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Kose O, Altin A, Kurt Bayrakdar S, Bostan SA, Mercantepe T, Akyildiz K, Tumkaya L, Yilmaz A, Kose S, Yemenoglu H, Turker Sener L, Kuluslu G. Influences of periodontitis on hippocampal inflammation, oxidative stress, and apoptosis in rats. J Periodontal Res 2021; 56:1154-1162. [PMID: 34486732 DOI: 10.1111/jre.12929] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 08/26/2021] [Indexed: 12/20/2022]
Abstract
BACKGROUND AND AIM The hippocampus, which has a central role in cognitive and behavioral activities, is one of the most sensitive parts of the brain to systemic inflammatory diseases. This animal study aims to comprehensively investigate the possible inflammatory, oxidative, and apoptotic effects of periodontitis on the hippocampus. METHODS Sixteen male Sprague-Dawley rats were randomly assigned to two groups: control and experimental periodontitis (Ep). In the Ep group, periodontitis was induced by placing 3.0 sutures sub-paramarginally around the necks of right and left mandibular first molars and maintaining the ligatures in place for 5 weeks. Following the euthanasia, mandibula and hippocampus samples were collected bilaterally. Alveolar bone loss was measured histomorphometrically and radiologically on the right and left mandibles. On the right hippocampal sections histological (Caspase-3, TNF-α, and 8-OHdG) and the left hippocampal sections, biochemical (IL-1β, Aβ1-42 , MDA, GSH, and TAS levels) evaluations were performed. RESULTS Histopathological changes associated with periodontitis were limited (p > .05). A slight increase in caspase-3 positive neuron density in EP rats showed that apoptotic changes were also limited (p > .05). 8-OHdG activity, on the other hand, was significantly higher compared to controls (p < .05). In biochemical analysis, there was a significant increase in IL-1β levels and oxidative membrane damage (MDA) (p < .05) whereas Aβ1-42 and antioxidant marker (GSH and TAS) levels were slightly increased (p > .05). CONCLUSION Periodontitis causes marked increases in IL-1β levels and oxidative stress in the hippocampus, but limited degenerative and apoptotic changes.
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Affiliation(s)
- Oğuz Kose
- Department of Periodontology, School of Dentistry, Recep Tayyip Erdogan University, Rize, Turkey
| | - Ahmet Altin
- Department of Periodontology, School of Dentistry, Recep Tayyip Erdogan University, Rize, Turkey
| | - Sevda Kurt Bayrakdar
- Department of Periodontology, School of Dentistry, Eskişehir Osmangazi University, Eskisehir, Turkey
| | - Semih Alperen Bostan
- Department of Periodontology, School of Dentistry, Recep Tayyip Erdogan University, Rize, Turkey
| | - Tolga Mercantepe
- Department of Histology and Embryology, School of Medicine, Recep Tayyip Erdogan University, Rize, Turkey
| | - Kerimali Akyildiz
- Department of Medical Services and Techniques, School of Health Care Services Vocational, Recep Tayyip Erdogan University, Rize, Turkey
| | - Levent Tumkaya
- Department of Histology and Embryology, School of Medicine, Recep Tayyip Erdogan University, Rize, Turkey
| | - Adnan Yilmaz
- Department of Biochemistry, School of Medicine, Recep Tayyip Erdogan University, Rize, Turkey
| | - Sefanur Kose
- Department of Psychiatry, School of Medicine, Recep Tayyip Erdogan University, Rize, Turkey
| | - Hatice Yemenoglu
- Department of Periodontology, School of Dentistry, Recep Tayyip Erdogan University, Rize, Turkey
| | - Leyla Turker Sener
- Department of Biophysics, School of Medicine, Istanbul University, Istanbul, Turkey
| | - Göker Kuluslu
- 3D Medical and Industrial Design Laboratory, Istanbul University, Istanbul, Turkey
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Ryder MI, Xenoudi P. Alzheimer disease and the periodontal patient: New insights, connections, and therapies. Periodontol 2000 2021; 87:32-42. [PMID: 34463981 DOI: 10.1111/prd.12389] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Loss of cognitive function in the aging population, particular those with Alzheimer disease, presents unique challenges to health practitioners. For the dental practitioner these include management of periodontal diseases, caries, and other dental conditions in this special population. It is well established in the cognitively impaired patient that a lack of adherence to dental hygiene routines and professional care leads to increases in the prevalence and severity of these dental conditions, leading to increased loss of teeth. More recent evidence has indicated a possible role of the microbiota of dental plaque associated with periodontal diseases in the development and progression of Alzheimer disease, thereby supporting a two-way interaction of these two diseases. New therapies are needed to address the potential upstream events that may precede overt signs of Alzheimer disease. One of these approaches would be to target these various bacterial, viral, and other microbial pathogens associated with periodontal disease that can translocate into the bloodstream and then to distal sites, such as the brain. Such microbial translocation would lead to local inflammation and buildup of the hallmark signs of Alzheimer disease, including amyloid beta deposits, tau fragmentation and tangles, breakdown of host protective molecules, such as the apolipoproteins, and neuron toxicity. In this review, evidence for the biological basis of the role of the periodontal disease microflora on the initiation and progression of Alzheimer disease will be presented with a focus on the potential role of the keystone pathogen Porphyromonas gingivalis with its family of gingipain enzymes. The various mechanisms for which P. gingivalis gingipains may contribute to the initiation and progression of Alzheimer disease are presented. Small-molecule inhibitors of these gingipains and their effects on reducing biological markers of Alzheimer disease may have beneficial effects for the initiation and progression of loss of cognitive function in Alzheimer disease. In addition to these targeted therapies for specific periodontal pathogens, considerations for the dental practitioner in applying more general approaches to reducing the periodontal plaque microflora in the management of the cognitively impaired patient are discussed for this special population.
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Affiliation(s)
- Mark I Ryder
- Division of Periodontology, Department of Orofacial Sciences, School of Dentistry, University of California, San Francisco, California, USA
| | - Pinelopi Xenoudi
- College of Dental Medicine, California Northstate University, Elk Grove, California, USA
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Mathis SP, Bodduluri SR, Haribabu B. Interrelationship between the 5-lipoxygenase pathway and microbial dysbiosis in the progression of Alzheimer's disease. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:158982. [PMID: 34062254 DOI: 10.1016/j.bbalip.2021.158982] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 05/11/2021] [Accepted: 05/17/2021] [Indexed: 02/08/2023]
Abstract
Alzheimer's disease (AD) is an age-related neurodegenerative disorder involving neurofibrillary tangles and amyloid plaques. The tau phosphorylation responsible for neurofibrillary tangles and amyloid deposition which causes plaques are both accelerated through the activity of 5-lipoxygenase (5-LO). In addition to these pathological pathways, 5-LO has also been linked to the neuro-inflammation associated with disease progression as well as to dysbiosis in the gut. Interestingly, gut dysbiosis itself has been correlated to AD development. Not only do gut metabolites have direct effects on the brain, but pro-inflammatory mediators such as LPS, BMAA and bacterial amyloids produced in the gut due to dysbiosis reach the brain causing increased neuro-inflammation. While microbial dysbiosis and 5-LO exert detrimental effects in the brain, the cause/effect relationship between these factors remain unknown. These issues may be addressed using mouse models of AD in the context of different knockout mice in the 5-LO pathway in specific pathogen-free, germ-free as well as gnotobiotic conditions.
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Affiliation(s)
- Steven P Mathis
- Department of Microbiology and Immunology, James Graham Brown Cancer Center and Center for Microbiomics, Inflammation and Pathogenicity, Louisville, KY 40202, United States of America; University of Louisville Health Sciences Center, Louisville, KY 40202, United States of America
| | - Sobha R Bodduluri
- Department of Microbiology and Immunology, James Graham Brown Cancer Center and Center for Microbiomics, Inflammation and Pathogenicity, Louisville, KY 40202, United States of America; University of Louisville Health Sciences Center, Louisville, KY 40202, United States of America
| | - Bodduluri Haribabu
- Department of Microbiology and Immunology, James Graham Brown Cancer Center and Center for Microbiomics, Inflammation and Pathogenicity, Louisville, KY 40202, United States of America; University of Louisville Health Sciences Center, Louisville, KY 40202, United States of America.
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54
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Hu X, Zhang J, Qiu Y, Liu Z. Periodontal disease and the risk of Alzheimer's disease and mild cognitive impairment: a systematic review and meta-analysis. Psychogeriatrics 2021; 21:813-825. [PMID: 34247432 DOI: 10.1111/psyg.12743] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 06/08/2021] [Accepted: 06/24/2021] [Indexed: 12/12/2022]
Abstract
BACKGROUND Results of studies on the association between periodontal disease (PD) and Alzheimer's disease (AD) or mild cognitive impairment (MCI) are inconsistent, and a previous meta-analysis published in 2017 included inadequate studies and is thus outmoded. This study aims to systematically evaluate the correlation between PD and the risk of AD or MCI. METHODS The following electronic databases were screened by two investigators independently, without restriction of language: CENTRAL (Cochrane library), PubMed (MEDLINE), EMBASE, China National Knowledge Interne, China Science and Technology Journal Database, Wanfang Data, www.ClinicalTrials.gov, and WHO International Clinical Trials Registry Platform. Meta-analysis was conducted using random-effects model or fixed-effects model according to the heterogeneity of included studies. RESULTS Thirteen eligible studies, of which eight reported AD (291 114 participants) and eight reported MCI (4805 participants), were included in this meta-analysis. The pooled results showed that compared with the non-PD population, the risk of AD and MCI in PD patients was significantly higher (for AD: odds ratio (OR) = 1.78, 95% CI 1.15-2.76; for MCI: OR = 1.60, 95% CI 1.24-2.06), and especially in those with severe PD (for AD: OR = 4.89, 95% CI 1.60-14.97; for MCI, OR = 2.32, 95% CI 1.24-4.36). CONCLUSIONS This meta-analysis indicated that PD was related to an elevated risk of AD and cognitive impairment, and that it should receive early intervention.
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Affiliation(s)
- Xin Hu
- School of Public Health, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Jing Zhang
- School of Public Health, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Yulan Qiu
- School of Public Health, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Zhaonan Liu
- School of Medicine, Shanghai Renji Hospital, Shanghai Jiao Tong University, Shanghai, China
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Bregaint S, Boyer E, Fong SB, Meuric V, Bonnaure-Mallet M, Jolivet-Gougeon A. Porphyromonas gingivalis outside the oral cavity. Odontology 2021; 110:1-19. [PMID: 34410562 DOI: 10.1007/s10266-021-00647-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 07/31/2021] [Indexed: 12/14/2022]
Abstract
Porphyromonas gingivalis, a Gram-negative anaerobic bacillus present in periodontal disease, is considered one of the major pathogens in periodontitis. A literature search for English original studies, case series and review articles published up to December 2019 was performed using the MEDLINE, PubMed and GoogleScholar databases, with the search terms "Porphyromonas gingivalis" AND the potentially associated condition or systemic disease Abstracts and full text articles were used to make a review of published research literature on P. gingivalis outside the oral cavity. The main points of interest of this narrative review were: (i) a potential direct action of the bacterium and not the systemic effects of the inflammatory acute-phase response induced by the periodontitis, (ii) the presence of the bacterium (viable or not) in the organ, or (iii) the presence of its virulence factors. Virulence factors (gingipains, capsule, fimbriae, hemagglutinins, lipopolysaccharide, hemolysin, iron uptake transporters, toxic outer membrane blebs/vesicles, and DNA) associated with P. gingivalis can deregulate certain functions in humans, particularly host immune systems, and cause various local and systemic pathologies. The most recent studies linking P. gingivalis to systemic diseases were discussed, remembering particularly the molecular mechanisms involved in different infections, including cerebral, cardiovascular, pulmonary, bone, digestive and peri-natal infections. Recent involvement of P. gingivalis in neurological diseases has been demonstrated. P. gingivalis modulates cellular homeostasis and increases markers of inflammation. It is also a factor in the oxidative stress involved in beta-amyloid production.
