Cyclooxygenase in normal human tissues--is COX-1 really a constitutive isoform, and COX-2 an inducible isoform?

The Octadecanoids: Synthesis and Bioactivity of 18-Carbon Oxygenated Fatty Acids in Mammals, Bacteria, and Fungi

The octadecanoids are a broad class of lipids consisting of the oxygenated products of 18-carbon fatty acids. Originally referring to production of the phytohormone jasmonic acid, the octadecanoid pathway has been expanded to include products of all 18-carbon fatty acids. Octadecanoids are formed biosynthetically in mammals via cyclooxygenase (COX), lipoxygenase (LOX), and cytochrome P450 (CYP) activity, as well as nonenzymatically by photo- and autoxidation mechanisms. While octadecanoids are well-known mediators in plants, their role in the regulation of mammalian biological processes has been generally neglected. However, there have been significant advancements in recognizing the importance of these compounds in mammals and their involvement in the mediation of inflammation, nociception, and cell proliferation, as well as in immuno- and tissue modulation, coagulation processes, hormone regulation, and skin barrier formation. More recently, the gut microbiome has been shown to be a significant source of octadecanoid biosynthesis, providing additional biosynthetic routes including hydratase activity (e.g., CLA-HY, FA-HY1, FA-HY2). In this review, we summarize the current field of octadecanoids, propose standardized nomenclature, provide details of octadecanoid preparation and measurement, summarize the phase-I metabolic pathway of octadecanoid formation in mammals, bacteria, and fungi, and describe their biological activity in relation to mammalian pathophysiology as well as their potential use as biomarkers of health and disease.

Spatiotemporal characterization of cyclooxygenase pathway enzymes during vertebrate embryonic development

Vertebrate development is regulated by several complex well-characterized morphogen signaling pathways, transcription factors, and structural proteins, but less is known about the enzymatic pathways that regulate early development. We have identified that factors from the inflammation-mediating cyclooxygenase (COX) signaling pathway are expressed at early stages of development in avian embryos. Using Gallus gallus (chicken) as a research model, we characterized the spatiotemporal expression of a subset of genes and proteins in the COX pathway during early neural development stages. Specifically, here we show expression patterns of COX-1, COX-2, and microsomal prostaglandin E synthase-2 (mPGES-2) as well as the genes encoding these enzymes (PTGS1, PTGS2, and PTGES-2). Unique expression patterns of individual players within the COX pathway suggest that they may play non-canonical/non-traditional roles in the embryo compared to their roles in the adult. Future work should examine the function of the COX pathway in tissue specification and morphogenesis and determine if these expression patterns are conserved across species.

Antinociceptive effect of Equisetum arvense extract on the stomatitis hamster model

Recurrent aphthous stomatitis leads to ulcers that cause severe pain, which is a substantial burden on patients. Equisetum arvense extract (EA) is a crude drug that promotes wound healing of mucous membranes caused by perineal incision during childbirth and alleviates pain. Here, we elucidated the effects of EA on wound healing and pain in a stomatitis hamster model. After stomatitis induction, two different EA doses were continuously applied to the wound area through the intramucosal injection of acetic acid into the cheek pouch (stomatitis/100*EA group and stomatitis/EA group). The body weight and wound area were measured over time, and histological evaluation was performed after stomatitis induction. The wound area was harvested 10 h after stomatitis induction, and gene expression associated with pain and inflammation was analyzed using qPCR. The dorsal root ganglia of the rat spinal cord were isolated, dispersed, and cultured to examine the inhibitory effect of EA on the K+-evoked release of neurotransmitter substance P. In the stomatitis/100*EA group, a significant reduction in wound size was observed compared with the stomatitis/physiological saline (PS) group, and the weight gain rate was considerably higher. The stomatitis/EA group revealed similar histological changes in the wound and wound size as the stomatitis/PS group; however, the weight gain rate was considerably higher on day 7. The stomatitis/EA group suppressed the expression of inflammatory cytokine mRNA, such as Tnf-α and Il-6, and Cox-2 mRNA in the wound area compared with the stomatitis/PS group. EA treatment reduced the upregulated substance P release from the dorsal root ganglia following high-concentration K+ stimulation. EA alleviates pain in a stomatitis model by suppressing inflammatory cytokine expression in the wound area and substance P release from primary sensory neurons. Therefore, using oral care products containing EA is expected to suppress stomatitis pain.

Polymer nanotherapeutics with the controlled release of acetylsalicylic acid and its derivatives inhibiting cyclooxygenase isoforms and reducing the production of pro-inflammatory mediators

The effective treatment of inflammatory diseases, particularly their chronic forms, is a key task of modern medicine. Herein, we report the synthesis and evaluation of biocompatible polymer conjugates based on N-2-(hydroxypropyl)methacrylamide copolymers enabling the controlled release of acetylsalicylic acid (ASA)-based anti-inflammatory drugs under specific stimuli. All polymer nanotherapeutics were proposed as water-soluble drug delivery systems with a hydrodynamic size below 10 nm ensuring suitability for the parenteral application and preventing opsonization by the reticuloendothelial system. The nanotherapeutics bearing an ester-bound ASA exhibited long-term release of the ASA/salicylic acid mixture, while the nanotherapeutics carrying salicylic acid hydrazide (SAH) ensured the selective release of SAH in the acidic inflammatory environment thanks to the pH-sensitive hydrazone bond between the polymer carrier and SAH. The ASA- and SAH-containing nanotherapeutics inhibited both cyclooxygenase isoforms and/or the production of pro-inflammatory mediators. Thanks to their favorable design, they can preferentially accumulate in the inflamed tissue, resulting in reduced side effects and lower dosage, and thus more effective and safer treatment.

Distinct etiology of chronic inflammation - implications on degenerative diseases and cancer therapy

Acute inflammation is elicited by lipid and protein mediators in defense of the host following sterile or pathogen-driven injury. A common refrain is that chronic inflammation is a result of incomplete resolution of acute inflammation and behind the etiology of all chronic diseases, including cancer. However, mediators that participate in inflammation are also essential in homeostasis and developmental biology but without eliciting the clinical symptoms of inflammation. This non-inflammatory physiological activity of the so called 'inflammatory' mediators, apparently under the functional balance with anti-inflammatory mediators, is defined as unalamation (un-ala-mation). Inflammation in the absence of injury is a result of perturbance in unalamation due to a decrease in the anti-inflammatory mediators rather than an increase in the inflammatory mediators and leads to chronic inflammation. This concept on the etiology of chronic inflammation suggests that treatment of chronic diseases is better achieved by stimulating the endogenous anti-inflammatory mediators instead of inhibiting the 'inflammatory' mediator biosynthesis with Non-Steroidal Anti-Inflammatory Drugs (NSAIDs). Furthermore, both 'inflammatory' and anti-inflammatory mediators are present at higher concentrations in the tumor microenvironment compared to normal tissue environments. Since cancer is a proliferative disorder rather than a degenerative disease, it is proposed that heightened unalamation, rather than chronic inflammation, drives tumor growth. This understanding helps explain the inefficacy of NSAIDs as anticancer agents. Finally, inhibition of anti-inflammatory mediator biosynthesis in tumor tissues could imbalance unalamation toward local acute inflammation triggering an immune response to restore homeostasis and away from tumor growth.

Real time changes in the expression of eicosanoid synthesizing enzymes during inflammation

Immune responses during inflammation involve complex, well-coordinated lipid signaling pathways. Eicosanoids are a class of lipid signaling molecules derived from polyunsaturated fatty acids such as arachidonic acid and constitute a major network that controls inflammation and its subsequent resolution. Arachidonic acid is metabolized by enzymes in three different pathways to form a variety of lipid metabolites that can be either pro- or anti-inflammatory. Therefore, an understanding of the time-dependent gene expression, lipid metabolite profiles and cytokine profiles during the initial inflammatory response is necessary, as it will allow for the design of time-dependent therapeutics. Herein, we investigate the multi-level regulation of this process. After stimulating RAW 264.7 cells, a mouse-derived macrophage cell line commonly used to examine inflammatory responses, we examine the gene expression of 44 relevant lipid metabolizing enzymes from the different eicosanoid synthesizing classes. We also measure the formation of lipid metabolites and production of cytokines at selected time points. Results reveal a dynamic relationship between the time-course of inflammation dependent gene expression of the three eicosanoid synthesizing enzymes.

Pharmacokinetics of aspirin: evaluating shortcomings in the literature

INTRODUCTION

Aspirin is known for its therapeutic benefits in preventing strokes and relieving pain. However, it is toxic to some individuals, and the biological mechanisms causing toxicity are unknown. Limited literature is available on the role of glycine conjugation as the principal pathway in aspirin detoxification. Previous studies have quantified this two-step enzyme reaction as a singular enzymatic process. Consequently, the individual contributions of these enzymes to the kinetics remain unclear.

AREAS COVERED

This review summarized the available information on the pharmacokinetics and detoxification of aspirin by the glycine conjugation pathway. Literature searches were conducted using Google Scholar and the academic journal databases accessible through the North-West University Library. Furthermore, the factors affecting interindividual variation in aspirin metabolism and what is known regarding aspirin toxicity were discussed.

