NF-kappaB as a therapeutic target in chronic inflammation: recent advances

Modified yukmijihwangtang suppresses the production of proinflammatory cytokines in the intravesical hydrochloric acid-induced cystitis rat model via the NF-κB pathway

Yukmijihwangtang (YM), a boiled extract of medicinal plants, has been prescribed for patients with kidney dysfunction in Korea; however, the mechanism underlying its therapeutic effects has not been fully elucidated. This study was conducted to evaluate the beneficial effects on bladder function by using modified YM (M-YM), which included Ulmi radicis cortex in addition to the six traditional medicinal plants in YM. Bladder irritation of the rats was caused by intravesical instillation of HCl. The animals were divided into six groups: sham group, cystitis-injury group with no treatment, cystitis-injury group with prednisolone treatment (5 mg/kg), and cystitis-injury with M-YM treatment (100, 200 or 500 mg/kg groups). Whole bladders were collected at day eight after injury. Samples were analyzed by histological and immunological examinations. An in vitro study was performed to determine whether M-YM extracts inhibit lipopolysaccharide (LPS)-induced nitric oxide (NO) production and IκB phosphorylation in a human uroepithelial cell line of T24 cells. Administration of M-YM notably improved bladder histological changes, and suppressed IL-6/TNF α production and IκB phosphorylation in a rat model of chronic cystitis. M-YM also inhibited LPS-induced NO production and IκB phosphorylation in T24 cells. This study suggests that administration of M-YM might be an applicable therapeutic traditional medicine for the treatment of interstitial cystitis.

Anti-inflammatory effect of Lycium Fruit water extract in lipopolysaccharide-stimulated RAW 264.7 macrophage cells

Lycium Fruit has been used as a traditional drug for low back pain and chronic cough in east-Asian countries. However, inhibitory effects of Lycium Fruit water extract (LFWE) on inflammation remain unknown. In this study, we investigated the inhibitory effects of LFWE on pro-inflammatory mediator production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. LFWE inhibited LPS-induced nitric oxide (NO), prostaglandin (PG) E₂, tumor necrosis factor (TNF)-α and interleukin (IL)-6 production as well as their synthesizing enzyme inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 gene expression. Furthermore, LFWE inhibited phosphorylations of extracellular signal-regulated kinase (ERK), p38 and c-Jun NH₂-terminal kinase (JNK) mitogen-activated protein kinases (MAPKs) as well as suppression of IκBα degradation and nuclear translocation of nuclear factor (NF)-κB upon LPS stimulation. In addition, LFWE suppressed NO, PGE₂, TNF-α and IL-6 production in LPS-stimulated peritoneal macrophage cells. Taken together, our results suggest that LFWE inhibits the production of various inflammatory mediators via blockade on the MAPKs and NF-κB pathways. This finding first explains the mechanism of anti-inflammatory effect by LFWE in LPS-stimulated macrophage cells.

Dietary blue pigments derived from genipin, attenuate inflammation by inhibiting LPS-induced iNOS and COX-2 expression via the NF-κB inactivation

BACKGROUND AND PURPOSE

The edible blue pigments produced by gardenia fruits have been used as value-added colorants for foods in East Asia for 20 years. However, the biological activity of the blue pigments derived from genipin has not been reported.

METHODOLOGY/PRINCIPAL FINDINGS

The anti-inflammatory effect of blue pigments was studied in lipopolysaccharide (LPS) stimulated RAW 264.7 macrophage in vitro. The secretions of nitric oxide (NO) and prostaglandin E(2) (PGE(2)) were inhibited in concentration-dependent manner by blue pigments. Real-time reverse-transcription polymerase chain reaction (Real-time RT-PCR) analyses demonstrated that the mRNA expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin (IL)-6, and tumor necrosis factor alpha (TNF-α) was inhibited, moreover, ELISA results showed that the productions of IL-6 and TNF-α were inhibited. Cell-based ELISA revealed the COX-2 protein expression was inhibited. The proteome profiler array showed that 12 cytokines and chemokines involved in the inflammatory process were down-regulated by blue pigments. Blue pigments inhibited the nuclear transcription factor kappa-B (NF-κB) activation induced by LPS, and this was associated with decreasing the DNA-binding activity of p65 and p50. Furthermore, blue pigments suppressed the degradation of inhibitor of κB (IκB) α, Inhibitor of NF-κB Kinase (IKK) α, IKK-β, and phosphorylation of IκB-α. The anti-inflammatory effect of blue pigments in vivo was studied in carrageenan-induced paw edema and LPS-injecting ICR mice. Finally, blue pigments significantly inhibited paw swelling and reduced plasma TNF-α and IL-6 production in vivo.

CONCLUSIONS AND IMPLICATIONS

These results suggest that the anti-inflammatory properties of blue pigments might be the results from the inhibition of iNOS, COX-2, IL-6, IL-1β, and TNF-α expression through the down-regulation of NF-κB activation, which will provide strong scientific evidence for the edible blue pigments to be developed as a new health-enhancing nutritional food for the prevention and treatment of inflammatory diseases.

Effects of (±)-praeruptorin A on airway inflammation, airway hyperresponsiveness and NF-κB signaling pathway in a mouse model of allergic airway disease

The root of Peucedanum praeruptorum Dunn is a traditional Chinese medicine commonly used to treat asthma in China. (±)-praeruptorin A (PA) is the most abundant constituent of P. praeruptorum Dunn, the effects of which on asthma were investigated using a murine model of allergic airway disease. BALB/c mice were sensitized and challenged by ovalbumin to induce airway inflammation. PA was administered intragastrically before every OVA challenge. Airway responsiveness was measured by a lung function analysis system. The number of total leukocytes in bronchoalveolar lavage fluid was counted using a hemocytometer, and differential cell counts were determined using Diff-Quick-stained smears. Histopathology of lung tissue was analyzed by hematoxylin-eosin and Congo red staining. Levels of inflammatory mediators in bronchoalveolar lavage fluid and immunoglobulins in serum were measured by enzyme-linked immunosorbent assay. The expression of pulmonary eotaxin was detected by immunohistochemistry and reverse transcription polymerase chain reaction. The activation of NF-κB was evaluated by electrophoretic mobility shift assay and western blot analysis. Compared with model group, PA significantly reduced airway hyperresponsiveness and airway eosinophilic inflammation, improved pathologic lesion of the lungs, reduced levels of interleukin (IL)-4, IL-5, IL-13 and LTC₄ in bronchoalveolar lavage fluid and immunoglobulin (Ig) E in serum, and inhibited eotaxin protein and mRNA expression, IκBα degradation, NF-κB nuclear translocation, NF-κB DNA-binding activity and RelA/p65 phosphorylation in lung, which suggested that PA can significantly suppress OVA-induced airway inflammation and airway hyperresponsiveness in mice, showing great therapeutic potential for the treatment of allergic asthma.

