Surf4 collaborates with derlin-2 and derlin-1 to mediate cyclooxygenase-2 translocation to the cytosol for degradation.

Derlin family members participate in the retrotranslocation of endoplasmic reticulum (ER) lumen proteins to the cytosol for ER-associated degradation (ERAD); however, the proteins facilitating this retrotranslocation remain to be explored. Using CRISPR library screening, we have found that derlin-2 and surfeit locus protein 4 (Surf4) are candidates to facilitate degradation of cyclooxygenase-2 (COX-2, also known as PTGS2). Our results show that derlin-2 acts upstream of derlin-1 and that Surf4 acts downstream of derlin-2 and derlin-1 to facilitate COX-2 degradation. Knockdown of derlin-2 or Surf4 impedes the ubiquitylation of COX-2 and the interaction of COX-2 with caveolin-1 (Cav-1) and p97 (also known as VCP) in the cytosol. Additionally, COX-2 degradation is N-glycosylation dependent. Although derlin-2 facilitates degradation of N-glycosylated COX-2, the interaction between derlin-2 and COX-2 is independent of COX-2 N-glycosylation. Derlin-1, Surf4 and p97 preferentially interact with non-glycosylated COX-2, whereas Cav-1 preferentially interacts with N-glycosylated COX-2, regardless of the N-glycosylation pattern. Collectively, our results reveal that Surf4 collaborates with derlin-2 and derlin-1 to mediate COX-2 translocation from the ER lumen to the cytosol. The derlin-2-derlin-1-Surf4-Cav-1 machinery might represent a unique pathway to accelerate COX-2 degradation in ERAD.

Prostaglandin production selectively in brain endothelial cells is both necessary and sufficient for eliciting fever.

Fever is known to be elicited by prostaglandin E2 acting on the brain, but its origin has remained disputed. We show in mice that selective deletion of prostaglandin synthesis in brain endothelial cells, but not in neural cells or myeloid cells, abolished fever induced by intravenous administration of lipopolysaccharide and that selective rescue of prostaglandin synthesis in brain endothelial cells reinstated fever. These data demonstrate that prostaglandin production in brain endothelial cells is both necessary and sufficient for eliciting fever.

The 5-lipoxygenase/cyclooxygenase-2 cross-over metabolite, hemiketal E2, enhances VEGFR2 activation and promotes angiogenesis.

Consecutive oxygenation of arachidonic acid by 5-lipoxygenase and cyclooxygenase-2 yields the hemiketal eicosanoids, HKE2 and HKD2. Hemiketals stimulate angiogenesis by inducing endothelial cell tubulogenesis in culture; however, how this process is regulated has not been determined. Here, we identify vascular endothelial growth factor receptor 2 (VEGFR2) as a mediator of HKE2-induced angiogenesis in vitro and in vivo. We found that HKE2 treatment of human umbilical vein endothelial cells dose-dependently increased the phosphorylation of VEGFR2 and the downstream kinases ERK and Akt that mediated endothelial cell tubulogenesis. In vivo, HKE2 induced the growth of blood vessels into polyacetal sponges implanted in mice. HKE2-mediated effects in vitro and in vivo were blocked by the VEGFR2 inhibitor vatalanib, indicating that the pro-angiogenic effect of HKE2 was mediated by VEGFR2. HKE2 covalently bound and inhibited PTP1B, a protein tyrosine phosphatase that dephosphorylates VEGFR2, thereby providing a possible molecular mechanism for how HKE2 induced pro-angiogenic signaling. In summary, our studies indicate that biosynthetic cross-over of the 5-lipoxygenase and cyclooxygenase-2 pathways gives rise to a potent lipid autacoid that regulates endothelial cell function in vitro and in vivo. These findings suggest that common drugs targeting the arachidonic acid pathway could prove useful in antiangiogenic therapy.

Lonicera japonica Thunb. Ethanol Extract Exerts a Protective Effect on Normal Human Gastric Epithelial Cells by Modulating the Activity of Tumor-Necrosis-Factor-α-Induced Inflammatory Cyclooxygenase 2/Prostaglandin E2 and Matrix Metalloproteinase 9.

