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Wang Q, Zhen W, Hu R, Wang Z, Sun Y, Sun W, Huang C, Xu J, Zhang H. Occlusion dysfunction and Alzheimer's disease: Mendelian randomization study. Front Aging Neurosci 2024; 16:1423322. [PMID: 39035234 PMCID: PMC11258003 DOI: 10.3389/fnagi.2024.1423322] [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: 04/25/2024] [Accepted: 06/20/2024] [Indexed: 07/23/2024] Open
Abstract
Aim Occlusion dysfunction (OD) is increasingly linked to Alzheimer's disease (AD). This study aimed to elucidate the causal relationship between OD and AD using Mendelian randomization (MR) analysis. Materials and methods Genome-wide association study (GWAS) meta-analysis data obtained from FinnGen, IEU Open GWAS, and UK Biobank (UKBB) was represented as instrumental variables. We validated the causal relationship between periodontal disease (PD), loose teeth (PD & occlusion dysfunction), dentures restoration (occlusion recovery), and AD. Results According to the MR analysis, PD and AD have no direct causal relationship (P = 0.395, IVW). However, loose teeth significantly increased the risk of AD progression (P = 0.017, IVW, OR = 187.3567, 95%CI = 2.54E+00-1.38E+04). These findings were further supported by the negative causal relationship between dentures restoration and AD (P = 0.015, IVW, OR = 0.0234, 95%CI = 1.13E-03-0.485). Conclusion The occlusion dysfunction can ultimately induce Alzheimer's disease. Occlusion function was a potentially protective factor for maintaining neurological health.
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Affiliation(s)
- Qing Wang
- Key Laboratory of Oral Diseases Research of Anhui Province, College and Hospital of Stomatology, Anhui Medical University, Hefei, China
| | - Wenyu Zhen
- Key Laboratory of Oral Diseases Research of Anhui Province, College and Hospital of Stomatology, Anhui Medical University, Hefei, China
| | - Rui Hu
- Department of Anesthesiology and Perioperative Medicine, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Zifei Wang
- Key Laboratory of Oral Diseases Research of Anhui Province, College and Hospital of Stomatology, Anhui Medical University, Hefei, China
| | - Yuqiang Sun
- Key Laboratory of Oral Diseases Research of Anhui Province, College and Hospital of Stomatology, Anhui Medical University, Hefei, China
| | - Wansu Sun
- Department of Stomatology, Anhui Public Health Clinical Center, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Chunxia Huang
- Department of Anesthesiology and Perioperative Medicine, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Jianguang Xu
- Key Laboratory of Oral Diseases Research of Anhui Province, College and Hospital of Stomatology, Anhui Medical University, Hefei, China
| | - Hengguo Zhang
- Key Laboratory of Oral Diseases Research of Anhui Province, College and Hospital of Stomatology, Anhui Medical University, Hefei, China
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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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Fujiwara A, Fukunaga A, Murakami K, Inoue Y, Nakagawa T, Yamamoto S, Konishi M, Mizoue T. Association between Dietary Hardness and Cognitive Dysfunction among Japanese Men in Their 60s: A Cross-Sectional Study. Nutrients 2023; 15:nu15112485. [PMID: 37299449 DOI: 10.3390/nu15112485] [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: 03/08/2023] [Revised: 05/06/2023] [Accepted: 05/23/2023] [Indexed: 06/12/2023] Open
Abstract
We aimed to examine the cross-sectional association between dietary hardness and cognitive dysfunction among Japanese men in their 60s. Participants were 1494 men aged 60-69 years from the baseline survey of Hitachi Health Study II (2017-2020). Dietary hardness was defined as an estimate of masticatory muscle activity involved in consuming solid foods. Habitual intake of these foods was assessed using a brief-type, self-administered diet history questionnaire. Cognitive dysfunction was defined as a score ≤ 13 points on the test battery for screening for Alzheimer's disease (MSP-1100). The mean (SD) age of participants was 63.5 (3.5) years. The prevalence of cognitive dysfunction was 7.5%. The ORs (95% CIs) for cognitive dysfunction in the second and third tertiles were: 0.77 (0.47, 1.26) and 0.87 (0.54, 1.41), respectively, after adjustment for socio-demographic factors (p for trend = 0.73). After further adjustment for protective nutrient intake against cognitive dysfunction, the corresponding figures were 0.72 (0.43, 1.21) and 0.79 (0.43, 1.46), respectively (p for trend = 0.57). Dietary hardness was not associated with the prevalence of cognitive dysfunction among Japanese men in their 60s. Future prospective studies are necessary to investigate the association between dietary hardness estimated by a validated questionnaire and cognitive dysfunctions.
