Aspirin and Celecoxib Regulate Notch1/Hes1 Pathway to Prevent Pressure Overload-Induced Myocardial Hypertrophy.

This study aimed to investigate the molecular mechanisms underlying the protective effects of cyclooxygenase (cox) inhibitors against myocardial hypertrophy.Rat H9c2 cardiomyocytes were induced by mechanical stretching. SD rats underwent transverse aortic constriction to induce pressure overload myocardial hypertrophy. Rats were subjected to echocardiography and tail arterial pressure in 12W. qPCR and western blot were used to detect the expression of Notch-related signaling. The inflammatory factors were tested by ELISA in serum, heart tissue, and cell culture supernatant.Compared with control, levels of pro-inflammatory cytokines IL-6, TNF-α, and IL-1ß were increased and anti-inflammatory cytokine IL-10 was reduced in myocardial tissues and serum of rat models. Levels of Notch1 and Hes1 were reduced in myocardial tissues. However, cox inhibitor treatment (aspirin and celecoxib), the improvement of exacerbated myocardial hypertrophy, fibrosis, dysfunction, and inflammation was parallel to the activation of Notch1/Hes1 pathway. Moreover, in vitro experiments showed that, in cardiomyocyte H9c2 cells, application of ~20% mechanical stretching activated inflammatory mediators (IL-6, TNF-α, and IL-1ß) and hypertrophic markers (ANP and BNP). Moreover, expression levels of Notch1 and Hes1 were decreased. These changes were effectively alleviated by aspirin and celecoxib.Cox inhibitors may protect heart from hypertrophy and inflammation possibly via the Notch1/Hes1 signaling pathway.

Structural Characterization, and Antioxidative and Anti-inflammatory Activities of Phylloxanthobilins in Tropaeolum majus, a Plant with Relevance in Phytomedicine.

Tropaeolum majus (garden nasturtium) is a plant with relevance in phytomedicine, appreciated not only for its pharmaceutical activities, but also for its beautiful leaves and flowers. Here, we investigated the phytochemical composition of senescent nasturtium leaves. Indeed, we identified yellow chlorophyll catabolites, also termed phylloxanthobilins, which we show to contribute to the bright yellow color of the leaves in the autumn season. Moreover, we isolated and characterized the phylloxanthobilins from T. majus, and report the identification of a pyro-phylloxanthobilin, so far only accessible by chemical synthesis. We show that the phylloxanthobilins contribute to bioactivities of T. majus by displaying strong anti-oxidative effects in vitro and in cellulo, and anti-inflammatory effects as assessed by COX-1 and COX-2 enzyme inhibition, similar to other bioactive ingredients of T. majus, isoquercitrin, and chlorogenic acid. Hence, phylloxanthobilins could play a role in the efficacy of T. majus in the treatment of urinary tract infections, an established indication of T. majus. With the results shown in this study, we aid in the completion of the phytochemical profile of T. majus by identifying additional bioactive natural products as relevant components of this medicinal plant.

New insights into the anti-inflammatory and anti-melanoma mechanisms of action of azelaic acid and other Fusarium solani metabolites via in vitro and in silico studies.

Metabolites exploration of the ethyl acetate extract of Fusarium solani culture broth that was isolated from Euphorbia tirucalli root afforded five compounds; 4-hydroxybenzaldehyde (1), 4-hydroxybenzoic acid (2), tyrosol (3), azelaic acid (4), malic acid (5), and fusaric acid (6). Fungal extract as well as its metabolites were evaluated for their anti-inflammatory and anti-hyperpigmentation potential via in vitro cyclooxygenases and tyrosinase inhibition assays, respectively. Azelaic acid (4) exhibited powerful and selective COX-2 inhibition followed by fusaric acid (6) with IC50 values (2.21 ± 0.06 and 4.81 ± 0.14 µM, respectively). As well, azelaic acid (4) had the most impressive tyrosinase inhibitory effect with IC50 value of 8.75 ± 0.18 µM compared to kojic acid (IC50 = 9.27 ± 0.19 µM). Exclusive computational studies of azelaic acid and fusaric acid with COX-2 were in good accord with the in vitro results. Interestingly, this is the first time to investigate and report the potential of compounds 3-6 to inhibit cyclooxygenase enzymes. One of the most invasive forms of skin cancer is melanoma, a molecular docking study using a set of enzymes related to melanoma suggested pirin to be therapeutic target for azelaic acid and fusaric acid as a plausible mechanism for their anti-melanoma activity.

