ic-87114 and Disease-Models--Animal

Cell-cell junctions are critical for the maintenance of cellular as well as tissue polarity and integrity. Dysfunction of airway epithelial barrier has been shown to be involved in the pathogenesis of acute lung injury (ALI). Yet the role of phosphatidylinositol 3-kinase delta (PI3Kδ) in dysregulation of airway epithelial barrier integrity in ALI has not been addressed. Mice were subjected to intratracheal instillation of lipopolysaccharide (LPS) to generate a ALI model. Two pharmacological inhibitors of PI3Kδ, IC87114 and AMG319, were respectively given to the mice. Expression of p110δ and its downstream substrate phospho-AKT (Ser473) was increased in LPS-exposed lungs. These increases were inhibited by IC87114 or AMG319. LPS led to pronounced lung injury that was accompanied by significant airway neutrophil recruitment and bronchial epithelial morphological alterations 72 h after exposure. We also found compromised expression of adherens junction protein E-cadherin and tight junction protein claudin-2 in the airway epithelial cells. Treatment with either IC87114 or AMG319 not only attenuated LPS-induced edema, lung injury and neutrophilc inflammation, reduced total protein concentration and IL-6, TNF-α secretion in BALF, but also restored epithelial E-cadherin and claudin-2 expression. In summary, our results showed that LPS can induce a delayed effect on airway epithelial barrier integrity that is mediated by PI3Kδ in a mouse model of ALI.

Topics: Acute Lung Injury; Adenine; Adenosine; Animals; Bronchoalveolar Lavage Fluid; Cadherins; Class I Phosphatidylinositol 3-Kinases; Claudins; Cytokines; Disease Models, Animal; Lipopolysaccharides; Lung; Male; Mice, Inbred BALB C; Quinazolines; Quinolines

When Zika virus emerged as a public health emergency there were no drugs or vaccines approved for its prevention or treatment. We used a high-throughput screen for Zika virus protease inhibitors to identify several inhibitors of Zika virus infection. We expressed the NS2B-NS3 Zika virus protease and conducted a biochemical screen for small-molecule inhibitors. A quantitative structure-activity relationship model was employed to virtually screen ∼138,000 compounds, which increased the identification of active compounds, while decreasing screening time and resources. Candidate inhibitors were validated in several viral infection assays. Small molecules with favorable clinical profiles, especially the five-lipoxygenase-activating protein inhibitor, MK-591, inhibited the Zika virus protease and infection in neural stem cells. Members of the tetracycline family of antibiotics were more potent inhibitors of Zika virus infection than the protease, suggesting they may have multiple mechanisms of action. The most potent tetracycline, methacycline, reduced the amount of Zika virus present in the brain and the severity of Zika virus-induced motor deficits in an immunocompetent mouse model. As Food and Drug Administration-approved drugs, the tetracyclines could be quickly translated to the clinic. The compounds identified through our screening paradigm have the potential to be used as prophylactics for patients traveling to endemic regions or for the treatment of the neurological complications of Zika virus infection.

Topics: Animals; Antiviral Agents; Artificial Intelligence; Chlorocebus aethiops; Disease Models, Animal; Drug Evaluation, Preclinical; High-Throughput Screening Assays; Immunocompetence; Inhibitory Concentration 50; Methacycline; Mice, Inbred C57BL; Protease Inhibitors; Quantitative Structure-Activity Relationship; Small Molecule Libraries; Vero Cells; Zika Virus; Zika Virus Infection

Hyperactivation of phosphoinositol 3-kinase (PI3K) has been suggested to be a potential mechanism for endoplasmic reticulum (ER) stress-enhanced airway hyperresponsiveness, and PI3K inhibitors have been examined as asthma therapeutics. However, the regulatory mechanism linking PI3K to ER stress and related pathological signals in asthma have not been defined. To elucidate these pathogenic pathways, we investigated the influence of a selective PI3Kδ inhibitor, IC87114, on airway inflammation in an ovalbumin/lipopolysaccharide (OVA/LPS)-induced asthma model. In OVA/LPS-induced asthmatic mice, the activity of PI3K, downstream phosphorylation of AKT and activation of nuclear factor-κB (NF-κB) were all significantly elevated; these effects were reversed by IC87114. IC87114 treatment also reduced the OVA/LPS-induced ER stress response by enhancing the intra-ER oxidative folding status through suppression of protein disulfide isomerase activity, ER-associated reactive oxygen species (ROS) accumulation and NOX4 activity. Furthermore, inositol-requiring enzyme-1α (IRE1α)-dependent degradation (RIDD) of IRE1α was reduced by IC87114, resulting in a decreased release of proinflammatory cytokines from bronchial epithelial cells. These results suggest that PI3Kδ may induce severe airway inflammation and hyperresponsiveness by activating NF-κB signaling through ER-associated ROS and RIDD-RIG-I activation. The PI3Kδ inhibitor IC87114 is a potential therapeutic agent against neutrophil-dominant asthma.

