Inhibition Of Cyclooxygenase Enzymes Research Articles

Aspirin as a chemopreventive agent for cutaneous melanoma: a literature review.

Rising melanoma rates have spurred interest in preventive strategies. Nonsteroidal anti-inflammatory drugs (NSAIDs), particularly aspirin, show potential in reducing cancer risks. NSAIDs act on cyclooxygenase (COX) enzymes, impacting COX-2 associated with inflammation and cancer progression.This paper explores aspirin's role in cutaneous melanoma prevention, elucidating its mechanisms and acknowledging varying literature outcomes. Rather than providing conclusive recommendations, the review emphasizes the influence of individual factors, contributing to the ongoing dialogue on aspirin's complexities in melanoma prevention. A PubMed search using "Aspirin" AND "Cutaneous melanoma" yielded relevant English-language, peer-reviewed studies. Selection criteria focused exclusively on skin cancers, specifically cutaneous melanoma. Exclusions included studies covering various cancers, some non-dermatologic, and those not evaluating aspirin use independently but in conjunction with NSAIDs. The potential chemopreventive effects of aspirin and NSAIDs against melanoma have gained attention due to their association with a reduced risk of various cancers including gastric, colorectal, and breast. By inhibiting COX enzymes and the NF-κB pathway, these agents theoretically slow malignant cell activities, presenting a prospect for cancer prevention. Aspirin exhibits noteworthy effects, depleting growth-stimulating hormones, generating reactive oxygen species harmful to cancerous cells, and inhibiting COX-2 linked to cancer progression. Limited literature suggests survival benefits with aspirin use in stage II and III melanoma, possibly due to slowing disease progression, evident in smaller Breslow depths. Gender-specific responses to aspirin are notable, with some studies reporting a stronger chemopreventive correlation in females. It's crucial to note that geographic disparities, demographic cohorts, and individual-specific factors are confounding variables that may contribute to conflicting findings regarding aspirin's impact on melanoma. The association between aspirin use and melanoma risk is complex, with conflicting findings across diverse populations. Although it appears that more studies suggest a protective role for aspirin rather than not, evidence lacks consistency. Factors such as gender, geography, race, sun exposure, and health conditions play a role in shaping these varied outcomes, necessitating large-scale, prospective studies research and standardized parameters for more conclusive insights that may help guide tailored clinical strategies for melanoma prevention.

Exposure to Benzo(a)pyrene Enhances Acetaminophen-Induced Liver Injury in Mice at Non-Hepatotoxic Doses

Acetaminophen (APAP) is a widely used analgesic, especially for children. Its primary mechanism involves inhibiting cyclooxygenase enzymes and activating the endocannabinoid and TRPV1 systems. Though its toxicity is low, it can harm the liver in a dose-dependent manner. Low APAP doses can also increase pollutant-induced liver damage. Little is known about interactions between APAP and benzo[a]pyrene (B[a]P). This study aimed to assess if co-exposure to non-hepatotoxic doses of B[a]P and APAP causes liver injury in mice, exploring the underlying mechanisms. Female ICR mice received 50 mg/kg B[a]P or a vehicle for three days, followed by 200 mg/kg APAP or a vehicle. Liver injury was assessed through histopathological examination, serum transaminase activity, and gene expression analysis. In the B[a]P/APAP group, several histology changes were observed, including ballooning injury, steatosis, necrosis, inflammation, and apoptosis. Transaminase levels correlated with histopathological scores, and there was an increase in hepatic cytochrome P450 family 1 subfamily a member 1 (Cyp1a1) mRNA levels and a decrease in aryl hydrocarbon receptor (Ahr), cytochrome P450 family 2 subfamily e polypeptide 1 (Cyp2e1), superoxide dismutase 1 (Sod1), peroxisome proliferator activated receptor gamma (Ppar-γ), and caspase 3 (Casp3). This suggests that prior exposure to B[a]P makes mice more susceptible to APAP-induced liver injury, involving changes in gene expression related to metabolism, redox balance, and cell proliferation. Therefore, using therapeutic APAP doses after exposure to B[a]P could lead to liver injury.