Fermentation by Lactobacillus enhances anti-inflammatory effect of Oyaksungisan on LPS-stimulated RAW 264.7 mouse macrophage cells

BACKGROUND

Oyaksungisan (OY) has been used as a traditional drug in east-Asian countries. However, its effect on inflammation still remains unknown. In this study, to provide insight into the biological effects of OY and OY fermented by Lactobacillus, we investigated their effects on lipopolysaccharide (LPS)-mediated inflammation in the RAW 264.7 murine macrophage cells.

METHODS

The investigation was focused on whether OY and fermented OYs could inhibit the production of pro-inflammatory mediators such as nitric oxide (NO) and prostaglandin (PG) E2 as well as the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, tumor necrosis factor (TNF)-α, interleukin (IL)-6, nuclear factor (NF)-κB and mitogen-activated protein kinases (MAPKs) in LPS-stimulated RAW 264.7 cells.

RESULTS

We found that OY inhibits a little LPS-induced NO, PGE2, TNF-α and IL-6 productions as well as the expressions of iNOS and COX-2. Interestingly, the fermentation significantly increased its inhibitory effect on the expression of all pro-inflammatory mediators. Furthermore, the fermented OYs exhibited elevated inhibition on the translocation of NF-κB p65 through reduced IκBα degradation as well as the phosphorylations of extracellular signal-regulated kinase (ERK), p38 and c-Jun NH2-terminal kinase (JNK) MAPKs than untreated control or original OY.

CONCLUSIONS

Finally, the fermentation by Lactobacillus potentiates the anti-inflammatory effect of OY by inhibiting NF-κB and MAPK activity in the macrophage cells.

BDMC33, A curcumin derivative suppresses inflammatory responses in macrophage-like cellular system: role of inhibition in NF-κB and MAPK signaling pathways

Our preliminary screening has shown that curcumin derivative BDMC33 [2,6-bis(2,5-dimethoxybenzylidene)cyclohexanone] exerted promising nitric oxide inhibitory activity in activated macrophages. However, the molecular basis and mechanism for its pharmacological action is yet to be elucidated. The aim of this study was to investigate the anti-inflammatory properties of BDMC33 and elucidate its underlying mechanism action in macrophage cells. Our current study demonstrated that BDMC33 inhibits the secretion of major pro-inflammatory mediators in stimulated macrophages, and includes NO, TNF-α and IL-1β through interference in both nuclear factor kappaB (NF-κB) and mitogen activator protein kinase (MAPK) signaling cascade in IFN-γ/LPS-stimulated macrophages. Moreover, BDMC33 also interrupted LPS signaling through inhibiting the surface expression of CD-14 accessory molecules. In addition, the inhibitory action of BDMC33 not only restricted the macrophages cell (RAW264.7), but also inhibited the secretion of NO and TNF-α in IFN-γ/LPS-challenged microglial cells (BV-2). The experimental data suggests the inflammatory action of BDMC33 on activated macrophage-like cellular systems, which could be used as a future therapeutic agent in the management of chronic inflammatory diseases.

A novel NF-κB inhibitor, dehydroxymethylepoxyquinomicin, ameliorates inflammatory colonic injury in mice

BACKGROUND

In inflammatory bowel disease (IBD), gut inflammation is associated with the activation of nuclear factor kappa B (NF-κB), a key pro-inflammatory transcription factor.

AIM

To investigate the therapeutic potential of a novel, specific NF-κB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), we examined its effect on IBD using murine experimental colitis models.

METHODS

The in vitro effect of DHMEQ was evaluated by inflammatory cytokine production and p65 immunostaining using HT-29 and RAW264.7 cells. The in vivo therapeutic effect of DHMEQ was studied in colitis induced by dextran sulphate sodium (DSS) and trinitrobenzenesulphonic acid (TNBS). In these, progression and severity of colitis was mainly assessed by the disease activity index (DAI), histopathology, cellular infiltration, and mRNA expression levels of pro-inflammatory cytokines in the colonic tissues.

RESULTS

In RAW264.7 cells, DHMEQ significantly inhibited tumour necrosis factor (TNF)-α and interleukin (IL)-6 production induced by LPS in a dose-dependent manner by blocking the nuclear translocation of NF-κB. In addition, DHMEQ inhibited IL-8 production induced by LPS in HT-29 cells. DHMEQ significantly ameliorated DSS colitis as assessed by DAI scores, colonic oedema, and histological scores. Immunohistochemistry revealed that DHMEQ inhibited colonic infiltration of nuclear p65(+) cells, CD4(+) lymphocytes, and F4/80(+) macrophages. mRNA expression levels of the pro-inflammatory cytokines, such as IL-1β, TNF-α, IL-6, IL-12p40, IL-17, and MCP-1 were also suppressed by DHMEQ administration. Furthermore, DHMEQ significantly ameliorated TNBS colitis as assessed by body-weight changes and histological scores.

CONCLUSION

DHMEQ ameliorated experimental colitis in mice. These results indicate that DHMEQ appears to be an attractive therapeutic agent for IBD.

Small interfering RNA-mediated knockdown of NF-κBp65 attenuates neuropathic pain following peripheral nerve injury in rats

Recent reports show that the nuclear factor-κB (NF-κB) can control numerous genes encoding inflammatory and nociceptive mediators and play an important role in the development of central pain sensitization. The aim of the present study is to assess the role of NF-κB signal pathway and its downstream pro-inflammatory cytokines in the modulation of neuropathic pain, by using small interfering RNAs (siRNAs) technique, which has been shown to result in potent, long-lasting post-transcriptional silencing of specific genes. We developed a highly efficient method of lentivirus-mediated delivery of short-hairpin RNA (shRNA) targeting NF-κBp65 for gene silencing. This method successfully transduced LV-shNF-κBp65 into cultured spinal cord neurons in vitro and spinal cord cells in vivo, inhibited the expression of NF-κBp65 and pro-inflammatory factors (TNF-α, IL-1β and IL-6) and alleviated mechanical allodynia and thermal hyperalgesia for more than 4weeks in chronic constriction injury (CCI) model of rats. Taken together, our results suggest that siRNA against NF-κBp65 is a potential strategy for analgesia. Furthermore, the lentiviral vector derived shRNA approach shows a great promise for the management of neuropathic pain and the study of functional NF-κBp65 gene expression.

