Long-term intermittent oral administration of selective COX-2 inhibitor improved the clinical outcomes of COVID-19 in patients with cirrhosis.

OBJECTIVES: Patients with cirrhosis are more susceptible to coronavirus disease 2019 (COVID-19) due to immune dysfunction. In this retrospective study we aimed to investigate whether suppression of mild systemic inflammation with selective cyclooxygenase-2 inhibitor (COX-2-I) during chronic care of cirrhotic patients would reduce the occurrence of acute decompensated events and improve patient prognosis of COVID-19. METHODS: Medical records of cirrhotic patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection were sequentially reviewed. The patients were divided into the COX-2-I and control groups depending on whether they took oral selective COX-2-I for over 3 months or not. The primary outcomes included the occurrence of severe/critical COVID-19, acute decompensated events, and acute-on-chronic liver failure (ACLF). RESULTS: After propensity score matching analysis, there were 314 cases in the control group and 118 cases in the COX-2-I group. Compared with the control group, the risk of severe/critical COVID-19 in the COX-2-I group was significantly decreased by 83.1% (p = 0.004). Acute decompensated events and ACLF occurred in 23 (7.32%) and nine (2.87%) cases in the control group, but none in the COX-2-I group (p = 0.003 and 0.122). The rate of hospitalization in the COX-2-I group was significantly lower than that of the control group (3.39% vs 13.06%, p = 0.003). No patient in the COX-2-I group required intensive care unit admission. CONCLUSIONS: Long-term intermittent oral administration of selective COX-2-I in cirrhotic patients significantly reduces the occurrence of severe/critical COVID-19, acute decompensated events, and ACLF. It may also be used for systemic inflammation caused by other pathogens.

TLR2 promotes traumatic deep venous thrombosis of the lower extremity following femoral fracture by activating the NF­κB/COX­2 signaling pathway in rats.

Endothelial cells (ECs) are crucial for maintaining the integrity of blood vessel walls and reducing thrombosis. Deep venous thrombosis (DVT) is a common thrombotic disease and its diagnosis and treatment remain at the stage of coagulation function examination and post-onset treatment. Thus, identifying the pathogenesis of DVT is important. The present study investigated the significance of the Toll-like receptor 2 (TLR2)/nuclear factor kappa B (NF-κB)/cyclooxygenase-2 (COX-2) signaling pathway in a human umbilical vein EC (HUVECs) oxygen glucose deprivation (OGD) model and femoral fractures were induced in anesthetized rats using a quantifiable impact device delivering 5 J of energy to each side of the proximal outer thigh, followed by external fixation with a hip spica cast to create a traumatic deep venous thrombosis (TDVT) animal model. Rats were subjected to quantitative impact fixation to establish a TDVT model. The rats were treated with a TLR2 agonist (Pam3CSK4) and a TLR2 inhibitor (C29) via intraperitoneal injection and thrombus formation was examined. HUVECs were subjected to OGD and treated with Pam3CSK4 or C29 and cell viability and apoptosis were assessed. Western blotting, immunofluorescence and reverse transcription-quantitative PCR were used to examine the inflammatory responses and signaling pathways. In vivo experiments showed that Pam3CSK4 promoted thrombus formation and increased the mRNA and protein expression of NF-κB, COX-2, Tissue factor (TF), IL-6 and P-selectin compared with the model and C29 groups. In vitro experiments showed that Pam3CSK4 treatment resulted in a higher number of apoptotic cells than C29 treatment and that it increased the levels of NF-κB, COX-2, IL-6 and P-selectin, whereas C29 decreased them. Thus, TLR2 promotes the inflammatory response in EC through the NF-κB/COX-2 signaling pathway, which may lead to EC apoptosis and the occurrence of TDVT.

Piperine exerts anti-inflammatory effects and antagonises the properties of celecoxib and ketoprofen: in vivo and molecular docking studies.

