Cyclooxygenase-independent actions of cyclooxygenase inhibitors

NF-κB Signaling Pathway in Rheumatoid Arthritis: Mechanisms and Therapeutic Potential

Rheumatoid arthritis (RA) is an autoimmune chronic inflammatory disease that imposes a heavy economic burden on patients and society. Bone and cartilage destruction is considered an important factor leading to RA, and inflammation, oxidative stress, and mitochondrial dysfunction are closely related to bone erosion and cartilage destruction in RA. Currently, there are limitations in the clinical treatment methods for RA, which urgently necessitates finding new effective treatments for patients. Nuclear transcription factor-κB (NF-κB) is a signaling transcription factor that is widely present in various cells. It plays an important role as a stress source in the cellular environment and regulates gene expression in processes such as immunity, inflammation, cell proliferation, and apoptosis. NF-κB has long been recognized as a pathogenic factor of RA, and its activation can exacerbate RA by promoting inflammation, oxidative stress, mitochondrial dysfunction, and bone destruction. Conversely, inhibiting the activity of the NF-κB pathway effectively inhibits these pathological processes, thereby alleviating RA. Therefore, NF-κB may be a potential therapeutic target for RA. This article describes the physiological structure of NF-κB and its important role in RA through the regulation of oxidative stress, inflammatory response, mitochondrial function, and bone destruction. Meanwhile, we also summarized the impact of NF-κB crosstalk with other signaling pathways on RA and the effect of related drugs or inhibitors targeting NF-κB on RA. The purpose of this article is to provide evidence for the role of NF-κB in RA and to emphasize its significant role in RA by elucidating the mechanisms, so as to provide a theoretical basis for targeting the NF-κB pathway as a treatment for RA.

The Association Between Chronic Aspirin Treatment and the Clinical Course and Outcomes of Acute Pancreatitis

BACKGROUND AND AIM

Animal model studies have shown that pretreatment with the anti-inflammatory drug Aspirin had a positive effect on acute pancreatitis outcomes. The impact of Aspirin on acute pancreatitis outcomes in humans is unknown. We aimed to determine the association between chronic Aspirin treatment and the clinical course and outcomes of acute pancreatitis in a large cohort.

MATERIALS AND METHODS

This retrospective single-center observational study included all adult patients admitted with a primary diagnosis of acute pancreatitis between January 2008 and June 2021. Patients were divided into 2 groups: chronic Aspirin treatment group and non-Aspirin treatment group. The differences in baseline comorbidities were adjusted for by propensity score matching.

RESULTS

The study included 2308 patients, of whom 596 (25.8%) were chronically treated with Aspirin. Overall, chronic Aspirin treatment was associated with increased 30-day mortality with an odds ratio (OR) of 1.91 (95% confidence interval [CI], 1.21-2.97; P = 0.005). It was also associated with severe pancreatitis (OR, 2.61; 95% CI, 2.00-3.39; P < 0.001). In the propensity matched cohort, 30-day mortality rates (OR, 0.53; 95% CI, 0.20-1.31; P = 0.2) and severe pancreatitis rates (OR, 1.2; 95% CI, 0.83-1.75; P = 0.3) were similar between the two groups.

CONCLUSIONS

Among patients with acute pancreatitis, chronic Aspirin treatment was not associated with decreased disease severity or reduced 30-day mortality rate.

Understanding the selectivity of nonsteroidal anti-inflammatory drugs for cyclooxygenases using quantum crystallography and electrostatic interaction energy

Quantum crystallography methods have been employed to investigate complex formation between nonsteroidal anti-inflammatory drugs (NSAIDs) and cyclooxygenase (COX) enzymes, with particular focus on the COX-1 and COX-2 isoforms. This study analyzed the electrostatic interaction energies of selected NSAIDs (flurbiprofen, ibuprofen, meloxicam and celecoxib) with the active sites of COX-1 and COX-2, revealing significant differences in binding profiles. Flurbiprofen exhibited the strongest interactions with both COX-1 and COX-2, indicating its potent binding affinity. Celecoxib and meloxicam showed a preference for COX-2, consistent with their known selectivity for this isoform, while ibuprofen showed comparable interaction energies with both isoforms, reflecting its nonselective inhibition pattern. Key amino-acid residues, including Arg120, Arg/His513 and Tyr355, were identified as critical determinants of NSAID selectivity and binding affinity. The findings highlight the complex interplay between interaction energy and selectivity, suggesting that while electrostatic interactions play a fundamental role, additional factors such as enzyme dynamics and the hydrophobic effect also contribute to the therapeutic efficacy and safety profiles of NSAIDs. These insights provide valuable guidance for the rational design of NSAIDs with enhanced therapeutic benefits and minimized adverse effects.

Celecoxib and rofecoxib have different effects on small intestinal ischemia/reperfusion injury in rats

Introduction

Intestinal ischemia/reperfusion (I/R) injury is associated with high mortality and there is an unmet need for novel therapies. The intestinal expression of cyclooxygenase-2 (COX-2) increases rapidly after mesenteric I/R, but it is still a question of debate whether selective COX-2 inhibitors can mitigate I/R-induced gut injury. Here we aimed to compare the effect of celecoxib and rofecoxib, two selective COX-2 inhibitors, on intestinal I/R-induced injury in rats.

Methods

Wistar rats were treated with celecoxib (10 and 100 mg/kg), rofecoxib (5 and 50 mg/kg), or vehicle for 8 days via gavage and then were subjected to sham operation or mesenteric I/R. Small intestinal inflammation and tissue damage were assessed by histology and quantification of inflammatory and tight junction proteins. The intestinal activity of COX enzymes was determined by a COX activity assay.

Results

The higher dose of celecoxib reduced the I/R-associated increase in inflammatory mediators (myeloperoxidase, pentraxin 3, COX-2, interleukin-1β) and loss of tight junction proteins (claudin-1, occludin), whereas the lower dose of celecoxib was only marginally effective. However, even high-dose celecoxib failed to prevent the histological injury of the mucosa. In contrast to celecoxib, rofecoxib did not affect intestinal inflammation and injury at any of the tested doses. Neither celecoxib nor rofecoxib affected the I/R-induced changes of HO-1 and PPAR-γ, known off-targets of COX-inhibitors, but celecoxib increased the I/R-induced elevation of Bax/Bcl-2, a marker of apoptosis, whereas rofecoxib reduced the elevation of phospho-Akt. Importantly, high-dose celecoxib, but not rofecoxib, has already reduced intestinal COX-1 activity.

Conclusion

Our study provides evidence for the higher anti-inflammatory efficacy of celecoxib compared to rofecoxib in mesenteric I/R injury, which is likely due to its lower selectivity for COX-2. However, even high-dose celecoxib was unable to reduce the mucosal damage. Our results suggest that selective COX-2 inhibitors have only limited therapeutic value in intestinal I/R injury.

Regular Nonsteroidal Anti-Inflammatory Drug Use Increases Stress Fracture Risk in the General Population: A Retrospective Case-Control Study

Previous studies have shown that the use of nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with increased stress fracture risk. This phenomenon has been studied predominantly in high-activity individuals, so data regarding the general population are limited despite the substantial economic and resource burden of stress fracture injuries within the general US population. Furthermore, our preclinical studies demonstrate that regular use of NSAIDs also diminishes the intrinsic ability of bone to resist fracture. To determine the association of regular NSAID use with stress fractures in the general population, we surveyed subjects presenting with either stress fracture or uncomplicated ankle sprain to assess their use of NSAIDs over the three months before their injury. We hypothesized that subjects with stress fractures would have increased regular NSAID usage as compared to controls. Subjects diagnosed with a stress fracture (n = 56) and subjects with uncomplicated ankle sprains (n = 51; control) were surveyed about their NSAID use at the time of their diagnosis and in the previous three months using a questionnaire based on the National Health and Nutrition Examination Survey (NHANES). Subjects were surveyed in person on the day of their injury diagnosis or by phone within 30 days of their diagnosis. Fisher's exact test was used to determine significant differences in NSAID usage between stress fracture and control subjects. Subjects diagnosed with stress fractures had a statistically significant increase in both current use (p=0.03) and regular use (p=0.04) of ibuprofen/naproxen/celecoxib as compared to control subjects. There were no significant differences in the use of aspirin, acetaminophen, or prescription medications containing acetaminophen between groups. Consistent with previous clinical reports, we observed a strong correlation between regular ibuprofen/naproxen/celecoxib use and stress fracture incidence in the general population. These results indicate that patients at high risk of stress fracture should avoid regular use of ibuprofen, naproxen, or celecoxib.

