hg-9-91-01 and Inflammation

Macrophage polarization into a phenotype producing high levels of anti-inflammatory IL-10 and low levels of proinflammatory IL-12 and TNF-α cytokines plays a pivotal role in the resolution of inflammation. Salt-inducible kinases synergize with TLR signaling to restrict the formation of these macrophages. The expression and function of salt-inducible kinase in primary human myeloid cells are poorly characterized. Here, we demonstrated that the differentiation from peripheral blood monocytes to macrophages or dendritic cells induced a marked up-regulation of salt-inducible kinase protein expression. With the use of 2 structurally unrelated, selective salt-inducible kinase inhibitors, HG-9-91-01 and ARN-3236, we showed that salt-inducible kinase inhibition significantly decreased proinflammatory cytokines (TNF-α, IL-6, IL-1β, and IL-12p40) and increased IL-10 secretion by human myeloid cells stimulated with TLR2 and-4 agonists. Differently than in mouse cells, salt-inducible kinase inhibition did not enhance IL-1Ra production in human macrophages. Salt-inducible kinase inhibition blocked several markers of proinflammatory (LPS + IFN-γ)-polarized macrophages [M(LPS + IFN-γ)] and induced a phenotype characterized by low TNF-α/IL-6/IL-12p70 and high IL-10. The downstream effects observed with salt-inducible kinase inhibitors on cytokine modulation correlated with direct salt-inducible kinase target (CREB-regulated transcription coactivator 3 and histone deacetylase 4) dephosphorylation in these cells. More importantly, we showed for the first time that salt-inducible kinase inhibition decreases proinflammatory cytokines in human myeloid cells upon IL-1R stimulation. Altogether, our results expand the potential therapeutic use of salt-inducible kinase inhibitors in immune-mediated inflammatory diseases.

Topics: AMP-Activated Protein Kinase Kinases; Cell Polarity; Gene Knockdown Techniques; Histone Deacetylases; Humans; Inflammation; Inflammation Mediators; Interferon-gamma; Interleukin-10; Interleukin-1beta; Lipopolysaccharides; Macrophages; Monocytes; Myeloid Cells; Phenotype; Phenylurea Compounds; Phosphorylation; Protein Serine-Threonine Kinases; Pyrimidines; Receptors, Interleukin-1; Repressor Proteins; RNA, Small Interfering; Signal Transduction; Toll-Like Receptor 2; Toll-Like Receptor 4; Transcription Factors; Tumor Necrosis Factor-alpha

Novel methods for the treatment of inflammatory and autoimmune diseases comprising the administration of salt-inducible kinase inhibitors are claimed. One novel inhibitor (HG-9-91-01) and the use of 2,4-diaminopyrimidine and 2,6-diaminopyrimidine derivatives are claimed. The use of such inhibitors upregulates the level of the anti-inflammatory cytokine IL-10 in macrophages.

Topics: Anti-Inflammatory Agents; Autoimmune Diseases; Drug Design; Enzyme Inhibitors; Humans; Inflammation; Interleukin-10; Macrophages; Patents as Topic; Phenylurea Compounds; Protein Serine-Threonine Kinases; Pyrimidines

Macrophages acquire strikingly different properties that enable them to play key roles during the initiation, propagation, and resolution of inflammation. Classically activated (M1) macrophages produce proinflammatory mediators to combat invading pathogens and respond to tissue damage in the host, whereas regulatory macrophages (M2b) produce high levels of anti-inflammatory molecules, such as IL-10, and low levels of proinflammatory cytokines, like IL-12, and are important for the resolution of inflammatory responses. A central problem in this area is to understand how the formation of regulatory macrophages can be promoted at sites of inflammation to prevent and/or alleviate chronic inflammatory and autoimmune diseases. Here, we demonstrate that the salt-inducible kinases (SIKs) restrict the formation of regulatory macrophages and that their inhibition induces striking increases in many of the characteristic markers of regulatory macrophages, greatly stimulating the production of IL-10 and other anti-inflammatory molecules. We show that SIK inhibitors elevate IL-10 production by inducing the dephosphorylation of cAMP response element-binding protein (CREB)-regulated transcriptional coactivator (CRTC) 3, its dissociation from 14-3-3 proteins and its translocation to the nucleus where it enhances a gene transcription program controlled by CREB. Importantly, the effects of SIK inhibitors on IL-10 production are lost in macrophages that express a drug-resistant mutant of SIK2. These findings identify SIKs as a key molecular switch whose inhibition reprograms macrophages to an anti-inflammatory phenotype. The remarkable effects of SIK inhibitors on macrophage function suggest that drugs that target these protein kinases may have therapeutic potential for the treatment of inflammatory and autoimmune diseases.

Topics: Analysis of Variance; Animals; Cell Line; Cyclobutanes; Cytokines; DNA Primers; DNA, Complementary; Fluorescent Antibody Technique; Immunoblotting; Indans; Inflammation; Interleukin-10; Macrophages; Magnetic Resonance Spectroscopy; Mice; Mice, Knockout; Molecular Structure; Morpholines; Phenylurea Compounds; Phosphorylation; Polymerase Chain Reaction; Protein Serine-Threonine Kinases; Proteomics; Pyrimidines; RNA Interference; Transcription Factors