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Verma A, Azhar G, Patyal P, Zhang W, Zhang X, Wei JY. Proteomic analysis of P. gingivalis-Lipopolysaccharide induced neuroinflammation in SH-SY5Y and HMC3 cells. GeroScience 2024; 46:4315-4332. [PMID: 38507186 PMCID: PMC11336124 DOI: 10.1007/s11357-024-01117-z] [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: 01/10/2024] [Accepted: 02/26/2024] [Indexed: 03/22/2024] Open
Abstract
Chronic periodontitis and its keystone pathogen, Porphyromonas gingivalis, have increasingly been linked with Alzheimer's disease (AD). However, P.gingivalis-lipopolysaccharide (LPS) mediated release of neuroinflammatory proteins contributes to AD remains underexplored. In this study, we utilized data-independent acquisition mass spectrometry to characterize P.gingivalis-LPS induced profile of differentially expressed proteins associated with the neuroinflammatory response in human neuroblastoma (SH-SY5Y) and human microglial (HMC3) cells. We reported a set of 124 proteins in SH-SY5Y cells and 96 proteins in HMC3 cells whose levels were significantly upregulated or downregulated by exposure to P. gingivalis-LPS. Our findings demonstrate that P. gingivalis-LPS contributed to the elevated expressions of dementia biomarkers and pro-inflammatory cytokines that include APP, Aβ1-42, Aβ1-40, T-Tau, p-Tau, VEGF, TGF-β, IL-1β, IL-6 and TNF-α through 2 distinct pathways of extracellular sensing by cell surface receptors and intracellular cytosolic receptors. Interestingly, intracellular signaling proteins activated with P. gingivalis-LPS transfection using Lipofectamine™ 2000 had significantly higher fold change protein expression compared to the extracellular signaling with P. gingivalis-LPS treatment. Additionally, we also explored P. gingivalis-LPS mediated activation of caspase-4 dependent non canonical inflammasome pathway in both SH-SY5Y and HMC3 cells. In summary, P. gingivalis-LPS induced neuroinflammatory protein expression in SH-SY5Y and HMC3 cells, provided insights into the specific inflammatory pathways underlying the potential link between P. gingivalis-LPS infection and the pathogenesis of Alzheimer's disease and related dementias.
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Affiliation(s)
- Ambika Verma
- Department of Geriatrics, Donald W. Reynolds Institute On Aging, University of Arkansas for Medical Sciences, 4301 West Markham, Little Rock, AR, 72205, USA
| | - Gohar Azhar
- Department of Geriatrics, Donald W. Reynolds Institute On Aging, University of Arkansas for Medical Sciences, 4301 West Markham, Little Rock, AR, 72205, USA
| | - Pankaj Patyal
- Department of Geriatrics, Donald W. Reynolds Institute On Aging, University of Arkansas for Medical Sciences, 4301 West Markham, Little Rock, AR, 72205, USA
| | - Wei Zhang
- Department of Mathematics and Statistics, University of Arkansas at Little Rock, Little Rock, AR, USA
| | - Xiaomin Zhang
- Department of Geriatrics, Donald W. Reynolds Institute On Aging, University of Arkansas for Medical Sciences, 4301 West Markham, Little Rock, AR, 72205, USA
| | - Jeanne Y Wei
- Department of Geriatrics, Donald W. Reynolds Institute On Aging, University of Arkansas for Medical Sciences, 4301 West Markham, Little Rock, AR, 72205, USA.
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Dibello V, Custodero C, Cavalcanti R, Lafornara D, Dibello A, Lozupone M, Daniele A, Pilotto A, Panza F, Solfrizzi V. Impact of periodontal disease on cognitive disorders, dementia, and depression: a systematic review and meta-analysis. GeroScience 2024; 46:5133-5169. [PMID: 38943006 PMCID: PMC11336026 DOI: 10.1007/s11357-024-01243-8] [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: 02/21/2024] [Accepted: 06/05/2024] [Indexed: 06/30/2024] Open
Abstract
A growing body of research suggested that there was a link between poor periodontal health and systemic diseases, particularly with the early development of cognitive disorders, dementia, and depression. This is especially true in cases of changes in diet, malnutrition, loss of muscular endurance, and abnormal systemic inflammatory response. Our study aimed to determine the extent of these associations to better target the multi-level healthy aging challenge investigating the impact of periodontal disease on cognitive disorders (cognitive impairment and cognitive decline), dementia, and depression. We conducted a comprehensive literature search up to November 2023 using six different electronic databases. Two independent researchers assessed the eligibility of 7363 records against the inclusion criteria and found only 46 records that met the requirements. The study is registered on PROSPERO (CRD42023485688). We generated random effects pooled estimates and 95% confidence intervals (CI) to evaluate whether periodontal disease increased the risk of the investigated outcomes. The quality assessment revealed moderate quality of evidence and risk of bias. Periodontal disease was found to be associated with both cognitive disorders (relative risk (RR) 1.25, 95% CI 1.11-1.40, in the analysis of cross-sectional studies); cognitive impairment (RR 3.01, 95% CI 1.52-5.95 for longitudinal studies, cognitive decline); and dementia (RR 1.22, 95% CI 1.10-1.36). However, no significant increased risk of depression among subjects with periodontal disease was found (RR 1.07, 95% CI 0.95-1.21). Despite the association with two of the three explored outcomes, the available evidence on periodontal diseases and dementia, cognitive disorders, and depression is controversial due to several limitations. Therefore, further investigations involving validated and standardized tools are required.
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Affiliation(s)
- Vittorio Dibello
- Department of Orofacial Pain and Dysfunction, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
- Cesare Frugoni" Internal and Geriatric Medicine and Memory Unit, University of Bari "Aldo Moro", Bari, Italy
| | - Carlo Custodero
- Cesare Frugoni" Internal and Geriatric Medicine and Memory Unit, University of Bari "Aldo Moro", Bari, Italy
| | - Raffaele Cavalcanti
- Department of General Surgery and Surgical-Medical Specialties, University of Catania, Catania, Italy
| | - Domenico Lafornara
- Division of Diagnostic Imaging, Department of Surgical and Biomedical Sciences, Santa Maria della Misericordia Hospital, University of Perugia, Perugia, Italy
| | - Antonio Dibello
- Stella Maris Nursing Home and Day Care Center, Monopoli, Bari, Italy
| | - Madia Lozupone
- Department of Translational Biomedicine & Neuroscience 'DiBraiN', University of Bari Aldo Moro, Bari, Italy
| | - Antonio Daniele
- Department of Neuroscience, Catholic University of Sacred Heart, Rome, Italy
- Neurology Unit, IRCCS Fondazione Policlinico Universitario A. Gemelli, Rome, Italy
| | - Alberto Pilotto
- Cesare Frugoni" Internal and Geriatric Medicine and Memory Unit, University of Bari "Aldo Moro", Bari, Italy
- Geriatrics Unit, Department of Geriatric Care, Orthogeriatrics and Rehabilitation, Galliera Hospital, Genoa, Italy
| | - Francesco Panza
- Cesare Frugoni" Internal and Geriatric Medicine and Memory Unit, University of Bari "Aldo Moro", Bari, Italy.
| | - Vincenzo Solfrizzi
- Cesare Frugoni" Internal and Geriatric Medicine and Memory Unit, University of Bari "Aldo Moro", Bari, Italy
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Chen X, Dai Y, Li Y, Xin J, Zou J, Wang R, Zhang H, Liu Z. Identification of cross-talk pathways and PANoptosis-related genes in periodontitis and Alzheimer's disease by bioinformatics analysis and machine learning. Front Aging Neurosci 2024; 16:1430290. [PMID: 39258145 PMCID: PMC11384588 DOI: 10.3389/fnagi.2024.1430290] [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: 05/09/2024] [Accepted: 08/08/2024] [Indexed: 09/12/2024] Open
Abstract
Background and objectives Periodontitis (PD), a chronic inflammatory disease, is a serious threat to oral health and is one of the risk factors for Alzheimer's disease (AD). A growing body of evidence suggests that the two diseases are closely related. However, current studies have not provided a comprehensive understanding of the common genes and common mechanisms between PD and AD. This study aimed to screen the crosstalk genes of PD and AD and the potential relationship between cross-talk and PANoptosis-related genes. The relationship between core genes and immune cells will be analyzed to provide new targets for clinical treatment. Materials and methods The PD and AD datasets were downloaded from the GEO database and differential expression analysis was performed to obtain DEGs. Overlapping DEGs had cross-talk genes linking PD and OP, and PANoptosis-related genes were obtained from a literature review. Pearson coefficients were used to compute cross-talk and PANoptosis-related gene correlations in the PD and AD datasets. Cross-talk genes were obtained from the intersection of PD and AD-related genes, protein-protein interaction(PPI) networks were constructed and cross-talk genes were identified using the STRING database. The intersection of cross-talk and PANoptosis-related genes was defined as cross-talk-PANoptosis genes. Core genes were screened using ROC analysis and XGBoost. PPI subnetwork, gene-biological process, and gene-pathway networks were constructed based on the core genes. In addition, immune infiltration on the PD and AD datasets was analyzed using the CIBERSORT algorithm. Results 366 cross-talk genes were overlapping between PD DEGs and AD DEGs. The intersection of cross-talk genes with 109 PANoptosis-related genes was defined as cross-talk-PANoptosis genes. ROC and XGBoost showed that MLKL, DCN, IL1B, and IL18 were more accurate than the other cross-talk-PANoptosis genes in predicting the disease, as well as better in overall characterization. GO and KEGG analyses showed that the four core genes were involved in immunity and inflammation in the organism. Immune infiltration analysis showed that B cells naive, Plasma cells, and T cells gamma delta were significantly differentially expressed in patients with PD and AD compared with the normal group. Finally, 10 drugs associated with core genes were retrieved from the DGIDB database. Conclusion This study reveals the joint mechanism between PD and AD associated with PANoptosis. Analyzing the four core genes and immune cells may provide new therapeutic directions for the pathogenesis of PD combined with AD.
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Affiliation(s)
- Xiantao Chen
- Hospital of Stomatology, Jilin University, Changchun, China
- Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling, Changchun, China
| | - Yifei Dai
- Hospital of Stomatology, Jilin University, Changchun, China
- Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling, Changchun, China
| | - Yushen Li
- Hospital of Stomatology, Jilin University, Changchun, China
- Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling, Changchun, China
| | - Jiajun Xin
- Hospital of Stomatology, Jilin University, Changchun, China
- Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling, Changchun, China
| | - Jiatong Zou
- Hospital of Stomatology, Jilin University, Changchun, China
- Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling, Changchun, China
| | - Rui Wang
- Hospital of Stomatology, Jilin University, Changchun, China
- Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling, Changchun, China
| | - Hao Zhang
- Hospital of Stomatology, Jilin University, Changchun, China
- Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling, Changchun, China
| | - Zhihui Liu
- Hospital of Stomatology, Jilin University, Changchun, China
- Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling, Changchun, China
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Leonov G, Salikhova D, Starodubova A, Vasilyev A, Makhnach O, Fatkhudinov T, Goldshtein D. Oral Microbiome Dysbiosis as a Risk Factor for Stroke: A Comprehensive Review. Microorganisms 2024; 12:1732. [PMID: 39203574 PMCID: PMC11357103 DOI: 10.3390/microorganisms12081732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2024] [Revised: 08/07/2024] [Accepted: 08/19/2024] [Indexed: 09/03/2024] Open
Abstract
Stroke represents a significant global health burden, with a substantial impact on mortality, morbidity, and long-term disability. The examination of stroke biomarkers, particularly the oral microbiome, offers a promising avenue for advancing our understanding of the factors that contribute to stroke risk and for developing strategies to mitigate that risk. This review highlights the significant correlations between oral diseases, such as periodontitis and caries, and the onset of stroke. Periodontal pathogens within the oral microbiome have been identified as a contributing factor in the exacerbation of risk factors for stroke, including obesity, dyslipidemia, atherosclerosis, hypertension, and endothelial dysfunction. The alteration of the oral microbiome may contribute to these conditions, emphasizing the vital role of oral health in the prevention of cardiovascular disease. The integration of dental and medical health practices represents a promising avenue for enhancing stroke prevention efforts and improving patient outcomes.
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Affiliation(s)
- Georgy Leonov
- Federal Research Center of Nutrition, Biotechnology and Food Safety, 109240 Moscow, Russia;
| | - Diana Salikhova
- Institute of Molecular and Cellular Medicine, RUDN University, 117198 Moscow, Russia; (D.S.); (A.V.); (T.F.)
- Research Centre for Medical Genetics, 115522 Moscow, Russia; (O.M.); (D.G.)
| | - Antonina Starodubova
- Federal Research Center of Nutrition, Biotechnology and Food Safety, 109240 Moscow, Russia;
- Therapy Faculty, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
| | - Andrey Vasilyev
- Institute of Molecular and Cellular Medicine, RUDN University, 117198 Moscow, Russia; (D.S.); (A.V.); (T.F.)
- Research Centre for Medical Genetics, 115522 Moscow, Russia; (O.M.); (D.G.)
- E.V. Borovsky Institute of Dentistry, I.M. Sechenov First Moscow State Medical University of the Ministry of Health of the Russian Federation (Sechenov University), 119991 Moscow, Russia
- Central Research Institute of Dental and Maxillofacial Surgery, 119021 Moscow, Russia
| | - Oleg Makhnach
- Research Centre for Medical Genetics, 115522 Moscow, Russia; (O.M.); (D.G.)
| | - Timur Fatkhudinov
- Institute of Molecular and Cellular Medicine, RUDN University, 117198 Moscow, Russia; (D.S.); (A.V.); (T.F.)
| | - Dmitry Goldshtein
- Research Centre for Medical Genetics, 115522 Moscow, Russia; (O.M.); (D.G.)
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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.
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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
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Muraoka K, Oda M, Yoshino K, Tanaka T, Morishita M, Nakamura T, Kibune R, Sonoki K, Morimoto Y, Nakashima K, Awano S. The potential positive effect of periodontal treatment on brain function activity using functional magnetic resonance imaging analysis. J Dent Sci 2024; 19:1811-1818. [PMID: 39035336 PMCID: PMC11259615 DOI: 10.1016/j.jds.2023.09.024] [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: 09/19/2023] [Revised: 09/21/2023] [Indexed: 07/23/2024] Open
Abstract
Background/purpose There are reports on the relationship between periodontal treatment and the whole body. The purpose of the present study was to investigate the effect of periodontal initial treatment on brain function activity by improving periodontal tissue and the occlusal status of subjects with periodontitis. Materials and methods The subjects were 13 patients with periodontitis. Following the patient's informed written consent, the periodontal initial treatment provided to the patient included tooth brushing instruction, scaling and root planning, however, occlusal adjustment was not performed at this stage. Periodontal examination, occlusal force examination and fMRI results were also evaluated at the initial and the reevaluation examinations. Results After the periodontal initial treatment had been performed, periodontal tissue had significantly improved. In addition, cerebral blood flow in the insula and primary motor cortex was also improved, as confirmed by fMRI. Conclusion This result suggests that the periodontal ligament has recovered and the periodontal ligament neuron have been further subjected to clenching in the insula.