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Affiliation(s)
- Aya Fujiwara
- Department of Epidemiology and Prevention, Center for Clinical Sciences, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo 162-8655, Japan
- Department of Social and Preventive Epidemiology, School of Public Health, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Department of Nutritional Epidemiology and Shokuiku, National Institutes of Biomedical Innovation, Health and Nutrition, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8636, Japan
| | - Ami Fukunaga
- Department of Epidemiology and Prevention, Center for Clinical Sciences, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Kentaro Murakami
- Department of Social and Preventive Epidemiology, School of Public Health, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yosuke Inoue
- Department of Epidemiology and Prevention, Center for Clinical Sciences, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Tohru Nakagawa
- Hitachi Health Care Center, Hitachi, Ltd., 4-3-16 Osecho, Hitachi-shi 317-0076, Ibaraki, Japan
| | - Shuichiro Yamamoto
- Hitachi Health Care Center, Hitachi, Ltd., 4-3-16 Osecho, Hitachi-shi 317-0076, Ibaraki, Japan
| | - Maki Konishi
- Department of Epidemiology and Prevention, Center for Clinical Sciences, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Tetsuya Mizoue
- Department of Epidemiology and Prevention, Center for Clinical Sciences, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo 162-8655, Japan
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Al-Manei K, Jia L, Al-Manei KK, Ndanshau EL, Grigoriadis A, Kumar A. Food Hardness Modulates Behavior, Cognition, and Brain Activation: A Systematic Review of Animal and Human Studies. Nutrients 2023; 15:nu15051168. [PMID: 36904167 PMCID: PMC10005610 DOI: 10.3390/nu15051168] [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: 01/31/2023] [Revised: 02/22/2023] [Accepted: 02/23/2023] [Indexed: 03/02/2023] Open
Abstract
Food hardness is one of the dietary features that may impact brain functions. We performed a systematic review to evaluate the effect of food hardness (hard food versus soft food diet) on behavior, cognition, and brain activation in animals and humans (PROSPERO ID: CRD42021254204). The search was conducted on 29 June 2022 using Medline (Ovid), Embase, and Web of Science databases. Data were extracted, tabulated by food hardness as an intervention, and summarized by qualitative synthesis. The SYRCLE and JBI tools were used to assess the risk of bias (RoB) of individual studies. Of the 5427 studies identified, 18 animal studies and 6 human studies met the inclusion criteria and were included. The RoB assessment indicated that 61% of animal studies had unclear risks, 11% had moderate risks, and 28% had low risks. All human studies were deemed to have a low risk of bias. The majority (48%) of the animal studies showed that a hard food diet improved behavioral task performance compared to soft food diets (8%). However, 44% of studies also showed no differential effects of food hardness on behavioral tests. It was also evident that certain regions of the brain were activated in response to changes in food hardness in humans, with a positive association between chewing hard food, cognition performance, and brain function. However, variations in the methodologies of the included studies hindered the meta-analysis execution. In conclusion, our findings highlight the beneficial effects of dietary food hardness on behavior, cognition, and brain function in both animals and humans, however, this effect may depend on several factors that require further understanding of the causality.
