Inducible Cyclooxygenase-2 Research Articles

Triterpenoid saponins from Psammosilene tunicoides and their antinociceptive activities

Herein, five undescribed oleanane-type triterpenoid saponins, namely, psammosaponins A–E, along with nine known compounds, were isolated from the roots of Psammosilene tunicoides. Moreover, part of the ethanolic extract of P. tunicoides was acid-hydrolyzed and three aglycones were isolated from the resulting hydrolysate. The structures of all compounds were established through extensive analysis involving 1D and 2D NMR experiments, HRESIMS measurements, chemical derivatization, and comparison of spectroscopic data with the values reported in the literature. In all, 10 of the isolated saponins and the three aglycones were evaluated in the acetic acid-induced writhing model for their antinociceptive activity. At a dose of 40 mg/kg, these compounds exhibited significant inhibitory effects on the mouse writhing response, with inhibitions ranging from 31.9% to 79.3%. In addition, the structure–activity relationships of the isolates were discussed. Among the isolates, quillaic acid 3-O-glucuronide and 16α-hydroxygypsogenic acid showed better antinociceptive activity with inhibitions of 79.3% and 73.7%, respectively. Both isolates also exhibited antinociceptive activities in hot plate and formalin tests on mice. Their antinociceptive mechanism was explored in lipopolysaccharide–stimulated RAW 264.7 cells. These isolates could significantly inhibit the production of nitric oxide and interleukin-6 and downregulate the expression levels of inducible NO synthase, COX-1, and COX-2.

Synthesis of 1-(4-(dimethylamino)phenyl)-3,4-diphenyl-1H-pyrrole-2,5-dione analogues and their anti-inflammatory activities in lipopolysaccharide-induced BV2 cells

A series of thalidomide analogues, where the fused benzene ring in the phthalimide moiety was converted into two separated diphenyl rings in maleimide moiety and N-aminoglutarimide moiety was replaced by substituted phenyl moiety, were synthesized and evaluated for their NO inhibitory activities on BV2 cells stimulated with lipopolysaccharide (LPS). Among the synthesized compounds, the dimethylaminophenyl analogue 1s (IC50 = 7.1 μM) showed significantly higher inhibitory activity than the glutarimide analogue 1a (IC50 > 50 μM) and suppressed NO production dose-dependently without cytotoxicity. In addition, 1s inhibited the production of pro-inflammatory cytokines and the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) by blocking nuclear factor-kappa B (NF-κB) and p38 MAPK pathways. These results demonstrated that 1s showed good anti-inflammatory activity and could become a leading compound for the treatment of neuroinflammatory diseases.

Fucoidan from Sargassum autumnale Inhibits Potential Inflammatory Responses via NF-κB and MAPK Pathway Suppression in Lipopolysaccharide-Induced RAW 264.7 Macrophages.

Fucoidans are sulfate-rich polysaccharides with a wide variety of beneficial biological activities. The present study aimed to highlight the anti-inflammatory activity of fucoidan from the brown seaweed Sargassum autumnale (SA) against lipopolysaccharide (LPS)-induced RAW 264.7 macrophage cells. Among the isolated fucoidan fractions, the third fraction (SAF3) showed a superior protective effect on LPS-stimulated RAW 264.7 cells. SAF3 inhibits nitric oxide (NO) production and expression of prostaglandin E-2 (PGE2) via downregulation of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX2) expression in LPS-induced RAW 26.7 cells. SAF3 treatment decreased pro-inflammatory cytokines IL-1β, TNF-α, and IL-6 expression in LPS-induced cells. LPS stimulation activated NF-κB and MAPK signaling cascades in RAW 264.7 cells, while treatment with SAF3 suppressed them in a concentration-dependent manner. Existing outcomes confirm that SAF3 from S. autumnale possesses potent anti-inflammatory activity and exhibits good potential for application as a functional food ingredient or for the treatment of inflammation-related disorders.

Capnellenes from Capnella imbricata: Deciphering Their Anti-Inflammatory-Associated Chemical Features.

