NF-κB Decoy Oligonucleotides Suppress RANTES Expression and Monocyte Chemotactic Activity via NF-κB Inactivation in Stromal Cells of Ectopic Endometrium

Background  The nuclear factor kappa B (NF-κB) pathway is a critical mediator of regulated on activation, normal T cell expressed and secreted (RANTES) gene regulation and therefore represents a potential target for therapy of endometriosis-associated symptoms. Objective  The objective of this study was to investigate the effect of NF-κB decoy oligonucleotides (ODNs) on NF-κB activation, RANTES expression, and monocyte chemotactic activity in ectopic endometrial stromal cells in vitro. Methods  A specific sandwich enzyme-linked immunosorbent assay (ELISA) was used to quantify RANTES expression in ectopic and normal endometrial stromal cells stimulated by interleukin (IL)-1β. Four hours after transfection of NF-κB decoy ODNs, 10 ng/ml IL-1β was added to induce the ectopic endometrial stromal cells to secrete RANTES. The NF-κB activation, RANTES expression, and monocyte chemotactic activity in ectopic endometrial stromal cells were respectively evaluated by electrophoretic mobility shift assay, ELISA, and Boyden chambers. Results  IL-1β induced significantly higher levels (P < 0.05) of RANTES expression in a time-dependent manner in ectopic endometrial stromal cells compared with IL-1β-untreated ectopic and normal endometrial stromal cells. The RANTES accounts for the majority (68%) of the monocyte chemotactic activity in conditioned media of ectopic endometrial stromal cells. In vitro transfection of NF-κB decoy ODNs dramatically decreased (P < 0.05) the NF-κB activation, RANTES expression, and monocyte chemotactic activity in IL-1β-induced ectopic endometrial stromal cells. Conclusions  NF-κB decoy ODNs may exert anti-inflammatory effects in ectopic endometrial stromal cells via the suppression of NF-κB activation, RANTES expression, and monocyte chemotactic activity.     

Saturated Fatty Acids Up-regulate COX-2 Expression in Prostate Epithelial Cells via Toll-like Receptor 4/NF-κB Signaling

Cyclooxygenase-2 (COX-2) has been implicated in prostate carcinogenesis, and recently it has been confirmed to be a molecular target of saturated fatty acids (SFAs). In the present study, we investigated the effect of stearic acid (SA) and palmitic acid (PA), two of the most abundant SFAs contained in dietary fat, on COX-2 expression in prostate epithelial cells and the signaling transduction pathway involved. First, we demonstrated that both SA and PA increased the mRNA and protein expression of COX-2, and consistently induced the activation of NF-κB in RWPE-1, BPH-1 and PC-3 prostate epithelial cell lines. The effect of SA and PA on COX-2 over-expression and NF-κB activation was in a dose-dependent manner, and PA was more potent than SA at the same concentration. Then, we demonstrated inhibition of NF-κB using its specific inhibitor strikingly attenuated PA-induced COX-2 expression. Toll-like receptor 4 (TLR4) was revealed to be expressed on RWPE-1, BPH-1 and PC-3 cell lines by PCR and immunofluorescence staining, and blocking its signaling significantly inhibited PA induced COX-2 over-expression and NF-κB activation. Taken together, we demonstrated that SFAs can up-regulate COX-2 expression in prostate epithelial cells, and this effect was mediated mainly through the TLR4/NF-κB signaling pathway.     

Magnolol Inhibits Tumor Necrosis Factor-α-Induced ICAM-1 Expression via Suppressing NF-κB And MAPK Signaling Pathways in Human Lung Epithelial Cells