Pyrazoles have a multifaceted anti-inflammatory effect targeting prostaglandin E2, cyclooxygenases and leukocytes’ oxidative burst

Elevated levels of prostaglandin E2 have been implicated in the pathophysiology of various diseases. Anti-inflammatory drugs that act through the inhibition of cyclooxygenase enzymatic activity, thereby leading to the suppression of prostaglandin E2, are often associated with several side effects due to their non-specific inhibition of cyclooxygenase enzymes. Consequently, the targeted suppression of prostaglandin E2 production with innovative molecules and/or mechanisms emerges as a compelling therapeutic strategy for the treatment of inflammatory-related diseases. Therefore, in this study, a systematic analysis of 28 pyrazole derivatives was conducted to explore their potential mechanisms for reducing prostaglandin E2 levels. In this context, the evaluation of these derivatives extended to examining their capacity to reduce prostaglandin E2in vitro in human whole blood, inhibit cyclooxygenase-1 and cyclooxygenase-2 enzymes, modulate cyclooxygenase-2 expression, and suppress oxidative burst in human leukocytes. The results enabled the establishment of significant structure-activity relationships, elucidating key determinants for their activities. In particular, the 4-styryl group on the pyrazole moiety and the presence of chloro substitutions were identified as key determinants. Pyrazole 8 demonstrated the capacity to reduce prostaglandin E2 levels by downregulating cyclooxygenase-2 expression, and pyrazole-1,2,3-triazole 18 emerged as a dual-acting agent, inhibiting human leukocytes' oxidative burst and cyclooxygenase-2 activity. Furthermore, pyrazole 26 demonstrated effective reduction of prostaglandin E2 levels through selective cyclooxygenase-1 inhibition. These results underscore the multifaceted anti-inflammatory potential of pyrazoles, providing new insights into the substitutions and structural frameworks that are beneficial for the studied activity.

Synthesis and anti-HCV activity of novel 5-arylmethylene-1,3-thiazolidin-4-one derivatives via suppression of NS5B polymerase and COX-2

Hepatitis C (HCV) is a viral infection that leads to forms of acute and chronic liver disease, including cirrhosis (scarring of the liver) and liver cancer. The World Health Organization (WHO) estimated in 2019 that approximately 290,000 people died from hepatitis C (mostly from cirrhosis and hepatocellular carcinoma). Direct-acting antiviral drugs (DAAs) can cure more than 95% of individuals with hepatitis C infection, while research on the discovery of new antiviral agents is still ongoing. The Hepatitis C virus (HCV) can cause various biochemical changes in liver cells, and some of these changes are associated with the COX-2 enzyme. The identification of its role in promoting growth in liver cells as well as its involvement in various cancer types, including hepatocellular carcinoma, has made COX-2 an important target in the development of new agents effective against HCV. In this study, thirty-six new 5-arylmethylene-2-imino-1,3-thiazolidin-4-one derivatives (5a-s, 6a-s) were synthesized through Knoevenagel condensation of 2-[(4-substitutedpyridin-2-yl)imino]-1,3-thiazolidin-4-one derivatives with various aldehydes. Structures of the synthesized compounds were elucidated by the use of spectral and chromatographic techniques, besides elemental analyses. Four compounds were selected for further studies as they were found to suppress the NS5B protein with anti-HCV activity using the Western Blotting method. The selected compounds 5o, 6m, 6r, and 6s inhibited HCV with EC50 values of 8.0 ± 0.2 µM, 13.9 ± 0.45, 9.2 ± 0.2 µM, and 12.1 ± 0.1 µM, respectively. It was determined that these compounds reduced HCV-induced COX-2 promoter activity in Ava5 cells compared to Huh7 cells. The antiviral effects of the compounds were also investigated on DENV, closely related to HCV due to sharing certain biological, structural, and mechanical properties throughout their life cycles. However, no significant effect was observed in the preliminary screening study, indicating the compounds' specificity for HCV. Considering the relationship between HCV, DENV, and COX-2, the compounds' COX-1 and COX-2 enzyme inhibition potentials were investigated both in vitro and in silico. Compounds 6d, 6e, 6f, and 6m, which exhibited high selective COX-2 inhibition, were discussed for their interactions with the active site. Our study revealed that our target compounds suppressed COX-2 both at the protein level and through enzyme inhibition, thus providing promising findings for the discovery of new anti-HCV effective COX-2 inhibitors.

Comparative Assessment of Lignan Profiling and Biological Activities of Schisandra henryi Leaf and In Vitro PlantForm Bioreactor-Grown Culture Extracts.