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Affiliation(s)
- Kosuke Muraoka
- Division of Clinical Education Development and Research, Kyushu Dental University, Kitakyushu, Japan
| | - Masafumi Oda
- Division of Oral and Maxillofacial Radiology, Kyushu Dental University, Kitakyushu, Japan
| | - Kenichi Yoshino
- Section of Primary Dental Education, Kyushu Dental University, Kitakyushu, Japan
| | - Tatsurou Tanaka
- Graduate School of Medical and Dental Sciences, Department of Maxillofacial Radiology, Kagoshima University, Kagoshima, Japan
| | - Masaki Morishita
- Division of Clinical Education Development and Research, Kyushu Dental University, Kitakyushu, Japan
| | - Taiji Nakamura
- Division of Periodontology, Kyushu Dental University, Kitakyushu, Japan
| | - Ryota Kibune
- Division of Clinical Education Development and Research, Kyushu Dental University, Kitakyushu, Japan
| | - Kazuo Sonoki
- Unit of Interdisciplinary Education, School of Oral Health Science, Kyushu Dental University, Kitakyushu, Japan
| | - Yasuhiro Morimoto
- Division of Oral and Maxillofacial Radiology, Kyushu Dental University, Kitakyushu, Japan
| | - Keisuke Nakashima
- Division of Periodontology, Kyushu Dental University, Kitakyushu, Japan
| | - Shuji Awano
- Division of Clinical Education Development and Research, Kyushu Dental University, Kitakyushu, Japan
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Da Mesquita S, Rua R. Brain border-associated macrophages: common denominators in infection, aging, and Alzheimer's disease? Trends Immunol 2024; 45:346-357. [PMID: 38632001 PMCID: PMC11088519 DOI: 10.1016/j.it.2024.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 03/18/2024] [Accepted: 03/20/2024] [Indexed: 04/19/2024]
Abstract
Mammalian brain border-associated macrophages (BAMs) are strategically positioned to support vital properties and processes: for example, the composition of the brain's perivascular extracellular matrix and cerebrospinal fluid flow via the glymphatic pathway. BAMs also effectively restrict the spread of infectious microbes into the brain. However, while fighting infections, BAMs sustain long-term transcriptomic changes and can be replaced by inflammatory monocytes, potentially leading to a gradual loss of their beneficial homeostatic functions. We hypothesize that by expediting the deterioration of BAMs, multiple infection episodes might be associated with accelerated brain aging and the putative development of neurodegenerative diseases. Our viewpoint is supported by recent studies suggesting that rejuvenating aged BAMs, and counterbalancing their detrimental inflammatory signatures during infections, might hold promise in treating aging-related neurological disorders, including Alzheimer's disease (AD).
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Affiliation(s)
| | - Rejane Rua
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, Inserm, CNRS, Marseille, France.
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Hashim N, Babiker R, Mohammed R, Chaitanya NC, Rahman MM, Gismalla B. Highlighting the Effect of Pro-inflammatory Mediators in the Pathogenesis of Periodontal Diseases and Alzheimer's Disease. JOURNAL OF PHARMACY AND BIOALLIED SCIENCES 2024; 16:S1120-S1128. [PMID: 38882732 PMCID: PMC11174192 DOI: 10.4103/jpbs.jpbs_1120_23] [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: 10/28/2023] [Revised: 11/25/2023] [Accepted: 12/06/2023] [Indexed: 06/18/2024] Open
Abstract
Alzheimer's disease (AD) is a neurological condition that is much more common as people get older. It may start out early or late. Increased levels of pro-inflammatory cytokines and microglial activation, both of which contribute to the central nervous system's inflammatory state, are characteristics of AD. As opposed to this, periodontitis is a widespread oral infection brought on by Gram-negative anaerobic bacteria. By releasing pro-inflammatory cytokines into the systemic circulation, periodontitis can be classified as a "low-grade systemic disease." Periodontitis and AD are linked by inflammation, which is recognized to play a crucial part in both the disease processes. The current review sought to highlight the effects of pro-inflammatory cytokines, which are released during periodontal and Alzheimer's diseases in the pathophysiology of both conditions. It also addresses the puzzling relationship between AD and periodontitis, highlighting the etiology and potential ramifications.
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Affiliation(s)
- Nada Hashim
- Periodontology, RAK College of Dental Sciences, RAK Medical and Health Sciences University, Ras al-Khaimah, UAE
| | - Rasha Babiker
- Physiology, RAK College of Medical Sciences, RAK Medical and Health Sciences University, Ras al-Khaimah, UAE
| | - Riham Mohammed
- Oral and Maxillofacial Surgery, RAK College of Dental Sciences, RAK Medical and Health Sciences University, Ras al-Khaimah, UAE
| | - Nallan Csk Chaitanya
- Oral Medicine and Radiology, RAK College of Dental Sciences, RAK Medical and Health Sciences University, Ras al-Khaimah, UAE
| | - Muhammed M Rahman
- Periodontology, RAK College of Dental Sciences, RAK Medical and Health Sciences University, Ras al-Khaimah, UAE
| | - Bakri Gismalla
- Periodontology, Faculty of Dentistry, University of Khartoum, Khartoum, Sudan
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9
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Shen H, Jiang Y, Qiu C, Xie X, Zhang H, He Z, Song Z, Zhou W. Abnormal amyloid precursor protein processing in periodontal tissue in a murine model of periodontitis induced by Porphyromonas gingivalis. J Periodontal Res 2024; 59:395-407. [PMID: 38311599 DOI: 10.1111/jre.13224] [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: 01/30/2023] [Revised: 11/27/2023] [Accepted: 12/05/2023] [Indexed: 02/06/2024]
Abstract
OBJECTIVE The study aimed to investigate the change of amyloid precursor protein (APP) processing and amyloid β (Aβ) metabolites in linking periodontitis to Alzheimer's disease (AD). BACKGROUND Aβ is one of the main pathological features of AD, and few studies have discussed changes in its expression in peripheral tissues or analyzed the relationship between the peripheral imbalance of Aβ production and clearance. METHODS A murine model of periodontitis was established by oral infection with Porphyromonas gingivalis (P. gingivalis). Micro-computed tomography (Micro-CT) was used to observe the destruction of the alveolar bone. Nested quantitative polymerase chain reaction (qPCR) was used to measure small quantities of P.gingivalis DNA in different tissues. Behavioral experiments were performed to measure cognitive function in the mice. The mRNA levels of TNF-α, IL-6, IL-8, RANKL, OPG, APP695, APP751, APP770, and BACE1 in the gingival tissues or cortex were detected by RT-PCR. The levels of Aβ1-40 and Aβ1-42 in gingival crevicular fluid (GCF) and plasma were tested by ELISA. RESULTS P. gingivalis oral infection was found to cause alveolar bone resorption and impaired learning and memory. P.gingivalis DNA was detected in the gingiva, blood and cortex of the P.gingivalis group by nested qPCR (p < .05). The mRNA expression of TNF-α, IL-6, IL-8, RANKL/OPG, and BACE1 in the gingival tissue was significantly higher than that in the control group (p < .05). Similarly, upregulated mRNA levels of APP695 and APP770 were observed in the gingival tissuses and cortex of the P. gingivalis group (p < .05). The levels of Aβ1-40 and Aβ1-42 in the GCF and plasma of the P. gingivalis group were significantly higher than those in the control group (p < .05). CONCLUSION P. gingivalis can directly invade the brain via hematogenous infection. The invasion of P. gingivalis could trigger an immune response and lead to an imbalance between Aβ production and clearance in peripheral tissues, which may trigger an abnormal Aβ metabolite in the brain, resulting in the occurrence and development of AD.
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Affiliation(s)
- Hui Shen
- Department of Periodontology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, Shanghai, China
- National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, China
| | - Yiting Jiang
- Department of Periodontology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, Shanghai, China
- National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, China
| | - Che Qiu
- Department of Periodontology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, Shanghai, China
- National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, China
| | - Xinyi Xie
- Department of Periodontology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, Shanghai, China
- National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, China
| | - Huanyu Zhang
- Department of Periodontology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, Shanghai, China
- National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, China
| | - Zhiyan He
- National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, China
- Laboratory of Oral Microbiota and Systemic Diseases, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, Shanghai, China
| | - Zhongchen Song
- Department of Periodontology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, Shanghai, China
- National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, China
| | - Wei Zhou
- National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, China
- Laboratory of Oral Microbiota and Systemic Diseases, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, Shanghai, China
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10
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Brown GC, Heneka MT. The endotoxin hypothesis of Alzheimer's disease. Mol Neurodegener 2024; 19:30. [PMID: 38561809 PMCID: PMC10983749 DOI: 10.1186/s13024-024-00722-y] [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: 11/17/2023] [Accepted: 03/18/2024] [Indexed: 04/04/2024] Open
Abstract
Lipopolysaccharide (LPS) constitutes much of the surface of Gram-negative bacteria, and if LPS enters the human body or brain can induce inflammation and act as an endotoxin. We outline the hypothesis here that LPS may contribute to the pathophysiology of Alzheimer's disease (AD) via peripheral infections or gut dysfunction elevating LPS levels in blood and brain, which promotes: amyloid pathology, tau pathology and microglial activation, contributing to the neurodegeneration of AD. The evidence supporting this hypothesis includes: i) blood and brain levels of LPS are elevated in AD patients, ii) AD risk factors increase LPS levels or response, iii) LPS induces Aβ expression, aggregation, inflammation and neurotoxicity, iv) LPS induces TAU phosphorylation, aggregation and spreading, v) LPS induces microglial priming, activation and neurotoxicity, and vi) blood LPS induces loss of synapses, neurons and memory in AD mouse models, and cognitive dysfunction in humans. However, to test the hypothesis, it is necessary to test whether reducing blood LPS reduces AD risk or progression. If the LPS endotoxin hypothesis is correct, then treatments might include: reducing infections, changing gut microbiome, reducing leaky gut, decreasing blood LPS, or blocking LPS response.
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Affiliation(s)
- Guy C Brown
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom.
| | - Michael T Heneka
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Belvaux, Luxembourg
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11
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Rubinstein T, Brickman AM, Cheng B, Burkett S, Park H, Annavajhala MK, Uhlemann A, Andrews H, Gutierrez J, Paster BJ, Noble JM, Papapanou PN. Periodontitis and brain magnetic resonance imaging markers of Alzheimer's disease and cognitive aging. Alzheimers Dement 2024; 20:2191-2208. [PMID: 38278517 PMCID: PMC10984451 DOI: 10.1002/alz.13683] [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: 10/13/2023] [Revised: 12/11/2023] [Accepted: 12/12/2023] [Indexed: 01/28/2024]
Abstract
INTRODUCTION We examined the association of clinical, microbiological, and host response features of periodontitis with MRI markers of atrophy/cerebrovascular disease in the Washington Heights Inwood Columbia Aging Project (WHICAP) Ancillary Study of Oral Health. METHODS We analyzed 468 participants with clinical periodontal data, microbial plaque and serum samples, and brain MRIs. We tested the association of periodontitis features with MRI features, after adjusting for multiple risk factors for Alzheimer's disease/Alzheimer's disease-related dementia (AD/ADRD). RESULTS In fully adjusted models, having more teeth was associated with lower odds for infarcts, lower white matter hyperintensity (WMH) volume, higher entorhinal cortex volume, and higher cortical thickness. Higher extent of periodontitis was associated with lower entorhinal cortex volume and lower cortical thickness. Differential associations emerged between colonization by specific bacteria/serum antibacterial IgG responses and MRI outcomes. DISCUSSION In an elderly cohort, clinical, microbiological, and serological features of periodontitis were associated with MRI findings related to ADRD risk. Further investigation of causal associations is warranted.
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Affiliation(s)
- Tom Rubinstein
- Division of PeriodonticsSection of OralDiagnostic and Rehabilitation SciencesCollege of Dental MedicineNew YorkNew YorkUSA
| | - Adam M. Brickman
- Department of NeurologyVagelos College of Physicians and SurgeonsNew YorkNew YorkUSA
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain and Gertrude H. Sergievsky CenterNew YorkNew YorkUSA
| | - Bin Cheng
- Department of BiostatisticsMailman School of Public HealthNew YorkNew YorkUSA
| | - Sandra Burkett
- Division of PeriodonticsSection of OralDiagnostic and Rehabilitation SciencesCollege of Dental MedicineNew YorkNew YorkUSA
| | - Heekuk Park
- Division of Infectious DiseasesDepartment of MedicineVagelos College of Physicians and, Surgeons, Irving Medical CenterColumbia UniversityNew YorkNew YorkUSA
| | - Medini K. Annavajhala
- Division of Infectious DiseasesDepartment of MedicineVagelos College of Physicians and, Surgeons, Irving Medical CenterColumbia UniversityNew YorkNew YorkUSA
| | - Anne‐Catrin Uhlemann
- Division of Infectious DiseasesDepartment of MedicineVagelos College of Physicians and, Surgeons, Irving Medical CenterColumbia UniversityNew YorkNew YorkUSA
| | - Howard Andrews
- Department of BiostatisticsMailman School of Public HealthNew YorkNew YorkUSA
| | - Jose Gutierrez
- Department of NeurologyVagelos College of Physicians and SurgeonsNew YorkNew YorkUSA
| | - Bruce J. Paster
- The Forsyth InstituteCambridgeMassachusettsUSA
- Department of Oral Medicine, Infection and ImmunityHarvard School of Dental MedicineBostonMassachusettsUSA
| | - James M. Noble
- Department of NeurologyVagelos College of Physicians and SurgeonsNew YorkNew YorkUSA
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain and Gertrude H. Sergievsky CenterNew YorkNew YorkUSA
| | - Panos N. Papapanou
- Division of PeriodonticsSection of OralDiagnostic and Rehabilitation SciencesCollege of Dental MedicineNew YorkNew YorkUSA
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12
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Liu S, Butler CA, Ayton S, Reynolds EC, Dashper SG. Porphyromonas gingivalis and the pathogenesis of Alzheimer's disease. Crit Rev Microbiol 2024; 50:127-137. [PMID: 36597758 DOI: 10.1080/1040841x.2022.2163613] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 12/21/2022] [Accepted: 12/23/2022] [Indexed: 01/05/2023]
Abstract
The cause of Alzheimer's disease (AD), and the pathophysiological mechanisms involved, remain major unanswered questions in medical science. Oral bacteria, especially those species associated with chronic periodontitis and particularly Porphyromonas gingivalis, are being linked causally to AD pathophysiology in a subpopulation of susceptible individuals. P. gingivalis produces large amounts of proteolytic enzymes, haem and iron capture proteins, adhesins and internalins that are secreted and attached to the cell surface and concentrated onto outer membrane vesicles (OMVs). These enzymes and adhesive proteins have been shown to cause host tissue damage and stimulate inflammatory responses. The ecological and pathophysiological roles of P. gingivalis OMVs, their ability to disperse widely throughout the host and deliver functional proteins lead to the proposal that they may be the link between a P. gingivalis focal infection in the subgingivae during periodontitis and neurodegeneration in AD. P. gingivalis OMVs can cross the blood brain barrier and may accelerate AD-specific neuropathology by increasing neuroinflammation, plaque/tangle formation and dysregulation of iron homeostasis, thereby inducing ferroptosis leading to neuronal death and neurodegeneration.
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Affiliation(s)
- Sixin Liu
- School of Dentistry, University of Michigan, Ann Arbor, United States of America
| | - Catherine A Butler
- Centre for Oral Health Research, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Parkville, Australia
| | - Scott Ayton
- Melbourne Dementia Research Centre, Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Australia
| | - Eric C Reynolds
- Centre for Oral Health Research, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Parkville, Australia
| | - Stuart G Dashper
- Centre for Oral Health Research, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Parkville, Australia
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13
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Mohammadi-Pilehdarboni H, Shenagari M, Joukar F, Naziri H, Mansour-Ghanaei F. Alzheimer's disease and microorganisms: the non-coding RNAs crosstalk. Front Cell Neurosci 2024; 17:1256100. [PMID: 38249527 PMCID: PMC10796784 DOI: 10.3389/fncel.2023.1256100] [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: 07/10/2023] [Accepted: 10/25/2023] [Indexed: 01/23/2024] Open
Abstract
Alzheimer's disease (AD) is a complex, multifactorial disorder, influenced by a multitude of variables ranging from genetic factors, age, and head injuries to vascular diseases, infections, and various other environmental and demographic determinants. Among the environmental factors, the role of the microbiome in the genesis of neurodegenerative disorders (NDs) is gaining increased recognition. This paradigm shift is substantiated by an extensive body of scientific literature, which underscores the significant contributions of microorganisms, encompassing viruses and gut-derived bacteria, to the pathogenesis of AD. The mechanism by which microbial infection exerts its influence on AD hinges primarily on inflammation. Neuroinflammation, activated in response to microbial infections, acts as a defense mechanism for the brain but can inadvertently lead to unexpected neuropathological perturbations, ultimately contributing to NDs. Given the ongoing uncertainty surrounding the genetic factors underpinning ND, comprehensive investigations into environmental factors, particularly the microbiome and viral agents, are imperative. Recent advances in neuroscientific research have unveiled the pivotal role of non-coding RNAs (ncRNAs) in orchestrating various pathways integral to neurodegenerative pathologies. While the upstream regulators governing the pathological manifestations of microorganisms remain elusive, an in-depth exploration of the nuanced role of ncRNAs holds promise for the development of prospective therapeutic interventions. This review aims to elucidate the pivotal role of ncRNAs as master modulators in the realm of neurodegenerative conditions, with a specific focus on Alzheimer's disease.