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Affiliation(s)
- Steeve Bregaint
- Microbiology, INSERM, INRAE, CHU Rennes, Institut NUMECAN (Nutrition Metabolisms and Cancer), Université de Rennes, U1241, 2, avenue du Professeur Léon Bernard, 35043, Rennes, France
| | - Emile Boyer
- Microbiology, INSERM, INRAE, CHU Rennes, Institut NUMECAN (Nutrition Metabolisms and Cancer), Université de Rennes, U1241, 2, avenue du Professeur Léon Bernard, 35043, Rennes, France.,Teaching Hospital Pontchaillou, 2 rue Henri Le Guilloux, 35033, Rennes, France
| | - Shao Bing Fong
- Microbiology, INSERM, INRAE, CHU Rennes, Institut NUMECAN (Nutrition Metabolisms and Cancer), Université de Rennes, U1241, 2, avenue du Professeur Léon Bernard, 35043, Rennes, France
| | - Vincent Meuric
- Microbiology, INSERM, INRAE, CHU Rennes, Institut NUMECAN (Nutrition Metabolisms and Cancer), Université de Rennes, U1241, 2, avenue du Professeur Léon Bernard, 35043, Rennes, France.,Teaching Hospital Pontchaillou, 2 rue Henri Le Guilloux, 35033, Rennes, France
| | - Martine Bonnaure-Mallet
- Microbiology, INSERM, INRAE, CHU Rennes, Institut NUMECAN (Nutrition Metabolisms and Cancer), Université de Rennes, U1241, 2, avenue du Professeur Léon Bernard, 35043, Rennes, France.,Teaching Hospital Pontchaillou, 2 rue Henri Le Guilloux, 35033, Rennes, France
| | - Anne Jolivet-Gougeon
- Microbiology, INSERM, INRAE, CHU Rennes, Institut NUMECAN (Nutrition Metabolisms and Cancer), Université de Rennes, U1241, 2, avenue du Professeur Léon Bernard, 35043, Rennes, France. .,Teaching Hospital Pontchaillou, 2 rue Henri Le Guilloux, 35033, Rennes, France.
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Yoshida K, Yoshida K, Fujiwara N, Seyama M, Ono K, Kawai H, Guo J, Wang Z, Weng Y, Yu Y, Uchida-Fukuhara Y, Ikegame M, Sasaki A, Nagatsuka H, Kamioka H, Okamura H, Ozaki K. Extracellular vesicles of P. gingivalis-infected macrophages induce lung injury. Biochim Biophys Acta Mol Basis Dis 2021; 1867:166236. [PMID: 34389473 DOI: 10.1016/j.bbadis.2021.166236] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/19/2021] [Accepted: 07/27/2021] [Indexed: 02/08/2023]
Abstract
Periodontal diseases are common inflammatory diseases that are induced by infection with periodontal bacteria such as Porphyromonas gingivalis (Pg). The association between periodontal diseases and many types of systemic diseases has been demonstrated; the term "periodontal medicine" is used to describe how periodontal infection/inflammation may impact extraoral health. However, the molecular mechanisms by which the factors produced in the oral cavity reach multiple distant organs and impact general health have not been elucidated. Extracellular vesicles (EVs) are nano-sized spherical structures secreted by various types of cells into the tissue microenvironment, and influence pathophysiological conditions by delivering their cargo. However, a detailed understanding of the effect of EVs on periodontal medicine is lacking. In this study, we investigated whether EVs derived from Pg-infected macrophages reach distant organs in mice and influence the pathophysiological status. EVs were isolated from human macrophages, THP-1 cells, infected with Pg. We observed that EVs from Pg-infected THP-1 cells (Pg-inf EVs) contained abundant core histone proteins such as histone H3 and translocated to the lungs, liver, and kidneys of mice. Pg-inf EVs also induced pulmonary injury, including edema, vascular congestion, inflammation, and collagen deposition causing alveoli destruction. The Pg-inf EVs or the recombinant histone H3 activated the NF-κB pathway, leading to increase in the levels of pro-inflammatory cytokines in human lung epithelial A549 cells. Our results suggest a possible mechanism by which EVs produced in periodontal diseases contribute to the progression of periodontal medicine.
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Affiliation(s)
- Kayo Yoshida
- Department of Oral Healthcare Promotion, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Kaya Yoshida
- Department of Oral Healthcare Education, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan.
| | - Natsumi Fujiwara
- Department of Oral Healthcare Promotion, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Mariko Seyama
- Department of Oral Healthcare Promotion, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Kisho Ono
- Department of Oral and Maxillofacial Surgery and Biopathology, Graduate School of Medicine, Okayama, Japan
| | - Hotaka Kawai
- Department of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Jiajie Guo
- School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral Diseases, Shenyang, China; Department of Oral Morphology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Ziyi Wang
- Department of Orthodontics, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Yao Weng
- Department of Oral Morphology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Yaqiong Yu
- School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral Diseases, Shenyang, China; Department of Oral Morphology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Yoko Uchida-Fukuhara
- Department of Oral Morphology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Mika Ikegame
- Department of Oral Morphology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Akira Sasaki
- Department of Oral and Maxillofacial Surgery and Biopathology, Graduate School of Medicine, Okayama, Japan
| | - Hitoshi Nagatsuka
- Department of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Hiroshi Kamioka
- Department of Orthodontics, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Hirohiko Okamura
- Department of Oral Morphology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Kazumi Ozaki
- Department of Oral Healthcare Promotion, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
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Lotz SK, Blackhurst BM, Reagin KL, Funk KE. Microbial Infections Are a Risk Factor for Neurodegenerative Diseases. Front Cell Neurosci 2021; 15:691136. [PMID: 34305533 PMCID: PMC8292681 DOI: 10.3389/fncel.2021.691136] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 06/08/2021] [Indexed: 12/13/2022] Open
Abstract
Neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis, comprise a family of disorders characterized by progressive loss of nervous system function. Neuroinflammation is increasingly recognized to be associated with many neurodegenerative diseases but whether it is a cause or consequence of the disease process is unclear. Of growing interest is the role of microbial infections in inciting degenerative neuroinflammatory responses and genetic factors that may regulate those responses. Microbial infections cause inflammation within the central nervous system through activation of brain-resident immune cells and infiltration of peripheral immune cells. These responses are necessary to protect the brain from lethal infections but may also induce neuropathological changes that lead to neurodegeneration. This review discusses the molecular and cellular mechanisms through which microbial infections may increase susceptibility to neurodegenerative diseases. Elucidating these mechanisms is critical for developing targeted therapeutic approaches that prevent the onset and slow the progression of neurodegenerative diseases.
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Affiliation(s)
| | | | | | - Kristen E. Funk
- Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, NC, United States
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58
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Sharma VK, Singh TG, Garg N, Dhiman S, Gupta S, Rahman MH, Najda A, Walasek-Janusz M, Kamel M, Albadrani GM, Akhtar MF, Saleem A, Altyar AE, Abdel-Daim MM. Dysbiosis and Alzheimer's Disease: A Role for Chronic Stress? Biomolecules 2021; 11:biom11050678. [PMID: 33946488 PMCID: PMC8147174 DOI: 10.3390/biom11050678] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 04/23/2021] [Accepted: 04/26/2021] [Indexed: 02/06/2023] Open
Abstract
Alzheimer’s disease (AD) is an incurable, neuropsychiatric, pathological condition that deteriorates the worth of geriatric lives. AD is characterized by aggregated senile amyloid plaques, neurofibrillary tangles, neuronal loss, gliosis, oxidative stress, neurotransmitter dysfunction, and bioenergetic deficits. The changes in GIT composition and harmony have been recognized as a decisive and interesting player in neuronal pathologies including AD. Microbiota control and influence the oxidoreductase status, inflammation, immune system, and the endocrine system through which it may have an impact on the cognitive domain. The altered and malfunctioned state of microbiota is associated with minor infections to complicated illnesses that include psychosis and neurodegeneration, and several studies show that microbiota regulates neuronal plasticity and neuronal development. The altered state of microbiota (dysbiosis) may affect behavior, stress response, and cognitive functions. Chronic stress-mediated pathological progression also has a well-defined role that intermingles at various physiological levels and directly impacts the pathological advancement of AD. Chronic stress-modulated alterations affect the well-established pathological markers of AD but also affect the gut–brain axis through the mediation of various downstream signaling mechanisms that modulate the microbial commensals of GIT. The extensive literature reports that chronic stressors affect the composition, metabolic activities, and physiological role of microbiota in various capacities. The present manuscript aims to elucidate mechanistic pathways through which stress induces dysbiosis, which in turn escalates the neuropathological cascade of AD. The stress–dysbiosis axis appears a feasible zone of work in the direction of treatment of AD.
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Affiliation(s)
- Vivek Kumar Sharma
- Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India; (V.K.S.); (N.G.); (S.D.); (S.G.)
- Goverment College of Pharmacy, District Shimla, Rohru 171207, India
| | - Thakur Gurjeet Singh
- Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India; (V.K.S.); (N.G.); (S.D.); (S.G.)
- Correspondence: or (T.G.S.); (M.M.A.-D.); Tel.: +91-98-1595-1171 (T.G.S.); +20-96-65-8019-2142 (M.M.A.-D.)
| | - Nikhil Garg
- Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India; (V.K.S.); (N.G.); (S.D.); (S.G.)
| | - Sonia Dhiman
- Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India; (V.K.S.); (N.G.); (S.D.); (S.G.)
| | - Saurabh Gupta
- Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India; (V.K.S.); (N.G.); (S.D.); (S.G.)
| | - Md. Habibur Rahman
- Department of Pharmacy, Southeast University, Banani, Dhaka 1213, Bangladesh;
| | - Agnieszka Najda
- Laboratory of Quality of Vegetables and Medicinal Plants, Department of Vegetable Crops and Medicinal Plants, University of Life Sciences in Lublin, 15 Akademicka Street, 20-950 Lublin, Poland; (A.N.); (M.W.-J.)
| | - Magdalena Walasek-Janusz
- Laboratory of Quality of Vegetables and Medicinal Plants, Department of Vegetable Crops and Medicinal Plants, University of Life Sciences in Lublin, 15 Akademicka Street, 20-950 Lublin, Poland; (A.N.); (M.W.-J.)
| | - Mohamed Kamel
- Department of Medicine and Infectious Diseases, Faculty of Veterinary Medicine, Cairo University, Giza 12211, Egypt;
| | - Ghadeer M. Albadrani
- Department of Biology, College of Science, Princess Nourah bint Abdulrahman University, Riyadh 11474, Saudi Arabia;
| | - Muhammad Furqan Akhtar
- Riphah Institute of Pharmaceutical Sciences, Riphah International University, Lahore Campus, Lahore 54950, Pakistan;
| | - Ammara Saleem
- Department of Pharmacology, Faculty of Pharmaceutical Sciences, Government College University Faisalabad, Faisalabad 38000, Pakistan;
| | - Ahmed E. Altyar
- Department of Pharmacy Practice, Faculty of Pharmacy, King Abdulaziz University, P.O. Box 80260, Jeddah 21589, Saudi Arabia;
| | - Mohamed M. Abdel-Daim
- Pharmacology Department, Faculty of Veterinary Medicine, Suez Canal University, Ismailia 41522, Egypt
- Correspondence: or (T.G.S.); (M.M.A.-D.); Tel.: +91-98-1595-1171 (T.G.S.); +20-96-65-8019-2142 (M.M.A.-D.)