Adjuvant COX inhibition augments STING signaling and cytolytic T cell infiltration in irradiated 4T1 tumors.

Immune therapy is the new frontier of cancer treatment. Therapeutic radiation is a known inducer of immune response and can be limited by immunosuppressive mediators including cyclooxygenase-2 (COX2) that is highly expressed in aggressive triple negative breast cancer (TNBC). A clinical cohort of TNBC tumors revealed poor radiation therapeutic efficacy in tumors expressing high COX2. Herein, we show that radiation combined with adjuvant NSAID (indomethacin) treatment provides a powerful combination to reduce both primary tumor growth and lung metastasis in aggressive 4T1 TNBC tumors, which occurs in part through increased antitumor immune response. Spatial immunological changes including augmented lymphoid infiltration into the tumor epithelium and locally increased cGAS/STING1 and type I IFN gene expression were observed in radiation-indomethacin-treated 4T1 tumors. Thus, radiation and adjuvant NSAID treatment shifts "immune desert phenotypes" toward antitumor M1/TH1 immune mediators in these immunologically challenging tumors. Importantly, radiation-indomethacin combination treatment improved local control of the primary lesion, reduced metastatic burden, and increased median survival when compared with radiation treatment alone. These results show that clinically available NSAIDs can improve radiation therapeutic efficacy through increased antitumor immune response and augmented local generation of cGAS/STING1 and type I IFNs.

Experimental and Machine-Learning-Assisted Design of Pharmaceutically Acceptable Deep Eutectic Solvents for the Solubility Improvement of Non-Selective COX Inhibitors Ibuprofen and Ketoprofen.

Deep eutectic solvents (DESs) are commonly used in pharmaceutical applications as excellent solubilizers of active substances. This study investigated the tuning of ibuprofen and ketoprofen solubility utilizing DESs containing choline chloride or betaine as hydrogen bond acceptors and various polyols (ethylene glycol, diethylene glycol, triethylene glycol, glycerol, 1,2-propanediol, 1,3-butanediol) as hydrogen bond donors. Experimental solubility data were collected for all DES systems. A machine learning model was developed using COSMO-RS molecular descriptors to predict solubility. All studied DESs exhibited a cosolvency effect, increasing drug solubility at modest concentrations of water. The model accurately predicted solubility for ibuprofen, ketoprofen, and related analogs (flurbiprofen, felbinac, phenylacetic acid, diphenylacetic acid). A machine learning approach utilizing COSMO-RS descriptors enables the rational design and solubility prediction of DES formulations for improved pharmaceutical applications.

Urothelium-derived prostanoids enhance contractility of urinary bladder smooth muscle and stimulate bladder afferent nerve activity in the mouse.

The transitional epithelial cells (urothelium) that line the lumen of the urinary bladder form a barrier between potentially harmful pathogens, toxins, and other bladder contents and the inner layers of the bladder wall. The urothelium, however, is not simply a passive barrier, as it can produce signaling factors, such as ATP, nitric oxide, prostaglandins, and other prostanoids, that can modulate bladder function. We investigated whether substances produced by the urothelium could directly modulate the contractility of the underlying urinary bladder smooth muscle. Force was measured in isolated strips of mouse urinary bladder with the urothelium intact or denuded. Bladder strips developed spontaneous tone and phasic contractions. In urothelium-intact strips, basal tone, as well as the frequency and amplitude of phasic contractions, were 25%, 32%, and 338% higher than in urothelium-denuded strips, respectively. Basal tone and phasic contractility in urothelium-intact bladder strips were abolished by the cyclooxygenase (COX) inhibitor indomethacin (10 µM) or the voltage-dependent Ca2+ channel blocker diltiazem (50 µM), whereas blocking neuronal sodium channels with tetrodotoxin (1 µM) had no effect. These results suggest that prostanoids produced in the urothelium enhance smooth muscle tone and phasic contractions by activating voltage-dependent Ca2+ channels in the underlying bladder smooth muscle. We went on to demonstrate that blocking COX inhibits the generation of transient pressure events in isolated pressurized bladders and greatly attenuates the afferent nerve activity during bladder filling, suggesting that urothelial prostanoids may also play a role in sensory nerve signaling.NEW & NOTEWORTHY This paper provides evidence for the role of urothelial-derived prostanoids in maintaining tone in the urinary bladder during bladder filling, not only underscoring the role of the urothelium as more than a barrier but also contributing to active regulation of the urinary bladder. Furthermore, cyclooxygenase products greatly augment sensory nerve activity generated by bladder afferents during bladder filling and thus may play a role in perception of bladder fullness.