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Affiliation(s)
- Khaled Al-Manei
- Division of Oral Diagnostics and Rehabilitation, Department of Dental Medicine, Karolinska Institutet, 141 04 Huddinge, Sweden
- Division of Endodontics, Department of Restorative Dental Science, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia
| | - Leming Jia
- Division of Oral Diagnostics and Rehabilitation, Department of Dental Medicine, Karolinska Institutet, 141 04 Huddinge, Sweden
| | - Kholod Khalil Al-Manei
- Division of Endodontics, Department of Restorative Dental Science, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia
| | | | - Anastasios Grigoriadis
- Division of Oral Diagnostics and Rehabilitation, Department of Dental Medicine, Karolinska Institutet, 141 04 Huddinge, Sweden
| | - Abhishek Kumar
- Division of Oral Diagnostics and Rehabilitation, Department of Dental Medicine, Karolinska Institutet, 141 04 Huddinge, Sweden
- Academic Center for Geriatric Dentistry, 112 19 Stockholm, Sweden
- Correspondence:
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de Siqueira Mendes FDCC, Paixão LTVB, Diniz DG, Anthony DC, Brites D, Diniz CWP, Sosthenes MCK. Sedentary Life and Reduced Mastication Impair Spatial Learning and Memory and Differentially Affect Dentate Gyrus Astrocyte Subtypes in the Aged Mice. Front Neurosci 2021; 15:632216. [PMID: 33935629 PMCID: PMC8081835 DOI: 10.3389/fnins.2021.632216] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 03/03/2021] [Indexed: 11/13/2022] Open
Abstract
To explore the impact of reduced mastication and a sedentary lifestyle on spatial learning and memory in the aged mice, as well as on the morphology of astrocytes in the molecular layer of dentate gyrus (MolDG), different masticatory regimens were imposed. Control mice received a pellet-type hard diet, while the reduced masticatory activity group received a pellet diet followed by a powdered diet, and the masticatory rehabilitation group received a pellet diet, followed by powder diet and then a pellet again. To mimic sedentary or active lifestyles, mice were housed in an impoverished environment of standard cages or in an enriched environment. The Morris Water Maze (MWM) test showed that masticatory-deprived group, regardless of environment, was not able to learn and remember the hidden platform location, but masticatory rehabilitation combined with enriched environment recovered such disabilities. Microscopic three-dimensional reconstructions of 1,800 glial fibrillary acidic protein (GFAP)-immunolabeled astrocytes from the external third of the MolDG were generated using a stereological systematic and random sampling approach. Hierarchical cluster analysis allowed the characterization into two main groups of astrocytes with greater and lower morphological complexities, respectively, AST1 and AST2. When compared to compared to the hard diet group subjected to impoverished environment, deprived animals maintained in the same environment for 6 months showed remarkable shrinkage of astrocyte branches. However, the long-term environmental enrichment (18-month-old) applied to the deprived group reversed the shrinkage effect, with significant increase in the morphological complexity of AST1 and AST2, when in an impoverished or enriched environment. During housing under enriched environment, complexity of branches of AST1 and AST2 was reduced by the powder diet (pellet followed by powder regimes) in young but not in old mice, where it was reversed by pellet diet (pellet followed by powder and pellet regime again). The same was not true for mice housed under impoverished environment. Interestingly, we were unable to find any correlation between MWM data and astrocyte morphological changes. Our findings indicate that both young and aged mice subjected to environmental enrichment, and under normal or rehabilitated masticatory activity, preserve spatial learning and memory. Nonetheless, data suggest that an impoverished environment and reduced mastication synergize to aggravate age-related cognitive decline; however, the association with morphological diversity of AST1 and AST2 at the MolDG requires further investigation.
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Affiliation(s)
- Fabíola de Carvalho Chaves de Siqueira Mendes
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil.,Curso de Medicina, Centro Universitário do Estado do Pará, Belém, Brazil
| | - Luisa Taynah Vasconcelos Barbosa Paixão
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
| | - Daniel Guerreiro Diniz
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil.,Laboratório de Microscopia Eletrônica, Instituto Evandro Chagas, Belém, Brazil
| | - Daniel Clive Anthony
- Laboratory of Experimental Neuropathology, Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Dora Brites
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal.,Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - Cristovam Wanderley Picanço Diniz
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
| | - Marcia Consentino Kronka Sosthenes
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
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6
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Nakamura T, Zou K, Shibuya Y, Michikawa M. Oral dysfunctions and cognitive impairment/dementia. J Neurosci Res 2020; 99:518-528. [PMID: 33164225 DOI: 10.1002/jnr.24745] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 10/01/2020] [Accepted: 10/04/2020] [Indexed: 01/11/2023]
Abstract
With global increases in the aging population, the number of patients with dementia is greatly increasing, which has become a big social problem. Many studies have shown strong associations between oral disorders and systemic disorders, such as diabetes, arthritis, sepsis, aspiration pneumonia, arteriosclerosis, bacterial endocarditis, and other cardiovascular diseases. Similarly, numerous cross-sectional studies showed that patients with dementia usually have poor oral conditions and tooth loss. These have long been considered as a result of difficulty with oral care due to impaired cognitive function, memory, and physical ability in patients with dementia. Indeed, even in patients with mild cognitive impairment, oral care becomes insufficient owing to decreases in spontaneity of grooming and finger dexterity. However, recent studies have shown that tooth loss and occlusal dysfunction may affect brain function and trigger the onset of dementia found in neurodegenerative diseases including Alzheimer's disease. In this review, we highlight the relationships among aging, oral dysfunction, and the development of dementia. Increasing evidence suggests that oral dysfunction is not only a result of dementia in the elderly people, but could also be a causative factor for the onset of dementia.
