To investigate the role of the IL-6 classic- and trans-signaling pathways in corneal sterile inflammation and wound healing.
To assess the production of inflammatory molecules by corneal fibroblasts ...treated with supernatant derived from necrotic corneal epithelial cells, the authors used an antibody array. Expressions of membrane IL-6 receptor (mIL-6R) and soluble IL-6R (SIL-6R) by fibroblasts and epithelial cells were detected with flow cytometry and RT-PCR. Expressions of signal transducer and activator of transcription 3 (STAT3), vascular endothelial growth factor (VEGF), and monocyte chemotactic protein-1 (MCP-1) by fibroblasts stimulated with IL-6 alone or IL-6/SIL-6R were determined by ELISA. The effect of IL-6 or IL-6/SIL-6R on epithelial cell migration was investigated in vitro by the scratch assay, whereas expressions of IL-6R and S100 A4 in the corneas of mice were detected by immunohistochemistry after incision of the corneal stroma.
IL-1 derived from necrotic corneal epithelial cells induced the production of IL-6 by corneal fibroblasts. mIL-6R and SIL-6R mRNAs were expressed by both types of cells, although IL-6R protein at the cell surface was expressed only by epithelial cells. Expression of gp130 was detected in both types of cells. Activation of the IL-6 trans-signaling pathway induced the phosphorylation of STAT3, resulting in an increase of VEGF and MCP-1 production by corneal fibroblasts. Activation of the IL-6 classic-signaling pathway promoted the migration of corneal epithelial cells. IL-6R expression was also detected in activated fibroblasts and basal cells of the epithelium during the processes of wound healing in vivo.
The IL-6 classic- and trans-signaling pathways have an important role in corneal sterile inflammation and wound healing.
The effect of the solvent on the diastereoselectivity of the Joullié–Ugi three-component reaction (JU-3CR) using an α-substituted five-membered cyclic imine is revisited. The cis and trans isomers ...were generated in toluene and HFIP, respectively. Hammett analysis of the JU-3CR suggests the presence of two reaction mechanisms.
We recently reported that circular RNA is efficiently translated by a rolling circle amplification (RCA) mechanism in a cell-free Escherichia coli translation system. Recent studies have shown that ...circular RNAs composed of exonic sequences are abundant in human cells. However, whether these circular RNAs can be translated into proteins within cells remains unclear. In this study, we prepared circular RNAs with an infinite open reading frame and tested their translation in eukaryotic systems. Circular RNAs were translated into long proteins in rabbit reticulocyte lysate in the absence of any particular element for internal ribosome entry, a poly-A tail, or a cap structure. The translation systems in eukaryote can accept much simpler RNA as a template for protein synthesis by cyclisation. Here, we demonstrated that the circular RNA is efficiently translated in living human cells to produce abundant protein product by RCA mechanism. These findings suggest that translation of exonic circular RNAs present in human cells is more probable than previously thought.
Elevated skin surface pH has been reported in patients with atopic dermatitis. In this study, we explored the role of skin pH in the pathogenesis of atopic dermatitis using the NC/Tnd murine atopic ...dermatitis model. Alkalinization of the skin of asymptomatic NC/Tnd mice housed in specific pathogen-free conditions induced kallikrein 5 and activated protease-activated receptor 2, resulting in thymic stromal lymphopoietin secretion and a cutaneous T-helper 2 allergic response. This was associated with increased transepidermal water loss and development of eczematous lesions in these specific pathogen-free NC/Tnd mice, which normally do not suffer from atopic dermatitis. Injection of recombinant thymic stromal lymphopoietin also induced scratching behavior in the specific pathogen-free NC/Tnd mice. Thymic stromal lymphopoietin production and dermatitis induced by alkalinization of the skin could be blocked by the protease-activated receptor 2 antagonist ENMD-1068. In contrast, weak acidification of eczematous skin in conventionally housed NC/Tnd mice reduced kallikrein 5 activity and ameliorated the dermatitis. Onset of the dermatitis was associated with increased epidermal filaggrin expression and impaired activity of the sodium/hydrogen exchanger 1, a known regulator of skin pH. We conclude that alterations in skin pH directly modulate kallikrein 5 activity leading to skin barrier dysfunction, itch, and dermatitis via the protease-activated receptor 2–thymic stromal lymphopoietin pathway.
