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

A Dual Noradrenergic Mechanism for the Relief of Neuropathic Allodynia by the Antidepressant Drugs Duloxetine and Amitriptyline

In addition to treating depression, antidepressant drugs are also a first-line treatment for neuropathic pain, which is pain secondary to lesion or pathology of the nervous system. Despite the widespread use of these drugs, the mechanism underlying their therapeutic action in this pain context remains partly elusive. The present study combined data collected in male and female mice from a model of neuropathic pain and data from the clinical setting to understand how antidepressant drugs act. We show two distinct mechanisms by which the selective inhibitor of serotonin and noradrenaline reuptake duloxetine and the tricyclic antidepressant amitriptyline relieve neuropathic allodynia. One of these mechanisms is acute, central, and requires descending noradrenergic inhibitory controls and α_2A adrenoceptors, as well as the mu and delta opioid receptors. The second mechanism is delayed, peripheral, and requires noradrenaline from peripheral sympathetic endings and β₂ adrenoceptors, as well as the delta opioid receptors. We then conducted a transcriptomic analysis in dorsal root ganglia, which suggested that the peripheral component of duloxetine action involves the inhibition of neuroimmune mechanisms accompanying nerve injury, including the downregulation of the TNF-α-NF-κB signaling pathway. Accordingly, immunotherapies against either TNF-α or Toll-like receptor 2 (TLR2) provided allodynia relief. We also compared duloxetine plasma levels in the animal model and in patients and we observed that patients' drug concentrations were compatible with those measured in animals under chronic treatment involving the peripheral mechanism. Our study highlights a peripheral neuroimmune component of antidepressant drugs that is relevant to their delayed therapeutic action against neuropathic pain.SIGNIFICANCE STATEMENT In addition to treating depression, antidepressant drugs are also a first-line treatment for neuropathic pain, which is pain secondary to lesion or pathology of the nervous system. However, the mechanism by which antidepressant drugs can relieve neuropathic pain remained in part elusive. Indeed, preclinical studies led to contradictions concerning the anatomical and molecular substrates of this action. In the present work, we overcame these apparent contradictions by highlighting the existence of two independent mechanisms. One is rapid and centrally mediated by descending controls from the brain to the spinal cord and the other is delayed, peripheral, and relies on the anti-neuroimmune action of chronic antidepressant treatment.

Dietary n-3 but not n-6 fatty acids down-regulate maternal dyslipidemia induced inflammation: A three-generation study in rats

This study addresses the effects of n-3 and n-6 fatty acids in maternal dyslipidemia induced inflammation over three generation in rats. The detailed protocol for animal feeding and mating is described in the methodology. Placenta and fetal liver were isolated on the eighteenth day of gestation and delivered pups after lactation were kept on their maternal diets. Compared to control and experimental groups, high-fat fed rats (HFL) had a higher level of cytokines and eicosanoids in serum (p < 0.05). Liver and uterine expression of cPLA-2, Cox-2, 5-Lox, EP-1, BLT-1, and ICAM-1 were higher (p < 0.05) in HFL group. NF-kB and Nrf-2 levels in placenta and fetal liver were beneficially modulated by n-3 but not n-6 fatty acids. Offspring of dyslipidemic mothers' exhibit amplified inflammatory markers when continued on diets of their mothers. Incorporation of n-3 but not n-6 fatty acids down-regulated maternal dyslipidemia induced inflammatory markers.

Momordica charantia Inhibits Inflammatory Responses in Murine Macrophages via Suppression of TAK1

Momordica charantia known as bitter melon is a representative medicinal plant reported to exhibit numerous pharmacological activities such as antibacterial, antidiabetic, anti-inflammatory, anti-oxidant, antitumor, and hypoglycemic actions. Although this plant has high ethnopharmacological value for treating inflammatory diseases, the molecular mechanisms by which it inhibits the inflammatory response are not fully understood. In this study, we aim to identify the anti-inflammatory mechanism of this plant. To this end, we studied the effects of its methanol extract (Mc-ME) on lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Specifically, we evaluated nitric oxide (NO) production, mRNA expression of inflammatory genes, luciferase reporter gene activity, and putative molecular targets. Mc-ME blocked NO production in a dose-dependent manner in RAW264.7 cells; importantly, no cytotoxicity was observed. Moreover, the mRNA expression levels of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 were decreased by Mc-ME treatment in a dose-dependent manner. Luciferase assays and nuclear lysate immunoblotting analyses strongly indicated that Mc-ME decreases the levels of p65 [a nuclear factor (NF)-[Formula: see text]B subunit] and c-Fos [an activator protein (AP)-1 subunit]. Whole lysate immunoblotting assays, luciferase assays, and overexpression experiments suggested that transforming growth factor [Formula: see text]-activated kinase 1 (TAK1) is targeted by Mc-ME, thereby suppressing NF-[Formula: see text]B and AP-1 activity via downregulation of extracellular signal-regulated kinases (ERKs) and AKT. These results strongly suggest that Mc-ME exerts its anti-inflammatory activity by reducing the action of TAK1, which also affects the activation of NF-[Formula: see text]B and AP-1.

Serum containing Gengnianchun formula suppresses amyloid β‑induced inflammatory cytokines in BV‑2 microglial cells by inhibiting the NF‑κB and JNK signaling pathways

As the resident macrophages of the brain's innate immune system, microglial cells are key modulators in the neurodegenerative disease Alzheimer's disease (AD). In particular, the activation and accumulation of microglial cells around amyloid plaques is considered to result in chronic neuroinflammation. Although the pathologic mechanism remains to be fully elucidated, inflammation has been shown to be critical in the pathogenesis of AD. The Gengnianchun (GNC) formula has long been used to treat perimenopausal syndrome clinically, and is particularly effective in improving learning ability and memory. Our previous study demonstrated that GNC formula had an anti-inflammatory effect and offered neuroprotection in animal experiments. In the present study, the anti-inflammatory properties of GNC and its underlying mechanism of action were examined in BV-2 microglial cells. Amyloid-β peptide (Aβ)-stimulated microglial cells were examined for the production of proinflammatory cytokines and the underlying signaling pathways. Compared with the normal control group, the protein expression levels of IL-1β and TNF-α were significantly increased following treatment with Aβ (P<0.01), but medicated rat serum containing GNC formula (MRS) could significantly attenuated the Aβ-induced secretion of these pro-inflammatory cytokines. It was identified by CCK-8 assay that the viability of the BV-2 cells was not reduced following treatment with various concentrations of MRS. The phosphorylation of factor-κB (NF-κB) and c-Jun N-terminal kinase (JNK) was markedly increased following treatment with Aβ, compared with the normal control group (P<0.01). However, treatment with MRS resulted in a significant reduction in the phosphorylation of NF-κB (P<0.05). These results suggested that MRS suppressed the Aβ-induced inflammatory response of microglial cells by inhibiting the NF-κB and JNK signaling pathways. These novel findings provide insights into the development of GNC formula as a therapeutic agent for the treatment of neurodegenerative disorders.

Anti-Inflammatory Effects of a Stauntonia hexaphylla Fruit Extract in Lipopolysaccharide-Activated RAW-264.7 Macrophages and Rats by Carrageenan-Induced Hind Paw Swelling

The fruit of Stauntonia hexaphylla is commonly used as a traditional anthelmintic in Korea, Japan, and China. However, its anti-inflammatory activity and the underlying mechanisms have not been studied systematically. In the present study, we examined the anti-inflammatory activities of an aqueous extract of S. hexaphylla fruit (SHF) in lipopolysaccharide (LPS)-activated RAW 264.7 cells. The SHF extract contained anti-inflammatory compounds, such as neochlorogenic acid, chlorogenic acid, and cryptochlorogenic acid. The extract inhibited protein levels of inducible nitric oxide synthase and the activity of cyclooxygenase enzyme, with concomitant reductions in the production of nitric oxide and prostaglandin E₂ in LPS-activated RAW 264.7 cells. Additionally, the SHF extract reduced the production of pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin (IL)-1β, and IL-6. The SHF extract attenuated LPS-induced nuclear factor-κB (NF-κB) activation by decreasing the phosphorylation of its inhibitor, IκBα. Furthermore, the SHF extract showed a significant anti-inflammatory effect in vivo by reducing the volume of carrageenan-induced paw edema in rats. Our results suggest that the SHF extract exerts potential anti-inflammatory properties against LPS-activated RAW 254.7 cells, and in an animal model of inflammation.