Dysfunctional nucleus tractus solitarius: its crucial role in promoting neuropathogenetic cascade of Alzheimer's dementia--a novel hypothesis

The pathophysiological mechanism(s) underlying Alzheimer's disease (AD) still remain unclear, and no disease-modifying or prophylactic therapies are currently available. Unraveling the fundamental neuropathogenesis of AD is an important challenge. Several studies on AD have suggested lesions in a number of CNS areas including the basal forebrain, hippocampus, entorhinal cortex, amygdale/insula, and the locus coeruleus. However, plausible unifying studies on the upstream factors that involve these heterogeneous regions and herald the onset of AD pathogenesis are not available. The current article presents a novel nucleus tractus solitarius (NTS) vector hypothesis that underpins several disparate biological mechanisms and neural circuits, and identifies relevant hallmarks of major presumptive causative factor(s) linked to the NTS, in older/aging individuals. Aging, obesity, infection, sleep apnea, smoking, neuropsychological states, and hypothermia-all activate inflammatory cytokines and oxidative stress. The synergistic impact of systemic proinflammatory mediators activates microglia and promotes neuroinflammation. Acutely, the innate immune response is protective defending against pathogens/toxins; however, when chronic, it causes neuroinflammation and neuronal dysfunction, particularly in brainstem and neocortex. The NTS in the brainstem is an essential multiple signaling hub, and an extremely important central integration site of baroreceptor, chemoreceptor, and a multitude of sensory afferents from gustatory, gastrointestinal, cardiac, pulmonary, and upper airway systems. Owing to persistent neuroinflammation, the dysfunctional NTS exerts deleterious impact on nucleus ambiguus, dorsal motor nucleus of vagus, hypoglossal, parabrachial, locus coeruleus and many key nuclei in the brainstem, and the hippocampus, entorhinal cortex, prefrontal cortex, amygdala, insula, and basal forebrain in the neocortex. The neuronal and synaptic dysfunction emanating from the inflamed NTS may affect its interconnected pathways impacting almost the entire CNS--which is already primed by neuroinflammation, thus promoting cognitive and neuropsychiatric symptoms. The upstream factors discussed here may underpin the neuropathopgenesis of AD. AD pathology is multifactorial; the current perspective underscores the value of attenuating disparate upstream factors--in conjunction with anticholinesterase, anti-inflammatory, immunosuppressive, and anti-oxidant pharmacotherapy. Amelioration of the NTS pathology may be of central importance in countering the neuropathological cascade of AD. The NTS, therefore, may be a potential target of novel therapeutic strategies.

Effects of globin digest and its active ingredient Trp-Thr-Gln-Arg on galactosamine/lipopolysaccharide-induced liver injury in ICR mice

AIMS

We investigated the effects of globin digest (GD) and its active ingredient Trp-Thr-Gln-Arg (WTQR) on galactosamine/lipopolysaccharide (GalN/LPS)-induced liver injury in imprinting control region (ICR) mice.

MAIN METHODS

The effects of WTQR and GD on the liver injury were examined by measuring the survival rate, serum aminotransferase activities, hepatic components, antioxidant enzyme activities, histopathological analysis, serum levels and hepatic gene expression of tumor necrosis factor-alpha (TNF-α), macrophage inflammatory protein-2 (MIP-2), and nitric oxide (NO) or inducible nitric oxide synthase (iNOS), and nuclear factor-kappa B (NF-κB) p65 content in GalN/LPS-treated ICR mice. RAW264 mouse macrophages were used to confirm the anti-inflammatory effects of WTQR and GD on the macrophages.

KEY FINDINGS

WTQR and GD increased the survival rate, suppressed the serum aminotransferase activities, serum levels and hepatic gene expression of TNF-α, MIP-2, and NO or iNOS, and nuclear NF-κB p65 content in GalN/LPS-treated mice; decreased the oxidized glutathione content, increased the superoxide dismutase activity, and decreased the histopathological grade values of the hepatocyte necrosis and lobular inflammation in GalN/LPS-injured liver; and suppressed the release levels and gene expression of TNF-α, MIP-2, and NO or iNOS, and nuclear NF-κB p65 content in LPS-stimulated RAW264 macrophages. WTQR and GD may improve the antioxidant defense system and inflammatory status in GalN/LPS-injured liver.

SIGNIFICANCE

These findings indicate that WTQR and GD have hepatoprotective effects on GalN/LPS-induced liver injury in ICR mice.

Topical fluticasone propionate: intervention and maintenance treatment options of atopic dermatitis based on a high therapeutic index

Fluticasone propionate (FP), a medium potent glucocorticoid (class III) of carbothioate nature with a favourable benefit/risk ratio, has emerged as a standard medication for the topical treatment of inflammatory skin disorders, in particular atopic dermatitis (AD). FP is available as a 0.05% cream and a 0.005% ointment formulation. The glucocorticoid is characterized by high lipophilicity, high affinity binding to the glucocorticoid receptor and a rapid hepatic biotransformation. Though skin blanching following topical application of FP surpasses that given with glucocorticoids of medium strength, clinical trials show a low potential of FP for local and systemic adverse effects. Even in paediatric patients with AD as well as in difficult-to-treat areas like face, eyelids and intertriginous areas, FP proved to be both effective and safe. Thus, the therapeutic effects of FP clearly outweigh the unwanted effects. Correspondingly, a therapeutic index of 2.0 can be attributed to this glucocorticoid. In this respect, topical FP does not differ from other topical glucocorticoids with increased benefit-to-risk ratio, e.g. prednicarbate, methylprednisolone aceponate and mometasone furoate. However, randomized controlled trials do not only support conventional intervention but also innovative maintenance treatment.

The respective and interaction effects of spinal GRs and MRs on radicular pain induced by chronic compression of the dorsal root ganglion in the rat

High levels of glucocorticoid receptor (GR) and mineralocorticoid receptor (MR) are colocalized in the substantia gelatinosa. This indicates that the pain pathways appear to be under a strong regulation of these receptors. However, their respective effects on pain behaviors and their interaction remain unclear. Here we show that the nociceptive behaviors induced by chronic compression of the lumbar dorsal root ganglion (CCD) are attenuated by either GR agonist dexamethasone (4=2 μg>vehicle) or MR antagonist spironolactone (3 μg) administered intrathecally twice daily for postoperative days 2-4, whereas the GR antagonist mifepristone (2 μg) significantly exacerbated both mechanical hyperalgesia and thermal allodynia. Co-administration of spironolactone (3 μg) with dexamethasone (2 μg or 4 μg) twice daily on days 2-4 after CCD surgery produced positive synergistic effects. Moreover, different from intrathecally administered dexamethasone alone [no difference was found between two dose levels of dexamethasone (4 μg=2 μg)], dexamethasone suppresses mechanical allodynia and thermal hyperalgesia in a dose-dependent manner (4 μg>2 μg>vehicle) when combined with spironolactone (3 μg). These findings indicate that both central GRs and MRs play an important role in the regulation of pain behaviors and they have a perplexing interaction with each other. Spironolactone can enhance the analgesic effects of dexamethasone via complex mechanisms.

High pancreatic n-3 fatty acids prevent STZ-induced diabetes in fat-1 mice: inflammatory pathway inhibition

OBJECTIVE

Because of confounding factors, the effects of dietary n-3 polyunsaturated fatty acids (PUFA) on type 1 diabetes remain to be clarified. We therefore evaluated whether fat-1 transgenic mice, a well-controlled experimental model endogenously synthesizing n-3 PUFA, were protected against streptozotocin (STZ)-induced diabetes. We then aimed to elucidate the in vivo response at the pancreatic level.

