scholarly journals Inhibition of Notch signalling ameliorates experimental inflammatory arthritis

2013 ◽  
Vol 74 (1) ◽  
pp. 267-274 ◽  
Author(s):  
Jong-Sung Park ◽  
Seol-Hee Kim ◽  
Kwangmeyung Kim ◽  
Cheng-Hao Jin ◽  
Ki Young Choi ◽  
...  
Keyword(s):  
Proinflammatory Cytokines ◽  
Inflammatory Arthritis ◽  
Near Infrared ◽  
Joint Destruction ◽  
Disease Onset ◽  
Disease Process ◽  
Neutrophil Infiltration ◽  
Notch Signalling ◽  
Pharmacological Inhibition

ObjectiveTo test the hypothesis that Notch signalling plays a role in the pathogenesis of rheumatoid arthritis (RA) and to determine whether pharmacological inhibition of Notch signalling with γ-secretase inhibitors can ameliorate the RA disease process in an animal model.MethodsCollagen-induced arthritis was induced in C57BL/6 or Notch antisense transgenic mice by immunisation with chicken type II collagen (CII). C57BL/6 mice were administered with different doses of inhibitors of γ-secretase, an enzyme required for Notch activation, at disease onset or after onset of symptoms. Severity of arthritis was monitored by clinical and histological scores, and in vivo non-invasive near-infrared fluorescence (NIRF) images. Micro-CT was used to confirm joint destruction. The levels of CII antibodies and cytokines in serum were determined by ELISA and bead-based cytokine assay. The expression levels of cytokines were studied by quantitative PCR in rheumatoid synovial fibroblasts.ResultsThe data show that Notch signalling stimulates synoviocytes and accelerates their production of proinflammatory cytokines and immune responses involving the upregulation of IgG1 and IgG2a. Pharmacological inhibition of γ-secretase and antisense-mediated knockdown of Notch attenuates the severity of inflammatory arthritis, including arthritis indices, paw thickness, tissue damage and neutrophil infiltration, and reduces the levels of active NF-κB, ICAM-1, proinflammatory cytokines and matrix metalloproteinase-3 activity in the mouse model of RA.ConclusionsThese results suggest that Notch is involved in the pathogenesis of RA and that inhibition of Notch signalling is a novel approach for treating RA.

scholarly journals Campylobacter jejuni-Induced Cytokine Responses in Avian Cells

2005 ◽  
Vol 73 (4) ◽  
pp. 2094-2100 ◽  
Author(s):  
Chris K. Smith ◽  
Pete Kaiser ◽  
Lisa Rothwell ◽  
Tom Humphrey ◽  
Paul A. Barrow ◽  
...  
Keyword(s):  
Campylobacter Jejuni ◽  
Proinflammatory Cytokines ◽  
Disease Process ◽  
Avian Host ◽  
Macrophage Cell ◽  
Proinflammatory Response ◽  
Cytokines And Chemokines ◽  
Cytokine Responses ◽  
Chick Kidney

ABSTRACT Campylobacter jejuni is a major cause of human inflammatory enteritis. During the course of human disease numerous proinflammatory cytokines are produced. Little is known, however, about the cytokine responses produced during the interaction of this bacterium with the avian host. Campylobacter has been considered a commensal of the avian host. Any differences in innate responses to this pathogen between the human and avian hosts should lead to a greater understanding of the disease process in humans. We have demonstrated expression of proinflammatory cytokines and chemokines in response to Campylobacter infection in avian primary chick kidney cells and the avian macrophage cell line HD11. The data indicate that Campylobacter can stimulate the avian host in a proinflammatory manner. The data strongly suggest that the lack of pathology in vivo is not due to an inability of Campylobacter to stimulate a proinflammatory response from avian cells.

scholarly journals Driving β2- While Suppressing α-Adrenergic Receptor Activity Suppresses Joint Pathology in Inflammatory Arthritis

2021 ◽  
Vol 12 ◽  
Author(s):  
Denise L. Bellinger ◽  
Carlo Wood ◽  
Jon E. Wergedal ◽  
Dianne Lorton
Keyword(s):  
Disease Progression ◽  
Inflammatory Arthritis ◽  
Joint Destruction ◽  
Disease Onset ◽  
Lymphocytic Infiltration ◽  
Bone Area ◽  
Talocrural Joint ◽  
Osteoclast Number ◽  
Hind Limbs ◽  
Adrenergic Antagonist