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Affiliation(s)
- Hanieh Mohammadi-Pilehdarboni
- Faculty of Medicine and Dentistry and the School of Biological and Behavioural Sciences, Queen Mary University of London, London, United Kingdom
- Gastrointestinal and Liver Diseases Research Center, Guilan University of Medical Sciences, Rasht, Iran
| | - Mohammad Shenagari
- Gastrointestinal and Liver Diseases Research Center, Guilan University of Medical Sciences, Rasht, Iran
- Department of Microbiology, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
| | - Farahnaz Joukar
- Gastrointestinal and Liver Diseases Research Center, Guilan University of Medical Sciences, Rasht, Iran
| | - Hamed Naziri
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, United States
| | - Fariborz Mansour-Ghanaei
- Gastrointestinal and Liver Diseases Research Center, Guilan University of Medical Sciences, Rasht, Iran
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14
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Villar A, Paladini S, Cossatis J. Periodontal Disease and Alzheimer's: Insights from a Systematic Literature Network Analysis. J Prev Alzheimers Dis 2024; 11:1148-1165. [PMID: 39044527 PMCID: PMC11266257 DOI: 10.14283/jpad.2024.79] [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: 01/16/2024] [Accepted: 03/03/2024] [Indexed: 07/25/2024]
Abstract
This study investigated the relationship between periodontal disease (PD) and Alzheimer's Disease (AD) through a Systematic Literature Network Analysis (SLNA), combining bibliometric analysis with a Systematic Literature Review (SLR). Analyzing 328 documents from 2000 to 2023, we utilized the Bibliometrix R-package for multiple bibliometric analysis. The SLR primarily centered on the 47 most globally cited papers, highlighting influential research. Our study reveals a positive correlation between Periodontal Disease (PD) and Alzheimer's Disease (AD), grounded in both biological plausibility and a comprehensive review of the literature, yet the exact causal relationship remains a subject of ongoing scientific investigation. We conducted a detailed analysis of the two main pathways by which PD could contribute to brain inflammation: (a) the Inflammatory Cascade, and (b) Microbial Involvement. The results of our SLNA emphasize the importance of oral health in reducing Alzheimer's risk, suggesting that managing periodontal health could be an integral part of Alzheimer's prevention and treatment strategies. The insights from this SLNA pave the way for future research and clinical practices, underscoring the necessity of interdisciplinary methods in both the investigation and treatment of neurodegenerative diseases like Alzheimer's. Furthermore, our study presents a prospective research roadmap to support ongoing advancement in this field.
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Affiliation(s)
- A Villar
- Alice Villar, Faculty of Medicine, University Castelo Branco (UCB), Brazil,
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15
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Zürcher C, Humpel C. Saliva: a challenging human fluid to diagnose brain disorders with a focus on Alzheimer's disease. Neural Regen Res 2023; 18:2606-2610. [PMID: 37449596 DOI: 10.4103/1673-5374.373675] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2023] Open
Abstract
Biomarkers are molecules of biological processes that help in both the diagnosis of human diseases and in follow-up assessments of therapeutic responses. Biomarkers can be measured in many human fluids, such as blood, cerebrospinal fluid, urine, and saliva. The -omics methods (genomics, RNomics, proteomics, and metabolomics) are useful at measuring thousands of markers in a small volume. Saliva is a human fluid that is easily accessible, without any ethical concerns. Yet, saliva remains unexplored in regard to many human disease biomarkers. In this review, we will give an overview on saliva and how it can be influenced by exogenous factors. As we focus on the potential use of saliva as a diagnostic tool in brain disorders (especially Alzheimer's disease), we will cover how saliva is linked to the brain. We will discuss that saliva is a heterogeneous human fluid, yet useful for the discovery of biomarkers in human disorders. However, a procedure and consensus that is controlled, validated, and standardized for the collection and processing of saliva is required, followed by a highly sensitive diagnostic approach.
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Affiliation(s)
- Christine Zürcher
- University Hospital for Restorative Dentistry and Periodontology, Medical University of Innsbruck, Innsbruck, Austria
| | - Christian Humpel
- Laboratory of Psychiatry & Experimental Alzheimer's Research, Department of Psychiatry I, Medical University of Innsbruck, Innsbruck, Austria
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16
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Yoo JE, Huh Y, Park SH, Han K, Park HS, Cho KH, Ahn JS, Jun SH, Nam GE. Association between Dental Diseases and Oral Hygiene Care and the Risk of Dementia: A Retrospective Cohort Study. J Am Med Dir Assoc 2023; 24:1924-1930.e3. [PMID: 37709259 DOI: 10.1016/j.jamda.2023.08.011] [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: 05/23/2023] [Revised: 08/09/2023] [Accepted: 08/10/2023] [Indexed: 09/16/2023]
Abstract
OBJECTIVES To investigate the associations of dental diseases and oral hygiene care with the risk of dementia. DESIGN Retrospective longitudinal cohort study. SETTING AND PARTICIPANTS We conducted a population-based study of individuals in the Korean National Health Insurance System. A total of 2,555,618 participants who underwent cardiovascular and dental screenings in 2008 were included. METHODS Dental diseases including periodontal diseases, dental caries, and tooth loss were assessed by dentists. Information on oral hygiene care, including professional dental cleaning and the frequency of tooth brushing, was collected using a self-administered questionnaire. Study outcomes were all-cause dementia, Alzheimer's disease (AD), and vascular dementia (VaD). RESULTS Periodontal diseases [adjusted hazard ratio (aHR) 1.07, 95% CI 1.04-1.09], dental caries (aHR 1.03, 95% CI 1.00-1.05), and 8-14 missing teeth (aHR 1.07, 95% CI 1.02-1.12) were associated with an increased risk of all-cause dementia. In contrast, either professional dental cleaning or frequent tooth brushing were associated with decreased risks of all-cause dementia (aHR 0.91, 95% CI 0.89-0.93 each; aHR 0.83, 95% CI 0.80-0.86 for both). The increased risks by dental diseases were reduced by oral hygiene care: periodontal diseases with professional dental cleaning (aHR 0.94, 95% CI 0.91-0.98) or tooth brushing ≥2 times/day (aHR 0.97, 95% CI 0.94-1.00) and 1 to 7 missing teeth with professional dental cleaning (aHR 0.94, 95% CI 0.89-0.98) or tooth brushing ≥2 times/day (aHR 0.92, 95% CI 0.89-0.95). Consistent results were noted for AD and VaD and in various subgroup analyses. CONCLUSION AND IMPLICATIONS Periodontal disease, dental caries, and a high number of missing teeth were independently associated with a higher risk of dementia. Conversely, improved oral hygiene care, such as professional dental cleaning and frequent tooth brushing, may modify the risk of dementia associated with dental diseases.
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Affiliation(s)
- Jung Eun Yoo
- Department of Family Medicine, Healthcare System Gangnam Center Seoul National University Hospital, Seoul, Republic of Korea; Department of Family Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Youn Huh
- Department of Family Medicine, Uijeongbu Eulji Medical Center, Eulji University, Gyeonggi-do, Republic of Korea
| | - Sang-Hyun Park
- Department of Medical Statistics, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Kyungdo Han
- Department of Statistics and Actuarial Science, Soongsil University, Seoul, Republic of Korea
| | - Hye Soon Park
- Department of Family Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Kyung Hwan Cho
- Department of Family Medicine, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Republic of Korea
| | - Jin-Soo Ahn
- Department of Dental Biomaterials Science and Dental Research Institute, School of Dentistry, Seoul National University, Seoul, Republic of Korea
| | - Sang Ho Jun
- Department of Oral & Maxillofacial Surgery, Korea University Anam Hospital, Seoul, Republic of Korea.
| | - Ga Eun Nam
- Department of Family Medicine, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Republic of Korea.
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17
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Tang D, Sun C, Yang J, Fan L, Wang Y. Advances in the Study of the Pathology and Treatment of Alzheimer's Disease and Its Association with Periodontitis. Life (Basel) 2023; 13:2203. [PMID: 38004343 PMCID: PMC10672606 DOI: 10.3390/life13112203] [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: 10/11/2023] [Revised: 11/06/2023] [Accepted: 11/08/2023] [Indexed: 11/26/2023] Open
Abstract
Alzheimer's disease (AD) has become one of the leading causes of health problems in the elderly, and studying its causes and treatments remains a serious challenge for researchers worldwide. The two main pathological features of Alzheimer's disease are the extracellular deposition of β-amyloid (Aβ) to form senile plaques and the intracellular aggregation of hyperphosphorylated Tau protein to form neurofibrillary tangles (NFTs). Researchers have proposed several hypotheses to elucidate the pathogenesis of AD, but due to the complexity of the pathophysiologic factors involved in the development of AD, no effective drugs have been found to stop the progression of the disease. Currently, the mainstay drugs used to treat AD can only alleviate the patient's symptoms and do not have a therapeutic effect. As researchers explore interactions among diseases, much evidence suggests that there is a close link between periodontitis and AD, and that periodontal pathogenic bacteria can exacerbate Aβ deposition and Tau protein hyperphosphorylation through neuroinflammatory mechanisms, thereby advancing the pathogenesis of AD. This article reviews recent advances in the pathogenesis of AD, available therapeutic agents, the relevance of periodontitis to AD, and mechanisms of action.
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Affiliation(s)
- Dan Tang
- School of Life Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, China; (C.S.); (L.F.)
| | - Chang Sun
- School of Life Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, China; (C.S.); (L.F.)
| | - Jumei Yang
- Lanzhou University Second Hospital, Lanzhou 730000, China;
| | - Lili Fan
- School of Life Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, China; (C.S.); (L.F.)
| | - Yonggang Wang
- School of Life Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, China; (C.S.); (L.F.)
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18
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Kulkarni MS, Miller BC, Mahani M, Mhaskar R, Tsalatsanis A, Jain S, Yadav H. Poor Oral Health Linked with Higher Risk of Alzheimer's Disease. Brain Sci 2023; 13:1555. [PMID: 38002515 PMCID: PMC10669972 DOI: 10.3390/brainsci13111555] [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: 10/19/2023] [Revised: 10/26/2023] [Accepted: 11/03/2023] [Indexed: 11/26/2023] Open
Abstract
Alzheimer's disease (AD) is a multifactorial neurodegenerative disease characterized by cognitive and behavioral changes in older adults. Emerging evidence suggests poor oral health is associated with AD, but there is a lack of large-scale clinical studies demonstrating this link. Herein, we used the TriNetX database to generate clinical cohorts and assess the risk of AD and survival among >30 million de-identified subjects with normal oral health (n = 31,418,814) and poor oral health (n = 1,232,751). There was a greater than two-fold increase in AD risk in the poor oral health cohort compared to the normal oral health group (risk ratio (RR): 2.363, (95% confidence interval: 2.326, 2.401)). To reduce potential bias, we performed retrospective propensity score matching for age, gender, and multiple laboratory measures. After matching, the cohorts had no significant differences in survival probability. Furthermore, when comparing multiple oral conditions, diseases related to tooth loss were the most significant risk factor for AD (RR: 3.186, (95% CI: 3.007, 3.376)). Our results suggest that oral health may be important in AD risk, regardless of age, gender, or laboratory measures. However, more large-scale cohort studies are necessary to validate these findings and further evaluate links between oral health and AD.
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Affiliation(s)
- Mihir S. Kulkarni
- USF Center for Microbiome Research, Microbiomes Institute, Department of Neurosurgery and Brain Repair, University of South Florida, Tampa, FL 33612, USA
| | - Brandi C. Miller
- USF Center for Microbiome Research, Microbiomes Institute, Department of Neurosurgery and Brain Repair, University of South Florida, Tampa, FL 33612, USA
- USF Center for Microbiome Research, Microbiomes Institute, Department of Molecular Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Manan Mahani
- USF Center for Microbiome Research, Microbiomes Institute, Department of Neurosurgery and Brain Repair, University of South Florida, Tampa, FL 33612, USA
| | - Rahul Mhaskar
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Athanasios Tsalatsanis
- Research Methodology and Biostatistics Core, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Shalini Jain
- USF Center for Microbiome Research, Microbiomes Institute, Department of Neurosurgery and Brain Repair, University of South Florida, Tampa, FL 33612, USA
| | - Hariom Yadav
- USF Center for Microbiome Research, Microbiomes Institute, Department of Neurosurgery and Brain Repair, University of South Florida, Tampa, FL 33612, USA
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19
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Walker A, Czyz DM. Oh my gut! Is the microbial origin of neurodegenerative diseases real? Infect Immun 2023; 91:e0043722. [PMID: 37750713 PMCID: PMC10580905 DOI: 10.1128/iai.00437-22] [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] [Indexed: 09/27/2023] Open
Abstract
There is no cure or effective treatment for neurodegenerative protein conformational diseases (PCDs), such as Alzheimer's or Parkinson's diseases, mainly because the etiology of these diseases remains elusive. Recent data suggest that unique changes in the gut microbial composition are associated with these ailments; however, our current understanding of the bacterial role in the pathogenesis of PCDs is hindered by the complexity of the microbial communities associated with specific microbiomes, such as the gut, oral, or vaginal microbiota. The composition of these specific microbiomes is regarded as a unique fingerprint affected by factors such as infections, diet, lifestyle, and antibiotics. All of these factors also affect the severity of neurodegenerative diseases. The majority of studies that reveal microbial contribution are correlational, and various models, including worm, fly, and mouse, are being utilized to decipher the role of individual microbes that may affect disease onset and progression. Recent evidence from across model organisms and humans shows a positive correlation between the presence of gram-negative enteropathogenic bacteria and the pathogenesis of PCDs. While these correlational studies do not provide a mechanistic explanation, they do reveal contributing bacterial species and provide an important basis for further investigation. One of the lurking concerns related to the microbial contribution to PCDs is the increasing prevalence of antibiotic resistance and poor antibiotic stewardship, which ultimately select for proteotoxic bacteria, especially the gram-negative species that are known for intrinsic resistance. In this review, we summarize what is known about individual microbial contribution to PCDs and the potential impact of increasing antimicrobial resistance.