Gastric inflammation-related disorders are commonly observed digestive system illnesses characterized by the activation of proinflammatory cytokines, particularly tumor necrosis factor-α (TNF-α). This results in the induction of cyclooxygenase-2 (COX-2)/prostaglandin E2 (PEG2) and matrix metallopeptidase-9 (MMP-9). These factors contribute to the pathogenesis of gastric inflammation disorders. We examined the preventive effects of Lonicera japonica Thunb. ethanol extract (Lj-EtOH) on gastric inflammation induced by TNF-α in normal human gastric mucosa epithelial cells (GES-1). The GES-1 cell line was used to establish a model that simulated the overexpression of COX-2/PGE2 and MMP-9 proteins induced by TNF-α to examine the anti-inflammatory properties of Lj extracts. The results indicated that Lj-EtOH exhibits significant inhibitory effects on COX-2/PEG2 and MMP-9 activity, attenuates cell migration, and provides protection against TNF-α-induced gastric inflammation. The protective effects of Lj-EtOH are associated with the modulation of COX-2/PEG2 and MMP-9 through the activation of TNFR-ERK 1/2 signaling pathways as well as the involvement of c-Fos and nuclear factor kappa B (NF-κB) signaling pathways. Based on our findings, Lj-EtOH exhibits a preventive effect on human gastric epithelial cells. Consequently, it may represent a novel treatment for the management of gastric inflammation.

Pharmacogenomic study of gemcitabine efficacy in patients with metastatic pancreatic cancer: A multicenter, prospective, observational cohort study (GENESECT study).

BACKGROUND: Genetic polymorphisms of molecules are known to cause individual differences in the therapeutic efficacy of anticancer drugs. However, to date, germline mutations (but not somatic mutations) for anticancer drugs have not been adequately studied. The objective of this study was to investigate the association between germline polymorphisms of gemcitabine metabolic and transporter genes with carbohydrate antigen 19-9 (CA 19-9) response (decrease ≥50% from the pretreatment level at 8 weeks) and overall survival (OS) in patients with metastatic pancreatic cancer who receive gemcitabine-based chemotherapy. METHODS: This multicenter, prospective, observational study enrolled patients with metastatic pancreatic cancer patients who were receiving gemcitabine monotherapy or gemcitabine plus nanoparticle albumin-bound paclitaxel combination chemotherapy. Thirteen polymorphisms that may be involved in gemcitabine responsiveness were genotyped, and univariate and multivariate logistic regression analyses were used to determine the association of these genotypes with CA 19-9 response and OS. The significance level was set at 5%. RESULTS: In total, 180 patients from 11 hospitals in Japan were registered, and 159 patients whose CA 19-9 response could be assessed were included in the final analysis. Patients who had a CA 19-9 response had significantly longer OS (372 vs. 241 days; p = .007). RRM1 2464A>G and RRM2 175T>G polymorphisms suggested a weak association with CA 19-9 response and OS, but it was not statistically significant. COX-2 -765G>C polymorphism did not significantly correlate with CA 19-9 response but was significantly associated with OS (hazard ratio, 2.031; p = .019). CONCLUSIONS: Genetic polymorphisms from the pharmacokinetics of gemcitabine did not indicate a significant association with efficacy, but COX-2 polymorphisms involved in tumor cell proliferation might affect OS.

Cyclooxygenase-2/prostaglandin E2 pathway regulates infectious bronchitis virus replication in avian macrophages.