RESEARCH DESIGN AND METHODS

β-Cell destruction was produced by multiple low-doses STZ (MLD-STZ). Blood glucose level, plasma insulin level, and plasma lipid analysis were then performed. Pancreatic mRNA expression of cytokines, the monocyte chemoattractant protein, and GLUT2 were evaluated as well as pancreas nuclear factor (NF)-κB p65 and inhibitor of κB (IκB) protein expression. Insulin and cleaved caspase-3 immunostaining and lipidomic analysis were performed in the pancreas.

RESULTS

STZ-induced fat-1 mice did not develop hyperglycemia compared with wild-type mice, and β-cell destruction was prevented as evidenced by lack of histological pancreatic damage or reduced insulin level. The prevention of β-cell destruction was associated with no proinflammatory cytokine induction (tumor necrosis factor-α, interleukin-1β, inducible nitric oxide synthase) in the pancreas, a decreased NF-κB, and increased IκB pancreatic protein expression. In the fat-1-treated mice, proinflammatory arachidonic-derived mediators as prostaglandin E₂ and 12-hydroxyeicosatetraenoic acid were decreased and the anti-inflammatory lipoxin A₄ was detected. Moreover, the 18-hydroxyeicosapentaenoic acid, precursor of the anti-inflammatory resolvin E1, was highly increased.

CONCLUSIONS

Collectively, these findings indicate that fat-1 mice were protected against MLD-STZ-induced diabetes and pointed out for the first time in vivo the beneficial effects of n-3 PUFA at the pancreatic level, on each step of the development of the pathology-inflammation, β-cell damage-through cytokine response and lipid mediator production.

Absence of NF-κB Activation by a New Polystyrene-Type Adsorbent Designed for Hemoperfusion

AIM

The aim of the study was to evaluate biocompatibility of anew polystyrene-type adsorbent (BetaSorb) designed for hemoperfusion, using second-level biomolecular analyses. The device has recently been developed to enhance beta2-microglobulin removal during hemodialysis. Molecular structure and chemical modifications of the surface beads of this cartridge should prevent exposure of dense hydrophobic surface sites to proteins, and avoid the major drawbacks of previous polystyrene-type adsorbent materials.

METHODS

Whole blood of healthy donors was incubated in sterile minicolumns packed with BetaSorb Cuprophan, Hemophan, polysulfone and cellulose acetate. In parallel experiments, whole blood was recirculated for 180 min in a sham dialysis circuit equipped with the study sorbent or Hemophan or polysulfone. Biocompatibility was assessed by means of new biomolecular approaches focused on nuclear factor kappaB (NF-kappaB) activation (assessed by electrophoretic mobility shift assay), TNF-alpha and IL-1beta gene expression (evaluated by real-time PCR), TNF-alpha and IL-1beta production (measured by Western blot assay and ELISA), nitric oxide (NO) generation (detected by electron paramagnetic resonance), free oxygen radical production (by chemiluminescence in a biological assay) and the generation of the complement breakdown product C3d.

RESULTS

In coincubation experiments, 5-min contact with any dialysis device, but BetaSorb, was enough to induce activation of NF-kappaB. The amount of TNF-alpha precursor form was found to increase after 5 min of exposure to each tested polymer, but no traces of mature forms of TNF-alpha or IL-1beta were detected in in vitro experimental conditions using healthy blood. NO and free oxygen radical generation were significantly lower in blood samples exposed to BetaSorb than in control dialysis devices. C3d levels were found to be increased with Hemophan, unaffected by polysulfone, and remarkably decreased with the BetaSorb device. In the sham hemodialysis experiments, NF-kappaB activation and C3d and NO profiles were similar to direct incubation experiments. Compared to basal levels, quantitation of TNF-alpha and IL-1beta mRNA revealed a 15- and 9-fold increase, respectively, in samples exposed to Hemophan for 180 min.

CONCLUSIONS

The new BetaSorb device not only appears to be highly biocompatible, but shares properties that make it probably able to interfere with the activation of the inflammatory state.

A synthetic hydroxypropenone inhibits nitric oxide, prostaglandin E2, and proinflammatory cytokine synthesis

HMP [3-(2-hydroxyphenyl)-1-(5-methyl-furan-2-y-l) propenone] was evaluated for its ability to inhibit the synthesis of major proinflammatory mediators and cytokines in interferon-gamma (IFN-gamma)- and lipopolysaccharide (LPS)-induced RAW 264.7 cells and phorbol myristate acetate (PMA)-differentiated/LPS-induced U937 cells. HMP suppressed the production of nitric oxide (NO) with significant inhibitory effects at doses as low as 0.78 microM (P < 0.05). Prostaglandin E2 (PGE2) secretion was also inhibited at doses of 12.5 microM and above (P < 0.01). The secretion of both TNF-alpha and IL-6 were only inhibited at the highest dose used (25 microM; P < 0.001). IL-1beta secretion was also inhibited from 12.5 microM onwards (P < 0.01). This inhibition was demonstrated to be caused by down-regulation of inducible enzymes, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), without direct effect upon iNOS or COX-2 enzyme activity. HMP only inhibited iNOS (P < 0.001) and IL-1beta (P < 0.05) gene expression at the highest tested concentration. HMP did not affect the secretion of chemokines IL-8 and monocyte chemotactic protein-1 (MCP-1) and the anti-inflammatory cytokine IL-10. The most striking effect of HMP was its NO inhibitory activity and therefore we conclude that HMP is a selective inhibitor of iNOS.

Chamomile: an anti-inflammatory agent inhibits inducible nitric oxide synthase expression by blocking RelA/p65 activity

Chamomile has long been used in traditional medicine for the treatment of inflammation-related disorders. In this study we investigated the inhibitory effects of chamomile on nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) expression, and explored its potential anti-inflammatory mechanisms using RAW 264.7 macrophages. Chamomile treatment inhibited LPS-induced NO production and significantly blocked IL-1β, IL-6 and TNFα-induced NO levels in RAW 264.7 macrophages. Chamomile caused reduction in LPS-induced iNOS mRNA and protein expression. In RAW 264.7 macrophages, LPS-induced DNA binding activity of RelA/p65 was significantly inhibited by chamomile, an effect that was mediated through the inhibition of IKKβ, the upstream kinase regulating NF-κB/Rel activity, and degradation of inhibitory factor-κB. These results demonstrate that chamomile inhibits NO production and iNOS gene expression by inhibiting RelA/p65 activation and supports the utilization of chamomile as an effective anti-inflammatory agent.

Nuclear factor-kappaB inducing kinase is required for graft-versus-host disease

BACKGROUND

Donor T lymphocytes are directly responsible for graft-versus-host disease. Molecules important in T-cell function may, therefore, be appropriate targets for graft-versus-host disease therapy and/or prophylaxis. Here we analyzed whether nuclear factor-κ B inducing kinase might have a role in graft-versus-host disease.

DESIGN AND METHODS

We studied the expression of nuclear factor-κ B inducing kinase in human samples from patients with graft-versus-host disease. We also explored the effect of nuclear factor-κ B inducing kinase in a murine model of graft-versus-host disease using donor cells from aly/aly mice (deficient in nuclear factor-κ B inducing kinase) and C57BL/6 mice (control).