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Affiliation(s)
- Tomohisa Nakamura
- Department of Biochemistry, Nagoya City University, Graduate School of Medical Sciences, Nagoya, Japan.,Maxillofacial Surgery, Nagoya City University, Graduate School of Medical Sciences, Nagoya, Japan
| | - Kun Zou
- Department of Biochemistry, Nagoya City University, Graduate School of Medical Sciences, Nagoya, Japan
| | - Yasuyuki Shibuya
- Maxillofacial Surgery, Nagoya City University, Graduate School of Medical Sciences, Nagoya, Japan
| | - Makoto Michikawa
- Department of Biochemistry, Nagoya City University, Graduate School of Medical Sciences, Nagoya, Japan
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Memory impairment of chewing-side preference mice is associated with 5-HT-BDNF signal pathway. Mol Cell Biochem 2020; 476:303-310. [PMID: 32989626 DOI: 10.1007/s11010-020-03907-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 09/07/2020] [Indexed: 01/13/2023]
Abstract
Although tooth loss is a known risk factor of cognitive function, whether and how the chewing-side preference (CSP) affects memory impairment still remains unclear. This study evaluates the behavior changes in mice after the loss of teeth on one side and explores the role of serotonin (5-HT) and brain-derived neurotrophic factor (BDNF) signal pathway within these changes. To this end, CSP mouse models with either the removal of left unilateral molars (CSP-L) or right unilateral molars (CSP-R) were established. Morris water maze test and passive avoidance test were performed to evaluate the mice's learning and memory capacity in the 4th and 8th weeks. The correlation between CSP and brain function changes was validated with changes in 5-HT and BDNF levels. CSP mice's cognitive function was found to be decreased, along with a significant decline in 5-HT1A level, especially in CSP-R mice. BDNF and TrkB levels in CSP-R mice were also significantly lowered. These findings suggest that CSP results in memory impairment, which is associated with the 5-HT-BDNF signaling pathway.
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Horvath KC, Miller-Cushon EK. Effects of hay provision and presentation on cognitive development in dairy calves. PLoS One 2020; 15:e0238038. [PMID: 32870925 PMCID: PMC7462293 DOI: 10.1371/journal.pone.0238038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 08/07/2020] [Indexed: 12/22/2022] Open
Abstract
In the dairy industry, feeding management has considerable influence on calf behavioral development, yet there is limited understanding of how aspects of diet or accommodating more varied feeding behavior may affect cognitive development in young calves. The objective of this study was to evaluate effects of provision and presentation of hay on the cognitive ability of pre-weaned dairy calves. Individually-housed Holstein heifer calves were assigned at birth to 1 of 3 treatments: pelleted starter only (n = 10), hay (chopped to 5 cm) and starter provided in separate buckets (n = 12), or hay and starter offered as a mixture (n = 11). During week 5 of age, calves were tested daily in a learning task consisting of a T-maze with a milk reward (0.2 L milk) placed in one arm. Calves were subjected to an initial learning and reversal learning stage, where the reward location was changed to the opposite arm of the maze. Calves received 5 sessions/d until they met learning criterion (moving directly to correct side in 3 consecutive sessions) for initial and reversal learning. Dietary treatment did not affect pass rate or the number of sessions required to pass the initial learning stage. During the reversal learning stage, calves provided only starter had a lower pass rate (0.038, during first 8 testing session) early during testing than calves provided hay separately (0.20; P = 0.020) and tended to have a lower pass rate than calves provided hay as a mixture (0.14; P = 0.057). Calves provided only starter also tended to require more sessions to meet the learning criterion (15.8) than both calves provided hay separately (10.8; P = 0.089) and as a mixture (11.8; P = 0.10). Calves provided hay also kicked less and spent more time sniffing or licking the testing area. The results of this experiment indicate that provision of hay may affect behavioral flexibility in dairy calves.