EXPERT OPINION

The greatest drawback in understanding the pharmacokinetics of aspirin is the limited information available on the substrate preference of the xenobiotic ligase (ACSM) responsible for activating salicylate to salicyl-CoA. Furthermore, previous pharmacokinetic studies did not consider the contribution of other substrates from the diet or genetic variants, to the detoxification rate of glycine conjugation. Impaired glycine conjugation might contribute to adverse health effects seen in Reye's syndrome and cancer.

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.

Seagrass as a potential nutraceutical to decrease pro-inflammatory markers

BACKGROUND

The Pro-inflammatory mediators such as prostaglandin E2, nitric oxide and TNF-α are the key players in the stimulation of the inflammatory responses. Thus, the pro-inflammatory mediators are considered to be potential targets for screening nutraceutical with anti-inflammatory activity.

METHODS

In this context, we explored the anti-inflammatory potency of seagrass extract with western blot (Bio-Rad) analysis by using LPS induced RAW macrophages as in-vitro models, western blot analysis, In-silico methods using Mastero 13.0 software.

RESULTS

The anti-inflammatory activity of Seagrass was demonstrated through down regulation of Pro-inflammatory markers such as Cyclooxygenase-2, induced Nitric oxide synthase and prostaglandin E synthase-1. The results were validated by docking the phytochemical constituents of seagrass namely Isocoumarin, Hexadecanoic acid, and Cis-9 Octadecenoic acid, 1,2 Benzene dicarboxylic acid and beta-sitosterol with TNF-alpha, COX-2, iNOS and PGES-1.

CONCLUSION

The methanolic extract of seagrass Halophila beccarii is a potential nutraceutical agent for combating against inflammation with a significant anti-inflammatory activity.

CYP2J2-mediated metabolism of arachidonic acid in heart: A review of its kinetics, inhibition and role in heart rhythm control

Cytochrome P450 2 J2 (CYP2J2) is primarily expressed extrahepatically and is the predominant epoxygenase in human cardiac tissues. This highlights its key role in the metabolism of endogenous substrates. Significant scientific interest lies in cardiac CYP2J2 metabolism of arachidonic acid (AA), an omega-6 polyunsaturated fatty acid, to regioisomeric bioactive epoxyeicosatrienoic acid (EET) metabolites that show cardioprotective effects including regulation of cardiac electrophysiology. From an in vitro perspective, the accurate characterization of the kinetics of CYP2J2 metabolism of AA including its inhibition and inactivation by drugs could be useful in facilitating in vitro-in vivo extrapolations to predict drug-AA interactions in drug discovery and development. In this review, background information on the structure, regulation and expression of CYP2J2 in human heart is presented alongside AA and EETs as its endogenous substrate and metabolites. The in vitro and in vivo implications of the kinetics of this endogenous metabolic pathway as well as its perturbation via inhibition and inactivation by drugs are elaborated. Additionally, the role of CYP2J2-mediated metabolism of AA to EETs in cardiac electrophysiology will be expounded.

Toxic effects of environmental concentration Bisphenol AF exposure on the survival, growth and reproduction of adult male Oryzias curvinotus

Bisphenol AF (BPAF) is a novel environmental endocrine disruptor, and is widely detected in the aquatic environment, which is a potential threat to the health of fish. In this study, male Oryzias curvinotus were exposed to environmental concentrations (0.93 and 9.33 μg/L) of BPAF for 21 days. The effects of BPAF on survival, growth, reproduction, liver and testis histology, and gene transcriptional profiles of O. curvinotus were investigated. The results showed that the survival rate of male O. curvinotus slight decrease with increasing BPAF concentration, and there was no significant effect on body length, body weight, and K-factor. BPAF (9.33 μg/L) caused significant changes in testicular structure and reduced spermatid count in O. curvinotus. Changes in transcript levels of some antioxidant-related genes in gills and liver following BPAF exposure, imply an effect of BPAF on the immune system. After BPAF exposure, chgs and vtgs were up-regulated, validating the estrogenic effect of BPAF. In the hypothalamic - pituitary - gonadal axis (HPG) results, erα, erγ and cyp19a1b were all up-regulated in the brain, and the 0.93 μg/L BPAF group was more up-regulated than the 9.33 μg/L BPAF group. In testis, BPAF significantly up-regulated the mRNA expression level of cyp17a1 and cyp11b, while significantly down-regulated mRNA expression level of cyp11a, and cyp19a1 was significantly down-regulated only in the 0.93 μg/L BPAF group. In conclusion, environmental levels of BPAF have adverse effects on the survival and reproduction of O. curvinotus, and the potential toxic effects of environmental levels of BPAF cannot be ignored.

Therapeutic potential of ginseng leaf extract in inhibiting mast cell-mediated allergic inflammation and atopic dermatitis-like skin inflammation in DNCB-treated mice

Ginseng leaves are known to contain high concentrations of bioactive compounds, such as ginsenosides, and have potential as a treatment for various conditions, including fungal infections, cancer, obesity, oxidative stress, and age-related diseases. This study assessed the impact of ginseng leaf extract (GLE) on mast cell-mediated allergic inflammation and atopic dermatitis (AD) in DNCB-treated mice. GLE reduced skin thickness and lymph node nodules and suppressed the expression and secretion of histamine and pro-inflammatory cytokines. It also significantly lowered the production of inflammatory response mediators including ROS, leukotriene C4 (LTC4), prostaglandin E2 (PGE2), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS). GLE inhibited the phosphorylation of MAPKs (ERK, P38, JNK) and the activation of NF-κB, which are both linked to inflammatory cytokine expression. We demonstrated that GLE's inhibitory effect on mast cell-mediated allergic inflammation is due to the blockade of the NF-κB and inflammasome pathways. Our findings suggest that GLE can be an effective therapeutic agent for mast-cell mediated and allergic inflammatory conditions.

Neuroinflammation in Neurodegenerative Disorders: Current Knowledge and Therapeutic Implications

Neurodegenerative disorders (NDs) have become increasingly common during the past three decades. Approximately 15% of the total population of the world is affected by some form of NDs, resulting in physical and cognitive disability. The most common NDs include Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, and Huntington's disease. Although NDs are caused by a complex interaction of genetic, environmental, and lifestyle variables, neuroinflammation is known to be associated with all NDs, often leading to permanent damage to neurons of the central nervous system. Furthermore, numerous emerging pieces of evidence have demonstrated that inflammation not only supports the progression of NDs but can also serve as an initiator. Hence, various medicines capable of preventing or reducing neuroinflammation have been investigated as ND treatments. While anti-inflammatory medicine has shown promising benefits in several preclinical models, clinical outcomes are often questionable. In this review, we discuss various NDs with their current treatment strategies, the role of neuroinflammation in the pathophysiology of NDs, and the use of anti-inflammatory agents as a potential therapeutic option.

Molecular Mechanism of Resveratrol and Its Therapeutic Potential on Female Infertility

Resveratrol is a polyphenol present in various plant sources. Studies have reported numerous potential health benefits of resveratrol, exhibiting anti-aging, anti-inflammatory, anti-microbial, and anti-carcinogenic activity. Due to the reported effects, resveratrol is also being tested in reproductive disorders, including female infertility. Numerous cellular, animal, and even human studies were performed with a focus on the effect of resveratrol on female infertility. In this review, we reviewed some of its molecular mechanisms of action and summarized animal and human studies regarding resveratrol and female infertility, with a focus on age-related infertility, polycystic ovary syndrome, and endometriosis.

Cold-induced changes in plasma signaling lipids are associated with a healthier cardiometabolic profile independently of brown adipose tissue

Cold exposure activates brown adipose tissue (BAT) and potentially improves cardiometabolic health through the secretion of signaling lipids by BAT. Here, we show that 2 h of cold exposure in young adults increases the levels of omega-6 and omega-3 oxylipins, the endocannabinoids (eCBs) anandamide and docosahexaenoylethanolamine, and lysophospholipids containing polyunsaturated fatty acids. Contrarily, it decreases the levels of the eCBs 1-LG and 2-LG and 1-OG and 2-OG, lysophosphatidic acids, and lysophosphatidylethanolamines. Participants overweight or obese show smaller increases in omega-6 and omega-3 oxylipins levels compared to normal weight. We observe that only a small proportion (∼4% on average) of the cold-induced changes in the plasma signaling lipids are slightly correlated with BAT volume. However, cold-induced changes in omega-6 and omega-3 oxylipins are negatively correlated with adiposity, glucose homeostasis, lipid profile, and liver parameters. Lastly, a 24-week exercise-based randomized controlled trial does not modify plasma signaling lipid response to cold exposure.

Non-steroidal anti-inflammatory drugs and risk of pulmonary embolism in patients with inflammatory joint disease-results from the nationwide Norwegian Cardio-rheuma registry

AIMS

Patients with inflammatory joint diseases (IJD), including rheumatoid arthritis (RA), psoriatic arthritis (PsA), and axial spondyloarthritis (axSpA) have increased rates of pulmonary embolism (PE). Non-steroidal anti-inflammatory drugs (NSAIDs) use is associated with PE in the general population. Our aim was to evaluate the association between NSAIDs use and PE in IJD patients.

