Inhibition Of Cyclooxygenase-2 Expression Research Articles

MiR-26b Mimic Inhibits Glioma Proliferation In Vitro and In Vivo Suppressing COX-2 Expression.

Glioma is the most common malignant tumor of the nervous system. Studies have shown the microRNA-26b (miR-26b)/cyclooxygenase-2 (COX-2) axis in the development and progression in many tumor cells. Our study aims to investigate the effect and mechanism of the miR-26b/COX-2 axis in glioma. Decreased expression of miR-26b with increased levels of COX-2 was found in glioma tissues compared with matched normal tissues. A strong negative correlation was observed between the level of miR-26b and COX-2 in 30 glioma tissues. The miR-26b was then overexpressed by transfecting a miR-26b mimic into U-373 cells. The invasive cell number and wound closing rate were reduced in U-373 cells transfected with miR-26b mimic. In addition, COX-2 siRNA enhanced the effect of miR-26b mimic in suppressing the expression of p-ERK1 and p-JNK. Finally, the in vivo experiment revealed that miR-26b mimic transfection strongly reduced the tumor growth, tumor volume, and expression of matrix metalloproteinase-2 (MMP-2) and MMP-9. Taken together, our research indicated a miR-26b/COX-2/ERK/JNK axis in regulating the motility of glioma in vitro and in vivo, providing a new sight for the treatment of glioma.

The Inhibition of Ethanol Extract of Phaleria macrocarpa Stem Bark on COX-2 Expression of HCT116 Colorectal Cancer Cell Line

Objective of this research to determine the inhibition of ethanol extract of Phaleria macrocarpa Boerl. stem bark on COX-2 expression in colorectal cancer cell line HCT116. Ethanol extract of Phaleria macrocarpa stem bark was prepared for maceration in ethanol. Phaleria macrocarpa stem bark in-vitro anticancer activity was tested with MTT assay on HCT116 colorectal cancer cell line. This study also assessed the effect of ethanol extract of Phaleria macrocarpa stem bark on the inhibition of COX-2 expression in the HCT116 colorectal cancer cell line by counting the H-score from immunocytochemistry staining with help from ImageJ and TMARKER application. Ethanol extract of Phaleria macrocarpa stem bark shows anticancer activity by inhibiting its growth with IC50 of 1, 327 μg/ml. One of the pathways is through inhibition of COX-2 expression, shown by the H-score of 173, 33 after administration of Phaleria macrocarpa stem bark at a dose of 200 ppm. This study shows that Phaleria macrocarpa stem bark is a colorectal cancer growth inhibitor, one of which is through inhibition of COX-2.

Upregulation of PPAR-gamma activity inhibits cyclooxygenase 2 expression in cortical neurons with N-methyl-d-aspartic acid induced excitatory neurotoxicity

This study aimed to investigate the effect of upregulated peroxisome proliferator-activated receptor-gamma (PPAR-γ) activity on cyclooxygenase 2 (COX-2) expression and N-methyl-d-aspartic acid (NMDA)-induced excitatory neurotoxicity in primary cultured cortical neurons. Rat cortical neurons were cultured for 8 days in vitro, and divided into control, NMDA, MK-801 (selective NMDA antagonist), rosiglitazone (ROSI, PPAR-γ agonist), GW9662 (PPAR-γ antagonist), NS398 (selective COX-2 antagonist) and NS398 + ROSI groups. Two hours after treatment in each group, cell viability, intracellular Ca2+ concentrations, PPAR-γ and COX-2 protein expression were detected by CCK-8 assay, flow cytometry and western blot assay, respectively. The results showed that compared with the control group, 100 μmol/L of NMDA significantly decreased the neuronal cell viability, increased Ca2+ concentrations, which also increased the COX-2 protein expression and decreased PPAR-γ expression in neurons. Compared with the NMDA group, the cell viability was increased, Ca2+ concentrations and COX-2 protein expression were significantly decreased, PPAR-γ expression was significantly increased in the MK-801, ROSI, NS398 and ROSI + NS398 groups (both P < 0.01). This finding suggested that upregulation of PPAR-γ activity can inhibit COX-2 expression, decrease Ca2+ concentrations in primary cultured cortical neurons, and protect neurons against NMDA-induced excitatory neurotoxicity.