Through our ongoing research on investigating new anti-inflammatory terpenoids derived from soft corals, seven capnellenes sourced from Capnella imbricata were discovered. Among these, three were previously unknown compounds named Δ9(12)-capnellene-6α,8β-diol (1), Δ9(12)-capnellene-6α,8β,10α-triol (2), and Δ9(12)-capnellene-2β,8β,10α-triol (3). The structures of all compounds were determined by spectroscopic analysis (IR, MS, 1D-, and 2D-NMR) and a comparison with the existing literature data. The compounds 1 and 2 were found to be the first-ever identified 6-hydroxy capnellenes. In the inflammation inhibitory assessments, compounds 1-7 were tested for their in vitro activities against inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expressions in LPS-induced RAW264.7 cells. Capnellenes 2 and 5 demonstrated significant reductions in iNOS levels (27.73% and 47.61%) at a concentration of 10 μM. Additionally, capnellenes 1, 5, and 7 (at 10 μM) exhibited statistically significant inhibitions (ranging from 7.64% to 12.57%) against COX-2 protein expressions. Our findings indicated that the oxygen-bearing functionalities at C-8 and C-10 play critical roles in inhibiting iNOS protein induction, which can promote inflammation in LPS-induced RAW264.7 cells. Furthermore, a principal component analysis tool, the chemical global positioning system for natural products (ChemGPS-NP), was applied to confirm these capnellane-based sesquiterpenes as promising candidates for future anti-inflammatory agents targeting iNOS-related targets.

The Effects of 2'-Hydroxy-3,6'-Dimethoxychalcone on Melanogenesis and Inflammation.

In this study, we demonstrated that 2'-hydroxy-3,6'-dimethoxychalcone (3,6'-DMC) alleviated α-MSH-induced melanogenesis and lipopolysaccharides (LPS)-induced inflammation in mouse B16F10 and RAW 264.7 cells. In vitro analysis results showed that the melanin content and intracellular tyrosinase activity were significantly decreased by 3,6'-DMC, without cytotoxicity, via decreases in tyrosinase and the tyrosinase-related protein 1 (TRP-1) and TRP-2 melanogenic proteins, as well as the downregulation of microphthalmia-associated transcription factor (MITF) expression through the upregulation of the phosphorylation of extracellular-signal-regulated kinase (ERK), phosphoinositide 3-kinase (PI3K)/Akt, and glycogen synthase kinase-3β (GSK-3β)/catenin, and downregulation of the phosphorylation of p38, c-Jun N-terminal kinase (JNK), and protein kinase A (PKA). Furthermore, we investigated the effect of 3,6'-DMC on macrophage RAW264.7 cells with LPS stimulation. 3,6'-DMC significantly inhibited LPS-stimulated nitric oxide production. 3,6'-DMC also suppressed the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 on the protein level. In addition, 3,6'-DMC decreased the production of the tumor necrosis factor-α and interleukin-6. Successively, our mechanistic studies revealed that 3,6'-DMC also suppressed the LPS-induced phosphorylation of the inhibitor of IκBα, p38MAPK, ERK, and JNK. The Western blot assay results showed that 3,6'-DMC suppresses LPS-induced p65 translocation from cytosol to the nucleus. Finally, the topical applicability of 3,6'-DMC was tested through primary skin irritation, and it was found that 3,6'-DMC, at 5 and 10 μM concentrations, did not cause any adverse effects. Therefore, 3,6'-DMC may provide a potential candidate for preventing and treating melanogenic and inflammatory skin diseases.

Cervical cancer benefits from trabectedin combination with the β-blocker propranolol: in vitro and ex vivo evaluations in patient-derived organoids.