This research's scope encompassed biotechnological, phytochemical, and biological studies of Schisandra henryi, including investigations into its in vitro microshoot culture grown in PlantForm bioreactors (temporary immersion systems, TISs), as well as extracts from leaves of the parent plant, focusing on anti-inflammatory, antioxidant, anticancer, and antimicrobial activities. The phytochemical analysis included the isolation and quantification of 17 compounds from dibenzocyclooctadiene, aryltetralin lignans, and neolignans using centrifugal partition chromatography (CPC), HPLC-DAD, and UHPLC-MS/MS tandem mass spectrometry with triple quadrupole mass filter methods. Higher contents of compounds were found in microshoots extracts (max. 543.99 mg/100 g DW). The major compound was schisantherin B both in the extracts from microshoots and the leaves (390.16 and 361.24 mg/100 g DW, respectively). The results of the anti-inflammatory activity in terms of the inhibition of COX-1, COX-2, sPLA2, and LOX-15 enzymes indicated that PlantForm microshoot extracts showed strong activity against COX-1 and COX-2 (for 177 mg/mL the inhibition percentage was 76% and 66%, respectively). The antioxidant potential assessed using FRAP, CUPRAC, and DPPH assays showed that extracts from microshoot cultures had 5.6, 3.8, and 3.3 times higher power compared to extracts from the leaves of the parent plant, respectively. The total polyphenol content (TPC) was 4.1 times higher in extracts from the in vitro culture compared to the leaves. The antiproliferative activity against T-cell lymphoblast line Jurkat, breast adenocarcinoma cultures (MCF-7), colon adenocarcinoma (HT-29), and cervical adenocarcinoma (HeLa), showed that both extracts have considerable effects on the tested cell lines. The antimicrobial activity tested against strains of Gram-positive and Gram-negative bacteria and fungi showed the highest activity towards H. pylori (MIC and MBC 0.625 mg/mL).

Identifying Risk Factors for Cardiovascular Events Among Active-Duty Service Members and Veterans Prescribed Nonsteroidal Anti-Inflammatory Drugs (NSAIDs).

Oral NSAIDs are widely used analgesic medications for the treatment of musculoskeletal and inflammatory conditions. NSAIDs are associated with adverse effects that arise from COX enzyme inhibition including cardiovascular events. The combined role of patient and prescription factors associated with NSAID use on cardiovascular risk is not well characterized. The purpose of this study is to identify the risk factors with cardiovascular events among NSAID users. This study is a retrospective, nested case-control study, within the DAVINCI database, among active-duty service members and veterans with at least one NSAID pharmacy claim between fiscal year (FY) 2015-FY2020. Inclusion criteria individuals ≥18 years of age received a prescription NSAID for ≥7-day supply and a duration ≥1 month overall. Cases experienced nonfatal myocardial infarction, nonfatal stroke, or new onset heart failure. Ten controls were selected per case. Risk factors were identified through logistic regression modeling. The risk factors with strongest association to the primary outcome included age starting at 45 up to 75 and older, the first 90 days of NSAID exposure, cerebrovascular disease, cardiomyopathy, and history of myocardial infarction. Cox-selectivity and dose did not appear to be clinically significant in their association with cardiovascular events. The results of this study indicate that age, initial NSAID exposure, and comorbidities are more predictive than NSAID-specific factors such as COX-selectivity and dose. The results provide the framework for development of a risk score to improve prediction of NSAID-associated cardiovascular events.

Anti-inflammatory ability of licorice (Glycyrrhiza glabra) root extract in cyclooxygenase-2 enzyme inhibition: In silico study

Background: Inflammation represents the body's natural response to injury, which can be induced by chemical, physical, or biological agents. Current approaches to managing inflammatory conditions involve addressing the primary etiological factors and administering anti-inflammatory medications like Nonsteroid Anti Inflammatory Drugs (NSAIDs) in inhibiting cyclooxygenase 2 (COX-2). However, data from 2021 reveals that 78.8% of patients experience gastritis as a side effect of such treatment. Licorice root extract (LRE)-an ayurvedic plants emerges as a promising alternative due to its potent anti-inflammatory properties attributed to the presence of glycyrrhizin, constituting between 2% to 25% of its dry weight. Objectives: To find out and determine the molecular inhibition of compound in LRE against COX-2 enzyme. Method: The process involves isolating the active constituents of LRE using pubchem and BioVia application, isolation active site of COX-2 by exploring RCSB PDB and isolate it using PyMol and engaging in molecular docking simulations using PyRx. Results and discussions: Cyclooxygenase-2 (COX-2) emerges as a pivotal enzymatic orchestrator intricately woven into the fabric of the inflammatory cascade. Licorice root extract stands at the forefront of prospective candidates in the realm of anti-inflammatory drug development, buoyed by its remarkable anti-inflammatory attributes. Regarding to ∆Gbind value, molecular docking tests show LRE compounds inhibit COX-2 better than arachidonic acid and mefenamic acid. Six LRE compounds outperform reference compounds, indicating potential anti-inflammatory capabilities. Other compounds show anti-inflammatory activity, and RMSD values affirm the accuracy of in silico predictions. Conclusion: LRE had potential as oral topical anti-inflammatory drugs through COX-2 inhibition with the best anti-inflammation ability is 18β‐glycyrrhetic acid.

