In the epithelium of the lower airways, a cell type of unknown function has been termed "brush cell" because of a distinctive ultrastructural feature, an apical tuft of microvilli. Morphologically similar cells in the nose have been identified as solitary chemosensory cells responding to taste stimuli and triggering trigeminal reflexes. Here we show that brush cells of the mouse trachea express the receptors (Tas2R105, Tas2R108), the downstream signaling molecules (α-gustducin, phospholipase C β2 ) of bitter taste transduction, the synthesis and packaging machinery for acetylcholine, and are addressed by vagal sensory nerve fibers carrying nicotinic acetylcholine receptors. Tracheal application of an nAChR agonist caused a reduction in breathing frequency. Similarly, cycloheximide, a Tas2R108 agonist, evoked a drop in respiratory rate, being sensitive to nicotinic receptor blockade and epithelium removal. This identifies brush cells as cholinergic sensors of the chemical composition of the lower airway luminal microenvironment that are directly linked to the regulation of respiration.airway sensory innervation | respiratory epithelium | jugular-nodose ganglion | bitter-tasting substances
Background-Atherosclerosis is a chronic inflammatory vascular disease driven by the subendothelial accumulation of macrophages. The mechanism regulating the inflammatory response in macrophages during atherogenesis remains unclear. Because microRNAs (miRNAs) play a crucial role in cellular signaling by posttranscriptional regulation of gene expression, we studied the miRNA expression profiles during the progression of atherosclerosis. Methods and Results-Using an miRNA real-time polymerase chain reaction array, we found that macrophage-derived miR-342-5p and miR-155 are selectively upregulated in early atherosclerotic lesions in Apoe −/− mice. miR-342-5p directly targets Akt1 through its 3ʹ-untranslated region. Akt1 suppression by miR-342-5p induces proinflammatory mediators such as Nos2 and II6 in macrophages via the upregulation of miR-155. The local application of an miR-342-5p antagomir inhibits the development of atherosclerosis in partially ligated carotid arteries. In atherosclerotic lesions, the miR-342-5p antagomir upregulated Akt1 expression and suppressed the expression of miR-155 and Nos2. This reduced Nos2 expression was associated with a diminished generation of nitrotyrosine in the plaques. Furthermore, systemic treatment with an inhibitor of miR-342-5p reduced the progression of atherosclerosis in the aorta of Apoe −/− mice. miR-223, miR-155, and miR-146a govern the proinflamma tory activation of macrophages by regulating the nuclear factor-κB signaling pathway. 9,15 The atherogenic stimulation of monocytes and macrophages by oxidized low-density lipoprotein also alters the miRNA expression profile, including the expression of miR-155 and miR-146a; this, in turn, affects lipid uptake and inflammatory cytokine secretion. 16 Moreover, inhibition of miR-33 causes an increase in reverse cholesterol transport, thereby reducing atherosclerosis and inflammatory gene expression. Conclusions-Macrophage-derived miR-342-5p 17Thus, miRNAs may be crucial for the regulation of inflammatory and lipid-handling functions in lesional macrophages. However, the miRNAs that control the inflammatory response during atherosclerosis have not been identified.In this study, we generated stage-specific miRNA expression profiles in atherosclerotic lesions from Apoe −/− mice. During early atherosclerosis, the most prominently upregulated miRNA was miR-342-5p, which is expressed in lesional macrophages. On proinflammatory activation in macrophages in vitro, miR-342-5p promoted Nos2 expression in an miR-155-dependent manner by targeting Akt1, an inhibitor of miR-155 expression. Accordingly, the inhibition of miR-342-5p reduced atherosclerotic lesion formation and suppressed Akt1-dependent Nos2 expression in lesional macrophages. Taken together, these data demonstrate a crucial role for miR-342-5p in the early inflammatory response in lesional macrophages. Methods Animal ModelsApoe −/− mice (age, 6-8 weeks; The Jackson Laboratory, Bar Harbor, ME) were fed a high-cholesterol diet (HCD; Altromin, Germany) comprising 21% crude ...
This is the second Nurse European Crohns and Colitis (N-ECCO) consensus statements document addressing inflammatory bowel disease (IBD) nursing across Europe. N-ECCO continues to be an active member of European Crohns and Colitis Organisation (ECCO), providing education and networking opportunities for nurses across Europe within three designated nurse sessions, N-ECCO Network Meeting, N-ECCO School and the N-ECCO Research Forum, in addition to e-learning and podcasts. 1.1 Aim The over-arching aim of ECCO is to improve the care of patients with IBD through the development of guidelines, education and research. Current evidence is fundamental to enable N-ECCO to meet this progressive aim. This document updates the first N-ECCO consensus statements based on the 'ideal' standard of care [1], and provides additional statements and evidence supporting contemporary IBD nursing practice, whilst acknowledging the extensive variety in IBD nursing practice across Europe [2].