Presenting a New Standard Drug Model for Turmeric and Its Prized Extract, Curcumin

Various parts of the turmeric plant have been used as medicinal treatment for various conditions from ulcers and arthritis to cardiovascular disease and neuroinflammation. The rhizome's curcumin extract is the most studied active constituent, which exhibits an expansive polypharmacology with influence on many key inflammatory markers. Despite the expansive reports of curcucmin's therapeutic value, clinical reliability and research repeatability with curcumin treatment are still poor. The pharmacology must be better understood and reliably mapped if curcumin is to be accepted and used in modern medical applications. Although the polypharmacology of this extract has been considered, in mainstream medicine, to be a drawback, a perspective change reveals a comprehensive and even synergistic shaping of the NF-kB pathway, including transactivation. Much of the inconsistent research data and unreliable clinical outcomes may be due to a lack of standardization which also pervades research standard samples. The possibility of other well-known curcumin by-products contributing in the polypharmacology is also discussed. A new flowchart of crosstalk in transduction pathways that lead to shaping of nuclear NF-kB transactivation is generated and a new calibration or standardization protocol for the extract is proposed which could lead to more consistent data extraction and improved reliability in therapy.

The sneaking ligand approach for cell type-specific modulation of intracellular signalling pathways

Small molecules interfering with intracellular signalling pathways are used in the treatment of multiple diseases including RA. However, small molecules usually affect signalling in most cell types, not only in those which need to be targeted. This general inhibition of signalling pathways causes often adverse effects, which could be avoided by cell type-specific inhibitors. For cell-type specific modulation of signal transduction, we developed the sneaking ligand fusion proteins (SLFPs). SLFPs contain three domains: (1) the binding domain mediating cell type-specific targeting and endocytosis; (2) the endosomal release sequence releasing the effector domain into the cytoplasm; (3) the effector domain modulating signalling. Using our SLFP NF-kappaB inhibitor termed SLC1 we demonstrated that cell-type-specific modulation of intracellular signalling pathways is feasible, that endothelial NF-kappaB activation is critical for arthritis and peritonitis and that SLFPs help to identify disease-relevant pathways in defined cell types. Hence, SLFPs may improve risk-benefit ratios of therapeutic interventions.

Anti-inflammatory effect and mechanism of action of Lindera erythrocarpa essential oil in lipopolysaccharide-stimulated RAW264.7 cells

The aim of this study was to investigate the chemical constituents of Lindera erythrocarpa essential oil (LEO) by gas chromatography-mass spectrometry and evaluate their inhibitory effect on the expression of pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Fifteen compounds, accounting for 63.7 % of the composition of LEO, were identified. The main compounds were nerolidol (18.73 %), caryophyllene (14.41 %), α-humulene (7.73 %), germacrene-D (4.82 %), and α-pinene (4.47 %). LEO significantly inhibited the expression of inducible nitric oxide (NO) synthase and cyclooxygenase-2, and subsequent production of NO and prostaglandin E₂. In addition, it reduced the release of pro-inflammatory cytokines in LPS-activated RAW264.7 cells. The molecular mechanism underlying the effect of LEO was associated with inhibition of the phosphorylation of mitogen-activated protein kinase (MAPK). Furthermore, LEO inhibited LPS-induced phosphorylation and degradation of inhibitor of kappa B-α, which is required for the activation of the p50 and p65 nuclear factor (NF)-κB subunits in RAW264.7 cells. Taken together, these data suggest that LEO exerted its anti-inflammatory effect by downregulating LPS-induced production of pro-inflammatory mediators through the inhibition of NF-κB and MAPK signaling in RAW264.7 cells.

The Impact of Synovial NF-κB Activation on Apoptosis Pattern Change During Adjuvant-induced Inflammation

Introduction:

Apoptosis dysregulation plays a substantial role in the pathophysiology of chronic inflammation and its related symptoms such as edema. Regulation of NF-κB activation is involved in apoptosis pattern change. The current study aimed at verifying the effects of local inflammation on edema and changes in apoptotic markers, and investigating the possible role of NF-κB in apoptosis pattern change during different stages of complete Freund’s adjuvant (CFA)-induced knee arthritis in rats.

Methods:

A total of 96 male Wistar rats were divided into different experimental groups. Arthritis was evoked into the right knee articular joint. Changes made in knee edema were assessed by caliper on the days 0, 7, 14, and 21 of the study. Synovial NF-κB and levels of apoptotic markers were evaluated during different stages of the study using Western blot technique.

Results:

CFA injection caused intense edema during the whole study period. Synovial NF-κB level increased during the whole study period. The level of apoptotic markers increased during the acute phase of study. But during chronic phase, the apoptosis level decreased. Inh-NF-κB administration increased synovial apoptosis during the whole study period.

Conclusion:

It seems that apoptosis pattern change plays an important role in the progression and modulation of CFA-induced inflammation and its related symptoms. Also, it can be concluded that synovial NF-κB had a crucial role in synovial apoptosis change during the study period.

Methamphetamine causes neurotoxicity by promoting polarization of macrophages and inflammatory response

Macrophages, especially their activation state, are closely related to the progression of neurotoxicity. Classically activated macrophages (M1) are proinflammatory effectors, while alternatively activated macrophages (M2) exhibit anti-inflammatory properties. As a powerful addictive psychostimulant drug, coupled with its neurotoxicity, methamphetamine (Meth) abuse may lead to long-lasting abnormalities in the neuronal system. The present study investigated the effect of Meth at subtoxic concentration on macrophage activation state and its underlying toxicity to neuronal cells. PC12 and Murine RAW264.7 cells were coincubated with Meth to test its toxicity. 3-(4,5-Dimethylthiazol)-2,5-diphenyltetrazolium-bromide, enzyme-linked immunosorbent assay, real-time polymerase chain reaction, and Western blot assays were performed to evaluate the toxicity, cytokine secretion, gene, and protein expression. Results showed that cytotoxicity was enhanced on PC12 cells after coculturing with RAW264.7 stimulated with Meth. RAW264.7 macrophages tended to switch to the M1 phenotype, releasing more nitric oxide and proinflammatory cytokines, including tumor necrosis factor α (TNFα), interleukin (IL)-12, and IL-1β, while decreasing the release of anti-inflammatory cytokine IL-10 after treatment with Meth. Meth upregulated the gene expression of IL-6, IL-1β, and TNFα and downregulated the expression of Arg-1, IL-10, and KLF4. Meth could also upregulate the protein expression of IL-1β and TNF α and downregulate the expression of Arg-1 and KLF4. However, the abovementioned effects induced by Meth were abolished by the addition of dopamine receptor D3 antagonist. In conclusion, our study demonstrated that Meth promoted macrophage polarization from M0 to M1 and enhanced inflammatory response, which provided the scientific rationale for the neurotoxicity caused by the chronic use of Meth.

Arsenic affects inflammatory cytokine expression in Gallus gallus brain tissues

Background

The heavy metal arsenic is widely distributed in nature and posses a serious threat to organism’s health. However, little is known about the arsenic-induced inflammatory response in the brain tissues of birds and the relationship and mechanism of the inflammatory response. The purpose of this study was to explore the effects of dietary arsenic on the expression of inflammatory cytokines in the brains of Gallus gallus.