RESULTS

We detected expression of nuclear factor-κ B inducing kinase in T-lymphocytes in the pathological lesions of patients with acute graft-versus-host disease. Mice transplanted with aly/aly T lymphocytes did not develop graft-versus-host disease at all, while mice receiving C57BL/6 cells died of a lethal form of the disease. Deficiency of nuclear factor-κ B inducing kinase did not affect the engrafting ability of donor T cells, but severely impaired their expansion capacity early after transplantation, and aly/aly T cells showed a higher proportion of apoptosis than did C57BL/6 T cells. Effector T lymphocytes were the T-cell subset most affected by nuclear factor-κ B inducing kinase deficiency. We also detected lower amounts of inflammatory cytokines in the serum of mice receiving aly/aly T cells than in the serum of mice receiving C57BL/6 T cells.

CONCLUSIONS

Our results show that nuclear factor-κ B inducing kinase has a role in graft-versus-host disease by maintaining the viability of activated alloreactive T lymphocytes.

Flowers of Inula japonica Attenuate Inflammatory Responses

Background

The flowers of Inula japonica (Inulae Flos) have long been used in traditional medicine for the treatment of inflammatory diseases. In the present study, we investigated the anti-inflammatory properties of Inulae Flos Extract (IFE).

Methods

The anti-inflammatory effects of IFE against nitric oxide (NO), PGE₂, TNF-α, and IL-6 release, as well as NF-κB and MAP kinase activation were evaluated in RAW 264.7 cells.

Results

IFE inhibited the production of NO and the expression of inducible nitric oxide synthase (iNOS) in LPS-stimulated RAW264.7 cells. In addition, IFE reduced the release of pro-inflammatory cytokines, such as TNF-α and IL-6. Furthermore, IFE inhibited the NF-κB activation induced by LPS, which was associated with the abrogation of IκB-α degradation and subsequent decreases in nuclear p65 and p50 levels. Moreover, the phosphorylation of ERK, JNK, and p38 MAP kinases in LPS-stimulated RAW 264.7 cells was suppressed by IFE in a dose-dependent manner.

Conclusion

These results suggest that the anti-inflammation activities of IFE might be attributed to the inhibition of NO, iNOS and cytokine expression through the down-regulation of NF-κB activation via suppression of IκBα and MAP kinase phosphorylation in macrophages.

Transduced PEP-1-ribosomal protein S3 (rpS3) ameliorates 12-O-tetradecanoylphorbol-13-acetate-induced inflammation in mice

This study investigated the preventive effect of ribosomal protein S3 (rpS3) on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ear edema in mice. A cell permeable expression vector PEP-1-rpS3 was constructed. Topical application of the vector markedly inhibited TPA-induced expression levels of cyclooxygenase-2 (COX-2) and pro-inflammatory cytokines. Application of PEP-1-rpS3 also resulted in a significant reduction in the activation of nuclear factor-kappa B (NF-kB) and mitogen-activated protein kinase (MAPK) in TPA-treated ears. These results indicate that PEP-1-rpS3 inhibits inflammatory response cytokines and enzymes by blocking NF-kB and MAPK, prompting the suggestion that PEP-1-rpS3 can be used as a therapeutic agent against skin inflammation.

Suppressive effects of extracts from the aerial part of Coriandrum sativum L. on LPS-induced inflammatory responses in murine RAW 264.7 macrophages

BACKGROUND

Coriandrum sativum is used not only as a spice to aid flavour and taste values in food, but also as a folk medicine in many countries. Since little is known about the anti-inflammatory ability of the aerial parts (stem and leaf) of C. sativum, the present study investigated the effect of aerial parts of C. sativum on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. We further explored the molecular mechanism underlying these pharmacological properties of C. sativum.

RESULTS

Ethanolic extracts from both stem and leaf of C. sativum (CSEE) significantly decreased LPS-induced nitric oxide and prostaglandin E(2) production as well as inducible nitric oxide synthase, cyclooxygenase-2, and pro-interleukin-1beta expression. Moreover, LPS-induced IkappaB-alpha phosphorylation and nuclear p65 protein expression as well as nuclear factor-kappaB (NF-kappaB) nuclear protein-DNA binding affinity and reporter gene activity were dramatically inhibited by aerial parts of CSEE. Exogenous addition of CSEE stem and leaf significantly reduced LPS-induced expression of phosphorylated mitogen-activated protein kinases (MAPKs).

CONCLUSION

Our data demonstrated that aerial parts of CSEE have a strong anti-inflammatory property which inhibits pro-inflammatory mediator expression by suppressing NF-kappaB activation and MAPK signal transduction pathway in LPS-induced macrophages.

Negative energy balance and hepatic gene expression patterns in high-yielding dairy cows during the early postpartum period: a global approach

In high-yielding dairy cows the liver undergoes extensive physiological and biochemical changes during the early postpartum period in an effort to re-establish metabolic homeostasis and to counteract the adverse effects of negative energy balance (NEB). These adaptations are likely to be mediated by significant alterations in hepatic gene expression. To gain new insights into these events an energy balance model was created using differential feeding and milking regimes to produce two groups of cows with either a mild (MNEB) or severe NEB (SNEB) status. Cows were slaughtered and liver tissues collected on days 6–7 of the first follicular wave postpartum. Using an Affymetrix 23k oligonucleotide bovine array to determine global gene expression in hepatic tissue of these cows, we found a total of 416 genes (189 up- and 227 downregulated) to be altered by SNEB. Network analysis using Ingenuity Pathway Analysis revealed that SNEB was associated with widespread changes in gene expression classified into 36 gene networks including those associated with lipid metabolism, connective tissue development and function, cell signaling, cell cycle, and metabolic diseases, the three most significant of which are discussed in detail. SNEB cows displayed reduced expression of transcription activators and signal transducers that regulate the expression of genes and gene networks associated with cell signaling and tissue repair. These alterations are linked with increased expression of abnormal cell cycle and cellular proliferation associated pathways. This study provides new information and insights on the effect of SNEB on gene expression in high-yielding Holstein Friesian dairy cows in the early postpartum period.

Polarized secretion of interleukin (IL)-6 and IL-8 by human airway epithelia 16HBE14o- cells in response to cationic polypeptide challenge

BACKGROUND

The airway epithelium participates in asthmatic inflammation in many ways. Target cells of the epithelium can respond to a variety of inflammatory mediators and cytokines. Damage to the surface epithelium occurs following the secretion of eosinophil-derived, highly toxic cationic proteins. Moreover, the surface epithelium itself is responsible for the synthesis and release of cytokines that cause the selective recruitment, retention, and accumulation of various inflammatory cells. To mimic the damage seen during asthmatic inflammation, the bronchial epithelium can be challenged with highly charged cationic polypeptides such as poly-L-arginine.