Infectious bronchitis virus (IBV) is a significant respiratory pathogen that affects chickens worldwide. As an avian coronavirus, IBV leads to productive infection in chicken macrophages. However, the effects of IBV infection in macrophages on cyclooxygenase-2 (COX-2) expression are still to be elucidated. Therefore, we investigated the role of IBV infection on the production of COX-2, an enzyme involved in the synthesis of prostaglandin E2 (PGE2) in chicken macrophages. The chicken macrophage cells were infected with two IBV strains, and the cells and culture supernatants were harvested at predetermined time points to measure intracellular and extracellular IBV infection. IBV infection was quantified as has been the COX-2 and PGE2 productions. We found that IBV infection enhances COX-2 production at both mRNA and protein levels in chicken macrophages. When a selective COX-2 antagonist was used to reduce the COX-2 expression in macrophages, we observed that IBV replication decreased. When IBV-infected macrophages were treated with PGE2 receptor (EP2 and EP4) inhibitors, IBV replication was reduced. Upon utilizing a selective COX-2 antagonist to diminish PGE2 expression in macrophages, a discernible decrease in IBV replication was observed. Treatment of IBV-infected macrophages with a PGE2 receptor (EP2) inhibitor resulted in a reduction in IBV replication, whereas the introduction of exogenous PGE2 heightened viral replication. Additionally, pretreatment with a Janus-kinase two antagonist attenuated the inhibitory effect of recombinant chicken interferon (IFN)-γ on viral replication. The evaluation of immune mediators, such as inducible nitric oxide (NO) synthase (iNOS), NO, and interleukin (IL)-6, revealed enhanced expression following IBV infection of macrophages. In response to the inhibition of COX-2 and PGE2 receptors, we observed a reduction in the expressions of iNOS and IL-6 in macrophages, correlating with reduced IBV infection. Overall, IBV infection increased COX-2 and PGE2 production in addition to iNOS, NO, and IL-6 expression in chicken macrophages in a time-dependent manner. Inhibition of the COX-2/PGE2 pathway may lead to increased macrophage defence mechanisms against IBV infection, resulting in a reduction in viral replication and iNOS and IL-6 expressions. Understanding the molecular mechanisms underlying these processes may shed light on potential antiviral targets for controlling IBV infection.

Tumor Homing Chimeric Peptide Rhomboids to Improve Photodynamic Performance by Inhibiting Therapy-Upregulated Cyclooxygenase-2.

Negative therapeutic feedback of inflammation would extensively attenuate the antitumor effect of photodynamic therapy (PDT). In this work, tumor homing chimeric peptide rhomboids (designated as NP-Mel) are fabricated to improve photodynamic performance by inhibiting PDT-upregulated cyclooxygenase-2 (COX-2). The hydrophobic photosensitizer of protoporphyrin IX (PpIX) and palmitic acid are conjugated onto the neuropilin receptors (NRPs) targeting peptide motif (CGNKRTR) to obtain tumor homing chimeric peptide (Palmitic-K(PpIX)CGNKRTR), which can encapsulate the COX-2 inhibitor of meloxicam. The well dispersed NP-Mel not only improves the drug stability and reactive oxygen species (ROS) production ability, but also increase the breast cancer targeted drug delivery to intensify the PDT effect. In vitro and in vivo studies verify that NP-Mel will decrease the secretion of prostaglandin E2 (PGE2) after PDT treatment, inducing the downregulation of IL-6 and TNF-α expressions to suppress PDT induced inflammation. Ultimately, an improved PDT performance of NP-Mel is achieved without inducing obvious systemic toxicity, which might inspire the development of sophisticated nanomedicine in consideration of the feedback induced therapeutic resistance.

Alternative Drug Safety in Children with Nonsteroidal Anti-Inflammatory Drug Hypersensitivity.

INTRODUCTION: Nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently used in the pediatric age group as pain relievers, antipyretics and anti-inflammatory drugs. Since NSAIDs are used in many medical conditions, there is a need for alternative NSAIDs to be used safely in people with hypersensitivity reactions. Selective and partially selective COX-2 inhibitors and weak COX-1 inhibitors are generally used as safe alternative drugs. The aim of this study was to evaluate safe NSAIDs determined by oral provocation tests (OPTs) according to phenotypes in children with NSAID hypersensitivity reactions. METHODS: The results of the oral provocation test performed with alternative NSAIDs (paracetamol, meloxicam, nimesulide, celecoxib) in patients followed up with the diagnosis of NSAID hypersensitivity reaction in the Pediatric Immunology and Allergy Department between January 2015 and February 2023 were evaluated retrospectively. RESULTS: During the study period, 91 patients underwent OPTs with 109 alternative drugs 48 (52.7%) of whom were girls, with a median age of 15 years. 91 patients had a history of reactions to 117 drugs. As an alternative NSAID; OPT was performed with paracetamol in 58 patients, meloxicam in 44 patients, nimesulide in 5 patients, and celecoxib in 2 patients. Since 15 patients used paracetamol safely at home, no tests were performed with paracetamol. Reactions were observed in 3 of the 73 patients (4.1%) who underwent OPT with paracetamol and in 2 of the 44 (4.5%) who underwent OPT with meloxicam. Reactions to nimesulide were also observed in the latter 2 patients (2/5, 40%), but they appeared to tolerate celecoxib. No reaction was observed in the 2 patients who were tested with celecoxib. CONCLUSION: Paracetamol, meloxicam, and nimesulide can be used as safe alternative drugs in most children with NSAID hypersensitivity. Selective COX-2 inhibitors should be tried as an alternative in patients who cannot tolerate them.