Chromone-based small molecules for multistep shutdown of arachidonate pathway: Simultaneous inhibition of COX-2, 15-LOX and mPGES-1 enzymes

As a new approach to the management of inflammatory disorders, a series of chromone-based derivatives containing a (carbamate)hydrazone moiety was designed and synthesized. The compounds were assessed for their ability to inhibit COX-1/2, 15-LOX, and mPGES-1, as a combination that should effectively impede the arachidonate pathway. Results revealed that the benzylcarbazates (2a-c) demonstrated two-digit nanomolar COX-2 inhibitory activities with reasonable selectivity indices. They also showed appreciable 15-LOX inhibition, in comparison to quercetin. Further testing of these compounds for mPGES-1 inhibition displayed promising activities. Intriguingly, compounds 2a-c were capable of suppressing edema in the formalin-induced rat paw edema assay. They exhibited an acceptable gastrointestinal safety profile regarding ulcerogenic liabilities in gross and histopathological examinations. Additionally, upon treatment with the test compounds, the expression of the anti-inflammatory cytokine IL-10 was elevated, whereas that of TNF-α, iNOS, IL-1β, and COX-2 were downregulated in LPS-challenged RAW264.7 macrophages. Docking experiments into the three enzymes showed interesting binding profiles and affinities, further substantiating their biological activities. Their in silico physicochemical and pharmacokinetic parameters were advantageous.

Development of safe and antioxidant COX-2 inhibitors; Synthesis, molecular docking analysis and biological evaluation of novel pyrrolizine 5-carboxamides

In the current study, a series of new pyrrolizine-5-carboxamide derivatives (5–8, 9a-d, 10a-d, 11a,b and 12a,b) were developed, synthesized and evaluated in terms of in vitro COX-2 enzyme inhibition. The in vivo anti-inflammatory evaluation was conducted on the most selective compounds (9a,b,d, 10b,c and 11a,b). For the most active five compounds (9a, 10b,c and 11a,b), ulcerogenic liability, histopathological examinations, physicochemical properties study and antioxidant activity were investigated. Also, nitric oxide donor activity was evaluated for compounds (6, 7, 10a-d and 12a,b), while, compounds (10c,d and 12a,b) showed a high significant result relative to the normal control. According to the findings of this study, 2,3-dihydro-1H-pyrrolizine-5-carboxamide (9a) demonstrated high antioxidant (highest beta-carotene concentration (10.825 µg/ml)) and anti-inflammatory activity (EIP = 63.6 %) with lower ulcerogenicity (ulcer index 13.67), presenting it as a promising candidate for treating inflammatory diseases which are complicated by oxidative tissue damage. Furthermore, MOE software tools docking software was used to carry out the in silico studies. Docking study for the most active compounds showed that all compounds made three to four H-bond interactions in COX-2 active site adopting excellent docking scores.

Synthesis and anti-inflammatory activity of novel firocoxib analogues with balanced COX inhibition.

The adverse effects caused by nonselective and selective cyclooxygenase-2 (COX-2) inhibitors remain a challenge for current anti-inflammatory medications. A balanced inhibition of COX-1/-2 represents a promising strategy for the development of novel COX-2 inhibitors. In this study, we present the design and synthesis of a novel series of firocoxib analogues incorporating an amide bond to facilitate essential hydrogen bonding with amino residues in COX-2. The synthesized analogs were evaluated for their inhibitory activity against both COX-1 and COX-2 enzymes. Among them, compound 9d demonstrated potent and balanced inhibition. Inhibition of COX enzymes by 9d in lipopolysaccharide (LPS)-stimulated murine RAW264.7 macrophages resulted in the suppression of the NF-κB signaling pathway to reduced expression of pro-inflammatory factors such as inducible nitric oxide synthase (iNOS), COX-2, nitric oxide (NO), and reactive oxygen species (ROS). The remarkable invitro anti-inflammatory activity exhibited by 9d positions it as a promising candidate for further development as a novel lead compound for inflammation treatment.