Results

Seventy-two 1-day-old male Hy-line chickens were divided into a control group, a low arsenic trioxide (As₂O₃)-treated (7.5 mg/kg) group, a middle As₂O₃-treated (15 mg/kg) group, and a high As₂O₃-treated (30 mg/kg) group. Arsenic exposure caused obvious ultrastructural changes. The mRNA levels of the transcription factor nuclear factor-κB (NF-κB) and of pro-inflammatory cytokines, including inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), and prostaglandin E synthase (PTGEs), in chicken brain tissues (cerebrum, cerebellum, thalamus, brainstem and myelencephalon) on days 30, 60 and 90, respectively, were measured by real-time PCR. The protein expression of iNOS was detected by western blot. The results showed that after being treated with As₂O_3, the levels of inflammatory-related factor NF-κB and pro-inflammatory cytokines in chicken brain tissues increased (P < 0.05).

Conclusions

Arsenic exposure in the chickens triggered host defence and induced an inflammatory response by regulating the expression of inflammatory-related genes in the cerebrum, cerebellum, thalamus, brainstem and myelencephalon. These data form a foundation for further research on arsenic-induced neurotoxicity in Gallus gallus.

Electronic supplementary material

The online version of this article (doi:10.1186/s12917-017-1066-8) contains supplementary material, which is available to authorized users.

In vitro and in vivo anti-inflammatory properties of green synthesized silver nanoparticles using Viburnum opulus L. fruits extract

A green, rapid and cost effective method for the bio-synthesis of silver nanoparticles (AgNPs), using polyphenols present in European cranberry bush fruit extracts was developed. The obtained AgNPs were characterized by ultra-violet visible spectroscopy (UV-VIS), Fourier transform - infrared spectroscopy (FT-IR), transmission electron microscopy (TEM) and X-ray diffraction patterns (XRD). The average size of the spherical AgNPs was found to be 25nm. The anti-inflammatory effect of the biomaterials was investigated, both in vitro (on HaCaT cell line, exposed to UVB radiation) and in vivo (on acute inflammation model in Wistar rats). Our results support the conclusion that the photosynthesized silver nanoparticles present a potent anti-inflammatory activity and could be successfully used as therapeutic tools for treatment of inflammation.

Molecular signaling underlying bulleyaconitine A (BAA)-induced microglial expression of prodynorphin

Bulleyaconitine (BAA) has been shown to possess antinociceptive activities by stimulation of dynorphin A release from spinal microglia. This study investigated its underlying signal transduction mechanisms. The data showed that (1) BAA treatment induced phosphorylation of CREB (rather than NF-κB) and prodynorphin expression in cultured primary microglia, and antiallodynia in neuropathy, which were totally inhibited by the CREB inhibitor KG-501; (2) BAA upregulated phosphorylation of p38 (but not ERK or JNK), and the p38 inhibitor SB203580 (but not ERK or JNK inhibitor) and p38β gene silencer siRNA/p38β (but not siRNA/p38α) completely blocked BAA-induced p38 phosphorylation and/or prodynorphin expression, and antiallodynia; (3) BAA stimulated cAMP production and PKA phosphorylation, and the adenylate cyclase inhibitor DDA and PKA inhibitor H-89 entirely antagonized BAA-induced prodynorphin expression and antiallodynia; (4) The Gs-protein inhibitor NF449 completely inhibited BAA-increased cAMP level, prodynorphin expression and antiallodynia, whereas the antagonists of noradrenergic, corticotrophin-releasing factor, A1 adenosine, formyl peptide, D1/D2 dopamine, and glucagon like-peptide-1 receptors failed to block BAA-induced antiallodynia. The data indicate that BAA-induced microglial expression of prodynorphin is mediated by activation of the cAMP-PKA-p38β-CREB signaling pathway, suggesting that its possible target is a Gs-protein-coupled receptor - "aconitine receptor", although the chemical identity is not illustrated.

The α-cyclodextrin complex of the Moringa isothiocyanate suppresses lipopolysaccharide-induced inflammation in RAW 264.7 macrophage cells through Akt and p38 inhibition

In the last decades, a growing need to discover new compounds for the prevention and treatment of inflammatory diseases has led researchers to consider drugs derived from natural products as a valid option in the treatment of inflammation-associated disorders. The purpose of the present study was to investigate the anti-inflammatory effects of a new formulation of Moringa oleifera-derived 4-(α-L-rhamnopyranosyloxy)benzyl isothiocyanate as a complex with alpha-cyclodextrin (moringin + α-CD) on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells, a common model used for inflammation studies. In buffered/aqueous solution, the moringin + α-CD complex has enhanced the water solubility and stability of this isothiocyanate by forming a stable inclusion system. Our results showed that moringin + α-CD inhibits the production of inflammatory mediators in LPS-stimulated macrophages by down-regulation of pro-inflammatory cytokines (TNF-α and IL-1β), by preventing IκB-α phosphorylation, translocation of the nuclear factor-κB (NF-κB), and also via the suppression of Akt and p38 phosphorylation. In addition, as a consequence of upstream inhibition of the inflammatory pathway following treatment with moringin + α-CD, the modulation of the oxidative stress (results focused on the expression of iNOS and nitrotyrosine) and apoptotic pathway (Bax and Bcl-2) was demonstrated. Therefore, moringin + α-CD appears to be a new relevant helpful tool to use in clinical practice for inflammation-associated disorders.

Cannabinoid CB2 receptors are involved in the protection of RAW264.7 macrophages against the oxidative stress: an in vitro study

Research in the last decades has widely investigated the anti-oxidant properties of natural products as a therapeutic approach for the prevention and the treatment of oxidative-stress related disorders. In this context, several studies were aimed to evaluate the therapeutic potential of phytocannabinoids, the bioactive compounds of Cannabis sativa. Here, we examined the anti-oxidant ability of Cannabigerol (CBG), a non-psychotropic cannabinoid, still little known, into counteracting the hydrogen peroxide (H₂O₂)-induced oxidative stress in murine RAW264.7 macrophages. In addition, we tested selective receptor antagonists for cannabinoid receptors and specifically CB1R (SR141716A) and CB2R (AM630) in order to investigate through which CBG may exert its action. Taken together, our in vitro results showed that CBG is able to counteract oxidative stress by activation of CB2 receptors. CB2 antagonist pre-treatment indeed blocked the protective effects of CBG in H₂O₂ stimulated macrophages, while CB1R was not involved. Specifically, CBG exhibited a potent action in inhibiting oxidative stress, by down-regulation of the main oxidative markers (iNOS, nitrotyrosine and PARP-1), by preventing IκB-α phosphorylation and translocation of the nuclear factor-κB (NF-κB) and also via the modulation of MAP kinases pathway. On the other hand, CBG was found to increase anti-oxidant defense of cells by modulating superoxide dismutase-1 (SOD-1) expression and thus inhibiting cell death (results focused on balance between Bax and Bcl-2). Based on its anti-oxidant activities, CBG may hold great promise as an anti-oxidant agent and therefore used in clinical practice as a new approach in oxidative-stress related disorders.

Silibinin ameliorates Aβ25-35-induced memory deficits in rats by modulating autophagy and attenuating neuroinflammation as well as oxidative stress

Alzheimer's disease (AD) is a progressive, neurodegenerative disease. Accumulating evidence suggests that inflammatory response, oxidative stress and autophagy are involved in amyloid β (Aβ)-induced memory deficits. Silibinin (silybin), a flavonoid derived from the herb milk thistle, is well known for its hepatoprotective activities. In this study, we investigated the neuroprotective effect of silibinin on Aβ_25-35-injected rats. Results demonstrated that silibinin significantly attenuated Aβ_25-35-induced memory deficits in Morris water maze and novel object-recognition tests. Silibinin exerted anxiolytic effect in Aβ_25-35-injected rats as determined in elevated plus maze test. Silibinin attenuated the inflammatory responses, increased glutathione (GSH) levels and decreased malondialdehyde (MDA) levels, and upregulated autophagy levels in the Aβ_25-35-injected rats. In conclusion, silibinin is a potential candidate for AD treatment because of its anti-inflammatory, antioxidant and autophagy regulating activities.