Magnolol is a traditional Chinese medicine from the root and bark of Magnolia officinalis. It has long been used to treat anxiety, cough, headache and allergies, as well as a variety of inflammations. Lung inflammation is a key event in the pathogenesis of asthma and chronic obstructive pulmonary disease. The present study sought to examine the effects of magnolol on tumor necrosis factor (TNF)-α-induced upregulation of intercellular adhesion molecule-1 (ICAM-1), activation of the nuclear factor (NF)-κB and mitogen-activated protein kinase (MAPK) signaling pathway in cultured human pulmonary epithelial cells, and adhesion of human macrophage-like U937 cells to A549 cells. A549 cells were incubated with magnolol at 25 and 50 μmol/l. Then, 20 ng/ml TNF-α was used to activate the cells. Magnolol inhibited the growth of human pulmonary epithelial A549 cells in a dose- and time-dependent manner. Magnolol suppressed the adhesion of U937 cells to TNF-α-induced A549 cells. In cultured human pulmonary epithelial A549 cells, magnolol decreased TNF-α-induced upregulation of ICAM-1. Magnolol repressed TNF-α-induced activation of NF-κB and mitogen-activated protein kinase (MAPK) signaling pathways in A549 cells by inhibiting phosphorylation of NF-κB, p38, extracellular signal-regulated kinase (ERK) 1/2, and stress-activated protein kinase (SAPK)/c-Jun N-terminal kinase (JNK). These findings support the hypothesis that magnolol inhibits the inflammatory process in lung epithelial A549 cells by suppressing the ICAM-1 and NF-κB and MAPK signaling pathways. Taken together, these results indicate that magnolol offers significant potential as a therapeutic treatment for inflammatory diseases of the lungs including asthma, sepsis, and chronic obstructive pulmonary disease.     

Defective NF-κB Signaling in Dedifferentiated Hepatoma Cells

Dedifferentiated rat hepatoma cells contain defects that result in the loss of hepatic gene expression, including the liver-enriched HNF4/HNF1 pathway. We examined induction of NF-B, a key mediator of the inflammatory response, in hepatoma and dedifferentiated hepatoma cells. We show that exposure of dedifferentiated hepatoma cells, but not rat and human hepatoma cell lines, to proinflammatory cytokines or lipopolysaccharide resulted in rapid and sustained NF-B induction. IB- levels, but not NF-B subunit p65 or IB- levels, were elevated compared with those for parental hepatoma cells. Interestingly, LPS-mediated activation of NF-B was found to be independent of degradation of IB- or IB-. Thus, these results suggest that loci responsible for maintaining hepatic gene expression also influence cellular responses to inflammatory agents.     

TLR4-IN-C34 Inhibits Lipopolysaccharide-Stimulated Inflammatory Responses via Downregulating TLR4/MyD88/NF-κB/NLRP3 Signaling Pathway and Reducing ROS Generation in BV2 Cells

Inflammation - TLR4 signal activated by lipopolysaccharide (LPS) is involved in the pathological process of the central nervous system (CNS) diseases and the suppression of TLR4 signal may become...     

Curcumin as a therapeutic agent for blocking NF-κB activation in ulcerative colitis

Abstract

Ulcerative colitis (UC) is a chronic, relapsing, remitting, and inflammatory disorder that afflicts millions of people around the world. It carries a substantial economic burden, reducing the quality of life, ability to work, and increasing disability. Conventional medical treatment of UC includes the use of aminosalicylates, corticosteroids, and immunosuppressive drugs. However, these medicines are not always effective due to some serious side effects. Nuclear factor-kappa B (NF-κB) is a key factor in the inflammatory setting and strongly affects the course of mucosal inflammation in UC. This review aims to describe the complex role of NF-κB in UC and discuss existing pharmacological attempts by curcumin for blocking NF-κB activation to develop new therapeutic strategies in UC. Several studies have shown intriguing pharmacologic effects associated with curcumin, which inhibits NF-κB expression by regulating NF-κB/IkB pathway and down-regulation expression of pro-inflammatory cytokines, such as Interleukin (IL)-1, IL-6, IL-8, and tumor necrosis factor (TNF)-α. The efficacy of curcumin has been confirmed in several experimental models of UC. Furthermore, curcumin significantly induced clinical remission in active mild-to-moderate UC patients and reduced clinical relapse in quiescent UC patients. The inhibitory effects of curcumin on NF-κB and its unrivaled safety profile indicate that it remains effective for the treatment of UC. In addition, curcumin is a nontoxic, inexpensive, and easily available natural polyphenol. In conclusion, curcumin can be used as a potential and safe drug in the management of patients with remission and mild-to-moderate UC.     