Background: Cervical cancer (CC) is characterized by genomic alterations in DNA repair genes, which could favor treatment with agents causing DNA double-strand breaks (DSBs), such as trabectedin. Hence, we evaluated the capability of trabectedin to inhibit CC viability and used ovarian cancer (OC) models as a reference. Since chronic stress may promote gynecological cancer and may hinder the efficacy of therapy, we investigated the potential of targeting β-adrenergic receptors with propranolol to enhance trabectedin efficacy and change tumor immunogenicity. Methods: OC cell lines, Caov-3 and SK-OV-3, CC cell lines, HeLa and OV2008, and patient-derived organoids were used as study models. MTT and 3D cell viability assays were used for drug(s) IC50 determination. The analysis of apoptosis, JC-1 mitochondrial membrane depolarization, cell cycle, and protein expression was performed by flow cytometry. Cell target modulation analyses were carried out by gene expression, Western blotting, immunofluorescence, and immunocytochemistry. Results: Trabectedin reduced the proliferation of both CC and OC cell lines and notably of CC patient-derived organoids. Mechanistically, trabectedin caused DNA DSBs and S-phase cell cycle arrest. Despite DNA DSBs, cells failed the formation of nuclear RAD51 foci and underwent apoptosis. Under norepinephrine stimulation, propranolol enhanced trabectedin efficacy, further inducing apoptosis through the involvement of mitochondria, Erk1/2 activation, and the increase of inducible COX-2. Notably, trabectedin and propranolol affected the expression of PD1 in both CC and OC cell lines. Conclusion: Overall, our results show that CC is responsive to trabectedin and provide translational evidence that could benefit CC treatment options. Our study pointed out that combined treatment offset trabectedin resistance caused by β-adrenergic receptor activation in both ovarian and cervical cancer models.

Retracted: PKC-delta and PKD activate MAPK signal pathway in mechano-transcription of colonic smooth muscle cells.

Retraction: [PKC-delta and PKD activate MAPK signal pathway in mechano-transcription of colonic smooth muscle cells, Z. Yang, K. He, T. Wang, et al. Neurogastroenterology & Motility 2023; e14623 (https://onlinelibrary.wiley.com/doi/full/10.1111/nmo.14623)]. The above article, published online on June 6, 2023 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the authors, the Journal Editor in Chief, Maura Corsetti, and John Wiley & Sons Ltd. The retraction has been agreed due to unat[1]tributed overlap between this article and the abstract published in Gastroenterology: Li F, Sarna SK and Shi XP. Roles of PKCs and PKD in Mechanotranscription in Colonic Smooth Muscle Cells: Inhibition of Mechanotranscription as a Potential Treatment for Motility Dysfunction in Obstructive Disorders. In: 2012 Digestive Disease Week Abstract Supplement; May 19-22, San Diego, CA. Abstract 120 (https://www.gastrojournal.org/article/S0016-5085(12)60115-2/pdf).

Myricetin: A Significant Emphasis on Its Anticancer Potential via the Modulation of Inflammation and Signal Transduction Pathways.

Cancer is a major public health concern worldwide and main burden of the healthcare system. Regrettably, most of the currently used cancer treatment approaches such as targeted therapy, chemotherapy, radiotherapy and surgery usually cause adverse complications including hair loss, bone density loss, vomiting, anemia and other complications. However, to overcome these limitations, there is an urgent need to search for the alternative anticancer drugs with better efficacy as well as less adverse complications. Based on the scientific evidences, it is proven that naturally occurring antioxidants present in medicinal plants or their bioactive compounds might constitute a good therapeutic approach in diseases management including cancer. In this regard, myricetin, a polyhydroxy flavonol found in a several types of plants and its role in diseases management as anti-oxidant, anti-inflammatory and hepato-protective has been documented. Moreover, its role in cancer prevention has been noticed through modulation of angiogenesis, inflammation, cell cycle arrest and induction of apoptosis. Furthermore, myricetin plays a significant role in cancer prevention through the inhibition of inflammatory markers such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (Cox-2). Moreover, myricetin increases the chemotherapeutic potential of other anticancer drugs through modulation of cell signaling molecules activity. This review elaborates the information of myricetin role in cancer management through modulating of various cell-signaling molecules based on in vivo and in vitro studies. In addition, synergistic effect with currently used anticancer drugs and approaches to improve bioavailability are described. The evidences collected in this review will help different researchers to comprehend the information about its safety aspects, effective dose for different cancers and implication in clinical trials. Moreover, different challenges need to be focused on engineering different nanoformulations of myricetin to overcome the poor bioavailability, loading capacity, targeted delivery and premature release of this compound. Furthermore, some more derivatives of myricetin need to be synthesized to check their anticancer potential.

