tranilast and Inflammation

Nucleic acid sensing pathways play an important role in the innate immune system, protecting hosts against infections. However, a large body of evidence supports a close association between aberrant activation of those pathways and autoimmune and inflammatory diseases. Part II of the digest series on small molecule approaches to autoimmune and inflammatory diseases concentrates on recent advances with respect to small molecule antagonists or inhibitors of the nucleic acid sensing pathways, including endosomal TLRs, NLRP3 inflammasome and cGAS-STING.

Topics: Animals; Autoimmune Diseases; DNA; Dose-Response Relationship, Drug; Humans; Inflammation; Molecular Structure; RNA; Small Molecule Libraries; Structure-Activity Relationship

Despite recent advances aimed to treat transmural inflammation in Crohn's disease (CD) patients, the progression to a structuring behavior still represents an issue for clinicians. As inflammation becomes chronic and severe, the attempt to repair damaged tissue can result in an excessive production of extracellular matrix components and deposition of connective tissue, thus favoring the formation of strictures. No specific and accurate clinical predictors or diagnostic tools for intestinal fibrosis exist, and to date, no genetic or serological marker is in routine clinical use. Therefore, intestinal fibrosis is usually diagnosed when it becomes clinically evident and strictures have already occurred. Anti-fibrotic agents such as tranilast, peroxisome proliferator-activated receptor gamma agonists, rho kinase inhibitors, and especially mesenchymal stem cell therapy have provided interesting results, but most of the evidence has been derived from studies performed in vitro. Therefore, current therapy of fibrotic strictures relies mainly on endoscopic and surgical procedures. Although its long-term outcomes may be debated, endoscopic balloon dilation appears to be the safest and most effective approach to treat appropriately selected strictures. The use of endoscopic stricturotomy is currently limited by the expertise needed to perform it and by the few data available in the literature. Some good results have been achieved by the positioning of self-expandable metal stents (SEMS). However, there is no concordance regarding the type of stent to use and for how long it should be left in place. The development of new specific SEMS may lead to better outcomes and to an increased use of this alternative in CD-related strictures.

Topics: Anti-Inflammatory Agents, Non-Steroidal; Constriction, Pathologic; Crohn Disease; Dilatation; Endoscopy, Gastrointestinal; Extracellular Matrix; Fibroblasts; Fibrosis; Gastrointestinal Agents; Humans; Inflammation; Intestines; ortho-Aminobenzoates; PPAR gamma; Protein Kinase Inhibitors; rho-Associated Kinases; Self Expandable Metallic Stents; Tumor Necrosis Factor Inhibitors

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease (ESRD). The development and progression of DN might involve multiple factors. Connective tissue growth factor (CCN2, originally known as CTGF) is the one which plays a pivotal role. Therefore, increasing attention is being paid to CCN2 as a potential therapeutic target for DN. Up to date, there are also many drugs or agents which have been shown for their protective effects against DN via different mechanisms. In this review, we only focus on the potential renoprotective therapeutic agents which can specifically abolish CCN2 expression or nonspecifically inhibit CCN2 expression for retarding the development and progression of DN.

Topics: Animals; Anthocyanins; Antibodies, Monoclonal; Connective Tissue Growth Factor; Diabetes Mellitus; Diabetic Nephropathies; Disease Progression; Exenatide; Guanidines; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Inflammation; Kidney; Kidney Failure, Chronic; Mice; Mycophenolic Acid; Oligonucleotides, Antisense; ortho-Aminobenzoates; Peptides; Renin-Angiotensin System; rho-Associated Kinases; Spironolactone; Venoms

Chronic graft-versus-host disease (cGVHD) is a marked complication of hematopoietic stem cell transplantation, and multiple organs can be affected by cGVHD-induced inflammation and fibrosis. In clinical settings, immunosuppressive agents have been the last resort to treat cGVHD. However, it has been only partially effective for cGVHD. Hence, efficacious treatment of cGVHD is eagerly awaited. Our previous work suggested that oxidative stress was elevated in cGVHD-disordered lacrimal glands and that epithelial-to-mesenchymal transition (EMT) was implicated in fibrosis caused by ocular cGVHD. In addition, our recent article demonstrated that thioredoxin interaction protein (TXNIP) and transcription factor nuclear factor kappa-light-chain-enhancer of activated B cells (NF-

