jnj-7777120 and Arthritis--Rheumatoid

Histamine is an important endogenous signaling molecule that is involved in a number of physiological processes including allergic reactions, gastric acid secretion, neurotransmitter release, and inflammation. The biological effects of histamine are mediated by four histamine receptors with distinct functions and distribution profiles (H1-H4). The most recently discovered histamine receptor (H4) has emerged as a promising drug target for treating inflammatory diseases. A detailed understanding of the role of the H4 receptor in human disease remains elusive, in part because low sequence similarity between the human and rodent H4 receptors complicates the translation of preclinical pharmacology to humans. This review provides an overview of H4 drug discovery programs that have studied cross-species structure-activity relationships, with a focus on the functional profiling of the 2-aminopyrimidine chemotype that has advanced to the clinic for allergy, atopic dermatitis, asthma, and rheumatoid arthritis.

Topics: Aminopyridines; Animals; Arthritis, Rheumatoid; Asthma; Dermatitis, Atopic; Drug Partial Agonism; Histamine Agonists; Histamine Antagonists; Humans; Hypersensitivity; Receptors, G-Protein-Coupled; Receptors, Histamine; Receptors, Histamine H4; Structure-Activity Relationship

Rheumatoid arthritis (RA) is one of the major autoimmune diseases with a global prevalence. Despite significant research into this disease, no drugs with acceptable safety profiles are yet available for its treatment. We investigated the possible anti-arthritic effects of the 4-methylhistamine (4-MeH) histamine 4 receptor (H4R) agonist and the JNJ77777120 (JNJ) H4R antagonist to explore the role of H4R in a mouse model of collagen antibody-induced arthritis (CAIA). Arthritis was induced via intravenous (tail vein) injection of Balb/c mice with a 5-clone cocktail of mAbs against collagen type II, followed by LPS, and the effects of treatment with 4-MeH or JNJ (30 mg kg(-1), i.p, twice daily) for 7 days (prophylactic or therapeutic regimens) were assessed. The results revealed increased paw edema, arthritic scores, joint histological inflammatory damage and matrix metalloproteinase-3 levels and high levels of Th1 pro-inflammatory cytokine mRNA and serum proteins in CAIA mice or following H4R activation via 4-MeH. Additionally, 4-MeH efficiently increased expression levels of NF-κB p65. JNJ-treated mice showed a substantial reduction in all the previously mentioned effects, with a similar trend being observed under prophylactic and therapeutic treatment regimens. The results of the present work indicate that JNJ exhibits significant anti-inflammatory and anti-arthritic activities, demonstrating the clear involvement of H4R antagonism in the pathogenesis and progression of RA.

Topics: Animals; Arthritis, Experimental; Arthritis, Rheumatoid; Cells, Cultured; Cytokines; Disease Progression; Female; Gene Expression Regulation; Humans; Immunophenotyping; Indoles; Injections, Intraperitoneal; Lymphocyte Activation; Matrix Metalloproteinase 3; Methylhistamines; Mice; Mice, Inbred BALB C; NF-kappa B; Piperazines; Receptors, G-Protein-Coupled; Receptors, Histamine; Receptors, Histamine H4; Th1 Cells