Yinma Jiedu Granule attenuates LPS-induced acute lung injury in rats via suppressing inflammation level.

Yinma Jiedu Granule (YMJD) is a traditional Chinese patent medicine (CPM), which has been proved to have anti-inflammatory effects and therapeutical effects on obstructive pulmonary disease. The purpose of the current investigation is to find out if YMJD can alleviate acute lung injury (ALI) induced by lipopolysaccharide (LPS) in rats and its underlying mechanisms. Rats were treated with either vehicle or YMJD for 14 consecutive days, and 2h after the last administration, the rat model of ALI was induced by the intratracheal instillation of LPS. High performance liquid chromatography (HPLC) was applied for the fingerprint analysis of YMJD. The efficacy and molecular mechanisms were investigated. The results showed that treatment with YMJD improved the general state of rats, reduced weight loss and serum lactate (LA) levels, attenuated pulmonary edema and pathological damage of the lung tissue. Moreover, we found that YMJD effectively decreased the infiltration of white blood cells (WBC), lymphocytes (LYM), mononuclear cells (MON) and neutrophils (NEUT) in bronchoalveolar lavage fluid (BALF), reduced the concentration of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) and inhibited inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression in the lung tissue. Additionally, we found that YMJD could significantly increase the activity of superoxide dismutase (SOD) and reduce the malondialdehyde (MDA) level in the lung tissue. By employing RNA-sequencing, we have identified that JAK2/STAT1 is an important pathway that is involved in the lung protection of YMJD, and further Western blot assay verified that YMJD could effectively inhibit the activation of the JAK2/STAT1 pathway. YMJD could attenuate LPS-induced ALI through suppressing inflammation and oxidative stress in the lung tissue of rats, associating with the inhibition of JAK2/STAT1 activation. These findings provide evidence for the clinical use of YMJD for treatment of inflammatory pulmonary diseases like ALI.

Extracellular vesicles from human plasma dampen inflammation and promote tissue repair functions in macrophages.

Although inflammation is a vital defence response to infection, if left uncontrolled, it can lead to pathology. Macrophages are critical players both in driving the inflammatory response and in the subsequent events required for restoring tissue homeostasis. Extracellular vesicles (EVs) are membrane-enclosed structures released by cells that mediate intercellular communication and are present in all biological fluids, including blood. Herein, we show that extracellular vesicles from plasma (pEVs) play a relevant role in the control of inflammation by counteracting PAMP-induced macrophage activation. Indeed, pEV-treatment of macrophages simultaneously with or prior to PAMP exposure reduced the secretion of pro-inflammatory IL-6 and TNF-α and increased IL-10 response. This anti-inflammatory activity was associated with the promotion of tissue-repair functions in macrophages, characterized by augmented efferocytosis and pro-angiogenic capacity, and increased expression of VEGFa, CD300e, RGS2 and CD93, genes involved in cell growth and tissue remodelling. We also show that simultaneous stimulation of macrophages with a PAMP and pEVs promoted COX2 expression and CREB phosphorylation as well as the accumulation of higher concentrations of PGE2 in cell culture supernatants. Remarkably, the anti-inflammatory activity of pEVs was abolished if cells were treated with a pharmacological inhibitor of COX2, indicating that pEV-mediated induction of COX2 is critical for the pEV-mediated inhibition of inflammation. Finally, we show that pEVs added to monocytes prior to their M-CSF-induced differentiation to macrophages increased efferocytosis and diminished pro-inflammatory cytokine responses to PAMP stimulation. In conclusion, our results suggest that pEVs are endogenous homeostatic modulators of macrophages, activating the PGE2/CREB pathway, decreasing the production of inflammatory cytokines and promoting tissue repair functions.