METHODOLOGY/PRINCIPAL FINDINGS

In this study, human bronchial epithelial cells, 16HBE14o- cells, were "chemically injured" by exposing them to poly-l-arginine as a surrogate of the eosinophil cationic protein. Cytokine antibody array data showed that seven inflammatory mediators were elevated out of the 40 tested, including marked elevation in interleukin (IL)-6 and IL-8 secretion. IL-6 and IL-8 mRNA expression levels were elevated as measured with real-time PCR. Cell culture supernatants from apical and basolateral compartments were collected, and the IL-6 and IL-8 production was quantified with ELISA. IL-6 and IL-8 secretion by 16HBE14o- epithelia into the apical compartment was significantly higher than that from the basolateral compartment. Using specific inhibitors, the production of IL-6 and IL-8 was found to be dependent on p38 MAPK, ERK1/2 MAPK, and NF-kappaB pathways.

CONCLUSIONS/SIGNIFICANCE

The results clearly demonstrate that damage to the bronchial epithelia by poly-L-arginine stimulates polarized IL-6 and IL-8 secretion. This apically directed secretion of cytokines may play an important role in orchestrating epithelial cell responses to inflammation.

Understanding the role of aldose reductase in ocular inflammation

Aldose reductase, although identified initially as a glucose-reducing enzyme via polyol pathway, is believed to be an important component of antioxidant defense system as well as a key mediator of oxidative stress-induced molecular signaling. The dual role played by AR has made it a very important enzyme for the regulation of not only the cellular redox state by detoxifying the reactive lipid-aldehydes generated by lipid peroxidation which is crucial in the cellular homeostasis, but also in the regulation of molecular signaling cascade that may regulate oxidative stress-induced cytotoxic events. Search for the new molecular targets to restrain the oxidative stress-induced inflammation has resulted in the identification of AR as an unanticipated mediator of oxidative stress-induced signaling. Although, in last one decade or so AR has been implicated in various inflammation-related diseases conditions ranging from diabetes, sepsis, cancer, cardiovascular and ocular inflammation, however, a critical evaluation of the clinical efficacy of AR inhibitors awaits a better understanding of the role of AR in regulating inflammation, especially in ocular inflammation.

Atrovirinone inhibits proinflammatory mediator synthesis through disruption of NF-kappaB nuclear translocation and MAPK phosphorylation in the murine monocytic macrophage RAW 264.7

In a previous communication we showed that atrovirinone, a 1,4-benzoquinone isolated from the roots of Garcinia atroviridis, was able to inhibit several major proinflammatory mediators of inflammation. In this report we show that atrovirinone inhibits NO and PGE(2) synthesis through inhibition of iNOS and COX-2 expression. We also show that atrovirinone inhibits the secretion of IL-1beta and IL-6 in a dose dependent fashion whereas the secretion of IL-10, the anti-inflammatory cytokine, was enhanced. Subsequently we determined that the inhibition of proinflammatory cytokine synthesis and inducible enzyme expression was due to a dose-dependent inhibition of phosphorylation of p38 and ERK1/2. We also showed that atrovirinone prevented phosphorylation of I-kappaBalpha, which resulted in a reduction of p65NF-kappaB nuclear translocation as demonstrated by expression analysis. We conclude that atrovirinone is a potential anti-inflammatory drug lead that targets both the MAPK and NF-kappaB pathway.

Inhibitor IkappaBalpha promoter functional polymorphisms in patients with rheumatoid arthritis

INTRODUCTION

Rheumatoid arthritis (RA) is a chronic inflammation disease that may involve extra-articular organs in addition to joints. Many proinflammatory cytokines are involved in the inflammatory process of RA. IkappaBalpha conjugates with NF-kappaB and is a key player in regulation of the inflammatory process. We carried out experiments to define the effect of different promoter polymorphisms on the transcriptional activities of IkappaBalpha promoter and the development of RA.

METHODS

Different IkappaBalpha promoter reporters were constructed and were examined in human mononuclear cells, THP-1 cells. One hundred forty patients and 115 healthy controls were recruited from the Kaohsiung Medical University Hospital.

RESULTS

The activities of IkappaBalpha promoter constructs with -826C, -550A, -519T, and -826T, -550A, -519T genotypes were expressed at one half the activity level of other constructs. Promoter constructs containing the sites -550A/T and -519T had a reduced risk of rheumatoid arthritis. The odds ratio of -826C/T genotype was significantly associated with an increase of risk in causing rheumatoid arthritis, whereas -826T/T genotype was associated only with a slightly increased risk of RA, but without statistical significance (odds ratio = 1.2; 95% confidence interval, 0.4-3.8).

CONCLUSION

The increase of T allele was associated with a significant increased risk and the tendency to the pathogenesis of RA. The association between IkappaBalpha promoter polymorphisms and disease severity of rheumatoid arthritis is partly due to different transcriptional activities of IkappaBalpha promoter and the activation of NF-kappaB.

2'-Methoxy-4'6'-bis(methoxymethoxy)chalcone inhibits nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 macrophages

Chalcones have anti-inflammatory properties. Here, we synthesized 2'-methoxy-4'6'-bis(methoxymethoxy)chalcone (MBMC) and examined its anti-inflammatory effects. MBMC inhibited nitric oxide production and inducible nitric oxide synthase (iNOS) expression in lipopolysaccharide (LPS)-stimulated RAW 264.7 murine macrophages. MBMC also blocked LPS-induced activation of nuclear factor kappaB (NF-kappaB), p38 mitogen-activated protein kinase and c-Jun N-terminal kinase (JNK). MBMC increased haem oxygenase 1 (HO-1) expression and nuclear accumulation of nuclear factor-erythroid 2-related factor 2 (Nrf2), an essential transcription factor for HO-1 induction. Treatment with tin protoporphyrin, a selective inhibitor of HO-1, reversed the inhibition of nitric oxide production by MBMC, suggesting that HO-1 induction mediates MBMC-mediated suppression of nitric oxide production. MBMC treatment rapidly and transiently decreased glutathione (GSH) levels, and treatment with GSH-Et (cell permeable form of GSH) or N-acetylcysteine (precursor of GSH) counteracted the HO-1 and Nrf2 expression elicited by MBMC, indicating that MBMC-induced HO-1 expression requires transient depletion of GSH. In summary, MBMC inhibits LPS-stimulated nitric oxide production via down-regulation of inflammatory pathways (NF-kappaB, p38 and JNK) and induction of the protective enzyme, HO-1.

Differential cytokine regulation by NF-kappaB and AP-1 in Jurkat T-cells

Background

Activator protein (AP)-1 and nuclear factor (NF)-κB largely control T-cell activation, following binding of foreign antigens to the T-cell receptor leading to cytokine secretion. Elevated levels of pro-inflammatory cytokines and chemokines such as TNF, IL-6 and CXCL8 are associated with several human diseases including cystic fibrosis, pulmonary fibrosis and AIDS. The aim of this study was to investigate the role of the transcription factors, AP-1 and NF-κB, in IL-6 and CXCL8 regulation in Jurkat T-cells.