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Affiliation(s)
- Alyssa Walker
- Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida, USA
| | - Daniel M. Czyz
- Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida, USA
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20
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Yang M, Xu J, Chen X, Liu L, Kong D, Yang Y, Chen W, Li Z, Zhang X. Sex-based influential factors for dental caries in patients with schizophrenia. BMC Psychiatry 2023; 23:735. [PMID: 37817127 PMCID: PMC10566046 DOI: 10.1186/s12888-023-05256-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 10/04/2023] [Indexed: 10/12/2023] Open
Abstract
BACKGROUND Schizophrenia is a common mental disorder that seriously affects patients' daily lives and brings heavy psychological and economic burdens to their families and society. The oral problems of patients with schizophrenia are gradually gaining attention, among which dental caries are among the most common oral diseases. Sex differences may be related not only to the various clinical symptoms of schizophrenia but also to different oral hygiene statuses; therefore, the main purpose of this paper is to investigate sex differences related to influencing factors for dental caries in patients with schizophrenia. METHOD Inpatients with schizophrenia over 18 years old were included in this study, and multidimensional indicators such as demographics, symptom and cognitive impairment assessments, medications, and the caries index of decayed, missing, and filled teeth (DMFT) were collected. An analysis of sex-based influential factors for dental caries in schizophrenia patients was performed. RESULTS Four-hundred and ninety-six patients with schizophrenia were included, with a mean age of 46.73 ± 12.23 years, of which 142 were females and 354 were males. The mean DMFT was significantly higher in males (8.81 ± 8.50) than in females (5.63 ± 6.61, p < 0.001), and the odd ratio of caries in males to females was significantly higher as well (OR = 2.305, p < 0.001). The influential factors of caries in male patients were independently associated with age and smoking status, in which current smokers were at the highest risk for developing caries, and different smoking statuses had various influencing factors for caries. The influencing factors for caries in female patients were independently associated with age, antipsychotic dose, PANSS-positive symptoms, and MMSE levels. CONCLUSION Our findings suggest sex differences exist among influential factors for caries in patients with schizophrenia. These risk factors may even be associated with and affect the treatment and prognosis of psychiatric symptoms in patients. Therefore, oral hygiene management of patients with schizophrenia should be enhanced. These differential factors provide new visions and ideas for formulating individual interventions, treatments, and care priorities.
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Affiliation(s)
- Mi Yang
- Department of Psychiatry, The Fourth People’s Hospital of Chengdu, No.8 Huli-West 1st-Alley, Jinniu District, Chengdu, 610036 China
- MOE Key Lab for Neuroinformation, The Clinical Hospital of Chengdu Brain Science Institute, University of Electronic Science and Technology of China, Qingshuihe Campus: No.2006, Xiyuan Ave, West Hi-Tech Zone, Chengdu, 611731 China
- School of Life Science and Technology, University of Electronic Science and Technology of China, Qingshuihe Campus: No.2006, Xiyuan Ave, West Hi-Tech Zone, Chengdu, 611731 China
| | - Jingjing Xu
- Department of Psychiatry, Qingdao mental health center, No. 299, Nanjing Road, Qingdao, 266034 China
| | - Xiaoqin Chen
- Department of Psychiatry, Qingdao mental health center, No. 299, Nanjing Road, Qingdao, 266034 China
| | - Liju Liu
- School of Life Science and Technology, University of Electronic Science and Technology of China, Qingshuihe Campus: No.2006, Xiyuan Ave, West Hi-Tech Zone, Chengdu, 611731 China
| | - Di Kong
- Department of Psychiatry, The Fourth People’s Hospital of Chengdu, No.8 Huli-West 1st-Alley, Jinniu District, Chengdu, 610036 China
| | - Yan Yang
- Department of Psychiatry, The Fourth People’s Hospital of Chengdu, No.8 Huli-West 1st-Alley, Jinniu District, Chengdu, 610036 China
| | - Wei Chen
- Department of Psychiatry, The Fourth People’s Hospital of Chengdu, No.8 Huli-West 1st-Alley, Jinniu District, Chengdu, 610036 China
| | - Zezhi Li
- Department of Nutritional and Metabolic Psychiatry, The Affiliated Brain Hospital of Guangzhou Medical University, 36 Mingxin Road, Liwan District, Guangzhou, 510370 China
- Department of Psychiatry, Guangdong Engineering Technology Research Center for Translational Medicine of Mental Disorders, 36 Mingxin Road, Liwan District, Guangzhou, 510370 China
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province, Ministry of Education of China, Guangzhou Medical University, 36 Mingxin Road, Liwan District, Guangzhou, 510370 China
| | - Xiangyang Zhang
- CAS Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, 16 Lincui Road, Chaoyang District, Beijing, 100101 China
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21
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Zhao C, Kuraji R, Ye C, Gao L, Radaic A, Kamarajan P, Taketani Y, Kapila YL. Nisin a probiotic bacteriocin mitigates brain microbiome dysbiosis and Alzheimer's disease-like neuroinflammation triggered by periodontal disease. J Neuroinflammation 2023; 20:228. [PMID: 37803465 PMCID: PMC10557354 DOI: 10.1186/s12974-023-02915-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Accepted: 09/28/2023] [Indexed: 10/08/2023] Open
Abstract
INTRODUCTION Periodontitis-related oral microbial dysbiosis is thought to contribute to Alzheimer's disease (AD) neuroinflammation and brain amyloid production. Since probiotics can modulate periodontitis/oral dysbiosis, this study examined the effects of a probiotic/lantibiotic, nisin, in modulating brain pathology triggered by periodontitis. METHODS A polymicrobial mouse model of periodontal disease was used to evaluate the effects of this disease on brain microbiome dysbiosis, neuroinflammation, Alzheimer's-related changes, and nisin's therapeutic potential in this context. RESULTS 16S sequencing and real-time PCR data revealed that Nisin treatment mitigated the changes in the brain microbiome composition, diversity, and community structure, and reduced the levels of periodontal pathogen DNA in the brain induced by periodontal disease. Nisin treatment significantly decreased the mRNA expression of pro-inflammatory cytokines (Interleukin-1β/IL-1 β, Interleukin 6/IL-6, and Tumor Necrosis Factor α/TNF-α) in the brain that were elevated by periodontal infection. In addition, the concentrations of amyloid-β 42 (Aβ42), total Tau, and Tau (pS199) (445.69 ± 120.03, 1420.85 ± 331.40, 137.20 ± 36.01) were significantly higher in the infection group compared to the control group (193.01 ± 31.82, 384.27 ± 363.93, 6.09 ± 10.85), respectively. Nisin treatment markedly reduced the Aβ42 (261.80 ± 52.50), total Tau (865.37 ± 304.93), and phosphorylated Tau (82.53 ± 15.77) deposition in the brain of the infection group. DISCUSSION Nisin abrogation of brain microbiome dysbiosis induces beneficial effects on AD-like pathogenic changes and neuroinflammation, and thereby may serve as a potential therapeutic for periodontal-dysbiosis-related AD.
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Affiliation(s)
- Chuanjiang Zhao
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, CA, 94143, USA
- Department of Periodontology, Hospital of Stomatology, Sun Yat-Sen University, Guangzhou, 510050, China
- Guangdong Provincial Key Laboratory of Stomatology, Guanghua School of Stomatology, Sun Yat-Sen University, Guangzhou, 510050, China
| | - Ryutaro Kuraji
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, CA, 94143, USA
- Department of Periodontology, The Nippon Dental University School of Life Dentistry at Tokyo, Tokyo, 102-8159, Japan
| | - Changchang Ye
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, CA, 94143, USA
- Department of Periodontology, West China School of Stomatology, National Clinical Research Center for Oral Diseases, State Key Laboratory of Oral Diseases, Sichuan University, Chengdu, 610093, China
| | - Li Gao
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, CA, 94143, USA
- Department of Periodontology, Hospital of Stomatology, Sun Yat-Sen University, Guangzhou, 510050, China
- Guangdong Provincial Key Laboratory of Stomatology, Guanghua School of Stomatology, Sun Yat-Sen University, Guangzhou, 510050, China
| | - Allan Radaic
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, CA, 94143, USA
- Department of Biosystems and Function and Periodontics, School of Dentistry, University of California Los Angeles, Los Angeles, CA, 90024, USA
| | - Pachiyappan Kamarajan
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, CA, 94143, USA
- Department of Biosystems and Function and Periodontics, School of Dentistry, University of California Los Angeles, Los Angeles, CA, 90024, USA
| | - Yoshimasa Taketani
- Department of Biosystems and Function and Periodontics, School of Dentistry, University of California Los Angeles, Los Angeles, CA, 90024, USA
- Division of Periodontology, Department of Oral Biology and Tissue Engineering, Meikai University School of Dentistry, Sakado, 350-0283, Japan
| | - Yvonne L Kapila
- Department of Orofacial Sciences, School of Dentistry, University of California San Francisco, San Francisco, CA, 94143, USA.
- Department of Biosystems and Function and Periodontics, School of Dentistry, University of California Los Angeles, Los Angeles, CA, 90024, USA.
- Section of Biosystems and Function, Section of Periodontology, UCLA School of Dentistry, 10833 Le Conte Ave, Box 951668, Los Angeles, CA, 90095-1668, USA.
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22
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Eslami S, Hosseinzadeh Shakib N, Fooladfar Z, Nasrollahian S, Baghaei S, Mosaddad SA, Motamedifar M. The role of periodontitis-associated bacteria in Alzheimer's disease: A narrative review. J Basic Microbiol 2023; 63:1059-1072. [PMID: 37311215 DOI: 10.1002/jobm.202300250] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 06/01/2023] [Accepted: 06/03/2023] [Indexed: 06/15/2023]
Abstract
Alzheimer's disease causes memory loss and dementia in older adults through a neurodegenerative mechanism. Despite the pathophysiological clarification of this cognitive disorder, novel molecular and cellular pathways should be identified to determine its exact mechanism. Alzheimer's disease (AD) is pathologically characterized by senile plaques comprising beta-amyloid and neurofibrillary tangles (NFTs) formed by hyperphosphorylated tau as a microtubule-associated protein with a key role in the pathogenesis of AD. Periodontitis through inflammatory pathways is a risk factor for deteriorating cognitive impairment in AD patients. Poor oral hygiene coupled with immunocompromised status in older adults causes periodontal diseases and chronic inflammations through an oral bacterial imbalance. Toxic bacterial products, including bacteria themselves, can reach the central nervous system through the bloodstream and evoke inflammatory responses. The present review was conducted to investigate relationships between AD and periodontitis-involved bacteria as a risk factor.
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Affiliation(s)
- Saba Eslami
- Research Central Laboratory, Shiraz University of Medical Sciences, Shiraz, Iran
| | | | - Zahra Fooladfar
- Student Research Committee, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Sina Nasrollahian
- Student Research Committee, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Saman Baghaei
- Student Research Committee, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Seyed Ali Mosaddad
- Student Research Committee, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mohammad Motamedifar
- HIV/AIDS Research Center, Institute of Health, Shiraz University of Medical Sciences, Shiraz, Iran
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23
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Bouziane A, Lattaf S, Abdallaoui Maan L. Effect of Periodontal Disease on Alzheimer's Disease: A Systematic Review. Cureus 2023; 15:e46311. [PMID: 37916259 PMCID: PMC10616904 DOI: 10.7759/cureus.46311] [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] [Accepted: 09/28/2023] [Indexed: 11/03/2023] Open
Abstract
The aim of this review was to evaluate the relationship between periodontal disease (PD) and the onset and progression of Alzheimer's disease (AD) and to determine whether patients with PD would be at greater risk of developing AD compared to periodontally healthy subjects. This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. An electronic search for cross-sectional, cohort, or case-control studies was conducted on five databases (PubMed, ScienceDirect, EBSCO, Web of Science, and Scopus). No restrictions were applied to the language and year of publication. Exposure was PD, and the outcome of interest was the onset and/or progression of AD. The risk of bias of the included studies was assessed using the Newcastle-Ottawa Scale (NOS) designed for non-randomized studies. Six studies fulfilling the selection criteria were included in this systematic review. Four of the studies were of cohort design and two were of case-control design. All except one showed a significant association between PD and the risk of AD onset and progression. According to the NOS bias risk assessment, three studies were found to be of good quality, and three other cohort studies were of low quality. Data from this systematic review indicate that patients with PD present a significantly higher risk of AD compared to individuals with healthy periodontium. However, results should be interpreted with caution given the methodological limitations found. For future research, powerful and comparable epidemiological studies are needed to evaluate the relationship between PD and AD.
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Affiliation(s)
- Amal Bouziane
- Department of Periodontology, Faculty of Dental Medicine, Mohammed V University in Rabat, Rabat, MAR
- Laboratory of Biostatistics, Epidemiology, and Clinical Research, Mohammed V University in Rabat, Rabat, MAR
| | - Sara Lattaf
- Department of Periodontology, Faculty of Dental Medicine, Mohammed V University in Rabat, Rabat, MAR
| | - Lamiaa Abdallaoui Maan
- Department of Periodontology, Faculty of Dental Medicine, Mohammed V University in Rabat, Rabat, MAR
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24
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Roldan L, Montoya C, Solanki V, Cai KQ, Yang M, Correa S, Orrego S. A Novel Injectable Piezoelectric Hydrogel for Periodontal Disease Treatment. ACS APPLIED MATERIALS & INTERFACES 2023; 15:43441-43454. [PMID: 37672788 DOI: 10.1021/acsami.3c08336] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/08/2023]
Abstract
Periodontal disease is a multifactorial, bacterially induced inflammatory condition characterized by the progressive destruction of periodontal tissues. The successful nonsurgical treatment of periodontitis requires multifunctional technologies offering antibacterial therapies and promotion of bone regeneration simultaneously. For the first time, in this study, an injectable piezoelectric hydrogel (PiezoGEL) was developed after combining gelatin methacryloyl (GelMA) with biocompatible piezoelectric fillers of barium titanate (BTO) that produce electrical charges when stimulated by biomechanical vibrations (e.g., mastication, movements). We harnessed the benefits of hydrogels (injectable, light curable, conforms to pocket spaces, biocompatible) with the bioactive effects of piezoelectric charges. A thorough biomaterial characterization confirmed piezoelectric fillers' successful integration with the hydrogel, photopolymerizability, injectability for clinical use, and electrical charge generation to enable bioactive effects (antibacterial and bone tissue regeneration). PiezoGEL showed significant reductions in pathogenic biofilm biomass (∼41%), metabolic activity (∼75%), and the number of viable cells (∼2-3 log) compared to hydrogels without BTO fillers in vitro. Molecular analysis related the antibacterial effects to be associated with reduced cell adhesion (downregulation of porP and fimA) and increased oxidative stress (upregulation of oxyR) genes. Moreover, PiezoGEL significantly enhanced bone marrow stem cell (BMSC) viability and osteogenic differentiation by upregulating RUNX2, COL1A1, and ALP. In vivo, PiezoGEL effectively reduced periodontal inflammation and increased bone tissue regeneration compared to control groups in a mice model. Findings from this study suggest PiezoGEL to be a promising and novel therapeutic candidate for the treatment of periodontal disease nonsurgically.
