{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:08:54Z","timestamp":1760148534996,"version":"build-2065373602"},"reference-count":43,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2023,5,6]],"date-time":"2023-05-06T00:00:00Z","timestamp":1683331200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Italian Ministry of Health","award":["5mille15D7","RC15\/17","RC 29\/23","101007417"],"award-info":[{"award-number":["5mille15D7","RC15\/17","RC 29\/23","101007417"]}]},{"name":"European Union\u2019s Horizon 2020 framework for research and innovation","award":["5mille15D7","RC15\/17","RC 29\/23","101007417"],"award-info":[{"award-number":["5mille15D7","RC15\/17","RC 29\/23","101007417"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>In this study, we revealed a peculiar morphological feature of 50B11 nociceptive sensory neurons in in vitro culture related to the forskolin-induced differentiation of these cells growing upside-down on cover glass supports. Multi-photon non-linear microscopy was applied to monitor increased neurite arborization and elongation. Under live and unstained conditions, second harmonic generation (SHG) microscopy could monitor microtubule organization inside the cells while also correlating with the detection of cellular multi-photon autofluorescence, probably derived from mitochondria metabolites. Although the differentiated cells of each compartment did not differ significantly in tubulin or multi-photon autofluorescence contents, the upturned neurons were more elongated, presenting a higher length\/width cellular ratio and longer neurites, indicative of differentiated cells. SHG originating from the axons\u2019 microtubules represented a proper tool to study neurons\u2019 inverted culture in live conditions without exogenous staining. This work represents the first instance of examining neuronal cell lines growing and differentiated in an upside-down orientation, allowing a possible improvement of 50B11 as a model in physiology studies of sensory neurons in peripheric nervous system disease (e.g., Fabry disease, Friedreich ataxia, Charcot\u2013Marie\u2013Tooth, porphyria, type 1 diabetes, Guillain\u2013Barr\u00e9 syndrome in children) and analgesic drug screening.<\/jats:p>","DOI":"10.3390\/ijms24098354","type":"journal-article","created":{"date-parts":[[2023,5,8]],"date-time":"2023-05-08T03:34:53Z","timestamp":1683516893000},"page":"8354","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Upside-Down Preference in the Forskolin-Induced In Vitro Differentiation of 50B11 Sensory Neurons: A Morphological Investigation by Label-Free Non-Linear Microscopy"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5886-9129","authenticated-orcid":false,"given":"Luisa","family":"Zupin","sequence":"first","affiliation":[{"name":"Institute for Maternal and Child Health IRCCS Burlo Garofolo, 34137 Trieste, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sotiris","family":"Psilodimitrakopoulos","sequence":"additional","affiliation":[{"name":"Institute of Electronic Structure and Laser, Foundation for Research and Technology\u2014Hellas, 70013 Heraklion, Crete, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9760-8463","authenticated-orcid":false,"given":"Fulvio","family":"Celsi","sequence":"additional","affiliation":[{"name":"Institute for Maternal and Child Health IRCCS Burlo Garofolo, 34137 Trieste, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8082-7486","authenticated-orcid":false,"given":"Lina","family":"Papadimitriou","sequence":"additional","affiliation":[{"name":"Institute of Electronic Structure and Laser, Foundation for Research and Technology\u2014Hellas, 70013 Heraklion, Crete, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5034-6267","authenticated-orcid":false,"given":"Anthi","family":"Ranella","sequence":"additional","affiliation":[{"name":"Institute of Electronic Structure and Laser, Foundation for Research and Technology\u2014Hellas, 70013 Heraklion, Crete, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8493-1168","authenticated-orcid":false,"given":"Sergio","family":"Crovella","sequence":"additional","affiliation":[{"name":"Biological Science Program, Department of Biological and Environmental Sciences, College of Arts and Sciences, University of Qatar, Doha 2713, Qatar"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8031-1102","authenticated-orcid":false,"given":"Giuseppe","family":"Ricci","sequence":"additional","affiliation":[{"name":"Institute for Maternal and Child Health IRCCS Burlo Garofolo, 34137 Trieste, Italy"},{"name":"Department of Medicine, Surgery and Health Sciences, University of Trieste, 34129 Trieste, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1908-8618","authenticated-orcid":false,"given":"Emmanuel","family":"Stratakis","sequence":"additional","affiliation":[{"name":"Institute of Electronic Structure and Laser, Foundation for Research and Technology\u2014Hellas, 70013 Heraklion, Crete, Greece"},{"name":"Department of Physics, School of Sciences and Engineering, University of Crete, 71003 Heraklion, Crete, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1044-7263","authenticated-orcid":false,"given":"Lorella","family":"Pascolo","sequence":"additional","affiliation":[{"name":"Institute for Maternal and Child Health IRCCS Burlo Garofolo, 34137 Trieste, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"242","DOI":"10.1016\/j.spen.2016.10.008","article-title":"Neuropathic and Myopathic Pain","volume":"23","author":"Rodrigues","year":"2016","journal-title":"Semin. 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