This study evaluates the anti-inflammatory effects of a natural product, piperine (PPN), using in vivo and in silico methodologies. In the in vivo segment, inflammation was induced in the right hind paw of young chicks via a formalin (50 µL) injection. PPN was orally administered at doses of 25 and 50 mg/kg with or without celecoxib (CXB) and/or ketoprofen (KPN) (42 mg/kg). The vehicle acted as the negative control group (NC). The in silico analysis predicted the drug-likeness, pharmacokinetics, and toxicity profile of PPN, along with evaluating its binding affinity and ligand-receptor interactions. Results indicate that PPN significantly (p < 0.05) reduced licking frequency and paw edoema in a dose-dependent manner. However, in combination therapy, PPN diminished the effects of both CXB and KPN. PPN showed high affinity (-8.6 kcal/mol) towards the COX-2 enzyme. Therefore, PPN exerts anti-inflammatory effects in chicks through COX-2 inhibition pathways and antagonises CXB and KPN activities.

Modeling enzyme competition in Eicosanoid metabolism in macrophage cells using a cybernetic framework.

Cellular metabolism is a complex process involving the consumption and production of metabolites, as well as the regulation of enzyme synthesis and activity. Modeling of metabolic processes is important to understand the underlying mechanisms, with a wide range of applications in metabolic engineering and health sciences. Cybernetic modeling is a powerful technique that accounts for unknown intricate regulatory mechanisms in complex cellular processes. It models regulation as goal-oriented, where the levels and activities of enzymes are modulated by the cybernetic control variables to achieve the cybernetic objective. This study employed cybernetic model to study the enzyme competition between arachidonic acid (AA) and eicosapentaenoic acid (EPA) metabolism in murine macrophages. AA and EPA compete for the shared enzyme cyclooxygenase (COX). Upon external stimuli, AA produces pro-inflammatory 2-series prostaglandins (PGs) and EPA metabolizes to anti-inflammatory 3-series PGs, where pro- and anti- inflammatory responses are necessary for homeostasis. The cybernetic model adequately captured the experimental data for control and EPA-supplemented conditions. The model is validated by performing an F-test, conducting leave-one-out-metabolite cross-validation, and predicting an unseen experimental condition. The cybernetic variables provide insights into the competition between AA and EPA for the COX enzyme. Predictions from our model suggest that the system undergoes a switch from a predominantly pro-inflammatory state in the control to an anti-inflammatory state with EPA-supplementation. The model can also be used to analytically determine the AA and EPA concentrations required for the switch to occur. The quantitative outcomes enhance understanding of pro- and anti-inflammatory metabolism in RAW 264.7 macrophages.

Indomethacin inhibits human seasonal coronaviruses at late stages of viral replication in lung cells: Impact on virus-induced COX-2 expression.

Coronaviruses (CoV), zoonotic viruses periodically emerging worldwide, represent a constant potential threat to humans. To date, seven human coronaviruses (HCoV) have been identified: HCoV-229E, HCoV-NL63, HCoV-OC43 and HCoV-HKU1, globally circulating in the human population (seasonal coronaviruses, sHCoV), and three highly-pathogenic coronaviruses, SARS-CoV, MERS-CoV and SARS-CoV-2. Although sHCoV generally cause only mild respiratory diseases, severe complications may occur in specific populations, highlighting the need for broad-spectrum anti-coronavirus drugs. Herein we show that indomethacin (INDO), a non-steroidal anti-inflammatory drug widely used in the clinic for its potent anti-inflammatory and analgesic properties, effectively inhibits the replication of Alpha-coronavirus HCoV-229E and Beta-coronavirus HCoV-OC43 in human lung-derived cells. Indomethacin does not interfere with HCoV binding or entry into target cells, but acts at late stages of the virus life cycle, inhibiting viral RNA synthesis and infectious viral particles production. Although INDO anti-inflammatory action is mediated by blocking cyclooxygenase-1 and -2 (COX-1/2) enzymatic activity, the antiviral effect appears to be cyclooxygenase-independent and is not mimicked by the potent COX-1/2 inhibitor aspirin. Interestingly we found that both seasonal HCoVs markedly (>100 fold) induce the expression of the pro-inflammatory mediator COX-2 in lung cells; notably, INDO-treatment was found to effectively inhibit virus-induced COX-2 expression at the transcriptional level, revealing an additional mechanism to prevent COX-2-mediated inflammatory reactions in HCoV-infected lung cells, besides COX activity inhibition. Altogether the results indicate that indomethacin, possessing both potent anti-inflammatory properties and a direct antiviral activity against HCoV, could be effective in the treatment of Alpha- and Beta-coronavirus infections.