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Affiliation(s)
- Lina Roldan
- Department of Oral Health Sciences, Kornberg School of Dentistry, Temple University, Philadelphia, Pennsylvania 19140, United States
- Bioengineering Research Group (GIB), Universidad EAFIT, Medellín 050037, Colombia
| | - Carolina Montoya
- Department of Oral Health Sciences, Kornberg School of Dentistry, Temple University, Philadelphia, Pennsylvania 19140, United States
| | - Varun Solanki
- Department of Oral Health Sciences, Kornberg School of Dentistry, Temple University, Philadelphia, Pennsylvania 19140, United States
| | - Kathy Q Cai
- Histopathology Facility, Fox Chase Cancer, Temple University, Philadelphia, Pennsylvania 19140, United States
| | - Maobin Yang
- Department of Oral Health Sciences, Kornberg School of Dentistry, Temple University, Philadelphia, Pennsylvania 19140, United States
- Department of Endodontology, Kornberg School of Dentistry, Temple University, Philadelphia, Pennsylvania 19140, United States
| | - Santiago Correa
- Bioengineering Research Group (GIB), Universidad EAFIT, Medellín 050037, Colombia
| | - Santiago Orrego
- Department of Oral Health Sciences, Kornberg School of Dentistry, Temple University, Philadelphia, Pennsylvania 19140, United States
- Bioengineering Department, College of Engineering, Temple University. Philadelphia, Pennsylvania 19122, United States
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25
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Park KM, Lee N, Kim J, Kim HS, Park W. Preventive effect of teriparatide on medication-related osteonecrosis of the jaw in rats. Sci Rep 2023; 13:15518. [PMID: 37726385 PMCID: PMC10509150 DOI: 10.1038/s41598-023-42607-y] [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: 04/20/2023] [Accepted: 09/12/2023] [Indexed: 09/21/2023] Open
Abstract
This study aimed to investigate the preventive effect of teriparatide (TPD) administration on medication-related osteonecrosis of the jaw (MRONJ) before tooth extraction due to periodontal lesions in bilaterally ovariectomized female rats treated with zoledronic acid. Thirty skeletally mature Sprague-Dawley rats were randomly divided into three groups: control (CONT, n = 10), zoledronic acid (ZA, n = 10), and zoledronic acid and teriparatide (ZA-TPD, n = 10). The rats were sacrificed 8 weeks after tooth extraction. Micro-computed tomography analysis of the tibia showed that bone mineral density was highest in the CONT, followed by that in the ZA and ZA-TPD groups (CONT/ZA, p = 0.009; CONT/ZA-TPD, p < 0.001; ZA/ZA-TPD, p < 0.001). In the trabecular bone analysis of the extraction site, significant differences in specific bone surface (CONT/ZA, p = 0.010; CONT/ZA-TPD, p = 0.007; ZA/ZA-TPD, p = 0.002) and trabecular thickness (CONT/ZA-TPD, p = 0.002; ZA/ZA-TPD, p = 0.002) were observed. Histological analyses of the extraction sites revealed characteristic MRONJ lesions in the ZA group. Osteonecrosis, inflammatory cells, and sequestrum were less frequently observed in the ZA-TPD group than in the ZA group. In conclusion, TPD administration before tooth extraction helped reduce the occurrence of MRONJ in rats treated with zoledronic acid, confirming its preventative effects.
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Affiliation(s)
- Kyeong-Mee Park
- Department of Advanced General Dentistry, Human Identification Research Institute, Yonsei University College of Dentistry, Seoul, Republic of Korea
| | - Namkwon Lee
- Department of Advanced General Dentistry, Yonsei University College of Dentistry, Seoul, Republic of Korea
| | - Jaeyeon Kim
- Department of Advanced General Dentistry, Yonsei University College of Dentistry, Seoul, Republic of Korea
| | - Hyun Sil Kim
- Department of Oral Pathology, Oral Cancer Research Institute, Yonsei University College of Dentistry, Seoul, Republic of Korea
| | - Wonse Park
- Department of Advanced General Dentistry, Human Identification Research Institute, Yonsei University College of Dentistry, Seoul, Republic of Korea.
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26
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Shiheido-Watanabe Y, Maejima Y, Nakagama S, Fan Q, Tamura N, Sasano T. Porphyromonas gingivalis, a periodontal pathogen, impairs post-infarcted myocardium by inhibiting autophagosome-lysosome fusion. Int J Oral Sci 2023; 15:42. [PMID: 37723152 PMCID: PMC10507114 DOI: 10.1038/s41368-023-00251-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 09/04/2023] [Accepted: 09/04/2023] [Indexed: 09/20/2023] Open
Abstract
While several previous studies have indicated the link between periodontal disease (PD) and myocardial infarction (MI), the underlying mechanisms remain unclear. Autophagy, a cellular quality control process that is activated in several diseases, including heart failure, can be suppressed by Porphyromonas gingivalis (P.g.). However, it is uncertain whether autophagy impairment by periodontal pathogens stimulates the development of cardiac dysfunction after MI. Thus, this study aimed to investigate the relationship between PD and the development of MI while focusing on the role of autophagy. Neonatal rat cardiomyocytes (NRCMs) and MI model mice were inoculated with wild-type P.g. or gingipain-deficient P.g. to assess the effect of autophagy inhibition by P.g. Wild-type P.g.-inoculated NRCMs had lower cell viability than those inoculated with gingipain-deficient P.g. This study also revealed that gingipains can cleave vesicle-associated membrane protein 8 (VAMP8), a protein involved in lysosomal sensitive factor attachment protein receptors (SNAREs), at the 47th lysine residue, thereby inhibiting autophagy. Wild-type P.g.-inoculated MI model mice were more susceptible to cardiac rupture, with lower survival rates and autophagy activity than gingipain-deficient P.g.-inoculated MI model mice. After inoculating genetically modified MI model mice (VAMP8-K47A) with wild-type P.g., they exhibited significantly increased autophagy activation compared with the MI model mice inoculated with wild-type P.g., which suppressed cardiac rupture and enhanced overall survival rates. These findings suggest that gingipains, which are virulence factors of P.g., impair the infarcted myocardium by cleaving VAMP8 and disrupting autophagy. This study confirms the strong association between PD and MI and provides new insights into the potential role of autophagy in this relationship.
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Affiliation(s)
- Yuka Shiheido-Watanabe
- Department of Cardiovascular Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yasuhiro Maejima
- Department of Cardiovascular Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan.
| | - Shun Nakagama
- Department of Cardiovascular Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Qintao Fan
- Department of Cardiovascular Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Natsuko Tamura
- Department of Cardiovascular Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Tetsuo Sasano
- Department of Cardiovascular Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
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27
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Rego S, Sanchez G, Da Mesquita S. Current views on meningeal lymphatics and immunity in aging and Alzheimer's disease. Mol Neurodegener 2023; 18:55. [PMID: 37580702 PMCID: PMC10424377 DOI: 10.1186/s13024-023-00645-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 08/02/2023] [Indexed: 08/16/2023] Open
Abstract
Alzheimer's disease (AD) is an aging-related form of dementia associated with the accumulation of pathological aggregates of amyloid beta and neurofibrillary tangles in the brain. These phenomena are accompanied by exacerbated inflammation and marked neuronal loss, which altogether contribute to accelerated cognitive decline. The multifactorial nature of AD, allied to our still limited knowledge of its etiology and pathophysiology, have lessened our capacity to develop effective treatments for AD patients. Over the last few decades, genome wide association studies and biomarker development, alongside mechanistic experiments involving animal models, have identified different immune components that play key roles in the modulation of brain pathology in AD, affecting its progression and severity. As we will relay in this review, much of the recent efforts have been directed to better understanding the role of brain innate immunity, and particularly of microglia. However, and despite the lack of diversity within brain resident immune cells, the brain border tissues, especially the meninges, harbour a considerable number of different types and subtypes of adaptive and innate immune cells. Alongside microglia, which have taken the centre stage as important players in AD research, there is new and exciting evidence pointing to adaptive immune cells, namely T and B cells found in the brain and its meninges, as important modulators of neuroinflammation and neuronal (dys)function in AD. Importantly, a genuine and functional lymphatic vascular network is present around the brain in the outermost meningeal layer, the dura. The meningeal lymphatics are directly connected to the peripheral lymphatic system in different mammalian species, including humans, and play a crucial role in preserving a "healthy" immune surveillance of the CNS, by shaping immune responses, not only locally at the meninges, but also at the level of the brain tissue. In this review, we will provide a comprehensive view on our current knowledge about the meningeal lymphatic vasculature, emphasizing its described roles in modulating CNS fluid and macromolecule drainage, meningeal and brain immunity, as well as glial and neuronal function in aging and in AD.
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Affiliation(s)
- Shanon Rego
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
- Post-baccalaureate Research Education Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Guadalupe Sanchez
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
- Neuroscience Ph.D. Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Sandro Da Mesquita
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA.
- Post-baccalaureate Research Education Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Jacksonville, FL, 32224, USA.
- Neuroscience Ph.D. Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Jacksonville, FL, 32224, USA.
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28
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López-Villodres JA, Escamilla A, Mercado-Sáenz S, Alba-Tercedor C, Rodriguez-Perez LM, Arranz-Salas I, Sanchez-Varo R, Bermúdez D. Microbiome Alterations and Alzheimer's Disease: Modeling Strategies with Transgenic Mice. Biomedicines 2023; 11:1846. [PMID: 37509487 PMCID: PMC10377071 DOI: 10.3390/biomedicines11071846] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 06/21/2023] [Accepted: 06/23/2023] [Indexed: 07/30/2023] Open
Abstract
In the last decade, the role of the microbiota-gut-brain axis has been gaining momentum in the context of many neurodegenerative and metabolic disorders, including Alzheimer's disease (AD) and diabetes, respectively. Notably, a balanced gut microbiota contributes to the epithelial intestinal barrier maintenance, modulates the host immune system, and releases neurotransmitters and/or neuroprotective short-chain fatty acids. However, dysbiosis may provoke immune dysregulation, impacting neuroinflammation through peripheral-central immune communication. Moreover, lipopolysaccharide or detrimental microbial end-products can cross the blood-brain barrier and induce or at least potentiate the neuropathological progression of AD. Thus, after repeated failure to find a cure for this dementia, a necessary paradigmatic shift towards considering AD as a systemic disorder has occurred. Here, we present an overview of the use of germ-free and/or transgenic animal models as valid tools to unravel the connection between dysbiosis, metabolic diseases, and AD, and to investigate novel therapeutical targets. Given the high impact of dietary habits, not only on the microbiota but also on other well-established AD risk factors such as diabetes or obesity, consistent changes of lifestyle along with microbiome-based therapies should be considered as complementary approaches.
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Affiliation(s)
- Juan Antonio López-Villodres
- Departamento Fisiologia Humana, Histologia Humana, Anatomia Patologica y Educacion Fisica y Deportiva, Facultad de Medicina, Universidad de Malaga, 29071 Malaga, Spain
| | - Alejandro Escamilla
- Departamento Fisiologia Humana, Histologia Humana, Anatomia Patologica y Educacion Fisica y Deportiva, Facultad de Medicina, Universidad de Malaga, 29071 Malaga, Spain
- Instituto de Investigacion Biomedica de Malaga-IBIMA-Plataforma Bionand, 29071 Malaga, Spain
| | - Silvia Mercado-Sáenz
- Departamento Fisiologia Humana, Histologia Humana, Anatomia Patologica y Educacion Fisica y Deportiva, Facultad de Medicina, Universidad de Malaga, 29071 Malaga, Spain
| | - Carmen Alba-Tercedor
- Departamento Fisiologia Humana, Histologia Humana, Anatomia Patologica y Educacion Fisica y Deportiva, Facultad de Medicina, Universidad de Malaga, 29071 Malaga, Spain
| | - Luis Manuel Rodriguez-Perez
- Departamento Fisiologia Humana, Histologia Humana, Anatomia Patologica y Educacion Fisica y Deportiva, Facultad de Medicina, Universidad de Malaga, 29071 Malaga, Spain
- Instituto de Investigacion Biomedica de Malaga-IBIMA-Plataforma Bionand, 29071 Malaga, Spain
| | - Isabel Arranz-Salas
- Departamento Fisiologia Humana, Histologia Humana, Anatomia Patologica y Educacion Fisica y Deportiva, Facultad de Medicina, Universidad de Malaga, 29071 Malaga, Spain
- Instituto de Investigacion Biomedica de Malaga-IBIMA-Plataforma Bionand, 29071 Malaga, Spain
- Unidad de Anatomia Patologica, Hospital Universitario Virgen de la Victoria, 29010 Malaga, Spain
| | - Raquel Sanchez-Varo
- Departamento Fisiologia Humana, Histologia Humana, Anatomia Patologica y Educacion Fisica y Deportiva, Facultad de Medicina, Universidad de Malaga, 29071 Malaga, Spain
- Instituto de Investigacion Biomedica de Malaga-IBIMA-Plataforma Bionand, 29071 Malaga, Spain
- Centro de Investigacion Biomedica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
| | - Diego Bermúdez
- Departamento Fisiologia Humana, Histologia Humana, Anatomia Patologica y Educacion Fisica y Deportiva, Facultad de Medicina, Universidad de Malaga, 29071 Malaga, Spain
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29
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Lyra P, Machado V, Rota S, Chaudhuri KR, Botelho J, Mendes JJ. Revisiting Alpha-Synuclein Pathways to Inflammation. Int J Mol Sci 2023; 24:ijms24087137. [PMID: 37108299 PMCID: PMC10138587 DOI: 10.3390/ijms24087137] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 04/10/2023] [Accepted: 04/11/2023] [Indexed: 04/29/2023] Open
Abstract
Alpha-synuclein (α-Syn) is a short presynaptic protein with an active role on synaptic vesicle traffic and the neurotransmitter release and reuptake cycle. The α-Syn pathology intertwines with the formation of Lewy Bodies (multiprotein intraneuronal aggregations), which, combined with inflammatory events, define various α-synucleinopathies, such as Parkinson's Disease (PD). In this review, we summarize the current knowledge on α-Syn mechanistic pathways to inflammation, as well as the eventual role of microbial dysbiosis on α-Syn. Furthermore, we explore the possible influence of inflammatory mitigation on α-Syn. In conclusion, and given the rising burden of neurodegenerative disorders, it is pressing to clarify the pathophysiological processes underlying α-synucleinopathies, in order to consider the mitigation of existing low-grade chronic inflammatory states as a potential pathway toward the management and prevention of such conditions, with the aim of starting to search for concrete clinical recommendations in this particular population.
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Affiliation(s)
- Patrícia Lyra
- Egas Moniz Center for Interdisciplinary Research (CiiEM), Egas Moniz School of Health and Science, Caparica, 2829-511 Almada, Portugal
- Evidence-Based Hub, CiiEM, Egas Moniz-Cooperativa de Ensino Superior, Caparica, 2829-511 Almada, Portugal
| | - Vanessa Machado
- Egas Moniz Center for Interdisciplinary Research (CiiEM), Egas Moniz School of Health and Science, Caparica, 2829-511 Almada, Portugal
- Evidence-Based Hub, CiiEM, Egas Moniz-Cooperativa de Ensino Superior, Caparica, 2829-511 Almada, Portugal
| | - Silvia Rota
- Department of Basic & Clinical Neuroscience, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London WC2R 2LS, UK
- Parkinson's Foundation Center of Excellence, King's College Hospital, London SE5 9RS, UK
| | - Kallol Ray Chaudhuri
- Department of Basic & Clinical Neuroscience, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London WC2R 2LS, UK
- Parkinson's Foundation Center of Excellence, King's College Hospital, London SE5 9RS, UK
| | - João Botelho
- Egas Moniz Center for Interdisciplinary Research (CiiEM), Egas Moniz School of Health and Science, Caparica, 2829-511 Almada, Portugal
- Evidence-Based Hub, CiiEM, Egas Moniz-Cooperativa de Ensino Superior, Caparica, 2829-511 Almada, Portugal
| | - José João Mendes
- Egas Moniz Center for Interdisciplinary Research (CiiEM), Egas Moniz School of Health and Science, Caparica, 2829-511 Almada, Portugal
- Evidence-Based Hub, CiiEM, Egas Moniz-Cooperativa de Ensino Superior, Caparica, 2829-511 Almada, Portugal
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Wang RPH, Huang J, Chan KWY, Leung WK, Goto T, Ho YS, Chang RCC. IL-1β and TNF-α play an important role in modulating the risk of periodontitis and Alzheimer's disease. J Neuroinflammation 2023; 20:71. [PMID: 36915108 PMCID: PMC10012546 DOI: 10.1186/s12974-023-02747-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 02/21/2023] [Indexed: 03/16/2023] Open
Abstract
BACKGROUND Systemic activation of the immune system can exert detrimental effects on the central nervous system. Periodontitis, a chronic disease of the oral cavity, is a common source of systemic inflammation. Neuroinflammation might be a result of this to accelerate progressive deterioration of neuronal functions during aging or exacerbate pre-existing neurodegenerative diseases, such as Alzheimer's disease. With advancing age, the progressive increase in the body's pro-inflammatory status favors the state of vulnerability to both periodontitis and Alzheimer's disease. In the present study, we sought to delineate the roles of cytokines in the pathogenesis of both diseases. METHODS To examine the impacts of periodontitis on the onset and progression of Alzheimer's disease, 6-month-old female 3 × Tg-AD mice and their age-matched non-transgenic mice were employed. Periodontitis was induced using two different experimental models: heat-killed bacterial-induced periodontitis and ligature-induced periodontitis. To delineate the roles of pro-inflammatory cytokines in the pathogenesis of periodontitis and Alzheimer's disease, interleukin 1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) were also injected into the buccal mandibular vestibule of mice. RESULTS Here, we show that IL-1β and TNF-α were two of the most important and earliest cytokines upregulated upon periodontal infection. The systemic upregulation of these two cytokines promoted a pro-inflammatory environment in the brain contributing to the development of Alzheimer's disease-like pathology and cognitive dysfunctions. Periodontitis-induced systemic inflammation also enhanced brain inflammatory responses and subsequently exacerbated Alzheimer's disease pathology and cognitive impairment in 3 × Tg-AD mice. The role of inflammation in connecting periodontitis to Alzheimer's disease was further affirmed in the conventional magnetization transfer experiment in which increased glial responses resulting from periodontitis led to decreased magnetization transfer ratios in the brain of 3 × Tg-AD mice. CONCLUSIONS Systemic inflammation resulting from periodontitis contributed to the development of Alzheimer's disease tau pathology and subsequently led to cognitive decline in non-transgenic mice. It also potentiated Alzheimer's disease pathological features and exacerbated impairment of cognitive function in 3 × Tg-AD mice. Taken together, this study provides convincing evidence that systemic inflammation serves as a connecting link between periodontitis and Alzheimer's disease.