ObjectiveHypersympathetic activity is prominent in rheumatoid arthritis, and major life stressors precede onset in ~80% of patients. These findings and others support a link between stress, the sympathetic nervous system and disease onset and progression. Here, we extend previous research by evaluating how selective peripherally acting α/β2-adrenergic drugs affect joint destruction in adjuvant-induced arthritis.MethodsComplete Freund’s adjuvant induced inflammatory arthritis in male Lewis rats. Controls received no treatment. Arthritic rats then received vehicle or twice-daily treatment with the α-adrenergic antagonist, phentolamine (0.5 mg/day) and the β2-adrenergic agonist, terbutaline (1200 µg/day, collectively named SH1293) from day (D) of disease onset (D12) through acute (D21) and severe disease (D28). Disease progression was assessed in the hind limbs using dorsoplantar widths, X-ray analysis, micro-computed tomography, and routine histology on D14, D21, and D28 post-immunization.ResultsOn D21, SH1293 significantly attenuated arthritis in the hind limbs, based on reduced lymphocytic infiltration, preservation of cartilage, and bone volume. Pannus formation and sympathetic nerve loss were not affected by SH1293. Bone area and osteoclast number revealed high- and low-treatment-responding groups. In high-responding rats, treatment with SH1293 significantly preserved bone area and decreased osteoclast number, data that correlated with drug-mediated joint preservation. SH1293 suppressed abnormal bone formation based on reduced production of osteophytes. On D28, the arthritic sparing effects of SH1293 on lymphocytic infiltration, cartilage and bone sparing were maintained at the expense of bone marrow adipocity. However, sympathetic nerves were retracted from the talocrural joint.Conclusion and SignificanceOur findings support a significant delay in early arthritis progression by treatment with SH1293. Targeting sympathetic neurotransmission may provide a strategy to slow disease progression.

scholarly journals Antidepressants on Multiple Sclerosis: A Review of In Vitro and In Vivo Models

2021 ◽  
Vol 12 ◽  
Author(s):  
Eleni Stamoula ◽  
Spyridon Siafis ◽  
Ioannis Dardalas ◽  
Alexandra Ainatzoglou ◽  
Alkis Matsas ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Proinflammatory Cytokines ◽  
Immune Cell ◽  
Disease Onset ◽  
Neuroprotective Activity ◽  
Clinical Effects ◽  
In Vivo Models ◽  
Antidepressant Use

BackgroundIncreased prevalence of depression has been observed among patients with multiple sclerosis (MS) and correlated with the elevated levels of proinflammatory cytokines and the overall deregulation of monoaminergic neurotransmitters that these patients exhibit. Antidepressants have proved effective not only in treating depression comorbid to MS, but also in alleviating numerous MS symptoms and even minimizing stress-related relapses. Therefore, these agents could prospectively prove beneficial as a complementary MS therapy.ObjectiveThis review aims at illustrating the underlying mechanisms involved in the beneficial clinical effects of antidepressants observed in MS patients.MethodsThrough a literature search we screened and comparatively assessed papers on the effects of antidepressant use both in vitro and in vivo MS models, taking into account a number of inclusion and exclusion criteria.ResultsIn vitro studies indicated that antidepressants promote neural and glial cell viability and differentiation, reduce proinflammatory cytokines and exert neuroprotective activity by eliminating axonal loss. In vivo studies confirmed that antidepressants delayed disease onset and alleviated symptoms in Experimental Autoimmune Encephalomyelitis (EAE), the most prevalent animal model of MS. Further, antidepressant agents suppressed inflammation and restrained demyelination by decreasing immune cell infiltration of the CNS.ConclusionAntidepressants were efficient in tackling numerous aspects of disease pathophysiology both in vitro and in vivo models. Given that several antidepressants have already proved effective in clinical trials on MS patients, the inclusion of such agents in the therapeutic arsenal of MS should be seriously considered, following an individualized approach to minimize the adverse events of antidepressants in MS patients.

scholarly journals Cigarette smoke inducesmiR-132in Th17 cells that enhance osteoclastogenesis in inflammatory arthritis

2020 ◽  
Vol 118 (1) ◽  
pp. e2017120118
Author(s):  
Paula B. Donate ◽  
Kalil Alves de Lima ◽  
Raphael S. Peres ◽  
Fausto Almeida ◽  
Sandra Y. Fukada ◽  
...  
Keyword(s):  
Cigarette Smoking ◽  
Inflammatory Arthritis ◽  
Th17 Cells ◽  
Inflammatory Diseases ◽  
Joint Destruction ◽  
Chronic Inflammatory Disease ◽  
Healthy Individuals ◽  
Aryl Hydrocarbon ◽  
The Impact

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by joint destruction and severe morbidity. Cigarette smoking (CS) can exacerbate the incidence and severity of RA. Although Th17 cells and the Aryl hydrocarbon receptor (AhR) have been implicated, the mechanism by which CS induces RA development remains unclear. Here, using transcriptomic analysis, we show thatmicroRNA-132is specifically induced in Th17 cells in the presence of either AhR agonist or CS-enriched medium.miRNA-132thus induced is packaged into extracellular vesicles produced by Th17 and acts as a proinflammatory mediator increasing osteoclastogenesis through the down-regulation of COX2. In vivo, articular knockdown ofmiR-132in murine arthritis models reduces the number of osteoclasts in the joints. Clinically, RA patients express higher levels ofmiR-132than do healthy individuals. This increase is further elevated by cigarette smoking. Together, these results reveal a hitherto unrecognized mechanism by which CS could exacerbate RA and further advance understanding of the impact of environmental factors on the pathogenesis of chronic inflammatory diseases.