Prostaglandin E2 signaling through prostaglandin E receptor subtype 2 and Nurr1 induces fibroblast growth factor 23 production.

Bone cells produce fibroblast growth factor 23 (FGF23), a hormone regulating renal phosphate and vitamin D homeostasis, and a paracrine factor produced in further tissues. Chronic kidney disease and cardiovascular disorders are associated with early elevations of plasma FGF23 levels associated with clinical outcomes. FGF23 production is dependent on many conditions including inflammation. Prostaglandin E2 (PGE2) is a major eicosanoid with a broad role in pain, inflammation, and fever. Moreover, it regulates renal blood flow, renin secretion, natriuresis as well as bone formation through prostaglandin E receptor 2 (EP2). Here, we studied the role of PGE2 and its signaling for the production of FGF23. Osteoblast-like UMR-106 cells were exposed to EP receptor agonists, antagonists or RNAi. Wild type and EP2 knockout mice were treated with stable EP2 agonist misoprostol. Fgf23 or Nurr1 gene expression was determined by quantitative real-time PCR, hormone and further blood parameters by enzyme-linked immunosorbent assay and colorimetric methods. PGE2 and EP2 agonists misoprostol and butaprost enhanced FGF23 production in UMR-106 cells, effects mediated by EP2 and transcription factor Nurr1. A single dose of misoprostol up-regulated bone Fgf23 expression and FGF23 serum levels in wild type mice with subtle effects on parameters of mineral metabolism only. Compared to wild type mice, the FGF23 effect of misoprostol was significantly lower in EP2-deficient mice. To conclude, PGE2 signaling through EP2 and Nurr1 induces FGF23 production. Given the broad physiological and pathophysiological implications of PGE2 signaling, this effect is likely of clinical relevance.

Potential of Coffee Cherry Pulp Extract against Polycyclic Aromatic Hydrocarbons in Air Pollution Induced Inflammation and Oxidative Stress for Topical Applications.

Airborne particulate matter (PM) contains polycyclic aromatic hydrocarbons (PAHs) as primary toxic components, causing oxidative damage and being associated with various inflammatory skin pathologies such as premature aging, atopic dermatitis, and psoriasis. Coffee cherry pulp (CCS) extract, rich in chlorogenic acid, caffeine, and theophylline, has demonstrated strong antioxidant properties. However, its specific anti-inflammatory effects and ability to protect macrophages against PAH-induced inflammation remain unexplored. Thus, this study aimed to evaluate the anti-inflammatory properties of CCS extract on RAW 264.7 macrophage cells exposed to atmospheric PAHs, compared to chlorogenic acid (CGA), caffeine (CAF), and theophylline (THP) standards. The CCS extract was assessed for its impact on the production of nitric oxide (NO) and expression of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2). Results showed that CCS extract exhibited significant antioxidant activities and effectively inhibited protease and lipoxygenase (LOX) activities. The PAH induced the increase in intracellular reactive oxygen species, NO, TNF-α, IL-6, iNOS, and COX-2, which were markedly suppressed by CCS extract in a dose-dependent manner, comparable to the effects of chlorogenic acid, caffeine, and theophylline. In conclusion, CCS extract inhibits PAH-induced inflammation by reducing pro-inflammatory cytokines and reactive oxygen species (ROS) production in RAW 264.7 cells. This effect is likely due to the synergistic effects of its bioactive compounds. Chlorogenic acid showed strong antioxidant and anti-inflammatory activities, while caffeine and theophylline enhanced anti-inflammatory activity. CCS extract did not irritate the hen's egg chorioallantoic membrane. Therefore, CCS extract shows its potential as a promising cosmeceutical ingredient for safely alleviating inflammatory skin diseases caused by air pollution.

Insights from pharmacovigilance and pharmacodynamics on cardiovascular safety signals of NSAIDs.