Synthesis, docking and biological evaluation of purine-5-N-isosteresas anti-inflammatory agents.

An operationally simple one-pot three-component and convenient synthesis method for a series of diverse purine analogues of 5-amino-7-(substituted)-N-(4-sulfamoylphenyl)-4,7-dihydro-[1,2,4]-triazolo[1,5-a][1,3,5]triazine-2-carboxamide derivatives generated in situ via the reaction of 2-hydrazinyl-N-(4-sulfamoylphenyl)-2-thioxoacetamide, cyanoguanidine and a variety of aldehydes was achieved under green conditions. This experiment was conducted to evaluate the anti-inflammatory effect of the newly synthesized compounds using indomethacin as a reference medication; all compounds were tested for in vitro anti-inflammatory activity using the inhibition of albumin denaturation, RBC hemolysis technique and COX inhibition assay. The results showed that all evaluated compounds exhibited significant in vitro anti-inflammatory efficacy leading to excellently effective RBC membrane stabilization, inhibition of protein denaturation, and inhibition of COX enzymes when compared to those of indomethacin. At concentrations of 50, 100, 200, and 300 μg ml-1, these compounds decreased COX-1 and COX-2 activities more than indomethacin and have IC50 values in the range of 40.04-87.29 μg ml-1 for COX-1 and 27.76-42.3 μg ml-1 for COX-2 while indomethacin showed IC50 = 91.57 for COX-1 and 42.66 μg ml-1 for COX-2. The anti-inflammatory findings show the need for more investigation to define the properties underlying the evaluated compounds' anti-inflammatory abilities. The enzyme cyclooxygenase-2 (COX 2) (PDB ID: 5IKT) was docked with ten synthetic substances. With docking scores (S) of -8.82, -7.82, and -7.76 kcal mol-1, 7-furan triazolo-triazine (4), 7-(2-hydroxy phenyl) triazolo-triazine (11), and 7-(4-dimethylamino phenyl) triazolo-triazine (12) had the greatest binding affinities, respectively. Therefore, these substances have COX-2 (PDB ID: 5IKT) inhibitory capabilities and hence may be investigated for COX 2 targeting development. Furthermore, both the top-ranked compounds (4 and 11) and the standard indomethacin were subjected to DFT analysis. The HOMO - LUMO energy difference (ΔE) of the mentioned compounds was found to be less than that of indomethacin.

Molecular docking analysis of major active compounds of pomegranate peel extract (Punica granatum L.) in inhibiting cyclooxygenase enzyme

Background: Inflammation is the body's physiological response to an injury. Injury that affected the body can be a chemical agent, physical, or biological agent. Nowadays the inflammatory condition treated by eliminating the main etiological factor then prescribing anti-inflammatory drugs such as NSAIDs, but according the data in 2021 shown that 78,8% patients has gastritis side effect. Pomegranate peel extract (PPE) has good anti-inflammatory ability because it containing the highest concentration of flavonoid. Objectives: To predict the molecular inhibition of major active compounds (epigallocatachin gallate, ferulic acid, chlorogenic acid, gallic acid, caffeic acid, cianidanol, epicatechin, and punicalagin) in PPE against cyclooxygenase enzyme (COX-1 & COX-2) using in silico study. Method: Preparation of the active compounds of PPE, prediction of their activity, ADMET predicting test, physicochemical test, and molecular docking simulation. Results and discussions: In silico test showed that all common active compound of PPE that have potential as anti-inflammatory drugs. All of MAC PPE had value of Pa > 0.5. ADMET prediction showed that all common active compounds can distribute systemically because had score of log mucosal permeability < 2.5. All of common active compound in PPE had negative prediction not to toxic or triggering dermatitis contact against oral mucosa through ADMET prediction. The result of molecular docking of chlorogenic acid and punicalagin against protein of COX-2 showed ∆Gbind value more than mefenamic acid and arachidonic acid against COX-1 and COX-2 in range of -3,0 to -9,1 kcal/mol which the most effective as an anti-inflammatory is punicalagin (-4,0 & -9,1 kcal/mol). Conclusion: PPE had potential as anti-inflammatory drugs through COX-1 & COX-2 inhibition with the best anti-inflammation ability is ferrulic acid and punicalagin.