Anti-Inflammatory Potential of Ethyl Acetate Fraction of Moringa oleifera in Downregulating the NF-κB Signaling Pathway in Lipopolysaccharide-Stimulated Macrophages

In the present investigation, we prepared four different solvent fractions (chloroform, hexane, butanol, and ethyl acetate) of Moringa oleifera extract to evaluate its anti-inflammatory potential and cellular mechanism of action in lipopolysaccharide (LPS)-induced RAW264.7 cells. Cell cytotoxicity assay suggested that the solvent fractions were not cytotoxic to macrophages at concentrations up to 200 µg/mL. The ethyl acetate fraction suppressed LPS-induced production of nitric oxide and proinflammatory cytokines in macrophages in a concentration-dependent manner and was more effective than the other fractions. Immunoblot observations revealed that the ethyl acetate fraction effectively inhibited the expression of inflammatory mediators including cyclooxygenase-2, inducible nitric oxide synthase, and nuclear factor (NF)-κB p65 through suppression of the NF-κB signaling pathway. Furthermore, it upregulated the expression of the inhibitor of κB (IκBα) and blocked the nuclear translocation of NF-κB. These findings indicated that the ethyl acetate fraction of M. oleifera exhibited potent anti-inflammatory activity in LPS-stimulated macrophages via suppression of the NF-κB signaling pathway.

Combination strategy of PARP inhibitor with antioxidant prevent bioenergetic deficits and inflammatory changes in CCI-induced neuropathy

Neuropathic pain, a debilitating pain condition and the underlying pathogenic mechanisms are complex and interwoven amongst each other and still there is scant information available regarding therapies which promise to treat the condition. Evidence indicate that oxidative/nitrosative stress induced poly (ADP-ribose) polymerase (PARP) overactivation initiate neuroinflammation and bioenergetic crisis culminating into neurodegenerative changes following nerve injury. Hence, we investigated the therapeutic effect of combining an antioxidant, quercetin and a PARP inhibitor, 4-amino 1, 8-naphthalimide (4-ANI) on the hallmark deficits induced by chronic constriction injury (CCI) of sciatic nerve in rats. Quercetin (25 mg/kg, p.o.) and 4-ANI (3 mg/kg, p.o.) were administered either alone or in combination for 14 days to examine sciatic functional index, allodynia and hyperalgesia using walking track analysis, Von Frey, acetone spray and hot plate tests respectively. Malondialdehyde, nitrite and glutathione levels were estimated to detect oxidative/nitrosative stress; mitochondrial membrane potential and cytochrome c oxidase activity to assess mitochondrial function; NAD & ATP levels to examine the bioenergetic status and levels of inflammatory markers were evaluated in ipsilateral sciatic nerve. Quercetin and 4-ANI alone improved the pain behaviour and biochemical alterations but the combination therapy demonstrated an appreciable reversal of CCI-induced changes. Nitrotyrosine and Poly ADP-Ribose (PAR) immunopositivity was decreased and nuclear factor erythroid 2-related factor (Nrf-2) levels were increased significantly in micro-sections of the sciatic nerve and dorsal root ganglion (DRG) of treatment group. These results suggest that simultaneous inhibition of oxidative stress-PARP activation cascade may potentially be useful strategies for management of trauma induced neuropathic pain.

Anti‑inflammatory effects of Ciwujianoside C3, extracted from the leaves of Acanthopanax henryi (Oliv.) Harms, on LPS‑stimulated RAW 264.7 cells

The present study aimed to investigate the unknown mechanisms underlying the anti‑inflammatory activity of Ciwujianoside C3 (CJS C3), extracted from the leaves of Acanthopanax henryi Harms, on lipopolysaccharide (LPS)‑stimulated RAW 264.7 cells. Cells were treated with CJS C3 for 1 h prior to the addition of 200 ng/ml LPS. Cell viability was measured using the MTS assay. Nitric oxide levels were determined by Griess assay. Proinflammatory cytokine production was measured by enzyme‑linked immunosorbent assay. The expression levels of cyclooxygenase (COX)‑2, inducible nitric oxide synthase (iNOS), and mitogen‑activated protein kinases (MAPKs) were investigated by western blotting, reverse transcription (RT)‑polymerase chain reaction (PCR) and RT‑quantitative PCR. Nuclear factor (NF)‑κB/p65 localization, and interaction of the TLR4 receptor with LPS was examined by immunofluorescence assay. The results indicated that CJS C3 exhibited no cytotoxicity at the measured concentrations. Treatment with CJS C3 inhibited NO production, proinflammatory cytokine levels, including interleukin (IL)‑6, tumor necrosis factor (TNF)‑α, and prostaglandin E2 (PGE2), and protein and mRNA expression levels of iNOS and COX‑2. Furthermore, CJS C3 suppressed phosphorylation of extracellular signal‑regulated kinases and c‑jun N‑terminal kinases. It was also able to suppress activation of NF‑κB via inhibition of the TLR4 signaling pathway. These results suggested that CJS C3 exerts inhibitory effects on LPS‑induced PGE2, NO, IL‑6 and TNF‑α production. In addition, iNOS and COX‑2 expression was decreased in murine macrophages. These inhibitory effects may be achieved via suppression of MAPKs and NF‑κB phosphorylation following inhibition of the TLR4 signaling pathway.

Enhanced binding capability of nuclear factor-κB with demethylated P2X3 receptor gene contributes to cancer pain in rats

Supplemental Digital Content is Available in the Text.

Epigenetic regulations of P2X3 receptors play a crucial role in cancer pain. Targeting p65 binding to demethylated P2X3 receptor gene suppresses cancer pain.

Nuclear factor-kappa B (NF-κB) signaling is implicated in both cancer development and inflammation processes. However, the roles and mechanisms of NF-κB signaling in the development of cancer-induced pain (CIP) remain unknown. This study was designed to investigate the roles of the p65 subunit of NF-κB in regulation of the purinergic receptor (P2X3R) plasticity in dorsal root ganglion (DRG) of CIP rats. We showed here that tumor cell injection produced mechanical and thermal hyperalgesia, and an enhanced body weight–bearing difference, which was correlated with an upregulation of p65 and P2X3R expression in lumber DRGs and a potentiation of ATP-evoked responses of tibia-innervating DRG neurons. Inhibition of NF-κB signaling using p65 inhibitor pyrrolidine dithiocarbamate, BAY-11-7082, or lentiviral-p65 short-hairpin RNA significantly attenuated CIP and reversed the activities of P2X3R. Interestingly, tumor cell injection led to a significant demethylation of CpG island in p2x3r gene promoter and enhanced ability of p65 to bind the promoter of p2x3r gene. Our findings suggest that upregulation of P2X3R expression was mediated by the enhanced binding capability of p65 with demethylated promoter of p2x3r gene, thus contributing to CIP. NF-κBp65 might be a potential target for treating CIP, a neuropathic pain generated by tumor cell–induced injury to nerves that innervate the skin.

Effects of Guchang Capsule on Dextran Sulphate Sodium-Induced Experimental Ulcerative Colitis in Mice

Guchang capsule (GC) is a Chinese materia medica standardized product extracted from 15 Chinese traditional medical herbs and it has been clinically used in the treatment of intestinal disease. In this study, in order to extend the research of GC in intestinal disease, we were aiming to evaluate potential effects of GC on dextran sulphate sodium- (DSS-) induced murine experimental colitis and to elucidate the underlying mechanisms. GC treatment attenuated DSS-induced body weight loss and reduced the mortality. Moreover, GC treatment prevented DSS-induced colonic pathological damage; meanwhile it inhibited proinflammatory cytokines production in colon tissues. In vitro, GC significantly reduced LPS-induced proinflammatory cytokines production via inhibiting the activation of NF-κB in macrophage cells, and the expressions of several long noncoding RNAs (lncRNAs) which were reported in regulating NF-κB signaling pathway were obviously affected by adding GC into culture medium. In conclusion, our data suggested that administration of GC exhibits therapeutic effects on DSS-induced colitis partially through regulating the expression of NF-κB related lncRNAs in infiltrating immune cells.

