Design, synthesis, biological and computational screening of novel pyridine-based thiadiazole derivatives as prospective anti-inflammatory agents.

In this study, a novel series of pyridine-based thiadiazole derivatives (NTD1-NTD5) were synthesized as prospective anti-inflammatory agents by combining substituted carboxylic acid derivatives of 5-substituted-2-amino-1,3,4-thiadiazole with nicotinoyl isothiocyanate in the presence of acetone. The newly synthesized compounds were characterized by FTIR, 1H NMR, 13C NMR, and mass spectrometry. First, the compounds underwent rigorous in vivo testing for acute toxicity and anti-inflammatory activity and the results revealed that three compounds-NTD1, NTD2, and NTD3, displayed no acute toxicity and significant anti-inflammatory activity, surpassing the efficacy of the standard drug, diclofenac. Notably, NTD3, which featured benzoic acid substitution, emerged as the most potent anti-inflammatory agent among the screened compounds. To further validate these findings, an in silico docking study was carried out against COX-2 bound to diclofenac (PDB ID: 1pxx). The computational analysis demonstrated that NTD2, and NTD3, exhibited substantial binding affinity, with the lowest binding energies (-8.5 and -8.4, kcal/mol) compared to diclofenac (-8.4 kcal/mol). This alignment between in vivo and in silico data supported the robust anti-inflammatory potential of these derivatives. Moreover, molecular dynamics simulations were conducted, extending over 100 ns, to examine the dynamic interactions between the ligands and the target protein. The results solidified NTD3's position as a leading candidate, showing potent inhibitory activity through strong and sustained interactions, including stable hydrogen bond formations. This was further confirmed by RMSD values of 2-2.5 Å and 2-3Ǻ, reinforcing NTD3's potential as a useful anti-inflammatory agent. The drug likeness analysis of NTD3 through SwissADME indicated that most of the predicted parameters including Lipinski rule were within acceptable limits. While these findings are promising, further research is necessary to elucidate the precise relationships between the chemical structures and their activity, as well as to understand the mechanisms underlying their pharmacological effects. This study lays the foundation for the development of novel anti-inflammatory therapeutics, potentially offering improved efficacy and safety profiles.

Elderly Woman With No Autoimmune Disease With Aseptic Meningitis Caused by Celecoxib.

Nonsteroidal anti-inflammatory drug (NSAID)-induced aseptic meningitis (NIAM) is frequently reported in patients with autoimmune disease. Ibuprofen-induced NIAM is the most common case report of NIAM. We report a patient without autoimmune disease who developed NIAM following oral celecoxib administration. A literature review and survey of cases registered in the Japanese Adverse Drug Event Report (JADER) database is also provided. A 73-year-old woman with no autoimmune disease developed a headache the day after taking celecoxib, and NIAM was suspected. The headache resolved quickly following celecoxib discontinuation. Although lumbar puncture was not available in this case, bacterial or viral meningitis was negative, and NIAM could not be ruled out. This case involved an older adult patient without an autoimmune disease, with celecoxib as the causative NSAID. A literature review found numerous cases of autoimmune diseases in younger patients. To date, only one case of celecoxib-induced NIAM has been reported. Analysis of NIAM cases in JADER revealed an onset time of approximately three days. JADER analysis indicated that NIAM tended to occur immediately after administration, although the onset with cyclooxygenase-2 selective agents might be slower.

Rel Family Transcription Factor NFAT5 Upregulates COX2 via HIF-1α Activity in Ishikawa and HEC1a Cells.

Nuclear factor of activated T cells 5 (NFAT5) and cyclooxygenase 2 (COX2; PTGS2) both participate in diverse pathologies including cancer progression. However, the biological role of the NFAT5-COX2 signaling pathway in human endometrial cancer has remained elusive. The present study explored whether NFAT5 is expressed in endometrial tumors and if NFAT5 participates in cancer progression. To gain insights into the underlying mechanisms, NFAT5 protein abundance in endometrial cancer tissue was visualized by immunohistochemistry and endometrial cancer cells (Ishikawa and HEC1a) were transfected with NFAT5 or with an empty plasmid. As a result, NFAT5 expression is more abundant in high-grade than in low-grade endometrial cancer tissue. RNA sequencing analysis of NFAT5 overexpression in Ishikawa cells upregulated 37 genes and downregulated 20 genes. Genes affected included cyclooxygenase 2 and hypoxia inducible factor 1α (HIF1A). NFAT5 transfection and/or treatment with HIF-1α stabilizer exerted a strong stimulating effect on HIF-1α promoter activity as well as COX2 expression level and prostaglandin E2 receptor (PGE2) levels. Our findings suggest that activation of NFAT5-HIF-1α-COX2 axis could promote endometrial cancer progression.