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

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

Exploration of isoxazole analogs: Synthesis, COX inhibition, anticancer screening, 3D multicellular tumor spheroids, and molecular modeling.

In this study, a new series of Isoxazole-carboxamide derivatives were synthesized and characterized via HRMS, 1H-, 13CAPT-NMR, and MicroED. The findings revealed that nearly all of the synthesized derivatives exhibited potent inhibitory activities against both COX enzymes, with IC50 values ranging from 4.1 nM to 3.87 µM. Specifically, MYM1 demonstrated the highest efficacy among the compounds tested against the COX-1, displaying an IC50 value of 4.1 nM. The results showed that 5 compounds possess high COX-2 isozyme inhibitory effects with IC50 value in range 0.24-1.30 µM with COX-2 selectivity indexes (2.51-6.13), among these compounds MYM4 has the lowest IC50 value against COX-2, with selectivity index around 4. Intriguingly, this compound displayed significant antiproliferative effects against CaCo-2, Hep3B, and HeLa cancer cell lines, with IC50 values of 10.22, 4.84, and 1.57 µM, respectively, which was nearly comparable to that of doxorubicin. Compound MYM4 showed low cytotoxic activities on normal cell lines LX-2 and Hek293t with IC50 values 20.01 and 216.97 µM respectively, with safer values than doxorubicin. Furthermore, compound MYM4 was able to induce the apoptosis, suppress the colonization of both HeLa and HepG2 cells. Additionally, the induction of Reactive oxygen species (ROS) production could be the mechanism underlying the apoptotic effect and the cytotoxic activity of the compound. In the 3D multicellular tumor spheroid model, results revealed that MYM4 compound hampered the spheroid formation capacity of Hep3B and HeLa cancer cells. Moreover, the molecular docking of MYM4 compound revealed a high affinity for the COX2 enzyme, with energy scores (S) -7.45 kcal/mol, which were comparable to celecoxib (S) -8.40 kcal/mol. Collectively, these findings position MYM4 as a promising pharmacological candidate as COX inhibitor and anticancer agent.

Discovery of new 2-(3-(naphthalen-2-yl)-4,5-dihydro-1H-pyrazol-1-yl)thiazole derivatives with potential analgesic and anti-inflammatory activities: In vitro, in vivo and in silico investigations.