Research progress on nonsteroidal anti-inflammatory drugs in the treatment of pituitary neuroendocrine tumors

Pituitary neuroendocrine tumor is the third most common primary intracranial tumor. Its main clinical manifestations include abnormal hormone secretion symptoms, symptoms caused by tumor compression of the surrounding pituitary tissue, pituitary stroke, and other anterior pituitary dysfunction. Its pathogenesis is yet to be fully understood. Surgical treatment is still the main treatment. Despite complete resection, 10%-20% of tumors may recur. While dopamine agonists are effective in over 90% of prolactinomas, prolonged use and individual variations can lead to increased drug resistance and a gradual decline in efficacy, which ultimately requires surgical intervention. Nonsteroidal anti-inflammatory drugs reduce the production of inflammatory mediator prostaglandins by inhibiting the activity of cyclooxygenase and exert antipyretic, analgesic, antiplatelet, and anti-inflammatory effects. In recent years, many in-depth studies have confirmed the potential of nonsteroidal anti-inflammatory drugs as a preventive and antitumor agent. It has been extensively utilized in the prevention and treatment of various types of cancer. However, their specific mechanisms of action still need to be fully elucidated. This article summarizes recent research progress on the expression of cyclooxygenase in pituitary neuroendocrine tumors and the treatment of nonsteroidal anti-inflammatory drugs. It provides a feasible theoretical basis for further research on pituitary neuroendocrine tumors and explores potential therapeutic targets.

NSAID use in orthopedic surgery: A review of current evidence and clinical practice guidelines

Nonsteroidal anti-inflammatory drugs (NSAIDs) are a valuable class of medications for orthopedic surgeons and often play a pivotal role in pain control. However, there are many common stipulations resulting in avoidance of its use in the treatment of musculoskeletal disease. This review summarizes the mechanism of action of NSAIDs as well as provides an overview of commonly used NSAIDs and the differences between them. It provides a concise summary on the osseous effects of NSAIDs with regard to bone healing and heterotopic ossification. Most of all, it serves as a guide or reference for orthopedic providers when counseling patients on the risks and benefits of NSAID use, as it addresses the common stipulations encountered: "It irritates my stomach," "I have a history of bariatric surgery," "I'm already on a blood thinner," "I've had a heart attack," and "I've got kidney problems" and synthesizes both current research and society recommendations regarding safe use and avoidance of NSAIDs.

Crystallization from solution versus mechanochemistry to obtain double-drug multicomponent crystals of ethacridine with salicylic/acetylsalicylic acids

Salicylic and acetylsalicylic acids and ethacridine have complementary bioactive properties. They can be combined to obtain double-drug multicomponent crystals. Their reactivity in different environments was explored to obtain the possible compounds, stable at different hydration degrees. Solution, liquid-assisted grinding, and dry preparation approaches were applied to the couples of reactants in different stoichiometric ratios. Four compounds were obtained, and three out of them were stable and reproducible enough to determine their structures using SCXRD or PXRD methods. When coupled to ethacridine, salicylic acid gave two stable structures (1 and 3, both showing 1:1 ratio but different hydration degree) and a metastable one (5), while acetylsalicylic acid only one structure from solution (2 in 1:1 ratio), while LAG caused hydrolysis and formation of the same compound obtained by LAG of ethacridine with salicylic acid. While solution precipitation gave dihydrated (1) or monohydrated (2) structures with low yields, LAG of salicylic acid and ethacridine allowed obtaining an anhydrous salt complex (3) with a yield close to 1. The structures obtained by solution crystallizations maximize π(acridine)-π(acridine) contacts with a less compact packing, while the LAG structure is more compact with a packing driven by hydrogen bonds. For all compounds, NMR, ATR-FTIR, and Hirshfeld surface analysis and energy framework calculations were performed.

Systemic Diclofenac Sodium Reduces Postoperative rhBMP-2 Induced Neuroinflammation: A Rodent Model Study

STUDY DESIGN

This is a basic science, animal research study.

OBJECTIVE

This study aims to explore, in rodent models, the effectiveness of systemic nonsteroidal anti-inflammatory drugs in reducing recombinant human bone morphogenetic protein-2 (rhBMP-2) induced neuroinflammation.

SUMMARY OF BACKGROUND DATA

rhBMP-2 is increasingly used to augment fusion in lumbar interbody fusion surgeries, although it can cause complications including postoperative radiculitis.

MATERIALS AND METHODS

Eighteen 8-week-old Sprague-Dawley rats underwent Hargreaves testing to measure the baseline thermal withdrawal threshold before undergoing surgical intervention. The L5 nerve root was exposed and wrapped with an Absorbable Collagen Sponge containing rhBMP-2. Rats were randomized into 3 groups: (1) Low dose (LD), (2) high dose (HD) diclofenac sodium, and (3) saline, receiving daily injection treatment. Hargreaves testing was performed postoperatively on days 5 and 7. Seroma volumes were measured by aspiration and the nerve root was then harvested for hematoxylin and eosin, immunohistochemistry, Luxol Fast Blue staining, and real-time quantitative polymerase chain reaction. The Student t test was used to evaluate the statistical significance among groups.

RESULTS

The intervention groups showed reduced seroma volume, and a general reduction of inflammatory markers (MMP12, MAPK6, GFAP, CD68, and IL18) compared with controls, with the reduction in MMP12 being statistically significant ( P = 0.02). Hematoxylin and eosin and immunohistochemistry of the nerve roots showed the highest macrophage density in the saline controls and the lowest in the HD group. Luxol Fast Blue staining showed the greatest extent of demyelination in the LD and saline groups. Lastly, Hargreaves testing, a functional measure of neuroinflammation, of the HD group demonstrated a minimal change in thermal withdrawal latency. In contrast, the thermal withdrawal latency of the LD and saline groups showed a statistically significant decrease of 35.2% and 28.0%, respectively ( P < 0.05).

CONCLUSION

This is the first proof-of-concept study indicating that diclofenac sodium is effective in alleviating rhBMP-2-induced neuroinflammation. This can potentially impact the clinical management of rhBMP-2-induced radiculitis. It also presents a viable rodent model for evaluating the effectiveness of analgesics in reducing rhBMP-2-induced inflammation.

Indomethacin Induces Spermidine/Spermine-N1-Acetyltransferase-1 via the Nucleolin-CDK1 Axis and Synergizes with the Polyamine Oxidase Inhibitor Methoctramine in Lung Cancer Cells

Indomethacin is a non-selective NSAID used against pain and inflammation. Although cyclooxygenase (COX) inhibition is considered indomethacin's primary action mechanism, COX-independent ways are associated with beneficial effects in cancer. In colon cancer cells, the activation of the peroxisome proliferator-activated receptor-γ (PPAR-γ) is related to the increase in spermidine/spermine-N1-acetyltransferase-1 (SSAT-1), a key enzyme for polyamine degradation, and related to cell cycle arrest. Indomethacin increases the SSAT-1 levels in lung cancer cells; however, the mechanism relying on the SSAT-1 increase is unclear. Thus, we asked for the influence of the PPAR-γ on the SSAT-1 expression in two lung cancer cell lines: H1299 and A549. We found that the inhibition of PPAR-γ with GW9662 did not revert the increase in SSAT-1 induced by indomethacin. Because the mRNA of SSAT-1 suffers a pre-translation retention step by nucleolin, a nucleolar protein, we explored the relationship between indomethacin and the upstream translation regulators of SSAT-1. We found that indomethacin decreases the nucleolin levels and the cyclin-dependent kinase 1 (CDK1) levels, which phosphorylates nucleolin in mitosis. Overexpression of nucleolin partially reverts the effect of indomethacin over cell viability and SSAT-1 levels. On the other hand, Casein Kinase, known for phosphorylating nucleolin during interphase, is not modified by indomethacin. SSAT-1 exerts its antiproliferative effect by acetylating polyamines, a process reverted by the polyamine oxidase (PAOX). Recently, methoctramine was described as the most specific inhibitor of PAOX. Thus, we asked if methoctramine could increase the effect of indomethacin. We found that, when combined, indomethacin and methoctramine have a synergistic effect against NSCLC cells in vitro. These results suggest that indomethacin increases the SSAT-1 levels by reducing the CDK1-nucleolin regulatory axis, and the PAOX inhibition with methoctramine could improve the antiproliferative effect of indomethacin.

Structural and Synthetic Aspects of Small Ring Oxa- and Aza-Heterocyclic Ring Systems as Antiviral Activities

Antiviral properties of different oxa- and aza-heterocycles are identified and properly correlated with their structural features and discussed in this review article. The primary objective is to explore the activity of such ring systems as antiviral agents, as well as their synthetic routes and biological significance. Eventually, the structure-activity relationship (SAR) of the heterocyclic compounds, along with their salient characteristics are exhibited to build a suitable platform for medicinal chemists and biotechnologists. The synergistic conclusions are extremely important for the introduction of a newer tool for the future drug discovery program.

