The AMP-activated protein kinase (AMPK) is a pivotal serine/threonine kinase participating in the regulation of glucose, lipid as well as protein metabolism and maintenance of energy homeostasis. Recent studies demonstrated that AMPK can also inhibit nuclear factor-κB, suppress the expression of inflammatory genes and attenuate inflammatory injury through phosphorylating its downstream targets including SIRT1, PGC-lα, p53 and FoxO3a. In addition, the widely used antidiabetic metformin also exerts its anti-inflammatory effects through activating AMPK. Therefore, AMPK is emerging as a promising novel target for the development of anti-inflammatory drugs. This review summarized the anti-inflammatory effects of AMPK and the underling molecular mechanisms.
AMP-Activated Protein Kinases ; metabolism ; Homeostasis ; Inflammation ; enzymology ; Metformin ; pharmacology ; NF-kappa B ; antagonists & inhibitors ; Phosphorylation

<b>OBJECTIVEb>Observing the time course and establishing the model of kappaB-decoy oligodeoxynucleotides (rcB-decoy) inhibiting the activity of NF-kappaB in the PC12 cells.

<b>METHODSb>PC12 cells cultivating in the 6 wells plate were divided into 3 groups, experimental group: adding kappaB-decoy complex (6 microg DNA/well), the control group: adding scrambled-decoy complex, the normal group: adding lipid-Lipofectamine 2000, transfer and cultivate 48 h, then lipopolysaccharide (LPS, 200 ng/ml) was added in the cells for 0.5-4 h. The immunocytochemistry and Western blot were used to measure the expression or the activity of NF-kappaB in PC12 cells.

<b>RESULTSb>In PC12 cells, compared with normal group, the expression of NF-kappaB enhanced obviously with the time of the stimulation of LPS in scrambled-decoy treated control group (P < 0.01), in 2-4 h the level reached the peak; the expression of NF-kappaB showed the stable level with the time of the stimulation of LPS in kappaB-decoy treated experimental group, compared with the control group, the expression levels were obviously lower than the respective time point of control groups (P < 0.01).

<b>CONCLUSIONb>kappaB-decoy could reduce the expression of NF-kappaB in the normal PC12 cells and inhibit the activity of NF-cB in the pathologic PC12 cells.

Animals ; Cells, Cultured ; Lipopolysaccharides ; pharmacology ; NF-kappa B ; antagonists & inhibitors ; metabolism ; Oligodeoxyribonucleotides ; pharmacology ; PC12 Cells ; Rats

<b>BACKGROUNDb>Nuclear factor kappaB (NF-kappaB) overactivation, requiring phosphorylation and degradation of its inhibitor IkappaBalpha, is the basis for chronicity of airway inflammation in asthma. Based on our previous plasmid pShuttle-IkappaBalpha, carrying an IkappaBalpha gene from human placenta, we optimized a novel IkappaBalpha mutant (IkappaBalphaM) gene, constructed and characterized its replication-deficient recombinant adenovirus (AdIkappaBalphaM), and tested whether AdIkappaBalphaM-mediated overexpression of IkappaBalphaM could inhibit the NF-kappaB activation in endothelial cells.

<b>METHODSb>IkappaBalphaM gene (203 - 1003 bp) encoding 267 amino acids, acquired by site-directed deleting N-terminal phosphorylation sites of serine 32/36, was subcloned into the pShuttle and pGEM-T vectors for further polymerase chain reaction (PCR), restriction digestion, deoxyribonucleic acid (DNA) sequencing and homology analyses. Subsequent to inserting the expression unit of pShuttle-IkappaBalphaM, containing cytomegalovirus (CMV) promoter, IkappaBalphaM complementary DNA (cDNA) and polyadenylic acid (PolyA) signals, into the type 5 adenovirus (Ad5) vector, the resultant AdIkappaBalphaM was packaged in human embryonic kidney (HEK) 293 cells by cotransfection with lipofectamine. Western blot analysis and electrophoretic mobility shift assay were utilized to detect the AdIkappaBalphaM-mediated overexpression of IkappaBalphaM in HEK293 cells and its suppressive effect on phorbol 12-myristate 13-acetate (PMA)-induced NF-kappaB activation in human umbilical vein endothelial (ECV304) cells, respectively.

<b>RESULTSb>The relevant nucleotides and deduced amino acids of 801 bp IkappaBalphaM gene were consistent with those of IkappaBalpha gene (GenBank accession number: M69043). The titer of the prepared AdIkappaBalphaM was 4.0 x 10 (12) plaque-forming units (pfu)/L. Moreover, the IkappaBalphaM gene was overexpressed in HEK293 cells, and potently inhibited the PMA-induced NF-kappaB activation in ECV304 cells dose-dependently.