Topics: Animals; Bone Marrow Transplantation; Carrier Proteins; Disease Models, Animal; Epithelial-Mesenchymal Transition; Fibrosis; Graft vs Host Disease; Hematopoietic Stem Cell Transplantation; Humans; Inflammation; Mice; NF-kappa B; ortho-Aminobenzoates; Thioredoxins

Tranilast (TL), an antiallergic agent, has been clinically used in the treatment of bronchial asthma, although its clinical use has been limited by its poor solubility in water, photodegradation and systemic side effects. In this study, we prepared a gel ointment containing TL nanoparticles (TLnano gel ointment), and investigated its usefulness. In addition, we demonstrated the preventive effects of the TLnano gel ointment on inflammation in adjuvant-induced arthritis (AA) rats. The TLnano gel ointment was prepared using Bead Smash 12 (a bead mill) and additives including sodium docusate, 2-hydroxypropyl-β-cyclodextrin, methylcellulose and Carbopol 934; the mean particle diameter of the TL nanoparticles was 71.0±25.4 nm. In in vitro skin penetration experiments, the amount of penetrated TL, the penetration rate (Jc) and the penetration coefficient through the skin (Kp) of the TLnano gel ointment were significantly higher than those of a gel ointment containing TL microparticles (TLmicro gel ointment; particle diameter 50.5±26.3 µm). The TL concentrations in the skin tissue and plasma of rats receiving the TLnano gel ointment were also higher than in rats receiving the TLmicro gel ointment. In addition, the application of the TLnano gel ointment attenuated the increase in paw edema of the hind feet of AA rats in comparison with AA rats treated with the TLmicro gel ointment. These results suggest that TL nanoparticles can be applied to the formulation of a transdermal system, and that a transdermal formulation using TL nanoparticles might be a delivery option for the clinical treatment of RA.

Topics: 2-Hydroxypropyl-beta-cyclodextrin; Acrylates; Administration, Cutaneous; Animals; Anti-Inflammatory Agents; Arthritis, Experimental; Arthritis, Rheumatoid; beta-Cyclodextrins; Edema; Gels; Inflammation; Male; Methylcellulose; Nanoparticles; Ointments; ortho-Aminobenzoates; Particle Size; Rats; Rats, Wistar; Skin; Skin Absorption; Solubility

The purpose of this study was to determine the effect of a synthetic tryptophan metabolite, tranilast [N-(3,4-dimethoxycinnamoyl)-anthranilic acid], on inflammatory and hemorrhagic areas after pulmonary radiofrequency ablation (RFA) in rabbits.. Percutaneous RFA using a 17-gauge LeVeen electrode was performed in normal rabbit lungs. The rabbits were divided into tranilast-treated (300 mg/kg/day, orally) and control groups (n = 24/group). The effects of tranilast were evaluated using multidetector-row computed tomography (CT), histology, and immunohistochemistry immediately after RFA on days 1, 7, 14, and 28.. Oral administration of tranilast significantly reduced the size of ablated lesions assessed using CT and histology on days 7 and 14. Furthermore, it reduced the hemorrhagic areas on day 7 and inflammatory areas on day 14, but did not affect the areas of coagulation necrosis on days 1, 7, 14, and 28. Immunohistochemical analysis showed an increase in the ratio of CD163-positive macrophage areas to rabbit macrophage (RAM11)-positive pan-macrophage areas and a decrease in the number of nuclear factor-κB-positive nuclei and CD31-positive microvessels in the tranilast group on days 7 and/or 14.. The results suggest that tranilast modulates the repair process after pulmonary RFA through macrophage accumulation, suppression of inflammation, and angiogenesis.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Catheter Ablation; Disease Models, Animal; Follow-Up Studies; Hemorrhage; Inflammation; Lung; ortho-Aminobenzoates; Rabbits; Treatment Outcome

Psoriasis is a common chronic skin disease characterized by recurrent erythromatous skin plaques that exhibit epidermal hyperplasia, variable inflammatory cell infiltrate, and abnormalities of the dermal vascularization. The involvement of angiogenic growth factors such as vascular endothelial growth factor (VEGF), matrix metalloproteinases (MMPs) and inflammatory cytokines such as IFNγ, IL-1, IL-2, TNFα, TGFα and β, IL-6, IL-8, amphiregulin and monocyte chemoattractant protein 1 (MCP-1) have been known to play pathogenic roles in traumatic psoriatic skin. However, anti-angiogenic and anti-inflammatory cytokines regimens might favorably affect the psoriasis disease process. Tranilast is an anti-allergic drug now emerging as anti-angiogenesis and anti-inflammatory effects. In vitro and in vivo experiments have also been strongly showed that tranilast would treat skin psoriasis by inhibition of involving factors. Herein, we hypothesize that local administration of tranilast may be potentially clinically useful in psoriasis.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Cytokines; Gene Expression Regulation; Gene Expression Regulation, Enzymologic; Humans; Inflammation; Matrix Metalloproteinases; Models, Theoretical; ortho-Aminobenzoates; Psoriasis; Skin; Vascular Endothelial Growth Factor A

