213 research outputs found
Identification of the Synthetic Cannabinoid R()WIN55,212-2 as a Novel Regulator of IFN Regulatory Factor 3 Activation and IFN- Expression
Beta Interferons (IFN-βs) represent one
of the first line treatments for relapsing remitting
multiple sclerosis (RRMS), slowing
disease progression whilst reducing the
frequency of relapses. Despite this, more
effective, well tolerated therapeutic strategies
are needed. Cannabinoids palliate experimental
autoimmune encephalomyelitis (EAE)
symptoms and have therapeutic potential in MS
patients although the precise molecular
mechanism for these effects is not understood.
Toll-like receptor (TLR) signaling controls
innate immune responses and TLRs are
implicated in MS. Here we demonstrate that the
synthetic cannabinoid R(+)WIN55,212-2 is a
novel regulator of TLR3 and TLR4 signaling by
inhibiting the pro-inflammatory signaling axis
triggered by TLR3 and TLR4 whilst selectively
augmenting TLR3-induced activation of IFN
regulatory factor 3 (IRF3) and expression of
IFN-β. We present evidence that
R(+)WIN55,212-2 strongly promotes the
nuclear localization of IRF3. The potentiation
of IFN-β expression by R(+)WIN55,212-2 is
critical for manifesting its protective effects in
the murine MS model EAE as evidenced by its
reduced therapeutic efficacy in the presence of
an anti-IFN-β antibody. R(+)WIN55,212-2 also
induces IFN-β expression in MS patient
peripheral blood mononuclear cells (PBMCs),
whilst downregulating inflammatory signaling
in these cells. These findings identify
R(+)WIN55,212-2 as a novel regulator of TLR3
signaling to IRF3 activation and IFN-β
expression and highlights a new mechanism
that may be open to exploitation in the
development of new therapeutics for the
treatment of MS
Identification of the Synthetic Cannabinoid R()WIN55,212-2 as a Novel Regulator of IFN Regulatory Factor 3 Activation and IFN- Expression
Beta Interferons (IFN-βs) represent one
of the first line treatments for relapsing remitting
multiple sclerosis (RRMS), slowing
disease progression whilst reducing the
frequency of relapses. Despite this, more
effective, well tolerated therapeutic strategies
are needed. Cannabinoids palliate experimental
autoimmune encephalomyelitis (EAE)
symptoms and have therapeutic potential in MS
patients although the precise molecular
mechanism for these effects is not understood.
Toll-like receptor (TLR) signaling controls
innate immune responses and TLRs are
implicated in MS. Here we demonstrate that the
synthetic cannabinoid R(+)WIN55,212-2 is a
novel regulator of TLR3 and TLR4 signaling by
inhibiting the pro-inflammatory signaling axis
triggered by TLR3 and TLR4 whilst selectively
augmenting TLR3-induced activation of IFN
regulatory factor 3 (IRF3) and expression of
IFN-β. We present evidence that
R(+)WIN55,212-2 strongly promotes the
nuclear localization of IRF3. The potentiation
of IFN-β expression by R(+)WIN55,212-2 is
critical for manifesting its protective effects in
the murine MS model EAE as evidenced by its
reduced therapeutic efficacy in the presence of
an anti-IFN-β antibody. R(+)WIN55,212-2 also
induces IFN-β expression in MS patient
peripheral blood mononuclear cells (PBMCs),
whilst downregulating inflammatory signaling
in these cells. These findings identify
R(+)WIN55,212-2 as a novel regulator of TLR3
signaling to IRF3 activation and IFN-β
expression and highlights a new mechanism
that may be open to exploitation in the
development of new therapeutics for the
treatment of MS
The Synthetic Cannabinoid R(+)WIN55,212-2 Augments Interferon-β Expression via Peroxisome Proliferator-activated Receptor-α
We have demonstrated that R()WIN55,212-2, a synthetic
cannabinoid that possesses cannabimimetic properties, acts as a
novel regulator of Toll-like receptor 3 (TLR3) signaling to interferon
(IFN) regulatory factor 3 (IRF3) activation and IFN-
expression, and this is critical for manifesting its protective
effects in a murine multiple sclerosis model. Here we investigated
the role of peroxisome proliferator-activated receptor-
(PPAR) in mediating the effects of R()WIN55,212-2 on this
pathway. Data herein demonstrate that the TLR3 agonist
poly(I:C) promotes IFN- expression and R()WIN55,212-2