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Astuti SD, Utomo IB, Setiawatie EM, Khasanah M, Purnobasuki H, Arifianto D, Alamsyah KA. Combination effect of laser diode for photodynamic therapy with doxycycline on a wistar rat model of periodontitis. BMC Oral Health 2021; 21:80. [PMID: 33607998 PMCID: PMC7893773 DOI: 10.1186/s12903-021-01435-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 02/09/2021] [Indexed: 11/16/2022] Open
Abstract
Background Periodontitis is a chronic inflammatory disease characterized by progressive damage on the structure of tooth-supporting tissues. The aim of the study is determining the combination photodynamic effect of diode laser 405 nm treatments and the administration of doxycycline 0.1% within 1, 3, 5, and 7 days on a Wistar rat model of periodontitis. Methods Samples were induced with Porphyromonas gingivalis ATCC33277 to allow periodontitis development and were treated with combination of doxycycline and laser diode, then statistical analysis was carried out (One-Way ANOVA test and the post-hoc Duncan test; Kruskal–Wallis test and Mann–Whitney follow-up test for non-parametric data). Samples were divided into five groups, laser exposure used was 405-nm diode laser with energy density of 8 J/cm2. The expression level of histomorphometric was calculated by measuring the number of macrophages, lymphocytes, fibroblasts and the distance between the CEJ-AV. Results The results showed that the combination treatment of doxycycline and laser exposure yielded immunomodulatory effects. The expression level of fibroblast and the distance between CEJ-AV bone showed that the combination of doxycycline and laser therapy exerted healing effect in rat models of periodontitis on day 5 and 7. Conclusion The combination of doxycycline 0.1% and diode laser therapy provides a healing effect in rats models of periodontitis.
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Affiliation(s)
- Suryani Dyah Astuti
- Department of Physics, Faculty of Science and Technology, Universitas Airlangga, Mulyorejo Street, Campus C Universitas Airlangga, Surabaya, 60115, Indonesia. .,Biomedical Engineering Master Program, Faculty of Science and Technology, Universitas Airlangga, Surabaya, 60115, Indonesia. .,Biophysics and Medical Physics Research Group, Faculty of Sciences and Technology, Universitas Airlangga, Surabaya, 60115, Indonesia.
| | - Irawan Budi Utomo
- Biomedical Engineering Master Program, Faculty of Science and Technology, Universitas Airlangga, Surabaya, 60115, Indonesia
| | | | - Miratul Khasanah
- Department of Chemistry, Faculty of Science and Technology, Universitas Airlangga, Surabaya, 60115, Indonesia
| | - Hery Purnobasuki
- Department of Biology, Faculty of Science and Technology, Universitas Airlangga, Surabaya, 60115, Indonesia
| | - Deny Arifianto
- Faculty of Voccasional, Universitas Airlangga, Surabaya, 60115, Indonesia
| | - Kartika Anggraini Alamsyah
- Biomedical Engineering Master Program, Faculty of Science and Technology, Universitas Airlangga, Surabaya, 60115, Indonesia
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Relationship of Porphyromonas gingivalis and Alzheimer's disease: a systematic review of pre-clinical studies. Clin Oral Investig 2021; 25:797-806. [PMID: 33469718 DOI: 10.1007/s00784-020-03764-w] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 12/21/2020] [Indexed: 12/13/2022]
Abstract
OBJECTIVES This study aimed to analyze the following PICO question: Are animals infected with Porphyromonas gingivalis (P. gingivalis) or bacterial lipopolysaccharide (Pg-LPS) more affected by neurodegeneration, similar to the pathogenesis generated by Alzheimer's disease (AD), compared with non-infected animals? METHODS Databases PubMed, Lilacs, SciELO, Science Direct, Scopus, Web of Science, and Cochrane were searched for pre-clinical in vivo studies in which mice were infected with P. gingivalis or received Pg-LPS, in order to assess the brain tissue and cognitive impairment. No limit for date or publication language was imposed and this study was registered at the International Prospective Register of Systematic Reviews (PROSPERO), with nine articles included. Syrcle's protocol was used to evaluate bias in the selected studies. RESULTS Nine articles were included. Infection by P. gingivalis or the administration of Pg-LPS increased the production of the inflammatory mediators, TNF-α (tumor necrosis factor-alpha), IL-6 (interleukin-6), and IL-1β (interleukin-1beta), augmented Aβ (amyloid beta) production, and activated the complement system, causing inflammation, brain tissue degeneration, and cognitive impairment, consistent with the damage in AD. CONCLUSIONS Infection by P. gingivalis and Pg-LPS administration appears to be in relation with the pathogenesis of AD by activating the complement cascade, increasing Aβ production and augmenting pro-inflammatory cytokine expression, causing age-dependent brain inflammation, neuroinflammation, and neurodegeneration. CLINICAL RELEVANCE Taking into account the importance of holistic treatment in the dental office, this study focuses on identifying highly prevalent oral diseases, such as periodontal disease, as risk factors for the aggravation of degenerative diseases in the elderly population.
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Qian X, Zhang S, Duan L, Yang F, Zhang K, Yan F, Ge S. Periodontitis Deteriorates Cognitive Function and Impairs Neurons and Glia in a Mouse Model of Alzheimer's Disease. J Alzheimers Dis 2021; 79:1785-1800. [PMID: 33459718 DOI: 10.3233/jad-201007] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND Although periodontitis is reportedly associated with increased cognitive decline in Alzheimer's disease, the mechanisms underlying this process remain unknown. Porphyromonas gingivalis lipopolysaccharide (P.g-LPS) is an endotoxin associated with periodontal disease. OBJECTIVE We investigated the effect of periodontitis on learning capacity and memory of amyloid-β protein precursor (AβPP)/presenilin (PS1) transgenic mice along with the mechanisms underlying these effects. METHODS Mice were randomly assigned to three groups, namely AβPP/PS1 (control), P.g-LPS Injection, and P.g-LPS Injection + Ligation. Mice from the P.g-LPS Injection group were injected with P.g-LPS in the periodontal tissue three times per week for 8 weeks, while mice from the P.g-LPS Injection + Ligation group were injected with P.g-LPS and subjected to ligation of the gingival sulcus of the maxillary second molar. RESULTS Expression of gingival proinflammatory cytokines as well as alveolar bone resorption in P.g-LPS-injected and ligatured mice was increased compared to that in control mice. Mice in the P.g-LPS Injection + Ligation group exhibited cognitive impairment and a significant reduction in the number of neurons. Glial cell activation in the experimental groups with significantly increased amyloid-β (Aβ) levels was more pronounced relative to the control group. Induction of periodontitis was concurrent with an increase in cyclooxygenase-2, inducible nitric oxide synthase, AβPP, and beta-secretase 1 expression and a decrease in A disintegrin and metalloproteinase domain-containing protein 10 expression. CONCLUSION These findings indicated that periodontitis exacerbated learning and memory impairment in AβPP/PS1 mice and augmented Aβ and neuroinflammatory responses. Our study provides a theoretical basis for risk prediction and early intervention of Alzheimer's disease and periodontitis.
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Affiliation(s)
- Xueshen Qian
- Hospital of Stomatology, Zunyi Medical University, Zunyi, Guizhou, China.,Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Shuang Zhang
- Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Lian Duan
- Hospital of Stomatology, Zunyi Medical University, Zunyi, Guizhou, China
| | - Fengchun Yang
- Hospital of Stomatology, Zunyi Medical University, Zunyi, Guizhou, China
| | - Kun Zhang
- Hospital of Stomatology, Zunyi Medical University, Zunyi, Guizhou, China
| | - Fuhua Yan
- Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Song Ge
- Hospital of Stomatology, Zunyi Medical University, Zunyi, Guizhou, China
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Bachtiar EW, Putri CF, Soejoedono RD, Bachtiar BM. Expression of TNF, IL1B, and iNOS2 in the neural cell after induced by Porphyromonas gingivalis with and without coating antibody anti -Porphyromonas gingivalis. F1000Res 2020; 9:1499. [PMID: 34367622 PMCID: PMC8311800 DOI: 10.12688/f1000research.26749.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/24/2021] [Indexed: 11/20/2022] Open
Abstract
Porphyromonas gingivalis has virulence factors such as gingipain and lipopolysaccharide, causing bacteremia to reach the brain and activate neuroinflammatory release cytokines. This study analyzed the effect of the co-culture of neuron cells with P. gingivalis coated with anti -P. gingivalis antibodies against cytokines produced by neuron cells. The gene expressions of the TNF, IL1B, iNOS2 in neurons was evaluated using RT-qPCR. The results showed that P. gingivalis coated with anti -P. gingivalis antibody before co-culture with neuron cells could decrease the gene expression of TNF, IL1B, and iNOS2 of neuron cells.
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Affiliation(s)
- Endang Winiati Bachtiar
- Department of Oral Biology and Oral Science Research Center, Faculty of Dentistry Universitas Indonesia, Jakarta, DKI, 10430, Indonesia
| | - Citra F. Putri
- Department of Oral Biology and Oral Science Research Center, Faculty of Dentistry Universitas Indonesia, Jakarta, DKI, 10430, Indonesia
| | - Retno D. Soejoedono
- Department of Infectious Diseases and Veterinary Public Health, Faculty of Veterinary Medicine, IPB University, Bogor, Indonesia
| | - Boy M. Bachtiar
- Department of Oral Biology and Oral Science Research Center, Faculty of Dentistry Universitas Indonesia, Jakarta, DKI, 10430, Indonesia
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63
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Bachtiar EW, Putri CF, Soejoedono RD, Bachtiar BM. Expression of TNF, IL1B, and iNOS2 in the neural cell after induced by Porphyromonas gingivalis with and without coating antibody anti -Porphyromonas gingivalis. F1000Res 2020; 9:1499. [PMID: 34367622 PMCID: PMC8311800 DOI: 10.12688/f1000research.26749.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/19/2021] [Indexed: 04/04/2024] Open
Abstract
Porphyromonas gingivalis has virulence factors such as gingipain and lipopolysaccharide, causing bacteremia to reach the brain and activate neuroinflammatory release cytokines. This study analyzed the effect of the co-culture of neuron cells with P. gingivalis coated with anti -P. gingivalis antibodies against cytokines produced by neuron cells. The gene expressions of the TNF, IL1B, iNOS2 in neurons was evaluated using RT-qPCR. The results showed that P. gingivalis coated with anti -P. gingivalis antibody before co-culture with neuron cells could decrease the gene expression of TNF, IL1B, and iNOS2 of neuron cells.