Results

Phorbol myristate acetate (PMA) exposure resulted in an up-regulation of AP-1 and down-regulation of NF-κB activity, however, exposure to heat killed (HK) Escherichia. coli MG1655 resulted in a dose-dependent increase in NF-κB activity without affecting AP-1. The cytokine profile revealed an up-regulation of the chemokine CXCL8 and the pro-inflammatory cytokines TNF, IL-2 and IL-6 following treatment with both PMA and HK E. coli, while the levels of the anti-inflammatory cytokine IL-10 were not affected by PMA but were significantly down-regulated by HK E. coli. AP-1 activation was significantly increased 2 h after PMA exposure and continued to increase thereafter. In contrast, NF-κB responded to PMA exposure by a rapid up-regulation followed by a subsequent down-regulation. Increased intracellular Ca²⁺ concentrations countered the down-regulation of NF-κB by PMA, while similar treatment with calcium ionophore resulted in a reduced NF-κB activity following induction with HK E. coli. In order to further study NF-κB activation, we considered two up-stream signalling proteins, PKC and Bcl10. Phosphorylated-PKC levels increased in response to PMA and HK E. coli, while Bcl10 levels significantly decreased following PMA treatment. Using an NF-κB activation inhibitor, we observed complete inhibition of IL-6 expression while CXCL8 levels only decreased by 40% at the highest concentration. Treatment of Jurkat T-cells with PMA in the presence of JNK-inhibitor suppressed both CXCL8 and IL-6 while PKC-inhibitor primarily decreased CXCL8 expression.

Conclusion

The present study shows that NF-κB regulated IL-6 but not CXCL8. This complex regulation of CXCL8 suggests that there is a need to further evaluate the signalling pathways in order to develop new treatment for diseases with elevated CXCL8 levels, such as AIDS and autoimmune diseases.

Immunostimulatory Effects of Cordyceps militaris on Macrophages through the Enhanced Production of Cytokines via the Activation of NF-kappaB

Background

Cordyceps militaris has been used in traditional medicine to treat numerous diseases and has been reported to possess both antitumor and immunomodulatory activities in vitro and in vivo. However, the pharmacological and biochemical mechanisms of Cordyceps militaris extract (CME) on macrophages have not been clearly elucidated. In the present study, we examined how CME induces the production of proinflammatory cytokines, transcription factor, and the expression of co-stimulatory molecules.

Methods

We confirmed the mRNA and protein levels of proinflammatory cytokines through RT-PCR and western blot analysis, followed by a FACS analysis for surface molecules.

Results

CME dose dependently increased the production of NO and proinflammatory cytokines such as IL-1β, IL-6, TNF-α, and PGE₂, and it induced the protein levels of iNOS, COX-2, and proinflammatory cytokines in a concentration-dependent manner, as determined by western blot and RT-PCR analysis, respectively. The expression of co-stimulatory molecules such as ICAM-1, B7-1, and B7-2 was also enhanced by CME. Furthermore, the activation of the nuclear transcription factor, NF-κB in macrophages was stimulated by CME.

Conclusion

Based on these observations, CME increased proinflammatory cytokines through the activation of NF-κB, further suggesting that CME may prove useful as an immune-enhancing agent in the treatment of immunological disease.

Potential use of iontophoresis for transdermal delivery of NF-kappaB decoy oligonucleotides

Topical application of nuclear factor-kappaB (NF-kappaB) decoy appears to provide a novel therapeutic potency in the treatment of inflammation and atopic dermatitis. However, it is difficult to deliver NF-kappaB decoy oligonucleotides (ODN) into the skin by conventional methods based on passive diffusion because of its hydrophilicity and high molecular weight. In this study, we evaluated the in vitro transdermal delivery of fluorescein isothiocyanate (FITC)-NF-kappaB decoy ODN using a pulse depolarization (PDP) iontophoresis. In vitro iontophoretic experiments were performed on isolated C57BL/6 mice skin using a horizontal diffusion cell. The apparent flux values of FITC-NF-kappaB decoy ODN were enhanced with increasing the current density and NF-kappaB decoy ODN concentration by iontophoresis. Accumulation of FITC-NF-kappaB decoy ODN was observed at the epidermis and upper dermis by iontophoresis. In mouse model of skin inflammation, iontophoretic delivery of NF-kappaB decoy ODN significantly reduced the increase in ear thickness caused by phorbol ester as well as the protein and mRNA expression levels of tumor necrosis factor-alpha (TNF-alpha) in the mice ears. These results suggest that iontophoresis is a useful and promising enhancement technique for transdermal delivery of NF-kappaB decoy ODN.

Red clover extract: a source for substances that activate peroxisome proliferator-activated receptor alpha and ameliorate the cytokine secretion profile of lipopolysaccharide-stimulated macrophages

OBJECTIVE

Inflammation and hyperlipidemia or dyslipidemia contribute to an increased risk of atherosclerosis and cardiovascular disease. Cardiovascular disease represents one of the major causes of premature death worldwide. The activation of peroxisome proliferator-activated receptor (PPAR) alpha, a drug target for hyperlipidemia and dyslipidemia, leads to an improved blood lipid profile. In this study, we determined the putative anti-inflammatory and PPARalpha stimulatory activities of red clover, an alternative to the classic hormone therapy used currently to treat menopausal symptoms.

METHODS

Lipopolysaccharide-induced macrophages were used as a model for anti-inflammatory activity, and a chimeric GAL4-PPARalpha system was used as a model for putative hypolipidemic activity.

RESULTS

Red clover extract and the isoflavones genistein and biochanin A were moderate PPARalpha activators. Daidzein only slightly activated PPARalpha, but its metabolite 6-hydroxydaidzein exerted a much higher PPARalpha activity. Similarly, the metabolite 3'-hydroxygenistein achieved higher activation efficiency than its precursor, genistein, did. In lipopolysaccharide-stimulated macrophages, red clover extract and its compounds reduced the secretion of proinflammatory cytokines, interleukin-6 and tumor necrosis factor alpha, increased the secretion of the anti-inflammatory interleukin-10, and/or reduced the expression of nuclear factor-kappaB, inducible nitric oxide synthase, and/or cyclooxygenase 2. Tumor necrosis factor alpha production was most efficiently reduced by biochanin A and genistein. Interleukin-6 levels were most efficiently reduced by genistein and equol.

CONCLUSIONS

Owing to its PPARalpha activation and modulation of the secreted cytokine profile, red clover extract is a putative candidate for preventing atherosclerosis and, thus, cardiovascular disease.

Toll-like receptor 4 signaling promotes tumor growth

Chronic inflammation is a potential risk factor for tumor progression. The molecular mechanisms linking chronic inflammation and tumor growth have proven elusive. Herein, we describe a new role for Toll-like receptor 4 (TLR4) in tumor-associated macrophages (TAMs) in promoting tumor growth. TAMs can remodel tumor microenvironment and promote tumor growth. With the use of mice lacking TLR4 signaling, we show that TLR4 signaling influences tumor growth and that TLR4 signaling is a critical upstream activator of nuclear factor-kappa B (NF-kappaB) in TAMs. TLR4-deficient TAMs produce neither proinflammatory cytokines nor angiogenic factors, and activate no NF-kappaB activity in tumor cells. Furthermore, using macrophage/tumor cell coculture system and adoptive transfer of macrophages with functional TLR4 macrophages to TLR4-deficient mice bearing tumors, we demonstrate an essential role for TLR4 signaling in inducing NF-kappaB activity in tumor cells and enhancing tumor growth. Antibody neutralization experiments reveal that TAMs are stimulated by heat shock proteins derived from tumor cells through TLR4, leading to production of growth factors, which may in turn promote tumor growth via NF-kappaB signal pathway. Therefore, this signaling cascade may represent a therapeutic target in cancer.