enhances TLR3-induced IFN- expression in a stereoselective
manner via PPAR. R()WIN55,212-2 promotes increased
transactivation and expression of PPAR. Using the PPAR
antagonist GW6471, we demonstrate that R()WIN55,212-2
acts via PPAR to activate JNK, activator protein-1, and positive
regulatory domain IV to transcriptionally regulate the IFN-
promoter. Furthermore, GW6471 ameliorated the protective
effects of R()WIN55,212-2 during the initial phase of experimental
autoimmune encephalomyelitis. Overall, these findings
define PPAR as an important mediator in manifesting the
effects of R()WIN55,212-2 on the signaling cascade regulating
IFN- expression. The study adds to our molecular appreciation
of potential therapeutic effects of R()WIN55,212-2 in multiple
sclerosis
Differential protein profiling as a potential multi-marker approach for TSE diagnosis
Rona Barron - ORCID: 0000-0003-4512-9177 https://orcid.org/0000-0003-4512-9177This "proof of concept" study, examines the use of differential protein expression profiling using surface enhanced laser desorption and ionisationtime of flight mass spectrometry (SELDI-TOF) for the diagnosis of TSE disease. Spectral output from all proteins selectively captured from individual murine brain homogenate samples, are compared as "profiles" in groups of infected and non-infected animals. Differential protein expression between groups is thus highlighted and statistically significant protein "peaks" used to construct a panel of disease specific markers.
Studies at both terminal stages of disease and throughout the time course of disease have shown a disease specific protein profile or "disease fingerprint" which could be used to distinguish between groups of TSE infected and uninfected animals at an early time point of disease.
Results
Our results show many differentially expressed proteins in diseased and control animals, some at early stages of disease. Three proteins identified by SELDI-TOF analysis were verified by immunohistochemistry in brain tissue sections. We demonstrate that by combining the most statistically significant changes in expression, a panel of markers can be constructed that can distinguish between TSE diseased and normal animals.
Conclusion
Differential protein expression profiling has the potential to be used for the detection of disease in TSE infected animals. Having established that a "training set" of potential markers can be constructed, more work would be required to further test the specificity and sensitivity of the assay in a "testing set". Based on these promising results, further studies are being performed using blood samples from infected sheep to assess the potential use of SELDI-TOF as a pre-mortem blood based diagnostic.https://doi.org/10.1186/1471-2334-9-1889pubpub
Glucagon-like peptide-1 (GLP-1) and the regulation of human invariant natural killer T cells: lessons from obesity, diabetes and psoriasis
Aims/hypothesis The innate immune cells, invariant natural
killer T cells (iNKT cells), are implicated in the pathogenesis
of psoriasis, an inflammatory condition associated with
obesity and other metabolic diseases, such as diabetes and
dyslipidaemia. We observed an improvement in psoriasis severity in a patient within days of starting treatment with an
incretin-mimetic, glucagon-like peptide-1 (GLP-1) receptor
agonist. This was independent of change in glycaemic control.
We proposed that this unexpected clinical outcome resulted
from a direct effect of GLP-1 on iNKTcells.
Methods We measured circulating and psoriatic plaque
iNKT cell numbers in two patients with type 2 diabetes
and psoriasis before and after commencing GLP-1 analogue
therapy. In addition, we investigated the in vitro effects of
GLP-1 on iNKT cells and looked for a functional GLP-1
receptor on these cells.
Results The Psoriasis Area and Severity Index improved in
both patients following 6 weeks of GLP-1 analogue
therapy. This was associated with an alteration in iNKT
cell number, with an increased number in the circulation
and a decreased number in psoriatic plaques. The GLP-1
receptor was expressed on iNKT cells, and GLP-1 induced
a dose-dependent inhibition of iNKT cell cytokine secretion,
but not cytolytic degranulation in vitro.