Anti-inflammatory effect of Chunkoongkeigi-tang on IL-1β-induced inflamed A549 by the inhibition of COX-2 expression

Inflammatory lung disease can arise due to the immoderate expression of pro-inflammatory genes and the disharmony of complex cytokines. Chunkoongkeigi-tang (CKT) has been prescribed to patients with asthmatic symptoms in herbal medicine clinics. However, the effects of CKT on the inflamed human lung cell line A549 have yet to be revealed. Thus we investigate whether CKT can suppress inflammatory response on interleukin 1β (IL-1β)-induced inflamed A549. In an effort to understand the inhibitory activity of CKT on inflamed A549, we use IL-1β to induce inflammatory gene COX-2 expressions on A549. Inhibition of COX-2 expression and inflammatory cytokine secretion through blocking mitogen activated protein kinase (MAPK) pathway and transcriptional nuclear factor kappa B (NF-κB) activity was confimed by western blot and real-time PCR. Compounds in CKT were identified by liquid chromatography-mass spectrometry (LC-MS). CKT inhibited increased COX-2 in an IL-1β-induced inflammatory state of A549. We confirmed that CKT regulated the mitogen activated protein kinase (MAPK) pathway and transcriptional nuclear factor kappa B (NF-κB). Additionally, a suppressive effect of CKT on the mRNA expression levels of cytokine-related asthma ((IL-5, IL-6, IL-17 and TNF-α) was noted in IL-1β-induced inflamed A549. According to LC-MS analysis, we identified several components in CKT which can be expected to be the active compounds of the anti-inflammatory effect of CKT. We verify the anti-inflammatory effect of CKT via the reduction of the IL-1β-induced increased COX-2 expression through the MAPK and NF-κB pathways, suggesting useful anti-asthmatic potential by inhibiting inflammatory cytokines, especially in patients with asthma.

(±) Gancochlearols A and B: cytotoxic and COX-2 inhibitory meroterpenoids from Ganoderma cochlear

(+)- and (−)-gancochlearols A (1) and B (2), two pairs of dimeric mertoterpenoid enantiomers were isolated from the fruiting bodies of Ganoderma cochlear. Their structures were identified by spectroscopic methods. Biological assessments show that the enantiomers of 1 and 2 are cytotoxic against three human cancer cell lines (A549, K562, Huh-7) and could inhibit COX-2 expression with IC50 values less than 10 μM.

Ginsenoside Rf inhibits cyclooxygenase-2 induction via peroxisome proliferator–activated receptor gamma in A549 cells

BackgroundGinsenoside Rf is a ginseng saponin found only in Panax ginseng that affects lipid metabolism. It also has neuroprotective and antiinflammatory properties. We previously showed that Korean Red Ginseng (KRG) inhibited the expression of cyclooxygenase-2 (COX-2) by hypoxia via peroxisome proliferator–activated receptor gamma (PPARγ). The aim of the current study was to evaluate the possibility of ginsenoside Rf as an active ingredient of KRG in the inhibition of hypoxia-induced COX-2 via PPARγ. MethodsThe effects of ginsenoside Rf on the upregulation of COX-2 by hypoxia and its antimigration effects were evaluated in A549 cells. Docking of ginsenoside Rf was performed with the PPARγ structure using Surflex-Dock in Sybyl-X 2.1.1. ResultsPPARγ protein levels and peroxisome proliferator response element promoter activities were promoted by ginsenoside Rf. Inhibition of COX-2 expression by ginsenoside Rf was blocked by the PPARγ-specific inhibitor, T0070907. The PPARγ inhibitor also blocked the ability of ginsenoside Rf to suppress cell migration under hypoxia. The docking simulation results indicate that ginsenoside Rf binds to the active site of PPARγ. ConclusionsOur results demonstrate that ginsenoside Rf inhibits hypoxia induced-COX-2 expression and cellular migration, which are dependent on PPARγ activation. These results suggest that ginsenoside Rf has an antiinflammatory effect under hypoxic conditions. Moreover, docking analysis of ginsenoside Rf into the active site of PPARγ suggests that the compound binds to PPARγ in a position similar to that of known agonists.

Effect of thiol antioxidants on lipopolysaccharide-induced cyclooxygenase-2 expression in pulmonary epithelial cells.

