{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T01:09:03Z","timestamp":1792804143711,"version":"4.5.0"},"reference-count":38,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2025,9,12]],"date-time":"2025-09-12T00:00:00Z","timestamp":1757635200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union\u2014Next Generation EU, Mission 6, Component 2","award":["CUP F93C24000310005"],"award-info":[{"award-number":["CUP F93C24000310005"]}]},{"name":"project \u201cINSPIRER\u201d","award":["CUP F93C24000310005"],"award-info":[{"award-number":["CUP F93C24000310005"]}]},{"name":"Fondazione Cassa di Risparmio di Modena (Neurobiobanca di Modena)","award":["CUP F93C24000310005"],"award-info":[{"award-number":["CUP F93C24000310005"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Mitochondrial dysfunction is a key pathological hallmark in amyotrophic lateral sclerosis (ALS), yet the role of circulating cell-free mitochondrial DNA (Cf-mtDNA) as a biomarker remains unclear. This study aimed to investigate serum Cf-mtDNA levels in ALS patients compared to healthy controls and explore its associations with disease biomarkers, clinical progression, and survival. We conducted a case\u2013control study measuring Cf-mtDNA levels in serum samples from 54 ALS patients and 36 age- and sex-matched healthy controls using quantitative droplet digital PCR. Correlations between Cf-mtDNA levels and clinical features, neurofilament concentrations, inflammatory indices, and survival were assessed. The average Cf-mtDNA level in ALS patients was 2,426,315 copies\/mL of serum (IQR: 865000\u20132475000), compared to 1,885,667 copies\/mL of serum (IQR: 394250\u20132492500) in controls (p = 0.308). ROC analysis yielded an AUC of 0.595 (95% CI: 0.468\u20130.721), indicating very limited discriminant ability. Cf-mtDNA levels were inversely correlated with serum creatinine concentrations (r = \u20130.335, p = 0.018), but showed no significant associations with ALS phenotype, disease staging, neurofilaments, inflammatory indices, or survival. These findings suggest that, in a predominantly sporadic ALS cohort, serum Cf-mtDNA may not serve as a standalone diagnostic or prognostic biomarker, in contrast to previous reports. Methodological differences, cohort composition, and genetic heterogeneity may account for these discrepancies. Our results underscore the importance of further large-scale, longitudinal studies incorporating genetic stratification and multi-biomarker approaches to better elucidate the role of Cf-mtDNA in ALS pathophysiology.<\/jats:p>","DOI":"10.3390\/cells14181433","type":"journal-article","created":{"date-parts":[[2025,9,15]],"date-time":"2025-09-15T07:56:51Z","timestamp":1757923011000},"page":"1433","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Circulating Serum Cell-Free Mitochondrial DNA in Amyotrophic Lateral Sclerosis"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6285-4314","authenticated-orcid":false,"given":"Giada","family":"Zanini","sequence":"first","affiliation":[{"name":"Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ilaria","family":"Martinelli","sequence":"additional","affiliation":[{"name":"Department of Neurosciences, Ospedale Civile di Baggiovara, Azienda Ospedaliero-Universitaria di Modena, 41126 Modena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giorgia","family":"Sinigaglia","sequence":"additional","affiliation":[{"name":"Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elisabetta","family":"Zucchi","sequence":"additional","affiliation":[{"name":"Department of Neurosciences, Ospedale Civile di Baggiovara, Azienda Ospedaliero-Universitaria di Modena, 41126 Modena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0499-2505","authenticated-orcid":false,"given":"Federico","family":"Banchelli","sequence":"additional","affiliation":[{"name":"Department of Neurosciences, Ospedale Civile di Baggiovara, Azienda Ospedaliero-Universitaria di Modena, 41126 Modena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5456-2365","authenticated-orcid":false,"given":"Cecilia","family":"Simonini","sequence":"additional","affiliation":[{"name":"Department of Neurosciences, Ospedale Civile di Baggiovara, Azienda Ospedaliero-Universitaria di Modena, 41126 Modena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4260-0915","authenticated-orcid":false,"given":"Giulia","family":"Gianferrari","sequence":"additional","affiliation":[{"name":"Department of Neurosciences, Ospedale Civile di Baggiovara, Azienda Ospedaliero-Universitaria di Modena, 41126 Modena, Italy"},{"name":"Neuroscience PhD Program, Department of Biomedical, Metabolic, and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea","family":"Ghezzi","sequence":"additional","affiliation":[{"name":"Department of Neurosciences, Ospedale Civile di Baggiovara, Azienda Ospedaliero-Universitaria di Modena, 41126 Modena, Italy"},{"name":"Neuroscience PhD Program, Department of Biomedical, Metabolic, and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9244-9782","authenticated-orcid":false,"given":"Jessica","family":"Mandrioli","sequence":"additional","affiliation":[{"name":"Department of Neurosciences, Ospedale Civile di Baggiovara, Azienda Ospedaliero-Universitaria di Modena, 41126 Modena, Italy"},{"name":"Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9118-1262","authenticated-orcid":false,"given":"Marcello","family":"Pinti","sequence":"additional","affiliation":[{"name":"Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Genin, E.C., Abou-Ali, M., and Paquis-Flucklinger, V. 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