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Affiliation(s)
- Rachel Pei-Hsuan Wang
- Laboratory of Neurodegenerative Diseases, School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Laboratory Block, Rm. L4-49, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - Jianpan Huang
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong SAR, China
| | - Kannie Wai Yan Chan
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong SAR, China
| | - Wai Keung Leung
- Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
| | - Tetsuya Goto
- Division of Oral Anatomy and Histology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Yuen-Shan Ho
- School of Nursing, Faculty of Health and Social Sciences, Hong Kong Polytechnic University, Hunghom, Kowloon, Hong Kong SAR, China
| | - Raymond Chuen-Chung Chang
- Laboratory of Neurodegenerative Diseases, School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Laboratory Block, Rm. L4-49, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China. .,State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
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Mizobuchi H. Oral route lipopolysaccharide as a potential dementia preventive agent inducing neuroprotective microglia. Front Immunol 2023; 14:1110583. [PMID: 36969154 PMCID: PMC10033586 DOI: 10.3389/fimmu.2023.1110583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 02/27/2023] [Indexed: 03/11/2023] Open
Abstract
In today’s aging society, dementia is an urgent problem to be solved because no treatment or preventive methods have been established. This review focuses on oral administration of lipopolysaccharide (LPS), an outer membrane component of Gram-negative bacteria, as a novel preventive drug for dementia. LPS is also called endotoxin and is well known to induce inflammation when administered systemically. On the other hand, although we humans routinely ingest LPS derived from symbiotic bacteria of edible plants, the effect of oral administration of LPS has hardly been studied. Recently, oral administration of LPS was reported to prevent dementia by inducing neuroprotective microglia. Furthermore, it has been suggested that colony stimulating factor 1 (CSF1) is involved in the dementia prevention mechanism by oral administration of LPS. Thus, in this review, we summarized the previous studies of oral administration of LPS and discussed the predicted dementia prevention mechanism. In addition, we showed the potential of oral LPS administration as a preventive drug for dementia by highlighting research gaps and future issues for clinical application development.
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Yusuf K, Sampath V, Umar S. Bacterial Infections and Cancer: Exploring This Association And Its Implications for Cancer Patients. Int J Mol Sci 2023; 24:3110. [PMID: 36834525 PMCID: PMC9958598 DOI: 10.3390/ijms24043110] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 01/31/2023] [Accepted: 02/01/2023] [Indexed: 02/08/2023] Open
Abstract
Bacterial infections are common in the etiology of human diseases owing to the ubiquity of bacteria. Such infections promote the development of periodontal disease, bacterial pneumonia, typhoid, acute gastroenteritis, and diarrhea in susceptible hosts. These diseases may be resolved using antibiotics/antimicrobial therapy in some hosts. However, other hosts may be unable to eliminate the bacteria, allowing them to persist for long durations and significantly increasing the carrier's risk of developing cancer over time. Indeed, infectious pathogens are modifiable cancer risk factors, and through this comprehensive review, we highlight the complex relationship between bacterial infections and the development of several cancer types. For this review, searches were performed on the PubMed, Embase, and Web of Science databases encompassing the entirety of 2022. Based on our investigation, we found several critical associations, of which some are causative: Porphyromonas gingivalis and Fusobacterium nucleatum are associated with periodontal disease, Salmonella spp., Clostridium perfringens, Escherichia coli, Campylobacter spp., and Shigella are associated with gastroenteritis. Helicobacter pylori infection is implicated in the etiology of gastric cancer, and persistent Chlamydia infections present a risk factor for the development of cervical carcinoma, especially in patients with the human papillomavirus (HPV) coinfection. Salmonella typhi infections are linked with gallbladder cancer, and Chlamydia pneumoniae infection is implicated in lung cancer, etc. This knowledge helps identify the adaptation strategies used by bacteria to evade antibiotic/antimicrobial therapy. The article also sheds light on the role of antibiotics in cancer treatment, the consequences of their use, and strategies for limiting antibiotic resistance. Finally, the dual role of bacteria in cancer development as well as in cancer therapy is briefly discussed, as this is an area that may help to facilitate the development of novel microbe-based therapeutics as a means of securing improved outcomes.
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Affiliation(s)
- Kafayat Yusuf
- Department of Surgery, University of Kansas Medical Center, Kansas City, KS 66160, USA
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Venkatesh Sampath
- Department of Pediatrics and Gastroenterology, Children’s Mercy Hospital, Kansas City, KS 66160, USA
| | - Shahid Umar
- Department of Surgery, University of Kansas Medical Center, Kansas City, KS 66160, USA
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA
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Chandra S, Sisodia SS, Vassar RJ. The gut microbiome in Alzheimer's disease: what we know and what remains to be explored. Mol Neurodegener 2023; 18:9. [PMID: 36721148 PMCID: PMC9889249 DOI: 10.1186/s13024-023-00595-7] [Citation(s) in RCA: 60] [Impact Index Per Article: 60.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 01/06/2023] [Indexed: 02/02/2023] Open
Abstract
Alzheimer's disease (AD), the most common cause of dementia, results in a sustained decline in cognition. There are currently few effective disease modifying therapies for AD, but insights into the mechanisms that mediate the onset and progression of disease may lead to new, effective therapeutic strategies. Amyloid beta oligomers and plaques, tau aggregates, and neuroinflammation play a critical role in neurodegeneration and impact clinical AD progression. The upstream modulators of these pathological features have not been fully clarified, but recent evidence indicates that the gut microbiome (GMB) may have an influence on these features and therefore may influence AD progression in human patients. In this review, we summarize studies that have identified alterations in the GMB that correlate with pathophysiology in AD patients and AD mouse models. Additionally, we discuss findings with GMB manipulations in AD models and potential GMB-targeted therapeutics for AD. Lastly, we discuss diet, sleep, and exercise as potential modifiers of the relationship between the GMB and AD and conclude with future directions and recommendations for further studies of this topic.
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Affiliation(s)
- Sidhanth Chandra
- Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
- Medical Scientist Training Program, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | - Sangram S. Sisodia
- Department of Neurobiology, University of Chicago, Chicago, IL 60637 USA
| | - Robert J. Vassar
- Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
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Lamphere AK, Nieto VK, Kiser JR, Haddlesey CB. Potential mechanisms between periodontitis and Alzheimer's disease: a scoping review. CANADIAN JOURNAL OF DENTAL HYGIENE : CJDH = JOURNAL CANADIEN DE L'HYGIENE DENTAIRE : JCHD 2023; 57:52-60. [PMID: 36968797 PMCID: PMC10032644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 08/03/2022] [Accepted: 10/25/2022] [Indexed: 03/29/2023]
Abstract
Background Research has suggested 2 potential mechanisms by which the periodontal inflammatory response may communicate to distant organs: 1) direct translocation of periodontal bacteria from the oral cavity to another organ system; and 2) inflammation as a result of metastatic periodontal inflammation. The purpose of this scoping review is to explore these mechanisms as potential mediators between periodontitis and Alzheimer's disease. Methods A reiterative literature search of peer-reviewed articles was performed in the PubMed and Scopus databases using keywords or combinations such as Alzheimer's disease AND periodontitis OR periodontal disease AND inflammation. Results A total of 777 articles were identified. After eliminating duplicates and reviewing titles and abstracts, 84 articles were selected for full-text review. Following full-text review, 19 articles met the eligibility criteria for the study. Discussion The review of the literature highlights how periodontitis may contribute to neuroinflammation by the introduction of periodontal bacteria and/or proinflammatory cytokines locally produced at the periodontium. Conclusion Inflammation is an important mechanism in the onset and progression of both periodontitis and Alzheimer's disease. Nevertheless, further studies are necessary to better understand the multifactorial pathogenesis of Alzheimer's disease.
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Affiliation(s)
- Abrielle K Lamphere
- Assistant clinical professor in dentistry, University of Indiana School of Dentistry, Indianapolis, IN, USA
| | - Valerie K Nieto
- Clinical lecturer in dentistry, University of Michigan School of Dentistry, Ann Arbor, MI, USA
| | - Jessica R Kiser
- Adjunct clinical lecturer in dentistry, University of Michigan School of Dentistry, Ann Arbor, MI, USA
| | - Chris B Haddlesey
- Adjunct clinical lecturer in dentistry, University of Michigan School of Dentistry, Ann Arbor, MI, USA
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35
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Grobler C, van Tongeren M, Gettemans J, Kell DB, Pretorius E. Alzheimer's Disease: A Systems View Provides a Unifying Explanation of Its Development. J Alzheimers Dis 2023; 91:43-70. [PMID: 36442193 DOI: 10.3233/jad-220720] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Alzheimer's disease (AD) is a debilitating neurodegenerative disorder affecting 50 million people globally. It is characterized by the presence of extracellular senile plaques and intracellular neurofibrillary tangles, consisting of amyloid-β and hyperphosphorylated tau proteins, respectively. Despite global research efforts, there is currently no cure available, due in part to an incomplete understanding of the disease pathogenesis. Numerous possible mechanisms, or hypotheses, explaining the origins of sporadic or late-onset AD have been proposed, including the amyloid-β, inflammatory, vascular, and infectious hypotheses. However, despite ample evidence, the failure of multiple trial drugs at the clinical stage illuminates the possible pitfalls of these hypotheses. Systems biology is a strategy which aims to elucidate the interactions between parts of a whole. Using this approach, the current paper shows how the four previously mentioned hypotheses of AD pathogenesis can be intricately connected. This approach allows for seemingly contradictory evidence to be unified in a system-focused explanation of sporadic AD development. Within this view, it is seen that infectious agents, such as P. gingivalis, may play a central role. The data presented here shows that when present, P. gingivalis or its virulence factors, such as gingipains, may induce or exacerbate pathologies underlying sporadic AD. This evidence supports the view that infectious agents, and specifically P. gingivalis, may be suitable treatment targets in AD.
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Affiliation(s)
- Corlia Grobler
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa
| | - Marvi van Tongeren
- Department of Biomolecular Medicine, Faculty of Medicine & Health Sciences, Ghent University, Ghent, Belgium
| | - Jan Gettemans
- Department of Biomolecular Medicine, Faculty of Medicine & Health Sciences, Ghent University, Ghent, Belgium
| | - Douglas B Kell
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa.,Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, UK.,The Novo Nordisk Foundation Centre for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Etheresia Pretorius
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa.,Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, UK
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36
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Liu S, Dashper SG, Zhao R. Association Between Oral Bacteria and Alzheimer's Disease: A Systematic Review and Meta-Analysis. J Alzheimers Dis 2023; 91:129-150. [PMID: 36404545 DOI: 10.3233/jad-220627] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Pre-clinical evidence implicates oral bacteria in the pathogenesis of Alzheimer's disease (AD), while clinical studies show diverse results. OBJECTIVE To comprehensively assess the association between oral bacteria and AD with clinical evidence. METHODS Studies investigating the association between oral bacteria and AD were identified through a systematic search of six databases PubMed, Embase, Cochrane Central Library, Scopus, ScienceDirect, and Web of Science. Methodological quality ratings of the included studies were performed. A best evidence synthesis was employed to integrate the results. When applicable, a meta-analysis was conducted using a random-effect model. RESULTS Of the 16 studies included, ten investigated periodontal pathobionts and six were microbiome-wide association studies. Samples from the brain, serum, and oral cavity were tested. We found over a ten-fold and six-fold increased risk of AD when there were oral bacteria (OR = 10.68 95% CI: 4.48-25.43; p < 0.00001, I2 = 0%) and Porphyromonas gingivalis (OR = 6.84 95% CI: 2.70-17.31; p < 0.0001, I2 = 0%) respectively in the brain. While AD patients exhibited lower alpha diversity of oral microbiota than healthy controls, the findings of bacterial communities were inconsistent among studies. The best evidence synthesis suggested a moderate level of evidence for an overall association between oral bacteria and AD and for oral bacteria being a risk factor for AD. CONCLUSION Current evidence moderately supports the association between oral bacteria and AD, while the association was strong when oral bacteria were detectable in the brain. Further evidence is needed to clarify the interrelationship between both individual species and bacterial communities and the development of AD.
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Affiliation(s)
- Sixin Liu
- School of Dentistry, University of Michigan, Ann Arbor, MI, USA
| | - Stuart G Dashper
- Centre for Oral Health Research, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Parkville, Australia
| | - Rui Zhao
- Department of Stomatology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
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MORIKAWA TETSURO, UEHARA OSAMU, PAUDEL DURGA, YOSHIDA KOKI, HARADA FUMIYA, HIRAKI DAICHI, SATO JUN, MATSUOKA HIROFUMI, KURAMITSU YASUHIRO, MICHIKAWA MAKOTO, ABIKO YOSHIHIRO. Systemic Administration of Lipopolysaccharide from Porphyromonas gingivalis Decreases Neprilysin Expression in the Mouse Hippocampus. In Vivo 2023; 37:163-172. [PMID: 36593043 PMCID: PMC9843806 DOI: 10.21873/invivo.13065] [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: 11/16/2022] [Revised: 11/29/2022] [Accepted: 11/30/2022] [Indexed: 01/03/2023]
Abstract
BACKGROUND/AIM Alzheimer's disease is the most common type of neurodegenerative disorder in elderly individuals worldwide. Increasing evidence suggests that periodontal diseases are involved in the pathogenesis of Alzheimer's disease, and an association between periodontitis and amyloid-β deposition in elderly individuals has been demonstrated. The aim of the present study was to examine the effects of systemic administration of Porphyromonas gingivalis-derived lipopolysaccharide (PG-LPS) on neprilysin expression in the hippocampus of adult and senescence-accelerated mice. MATERIALS AND METHODS PG-LPS diluted in saline was intraperitoneally administered to male C57BL/6J and senescence-accelerated mouse prone 8 (SAMP8) mice at a dose of 5 mg/kg every 3 days for 3 months. Both C57BL/6J and SAMP8 mice administered saline without PG-LPS comprised the control group. The mRNA expression levels of neprilysin and interleukin (IL)-10 were evaluated using the quantitative reverse transcriptase-polymerase chain reaction. The protein levels of neprilysin were assessed using western blotting. Sections of the brain tissues were immunohistochemically stained. RESULTS The serum IL-10 concentration significantly increased in both mouse strains after stimulation with PG-LPS. Neprilysin expression at both mRNA and protein levels was significantly lower in the SAMP8 PG-LPS group than those in the SAMP8 control group; however, they did not differ in PG-LPS-treated or non-treated C57BL/6J mice. Additionally, the immunofluorescence intensity of neprilysin in the CA3 region of the hippocampus in PG-LPS-treated SAMP8 mice was significantly lower than that in control SAMP8 mice. CONCLUSION Porphyromonas gingivalis may reduce the expression of neprilysin in elderly individuals and thus increase amyloid-β deposition.