This protocol describes microsphere-based protease assays for use in flow cytometry and high-throughput screening. This platform measures a loss of fluorescence from the surface of a microsphere due to the cleavage of an attached fluorescent protease substrate by a suitable protease enzyme. The assay format can be adapted to any site or protein-specific protease of interest and results can be measured in both real time and as endpoint fluorescence assays on a flow cytometer. Endpoint assays are easily adapted to microplate format for flow cytometry high-throughput analysis and inhibitor screening.

Topics: Animals; Biotinylation; Flow Cytometry; Fluorescence Resonance Energy Transfer; Green Fluorescent Proteins; High-Throughput Screening Assays; Humans; Inflammation; Kinetics; Microspheres; Peptide Hydrolases; Peptides; Reproducibility of Results; Temperature

Recent findings suggest the importance of mast cells in the pathogenesis of rheumatoid arthritis and their potential as a therapeutic target. Tranilast is an anti-allergic compound with a potent membrane-stabilizing effect on mast cells and a wide range of anti-inflammatory effects, thus may be advantageous in the treatment of arthritis. Here, we have evaluated the effects of tranilast on the progression of collagen-induced arthritis in mice.. Tranilast (400 mg.kg(-1).day(-1)) was orally administered for 8 weeks to mice with established collagen-induced arthritis. Arthritis was assessed by clinical signs and X-ray scores. In paw tissue, the numbers of mast cells and osteoclasts were measured by histological analysis, and several inflammatory factors were assessed by RT-PCR and Western blot analysis.*. TNF-alpha-positive mast cells were present extensively throughout the inflamed synovium of vehicle-treated arthritic mice, with some mast cells in close proximity to osteoclasts in areas of marked bone and cartilage destruction. Tranilast significantly reduced clinical and X-ray scores of arthritis and decreased numbers of TNF-alpha-positive mast cells and mRNA levels of TNF-alpha, chymase (mouse mast cell protease 4), tryptase (mouse mast cell protease 6), stem cell factor, interleukin-6, cathepsin-K, receptor activator of nuclear factor-kappaB, and of receptor activator of nuclear factor-kappaB-ligand, but increased interleukin-10 mRNA level in paws of arthritic mice. Osteoclast numbers were decreased by treatment with tranilast.. Tranilast possesses significant anti-rheumatic efficacy and, probably, this therapeutic effect is partly mediated by inhibition of mast cell activation and osteoclastogenesis.

Topics: Animals; Anti-Allergic Agents; Arthritis, Experimental; Arthritis, Rheumatoid; Bone and Bones; Carrier Proteins; Cartilage; Inflammation; Interleukin-10; Interleukin-6; Male; Mast Cells; Mice; Mice, Inbred DBA; Oligonucleotides; ortho-Aminobenzoates; Osteoclasts; RANK Ligand; Receptor Activator of Nuclear Factor-kappa B; Reverse Transcriptase Polymerase Chain Reaction; Stem Cell Factor; Synovial Membrane; Tumor Necrosis Factor-alpha; X-Rays

To test the hypothesis that stimulation of chymase secretion may contribute to plaque vulnerability and inhibition of chymase activity may enhance plaque stability.. Sixty eight-week-old male Syrian golden hamsters were randomly divided into normal control group, high-cholesterol (HC) treated group, HC+ovalbumin treated group and HC+tranilast treated group. The normal control group received a normal diet while the other three intervention groups received a high-cholesterol diet for 15 weeks. Hamsters in the HC+ovalbumin treated group underwent transcatheter pharmacological triggering at the end of week 15 after antigen sensitization and those in the HC+tranilast treated group were given tranilast intragastrically for 3 weeks before euthanasia. Serological, ultrasonographic, pathologic, immunohistochemical, and gene expression studies were performed in all animals. The total number of mast cells, proportion of degranulated mast cells and the number of extracellular granules in plaques, the apoptosis rate of vascular smooth cells, the local activities of chymase, the concentration of Ang II and the expression levels of inflammatory markers as well as plaque vulnerability index all increased significantly in HC+ovalbumin treated group, but remarkably decreased in HC+tranilast treated group, in comparison with the HC treated group. These results suggest that stimulation of chymase secretion contributes to plaque vulnerability while inhibition of chymase activity enhances plaque stability. We conclude that chymase activity provides a promising therapeutic target in the stabilization of atherosclerotic plaques.