Sargahydroquinoic Acid,a Cyclooxygenase-2 Inhibitor,Attenuates Inflammatory Responses by Regulating NF-κB Inactivation and Nrf2 Activation in Lipopolysaccharide-Stimulated Cells

Inflammation - Sargahydroquinoic acid (SHQA) is a major plastoquinone in Sargassum macrocarpum and has shown the capacity to prevent inflammation and oxidative stress. However, the protective...     

Dichloromethane Fraction of Laminaria japonica Ethanolic Extract Inhibits Lipopolysaccharide-Induced Nitric Oxide Synthase and Cyclooxygenase-2 Expression in RAW 264.7 Cells via NF-κB Pathway

Strong anti-inflammatory activity has been found in Laminaria japonica dichloromethane fraction (LDF); however, the molecular mechanisms underlying its anti-inflammatory activity are not reported. Our results indicated that LDF inhibited LPS-induced nitric oxide and prostaglandin E(2) production in a dose-dependent manner and suppressed the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) in RAW 264.7 cells. Also, levels of pro-inflammatory cytokines such as tumor necrosis factor-α, interleukin (IL)-1β and IL-6 were remarkably reduced by LDF in LPS-treated RAW 264.7 cells. LDF greatly inhibited promoter activity of nuclear factor-κB (NF-κB) and translocation of NF-κB subunits by prevention of the degradation of inhibitor κB-α in LPS-treated RAW 264.7 cells (p?相似文献   

Tumor necrosis factor receptor family costimulation increases regulatory T-cell activation and function via NF-κB

Several drugs targeting members of the TNF superfamily or TNF receptor superfamily (TNFRSF) are widely used in medicine or are currently being tested in therapeutic trials. However, their mechanism of action remains poorly understood. Here, we explored the effects of TNFRSF co-stimulation on murine Foxp3⁺ regulatory T cell (Treg) biology, as they are pivotal modulators of immune responses. We show that engagement of TNFR2, 4-1BB, GITR, and DR3, but not OX40, increases Treg proliferation and survival. Triggering these TNFRSF in Tregs induces similar changes in gene expression patterns, suggesting that they engage common signal transduction pathways. Among them, we identified a major role of canonical NF-κB. Importantly, TNFRSF co-stimulation improves the ability of Tregs to suppress colitis. Our data demonstrate that stimulation of discrete TNFRSF members enhances Treg activation and function through a shared mechanism. Consequently, therapeutic effects of drugs targeting TNFRSF or their ligands may be mediated by their effect on Tregs.     

IRF9 as a negative regulator involved in TRIF-mediated NF-κB pathway in a teleost fish,Miichthys miiuy

Proinflammatory cytokines and type I IFNs were produced by TLR signaling and these responses are crucial for host defensive responses against pathogens. In order to avoid harmful and inappropriate inflammatory responses, there are multiple mechanisms to negatively regulate TLR signaling. In this paper, we have firstly studied IRF9 functions as a negative regulator involved in TRIF-mediated NF-κB pathway. Moreover, we found inhibitory effect of IRF9 primary depends on DBD domain. Interestingly, we also demonstrated that else mutants of IRF9, except for IRF9-ΔDBD, have different inhibitory effects upon TRIF-mediated NF-κB pathway. This study provides a novel evidence about the negatively regulation of innate immune signaling pathway in teleost fish. In addition, this finding provides new insights into the regulatory mechanism in mammals.     

Short-term roxithromycin treatment attenuates airway inflammation via MAPK/NF-κB activation in a mouse model of allergic asthma

Objective

We investigated whether roxithromycin reduces ovalbumin-specific allergic asthma symptoms in mice, and we further investigated the inhibitory mechanism of roxithromycin in ovalbumin-specific allergic asthma.

Methods

Mice were divided into five groups (n?=?10 for each): control group, roxithromycin-treated groups (5, 20 and 40?mg/kg) and ovalbumin-challenged group. We measured the recruitment of inflammatory cells into the bronchoalveolar lavage fluid (BALF) or the lung tissues by Kwik-Diff and hematoxylin and eosin (H&;E) staining, goblet cell hyperplasia by alcian blue–periodic acid–Schiff (AB-PAS) staining, airway hyperresponsiveness (AHR) by whole-body plethysmograph chamber, cytokine and immunoglobulin E (IgE) levels by ELISA, and the activation of mitogen-activated protein (MAP) kinases and nuclear factor-kappa B (NF-κB) in the lung tissues by Western blotting.