Chemokines mediate monocyte adhesion to dysfunctional endothelial cells (ECs) and promote arterial inflammation during atherosclerosis. Hypoxia-inducible factor (HIF)-1α is expressed in various cell types of atherosclerotic lesions and is associated with lesional inflammation. However, the impact of endothelial HIF-1α in atherosclerosis is unclear. HIF-1α was detectable in the nucleus of ECs covering murine and human atherosclerotic lesions. To study the role of endothelial HIF-1α in atherosclerosis, deletion of the Hif1 a gene was induced in ECs from apolipoprotein E knockout mice (EC- Hif1a −/− ) by Tamoxifen injection. The formation of atherosclerotic lesions, the lesional macrophage accumulation, and the expression of CXCL1 in ECs were reduced after partial carotid ligation in EC- Hif1a −/− compared with control mice. Moreover, the lesion area and the lesional macrophage accumulation were decreased in the aortas of EC- Hif1a −/− mice compared with control mice during diet-induced atherosclerosis. In vitro, mildly oxidized low-density lipoprotein or lysophosphatidic acid 20:4 increased endothelial CXCL1 expression and monocyte adhesion by inducing HIF-1α expression. Moreover, endothelial Hif1a deficiency resulted in downregulation of miR-19a in atherosclerotic arteries determined by microRNA profiling. In vitro, HIF-1α–induced miR-19a expression mediated the upregulation of CXCL1 in mildly oxidized low-density lipoprotein–stimulated ECs. These results indicate that hyperlipidemia upregulates HIF-1α expression in ECs by mildly oxidized low-density lipoprotein–derived unsaturated lysophosphatidic acid. Endothelial HIF-1α promoted atherosclerosis by triggering miR-19a–mediated CXCL1 expression and monocyte adhesion, indicating that inhibition of the endothelial HIF-1α/miR-19a pathway may be a therapeutic option against atherosclerosis.
Ciliary beating of airway epithelial cells drives the removal of mucus and particles from the airways. Mucociliary transport and possibly airway epithelial development are governed by muscarinic acetylcholine receptors but the precise roles of the subtypes involved are unknown. This issue was addressed by determining cilia-driven particle transport, ciliary beat frequency, and the composition and ultrastructural morphology of the tracheal epithelium in M1–M5 muscarinic receptor gene-deficient mice. Knockout of M3 muscarinic receptors prevented an increase in particle transport speed and ciliary beat frequency in response to muscarine. Furthermore, the ATP response after application of muscarine was blunted. Pretreatment with atropine before application of muscarine restored the response to ATP. Additional knockout of the M2 receptor in these mice partially restored the muscarine effect most likely through the M1 receptor and normalized the ATP response. M1, M4, and M5 receptor deficient mice exhibited normal responses to muscarine. None of the investigated mutant mouse strains had any impairment of epithelial cellular structure or composition. In conclusion, M3 receptors stimulate whereas M2 receptors inhibit cilia-driven particle transport. The M1 receptor increases cilia-driven particle transport if the M3 and M2 receptor are missing. None of the receptors is necessary for epithelial development.
MicroRNAs regulate the maladaptation of endothelial cells (ECs) to naturally occurring disturbed blood flow at arterial bifurcations resulting in arterial inflammation and atherosclerosis in response to hyperlipidemic stress. Here, we show that reduced endothelial expression of the RNAse Dicer, which generates almost all mature miRNAs, decreases monocyte adhesion, endothelial C–X–C motif chemokine 1 (CXCL1) expression, atherosclerosis and the lesional macrophage content in apolipoprotein E knockout mice (Apoe−/−) after exposure to a high-fat diet. Endothelial Dicer deficiency reduces the expression of unstable miRNAs, such as miR-103, and promotes Krüppel-like factor 4 (KLF4)-dependent gene expression in murine atherosclerotic arteries. MiR-103 mediated suppression of KLF4 increases monocyte adhesion to ECs by enhancing nuclear factor-κB-dependent CXCL1 expression. Inhibiting the interaction between miR-103 and KLF4 reduces atherosclerosis, lesional macrophage accumulation and endothelial CXCL1 expression. Overall, our study suggests that Dicer promotes endothelial maladaptation and atherosclerosis in part by miR-103-mediated suppression of KLF4.
The registry constitutes a large complemental database for the patient population in Germany. About one third of the IBD patients were not in clinical remission (CDAI ≥150/CAI >4) (CD: 45%; UC: 27%), although high rates of immunosuppressive drugs (CD: 47%; UC 26%) were administered. This study shows a large burden of active disease associated with an unexpectedly high (co)morbidity and high psychosocial impairments, indicating a reduced health state in IBD patients.
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