<b>CONCLUSIONSb>AdIkappaBalphaM is a novel vector for both efficient transfer and specific overexpression of IkappaBalphaM gene, as well as potent inhibition of NF-kappaB activity, providing a promising strategy for gene therapy of asthma.

Adenoviridae ; genetics ; Cell Line ; Endothelial Cells ; metabolism ; Genetic Therapy ; Humans ; I-kappa B Proteins ; genetics ; Mutation ; NF-KappaB Inhibitor alpha ; NF-kappa B ; antagonists & inhibitors ; Tetradecanoylphorbol Acetate ; pharmacology

NF-kappaB, a collective name of dimeric transcription factors, is composed of members of the Rel family proteins that recognize and bind a specific DNA sequence. It is normally sequestered in the cytoplasm of non-stimulated cells by associating with a family of inhibitor proteins called IkappaBs. Exposure of cells to a variety of extra-and intra-cellular stimuli leads to the rapid proteolytic degradation of IkappaBs, which frees NF-kappaBs allowing them to translocate to the nucleus where it regulates gene transcription. NF-kappaB is involved in a lot of physiological processes such as immunity, inflammation, cell proliferation, apoptosis and even tumorigenesis by regulating the transcription of a larger number of genes. This review introduces the various mechanisms of NF-kappaB activation including a recently reported alternative activation pathway mediated by lymphotoxin alpha/beta, B cell activating factor and CD40 ligand. The signal transduction pathway leading to NF-kappaB activation via IKK in response to proinflammatory factors like TNF-alpha and IL-1 is addressed in more detail concerning the regulation of IKK activity, mechanism of IkappaB degradation and regulation of transactivation activity of NF-kappaB on different levels. Considering the important role of NF-kappaB in cell proliferation and regulation of various genes participating in apoptosis, the involvement of NF-kappaB in tumorigenesis and drug screening is also discussed.
Animals ; Drug Evaluation, Preclinical ; Humans ; I-kappa B Proteins ; metabolism ; NF-kappa B ; antagonists & inhibitors ; metabolism ; physiology ; Neoplasms ; etiology ; Signal Transduction ; Transcription, Genetic ; physiology

<b>OBJECTIVEb>Celastrol has been established as a nuclear factor-&kappa;B (NF-&kappa;B) activation inhibitor; however, the exact mechanism behind this action is still unknown. Using text-mining technology, the authors predicted that interleukin-1 receptor-associated kinases (IRAKs) are potential celastrol targets, and hypothesized that targeting IRAKs might be one way that celastrol inhibits NF-&kappa;B. This is because IRAKs are key molecules for some crucial pathways to activate NF-&kappa;B (e.g., the interleukin-1 receptor (IL-1R)/Toll-like receptor (TLR) superfamily).

<b>METHODSb>The human hepatocellular cell line (HepG2) treated with palmitic acid (PA) was used as a model for stimulating TLR4/NF-&kappa;B activation, in order to observe the potential effects of celastrol in IRAK regulation and NF-&kappa;B inhibition. The transfection of small interfering RNA was used for down-regulating TLR4, IRAK1 and IRAK4, and the Western blot method was used to detect changes in the protein expressions.

<b>RESULTSb>The results showed that celastrol could effectively inhibit PA-caused TLR4-dependent NF-&kappa;B activation in the HepG2 cells; PA also activated IRAKs, which were inhibited by celastrol. Knocking down IRAKs abolished PA-caused NF-&kappa;B activation.

<b>CONCLUSIONb>The results for the first time show that targeting IRAKs is one way in which celastrol inhibits NF-&kappa;B activation.

Hep G2 Cells ; Humans ; Interleukin-1 Receptor-Associated Kinases ; antagonists & inhibitors ; NF-kappa B ; antagonists & inhibitors ; metabolism ; Phosphorylation ; Toll-Like Receptor 4 ; antagonists & inhibitors ; physiology ; Triterpenes ; pharmacology