Background and Aim: Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used to treat fever, pain, and inflammation. Concerns regarding their cardiovascular safety have been raised. However, the underlying mechanism behind these events remains unknown. We aim to investigate the cardiovascular safety signals and receptor mechanisms of NSAIDs, employing a comprehensive approach that integrates pharmacovigilance and pharmacodynamics. Methods: This study utilized a pharmacovigilance-pharmacodynamic approach to evaluate the cardiovascular safety of NSAIDs and explore potential receptor mechanisms involved. Data were analyzed using the OpenVigil 2.1 web application, which grants access to the FDA Adverse Event Reporting System (FAERS) database, in conjunction with the BindingDB database, which provides target information on the pharmacodynamic properties of NSAIDs. Disproportionality analysis employing the Empirical Bayes Geometric Mean (EBGM) and Reporting Odds Ratio (ROR) methods was conducted to identify signals for reporting cardiovascular-related adverse drug events (ADEs) associated with 13 NSAIDs. This analysis encompassed three System Organ Classes (SOCs) associated with the cardiovascular system: blood and lymphatic system disorders, cardiac disorders, and vascular disorders. The primary targets were identified through the receptor-NSAID interaction network. Ordinary least squares (OLS) regression models explored the relationship between pharmacovigilance signals and receptor occupancy rate. Results: A total of 201,231 reports of cardiovascular-related ADEs were identified among the 13 NSAIDs. Dizziness, anemia, and hypertension were the most frequently reported Preferred Terms (PTs). Overall, nimesulide and parecoxib exhibited the strongest signal strengths of ADEs at SOC levels related to the cardiovascular system. On the other hand, our data presented naproxen and diclofenac as drugs of comparatively low signal strength. Cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) were identified as central targets. OLS regression analysis revealed that the normalized occupancy rate for either COX-1 or COX-2 was significantly inversely correlated with the log-transformed signal measures for blood and lymphatic system disorders and vascular disorders, and positively correlated with cardiac disorders and vascular disorders, respectively. This suggests that higher COX-2 receptor occupancy is associated with an increased cardiovascular risk from NSAIDs. Conclusion: Cardiovascular safety of NSAIDs may depend on pharmacodynamic properties, specifically, the percentage of the occupied cyclooxygenase isoenzymes. More studies are needed to explore these relations and improve the prescription process.

Hormonal methods for emergency contraception.

The World Health Organization includes oral emergency contraception (EC) in the list of essential medicines. Ulipristal acetate (UPA) and levonorgestrel (LNG) are the recommended oral methods. UPA has superior efficacy and a comparable side effect profile compared with LNG. Both work by inhibiting or delaying ovulation, so that sperm present in the reproductive tract will have lost their fertilising ability by the time the oocyte is eventually released. Neither LNG nor UPA at the EC doses have significant effects on the endometrium and are unable to prevent implantation. Mifepristone can also be used for EC but its availability is limited to few countries. LNG is less effective in women with a body mass index over 26 kg/m2 or weight over 70 kg. Hormonal contraception can be quickstarted immediately following LNG, or five days following UPA. LNG-releasing intrauterine devices and cyclo-oxygenase inhibitors are promising options for EC to be further studied.

Immune-mediated impairment of tonic immobility defensive behavior in an experimental model of colonic inflammation.

Ulcerative colitis has been associated with psychological distress and an aberrant immune response. The immunomodulatory role of systemic cytokines produced during experimental intestinal inflammation in tonic immobility (TI) defensive behavior remains unknown. The present study characterized the TI defensive behavior of guinea pigs subjected to colitis induction at the acute stage and after recovery from intestinal mucosa injury. Moreover, we investigated whether inflammatory mediators (tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-8, IL-10, and prostaglandins) act on the mesencephalic nucleus, periaqueductal gray matter (PAG). Colitis was induced in guinea pigs by intrarectal administration of acetic acid. The TI defensive behavior, histology, cytokine production, and expression of c-FOS, IBA-1, and cyclooxygenase (COX)-2 in PAG were evaluated. Colitis reduced the duration of TI episodes from the first day, persisting throughout the 7-day experimental period. Neuronal c-FOS immunoreactivity was augmented in both columns of the PAG (ventrolateral (vlPAG) and dorsal), but there were no changes in IBA-1 expression. Dexamethasone, infliximab, and parecoxib treatments increased the duration of TI episodes, suggesting a modulatory role of peripheral inflammatory mediators in this behavior. Immunoneutralization of TNF-α, IL-1ß, and IL-8 in the vlPAG reversed all effects produced by colitis. In contrast, IL-10 neutralization further reduced the duration of TI episodes. Our results reveal that peripherally produced inflammatory mediators during colitis may modulate neuronal functioning in mesencephalic structures such as vlPAG.