Joining the global demand for the discovery of potent NSAIDs with minimized ulcerogenic effect, new pyrazole clubbed thiazole derivatives 5a-o were designed and synthesized. The new derivatives were initially evaluated for their analgesic activity. Eight compounds 5a, 5c, 5d, 5e, 5f, 5h, 5m, and 5o showed higher activity than Indomethacin (potency = 105-130 % vs. 100 %). Subsequently, they were picked for further evaluation of their anti-inflammatory activity, ulcerogenic liability as well as toxicological studies. Derivatives 5h and 5m showed a potential % edema inhibition after 3 h (79.39 % and 72.12 %, respectively), with a promising safety profile and low ulcer indices (3.80 and 3.20, respectively). The two compounds 5h and 5m were subjected to in vitro COX-1 and COX-2 inhibition assay. The candidate 5h showed nearly equipotent COX-1 inhibition (IC50 = 38.76 nM) compared to the non-selective reference drug Indomethacin (IC50 = 35.72 nM). Compound 5m expressed significant inhibitory activities and a higher COX-2 selectivity index (IC50 = 87.74 nM, SI = 2.05) in comparison with Indomethacin (SI = 0.52), with less selectivity than Celecoxib (SI = 8.31). Simulation docking studies were carried out to gain insights into the binding interaction of compounds 5h and 5m in the vicinity of COX-1 and COX-2 enzymes that illustrated the importance of pyrazole clubbed thiazole core in hydrogen bonding interactions. The thiazole motif of compounds 5h and 5m exhibited a well orientation toward COX-1 Arg120 key residue by hydrogen bonding interactions. Compound 5h revealed an additional arene-cation interaction with Arg120 that could rationalize its superior COX-1 inhibitory activity. Compounds 5h and 5m overlaid the co-crystallized ligand Celecoxib I differently in the active site of COX-2. Compound 5m showed an enhanced accommodation with binding energy of - 6.13 vs. - 1.70 kcal/mol of compounds 5h. The naphthalene ring of compound 5m adopted the Celecoxib I benzene sulfonamide region that is stabilized by hydrogen-arene interactions with the hydrophobic sidechains of the key residues Ser339 and Phe504. Further, the core structure of compound 5m, pyrazole clubbed thiazole, revealed deeper hydrophobic interactions with Ala513, Leu517 and Val509 residues. Finally, a sensitive and accurate UPLC-MS/MS method was developed for the simultaneous estimation of some selected promising pyrazole derivatives in rat plasma. Accordingly, compounds 5h and 5m were suggested to be promising potent analgesic and anti-inflammatory agents with improved safety profiles and a novel COX isozyme modulation activity.

Antagonistic effects of a COX1/2 inhibitor drug in human HepG2 cells exposed to an environmental carcinogen.

Understanding interactions between legacy and emerging environmental contaminants has important implications for risk assessment, especially when mutagens and carcinogens are involved, whose critical effects are chronic and therefore difficult to predict. The current work aimed to investigate potential interactions between benzo[a]pyrene (B[a]P), a carcinogenic polycyclic aromatic hydrocarbon and legacy pollutant, and diclofenac (DFC), a non-steroidal anti-inflammatory drug and pollutant of emerging concern, and how DFC affects B[a]P toxicity. Exposure to binary mixtures of these chemicals resulted in substantially reduced cytotoxicity in human HepG2 cells compared to single-chemical exposures. Significant antagonistic effects were observed in response to high concentrations of B[a]P in combination with DFC at IC50 and ⅕ IC50. While additive effects were found for levels of intracellular reactive oxygen species, antagonistic mixture effects were observed for genotoxicity. B[a]P induced DNA strand breaks, γH2AX activation, and micronuclei formation at ½ IC50 concentrations or lower, whereas DFC induced only low levels of DNA strand breaks. Their mixture caused significantly lower levels of genotoxicity by all three endpoints compared to those expected based on concentration additivity. In addition, antagonistic mixture effects on CYP1 enzyme activity suggested that the observed reduced genotoxicity of B[a]P was due to its reduced metabolic activation as a result of enzymatic inhibition by DFC. Overall, the findings further support the growing concern that co-exposure to environmental toxicants and their non-additive interactions may be a confounding factor that should not be neglected in environmental and human health risk assessment.

Exploring of novel oxazolones and imidazolones as anti-inflammatory and analgesic candidates with cyclooxygenase inhibitory action.

Aim: Over the last few decades, therapeutic needs have led to a search for safer COX-2 inhibitors with potential anti-inflammatory and analgesic activity. Materials & methods: A new series of oxazolone and imidazolone derivatives 3a-c and 4a-r were synthesized and evaluated as anti-inflammatory and analgesic agents. COX-1/COX-2 isozyme selectivity testing and molecular docking were performed. Results: All compounds showed good activities comparable to those of the reference, celecoxib. The most active compounds 3a, 4a, 4c, 4e and 4f showed promising gastric tolerability with an ulcer index lower than that of celecoxib. The molecular docking of p-methoxyphenyl derivative 4c showed alkyl interaction with the side pocket His75 of COX-2 and achieved the best anti-inflammatory activity, with a COX-2 selectivity index better than that of celecoxib.

[Box: see text].

Dihydroartemisinin, a potential PTGS1 inhibitor, potentiated cisplatin-induced cell death in non-small cell lung cancer through activating ROS-mediated multiple signaling pathways.