Hypothesis: Efficacy of early treatments with some NSAIDs in COVID-19: Might it also depend on their direct and/or indirect zinc chelating ability?

The present work argues for the involvement of the zinc chelating ability of some non-steroidal anti-inflammatory drugs as an additive mechanism able to increase their efficacy against COVID-19.

Nonsteroidal anti-inflammatory drugs as antipyretics and modulators of a molecular clock(s) in the appendix of Sauromatum venosum inflorescence

The appendix of the Sauromatum senosum inflorescence is a striking example of thermogenesis in plants. On the day of opening, the Sauromatum appendix becomes hot, reaching up to 32 °C. Aspirin, salicylic acid and 2,6-dihydroxybenzoic acid, a subclass of NSAIDs, induce a temperature rise from three mitochondrial sources: alternative oxidase, F₁ F_O -ATP synthase and adenine nucleotide translocator. This temperature rise is synchronized and compounded under various light/dark regimes. We studied the effect of different subgroups of NSAIDs on the temperature rise. Tissue slices of appendix of Sauromatum and Arum italicum inflorescences at a pre-mature stage were treated with the three inducers in combination with one NSAID under constant light or darkness and under different photoperiods. Temperature rise generated by the three heat sources in the presence of inducers and different non-selective NSAIDs were not compounded and occurred at three different times. Under constant light, DuP-697, ibuprofen, flurbiprofen, acetaminophen and diclofenac suppressed the temperature rise induced by the three salicylates. Desynchronization and delayed temperature rise were detected with 6/42-h light/ dark and 15/33-h light/dark regimes in the presence of celecoxib and ibuprofen. With a 24/24-h light/dark regime, temperature rise was suppressed in the presence of ibuprofen. There were differences in response to individual NSAIDs between appendix tissue of A. italicum and S. venosum. Mitochondrial energy balance is affected by NSAIDs. There is an interaction between light/dark regime and temperature rise and a relationship between timing mechanism and temperature rise.

Influence of tramadol on bacterial burden in the standard neutropenic thigh infection model

The neutropenic thigh infection model is one of the standard models in pharmacokinetic/ pharmacodynamic (PK/PD) characterization of novel antibacterials which are urgently needed due to the rise of antimicrobial resistance. The model enables to investigate PK/PD parameters crucial for translation of animal results towards humans. However, the neutropenic thigh infection model can result in moderate to severe discomfort of the animals, especially when high inocula are used. Tramadol has been proven to reduce pain effectively. This study investigates if tramadol influences the bacterial burden in the primary organ, the thighs, and organs affected by secondary seeding. Therefore, several strains of the ESKAPE pathogens, namely S. aureus, P. aeruginosa, K. pneumoniae, E. coli, A. baumannii and E. faecalis were examined. It was shown that tramadol did not influence the bacterial burden neither in thighs nor in organs affected by secondary seeding for the strains of E. faecalis, S. aureus, P. aeruginosa, K. pneumoniae and E.coli tested here, whereas secondary seeding seemed to be affected by tramadol for the tested strain of A. baumannii. Consequently, it was demonstrated that tramadol is an option to reduce discomfort in the untreated group for the strains of five out of the six tested ESKAPE pathogens and, thereby, contributes to the refinement of one of the standard PK/PD models.

NSAIDs affect dendritic cell cytokine production

BACKGROUND

Immunotherapy is now considered as the new pillar in treatment of cancer patients. Dendritic cells (DCs) play an essential role in stimulating anti-tumor immune responses, as they are capable of cross-presenting exogenous tumor antigens in MHCI complexes to activate naïve CD8+ T cells. Analgesics, like non-steroid anti-inflammatory drugs (NSAIDs), are frequently given to cancer patients to help relieve pain, however little is known about their impact on DC function.

METHODS

Here, we investigated the effect of the NSAIDs diclofenac, ibuprofen and celecoxib on the three key processes of DCs required for proper CD8+ cytotoxic T cell induction: antigen cross-presentation, co-stimulatory marker expression, and cytokine production.

RESULTS

Our results show that TLR-induced pro- and anti-inflammatory cytokine excretion by human monocyte derived and murine bone-marrow derived DCs is diminished after NSAID exposure.

CONCLUSIONS

These results indicate that various NSAIDs can affect DC function and warrant further investigation into the impact of NSAIDs on DC priming of T cells and cancer immunotherapy efficacy.

Rivastigmine Reverses the Decrease in Synapsin and Memory Caused by Homocysteine: Is There Relation to Inflammation?

Elevated levels of homocysteine (Hcy) in the blood, called hyperhomocysteinemia (HHcy), is a prevalent risk factor for it has been shown that Hcy induces oxidative stress and increases microglial activation and neuroinflammation, as well as causes cognitive impairment, which have been linked to the neurodegenerative process. This study aimed to evaluate the effect of mild hyperhomocysteinemia with or without ibuprofen and rivastigmine treatments on the behavior and neurochemical parameters in male rats. The chronic mild HHcy model was chemically induced in Wistar rats by subcutaneous administration of Hcy (4055 mg/kg body weight) twice daily for 30 days. Ibuprofen (40 mg/kg) and rivastigmine (0.5 mg/kg) were administered intraperitoneally once daily. Motor damage (open field, balance beam, rotarod, and vertical pole test), cognitive deficits (Y-maze), neurochemical parameters (oxidative status/antioxidant enzymatic defenses, presynaptic protein synapsin 1, inflammatory profile parameters, calcium binding adapter molecule 1 (Iba1), iNOS gene expression), and cholinergic anti-inflammatory pathway were investigated. Results showed that mild HHcy caused cognitive deficits in working memory, and impaired motor coordination reduced the amount of synapsin 1 protein, altered the neuroinflammatory picture, and caused changes in the activity of catalase and acetylcholinesterase enzymes. Both rivastigmine and ibuprofen treatments were able to mitigate this damage caused by mild HHcy. Together, these neurochemical changes may be associated with the mechanisms by which Hcy has been linked to a risk factor for AD. Treatments with rivastigmine and ibuprofen can effectively reduce the damage caused by increased Hcy levels.

Treatment of Microcirculatory Disturbances in Acute Pancreatitis: Where Are We Now?

Acute pancreatitis is a serious inflammatory condition. Research has shown an increase in the number of pancreatitis-associated hospitalizations, with a marked decline in the mortality rates down to 0.79% in patients with acute pancreatitis and 0.26% in patients with exacerbation of chronic pancreatitis. Up to one-third of patients develop pancreatic tissue necrosis, with a mortality rate of 30%. One of the mechanisms is the disturbances in pancreatic microcirculation due to the release of endothelin, a long-acting vasoconstrictor. The development of pancreatitis causes the release of other inflammatory mediators, which reduce blood flow in the microcirculation. The activation of intracellular trypsinogen initiates a cascade of mechanisms in pancreatitis. There is no specific treatment for acute pancreatitis. Protease inhibitors are not effective in treating severe acute pancreatitis. There is an important role of low-molecular-weight heparin in attenuating necrosis and restoring perfusion of the pancreas. Other drugs used are endothelin receptor antagonists, antagonist of interleukin-1 and interleukin-6 receptors, α-tocopherol, tumor necrosis factor-α and platelet-activating factor inhibitors, acetylsalicylic acid, and local intra-arterial injection of lidocaine. The prophylactic use of antibiotics is not recommended. The treatment outcome of acute pancreatitis is still unsatisfactory.

Bidirectional Responses of Eight Neuroinflammation-Related Transcriptional Factors to 64 Flavonoids in Astrocytes with Transposable Insulated Signaling Pathway Reporters

Neuroinflammation is implicated in a variety of pathologies and is mechanistically linked to hyperactivation of glial cells in the central nervous system (CNS), predominantly in response to external stimuli. Multiple dietary factors were reported to alter neuroinflammation, but their actions on the relevant transcription factors in glia are not sufficiently understood. Here, an in vitro protocol employing cultured astroglial cells, which carry reporters of multiple signaling pathways associated with inflammation, was developed for screening environmental factors and synthetic drugs. Immortalized rat astrocyte line DI TNC1 was stably transfected with piggyBac transposon vectors containing a series of insulated reporters for the transcriptional activity of NF-κB, AP-1, signal transducer and activator of transcription 1 (STAT1), signal transducer and activator of transcription 3 (STAT3), aromatic hydrocarbon receptor (AhR), Nrf2, peroxisome proliferator-activated receptor γ (PPARγ), and HIF-1α, which is quantified via luciferase assay. Concatenated green fluorescent protein (GFP) expression was employed for simultaneous evaluation of cellular viability. Responses to a set of 64 natural and synthetic monomeric flavonoids representing six main structural classes (flavan-3-ols, flavanones, flavones, flavonols, isoflavones, and anthocyan(id)ins) were obtained at 10 and 50 μM concentrations. Except for HIF-1α, the activity of NF-κB and other transcription factors (TFs) in astrocytes was predominantly inhibited by flavan-3-ols and anthocyan(id)ins, while flavones and isoflavones generally activated these TFs. In addition, we obtained dose-response profiles for 11 flavonoids (apigenin, baicalein, catechin, cyanidin, epigallocatechin gallate, genistein, hesperetin, kaempferol, luteolin, naringenin, and quercetin) within the 1-100 μM range and in the presence of immune-stimulants and immune-suppressors. The flavonoid concentration profiles for TF-activation reveal biphasic response curves from the astrocytes. Apart from epigallocatechin gallate (EGCG), flavonoids failed to inhibit the NF-κB activation by proinflammatory agents [lipopolysaccharide (LPS), cytokines], but most of the tested polyphenols synergized with STAT3 inhibitors (stattic, ruxolitinib) against the activation of this TF in the astrocytes. We conclude that transposable insulated reporters of transcriptional activation represent a convenient neurochemistry tool in screening for activators/inhibitors of signaling pathways.