Lycii Cortex, a popular herb medicine in traditional Chinese medicine, is used to treat different inflammation-related diseases. The aim of our work is to find the key constituents inhibiting NF-kappaB, a key regulator of inflammation. In the investigations of cell-based in vitro assays of extracts, we found that both ethyl acetate extract and methanol extract of Lycii Cortex inhibited the TNF-alpha-induced activation of NF-kappaB. Through bioassay-guided fractionation, we identified 4 phenolic amides including trans-N-(p-coumaroyl) tyramine (1), trans-N-feruloyltyramine (2), trans-N-caffeoyltyramine (3), and dihydro-N-caffeoyltyramine (4). Four phenolic amides showed differently inhibitory activities on TNF-alpha-induced NF-kappaB activation. Trans-N-caffeoyltyramine (3) was identified as the key component with an IC50 of 18.41 micromol x L(-1). It was suggested that the hydroxyl group at C-3 in trans-N-caffeoyltyramine might be a key binding site and its C-7,8-double bond might play an important role on NF-kappaB inhibitory activities as the link of the conjugation of pi electrons leading to a partial planar conformation. It might be inferred that the biological activity of compound 3 is attributed to the structure of Michael reaction acceptor containing alpha, beta-unsaturated ketones and benzene along with hydroxyl group in o-diphenol.
Biological Assay ; Cell Line ; Drugs, Chinese Herbal ; chemistry ; isolation & purification ; pharmacology ; Humans ; Inflammation Mediators ; antagonists & inhibitors ; immunology ; Lycium ; chemistry ; Molecular Structure ; NF-kappa B ; antagonists & inhibitors ; immunology

<b>OBJECTIVEb>To investigate the inhibition consequence of NF-kappaB activity and cell viability by transfecting mutated inhibitor kappa B alpha (mI(kappa)B(alpha)) into liver cancer cell line of SMMC-7721 cells.

<b>METHODSb>The nucleic proteins of SMMC-7721 cells transfected with mI(kappa)B(alpha) plasmid and cells with empty pcDNA3 vector were used to determine not only the binding of the 32P-labelled kappaB probes by EMSA, but also the expression of NF-kappaB by western blot. Cell viability was also analyzed.

<b>RESULTSb>NF-kappaB nuclear translocation was inhibited remarkably in SMMC-7721 cells transfected with mI(kappa)B(alpha) at 0, 24, 48 and 96 hours. Furthermore, NF-kappaB was not detected in the nucleic protein of mI(kappa)B(alpha) -transfected cells at the same intended time by western blot. Compared with that of control cells, the growth of SMMC-7721 cells transfected with mI(kappa)B(alpha) was suppressed evidently, especially on the second day, the cpm values of mI(kappa)B(alpha) -transfected cells, pcDNA3-transfected cells, and control cells were 5,092.63+/-541.41, 7,851.87+/-72.76, and 8,240.8+/-603.26 respectively (t = 14.29, P<0.01; t = 10.99, P<0.01).

<b>CONCLUSIONb>Stable expression of mI(kappa)B(alpha) in SMMC-7721 cells transfected with mI(kappa)B(alpha) plasmid inhibits NF-kappaB nuclear translocation, then suppresses the cell growth.

Carcinoma, Hepatocellular ; metabolism ; pathology ; Cell Division ; Cell Line, Tumor ; Humans ; I-kappa B Proteins ; biosynthesis ; genetics ; physiology ; Liver Neoplasms ; metabolism ; pathology ; Mutation ; NF-KappaB Inhibitor alpha ; NF-kappa B ; antagonists & inhibitors ; physiology ; Transfection ; Translocation, Genetic

<b>BACKGROUNDb>This study aimed at investigating the change and significance of nuclear factor-kappaB (NF-kappaB) in cardiomyopathy induced by adriamycin (ADR) in rats.

<b>METHODSb>Sixty male Wistar rats were randomly divided into three groups: control, ADR and ADR + pyrrolidine dithiocarbamate (PDTC) groups. After 30-day experiment, myocardial histopathological observation was performed. Location and distribution of NF-kappaB p50 was examined by immunohistochemical assay. Expression of NF-kappaB p50 protein was examined by immunobolt assay. Electrophoretic Mobility Shift Assay examined activity of NF-kappaB; Myocardium p53 gene expression was examined by RT-PCR analysis.

<b>RESULTSb>The myocardial lesions of rats were less pronounced in ADR + PDTC group than in ADR group. Compared with control group, there were many myocardium nucleuses, which expressed NF-kappaB p50 and distribute under epicardium. Expression of NF-kappaB p50 protein in nucleus increased significantly in ADR group. The NF-kappaB binding activity increased significantly in ADR group. Myocardium expressions of p53 mRNA increased in ADR group.

<b>CONCLUSIONSb>The NF-kappaB binding activity increased significantly in cardiomyopathy induced by ADR in rats. Moreover, NF-kappaB plays an important role in causing degeneration of myocardial tissue and regulating expression of related-apoptosis genes.

