Yoshikazu Kuboi

Chemokines as Novel Therapeutic Targets for Inflammatory Bowel Disease

The inflammatory bowel diseases (IBD) such as Crohns disease (CD) and ulcerative colitis (UC) are illness characterized by a chronic clinical course of relapse and remission associated with self‐destructive inflammation of the gastrointestinal tract. In both UC and CD, leukocyte infiltration into the intestine is fundamental event in disease development and progression where the chemokines and their receptors are orchestrating the tissue‐specific and the cell type–selective trafficking of leukocytes. In this review, we will discuss the homeostatic and inflammatory roles of the chemokines and their receptors with their potentials and promise as molecular targets for therapeutic interventions in human IBD, focusing on the recently identified role of the CX3CL1–CX3CR1 axis, as well as the CCL20–CCR6, CCL25–CCR9, and CXCL10–CXCR3 pathways.

Discovery of a potent, metabolically stabilized resorcylic lactone as an anti-inflammatory lead

With bioactivity-guided phenotype screenings, a potent anti-inflammatory compound f152A1 has been isolated, characterized and identified as the known natural product LL-Z1640-2. Metabolic instability precluded its use for the study on animal disease models. Via total synthesis, a potent, metabolically stabilized analog ER-803064 has been created; addition of the (S)-Me group at C4 onto f152A1 has resulted in a dramatic improvement on its metabolic stability, while preserving the anti-inflammatory activities.

E6201, a Novel Kinase Inhibitor of Mitogen-Activated Protein Kinase/Extracellular Signal-Regulated Kinase Kinase-1 and Mitogen-Activated Protein Kinase/Extracellular Signal-Regulated Kinase Kinase Kinase-1: In Vivo Effects on Cutaneous Inflammatory Responses by Topical Administration

E6201 [(3S,4R,5Z,8S,9S,11E)-14-(ethylamino)-8,9,16-trihydroxy-3,4-dimethyl-3,4,9,10-tetrahydro-1H-2-benzoxacyclotetradecine-1,7(8H)-dione)] is a novel anti-inflammatory agent that has potent inhibitory effects on the production of proinflammatory cytokines from leukocytes and antiproliferative activity on keratinocytes. To characterize the in vivo pharmacological activity of E6201, topically administered E6201 was evaluated in several different animal models of dermatitis. E6201 formulated as an ointment or cream showed dose-dependent inhibition of croton oil-induced acute edema formation and neutrophil infiltration into mouse skin. In addition, E6201 cream inhibited the 1-fluoro-2,4-dinitrobenzene-induced contact hypersensitivity reaction mediated by T cells in mice. In this model, E6201 cream also suppressed the migration of neutrophils and lymphocytes into the inflammatory site. Pretreatment with E6201 cream attenuated phorbol-12 myristate 13-acetate-induced ornithine decarboxylase activity, a marker of proliferation in epidermis. Furthermore, E6201 ointment showed inhibitory effects on both mezerein-induced and interleukin (IL)-23-induced epidermal hyperplasia. E6201 also suppressed T cell receptor-stimulated IL-17 production from human T cells. These results indicate that topically administered E6201 may be a useful agent for the prevention and treatment of cutaneous inflammatory and hyperproliferative diseases such as psoriasis.

Calreticulin and integrin alpha dissociation induces anti-inflammatory programming in animal models of inflammatory bowel disease

Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn’s disease, is a chronic intestinal inflammatory condition initiated by integrins-mediated leukocyte adhesion to the activated colonic microvascular endothelium. Calreticulin (CRT), a calcium-binding chaperone, is known as a partner in the activation of integrin α subunits (ITGAs). The relationship between their interaction and the pathogenesis of IBD is largely unknown. Here we show that a small molecule, orally active ER-464195-01, inhibits the CRT binding to ITGAs, which suppresses the adhesiveness of both T cells and neutrophils. Transcriptome analysis on colon samples from dextran sodium sulfate-induced colitis mice reveals that the increased expression of pro-inflammatory genes is downregulated by ER-464195-01. Its prophylactic and therapeutic administration to IBD mouse models ameliorates the severity of their diseases. We propose that leukocytes infiltration via the binding of CRT to ITGAs is necessary for the onset and development of the colitis and the inhibition of this interaction may be a novel therapeutic strategy for the treatment of IBD.Inflammatory bowel disease (IBD) is initiated by integrins-mediated leukocyte adhesion to the activated colonic microvascular endothelium. Here, the authors show that inhibition of the calreticulin binding to integrin α subunits ameliorates the severity of IBD in animal models.

Anti-Fractalkine Antibody Suppresses Joint Destruction by Inhibiting Migration of Osteoclast Precursors to the Synovium in Experimental Arthritis

To elucidate the role of the fractalkine (FKN)/CX3CR1 pathway in joint destruction in rheumatoid arthritis.

E6130, a Novel CX3C Chemokine Receptor 1 (CX3CR1) Modulator, Attenuates Mucosal Inflammation and Reduces CX3CR1+ Leukocyte Trafficking in Mice with Colitis

The chemokine fractalkine (CX3C chemokine ligand 1; CX3CL1) and its receptor CX3CR1 are involved in the pathogenesis of several diseases, including inflammatory bowel diseases such as Crohn’s disease and ulcerative colitis, rheumatoid arthritis, hepatitis, myositis, multiple sclerosis, renal ischemia, and atherosclerosis. There are no orally available agents that modulate the fractalkine/CX3CR1 axis. [(3S,4R)-1-[2-Chloro-6-(trifluoromethyl)benzyl]-3-{[1-(cyclohex-1-en-1-ylmethyl)piperidin-4-yl]carbamoyl}-4-methylpyrrolidin-3-yl]acetic acid (2S)-hydroxy(phenyl)acetate (E6130) is an orally available highly selective modulator of CX3CR1 that may be effective for treatment of inflammatory bowel disease. We found that E6130 inhibited the fractalkine-induced chemotaxis of human peripheral blood natural killer cells (IC50 4.9 nM), most likely via E6130-induced down-regulation of CX3CR1 on the cell surface. E6130 had agonistic activity via CX3CR1 with respect to guanosine 5′-3-O-(thio)triphosphate binding in CX3CR1-expressing Chinese hamster ovary K1 (CHO-K1) membrane and had no antagonistic activity. Orally administered E6130 ameliorated several inflammatory bowel disease–related parameters in a murine CD4+CD45RBhigh T-cell-transfer colitis model and a murine oxazolone-induced colitis model. In the CD4+CD45RBhigh T-cell transfer model, E6130 inhibited the migration of CX3CR1+ immune cells and decreased the number of these cells in the gut mucosal membrane. These results suggest that E6130 is a promising therapeutic agent for treatment of inflammatory bowel disease.

Sa1101 Advanced In Vivo Live Imaging of Vascular Network of Colon Submucosa in IBD Models Using Two-Photon Laser Microscopy

G A A b st ra ct s and assessed CTT after the swallowing 24, 48 and 72 hours in constipation patients as well as 12 and 48 hours in healthy controls. Pearson correlation coefficient was assessed the association between MRI gadolinium test and ROM to measure the accuracy of gadolinium. Result: CCT measured though gadolinium in constipation patients(55±3h) were longer (P<0.05) than healthy controls(29±2h). CCT measured by barium strips in constipation patients(57±2h) were also statistically significant longer (P<0.05) than healthy controls(32±3h). The Pearson correlation coefficients were r=0.80(P<0.05)of the constipation group and r=0.82(P<0.05)of the healthy group, respectively. Conclusion: The gadolinium with MRI test is a novel technique to assess CCT. It is an effective, safe, radiation-free, easily recognizable and convenient method compared with ROM(Pic.1 and 2). The new explored gadolinium with MRI test can be an optional replacement to the traditional method, ROM, to assess CCT.