Inhibitors of Human 5-Lipoxygenase Potently Interfere With Prostaglandin Transport

5-Lipoxygenase (5-LO) is the key enzyme in the formation of pro-inflammatory leukotrienes (LT) which play an important role in a number of inflammatory diseases. Accordingly, 5-LO inhibitors are frequently used to study the role of 5-LO and LT in models of inflammation and cancer. Interestingly, the therapeutic efficacy of these inhibitors is highly variable. Here we show that the frequently used 5-LO inhibitors AA-861, BWA4C, C06, CJ-13,610 and the FDA approved compound zileuton as well as the pan-LO inhibitor nordihydroguaiaretic acid interfere with prostaglandin E₂ (PGE₂) release into the supernatants of cytokine-stimulated (TNFα/IL-1β) HeLa cervix carcinoma, A549 lung cancer as well as HCA-7 colon carcinoma cells with similar potencies compared to their LT inhibitory activities (IC₅₀ values ranging from 0.1–9.1 µM). In addition, AA-861, BWA4C, CJ-13,610 and zileuton concentration-dependently inhibited bacterial lipopolysaccharide triggered prostaglandin (PG) release into human whole blood. Western Blot analysis revealed that inhibition of expression of enzymes involved in PG synthesis was not part of the underlying mechanism. Also, liberation of arachidonic acid which is the substrate for PG synthesis as well as PGH₂ and PGE₂ formation were not impaired by the compounds. However, accumulation of intracellular PGE₂ was found in the inhibitor treated HeLa cells suggesting inhibition of PG export as major mechanism. Further, experiments showed that the PG exporter ATP-binding cassette transporter multidrug resistance protein 4 (MRP-4) is targeted by the inhibitors and may be involved in the 5-LO inhibitor-mediated PGE₂ inhibition. In conclusion, the pharmacological effects of a number of 5-LO inhibitors are compound-specific and involve the potent inhibition of PGE₂ export. Results from experimental models on the role of 5-LO in inflammation and pain using 5-LO inhibitors may be misleading and their use as pharmacological tools in experimental models has to be revisited. In addition, 5-LO inhibitors may serve as new scaffolds for the development of potent prostaglandin export inhibitors.

Sodium salicylate and 5-aminosalicylic acid synergistically inhibit the growth of human colon cancer cells and mouse intestinal polyp-derived cells

As colon cancer is one of the most common cancers in the world, practical prevention strategies for colon cancer are needed. Recently, treatment with aspirin and/or 5-aminosalicylic acid-related agents was reported to reduce the number of intestinal polyps in patients with familial adenomatous polyposis. To evaluate the mechanism of aspirin and 5-aminosalicylic acid for suppressing the colon polyp growth, single and combined effects of 5-aminosalicylic acid and sodium salicylate (metabolite of aspirin) were tested in the two human colon cancer cells with different cyclooxygenase-2 expression levels and intestinal polyp-derived cells from familial adenomatous polyposis model mouse. The combination induced cell-cycle arrest at the G1 phase along with inhibition of cell growth and colony-forming ability in these cells. The combination reduced cyclin D1 via proteasomal degradation and activated retinoblastoma protein. The combination inhibited the colony-forming ability of mouse colonic mucosa cells by about 50% and the colony-forming ability of mouse intestinal polyp-derived cells by about 90%. The expression level of cyclin D1 in colon mucosa cells was lower than that in intestinal polyp-derived cells. These results suggest that this combination may be more effective in inhibiting cell growth of intestinal polyps through cyclin D1 down-regulation.

NSAIDs Naproxen, Ibuprofen, Salicylate, and Aspirin Inhibit TRPM7 Channels by Cytosolic Acidification

Non-steroidal anti-inflammatory drugs (NSAIDs) are used for relieving pain and inflammation accompanying numerous disease states. The primary therapeutic mechanism of these widely used drugs is the inhibition of cyclooxygenase 1 and 2 (COX1, 2) enzymes that catalyze the conversion of arachidonic acid into prostaglandins. At higher doses, NSAIDs are used for prevention of certain types of cancer and as experimental treatments for Alzheimer’s disease. In the immune system, various NSAIDs have been reported to influence neutrophil function and lymphocyte proliferation, and affect ion channels and cellular calcium homeostasis. Transient receptor potential melastatin 7 (TRPM7) cation channels are highly expressed in T lymphocytes and are inhibited by Mg²⁺, acidic pH, and polyamines. Here, we report a novel effect of naproxen, ibuprofen, salicylate, and acetylsalicylate on TRPM7. At concentrations of 3–30mM, they reversibly inhibited TRPM7 channel currents. By measuring intracellular pH with the ratiometric indicator BCECF, we found that at 300μM to 30mM, these NSAIDs reversibly acidified the cytoplasm in a concentration-dependent manner, and propose that TRPM7 channel inhibition is a consequence of cytosolic acidification, rather than direct. NSAID inhibition of TRPM7 channels was slow, voltage-independent, and displayed use-dependence, increasing in potency upon repeated drug applications. The extent of channel inhibition by salicylate strongly depended on cellular PI(4,5)P₂ levels, as revealed when this phospholipid was depleted with voltage-sensitive lipid phosphatase (VSP). Salicylate inhibited heterologously expressed wildtype TRPM7 channels but not the S1107R variant, which is insensitive to cytosolic pH, Mg²⁺, and PI(4,5)P₂ depletion. NSAID-induced acidification was also observed in Schneider 2 cells from Drosophila, an organism that lacks orthologous COX genes, suggesting that this effect is unrelated to COX enzyme activity. A 24-h exposure to 300μM–10mM naproxen resulted in a concentration-dependent reduction in cell viability. In addition to TRPM7, the described NSAID effect would be expected to apply to other ion channels and transporters sensitive to intracellular pH.

Indomethacin, a non-steroidal anti-inflammatory drug, induces skin dryness via PPARγ in mice

Cyclooxygenase (COX)-1-selective inhibitors have side effects such as itching and dryness of the skin. In this study, the degree of skin dryness and the onset mechanism of this condition were investigated by comparing the effects of three non-steroidal anti-inflammatory drugs (NSAIDs) in mice. Mice were orally administered either indomethacin, loxoprofen sodium, or celecoxib (n = 5 per group) once daily for four consecutive days, and blood samples as well as skin and jejunal tissues were isolated on day 5. In the mice treated with indomethacin, transepidermal water loss was significantly increased, and dry skin was observed. In addition, the expression of matrix metalloproteinase (MMP)-I, mast cells, CD163, CD23, CD21, histamine, and peroxisome proliferation-activated receptor (PPAR)γ in the skin and jejunum was increased, and the blood levels of interleukin-10 and immunoglobulin E were also increased. In contrast, the expression of collagen type I in the skin was decreased. These results show that indomethacin activates PPARγ in the skin and jejunum, changes the polarity of macrophages, increases the secretion of MMP-1 from mast cells, and decomposes collagen type I, leading to dry skin.