Results

Treatment with roxithromycin resulted in fewer inflammatory cells in the BALF and peribronchial areas, and decreased AHR, goblet cell hyperplasia, IgE levels and inflammatory cytokines, as well as MAP kinases and NF-κB activation, which are increased in lung tissues of mice with ovalbumin-induced allergic asthma.

Conclusions

Our data suggest that oral administration of roxithromycin suppresses ovalbumin-induced airway inflammation and AHR by regulating the inflammatory cytokines via MAP kinases/NF-κB pathway in inflammatory cells. Based on these results, we suggest that roxithromycin may be used as a therapeutic agent for allergy-induced asthma.     

Aberrant Low Expression of A20 in Tumor Necrosis Factor-α-stimulated SLE Monocytes Mediates Sustained NF-κB Inflammatory Response

The aberrantly activated monocytes and nuclear factor-kappaB (NF-κB) pathway contribute to the pathogenesis of systemic lupus erythematosus (SLE), and the aberrantly activated NF-κB is associated with defects in the anti-inflammatory A20 in SLE. However, whether SLE monocytes express A20 and whether the A20 expression under sustained proinflammatory stimulation is altered to contribute to the uncontrolled NF-κB inflammatory response are unclear. In this study, we found that the freshly isolated monocytes from SLE patients and healthy controls did not differ in expression levels of IL-1β, IκBα and A20. After TNF-α stimulation for 48?h, the monocytes from both groups expressed higher levels of IL-1β and IκBα than the monocytes without TNF-α treatment. Although the increased levels of NF-κB were observed in the nucleus of both the SLE and control monocytes after 24?h of TNF-α stimulation, the enhancement in SLE monocytes was significantly more robust than in the control monocytes. In addition, while the p-IκBα level in healthy monocytes was increased, the p-IκBα level in SLE monocytes was slightly decreased after TNF-α stimulation. Interestingly, after TNF-α treatment, the A20 expression in SLE monocytes was not markedly altered compared with the untreated SLE monocytes; moreover, the SLE monocytes expressed significantly lower A20 than healthy monocytes with TNF-α treatment at each time point. Results in this study demonstrate that TNF-α activates a significant NF-κB inflammatory response in SLE monocytes, which is at least partially mediated by the aberrantly low expression of A20 upon TNF-α stimulation, contributing to the prolonged inflammatory response in SLE.     

Thymol Inhibits LPS-Stimulated Inflammatory Response via Down-Regulation of NF-κB and MAPK Signaling Pathways in Mouse Mammary Epithelial Cells

Thymol is a natural monoterpene phenol primarily found in thyme, oregano, and tangerine peel. It has been shown to possess anti-inflammatory property both in vivo and in vitro. In the present paper, we studied the anti-inflammatory effect of thymol in lipopolysaccharide (LPS)-stimulated mouse mammary epithelial cells (mMECs). The mMECs were stimulated with LPS in the presence or absence of thymol (10, 20, 40 μg/mL). The concentrations of tumor necrosis factor α (TNF-α), interleukin (IL)-6, and IL-1β in the supernatants of culture were determined using enzyme-linked immunosorbent assay. Cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), extracellular signal-regulated protein kinase (ERK), c-Jun N-terminal kinase (JNK), nuclear factor-κB (NF-κB), and inhibitor protein of NF-κB (IκBα) were measured using western blot. The results showed that thymol markedly inhibited the production of TNF-α and IL-6 in LPS-stimulated mMECs. The expression of iNOS and COX-2 was also suppressed by thymol in a dose-dependent manner. Furthermore, thymol blocked the phosphorylation of IκBα, NF-κB p65, ERK, JNK, and p38 mitogen-activated protein kinases (MAPKs) in LPS-stimulated mMECs. These results indicate that thymol exerted anti-inflammatory property in LPS-stimulated mMECs by interfering the activation of NF-κB and MAPK signaling pathways. Thereby, thymol may be a potential therapeutic agent against mastitis.     

