1
|
Chen S, Han C, Wang X, Zhang Q, Yang X. Alantolactone improves cognitive impairment in rats with Porphyromonas gingivalis infection by inhibiting neuroinflammation, oxidative stress, and reducing Aβ levels. Brain Res 2024; 1845:149203. [PMID: 39208968 DOI: 10.1016/j.brainres.2024.149203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2024] [Revised: 07/20/2024] [Accepted: 08/25/2024] [Indexed: 09/04/2024]
Abstract
Neuroinflammation caused by the chronic periodontal pathogen Porphyromonas gingivalis is growing regarded as as a key factor in the pathogenesis of Alzheimer's disease (AD). Alantolactone (AL), a sesquiterpene lactone isolated from the root of Inula racemosa Hook. f, has been proven to provide various neuroprotective effects. However, whether AL can improve cognitive impairment caused by P. gingivalis infection remains unclear. In this research, a rat model of P. gingivalis infection was used to examine the neuroprotective benefits of AL. The results revealed that 6 weeks of AL treatment (50 and 100 mg/kg) shortened escape latency and increased the number of crossings over the platform location and time spent in the target quadrant of P. gingivalis-infected rats in the Morris water maze experiment. By activating the Nrf2/HO-1 pathway, AL suppressed malondialdehyde (MDA) levels and simultaneously increased the activity of total superoxide dismutase (T-SOD). Furthermore, AL lowered the presence of IL-6, IL-1β, and TNFα in the hippocampal and cortical tissues of P. gingivalis-infected rats by inhibiting astrocyte and microglial activation and NF-κB phosphorylation. AL also significantly reduced Aβ levels in the cortical and hippocampus tissues of rats infected with P. gingivalis. In conclusion, AL improved cognitive impairment in P. gingivalis-infected rats by inhibiting neuroinflammation, reducing Aβ1-42 level, and exerting antioxidative stress effects.
Collapse
Affiliation(s)
| | - Cheng Han
- Qinghai University Graduate School, Xining, China
| | - XinHao Wang
- Qinghai University Graduate School, Xining, China
| | - QingXin Zhang
- Department of Magnetic Resonance, Qinghai Provincial People's Hospital, Xining 810000, China.
| | - XiaoLi Yang
- Department of Neurology, Qinghai Provincial People's Hospital, Xining 810000, China.
| |
Collapse
|
2
|
Bezerra B, Fisher M, Pirih FQ, Casarin M. The potential impact of periodontitis on cerebral small vessel disease. Mol Oral Microbiol 2024; 39:190-198. [PMID: 37929810 DOI: 10.1111/omi.12443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 08/11/2023] [Accepted: 10/16/2023] [Indexed: 11/07/2023]
Abstract
Cerebral small vessel disease (CSVD) is a term used to describe abnormalities in the intracranial microvasculature affecting small arteries, arterioles, capillaries, and venules. The etiology of these conditions is not fully understood but inflammation appears to play a significant role. Periodontal diseases have been associated with conditions such as stroke and dementia, which are clinical consequences of CSVD. Periodontitis is a highly prevalent chronic multifactorial inflammatory disease regulated by the host immune response against pathogenic bacterial colonization around the teeth. The inflammatory response and the microbial dysbiosis produce pro-inflammatory cytokines that can reach the brain and promote local changes. This review will explore the potential association between periodontitis and CSVD by assessing the impact of periodontitis-induced inflammation and periodontopathogenic bacteria on the underlying mechanisms leading to CSVD. Given the association of periodontitis with stroke and dementia, which are clinical features of CSVD, it may be possible to suggest a link with CSVD. Current evidence linking periodontitis with neuroimaging findings of CSVD enforces the possible link between these conditions.
Collapse
Affiliation(s)
- Beatriz Bezerra
- Section of Periodontics, UCLA School of Dentistry, Los Angeles, California, USA
| | - Mark Fisher
- Department of Neurology, UC Irvine Medical Center, Orange, California, USA
| | - Flavia Q Pirih
- Section of Periodontics, UCLA School of Dentistry, Los Angeles, California, USA
| | - Maísa Casarin
- Section of Periodontics, UCLA School of Dentistry, Los Angeles, California, USA
- School of Dentistry, Federal University of Pelotas, Pelotas, Brazil
| |
Collapse
|
3
|
Li F, Ma C, Lei S, Pan Y, Lin L, Pan C, Li Q, Geng F, Min D, Tang X. Gingipains may be one of the key virulence factors of Porphyromonas gingivalis to impair cognition and enhance blood-brain barrier permeability: An animal study. J Clin Periodontol 2024; 51:818-839. [PMID: 38414291 DOI: 10.1111/jcpe.13966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 01/24/2024] [Accepted: 02/08/2024] [Indexed: 02/29/2024]
Abstract
AIM Blood-brain barrier (BBB) disorder is one of the early findings in cognitive impairments. We have recently found that Porphyromonas gingivalis bacteraemia can cause cognitive impairment and increased BBB permeability. This study aimed to find out the possible key virulence factors of P. gingivalis contributing to the pathological process. MATERIALS AND METHODS C57/BL6 mice were infected with P. gingivalis or gingipains or P. gingivalis lipopolysaccharide (P. gingivalis LPS group) by tail vein injection for 8 weeks. The cognitive behaviour changes in mice, the histopathological changes in the hippocampus and cerebral cortex, the alternations of BBB permeability, and the changes in Mfsd2a and Cav-1 levels were measured. The mechanisms of Ddx3x-induced regulation on Mfsd2a by arginine-specific gingipain A (RgpA) in BMECs were explored. RESULTS P. gingivalis and gingipains significantly promoted mice cognitive impairment, pathological changes in the hippocampus and cerebral cortex, increased BBB permeability, inhibited Mfsd2a expression and up-regulated Cav-1 expression. After RgpA stimulation, the permeability of the BBB model in vitro increased, and the Ddx3x/Mfsd2a/Cav-1 regulatory axis was activated. CONCLUSIONS Gingipains may be one of the key virulence factors of P. gingivalis to impair cognition and enhance BBB permeability by the Ddx3x/Mfsd2a/Cav-1 axis.
Collapse
Affiliation(s)
- Fulong Li
- Department of Periodontics, School and Hospital of Stomatology, Liaoning Provincial Key Laboratory of Oral Disease, China Medical University, Shenyang, China
- Center of Implantology, School and Hospital of Stomatology, Liaoning Provincial Key Laboratory of Oral Disease, China Medical University, Shenyang, China
| | - Chunliang Ma
- Department of Periodontics, School and Hospital of Stomatology, Liaoning Provincial Key Laboratory of Oral Disease, China Medical University, Shenyang, China
| | - Shuang Lei
- Department of Pediatric Dentistry, School and Hospital of Stomatology, Liaoning Provincial Key Laboratory of Oral Disease, China Medical University, Shenyang, China
| | - Yaping Pan
- Department of Periodontics, School and Hospital of Stomatology, Liaoning Provincial Key Laboratory of Oral Disease, China Medical University, Shenyang, China
| | - Li Lin
- Department of Periodontics, School and Hospital of Stomatology, Liaoning Provincial Key Laboratory of Oral Disease, China Medical University, Shenyang, China
| | - Chunling Pan
- Department of Periodontics, School and Hospital of Stomatology, Liaoning Provincial Key Laboratory of Oral Disease, China Medical University, Shenyang, China
| | - Qian Li
- Department of Periodontics, School and Hospital of Stomatology, Liaoning Provincial Key Laboratory of Oral Disease, China Medical University, Shenyang, China
| | - Fengxue Geng
- Department of Periodontics, School and Hospital of Stomatology, Liaoning Provincial Key Laboratory of Oral Disease, China Medical University, Shenyang, China
| | - Dongyu Min
- Traditional Chinese Medicine Experimental Center, Affiliated Hospital of Liaoning University of Traditional Chinese Medicine, Shenyang, China
- Key Laboratory of Ministry of Education for TCM Viscera State Theory and Applications, Liaoning University of Traditional Chinese Medicine, Shenyang, China
| | - Xiaolin Tang
- Department of Periodontics, School and Hospital of Stomatology, Liaoning Provincial Key Laboratory of Oral Disease, China Medical University, Shenyang, China
| |
Collapse
|
4
|
Sharon N, Yarmolinsky L, Khalfin B, Fleisher-Berkovich S, Ben-Shabat S. Cannabinoids' Role in Modulating Central and Peripheral Immunity in Neurodegenerative Diseases. Int J Mol Sci 2024; 25:6402. [PMID: 38928109 PMCID: PMC11204381 DOI: 10.3390/ijms25126402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Revised: 05/30/2024] [Accepted: 06/05/2024] [Indexed: 06/28/2024] Open
Abstract
Cannabinoids (the endocannabinoids, the synthetic cannabinoids, and the phytocannabinoids) are well known for their various pharmacological properties, including neuroprotective and anti-inflammatory features, which are fundamentally important for the treatment of neurodegenerative diseases. The aging of the global population is causing an increase in these diseases that require the development of effective drugs to be even more urgent. Taking into account the unavailability of effective drugs for neurodegenerative diseases, it seems appropriate to consider the role of cannabinoids in the treatment of these diseases. To our knowledge, few reviews are devoted to cannabinoids' impact on modulating central and peripheral immunity in neurodegenerative diseases. The objective of this review is to provide the best possible information about the cannabinoid receptors and immuno-modulation features, peripheral immune modulation by cannabinoids, cannabinoid-based therapies for the treatment of neurological disorders, and the future development prospects of making cannabinoids versatile tools in the pursuit of effective drugs.