Zeylleucapenoids A-D, Highly Oxygenated Diterpenoids with Anti-Inflammatory Activity from Leucas zeylanica (L.) R. Br.

Four previously undescribed highly oxygenated diterpenoids (1-4), zeylleucapenoids A-D, characterized by halimane and labdane skeletons, were isolated from the aerial parts of Leucas zeylanica. Their structures were elucidated primarily via NMR experiments. The absolute configuration of 1 was established using theoretical ECD calculations and X-ray crystallographic analysis, whereas those for 2-4 were assigned using theoretical ORD calculations. Zeylleucapenoids A-D were tested for anti-inflammatory activity against nitric oxide (NO) production in RAW264.7 macrophages, of which only 4 showed significant efficacy with an IC50 value of 38.45 μM. Further, active compound 4 was also evaluated for the inhibition of the release of pro-inflammatory cytokines TNF-α and IL-6 and was found to have a dose-dependent inhibitory effect, while it showed nontoxic activity for zebrafish embryos. A subsequent Western blotting experiment revealed that 4 inhibited the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Furthermore, molecular docking analysis indicated that the possible mechanism of action for 4 may be bind to targets via hydrogen and hydrophobic bond interactions.

Antioxidant and Anti-Inflammatory Activity on LPS-Stimulated RAW 264.7 Macrophage Cells of White Mulberry (Morus alba L.) Leaf Extracts.

The white mulberry (Morus alba L.) is widely used as a medicinal plant in Asia. In this study, the bioactive compounds of ethanolic extracts of white mulberry leaves from the Sakon Nakhon and Buriram cultivars were evaluated. The ethanolic extracts of mulberry leaves from the Sakon Nakhon cultivar showed the highest total phenolic content of 49.68 mg GAE/g extract and antioxidant activities of 4.38 mg GAE/g extract, 4.53 mg TEAC/g extract, and 92.78 mg FeSO4/g extract using 2,2 diphenyl-1-picrylhydrazyl (DPPH), 2,20-azinobis-(3-ethylbenzothiazolin-6-sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays, respectively. The resveratrol and oxyresveratrol compounds in mulberry leaves were also investigated by high-performance liquid chromatography (HPLC). The mulberry leaf extracts from the Sakon Nakhon and Buriram cultivars showed oxyresveratrol contents of 1.20 ± 0.04 mg/g extract and 0.39 ± 0.02 mg/g extract, respectively, whereas resveratrol was not detected. It was also found that the potent anti-inflammatory properties of mulberry leaf extracts and its compounds, resveratrol and oxyresveratrol, suppressed the LPS-stimulated inflammatory responses in RAW 264.7 macrophage cells by significantly reducing nitric oxide production in a concentration-dependent manner. These compounds further inhibited interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) production and suppressed the mRNA and protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in LPS-stimulated RAW 264.7 macrophage cells. Therefore, it is established that mulberry leaf extract and its bioactive compounds contribute to its anti-inflammatory activity.

Dipterocarpus tuberculatus as a promising anti-obesity treatment in Lep knockout mice.

The therapeutic effects and mechanisms of Dipterocarpus tuberculatus (D. tuberculatus) extracts have been examined concerning inflammation, photoaging, and gastritis; however, their effect on obesity is still being investigated. We administered a methanol extract of D. tuberculatus (MED) orally to Lep knockout (KO) mice for 4 weeks to investigate the therapeutic effects on obesity, weight gain, fat accumulation, lipid metabolism, inflammatory response, and β-oxidation. In Lep KO mice, MED significantly reduced weight gains, food intake, and total cholesterol and glyceride levels. Similar reductions in fat weights and adipocyte sizes were also observed. Furthermore, MED treatment reduced liver weight, lipid droplet numbers, the expressions of adipogenesis and lipogenesis-related genes, and the expressions of lipolysis regulators in liver tissues. Moreover, the iNOS-mediated COX-2 induction pathway, the inflammasome pathway, and inflammatory cytokine levels were reduced, but β-oxidation was increased, in the livers of MED-treated Lep KO mice. The results of this study suggest that MED ameliorates obesity and has considerable potential as an anti-obesity treatment.