Cyclooxygenase-2 (COX-2) plays an important role in pulmonary inflammatory response, and its expression is regulated by several transcription factors including nuclear factor kappa-B (NF-κB), activator protein-1 (AP-1), and signal transducer and activator of transcription-3 (STAT-3), which are activated by oxidative stress. Glutathione (GSH) and N-acetyl cysteine (NAC) are thiol antioxidants that scavenge reactive oxygen species (ROS). The present study investigated whether lipopolysaccharide (LPS) induces COX-2 expression through ROS generation and the activation of oxidant-sensitive transcription factors such as NF-κB, AP-1, and STAT-3 in pulmonary epithelial A549 cells. The cells were pretreated with GSH or NAC for 1 hour prior to LPS stimulation. Intracellular ROS levels, DNA-binding activities of NF-κB, AP-1, and STAT-3, and mRNA and protein levels of COX-2 were determined. Our results showed that LPS increased ROS levels that peaked at 2 hours. LPS activated NF-κB, AP-1, and STAT-3 and induced the expression of COX-2 in A549 cells in a time-dependent manner. Pretreatment of thiol antioxidants GSH and NAC reduced ROS levels and attenuated the increase in ROS, the activation of NF-κB, AP-1, and STAT-3, and the expression of COX-2 in LPS-treated A549 cells. In conclusion, GSH and NAC suppress COX-2 expression by reducing ROS levels and inhibiting the activation of NF-κB, AP-1, and STAT-3 in pulmonary epithelial A549 cells exposed to LPS. Pretreatment with thiol antioxidants GSH and NAC may be beneficial for the treatment of pulmonary inflammation associated with oxidative stress.

Coffee, but Neither Decaffeinated Coffee nor Caffeine, Elicits Chemoprotection Against a Direct Carcinogen in the Colon of Wistar Rats

Colorectal cancer (CRC) is the third most frequent malignancy worldwide. Coffee is the second most consumed drink in the globe and suggested to decrease the CRC risk. Here, we explored whether coffee, decaffeinated coffee, or caffeine impact on the development of colorectal carcinogenesis induced by the direct carcinogen N-methyl-N-nitro-N-nitrosoguanidine (MNNG) in rats. To this end, sixty-four young male Wistar rats were divided into eight groups of eight animals each. We analyzed the frequency of dysplastic crypts and expression of metallothionein as a biomarker of the cancer risk, as well the expression of phosphorylated H2A histone family/member X (γH2AX) for DNA damage and cyclooxygenase-2 (COX-2) for inflammatory response. We also studied the oxidative stress profile in hepatic and colonic frozen samples (malondialdehyde [MDA], glutathione [GSH], and α-tocopherol). We found that coffee but neither decaffeinated coffee nor caffeine decreased the development of dysplastic crypts in MNNG-exposed rats. All treatments reduced DNA damage intensity in colonocytes. Only decaffeinated coffee increased the numbers of metallothionein positive crypts in comparison with coffee-treated rats. Coffee and caffeine inhibited COX-2 expression in the colon. Both decaffeinated coffee and caffeine decreased hepatic α-tocopherol levels. We suggest that coffee may have other compounds that elicit greater chemoprotective effects than caffeine reducing the CRC risk.

Papain Ameliorates the MPAs Formation-Mediated Activation of Monocytes by Inhibiting Cox-2 Expression via Regulating the MAPKs and PI3K/Akt Signal Pathway.

Monocytes activation and subsequent inflammatory response mediated by monocyte-platelet aggregates (MPAs) formation play the key roles in the early pathogenesis of atherosclerosis (AS). Exploration of novel drugs to ameliorate MPAs formation-mediated monocytes activation would be helpful for the treatment of AS patients. Papain has definite pharmacological effects including antiplatelet, thrombolysis, and anti-inflammation. However, its effect on MPAs formation and the following monocytes activation remains vague. This study aimed to illustrate the underlying mechanisms of papain on MPAs formation-initiated monocytes activation in vitro. In this study, Papain, Cox-2 inhibitor (NS-398), and NF-κB agonist (TNF-α) were used as the treating agents, respectively. MPAs formation and activated monocytes were measured by flow cytometry (FCM). Cox-2 mRNA, MCP-1, and proteins of Cox-2 and NF-κB signal pathway were detected by qRT-PCR, ELISA, and western blotting, respectively. As we observed, papain exhibited the powerful inhibitory effects on thrombin-mediated MPAs formation and monocytes activation in a concentration-dependent manner as what Cox-2 inhibitor demonstrated. However, the inhibitory tendency was significantly reversed by TNF-α. We also discovered that both Cox-2 mRNA and protein expression as well as the release of MCP-1 of monocyte was inhibited by either papain or NS-398, but TNF-α stimulated Cox-2 expression and release of MCP-1. The results of western blotting assay indicated that thrombin-mediated proteins expression of MAPKs and PI3K/Akt signal pathway was inhibited by papain and NS-398. However, TNF-α notably abated the inhibitory effects of papain on the process of MPAs-initiated monocytes activation. Our findings suggest that papain can inhibit the MPAs formation-mediated activation of monocytes by inhibiting the MAPKs and PI3K/Akt signal pathway.