Collapse
Affiliation(s)
| | | | | | | | - Shimon Ben-Shabat
- Department of Clinical Biochemistry and Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel; (N.S.); (L.Y.); (B.K.); (S.F.-B.)
| |
Collapse
|
5
|
Esmaeili A, Ebrahimpour S, Hefshejani KF, Esmaeili A. Molecular mechanisms underlying the effect of tooth shortening on memory dysfunction in Wistar male rat. Arch Oral Biol 2024; 159:105878. [PMID: 38171058 DOI: 10.1016/j.archoralbio.2023.105878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 12/15/2023] [Accepted: 12/27/2023] [Indexed: 01/05/2024]
Abstract
OBJECTIVE We investigated the effects of molar tooth shortening on the mRNA expression of the AβPP/BACE1, BDNF/TrkB, and Bax/Bcl-2 signaling pathways in the Wistar male rat hippocampal regions. DESIGN Four groups (n = 5 per group) of male Wistar rats (control, SRM (shortened right molar), SLM (shortened left molar), and SBM (shortened bilateral molar)) were used. RNA was isolated from the hippocampus and transformed into cDNA. Real-time quantitative PCR was used to evaluate the mRNA expression levels of AβPP, BACE1, Bax, Bcl-2, BDNF, and TrkB. RESULTS Differential mRNA expression was observed in rat groups. SBM significantly upregulated the AβPP, BACE1, and Bax mRNA expressions, whereas the expression levels of Bcl-2, BDNF, and TrkB were decreased. SRM and SLM approximately had the same effect on the expression enhancement of AβPP, BACE1, and Bax; however, SRM was more effective than SLM in increasing the expression of these genes. CONCLUSIONS Symmetrical molar teeth shortening affected the mRNA expression of AβPP and BACE1, which is related to learning and memory dysfunction.
Collapse
Affiliation(s)
- Ali Esmaeili
- Dental Materials Research Center, Dental Research Institute, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Shiva Ebrahimpour
- Department of Cell and Molecular Biology & Microbiology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan, Iran
| | | | - Abolghasem Esmaeili
- Department of Cell and Molecular Biology & Microbiology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan, Iran.
| |
Collapse
|
6
|
Li R, Wang J, Xiong W, Luo Y, Feng H, Zhou H, Peng Y, He Y, Ye Q. The oral-brain axis: can periodontal pathogens trigger the onset and progression of Alzheimer's disease? Front Microbiol 2024; 15:1358179. [PMID: 38362505 PMCID: PMC10868393 DOI: 10.3389/fmicb.2024.1358179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 01/18/2024] [Indexed: 02/17/2024] Open
Abstract
Alzheimer's disease (AD) is the most prevalent form of dementia, characterized by a progressive cognitive decline. Sporadic AD, accounting for more than 95% of cases, may arise due to the influence of environmental factors. It was reported that periodontitis, a common oral ailment, shares several risk factors with AD, including advanced age, smoking, diabetes, and hypertension, among others. Periodontitis is an inflammatory disease triggered by dysbiosis of oral microorganisms, whereas Alzheimer's disease is characterized by neuroinflammation. Many studies have indicated that chronic inflammation can instigate brain AD-related pathologies, including amyloid-β plaques, Tau protein hyperphosphorylation, neuroinflammation, and neurodegeneration. The potential involvement of periodontal pathogens and/or their virulence factors in the onset and progression of AD by the oral-brain axis has garnered significant attention among researchers with ongoing investigations. This review has updated the periodontal pathogens potentially associated with AD, elucidating their impact on the central nervous system, immune response, and related pathological processes in the brain to provide valuable insights for future research on the oral-brain axis.
Collapse
Affiliation(s)
- Ruohan Li
- Center of Regenerative Medicine, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Junnan Wang
- Center of Regenerative Medicine, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Wei Xiong
- Center of Regenerative Medicine, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Yu Luo
- Center of Regenerative Medicine, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
- Department of Stomatology, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Huixian Feng
- Department of Stomatology, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Heng Zhou
- Center of Regenerative Medicine, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Youjian Peng
- Department of Stomatology, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| | - Yan He
- Institute of Regenerative and Translational Medicine, Tianyou Hospital, Wuhan University of Science and Technology, Wuhan, China
| | - Qingsong Ye
- Center of Regenerative Medicine, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
- Department of Stomatology, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China
| |
Collapse
|
7
|
Li Z, Wang H, Yin Y. Peripheral inflammation is a potential etiological factor in Alzheimer's disease. Rev Neurosci 2024; 35:99-120. [PMID: 37602685 DOI: 10.1515/revneuro-2023-0049] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 07/27/2023] [Indexed: 08/22/2023]
Abstract
Peripheral inflammation could constitute a risk factor for AD. This review summarizes the research related to peripheral inflammation that appears to have a relationship with Alzheimer's disease. We find there are significant associations between AD and peripheral infection induced by various pathogens, including herpes simplex virus type 1, cytomegalovirus, Epstein-Barr virus, human immunodeficiency virus, severe acute respiratory syndrome coronavirus 2, Porphyromonas gingivalis, Helicobacter pylori, and Toxoplasma gondii. Chronic inflammatory diseases are also reported to contribute to the pathophysiology of AD. The mechanisms by which peripheral inflammation affects the pathophysiology of AD are complex. Pathogen-derived neurotoxic molecule composition, disrupted BBB, and dysfunctional neurogenesis may all play a role in peripheral inflammation, promoting the development of AD. Anti-pathogenic medications and anti-inflammatory treatments are reported to decrease the risk of AD. Studies that could improve understanding the associations between AD and peripheral inflammation are needed. If our assumption is correct, early intervention against inflammation may be a potential method of preventing and treating AD.
Collapse
Affiliation(s)
- Ziyuan Li
- Department of Nuclear Medicine, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Kongjiang Road 1665, Yangpu District, Shanghai 200092, China
| | - Hui Wang
- Department of Nuclear Medicine, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Kongjiang Road 1665, Yangpu District, Shanghai 200092, China
| | - Yafu Yin
- Department of Nuclear Medicine, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Kongjiang Road 1665, Yangpu District, Shanghai 200092, China
| |
Collapse
|
8
|
Khuda F, Baharin B, Anuar NNM, Satimin BSF, Nasruddin NS. Effective Modalities of Periodontitis Induction in Rat Model. J Vet Dent 2024; 41:49-57. [PMID: 37259505 DOI: 10.1177/08987564231178459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Induction of periodontal disease using the rat model is the preferred model for human periodontal disease studies that are related to gene expression, mechanisms of inflammatory regulation, microbial and host responses, resolution, and the healing process. There are 3 methods that are frequently used to induce periodontal disease, which are: ligature application, oral bacterial inoculation, and the lipopolysaccharide injection technique. In the ligature model, sterile non-absorbable sutures or orthodontic wires are widely used to induce local irritation and bacterial plaque accumulation. Secondly, mono and mixed cultures of periodontal bacteria are inoculated orally by gavage or topical application. Lastly, lipopolysaccharide extracted from pathogenic bacteria can be directly injected into the gingival sulcus to induce inflammation and stimulate osteoclastogenesis and alveolar bone loss. Among these methods, ligature application induces inflammation and alveolar bone resorption more promptly compared to other methods. This review will provide an overview of the main induction methods in experimental periodontal disease, with their advantages and disadvantages.