METHODS AND RESULTS

Using individual-level registry data from the whole Norwegian population, including data from the Norwegian Patient Registry and the Norwegian Prescription Database, we: (1) evaluated PE risk in IJD compared to non-IJD individuals, (2) applied the self-controlled case series method to evaluate if PE risks were associated with use of traditional NSAIDs (tNSAIDs) and selective cox-2 inhibitors (coxibs). After a one-year wash-out period, we followed 4 660 475 adults, including 74 001 with IJD (RA: 39 050, PsA: 20 803, and axSpA: 18 591) for a median of 9.0 years. Crude PE incidence rates per 1000 patient years were 2.02 in IJD and 1.01 in non-IJD individuals. Age and sex adjusted hazard ratios for PE events were 1.57 for IJD patients compared to non-IJD. Incidence rate ratios (IRR) [95% confidence interval (CI)] for PE during tNSAIDs use were 0.78 (0.64-0.94, P = 0.010) in IJD and 1.68 (1.61-1.76, P < 0.001) in non-IJD. IRR (95% CI) for PE during coxibs use was 1.75 (1.10-2.79, P = 0.018) in IJD and 2.80 (2.47-3.18, P < 0.001) for non-IJD.

CONCLUSION

Pulmonary embolism rates appeared to be higher in IJD than among non-IJD subjects in our study. Traditional NSAIDs may protect against PE in IJD patients, while coxibs may associated with increased PE risk.

In-silico based Designing of benzo[d]thiazol-2-amine Derivatives as Analgesic and Anti-inflammatory Agents

BACKGROUND

Benzo[d]thiazoles represent a significant class of heterocyclic compounds renowned for their diverse pharmacological activities, including analgesic and antiinflammatory properties. This molecular scaffold holds substantial interest among medicinal chemists owing to its structural versatility and therapeutic potential. Incorporating the benzo[d]thiazole moiety into drug molecules has been extensively investigated as a strategy to craft novel therapeutics with heightened efficacy and minimized adverse effects.

AIMS

The aim of the present research work was to design, synthesize and characterize the new benzo[d]thiazol-2-amine derivatives as potent analgesic and anti-inflammatory agents.

MATERIALS AND METHODS

The synthesis of the presented benzo[d]thiazol-2-amine derivatives was performed by condensing-(4-chlorobenzylidene) benzo[d]thiazol-2-amine with a number of substituted phenols in the presence of potassium iodide and anhydrous potassium carbonate in dry acetone. IR spectroscopy, 1HNMR spectroscopy, 13CNMR spectroscopy and Mass spectroscopy methods were used to characterize the structural properties of all 13 newly synthesized derivatives. The molecular properties of these newly synthesized derivatives were estimated to study the attributes of drug-like candidates. Benzo[d]thiazol-2-amine derivatives were molecularly docked with selective enzymes COX-1 and COX-2. Analgesic and anti-inflammatory activities of synthesized compounds were evaluated by using albino rats.

RESULTS

Findings of the research suggested that compounds G3, G4, G6, G8 and G11 possess higher binding affinity than diclofenac sodium, when docking was performed with enzyme COX-1. Compounds G1, G3, G6, G8 and G10 showed lower binding affinity than Indomethacin when docking was performed with enzyme COX-2. In vitro evaluation of the COX-1 and COX-2 enzyme inhibitory activities was performed for synthesized compounds.

DISCUSSION

Compounds G10 and G11 exhibited significant COX-1 and COX-2 enzyme inhibitory action with an IC50 value of 5.0 and 10 μM, respectively. Using the hot plate method and the carrageenan-induced rat paw edema model, the synthesized compounds were screened for their biological activities, including analgesic and anti-inflammatory activities. Highest analgesic action was exhibited by derivative G11 and the compound G10 showed the highest anti-inflammatory response. Inhibition of COX may be considered as a mechanism of action of these compounds.

CONCLUSION

It was concluded that synthesized derivatives G10 and G11 exhibited significant analgesic and anti-inflammatory effect; therefore, the said compounds may be subjected to further clinical investigation for establishing these as future compounds for the treatment of pain and inflammation.

Sex-specific effects of a high fat diet on aortic inflammation and dysfunction

Obesity and vascular dysfunction are independent and sexually dimorphic risk factors for cardiovascular disease. A high fat diet (HFD) is often used to model obesity in mice, but the sex-specific effects of this diet on aortic inflammation and function are unclear. Therefore, we characterized the aortic immune cell profile and function in 6-week-old male and female C57BL/6 mice fed a normal chow diet (NCD) or HFD for 10 weeks. Metabolic parameters were measured weekly and fortnightly. At end point, aortic immune cell populations and endothelial function were characterized using flow cytometry and wire myography. HFD-male mice had higher bodyweight, blood cholesterol, fasting blood glucose and plasma insulin levels than NCD mice (P < 0.05). HFD did not alter systolic blood pressure (SBP), glycated hemoglobin or blood triglycerides in either sex. HFD-females had delayed increases in bodyweight with a transient increase in fasting blood glucose at week 8 (P < 0.05). Flow cytometry revealed fewer proinflammatory aortic monocytes in females fed a HFD compared to NCD. HFD did not affect aortic leukocyte populations in males. Conversely, HFD impaired endothelium-dependent vasorelaxation, but only in males. Overall, this highlights biological sex as a key factor determining vascular disease severity in HFD-fed mice.

Pyridazine derivatives as selective COX-2 inhibitors: A review on recent updates

Selective cyclooxygenase (COX)-2 inhibitors have several advantages over nonselective COX inhibitors (nonsteroidal anti-inflammatory drugs [NSAIDs]), including the absence of adverse effects (renal and hepatic disorders) associated with the long-term use of standard NSAIDs, as well as an improved gastrointestinal profile. The pyridazine nucleus is regarded as a promising scaffold for the development of powerful COX-2 inhibitors, particularly when selectively functionalized. This article summarizes some methods for the synthesis of pyridazine derivatives. Furthermore, it covers all of the pyridazine derivatives that have appeared as selective COX-2 inhibitors, making it useful as a reference for the rational design of novel selective COX-2 inhibitors.

Phytochemical profiling, in vitro analysis for anti-inflammatory, immunomodulatory activities, structural elucidation and in silico evaluation of potential selective COX-2 and TNF-α inhibitor from Hydrilla verticillata (L.f.) Royle

Hydrilla verticillata (L.f.) Royle is a perennial aquatic plant, which exhibits nutritional as well as therapeutic properties. The present study has been carried out to evaluate anti-inflammatory and immunomodulatory activities along with in silico evaluation of potential selective COX-2 and TNF-α inhibitors from methanolic extract of H. verticillata (L.f.) Royle. The potential therapeutic compounds have been identified by high-resolution GC-MS analysis. Its capacity to inhibit inflammatory responses using lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells has been explored. The anti-inflammatory properties of the plant extract were investigated by inhibiting inducible nitric oxide (NO) synthase and reduced NO generation driven by LPS on stimulated RAW 264.7 macrophage cells. Further investigation for the underlying molecular mechanism of the anti-inflammatory activity of plant extract has been carried out by molecular docking and molecular dynamics simulation approaches with COX-2 and TNF-α inhibitors ability against the most potent phytocompound phytol from the plant extract. To evaluate whether the extract causes any toxicity, the cytotoxicity test has been carried out with the Human embryonic kidney cell line (Hek-293), Mouse fibroblast (L929), human mesenchyme stem cells (hMSCs) and human breast epithelial cell line (MCF-10a). Ultimately, our findings suggest that the plant extract have great potential to reduce inflammation without causing any toxicity to normal cell.Communicated by Ramaswamy H. Sarma.

Neutralizing tumor-related inflammation and reprogramming of cancer-associated fibroblasts by Curcumin in breast cancer therapy

Tumor-associated inflammation plays a vital role in cancer progression. Among the various stromal cells, cancer-associated fibroblasts are promising targets for cancer therapy. Several reports have indicated potent anti-inflammatory effects attributed to Curcumin. This study aimed to investigate whether inhibiting the inflammatory function of cancer-associated fibroblasts (CAFs) with Curcumin can restore anticancer immune responses. CAFs were isolated from breast cancer tissues, treated with Curcumin, and co-cultured with patients' PBMCs to evaluate gene expression and cytokine production alterations. Blood and breast tumor tissue samples were obtained from 12 breast cancer patients with stage II/III invasive ductal carcinoma. Fibroblast Activation Protein (FAP) + CAFs were extracted from tumor tissue, treated with 10 μM Curcumin, and co-cultured with corresponding PBMCs. The expression of smooth muscle actin-alpha (α-SMA), Cyclooxygenase-2(COX-2), production of PGE2, and immune cell cytokines were evaluated using Real-Time PCR and ELISA, respectively. Analyzes showed that treatment with Curcumin decreased the expression of genes α-SMA and COX-2 and the production of PGE2 in CAFs. In PBMCs co-cultured with Curcumin-treated CAFs, the expression of FoxP3 decreased along with the production of TGF-β, IL-10, and IL-4. An increase in IFN-γ production was observed that followed by increased T-bet expression. According to our results, Curcumin could reprogram the pro-tumor phenotype of CAFs and increase the anti-tumor phenotype in PBMCs. Thus, CAFs, as a component of the tumor microenvironment, are a suitable target for combination immunotherapies of breast cancer.