Andrographolide inhibits breast cancer through suppressing COX-2 expression and angiogenesis via inactivation of p300 signaling and VEGF pathway

BackgroundAndrographolide (Andro), a diterpenoid lactone, has been used for treatment of various cancers with less adverse effects. However, the underlying mechanisms regarding its anti-tumor mechanism still remain unclear.MethodsCell viability and proliferation were measured by CCK8 and CFSE dilution assay. The localization of p50/p65 or cytochrome c was determined using confocal immunofluorescence. Streptavidin-agarose pulldown or ChIP assays were used to detect the binding of multiple transactivators to COX-2 promoter. The promoter activity was examined by a dual-Luciferase reporter assay. The functions of Andro on COX-2-mediated angiogenesis were also investigated using human HUVEC cells through tube formation and spheroids sprouting assay. The in vivo anti-tumor efficacy of Andro was analyzed in xenografts nude mice.ResultsThe results indicated that Andro could significantly inhibit the proliferation of human breast cancers, and suppress COX-2 expression at both protein and mRNA levels. Furthermore, Andro could dose-dependently inhibit COX-2-mediated angiogenesis in human endothelial cells. We have also found that Andro significantly promoted the activation of cytochrome c and activated caspase-dependent apoptotic signaling pathway. Our further explorations demonstrated that Andro inhibited the binding of the transactivators CREB2, C-Fos and NF-κB and blocked the recruitment of coactivator p300 to COX-2 promoter. Moreover, Andro could effectively inhibit the activity of p300 histone acetyltransferase (HAT), thereby attenuating the p300-mediated acetylation of NF-κB. Besides, Andro could also dramatically inhibit the migration, invasion and tubulogenesis of HUVECs in vitro. In addition, Andro also exhibited effective anti-tumor efficacy as well as angiogenesis inhibition in vivo.ConclusionIn current study, we explore the potential effects of Andro in suppressing breast cancer growth and tumor angiogenesis, as well as the precise mechanisms. This work demonstrated the potential anti-cancer effects of Andro, indicating that Andro could inhibit COX-2 expression through attenuating p300 HAT activity and suppress angiogenesis via VEGF pathway, and thereby could be developed as an antitumor agent for the treatment of breast cancer.

Radiation quality effects alteration in COX-2 pathway to trigger radiation-induced bystander response in A549 lung carcinoma cells.

This study aimed to determine whether the radiation-induced bystander effect (RIBE) is affected by radiation quality. To mimic the different radiation qualities of the direct action (D)/indirect action (ID) ratio, A549 cells were exposed to X-rays, with either 100 mM of the radical scavenger, thio-urea (TU+), or null (TU–). Biological responses in irradiated and bystander cells were compared at equal lethal effects of a 6% survival dose, which was estimated from the survival curves to be 8 Gy and 5 Gy for TU+ and TU–, respectively. Cyclooxygenase-2 (COX-2) expression in TU– irradiated cells increased up to 8 h post-irradiation, before decreasing towards 24 h. The concentration of prostaglandin E2 (PGE2), a primary product of COX-2 and known as a secreted inducible factor in RIBE, increased over 3-fold compared with that in the control at 8 h post-irradiation. Conversely, COX-2 expression and PGE2 production of TU+ irradiated cells were drastically suppressed. These results show that the larger D/ID suppressed COX-2 expression and PGE2 production in irradiated cells. However, in contrast to the case in the irradiated cells, COX-2 expression was equally observed in the TU– and TU+ co-cultured bystander cells, which showed the highest expression levels at 24 h post-irradiation. Taken together, these findings demonstrate that radiation quality, such as the D/ID ratio, may be an important factor in the alteration of signalling pathways involved in RIBE.