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Affiliation(s)
- Endang Winiati Bachtiar
- Department of Oral Biology and Oral Science Research Center, Faculty of Dentistry Universitas Indonesia, Jakarta, DKI, 10430, Indonesia
| | - Citra F. Putri
- Department of Oral Biology and Oral Science Research Center, Faculty of Dentistry Universitas Indonesia, Jakarta, DKI, 10430, Indonesia
| | - Retno D. Soejoedono
- Department of Infectious Diseases and Veterinary Public Health, Faculty of Veterinary Medicine, IPB University, Bogor, Indonesia
| | - Boy M. Bachtiar
- Department of Oral Biology and Oral Science Research Center, Faculty of Dentistry Universitas Indonesia, Jakarta, DKI, 10430, Indonesia
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64
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Bachtiar EW, Putri CF, Soejoedono RD, Bachtiar BM. Expression of TNF, IL1B, and NOS2 in the neural cell after induced by Porphyromonas gingivalis with and without coating antibody anti -Porphyromonas gingivalis. F1000Res 2020; 9:1499. [PMID: 34367622 PMCID: PMC8311800 DOI: 10.12688/f1000research.26749.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/08/2021] [Indexed: 04/04/2024] Open
Abstract
Porphyromonas gingivalis has virulence factors such as gingipain and lipopolysaccharide, causing bacteremia to reach the brain and activate neuroinflammatory release cytokines. This study analyzed the effect of the co-culture of neuron cells with P. gingivalis coated with anti -P. gingivalis antibodies against cytokines produced by neuron cells. The gene expressions of the TNF, IL1B, NOS2 in neurons was evaluated using RT-qPCR. The results showed that P. gingivalis coated with anti -P. gingivalis antibody before co-culture with neuron cells could decrease the gene expression of TNF, IL1B, and NOS2 of neuron cells.
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Affiliation(s)
- Endang Winiati Bachtiar
- Department of Oral Biology and Oral Science Research Center, Faculty of Dentistry Universitas Indonesia, Jakarta, DKI, 10430, Indonesia
| | - Citra F. Putri
- Department of Oral Biology and Oral Science Research Center, Faculty of Dentistry Universitas Indonesia, Jakarta, DKI, 10430, Indonesia
| | - Retno D. Soejoedono
- Department of Infectious Diseases and Veterinary Public Health, Faculty of Veterinary Medicine, IPB University, Bogor, Indonesia
| | - Boy M. Bachtiar
- Department of Oral Biology and Oral Science Research Center, Faculty of Dentistry Universitas Indonesia, Jakarta, DKI, 10430, Indonesia
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65
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Bachtiar EW, Putri CF, Soejoedono RD, Bachtiar BM. Expression of TNF, IL1B, and NOS2 in the neural cell after induced by Porphyromonas gingivalis with and without coating antibody anti -Porphyromonas gingivalis. F1000Res 2020; 9:1499. [PMID: 34367622 PMCID: PMC8311800 DOI: 10.12688/f1000research.26749.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/17/2020] [Indexed: 04/04/2024] Open
Abstract
Porphyromonas gingivalis has virulence factors such as gingipain and lipopolysaccharide, causing bacteremia to reach the brain and activate neuroinflammatory release cytokines. This study analyzed the effect of the co-culture of neuron cells with P. gingivalis coated with anti -P. gingivalis antibodies against cytokines produced by neuron cells. The gene expressions of the TNF, IL1B, NOS2 in neurons was evaluated using RT-qPCR. The results showed that P. gingivalis coated with anti -P. gingivalis antibody before co-culture with neuron cells could decrease the gene expression of TNF, IL1B, and NOS2 of neuron cells.
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Affiliation(s)
- Endang Winiati Bachtiar
- Department of Oral Biology and Oral Science Research Center, Faculty of Dentistry Universitas Indonesia, Jakarta, DKI, 10430, Indonesia
| | - Citra F. Putri
- Department of Oral Biology and Oral Science Research Center, Faculty of Dentistry Universitas Indonesia, Jakarta, DKI, 10430, Indonesia
| | - Retno D. Soejoedono
- Department of Infectious Diseases and Veterinary Public Health, Faculty of Veterinary Medicine, IPB University, Bogor, Indonesia
| | - Boy M. Bachtiar
- Department of Oral Biology and Oral Science Research Center, Faculty of Dentistry Universitas Indonesia, Jakarta, DKI, 10430, Indonesia
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Kanagasingam S, Chukkapalli SS, Welbury R, Singhrao SK. Porphyromonas gingivalis is a Strong Risk Factor for Alzheimer's Disease. J Alzheimers Dis Rep 2020; 4:501-511. [PMID: 33532698 PMCID: PMC7835991 DOI: 10.3233/adr-200250] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Porphyromonas gingivalis (P. gingivalis) is one of the several important bacterial pathogens associated with the sporadic Alzheimer’s disease (AD). Different serotypes are either capsulated or are non-capsulated. It has been demonstrated that P. gingivalis (non-capsulated) can reproduce the neurodegenerative AD-like changes in vitro, and a capsular P. gingivalis (strain W83) could reproduce the cardinal hallmark lesions of AD in a wild-type mouse model. All P. gingivalis forms express proteolytically active proteases that enable cleavage of the amyloid-β protin precursor (AβPP) and tau resulting in the formation of amyloid-β and neurofibrillary tangles. Tau is an established substrate for gingipains, which can cleave tau into various peptides. Some of the P. gingivalis fragmented tau protein peptides contain “VQIINK” and “VQIVYK” hexapeptide motifs which map to the flanking regions of the microtubule binding domains and are also found in paired helical filaments that form NFTs. P. gingivalis can induce peripheral inflammation in periodontitis and can also initiate signaling pathways that activate kinases, which in turn, phosphorylate neuronal tau. Periodontal disease related inflammation has metabolic implications for an individual’s peripheral and brain health as patients suffering from generalized periodontitis often have related co-morbidities and are “at risk” of developing AD. The aim here is to discuss the role of P. gingivalis behind such associations with the backdrop of huge efforts to test P. gingivalis virulence factors clinically (GAIN Trial: Phase 2/3 Study of COR388 in Subjects with AD) with inhibitors, which may lead to an intervention by reducing the pathogenic bacterial load.
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Affiliation(s)
- Shalini Kanagasingam
- Brain and Behavior Centre, Faculty of Clinical and Biomedical Sciences, School of Dentistry, University of Central Lancashire, Preston, UK
| | - Sasanka S Chukkapalli
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL, USA
| | - Richard Welbury
- Brain and Behavior Centre, Faculty of Clinical and Biomedical Sciences, School of Dentistry, University of Central Lancashire, Preston, UK
| | - Sim K Singhrao
- Brain and Behavior Centre, Faculty of Clinical and Biomedical Sciences, School of Dentistry, University of Central Lancashire, Preston, UK
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67
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Arjunan P. Eye on the Enigmatic Link: Dysbiotic Oral Pathogens in Ocular Diseases; The Flip Side. Int Rev Immunol 2020; 40:409-432. [PMID: 33179994 DOI: 10.1080/08830185.2020.1845330] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Mouth and associated structures were regarded as separate entities from the rest of the body. However, there is a paradigm shift in this conception and oral health is now considered as a fundamental part of overall well-being. In recent years, the subject of oral-foci of infection has attained a resurgence in terms of systemic morbidities while limited observations denote the implication of chronic oral inflammation in the pathogenesis of eye diseases. Hitherto, there is a paucity for mechanistic insights underlying the reported link between periodontal disease (PD) and ocular comorbidities. In light of prevailing scientific evidence, this review article will focus on the understudied theme, that is, the impact of oral dysbiosis in the induction and/or progression of inflammatory eye diseases like diabetic retinopathy, scleritis, uveitis, glaucoma, age-related macular degeneration (AMD). Furthermore, the plausible mechanisms by which periodontal microbiota may trigger immune dysfunction in the Oro-optic-network and promote the development of PD-associated AMD have been discussed.
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Affiliation(s)
- Pachiappan Arjunan
- Department of Periodontics, Dental College of Georgia, Augusta, GA, USA.,James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA
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68
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Díaz-Zúñiga J, More J, Melgar-Rodríguez S, Jiménez-Unión M, Villalobos-Orchard F, Muñoz-Manríquez C, Monasterio G, Valdés JL, Vernal R, Paula-Lima A. Alzheimer's Disease-Like Pathology Triggered by Porphyromonas gingivalis in Wild Type Rats Is Serotype Dependent. Front Immunol 2020; 11:588036. [PMID: 33240277 PMCID: PMC7680957 DOI: 10.3389/fimmu.2020.588036] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 10/14/2020] [Indexed: 01/18/2023] Open
Abstract
Periodontal disease is a disease of tooth-supporting tissues. It is a chronic disease with inflammatory nature and infectious etiology produced by a dysbiotic subgingival microbiota that colonizes the gingivodental sulcus. Among several periodontal bacteria, Porphyromonas gingivalis (P. gingivalis) highlights as a keystone pathogen. Previous reports have implied that chronic inflammatory response and measurable bone resorption are observed in young mice, even after a short period of periodontal infection with P. gingivalis, which has been considered as a suitable model of experimental periodontitis. Also, encapsulated P. gingivalis strains are more virulent than capsular-defective mutants, causing an increased immune response, augmented osteoclastic activity, and accrued alveolar bone resorption in these rodent experimental models of periodontitis. Recently, P. gingivalis has been associated with Alzheimer’s disease (AD) pathogenesis, either by worsening brain pathology in AD-transgenic mice or by inducing memory impairment and age-dependent neuroinflammation middle-aged wild type animals. We hypothesized here that the more virulent encapsulated P. gingivalis strains could trigger the appearance of brain AD-markers, neuroinflammation, and cognitive decline even in young rats subjected to a short periodontal infection exposure, due to their higher capacity of activating brain inflammatory responses. To test this hypothesis, we periodontally inoculated 4-week-old male Sprague-Dawley rats with K1, K2, or K4 P. gingivalis serotypes and the K1-isogenic non-encapsulated mutant (GPA), used as a control. 45-days after periodontal inoculations with P. gingivalis serotypes, rat´s spatial memory was evaluated for six consecutive days in the Oasis maze task. Following functional testing, the animals were sacrificed, and various tissues were removed to analyze alveolar bone resorption, cytokine production, and detect AD-specific biomarkers. Strikingly, only K1 or K2 P. gingivalis-infected rats displayed memory deficits, increased alveolar bone resorption, pro-inflammatory cytokine production, changes in astrocytic morphology, increased Aβ1-42 levels, and Tau hyperphosphorylation in the hippocampus. None of these effects were observed in rats infected with the non-encapsulated bacterial strains. Based on these results, we propose that the bacterial virulence factors constituted by capsular polysaccharides play a central role in activating innate immunity and inflammation in the AD-like pathology triggered by P. gingivalis in young rats subjected to an acute experimental infection episode.