Animals ; Cardiomyopathies ; chemically induced ; metabolism ; pathology ; Doxorubicin ; toxicity ; Electrophoretic Mobility Shift Assay ; Genes, p53 ; Male ; NF-kappa B ; antagonists & inhibitors ; metabolism ; NF-kappa B p50 Subunit ; Protein Precursors ; Rats ; Rats, Wistar

<b>BACKGROUNDb>The aim of this study was to explore whether the inhibition of nuclear factor-kappaB (NF-kappaB) activation by mutant IkappaBalpha (S32, 36-->A) can enhance TNF-alpha-induced apoptosis of leukemia cells and to investigate the possible mechanism.

<b>METHODSb>The mutant IkappaBalpha gene was transfected into HL-60 cells by liposome-mediated techniques. G418 resistant clones stably expressing mutant IkappaBalpha were obtained by the limiting dilution method. TNF-alpha-induced NF-kappaB activation was measured by electrophoretic mobility shift assay (EMSA). The expression of bcl-xL was detected by RT-PCR and Western blot after 4 hours exposure of parental HL-60 and transfected HL-60 cells to a variety of concentrations of TNF-alpha. The percentage of apoptotic leukemia cells was evaluated by flow cytometry (FCM).

<b>RESULTSb>Mutant IkappaBalpha protein was confirmed to exist by Western blot. The results of EMSA showed that NF-kappaB activation by TNF-alpha in HL-60 cells was induced in a dose-dependent manner, but was almost completely inhibited by mutant IkappaBalpha repressor in transfected cells. The levels of bcl-xL mRNA and protein in HL-60 cells increased after exposure to TNF-alpha, but changed very little in transfected HL-60 cells. The inhibition of NF-kappaB activation by mutant IkappaBalpha enhanced TNF-alpha-induced apoptosis. The cytotoxic effects of TNF-alpha were amplified in a time- and dose-dependent manner.

<b>CONCLUSIONSb>NF-kappaB activation plays an important role in the resistance to TNF-alpha-induced apoptosis. The inhibition of NF-kappaB by mutant IkappaBalpha could provide a new approach that may enhance the anti-leukemia effects of TNF-alpha or even of other cytotoxic agents.

Apoptosis ; drug effects ; Gene Expression Regulation, Leukemic ; HL-60 Cells ; Humans ; I-kappa B Proteins ; physiology ; NF-KappaB Inhibitor alpha ; NF-kappa B ; antagonists & inhibitors ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; Tumor Necrosis Factor-alpha ; pharmacology ; bcl-X Protein

PURPOSE: Based on the close relationship between histamine and interleukin 6 (IL-6), we hypothesized that histamine may regulate the production of cytokines, such as IL-6, during allergic inflammation. Here, we examined the role of histamine in IL-6 production and histamine receptor activity in nasal fibroblasts, along with the mechanisms underlying these effects. METHODS: Experiments were performed using nasal fibroblasts from 8 normal patients. RT-PCR was used to identify the major histamine receptors expressed in nasal fibroblasts. Fibroblasts were then treated with histamine with or without histamine-receptor antagonists, and monitored for IL-6 production using an ELISA. Four potential downstream signaling molecules, p38, extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and NF-kappaB, were evaluated by Western blot, and a luciferase reporter assay. RESULTS: Elevated expression was seen for all histamine receptors, with IL-6 protein levels increasing significantly following histamine stimulation. Among the histamine-receptor specific antagonists, only the H1R antagonist significantly decreased IL-6 production in histamine-stimulated nasal fibroblasts. Histamine increased the expression level of phosphorylated p38 (pp38), pERK, and pJNK, as well as NF-kappaB induction. The H1R antagonist actively suppressed pp38 and NF-kappaB expression in histamine-induced nasal fibroblasts, but not pERK and pJNK. The p38 inhibitor strongly attenuated IL-6 production in histamine-stimulated nasal fibroblasts. CONCLUSIONS: The data presented here suggest that antihistamines may be involved in the regulation of cytokines, such as IL-6, due to the role of histamine as an inflammatory mediator in nasal fibroblasts.
Blotting, Western ; Cytokines ; Enzyme-Linked Immunosorbent Assay ; Fibroblasts* ; Histamine Antagonists ; Histamine* ; Humans ; Inflammation ; Interleukin-6* ; JNK Mitogen-Activated Protein Kinases ; Luciferases ; NF-kappa B* ; Nose ; Phosphotransferases ; Receptors, Histamine