THE INHIBITION OF POLYISOPRENOIDS FROM NYPA FRUTICANS LEAVES ON CYCLOOXYGENASE 2 EXPRESSION OF WIDR COLON CANCER CELLS

Objective: The objective of the study was to investigate the inhibitory activity of polyisoprenoids from Nypa fruticans leaves on the expression of cyclooxygenase 2 (COX-2) against colon cancer cells.Methods: Anticancer activity performed was tested by dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method on colon cancer cell WiDr. The expression of COX-2 was observed by the immunocytochemistry method.Result: Polyisoprenoids from N. fruticans leaves exhibit anticancer activity on WiDr cells through inhibition of COX-2 expression with IC50 180.186±7.16 μg/ml.Conclusions: This study showed that polyisoprenoids from N. fruticans leaves promise chemopreventive agents for colon cancer through COX-2 inhibition.

RGS10 Regulates the Expression of Cyclooxygenase-2 and Tumor Necrosis Factor Alpha through a G Protein-Independent Mechanism.

The small regulator of G protein signaling protein RGS10 is a key regulator of neuroinflammation and ovarian cancer cell survival; however, the mechanism for RGS10 function in these cells is unknown and has not been linked to specific G protein pathways. RGS10 is highly enriched in microglia, and loss of RGS10 expression in microglia amplifies production of the inflammatory cytokine tumor necrosis factor α (TNFα) and enhances microglia-induced neurotoxicity. RGS10 also regulates cell survival and chemoresistance of ovarian cancer cells. Cyclooxygenase-2 (COX-2)-mediated production of prostaglandins such as prostaglandin E2 (PGE2) is a key factor in both neuroinflammation and cancer chemoresistance, suggesting it may be involved in RGS10 function in both cell types, but a connection between RGS10 and COX-2 has not been reported. To address these questions, we completed a mechanistic study to characterize RGS10 regulation of TNFα and COX-2 and to determine if these effects are mediated through a G protein-dependent mechanism. Our data show for the first time that loss of RGS10 expression significantly elevates stimulated COX-2 expression and PGE2 production in microglia. Furthermore, the elevated inflammatory signaling resulting from RGS10 loss was not affected by Gαi inhibition, and a RGS10 mutant that is unable to bind activated G proteins was as effective as wild type in inhibiting TNFα expression. Similarly, suppression of RGS10 in ovarian cancer cells enhanced TNFα and COX-2 expression, and this effect did not require Gi activity. Together, our data strongly indicate that RGS10 inhibits COX-2 expression by a G protein-independent mechanism to regulate inflammatory signaling in microglia and ovarian cancer cells.

Magnolol Inhibits Osteoclast Differentiation via Suppression of RANKL Expression

Magnolol, a compound from the traditional Korean herb Magnolia sp., has been exhaustively investigated as a therapeutic agent against several diseases including systemic and local inflammation. We examined the effects of magnolol on osteoclastic differentiation associated with inflammation. Magnolol markedly reduced interleukin (IL)-1-induced osteoclast formation in co-cultures of murine osteoblasts and bone marrow cells, whereas it had no effect on receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast formation in bone marrow macrophage cultures. In osteoblasts, magnolol markedly inhibited both the up-regulation of RANKL expression and the production of prostaglandin E2 (PGE2) in response to IL-1 treatment. Addition of exogenous PGE2 reversed the inhibitory effects of magnolol on IL-1-induced RANKL expression in osteoblasts and osteoclast formation in co-cultures. Magnolol inhibited IL-1-induced PGE2 production, at least in part by suppressing cyclooxygenase-2 (COX-2) expression. Taken together, these results demonstrate that magnolol inhibits IL-1-induced RANKL expression in osteoblasts through suppression of COX-2 expression and PGE2 production, resulting in inhibition of osteoclast differentiation in co-cultures.

Protective Effects of Sinomenine Against Ankylosing Spondylitis and the Underlying Molecular Mechanisms.

