{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T14:58:08Z","timestamp":1789743488466,"version":"4.0.1"},"reference-count":73,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2021,6,6]],"date-time":"2021-06-06T00:00:00Z","timestamp":1622937600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>Recent studies support the hypothesis that microbes can seed some Alzheimer\u2019s disease (AD) cases, leading to inflammation and overproduction of amyloid peptides. Porphyromonas gingivalis (Pg) is a keystone pathogen of chronic periodontitis and has been identified as risk factor for the development and progression of AD. The present preliminary study aimed to quantify Pg abundance in neurodegenerative disease (ND) patients compared with neurologic patients without neurodegenerative disorders (no-ND) and healthy controls (HC) to determine possible association between Pg abundance and neurodegenerative process. Pg was quantified on DNA extracted from the oral samples of 49 patients and 29 HC by quantitative polymerase chain reaction (qPCR). Anti-Pg antibodies were also detected on patient serum samples by enzyme-linked immunosorbent assays (ELISA). The Pg abundance in the oral cavity was significantly different among groups (p = 0.004). It was higher in ND than no-ND (p = 0.010) and HC (p = 0.008). The Pg abundance was correlated with the antibodies (p = 0.001) with different slopes between ND and no-ND (p = 0.037). Pg abundance was not correlated with oral indices and comorbidities. These results extend our understanding of the association between oral pathogens and AD to other neurodegenerative processes, confirming the hypothesis that oral pathogens can induce an antibody systemic response, influencing the progression of the disease.<\/jats:p>","DOI":"10.3390\/biom11060845","type":"journal-article","created":{"date-parts":[[2021,6,6]],"date-time":"2021-06-06T23:59:55Z","timestamp":1623023995000},"page":"845","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":33,"title":["Exploring the Connection between Porphyromonas gingivalis and Neurodegenerative Diseases: A Pilot Quantitative Study on the Bacterium Abundance in Oral Cavity and the Amount of Antibodies in Serum"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8819-1061","authenticated-orcid":false,"given":"Raffaella","family":"Franciotti","sequence":"first","affiliation":[{"name":"Department of Neuroscience, Imaging and Clinical Sciences, \u201cG. d\u2019Annunzio\u201d University of Chieti-Pescara, 66013 Chieti, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3023-7143","authenticated-orcid":false,"given":"Pamela","family":"Pignatelli","sequence":"additional","affiliation":[{"name":"Department of Medical, Oral and Biotechnological Sciences, \u201cG. d\u2019Annunzio\u201d University of Chieti-Pescara, 66013 Chieti, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Claudia","family":"Carrarini","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Imaging and Clinical Sciences, \u201cG. d\u2019Annunzio\u201d University of Chieti-Pescara, 66013 Chieti, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Federica Maria","family":"Romei","sequence":"additional","affiliation":[{"name":"Department of Medical, Oral and Biotechnological Sciences, \u201cG. d\u2019Annunzio\u201d University of Chieti-Pescara, 66013 Chieti, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martina","family":"Mastrippolito","sequence":"additional","affiliation":[{"name":"Department of Medical, Oral and Biotechnological Sciences, \u201cG. d\u2019Annunzio\u201d University of Chieti-Pescara, 66013 Chieti, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonella","family":"Gentile","sequence":"additional","affiliation":[{"name":"Department of Medical, Oral and Biotechnological Sciences, \u201cG. d\u2019Annunzio\u201d University of Chieti-Pescara, 66013 Chieti, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rosa","family":"Mancinelli","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Imaging and Clinical Sciences, \u201cG. d\u2019Annunzio\u201d University of Chieti-Pescara, 66013 Chieti, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4557-9127","authenticated-orcid":false,"given":"Stefania","family":"Fulle","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Imaging and Clinical Sciences, \u201cG. d\u2019Annunzio\u201d University of Chieti-Pescara, 66013 Chieti, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adriano","family":"Piattelli","sequence":"additional","affiliation":[{"name":"Department of Medical, Oral and Biotechnological Sciences, \u201cG. d\u2019Annunzio\u201d University of Chieti-Pescara, 66013 Chieti, Italy"},{"name":"Fondazione Villa Serena per la Ricerca, Citt\u00e0 S. Angelo, 65013 Pescara, Italy"},{"name":"Casa di Cura \u201cVilla Serena\u201d del Dott. L. Petruzzi, Citt\u00e0 S. 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