We assess if α retinal ganglion cells (αRGCs) and intrinsically photosensitive retinal ganglion cells (ipRGCs) survive in mouse models of glaucoma.
Two microliters of N-methyl-D-aspartate (NMDA; 1 ...mM) or PBS were injected intraocularly 7 days before sacrifice. Immunohistochemical analyses of the retina were performed using antibodies against RNA-binding protein with multiple splicing (RBPMS), osteopontin, and melanopsin. Immunohistochemical analyses also were performed in adult mice with glutamate/aspartate transporter (GLAST) deletion (GLAST knockout KO mice), a mouse model of normal tension glaucoma.
NMDA-induced loss of RBPMS-positive total RGCs was 58.4% ± 0.4% compared to PBS-treated controls, whereas the loss of osteopontin-positive αRGCs was 5.0% ± 0.6% and that of melanopsin-positive ipRGCs was 7.6% ± 1.6%. In GLAST KO mice, the loss of total RGCs was 48.4% ± 0.9% compared to wild-type mice, whereas the loss of αRGCs and ipRGCs was 3.9% ± 0.4% and 9.3% ± 0.5%, respectively. The distribution of survived total RGCs, αRGCs, and ipRGCs was similar regardless of the location of the retina.
These results suggest that αRGC and ipRGC are highly tolerant to NMDA-induced neurotoxicity and NTG-like neurodegeneration in GLAST KO mice.
Purpose
Vernal keratoconjunctivitis (VKC) is a severe and recurrent allergic conjunctivitis, the mechanism of which is not well understood. In this study, we investigated the role of oncostatin M ...(OSM) in the pathogenesis of VKC, with a focus on tissue remodeling.
Study design
Clinical and experimental.
Patients and methods
The OSM concentrations in tear fluid samples obtained from VKC patients and healthy controls were measured using ELISA, and the expression of OSM mRNA and protein in giant papillae resected from VKC patients was investigated using RT-PCR and immunohistochemistry, respectively. In cultured human conjunctival epithelial cells (HconEpiCs), expression of OSM receptor β (OSMRβ) was detected using immunocytochemical and FACS analyses. Finally, we investigated whether recombinant OSM activated STAT1 and STAT3 to induce the expression of various genes related to tissue remodeling in HconEpiCs, by using Western blot analysis, microarray analysis, and RT-PCR.
Results
The OSM concentration was higher in the tear fluid of VKC patients than in that of the healthy controls, and strong expression of OSM mRNA was found in the giant papillae. We also detected T cells expressing OSM in the giant papillae. In addition, HconEpiCs showed surface expression of OSMRβ. Recombinant human OSM strongly activated both STAT1 and STAT3 in HconEpiCs and induced various tissue remodeling-related genes, including MMP-1, MMP-3, IL-24, IL-20, serpinB3, S100A7, tenascin C, and SOCS3.
Conclusion
Our results suggest that OSM is one of the key molecules involved in remodeling of giant papillae in VKC.
Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used to reduce inflammation by suppressing cyclooxygenases (COXs). NSAID eye drops are frequently prescribed after ocular surgery to reduce ...inflammation and pain, but this treatment has clinically significant side effects, including corneal ulcer and perforation. The molecular mechanisms underlying these side effects remain unknown. Recently, the COX product 12(S)-hydroxyheptadeca-5Z,8E,10E-trienoic acid (12-HHT) was identified as an endogenous ligand for leukotriene B4 receptor 2 (BLT2), which is important in maintenance of epithelial homeostasis. We hypothesized that NSAID-dependent corneal damage is caused by reduced production of 12-HHT. Diclofenac eye drops decreased the abundance of downstream products of COX and delayed corneal wound healing in BALB/c mice. Expression of BLT2 was observed in murine ocular tissues including cornea, and in human corneal epithelial cell line and human primary corneal epithelial cells. In BLT2-knockout mice, corneal wound healing was delayed, but the diclofenac-dependent delay in corneal wound healing disappeared. 12-HHT accelerated wound closure both in BLT2-transfected corneal cell line and human primary corneal epithelial cells. Thus, our results reveal that NSAIDs delay corneal wound healing by inhibiting 12-HHT production, and suggest that stimulation of the 12-HHT/BLT2 axis represents a novel therapeutic approach to corneal wound healing.