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Affiliation(s)
- TETSURO MORIKAWA
- Division of Oral Medicine and Pathology, Department of Human Biology and Pathophysiology, School of Dentistry, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Japan
| | - OSAMU UEHARA
- Division of Disease Control and Molecular Epidemiology, Department of Oral Growth and Development, School of Dentistry, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Japan
| | - DURGA PAUDEL
- Advanced Research Promotion Center, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Japan
| | - KOKI YOSHIDA
- Division of Oral Medicine and Pathology, Department of Human Biology and Pathophysiology, School of Dentistry, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Japan
| | - FUMIYA HARADA
- Division of Oral and Maxillofacial Surgery, Department of Human Biology and Pathophysiology, School of Dentistry, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Japan
| | - DAICHI HIRAKI
- Division of Reconstructive Surgery for Oral and Maxillofacial Region, Department of Human Biology and Pathophysiology, School of Dentistry, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Japan
| | - JUN SATO
- Division of Oral Medicine and Pathology, Department of Human Biology and Pathophysiology, School of Dentistry, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Japan
| | - HIROFUMI MATSUOKA
- Division of Disease Control and Molecular Epidemiology, Department of Oral Growth and Development, School of Dentistry, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Japan
| | - YASUHIRO KURAMITSU
- Advanced Research Promotion Center, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Japan
| | - MAKOTO MICHIKAWA
- Department of Biochemistry, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - YOSHIHIRO ABIKO
- Division of Oral Medicine and Pathology, Department of Human Biology and Pathophysiology, School of Dentistry, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Japan
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Inoue M, Kimoto K, Honma Y, Tomita R, Manabe Y. Oral environment and cerebral blood flow in patients with neurodegenerative dementia: comparison of Alzheimer type dementia and dementia with Lewy bodies. Psychogeriatrics 2023; 23:23-31. [PMID: 36273804 DOI: 10.1111/psyg.12899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 09/22/2022] [Accepted: 10/10/2022] [Indexed: 01/05/2023]
Abstract
BACKGROUND The number of patients with dementia is increasing worldwide. Modifying risk factors may significantly reduce the prevalence and cost of dementia. The number of remaining teeth, occlusal force, denture use, and periodontal disease status are associated with the risk of developing dementia. The oral environment may be a risk factor for dementia. This study aimed to investigate the association between the oral environment and cerebral blood flow in patients with mild cognitive impairment and dementia (either Alzheimer type dementia (ATD) or dementia with Lewy bodies (DLB)). We aimed to identify differences in the oral environment according to the underlying neurodegenerative disease. METHODS The participants were 25 patients with ATD and 25 patients with DLB who visited the Department of Dementia and Geriatric Medicine, Kanagawa Dental University Hospital. Patients were diagnosed with ATD and DLB by well-trained specialists certified by the Japanese Dementia Society and categorised as Level 3 or 4 by the Functional Assessment Staging of Alzheimer Disease scale. The correlation between oral environment (number of teeth, periodontal tissue, and oral function) and cerebral blood flow in each brain area calculated by single photon emission computed tomography was examined. RESULTS The DLB group showed a significant correlation between masticatory performance and cerebral blood flow in some areas, while no such correlation was observed in the ATD group. Significant correlations were found between periodontal pocket depth and bleeding on probing and cerebral blood flow in some areas in both groups, although the correlation was considerable in the ATD group. CONCLUSIONS The results of this study suggest that the association between changes in the oral environment and cerebral blood flow may differ among patients with ATD and DLB, depending on the underlying causative disease.
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Affiliation(s)
- Makoto Inoue
- Department of Fixed Prosthodontics, Kanagawa Dental University, Yokosuka, Japan
| | - Katsuhiko Kimoto
- Department of Fixed Prosthodontics, Kanagawa Dental University, Yokosuka, Japan
| | - Yuta Honma
- Department of Fixed Prosthodontics, Kanagawa Dental University, Yokosuka, Japan
| | - Rintaro Tomita
- Department of Fixed Prosthodontics, Kanagawa Dental University, Yokosuka, Japan
| | - Yuta Manabe
- Department of Dementia and Geriatric Medicine, Kanagawa Dental University, Yokosuka, Japan
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Matsumoto H, Tagai K, Endo H, Matsuoka K, Takado Y, Kokubo N, Shimada H, Goto T, Goto TK, Higuchi M. Association of Tooth Loss with Alzheimer's Disease Tau Pathologies Assessed by Positron Emission Tomography. J Alzheimers Dis 2023; 96:1253-1265. [PMID: 37980663 PMCID: PMC10741329 DOI: 10.3233/jad-230581] [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] [Accepted: 09/24/2023] [Indexed: 11/21/2023]
Abstract
BACKGROUND Deterioration of the oral environment is one of the risk factors for dementia. A previous study of an Alzheimer's disease (AD) model mouse suggests that tooth loss induces denervation of the mesencephalic trigeminal nucleus and neuroinflammation, possibly leading to accelerated tau dissemination from the nearby locus coeruleus (LC). OBJECTIVE To elucidate the relevance of oral conditions and amyloid-β (Aβ) and tau pathologies in human participants. METHODS We examined the number of remaining teeth and the biofilm-gingival interface index in 24 AD-spectrum patients and 19 age-matched healthy controls (HCs). They also underwent positron emission tomography (PET) imaging of Aβ and tau with specific radiotracers, 11C-PiB and 18F-PM-PBB3, respectively. All AD-spectrum patients were Aβ-positive, and all HCs were Aβ-negative. We analyzed the correlation between the oral parameters and radiotracer retention. RESULTS No differences were found in oral conditions between the AD and HC groups. 11C-PiB retentions did not correlate with the oral indices in either group. In AD-spectrum patients, brain-wide, voxel-based image analysis highlighted several regions, including the LC and associated brainstem substructures, as areas where 18F-PM-PBB3 retentions negatively correlated with the remaining teeth and revealed the correlation of tau deposits in the LC (r = -0.479, p = 0.018) primarily with the hippocampal and neighboring areas. The tau deposition in none of the brain regions was associated with the periodontal status. CONCLUSIONS Our findings with previous preclinical evidence imply that tooth loss may enhance AD tau pathogenesis, promoting tau spreading from LC to the hippocampal formation.
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Affiliation(s)
- Hideki Matsumoto
- Department of Oral and Maxillofacial Radiology, Tokyo Dental College, Tokyo, Japan
- Department of Functional Brain Imaging Research, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Kenji Tagai
- Department of Functional Brain Imaging Research, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan
- Department of Psychiatry, The Jikei University of Medicine, Tokyo, Japan
| | - Hironobu Endo
- Department of Functional Brain Imaging Research, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Kiwamu Matsuoka
- Department of Functional Brain Imaging Research, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Yuhei Takado
- Department of Functional Brain Imaging Research, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Naomi Kokubo
- Department of Functional Brain Imaging Research, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Hitoshi Shimada
- Department of Functional Brain Imaging Research, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan
- Department of Functional Neurology & Neurosurgery, Center for Integrated Human Brain Science, Brain Research Institute, Niigata University, Niigata, Japan
| | - Tetsuya Goto
- Department of Oral Anatomy and Cell Biology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Tazuko K. Goto
- Department of Oral and Maxillofacial Radiology, Tokyo Dental College, Tokyo, Japan
- Department of Functional Brain Imaging Research, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan
- Tokyo Dental College Research Branding Project, Tokyo Dental College, Tokyo, Japan
- Faculty of Dentistry, The University of Hong Kong, Hong Kong, China
| | - Makoto Higuchi
- Department of Functional Brain Imaging Research, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan
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40
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Dziedzic A. Is Periodontitis Associated with Age-Related Cognitive Impairment? The Systematic Review, Confounders Assessment and Meta-Analysis of Clinical Studies. Int J Mol Sci 2022; 23:15320. [PMID: 36499656 PMCID: PMC9739281 DOI: 10.3390/ijms232315320] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/27/2022] [Accepted: 11/29/2022] [Indexed: 12/12/2022] Open
Abstract
It has been suggested that molecular pathological mechanisms responsible for periodontitis can be linked with biochemical alterations in neurodegenerative disorders. Hypothetically, chronic systemic inflammation as a response to periodontitis plays a role in the etiology of cognitive impairment. This study aimed to determine whether periodontitis (PDS) is a risk factor for age-related cognitive impairment (ACI) based on evidence of clinical studies. A comprehensive, structured systematic review of existing data adhering to the Preferred Reporting Items for Systematic Review and Meta Analyses (PRISMA) guidelines was carried out. Five electronic databases, PubMed, Embase, Scopus, Web of Science, and Cochrane, were searched for key terms published in peer-reviewed journals until January 2021. The Newcastle-Ottawa scale was used to assess the quality of studies and risk of bias. The primary and residual confounders were explored and evaluated. A meta-analysis synthesizing quantitative data was carried out using a random-effects model. Seventeen clinical studies were identified, including 14 cohort, one cross-sectional, and two case-control studies. Study samples ranged from 85 to 262,349 subjects, with follow-up between 2 and 32 years, and age above 45 years, except for two studies. The findings of studies suggesting the PDS-ACI relationship revealed substantial differences in design and methods. A noticeable variation related to the treatment of confounders was observed. Quality assessment unveiled a moderate quality of evidence and risk of bias. The subgroups meta-analysis and pooled sensitivity analysis of results from seven eligible studies demonstrated overall that the presence of PDS is associated with an increased risk of incidence of cognitive impairment (OR = 1.36, 95% CI 1.03-1.79), particularly dementia (OR = 1.39, 95% CI 1.02-1.88) and Alzheimer's disease (OR = 1.03 95% CI 0.98-1.07)). However, a considerable heterogeneity of synthesized data (I2 = 96%) and potential publication bias might affect obtained results. While there is a moderate statistical association between periodontitis and dementia, as well as Alzheimer's disease, the risk of bias in the evidence prevents conclusions being drawn about the role of periodontitis as a risk factor for age-related cognitive impairment.
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Affiliation(s)
- Arkadiusz Dziedzic
- Department of Conservative Dentistry with Endodontics, Medical University of Silesia, 40-055 Katowice, Poland
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Li X, Kiprowska M, Kansara T, Kansara P, Li P. Neuroinflammation: A Distal Consequence of Periodontitis. J Dent Res 2022; 101:1441-1449. [PMID: 35708472 PMCID: PMC9608094 DOI: 10.1177/00220345221102084] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Periodontitis, a chronic, inflammatory disease, induces systemic inflammation and contributes to the development of neurodegenerative diseases. The precise etiology of the most common neurodegenerative disorders, such as sporadic Alzheimer's, Parkinson's diseases and multiple sclerosis (AD, PD, and MS, respectively), remains to be revealed. Chronic neuroinflammation is a well-recognized component of these disorders, and evidence suggests that systemic inflammation is a possible stimulus for neuroinflammation development. Systemic inflammation can lead to deleterious consequences on the brain if the inflammation is sufficiently severe or if the brain shows vulnerabilities due to genetic predisposition, aging, or neurodegenerative diseases. It has been proposed that periodontal disease can initiate or contribute to the AD pathogenesis through multiple pathways, including key periodontal pathogens. Dysbiotic oral bacteria can release bacterial products into the bloodstream and eventually cross the brain-blood barrier; these bacteria can also cause alterations to gut microbiota that enhance inflammation and potentially affect brain function via the gut-brain axis. The trigeminal nerve has been suggested as another route for connecting oral bacterial products to the brain. PD and MS are often preceded by gastrointestinal symptoms or aberrant gut microbiome composition, and alterations in the enteric nervous system accompany the disease. Clinical evidence has suggested that patients with periodontitis are at a higher risk of developing PD and MS. This nexus among the brain, periodontal disease, and systemic inflammation heralds new ways in which microglial cells, the main innate immune cells, and astrocytes, the crucial regulators of innate and adaptive immune responses in the brain, contribute to brain pathology. Currently, the lack of understanding of the pathogenesis of neurodegeneration is hindering treatment development. However, we may prevent this pathogenesis by tackling one of its possible contributors (periodontitis) for systemic inflammation through simple preventive oral hygiene measures.
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Affiliation(s)
- X. Li
- Department of Molecular Pathobiology, New York University College of Dentistry, New York, NY, USA
- Department of Urology, New York University Grossman School of Medicine, New York, NY, USA
- Perlmutter Cancer Institute, New York University Langone Medical Center, New York, NY, USA
| | - M. Kiprowska
- Department of Molecular Pathobiology, New York University College of Dentistry, New York, NY, USA
| | - T. Kansara
- Cleveland Clinic- Union hospital, Dover, OH, USA
| | - P. Kansara
- Department of Molecular Pathobiology, New York University College of Dentistry, New York, NY, USA
| | - P. Li
- Department of Molecular Pathobiology, New York University College of Dentistry, New York, NY, USA
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Sabbagh MN, Decourt B. COR388 (atuzaginstat): an investigational gingipain inhibitor for the treatment of Alzheimer disease. Expert Opin Investig Drugs 2022; 31:987-993. [PMID: 36003033 PMCID: PMC10275298 DOI: 10.1080/13543784.2022.2117605] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 08/23/2022] [Indexed: 01/07/2023]
Abstract
INTRODUCTION Evidence from in vitro and in vivo studies demonstrates that amyloid beta (Aβ) oligomers have potent, broad-spectrum antimicrobial properties created by fibrils that entrap pathogens and disrupt their membranes. Data suggest that Aβ may play a protective role in the innate immune response to microbial infections and that Aβ in the brain plays a damaging role when the inflammatory response is not well controlled. AREAS COVERED This paper describes the relationship between periodontal disease and Alzheimer disease (AD), the role of Porphyromonas gingivalis and its secreted gingipains in AD, and the potential of the gingipain inhibitor atuzaginstat (COR388) to modulate AD neuropathologies. EXPERT OPINION P. gingivalis is opsonized by Aβ42, is capable of entering the brain, and is an accelerant of neuropathologies in rodent models of AD. Thus, in our opinion, this bacteria is highly likely to be a pathogen capable of initiating or precipitating the progression of AD, which agrees with the pathogen hypothesis of clinical AD development.
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Affiliation(s)
- Marwan N. Sabbagh
- Department of Neurology, Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center, Phoenix Arizona, USA
| | - Boris Decourt
- Translational Neuroscience Lab, Cleveland Clinic Lou Ruvo Center for Brain Health, Las Vegas, Nevada, USA
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Kanagasingam S, von Ruhland C, Welbury R, Chukkapalli SS, Singhrao SK. Porphyromonas gingivalis Conditioned Medium Induces Amyloidogenic Processing of the Amyloid-β Protein Precursor upon in vitro Infection of SH-SY5Y Cells. J Alzheimers Dis Rep 2022; 6:577-587. [PMID: 36275415 PMCID: PMC9535609 DOI: 10.3233/adr-220029] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 08/23/2022] [Indexed: 12/27/2022] Open
Abstract
Background: Cleavage of the amyloid-β protein precursor (AβPP) mediated by host secretase enzymes, releases several fragments including amyloid-β (Aβ40 and Aβ42). Objective: To determine if Porphyromonas gingivalis conditioned medium cleaved AβPP to release Aβ40 and Aβ42. Methods: The SH-SY5Y cell line was challenged, in vitro, with P. gingivalis (Pg381) conditioned medium in the presence/absence of cytokines. The cells and their supernatants were assessed for AβPP cleavage fragments by immunoblotting and transmission electron microscopy. Results: Western blotting of the cell lysates with the anti-AβPP C-terminal antibody demonstrated variable molecular weight bands corresponding to full length and fragmented AβPP in lanes treated with the following factors: Tryptic soy broth (TSB), Pg381, IL-6, Pg381 + IL-1β, and Pg381 + TNF-α. The low molecular weight bands corresponding to the C99 dimerized fragment were observed in the Pg381 and interlukin-6 (IL-6) treated groups and were significantly more intense in the presence of Pg381 with either IL-6 or TNF-α. Bands corresponding to the dimerized C83 fragment were observed with cells treated with TNF-α alone and with Pg381 combined with IL-1β or IL-6 or TNF-α. The anti-Aβ antibody detected statistically significant Aβ40 and Aβ42, levels when these two Aβ species were pooled across test samples and compared to the untreated group. Electron microscopic examination of the supernatants demonstrated insoluble Aβ40 and Aβ42. Conclusion: These observations strongly imply that AβPP is an infection responsive protein cleaved via the amyloidogenic pathway on exposure to conditioned medium and in the presence of pro-inflammatory mediators.