Manipulating the NF-κB pathway in macrophages using mannosylated, siRNA-delivering nanoparticles can induce immunostimulatory and tumor cytotoxic functions

Tumor-associated macrophages (TAMs) are critically important in the context of solid tumor progression. Counterintuitively, these host immune cells can often support tumor cells along the path from primary tumor to metastatic colonization and growth. Thus, the ability to transform protumor TAMs into antitumor, immune-reactive macrophages would have significant therapeutic potential. However, in order to achieve these effects, two major hurdles would need to be overcome: development of a methodology to specifically target macrophages and increased knowledge of the optimal targets for cell-signaling modulation. This study addresses both of these obstacles and furthers the development of a therapeutic agent based on this strategy. Using ex vivo macrophages in culture, the efficacy of mannosylated nanoparticles to deliver small interfering RNA specifically to TAMs and modify signaling pathways is characterized. Then, selective small interfering RNA delivery is tested for the ability to inhibit gene targets within the canonical or alternative nuclear factor-kappaB pathways and result in antitumor phenotypes. Results confirm that the mannosylated nanoparticle approach can be used to modulate signaling within macrophages. We also identify appropriate gene targets in critical regulatory pathways. These findings represent an important advance toward the development of a novel cancer therapy that would minimize side effects because of the targeted nature of the intervention and that has rapid translational potential.

Lutein protects against ischemia/reperfusion injury in rat skeletal muscle by modulating oxidative stress and inflammation

BACKGROUND

Lutein is an antioxidant compound with potential biological effects. The present study investigated the protective role of Lutein against I/R injury in skeletal muscle.

METHODS

Animals were divided into three groups. Group I - sham operated; Group II- IR injury- Hind limb ischemia was induced by clamping the common femoral artery and vein. After 4 h of ischemia, the clamp was removed and the animals underwent 2 h of reperfusion. Group III-Lutein + IR injury- Rats with Lutein treatment received intraperitoneal injection 1 h before reperfusion. The skeletal tissues were analyzed for oxidative stress parameters (reactive oxygen species, protein carbonylation and sulfhydryls, lipid peroxidation). Antioxidant status was determined by evaluating Nrf-2 levels and antioxidant enzyme activities. The inflammatory mechanism was determined through NF-κB and COX-2 expressions. Pro-inflammatory cytokines were determined by ELISA.

RESULTS

The results showed that Lutein treatment significantly decreased the oxidative stress by reducing reactive oxygen species, protein carbonylation and sulphydryls, lipid peroxidation. Further, the levels of Nrf-2 and antioxidant status was significantly declined during IR injury compared to sham operated rats. Lutein treatment reduced the oxidative stress by enhancing Nrf-2 levels and antioxidant status. Skeletal IR injury enhanced the inflammatory signaling by up regulating NF-κB, COX-2 and various pro-inflammatory cytokines. NF-κB, COX-2 expressions were down regulated by Lutein treatment.

CONCLUSION

The study shows that Lutein protects against skeletal IR injury by down regulating oxidative stress and inflammatory mechanisms.

Selenium Deficiency Affects the mRNA Expression of Inflammatory Factors and Selenoprotein Genes in the Kidneys of Broiler Chicks

The aim of this study was to investigate the influence of Se deficiency on the transcription of inflammatory factors and selenoprotein genes in the kidneys of broiler chicks. One hundred fifty 1-day-old broiler chicks were randomly assigned to two groups fed with either a low-Se diet (L group, 0.033 mg/kg Se) or an adequate Se diet (C group, 0.2 mg/kg Se). The levels of uric acid (UA) and creatinine (Cr) in the serum and the mRNA levels of 6 inflammatory factors and 25 selenoprotein genes in the kidneys were measured as the clinical signs of Se deficiency occurred at 20 days old. The results indicated that the contents of UA and Cr in the serum increased in L group (p < 0.05), and the mRNA levels of the inflammatory factors (NF-κB, iNOS, COX-2, and TNF-α) increased in L group (p < 0.05). Meanwhile, the mRNA levels of PTGEs and HO-1 were not changed. In addition, 25 selenoprotein transcripts displayed ubiquitous expression in the kidneys of the chicks. The mRNA levels of 14 selenoprotein genes (Dio1, Dio2, GPx3, Sepp1, SelH, SelI, SelK, Sepn1, SelO, SelW, Sep15, SelT, SelU, and SelS) decreased, and 9 selenoprotein genes (GPx1, GPx2, GPx4, SelPb, Txnrd1, Txnrd2, Txnrd3, SPS2, and SelM) increased in L group (p < 0.05), but the Dio3 and Sepx1 mRNA levels did not change. The results indicated that Se deficiency resulted in kidney dysfunction, activation of the NF-κB pathway, and a change in selenoprotein gene expression. The changes of inflammatory factor and selenoprotein gene expression levels were directly related to the abnormal renal functions induced by Se deficiency.

Resveratrol ameliorates 2,4-dinitrofluorobenzene-induced atopic dermatitis-like lesions through effects on the epithelium

Background. Resveratrol is a natural polyphenol that exhibits anti-inflammatory effects. The aim of this study was to investigate the effects of resveratrol treatment on epithelium-derived cytokines and epithelial apoptosis in a murine model of atopic dermatitis-like lesions.

Material and Methods. Atopic dermatitis-like lesions were induced in BALB/c mice by repeated application of 2,4-dinitrofluorobenzene to shaved dorsal skin. Twenty-one BALB/c mice were divided into three groups: group I (control), group II (vehicle control), and group III (resveratrol). Systemic resveratrol (30 mg/kg/day) was administered repeatedly during the 6th week of the experiment. After the mice had been sacrificed, skin tissues were examined histologically for epithelial thickness. Epithelial apoptosis (caspase-3) and epithelium-derived cytokines [interleukin (IL)-25, IL-33, and thymic stromal lymphopoietin (TSLP)] were evaluated immunohistochemically.

Results. Epithelial thickness and the numbers of IL-25, IL-33, TSLP and caspase-3-positive cells were significantly higher in group II compared to group I mice. There was significant improvement in epithelial thickness in group III compared with group II mice (p < 0.05). The numbers of IL-25, IL-33, and TSLP-positive cells in the epithelium were lower in group III than in group II mice (p < 0.05). The number of caspase-3-positive cells, as an indicator of apoptosis, in the epithelium was significantly lower in group III than in group II mice (p < 0.05).

Conclusion. Treatment with resveratrol was effective at ameliorating histological changes and inflammation by acting on epithelium-derived cytokines and epithelial apoptosis.

Downstream activation of NF-κB in the EDA-A1/EDAR signalling in Sjögren's syndrome and its regulation by the ubiquitin-editing enzyme A20

Sjögren's syndrome (SS) is an autoimmune disease and the second most common chronic systemic rheumatic disorder. Prevalence of primary SS in the general population has been estimated to be approximately 1-3%, whereas secondary SS has been observed in 10-20% of patients with rheumatoid arthritis, systemic lupus erythematosus (SLE) and scleroderma. Despite this, its exact aetiology and pathogenesis are largely unexplored. Nuclear factor-kappa B (NF-κB) signalling mechanisms provide central controls in SS, but how these pathways intersect the pathological features of this disease is unclear. The ubiquitin-editing enzyme A20 (tumour necrosis factor-α-induced protein 3, TNFAIP3) serves as a critical inhibitor on NF-κB signalling. In humans, polymorphisms in the A20 gene or a deregulated expression of A20 are often associated with several inflammatory disorders, including SS. Because A20 controls the ectodysplasin-A1 (EDA-A1)/ectodysplasin receptor (EDAR) signalling negatively, and the deletion of A20 results in excessive EDA1-induced NF-κB signalling, this work investigates the expression levels of EDA-A1 and EDAR in SS human salivary glands epithelial cells (SGEC) and evaluates the hypothesis that SS SGEC-specific deregulation of A20 results in excessive EDA1-induced NF-κB signalling in SS. Our approach, which combines the use of siRNA-mediated gene silencing and quantitative pathway analysis, was used to elucidate the role of the A20 target gene in intracellular EDA-A1/EDAR/NF-κB pathway in SS SGEC, holding significant promise for compound selection in drug discovery.