Prodrug Approach: NSAID Conjugates of Platinum Compounds as Anti-Cancer Agents

Prodrug based synthetic approach is a very promising area of research to enhance the pharmaco–kinetic and pharmaco-dynamic properties of the drugs with the remarkable reduction of the side effects. Prodrug can be used for drugs which are having poor solubility, poor transport properties, production of chronic side effects thus this approach provides a powerful tool for novel drug conjugate with improved therapeutic value. Platinum based anti-neoplastic agents are widely used in chemotherapeutic regimen but the side effects like hepatotoxicity, ototoxicity, cardiotoxicity, nausea and vomiting, diarrhea, mucositis, stomatitis, pain, alopecia, anorexia, cachexia, cytopenias and asthenia were reported. So the development of prodrugs by using platinum compounds and Non-steroidal anti-inflammatory drugs showed better therapeutic value with the reduction of side effects. Non-steroidal anti-inflammatory drugs are broad class of drugs showed Analgesic, Anti–inflammatory and Anti-pyretic activities based on the mechanism of cyclooxygenase (cox-1 and cox-2) enzyme inhibition and formation of prostaglandins. Also Non-steroidal anti-inflammatory drugs have different targets to elicit various pharmacological actions and are beneficial for many other diseases. The different targets are nuclear factor kappa B(NF-Κb), Peroxisome proliferator-activated receptors(PPAR), Mammalian target of rapamycin(mTOR), Autophagy, Cytochrome c, NSAID activated gene (NAG-1), Angiogenesis, Resolvins, Protectins, Maresins. This review focused on the development of platinum prodrugs by conjugating with different NSAIDs and the therapeutic applications of the developed novel molecules including dual action and triple action prodrugs. This review discussed the different aspects of prodrug based approach, Detail mechanism and other molecular targets of NSAIDs and the development of the platinum compounds –NSAID prodrugs.

ANALGESIC POWER OF THE INSOLUBLE FRACTION N-HEXANE OF MELINJO LEAVES (Gnetum gnemon L.) IN SWISS MICE (Mus musculus)

Melinjo (Gnetum gnemon L.) contains various secondary metabolites, including alkaloids, flavonoids, saponins, and tannins. Flavonoids function as analgesics and inhibit cyclooxygenase enzymes, which reduce prostaglandin production and pain. This study aimed to determine the analgesic power of the n-hexane-insoluble fraction of melinjo leaves (Gnetum gnemon L.) as an effective analgesic in male white mice (Mus musculus) and to determine the most effective analgesic dose. This research was conducted using test animals of 25 male white mice (Mus musculus) divided into 5 groups, each consisting of 5 mice. The negative control group (Na-CMC) was 0.5%, the positive control group received a mefenamic acid dose of 65 kg/BW, and the insoluble fraction hexane group (ifh) received doses of 50 mg/kg BW, 100 mg/kg BW, and 200 mg/kg BW. The chemical stimulus was administered at a dose of 400 mg/kg body weight acetic acid. The number of wriggles in male white mice (Mus musculus) was measured every 10 minutes for 60 minutes. The results of the study showed a significant difference between the negative control (Na-CMC 0.5%) and various doses of insoluble fraction hexane groups, while the positive control (mefenamic acid 65 mg/kg BB) showed no difference with ifh doses of 100 mg/kg BB and 200 mg/kg BB ...

Design and Evaluation of Synthesized Pyrrole Derivatives as Dual COX-1 and COX-2 Inhibitors Using FB-QSAR Approach.

This study delves into the intricate dynamics of the inflammatory response, unraveling the pivotal role played by cyclooxygenase (COX) enzymes, particularly COX-1 and COX-2 subtypes. Motivated by the pursuit of advancing scientific knowledge, our contribution to this field is marked by the design and synthesis of novel pyrrole derivatives. Crafted as potential inhibitors of COX-1 and COX-2 enzymes, our goal was to unearth molecules with heightened efficacy in modulating enzyme activity. A meticulous exploration of a synthesis library, housing around 3000 compounds, expedited the identification of potent candidates. Employing advanced docking studies and field-based Quantitative Structure-Activity Relationship (FB-QSAR) analyses enriched our understanding of the complex interactions between synthesized compounds and COX enzymes. Guided by FB-QSAR insights, our synthesis path led to the identification of compounds 4g, 4h, 4l, and 4k as potent COX-2 inhibitors, surpassing COX-1 efficacy. Conversely, compounds 5b and 5e exhibited heightened inhibitory activity against COX-1 relative to COX-2. The utilization of pyrrole derivatives as COX enzyme inhibitors holds promise for groundbreaking advancements in the domain of anti-inflammatory therapeutics, presenting avenues for innovative pharmaceutical exploration.