The Effect of Low-Intensity Pulsed Ultrasound on Bone Regeneration and the Expression of Osterix and Cyclooxygenase-2 during Critical-Size Bone Defect Repair.

Low-intensity pulsed ultrasound (LIPUS) is a form of ultrasound that utilizes low-intensity pulsed waves. Its effect on bones that heal by intramembranous ossification has not been sufficiently investigated. In this study, we examined LIPUS and the autologous bone, to determine their effect on the healing of the critical-size bone defect (CSBD) of the rat calvaria. The bone samples underwent histological, histomorphometric and immunohistochemical analyses. Both LIPUS and autologous bone promoted osteogenesis, leading to almost complete closure of the bone defect. On day 30, the bone volume was the highest in the autologous bone group (20.35%), followed by the LIPUS group (19.12%), and the lowest value was in the control group (5.11%). The autologous bone group exhibited the highest intensities of COX-2 (167.7 ± 1.1) and Osx (177.1 ± 0.9) expression on day 30. In the LIPUS group, the highest intensity of COX-2 expression was found on day 7 (169.7 ±1.6) and day 15 (92.7 ± 2.2), while the highest Osx expression was on day 7 (131.9 ± 0.9). In conclusion, this study suggests that LIPUS could represent a viable alternative to autologous bone grafts in repairing bone defects that are ossified by intramembranous ossification.

Ge-gen decoction alleviates primary dysmenorrhoea symptoms in a rat model.

BACKGROUND: Existing treatments for primary dysmenorrhoea (PD), such as NSAIDs, impart side effects. Ge-Gen decoction (GGD), a traditional Chinese medicine, has shown promise in treating PD, but its exact mechanisms remain unclear. Here, we aimed to investigate the efficiency of GGD in alleviating PD using a rat model to understand its precise mechanism of action. METHODS: We established a rat model of dysmenorrhoea induced by oestradiol and oxytocin. The PD rats were administered GGD or Ibuprofen (positive control) intragastrically once daily for seven consecutive days. Serum levels of prostaglandin E2 (PGE2), prostaglandin F2 alpha (PGF2α), ß-endorphin (ß-EP), thromboxane B2 (TXB2), 6-keto-prostaglandin F1α (6-keto-PGF1α) were determined using an enzyme-linked immunosorbent assay (ELISA). The expression levels of oestrogen receptor alpha (ERα) and cyclooxygenase-2 (COX-2) in uterine tissue were measured using immunohistochemical assays, and those of phosphorylated and total extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) were assessed using western blot analysis. RESULTS: Treatment with GGD significantly reduced writhing behaviour, histopathological scores, and levels of COX-2, PGE2, and PGF2α in the serum of PD rats. Additionally, GGD increased ß-EP content and inhibited ERK1/2 activation and ERα expression in uterine tissues. CONCLUSIONS: The results of this study suggest that GGD alleviates PD in rats by suppressing the COX-2-mediated release of PGE2 and PGF2α, modulating the ERα/ERK1/2/COX-2 pathway, and increasing ß-EP content. These results provide insights into the potential mechanisms of GGD in treating PD and support its further investigation as an alternative therapy for this condition.

Ge-Gen decoction is commonly used to alleviate primary dysmenorrhoea. However, its anti-dysmenorrhoea mechanism remains elusive. In this study, using a rat model of primary dysmenorrhoea, we demonstrate that Ge-Gen decoction reduced the levels of cyclooxygenase-2, prostaglandin E2, and prostaglandin F2 alpha in serum and phosphorylated extracellular signal-regulated protein kinases 1 and 2 in the uterus. These results suggest that Ge-Gen decoction alleviates primary dysmenorrhoea via inactivation of the oestrogen receptor alpha/extracellular signal-regulated protein kinases 1 and 2/cyclooxygenase-2 pathway. This study enhances our understanding of the pathogenesis of primary dysmenorrhoea and may potentially inform the development of novel treatment approaches.

Conditionally replicative adenovirus as a therapy for malignant peripheral nerve sheath tumors.