BackgroundThis study aimed to investigate the effect and underlying molecular mechanism of sinomenine (SIN) on ankylosing spondylitis (AS).Material/MethodsTo study the potential role of SIN in the pathogenesis of AS, an AS mouse model was established and mice were treated with different concentrations of SIN (10, 30, and 50 mg/kg, administered intraperitoneally). Markers of inflammation and oxidative stress were determined by ELISA assay. Western blot analysis and qRT-PCR were used to quantify the levels of related proteins and gene mRNA expression.ResultsThe results suggest that AS mice has higher levels of TNF-α, IL-1β, and IL-6 (p<0.01 for all), and lower levels of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-PX) (p<0.01 for all). SIN treatment reduced the level of TNF-α, IL-1β, and IL-6 in a dose-dependent manner, and the levels of SOD, CAT, and GSH-PX were dose-dependently increased (p<0.05 for all). The results also revealed that NF-κBp65 expression decreased, while the level of IκB increased, in a dose-dependent manner, after SIN treatment in AS mice (p<0.05 for all). The level of p-p38 was dose-dependently reduced in AS mice by SIN treatment (p<0.05). Moreover, SIN inhibited Cox-2 expression in AS mice in a dose-dependent manner (p<0.05).ConclusionsSIN has a beneficial role in AS through suppressing inflammatory mediators and by down-regulating oxidative stress via inhibiting the MAPKp38/NF-κB pathway and Cox-2 expression.

Indole Derivatives as Cyclooxygenase Inhibitors: Synthesis, Biological Evaluation and Docking Studies.

A new series of 2-(5-methoxy-2-methyl-1H-indol-3-yl)-N′-[(E)-(substituted phenyl) methylidene] acetohydrazide derivatives (S1–S18) were synthesized and evaluated for their anti-inflammatory activity, analgesic activity, ulcerogenic activity, lipid peroxidation, ulcer index and cyclooxygenase expression activities. All the synthesized compounds were in good agreement with spectral and elemental analysis. Three synthesized compounds (S3, S7 and S14) have shown significant anti-inflammatory activity as compared to the reference drug indomethacin. Compound S3 was further tested for ulcerogenic index and cyclooxygenase (COX) expression activity. It was selectively inhibiting COX-2 expression and providing the gastric sparing activity. Docking studies have revealed the potential of these compounds to bind with COX-2 enzyme. Compound S3 formed a hydrogen bond between OH of Tyr 355 and NH2 of Arg 120 with carbonyl group and this hydrogen bond was similar to that formed by indomethacin. This study provides insight for compound S3, as a new lead compound as anti-inflammatory agent and selective COX-2 inhibitor.

Fisetin inhibits the generation of inflammatory mediators in interleukin-1β–induced human lung epithelial cells by suppressing the NF-κB and ERK1/2 pathways

Fisetin, a flavone that can be isolated from fruits and vegetables, has anti-tumor and anti-oxidative properties and ameliorates airway hyperresponsiveness in asthmatic mice. This study investigated whether fisetin can suppress the expression of inflammatory mediators and intercellular adhesion molecule 1 (ICAM-1) in A549 human lung epithelial cells that were stimulated with interleukin-1β (IL-1β) to induce inflammatory responses. A549 cells were treated with fisetin (3–30 μM) and then with IL-1β. Fisetin significantly inhibited COX-2 expression and reduced prostaglandin E2 production, and it suppressed the levels of IL-8, CCL5, monocyte chemotactic protein 1, tumor necrosis factor α, and IL-6. Fisetin also significantly attenuated the expression of chemokine and inflammatory cytokine genes and decreased the expression of ICAM-1, which mediates THP-1 monocyte adhesion to inflammatory A549 cells. Fisetin decreased the translocation of nuclear transcription factor kappa-B (NF-κB) subunit p65 into the nucleus and inhibited the phosphorylation of proteins in the ERK1/2 pathway. Co-treatment of IL-1β–stimulated A549 cells with ERK1/2 inhibitors plus fisetin reduced ICAM-1 expression. Furthermore, fisetin significantly increased the effects of the protective antioxidant pathway by promoting the expression of nuclear factor erythroid-2-related factor-2 and heme oxygenase 1. Taken together, these data suggest that fisetin has anti-inflammatory effects and that it suppresses the expression of chemokines, inflammatory cytokines, and ICAM-1 by suppressing the NF-κB and ERK1/2 signaling pathways in IL-1β–stimulated human lung epithelial A549 cells.