CircSLCO3A1 depletion ameliorates lipopolysaccharide-induced inflammation and apoptosis of human pulmonary alveolar epithelial cells through the miR-424-5p/HMGB3 pathway.

Recent studies have shown the pathogenesis of acute lung injury (ALI) involves circular RNA (circRNA). However, there are no data on the role of circSLCO3A1 in ALI and the underlying mechanism. ALI-like cell injury was induced by stimulating human pulmonary alveolar epithelial cells (HPAEpiCs) using lipopolysaccharide (LPS). The expression of circSLCO3A1, miR-424-5p and high mobility group box 3 (HMGB3) was detected by quantitative real-time polymerase chain reaction. Cell viability and cell apoptosis were assessed by cell counting kit-8 (CCK-8) assay and flow cytometry analysis, respectively. Enzyme-linked immunosorbent assay was performed to determine the production of interleukin-1β (IL-1β), IL-6, tumor necrosis factor-α (TNF-α) and monocyte chemotactic protein 1 (MCP-1). Caspase-3 activity was detected by caspase-3 activity assay. Protein expression of inducible NOS (iNOS), cyclooxygenase-2 (COX2), p-p65 and p65 was analyzed by Western blot. The interactions among circSLCO3A1, miR-424-5p and HMGB3 were identified by dual-luciferase reporter assay, RNA immunoprecipitation assay and RNA pull-down assay. CircSLCO3A1 and HMGB3 expression were significantly increased, while miR-424-5p was decreased in LPS-treated HPAEpiCs and the serum of septic ALI patients in comparison with controls. CircSLCO3A1 knockdown assuaged LPS-induced HPAEpiC inflammation and apoptosis. Besides, circSLCO3A1 targeted miR-424-5p and regulated LPS-triggered HPAEpiC inflammation and apoptosis by binding to miR-424-5p. Under the treatment of LPS, miR-424-5p mediated HPAEpiC disorders by targeting HMGB3. Importantly, circSLCO3A1 modulated HMGB3 production by interacting with miR-424-5p. CircSLCO3A1 absence assuaged LPS-induced HPAEpiC inflammation and apoptosis through the miR-424-5p/HMGB3 axis. CircSLCO3A1 expression was upregulated in LPS-induced HPAEpiCs and sepsis-induced ALI patients.CircSLCO3A1 depletion protected against LPS-induced HPAEpiC disorders.CircSLCO3A1 bound to miR-424-5p in HPAEpiCs.MiR-424-5p targeted HMGB3 in HPAEpiCs.CircSLCO3A1 regulated HMGB3 expression through miR-424-5p. The online version contains supplementary material available at 10.1007/s13273-023-00341-6.

The anti-inflammatory effect of ferulic acid is via the modulation of NFκB-TNF-α-IL-6 and STAT1-PIAS1 signaling pathways in 2-methoxyethanol-induced testicular inflammation in rats