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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
| | - Christopher von Ruhland
- Electron and Light Microscopy Facility, College of Biomedical and Life Sciences, Cardiff University, Wales, 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
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Satur MJ, Urbanowicz PA, Spencer DIR, Rafferty J, Stafford GP. Structural and functional characterisation of a stable, broad-specificity multimeric sialidase from the oral pathogen Tannerella forsythia. Biochem J 2022; 479:1785-1806. [PMID: 35916484 PMCID: PMC9472817 DOI: 10.1042/bcj20220244] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 08/01/2022] [Accepted: 08/02/2022] [Indexed: 11/17/2022]
Abstract
Sialidases are glycosyl hydrolase enzymes targeting the glycosidic bond between terminal sialic acids and underlying sugars. The NanH sialidase of Tannerella forsythia, one of the bacteria associated with severe periodontal disease plays a role in virulence. Here, we show that this broad-specificity enzyme (but higher affinity for α2,3 over α2,6 linked sialic acids) digests complex glycans but not those containing Neu5,9Ac. Furthermore, we show it to be a highly stable dimeric enzyme and present a thorough structural analysis of the native enzyme in its apo-form and in complex with a sialic acid analogue/ inhibitor (Oseltamivir). We also use non-catalytic (D237A) variant to characterise molecular interactions while in complex with the natural substrates 3- and 6-siallylactose. This dataset also reveals the NanH carbohydrate-binding module (CBM, CAZy CBM 93) has a novel fold made of antiparallel beta-strands. The catalytic domain structure contains novel features that include a non-prolyl cis-peptide and an uncommon arginine sidechain rotamer (R306) proximal to the active site. Via a mutagenesis programme, we identified key active site residues (D237, R212 and Y518) and probed the effects of mutation of residues in proximity to the glycosidic linkage within 2,3 and 2,6-linked substrates. These data revealed that mutagenesis of R306 and residues S235 and V236 adjacent to the acid-base catalyst D237 influence the linkage specificity preference of this bacterial sialidase, opening up possibilities for enzyme engineering for glycotechology applications and providing key structural information that for in silico design of specific inhibitors of this enzyme for the treatment of periodontitis.
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Affiliation(s)
- Marianne J. Satur
- School of Clinical Dentistry, The University of Sheffield, 19 Claremont Crescent, Sheffield S10 2TA, U.K
| | | | | | - John Rafferty
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, U.K
| | - Graham P. Stafford
- School of Clinical Dentistry, The University of Sheffield, 19 Claremont Crescent, Sheffield S10 2TA, U.K
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Elwakil BH, Bakr BA, Aljeldah MM, Shehata NS, Shahin YH, Olama ZA, Augustyniak M, Aboul-Soud MAM, El Wakil A. Memory Impairment, Pro-Inflammatory Host Response and Brain Histopathologic Severity in Rats Infected with K. pneumoniae or P. aeruginosa Meningitis. Pathogens 2022; 11:933. [PMID: 36015052 PMCID: PMC9416464 DOI: 10.3390/pathogens11080933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 07/29/2022] [Accepted: 08/02/2022] [Indexed: 11/25/2022] Open
Abstract
Meningitis caused by Klebsiella pneumoniae and Pseudomonas aeruginosa has lately become a prevalent cause of the central nervous system (CNS) infection. Bacterial invasion into the subarachnoid space prompts the releasing mechanism of chemokines and pro-inflammatory cytokines. The present study aimed to compare K. pneumoniae and P. aeruginosa meningitis concerning the memory, pro-inflammatory mediators and brain histopathological changes at different time intervals in adult Albino rats. The animals were sacrificed at three time intervals comprising 5, 10 and 15 days after meningitis induction. Cerebrospinal fluid (CSF) culture, relative brain weights, complete blood analysis, biochemical markers, levels of cytokine, chemokine and brain-derived neurotrophic factor (BDNF), neurotransmitter acetylcholine esterase (AChE) activity, and the brain histopathology of the infected rats in comparison to those in the control group were assessed. There was a significant increase in the levels of pro-inflammatory cytokines and chemokines including TNF-α, IL-1β, IL-6 and AChE after 5 days of bacterial meningitis infection with both K. pneumoniae and P. aeruginosa. The histopathological analysis of the cerebral cortex in the P. aeruginosa meningitis model at different time intervals revealed abundant numbers of dilated and congested blood vessels with severe hemorrhage, cerebral infarct, intracellular and extracellular vacuoles, and gliosis. Fifteen days post infection, a significant reduction in the brain tissue weight was observed. The meningitis model employing P. aeruginosa exhibited more evident time-dependent severity compared to K. pneumoniae, which may advocate its validity as a simple and effective research model to study meningitis of the CNS. This model may be utilized for further investigation to ascertain the molecular and biological association between bacterial meningitis and the development of the pathophysiological hallmarks underlying Alzheimer's disease in preclinical and clinical setups. Clinical extrapolation based on studies employing animal disease models should be carefully interpreted.
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Affiliation(s)
- Bassma H. Elwakil
- Department of Medical Laboratory Technology, Faculty of Applied Health Sciences Technology, Pharos University in Alexandria, Alexandria P.O. Box 21311, Egypt
| | - Basant A. Bakr
- Department of Zoology, Faculty of Science, Alexandria University, Alexandria P.O. Box 21568, Egypt
| | - Mohammed M. Aljeldah
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, University of Hafr Al Batin, Hafr Al Batin 39524, Saudi Arabia
| | - Nourhan S. Shehata
- Department of Medical Laboratory Technology, Faculty of Applied Health Sciences Technology, Pharos University in Alexandria, Alexandria P.O. Box 21311, Egypt
| | - Yahya H. Shahin
- Department of Medical Laboratory Technology, Faculty of Applied Health Sciences Technology, Pharos University in Alexandria, Alexandria P.O. Box 21311, Egypt
| | - Zakia A. Olama
- Department of Botany and Microbiology, Faculty of Science, Alexandria University, Alexandria P.O. Box 21568, Egypt
| | - Maria Augustyniak
- Faculty of Natural Sciences, Institute of Biology, Biotechnology and Environmental Protection, University of Silesia in Katowice, Bankowa 9, 40-007 Katowice, Poland
| | - Mourad A. M. Aboul-Soud
- Chair of Medical and Molecular Genetics Research, Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Saud University, P.O. Box 10219, Riyadh 11433, Saudi Arabia
| | - Abeer El Wakil
- Department of Biological and Geological Sciences, Faculty of Education, Alexandria University, Alexandria P.O. Box 21526, Egypt
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Mao S, Huang CP, Lan H, Lau HG, Chiang CP, Chen YW. Association of periodontitis and oral microbiomes with Alzheimer’s disease: A narrative systematic review. J Dent Sci 2022; 17:1762-1779. [PMID: 36299333 PMCID: PMC9588805 DOI: 10.1016/j.jds.2022.07.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 07/02/2022] [Indexed: 11/26/2022] Open
Abstract
Background/purpose Alzheimer’s disease (AD) is a neurodegenerative disorder and the most common form of dementia. The etiology for AD includes age, genetic susceptibility, neuropathology, and infection. Periodontitis is an infectious and inflammatory disease which mainly causes alveolar bone destruction and tooth loss. The evidence of a link between AD and periodontitis remains controversial. Thus far, studies reviewing the association between AD and periodontal disease have been insufficient from the viewpoint of the oral microbiome. The aim of this review was to focus on studies that have explored the relationship between the oral microbiome and AD development by using the next-generation sequencing technique. Materials and methods A comprehensive electronic search of MEDLINE via PubMed, EMBASE, Scopus, and Google Scholar was conducted. The keywords included dementia, Alzheimer’s disease, cognitive impairment, periodontitis, periodontal disease, and oral microbiome. Results This review included 26 articles based on the eligibility criteria. Epidemiologic researches and post-mortem studies showed that the presence of periodontitis is associated with cognitive decline, suggesting a possible role of periodontal pathogens in the pathogenesis of AD. The reported microbiome was inconsistent with those in gene sequencing studies. Nevertheless, Gram-negative species may be possible candidates. Conclusion This review suggests that periodontal infection is associated with AD. The contributing microbiome remains unconfirmed, possibly because of different microbiome sampling sites or methods. Additional large-scale studies with periodontal intervention and longitudinal follow-up are warranted to clarify the relationship between periodontal disease and AD.
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Wu H, Qiu W, Zhu X, Li X, Xie Z, Carreras I, Dedeoglu A, Van Dyke T, Han YW, Karimbux N, Tu Q, Cheng L, Chen J. The Periodontal Pathogen Fusobacterium nucleatum Exacerbates Alzheimer's Pathogenesis via Specific Pathways. Front Aging Neurosci 2022; 14:912709. [PMID: 35813949 PMCID: PMC9260256 DOI: 10.3389/fnagi.2022.912709] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 06/07/2022] [Indexed: 01/21/2023] Open
Abstract
Alzheimer's Disease (AD) is the most common form of dementia in older adults and has a devastating impact on the patient's quality of life, which creates a significant socio-economic burden for the affected individuals and their families. In recent years, studies have identified a relationship between periodontitis and AD. Periodontitis is an infectious/inflammatory disease that destroys the supporting periodontal structure leading to tooth loss. Dysbiosis of the oral microbiome plays a significant role in the onset and development of periodontitis exhibiting a shift to overgrowth of pathobionts in the normal microflora with increasing local inflammation. Fusobacterium nucleatum is a common pathogen that significantly overgrows in periodontitis and has also been linked to various systemic diseases. Earlier studies have reported that antibodies to F. nucleatum can be detected in the serum of patients with AD or cognitive impairment, but a causal relationship and a plausible mechanism linking the two diseases have not been identified. In this study, we conducted both in vivo and in vitro experiments and found that F. nucleatum activates microglial cells causing morphological changes, accelerated proliferation and enhanced expression of TNF-α and IL-1β in microglial cells. In our in vivo experiments, we found that F. nucleatum-induced periodontitis resulted in the exacerbation of Alzheimer's symptoms in 5XFAD mice including increased cognitive impairment, beta-amyloid accumulation and Tau protein phosphorylation in the mouse cerebrum. This study may suggest a possible link between a periodontal pathogen and AD and F. nucleatum could be a risk factor in the pathogenesis of AD. We are currently further identifying the pathways through which F. nucleatum modulates molecular elements in enhancing AD symptoms and signs. Data are available via ProteomeXchange with identifier PXD033147.
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Affiliation(s)
- Hongle Wu
- Department of Endodontics, Stomatological Hospital, Southern Medical University, Guangzhou, China
- State Key Laboratory of Oral Disease, West China Hospital of Stomatology, National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu, China
- Division of Oral Biology, Tufts University School of Dental Medicine, Boston, MA, United States
| | - Wei Qiu
- Department of Stomatology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Xiaofang Zhu
- Division of Oral Biology, Tufts University School of Dental Medicine, Boston, MA, United States
- Department of Periodontology, Tufts University School of Dental Medicine, Boston, MA, United States
| | - Xiangfen Li
- State Key Laboratory of Oral Disease, West China Hospital of Stomatology, National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu, China
| | - Zhongcong Xie
- Geriatric Anesthesia Research Unit, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States
| | - Isabel Carreras
- Department of Veterans Affairs, VA Boston Healthcare System, Boston, MA, United States
- Department of Neurology and Department of Biochemistry School of Medicine, Boston University, Boston, MA, United States
| | - Alpaslan Dedeoglu
- Department of Veterans Affairs, VA Boston Healthcare System, Boston, MA, United States
- Department of Neurology School of Medicine, Boston University, Boston, MA, United States
| | - Thomas Van Dyke
- The Forsyth Institute, Clinical and Translational Research, Cambridge, MA, United States
- Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, United States
| | - Yiping W. Han
- Section of Oral, Diagnostic and Rehabilitation Sciences, College of Dental Medicine, University Irvign Medical Center, New York, NY, United States
- Department of Microbiology & Immunology, Vagelos College of Physicians & Surgeons, Columbia University Irvign Medical Center, New York, NY, United States
| | - Nadeem Karimbux
- Department of Periodontology, Tufts University School of Dental Medicine, Boston, MA, United States
| | - Qisheng Tu
- Division of Oral Biology, Tufts University School of Dental Medicine, Boston, MA, United States
- Department of Periodontology, Tufts University School of Dental Medicine, Boston, MA, United States
| | - Lei Cheng
- State Key Laboratory of Oral Disease, West China Hospital of Stomatology, National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu, China
| | - Jake Chen
- Division of Oral Biology, Tufts University School of Dental Medicine, Boston, MA, United States
- Department of Periodontology, Tufts University School of Dental Medicine, Boston, MA, United States
- Department of Developmental, Molecular and Chemical Biology, Tufts University School of Medicine, Boston, MA, United States
- Graduate School of Biomedical Sciences, Tufts University, Boston, MA, United States
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Lima MN, Barbosa-Silva MC, Maron-Gutierrez T. Microglial Priming in Infections and Its Risk to Neurodegenerative Diseases. Front Cell Neurosci 2022; 16:878987. [PMID: 35783096 PMCID: PMC9240317 DOI: 10.3389/fncel.2022.878987] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 04/26/2022] [Indexed: 11/29/2022] Open
Abstract
Infectious diseases of different etiologies have been associated with acute and long-term neurological consequences. The primary cause of these consequences appears to be an inflammatory process characterized primarily by a pro-inflammatory microglial state. Microglial cells, the local effectors' cells of innate immunity, once faced by a stimulus, alter their morphology, and become a primary source of inflammatory cytokines that increase the inflammatory process of the brain. This inflammatory scenario exerts a critical role in the pathogenesis of neurodegenerative diseases. In recent years, several studies have shown the involvement of the microglial inflammatory response caused by infections in the development of neurodegenerative diseases. This has been associated with a transitory microglial state subsequent to an inflammatory response, known as microglial priming, in which these cells are more responsive to stimuli. Thus, systemic inflammation and infections induce a transitory state in microglia that may lead to changes in their state and function, making priming them for subsequent immune challenges. However, considering that microglia are long-lived cells and are repeatedly exposed to infections during a lifetime, microglial priming may not be beneficial. In this review, we discuss the relationship between infections and neurodegenerative diseases and how this may rely on microglial priming.
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Affiliation(s)
- Maiara N. Lima
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Fiocruz, Rio de Janeiro, Brazil
| | - Maria C. Barbosa-Silva
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Fiocruz, Rio de Janeiro, Brazil
| | - Tatiana Maron-Gutierrez
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Fiocruz, Rio de Janeiro, Brazil
- National Institute of Science and Technology on Neuroimmunomodulation, Rio de Janeiro, Brazil
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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.
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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.
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50
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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.
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