Dihydroartemisinin (DHA) exerts an anti-tumor effect in multiple cancers, however, the molecular mechanism of DHA and whether DHA facilitates the anti-tumor efficacy of cisplatin in non-small cell lung cancer (NSCLC) are unclear. Here, we found that DHA potentiated the anti-tumor effects of cisplatin in NSCLC cells by stimulating reactive oxygen species (ROS)-mediated endoplasmic reticulum (ER) stress, C-Jun-amino-terminal kinase (JNK) and p38 MAPK signaling pathways both in vitro and in vivo. Of note, we demonstrated for the first time that DHA inhibits prostaglandin G/H synthase 1 (PTGS1) expression, resulting in enhanced ROS production. Importantly, silencing PTGS1 sensitized DHA-induced cell death by increasing ROS production and activating ER-stress, JNK and p38 MAPK signaling pathways. In summary, our findings provided new experimental basis and therapeutic prospect for the combined therapy with DHA and cisplatin in some NSCLC patients.

Cyclooxygenase products contribute to the exaggerated exercise pressor reflex evoked by static muscle contraction in male UCD-type 2 diabetes mellitus rats.

Cyclooxygenase (COX) products of arachidonic acid metabolism, specifically prostaglandins, play a role in evoking and transmitting the exercise pressor reflex in health and disease. Individuals with type 2 diabetes mellitus (T2DM) have an exaggerated exercise pressor reflex; however, the mechanisms for this exaggerated reflex are not fully understood. We aimed to determine the role played by COX products in the exaggerated exercise pressor reflex in T2DM rats. The exercise pressor reflex was evoked by static muscle contraction in unanesthetized, decerebrate, male, adult University of California Davis (UCD)-T2DM (n = 8) and healthy Sprague-Dawley (n = 8) rats. Changes (Δ) in peak mean arterial pressure (MAP) and heart rate (HR) during muscle contraction were compared before and after intra-arterial injection of indomethacin (1 mg/kg) into the contracting hindlimb. Data are presented as means ± SD. Inhibition of COX activity attenuated the exaggerated peak MAP (Before: Δ32 ± 13 mmHg and After: Δ18 ± 8 mmHg; P = 0.004) and blood pressor index (BPi) (Before: Δ683 ± 324 mmHg·s and After: Δ361 ± 222 mmHg·s; P = 0.006), but not HR (Before: Δ23 ± 8 beats/min and After Δ19 ± 10 beats/min; P = 0.452) responses to muscle contraction in T2DM rats. In healthy rats, COX activity inhibition did not affect MAP, HR, or BPi responses to muscle contraction. Inhibition of COX activity significantly reduced local production of prostaglandin E2 in T2DM and healthy rats. We conclude that peripheral inhibition of COX activity attenuates the pressor response to muscle contraction in T2DM rats, suggesting that COX products partially contribute to the exaggerated exercise pressor reflex in those with T2DM.NEW & NOTEWORTHY We compared the pressor and cardioaccelerator responses to static muscle contraction before and after inhibition of cyclooxygenase (COX) activity within the contracting hindlimb in decerebrate, unanesthetized type 2 diabetic mellitus (T2DM) and healthy rats. The pressor responses to muscle contraction were attenuated after peripheral inhibition of COX activity in T2DM but not in healthy rats. We concluded that COX products partially contribute to the exaggerated pressor reflex in those with T2DM.

The impact of the route of administration on the efficacy and safety of the drug therapy for patent ductus arteriosus in premature infants: a systematic review and meta-analysis.