Role of K+ and Ca2+ Channels in the Vasodilator Effects of Plectranthus barbatus (Brazilian Boldo) in Hypertensive Rats.

Plectranthus barbatus, popularly known as Brazilian boldo, is used in Brazilian folk medicine to treat cardiovascular disorders including hypertension. This study investigated the chemical profile by UFLC-DAD-MS and the relaxant effect by using an isolated organ bath of the hydroethanolic extract of P. barbatus (HEPB) leaves on the aorta of spontaneously hypertensive rats (SHR). A total of nineteen compounds were annotated from HEPB, and the main metabolite classes found were flavonoids, diterpenoids, cinnamic acid derivatives, and organic acids. The HEPB promoted an endothelium-dependent vasodilator effect (~100%; EC50 ~347.10 μg/mL). Incubation of L-NAME (a nonselective nitric oxide synthase inhibitor; EC50 ~417.20 μg/mL), ODQ (a selective inhibitor of the soluble guanylate cyclase enzyme; EC50 ~426.00 μg/mL), propranolol (a nonselective α-adrenergic receptor antagonist; EC50 ~448.90 μg/mL), or indomethacin (a nonselective cyclooxygenase enzyme inhibitor; EC50 ~398.70 μg/mL) could not significantly affect the relaxation evoked by HEPB. However, in the presence of atropine (a nonselective muscarinic receptor antagonist), there was a slight reduction in its vasorelaxant effect (EC50 ~476.40 μg/mL). The addition of tetraethylammonium (a blocker of Ca2+-activated K+ channels; EC50 ~611.60 μg/mL) or 4-aminopyridine (a voltage-dependent K+ channel blocker; EC50 ~380.50 μg/mL) significantly reduced the relaxation effect of the extract without the interference of glibenclamide (an ATP-sensitive K+ channel blocker; EC50 ~344.60 μg/mL) or barium chloride (an influx rectifying K+ channel blocker; EC50 ~360.80 μg/mL). The extract inhibited the contractile response against phenylephrine, CaCl2, KCl, or caffeine, similar to the results obtained with nifedipine (voltage-dependent calcium channel blocker). Together, the HEPB showed a vasorelaxant effect on the thoracic aorta of SHR, exclusively dependent on the endothelium with the participation of muscarinic receptors and K+ and Ca2+ channels.

Comprehensive phytochemical characterization of Persea americana Mill. fruit via UPLC/HR-ESI–MS/MS and anti-arthritic evaluation using adjuvant-induced arthritis model

Persea americana Mill. (avocado fruit) has many health benefits when added to our diet due to various pharmacological activities, such as preventing bone loss and inflammation, modulating immune response and acting as an antioxidant. In the current study, the total ethanol extract (TEE) of the fruit was investigated for in vitro antioxidant and anti-inflammatory activity via DPPH and cyclooxygenase enzyme inhibition. Biological evaluation of the antiarthritic effect of the fruit extract was further investigated in vivo using Complete Freund’s Adjuvant (CFA) arthritis model, where the average percentages of body weight change, inhibition of paw edema, basal paw diameter/weight and spleen index were estimated for all animal groups. Inflammatory mediators such as serum IL-6 and TNF-α were also determined, in addition to histopathological examination of the dissected limbs isolated from all experimental animals. Eighty-one metabolites belonging to different chemical classes were detected in the TEE of P. americana fruit via UPLC/HR-ESI–MS/MS. Two classes of lyso-glycerophospholipids; lyso-glycerophosphoethanolamines and lysoglycerophosphocholines were detected for the first time in avocado fruit in the positive mode. The TEE of fruit exhibited significant antioxidant and anti-inflammatory activity in vitro. In vivo anti-arthritic activity of the fruit TEE improved paw parameters, inflammatory mediators and spleen index. Histopathological findings showed marked improvements in the arthritic condition of the excised limbs. Therefore, avocado fruit could be proposed to be a powerful antioxidant and antiarthritic natural product.