Collapse
Affiliation(s)
- Fazle Khuda
- Department of Craniofacial Diagnostics and Biosciences, Faculty of Dentistry, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Badiah Baharin
- Faculty of Health Sciences, Programme of Biomedical Science, Centre for Toxicology and Health Risk Studies, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Nur Najmi Mohamad Anuar
- Department of Restorative Dentistry, Faculty of Dentistry, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | | | - Nurrul Shaqinah Nasruddin
- Department of Craniofacial Diagnostics and Biosciences, Faculty of Dentistry, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| |
Collapse
|
9
|
Carballo Á, López-Dequidt I, Custodia A, Botelho J, Aramburu-Núñez M, Machado V, Pías-Peleteiro JM, Ouro A, Romaus-Sanjurjo D, Vázquez-Vázquez L, Jiménez-Martín I, Aguiar P, Rodríguez-Yáñez M, Aldrey JM, Blanco J, Castillo J, Sobrino T, Leira Y. Association of periodontitis with cognitive decline and its progression: Contribution of blood-based biomarkers of Alzheimer's disease to this relationship. J Clin Periodontol 2023; 50:1444-1454. [PMID: 37584311 DOI: 10.1111/jcpe.13861] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 07/12/2023] [Accepted: 07/26/2023] [Indexed: 08/17/2023]
Abstract
AIM To assess whether periodontitis is associated with cognitive decline and its progression as well as with certain blood-based markers of Alzheimer's disease. MATERIALS AND METHODS Data from a 2-year follow-up prospective cohort study (n = 101) was analysed. Participants with a previous history of hypertension and aged ≥60 years were included in the analysis. All of them received a full-mouth periodontal examination and cognitive function assessments (Addenbrooke's Cognitive Examination (ACE) and Mini-Mental State Examination [MMSE]). Plasma levels of amyloid beta (Aβ)1-40 , Aβ1-42 , phosphorylated and total Tau (p-Tau and t-Tau) were determined at baseline, 12 and 24 months. RESULTS Periodontitis was associated with poor cognitive performance (MMSE: β = -1.5 [0.6]) and progression of cognitive impairment (hazard ratio [HR] = 1.8; 95% confidence interval: 1.0-3.1). Subjects with periodontitis showed greater baseline levels of p-Tau (1.6 [0.7] vs. 1.2 [0.2] pg/mL, p < .001) and Aβ1-40 (242.1 [77.3] vs. 208.2 [73.8] pg/mL, p = .036) compared with those without periodontitis. Concentrations of the latter protein also increased over time only in the periodontitis group (p = .005). CONCLUSIONS Periodontitis is associated with cognitive decline and its progression in elderly patients with a previous history of hypertension. Overexpression of p-Tau and Aβ1-40 may play a role in this association.
Collapse
Affiliation(s)
- Álvaro Carballo
- Periodontology Unit, Faculty of Odontology and Medicine, University of Santiago de Compostela, Santiago de Compostela, Spain
| | - Iria López-Dequidt
- Stroke Unit, Neurology Department, University Clinical Hospital, Santiago de Compostela, Spain
| | - Antía Custodia
- NeuroAging Laboratory Group (NEURAL), Clinical Neurosciences Research Laboratories (LINC), Health Research Institute of Santiago de Compostela (IDIS), University Clinical Hospital, Santiago de Compostela, Spain
- Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Madrid, Spain
| | - João Botelho
- Periodontology Department and Evidence-Based Hub, Clinical Research Unit, Centro de Investigação Interdisciplinar Egas Moniz, Instituto Universitário Egas Moniz - Cooperativa de Ensino Superior, Caparica, Portugal
| | - Marta Aramburu-Núñez
- NeuroAging Laboratory Group (NEURAL), Clinical Neurosciences Research Laboratories (LINC), Health Research Institute of Santiago de Compostela (IDIS), University Clinical Hospital, Santiago de Compostela, Spain
- Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Madrid, Spain
| | - Vanessa Machado
- Periodontology Department and Evidence-Based Hub, Clinical Research Unit, Centro de Investigação Interdisciplinar Egas Moniz, Instituto Universitário Egas Moniz - Cooperativa de Ensino Superior, Caparica, Portugal
| | - Juan Manuel Pías-Peleteiro
- NeuroAging Laboratory Group (NEURAL), Clinical Neurosciences Research Laboratories (LINC), Health Research Institute of Santiago de Compostela (IDIS), University Clinical Hospital, Santiago de Compostela, Spain
- Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Madrid, Spain
- Dementia Unit, Neurology Department, University Clinical Hospital, Santiago de Compostela, Spain
| | - Alberto Ouro
- NeuroAging Laboratory Group (NEURAL), Clinical Neurosciences Research Laboratories (LINC), Health Research Institute of Santiago de Compostela (IDIS), University Clinical Hospital, Santiago de Compostela, Spain
- Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Madrid, Spain
| | - Daniel Romaus-Sanjurjo
- NeuroAging Laboratory Group (NEURAL), Clinical Neurosciences Research Laboratories (LINC), Health Research Institute of Santiago de Compostela (IDIS), University Clinical Hospital, Santiago de Compostela, Spain
- Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Madrid, Spain
| | - Laura Vázquez-Vázquez
- NeuroAging Laboratory Group (NEURAL), Clinical Neurosciences Research Laboratories (LINC), Health Research Institute of Santiago de Compostela (IDIS), University Clinical Hospital, Santiago de Compostela, Spain
- Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Madrid, Spain
| | - Isabel Jiménez-Martín
- Dementia Unit, Neurology Department, University Clinical Hospital, Santiago de Compostela, Spain
| | - Pablo Aguiar
- Molecular Imaging Group, Department of Radiology, Faculty of Medicine and Center for Research In Molecular Medicine and Chronic Diseases (CIMUS), University of Santiago de Compostela, Santiago de Compostela, Spain
- Nuclear Medicine Department and Molecular Imaging Group, University Clinical Hospital, Santiago de Compostela, Spain
| | - Manuel Rodríguez-Yáñez
- Stroke Unit, Neurology Department, University Clinical Hospital, Santiago de Compostela, Spain
| | - José Manuel Aldrey
- NeuroAging Laboratory Group (NEURAL), Clinical Neurosciences Research Laboratories (LINC), Health Research Institute of Santiago de Compostela (IDIS), University Clinical Hospital, Santiago de Compostela, Spain
- Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Madrid, Spain
- Dementia Unit, Neurology Department, University Clinical Hospital, Santiago de Compostela, Spain
| | - Juan Blanco
- Periodontology Unit, Faculty of Odontology and Medicine, University of Santiago de Compostela, Santiago de Compostela, Spain
| | - José Castillo
- Neuroimaging and Biotechnology Laboratory (NOBEL) Group, Clinical Neurosciences Research Laboratories (LINC), Health Research Institute of Santiago de Compostela (IDIS), University Clinical Hospital, Santiago de Compostela, Spain
| | - Tomás Sobrino
- NeuroAging Laboratory Group (NEURAL), Clinical Neurosciences Research Laboratories (LINC), Health Research Institute of Santiago de Compostela (IDIS), University Clinical Hospital, Santiago de Compostela, Spain
- Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Madrid, Spain
| | - Yago Leira
- Periodontology Unit, Faculty of Odontology and Medicine, University of Santiago de Compostela, Santiago de Compostela, Spain
- NeuroAging Laboratory Group (NEURAL), Clinical Neurosciences Research Laboratories (LINC), Health Research Institute of Santiago de Compostela (IDIS), University Clinical Hospital, Santiago de Compostela, Spain
- Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Madrid, Spain
| |
Collapse
|
10
|
Zhou X, Kumar P, Bhuyan DJ, Jensen SO, Roberts TL, Münch GW. Neuroinflammation in Alzheimer's Disease: A Potential Role of Nose-Picking in Pathogen Entry via the Olfactory System? Biomolecules 2023; 13:1568. [PMID: 38002250 PMCID: PMC10669446 DOI: 10.3390/biom13111568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 10/22/2023] [Accepted: 10/23/2023] [Indexed: 11/26/2023] Open
Abstract
Alzheimer's disease (AD) is a complex neurodegenerative disorder characterized by progressive cognitive decline and memory impairment. Many possible factors might contribute to the development of AD, including amyloid peptide and tau deposition, but more recent evidence suggests that neuroinflammation may also play an-at least partial-role in its pathogenesis. In recent years, emerging research has explored the possible involvement of external, invading pathogens in starting or accelerating the neuroinflammatory processes in AD. In this narrative review, we advance the hypothesis that neuroinflammation in AD might be partially caused by viral, bacterial, and fungal pathogens entering the brain through the nose and the olfactory system. The olfactory system represents a plausible route for pathogen entry, given its direct anatomical connection to the brain and its involvement in the early stages of AD. We discuss the potential mechanisms through which pathogens may exploit the olfactory pathway to initiate neuroinflammation, one of them being accidental exposure of the olfactory mucosa to hands contaminated with soil and feces when picking one's nose.
Collapse
Affiliation(s)
- Xian Zhou
- NICM Health Research Institute, Western Sydney University, Westmead, NSW 2145, Australia; (X.Z.); (D.J.B.)
| | - Paayal Kumar
- Pharmacology Unit, School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia;
| | - Deep J. Bhuyan
- NICM Health Research Institute, Western Sydney University, Westmead, NSW 2145, Australia; (X.Z.); (D.J.B.)
| | - Slade O. Jensen
- Ingham Institute for Applied Medical Research, Liverpool, NSW 2170, Australia; (S.O.J.); (T.L.R.)
- Microbiology and Infectious Diseases Unit, School of Medicine, Western Sydney University, Liverpool, NSW 2170, Australia
| | - Tara L. Roberts
- Ingham Institute for Applied Medical Research, Liverpool, NSW 2170, Australia; (S.O.J.); (T.L.R.)