Oncolytic adenoviruses (Ads) stand out as a promising strategy for the targeted infection and lysis of tumor cells, with well-established clinical utility across various malignancies. This study delves into the therapeutic potential of oncolytic Ads in the context of neurofibromatosis type 1 (NF1)-associated malignant peripheral nerve sheath tumors (MPNSTs). Specifically, we evaluate conditionally replicative adenoviruses (CRAds) driven by the cyclooxygenase 2 (COX2) promoter, as selective agents against MPNSTs, demonstrating their preferential targeting of MPNST cells compared with non-malignant Schwann cell control. COX2-driven CRAds, particularly those with modified fiber-knobs exhibit superior binding affinity toward MPNST cells and demonstrate efficient and preferential replication and lysis of MPNST cells, with minimal impact on non-malignant control cells. In vivo experiments involving intratumoral CRAd injections in immunocompromised mice with human MPNST xenografts significantly extend survival and reduce tumor growth rate compared with controls. Moreover, in immunocompetent mouse models with MPNST-like allografts, CRAd injections induce a robust infiltration of CD8+ T cells into the tumor microenvironment (TME), indicating the potential to promote a pro-inflammatory response. These findings underscore oncolytic Ads as promising, selective, and minimally toxic agents for MPNST therapy, warranting further exploration.

Association of COX-2, TNF-α, TLR4, and IKKα With Survival of Patients With Oral Squamous Cell Carcinomas: A Systematic Review.

BACKGROUND: This review investigated the association of COX-2, TNF-α, TLR4, and IKKα with the survival of patients with oral squamous cell carcinoma (SCC). METHODS: A systematic search was conducted in the databases PUBMED, Web of Science, LILACS, EMBASE, Scopus, and Cochrane Library. The studies should assess the expression of those proteins in the tumor and survival outcomes. RESULTS: Twenty-one articles were included. The meta-analysis results leaned towards an association of COX-2 overexpression with a lower overall survival. The estimated hazard ratio was 1.51 (95% CI 0.97, 2.33), but not statistically significant (p=0.07). A low heterogeneity was observed (I2=0%). Regarding TNF-α, TLR4, and IKKα, statistically significant results for the association with survival were presented, but there was not enough data to a meta-analysis. CONCLUSION: COX-2 overexpression may be associated with a poorer prognosis in oral SCC. The insufficiency of studies about TNF-α, TLR4, and IKKα restrained their validation as predictors of prognosis.

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.

Synthesis and In Vitro and Silico Anti-inflammatory Activity of New Thiazolidinedione-quinoline Derivatives.

BACKGROUND: Inflammation is a series of complex defense-related reactions. The inflammation cascade produces various pro-inflammatory mediators. Unregulated production of these pro-inflammatory mediators can lead to a wide range of diseases, including rheumatoid arthritis, sepsis, and inflammatory bowel disease. In the literature, the anti-inflammatory action of quinoline and thiazolidinedione nuclei are well established, alone, and associated with other nuclei. The synthesis of hybrid molecules is a strategy for obtaining more efficient molecules due to the union of pharmacophoric nuclei known to be related to pharmacological activity. OBJECTIVE: Based on this, this work presents the synthesis of thiazolidinedione-quinoline molecular hybrids and their involvement in the modulation of cytokines involved in the inflammatory reaction cascade. METHODS: After synthesis and characterization, the compounds were submitted to cell viability test (MTT), ELISA IFN-γ and TNF-α, adipogenic differentiation, and molecular docking assay with PPARy and COX-2 targets. RESULTS: LPSF/ZKD2 and LPSF/ZKD7 showed a significant decrease in the concentration of IFN- γ and TNF-α, with a dose-dependent behavior. LPSF/ZKD4 at a concentration of 50 µM significantly reduced IL-6 expression. LPSF/ZKD4 demonstrates lipid accumulation with significant differences between the untreated and negative control groups, indicating a relevant agonist action on the PPARγ receptor. Molecular docking showed that all synthesized compounds have good affinity with PPARγ e COX-2, with binding energy close to -10,000 Kcal/mol. CONCLUSION: These results demonstrate that the synthesis of quinoline-thiazolidinedione hybrids may be a useful strategy for obtaining promising candidates for new anti-inflammatory agents.

Relation Between Reactive Oxygen Species Production and Transient Receptor Potential Vanilloid1 Expression in Human Skin During Aging.