Resveratrol inhibits the proliferation of A549 cells by inhibiting the expression of COX-2.

PurposeThe aim was to investigate resveratrol effects on A549 cells proliferation.MethodsA total of 104 lung adenocarcinoma tissues and nontumor tissues were collected. BEAS-2B cells were cultured in RPMI 1640 medium (group A). A549 cells were treated with RPMI 1640 medium containing different resveratrol concentrations. A549 cells were transfected and grouped as follows: blank group, siRNA-negative control group, siRNA-COX-2 group and resveratrol + siRNA-COX-2 group. qRT-PCR and Western blot were conducted to detect COX-2 expression. MTT assay, soft agar clone assay and flow cytometry were performed to assess proliferation and cell cycle.ResultsThe relative expression of COX-2 mRNA was significantly increased in lung adenocarcinoma tissues (P<0.01) and it was closely related with clinical stages. Resveratrol at 60 μmol/L significantly inhibited A549 cells proliferation, S phase cells proportion and COX-2 expression (P<0.01). COX-2 expression in siRNA-COX-2 group was significantly lower than that in blank group and siRNA-negative control group (P<0.01). OD570 values, colony formation rate and S phase cells proportion of resveratrol + siRNA-COX-2 group were much lower than those of other groups (P<0.01).ConclusionResveratrol inhibits A549 cells proliferation by inhibiting COX-2 expression.

Rational drug design and synthesis of new α-Santonin derivatives as potential COX-2 inhibitors

Sesquiterpene compounds are widely known for their numerous pharmacological activities. Herein the focus of the authors was on α-Santonin, a sesquiterpene lactone from the Artemisia genus: the aim was to determine whether α-Santonin could be considered in the treatment of inflammation and pain. To this purpose, a small series of derivatives was designed and screened in silico against the enzyme COX-2 along with the parent compound. Drug-likeness parameters were also assessed. The compounds were eventually synthesized, and few were tested to determine their efficacy in the inhibition of COX-2 activity and expression. Overall, compound A2 was the only one with a detectable inhibitory potential of COX-2 activity whilst two of its ether derivatives demonstrated improved ability in the inhibition of COX-2 expression.

Construction of COX-2 short hairpin RNA expression vector and its inhibitory effect on hepatic fibrosis

ABSTRACTThe aim of this study was to construct recombinant adenovirus vector carrying a short hairpin RNA (shRNA) that can exclusively target cyclooxygenase-2 (COX-2) gene expression and observe its inhibitory effect on hepatic fibrosis. We designed and synthesized three oligonucleotide sequences, and cloned those into a shuttle vector, pYr-1.1-hU6-EGFP, after annealing. The restriction-enzyme digestion and sequencing analyses confirmed that the constructed recombinant eukaryotic expression vector was correct. A recombination reaction using LR Clonase was performed for the pYr-1.1-hU6-EGFP COX-2shRNA and the adenovirus vector pAd/BL-DEST to form Ad-COX-2shRNA. The adenoviruses containing the recombinant plasmids were transfected into hepatic stellate cells (HSCs). The transfection efficiency of the three COX-2 shRNAs exceeded 70%. Reverse transcription PCR (RT-PCR) and western blot confirmed that the target gene expression was decreased at the level of mRNA and protein, and the interference effect of COX-2 shRNA-1 was better than that of the other two COX-2 shRNAs. COX-2 shRNA-1 recombinant adenovirus vectors (1 × 109 PFU/mL) were injected via the tail vein into rats fed a high-fat diet with a 40% carbon tetrachloride peanut oil lavage, which induced liver fibrosis. Rats were euthanized at the end of the 12th week, and their liver was removed. Liver expression of COX-2 mRNA and protein was detected by RT-PCR and immunohistochemistry, respectively. RT-PCR and immunohistochemistry showed that COX-2 shRNA-1 inhibited COX-2 expression in liver tissue. Hematoxylin/eosin and Masson staining showed that COX-2 shRNA-1 ameliorated the severity of liver fibrosis. The COX-2 shRNA eukaryotic expression vectors were constructed successfully and COX-2 shRNA-1 ameliorated liver fibrosis.