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Affiliation(s)
- Jaime Díaz-Zúñiga
- Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago, Chile
| | - Jamileth More
- Centro de Investigación Clínica Avanzada (CICA), Hospital Clínico Universidad de Chile, Santiago, Chile
| | | | - Matías Jiménez-Unión
- Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago, Chile
| | | | | | - Gustavo Monasterio
- Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago, Chile
| | - José Luis Valdés
- Biomedical Neuroscience Institute, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,Department of Neuroscience, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Rolando Vernal
- Periodontal Biology Laboratory, Faculty of Dentistry, Universidad de Chile, Santiago, Chile
| | - Andrea Paula-Lima
- Biomedical Neuroscience Institute, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,Department of Neuroscience, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,Faculty of Dentistry, Institute for Research in Dental Sciences, Universidad de Chile, Santiago, Chile
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Tsukahara T, Toyoda A, Kawase T, Nakamura SI, Ochiai K. Consecutive intra-gingival injections of lipopolysaccharide and butyric acid to mice induce abnormal behavior and changes in cytokine concentrations. J Neuroinflammation 2020; 17:331. [PMID: 33153485 PMCID: PMC7643404 DOI: 10.1186/s12974-020-02008-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 10/22/2020] [Indexed: 11/15/2022] Open
Abstract
Background Periodontopathic bacteria such as Porphyromonas gingivalis produce several metabolites, including lipopolysaccharide (LPS) and n-butyric acid (BA). Past work suggested that periodontal infection may cause cognitive impairment in mice. Aims To elucidate the mechanisms by which metabolites such as LPS and BA, resulting from Porphyromonas gingivalis activity, induce immunological and physiological abnormalities in mice. Methods In the present work, 28 male ICR mice were placed in an open-field arena and the total distance (cm/600 s) they covered was recorded. Based on their moving distances, mice were divided into 4 groups (n = 7) and injected the following substances into their gingival tissues for 32 consecutive days: saline (C), 5 mmol/L of BA (B), 1 μg/mouse of LPS (L), and BA-LPS (BL) solutions. Distances covered by mice were also measured on days 14 and 21, with their habituation scores considered as “(moving distance on day 14 or 21)/(moving distance on day 0)”. Afterwards, mice were dissected, and hippocampal gene expression and the concentrations of short-chain fatty acids, neurotransmitters and cytokines in their blood plasma and brains were analyzed. In addition, mouse brain and liver tissues were fixed and visually assessed for histopathological abnormalities. Results Group BL had significantly higher habituation scores than C and B on day 14. LPS induced higher habituation scores on day 21. LPS induced significant decreases in the mRNA levels of interleukin (IL)-6 and brain-derived neurotrophic factors, and an increase in neurotrophic tyrosine kinase receptor type 2. In both plasma and brain, LPS induced a significant acetate increase. Moreover, LPS significantly increased acetylcholine in brain. In plasma alone, LPS and BA significantly decreased monocyte chemoattractant protein 1 (MCP-1). However, while LPS significantly decreased tyrosine, BA significantly increased it. Lastly, LPS significantly decreased IL-6 and tumor necrosis factor in plasma. No histopathological abnormalities were detected in liver or brain tissues of mice. Conclusion We showed that injections of LPS and/or BA induced mice to move seemingly tireless and that both LPS and BA injections strongly induced a reduction of MCP-1 in blood plasma. We concluded that LPS and BA may have been crucial to induce and/or aggravate abnormal behavior in mice.
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Affiliation(s)
| | - Atsushi Toyoda
- College of Agriculture, Ibaraki University, Ibaraki, Japan.,United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Tokyo, Japan
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Wang X, Tong Y, Zhang J, Khan N, Zhang K, Bai H, Zhang Q, Chen Y. Neuroinflammation changes with periodontal inflammation status during periodontitis in wild-type mice. Oral Dis 2020; 27:1001-1011. [PMID: 32815656 DOI: 10.1111/odi.13618] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 08/09/2020] [Accepted: 08/12/2020] [Indexed: 12/20/2022]
Abstract
OBJECTIVE To investigate neuroinflammation under different periodontal status. MATERIALS AND METHODS Experimental periodontitis was induced by molar ligation (Lig group) or periodontal injection of lipopolysaccharide (LPS, Lps group). Periodontal status was assessed by alveolar bone resorption and periodontal inflammation. Micro-computed tomography and haematoxylin-eosin staining were performed to assess alveolar bone resorption and periodontal inflammation, respectively. Neuroinflammation was assessed by glial cell proliferation and proinflammatory factor expression. Microgliosis was determined by immunofluorescence. Astrogliosis was determined by immunohistochemistry. Expressions of tumour necrosis factor-alpha (TNF-α) and interleukin (IL)-1β were assessed by enzyme-linked immunosorbent assay. RESULTS Microgliosis and astrogliosis in the Lig group were notable with molar ligation for 2 weeks and 4 weeks (p < .05), but were only slightly different similar from the control group by week 12. Microgliosis and astrogliosis in the Lps group were significant with LPS injection for 4 and 8 weeks (p < .05). The groups displayed a positive correlation between the degree of periodontal inflammation and the number of glial cells (p < .05). Expressions of IL-1β and TNF-α in the Lps group were significantly increased with LPS injection for 8 weeks (p < .05). In the Lig group, only TNF-α was highly expressed with molar ligation for 12 weeks (p < .05). CONCLUSION Both models demonstrated that the inflammatory response in the hippocampus of mice can change during periodontitis depending on the periodontal inflammation status.
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Affiliation(s)
- Xu Wang
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Department of Periodontology, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Xi'an Jiaotong University, Xi'an, China
| | - Yuxin Tong
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Department of Periodontology, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Xi'an Jiaotong University, Xi'an, China
| | - Jiayu Zhang
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Department of Periodontology, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Xi'an Jiaotong University, Xi'an, China
| | - Nazia Khan
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Department of Periodontology, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Xi'an Jiaotong University, Xi'an, China
| | - Kaili Zhang
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Department of Periodontology, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Xi'an Jiaotong University, Xi'an, China
| | - Huihui Bai
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Department of Periodontology, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Xi'an Jiaotong University, Xi'an, China
| | | | - Yue Chen
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Department of Periodontology, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Xi'an Jiaotong University, Xi'an, China
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71
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Fang J, Pieper AA, Nussinov R, Lee G, Bekris L, Leverenz JB, Cummings J, Cheng F. Harnessing endophenotypes and network medicine for Alzheimer's drug repurposing. Med Res Rev 2020; 40:2386-2426. [PMID: 32656864 PMCID: PMC7561446 DOI: 10.1002/med.21709] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 06/23/2020] [Accepted: 06/27/2020] [Indexed: 12/16/2022]
Abstract
Following two decades of more than 400 clinical trials centered on the "one drug, one target, one disease" paradigm, there is still no effective disease-modifying therapy for Alzheimer's disease (AD). The inherent complexity of AD may challenge this reductionist strategy. Recent observations and advances in network medicine further indicate that AD likely shares common underlying mechanisms and intermediate pathophenotypes, or endophenotypes, with other diseases. In this review, we consider AD pathobiology, disease comorbidity, pleiotropy, and therapeutic development, and construct relevant endophenotype networks to guide future therapeutic development. Specifically, we discuss six main endophenotype hypotheses in AD: amyloidosis, tauopathy, neuroinflammation, mitochondrial dysfunction, vascular dysfunction, and lysosomal dysfunction. We further consider how this endophenotype network framework can provide advances in computational and experimental strategies for drug-repurposing and identification of new candidate therapeutic strategies for patients suffering from or at risk for AD. We highlight new opportunities for endophenotype-informed, drug discovery in AD, by exploiting multi-omics data. Integration of genomics, transcriptomics, radiomics, pharmacogenomics, and interactomics (protein-protein interactions) are essential for successful drug discovery. We describe experimental technologies for AD drug discovery including human induced pluripotent stem cells, transgenic mouse/rat models, and population-based retrospective case-control studies that may be integrated with multi-omics in a network medicine methodology. In summary, endophenotype-based network medicine methodologies will promote AD therapeutic development that will optimize the usefulness of available data and support deep phenotyping of the patient heterogeneity for personalized medicine in AD.
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Affiliation(s)
- Jiansong Fang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
- Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Andrew A Pieper
- Harrington Discovery Institute, University Hospital Case Medical Center; Department of Psychiatry, Case Western Reserve University, Geriatric Research Education and Clinical Centers, Louis Stokes Cleveland VAMC, Cleveland, OH 44106, USA
| | - Ruth Nussinov
- Cancer and Inflammation Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, National Cancer Institute at Frederick, Frederick, MD 21702, USA
- Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Garam Lee
- Cleveland Clinic Lou Ruvo Center for Brain Health, Las Vegas, NV 89106, USA
| | - Lynn Bekris
- Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, OH 44195, USA
| | - James B. Leverenz
- Lou Ruvo Center for Brain Health, Neurological Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Jeffrey Cummings
- Cleveland Clinic Lou Ruvo Center for Brain Health, Las Vegas, NV 89106, USA
- Department of Brain Health, School of Integrated Health Sciences, UNLV, Las Vegas, NV 89154, USA
| | - Feixiong Cheng
- Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, OH 44195, USA
- Case Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA
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72
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Kantarci A, Tognoni CM, Yaghmoor W, Marghalani A, Stephens D, Ahn JY, Carreras I, Dedeoglu A. Microglial response to experimental periodontitis in a murine model of Alzheimer's disease. Sci Rep 2020; 10:18561. [PMID: 33122702 PMCID: PMC7596239 DOI: 10.1038/s41598-020-75517-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Accepted: 09/30/2020] [Indexed: 12/14/2022] Open
Abstract
Periodontal disease (PD) has been suggested to be a risk factor for Alzheimer's disease (AD). We tested the impact of ligature-induced PD on 5xFAD mice and WT littermates. At baseline, 5xFAD mice presented significant alveolar bone loss compared to WT mice. After the induction of PD, both WT and 5xFAD mice experienced alveolar bone loss. PD increased the level of Iba1-immunostained microglia in WT mice. In 5xFAD mice, PD increased the level of insoluble Aβ42. The increased level in Iba1 immunostaining that parallels the accumulation of Aβ in 5xFAD mice was not affected by PD except for a decrease in the dentate gyrus. Analysis of double-label fluorescent images showed a decline in Iba1 in the proximity of Aβ plaques in 5xFAD mice with PD compared to those without PD suggesting a PD-induced decrease in plaque-associated microglia (PAM). PD reduced IL-6, MCP-1, GM-CSF, and IFN-γ in brains of WT mice and reduced IL-10 in 5xFAD mice. The data demonstrated that PD increases neuroinflammation in WT mice and disrupts the neuroinflammatory response in 5xFAD mice and suggest that microglia is central to the association between PD and AD.
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Affiliation(s)
| | - Christina M Tognoni
- Department of Veterans Affairs, VA Boston Healthcare System, Research and Development Service, Building 1A-(151), 150 S. Huntington Avenue, Boston, MA, 02130, USA.,Department of Neurology, Boston University School of Medicine, Boston, MA, 02118, USA
| | - Wael Yaghmoor
- Forsyth Institute, 245 First Street, Cambridge, MA, 02142, USA
| | - Amin Marghalani
- Forsyth Institute, 245 First Street, Cambridge, MA, 02142, USA
| | | | - Jae-Yong Ahn
- Department of Veterans Affairs, VA Boston Healthcare System, Research and Development Service, Building 1A-(151), 150 S. Huntington Avenue, Boston, MA, 02130, USA.,Department of Neurology, Boston University School of Medicine, Boston, MA, 02118, USA
| | - Isabel Carreras
- Department of Veterans Affairs, VA Boston Healthcare System, Research and Development Service, Building 1A-(151), 150 S. Huntington Avenue, Boston, MA, 02130, USA.,Department of Neurology, Boston University School of Medicine, Boston, MA, 02118, USA.,Department of Biochemistry, Boston University School of Medicine, Boston, MA, 02118, USA
| | - Alpaslan Dedeoglu
- Department of Veterans Affairs, VA Boston Healthcare System, Research and Development Service, Building 1A-(151), 150 S. Huntington Avenue, Boston, MA, 02130, USA. .,Department of Neurology, Boston University School of Medicine, Boston, MA, 02118, USA. .,Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02114, USA.