Skin sensitivity and impaired epidermal barrier function are associated with aging and are at least partly due to increased production of reactive oxygen species (ROS). Transient receptor potential vanilloid1 (TRPV1) is expressed in keratinocytes, fibroblasts, mast cells, and endothelial cells in skin. We investigated in skin biopsies of adult and elderly donors whether TRPV1 expression is involved in the skin aging process. We found that aging skin showed a strongly reduced epidermal thickness, strongly increased oxidative stress, protease expression, and mast cell degranulation and strongly increased TRPV1 expression both in epidermis and dermis. Based on our findings, the aging-related changes observed in the epidermis of the skin level are associated with increased ROS production, and hypothesized alterations in TRPV1 expression are mechanistically linked to this process.

Hispidulin targets PTGS2 to improve cyclophosphamide-induced cystitis by suppressing NLRP3 inflammasome.

Interstitial cystitis (IC) is a chronic bladder inflammation. Inhibition of prostaglandin G/H synthase 2 (PTGS2) is the most common method for controlling inflammation-related diseases. This study aimed to analyze the effects of hispidulin on the PTGS2 and NOD-like receptor thermal protein domain-associated protein 3 (NLRP3) inflammation in experimental IC models. A binding activity between hispidulin and PTGS2 was measured using molecular docking. Human urothelial cells (SV-HUC-1) were stimulated by 2 ng/mL of interleukin (IL)-1ß for 24 h and cultured in a medium with different concentrations of hispidulin (2.5, 5, 10, 20 µM) for 24 h to observe the expressions of PTGS2 and NLRP3 protein. Cells overexpressing PTGS2 were established by PTGS2 cDNA transfection. In the IL-1ß-treated cells, the NLRP3 inflammasome was measured after 20 µM hispidulin treatment. In rats, animals were performed with three injections of 40 mg/kg cyclophosphamide (CYP) and orally treated with 50 mg/kg/day hispidulin or ibuprofen for 3 days. The bladder pain was measured using Von Frey filaments, and the bladder pathology was observed using hematoxylin and eosin (H&E) staining. The expressions of PTGS2 and NLRP3 inflammasome were also observed in the bladder tissues. A good binding activity was found between hispidulin and PTGS2 (score = - 8.9 kcal/mol). The levels of PTGS2 and NLRP3 inflammasome were decreased with the hispidulin dose increase in the IL-1ß-treated cells (p < 0.05). Cells overexpressing PTGS2 weakened the protective effects of hispidulin in the IL-1ß-treated cells (p < 0.01). In the CYP-treated rats, hispidulin treatment improved the bladder pain through decreasing the nociceptive score (p < 0.01) and suppressed the bladder inflammation through suppressing the expressions of PTGS2 and NLRP3 inflammasome in bladder tissues (p < 0.01). Additionally, the results of ibuprofen treatment were similar to the effects of hispidulin in the CYP-treated rats. This study demonstrates that hispidulin may be a new alternative drug for the IC treatment that binds PTGS2 to perform its functions.

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.

Corrigendum: Pyruvate kinase M2 promotes prostate cancer metastasis through regulating ERK1/2-COX-2 signaling.

[This corrects the article DOI: 10.3389/fonc.2020.544288.].

Renal Expression and Localization of the Receptor for (Pro)renin and Its Ligands in Rodent Models of Diabetes, Metabolic Syndrome, and Age-Dependent Focal and Segmental Glomerulosclerosis.

The (pro)renin receptor ((P)RR), a versatile protein found in various organs, including the kidney, is implicated in cardiometabolic conditions like diabetes, hypertension, and dyslipidemia, potentially contributing to organ damage. Importantly, changes in (pro)renin/(P)RR system localization during renal injury, a critical information base, remain unexplored. This study investigates the expression and topographic localization of the full length (FL)-(P)RR, its ligands (renin and prorenin), and its target cyclooxygenase-2 and found that they are upregulated in three distinct animal models of renal injury. The protein expression of these targets, initially confined to specific tubular renal cell types in control animals, increases in renal injury models, extending to glomerular cells. (P)RR gene expression correlates with protein changes in a genetic model of focal and segmental glomerulosclerosis. However, in diabetic and high-fat-fed mice, (P)RR mRNA levels contradict FL-(P)RR immunoreactivity. Research on diabetic mice kidneys and human podocytes exposed to diabetic glucose levels suggests that this inconsistency may result from disrupted intracellular (P)RR processing, likely due to increased Munc18-1 interacting protein 3. It follows that changes in FL-(P)RR cellular content mechanisms are specific to renal disease etiology, emphasizing the need for consideration in future studies exploring this receptor's involvement in renal damage of different origins.

The neuroprotective potential of curcumin on T. Spiralis infected mice.