A high throughput method for detection of cyclooxygenase-2 enzyme inhibitors by effect-directed analysis applying high performance thin layer chromatography-bioassay-mass spectrometry

A high throughput method was developed to detect bioactive molecules with inhibitory activity over cyclooxygenase (COX-2) enzyme applying effect-directed analysis and planar chromatography hyphenated with bioassay and mass spectrometry. The assay was based on the indirect measurement of arachidonic acid transformation into prostaglandin with the colorimetric co-substrate N,N,N',N'-tetramethyl-p-phenylenediamine. Inhibitory zones were observed as colorless bands over a blue background. Using a central composite design the critical factors like substrate concentration, enzyme: substrate ratio, reaction time, and co-substrate concentration were optimized. Optimal conditions were achieved with 0.03 mg/mL of arachidonic acid, 0.15 U/mL of COX-2, and 8.21 mg/mL of chromogenic reagent. Method usefulness was challenged analyzing fresh Chiloe's giant garlic (Allium ampeloprasum L) ethanol: water (8:2 v/v) extract, finding COX-2 inhibitors that were preliminarily identified as the isomers γ-glutamyl-S-allyl-l-cysteine and γ-glutamyl-S-(trans-1-propenyl)-L- cysteine.

Gastroprotective Role of Fruit Extracts in Gastric Damage Induced by Non-Steroidal Anti-Inflammatory Drugs: A Systematic Review

The aim of this study was to systematically review the scientific literature, with Preferred Reporting Items of Systematic Reviews and Meta-analyses (PRISMA) guidelines, of the articles found in the past 11 years on the gastroprotective role of fruit extracts in gastric ulcers induced by non-steroidal anti-inflammatory drugs (NSAIDs). Scientific articles published between 2010 and 2020 were included in this systematic review, including in vitro and in vivo models, to define the gastroprotective role of fruit extracts. Studies were selected by Rayyan using PubMed, Web of Science, Scopus, and Science Direct databases. The keywords for the search strategy were: "gastric injury," "gastric ulcer," "fruit," "indomethacin," and "aspirin." Twenty-two articles with animal models of gastric ulcers were included. The NSAIDs used were aspirin and indomethacin. To know the damage caused by these, the ulceration index and biomarkers, such as aggressive/defensive factors involved in the gastric ulceration process, were measured. Most studies have shown that fruit extracts have antiulcer activity, with the most abundant metabolites being flavonoids, followed by terpenes and alkaloids. Possible antiulcer activities such as antioxidant, cytoprotective, gastric acid antisecretory, anti-inflammatory, or angiogenesis stimulant were declared, manifested mainly as a reduction of lipid peroxidation products, an increase in antioxidant enzymes and prostaglandins, and by the formation of a protective film through protein precipitation in the ulcer area. This systematic review demonstrates the importance of fruit extracts as gastric protectors.

The crucial role that hippocampus Cyclooxygenase-2 plays in memory

It is generally accepted that Cyclooxygenase-2 (COX-2) is activated to cause inflammation. However, COX-2 is also constitutively expressed at the postsynaptic dendrites and excitatory terminals of the cortical and spinal cord neurons. Although some evidence suggests that COX-2 release during neuronal signalling may be pivotal for regulating the function of memory, the significance of constitutively expressed COX-2 in neuron is still unclear. This research aims to discover the role of COX-2 in memory beyond neuroinflammation and to determine whether the inhibition of COX-2 can cause cognitive dysfunction by influencing dendritic plasticity and its underlying mechanism. We found COX-2 gene knockout (KO) could significantly impact the learning and memory ability, cause neuronal structure disorder and influence gamma oscillations. These might be mediated by the inhibition of prostaglandin (PG) E2/cAMP pathway and phosphorylated protein kinase A (p-PKA)-phosphorylated cAMP response element binding protein (p-CREB)-brain derived neurotrophic factor (BDNF) axis. It suggested COX-2 might play a critical role in learning, regulating neuronal structure and gamma oscillations in the hippocampus CA1 by regulating COX-2/BDNF signalling pathway.

Characteristics of adverse drug reactions due to nonsteroidal anti-inflammatory drugs: a cross-sectional study

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used for treating pain and inflammation. Spontaneous adverse drug reaction (ADR) reports represent a rich data source for the detection of unknown and rare ADRs. This cross-sectional study aimed to analyze the characteristics of ADRs due to NSAIDs in Thailand. All ADR reports of NSAIDs for systemic use from 2015 to 2019 were extracted from the national database in Thailand. Patient characteristics, drug use information, adverse event information, and source of senders in 32,857 reports were analyzed. The annual number of ADR reports due to NSAIDs decreased from 7,008 in 2015 to 5,922 in 2019. The most frequently reported drug was ibuprofen (n=12,645, 38.5%) followed by diclofenac (n=7,795, 23.7%), most patients were 40-59 years old, and the major adverse reaction was angioedema (n=7,513, 22.9%). Serious reactions were recorded in 20.7% (n=6,801) of the total ADRs. Most patients (n=20,593, 62.7%) recovered without sequelae, but there were 5,420 patients (16.5%) who could not recover and 3,109 patients (9.5%) who were recovering. Eight patients (0.02%) died of Stevens-Johnson syndrome (n=3), toxic epidermal necrolysis (n=4), and anaphylactic shock (n=1), which were possibly related to ADRs. The number of ADR reports due to NSAIDs decreased from 2015 to 2019 in Thailand. Serious ADRs and death cases accounted for 20.7% and 0.02%, respectively. Most fatal cases exhibited severe drug-induced skin reactions.

Protocatechuic Acid and Syringin from Saussurea neoserrata Nakai Attenuate Prostaglandin Production in Human Keratinocytes Exposed to Airborne Particulate Matter

Saussurea neoserrata Nakai offers a reliable and efficient source of antioxidants that can help alleviate adverse skin reactions triggered by air pollutants. Air pollutants, such as particulate matter (PM), have the ability to infiltrate the skin and contribute to the higher occurrence of cardiovascular, cerebrovascular, and respiratory ailments. Individuals with compromised skin barriers are particularly susceptible to the impact of PM since it can be absorbed more readily through the skin. This study investigated the impact of protocatechuic acid and syringin, obtained from the n-BuOH extract of S. neoserrata Nakai, on the release of PGE₂ and PGD₂ induced by PM₁₀. Additionally, it examined the gene expression of the synthesis of PGE₂ and PGD₂ in human keratinocytes. The findings of this research highlight the potential of utilizing safe and efficient plant-derived antioxidants in dermatological and cosmetic applications to mitigate the negative skin reactions caused by exposure to air pollution.

Comparative structural study of selective and non-selective NSAIDs against the enzyme cyclooxygenase-2 through real-time molecular dynamics linked to post-dynamics MM-GBSA and e-pharmacophores mapping

BACKGROUND

Inflammation-provoked disorders including cancer are arbitrated by cyclooxygenase-2 (COX-2). Celecoxib and niflumic acid are among the potent and selective inhibitors of this enzyme while aspirin (acetylsalicylic acid) and sodium salicylate are its non-selective and lesser potent inhibitors. Despite these proven studies, the comparative structural study of these selective and non-selective molecules at atomistic scale in complex state with COX-2 that may answer this differential inhibitory behavior has not been accomplished spotlighting the imperative need of additional research in this area. Thus, this study was framed to provide a strong explanation for the enigma of higher inhibitory activity of celecoxib-niflumic acid duo in comparison to aspirin and sodium salicylate towards COX-2.

METHODS

A contemporary approach including advanced molecular docking against COX2, molecular dynamics of receptor-ligand complexes, simulation-trajectory-backed MMGBSA for different time points, radius of gyration (Rg) calculations, and e-pharmacophores approach was employed to attain a rational conclusion.

RESULTS

Our findings demonstrated the higher binding affinity of celecoxib and niflumic acid over aspirin and sodium salicylate against COX-2. Although both selective and non-selective COX-2 inhibitors manifested nearly the same stability in the active site of this enzyme but the e-pharmocophoric features found in the case of selective inhibitors scored over non-selective ones. Thus, our findings excluded the differential stability to be the cause of stronger potency of selective inhibitors but attributed their potency to greater number of complementary features present in these inhibitors against the active site of inflammation engendering COX-2.

Rapid and sensitive determination of Piroxicam by N-doped carbon dots prepared by plant soot

Piroxicam (PX) as a nonsteroidal anti-inflammatory drug (NSAID) can be effectively used for anti-inflammatory and analgesia. However, overdoses may induce side effects such as gastrointestinal ulcers and headaches. Therefore, the assay of piroxicam has considerable significance. In this work, nitrogen-doped carbon dots (N-CDs) was synthesized for PX detection. The fluorescence sensor was fabricated by hydrothermal method with plant soot and ethylenediamine. The strategy exhibited a detection range of 6-200 μg/mL and 250-700 μg/mL with the limited detection of 2 μg/mL. The mechanism of the PX assay base on the fluorescence sensor was the process of electron transfer between the PX and N-CDs. The assay subsequently demonstrated could be successfully used in actual sample. The results indicated that the N-CDs could be a superior candidate nanomaterial for piroxicam monitoring in the healthcare product industry.