Antibacterial and Anti-Inflammatory Activities of Physalis Alkekengi var. franchetii and Its Main Constituents

This study was designed to determine whether the 50% EtOH fraction from AB-8 macroporous resin fractionation of a 70% EtOH extract of P. Alkekengi (50-EFP) has antibacterial and/or anti-inflammatory activity both in vivo and in vitro and to investigate the mechanism of 50-EFP anti-inflammatory activity. Additionally, this study sought to define the chemical composition of 50-EFP. Results indicated that 50-EFP showed significant antibacterial activity in vitro and efficacy in vivo. Moreover, 50-EFP significantly reduced nitric oxide (NO), prostaglandin E₂ (PGE₂), tumor necrosis factor alpha (TNF-α), interleukin 1 (IL-1), and interleukin 6 (IL-6) production in lipopolysaccharide- (LPS-) stimulated THP-1 cells. Nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) (examined at the protein level) in THP-1 cells were suppressed by 50-EFP, which inhibited nuclear translocation of p65. Consistent with this anti-inflammatory activity in vitro, 50-EFP reduced inflammation in both animal models. Finally, seventeen compounds (8 physalins and 9 flavones) were isolated as major components of 50-EFP. Our data demonstrate that 50-EFP has antibacterial and anti-inflammatory activities both in vitro and in vivo. The anti-inflammatory effect appears to occur, at least in part, through the inhibition of nuclear translocation of p65. Moreover, physalins and flavones are probably the active components in 50-EFP that exert antibacterial and anti-inflammatory activities.

Total flavonoids of Hedyotis diffusa Willd inhibit inflammatory responses in LPS-activated macrophages via suppression of the NF-κB and MAPK signaling pathways

Nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways play a central role in inflammatory responses. Total flavonoids of Hedyotis diffusa Willd (TFHDW) are active compounds derived from Hedyotis diffusa Willd, which has been long used in Chinese traditional medicine for the treatment of various inflammatory diseases, including ulcerative colitis and bronchitis; however, the precise mechanisms underlying the effects of TFHDW are largely unknown. In the present study, the anti-inflammatory effect of TFHDW was evaluated and the underlying molecular mechanisms were investigated in an in vitro inflammatory model comprising lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. The results indicated that TFHDW inhibited the inflammatory response as it significantly reduced the LPS-induced expression of pro-inflammatory nitric oxide, tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1β in a concentration-dependent manner, without causing cytotoxicity. In addition, the mRNA expression of inducible nitric oxide synthase, TNF-α, IL-6 and IL-1β was suppressed by treatment with TFHDW in LPS-stimulated RAW 264.7 cells. Moreover, TFHDW treatment significantly inhibited the LPS-induced activation of NF-κB via the suppression of inhibitor of κB (IκB) phosphorylation, and reduced the phosphorylation of MAPK signaling molecules (p38, c-Jun N-terminal protein kinase and extracellular signal-regulated kinase 1/2), which resulted in the inhibition of cytokine expression. These findings suggest that TFHDW exerted anti-inflammatory activity via suppression of the NF-κB and MAPK signaling pathways.

Moringa oleifera Flower Extract Suppresses the Activation of Inflammatory Mediators in Lipopolysaccharide-Stimulated RAW 264.7 Macrophages via NF-κB Pathway

Aim of Study. Moringa oleifera Lam. (M. oleifera) possess highest concentration of antioxidant bioactive compounds and is anticipated to be used as an alternative medicine for inflammation. In the present study, we investigated the anti-inflammatory activity of 80% hydroethanolic extract of M. oleifera flower on proinflammatory mediators and cytokines produced in lipopolysaccharide- (LPS-) induced RAW 264.7 macrophages. Materials and Methods. Cell cytotoxicity was conducted by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Nitric oxide (NO) production was quantified through Griess reaction while proinflammatory cytokines and other key inflammatory markers were assessed through enzyme-linked immunosorbent assay (ELISA) and immunoblotting. Results. Hydroethanolic extract of M. oleifera flower significantly suppressed the secretion and expression of NO, prostaglandin E2 (PGE2), interleukin- (IL-) 6, IL-1β, tumor necrosis factor-alpha (TNF-α), nuclear factor-kappa B (NF-κB), inducible NO synthase (iNOS), and cyclooxygenase-2 (COX-2). However, it significantly increased the production of IL-10 and IκB-α (inhibitor of κB) in a concentration dependent manner (100 μg/mL and 200 μg/mL). Conclusion. These results suggest that 80% hydroethanolic extract of M. oleifera flower has anti-inflammatory action related to its inhibition of NO, PGE2, proinflammatory cytokines, and inflammatory mediator's production in LPS-stimulated macrophages through preventing degradation of IκB-α in NF-κB signaling pathway.

Inflammatory Factor Alterations in the Gastrointestinal Tract of Cocks Overexposed to Arsenic Trioxide

Exposure of people and animals to arsenic (As) is a global public health concern because As is widely distributed and associated with numerous adverse effects. As is a poisonous metalloid and arsenic trioxide (As2O3) is a form of As. Thus far, there have been very few reports on the inflammatory factor alterations of the gastrointestinal tract in birds exposed to As2O3. To investigate the possible correlation of As2O3 with inflammatory injury induced by an arsenic-supplemented diet in birds, 72 1-day-old male Hy-line cocks were selected and randomly divided into four groups. They were fed with either a commercial diet or an arsenic-supplemented diet containing 7.5, 15, and 30 mg/kg As2O3. The experiment lasted for 90 days, and samples of gizzard, glandular stomach, duodenum, jejunum, ileum, cecum, and rectum were collected at days 30, 60, and 90 of the experiment period. The inflammation-related genes were determined, including NF-κB, iNOS, COX-2, PTGEs, and TNF-α. The connection between arsenic dosage and inflammation-related genes was assessed. The content of inducible NO synthase (iNOS) was measured by Western blot of the samples. The results showed that arsenic supplementation increased the mRNA expression levels of inflammation-related genes in the gastrointestinal tract of cocks at different time points (p < 0.05). Moreover, the expression of the tissue and organ injury-related gene iNOS was upregulated (p < 0.05). These data suggest that As induces the inflammatory response and may trigger digestive function regression of the gastrointestinal tract by affecting inflammation-related genes and iNOS in cocks. This study offers some information on the mechanism of gastrointestinal tract inflammatory injury and iNOS expression level alterations induced by arseniasis.

MiR-31 modulates coelomocytes ROS production via targeting p105 in Vibrio splendidus challenged sea cucumber Apostichopus japonicus in vitro and in vivo

MiR-31 is a critical regulator of gene expression in many pathogenic processes in vertebrates. In this study, we identified p105 as a novel target of miR-31 in Apostichopus japonicus and investigated their regulatory roles in vitro and in vivo. The negative expression profiles between miR-31 and Ajp105 were detected in both LPS-exposed primary coelomocytes and Vibrio splendidus-challenged sea cucumber. Co-infection miR-31 mimics significantly depressed the expression of Ajp105 and increased ROS production in vitro. In contrast, miR-31 inhibitor significantly elevated the expression of Ajp105 and decreased ROS level. Consistently, miR-31 over-expression or Ajp105 silencing in vivo both greatly promoted ROS accumulation. Taken together, our findings confirmed that miR-31 could modulate respiratory burst via targeting Ajp105 during sea cucumber pathological development.