Topics: Adenine; Animals; Asthma; Disease Models, Animal; Endoplasmic Reticulum Stress; Lipid Peroxidation; Lipopolysaccharides; Membrane Proteins; Mice; Nerve Tissue Proteins; NF-kappa B; Ovalbumin; Oxidation-Reduction; Oxidative Stress; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Quinazolines; Reactive Oxygen Species; Receptors, Cell Surface; Signal Transduction

An aneurysm is an inflammatory vascular condition. Phosphatidylinositol 3-kinases δ is highly expressed in leukocytes, and play a key role in innate immunity. However, the link between phosphatidylinositol 3-kinases δ and aneurysm development has not yet been elucidated.. Carotid ligation unexpectedly induced characteristic aneurysm formation beneath the ligation point in p110δ(D910A/D910A) mice (n=25; P<0.001 versus wild-type). Besides, p110δ inactivation exacerbated CaCl2-induced abdominal aortic aneurysms development. A reverse transcription polymerase chain reaction microarray revealed significant extracellular matrix components degradation and matrix metalloproteinases (MMPs) upregulation in the abdominal aorta of p110δ(D910A/D910A) mice. Similarly, the expression of both collagen I and IV was significantly decreased (n=10; P<0.05 versus wild-type) in carotid artery. Western blot assay confirmed that MMP-12 was significantly upregulated in arteries of p110δ(D910A/D910A) mice (n=10; P<0.01 versus wild-type). In vitro, p110δ inactivation marked increase peritoneal macrophages recruitment and synergistically enhance tumor necrosis factor-α-induced recruitment. A specific phosphatidylinositol 3-kinases δ inhibitor (IC87114) or genetic p110δ inactivation upregulated MMP-12 expression and c-Jun phosphorylation (n=6; P<0.05 versus wild-type macrophages). IC87114 also increased activator protein-1 DNA-binding activity (n=6; P<0.001 versus control) and enhanced the effect of tumor necrosis factor-α on activator protein-1-binding activity (n=5; P<0.01 versus tumor necrosis factor-α treatment groups). Knockdown of c-Jun suppressed the effect of the IC87114 and tumor necrosis factor-α on MMP-12 mRNA expression (n=5 in each group; P<0.01 versus scrRNA treatment groups).. Our findings demonstrate that p110δ inactivation leads to extracellular matrix degradation in vessels and promotes aneurysm development by inducing macrophages migration and upregulating the activator protein-1/MMP-12 pathway in macrophages.

Topics: Adenine; Animals; Aorta, Abdominal; Aortic Aneurysm, Abdominal; Calcium Chloride; Carotid Artery Injuries; Carotid Artery, Common; Cell Line; Class I Phosphatidylinositol 3-Kinases; Disease Models, Animal; Enzyme Activation; Extracellular Matrix Proteins; Gene Expression Regulation, Enzymologic; Ligation; Macrophages, Peritoneal; Male; Matrix Metalloproteinase 12; Mice, Inbred C57BL; Mice, Knockout; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Protein Kinase Inhibitors; Quinazolines; RNA Interference; Signal Transduction; Transcription Factor AP-1; Transfection; Tumor Necrosis Factor-alpha

Bronchial asthma is characterized by inflammation of the airways, which is usually accompanied by increased vascular permeability, resulting in plasma exudation. Vascular endothelial growth factor (VEGF) has been implicated in contributing to asthmatic tissue edema through its effect on vascular permeability. Many cellular responses of VEGF are regulated by the lipid products of phosphoinositide 3-kinase (PI3K). However, the effect of PI3K catalytic subunit p110delta on VEGF-mediated signaling is unknown. Recently, an isoform-specific small molecule inhibitor, IC87114, which is selective for p110delta catalytic activity, has been identified.. We have sought to investigate the role of PI3K-delta, more specifically in the increase of vascular permeability.. Female BALB/c mice were sensitized and challenged with ovalbumin. We have investigated the effect of IC87114 on airway inflammation, T(H)2 cytokines expression, airway hyperresponsiveness, plasma extravasation, hypoxia-inducible factor 1alpha expression, and VEGF expression in a murine model of asthma.. Our current study has revealed that IC87114 reduces antigen-induced airway infiltration of inflammatory cells, secretion of T(H)2 cytokines in lungs, airway hyperresponsiveness, and vascular permeability. Moreover, we have found that inhibition of p110delta reduces ovalbumin-induced upregulation of VEGF level.. These results suggest that PI3K-delta inhibitor attenuates antigen-induced airway inflammation and hyperresponsiveness by preventing vascular leakage in mice.. These findings provide a crucial molecular mechanism for the potential role of PI3K-delta in asthma and other airway inflammatory disorders.