Acute and sub-acute dermal toxicity of meloxicam emulgel: Analysis of biochemical, hematological, histopathological and immunohistochemical expression

Meloxicam, a non-steroidal anti-inflammatory drug (NSAID) for the treatment of osteoarthritis. Despite being more effective against pain mediated by inflammation, it is associated with gastrointestinal, cardiovascular, and renal toxicity. In the current study, acute single-dose (2000 mg/kg) and subacute (500, 1000, and 2000 mg kg^-1 for 28 days) dermal toxicity analyses of meloxicam emulgel were conducted in Wistar rats. Various biochemical, hematological, histopathological and immunohistochemical parameters were evaluated. The dermal LD₅₀ (lethal dose) of meloxicam emulgel was found to be > 2000 mg/kg. No significant adverse effects of meloxicam emulgel following topical administration in subacute toxicity studies were noticed. IL-1β was not expressed post treatment with meloxicam emulgel. IL-1β is an influential pro-inflammatory cytokine that is decisive for host-defence consequence to injury and infection. Therefore, using data gleaned from the extant study, topical administration of meloxicam emulgel may be regarded as safe as the "no observed adverse effect level" (NOAEL) was >2000 mg/kg in experimental animals.

COX Isozymes and Non-Uniform Neoangiogenesis: What is their role in Endometriosis?

This literature review compared the efficacy in of NSAIDs with a placebo in pain relief and disease regression of endometriosis. Despite the poor evidence found, the results showed that NSAIDs were more effective in pain relief with regressive effects on the endometriotic lesions compared to placebo. We postulate herein that COX-2 is chiefly responsible for pain whilst COX-1 is responsible mainly for the establishment of endometriotic lesions. Hence, there must be a temporal difference in the activation of the two isozymes. We differentiated between two pathways in the conversion of arachidonic acid to prostaglandins by the COX isozymes referred to as 'direct' and indirect', supporting our initial theory. Finally, we postulate that there are two stages of neoangiogenesis in the formation of endometriotic lesions; 'founding' that first establishes blood supply and 'maintenance' that upkeeps it This is fertile ground for further research in a niche that needs more literature. Its aspects may be diversely explored. The theories we propose offer information for a more targeted treatment of endometriosis.

Development of a COX-2-Selective Fluorescent Probe for the Observation of Early Intervertebral Disc Degeneration

Cyclooxygenase-2 (COX-2) is a biomolecule known to be overexpressed in inflammation. Therefore, it has been considered a diagnostically useful marker in numerous studies. In this study, we attempted to assess the correlation between COX-2 expression and the severity of intervertebral disc (IVD) degeneration using a COX-2-targeting fluorescent molecular compound that had not been extensively studied. This compound, indomethacin-adopted benzothiazole-pyranocarbazole (IBPC1), was synthesized by introducing indomethacin—a compound with known selectivity for COX-2—into a phosphor with a benzothiazole-pyranocarbazole structure. IBPC1 exhibited relatively high fluorescence intensity in cells pretreated with lipopolysaccharide, which induces inflammation. Furthermore, we observed significantly higher fluorescence in tissues with artificially damaged discs (modeling IVD degeneration) compared to normal disc tissues. These findings indicate that IBPC1 can meaningfully contribute to the study of the mechanism of IVD degeneration in living cells and tissues and to the development of therapeutic agents.

Design, synthesis, molecular docking studies and biological evaluation of thiazole carboxamide derivatives as COX inhibitors

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) have been the most commonly used class of medications worldwide for the last three decades.

OBJECTIVES

This study aimed to design and synthesize a novel series of methoxyphenyl thiazole carboxamide derivatives and evaluate their cyclooxygenase (COX) suppressant and cytotoxic properties.

METHODS

The synthesized compounds were characterized using ¹H, ¹³C-NMR, IR, and HRMS spectrum analysis and were evaluated for their selectivity towards COX-1 and COX-2 using an in vitro COX inhibition assay kit. Besides, their cytotoxicity was evaluated using the Sulforhodamine B (SRB) assay. Moreover, molecular docking studies were conducted to identify the possible binding patterns of these compounds within both COX-1 and COX-2 isozymes, utilizing human X-ray crystal structures. The density functional theory (DFT) analysis was used to evaluate compound chemical reactivity, which was determined by calculating the frontier orbital energy of both HOMO and LUMO orbitals, as well as the HOMO-LUMO energy gap. Finally, the QiKProp module was used for ADME-T analysis.

RESULTS

The results revealed that all synthesized molecules have potent inhibitory activities against COX enzymes. The percentage of inhibitory activities at 5 µM concentration against the COX2 enzyme was in the range of 53.9-81.5%, while the percentage against the COX-1 enzyme was 14.7-74.8%. That means almost all of our compounds have selective inhibition activities against the COX-2 enzyme, and the most selective compound was 2f, with selectivity ratio (SR) value of 3.67 at 5 µM concentration, which has a bulky group of trimethoxy on the phenyl ring that could not bind well with the COX-1 enzyme. Compound 2h was the most potent, with an inhibitory activity percentage at 5 µM concentration of 81.5 and 58.2% against COX-2 and COX-1, respectively. The cytotoxicity of these compounds was evaluated against three cancer cell lines: Huh7, MCF-7, and HCT116, and negligible or very weak activities were observed for all of these compounds except compound 2f, which showed moderate activities with IC₅₀ values of 17.47 and 14.57 µM against Huh7 and HCT116 cancer cell lines, respectively. Analysis of the molecular docking suggests 2d, 2e, 2f, and 2i molecules were bound to COX-2 isozyme favorably over COX-1 enzyme, and their interaction behaviors within COX-1 and COX-2 isozymes were comparable to celecoxib, as an ideal selective COX-2 drug, which explained their high potency and COX-2 selectivity. The molecular docking scores and expected affinity using the MM-GBSA approach were consistent with the recorded biological activity. The calculated global reactivity descriptors, such as HOMO and LUMO energies and the HOMO-LUMO gaps, confirmed the key structural features required to achieve favorable binding interactions and thus improve affinity. The in silico ADME-T studies asserted the druggability of molecules and have the potential to become lead molecules in the drug discovery process.

CONCLUSION

In general, the series of the synthesized compounds had a strong effect on both enzymes (COX-1 and COX-2) and the trimethoxy compound 2f was more selective than the other compounds.

The roles of COX-2 in protozoan infection

Protozoan diseases cause great harm in animal husbandry and require human-provided medical treatment. Protozoan infection can induce changes in cyclooxygenase-2 (COX-2) expression. The role played by COX-2 in the response to protozoan infection is complex. COX-2 induces and regulates inflammation by promoting the synthesis of different prostaglandins (PGs), which exhibit a variety of biological activities and participate in pathophysiological processes in the body in a variety of ways. This review explains the roles played by COX-2 in protozoan infection and analyzes the effects of COX-2-related drugs in protozoan diseases.

Natural-Derived COX-2 Inhibitors as Anticancer Drugs: A Review of their Structural Diversity and Mechanism of Action

Cyclooxygenase-2 (COX-2) is a key-type enzyme playing a crucial role in cancer development, making it a target of high interest for drug designers. In the last two decades, numerous selective COX-2 inhibitors have been approved for various clinical conditions. However, data from clinical trials propose that the prolonged use of COX-2 inhibitors is associated with life-threatening cardiovascular side effects. The data indicate that a slight structural modification can help develop COX-2 selective inhibitors with comparative efficacy and limited side effects. In this regard, secondary metabolites from natural sources offer great hope for developing novel COX-2 inhibitors with potential anticancer activity. In recent years, various nature-derived organic scaffolds are being explored as leads for developing new COX-2 inhibitors. The current review attempts to highlight the COX-2 inhibition activity of some naturally occurring secondary metabolites, concerning their capacity to inhibit COX-1 and COX-2 enzymes and inhibit cancer development, aiming to establish a structure-activity relationship.

Association between inflammation, reward processing, and ibuprofen-induced increases of miR-23b in astrocyte-enriched extracellular vesicles: A randomized, placebo-controlled, double-blind, exploratory trial in healthy individuals

Ibuprofen, a non-steroidal, anti-inflammatory drug, modulates inflammation but may also have neuroprotective effects on brain health that are poorly understood. Astrocyte-enriched extracellular vesicles (AEEVs) facilitate cell-to-cell communication and - among other functions - regulate inflammation and metabolism via microribonucleic acids (miRNAs). Dysfunctions in reward-related processing and inflammation have been proposed to be critical pathophysiological pathways in individuals with mood disorders. This investigation examined whether changes in AEEV cargo induced by an anti-inflammatory agent results in inflammatory modulation that is associated with reward-related processing. Data from a double-blind, randomized, repeated-measures study in healthy volunteers were used to examine the effects of AEEV miRNAs on brain activation during reward-related processing. In three separate visits, healthy participants (N = 20) received a single dose of either placebo, 200 mg, or 600 mg of ibuprofen, completed the monetary incentive delay task during functional magnetic resonance imaging, and provided a blood sample for cytokine and AEEV collection. AEEV miRNA content profiling showed that ibuprofen dose-dependently increased AEEV miR-23b-3p expression with greater increase following the 600 mg administration than placebo. Those individuals who received 600 mg and showed the highest miR-23b-3p expression also showed the (a) lowest serum tumor necrosis factor (TNF) and interleukin-17A (IL-17A) concentrations; and had the (b) highest striatal brain activation during reward anticipation. These results support the hypothesis that ibuprofen alters the composition of miRNAs in AEEVs. This opens the possibility that AEEV cargo could be used to modulate brain processes that are important for mental health.

