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Akt is an important kinase in metabolism. Akt also phosphorylates and activates endothelial and neuronal nitric oxide (NO) synthases (eNOS and nNOS, respectively) expressed in M0 (unpolarized) macrophages. We showed that e/nNOS NO production downstream of bitter taste receptors enhances macrophage phagocytosis. In airway epithelial cells, we also showed that the activation of Akt by a small molecule (SC79) enhances NO production and increases levels of nuclear Nrf2, which reduces IL-8 transcription during concomitant stimulation with Toll-like receptor (TLR) 5 agonist flagellin. We hypothesized that SC79's production of NO in macrophages might likewise enhance phagocytosis and reduce the transcription of some pro-inflammatory cytokines. Using live cell imaging of fluorescent biosensors and indicator dyes, we found that SC79 induces Akt activation, NO production, and downstream cGMP production in primary human M0 macrophages. This was accompanied by a reduction in IL-6, IL-8, and IL-12 production during concomitant stimulation with bacterial lipopolysaccharide, an agonist of pattern recognition receptors including TLR4. Pharmacological inhibitors suggested that this effect was dependent on Akt and Nrf2. Together, these data suggest that several macrophage immune pathways are regulated by SC79 via Akt. A small-molecule Akt activator may be useful in some infection settings, warranting future in vivo studies.

Background Sinonasal mucosa in patients with chronic rhinosinusitis (CRS) is often devoid of motile cilia. This defect is presumed to result from prolonged inflammation, infection, or both. However, the mechanism underlying this observation is unknown. Recently, centrosomal protein 110 (Cp110) was shown to prevent the terminal step in ciliary maturation (ie, elongation), suggesting that Cp110 might be involved in pathological states in which ciliation is abnormal. Objectives First, we sought to investigate the expression of Cp110 in sinonasal mucosa from patients with CRS and control subjects. Second, we sought to determine the extent that inflammatory cytokines modulate Cp110 expression and ciliary maturation in vitro . Methods Sinonasal mucosal specimens from patients with and without CRS were analyzed for Cp110 mRNA and protein expression. Furthermore, human and murine nasal respiratory epithelial cultures were used to investigate Cp110 expression under normal growth conditions and in the presence of exogenous proinflammatory cytokines. Results Increased Cp110 mRNA and protein expression was found in sinonasal mucosal specimens from patients with CRS compared with that seen in control specimens. During ciliogenesis in vitro , the expression of Cp110 gradually decreased in cultures derived from patients without CRS but remained increased in cultures derived from patients with CRS. Furthermore, cultures grown in the presence of proinflammatory cytokines demonstrated increased levels of Cp110 expression with concomitant inhibition of ciliogenesis. Conclusion Increased Cp110 expression in mucosa from patients with CRS might contribute to the poor ciliation observed in patients with CRS. Exogenous cytokine exposure maintains increased levels of Cp110 expression. Regulation of Cp110 expression by inflammation warrants additional investigation because it might offer a novel target in the management of respiratory tract diseases. [ABSTRACT FROM AUTHOR]

Background: Patients with aspirin‐exacerbated respiratory disease (AERD) are among the most challenging rhinologic patients to treat. AERD has a complex inflammatory milieu of lipid mediators and cytokines. In this study we evaluated cytokine differences in the complex AERD environment at the mucus, epithelial, and tissue levels. Methods: Samples were acquired at the time of sinus surgery from 21 patients (seven steroid‐treated, 14 untreated) with aspirin challenge‐confirmed AERD. Three methods (sponge adsorption, epithelial brushing, tissue biopsy) were used to acquire samples from the respective sinus sampling sites (mucus, polyp epithelium, and full‐thickness polyp) of each patient. We measured and compared 16 cytokine concentrations in AERD patients with or without prednisone treatment using the Luminex platform. Results: In most sampling sites, IL‐5, IL‐6, IL‐10, IL‐13, IL‐33, CCL20, and TNF‐α were detected at higher concentrations than IFN‐γ, IL‐1β, IL‐17A, IL‐4, IL‐22, IL‐17E/IL25, and GM‐CSF. Each sampling site had a different pattern of cytokine levels, and except for IL‐5 and IL‐25 there was no correlation among sampling methods for each cytokine tested. The most notable and significant decreases in cytokines from those treated with prednisone were observed in the epithelium for IL‐5, IL‐10, IL‐33, and IFN‐γ. Conclusions: In the epithelial samples, type 2‐associated cytokines IL‐5 and IL‐33, the anti‐inflammatory cytokine IL‐10, and IFN‐γ were lower in AERD patients treated with prednisone. This work serves as a basis to assess therapeutic‐induced mucosal cytokine responses in AERD and indicates that the site of cytokine measurement is an important consideration when assessing results. [ABSTRACT FROM AUTHOR]