Cyclooxygenase 2 Inhibitors for Headache After Elective Cranial Neurosurgery: Results from a Systematic Review of Efficacy of Cyclooxygenase 2 Inhibitors for Headache After Acute Brain Injury.

Headache management after acute brain injury (ABI) is challenging. Although opioids are commonly used, selective cyclooxygenase 2 inhibitors (COXIBs) may be promising alternatives. However, concerns about cardiovascular effects and bleeding risk have limited their use. We aimed at summarizing available data on efficacy of COXIBs for headache management following ABI. A systematic review was conducted through MEDLINE and Embase for articles published through September 2023 (PROSPERO identifier: CRD42022320453). No language filters were applied to the initial searches. Interventional or observational studies and systematic reviews assessing efficacy of COXIBs for headache in adults with ABI were eligible. Article selection was performed by two independent reviewers using DistillerSR. Descriptive statistics were used for data analysis, and meta-analysis was unfeasible because of study heterogeneity. Of 3190 articles identified, 6 studies met inclusion criteria: 4 randomized controlled trials and 2 retrospective cohort studies, all conducted in elective cranial neurosurgical patients (total N = 738) between 2006 and 2022. Five studies used COXIBs in the intervention group only. Of the six studies, four found a reduction in overall pain scores in the intervention group, whereas one showed improvement only at 6 h postoperatively, and one did not find significant differences. Pain scores decreased between 4 and 15%, the largest shift being from moderate to mild severity. Three studies found an overall opioid use reduction throughout hospitalization in the intervention group, whereas one reported a reduction at 12 h postoperatively only. Opioid consumption decreased between 9 and 90%. Two studies found a decrease in hospital length of stay by ~ 1 day in the intervention group. The one study reporting postoperative hemorrhage found a statistically nonsignificant 3% reduction in the intervention group. COXIBs may serve as opioid-sparing adjunctive analgesics for headache control after elective cranial surgery. Limited or no literature exists for other forms of ABI, and additional safety data remain to be elucidated.

Effect of curcumin on formalin-induced muscle pain in male rats: role of local cyclooxygenase system.

Investigating the mechanisms responsible for pain processing of natural and synthetic chemical compounds is necessary to optimize pain management. Curcumin (Cur), the active ingredient of turmeric, exhibits potent analgesic and anti-inflammatory properties by employing multiple mechanisms at the local peripheral, spinal and supra-spinal levels. This study was aimed to investigate the effect of oral administration of Cur on muscle pain induced by intramuscular (IM) injection of formalin. To explore the possible local mechanisms, a cyclooxygenase (COX) inhibitor, diclofenac (Dic) and a COX product, prostaglandin E2 (PGE2), were applied. The IM injection of formalin (25.00 µL, 2.50%) into the gastrocnemius muscle induced two distinct phases of hind leg flinching. A short-lasting (10 min) hind leg lifting was observed following IM injection of PGE2 (2 µg kg-1, 25.00 µL). Oral administration of Cur (25.00 and 100 mg kg-1) and IM injection of 40.00 µg kg-1 Dic attenuated formalin and PGE2 induced nociceptive behaviors. Contra-lateral IM injection of Dic did not change muscle pain induced by ipsilateral IM injection of formalin and PGE2. The second phase of formalin induced flinching as well as PGE2 evoked lifting were more suppressed when 40.00 µg kg-1 Dic and 100 mg kg-1 Cur were used together. Locomotor activity was not changed by the above-mentioned treatments. It was concluded that the reducing effect of muscle pain of Cur might be related to the local inhibition of COX.