- Oncology Unit, School of Medicine, Western Sydney University, Liverpool, NSW 2170, Australia
| | - Gerald W. Münch
- NICM Health Research Institute, Western Sydney University, Westmead, NSW 2145, Australia; (X.Z.); (D.J.B.)
- Pharmacology Unit, School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia;
| |
Collapse
|
11
|
Ferrà-Cañellas MDM, Munar-Bestard M, Floris I, Ramis JM, Monjo M, Garcia-Sureda L. A Sequential Micro-Immunotherapy Medicine Increases Collagen Deposition in Human Gingival Fibroblasts and in an Engineered 3D Gingival Model under Inflammatory Conditions. Int J Mol Sci 2023; 24:10484. [PMID: 37445663 DOI: 10.3390/ijms241310484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 06/06/2023] [Accepted: 06/16/2023] [Indexed: 07/15/2023] Open
Abstract
Periodontal therapies use immune mediators, but their side effects can increase with dosage. Micro-immunotherapy (MI) is a promising alternative that employs immune regulators at low and ultralow doses to minimize adverse effects. In this study, the effects of 5 capsules and the entire 10-capsule sequence of the sequential MI medicine (MIM-seq) were tested in two in vitro models of periodontitis. Firstly, human gingival fibroblasts (hGFs) exposed to interleukin (IL)-1β to induce inflammation were treated with five different capsules of MIM-seq for 3 days or with MIM-seq for 24 days. Subsequently, MIM-seq was analyzed in a 3D model of human tissue equivalent of gingiva (GTE) under the same inflammatory stimulus. Simultaneously, a non-IL-1β-treated control and a vehicle were included. The effects of the treatments on cytotoxicity, collagen deposition, and the secreted levels of IL-1α, IL-6, prostaglandin E2 (PGE2), matrix metalloproteinase-1 (MMP-1), and tissue inhibitor of metalloproteinases-1 (TIMP-1) were evaluated. None of the tested items were cytotoxic. The complete sequence of MIM-seq decreased PGE2 release and restored collagen deposition levels induced by IL-1β treatment in hGFs exposed to IL-1β. MIM-seq treatment restored collagen production levels in both models. These promising preclinical findings suggest that MIM-seq should be further investigated for periodontitis treatment.
Collapse
Affiliation(s)
- Maria Del Mar Ferrà-Cañellas
- Group of Cell Therapy and Tissue Engineering, Research Institute on Health Sciences (IUNICS), University of the Balearic Islands, 07122 Palma de Mallorca, Spain
- Preclinical Research Department, Labo'Life España, 07330 Consell, Spain
- Balearic Islands Health Research Institute (IdISBa), 07122 Palma de Mallorca, Spain
| | - Marta Munar-Bestard
- Group of Cell Therapy and Tissue Engineering, Research Institute on Health Sciences (IUNICS), University of the Balearic Islands, 07122 Palma de Mallorca, Spain
- Balearic Islands Health Research Institute (IdISBa), 07122 Palma de Mallorca, Spain
| | - Ilaria Floris
- Preclinical Research Department, Labo'Life France, 44000 Nantes, France
| | - Joana Maria Ramis
- Group of Cell Therapy and Tissue Engineering, Research Institute on Health Sciences (IUNICS), University of the Balearic Islands, 07122 Palma de Mallorca, Spain
- Balearic Islands Health Research Institute (IdISBa), 07122 Palma de Mallorca, Spain
| | - Marta Monjo
- Group of Cell Therapy and Tissue Engineering, Research Institute on Health Sciences (IUNICS), University of the Balearic Islands, 07122 Palma de Mallorca, Spain
- Balearic Islands Health Research Institute (IdISBa), 07122 Palma de Mallorca, Spain
| | | |
Collapse
|
12
|
Li Y, Guan X, He Y, Jia X, Pan L, Wang Y, Han Y, Zhao R, Yang J, Hou T. ProBDNF signaling is involved in periodontitis-induced depression-like behavior in mouse hippocampus. Int Immunopharmacol 2023; 116:109767. [PMID: 36738676 DOI: 10.1016/j.intimp.2023.109767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 01/15/2023] [Accepted: 01/19/2023] [Indexed: 02/05/2023]
Abstract
OBJECTIVE Increasing evidence supports the association between periodontitis and depression. However, the specific mechanisms remain to be further elucidated. The present study aimed to mechanistically investigate the regional roles of proBDNF (the precursor of brain-derived neurotrophic factor) in periodontitis induced depression-like behavior in mice. METHODS Experimental periodontitis model was established by periodontal injection of Porphyromonas gingivalis lipopolysaccharide (Pg-LPS) in 8-week-old male Bdnf-HA/HA mice for 3 weeks. The depression-like behaviors, spontaneous exploratory activity and the level of anxiety were assessed by behavior tests. The activation of microglia and astrocytes, as well as the expression of Interleukin (IL)-1β and Tumor necrosis factor (TNF)-α in the hippocampus, prefrontal cortex, and cortex were further assessed by immunofluorescence and western blots. The levels of IL-1β in blood serum and expression of occludin as well as claudin5 in the hippocampus, prefrontal cortex, and cortex were further determined by enzyme-linked immunosorbent assay and western blot. Finally, the expression of proBDNF, its receptors, and mature BDNF (mBDNF), as well as neuronal activity were measured by western blots and immunofluorescence. RESULTS Pg-LPS successfully induced periodontitis in mice and caused obvious depression-like behavior. Furthermore, we observed an increased activation of astrocytes and microglia, as well as a significant increase in expression of IL-1β and TNF-α in the hippocampus of mice treated with Pg-LPS, with elevated level of IL-1β in serum and decreased expression of occludin and claudin5 in the hippocampus. Importantly, we found that the levels of proBDNF and its receptors, SorCS2 and p75NTR, were increased significantly; however, the level of mBDNF was decreased, therefor leading to greater ratio of proBDNF/mBDNF. In addition, we also detected decreased neuronal activity in the hippocampus of mice treated with Pg-LPS. CONCLUSIONS Our results indicate that Pg-LPS-induced periodontitis could cause depression-like behaviors in mice, and the proBDNF signaling is involved in the process.
Collapse
Affiliation(s)
- Yingxue Li
- Key laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China; Department of Cariology and Endodontics, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China
| | - Xiaoyue Guan
- Key laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China; Department of Cariology and Endodontics, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China
| | - Yani He
- Key laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China; Department of Cariology and Endodontics, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China
| | - Xiangbin Jia
- Key laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China; Department of Cariology and Endodontics, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China
| | - Lifei Pan
- Key laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China; Department of Cariology and Endodontics, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China
| | - Yuting Wang
- Key laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China; Department of Cariology and Endodontics, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China
| | - Yue Han
- Key laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China; Department of Cariology and Endodontics, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China
| | - Rui Zhao
- Key laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China; Department of Cariology and Endodontics, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China
| | - Jianmin Yang
- Department of Medicine, Weill Cornell Medical School, Cornell University, New York, NY 10065, USA.
| | - Tiezhou Hou
- Key laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China; Department of Cariology and Endodontics, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China.
| |
Collapse
|
13
|
Salhi L, Al Taep Y, Salmon E, Van Hede D, Lambert F. How Periodontitis or Periodontal Bacteria Can Influence Alzheimer's Disease Features? A Systematic Review of Pre-Clinical Studies. J Alzheimers Dis 2023; 96:979-1010. [PMID: 37927257 PMCID: PMC10741373 DOI: 10.3233/jad-230478] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/14/2023] [Indexed: 11/07/2023]
Abstract
BACKGROUND The negative effects of periodontitis on systemic diseases, including diabetes, cardiovascular diseases, and Alzheimer's disease (AD), have been widely described. OBJECTIVE This systematic review aimed to gather the current understanding of the pathophysiological mechanisms linking periodontitis to AD. METHODS An electronic systematic search of the PubMed/MEDLINE, Scopus, and Embase databases was performed using the following PECO question: How can periodontitis or periodontal bacteria influence Alzheimer's disease features?". Only preclinical studies exploring the biological links between periodontitis and AD pathology were included. This study was registered at the International Prospective Register of Systematic Reviews (PROSPERO), and the Syrcle and Camarades protocols were used to assess the risk of bias. RESULTS After a systematic screening of titles and abstracts (n = 3,307), thirty-six titles were selected for abstract reading, of which 13 were excluded (k = 1), resulting in the inclusion of 23 articles. Oral or systemic exposure to periodontopathogens or their byproducts is responsible for both in situ brain manifestations and systemic effects. Significant elevated rates of cytokines and amyloid peptides (Aβ) and derivate products were found in both serum and brain. Additionally, in infected animals, hyperphosphorylation of tau protein, hippocampal microgliosis, and neuronal death were observed. Exposure to periodontal infection negatively impairs cognitive behavior, leading to memory decline. CONCLUSIONS Systemic inflammation and brain metastatic infections induced by periodontal pathogens contribute to neuroinflammation, amyloidosis, and tau phosphorylation, leading to brain damage and subsequent cognitive impairment.