Topics: Angiotensin II; Animals; Anti-Inflammatory Agents, Non-Steroidal; Aorta; Apoptosis; Atherosclerosis; Body Weight; Cell Degranulation; Cholesterol; Chymases; Cricetinae; Disease Models, Animal; Disease Progression; Immunohistochemistry; Inflammation; Inflammation Mediators; Lipids; Male; Mast Cells; Mesocricetus; Microscopy, Electron, Transmission; ortho-Aminobenzoates; Ovalbumin; Peptidyl-Dipeptidase A; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Rupture; Time Factors; Ultrasonography, Doppler, Duplex

Tranilast (N-[3',4'-dimethoxycinnamonyl] anthranilic acid), an orally active anti-allergic drug, is reported to exert the anti-inflammatory effects, but the underlying mechanisms that could explain the anti-inflammatory actions of tranilast remain largely unknown. Here, we found that tranilast induces heme oxygenase-1 (HO-1) expression through the extracellular signal-regulated kinase-1/2 (ERK1/2) pathway in RAW264.7 macrophages. Tranilast suppressed cyclooxygenase-2 (COX-2) and inducible nitric oxide (NO) synthase (iNOS) expression, and thereby reduced COX-2-derived prostaglandin E(2) (PGE(2)) and iNOS-derived NO production in lipopolysaccharide (LPS)-stimulated macrophages. Similarly, tranilast diminished tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) production. Interestingly, the effects of tranilast on LPS-induced PGE(2), NO, TNF-alpha, and IL-1beta production were partially reversed by the HO-1 inhibitor tin protoporphyrin, suggesting that tranilast-induced HO-1 expression is at least partly responsible for the resulting anti-inflammatory effects of the drug. Thus, HO-1 expression via ERK1/2 activation may be at least one of the possible mechanisms explaining the anti-inflammatory actions of tranilast.

Topics: Administration, Oral; Animals; Anti-Allergic Agents; Anti-Inflammatory Agents; Cell Line; Cyclooxygenase 2; Cytokines; Down-Regulation; Heme Oxygenase-1; Inflammation; Lipopolysaccharides; Macrophages; Mice; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Nitric Oxide Synthase Type II; ortho-Aminobenzoates; Up-Regulation

N(3,4-dimethoxycinnamoyl) anthranilic acid (tranilast) prevents the synchronous upregulation of isoforms and receptors of the transforming growth factor (TGF)-beta system after arterial injury and reduces restenosis after human coronary angioplasty. However, the effects of tranilast and the importance of the TGF-beta system in stent restenosis, in which inward remodeling is unimportant but inflammatory cell stimulation of neointima formation is exaggerated, are uncertain. Boston minipigs, treated with tranilast or vehicle, were subjected to endoluminal stenting, and the expression of TGF-beta1 and TGF-beta3, the expression of their signaling receptors ALK-5 and TbetaR-II, leukocyte numbers around the stent struts, and neointima development were assessed over 28 days. Stenting greatly increased early (5-day) mRNA expression of the 2 TGF-beta isoforms and their receptors. Immunohistochemical localization later showed that their concentrations were greatest in regions adjacent to stent struts, where leukocytes and collagen deposition were prevalent. Tranilast suppressed these elevations in TGF-beta mRNAs and reduced their immunoreactive peptides detectable around stent struts. The accumulation of leukocytes and deposition of collagen in these regions was also greatly inhibited by tranilast. These effects were associated with a 48% reduction in maximal neointimal cross-sectional area and 43% reduction in mean neointimal cross-sectional area at 28 days (P<0.05). We conclude that tranilast suppresses neointima development after stenting, effects that can be at least partly attributed to its ability to attenuate the induction of the TGF-beta system and leukocyte accumulation around stent struts.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Coronary Restenosis; Coronary Vessels; Drug Administration Schedule; Hyperplasia; Inflammation; Leukocytosis; Male; ortho-Aminobenzoates; Stents; Swine; Transforming Growth Factor beta; Tunica Intima; Up-Regulation