Hu'po Anshen decoction promotes fracture healing in mice with traumatic brain injury through BMP2-COX2-ATF4 signaling pathway.

Hu'po Anshen decoction (HPASD), a traditional Chinese medicine used to treat concussion and fracture, could regulate the expression of bone morphogenetic protein 2 (BMP2). However, whether HPASD affects the fracture healing of traumatic brain injury (TBI) combined with a fracture through BMP2 and its downstream signals remains obscure. The chondrocyte-specific BMP2 conditional knockout mice and chondrocyte-specific cyclooxygenase-2 (COX2) overexpression mice were generated. BMP2 conditional knockout mice were treated with fracture surgery, fracture combined with TBI, or fracture combined with TBI followed by different doses of HPASD (2.4, 4.8, and 9.6 g/kg), respectively. TBI was induced by Feeney's weight-drop technique. The fracture callus formation and fracture sites were determined by X-ray, micro-CT, and histological analyses. The expressions of chondrocyte-, osteoblast-, and BMP2/COX2 signal-related targets were determined by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and western blot assays. The specific absence of BMP2 in chondrocytes led to the prolonged formation of cartilage callus, a delay in the osteogenesis initiation and the downregulation of RUNX2, Smad1/5/9, EP4, ERK1/2, RSK2, ATF4. Overexpression of COX2 partially reverses the effects of chondrocyte-specific BMP2 knockout mice. HPASD promoted cartilage callus formation and osteogenesis initiation, as accompanied by upregulated expression levels of RUNX2, Smad1/5/9, EP4, ERK1/2, RSK2, and ATF4 in a time-dependent and concentration-dependent manner in chondrocyte-specific BMP2 knockout mice. Overall, our findings demonstrated that HPASD induced COX2 transcription through the BMP2-Smad1/5/9-RUNX2 axis, and then affected fracture healing through the COX2-mediated EP4-ERK1/2-RSK2-ATF4 axis.

Cyclooxygenase-2 (COX-2)-dependent mechanisms mediate sleep responses to microbial and thermal stimuli.

Prostaglandins (PGs) play a crucial role in sleep regulation, yet the broader physiological context that leads to the activation of the prostaglandin-mediated sleep-promoting system remains elusive. In this study, we explored sleep-inducing mechanisms potentially involving PGs, including microbial, immune and thermal stimuli as well as homeostatic sleep responses induced by short-term sleep deprivation using cyclooxygenase-2 knockout (COX-2 KO) mice and their wild-type littermates (WT). Systemic administration of 0.4 µg lipopolysaccharide (LPS) induced increased non-rapid-eye movement sleep (NREMS) and fever in WT animals, these effects were completely absent in COX-2 KO mice. This finding underscores the essential role of COX-2-dependent prostaglandins in mediating sleep and febrile responses to LPS. In contrast, the sleep and fever responses induced by the pro-inflammatory cytokine tumor necrosis factor α, a proinflammatory cytokine which activates COX-2, were preserved in COX-2 KO animals, indicating that these effects are independent of COX-2-related signaling. Additionally, we examined the impact of ambient temperature on sleep. The sleep-promoting effects of moderate warm ambient temperature were suppressed in COX-2 KO animals, resulting in significantly reduced NREMS at ambient temperatures of 30 °C and 35 °C compared to WT mice. However, rapid-eye-movement sleep responses to moderately cold or warm temperatures did not differ between the two genotypes. Furthermore, 6 h of sleep deprivation induced rebound increases in sleep with no significant differences observed between COX-2 KO and WT mice. This suggests that while COX-2-derived prostaglandins are crucial for the somnogenic effects of increased ambient temperature, the homeostatic responses to sleep loss are COX-2-independent. Overall, the results highlight the critical role of COX-2-derived prostaglandins as mediators of the sleep-wake and thermoregulatory responses to various physiological challenges, including microbial, immune, and thermal stimuli. These findings emphasize the interconnected regulation of body temperature and sleep, with peripheral mechanisms emerging as key players in these integrative processes.

Effects of low-dose acetylsalicylic acid on the inflammatory response to experimental sleep restriction in healthy humans.