Topics: Adenine; Animals; Asthma; Bronchial Hyperreactivity; Bronchoalveolar Lavage Fluid; Capillary Permeability; Cinnamates; Class I Phosphatidylinositol 3-Kinases; Cytokines; Disease Models, Animal; Enzyme Inhibitors; Female; Hypoxia-Inducible Factor 1, alpha Subunit; Indoles; Leukocyte Count; Lung; Mice; Mice, Inbred BALB C; Ovalbumin; Phosphoinositide-3 Kinase Inhibitors; Pneumonia; Quinazolines; Receptors, Vascular Endothelial Growth Factor; Vascular Endothelial Growth Factor A

Increased expression of phosphoinositide 3-kinase (PI3-kinase) mediates elevated tone in the aorta from hypertensive deoxycorticosterone acetate (DOCA)-salt rats. In this article, we hypothesized that (1) alterations observed with respect to PI3-kinase observed in the aorta would also occur in mesenteric resistance arteries responsible for determining total peripheral resistance (TPR) and (2) p110delta activity was increased and localized to vascular smooth muscle cells (VSMCs), and was responsible for the increase in spontaneous tone in aortae from DOCA-salt rats. Mesenteric resistance arteries and aorta were isolated from DOCA-salt (190+/-3 mm Hg) and sham (121+/-2 mm Hg) rats. Myograph experiments revealed LY294002 (20 micromol/L), a PI3-kinase inhibitor, significantly decreased tone in mesenteric resistance arteries from DOCA-salt rats as compared with sham (-49+/-12 mg versus -10+/-7 mg). Western analyses of resistance artery protein homogenate revealed p85alpha and p110delta subunit protein, with significantly elevated levels of p110delta protein in the DOCA-salt compared with sham rats (0.30+/-0.07 versus 0.16+/-0.04% smooth muscle alpha-actin arbitrary units). Immunohistochemistry revealed p110delta-specific staining in VSMCs, with more intense staining in aortae from DOCA-salt rats. Compared with aortae from sham, p110delta-associated PI3-kinase activity was increased in DOCA-salt (158% of sham) and likely responsible for spontaneous tone because the p110delta specific inhibitor IC87114 decreased spontaneous tone in a concentration-dependent manner. Collectively, these data further implicate the p110delta isoform of PI3-kinase in arterial hyperresponsiveness in hypertension at the level of both large and small arteries.

Topics: Adenine; Animals; Aorta; Chromones; Class I Phosphatidylinositol 3-Kinases; Desoxycorticosterone; Disease Models, Animal; Enzyme Induction; Enzyme Inhibitors; Hypertension; Male; Mesenteric Arteries; Morpholines; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Protein Isoforms; Protein Subunits; Quinazolines; Rats; Rats, Sprague-Dawley; Sodium Chloride; Vascular Resistance

Although members of the class I phosphoinositide 3-kinases (PI3Ks) have been implicated in neutrophil inflammatory responses, the contribution of the individual PI3K isoforms in neutrophil activation has not been tractable with the non-selective inhibitors, LY294002 and wortmannin. We have developed a novel series of PI3K inhibitors that is selective for PI3K delta, an isoform expressed predominantly in hematopoietic cells. In addition to being selective between members of class I PI3Ks, representatives of these inhibitors such as IC980033 and IC87114 did not inhibit any protein kinases tested. Utilizing these inhibitors we report here a novel role for PI3K delta in neutrophil activation. Inhibition of PI3K delta with IC980033 and IC87114 blocked both fMLP- and TNF1 alpha-induced neutrophil superoxide generation and elastase exocytosis. The PI3K delta inhibitor IC87114 also blocked TNF1 alpha-stimulated elastase exocytosis from neutrophils in a mouse model of inflammation. To our knowledge, this is the first in vivo efficacy demonstration of a PI3K delta inhibitor in an animal model. Inhibition of PI3K delta, however, had no effect on in vitro neutrophil bactericidal activity and Fc gamma R-stimulated superoxide generation. Thus, PI3K delta plays an essential role in certain signaling pathways of neutrophil activation and appears to be an attractive target for the development of an anti-inflammatory therapeutic.

Topics: Adenine; Androstadienes; Animals; Anti-Inflammatory Agents; Chromones; Class I Phosphatidylinositol 3-Kinases; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme Inhibitors; Exocytosis; Inflammation; Leukocyte Elastase; Mice; Mice, Inbred BALB C; Morpholines; Neutrophils; Phosphatidylinositol 3-Kinases; Protein Isoforms; Quinazolines; Signal Transduction; Superoxides; Time Factors; Wortmannin