@article{SchuetzJurastowBaderetal.2015, author = {Sch{\"u}tz, Burkhard and Jurastow, Innokentij and Bader, Sandra and Ringer, Cornelia and Engelhardt, Jakob von and Chubanov, Vladimir and Gudermann, Thomas and Diener, Martin and Kummer, Wolfgang and Krasteva-Christ, Gabriela and Weihe, Eberhard}, title = {Chemical coding and chemosensory properties of cholinergic brush cells in the mouse gastrointestinal and biliary tract}, series = {Frontiers in Physiology}, volume = {6}, journal = {Frontiers in Physiology}, number = {87}, doi = {10.3389/fphys.2015.00087}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-143550}, year = {2015}, abstract = {The mouse gastro-intestinal and biliary tract mucosal epithelia harbor choline acetyltransferase (ChAT)-positive brush cells with taste cell-like traits. With the aid of two transgenic mouse lines that express green fluorescent protein (EGFP) under the control of the ChAT promoter (EGFP\(^{ChAT}\)) and by using in situ hybridization and immunohistochemistry we found that EGFP\(^{ChAT}\) cells were clustered in the epithelium lining the gastric groove. EGFP\(^{ChAT}\) cells were numerous in the gall bladder and bile duct, and found scattered as solitary cells along the small and large intestine. While all EGFP\(^{ChAT}\) cells were also ChAT-positive, expression of the high-affinity choline transporter (ChT1) was never detected. Except for the proximal colon, EGFP\(^{ChAT}\) cells also lacked detectable expression of the vesicular acetylcholine transporter (VAChT). EGFP\(^{ChAT}\) cells were found to be separate from enteroendocrine cells, however they were all immunoreactive for cytokeratin 18 (CK18), transient receptor potential melastatin-like subtype 5 channel (TRPM5), and for cyclooxygenases 1 (COX1) and 2 (COX2). The ex vivo stimulation of colonic EGFP\(^{ChAT}\) cells with the bitter substance denatonium resulted in a strong increase in intracellular calcium, while in other epithelial cells such an increase was significantly weaker and also timely delayed. Subsequent stimulation with cycloheximide was ineffective in both cell populations. Given their chemical coding and chemosensory properties, EGFP\(^{ChAT}\) brush cells thus may have integrative functions and participate in induction of protective reflexes and inflammatory events by utilizing ACh and prostaglandins for paracrine signaling.}, language = {en} } @article{HollenhorstJurastowNandigamaetal.2020, author = {Hollenhorst, Monika I. and Jurastow, Innokentij and Nandigama, Rajender and Appenzeller, Silke and Li, Lei and Vogel, J{\"o}rg and Wiederhold, Stephanie and Althaus, Mike and Empting, Martin and Altm{\"u}ller, Janine and Hirsch, Anna K. H. and Flockerzi, Veit and Canning, Brendan J. and Saliba, Antoine-Emmanuel and Krasteva-Christ, Gabriela}, title = {Tracheal brush cells release acetylcholine in response to bitter tastants for paracrine and autocrine signaling}, series = {The FASEB Journal}, volume = {34}, journal = {The FASEB Journal}, number = {1}, doi = {10.1096/fj.201901314RR}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-213516}, pages = {316 -- 332}, year = {2020}, abstract = {For protection from inhaled pathogens many strategies have evolved in the airways such as mucociliary clearance and cough. We have previously shown that protective respiratory reflexes to locally released bacterial bitter "taste" substances are most probably initiated by tracheal brush cells (BC). Our single-cell RNA-seq analysis of murine BC revealed high expression levels of cholinergic and bitter taste signaling transcripts (Tas2r108, Gnat3, Trpm5). We directly demonstrate the secretion of acetylcholine (ACh) from BC upon stimulation with the Tas2R agonist denatonium. Inhibition of the taste transduction cascade abolished the increase in [Ca\(^{2+}\)]\(_{i}\) in BC and subsequent ACh-release. ACh-release is regulated in an autocrine manner. While the muscarinic ACh-receptors M3R and M1R are activating, M2R is inhibitory. Paracrine effects of ACh released in response to denatonium included increased [Ca\(^{2+}\)]\(_{i}\) in ciliated cells. Stimulation by denatonium or with Pseudomonas quinolone signaling molecules led to an increase in mucociliary clearance in explanted tracheae that was Trpm5- and M3R-mediated. We show that ACh-release from BC via the bitter taste cascade leads to immediate paracrine protective responses that can be boosted in an autocrine manner. This mechanism represents the initial step for the activation of innate immune responses against pathogens in the airways.}, language = {en} }