Disturbed Cyclical Stretch of Endothelial Cells Promotes Nuclear Expression of the Pro-Atherogenic Transcription Factor NF-κB

Exposure of endothelial cells to low and multidirectional blood flow is known to promote a pro-atherogenic phenotype. The mechanics of the vessel wall is another important mechano-stimulus within the endothelial cell environment, but no study has examined whether changes in the magnitude and direction of cell stretch can be pro-atherogenic. Herein, we developed a custom cell stretching device to replicate the in vivo stretch environment of the endothelial cell and examined whether low and multidirectional stretch promote nuclear translocation of NF-κB. A fluid–structure interaction model of the device demonstrated a nearly uniform strain within the region of cell attachment and a negligible magnitude of shear stress due to cyclical stretching of the cells in media. Compared to normal cyclical stretch, a low magnitude of cyclical stretch or no stretch caused increased expression of nuclear NF-κB (p = 0.09 and p < 0.001, respectively). Multidirectional stretch also promoted significant nuclear NF-κB expression, comparable to the no stretch condition, which was statistically higher than the low (p < 0.001) and normal (p < 0.001) stretch conditions. This is the first study to show that stretch conditions analogous to atherogenic blood flow profiles can similarly promote a pro-atherogenic endothelial cell phenotype, which supports a role for disturbed vessel wall mechanics as a pathological cell stimulus in the development of advanced atherosclerotic plaques.     

The Anti-Death Machinery in IKK/NF-κB Signaling

The most extensively studied function of NF-κB is its ability to promote cell survival through induction of target genes, whose products inhibit various aspects of the apoptotic machinery in both normal and malignant cells. Recent studies, however, indicate that NF-κB activation can also suppress programmed necrosis through induction of genes encoding anti-oxidant proteins. Since tumor cells often use NF-κB pathway as a shield to escape the killing of conventional anti-cancer therapies, intervention of IKK/NF-κB signaling would be a promising option to improve the efficacy of cancer treatment.     

Effects of Ergosterol on COPD in Mice via JAK3/STAT3/NF-κB Pathway

The present study was to evaluate the effect of ergosterol (ER) on CS (cigarette smoke)-induced chronic obstructive pulmonary disease (COPD) in mice. Fifty male ICR mice were randomly assigned to five groups: control group, CS group, CS + dexamethasone (Dex, 2 mg/kg) group, CS + ER (ER, 25 mg/kg) group, CS + ER (ER, 50 mg/kg). H&E staining demonstrated that ER inhibited CS-induced pathological injury in lung tissue. Besides, ER could restore the activities of superoxide dismutase (SOD) in serum and in the lung, catalase (CAT) in serum and reduce the content of malondialdehyde (MDA) in serum and in the lung. ER also inhibited pro-inflammatory cytokines including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) in serum and the lung. Furthermore, ER significantly inhibited the protein expression of JAK3/STAT3/NF-κB pathway in CS-induced mice. Our findings suggested that ER might effectively ameliorate the progression of COPD via JAK3/STAT3/NF-κB pathway in mice.     

AGEs/RAGE complex upregulates BACE1 via NF-κB pathway activation

Although the pathogenesis of sporadic Alzheimer disease (AD) is not clearly understood, it is likely dependent on several age-related factors. Diabetes is a risk factor for AD, and multiple mechanisms connecting the 2 diseases have been proposed. Hyperglycemia enhances the formation of advanced glycation end products (AGEs) that result from the auto-oxidation of glucose and fructose. The interaction of AGEs with their receptor, named RAGE, elicits the formation of reactive oxygen species that are also believed to be an early event in AD pathology. To investigate a functional link between the disorders diabetes and AD, the effect of 2 AGEs, pentosidine and glyceraldehydes-derived pyridinium (GLAP), was studied on BACE1 expression both in vivo, in streptozotocin treated rats, and in vitro in differentiated neuroblastoma cells. We showed that pentosidine and GLAP were able to upregulate BACE1 expression through their binding with RAGE and the consequent activation of NF-κB. In addition, both pentosidine and GLAP were found to be increased in the brain in sporadic AD patients. Our findings demonstrate that activation of the AGEs/RAGE axis, by upregulating the key enzyme for amyloid-β production, provides a pathologic link between diabetes mellitus and AD.