rdcjournalRoyal Dental College JournalE-Volume 8 Issue 1MultidisciplinaryEnglishJanuary- DecemberNNY20251114Periodontology Porphyromonas gingivalis and Alzheimer’s Disease: A Contemporary ReviewEnglishY7375Harish KumarVV1EnglishNSanthoshVC2EnglishYSaumiyaGopal2EnglishYNaseeba MohammedAli3EnglishY10.67091/JRDC.2025.8117                Alzheimer’s disease is a progressive neurodegenerative disorder characterized by cognitive decline and neuropathological hallmarks such as amyloid beta plaques and neurofibrillary tangles. In recent years, chronic infections have been proposed as potential contributors to Alzheimer’s disease pathogenesis. Periodontitis, a common chronic inflammatory condition, is predominantly associated with Porphyromonas gingivalis, a gram-negative anaerobic bacterium. Emerging evidence suggests that P. gingivalis may influence Alzheimer’s disease development through systemic inflammation, blood brain barrier disruption, and direct neurotoxic effects of its virulence factors. This review summarizes current evidence from experimental and clinical studies linking P. gingivalis with Alzheimer’s disease and discusses possible mechanisms and implications for future research.EnglishAlzheimer’s disease; Cytokines; Gingipains; Neurodegeneration; Porphyromonas gingivalishttps://www.rdcjournal.org/abstract?id=312References1619Dominy SS, Lynch C, Ermini F, Benedyk M, Marczyk A, Konradi A et al. Porphyromonas gingivalis in Alzheimerand;rsquo;s disease brains: Evidence for disease causation and treatment with small molecule inhibitors. Sci Adv.2019;5(1):eaau3333. doi:10.1126/sciadv.aau3333.Lei S, Li J, Yu J, Li F, Pan Y, Chen X et al. Porphyromonas gingivalis bacteremia increases the permeability of the blood-brain barrier via the Mfsd2a/Caveolin-1 mediated transcytosis pathway. Int J Oral Sci. 2023 Jan 12;15(1):3. doi: 10.1038/s41368-022-00215-y.Olsen I, Singhrao SK. Can Oral infection be a risk factor for Alzheimerand;rsquo;s disease. J Oral Microbiol. 2015;7:29143. doi: 10.3402/jom.v7.29143.Kamer AR, Craig RG, Dasanayake AP, Brys M, Glodzik-Sobanska L, de Leon MJ et al. Inflammation and Alzheimerand;rsquo;s disease: Possible role of periodontal diseases. Alzheimers Dement. 2008;4(4):242-250.doi:10.1016/j.jalz.2007.08.004.Ilievski V, Zuchowska PK, Green SJ, Toth PT, Ragozzino ME, Le K et al. Chronic oral application ofand;nbsp; a periodontaland;nbsp;pathogenand;nbsp;results in brain inflammation. PLoSand;nbsp; One.and;nbsp;2018;13(10):e0204941.doi:10.1371/journal.pone.02 04941.Dominy SS, Lynch C, Ermini F, Benedyk M, Marczyk A, Konradi A, et al. Porphyromonas gingivalis in Alzheimerand;#39;s disease brains: Evidence for disease causation and treatment with small-molecule inhibitors. Sci Adv. 2019 Janand;nbsp;23;5(1):eaau3333.and;nbsp;doi: 10.1126/sciadv.aau3333.Hajishengallis G, Lamont RJ. Polymicrobial communities in periodontal disease. Trends Microbiol. 2012;20(11):531and;ndash;538.Poole S, Singhrao SK, Kesavalu L, Curtis MA, Crean S. Determining the presence of periodontopathic virulence factors in Alzheimerand;rsquo;s disease brain tissue. J Alzheimers Dis. 2013;36(4):665and;ndash;677.Sarmiento Ordand;oacute;and;ntilde;ez R, Brito-Samaniego DR, Vand;aacute;squez-Palacios AC, Pacheco-Quito EM. Association between Porphyromonas gingivalis and Alzheimerand;rsquo;s Disease: A Comprehensive Review. Infect Drug Resist. 2025and;nbsp;and;nbsp; Aprand;nbsp;and;nbsp; 25;18:2119-2136.and;nbsp;and;nbsp; doi:10.2147/IDR.S491628.Nadim R, Tang J, Dilmohamed A, Yuan S, WU C, Bakre AT et al. Influence of periodontal disease on risk of dementia. J Am Geriatr Soc. 2020;68(11):2557and;ndash;2564.Ryder MI. Porphyromonas gingivalis and Alzheimer disease: Recent findings and potential therapies. J Periodontol. 2020 Oct;91 Suppl 1(Suppl 1):S45-S49. doi: 10.1002/JPER.20-0104.Tiisanoja A, Syrjand;auml;land;auml; AM, Komulainen K, et al. Periodontitis and cognitive decline. J Clin Periodontol. 2019;46(5):496and;ndash;505.Kamer AR, Morse DE, Holm Petersen J, et al. Periodontal disease and Alzheimerand;rsquo;s disease. Curr Oral Health Rep. 2022;9:75and;ndash;86.