Nucleoside analogues which show antimetabolic activity in cells have been successfully used in the treatment of various tumors. Nucleosides such as 1‐β‐D‐arabinofuranosylcytosine (araC), ...6‐mercaptopurine, fludarabine and cladribine play an important role in the treatment of leukemias, while gemcitabine, 5‐fluorouracil and its prodrugs are used extensively in the treatment of many types of solid tumors. All of these compounds are metabolized similarly to endogenous nucleosides and nucleotides. Active metabolites interfere with the de novo synthesis of nucleosides and nucleotides or inhibit the DNA chain elongation after being incorporated into the DNA strand as terminators. Furthermore, nucleoside antimetabolites incorporated into the DNA strand induce strand‐breaks and finally cause apoptosis. Nucleoside antimetabolites target one or more specific enzyme(s). The mode of inhibitory action on the target enzyme is not always similar even among nucleoside antimetabolites which have the same nucleoside base, such as araC and gemcitabine. Although both nucleosides are phosphorylated by deoxycytidine kinase and are also good substrates of cytidine deaminase, only gemcitabine shows antitumor activity against solid tumors. This suggests that differences in the pharmacological activity of these nucleoside antimetabolites may reflect different modes of action on target molecules. The design, in vitro cytotoxicity, in vivo antitumor activity, metabolism and mechanism of action of sugar‐modified cytosine nucleosides, such as (2′S)‐2′‐deoxy‐2′‐C‐methylcytidine (SMDC), 1‐(2‐deoxy‐2‐methylene‐β‐D‐erythro‐pentofuranosyl)cytosine (DMDC), 1‐(2‐C‐cyano‐2‐deoxy‐1‐β‐D‐arabino‐pentofuranosyl)cytosine (CNDAC) and 1‐(3‐C‐ethynyl‐β‐D‐ribo‐pentofuranosyl)cytosine (ECyd), developed by our groups, are discussed here.
How the innate and adaptive immune systems cooperate in the natural history of allergic diseases has been largely unknown. Plant-derived allergen, papain, and mite allergens, Der f 1 and Der p 1, ...belong to the same family of cysteine proteases. We examined the role of protease allergens in the induction of Ab production and airway inflammation after repeated intranasal administration without adjuvants and that in basophil/mast cell stimulation in vitro. Papain induced papain-specific IgE/IgG1 and lung eosinophilia. Der f 1 induced Der f 1-specific IgG1 and eosinophilia. Although papain-, Der f 1-, and Der p 1-stimulated basophils expressed allergy-inducing cytokines, including IL-4 in vitro, basophil-depleting Ab and mast cell deficiency did not suppress the papain-induced in vivo responses. Protease inhibitor-treated allergens and a catalytic site mutant did not induce the responses. These results indicate that protease activity is essential to Ab production and eosinophilia in vivo and basophil activation in vitro. IL-33-deficient mice lacked eosinophilia and had reduced papain-specific IgE/IgG1. Coadministration of OVA with papain induced OVA-specific IgE/IgG1, which was reduced in IL-33-deficient mice. We demonstrated IL-33 release, subsequent IL-33-dependent IL-5/IL-13 release, and activation of T1/ST2-expressing lineage(-)CD25(+)CD44(+) innate lymphoid cells in the lung after papain inhalation, suggesting the contribution of the IL-33-type 2 innate lymphoid cell-IL-5/IL-13 axis to the papain-induced airway eosinophilia. Rag2-deficient mice, which lack adaptive immune cells, showed significant, but less severe, eosinophilia. Collectively, these results suggest cooperation of adaptive immune cells and IL-33-responsive innate cells in protease-dependent allergic airway inflammation.
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