A Glra3 phosphodeficient mouse mutant establishes the critical role of protein kinase A-dependent phosphorylation and inhibition of glycine receptors in spinal inflammatory hyperalgesia

ABSTRACT

Glycinergic neurons and glycine receptors (GlyRs) exert a critical control over spinal nociception. Prostaglandin E2 (PGE2), a key inflammatory mediator produced in the spinal cord in response to peripheral inflammation, inhibits a certain subtype of GlyRs (α3GlyR) that is defined by the inclusion of α3 subunits and distinctly expressed in the lamina II of the spinal dorsal horn, ie, at the site where most nociceptive nerve fibers terminate. Previous work has shown that the hyperalgesic effect of spinal PGE2 is lost in mice lacking α3GlyRs and suggested that this phenotype results from the prevention of PGE2-evoked protein kinase A (PKA)-dependent phosphorylation and inhibition of α3GlyRs. However, direct proof for a contribution of this phosphorylation event to inflammatory hyperalgesia was still lacking. To address this knowledge gap, a phospho-deficient mouse line was generated that carries a serine to alanine point mutation at a strong consensus site for PKA-dependent phosphorylation in the long intracellular loop of the GlyR α3 subunit. These mice showed unaltered spinal expression of GlyR α3 subunits. In behavioral experiments, they showed no alterations in baseline nociception, but were protected from the hyperalgesic effects of intrathecally injected PGE2 and exhibited markedly reduced inflammatory hyperalgesia. These behavioral phenotypes closely recapitulate those found previously in GlyR α3-deficient mice. Our results thus firmly establish the crucial role of PKA-dependent phosphorylation of α3GlyRs in inflammatory hyperalgesia.

Cyclooxygenase-2 induces neoplastic transformation by inhibiting p53-dependent oncogene-induced senescence

Much in vivo evidence indicates that cyclooxygenase-2 (COX-2) is deeply involved in tumorigenesis. Although it has been proposed that COX-2-derived pro-inflammatory prostanoids mediate the tumorigenic activity of COX-2, the tumorigenic mechanisms of COX-2 are not yet fully understood. Here, we investigated the mechanism by which COX-2 causes transformation from normal cells to malignant cells by using normal murine or human cells. We found that COX-2 inhibits the pro-senescent function of p53 under oncogenic RAS activation, by which it prevents oncogene-induced senescence (OIS) and induces neoplastic transformation. We also found that COX-2 physically interacts with p53 in the nucleus under oncogenic RAS activation, and that this COX-2-p53 interaction rather than the catalytic activity is involved in the COX-2-mediated inhibition of the pro-senescent function of p53 and OIS, and induction of neoplastic transformation. These findings strongly suggest that the oncogenic property of COX-2 is closely related to its ability to inactivate p53 under strong mitogenic signals, and that aberrant activation of the COX-2/a mitogenic oncogene combination can be a potent driving force for tumorigenesis. This study might contribute to our understanding of the molecular basis for the tumorigenic activity of COX-2 and the development of novel anti-tumor drugs targeting COX-2-p53 interactions.

Invited review: The role of the blood-milk barrier and its manipulation for the efficacy of the mammary immune response and milk production

The intact blood-milk barrier (BMB) prevents an uncontrolled exchange of soluble and cellular components between blood and milk in the mammary gland. It enables the sustainability of the optimal milk composition for the nourishment of the offspring. Endothelial cells, connective tissue, the basal membrane, and mainly the epithelial cells provide the semipermeability of this barrier, allowing only a selective transfer of components necessary for milk production. The epithelial cells are closely connected to each other by different formations, in which the tight junctions are the most critical for separating the milk-containing compartments from the surrounding extracellular fluid and vasculature. During mastitis, the integrity of the BMB is reduced. This facilitates the transfer of immune cells and immune factors such as antibodies from blood into milk. Simultaneously, the transfer of soluble blood constituents without an obvious immune function into milk is promoted. Furthermore, a reduced BMB integrity causes a loss of milk constituents into the blood circulation. Different mechanisms are responsible for the barrier impairment including tight junction opening, but also cell degradation. To promote the cure of mastitis, the targeted manipulation of the BMB permeability may be a tool to optimize the immune function of the mammary gland. An intensified opening of the BMB supports the antibody transfer from blood into milk, which is supposed to increase the contribution of the specific immune system in the immune defense. On the contrary, a fast closure of the BMB during the recovery from mastitis can accelerate the normalization of milk composition and milk yield. Various agents have been experimentally shown to either open (e.g., pathogens and pathogen-associated molecular patterns, several nonsteroidal anti-inflammatory drugs, oxytocin, calcium chelators) or close (e.g., glucocorticoids, nonsteroidal anti-inflammatory drugs, natural anti-inflammatory drugs) the BMB.

Immune-Mediated Mechanisms in Cofactor-Dependent Food Allergy and Anaphylaxis: Effect of Cofactors in Basophils and Mast Cells

Cofactors may explain why in some cases food ingestion leads to anaphylaxis while in others elicits a milder reaction or tolerance. With cofactors, reactions become more severe and/or have a lower allergen threshold. Cofactors are present in up to 58% of food anaphylaxis (FAn). Exercise, NSAIDs, and alcohol are the most frequently described, although the underlying mechanisms are poorly known. Several hypotheses have suggested the influence of these cofactors on basophils and mast cells (MCs). Exercise has been suggested to enhance MC activation by increasing plasma osmolarity, redistributing blood flow, and activating adenosine and eicosanoid metabolism. NSAIDs’ cofactor effect has been related with cyclooxygenase inhibition and therefore, prostaglandin E₂ (PGE₂) production. Indeed, overexpression of adenosine receptor 3 (A₃) gene has been described in NSAID-dependent FAn; A₃ activation potentiates FcϵRI-induced MC degranulation. Finally, alcohol has been related with an increase of histamine levels by inhibition of diamino oxidase (DAO) and also with and increase of extracellular adenosine by inhibition of its uptake. However, most of these mechanisms have limited evidence, and further studies are urgently needed. In conclusion, the study of the immune-related mechanisms involved in food allergic reactions enhanced by cofactors is of the utmost interest. This knowledge will help to design both tailored treatments and prophylactic strategies that, nowadays, are non-existent.

Dysfunctional Inflammation in Cystic Fibrosis Airways: From Mechanisms to Novel Therapeutic Approaches

Cystic fibrosis (CF) is an inherited disorder caused by mutations in the gene encoding for the cystic fibrosis transmembrane conductance regulator (CFTR) protein, an ATP-gated chloride channel expressed on the apical surface of airway epithelial cells. CFTR absence/dysfunction results in defective ion transport and subsequent airway surface liquid dehydration that severely compromise the airway microenvironment. Noxious agents and pathogens are entrapped inside the abnormally thick mucus layer and establish a highly inflammatory environment, ultimately leading to lung damage. Since chronic airway inflammation plays a crucial role in CF pathophysiology, several studies have investigated the mechanisms responsible for the altered inflammatory/immune response that, in turn, exacerbates the epithelial dysfunction and infection susceptibility in CF patients. In this review, we address the evidence for a critical role of dysfunctional inflammation in lung damage in CF and discuss current therapeutic approaches targeting this condition, as well as potential new treatments that have been developed recently. Traditional therapeutic strategies have shown several limitations and limited clinical benefits. Therefore, many efforts have been made to develop alternative treatments and novel therapeutic approaches, and recent findings have identified new molecules as potential anti-inflammatory agents that may exert beneficial effects in CF patients. Furthermore, the potential anti-inflammatory properties of CFTR modulators, a class of drugs that directly target the molecular defect of CF, also will be critically reviewed. Finally, we also will discuss the possible impact of SARS-CoV-2 infection on CF patients, with a major focus on the consequences that the viral infection could have on the persistent inflammation in these patients.

The Effect of LPS and Ketoprofen on Cytokines, Brain Monoamines, and Social Behavior in Group-Housed Pigs

Poor health is a risk factor for damaging behaviors, but the mechanisms behind this link are unknown. Injection of pigs with lipopolysaccharide (LPS) can be used to model aspects of poor health. Recent studies have shown that LPS-injected pigs perform more tail- and ear-directed behavior compared to saline-injected pigs and suggest that pro-inflammatory cytokines may play a role in these behaviors. The aims of this study were to test the effect of LPS on the social behavior of pigs and the neurotransmitters and modulators in their brains and to test the effect of a nonsteroidal anti-inflammatory drug on the effects of LPS. Fifty-two female pigs (11-12 weeks) were allocated to four treatments comprising two injections: saline-saline (SS), saline-LPS (SL), ketoprofen-saline (KS), and ketoprofen-LPS (KL). Activity was scan-sampled every 5 min for 6 h after the last injection in the pen. Social behavior was observed continuously in 10 × 15-min bouts between 8 a.m. and 5 p.m. 1 day before (baseline) and 1 and 2 days after the injection. Saliva was analyzed for cortisol and plasma for tryptophan and kynurenine. The frontal cortex, hippocampus, hypothalamus, and brain stem were sampled 72 h after the injection and analyzed for cytokines and monoamines. LPS activated the HPA axis and decreased the activity within 6 h after the injection. Ketoprofen lowered the effect of LPS on cortisol release and attenuated the behavioral signs of sickness in challenged pigs. SL pigs manipulated the ears of their pen mates significantly longer than SS pigs 2 days after the injection. LPS had no observed effect on IFN-γ, TNF-α, and IL-18. At 72 h after the injection, plasma tryptophan was depleted in SL pigs, and tryptophan and kynurenine concentrations in the frontal cortex and brain stem of SL pigs were significantly lower compared to those in SS pigs. Dopamine concentrations in the hypothalamus of SL pigs were significantly lower compared to those in SS pigs. Serotonin concentrations in the hypothalamus and noradrenaline concentrations in the hippocampus of SL pigs were significantly lower compared to those in KL pigs. In conclusion, LPS influenced the different neurotransmitters and modulators in the brain that are hypothesized to play an important role in the regulation of mood and behavior.