BackgroundFerulic acid (FAC) is a component of plant cell walls, where it serves as a building block of lignin and pectin. As such, it is abundantly found in vegetables and other plants. In contrast, 2-methoxyethanol (2METH) is a testicular toxin commonly found in products used by humans. This study is aimed to investigate the effect of FAC on 2METH-induced testicular inflammation in rats. MethodFour groups of 5 animals each were used: Group I served as the control, Group II was exposed to 2METH only (100 mg/kg), Group III was administered 2METH (100 mg/kg) plus FAC (50 mg/kg), and Group IV served as the FAC (50 mg/kg) only group. All administrations were done orally for 30 days. ResultsAt the end of the study, rats administered 2METH only showed a significant increase in the testicular levels of interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-α), inducible nitric oxide synthase (iNOS), cyclooxygenase 2 (COX-2), and nuclear factor κB (NF-κB), as well as RNA gene expressions of Janus kinase 1 (JAK1), signal transducer and activator of transcription 1 (STAT1), and suppressor of cytokine signaling 1 (SOCS1) compared to the control group. In contrast, treatment with FAC led to a significant decrease in the testicular levels of IL-6, TNF-α, iNOS, COX-2, NF-κB, and gene expression of STAT1, while significantly increasing the testicular gene expression of protein inhibitor of activated STAT 1 (PIAS1) compared to rats exposed to 2METH only. ConclusionBased on the data gathered from this study, FAC demonstrated an anti-inflammatory effect by inhibiting the testicular activation of NF-κB through the downregulation of pro-inflammatory markers (IL-6, TNF-α, iNOS, and COX-2) and the inhibition of the STAT1-PIAS1 signaling pathway in rats.

The Effects of 1-O-Acetylbritannilactone Isolated from Inula britannica Flowers on Human Neutrophil Elastase and Inflammation of RAW 264.7 Cells and Zebrafish Larvae.

During a search for natural inflammatory inhibitors, 1-O-acetylbritannilactone (ABL), a sesquiterpene lactone, was isolated from the flowers of Inula britannica. ABL significantly inhibited human neutrophil elastase (HNE) with a half-maximal inhibitory concentration (IC50) of 3.2 ± 0.3 µM, thus did so more effectively than the positive control material (epigallocatechin gallate) (IC50 7.2 ± 0.5 µM). An enzyme kinetic study was performed. ABL noncompetitively inhibited HNE with an inhibition constant Ki of 2.4 µM. ABL inhibited lipopolysaccharide-induced nitric oxide and prostaglandin E2 production by RAW 264.7 cells in a dose-dependent manner, as well as the protein-level expression of inducible nitric oxide synthase and cyclooxygenase-2. The anti-inflammatory effect of ABL was confirmed using a transgenic Tg(mpx:EGFP) zebrafish larval model. The exposure of the larvae to ABL inhibited neutrophil recruitment to the site of injury after tail fin amputation.

Antioxidative and Anti-Inflammatory Activities of Rosebud Extracts of Newly Crossbred Roses.

Oxidative stress and inflammation are basic pathogenic factors involved in tissue injury and pain, as well as acute and chronic diseases. Since long-term uses of synthetic steroids and non-steroidal anti-inflammatory drugs (NSAIDs) cause severe adverse effects, novel effective materials with minimal side effects are required. In this study, polyphenol content and antioxidative activity of rosebud extracts from 24 newly crossbred Korean roses were analyzed. Among them, Pretty Velvet rosebud extract (PVRE) was found to contain high polyphenols and to show in vitro antioxidative and anti-inflammatory activities. In RAW 264.7 cells stimulated with lipopolysaccharide (LPS), PVRE down-regulated mRNA expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and thereby decreased nitric oxide (NO) and prostaglandin E2 (PGE2) production. In a subcutaneous air-pouch inflammation model, treatment with PVRE decreased λ-carrageenan-induced tissue exudation, infiltration of inflammatory cells, and inflammatory cytokines such as tumor necrosis factor-α and interleukin-1β concentrations, as achieved with dexamethasone (a representative steroid). Notably, PVRE also inhibited PGE2, similar to dexamethasone and indomethacin (a representative NSAID). The anti-inflammatory effects of PVRE were confirmed by microscopic findings, attenuating tissue erythema, edema, and inflammatory cell infiltration. These results indicate that PVRE exhibits dual (steroid- and NSAID-like) anti-inflammatory activities by blocking both the iNOS-NO and COX-2-PG pathways, and that PVRE could be a potential candidate as an anti-inflammatory material for diverse tissue injuries.

Anti-Inflammatory Effects of New Naphthyridine from sponge Aaptos suberitoides in LPS-Stimulated RAW 264.7 Macrophages via Regulation of MAPK and Nrf2 Signaling Pathways.