BACKGROUND: Sleep deficiencies, such as manifested in short sleep duration or insomnia symptoms, are known to increase the risk for multiple disease conditions involving immunopathology. Inflammation is hypothesized to be a mechanism through which deficient sleep acts as a risk factor for these conditions. Thus, one potential way to mitigate negative health consequences associated with deficient sleep is to target inflammation. Few interventional sleep studies investigated whether improving sleep affects inflammatory processes, but results suggest that complementary approaches may be necessary to target inflammation associated with sleep deficiencies. We investigated whether targeting inflammation through low-dose acetylsalicylic acid (ASA, i.e., aspirin) is able to blunt the inflammatory response to experimental sleep restriction. METHODS: 46 healthy participants (19F/27M, age range 19-63 years) were studied in a double-blind randomized placebo-controlled crossover trial with three protocols each consisting of a 14-day at-home monitoring phase followed by an 11-day (10-night) in-laboratory stay (sleep restriction/ASA, sleep restriction/placebo, control sleep/placebo). In the sleep restriction/ASA condition, participants took low-dose ASA (81 mg/day) daily in the evening (22:00) during the at-home phase and the subsequent in-laboratory stay. In the sleep restriction/placebo and control sleep/placebo conditions, participants took placebo daily. Each in-laboratory stay started with 2 nights with a sleep opportunity of 8 h/night (23:00-07:00) for adaptation and baseline measurements. Under the two sleep restriction conditions, participants were exposed to 5 nights of sleep restricted to a sleep opportunity of 4 h/night (03:00-07:00) followed by 3 nights of recovery sleep with a sleep opportunity of 8 h/night. Under the control sleep condition, participants had a sleep opportunity of 8 h/night throughout the in-laboratory stay. During each in-laboratory stay, participants had 3 days of intensive monitoring (at baseline, 5th day of sleep restriction/control sleep, and 2nd day of recovery sleep). Variables, including pro-inflammatory immune cell function, C-reactive protein (CRP), and actigraphy-estimated measures of sleep, were analyzed using generalized linear mixed models. RESULTS: Low-dose ASA administration reduced the interleukin (IL)-6 expression in LPS-stimulated monocytes (p<0.05 for condition*day) and reduced serum CRP levels (p<0.01 for condition) after 5 nights of sleep restriction compared to placebo administration in the sleep restriction condition. Low-dose ASA also reduced the amount of cyclooxygenase (COX)-1/COX-2 double positive cells among LPS-stimulated monocytes after 2 nights of recovery sleep following 5 nights of sleep restriction compared to placebo (p<0.05 for condition). Low-dose ASA further decreased wake after sleep onset (WASO) and increased sleep efficiency (SE) during the first 2 nights of recovery sleep (p<0.001 for condition and condition*day). Baseline comparisons revealed no differences between conditions for all of the investigated variables (p>0.05 for condition). CONCLUSION: This study shows that inflammatory responses to sleep restriction can be reduced by preemptive administration of low-dose ASA. This finding may open new therapeutic approaches to prevent or control inflammation and its consequences in those experiencing sleep deficiencies. TRIAL REGISTRATION: ClinicalTrials.gov NCT03377543.

Combination Nano-Delivery Systems Remodel the Immunosuppressive Tumor Microenvironment for Metastatic Triple-Negative Breast Cancer Therapy.

Triple-negative breast cancer (TNBC) is an aggressive type of breast cancer for which effective therapies are lacking. Targeted remodeling of the immunosuppressive tumor microenvironment (TME) and activation of the body's immune system to fight tumors with well-designed nanoparticles have emerged as pivotal breakthroughs in tumor treatment. To simultaneously remodel the immunosuppressive TME and trigger immune responses, we designed two potential therapeutic nanodelivery systems to inhibit TNBC. First, the bromodomain-containing protein 4 (BRD4) inhibitor JQ1 and the cyclooxygenase-2 (COX-2) inhibitor celecoxib (CXB) were coloaded into chondroitin sulfate (CS) to obtain CS@JQ1/CXB nanoparticles (NPs). Then, the biomimetic nanosystem MM@P3 was prepared by coating branched polymer poly(ß-amino ester) self-assembled NPs with melittin embedded macrophage membranes (MM). Both in vitro and in vivo, the CS@JQ1/CXB and MM@P3 NPs showed excellent immune activation efficiencies. Combination treatment exhibited synergistic cytotoxicity, antimigration ability, and apoptosis-inducing and immune activation effects on TNBC cells and effectively suppressed tumor growth and metastasis in TNBC tumor-bearing mice by activating the tumor immune response and inhibiting angiogenesis. In summary, this study offers a novel combinatorial immunotherapeutic strategy for the clinical TNBC treatment.