Emodin inhibits benzidine­enhanced survival and migration of upper urinary tract urothelial carcinoma cells by targeting the PKA/COX2 signaling pathway.

The carcinogenic effects of benzidine (BZ) on bladder cancer are well documented, but its potential for promoting upper urinary tract urothelial carcinoma (UTUC) remains unclear. The ability of emodin, a natural pharmaceutical compound, to prevent BZ­associated UTUC has not been previously explored. To the best of our knowledge, the present study is the first to reveal that BZ significantly enhanced the survival and migration of UTUC cell lines in vitro. Furthermore, in vivo experiments demonstrated that BZ promoted an increase in the size of subcutaneous tumors in nude mice. Further investigation revealed that BZ upregulated the expression of protein kinase A (PKA) and cyclooxygenase 2 (COX2), along with downstream matrix metalloproteinase 9 (MMP9) and vascular endothelial growth factor (VEGF), in UTUC cells. Moreover, BZ increased the levels of cyclic adenosine monophosphate (cAMP) and prostaglandin E2 (PGE2) in cell lysates. By contrast, emodin reduced the PKA and COX2 expression levels compared with the BZ­treated group. Similarly, the in vivo experiments demonstrated that emodin significantly inhibited tumor growth in BZ­pretreated nude mice, accompanied by reductions in the cAMP, PGE2, MMP9 and VEGF levels. These findings elucidated the role of BZ in promoting UTUC progression. Additionally, emodin has emerged as a novel inhibitor of BZ­induced UTUC development through PKA/COX2 inhibition, suggesting its potential as a natural therapeutic agent against BZ­associated UTUC.

Do NSAIDs affect bone healing rate, delay union, or cause non-union: an updated systematic review and meta-analysis.

Introduction: Nonsteroidal anti-inflammatory drugs (NSAIDs) may potentially delay or cause non-union of fractures by inhibiting prostaglandin synthesis. However, studies have shown conflicting results. This systematic review and meta-analysis aim to synthesize current evidence on the potential influence of NSAIDs on bone healing. Methods: We conducted a comprehensive search of PubMed, Embase, and Cochrane CENTRAL databases for studies published up to 25 July 2023. Specific keywords included "NSAID," "nonsteroidal anti-inflammatory drug," "cyclooxygenase-2 inhibitor," "bone healing," "non-union," "pseudoarthrosis," "delayed union," and "atrophic bone." Eligible studies included prospective, retrospective, and case-controlled studies assessing the correlation between NSAID use and bone healing outcomes. The leave-one-out approach was used to test the robustness of the meta-analysis results. Results: A total of 20 studies with 523,240 patients were included in the analysis. The mean patient age ranged from 6.7 to 77.0 years, with follow-up durations from 3 to 67 months. The meta-analysis revealed no significant difference in non-union or delayed union between NSAID users and non-users [pooled adjusted odds ratio (OR) = 1.11; 95% confidence interval (CI): 0.99-1.23]. Initial analysis identified a significant association between NSAID usage and an increased risk of reoperation, but this association became insignificant upon sensitivity analysis (crude OR = 1.42; 95% CI: 0.88-2.28). Discussion: NSAIDs may have a minimal impact on non-union or delayed union risks. However, caution is advised due to the limited number of studies and the absence of a specific focus on NSAID types and dosages. Further research is necessary to better understand the implications of NSAID use on bone healing.

Beta-adrenergic receptor stimulation, histamine receptor inhibition, and potassium channel opening contribute to the relaxant effects of crocetin on airway smooth muscle.