Inflammation and JNK's Role in Niacin-GPR109A Diminished Flushed Effect in Microglial and Neuronal Cells With Relevance to Schizophrenia

Schizophrenia is a neuropsychiatric illness with no single definitive aetiology, making its treatment difficult. Antipsychotics are not fully effective because they treat psychosis rather than the cognitive or negative symptoms. Antipsychotics fail to alleviate symptoms when patients enter the chronic stage of illness. Topical application of niacin showed diminished skin flush in the majority of patients with schizophrenia compared to the general population who showed flushing. The niacin skin flush test is useful for identifying patients with schizophrenia at their ultra-high-risk stage, and understanding this pathology may introduce an effective treatment. This review aims to understand the pathology behind the diminished skin flush response, while linking it back to neurons and microglia. First, it suggests that there are altered proteins in the GPR109A-COX-prostaglandin pathway, inflammatory imbalance, and kinase signalling pathway, c-Jun N-terminal kinase (JNK), which are associated with diminished flush. Second, genes from the GPR109A-COX-prostaglandin pathway were matched against the 128-loci genome wide association study (GWAS) for schizophrenia using GeneCards, suggesting that G-coupled receptor-109A (GPR109A) may have a genetic mutation, resulting in diminished flush. This review also suggests that there may be increased pro-inflammatory mediators in the GPR109A-COX-prostaglandin pathway, which contributes to the diminished flush pathology. Increased levels of pro-inflammatory markers may induce microglial-activated neuronal death. Lastly, this review explores the role of JNK on pro-inflammatory mediators, proteins in the GPR109A-COX-prostaglandin pathway, microglial activation, and neuronal death. Inhibiting JNK may reverse the changes observed in the diminished flush response, which might make it a good therapeutic target.

Effects of local or systemic administration of meloxicam on mammary gland inflammatory responses to lipopolysaccharide-induced mastitis in dairy cows

Nonsteroidal anti-inflammatory drugs (NSAID) are commonly used in combination with antimicrobial mastitis treatments to reduce pain. Little is known about whether meloxicam, an NSAID designed for the preferential inhibition of cyclooxygenase-2 over cyclooxygenase-1, affects the mammary immune response. The objective of this study was to analyze the mammary immune response to intramammary (local) or intravenous (systemic) administration of meloxicam with or without immune activation by lipopolysaccharide (LPS). We challenged 108 quarters of 30 cows with or without a low or high dose of LPS from Escherichia coli (0.1 or 0.2 µg/quarter), with or without meloxicam via intramammary administration (50 mg/quarter) or intravenous injection (0.5 mg/kg of body weight; ~300 mg/cow). Intramammary administration of meloxicam alone did not trigger an acute inflammatory response, verified by unchanged somatic cell count (SCC) and lactate dehydrogenase (LDH), BSA, and IgG concentrations in milk, which are normally augmented during mastitis due to an opening of the blood-milk barrier. Similarly, intramammary meloxicam did not change the mRNA abundance of inflammatory factors in mammary gland tissue. As expected, quarters challenged with either dose of LPS showed increased leukocyte infiltration (SCC); increased LDH, BSA, IgG, Na, and Cl concentrations; and diminished K concentrations in milk. In contrast to our hypothesis, the addition of intramammary or intravenous meloxicam did not reduce these markers of mastitis in milk. Instead, intramammary meloxicam appeared to accelerate the SCC response to LPS, but only at the lower LPS dose. Moreover, the mRNA expression of inflammatory factors in mammary tissue was not modified by the intramammary application of meloxicam compared with the contralateral quarters that were challenged with LPS only. We demonstrated for the first time that intramammary meloxicam at a dose of 50 mg/quarter did not trigger an immune response in the mammary glands of dairy cows. At the doses we used, meloxicam (intramammary or systemic) did not lower inflammatory responses. The intramammary administration of meloxicam seemed to stimulate leukocyte recruitment into the milk in quarters challenged with a low dose of LPS. The integrity of the blood-milk barrier was not protected by meloxicam in LPS-stimulated quarters. This study provides the first indications that meloxicam does not limit the inflammatory response in the mammary gland, although it does not impair the mammary immune system.

Therapeutic potential for coxibs-nitric oxide releasing hybrids in cystic fibrosis

This review discusses the rational for further studies of COX-2 inhibitors-NO releaser hybrids (NO-Coxibs) in the pharmacological treatment of the airway inflammation in Cystic Fibrosis (CF). Our research group developed several classes of NO-Coxibs for the pharmacological treatment of arthritis, and among them several compounds showed an outstanding in vivo efficacy and good pharmacokinetic properties. The good antiinflammatory properties displayed by these compounds during the previous screening could, by itself, suggest appropriate candidates for further testing in CF.

The Structural Basis for Nonsteroidal Anti-Inflammatory Drug Inhibition of Human Dihydrofolate Reductase

Although nonsteroidal anti-inflammatory drugs (NSAIDs) target primarily cyclooxygenase enzymes, a subset of NSAIDs containing carboxylate groups also has been reported to competitively inhibit dihydrofolate reductase (DHFR). In this study, we have characterized NSAID interactions with human DHFR based on kinetic, NMR, and X-ray crystallographic methods. The NSAIDs target a region of the folate binding site that interacts with the p-aminobenzoyl-l-glutamate (pABG) moiety of folate and inhibit cooperatively with ligands that target the adjacent pteridine-recognition subsite. NSAIDs containing benzoate or salicylate groups were identified as having the highest potency. Among those tested, diflunisal, a salicylate derivative not previously identified to have anti-folate activity, was found to have a K_i of 34 μM, well below peak plasma diflunisal levels reached at typical dosage levels. The potential of these drugs to interfere with the inflammatory process by multiple pathways introduces the possibility of further optimization to design dual-targeted analogs.

Calcium Permeable Channels in Cancer Hallmarks

Cancer, the second cause of death worldwide, is characterized by several common criteria, known as the “cancer hallmarks” such as unrestrained cell proliferation, cell death resistance, angiogenesis, invasion and metastasis. Calcium permeable channels are proteins present in external and internal biological membranes, diffusing Ca²⁺ ions down their electrochemical gradient. Numerous physiological functions are mediated by calcium channels, ranging from intracellular calcium homeostasis to sensory transduction. Consequently, calcium channels play important roles in human physiology and it is not a surprise the increasing number of evidences connecting calcium channels disorders with tumor cells growth, survival and migration. Multiple studies suggest that calcium signals are augmented in various cancer cell types, contributing to cancer hallmarks. This review focuses in the role of calcium permeable channels signaling in cancer with special attention to the mechanisms behind the remodeling of the calcium signals. Transient Receptor Potential (TRP) channels and Store Operated Channels (SOC) are the main extracellular Ca²⁺ source in the plasma membrane of non-excitable cells, while inositol trisphosphate receptors (IP₃R) are the main channels releasing Ca²⁺ from the endoplasmic reticulum (ER). Alterations in the function and/or expression of these calcium channels, as wells as, the calcium buffering by mitochondria affect intracellular calcium homeostasis and signaling, contributing to the transformation of normal cells into their tumor counterparts. Several compounds reported to counteract several cancer hallmarks also modulate the activity and/or the expression of these channels including non-steroidal anti-inflammatory drugs (NSAIDs) like sulindac and aspirin, and inhibitors of polyamine biosynthesis, like difluoromethylornithine (DFMO). The possible role of the calcium permeable channels targeted by these compounds in cancer and their action mechanism will be discussed also in the review.

Aspirin Induces Mitochondrial Ca2+ Remodeling in Tumor Cells via ROS‒Depolarization‒Voltage-Gated Ca2+ Entry

Aspirin (acetylsalicylic acid) and its metabolite salicylate, have an anti-melanoma effect by evoking mitochondrial dysfunction through poorly understood mechanisms. Depolarization of the plasma membrane potential leads to voltage-gated Ca²⁺ entry (VGCE) and caspase-3 activation. In the present study, we investigated the role of depolarization and VGCE in aspirin’s anti-melanoma effect. Aspirin and to a lesser extent, salicylate (≥2.5 mM) induced a rapid (within seconds) depolarization, while they caused comparable levels of depolarization with a lag of 2~4 h. Reactive oxygen species (ROS) generation also occurred in the two-time points, and antioxidants abolished the early ROS generation and depolarization. At the same concentrations, the two drugs induced apoptotic and necrotic cell death in a caspase-independent manner, and antioxidants and Ca²⁺ channel blockers prevented cell death. Besides ROS generation, reduced mitochondrial Ca²⁺ (Ca²⁺_m) and mitochondrial membrane potential preceded cell death. Moreover, the cells expressed the Ca_v1.2 isoform of l-type Ca²⁺ channel, and knockdown of Ca_v1.2 abolished the decrease in Ca²⁺_m. Our findings suggest that aspirin and salicylate induce Ca²⁺_m remodeling, mitochondrial dysfunction, and cell death via ROS-dependent depolarization and VGCE activation.