Inhibitory Effects of Epimedium Herb on the Inflammatory Response In Vitro and In Vivo

Epimedium Herb (EH) is a medicinal herb used in traditional Eastern Asia. In this study described, we investigated the biological effects of Epimedium Herb water extract (EHWE) on lipopolysaccharide (LPS)-mediated inflammation in macrophages and local inflammation in vivo. We also investigated the biological effects of EHWE on the production of inflammatory mediators, pro-inflammatory cytokines and related products, as well as nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) activation in LPS-stimulated macrophages. The analgesic effect of the acetic acid-induced writhing response and inhibitory activity on xylene-induced ear edema was also evaluated in mice. EHWE exhibited anti-inflammatory effects by inhibiting the production of nitric oxide (NO), interleukin (IL)-6 and IL-1β. In addition, EHWE strongly suppressed inducible nitric oxide synthase (iNOS), a NO synthesis enzyme, induced heme oxygenase-1 (HO-1) expression, and inhibited NF-κB activation as well as MAPK pathway phosphorylation. Furthermore, EHWE exhibited an analgesic effect on the writhing response and an inhibitory effect on ear edema in mice. For the first time, we demonstrated the anti-inflammatory effects and inhibitory mechanism in macrophages, as well as the inhibitory activity of EHWE in vivo. Our results indicate a potential use of EHWE as an inflammatory therapeutic agent developed from a natural substance.

Resveratrol attenuates HMGB1 signaling and inflammation in house dust mite-induced atopic dermatitis in mice

Resveratrol is a polyphenol abundantly found in red grape skin and is effective against antiaging and anti-inflammation associated with immune responses. In this study, we have investigated the effect of resveratrol on skin lesion, high mobility group box (HMGB)1 and inflammation pathway in an atopic dermatitis (AD) mouse model. AD-like lesion was induced by the application of house dust mite extract to the dorsal skin of NC/Nga mouse. After AD induction, resveratrol (20 mg/kg, p.o.) was administered daily for 2 weeks. We evaluated dermatitis severity, histopathological changes, serum levels of T helper (Th) cytokines (interferon (IFN)γ, interleukin (IL)-4) and changes in protein expression by Western blotting for HMGB1, receptor for advanced glycation end products (RAGE), toll like receptor (TLR)4, nuclear factor (NF)κB, phosphatidylinositide 3-kinase (PI3K), extracellular signal-regulated kinase (ERK)1/2, cyclooxygenase (COX)2, tumor necrosis factor (TNF)α, IL-1β, IL-2Rα and other inflammatory markers in the skin of AD mice. Treatment of resveratrol inhibited the development of the AD-like skin lesions. Histological analysis showed that resveratrol inhibited hypertrophy, intracellular edema, mast cells and infiltration of inflammatory cells. Furthermore, resveratrol treatment down-regulated HMGB1, RAGE, p-NFκB, p-PI3K, p-ERK1/2, COX2, TNFα, IL-1β, IL-2Rα, IFNγ and IL-4. Considering all these findings together, the HMGB1 pathway might be a potential therapeutic target in skin inflammation, and resveratrol treatment could have beneficial effects on AD by modulating the HMGB1 protein expression.

Neocryptotanshinone inhibits lipopolysaccharide-induced inflammation in RAW264.7 macrophages by suppression of NF-κB and iNOS signaling pathways

Neocryptotanshinone (NCTS) is a natural product isolated from traditional Chinese herb Salvia miltiorrhiza Bunge. In this study, we investigated its anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated mouse macrophage (RAW264.7) cells. MTT results showed that NCTS partly reversed LPS-induced cytotoxicity. Real-time PCR results showed that NCTS suppressed LPS-induced mRNA expression of inflammatory cytokines, including tumor necrosis factor α (TNFα), interleukin-6 (IL-6) and interleukin-1β (IL-1β). Moreover, NCTS could decrease LPS-induced nitric oxide (NO) production. Western blotting results showed that NCTS could down-regulate LPS-induced expression of inducible nitric oxide synthase (iNOS), p-IκBα, p-IKKβ and p-NF-κB p65 without affecting cyclooxygenase-2 (COX-2). In addition, NCTS inhibited LPS-induced p-NF-κB p65 nuclear translocation. In conclusion, these data demonstrated that NCTS showed anti-inflammatory effect by suppression of NF-κB and iNOS signaling pathways.

In vivo luminescent imaging of NF-κB activity and NF-κB-related serum cytokine levels predict pain sensitivities in a rodent model of peripheral neuropathy

BACKGROUND

Methods for the detection of the temporal and spatial generation of painful symptoms are needed to improve the diagnosis and treatment of painful neuropathies and to aid preclinical screening of molecular therapeutics.

METHODS

In this study, we utilized in vivo luminescent imaging of NF-κB activity and serum cytokine measures to investigate relationships between the NF-κB regulatory network and the presentation of painful symptoms in a model of neuropathy.

RESULTS

The chronic constriction injury model led to temporal increases in NF-κB activity that were strongly and non-linearly correlated with the presentation of pain sensitivities (i.e. mechanical allodynia and thermal hyperalgesia). The delivery of NEMO-binding domain peptide reduced pain sensitivities through the inhibition of NF-κB activity in a manner consistent with the demonstrated non-linear relationship. Importantly, the combination of non-invasive measures of NF-κB activity and NF-κB-regulated serum cytokines produced a highly predictive model of both mechanical (R(2) = 0.86) and thermal (R(2) = 0.76) pain centred on the NF-κB regulatory network (NF-κB, IL-6, CXCL1).

CONCLUSIONS

Using in vivo luminescent imaging of NF-κB activity and serum cytokine measures, this work establishes NF-κB and NF-κB-regulated cytokines as novel multivariate biomarkers of pain-related sensitivity in this model of neuropathy that may be useful for the rapid screening of novel molecular therapeutics.

Modulation of HMGB1 translocation and RAGE/NFκB cascade by quercetin treatment mitigates atopic dermatitis in NC/Nga transgenic mice

Quercetin, glycosylated form of flavonoid compound, has potent antioxidant and anti-inflammatory properties. In this study, we have investigated the effects of quercetin on skin lesion, high-mobility group box (HMGB)1 cascade signalling and inflammation in atopic dermatitis (AD) mouse model. AD-like lesion was induced by the application of house dust mite extract to the dorsal skin of NC/Nga transgenic mouse. After AD induction, quercetin (50 mg/kg, p.o) was administered daily for 2 weeks. We evaluated dermatitis severity, histopathological changes and changes in protein expression by Western blotting for HMGB1, receptor for advanced glycation end products (RAGE), toll-like receptor (TLR)4, nuclear factor (NF)κB, nuclear factor erythroid-2-related factor (Nrf)2, kelch-like ECH-associated protein (Keap)1, extracellular signal-regulated kinase (ERK)1/2, cyclooxygenase (COX)2, tumor necrosis factor (TNF)α, interleukin (IL)-1β, IL-2Rα and other inflammatory markers in the skin of AD mice. In addition, serum levels of T helper (Th) cytokines (interferon (IFN)γ, IL-4) were measured by enzyme-linked immunosorbent assay. Quercetin treatment attenuated the development of AD-like skin lesions. Histological analysis showed that quercetin inhibited hyperkeratosis, parakeratosis, acanthosis, mast cells and infiltration of inflammatory cells. Furthermore, quercetin treatment downregulated cytoplasmic HMGB1, RAGE, nuclear p-NFκB, p-ERK1/2, COX2, TNFα, IL-1β, IL-2Rα, IFNγ and IL-4 and upregulated nuclear Nrf2. Our data demonstrated that the HMGB1/RAGE/NFκB signalling might play an important role in skin inflammation, and quercetin treatment could be a promising agent for AD by modulating the HMGB1/RAGE/NFκB signalling and induction of Nrf2 protein.

Ox-LDL induces dysfunction of endothelial progenitor cells via activation of NF-κB

Dyslipidemia increases the risks for atherosclerosis in part by impairing endothelial integrity. Endothelial progenitor cells (EPCs) are thought to contribute to endothelial recovery after arterial injury. Oxidized low-density lipoprotein (ox-LDL) can induce EPC dysfunction, but the underlying mechanism is not well understood. Human EPCs were cultured in endothelial growth medium supplemented with VEGF (10 ng/mL) and bFGF (10 ng/mL). The cells were treated with ox-LDL (50 µg/mL). EPC proliferation was assayed by using CCK8 kits. Expression and translocation of nuclear factor-kabba B (NF-κB) were evaluated. The level of reactive oxygen species (ROS) in cells was measured using H2DCF-DA as a fluorescence probe. The activity of NADPH oxidase activity was determined by colorimetric assay. Ox-LDL significantly decreased the proliferation, migration, and adhesion capacity of EPCs, while significantly increased ROS production and NADPH oxidase expression. Ox-LDL induced NF-κB P65 mRNA expression and translocation in EPCs. Thus ox-LDL can induce EPC dysfunction at least by increasing expression and translocation of NF-κB P65 and NADPH oxidase activity, which represents a new mechanism of lipidemia-induced vascular injury.