A monoclonal antibody against a Leishmania mexicana COX-like enzymatic activity also recognizes similar proteins in different protozoa of clinical importance

In Leishmania mexicana, the protease gp63 has been documented as the protein responsible for cyclooxygenase (COX) activity. The present work aimed to obtain a monoclonal antibody capable of recognizing this protein without blocking the COX-like enzymatic activity. The antibody produced by the selected hybridoma was named D12 mAb. The antigen recognized by the D12 mAb was characterized by the determination of COX activity associated with immune complexes in the presence of exogenous arachidonic acid (AA) using the commercial Activity Assay Abcam kit. LSM-SMS analysis validated the identity of the antigen associated with the D12 mAb as the L. mexicana protease gp63. Confocal microscopy assays with the D12 mAb detected, by cross-recognition, similar proteins in other protozoan parasites. COX-like molecules are located in vesicular structures, homogeneously distributed throughout the cytoplasm in amastigotes (intracellular infectious phase) and promastigotes of L. mexicana, and trophozoites of Entamoeba histolytica, Acanthamoeba castellanii, and Naegleria fowleri. However, in Giardia duodenalis trophozoites, the distribution of the COX-like molecule was also in perinuclear areas. In comparison, in Trypanosoma cruzi trypomastigotes, the distribution was mainly observed in the plasma membrane. Structural analyses of COX-2-like antigens revealed continuous and discontinuous epitopes for B cells, which could be relevant in the cross-reaction of D12 mAb with the analyzed parasites. These results indicate that the D12 mAb against the L. mexicana gp63 also recognizes a COX-like molecule in several protozoan parasites, suggesting that this D12 mAb could potentially be used in combined therapies against infectious diseases.

Effect of Oral Intake of Carrot Juice on Cyclooxygenases and Cytokines in Healthy Human Blood Stimulated by Lipopolysaccharide

In vitro studies and animal studies have shown that chemical compounds contained in carrots, such as falcarinol and falcarindiol, can prevent inflammation. The present study was designed to test whether the oral intake of carrot juice containing falcarinol and falcarindiol affects the activity of cyclooxygenase (COX) enzymes and the secretion of inflammatory cytokines in human blood. Carrot juice (500 mL) was administered orally to healthy volunteers, and blood samples were drawn before and 1 h after juice intake at the time point when peak concentrations of falcarinol and falcariondiol have been shown in the blood. The blood samples were divided, and one sample was allowed to coagulate for 1 h at room temperature before analyzing the synthesis of thromboxane B2 (TBX2) by the COX1 enzyme using an enzyme linked immunosorbent assay (ELISA). The other blood samples were stimulated ex vivo with lipopolysaccharide and incubated at 37 °C for 24 h. The ELISA and cytokine multiplex analysis assessed the levels of COX-2-induced prostaglandin E2 (PGE2) and inflammatory markers interleukin (IL) 1α, IL1β, IL6, IL16, and tumor necrosis factor α (TNFα). Inflammatory cytokines such as IL1α and IL16 were significantly reduced in the LPS stimulated blood samples with higher concentrations of falcarinol and falcariondiol compared to the control samples taken before the intake of carrot juice. The levels of TBX2, PGE2, IL1β, IL6, and TNFα were not affected by the carrot juice intake blood samples not stimulated with LPS. In conclusion, carrot juice rich in the polyacetylens falcarinol and falcarindiol affects blood leukocytes, priming them to better cope with inflammatory conditions, evident by the reduced secretion of the proinflammatory cytokines IL1α and IL16.

N-Acetylcysteine Decreases Myocardial Content of Inflammatory Mediators Preventing the Development of Inflammation State and Oxidative Stress in Rats Subjected to a High-Fat Diet

Arachidonic acid (AA) is a key precursor for proinflammatory and anti-inflammatory derivatives that regulate the inflammatory response. The modulation of AA metabolism is a target for searching a therapeutic agent with potent anti-inflammatory action in cardiovascular disorders. Therefore, our study aims to determine the potential preventive impact of N-acetylcysteine (NAC) supplementation on myocardial inflammation and the occurrence of oxidative stress in obesity induced by high-fat feeding. The experiment was conducted for eight weeks on male Wistar rats fed a standard chow or a high-fat diet (HFD) with intragastric NAC supplementation. The Gas-Liquid Chromatography (GLC) method was used to quantify the plasma and myocardial AA levels in the selected lipid fraction. The expression of proteins included in the inflammation pathway was measured by the Western blot technique. The concentrations of arachidonic acid derivatives, cytokines and chemokines, and oxidative stress parameters were determined by the ELISA, colorimetric, and multiplex immunoassay kits. We established that in the left ventricle tissue NAC reduced AA concentration, especially in the phospholipid fraction. NAC administration ameliorated the COX-2 and 5-LOX expression, leading to a decrease in the PGE2 and LTC4 contents, respectively, and augmented the 12/15-LOX expression, increasing the LXA4 content. In obese rats, NAC ameliorated NF-κB expression, inhibiting the secretion of proinflammatory cytokines. NAC also affected the antioxidant levels in HFD rats through an increase in GSH and CAT contents with a simultaneous decrease in the levels of 4-HNE and MDA. We concluded that NAC treatment weakens the NF-κB signaling pathway, limiting the development of myocardial low-grade inflammation, and increasing the antioxidant content that may protect against the development of oxidative stress in rats with obesity induced by an HFD.

Targeting inflammation: a potential approach for the treatment of depression

Major depressive disorder (MDD) or Depression is one of the serious neuropsychiatric disorders affecting over 280 million people worldwide. It is 4th important cause of disability, poor quality of life, and economic burden. Women are more affected with the depression as compared to men and severe depression can lead to suicide. Most of the antidepressants predominantly work through the modulation on the availability of monoaminergic neurotransmitter (NTs) levels in the synapse. Current antidepressants have limited efficacy and tolerability. Moreover, treatment resistant depression (TRD) is one of the main causes for failure of standard marketed antidepressants. Recently, inflammation has also emerged as a crucial factor in pathological progression of depression. Proinflammatory cytokine levels are increased in depressive patients. Antidepressant treatment may attenuate depression via modulation of pathways of inflammation, transformation in structure of brain, and synaptic plasticity. Hence, targeting inflammation may be emerged as an effective approach for the treatment of depression. The present review article will focus on the preclinical and clinical studies that targets inflammation. In addition, it also concentrates on the therapeutic approaches' that targets depression via influence on the inflammatory signaling pathways. Graphical abstract demonstrate the role of various factors in the progression and neuroinflammation, oxidative stress. It also exhibits the association of neuroinflammation, oxidative stress with depression.

Whole-Body PET Imaging in Humans Shows That 11C-PS13 Is Selective for Cyclooxygenase-1 and Can Measure the In Vivo Potency of Nonsteroidal Antiinflammatory Drugs

Both cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) convert arachidonic acid to prostaglandin H₂, which has proinflammatory effects. The recently developed PET radioligand ¹¹C-PS13 has excellent in vivo selectivity for COX-1 over COX-2 in nonhuman primates. This study sought to evaluate the selectivity of ¹¹C-PS13 binding to COX-1 in humans and assess the utility of ¹¹C-PS13 to measure the in vivo potency of nonsteroidal antiinflammatory drugs. Methods: Baseline ¹¹C-PS13 whole-body PET scans were obtained for 26 healthy volunteers, followed by blocked scans with ketoprofen (n = 8), celecoxib (n = 8), or aspirin (n = 8). Ketoprofen is a highly potent and selective COX-1 inhibitor, celecoxib is a preferential COX-2 inhibitor, and aspirin is a selective COX-1 inhibitor with a distinct mechanism that irreversibly inhibits substrate binding. Because blood cells, including platelets and white blood cells, also contain COX-1, ¹¹C-PS13 uptake inhibition from blood cells was measured in vitro and ex vivo (i.e., using blood obtained during PET scanning). Results: High ¹¹C-PS13 uptake was observed in major organs with high COX-1 density, including the spleen, lungs, kidneys, and gastrointestinal tract. Ketoprofen (1-75 mg orally) blocked uptake in these organs far more effectively than did celecoxib (100-400 mg orally). On the basis of the plasma concentration to inhibit 50% of the maximum radioligand binding in the spleen (in vivo IC ₅₀), ketoprofen (<0.24 μM) was more than 10-fold more potent than celecoxib (>2.5 μM) as a COX-1 inhibitor, consistent with the in vitro potencies of these drugs for inhibiting COX-1. Blockade of ¹¹C-PS13 uptake from blood cells acquired during the PET scans mirrored that in organs of the body. Aspirin (972-1,950 mg orally) blocked such a small percentage of uptake that its in vivo IC ₅₀ could not be determined. Conclusion: ¹¹C-PS13 selectively binds to COX-1 in humans and can measure the in vivo potency of nonsteroidal antiinflammatory drugs that competitively inhibit arachidonic acid binding to COX-1. These in vivo studies, which reflect the net effect of drug absorption and metabolism in all organs of the body, demonstrated that ketoprofen had unexpectedly high potency, that celecoxib substantially inhibited COX-1, and that aspirin acetylation of COX-1 did not block binding of the representative nonsteroidal inhibitor ¹¹C-PS13.