Response to and recovery from treatment in human liver-mimetic clinostat spheroids: a model for assessing repeated-dose drug toxicity

Medicines are usually prescribed for repeated use over shorter or longer times. Unfortunately, repeated-dose animal toxicity studies do not correlate well with observations in man. As emphasized by the '3Rs' and the desire to phase-out animal research, in vitro models are needed. One potential approach uses clinostat-cultured 3D HepG2-C3A liver-mimetic spheroids. They take 18 days to recover in vivo physiological functionality and reach a metabolic equilibrium, which is thereafter stable for a year. Acute and chronic repeated-dose studies of six drugs (amiodarone, diclofenac, metformin, phenformin, paracetamol and valproic acid) suggest that spheroids are more predictive of human in vivo toxicity than either 2D-cultured HepG2 cells or primary human hepatocytes. Repeated non-lethal treatment results in a clear response and return to equilibrium. Mitochondrial toxic compounds can be identified using a galactose-based medium. Some drugs induced a protective (or stress) response that intensifies after the second treatment. This 3D spheroid model is inexpensive, highly reproducible and well-suited for the determination of repeated-dose toxicity of compounds (naturally or chemically synthesized).

Pathomechanisms of Posttraumatic Osteoarthritis: Chondrocyte Behavior and Fate in a Precarious Environment

Traumatic injuries of the knee joint result in a wide variety of pathomechanisms, which contribute to the development of so-called posttraumatic osteoarthritis (PTOA). These pathogenetic processes include oxidative stress, excessive expression of catabolic enzymes, release of damage-associated molecular patterns (DAMPs), and synovial inflammation. The present review focuses on the underlying pathomechanisms of PTOA and in particular the behavior and fate of the surviving chondrocytes, comprising chondrocyte metabolism, regulated cell death, and phenotypical changes comprising hypertrophy and senescence. Moreover, possible therapeutic strategies, such as chondroanabolic stimulation, anti-oxidative and anti-inflammatory treatment, as well as novel therapeutic targets are discussed.

Anti-Inflammatory Activity of the Active Compounds of Sanguisorbae Radix In Macrophages and in Vivo Toxicity Evaluation in Zebrafish

Sanguisorbae Radix (SR) is the root of the Sanguisorba officinalis L., a plant native to Asian countries and used in traditional medicine. We isolated the active components of SR and investigated their anti-inflammatory potential. Quercetin (QC), (+)-catechin (CC), and gallic acid (GA) were isolated from acetone extracts of SR. To elucidate the molecular mechanism by which these compounds suppress inflammation, we analyzed the transcriptional up-regulation of inflammatory mediators, such as nuclear factor-kappa B (NF-κB) and its target genes, inducible NOS (iNOS), and cyclooxygenase (COX)-2, in lipopolysaccharide (LPS)-stimulated macrophage RAW264.7 cells. Notably, QC, CC, and GA were found to inhibit the production of nitric oxide, tumor necrosis factor-alpha, and prostaglandin in a dose-dependent manner. Western blot results indicate that the compounds decreased the expression of iNOS and COX-2 proteins. Furthermore, the compounds decreased phosphorylation of IKK, IκB, ERK, p-38, and JNK proteins in LPS-induced cells. The results support the notion that QC, CC, and GA can potently inhibit the inflammatory response, with QC showing the highest anti-inflammatory activity. In in vivo toxicity studies in zebrafish (Danio rerio), QC showed no toxicity up to 25 μg/mL. Therefore, QC has non-toxic potential as a skin anti-inflammatory biomaterial.

Anti-Inflammatory and Anti-Hyperuricemic Functions of Two Synthetic Hybrid Drugs with Dual Biological Active Sites

The present study aimed to test the anti-inflammatory and xanthine oxidase inhibitory activities of two synthesized molecules and compare them to routinely prescribed nonsteroidal anti-inflammatory drugs (NSAIDs), such as diclofenac and the serum urate-lowering drug, allopurinol. The anti-inflammatory effects of the designed compounds (A and B) were evaluated in carrageenan (CAR)-induced paw edema in mice. The levels of nitric oxide and myeloperoxidase activity were measured in paw skin using biochemical methods. Additionally, prostaglandin E2 (PGE2), C-reactive protein (CRP), cyclooxygenase-2 (Cox-2), tumor necrosis factor-α (TNFα), interleukin (IL)-1β, IL-2 and IL-10, and monocyte chemoattractant protein-1 (MCP1) were assessed by enzyme-linked immunosorbent assay (ELISA). The expression of inflammation-related genes was confirmed by real-time qPCR. The expression of inducible nitric oxide synthase (iNOS) and nuclear factor-kappa B (NF-κB) were estimated using immunohistochemistry, and xanthine oxidase inhibitory activity was evaluated using an in vitro assay. The results revealed that compounds A and B decreased inflammation, as was observed by a reduction in the elevation of all the tested markers. In addition, the tested compounds markedly decreased paw swelling, mobilization of inflammatory cells, iNOS-, and NF-κB-immunoreactive cells in a mouse model of paw edema. Interestingly, both compounds were potent xanthine oxidase inhibitors as well as Cox inhibitors with higher activity in favor of compound B providing potential dual acting series of anti-hyperuricemic and anti-inflammatory therapeutic agents.

The Effect of Biotinylated PAMAM G3 Dendrimers Conjugated with COX-2 Inhibitor (celecoxib) and PPARγ Agonist (Fmoc-L-Leucine) on Human Normal Fibroblasts, Immortalized Keratinocytes and Glioma Cells in Vitro

Glioblastoma multiforme (GBM) is the most malignant type of central nervous system tumor that is resistant to all currently used forms of therapy. Thus, more effective GBM treatment strategies are being investigated, including combined therapies with drugs that may cross the blood brain barrier (BBB). Another important issue considers the decrease of deleterious side effects of therapy. It has been shown that nanocarrier conjugates with biotin can penetrate BBB. In this study, biotinylated PAMAM G3 dendrimers substituted with the recognized anticancer agents cyclooxygenase-2 (COX-2) inhibitor celecoxib and peroxisome proliferator-activated receptor γ (PPARγ) agonist Fmoc-L-Leucine (G3-BCL) were tested in vitro on human cell lines with different p53 status: glioblastoma (U-118 MG), normal fibroblasts (BJ) and immortalized keratinocytes (HaCaT). G3-BCL penetrated efficiently into the lysosomal and mitochondrial compartments of U-118 MG cells and induced death of U-118 MG cells via apoptosis and inhibited proliferation and migration at low IC₅₀ = 1.25 µM concentration, considerably lower than either drug applied alone. Comparison of the effects of G3-BCL on expression of COX-2 and PPARγ protein and PGE₂ production of three different investigated cell line phenotypes revealed that the anti-glioma effect of the conjugate was realized by other mechanisms other than influencing PPAR-γ expression and regardless of p53 cell status, it was dependent on COX-2 protein level and high PGE₂ production. Similar G3-BCL cytotoxicity was seen in normal fibroblasts (IC₅₀ = 1.29 µM) and higher resistance in HaCaT cells (IC₅₀ = 4.49 µM). Thus, G3-BCL might be a good candidate for the targeted, local glioma therapy with limited site effects.

Targeting airway inflammation in cystic fibrosis

Introduction: The major cause of morbidity and mortality in patients with cystic fibrosis (CF) is lung disease. Inflammation in the CF airways occurs from a young age and contributes significantly to disease progression and shortened life expectancy. Areas covered: In this review, we discuss the key immune cells involved in airway inflammation in CF, the contribution of the intrinsic genetic defect to the CF inflammatory phenotype, and anti-inflammatory strategies designed to overcome what is a critical factor in the pathogenesis of CF lung disease. Review of the literature was carried out using the MEDLINE (from 1975 to 2018), Google Scholar and The Cochrane Library databases. Expert opinion: Therapeutic interventions specifically targeting the defective CF transmembrane conductance regulator (CFTR) protein have changed the clinical landscape and significantly improved the outlook for CF. As survival estimates for people with CF increase, long-term management has become an important focus, with an increased need for therapies targeted at specific elements of inflammation, to complement CFTR modulator therapies.