Objectives: In the present study, the relaxant effect of crocetin on tracheal smooth muscle cells (TSM) and its possible mechanisms were evaluated. Materials and Methods: The study was conducted on 54 male Wistar rats in 8 groups. TSM was contracted by methacholine (10 µM) and KCl (60 mM), and the relaxant effects of four cumulative concentrations of crocetin, petal extract of saffron, and theophylline were examined on non-incubated and TSM incubated with propranolol, chlorpheniramine, diltiazem, atropine, glibenclamide, and indomethacin were investigated. Results: In non-incubated TSM contracted by methacholine or KCl, crocetin and theophylline showed concentration-dependent relaxant effects (all, P<0.001). However, various concentrations of crocetin showed significantly lower relaxant effects compared to those of theophylline (all, P<0.001). In the methacholine-induced contraction of TSM, the relaxation effect of the last concentration of crocetin in the TSM incubated with propranolol was lower than in non-incubated TSM (P<0.05). In the incubated TSM with chlorpheniramine, the relaxant effects of the two last concentrations of crocetin were significantly lower than in the non-incubated tissues contracted by KCl (P<0.05 and P<0.0). The levels of EC50 crocetin in the incubated TSM with glibenclamide, chlorpheniramine, and indomethacin were markedly lower than in non-incubated (all, P<0.05). Conclusion: The results showed potent relaxation effects of crocetin on TSM and were suggested to be through stimulation of ß-adrenergic receptors, inhibition of histamine (H1) receptors, and potassium channel opening mechanisms.

Expression of vascular endothelial growth factor receptor-2, epidermal growth factor receptor, cyclooxygenase-2, survivin, E-cadherin and Ki-67 in canine nasal carcinomas and sarcomas - a pilot study.

Background: Malignant (intra-) nasal tumors (NTs) are the most common cause of chronic nasal discharge in dogs. Besides radiation therapy, palliative therapy is necessary in some dogs. Therefore, studies on receptor expression have supported the utility of tyrosine kinase inhibitors (TKI) in dogs with nasal carcinomas. However, studies on receptor expression in nasal sarcomas are lacking. Materials and methods: This study evaluated the expression of vascular endothelial growth factor receptor-2 (VEGFR-2), epidermal growth factor receptor (EGFR), cyclooxigenase-2 (COX-2), Ki-67, survivin and E-cadherin in nasal carcinomas and sarcomas and compared it with tumor (T) categories based on computed tomography (CT). Results: In 26 dogs with NTs, cross sectional imaging and upper airway endoscopy with guided biopsy collection were performed, followed by histopathological examination of NTs, revealing 19 epithelial and 7 mesenchymal tumors. While EGFR and E-cadherin were only expressed by carcinomas, the following markers were expressed by both carcinomas and sarcomas without significant differences between tumor types and T-categories: VEGFR-2 (carcinomas and sarcomas 100%), COX-2 (carcinomas 63%, sarcomas 57%), survivin (carcinomas 100%, sarcomas 86%) and Ki-67 (median expression of 28.5% in carcinomas and 17.3% in sarcomas). Conclusion: Based on similarities in marker expression between canine carcinomas and sarcomas, clinical studies should further elucidate the use of TKI or COX-2 inhibitors as additional therapy in dogs with nasal sarcomas.

The Phytochemical, Quercetin, Attenuates Nociceptive and Pathological Pain: Neurophysiological Mechanisms and Therapeutic Potential.

Although phytochemicals are plant-derived toxins that are primarily produced as a form of defense against insects or microbes, several lines of study have demonstrated that the phytochemical, quercetin, has several beneficial biological actions for human health, including antioxidant and inflammatory effects without side effects. Quercetin is a flavonoid that is widely found in fruits and vegetables. Since recent studies have demonstrated that quercetin can modulate neuronal excitability in the nervous system, including nociceptive sensory transmission via mechanoreceptors and voltage-gated ion channels, and inhibit the cyclooxygenase-2-cascade, it is possible that quercetin could be a complementary alternative medicine candidate; specifically, a therapeutic agent against nociceptive and pathological pain. The focus of this review is to elucidate the neurophysiological mechanisms underlying the modulatory effects of quercetin on nociceptive neuronal activity under nociceptive and pathological conditions, without inducing side effects. Based on the results of our previous research on trigeminal pain, we have confirmed in vivo that the phytochemical, quercetin, demonstrates (i) a local anesthetic effect on nociceptive pain, (ii) a local anesthetic effect on pain related to acute inflammation, and (iii) an anti-inflammatory effect on chronic pain. In addition, we discuss the contribution of quercetin to the relief of nociceptive and inflammatory pain and its potential clinical application.

Short-Term Celecoxib Promotes Bone Formation without Compromising Cefazolin Efficacy in an Early Orthopaedic Device-Related Infection: Evidence from a Rat Model.