Two new naphthyridine compounds, 4-carbomethoxy-5-keto-1,6-naphthyridine (1) and 4-keto-5-carbomethoxy-1,6-naphthyridine (2) were obtained from the MeOH extracts of sponge Aaptos suberitoides. Their structures were determined by spectroscopic methods, including HR-ESI-MS, 1D-NMR (1H-NMR, 13C-NMR), 2D-NMR (COSY, HSQC, HMBC). The structure of compound 1 was further confirmed via single crystal X-ray diffraction analysis. Compound 1 was found to reduce NO production in LPS-induced RAW 264.7 macrophages with IC50 value of 0.15 mM. In addition, it decreased the mRNA expression levels of pro-inflammatory mediators, such as the tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX2) in LPS-induced macrophages. It also decreased the protein expression of iNOS and COX-2 in LPS-induced macrophages. Mechanistic studies further revealed that compound 1 inhibited the mitogen-activated protein kinase (MAPK), and activated the nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) signaling pathways in LPS-induced RAW 264.7 macrophages.

Interferon-gamma is quintessential for NOS2 and COX2 expression in ER- breast tumors that lead to poor outcome

A strong correlation between NOS2 and COX2 tumor expression and poor clinical outcomes in ER breast cancer has been established. However, the mechanisms of tumor induction of these enzymes are unclear. Analysis of The Cancer Genome Atlas (TCGA) revealed correlations between NOS2 and COX2 expression and Th1 cytokines. Herein, single-cell RNAseq analysis of TNBC cells shows potent NOS2 and COX2 induction by IFNγ combined with IL1β or TNFα. Given that IFNγ is secreted by cytolytic lymphocytes, which improve clinical outcomes, this role of IFNγ presents a dichotomy. To explore this conundrum, tumor NOS2, COX2, and CD8+ T cells were spatially analyzed in aggressive ER–, TNBC, and HER2 + breast tumors. High expression and clustering of NOS2-expressing tumor cells occurred at the tumor/stroma interface in the presence of stroma-restricted CD8+ T cells. High expression and clustering of COX2-expressing tumor cells extended into immune desert regions in the tumor core where CD8+ T cell penetration was limited or absent. Moreover, high NOS2-expressing tumor cells were proximal to areas with increased satellitosis, suggestive of cell clusters with a higher metastatic potential. Further in vitro experiments revealed that IFNγ + IL1β/TNFα increased the elongation and migration of treated tumor cells. This spatial analysis of the tumor microenvironment provides important insight into distinct neighborhoods where stroma-restricted CD8+ T cells exist proximal to NOS2-expressing tumor niches that could have increased metastatic potential.

The immunomodulatory activity of levan in RAW264.7 macrophage varies with its molecular weights

Levan is a fructose homopolymer obtained from both plants and microorganisms. Microbial levan is typically produced in a variety of molecular weights (MW). Previous studies have shown that different MW of levan exhibit different biological activities. Though levan was reported for its immunomodulatory effect by increasing nitric oxide (NO) production in RAW264.7 macrophage cells, whether its MW can affect this activity remains unknown. In this study, the effect of different levan MW from Bacillus subtilis on its immunoregulatory properties was investigated. B. subtilis was cultivated using various cultivation parameters to obtain levan of different MW. Three weight average MW of levan, >8 × 105 Da (M1), 1.5 × 104 Da (M2) and 3.7 × 103 Da (M3), were selected to test for their effect on modulating NO levels in RAW264.7 cells. Our results showed that M2 increased NO production in a dose-dependent manner, and more effectively than that of M1 and M3. Consistent with these findings, M2 significantly stimulated inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX2) protein expression, while less pronounced effects were observed in the cells treated with M1 and M3. Therefore, our results demonstrate that various MW of levan have varying effects on its immunoregulatory activities in RAW264.7 cells. Furthermore, our findings suggest that the size of levan should be taken into account when employing levan as one of the active ingredients in functional foods and immunomodulatory products.