{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T03:51:39Z","timestamp":1783569099613,"version":"3.55.0"},"reference-count":38,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2024,12,6]],"date-time":"2024-12-06T00:00:00Z","timestamp":1733443200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003196","name":"Italian Ministry of Health","doi-asserted-by":"publisher","award":["RC n. 278705"],"award-info":[{"award-number":["RC n. 278705"]}],"id":[{"id":"10.13039\/501100003196","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>More than six million people worldwide are affected by Parkinson\u2019s disease (PD), a multifactorial disorder characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta (SNc). Several immunohistochemical studies suggest that neuromelanin (NM), found in these neurons, plays a key role in their degeneration. In this study, twelve formalin-fixed, paraffin-embedded (FFPE) brain sections were analyzed, comprising six samples from PD patients and six from healthy controls. Immunohistochemistry (IHC) was conducted to assess the expression of the ETNPPL protein in these samples. ETNPPL was detected in both PD and control samples. Additionally, we examined the expression of ETNPPL mRNA using Quantitative Real-Time PCR (qRT-PCR) in the same sample set. Notably, in control samples, ETNPPL protein was closely associated with the dark NM pigment in the cytoplasm of SNc dopaminergic neurons. In contrast, PD samples showed weak cytoplasmic expression of ETNPPL, with no association with the NM pigment. No nuclear ETNPPL signal was detected in dopaminergic neurons from either PD patients or controls. qRT-PCR results revealed lower ETNPPL mRNA expression in individual PD patients compared to controls. Importantly, we observed a higher concentration of ETNPPL protein at the NM level in the SNc neurons of controls, consistent with mRNA expression patterns. These findings suggest a potential role for ETNPPL in the normal function of dopaminergic neurons and underscore its altered expression in Parkinson\u2019s disease.<\/jats:p>","DOI":"10.3390\/ijms252313107","type":"journal-article","created":{"date-parts":[[2024,12,6]],"date-time":"2024-12-06T03:44:47Z","timestamp":1733456687000},"page":"13107","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["The Role of ETNPPL in Dopaminergic Neuron Stability: Insights from Neuromelanin-Associated Protein Expression in Parkinson\u2019s Disease"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-7185-1176","authenticated-orcid":false,"given":"Francesca A.","family":"Schillaci","sequence":"first","affiliation":[{"name":"Oasi Research Institute-IRCCS, 94018 Troina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5659-662X","authenticated-orcid":false,"given":"Giuseppe","family":"Lanza","sequence":"additional","affiliation":[{"name":"Oasi Research Institute-IRCCS, 94018 Troina, Italy"},{"name":"Department of Surgery and Medical-Surgical Specialties, University of Catania, 95125 Catania, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6240-1975","authenticated-orcid":false,"given":"Maria Grazia","family":"Salluzzo","sequence":"additional","affiliation":[{"name":"Oasi Research Institute-IRCCS, 94018 Troina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3292-9677","authenticated-orcid":false,"given":"Francesca","family":"L\u2019Episcopo","sequence":"additional","affiliation":[{"name":"Oasi Research Institute-IRCCS, 94018 Troina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6937-3065","authenticated-orcid":false,"given":"Raffaele","family":"Ferri","sequence":"additional","affiliation":[{"name":"Oasi Research Institute-IRCCS, 94018 Troina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michele","family":"Salemi","sequence":"additional","affiliation":[{"name":"Oasi Research Institute-IRCCS, 94018 Troina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"385","DOI":"10.1016\/S1474-4422(21)00030-2","article-title":"Challenges in the Diagnosis of Parkinson\u2019s Disease","volume":"20","author":"Tolosa","year":"2021","journal-title":"Lancet Neurol."},{"key":"ref_2","first-page":"451","article-title":"Parkinson\u2019s Disease Is Predominantly an Environmental Disease","volume":"14","author":"Dorsey","year":"2024","journal-title":"J. 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