BACKGROUND: Trichinella spiralis can affect the brain by inducing inflammatory and vascular changes. Drug management with the antiparasitic drug albendazole can be enhanced by natural compounds such as curcumin. The potential benefit of curcumin as an adjuvant to albendazole in the management of cerebral affection during experimental T. spiralis infection was evaluated. Animals received either curcumin 150 mg/Kg, albendazole 50 mg/Kg or a combination of both drugs. Animal groups receiving treatment were compared with infected and non-infected control groups. Blood levels of reduced glutathione (GSH) and dopamine were measured, and brain tissue expression of cyclooxygenase-2 enzyme (COX-2) and CD34 was assessed by immunohistochemistry. RESULTS: T. spiralis infection resulted in a state of oxidative stress, which was improved by albendazole and curcumin. Also, both drugs restored the peripheral dopamine level, which was decreased in infected non-treated mice. Curcumin was also found to be efficient in improving brain pathology and reducing local COX-2 and CD 34 expression. CONCLUSIONS: Inflammatory and pathological changes during neurotrichinosis can be improved by the addition of curcumin to conventional anti-parasitic drugs.

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.

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.

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.

Silica Nanoparticles Shed Light on Intriguing Cellular Pathways in Human Tracheal Smooth Muscle Cells: Revealing COX-2/PGE2 Production through the EGFR/Pyk2 Signaling Axis.

The use of manufactured silica nanoparticles (SiNPs) has become widespread in everyday life, household products, and various industrial applications. While the harmful effects of crystalline silica on the lungs, known as silicosis or chronic pulmonary diseases, are well understood, the impact of SiNPs on the airway is not fully explored. This study aimed to investigate the potential effects of SiNPs on human tracheal smooth muscle cells (HTSMCs). Our findings revealed that SiNPs induced the expression of cyclooxygenase-2 (COX-2) mRNA/protein and the production of prostaglandin E2 (PGE2) without causing cytotoxicity. This induction was transcription-dependent, as confirmed by cell viability assays and COX-2 luciferase reporter assays. Further analysis, including Western blot with pharmacological inhibitors and siRNA interference, showed the involvement of receptor tyrosine kinase (RTK) EGF receptor (EGFR), non-RTK Pyk2, protein kinase Cα (PKCα), and p42/p44 MAPK in the induction process. Notably, EGFR activation initiated cellular signaling that led to NF-κB p65 phosphorylation and translocation into the cell nucleus, where it bound and stimulated COX-2 gene transcription. The resulting COX-2 protein triggered PGE2 production and secretion into the extracellular space. Our study demonstrated that SiNPs mediate COX-2 up-regulation and PGE2 secretion in HTSMCs through the sequential activation of the EGFR/Pyk2/PKCα/p42/p44MAPKs-dependent NF-κB signaling pathway. Since PGE2 can have both physiological bronchodilatory and anti-inflammatory effects, as well as pathological pro-inflammatory effects, the increased PGE2 production in the airway might act as a protective compensatory mechanism and/or a contributing factor during airway exposure to SiNPs.

Comparative Analysis of Phytochemical Profiles and Selected Biological Activities of Various Morphological Parts of Ligustrum vulgare.

Ligustrum vulgare (LV), widely cultivated in Europe and often used in hedges, has been historically recognized in folk medicine for its potential health benefits. This study focused on exploring the untargeted identification of secondary metabolites in ethanol extracts (70% v/v) from different morphological parts (young shoots, leaves, flowers and fruits) of LV at various stages of plant development, using ultra-high-performance liquid chromatography with high-resolution mass spectrometry (UHPLC-HRMS). Additionally, the selected biological activities (antioxidant activity, cyclooxygenase-2 inhibition (COX-2), α-amylase inhibition and cytotoxicity) of the tested extracts were determined. Untargeted metabolomics showed that LV extracts were a rich source of phenylethanoid compounds, flavonoids, iridoids and their derivatives. The flowers of LV had the highest content of oleuropein (33.43 ± 2.48 mg/g d.w.). The lowest antioxidant activity was obtained for ripe and post-seasonal fruits, while in the case of other samples, the activity was at a similar level. All tested extracts showed α-amylase and COX-2 inhibitory activity. In addition, LV extracts showed strong antiproliferative properties in colorectal (HT29) and liver (HepG2) cancer cell lines. The obtained results show the difference in the content of bioactive compounds in various morphological parts of Ligustrum vulgare. These differences may influence the multifaceted medicinal potential of this plant.