Background: This systematic review and meta-analysis aims to explore the potential impact of the route of administration on the efficacy of therapies and occurrence of adverse events when administering medications to premature infants with patent ductus arteriosus (PDA). Method: The protocol for this review has been registered with PROSPERO (CRD 42022324598). We searched relevant studies in PubMed, Embase, Cochrane, and the Web of Science databases from March 26, 1996, to January 31, 2022. Results: A total of six randomized controlled trials (RCTs) and five observational studies were included for analysis, involving 630 premature neonates in total. Among these infants, 480 were in the ibuprofen group (oral vs. intravenous routes), 78 in the paracetamol group (oral vs. intravenous routes), and 72 in the ibuprofen group (rectal vs. oral routes). Our meta-analysis revealed a significant difference in the rate of PDA closure between the the initial course of oral ibuprofen and intravenous ibuprofen groups (relative risk (RR) = 1.27, 95% confidence interval (CI) [1.13-1.44]; P < 0.0001, I2 = 0%). In contrast, the meta-analysis of paracetamol administration via oral versus intravenous routes showed no significant difference in PDA closure rates (RR = 0.86, 95% CI [0.38-1.91]; P = 0.71, I2 = 76%). However, there was no statistically significant difference in the risk of adverse events or the need for surgical intervention among various drug administration methods after the complete course of drug therapy. Conclusion: This meta-analysis evaluated the safety and effectiveness of different medication routes for treating PDA in premature infants. Our analysis results revealed that compared with intravenous administration, oral ibuprofen may offer certain advantages in closing PDA without increasing the risk of adverse events. Conversely, the use of paracetamol demonstrated no significant difference in PDA closure and the risk of adverse events between oral and intravenous administration.

Trial of Selective Early Treatment of Patent Ductus Arteriosus with Ibuprofen.

BACKGROUND: The cyclooxygenase inhibitor ibuprofen may be used to treat patent ductus arteriosus (PDA) in preterm infants. Whether selective early treatment of large PDAs with ibuprofen would improve short-term outcomes is not known. METHODS: We conducted a multicenter, randomized, double-blind, placebo-controlled trial evaluating early treatment (≤72 hours after birth) with ibuprofen for a large PDA (diameter of ≥1.5 mm with pulsatile flow) in extremely preterm infants (born between 23 weeks 0 days' and 28 weeks 6 days' gestation). The primary outcome was a composite of death or moderate or severe bronchopulmonary dysplasia evaluated at 36 weeks of postmenstrual age. RESULTS: A total of 326 infants were assigned to receive ibuprofen and 327 to receive placebo; 324 and 322, respectively, had data available for outcome analyses. A primary-outcome event occurred in 220 of 318 infants (69.2%) in the ibuprofen group and 202 of 318 infants (63.5%) in the placebo group (adjusted risk ratio, 1.09; 95% confidence interval [CI], 0.98 to 1.20; P = 0.10). A total of 44 of 323 infants (13.6%) in the ibuprofen group and 33 of 321 infants (10.3%) in the placebo group died (adjusted risk ratio, 1.32; 95% CI, 0.92 to 1.90). Among the infants who survived to 36 weeks of postmenstrual age, moderate or severe bronchopulmonary dysplasia occurred in 176 of 274 (64.2%) in the ibuprofen group and 169 of 285 (59.3%) in the placebo group (adjusted risk ratio, 1.09; 95% CI, 0.96 to 1.23). Two unforeseeable serious adverse events occurred that were possibly related to ibuprofen. CONCLUSIONS: The risk of death or moderate or severe bronchopulmonary dysplasia at 36 weeks of postmenstrual age was not significantly lower among infants who received early treatment with ibuprofen than among those who received placebo. (Funded by the National Institute for Health Research Health Technology Assessment Programme; Baby-OSCAR ISRCTN Registry number, ISRCTN84264977.).

Neuropeptide W facilitates chronic gastric ulcer healing by the regulation of cyclooxygenase and NF-κB signaling pathways.