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73
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Yue Y, Liu X, Li Y, Xia B, Yu W. The role of TLR4/MyD88/NF-κB pathway in periodontitis-induced liver inflammation of rats. Oral Dis 2020; 27:1012-1021. [PMID: 32853444 PMCID: PMC8247295 DOI: 10.1111/odi.13616] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 07/24/2020] [Accepted: 08/12/2020] [Indexed: 02/07/2023]
Abstract
OBJECTIVES The aim of this study was to clarify the immune mechanism of hepatic injury induced by periodontitis using a rat model. METHODS Twenty-four SPF male Wistar rats were randomly divided into two groups: control group (CG) and periodontitis group (PG). In order to induce experimental periodontitis, we tied the wire ligature around bilateral maxillary first molar of rats. After 8 weeks, the following indicators were valued: gingival index, tooth mobility, probing pocket depth; indexes about oxidative stress and circulating biomarkers; bone retraction by micro-CT analysis; Toll-like receptor 4 (TLR4), myeloid differential protein-88 (MyD88), and nuclear factor kappa B (NF-κB) by qRT-PCR and Western blotting; tumor necrosis factor α (TNF-α), and interleukin-6 (IL-6) by qRT-PCR and immunohistochemical staining; inflammation of periodontal and hepatic tissues by histopathological observation. RESULTS Periodontal indicators and micro-CT results showed the raised levels of inflammatory response and bone retraction in PG compared with CG. The mRNA and protein levels of TLR4, MyD88, NF-κB, TNF-α, and IL-6 have indicated high values in PG versus CG. Histopathological analysis revealed a correlation between periodontitis and hepatic injury. CONCLUSION TLR4/MyD88/NF-κB pathway may play a role in periodontitis-induced liver inflammation of rats.
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Affiliation(s)
- Yiyun Yue
- Department of Periodontology, Jilin University, Changchun, China
| | - Xinchan Liu
- Department of Geriatric Stomatology, Jilin University, Changchun, China
| | - Yan Li
- Department of Periodontology, Jilin University, Changchun, China
| | - Boyuan Xia
- Department of Periodontology, Jilin University, Changchun, China
| | - Weixian Yu
- Department of Geriatric Stomatology, Jilin University, Changchun, China.,Jilin Provincial Laboratory of Biomedical Engineering, School and Hospital of Stomatology, Jilin University, Changchun, China
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74
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Kang J, Wu B, Bunce D, Ide M, Aggarwal VR, Pavitt S, Wu J. Bidirectional relations between cognitive function and oral health in ageing persons: a longitudinal cohort study. Age Ageing 2020; 49:793-799. [PMID: 32128563 DOI: 10.1093/ageing/afaa025] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 01/16/2020] [Accepted: 01/22/2020] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND evidence suggests a reciprocal relationship between cognitive function (CF) and oral health (OH), but no study has demonstrated this inter-relationship in a longitudinal population. OBJECTIVE to investigate the bidirectional relationship between CF and OH in an ageing cohort. DESIGN cohort study. SETTING general community. SUBJECTS participants from the English Longitudinal Study of Ageing. METHODS OH, measured by teeth status, self-reported OH and OH-related quality of life (OHRQoL), and CFs were collected at three time points in 2006/07, 2010/11 and 2014/15. Cross-lagged structural equation models were used to investigate the association between CF and OH, adjusted for potential confounding factors. RESULTS 5477 individuals (56.4% women) were included (mean age = 63.1 years at 2006/07, 67.2 at 2010/11 and 70.4 at 2014/15, SD = 8.9) in analyses. The average CF score was 46.5(SD = 12.3) at baseline and 41.2 (SD = 13.4) at follow-up. 3350 (61.2%) participants had natural teeth only and 622 (11.2%) were edentulous. In the fully adjusted model, better cognition at baseline was associated with better OH at follow-up (beta coefficient = 0.02, 95% CI: 0.01-0.03); conversely better OH at baseline predicted better cognition (beta coefficient = 0.12, 95% CI: 0.06-0.18). Similar magnitude and direction of the reciprocal association was evident between cognition and OHRQoL. CONCLUSIONS This is the first longitudinal study to demonstrate the positive reciprocal association between CF and OH. The findings suggest the importance of maintaining both good CF and OH in old age.
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Affiliation(s)
- Jing Kang
- Division of Oral Biology, School of Dentistry, University of Leeds, Leeds, UK
| | - Bei Wu
- Rory Meyers College of Nursing, Hartford Institute of Geriatric Nursing, New York University, New York, USA
| | - David Bunce
- School of Psychology, Faculty of Medicine and Health, University of Leeds, Leeds, UK
| | - Mark Ide
- Dental Institute, Kings College London, London, UK
| | - Vishal R Aggarwal
- Division of Oral Medicine, Oral Surgery, Oral Pathology and Radiology, School of Dentistry, University of Leeds, Leeds, UK
| | - Sue Pavitt
- Division of Applied Health and Clinical Translation, School of Dentistry, University of Leeds, Leeds, UK
| | - Jianhua Wu
- Division of Applied Health and Clinical Translation, School of Dentistry, University of Leeds, Leeds, UK
- Leeds Institute for Data Analytics, University of Leeds, Leeds, UK
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75
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Ryder MI. Porphyromonas gingivalis and Alzheimer disease: Recent findings and potential therapies. J Periodontol 2020; 91 Suppl 1:S45-S49. [PMID: 32533852 PMCID: PMC7689719 DOI: 10.1002/jper.20-0104] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 04/06/2020] [Accepted: 04/19/2020] [Indexed: 12/12/2022]
Abstract
Epidemiological studies have identified an association between periodontitis and Alzheimer disease (AD); however, the nature of this association has been unclear. Recent work suggests that brain colonization by the periodontal pathogen Porphyromonas gingivalis may link these two inflammatory and degenerative conditions. Evidence of P. gingivalis infiltration has been detected in autopsy specimens from the brains of people with AD and in cerebrospinal fluid of individuals diagnosed with AD. Gingipains, a class of P. gingivalis proteases, are found in association with neurons, tau tangles, and beta-amyloid in specimens from the brains of individuals with AD. The brains of mice orally infected with P. gingivalis show evidence of P. gingivalis infiltration, along with various neuropathological hallmarks of AD. Oral administration of gingipain inhibitors to mice with established brain infections decreases the abundance of P. gingivalis DNA in brain and mitigates the neurotoxic effects of P. gingivalis infection. Thus, gingipain inhibition could provide a potential approach to the treatment of both periodontitis and AD.
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Affiliation(s)
- Mark I Ryder
- Division of Periodontology, Department of Orofacial Sciences School of Dentistry, University of California, San Francisco, CA
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76
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Kamer AR, Craig RG, Niederman R, Fortea J, de Leon MJ. Periodontal disease as a possible cause for Alzheimer's disease. Periodontol 2000 2020; 83:242-271. [PMID: 32385876 DOI: 10.1111/prd.12327] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 06/23/2019] [Indexed: 12/13/2022]
Abstract
Approximately 47 million people worldwide have been diagnosed with dementia, 60%-80% of whom have dementia of the Alzheimer's disease type. Unfortunately, there is no cure in sight. Defining modifiable risk factors for Alzheimer's disease may have a significant impact on its prevalence. An increasing body of evidence suggests that chronic inflammation and microbial dysbiosis are risk factors for Alzheimer's disease. Periodontal disease is a chronic inflammatory disease that develops in response to response to microbial dysbiosis. Many studies have shown an association between periodontal disease and Alzheimer's disease. The intent of this paper was to review the existing literature and determine, using the Bradford Hill criteria, whether periodontal disease is causally related to Alzheimer's disease.
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Affiliation(s)
- Angela R Kamer
- Department of Periodontology and Implant Dentistry, New York University, College of Dentistry, New York, New York, USA
| | - Ronald G Craig
- Department of Periodontology and Implant Dentistry, New York University, College of Dentistry, New York, New York, USA.,Department of Basic Sciences and Craniofacial Biology, New York University, College of Dentistry, New York, New York, USA
| | - Richard Niederman
- Department of Epidemiology and Health Promotion, New York University, College of Dentistry, New York, New York, USA
| | - Juan Fortea
- Alzheimer Down Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau- Biomedical Research Institute Sant Pau- Universitat Autònoma de Barcelona and Barcelona Down Medical Center, Fundació Catalana Síndrome de Down, Barcelona, Spain.,Alzheimer's Disease and Other Cognitive Disorders Unit, Neurology Service, Hospital Clínic, Barcelona, Spain
| | - Mony J de Leon
- Department of Radiology, Brain Health Imaging Institute, Weill Cornell Medicine, New York, New York, USA
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77
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Effects of Porphyromonas gingivalis and Its Underlying Mechanisms on Alzheimer-Like Tau Hyperphosphorylation in Sprague-Dawley Rats. J Mol Neurosci 2020; 71:89-100. [DOI: 10.1007/s12031-020-01629-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 06/08/2020] [Indexed: 01/12/2023]
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78
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Invasion of Human Retinal Pigment Epithelial Cells by Porphyromonas gingivalis leading to Vacuolar/Cytosolic localization and Autophagy dysfunction In-Vitro. Sci Rep 2020; 10:7468. [PMID: 32366945 PMCID: PMC7198524 DOI: 10.1038/s41598-020-64449-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 04/15/2020] [Indexed: 02/06/2023] Open
Abstract
Recent epidemiological studies link Periodontal disease(PD) to age-related macular degeneration (AMD). We documented earlier that Porphyromonas gingivalis(Pg), keystone oral-pathobiont, causative of PD, efficiently invades human gingival epithelial and blood-dendritic cells. Here, we investigated the ability of dysbiotic Pg-strains to invade human-retinal pigment epithelial cells(ARPE-19), their survival, intracellular localization, and the pathological effects, as dysfunction of RPEs leads to AMD. We show that live, but not heat-killed Pg-strains adhere to and invade ARPEs. This involves early adhesion to ARPE cell membrane, internalization and localization of Pg within single-membrane vacuoles or cytosol, with some nuclear localization apparent. No degradation of Pg or localization inside double-membrane autophagosomes was evident, with dividing Pg suggesting a metabolically active state during invasion. We found significant downregulation of autophagy-related genes particularly, autophagosome complex. Antibiotic protection-based recovery assay further confirmed distinct processes of adhesion, invasion and amplification of Pg within ARPE cells. This is the first study to demonstrate invasion of human-RPEs, begin to characterize intracellular localization and survival of Pg within these cells. Collectively, invasion of RPE by Pg and its prolonged survival by autophagy evasion within these cells suggest a strong rationale for studying the link between oral infection and AMD pathogenesis in individuals with periodontitis.