Collapse
Affiliation(s)
- Leila Salhi
- Department of Periodontology, Oro-Dental and Implant Surgery, University Hospital of Liège, Liège, Belgium
| | - Yaman Al Taep
- Department of Periodontology, Oro-Dental and Implant Surgery, University Hospital of Liège, Liège, Belgium
| | - Eric Salmon
- Department of Neurology - Memory Clinic, University Hospital of Liège, Liège, Belgium
- GIGA Cyclotron Research Center, University of Liege, Liege, Belgium
| | - Dorien Van Hede
- Department of Periodontology, Oro-Dental and Implant Surgery, University Hospital of Liège, Liège, Belgium
| | - France Lambert
- Department of Periodontology, Oro-Dental and Implant Surgery, University Hospital of Liège, Liège, Belgium
| |
Collapse
|
14
|
Ai R, Li D, Shi L, Zhang X, Ding Z, Zhu Y, He Y. Periodontitis induced by orthodontic wire ligature drives oral microflora dysbiosis and aggravates alveolar bone loss in an improved murine model. Front Microbiol 2022; 13:875091. [PMID: 36160195 PMCID: PMC9493320 DOI: 10.3389/fmicb.2022.875091] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Accepted: 07/29/2022] [Indexed: 12/02/2022] Open
Abstract
Aim To assess the contribution of polymicrobial disruption of host homeostasis to periodontitis progression in orthodontic wire ligation murine model. Methods Orthodontic wire rings were inserted between the first and second molars of mice for 18 days for the orthodontic wire ligation mouse model, and Pg injection model and Pg-LPS injection model were used as controls. Alveolar bone loss and periodontal inflammation were analyzed by micro-CT, histological staining and qRT-PCR. Further, pyrosequencing of 16S rRNA gene amplicon was used to analyze the development of oral microorganism dysbiosis in the mice. Results Micro-CT, TRAP staining and qRT-PCR showed that orthodontic wire ligation model led to more severe alveolar bone loss than Pg and Pg-LPS models. H&E staining and qRT-PCR demonstrated that stronger inflammatory response was induced by the orthodontic wire treatment compared to the other models. In addition, pyrosequencing of 16S rRNA gene amplicons revealed that the composition of oral microbiota presented a transition as the disease progressed and significant differences emerged in oral microbiota communities between orthodontic ligature mice and healthy controls. Furthermore, antibiotic treatment decreased both inflammation and alveolar bone loss in response to microbial community dysbiosis. However, no significant difference in bacterial community composition was observed in Pg and Pg-LPS models. Conclusions Orthodontic wire ligation drove oral microbial community transitions that mimicked polymicrobial communities characterized by polymicrobial synergy and dysbiosis. Our improved model is suitable for further study of pathogenesis of periodontitis and exploration of corresponding treatment strategies.
Collapse
Affiliation(s)
- Rongshuang Ai
- Key Laboratory of Diagnostic Medicine (Ministry of Education), Department of Laboratory Medicine, Chongqing Medical University, Chongqing, China
| | - Dingyi Li
- Key Laboratory of Diagnostic Medicine (Ministry of Education), Department of Laboratory Medicine, Chongqing Medical University, Chongqing, China
| | - Luyao Shi
- Key Laboratory of Diagnostic Medicine (Ministry of Education), Department of Laboratory Medicine, Chongqing Medical University, Chongqing, China
| | - Xiaonan Zhang
- College of Stomatology, Chongqing Medical University, Chongqing, China
| | - Zhiqiang Ding
- School of Computer Science, Chongqing Institute of Engineering, Chongqing, China
| | - Yiting Zhu
- Key Laboratory of Diagnostic Medicine (Ministry of Education), Department of Laboratory Medicine, Chongqing Medical University, Chongqing, China
- Department of Laboratory Medicine, Chongqing University Three Gorges Hospital, Chongqing, China
| | - Yujuan He
- Key Laboratory of Diagnostic Medicine (Ministry of Education), Department of Laboratory Medicine, Chongqing Medical University, Chongqing, China
- *Correspondence: Yujuan He
| |
Collapse
|
15
|
Chen JL, Tong Y, Zhu Q, Gao LQ, Sun Y. Neutrophil extracellular traps induced by Porphyromonas gingivalis lipopolysaccharide modulate inflammatory responses via a Ca2+-dependent pathway. Arch Oral Biol 2022; 141:105467. [DOI: 10.1016/j.archoralbio.2022.105467] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 05/26/2022] [Accepted: 05/27/2022] [Indexed: 12/27/2022]
|
16
|
Harding A, Kanagasingam S, Welbury R, Singhrao SK. Periodontitis as a Risk Factor for Alzheimer's Disease: The Experimental Journey So Far, with Hope of Therapy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1373:241-260. [PMID: 35612802 DOI: 10.1007/978-3-030-96881-6_13] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Periodontitis and Alzheimer's disease (AD) exist globally within the adult population. Given that the risk of AD incidence doubles within 10 years from the time of periodontal disease diagnosis, there is a window of opportunity for slowing down or preventing AD by risk-reduction-based intervention. Literature appraisal on the shared risk factors of these diseases suggests a shift to a healthy lifestyle would be beneficial. Generalised (chronic) periodontitis with an established dysbiotic polymicrobial aetiology affects the tooth supporting tissues with eventual tooth loss. The cause of AD remains unknown, however two neurohistopathological lesions - amyloid-beta plaques and neurofibrillary tangles, together with the clinical history, provide AD diagnosis at autopsy. Historically, prominence was given to the two hallmark lesions but now emphasis is placed on cerebral inflammation and what triggers it. Low socioeconomic status promotes poor lifestyles that compromise oral and personal hygiene along with reliance on poor dietary intake. Taken together with advancing age and a declining immune protection, these risk factors may negatively impact on periodontitis and AD. These factors also provide a tangible solution to controlling pathogenic bacteria indigenous to the oral and gastrointestinal tract microbioes in vulnerable subjects. The focus here is on Porphyromonas gingivalis, one of several important bacterial pathogens associated with both periodontitis and AD. Recent research has enabled advances in our knowledge of the armoury of P. gingivalis via reproduction of all clinical and neuropathological hallmark lesions of AD and chronic periodontal disease in vitro and in vivo experimental models, thus paving the way for better future management.
Collapse
Affiliation(s)
- Alice Harding
- Brain and Behavior Centre, Faculty of Clinical and Biomedical Sciences, School of Dentistry, University of Central Lancashire, Preston, UK
| | - Shalini Kanagasingam
- Brain and Behavior Centre, Faculty of Clinical and Biomedical Sciences, School of Dentistry, University of Central Lancashire, Preston, UK
| | - 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.
| |
Collapse
|
17
|
Abstract
The potential contribution of pathogenic microbes to dementia-inducing disease is a subject of considerable importance. Alzheimer’s disease (AD) is a neurocognitive disease that slowly destroys brain function, leading to cognitive decline and behavioral and psychiatric disorders. The histopathology of AD is associated with neuronal loss and progressive synaptic dysfunction, accompanied by the deposition of amyloid-β (Aβ) peptide in the form of parenchymal plaques and abnormal aggregated tau protein in the form of neurofibrillary tangles. Observational, epidemiological, experimental, and pathological studies have generated evidence for the complexity and possible polymicrobial causality in dementia-inducing diseases. The AD pathogen hypothesis states that pathogens and microbes act as triggers, interacting with genetic factors to initiate the accumulation of Aβ, hyperphosphorylated tau protein (p-tau), and inflammation in the brain. Evidence indicates that Borrelia sp., HSV-1, VZV (HHV-2), HHV-6/7, oral pathogens, Chlamydophila pneumoniae, and Candida albicans can infect the central nervous system (CNS), evade the immune system, and consequently prevail in the AD brain. Researchers have made significant progress in understanding the multifactorial and overlapping factors that are thought to take part in the etiopathogenesis of dementia; however, the cause of AD remains unclear.
Collapse
|
18
|
Park DY, Park JY, Lee D, Hwang I, Kim HS. Leaky Gum: The Revisited Origin of Systemic Diseases. Cells 2022; 11:1079. [PMID: 35406643 PMCID: PMC8997512 DOI: 10.3390/cells11071079] [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] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 03/21/2022] [Accepted: 03/22/2022] [Indexed: 12/10/2022] Open
Abstract
The oral cavity is the gateway for microorganisms into your body where they disseminate not only to the directly connected respiratory and digestive tracts but also to the many remote organs. Oral microbiota, travelling to the end of the intestine and circulating in our bodies through blood vessels, not only affect a gut microbiome profile but also lead to many systemic diseases. By gathering information accumulated from the era of focal infection theory to the age of revolution in microbiome research, we propose a pivotal role of "leaky gum", as an analogy of "leaky gut", to underscore the importance of the oral cavity in systemic health. The oral cavity has unique structures, the gingival sulcus (GS) and the junctional epithelium (JE) below the GS, which are rarely found anywhere else in our body. The JE is attached to the tooth enamel and cementum by hemidesmosome (HD), which is structurally weaker than desmosome and is, thus, vulnerable to microbial infiltration. In the GS, microbial biofilms can build up for life, unlike the biofilms on the skin and intestinal mucosa that fall off by the natural process. Thus, we emphasize that the GS and the JE are the weakest leaky point for microbes to invade the human body, making the leaky gum just as important as, or even more important than, the leaky gut.