Environmental exposure to non-steroidal anti-inflammatory drugs and potential contribution to eggshell thinning in birds

Abnormally thin eggshells can reduce avian reproductive success, and have caused rapid population declines. The best known examples of this phenomenon are the widespread population crashes in birds, mostly raptors, fish eating birds, and scavengers, caused by the pesticide DDT and its isomers in the 1960s. A variety of other chemicals have been reported to cause eggshell thinning. Non-steroidal anti-inflammatory drugs (NSAIDs), which are extensively and increasingly used in human and veterinary medicine, may be one particularly concerning group of chemicals that demonstrate an ability to impair eggshell development, based both on laboratory studies and on their known mechanism of action. In this review, we outline environmental and wildlife exposure to NSAIDs, describe the process of eggshell formation, and discuss pathways affected by NSAIDs. We list pharmaceuticals, including NSAIDs, and other compounds demonstrated to reduce eggshell thickness, and highlight their main mechanisms of action. Dosing studies empirically demonstrated that NSAIDs reduce eggshell thickness through cyclooxygenase inhibition, which suppresses prostaglandin synthesis and reduces the calcium available for the mineralization of eggshell. Using the US EPA's CompTox Chemicals Dashboard, we show that NSAIDs are predicted to strongly inhibit cyclooxygenases. NSAIDs have been observed both in the putative diet of scavenging birds, and we report examples of NSAIDs detected in eggs or tissues of wild and captive Old World vultures. We suggest that NSAIDs in the environment represent a hazard that could impair reproduction in wild birds.

The octadecanoids: an emerging class of lipid mediators

Oxylipins are enzymatic and non-enzymatic metabolites of mono- or polyunsaturated fatty acids that encompass potent lipid mediators including the eicosanoids and docosanoids. Previously considered of low interest and often dismissed as 'just fat', octadecanoid oxylipins have only recently begun to be recognized as lipid mediators in humans. In the last few years, these compounds have been found to be involved in the mediation of multiple biological processes related to nociception, tissue modulation, cell proliferation, metabolic regulation, inflammation, and immune regulation. At the same time, the study of octadecanoids is hampered by a lack of standardization in the field, a paucity of analytical standards, and a lack of domain expertise. These issues have collectively limited the investigation of the biosynthesis and bioactivity of octadecanoids. Here, we present an overview of the primary enzymatic pathways for the oxidative metabolism of 18-carbon fatty acids in humans and of the current knowledge of the major biological activity of the resulting octadecanoids. We also propose a systematic nomenclature system based upon that used for the eicosanoids in order to avoid ambiguities and resolve multiple designations for the same octadecanoid. The aim of this review is to provide an initial framework for the field and to assist in its standardization as well as to increase awareness of this class of compounds in order to stimulate research into this interesting group of lipid mediators.

Molecular docking studies and biological evaluation of isoxazole-carboxamide derivatives as COX inhibitors and antimicrobial agents

Non-steroidal anti-inflammatory drugs (NSAIDs) are considered one of the most commonly used medications globally. Seventeen isoxazole-containing compounds with various functional groups were evaluated in this work to identify which one was the most potent and which group was most selective toward COX-1 and COX-2 by using an in vitro COX inhibition assay kit. Their cytotoxicity was evaluated on the normal hepatic cell line (LX-2) utilizing the MTS assay. Moreover, these molecules' antibacterial and antifungal activities were evaluated using a microdilution assay against several bacterial and fungal species. In addition, molecular docking studies were conducted to identify the possible binding interactions between these compounds and their biological targets by using the X-ray crystal structure of the human COX enzyme and different proteins of bacterial and fungal strains. At the same time, the QiKProp module was used for ADME-T analysis. The results showed that all evaluated isoxazole derivatives showed moderate to potent activities against COX enzymes. The most potent compound against COX-1 and COX-2 enzymes was A13, with IC50 values of 64 and 13 nM, respectively, and a significant selectivity ratio of 4.63. It was clear that the 3,4-dimethoxy substitution on the first phenyl ring and the Cl atom on the other phenyl pushed the 5-methyl-isoxazole ring toward the secondary binding pocket and created the ideal binding interactions with the COX-2 enzyme in comparison with the other compounds. Compound A8 showed antibacterial and antifungal activities against Pseudomonas aeruginosa, Klebsiella pneumonia, and Candida albicans with MIC values of 2 mg/ml. In fact, this compound showed possible binding interactions with the elastase in P. aeruginosa and KPC-2 carbapenemase in K. pneumonia. Furthermore, for better understanding, molecular dynamics simulations were undertaken to study the change in dynamicity of the protein backbone and ligand after the ligand binds to the protein and to ensure the stability of ligand-protein complexes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-022-03408-8.

Anti-Inflammatory Activity of Olive Oil Polyphenols-The Role of Oleacein and Its Metabolites

The anti-inflammatory potential of oleacein, the main polyphenolic compound found in olive oil, and its main metabolites were characterized by their effects on RAW 264.7 macrophages challenged with lipopolysaccharide (LPS), and by their ability to inhibit enzymes of the arachidonic acid metabolism with a key role in the synthesis of pro-inflammatory lipid mediators. Oleacein at 12.5 µM significantly decreased the amount of L-citrulline and ^●NO generated by LPS-stimulated macrophages. Hydroxytyrosol, hydroxytyrosol acetate and hydroxytyrosol acetate sulfate were also able to reduce the cellular amount of ^●NO, although to a lesser extent. In contrast, hydroxytyrosol glucuronide and sulfate did not show detectable effects. Oleacein was also able to inhibit the coupled PLA₂ + 5-LOX enzyme system (IC₅₀ = 16.11 µM), as well as the 5-LOX enzyme (IC₅₀ = 45.02 µM). Although with lower activity, both hydroxytyrosol and hydroxytyrosol acetate were also capable of inhibiting these enzymes at a concentration of 100 µM. None of the other tested metabolites showed a capacity to inhibit these enzymes. In contrast, all compounds, including glucuronides and sulfate metabolites, showed a remarkable capacity to inhibit both cyclooxygenase isoforms, COX-1 and COX-2, with IC₅₀ values lower than 3 µM. Therefore, oleacein and its metabolites have the ability to modulate ^●NO- and arachidonic acid-dependent inflammatory cascades, contributing to the anti-inflammatory activity associated with olive oil polyphenols.

COX/iNOS dependence for angiotensin-II-induced endothelial dysfunction

Vascular dysfunction induced by angiotensin-II can result from direct effects on vascular and inflammatory cells and indirect hemodynamic effects. Using isolated and functional cultured aortas, we aimed to identify the effects of angiotensin-II on cyclooxygenase (COX) and inducible nitric oxide synthase (iNOS) and evaluate their impact on vascular reactivity. Aortic rings from mice were incubated overnight in culture medium containing angiotensin-II (100 nmol/L) or vehicle to induce vascular disfunction. Vascular reactivity of cultured arteries was evaluated in a bath chamber. Immunofluorescence staining for COX-1 and COX-2 was performed. Nitric oxide (NO) formation was approached by the levels of nitrite, a NO end product, and using a fluorescent probe (DAF). Oxidative and nitrosative stress were determined by DHE fluorescence and nitrotyrosine staining, respectively. Arteries cultured with angiotensin-II showed impairment of endothelium-dependent relaxation, which was reversed by the AT₁ receptor antagonist. Inhibition of COX and iNOS restored vascular relaxation, suggesting a common pathway in which angiotensin-II triggers COX and iNOS, leading to vasoconstrictor receptors activation. Moreover, using selective antagonists, TP and EP were identified as the receptors involved in this response. Endothelium-dependent contractions of angiotensin-II-cultured aortas were blunted by ibuprofen, and increased COX-2 immunostaining was found in the arteries, indicating endothelium release of vasoconstrictor prostanoids. Angiotensin-II induced increased reactive oxygen species and NO production. An iNOS inhibitor prevented NO enhancement and nitrotyrosine accumulation in arteries stimulated with angiotensin-II. These results confirm that angiotensin-II causes vascular inflammation that culminates in endothelial dysfunction in an iNOS and COX codependent manner.