2-(3-(Chloromethyl)benzoyloxy)benzoic Acid reduces prostaglandin E-2 concentration, NOX2 and NFKB expression, ROS production, and COX-2 expression in lipopolysaccharide-induced mice.

INTRODUCTION: Inflammation is a fundamental response to various insults, including microbial invasion and tissue injury. While aspirin (ASA) has been widely used for its anti-inflammatory properties, its adverse effects and limitations highlight the need for novel therapeutic alternatives. Recently, a novel salicylic acid derivative, 2-((3-(chloromethyl)benzoyl)oxy)benzoic acid (3-CH2Cl), has emerged as a potential substitute for ASA, offering a simpler, environmentally friendly synthesis and a promising safety profile. AIM OF THE STUDY: This research aims to evaluate the anti-inflammatory mechanism of 3-CH2Cl in a lipopolysaccharide (LPS)-induced mouse model, focusing on its effects on prostaglandin E-2 (PGE-2) concentration, NOX2 and NFkB expression, ROS production, and COX-2 expression. MATERIAL AND METHODS: Utilizing BALB/C mice subjected to LPS-induced inflammation, we investigated the therapeutic potential of 3-CH2Cl. The study included synthesis and tablet preparation, experimental design, peripheral blood plasma PGE-2 measurement, splenocyte isolation and COX-2 expression analysis, nitric oxide and ROS measurement, and immunohistochemical analysis of NOX2 and NFkB expression. RESULTS: 3-CH2Cl significantly reduced PGE-2 levels (p = 0.005), NO concentration in liver homogenates (p = 0.005) and plasma (p = 0.0011), and expression of NOX2 and NFkB in liver (p < 0.0001) and splenocytes (p = 0.0036), demonstrating superior anti-inflammatory activity compared to ASA. Additionally, it showed potential in decreasing COX-2 expression in splenocytes. CONCLUSION: 3-CH2Cl exhibits potent anti-inflammatory properties, outperforming ASA in several key inflammatory markers in an LPS-induced inflammation model. The reduction of COX-2 expression, alongside the reduction of pro-inflammatory cytokines and oxidative stress markers, suggest it as a promising therapeutic agent for various inflammatory conditions.

Novel anti-cancer effect of 2-arachidonoylglycerol via processing body formation in HCA-7 human colon cancer cells.

The endocannabinoid 2-arachidonoylglycerol (2-AG) has been reported to exhibit anticancer effects, including against colorectal cancer (CRC); however, the detailed mechanisms have not been clarified. Herein, we demonstrated that 2-AG suppressed cyclooxygenase-2 (COX-2) expression induced by prostaglandin E2 in human colon cancer HCA-7 cells. The suppression of COX-2 expression by 2-AG was through the acceleration of processing body (P-body) formation followed by COX-2 mRNA degradation. These effects were restored by TAK-715, a specific inhibitor of p38 MAPK. Therefore, the effect of 2-AG on COX-2 may be distinct from conventional non-steroidal anti-inflammatory drugs (NSAIDs). NSAIDs inhibit the function of COX-2, whereas 2-AG suppresses the protein expression of COX-2. Recently, the cardiovascular risks of NSAIDs were reported by the Food and Drug Administration in the United States. Therefore, elucidation of the effect of 2-AG is expected to contribute to the development of an alternative and novel therapeutic option that would have no or fewer risks regarding cardiovascular events.

Explainable artificial intelligence-assisted virtual screening and bioinformatics approaches for effective bioactivity prediction of phenolic cyclooxygenase-2 (COX-2) inhibitors using PubChem molecular fingerprints.