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79
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Vargas-Caraveo A, Sayd A, Robledo-Montaña J, Caso JR, Madrigal JLM, García-Bueno B, Leza JC. Toll-like receptor 4 agonist and antagonist lipopolysaccharides modify innate immune response in rat brain circumventricular organs. J Neuroinflammation 2020; 17:6. [PMID: 31906991 PMCID: PMC6945636 DOI: 10.1186/s12974-019-1690-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 12/23/2019] [Indexed: 01/02/2023] Open
Abstract
Background The circumventricular organs (CVOs) are blood-brain-barrier missing structures whose activation through lipopolysaccharide (LPS) is a starting point for TLR-driven (Toll-like receptors) neuroinflammation. The aim of this study was to evaluate in the CVO area postrema (AP), subfornical organ (SFO), and median eminence (ME), the inflammatory response to two TLR4 agonists: LPS from Escherichia coli (EC-LPS), the strongest endotoxin molecule described, and LPS from Porphyromonas gingivalis (PG-LPS), a pathogenic bacteria present in the periodontium related to neuroinflammation in neurodegenerative/psychiatric diseases. The response to LPS from the cyanobacteria Rhodobacter sphaeroides (RS-LPS), a TLR4 antagonist with an interesting anti-inflammatory potential, was also assessed. Methods LPSs were intraperitoneally administered to Wistar rats and, as indicatives of neuroinflammation in CVOs, the cellular localization of the nuclear factor NF-κB was studied by immunofluorescence, and microglia morphology was quantified by fractal and skeleton analysis. Results Data showed that EC-LPS increased NF-κB nuclear translocation in the three CVOs studied and PG-LPS only induced NF-κB nuclear translocation in the ME. RS-LPS showed no difference in NF-κB nuclear translocation compared to control. Microglia in the three CVOs showed an ameboid-shape after EC-LPS exposure, whereas PG-LPS only elicited a mild tendency to induce an ameboid shape. On the other hand, RS-LPS produced a markedly elongated morphology described as “rod” microglia in the three CVOs. Conclusions In conclusion, at the doses tested, EC-LPS induces a stronger neuroinflammatory response than PG-LPS in CVOs, which might be related to their different potency as TLR4 agonists. The non-reduction of basal NF-κB activation and induction of rod microglia by RS-LPS, a cell morphology only present in severe brain injury and infections, suggests that this molecule must be carefully studied before being proposed as an anti-inflammatory treatment for neuroinflammation related to neurodegenerative/psychiatric diseases.
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Affiliation(s)
- Alejandra Vargas-Caraveo
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid (UCM); Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM); Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12); Instituto Universitario de Investigación en Neuroquímica UCM, Avda. Complutense s/n, 28040, Madrid, Spain. .,Biological and Health Sciences Division, Metropolitan Autonomous University (UAM), Campus Lerma, 52005, Lerma, Mexico.
| | - Aline Sayd
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid (UCM); Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM); Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12); Instituto Universitario de Investigación en Neuroquímica UCM, Avda. Complutense s/n, 28040, Madrid, Spain
| | - Javier Robledo-Montaña
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid (UCM); Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM); Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12); Instituto Universitario de Investigación en Neuroquímica UCM, Avda. Complutense s/n, 28040, Madrid, Spain
| | - Javier R Caso
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid (UCM); Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM); Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12); Instituto Universitario de Investigación en Neuroquímica UCM, Avda. Complutense s/n, 28040, Madrid, Spain
| | - José L M Madrigal
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid (UCM); Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM); Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12); Instituto Universitario de Investigación en Neuroquímica UCM, Avda. Complutense s/n, 28040, Madrid, Spain
| | - Borja García-Bueno
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid (UCM); Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM); Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12); Instituto Universitario de Investigación en Neuroquímica UCM, Avda. Complutense s/n, 28040, Madrid, Spain.
| | - Juan C Leza
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid (UCM); Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM); Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12); Instituto Universitario de Investigación en Neuroquímica UCM, Avda. Complutense s/n, 28040, Madrid, Spain
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80
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Olsen I, Singhrao SK. Is there a link between genetic defects in the complement cascade and Porphyromonas gingivalis in Alzheimer's disease? J Oral Microbiol 2019; 12:1676486. [PMID: 31893014 PMCID: PMC6818111 DOI: 10.1080/20002297.2019.1676486] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 09/17/2019] [Indexed: 12/18/2022] Open
Abstract
Defects, as determined by Genome-Wide Association Studies (GWAS), in the complement cascade of innate immunity have been suggested to play a key role in Alzheimer's disease (AD). These defective genes encode sub-component 1s (C1s), complement receptor 1, complement component 9, and clusterin, a fluid-phase regulatory protein. A dysregulated complement cascade has been shown to relate to cell activation, defective complement mediated clearance and possible cognitive decline in AD patients. Porphyromonas gingivalis, a putative keystone pathogen of periodontal disease, has been reported to be associated with human AD. The inflammatory burden following experimental oral infection in mice and putative entry of this bacterium into the brain appears to drive the formation of amyloid-beta plaques and neurofibrillary tangles with loss of cognition. P. gingivalis is a master of immune subversion in this inflammatory cascade and may establish microbial dysbiosis where it is located. Here we discuss if P. gingivalis may enhance the detrimental effects of the defective GWAS complement cascade protein genes.
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Affiliation(s)
- Ingar Olsen
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Sim K Singhrao
- Dementia and Neurodegenerative Diseases Research Group, Faculty of Clinical and Biomedical Sciences, School of Dentistry, University of Central Lancashire, Preston, UK
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81
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Systemic inflammation linking chronic periodontitis to cognitive decline. Brain Behav Immun 2019; 81:63-73. [PMID: 31279681 DOI: 10.1016/j.bbi.2019.07.002] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 07/03/2019] [Accepted: 07/03/2019] [Indexed: 12/25/2022] Open
Abstract
Persistent inflammation in the systemic immune system can impose detrimental effects on the central nervous system (CNS). Neuroinflammation might be a result of this to accelerate the progressive deterioration of neuronal functions during aging. In this regard, controlling inflammation through delaying and/or preventing chronic inflammatory diseases may be a potential strategy to prevent or modify the progression of Alzheimer's Disease (AD). Periodontitis is a chronic inflammatory disease of the oral cavity that is common among the elderly, especially for those who have decline in cognitive functions. While epidemiological findings support the association of chronic periodontitis and cognitive decline, whether they have causal relationship remains unclear. Nonetheless, the possibility that periodontopathogens, systemic immune cells and inflammatory cytokines could reach the CNS should not be overlooked. The impacts of periodontitis on CNS homeostasis and inflammation as a pathophysiological factor concerning the association between periodontitis and AD will be discussed in this review. Future work should elucidate the pathological pathways involved in periodontitis-induced cerebral infections and inflammation, and define the role of the latter in AD progression.
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82
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Ding X, Li X, Li C, Qi M, Zhang Z, Sun X, Wang L, Zhou Y. Chitosan/Dextran Hydrogel Constructs Containing Strontium-Doped Hydroxyapatite with Enhanced Osteogenic Potential in Rat Cranium. ACS Biomater Sci Eng 2019; 5:4574-4586. [DOI: 10.1021/acsbiomaterials.9b00584] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
| | | | | | | | - Zhe Zhang
- Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People’s Republic of China
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83
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Hashioka S, Inoue K, Miyaoka T, Hayashida M, Wake R, Oh-Nishi A, Inagaki M. The Possible Causal Link of Periodontitis to Neuropsychiatric Disorders: More Than Psychosocial Mechanisms. Int J Mol Sci 2019; 20:E3723. [PMID: 31366073 PMCID: PMC6695849 DOI: 10.3390/ijms20153723] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 07/19/2019] [Accepted: 07/25/2019] [Indexed: 12/27/2022] Open
Abstract
Increasing evidence implies a possible causal link between periodontitis and neuropsychiatric disorders, such as Alzheimer's disease (AD) and major depression (MD). A possible mechanism underlying such a link can be explained by neuroinflammation induced by chronic systemic inflammation. This review article focuses on an overview of the biological and epidemiological evidence for a feasible causal link of periodontitis to neuropsychiatric disorders, including AD, MD, Parkinson's disease, and schizophrenia, as well as the neurological event, ischemic stroke. If there is such a link, a broad spectrum of neuropsychiatric disorders associated with neuroinflammation could be preventable and modifiable by simple daily dealings for oral hygiene. However, the notion that periodontitis is a risk factor for neuropsychiatric disorders remains to be effectively substantiated.
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Affiliation(s)
- Sadayuki Hashioka
- Department of Psychiatry, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan.
| | - Ken Inoue
- Health Service Center, Kochi University, 2-5-1 Akebono-cho, Kochi 780-8520, Japan
| | - Tsuyoshi Miyaoka
- Department of Psychiatry, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan
| | - Maiko Hayashida
- Department of Psychiatry, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan
| | - Rei Wake
- Department of Psychiatry, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan
| | - Arata Oh-Nishi
- Department of Psychiatry, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan
| | - Masatoshi Inagaki
- Department of Psychiatry, Shimane University, 89-1 Enya-cho, Izumo 693-8501, Japan
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84
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Patrick KL, Bell SL, Weindel CG, Watson RO. Exploring the "Multiple-Hit Hypothesis" of Neurodegenerative Disease: Bacterial Infection Comes Up to Bat. Front Cell Infect Microbiol 2019; 9:138. [PMID: 31192157 PMCID: PMC6546885 DOI: 10.3389/fcimb.2019.00138] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 04/16/2019] [Indexed: 12/23/2022] Open
Abstract
Despite major strides in personalized genomics, it remains poorly understood why neurodegenerative diseases occur in only a fraction of individuals with a genetic predisposition and conversely, why individuals with no genetic risk of a disorder develop one. Chronic diseases like Alzheimer's, Parkinson's, and Multiple sclerosis are speculated to result from a combination of genetic and environmental factors, a concept commonly referred to as the “multiple hit hypothesis.” A number of bacterial infections have been linked to increased risk of neurodegeneration, and in some cases, clearance of bacterial pathogens has been correlated with amelioration of central nervous system (CNS) deficits. Additionally, mutations in several genes known to contribute to CNS disorders like Parkinson's Disease have repeatedly been implicated in susceptibility to intracellular bacterial infection. Recent data has begun to demonstrate roles for these genes (PARK2, PINK1, and LRRK2) in modulating innate immune outcomes, suggesting that immune dysregulation may play an even more important role in neurodegeneration than previously appreciated. This review will broadly explore the connections between bacterial infection, immune dysregulation, and CNS disorders. Understanding this interplay and how bacterial pathogenesis contributes to the “multiple-hit hypothesis” of neurodegeneration will be crucial to develop therapeutics to effectively treat both neurodegeneration and infection.