Collapse
Affiliation(s)
- Do-Young Park
- DOCSmedi Co., Ltd., 4F, 143, Gangseong-ro, Ilsanseo-gu, Goyang-si 10387, Korea;
| | - Jin Young Park
- Department of Gastrointestinal Endoscopy, Apple Tree Healthcare Center, 1450, Jungang-ro, Ilsanseo-gu, Goyang-si 10387, Korea;
| | - Dahye Lee
- Department of Orthodontics, Apple Tree Dental Hospital, 1450, Jungang-ro, Ilsanseo-gu, Goyang-si 10387, Korea;
- Apple Tree Institute of Biomedical Science, Apple Tree Medical Foundation, 1450, Jungang-ro, Ilsanseo-gu, Goyang-si 10387, Korea
| | - Inseong Hwang
- DOCSmedi Co., Ltd., 4F, 143, Gangseong-ro, Ilsanseo-gu, Goyang-si 10387, Korea;
| | - Hye-Sung Kim
- Department of Orthodontics, Apple Tree Dental Hospital, 1450, Jungang-ro, Ilsanseo-gu, Goyang-si 10387, Korea;
- Apple Tree Institute of Biomedical Science, Apple Tree Medical Foundation, 1450, Jungang-ro, Ilsanseo-gu, Goyang-si 10387, Korea
| |
Collapse
|
19
|
Yang Y, Ren D, Zhao D, Zhang B, Ye R. MicroRNA-203 mediates P. gingivalis LPS-induced inflammation and differentiation of periodontal ligament cells. Oral Dis 2022; 29:1715-1725. [PMID: 35034420 DOI: 10.1111/odi.14132] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 12/07/2021] [Accepted: 01/09/2022] [Indexed: 02/05/2023]
Abstract
AIM In this study, we aimed to explore the effects of microRNA-203 (miR-203) on P. gingivalis lipopolysaccharide (P.g. LPS)-stimulated periodontal ligament cells (PDLCs) and identify potential molecular targets for periodontitis treatment. METHODS PDLCs were stimulated by P.g. LPS, followed by quantification of miR-203 and AP-1 expression. Next, loss- and gain-of-function experiments were applied in P.g. LPS-induced PDLCs. The proliferation, apoptosis, and differentiation of PDLCs were determined and mineralized nodule numbers were counted. Functional assays were used to identify interactions among miR-203, activator protein 1 (AP-1), and intercellular adhesion molecule 1 (ICAM-1). In addition, expression of osteogenesis-related genes and release of proinflammatory factors were analyzed. RESULTS miR-203 was found to be downregulated while AP-1 was upregulated in PDLCs stimulated by P.g. LPS. The overexpression of miR-203 promoted P.g. LPS-stimulated PDLC proliferation and differentiation, inhibited apoptosis, and increased the number of mineralized nodules. miR-203 was verified to downregulate AP-1/ICAM-1 axis. miR-203 overexpression reduced the secretion of proinflammatory factors while increasing expression of osteogenesis-related genes in P.g. LPS-stimulated PDLCs, which was reversed by overexpressing AP-1 and ICAM-1. CONCLUSION These experimental data demonstrated the potential inhibitory effects of overexpressed miR-203 on periodontitis development by promoting PDLC differentiation and suppressing inflammatory responses through AP-1/ICAM-1 axis.
Collapse
Affiliation(s)
- Yang Yang
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, 610041, Sichuan, China.,Department of General Dentistry, West China Hospital of Stomatology, Sichuan University, 610041, Sichuan, China
| | - Dongping Ren
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, 610041, Sichuan, China.,Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, 610041, Sichuan, China
| | - Duo Zhao
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, 610041, Sichuan, China.,Department of General Dentistry, West China Hospital of Stomatology, Sichuan University, 610041, Sichuan, China
| | - Bo Zhang
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, 610041, Sichuan, China.,Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, 610041, Sichuan, China
| | - Rui Ye
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, 610041, Sichuan, China.,Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, 610041, Sichuan, China
| |
Collapse
|
20
|
Olsen I. Porphyromonas gingivalis-Induced Neuroinflammation in Alzheimer's Disease. Front Neurosci 2021; 15:691016. [PMID: 34720846 PMCID: PMC8551391 DOI: 10.3389/fnins.2021.691016] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 08/27/2021] [Indexed: 11/13/2022] Open
Abstract
"Chronic" periodontitis and its keystone pathogen Porphyromonas gingivalis have repeatedly been associated with Alzheimer's disease (AD). Pathological hallmarks in AD are brain accumulations of amyloid-beta and neurofibrillary tangles consisting of aggregated and hyperphosphorylated tau. In addition, neuroinflammation induced by P. gingivalis has increasingly been recognized as a factor in the pathogenesis of AD. The present mini-review discusses possible mechanisms for the induction of neuroinflammation by P. gingivalis in AD, involving factors such as pro-inflammatory mediators, amyloid-beta, tau, microglia, cathepsin B, and protein kinase R. Inflammagens of P. gingivalis such as lipopolysaccharide and gingipains are also discussed.
Collapse
Affiliation(s)
- Ingar Olsen
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
| |
Collapse
|
21
|
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.
Collapse
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
| |
Collapse
|
22
|
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.
Collapse
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
| |
Collapse
|
23
|
Sugawara S, Ishikawa T, Sato S, Kihara H, Taira M, Sasaki M, Kondo H. Uptake of Nanotitania by Gingival Epithelial Cells Promotes Inflammatory Response and Is Accelerated by Porphyromonas gingivalis Lipopolysaccharide: An In Vitro Study. Int J Mol Sci 2021; 22:ijms22158084. [PMID: 34360848 PMCID: PMC8348964 DOI: 10.3390/ijms22158084] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 07/26/2021] [Accepted: 07/26/2021] [Indexed: 12/28/2022] Open
Abstract
Titanium is often used in the medical field and in dental implants due to its biocompatibility, but it has a high rate of leading to peri-implantitis, which progresses faster than periodontitis. Therefore, in the present study, the expression of cytokines from gingival epithelial cells by nanotitania was investigated, which is derived from titanium in the oral cavity, and the additional effect of Porphyromonasgingivalis (periodontopathic bacteria) lipopolysaccharide (PgLPS) was investigated. Ca9-22 cells were used as a gingival epithelial cell model and were cultured with nanotitania alone or with PgLPS. Cytokine expression was examined by reverse transcription-quantitative polymerase chain reaction and enzyme-linked immunosorbent assay. In addition, cellular uptake of nanotitania was observed in scanning electron microscopy images. The expression of interleukin (IL)-6 and IL-8 significantly increased in Ca9-22 cells by nanotitania treatment alone, and the expression was further increased by the presence of PgLPS. Nanotitania was observed to phagocytose Ca9-22 cells in a dose- and time-dependent manner. Furthermore, when the expression of IL-11, related to bone resorption, was investigated, a significant increase was confirmed by stimulation with nanotitania alone. Therefore, nanotitania could be associated with the onset and exacerbation of peri-implantitis, and the presence of periodontal pathogens may worsen the condition. Further clinical reports are needed to confirm these preliminary results.