Cyclooxygenase-2 (COX-2) inhibitors are nonsteroidal anti-inflammatory drugs that treat inflammation, pain and fever. This study determined the interaction mechanisms of COX-2 inhibitors and the molecular properties needed to design new drug candidates. Using machine learning and explainable AI methods, the inhibition activity of 1488 molecules was modelled, and essential properties were identified. These properties included aromatic rings, nitrogen-containing functional groups and aliphatic hydrocarbons. They affected the water solubility, hydrophobicity and binding affinity of COX-2 inhibitors. The binding mode, stability and ADME properties of 16 ligands bound to the Cyclooxygenase active site of COX-2 were investigated by molecular docking, molecular dynamics simulation and MM-GBSA analysis. The results showed that ligand 339,222 was the most stable and effective COX-2 inhibitor. It inhibited prostaglandin synthesis by disrupting the protein conformation of COX-2. It had good ADME properties and high clinical potential. This study demonstrated the potential of machine learning and bioinformatics methods in discovering COX-2 inhibitors.

Effect of theanine on the hyperexcitability of trigeminal secondary nociceptive neurons following orofacial inflammation in rats.

The present in vivo study investigated whether systemic administration of theanine attenuates the inflammation-induced hyperexcitability of trigeminal spinal nucleus caudalis (SpVc) neurons associated with hyperalgesia. Complete Freund's adjuvant (CFA) was injected into the whisker pads of 24 rats to induce inflammation, and then mechanical stimulation was applied to the orofacial area to assess the threshold of escape. The mechanical threshold was statistically significantly lower in CFA-inflamed rats compared to uninjected naïve rats, and this lowered threshold returned to control levels after 2 days of theanine administration. The mean discharge frequency of SpVc wide-dynamic range (WDR) neurons to mechanical stimuli in anesthetized CFA-inflamed rats was statistically significantly lower after two days of theanine administration. In addition, the increased mean spontaneous discharge of SpVc WDR neurons in CFA-inflamed rats statistically significantly decreased after theanine administration. Similarly, theanine restored the expanded mean receptive field size in CFA-inflamed rats to control levels. Taken together, these results suggest that administration of theanine attenuates inflammatory hyperalgesia associated with hyperexcitability of nociceptive SpVc WDR neurons. These findings support the potential of theanine as a therapeutic agent in complementary alternative medicine strategies to prevent inflammatory hyperalgesia.

Target-guided isolation and purification of cyclooxygenase-2 inhibitors from Meconopsis integrifolia (Maxim.) Franch. by high-speed counter-current chromatography combined with ultrafiltration liquid chromatography.

Meconopsis integrifolia (Maxim.) Franch. is used extensively in traditional Tibetan medicine for its potent anti-inflammatory properties. In this study, six cyclooxygenase-2 (COX-2) inhibitors were purified from M. integrifolia using high-speed counter-current chromatography guided by ultrafiltration liquid chromatography (ultrafiltration-LC). First, ultrafiltration-LC was performed to profile the COX-2 inhibitors in M. integrifolia. The reflux extraction conditions were further optimized using response surface methodology, and the results showed that the targeted COX-2 inhibitors could be well enriched under the optimized extraction conditions. Then the six target COX-2 inhibitors were separated by high-speed countercurrent chromatography with a solvent system composed of ethyl acetate/n-butanol/water (4:1:4, v/v/v. Finally, the six COX-2 inhibitors, including 21.2 mg of 8-hydroxyluteolin 7-sophoroside, 29.6 mg of 8-hydroxyluteolin 7-[6'''-acetylallosyl-(1→2)-glucoside], 42.5 mg of Sinocrassoside D3, 54.1 mg of Hypolaetin 7-[6'''-acetylallosyll-(l→2)-3''-acetylglucoside, 30.6 mg of Hypolaetin 7-[6'''-acetylallosyll-(l→2)-6''-acetylglucoside and 17.8 mg of Hypolaetin were obtained from 500 mg of sample. Their structures were elucidated by 1 H-NMR spectroscopy. This study reveals that ultrafiltration-LC combined with high-speed counter-current chromatography is a robust and efficient strategy for target-guided isolation and purification of bioactive molecules. It also enhances the scientific understanding of the anti-inflammatory properties of M. integrifolia but also paves the way for its further medicinal applications.

Changes in nerve growth factor in vastus lateralis muscle after the first versus second bout of one-leg eccentric cycling.