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Affiliation(s)
- Kristin L Patrick
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX, United States
| | - Samantha L Bell
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX, United States
| | - Chi G Weindel
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX, United States
| | - Robert O Watson
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX, United States
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85
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Díaz-Zúñiga J, Muñoz Y, Melgar-Rodríguez S, More J, Bruna B, Lobos P, Monasterio G, Vernal R, Paula-Lima A. Serotype b of Aggregatibacter actinomycetemcomitans triggers pro-inflammatory responses and amyloid beta secretion in hippocampal cells: a novel link between periodontitis and Alzheimer´s disease? J Oral Microbiol 2019; 11:1586423. [PMID: 31044031 PMCID: PMC6484476 DOI: 10.1080/20002297.2019.1586423] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 01/31/2019] [Accepted: 02/13/2019] [Indexed: 01/18/2023] Open
Abstract
Introduction: Previous reports have proposed that Periodontal disease (PDis) predisposes to Alzheimer's disease (AD), both highly prevalent pathologies among the elderly. The bacteria Aggregatibacter actinomycetemcomitans (Aa), associated with the most aggressive forms of PDis, are classified in different serotypes with distinct virulence according to the antigenicity of their lipopolysaccharide (LPS). Methods: Here, we determined the effects of purified LPS, from serotypes a, b or c of Aa, on primary cultures of microglia or mixed hippocampal cells. Results: We found that both culture types exhibited higher levels of inflammatory cytokines (IL-1β, IL-6 and TNFα) when treated with serotype b-LPS, compared with controls, as quantified by qPCR and/or ELISA. Also, cultures treated with serotype a-LPS displayed increased mRNA levels of the modulatory cytokines IL-4 and IL-10. Mixed hippocampal cultures treated with serotype b-LPS exhibited severe neuronal morphological changes and displayed increased levels of secreted Aβ1-42 peptide. These results indicate that LPS from different Aa serotypes triggers discriminatory immune responses, which differentially affect primary hippocampal cells. Conclusion: Altogether, our results show that treatment with serotype b-LPS triggers the secretion of proinflammatory cytokines by microglia, induces neurite shrinking, and increases the extracellular Aβ1-42 levels, all features strongly associated with the etiology of AD.
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Affiliation(s)
- J Díaz-Zúñiga
- Department of Conservative Dentistry, Faculty of Dentistry, Universidad de Chile, Santiago, Chile.,Biomedical Neuroscience Institute, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Y Muñoz
- Aging Cellular Laboratory, Faculty of Sciences, Universidad de Chile, Santiago, Chile
| | - S Melgar-Rodríguez
- Department of Conservative Dentistry, Faculty of Dentistry, Universidad de Chile, Santiago, Chile
| | - J More
- Biomedical Neuroscience Institute, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - B Bruna
- Biomedical Neuroscience Institute, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - P Lobos
- Biomedical Neuroscience Institute, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - G Monasterio
- Department of Conservative Dentistry, Faculty of Dentistry, Universidad de Chile, Santiago, Chile
| | - R Vernal
- Department of Conservative Dentistry, Faculty of Dentistry, Universidad de Chile, Santiago, Chile.,Dentistry Unit, Faculty of Health Sciences, Universidad Autónoma de Chile, Temuco, Chile
| | - A Paula-Lima
- Biomedical Neuroscience Institute, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,Institute for Research in Dental Sciences, Faculty of Dentistry, Universidad de Chile, Santiago, Chile
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86
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Poor Oral Health and Its Neurological Consequences: Mechanisms of Porphyromonas gingivalis Involvement in Cognitive Dysfunction. ACTA ACUST UNITED AC 2019. [DOI: 10.1007/s40496-019-0212-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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87
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Singhrao SK, Olsen I. Assessing the role of Porphyromonas gingivalis in periodontitis to determine a causative relationship with Alzheimer's disease. J Oral Microbiol 2019; 11:1563405. [PMID: 30728914 PMCID: PMC6352933 DOI: 10.1080/20002297.2018.1563405] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 12/05/2018] [Accepted: 12/13/2018] [Indexed: 01/14/2023] Open
Abstract
Chronic periodontitis of 10 years' duration is reported to become a twofold risk factor for the development of Alzheimer's disease (AD). Periodontitis is modifiable, and this fits with the current action plan for preventing AD. However, until periodontitis, becomes acknowledged as a firm risk factor for AD, this risk will continue. Here, we put forward our own argument based on the current literature for in vivo infection-mediated periodontal disease models supporting the antimicrobial protection hypothesis of AD and interventional studies supporting the causal links. Oral infections with Porphyromonas gingivalis, or introduction of its lipopolysaccharide (LPS), in various mouse models has demonstrated the development of key neuropathological hallmark lesions defining AD. These are extracellular amyloid-beta plaques, phosphorylated tau, neurofibrillary tangles, widespread acute and chronic inflammation, blood-brain barrier defects together with the clinical phenotype showing impaired learning and spatial memory. Live P. gingivalis and its LPS (commercial or from 'microbullets') are powerful peripheral and intracerebral inflammatory signalling initiators, and this has direct implications on memory and lesion development. Maintaining a healthy oral microbiome and managing periodontal disease with regular surveillance and good oral hygiene throughout life is likely to reduce the unnecessary burden of AD in some individuals.
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Affiliation(s)
- Sim K Singhrao
- Dementia and Neurodegenerative Diseases Research Group, Faculty of Clinical and Biomedical Sciences, School of Dentistry, University of Central Lancashire, Preston, UK
| | - Ingar Olsen
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
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88
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Singhrao SK, Olsen I. Are Porphyromonas gingivalis Outer Membrane Vesicles Microbullets for Sporadic Alzheimer's Disease Manifestation? J Alzheimers Dis Rep 2018; 2:219-228. [PMID: 30599043 PMCID: PMC6311351 DOI: 10.3233/adr-180080] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Our research into Alzheimer's disease (AD) focuses on the oral cavity and the brain, from which key evaluations of prospective and retrospective population-based data have shown that chronic periodontal disease existing for ten-years or over doubles the risk for the sporadic form of AD. Furthermore, Porphyromonas gingivalis (P. gingivalis) mono-infections in established periodontal lesions, or introducing its lipopolysachharide (LPS), as demonstrated in in vivo studies, show hallmark pathology inclusive of extracellular amyloid plaques and phospho-tau bound neurofibrillary tangles with AD-like phenotype. Other studies have shown that if periodontitis remains untreated in human AD patients, cognitive decline ensues. This is a bi-directional relationship meaning that the converse is also true; treating periodontal disease in AD patients improves memory. Bacterial cultures and established oral biofilms generate vast numbers of microvesicles and P. gingivalis outer membrane vesicles encase key virulence factors (LPS, gingipains, capsule, fimbriae) as though they are complete destructive "microbullets" when shed in the host. This provides P. gingivalis additional arsenal to manipulate its entry into disparate organs, hijack phagocytosis, destroy tissues, and affect complement related genes while transducing the onset of proinflammatory signaling cascades. The resulting inflammatory mediators may be the cause of disease defining lesions and cognitive decline typical of clinical AD.
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Affiliation(s)
- Sim K Singhrao
- Dementia and Neurodegenerative Diseases Research Group, Faculty of Clinical and Biomedical Sciences, School of Dentistry, University of Central Lancashire, Preston, UK
| | - Ingar Olsen
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
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89
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Giau VV, Wu SY, Jamerlan A, An SSA, Kim SY, Hulme J. Gut Microbiota and Their Neuroinflammatory Implications in Alzheimer's Disease. Nutrients 2018; 10:nu10111765. [PMID: 30441866 PMCID: PMC6266223 DOI: 10.3390/nu10111765] [Citation(s) in RCA: 143] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 11/08/2018] [Accepted: 11/10/2018] [Indexed: 12/12/2022] Open
Abstract
The bidirectional communication between the central nervous system (CNS) and the gut microbiota plays a pivotal role in human health. Increasing numbers of studies suggest that the gut microbiota can influence the brain and behavior of patients. Various metabolites secreted by the gut microbiota can affect the cognitive ability of patients diagnosed with neurodegenerative diseases. Nearly one in every ten Korean senior citizens suffers from Alzheimer’s disease (AD), the most common form of dementia. This review highlights the impact of metabolites from the gut microbiota on communication pathways between the brain and gut, as well as the neuroinflammatory roles they may have in AD patients. The objectives of this review are as follows: (1) to examine the role of the intestinal microbiota in homeostatic communication between the gut microbiota and the brain, termed the microbiota–gut–brain (MGB) axis; (2) to determine the underlying mechanisms of signal dysfunction; and (3) to assess the impact of signal dysfunction induced by the microbiota on AD. This review will aid in understanding the microbiota of elderly people and the neuroinflammatory roles they may have in AD.
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Affiliation(s)
- Vo Van Giau
- Department of Bionano Technology, Gachon Bionano Research Institute, Gachon University, 1342 Sungnam-daero, Seongnam-si, Gyeonggi-do 461-701, Korea.
| | - Si Ying Wu
- Department of Bionano Technology, Gachon Bionano Research Institute, Gachon University, 1342 Sungnam-daero, Seongnam-si, Gyeonggi-do 461-701, Korea.
| | - Angelo Jamerlan
- Department of Bionano Technology, Gachon Bionano Research Institute, Gachon University, 1342 Sungnam-daero, Seongnam-si, Gyeonggi-do 461-701, Korea.
| | - Seong Soo A An
- Department of Bionano Technology, Gachon Bionano Research Institute, Gachon University, 1342 Sungnam-daero, Seongnam-si, Gyeonggi-do 461-701, Korea.
| | - Sang Yun Kim
- Department of Neurology, Seoul National University College of Medicine & Neurocognitive Behavior Center, Seoul National University Bundang Hospital, Seoul 100-011, Korea.
| | - John Hulme
- Department of Bionano Technology, Gachon Bionano Research Institute, Gachon University, 1342 Sungnam-daero, Seongnam-si, Gyeonggi-do 461-701, Korea.
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90
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Tchessalova D, Posillico CK, Tronson NC. Neuroimmune Activation Drives Multiple Brain States. Front Syst Neurosci 2018; 12:39. [PMID: 30210310 PMCID: PMC6123349 DOI: 10.3389/fnsys.2018.00039] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 08/07/2018] [Indexed: 12/11/2022] Open
Abstract
Neuroimmune signaling is increasingly identified as a critical component of neuronal processes underlying memory, emotion and cognition. The interactions of microglia and astrocytes with neurons and synapses, and the individual cytokines and immune signaling molecules that mediate these interactions are a current focus of much research. Here, we discuss neuroimmune activation as a mechanism triggering different states that modulate cognitive and affective processes to allow for appropriate behavior during and after illness or injury. We propose that these states lie on a continuum from a naïve homeostatic baseline state in the absence of stimulation, to acute neuroimmune activity and chronic activation. Importantly, consequences of illness or injury including cognitive deficits and mood impairments can persist long after resolution of immune signaling. This suggests that neuroimmune activation also results in an enduring shift in the homeostatic baseline state with long lasting consequences for neural function and behavior. Such different states can be identified in a multidimensional way, using patterns of cytokine and glial activation, behavioral and cognitive changes, and epigenetic signatures. Identifying distinct neuroimmune states and their consequences for neural function will provide a framework for predicting vulnerability to disorders of memory, cognition and emotion both during and long after recovery from illness.
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Affiliation(s)
- Daria Tchessalova
- Neuroscience Graduate Program, School of Medicine, University of Michigan, Ann Arbor, MI, United States
| | | | - Natalie Celia Tronson
- Neuroscience Graduate Program, School of Medicine, University of Michigan, Ann Arbor, MI, United States.,Department of Psychology, University of Michigan, Ann Arbor, MI, United States
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