Collapse
Affiliation(s)
- Shiho Sugawara
- Department of Prosthodontics and Oral Implantology, School of Dentistry, Iwate Medical University, 1-3-27 Chuo-dori, Morioka 020-8505, Iwate, Japan; (S.S.); (H.K.); (H.K.)
| | - Taichi Ishikawa
- Division of Molecular Microbiology, Department of Microbiology, Iwate Medical University, 1-1-1 Idai-dori, Morioka 028-3694, Iwate, Japan;
- Correspondence: ; Fax: +81-19-908-8011
| | - Shu Sato
- Division of Dental Anesthesiology, Department of Reconstructive Oral and Maxillofacial Surgery, School of Dentistry, Iwate Medical University, 1-3-27 Chuo-dori, Morioka 020-8505, Iwate, Japan;
| | - Hidemichi Kihara
- Department of Prosthodontics and Oral Implantology, School of Dentistry, Iwate Medical University, 1-3-27 Chuo-dori, Morioka 020-8505, Iwate, Japan; (S.S.); (H.K.); (H.K.)
| | - Masayuki Taira
- Department of Biomedical Engineering, Iwate Medical University, 1-1-1 Idai-dori, Morioka 028-3694, Iwate, Japan;
| | - Minoru Sasaki
- Division of Molecular Microbiology, Department of Microbiology, Iwate Medical University, 1-1-1 Idai-dori, Morioka 028-3694, Iwate, Japan;
| | - Hisatomo Kondo
- Department of Prosthodontics and Oral Implantology, School of Dentistry, Iwate Medical University, 1-3-27 Chuo-dori, Morioka 020-8505, Iwate, Japan; (S.S.); (H.K.); (H.K.)
| |
Collapse
|
24
|
Lin Y, Wang Y, Lin J, Xie Y. Research on Autophagy of Gingiva Epithelial Cell Induced by Porphyromonas Gingivalis Regulated by Long Non-Coding RNA Transforming Growth Factor Beta-2 Overlapping Transcript 1 (LncRNA TGFB2-OT1). J BIOMATER TISS ENG 2021. [DOI: 10.1166/jbt.2021.2686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Our study analyzes lncRNA TGFB2-OT1’s effect on autophagy and migration of gingiva epithelial cells and porphyromonas gingivalis. The expression of TGFB2-OT1 and TIMP2 in GEC cells was detected by QRT-PCR. Cell proliferation and colon formation was assessed by MTT method and colony
forming assay. The relation between TGFB2-OT1 and TIMP2 was confirmed luciferase assay. The autophagy, apoptosis rate and period distribution was detected by flow cytometry along with analysis of porphyromonas gingivalis of GEC cells. TGFB2-OT1 was upregulated significantly as shown by IncRNA
array. TGFB2-OT1 overexpression in GEC cells improved cell proliferation and migration, enhanced the sensibility of gingiva epithelial cell on the porphyromonas gingivalis and increased autophagy. The GEC cells were blocked at G2/M period. The TIMP2 was a direct target of TGFB2-OT1. In conclusion,
TIMP2 participates in the up-regulation of MMP10 induced by TGFB2-OT1. The lncRNA TGFB2-OT1 maybe be a potential biomarker to assess the autophagy of gingiva epithelial cell.
Collapse
Affiliation(s)
- Yujiao Lin
- Department of Stomatology, Shantou Central Hospital (Affiliated Shantou Hospital of Sun Yat-Sen University), Shantou, Guangdong, 515031, China
| | - Youshan Wang
- Department of Stomatology, Shantou Central Hospital (Affiliated Shantou Hospital of Sun Yat-Sen University), Shantou, Guangdong, 515031, China
| | - Jiaxu Lin
- Department of Stomatology, Shantou Central Hospital (Affiliated Shantou Hospital of Sun Yat-Sen University), Shantou, Guangdong, 515031, China
| | - Yiwen Xie
- Department of Stomatology, Shantou Central Hospital (Affiliated Shantou Hospital of Sun Yat-Sen University), Shantou, Guangdong, 515031, China
| |
Collapse
|
25
|
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.
Collapse
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
| |
Collapse
|
26
|
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.
Collapse
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
| |
Collapse
|
27
|
Olsen I, Singhrao SK. Porphyromonas gingivalis infection may contribute to systemic and intracerebral amyloid-beta: implications for Alzheimer's disease onset. Expert Rev Anti Infect Ther 2020; 18:1063-1066. [PMID: 32663042 DOI: 10.1080/14787210.2020.1792292] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Ingar Olsen
- Department of Oral Biology, Faculty of Dentistry, University of Oslo , Oslo, Norway
| | - Sim K Singhrao
- Brain and Behavior Centre, Faculty of Clinical and Biomedical Sciences, School of Dentistry, University of Central Lancashire , Preston, UK
| |
Collapse
|
28
|
Leira Y, Iglesias-Rey R, Gómez-Lado N, Aguiar P, Sobrino T, D'Aiuto F, Castillo J, Blanco J, Campos F. Periodontitis and vascular inflammatory biomarkers: an experimental in vivo study in rats. Odontology 2020; 108:202-212. [PMID: 31583485 PMCID: PMC7066291 DOI: 10.1007/s10266-019-00461-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 08/13/2019] [Indexed: 11/12/2022]
Abstract
The objective of this preclinical in vivo study was to determine changes in vascular inflammatory biomarkers in systemic circulation after injection of lipopolysaccharide (LPS) from Porphyromonas gingivalis (Pg) in rats. Experimental periodontitis was induced by injections of Pg-LPS. Gingival soft and hard tissues changes were analysed by means of magnetic resonance imaging and micro computed tomography. Serum levels of interleukin (IL)-6, IL-10, pentraxin (PTX) 3, and soluble fragment of tumor necrosis factor-like weak inducer of apoptosis (sTWEAK) were determined at baseline and 24 h, 7, 14, and 21 days after periodontal induction. Significant periodontal inflammation and alveolar bone loss were evident at the end of periodontal induction. Experimental periodontitis posed an acute systemic inflammatory response with increased serum levels of IL-6 and PTX3 at 24 h post-induction, followed by a significant overexpression of sTWEAK at 7 days. This inflammatory state was maintained until the end of the experiment (21 days). As expected, IL-10 serum levels were significantly lower during the follow-up compared to baseline concentrations. In the present animal model, experimental periodontitis is associated with increased systemic inflammation. Further studies are needed to confirm whether PTX3 and sTWEAK could be useful biomarkers to investigate potential mechanisms underlying the relationship between periodontitis and atherosclerotic vascular diseases.
Collapse
Affiliation(s)
- Yago Leira
- Periodontology Unit, Faculty of Medicine and Odontology, University of Santiago de Compostela, Medical-Surgical Dentistry (OMEQUI) Research Group, Health Research Institute of Santiago de Compostela (IDIS), Santiago de Compostela, Spain.
- Periodontology Unit, UCL Eastman Dental Institute and Hospital, University College London, 256 Gray's Inn Road, London, WC1X 8LD, UK.
| | - Ramón Iglesias-Rey
- Clinical Neurosciences Research Laboratory, Clinical University Hospital, Health Research Institute of Santiago de Compostela (IDIS), Travesa da Choupana s/n, 15706, Santiago de Compostela, Spain
| | - Noemí Gómez-Lado
- Molecular Imaging Group, Clinical University Hospital, Faculty of Medicine, University of Santiago de Compostela, Health Research Institute of Santiago de Compostela (IDIS), Santiago de Compostela, Spain
| | - Pablo Aguiar
- Molecular Imaging Group, Clinical University Hospital, Faculty of Medicine, University of Santiago de Compostela, Health Research Institute of Santiago de Compostela (IDIS), Santiago de Compostela, Spain
| | - Tomás Sobrino
- Clinical Neurosciences Research Laboratory, Clinical University Hospital, Health Research Institute of Santiago de Compostela (IDIS), Travesa da Choupana s/n, 15706, Santiago de Compostela, Spain
| | - Francesco D'Aiuto
- Periodontology Unit, UCL Eastman Dental Institute and Hospital, University College London, 256 Gray's Inn Road, London, WC1X 8LD, UK
| | - José Castillo
- Clinical Neurosciences Research Laboratory, Clinical University Hospital, Health Research Institute of Santiago de Compostela (IDIS), Travesa da Choupana s/n, 15706, Santiago de Compostela, Spain
| | - Juan Blanco
- Periodontology Unit, Faculty of Medicine and Odontology, University of Santiago de Compostela, Medical-Surgical Dentistry (OMEQUI) Research Group, Health Research Institute of Santiago de Compostela (IDIS), Santiago de Compostela, Spain
| | - Francisco Campos
- Clinical Neurosciences Research Laboratory, Clinical University Hospital, Health Research Institute of Santiago de Compostela (IDIS), Travesa da Choupana s/n, 15706, Santiago de Compostela, Spain.