Bothrops moojeni snake venom induces an inflammatory response in preadipocytes: Insights into a new aspect of envenomation

Bothrops envenomation is a public health problem in Brazil. Despite the advances in the knowledge of the pathogenesis of systemic and local effects induced by Bothrops venom, the target tissues to this venom are not completely characterised. As preadipocytes are important cells of the adipose tissue and synthesize inflammatory mediators, we investigated the ability of B. moojeni snake venom (Bmv) to stimulate an inflammatory response in 3T3-L1 preadipocytes in vitro, focusing on (1) the release of PGE2, IL-6, TNF-α, MCP-1, KC, leptin and adiponectin; (2) the mechanisms involved in PGE2 release and (3) differentiation of these cells. Cytotoxicity of Bmv was determined by MTT assay. The concentrations of PGE2, cytokines and adipokines were quantified by EIA. Participation of the COX-1 and COX-2 enzymes, NF-κB and PGE2 receptors (EP1-4) was assessed using a pharmacological approach, and protein expression of the COX enzymes and P-NF-κB was analysed by western blotting. Preadipocyte differentiation was quantified by Oil Red O staining. Bmv (1 μg/mL) induced release of PGE2, IL-6 and KC and increased expression of COX-2 in preadipocytes. Basal levels of TNF-α, MCP-1, leptin and adiponectin were not modified. Treatment of cells with SC560 (COX-1 inhibitor) and NS398 (COX-2 inhibitor) inhibited Bmv-induced PGE2 release. Bmv induced phosphorylation of NF-κB, and treatment of the cells with TPCK and SN50, which inhibit distinct NF-κB domains, significantly reduced Bmv-induced PGE2 release, as did the treatment with an antagonist of PGE2 receptor EP1, unlike treatment with antagonists of EP2, EP3 or EP4. Bmv also induced lipid accumulation in differentiating cells. These results demonstrate that Bmv can activate an inflammatory response in preadipocytes by inducing the release of inflammatory mediators; that PGE2 production is mediated by the COX-1, COX-2 and NF-κB pathways; and that engagement of EP1 potentiates PGE2 synthesis via a positive feedback mechanism. Our findings highlight the role of the adipose tissue as another target for Bmv and suggest that it contributes to Bothrops envenomation by producing inflammatory mediators.

Comparison of Absolute Expression and Turnover Number of COX-1 and COX-2 in Human and Rodent Cells and Tissues

Objective

We aim to quantify the absolute protein expression of cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) in various cells and tissues to determine the relative contribution of COX-1 and COX-2 to PGE₂ production.

Methods

An LC-MS method was developed and validated, then used for quantifying the absolute amounts of COX-1 and COX-2 in recombinant human COX-1 and COX-2, lysates from different cells, tissue microsomes of rodents and humans, Pirc rat colonic polyps, and biopsy specimens from squamous cell carcinoma (SCC) patients. The COX-1 and COX-2 turnover numbers were subsequently calculated based on apparent formation rates of PGE₂.

Results

A robust LC-MS method for quantification of COX-1 and COX-2 was developed and validated and then used to calculate their apparent turnover numbers. The results showed that COX-1 expression levels were much higher than that of COX-2 in all the tested tissues including the colonic epithelium of F344 (28-fold) and Pirc rats (20-fold), colonic polyps of Pirc rats (8-fold), and biopsy specimens of SCC patients (11–17-fold). In addition, both COX-1 and COX-2 were higher in polyps when compared to adjacent mucosa of Pirc rats. The turnover number of recombinant human COX-2 was 14-fold higher than that of recombinant human COX-1. LPS stimulation increased COX-2 protein expression in three cell lines (Raw 264.7, SCC9 and EOMA) as expected but unexpectedly increased COX-1 protein expression (13.8-fold) in EOMA cells.

Conclusion

In human oral cancer tissues and cells as well as Pirc rat colon, COX-1 plays an unexpectedly but more important role than COX-2 in abnormal PGE₂ production since COX-1 expression is much higher than COX-2. In addition, COX-1 expression levels are inducible in cells, and higher in polyps than surrounding mucosa in Pirc rat colon. These results indicate that targeted suppression of local COX-1 should be considered to reduce colon-specific PGE₂-mediated inflammation.

Aspirin sensitivity of PIK3CA-mutated Colorectal Cancer: potential mechanisms revisited

PIK3CA mutations are amongst the most prevalent somatic mutations in cancer and are associated with resistance to first-line treatment along with low survival rates in a variety of malignancies. There is evidence that patients carrying PIK3CA mutations may benefit from treatment with acetylsalicylic acid, commonly known as aspirin, particularly in the setting of colorectal cancer. In this regard, it has been clarified that Class IA Phosphatidylinositol 3-kinases (PI3K), whose catalytic subunit p110α is encoded by the PIK3CA gene, are involved in signal transduction that regulates cell cycle, cell growth, and metabolism and, if disturbed, induces carcinogenic effects. Although PI3K is associated with pro-inflammatory cyclooxygenase-2 (COX-2) expression and signaling, and COX-2 is among the best-studied targets of aspirin, the mechanisms behind this clinically relevant phenomenon are still unclear. Indeed, there is further evidence that the protective, anti-carcinogenic effect of aspirin in this setting may be mediated in a COX-independent manner. However, until now the understanding of aspirin's prostaglandin-independent mode of action is poor. This review will provide an overview of the current literature on this topic and aims to analyze possible mechanisms and targets behind the aspirin sensitivity of PIK3CA-mutated cancers.

Neurobehavioral Toxicity Induced by Carbendazim in Rats and the Role of iNOS, Cox-2, and NF-κB Signalling Pathway

Carbendazim (CBZ) is one of the most common fungicides used to fight plant fungal diseases, otherwise, it leaves residue on fruits, vegetables, and soil that contaminate the environment, water, animal, and human causing serious health problems. Several studies have reported the reproductive and endocrine pathological disorders induced by CBZ in several animal models, but little is known about its neurotoxicity. So that, the present study aimed to explain the possible mechanisms of CBZ induced neurotoxicity in rats. Sixty male Wistar rats were divided into 4 groups (n = 15). Group (1) received normal saline and was kept as the negative control group, whereas groups (2, 3, 4) received CBZ at 100, 300, 600 mg/kg b.wt respectively. All rats received the aforementioned materials daily via oral gavage. Brain tissue samples were collected at 7, 14, 28 days from the beginning of the experiment. CBZ induced oxidative stress damage manifested by increasing MDA levels and reducing the levels of TAC, GSH, CAT in some brain areas at 14 and 28 days. There were extensive neuropathological alterations in the cerebrum, hippocampus, and cerebellum with strong caspase-3, iNOS, Cox-2 protein expressions mainly in rats receiving 600 mg/kg CBZ at each time point. Moreover, upregulation of mRNA levels of NF-κB, TNF-α, IL-1B genes and downregulation of the transcript levels of both AchE and MAO genes were recorded in all CBZ receiving groups at 14 and 28 days especially those receiving 600 mg/kg CBZ. Our results concluded that CBZ induced dose- and time-dependent neurotoxicity via disturbance of oxidant/antioxidant balance and activation of NF-κB signaling pathway. We recommend reducing the uses of CBZ in agricultural and veterinary fields or finding other novel formulations to reduce its toxicity on non-target organisms and enhance its efficacy on the target organisms.

Associations of Prior Chronic Use of Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) and Glucocorticoids With Cachexia Incidence and Survival

Background

Cachexia is an inflammatory and metabolic syndrome of unintentional weight loss through depletion of muscle and adipose tissue. There is limited knowledge of how chronic use of non-steroidal anti-inflammatory drugs (NSAIDs) and glucocorticoids affect cachexia development. The purpose of this study was to investigate associations between prior long-term use of NSAIDs or glucocorticoids with cachexia incidence and post-diagnosis weight loss progression in a retrospective cancer patient cohort.

Methods

Of 3,802 lung or gastrointestinal cancer patient records, 3,180 comprised our final cohort. Patient demographic information, tumor qualities, medication histories, and comorbidities were assessed. Cachexia was defined as having developed prior to oncologic treatment. Statistical evaluations included categorical, multivariate logistic regression, and log-rank survival analyses. Development of substantial post-diagnosis weight loss was calculated and interpreted for patients without cachexia at diagnosis.

Results

Chronic prior use of any NSAID or glucocorticoid medication was associated with approximate absolute and relative reductions in cachexia incidence at diagnosis of 10 and 25 percent (P<0.0001). In multivariate analyses, NSAID medications demonstrated a 23 percent reduction in cachexia incidence likelihood (OR=0.770; 95% CI=0.594, 0.998; P=0.0481). Patients without cachexia at diagnosis were significantly more likely to develop substantial post-diagnosis weight loss from pre-diagnosis use groups of glucocorticoids (OR= 1.452; 95% CI=1.065, 1.979; P=0.0183) or NSAIDs (OR=1.411; 95% CI=1.082, 1.840; P=0.011).

Conclusions

Our findings suggest a protective effect of prior anti-inflammatory medications, primarily NSAIDs, against manifestations of the cachexia phenotype at cancer diagnosis. These observations support further exploration of potential therapeutic benefits from anti-inflammatory medications early in cancer management.