Delayed onset muscle soreness (DOMS) develops after performing unaccustomed eccentric exercises. Animal studies have shown that DOMS is mechanical hyperalgesia through nociceptor sensitization induced by nerve growth factor (NGF) and glial cell line-derived neurotrophic factor (GDNF) upregulated by cyclooxygenase-2 (COX-2). However, no previous study has investigated these in relation to DOMS in humans. This study compared the first and second bouts of one-leg eccentric cycling (ECC) for changes in NGF, GDNF, and COX-2 mRNA in the vastus lateralis (VL). Seven healthy adults (18-40 years) performed two bouts of ECC (10 sets of 50 contractions) with 80% maximal voluntary concentric peak torque separated by 2 weeks (ECC1, ECC2). Muscle soreness that was assessed by a visual analog scale and maximal voluntary isometric contraction (MVC) torque of the knee extensors were measured before, immediately after (MVC only), 24 and 48 h post-exercise. Muscle biopsy was taken from the VL before the first bout from nonexercised leg (control) and 24 h after each bout from the exercised leg, and analyzed for NGF, GDNF, and COX-2 mRNA. Peak DOMS was more than two times greater and MVC torque at 48 h post-exercise was approximately 20% smaller after ECC1 than ECC2 (p < 0.05), suggesting the repeated bout effect. NGF mRNA level was higher (p < 0.05) post-ECC1 (0.79 ± 0.68 arbitrary unit) than control (0.06 ± 0.07) and post-ECC2 (0.08 ± 0.10). GDNF and COX-2 mRNA did not show significant differences between control, post-ECC1, and post-ECC2. These results suggest that an increase in NGF is associated with the development of DOMS in humans.

Assessment of the effect of sodium tetraborate on oxidative stress, inflammation, and apoptosis in lead-induced nephrotoxicity.

Exposure to Pb, a toxic heavy metal, is a risk factor for renal damage. Borax, an essential trace element in cellular metabolism, is a naturally occurring compound found in many foods. This study investigated the effects of sodium tetraborate (ST), a source of borax, on renal oxidative stress and inflammation in rats exposed to Pb. Wistar Albino rats (n = 24) were divided into four groups: Control (0.5 mL, i.p. isotonic), Pb (50 mg/kg/day/i.p.), ST (4.0 mg/kg/day/oral), and Pb + ST groups. At the end of the five-day experimental period, kidney tissue samples were obtained and analyzed. Histopathologically, the Pb-induced damage observed in the Pb group improved in the Pb + ST group. Immunohistochemically, Pb administration increased the expression of inducible nitric oxide synthase, cyclooxygenase-2, and caspase-3. When evaluated biochemically, Pb application inhibited catalase and glutathione peroxidase (GSH-Px) enzyme activities and activated superoxide dismutase enzyme activity. An increase in malondialdehyde levels was considered an indicator of damage. ST application increases glutathione peroxidase enzyme activity and decreased malondialdehyde levels. These results indicate that ST might play a protective role against Pb-induced renal damage via the upregulation of renal tissue antioxidants and cyclooxygenase-2, inducible nitric oxide synthase, and caspase-3 immunoexpression.

Benzothiazole derivatives in the design of antitumor agents.

Benzothiazoles are a class of heterocycles with multiple applications as anticancer, antibiotic, antiviral, and anti-inflammatory agents. Benzothiazole is a privileged scaffold in drug discovery programs for modulating a variety of biological functions. This review focuses on the design and synthesis of new benzothiazole derivatives targeting hypoxic tumors. Cancer is a major health problem, being among the leading causes of death. Tumor-hypoxic areas promote proliferation, malignancy, and resistance to drug treatment, leading to the dysregulation of key signaling pathways that involve drug targets such as vascular endothelial growth factor, epidermal growth factor receptor, hepatocyte growth factor receptor, dual-specificity protein kinase, cyclin-dependent protein kinases, casein kinase 2, Rho-related coil formation protein kinase, tunica interna endothelial cell kinase, cyclooxygenase-2, adenosine kinase, lysophosphatidic acid acyltransferases, stearoyl-CoA desaturase, peroxisome proliferator-activated receptors, thioredoxin, heat shock proteins, and carbonic anhydrase IX/XII. In turn, they regulate angiogenesis, proliferation, differentiation, and cell survival, controlling the cell cycle, inflammation, the immune system, and metabolic alterations. A wide diversity of benzothiazoles were reported over the last years to interfere with various proteins involved in tumorigenesis and, more specifically, in hypoxic tumors. Many hypoxic targets are overexpressed as a result of the hypoxia-inducible factor activation cascade and may not be present in normal tissues, providing a potential strategy for selectively targeting hypoxic cancers.