HDAC3 Activity is Essential for Human Leukemic Cell Growth and the Expression of β-catenin, MYC, and WT1

Therapy of acute myeloid leukemia (AML) is unsatisfactory. Histone deacetylase inhibitors (HDACi) are active against leukemic cells in vitro and in vivo. Clinical data suggest further testing of such epigenetic drugs and to identify mechanisms and markers for their efficacy. Primary and permanent AML cells were screened for viability, replication stress/DNA damage, and regrowth capacities after single exposures to the clinically used pan-HDACi panobinostat (LBH589), the class I HDACi entinostat/romidepsin (MS-275/FK228), the HDAC3 inhibitor RGFP966, the HDAC6 inhibitor marbostat-100, the non-steroidal anti-inflammatory drug (NSAID) indomethacin, and the replication stress inducer hydroxyurea (HU). Immunoblotting was used to test if HDACi modulate the leukemia-associated transcription factors β-catenin, Wilms tumor (WT1), and myelocytomatosis oncogene (MYC). RNAi was used to delineate how these factors interact. We show that LBH589, MS-275, FK228, RGFP966, and HU induce apoptosis, replication stress/DNA damage, and apoptotic fragmentation of β-catenin. Indomethacin destabilizes β-catenin and potentiates anti-proliferative effects of HDACi. HDACi attenuate WT1 and MYC caspase-dependently and -independently. Genetic experiments reveal a cross-regulation between MYC and WT1 and a regulation of β-catenin by WT1. In conclusion, reduced levels of β-catenin, MYC, and WT1 are molecular markers for the efficacy of HDACi. HDAC3 inhibition induces apoptosis and disrupts tumor-associated protein expression.

Can intravesical application of paracetamol benefit the chemotherapy treatment of bladder cancer?

Bladder cancer is one of the most common urogenital tumors. Its prevalence is increasing worldwide, especially men. The cyclooxygenase-2 (COX-2) enzyme has been shown to increase in bladder cancer and has a direct relationship with tumor progression. Non-steroidal anti-inflammatory drugs (NSAIDs) reduce the growth of the tumor by inhibiting the COX-2 enzyme. NSAIDs have other effects unrelated to COX that provide anticancer properties. Also, similar to NSAIDs, anticancer effects of paracetamol have been shown in many studies. Therefore we hypothesize intravesical paracetamol application will have beneficial effects in the treatment of non-muscle invasive bladder cancer (NMBIC).

Map and model-moving from observation to prediction in toxicogenomics

BACKGROUND

Chemicals induce compound-specific changes in the transcriptome of an organism (toxicogenomic fingerprints). This provides potential insights about the cellular or physiological responses to chemical exposure and adverse effects, which is needed in assessment of chemical-related hazards or environmental health. In this regard, comparison or connection of different experiments becomes important when interpreting toxicogenomic experiments. Owing to lack of capturing response dynamics, comparability is often limited. In this study, we aim to overcome these constraints.

RESULTS

We developed an experimental design and bioinformatic analysis strategy to infer time- and concentration-resolved toxicogenomic fingerprints. We projected the fingerprints to a universal coordinate system (toxicogenomic universe) based on a self-organizing map of toxicogenomic data retrieved from public databases. Genes clustering together in regions of the map indicate functional relation due to co-expression under chemical exposure. To allow for quantitative description and extrapolation of the gene expression responses we developed a time- and concentration-dependent regression model. We applied the analysis strategy in a microarray case study exposing zebrafish embryos to 3 selected model compounds including 2 cyclooxygenase inhibitors. After identification of key responses in the transcriptome we could compare and characterize their association to developmental, toxicokinetic, and toxicodynamic processes using the parameter estimates for affected gene clusters. Furthermore, we discuss an association of toxicogenomic effects with measured internal concentrations.

CONCLUSIONS

The design and analysis pipeline described here could serve as a blueprint for creating comparable toxicogenomic fingerprints of chemicals. It integrates, aggregates, and models time- and concentration-resolved toxicogenomic data.

Anti-inflammatory effects of Phytodolor® (STW 1) and components (poplar, ash and goldenrod) on human monocytes/macrophages

BACKGROUND

Populus tremula L. (Poplar), Fraxinus excelsior L. (ash) and Solidago virgaurea L. (goldenrod) have been used for medicinal purposes through centuries, to treat pain, fever and inflammation, but their mechanisms of action are still not fully understood. The present study was performed to investigate, whether the herbal medicinal product Phytodolor^® (STW 1) and its components have anti-inflammatory effects on activated human monocytes and differentiated human macrophages to elucidate their modes of action in comparison with well-known analgesic, non-steroidal anti-inflammatory drug (NSAIDs) as diclofenac.

METHODS

Adherent human monocytes obtained from peripheral blood mononuclear cells (PBMCs) were cultured in serum-free medium and pre-treated with 50-100 µg/ml of diclofenac, STW 1, their components, poplar, ash or goldenrod or its combination (0.05% to 2%). Thereafter, monocytes were activated with 0.1 or 1 µg/ml LPS for 24 h. The intracellular expressions of TNF-α or PTGS2 were determined by cell-based ELISA. Apoptotic cells were identified by YO-PRO-1 staining. Protein or total RNA were isolated to perform SDS-PAGE/Western blot and qRT-PCR analyses. PMA-differentiated human THP-1 macrophages were pre-treated with diclofenac (50 µg/ml) or STW1 (0.1%) and afterwards with LPS (1 µg/ml) and the translocation of the intracellular p62 NF-κB subunit was detected by immunofluorescence.

RESULTS

STW 1 inhibited the intracellular content of TNF-α and PTGS2 protein, as well as of TNF-α and PTGS2 gene expression and induced apoptosis in LPS-activated human monocytes under serum free conditions. Furthermore, STW 1 inhibited the translocation of the p65 subunit of the redox-regulated NF-κB into the nucleus in LPS-activated human macrophages.

CONCLUSION

The present in vitro investigations suggest a significant anti-inflammatory activity of STW 1 and its components by inhibiting pro-inflammatory cytokine as TNF-α and the key enzyme PTGS2 in LPS-activated human monocytes, which is, at least partly mediated through the suppression of NF-κB activation. Our results provide evidence for distinctive anti-inflammatory effects of STW 1 and its components on LPS-activated human monocytes/macrophages and, thus, for the therapeutic use of STW 1 in inflammation and pain related disorders.

Modulation of Skin Inflammatory Response by Active Components of Silymarin

In this study, we compared selected silymarin components, such as quercetin (QE), 2,3-dehydrosilybin (DHS) and silybin (SB), with the anti-inflammatory drug indomethacin (IND) in terms of their wound healing potential. In view of the fact that pathological cutaneous wound healing is associated with persistent inflammation, we studied their anti-inflammatory activity against inflammation induced by bacterial lipopolysaccharide (LPS). We investigated the regulation of crucial pro-inflammatory transcription factors—nuclear factor kappa-B (NF-κB) and activator protein 1 (AP-1)—as well as the expression of downstream inflammatory targets by Western blotting, real-time PCR (RT-PCR), electrophoretic mobility shift assay (EMSA), and/or enzyme-linked immunosorbent assay (ELISA) in vitro using primary normal human dermal fibroblasts (NHDF). We demonstrated the greater ability of DHS to modulate the pro-inflammatory cytokines production via the NF-κB and AP-1 signaling pathways when compared to other tested substances. The prolonged exposure of LPS-challenged human dermal fibroblasts to DHS had both beneficial and detrimental consequences. DHS diminished interleukin-6 (IL-6) and interleukin-8 (IL-8) secretion but induced the significant upregulation of IL-8 mRNA associated with NF-κB and AP-1 activation. The observed conflicting results may compromise the main expected benefit, which is the acceleration of the healing of the wound via a diminished inflammation.

A Review of Chronic Musculoskeletal Pain: Central and Peripheral Effects of Diclofenac

Diclofenac is widely used to manage chronic inflammatory and degenerative joint diseases such as osteoarthritis (OA), rheumatoid arthritis (RA), ankylosing spondylitis, and extra-articular rheumatism. Its various mechanisms of action make it particularly effective in treating nociceptive pain, but it is also an alternative for treating spinal and chronic central pain. Osteoarthritis and rheumatoid arthritis are the most frequently encountered arthritic conditions in adults. The management of nociceptive pain requires a sequential hierarchical approach, with the initial NSAID treatment being characterized by the replacement of one drug with another, or complete discontinuation usually because of insufficient pain control. OA- and RA-related pain is complex and multifactorial, and due to physiological interactions between the signaling of the central and peripheral nervous systems. The mechanisms of action of diclofenac make it particularly effective in treating both nociceptive pain and chronic central pain. This review underlines the mechanisms of diclofenac involved in chronic and acute joint pain, the most relevant adverse events.