We evaluated the effect of orally administered tranilast, N-(3,4-dimethoxycinnamoyl) anthranilic acid, on histologic and histomorphometric changes after angioplasty or stent implantation in pig coronary arteries.. Tranilast, which has antikeloid and antiallergic properties and therefore may modulate the fibrotic and inflammatory tissue responses to angioplasty and stenting, has been shown to inhibit angiographic restenosis in small clinical trials. However, its effect on histomorphometric changes in coronary arteries after angioplasty and stenting is unknown.. Following initial pharmacokinetic studies in two pigs to determine desirable plasma levels of orally administered tranilast, 36 crossbred juvenile pigs were randomized to placebo or tranilast before undergoing balloon angioplasty in both the left anterior descending and left circumflex plus stent implantation in the right coronary artery. Oral tranilast was administered at 3 g/day starting 3 days before coronary injury and continued for 28 days until euthanasia. Injured vessels were harvested and sections analyzed by computer-assisted microscopic planimetry.. In balloon-injured vessels, tranilast was associated with a 37% reduction in neointimal area normalized to fracture length (0.47 +/- 0.01 vs. 0.74 +/- 0.03 mm; p < 0.001) and a 23% reduction in adventitial area normalized to vessel size (0.43 +/- 0.02 vs. 0.56 +/- 0.03; p = 0.003). In stented arteries, neointimal area normalized to injury score was 32% lower in the tranilast-treated group compared to control (1.94 +/- 0.17 vs. 2.86 +/- 0.29; p = 0.01).. In pig coronary arteries, tranilast was associated with a reduction in neointima formation and adventitial reaction after balloon injury. In stented vessels, tranilast was associated with a reduction in neointima formation normalized to injury score.

Topics: Administration, Oral; Angioplasty, Balloon, Coronary; Animals; Anti-Allergic Agents; Anti-Inflammatory Agents, Non-Steroidal; Coronary Disease; Coronary Vessels; Disease Models, Animal; Drug Evaluation, Preclinical; Female; Fibrosis; Inflammation; Male; ortho-Aminobenzoates; Random Allocation; Recurrence; Stents; Swine; Time Factors; Tunica Intima; Wound Healing; Wounds and Injuries

We examined the effects of tranilast, an anti-allergic agent, on hypersensitive inflammation and on morphology and functions of fibroblasts. In vivo, tranilast suppressed the content of collagen in granulation tissue of hypersensitive granulomatous inflammation induced by methylated bovine serum albumin (m-BSA) in rats. In culture, tranilast inhibited the TGF-beta-independent inflammatory exudate-induced stimulation of morphological changes of fibroblasts to myofibroblast-like cells and their proliferation. Collagen gel contraction by myofibroblast-like cells and fibroblasts was also inhibited by tranilast. Flow cytometric analysis revealed that tranilast suspended the cell cycle of fibroblasts at the G0/G1 phase. These results suggest that tranilast modulates the fibrosis and contraction of granulation tissue by inhibiting the growth of myofibroblast-like cells and fibroblasts.

Topics: Administration, Oral; Animals; Cell Division; Cells, Cultured; Collagen; Fibroblasts; Granuloma; Hypersensitivity; Inflammation; Male; ortho-Aminobenzoates; Rats; Rats, Sprague-Dawley; Specific Pathogen-Free Organisms

The effect of topically applied N-5', an inhibitor of chemical mediator release from mast cells, on the carrageenin-air-pouch inflammation was studied. The formation of granulation tissue, the accumulation of exudate and the number of infiltrating cells were significantly reduced by the treatment with N-5' (100 mg/kg). The collagen content in granulation tissue was dose-dependently reduced without affecting the noncollagen protein and DNA content by treatment with N-5'. At a dose of 100 mg/kg of N-5', prolyl hydroxylase activity in the tissue was significantly decreased. The selective inhibition of collagen accumulation in granulation tissue resulted from reduction of collagen biosynthesis in vivo. N-5' did not directly inhibit collagen synthesis by diploid fibroblasts, but inhibited fibroblast proliferation in culture. Such results indicate that one of the inhibitory mechanisms of collagen accumulation by N-5' in inflamed sites may involve the inhibition of fibroblast proliferation.

Topics: Animals; Carrageenan; Cell Division; Collagen; DNA; Fibroblasts; Granulation Tissue; Inflammation; Male; ortho-Aminobenzoates; Procollagen-Proline Dioxygenase; Rats; Time Factors