Potential health-modulating effects of isoflavones and metabolites via activation of PPAR and AhR

Isoflavones have multiple actions on cell functions. The most prominent one is the activation of estrogen receptors. Other functions are often overlooked, but are equally important and explain the beneficial health effects of isoflavones. Isoflavones are potent dual PPARα/γ agonists and exert anti-inflammatory activity, which may contribute to the prevention of metabolic syndrome, atherosclerosis and various other inflammatory diseases. Some isoflavones are potent aryl hydrocarbon receptor (AhR) agonists and induce cell cycle arrest, chemoprevention and modulate xenobiotic metabolism. This review discusses effects mediated by the activation of AhR and PPARs and casts a light on the concerted action of isoflavones.

The challenge of antioxidants to free radicals in periodontitis

Periodontal disease is a chronic adult condition. Bacteria implicated in the etiology of this disease causes destruction of connective tissue and bone. As a result of stimulation by bacterial antigen PMN produces free radicals via respiratory burst as a part of host response to infection. Patients with periodontal disease display increased PMN number and activity. This proliferation results in high degree of free radical release culminating in heightened oxidative damage to gingival tissues, periodontal ligament and alveolar bone. Damage mediated by free radicals can be mitigated by “ANTIOXIDANT DEFENSE SYSTEM “. Physiological alteration and pathological states produced by free radicals depend on disequilibrium between free radical production and antioxidant levels leading to oxidative stress.

Hence this study has been designed to estimate the TOTAL ANTIOXIDANT CAPACITY in patients with PERIODONTITIS and healthy control subjects

Tetrandrine attenuates lipopolysaccharide-induced fulminant hepatic failure in D-galactosamine-sensitized mice

Fulminant hepatic failure (FHF) remains an extremely poor prognosis and high mortality; better treatments are urgently needed. Tetrandrine (TET), a traditional anti-inflammatory drug, has been reported to exhibit hepatoprotective activities in several liver injury models. We now investigated the effects and underlying mechanisms of TET on lipopolysaccharide (LPS) and D-galactosamine (D-GalN)-induced FHF in mice. TET (50, 100, and 200 mg/kg) was given intraperitoneally 1h before LPS/D-GalN injection in mice. The mortality and liver injury was evaluated subsequently. The results showed that administering TET to mice reduced mortality and improved liver injury induced by LPS/D-GalN in a dose-dependent manner. In addition, TET dose-dependently inhibited LPS/D-GalN-induced NF-kappaB activation, serum and hepatic tissues tumor necrosis factor-alpha (TNF-alpha) production, caspase-3 activation and hepatocellular apoptosis, myeloperoxidase (MPO) activity, intercellular adhesion molecule-1 (ICAM-1) and endothelial cell adhesion molecule-1 (ECAM-1) expression. Our experimental data indicated that TET might alleviate the FHF induced by LPS/D-GalN through inhibiting NF-kappaB activation to reduce TNF-alpha production.

Intracellular signaling mechanisms regulating the activation of human eosinophils by the novel Th2 cytokine IL-33: implications for allergic inflammation

The novel interleukin (IL)-1 family cytokine IL-33 has been shown to activate T helper 2 (Th2) lymphocytes, mast cells and basophils to produce an array of proinflammatory cytokines, as well as to mediate blood eosinophilia, IgE secretion and hypertrophy of airway epithelium in mice. In the present study, we characterized the activation of human eosinophils by IL-33, and investigated the underlying intracellular signaling mechanisms. IL-33 markedly enhanced eosinophil survival and upregulated cell surface expression of the adhesion molecule intercellular adhesion molecule (ICAM)-1 on eosinophils, but it suppressed that of ICAM-3 and L-selectin. In addition, IL-33 mediates significant release of the proinflammatory cytokine IL-6 and the chemokines CXCL8 and CCL2. We found that IL-33-mediated enhancement of survival, induction of adhesion molecules, and release of cytokines and chemokines were differentially regulated by activation of the nuclear factor (NF)-kappaB, p38 mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinase (ERK) pathways. Furthermore, we compared the above IL-33 activities with two structurally and functionally related cytokines, IL-1beta and IL-18. IL-1beta, but not IL-18, markedly upregulated cell surface expression of ICAM-1. IL-1beta and IL-18 also significantly enhanced eosinophil survival, and induced the release of IL-6 and chemokines CXCL8 and CCL2 via the activation of the NF-kappaB, p38 MAPK and ERK pathways. Synergistic effects on the release of IL-6 were also observed in combined treatment with IL-1beta, IL-18 and IL-33. Taken together, our findings provide insight into IL-33-mediated activation of eosinophils via differential intracellular signaling cascades in the immunopathogenesis of allergic inflammation.

Identification of a small molecule inhibitor of serine 276 phosphorylation of the p65 subunit of NF-kappaB using in silico molecular docking

NF-kappaB is activated in many types of cancer. Phosphorylation of p65 at serine 276 is required for the expression of a subset of NF-kappaB regulated genes, including vascular cell adhesion molecule-1 (VCAM-1) and interleukin-8 (IL-8). Thus, inhibition of serine 276 phosphorylation may prevent metastasis and angiogenesis in certain tumor types. Using in silico molecular docking, small molecules that are predicted to bind to a structural pocket near serine 276 were identified. One compound, NSC-127102, hinders serine 276 phosphorylation and the expression of IL-8 and VCAM-1. Small molecules such as NSC-127102 may be optimized for the future treatment of cancer.

Flow-Mediated Signaling Modulates Endothelial Cell Phenotype

The focal development of atherosclerosis in the vascular tree may be explained in part by the local nature of blood flow. Bifurcations and branching points, prone to early atherogenesis, experience disturbed and oscillatory flow, whereas straight vascular regions, resistant to atherosclerosis, are exposed to steady laminar flow. A large number of studies suggest that the antiatherosclerotic effects of laminar flow are in part due to the ability of flow to modulate endothelial cell phenotype. Under steady laminar flow, endothelial cells generate molecules that promote a vasoactive, anticoagulant, anti-inflammatory, and growth-inhibitory surface. In contrast, disturbed flow induces a proliferative, prothrombotic, and adhesive phenotype. Endothelial cells are able to sense the variations of flow via mechanosensitive cell surface proteins and to transduce these signals via intracellular pathways to transcription factors in the nucleus leading to phenotypic changes. This review summarizes the "outside-in" signaling events initiated by flow that modulate endothelial cell phenotype.