Wogonoside protects against dextran sulfate sodium-induced experimental colitis in mice by inhibiting NF-κB and NLRP3 inflammasome activation

Previous studies have demonstrated that wogonoside, the glucuronide metabolite of wogonin, has anti-inflammatory, anti-angiogenic and anticancer effects. However, the anti-inflammatory mechanism of wogonoside has not been fully elucidated. Recently, NLRP3 inflammasome has been reported to be correlated with inflammatory bowel disease for its ability to induce IL-1β release. Nevertheless, there are few drug candidates targeting NLRP3 inflammasome for this disease. In this study, we investigated the anti-inflammatory effect of wogonoside in dextran sulfate sodium (DSS)-induced murine colitis and further revealed the underlying mechanisms by targeting NF-κB and NLRP3 inflammasome. Wogonoside treatment dose-dependently attenuated DSS-induced body weight loss and colon length shortening. Moreover, wogonoside prevented DSS-induced colonic pathological damage, remarkably inhibited inflammatory cells infiltration and significantly decreased myeloperoxidase (MPO) and inducible nitric oxide synthase (iNOS) activities. The production of pro-inflammatory mediators in serum and colon was also significantly reduced by wogonoside. The underlying mechanisms for the protective effect of wogonoside in DSS-induced colitis may be attributed to its inhibition on NF-κB and NLRP3 inflammasome activation in colons. Furthermore, wogonoside markedly decreased production of IL-1β, TNF-α and IL-6 and suppressed mRNA expression of pro-IL-1β and NLRP3 in phorbol myristate acetate (PMA)-differentiated monocytic THP-1 cells via inhibiting the activation of NF-κB and NLRP3 inflammasome. In conclusion, our study demonstrated that wogonoside may exert its anti-inflammatory effect via dual inhibition of NF-κB and NLRP3 inflammasome, suggesting that wogonoside might be a potential effective drug for inflammatory bowel diseases.

Anti-inflammatory effect of Lycii radicis in LPS-stimulated RAW 264.7 macrophages

The root bark of Lycium barbarum (Lycii radicis cortex, LRC) is used as a cooling agent for fever and night sweats in East Asian traditional medicine. The inhibitory effect of LRC water extract on inflammation is unknown. In this study, the anti-inflammatory effect of LRC was investigated in lipopolysaccharide (LPS)-stimulated mouse macrophage, RAW 264.7 cells. LRC extract significantly decreased the LPS-induced production of inflammatory mediators, nitric oxide (NO), prostaglandin (PG) E2 and pro-inflammatory cytokines, interleukin (IL)-1β and IL-6 in the cells. In addition, LRC extract inhibited the LPS-induced expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 mRNA and protein, and inflammatory cytokines mRNA in the cells. The action mechanism of LRC underlies the blocking of LPS-mediated p38 and Jun N-terminal kinase (JNK), mitogen-activated protein kinases (MAPKs), and the nuclear factor (NF)-κB signaling pathway. These results indicate that LRC extract inhibits the inflammatory response in activated macrophages by down-regulating the transcription levels of inflammatory mediators and blocking the MAPKs and NF-κB pathway.

The effect of 4α,5α-epoxy-10α,14-dihydro-inuviscolide, a novel immunosuppressant isolated from Carpesium abrotanoides, on the cytokine profile in vitro and in vivo

The plant Carpesium abrotanoides (CA) is used in Asian herbal medicines as an insecticide and to treat bruises. However, the effect of single compounds from CA blooms and the mechanism of its immunosuppressive effect remain poorly understood. The aim of this study was to investigate the mechanism of the immunosuppressive effect in the three kinds of immune cells, and the immunosuppressive effect of CA bloom extract (CAE) in acute inflammation models (LPS and ConA-induced inflammation). Interleukin-6, IL-4, IL-13, IFNγ, and IL-10-but not TNFα-were significantly reduced in a dose-dependent manner by 4α,5α-epoxy-10α,14-dihydro-inuviscolide (INV). Furthermore, INV inhibited NF-κB transcriptional activation and IL-10 promoter activity in the same manner as for Bay11. Meanwhile, treatment with dexamethasone reduced the levels of IFNγ, but not IL-10, and resulted in no change in NF-κB transcriptional activation or the IL-10 promoter. INV did not affect PMA-induced IκB kinase complex phosphorylation, IκB degradation, or MAPK and the nuclear translocation of p65, as with DEX. The in vivo, CAE has an immunosuppressive effect on the LPS-induced inflammation response model by inhibiting the plasma level of IFNγ and IL-6 levels. CAE treatment also tends to attenuate the plasma level of IFNγ, IL-4, and IL-6 in ConA-induced inflammation. These findings indicate that INV causes the reduction of the cytokine profile by blocking the NF-κB transcription factor activation and the molecular mechanism by which INV operates could provide new insights into the unique mechanisms responsible for NF-κB inhibition, in contrast to established immunosuppressants, as a therapeutic agent for immunopathological treatment.

Anti-inflammatory and analgesic effects of pyeongwisan on LPS-stimulated murine macrophages and mouse models of acetic acid-induced writhing response and xylene-induced ear edema

Pyeongwisan (PW) is an herbal medication used in traditional East Asian medicine to treat anorexia, abdominal distension, borborygmus and diarrhea caused by gastric catarrh, atony and dilatation. However, its effects on inflammation-related diseases are unknown. In this study, we investigated the biological effects of PW on lipopolysaccharide (LPS)-mediated inflammation in macrophages and on local inflammation in vivo. We investigated the biological effects of PW on the production of inflammatory mediators, pro-inflammatory cytokines and related products as well as the activation of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) in LPS-stimulated macrophages. Additionally, we evaluated the analgesic effect on the acetic acid-induced writhing response and the inhibitory activity on xylene-induced ear edema in mice. PW showed anti-inflammatory effects by inhibiting the production of nitric oxide (NO), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) and interleukin-1β (IL-1β). In addition, PW strongly suppressed inducible nitric oxide synthase (iNOS), a NO synthesis enzyme, induced heme oxygenase-1 (HO-1) expression and inhibited NF-κB activation and MAPK phosphorylation. Also, PW suppressed TNF-α, IL-6 and IL-1β cytokine production in LPS-stimulated peritoneal macrophage cells. Furthermore, PW showed an analgesic effect on the writhing response and an inhibitory effect on mice ear edema. We demonstrated the anti-inflammatory effects and inhibitory mechanism in macrophages as well as inhibitory activity of PW in vivo for the first time. Our results suggest the potential value of PW as an inflammatory therapeutic agent developed from a natural substance.

Anti-Inflammatory Effects of Water Chestnut Extract on Cytokine Responses via Nuclear Factor-κB-signaling Pathway

Water chestnut (Trapa japonica Flerov.) is an annual aquatic plant. In the present study, we showed that the treatment of water chestnut extracted with boiling water resulted in a significant increase 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity and decrease the intracellular H₂O₂-induced accumulation of reactive oxygen species. In addition, water chestnut extract (WCE) inhibited lipopolysaccharide (LPS)-induced nitric oxide production and suppressed mRNA and protein expression of the inducible nitric oxide synthase gene. The cytokine array results showed that WCE inhibited inflammatory cytokine secretion. Also, WCE reduced tumor necrosis factor-α-and interleukin-6-induced nuclear factor-αB activity. Furthermore, during sodium lauryl sulfate (SLS)-induced irritation of human skin, WCE reduced SLS-induced skin erythema and improved barrier regeneration. These results indicate that WCE may be a promising topical anti-inflammatory agent.