Prospective, randomized single-blind, multicenter comparison of the analgesic efficacy of flurbiprofen/ thiocolchicoside and ibuprofen in myalgia complaints in SARS-CoV-2 patients

Introduction: Myalgia is a common symptom in patients with COVID-19. NSAIDs perform pain suppression mechanisms by suppressing prostaglandin synthesis through inhibition of cyclooxygenase enzyme (COX). Thiocolchicoside activates GABA and Glycine receptors at the spinal level and exerts a myorelaxant effect. The aim of this study is to compare the analgesic efficacy of two drugs, the active ingredients of which are ibuprofen and flurbiprofen/ thiocolchicoside. Method: The study was designed according to a multicenter, prospective, randomized, controlled clinical trial model. A power analysis was performed based on the study of Derosa et al. including patients with myalgia complaints(11). By accepting 80% power and 5% type-1 error, the number of patients to be included in each group was calculated as at least 68. We planned to include 100 patients in each group, taking into account data losses and patients who may drop out of the study during follow-up (n=200). Results: According to the results of the study, the difference between baseline and 2nd day NRS and the difference between baseline and 3rd day NRS were found to be statistically significantly higher in the group using ibuprofen 800 mg retard TB (P<0.05). Conclusion: In the treatment and follow-up of patients with COVID-19 and myalgia complaints, ibuprofen 800 mg retard tb can be preferred primarily because its effectiveness is superior and no side effects are observed.

Virtual screening and invitro evaluation of cyclooxygenase inhibitors from Tinospora cordifolia using the machine learning tool

Tinospora cordifolia has a variety of compounds, and some of these compounds may have anti-inflammatory and antioxidant properties. In the present study, we identified the compounds in the leaf extract of T. cordifolia through Gas Chromatography-Mass Spectrometry (GC-MS) analysis and found the various metabolites. The compounds are screened virtually using a machine learning model, followed by molecular docking and simulation study to identify top-hit compounds as cyclooxygenase (COX) inhibitors. The molecular docking revealed that the compound 7,9-Di-tert-butyl-1-oxaspiro (4,5) deca-6,9-diene-2,8-dione (CID:545303) exhibited the lowest binding energies of −7.1 and −6.8 kcal/mol against COX 1 and COX 2 respectively. The interactions are favored by hydrogen bonding and hydrophobic interaction inside the binding pocket. The 100 ns MD simulation study for these compounds was performed to know the stability and found the RMSD around 2 Å and around 1.0 Å with minimal fluctuations indicating a stable complex throughout the simulation of 100 ns. Based on these findings, we proposed 7,9-Di-tertbutyl- 1-oxaspiro (4,5) deca-6,9-diene-2,8-dione could be used as a dual inhibitor of COX enzymes and a drug-like molecule for treating inflammation after evaluation of their biological properties. The methanolic extract of T. cordifolia was subjected to in vitro DPPH, ABTS, nitric oxide, anti-microbial, COX, and LOX inhibition activity. The results exhibited possible positive effects against the above activities. Communicated by Ramaswamy H. Sarma

Novel Sprayable Thermosensitive Benzydamine Hydrogels for Topical Application: Development, Characterization, and In Vitro Biological Activities.

Benzydamine hydrochloride (BZD) having analgesic, anesthetic, and anti-inflammatory effects is used orally or topically in the treatment of disorders such as joint inflammation and muscle pain. Within the scope of this study, sprayable thermosensitive BZD hydrogels were developed using thermoresponsive poloxamers to avoid systemic side effects and to provide better compliance for topical administration. Also, hydroxypropyl methyl cellulose (HPMC) was employed to improve the mechanical strength and bioadhesive properties of the hydrogel. The addition of BZD generally decreased the viscosity of the formulations (p < 0.05), while increasing the gelation temperature (p < 0.05). The formulations that did not have any clogs or leaks in the nozzle of the bottle during the spraying process were considered lead formulations. To spray the formulations easily, it was found that the viscosity at RT should be less than 200 mPa·s, and their gelation temperature should be between 26 and 34°C. Increasing HPMC and poloxamer improved bioadhesion. The amount of HPMC and poloxamers did not cause a significant change in the release characteristics of the formulations (p > 0.05); the release profiles of BZD from the formulations were similar according to model-independent kinetic (f2 > 50). HPMC and poloxamers had important roles in the accumulation of BZD in the skin. In vitro biological activity studies demonstrated that the formulations presented their anti-inflammatory activity with TNF-α inhibition but did not have any effect on the inhibition of COX enzymes as expected. As a result, thermosensitive hydrogels containing BZD might be an appropriate alternative, providing an advantage in terms of easier application compared to conventional gels.