| |
Collapse
|
29
|
Leira Y, Carballo Á, Orlandi M, Aldrey JM, Pías‐Peleteiro JM, Moreno F, Vázquez‐Vázquez L, Campos F, D’Aiuto F, Castillo J, Sobrino T, Blanco J. Periodontitis and systemic markers of neurodegeneration: A case–control study. J Clin Periodontol 2020; 47:561-571. [DOI: 10.1111/jcpe.13267] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 12/28/2019] [Accepted: 02/03/2020] [Indexed: 01/08/2023]
Affiliation(s)
- Yago Leira
- Periodontology Unit UCL Eastman Dental Institute and NIHR UCLH Biomedical Research Centre University College London London UK
- Periodontology Unit Faculty of Medicine and Odontology University of Santiago de Compostela Santiago de Compostela Spain
- Medical‐Surgical Dentistry (OMEQUI) Research Group Health Research Institute of Santiago de Compostela (IDIS) Santiago de Compostela Spain
| | - Álvaro Carballo
- Periodontology Unit Faculty of Medicine and Odontology University of Santiago de Compostela Santiago de Compostela Spain
| | - Marco Orlandi
- Periodontology Unit UCL Eastman Dental Institute and NIHR UCLH Biomedical Research Centre University College London London UK
| | - José Manuel Aldrey
- Dementia Unit Department of Neurology Clinical University Hospital Santiago de Compostela Spain
- Clinical Neurosciences Research Laboratory Health Research Institute of Santiago de Compostela (IDIS) Santiago de Compostela Spain
| | - Juan Manuel Pías‐Peleteiro
- Dementia Unit Department of Neurology Clinical University Hospital Santiago de Compostela Spain
- Clinical Neurosciences Research Laboratory Health Research Institute of Santiago de Compostela (IDIS) Santiago de Compostela Spain
| | - Federico Moreno
- Periodontology Unit UCL Eastman Dental Institute and NIHR UCLH Biomedical Research Centre University College London London UK
| | - Laura Vázquez‐Vázquez
- Dementia Unit Department of Neurology Clinical University Hospital Santiago de Compostela Spain
- Clinical Neurosciences Research Laboratory Health Research Institute of Santiago de Compostela (IDIS) Santiago de Compostela Spain
| | - Francisco Campos
- Clinical Neurosciences Research Laboratory Health Research Institute of Santiago de Compostela (IDIS) Santiago de Compostela Spain
| | - Francesco D’Aiuto
- Periodontology Unit UCL Eastman Dental Institute and NIHR UCLH Biomedical Research Centre University College London London UK
| | - José Castillo
- Clinical Neurosciences Research Laboratory Health Research Institute of Santiago de Compostela (IDIS) Santiago de Compostela Spain
| | - Tomás Sobrino
- Clinical Neurosciences Research Laboratory Health Research Institute of Santiago de Compostela (IDIS) Santiago de Compostela Spain
| | - Juan Blanco
- Periodontology Unit Faculty of Medicine and Odontology University of Santiago de Compostela Santiago de Compostela Spain
- Medical‐Surgical Dentistry (OMEQUI) Research Group Health Research Institute of Santiago de Compostela (IDIS) Santiago de Compostela Spain
| |
Collapse
|
30
|
Wu X, Zhang G, Feng X, Li P, Tan Y. Transcriptome analysis of human periodontal ligament fibroblasts exposed to Porphyromonas gingivalis LPS. Arch Oral Biol 2020; 110:104632. [DOI: 10.1016/j.archoralbio.2019.104632] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 11/09/2019] [Accepted: 12/03/2019] [Indexed: 12/28/2022]
|
31
|
Gu Y, Wu Z, Zeng F, Jiang M, Teeling JL, Ni J, Takahashi I. Systemic Exposure to Lipopolysaccharide from Porphyromonas gingivalis Induces Bone Loss-Correlated Alzheimer's Disease-Like Pathologies in Middle-Aged Mice. J Alzheimers Dis 2020; 78:61-74. [PMID: 32925065 DOI: 10.3233/jad-200689] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Alzheimer's disease (AD) and bone loss are clinically exacerbated. However, the mechanism of exacerbation remains understood. OBJECTIVE We tested our hypothesis that periodontitis is involved in the exacerbation, contributing to AD pathologies. METHODS The bone, memory, and inflammation in bone and brain were examined in 12-month-old mice after systemic exposure to lipopolysaccharide from Porphyromonas gingivalis (P gLPS) for 3 consecutive weeks. RESULTS Compared with control mice, bone loss in tibia (26% decrease) and memory decline (47% decrease) were induced in mice with a positive correlation after exposure to P gLPS (r = 0.7378, p = 0.0011). The IL-6 and IL-17 expression in tibia was negatively correlated with the bone volume/total tissue volume (r = -0.6619, p = 0.0052; r = -0.7129, p = 0.0019), while that in the cortex was negatively correlated with the memory test latency (r = -0.7198, p = 0.0017; p = 0.0351, r = -0.5291). Furthermore, the IL-17 expression in microglia was positively correlated with Aβ42 accumulation in neurons (r = 0.8635, p < 0.0001). In cultured MG6 microglia, the P gLPS-increased IL-6 expression was inhibited by a PI3K-specific inhibitor (68% decrease), and that of IL-17 was inhibited by IL-6 antibody (41% decrease). In cultured N2a neurons, conditioned medium from P gLPS-stimulated microglia (MCM) but not P gLPS increased the productions of AβPP, CatB, and Aβ42, which were significantly inhibited by pre-treatment with IL-17 antibody (67%, 51%, and 41% decrease). CONCLUSION These findings demonstrated that chronic systemic exposure to P gLPS simultaneously induces inflammation-dependent bone loss and AD-like pathologies by elevating IL-6 and IL-17 from middle age, suggesting that periodontal bacteria induce exacerbation of bone loss and memory decline, resulting in AD progression.
Collapse
Affiliation(s)
- Yebo Gu
- Section of Orthodontics and Dentofacial Orthopedics, Division of Oral Health, Growth and Development, Faculty of Dental Science, Kyushu University, Fukuoka, Japan
| | - Zhou Wu
- Department of Aging Science and Pharmacology, Faculty of Dental Sciences, Kyushu University, Fukuoka, Japan
- OBT Research Center, Faculty of Dental Science, Kyushu University, Fukuoka, Japan
| | - Fan Zeng
- Department of Aging Science and Pharmacology, Faculty of Dental Sciences, Kyushu University, Fukuoka, Japan
| | - Muzhou Jiang
- Department of Aging Science and Pharmacology, Faculty of Dental Sciences, Kyushu University, Fukuoka, Japan
| | - Jessica L Teeling
- Biological Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, United Kingdom
| | - Junjun Ni
- Department of Aging Science and Pharmacology, Faculty of Dental Sciences, Kyushu University, Fukuoka, Japan
- Key Laboratory of Molecular Medicine, Department of Biology, School of Life Science, Beijing Institute of Technology, Beijing, China
| | - Ichiro Takahashi
- Section of Orthodontics and Dentofacial Orthopedics, Division of Oral Health, Growth and Development, Faculty of Dental Science, Kyushu University, Fukuoka, Japan
| |
Collapse
|
32
|
Khan J, Puchimada B, Kadouri D, Zusman T, Javed F, Eliav E. The anti-nociceptive effects of Porphyromonas gingivalis lipopolysaccharide. Arch Oral Biol 2019; 102:193-198. [PMID: 31071639 DOI: 10.1016/j.archoralbio.2019.04.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 04/15/2019] [Accepted: 04/19/2019] [Indexed: 10/26/2022]
Abstract
OBJECTIVE The objective of this study was to assess the effect of Porphyromonas gingivalis lipopolysaccharide (PG LPS) on acute pain-related behaviour induced in rats and to measure its impact on the levels of pro-inflammatory cytokines (IL-1β, IL-6) and anti-inflammatory (IL-10) cytokines. DESIGN The Brennan model was used to induce acute pain like signs in rats' hind paw. Twenty-four hours following the surgery the rats were divided into 5 groups and the affected paws were injected with 0.2 m l of one of three commercialized forms PG LPS doses (high - 1 mg/ml, medium - 0.6 mg/m l and low - 0.2 mg/m l), diclofenac sodium (1 mg/kg) or saline. Tactile allodynia, mechanical hyperalgesia, body temperature and paw swelling were assessed at baseline, 24 h postoperatively and 2 h after the paw injection. The affected and contra-lateral paw tissue was assessed for the mentioned above cytokines levels employing enzyme-linked immunosorbent assay. RESULTS This study may suggest that PG LPS can reduce pain like behaviour via increased levels of anti-inflammatory cytokine IL-10 (5900 ± 748, p < 0.05). The high PG LPS dose and diclofenac reduced the tactile allodynia and mechanical hyperalgesia significantly (42.2 ± 4 and1.6 ± 0.3, p < 0.05). PG LPS high dose increase IL-10 levels while diclofenac reduces IL-1β levels significantly (5900 ± 748 and 1760 ± 271.2). The LPS administration had no effect on paw swelling and did not increase rat's body temperature. CONCLUSION The results demonstrated that PG LPS local application could possess anti- nociceptive properties, which at least in part is mediated by an increase in IL-10 levels.
Collapse
Affiliation(s)
- Junad Khan
- Orofacial Pain and Temporomandibular Joint Disorders, Eastman Institute for Oral Health, University of Rochester, 625 Elmwood Avenue, Rochester, NY, 14620, USA.
| | - Bollama Puchimada
- Department of Diagnostic Sciences, Rutgers School of Dental Medicine, NJ, USA
| | - Daniel Kadouri
- Oral Biology, Rutgers School of Dental Medicine, NJ, USA
| | - Tali Zusman
- Department of Diagnostic Sciences, Rutgers School of Dental Medicine, NJ, USA
| | - Fawad Javed
- Department of Periodontology, Stony Brook University, Stony Brook, NY, USA; Laboratory for Periodontal-, Implant-, Phototherapy (LA-PIP), School of Dental Medicine, Stony Brook University, Stony Brook, NY, USA
| | - Eli Eliav
- Eastman Institute for Oral Health, University of Rochester, NY, USA
| |
Collapse
|