AIMS: Putative beneficial effects of neuropeptide W (NPW) in the early phase of gastric ulcer healing process and the involvement of cyclooxygenase (COX) enzymes were investigated in an acetic acid-induced gastric ulcer model. MAIN METHODS: In anesthetized male Sprague-Dawley rats, acetic acid was applied surgically on the serosa and then a COX-inhibitor (COX-2-selective NS-398, COX-1-selective ketorolac, or non-selective indomethacin; 2 mg/kg/day, 3 mg/kg/day or 5 mg/kg/day; respectively) or saline was injected intraperitoneally. One h after ulcer induction, omeprazole (20 mg/kg/day), NPW (0.1 µg/kg/day) or saline was intraperitoneally administered. Injections of NPW, COX-inhibitors, omeprazole or saline were continued for the following 2 days until rats were decapitated at the end of the third day. KEY FINDINGS: NPW treatment depressed gastric prostaglandin (PG) I2 level, but not PGE2 level. Similar to omeprazole, NPW treatment significantly reduced gastric and serum tumor necrosis factor-alpha and interleukin-1 beta levels and depressed the upregulation of nuclear factor kappa B (NF-κB) and COX-2 expressions due to ulcer. In parallel with the histopathological findings, treatment with NPW suppressed ulcer-induced increases in myeloperoxidase activity and malondialdehyde level and replenished glutathione level. However, the inhibitory effect of NPW on myeloperoxidase activity and NPW-induced increase in glutathione were not observed in the presence of COX-1 inhibitor ketorolac or the non-selective COX-inhibitor indomethacin. SIGNIFICANCE: In conclusion, NPW facilitated the healing of gastric injury in rats via the inhibition of pro-inflammatory cytokine production, oxidative stress and neutrophil infiltration as well as the downregulation of COX-2 protein and NF-κB gene expressions.

The impact of cyclooxygenase inhibitor use on urinary prostaglandin metabolites in preterm infants.

BACKGROUND: There is limited evidence on the association between the clinical course of patent ductus arteriosus (PDA) and prostaglandin (PG) metabolites. This study aimed to determine the influence of PDA treatment on urinary PG metabolite excretion in very-low-birth-weight (VLBW) infants. METHODS: Urine samples were collected from 25 VLBW infants at 1, 3, and 7 days of age. Infants were separated into two groups: a PDA-treated group that received a cyclooxygenase-2 (COX) inhibitor (n = 12) and a control group that did not receive a COX inhibitor during the first 7 days after birth (n = 13). Urinary PG metabolite tetranor prostaglandin E2 metabolite (t-PGEM) and tetranor prostaglandin D2 metabolite (t-PGDM) levels were analyzed using liquid chromatography-tandem mass spectrometry. RESULTS: Urinary t-PGEM excretion levels were not significantly different between the groups at 1, 3, and 7 days of age. Urinary t-PGDM excretion levels at 1 day of age were higher in PDA-treated infants than in control infants (median [interquartile range]: 5.5 [2.6, 12.2] versus 2.1 [1.0, 3.9] ng/mg creatinine; p = 0.017); however, among PDA-treated infants, the levels were significantly lower at 3 and 7 days than at 1 day of age (5.5 [2.6, 12.2] versus 3.4 [1.7, 4.5] and 4.0 [1.7, 5.3] ng/mg creatinine, respectively; p < 0.05). The urinary t-PGDM excretion level in the control group did not significantly differ among the time points. CONCLUSION: PDA and COX inhibitor administration affected PG metabolism in VLBW infants. Our results indicated that urinary t-PGDM excretion was significantly associated with PDA-treatment in preterm infants.

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

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

An in vivo drug screen in zebrafish reveals that cyclooxygenase 2-derived prostaglandin D2 promotes spinal cord neurogenesis.

The study of neurogenesis is essential to understanding fundamental developmental processes and for the development of cell replacement therapies for central nervous system disorders. Here, we designed an in vivo drug screening protocol in developing zebrafish to find new molecules and signalling pathways regulating neurogenesis in the ventral spinal cord. This unbiased drug screen revealed that 4 cyclooxygenase (COX) inhibitors reduced the generation of serotonergic interneurons in the developing spinal cord. These results fitted very nicely with available single-cell RNAseq data revealing that floor plate cells show differential expression of 1 of the 2 COX2 zebrafish genes (ptgs2a). Indeed, several selective COX2 inhibitors and two different morpholinos against ptgs2a reduced the number of serotonergic neurons in the ventral spinal cord and led to locomotor deficits. Single-cell RNAseq data and different pharmacological manipulations further revealed that COX2-floor plate-derived prostaglandin D2 promotes neurogenesis in the developing spinal cord by promoting mitotic activity in progenitor cells. Rescue experiments using a phosphodiesterase-4 inhibitor suggest that intracellular changes in cAMP levels underlie the effects of COX inhibitors on neurogenesis and locomotion. Our study provides compelling in vivo evidence showing that prostaglandin signalling promotes neurogenesis in the ventral spinal cord.