Non-steroidal anti-inflammatory drugs (NSAIDs) are crucial components of multimodal analgesia for musculoskeletal injuries, targeting cyclooxygenase (COX) enzymes (COX-1 and/or COX-2 isoenzymes). Concerns exist regarding their potential interference with bone healing and orthopaedic device-related infections (ODRI), where data are limited. This study aimed to investigate whether the COX-selectivity of NSAIDs interfered with antibiotic efficacy and bone changes in the setting of an ODRI. In vitro testing demonstrated that combining celecoxib (a COX-2 inhibitor) with cefazolin significantly enhanced antibacterial efficacy compared to cefazolin alone (p < 0.0001). In vivo experiments were performed using Staphylococcus epidermidis in the rat proximal tibia of an ODRI model. Long and short durations of celecoxib treatment in combination with antibiotics were compared to a control group receiving an antibiotic only. The long celecoxib treatment group showed impaired infection clearance, while the short celecoxib treatment showed increased bone formation (day 6, p < 0.0001), lower bone resorption (day 6, p < 0.0001), and lower osteolysis (day 6, BV/TV: p < 0.0001; BIC: p = 0.0005) compared to the control group, without impairing antibiotic efficacy (p > 0.9999). Given the use of NSAIDs as part of multimodal analgesia, and considering these findings, short-term use of COX-2 selective NSAIDs like celecoxib not only aids pain management but also promotes favorable bone changes during ODRI.

Selective COX-2 Inhibitors as Neuroprotective Agents in Traumatic Brain Injury.

Traumatic brain injury (TBI) is a significant contributor to mortality and morbidity in people, both young and old. There are currently no approved therapeutic interventions for TBI. Following TBI, cyclooxygenase (COX) enzymes generate prostaglandins and reactive oxygen species that perpetuate inflammation, with COX-1 and COX-2 isoforms providing differing responses. Selective COX-2 inhibitors have shown potential as neuroprotective agents. Results from animal models of TBI suggest potential treatment through the alleviation of secondary injury mechanisms involving neuroinflammation and neuronal cell death. Additionally, early clinical trials have shown that the use of celecoxib improves patient mortality and outcomes. This review aims to summarize the therapeutic effects of COX-2 inhibitors observed in TBI animal models, highlighting pertinent studies elucidating molecular pathways and expounding upon their mechanistic actions. We then investigated the current state of evidence for the utilization of COX-2 inhibitors for TBI patients.

Investigation of the Anti-Inflammatory Properties of Bioactive Compounds from Olea europaea: In Silico Evaluation of Cyclooxygenase Enzyme Inhibition and Pharmacokinetic Profiling.

In a landmark study, oleocanthal (OLC), a major phenolic in extra virgin olive oil (EVOO), was found to possess anti-inflammatory activity similar to ibuprofen, involving inhibition of cyclooxygenase (COX) enzymes. EVOO is a rich source of bioactive compounds including fatty acids and phenolics; however, the biological activities of only a small subset of compounds associated with Olea europaea have been explored. Here, the OliveNetTM library (consisting of over 600 compounds) was utilized to investigate olive-derived compounds as potential modulators of the arachidonic acid pathway. Our first aim was to perform enzymatic assays to evaluate the inhibitory activity of a selection of phenolic compounds and fatty acids against COX isoforms (COX-1 and COX-2) and 15-lipoxygenase (15-LOX). Olive compounds were found to inhibit COX isoforms, with minimal activity against 15-LOX. Subsequent molecular docking indicated that the olive compounds possess strong binding affinities for the active site of COX isoforms, and molecular dynamics (MD) simulations confirmed the stability of binding. Moreover, olive compounds were predicted to have favorable pharmacokinetic properties, including a readiness to cross biological membranes as highlighted by steered MD simulations and umbrella sampling. Importantly, olive compounds including OLC were identified as non-inhibitors of the human ether-à-go-go-related gene (hERG) channel based on patch clamp assays. Overall, this study extends our understanding of the bioactivity of Olea-europaea-derived compounds, many of which are now known to be, at least in part, accountable for the beneficial health effects of the Mediterranean diet.