{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T10:10:14Z","timestamp":1776075014777,"version":"3.50.1"},"reference-count":29,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T00:00:00Z","timestamp":1776038400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medical Sciences"],"abstract":"<jats:p>Background: In Parkinson\u2019s disease (PD), changes in the brain begin before clinical symptoms. We have previously shown that VGF precursor levels were reduced in a presymptomatic PD animal model. Objectives: In the present study, we investigated whether two VGF precursor-derived products, namely NAPP-129 protein and TLQP-62 peptide, also exhibit alterations using the same PD animal model. Methods: Specifically, rats were unilaterally injected in the substantia nigra with a viral vector overexpressing green fluorescent protein (N = 12) or \u03b1-synuclein (N = 13), the latter resulting in mild dopaminergic alterations without overt motor deficits. Results: NAPP-129 and TLQP-62 were investigated in the substantia nigra, striatum, and plasma by Western blotting or immunoassays using specific antibodies against NAPP and TLQP sequences, alongside other NERP-1- and AQEE-related products. Plasma samples of a Huntington\u2019s disease mouse model were also analyzed. We found reductions in NAPP-129 and TLQP-62 levels in the substantia nigra along with a decrease in NAPP- and TLQP-like plasma immunoreactivity in \u03b1-synuclein-overexpressed rats, while the striatum was not affected. NERP-1- and AQEE-related products were not altered. No changes were found in the Huntington\u2019s disease model. Conclusions: These findings indicate that NAPP-129 and TLQP-62 may enhance the sensitivity and specificity of biomarker-based strategies for PD.<\/jats:p>","DOI":"10.3390\/medsci14020195","type":"journal-article","created":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T08:49:02Z","timestamp":1776070142000},"page":"195","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Effect of \u03b1-Synuclein Overexpression on NAPP-129 and TLQP-62 in Rat Brain and Plasma"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0606-5636","authenticated-orcid":false,"given":"Antonio Luigi","family":"Manai","sequence":"first","affiliation":[{"name":"Department of Biomedical Sciences, University of Cagliari, 09042 Monserrato, CA, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-8312-2143","authenticated-orcid":false,"given":"Barbara","family":"Noli","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences, University of Cagliari, 09042 Monserrato, CA, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-8147-8182","authenticated-orcid":false,"given":"Aqsa","family":"Anjum","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences, University of Cagliari, 09042 Monserrato, CA, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elias","family":"Manca","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences, University of Cagliari, 09042 Monserrato, CA, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0367-832X","authenticated-orcid":false,"given":"Maria Antonietta","family":"Casu","sequence":"additional","affiliation":[{"name":"National Research Council-Institute of Translational Pharmacology, 09050 Pula, CA, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4737-9479","authenticated-orcid":false,"given":"Marie-Christine","family":"Pardon","sequence":"additional","affiliation":[{"name":"School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3915-208X","authenticated-orcid":false,"given":"Cristina","family":"Cocco","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences, University of Cagliari, 09042 Monserrato, CA, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"R183","DOI":"10.1093\/hmg\/ddm159","article-title":"Parkinson\u2019s disease","volume":"16","author":"Thomas","year":"2007","journal-title":"Hum. 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