Conclusions/interpretation The clinical effect observed and
the direct interaction between GLP-1 and the immune
system raise the possibility of therapeutic applications for
GLP-1 in inflammatory conditions such as psoriasis
The Arabidopsis protein phosphatase PP2C38 negatively regulates the central immune kinase BIK1
Plants recognize pathogen-associated molecular patterns (PAMPs) via cell surface-localized pattern recognition receptors (PRRs), leading to PRR-triggered immunity (PTI). The Arabidopsis cytoplasmic kinase BIK1 is a downstream substrate of several PRR complexes. How plant PTI is negatively regulated is not fully understood. Here, we identify the protein phosphatase PP2C38 as a negative regulator of BIK1 activity and BIK1-mediated immunity. PP2C38 dynamically associates with BIK1, as well as with the PRRs FLS2 and EFR, but not with the co-receptor BAK1. PP2C38 regulates PAMP-induced BIK1 phosphorylation and impairs the phosphorylation of the NADPH oxidase RBOHD by BIK1, leading to reduced oxidative burst and stomatal immunity. Upon PAMP perception, PP2C38 is phosphorylated on serine 77 and dissociates from the FLS2/EFR-BIK1 complexes, enabling full BIK1 activation. Together with our recent work on the control of BIK1 turnover, this study reveals another important regulatory mechanism of this central immune component
A RG-II type polysaccharide purified from Aconitum coreanum and their anti-inflammatory activity
Korean mondshood root polysaccharides (KMPS) isolated from the root of Aconitum coreanum (Lévl.) Rapaics have shown anti-inflammatory activity, which is strongly influenced by their chemical structures and chain conformations. However, the mechanisms of the anti-inflammatory effect by these polysaccharides have yet to be elucidated. A RG-II polysaccharide (KMPS-2E, Mw 84.8 kDa) was isolated from KMPS and its chemical structure was characterized by FT-IR and NMR spectroscopy, gas chromatography–mass spectrometry and high-performance liquid chromatography. The backbone of KMPS-2E consisted of units of [→6) -β-D-Galp (1→3)-β-L-Rhap-(1→4)-β-D-GalpA-(1→3)-β-D-Galp-(1→] with the side chain →5)-β-D-Arap (1→3, 5)-β-D-Arap (1→ attached to the backbone through O-4 of (1→3,4)-L-Rhap. T-β-D-Galp is attached to the backbone through O-6 of (1→3,6)-β-D-Galp residues and T-β-D-Ara is connected to the end group of each chain. The anti-inflammatory effects of KMPS-2E and the underlying mechanisms using lipopolysaccharide (LPS) - stimulated RAW 264.7 macrophages and carrageenan-induced hind paw edema were investigated. KMPS-2E (50, 100 and 200 µg/mL) inhibits iNOS, TLR4, phospho-NF-κB–p65 expression, phosphor-IKK, phosphor-IκB-α expression as well as the degradation of IκB-α and the gene expression of inflammatory cytokines (TNF-α, IL-1β, iNOS and IL-6) mediated by the NF-κB signal pathways in macrophages. KMPS-2E also inhibited LPS-induced activation of NF-κB as assayed by electrophorectic mobility shift assay (EMSA) in a dose-dependent manner and it reduced NF-κB DNA binding affinity by 62.1% at 200µg/mL. In rats, KMPS-2E (200 mg/kg) can significantly inhibit carrageenan-induced paw edema as ibuprofen (200 mg/kg) within 3 h after a single oral dose. The results indicate that KMPS-2E is a promising herb-derived drug against acute inflammation
Inhibition of NF-kB 1 (NF-kBp50) by RNA interference in chicken macrophage HD11 cell line challenged with Salmonellaenteritidis
The NF-kB pathway plays an important role in regulating the immunity response in animals. In this study, small interfering RNAs (siRNA) were used to specifically inhibit NF-kB 1 expression and to elucidate the role of NF-kB in the signal transduction pathway of the Salmonella challenge in the chicken HD11 cell line. The cells were transfected with either NF-kB 1 siRNA, glyceraldehyde 3-phosphate dehydrogenase siRNA (positive control) or the negative control siRNA for 24 h, followed by Salmonella enteritidis (SE) challenge or non-challenge for 1 h and 4 h. Eight candidate genes related to the signal pathway of SE challenge were selected to examine the effect of NF-kB 1 inhibition on their expressions by mRNA quantification. The results showed that, with a 36% inhibition of NF-kB 1 expression, gene expression of both Toll-like receptor (TLR) 4 and interleukin (IL)-6 was consistently and significantly increased at both 1 h and 4 h following SE challenge, whereas the gene expression of MyD88 and IL-1β was increased at 1 h and 4 h, respectively. These findings suggest a likely inhibitory regulation by NF-kB 1, and could lay the foundation for studying the gene network of the innate immune response of SE infection in chickens
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