed that apoptosis occurs through mitochondrial signaling. In the clonogenic assay, GBM cells formed more paraclones and fewer holoclones after treating with L1 and L2. L1 and L2 also selectively enhanced mitochondrial damaged markers, including reactive oxygen species (ROS) formation, and mitochondrial swelling, decreased mitochondrial membrane potential (MMP) and cytochrome c release in isolated cancerous GBM mitochondria. SignificanceOur findings on human primary astrocyte cells illustrated that L1 and L2 compounds, with COX-2 inhibitory effect, through the intrinsic pathway of apoptosis concerning mitochondrial damage enhancement have therapeutic potentials on GBM.

Production, structural and biochemical characterization relevant to antitumor property of acidic exopolysaccharide produced from Bacillus sp. NRC5

This study targeted the production of exopolysaccharide from Bacillus sp. NRC5 grown in Egyptian seawater to use it as natural antitumor therapy. The biological activities of selected exopolysaccharide (BEPS) as an antioxidant, anti-inflammatory and anticancer have been studied. BEPS was evaluated as an anti-inflammatory in vitro against cyclooxygenase (COX-1 and COX-2) and evaluated as an anticancer on human breast and prostate cancer cell lines (MCF-7 and PC3). In addition, BEPS antitumor activity was tested against the Ehrlich Ascites Carcinoma (EAC) model. The BEPS presented potent antioxidant activities, consisted of glucose, mannose, and mannuronic acid in a molar ratio of 1.0:1.7:0.8 with a molecular weight of 3.59 × 105g/mol. BEPS showed a promising COX-2 inhibitory effect in comparison with the reference drug celecoxib. BEPS appeared efficient anticancer property, where it killed 64.20 and 70.20% of MCF-7 and PC3 cells at 100µg/ml, respectively (IC50, 76.70, and 70.40µg/ml, respectively). BEPS exhibited antitumor ability as it prolonged the lifespan of mice to reach 75days instead of 20days in the tumor control, reduced viable cancer cells count, tumor volume and weight, modulated blood components, and white blood cells differentiation. BEPS produced from Bacillus sp. NRC5 showed its antioxidant and anti-inflammatory abilities and antitumor abilities, which may all be attributed to its unique composition containing sulfated moieties and uronic acids.

Basic Pharmacological Characterization of EV-34, a New H2S-Releasing Ibuprofen Derivative.

Background: Cardioprotective effects of H2S are being suggested by numerous studies. Furthermore, H2S plays a role in relaxation of vascular smooth muscle, protects against oxidative stress, and modulates inflammation. Long-term high-dose use of NSAIDs, such as ibuprofen, have been associated with enhanced cardiovascular risk. The goal of the present work is the synthesis and basic pharmacological characterization of a newly designed H2S-releasing ibuprofen derivative. Methods: Following the synthesis of EV-34, a new H2S-releasing derivative of ibuprofen, oxidative stability assays were performed (Fenton and porphyrin assays). Furthermore, stability of the molecule was studied in rat serum and liver lysates. H2S-releasing ability of the EC-34 was studied with a hydrogen sulfide sensor. MTT (3-(4,5-dimethylthiazol 2-yl)-2,5-(diphenyltetrazolium bromide)) assay was carried out to monitor the possible cytotoxic effect of the compound. Cyclooxygenase (COX) inhibitory property of EV-34 was also evaluated. Carrageenan assay was carried out to compare the anti-inflammatory effect of EV-34 to ibuprofen in rat paws. Results: The results revealed that the molecule is stable under oxidative condition of Fenton reaction. However, EV-34 undergoes biodegradation in rat serum and liver lysates. In cell culture medium H2S is being released from EV-34. No cytotoxic effect was observed at concentrations of 10, 100, 500 µM. The COX-1 and COX-2 inhibitory effects of the molecule are comparable to those of ibuprofen. Furthermore, based on the carrageenan assay, EV-34 exhibits the same anti-inflammatory effect to that of equimolar amount of ibuprofen (100 mg/bwkg). Conclusion: The results indicate that EV-34 is a safe H2S releasing ibuprofen derivative bearing anti-inflammatory properties.