Fluorescent proteins for in vivo imaging, where's the biliverdin?

2020 ◽  
Vol 48 (6) ◽  
pp. 2657-2667
Author(s):  
Felipe Montecinos-Franjola ◽  
John Y. Lin ◽  
Erik A. Rodriguez
Keyword(s):  
Hydrogen Peroxide ◽  
In Vivo Imaging ◽  
Near Infrared ◽  
Fluorescent Protein ◽  
Fluorescent Proteins ◽  
Fluorescent Imaging ◽  
Infrared Light ◽  
Red Fluorescent Protein ◽  
Color Palette

Noninvasive fluorescent imaging requires far-red and near-infrared fluorescent proteins for deeper imaging. Near-infrared light penetrates biological tissue with blood vessels due to low absorbance, scattering, and reflection of light and has a greater signal-to-noise due to less autofluorescence. Far-red and near-infrared fluorescent proteins absorb light >600 nm to expand the color palette for imaging multiple biosensors and noninvasive in vivo imaging. The ideal fluorescent proteins are bright, photobleach minimally, express well in the desired cells, do not oligomerize, and generate or incorporate exogenous fluorophores efficiently. Coral-derived red fluorescent proteins require oxygen for fluorophore formation and release two hydrogen peroxide molecules. New fluorescent proteins based on phytochrome and phycobiliproteins use biliverdin IXα as fluorophores, do not require oxygen for maturation to image anaerobic organisms and tumor core, and do not generate hydrogen peroxide. The small Ultra-Red Fluorescent Protein (smURFP) was evolved from a cyanobacterial phycobiliprotein to covalently attach biliverdin as an exogenous fluorophore. The small Ultra-Red Fluorescent Protein is biophysically as bright as the enhanced green fluorescent protein, is exceptionally photostable, used for biosensor development, and visible in living mice. Novel applications of smURFP include in vitro protein diagnostics with attomolar (10−18 M) sensitivity, encapsulation in viral particles, and fluorescent protein nanoparticles. However, the availability of biliverdin limits the fluorescence of biliverdin-attaching fluorescent proteins; hence, extra biliverdin is needed to enhance brightness. New methods for improved biliverdin bioavailability are necessary to develop improved bright far-red and near-infrared fluorescent proteins for noninvasive imaging in vivo.

scholarly journals Real-time observation of tetrapyrrole binding to an engineered bacterial phytochrome

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Yusaku Hontani ◽  
Mikhail Baloban ◽  
Francisco Velazquez Escobar ◽  
Swetta A. Jansen ◽  
Daria M. Shcherbakova ◽  
...  
Keyword(s):  
Real Time ◽  
Rational Design ◽  
Near Infrared ◽  
Fluorescent Proteins ◽  
Covalent Bond ◽  
Binding Pocket ◽  
Tissue Imaging ◽  
Covalent Attachment ◽  
Time Resolved

AbstractNear-infrared fluorescent proteins (NIR FPs) engineered from bacterial phytochromes are widely used for structural and functional deep-tissue imaging in vivo. To fluoresce, NIR FPs covalently bind a chromophore, such as biliverdin IXa tetrapyrrole. The efficiency of biliverdin binding directly affects the fluorescence properties, rendering understanding of its molecular mechanism of major importance. miRFP proteins constitute a family of bright monomeric NIR FPs that comprise a Per-ARNT-Sim (PAS) and cGMP-specific phosphodiesterases - Adenylyl cyclases - FhlA (GAF) domain. Here, we structurally analyze biliverdin binding to miRFPs in real time using time-resolved stimulated Raman spectroscopy and quantum mechanics/molecular mechanics (QM/MM) calculations. Biliverdin undergoes isomerization, localization to its binding pocket, and pyrrolenine nitrogen protonation in <1 min, followed by hydrogen bond rearrangement in ~2 min. The covalent attachment to a cysteine in the GAF domain was detected in 4.3 min and 19 min in miRFP670 and its C20A mutant, respectively. In miRFP670, a second C–S covalent bond formation to a cysteine in the PAS domain occurred in 14 min, providing a rigid tetrapyrrole structure with high brightness. Our findings provide insights for the rational design of NIR FPs and a novel method to assess cofactor binding to light-sensitive proteins.

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