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Affiliation(s)
- Kelsey C. Horvath
- Department of Animal Sciences, University of Florida, Gainesville, Florida, United States of America
| | - Emily K. Miller-Cushon
- Department of Animal Sciences, University of Florida, Gainesville, Florida, United States of America
- * E-mail:
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Han JH, Lee HJ, Han JW, Suh SW, Lee JR, Byun S, Kim KS, Kim SY, Lee JT, Yoo E, Chang NH, Kim TH, Kim KW. Loss of Functional Dentition is Associated with Cognitive Impairment. J Alzheimers Dis 2020; 73:1313-1320. [PMID: 31929161 DOI: 10.3233/jad-190971] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Although tooth loss is known to increase the risk of cognitive impairment and dementia, few studies have investigated the association between functional teeth including rehabilitated lost teeth and cognitive functionObjective:We investigated the associations of the numbers of functional teeth and functional occlusal units with cognitive impairment and cognitive function in late life. METHODS The current study was conducted as a part of the Korean Longitudinal Study on Cognitive Aging and Dementia (KLOSCAD), a community-based elderly cohort study. We analyzed 411 participants who have agreed with the additional dental exam. Geriatric psychiatrists and neuropsychologists administered the Consortium to Establish a Registry for Alzheimer's disease Assessment Packet Clinical and Neuropsychological Assessment Battery to all participants, and dentists examined their dental status. RESULTS Higher number of functional teeth (OR = 0.955, 95% CI = 0.914-0.997, p = 0.037) and higher number of functional occlusal units (OR = 0.900, 95% CI = 0.813-0.996, p = 0.042) were associated with lower odds of cognitive impairment. When we analyzed these relationships separated by the location of teeth, only the numbers of functional teeth (OR = 0.566, 95% CI = 0.373-0.857, p = 0.007) and functional occlusal units (OR = 0.399, 95% CI = 0.213-0.748, p = 0.004) in the premolar area were associated with lower odds of cognitive impairment. CONCLUSION Loss of functional teeth and functional occlusal units (especially in the premolar region) were associated with increased cognitive impairment.
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Affiliation(s)
- Ji Hyun Han
- Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Hyo-Jung Lee
- Department of Periodontology, Section of Dentistry, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Ji Won Han
- Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Seung Wan Suh
- Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, Korea
| | | | - Seonjeong Byun
- Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Keun Suh Kim
- Department of Periodontology, Section of Dentistry, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Sung Yeol Kim
- Department of Periodontology, Section of Dentistry, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Jung-Tae Lee
- Department of Periodontics, Dankook University College of Dentistry Jukjeon Dental Hospital, Yongin, Korea
| | - Eunha Yoo
- Section of Dentistry, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Na-Hee Chang
- Biomedical Research Institute, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Tae Hui Kim
- Department of Psychiatry, Yonsei University Wonju Severance Christian Hospital, Wonju, Korea
| | - Ki Woong Kim
- Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, Korea.,Department of Psychiatry, Seoul National University, College of Medicine, Seoul, Korea.,Department of Brain and Cognitive Science, Seoul National University College of Natural Sciences, Seoul, Korea.,National Institute of Dementia, Seongnam, Korea
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Adedayo BC, Ogunsuyi OB, Akinniyi ST, Oboh G. Effect ofAndrographis paniculataandPhyllanthus amarusleaf extracts on selected biochemical indices inDrosophila melanogastermodel of neurotoxicity. Drug Chem Toxicol 2020; 45:407-416. [DOI: 10.1080/01480545.2019.1708377] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Bukola Christiana Adedayo
- Functional Foods and Nutraceuticals Unit of Biochemistry Department, Federal University of Technology, Akure, Nigeria
| | - Opeyemi Babatunde Ogunsuyi
- Functional Foods and Nutraceuticals Unit of Biochemistry Department, Federal University of Technology, Akure, Nigeria
- Department of Biomedical Technology, Federal University of Technology, Akure, Nigeria
| | - Stephanie Tolulope Akinniyi
- Functional Foods and Nutraceuticals Unit of Biochemistry Department, Federal University of Technology, Akure, Nigeria
| | - Ganiyu Oboh
- Functional Foods and Nutraceuticals Unit of Biochemistry Department, Federal University of Technology, Akure, Nigeria
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Bumb S, Govindan CC, Kadtane S, JN R, Chawla R, Gupta R. Association between Cognitive Decline and Oral Health Status in the Aging Population : A 5- year Observational study (Preprint). JMIR Aging 2019. [DOI: 10.2196/15221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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12
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Effect of Antibodies to Glutamate on Age-Related Memory Changes in C57Bl/6 Mice. Bull Exp Biol Med 2019; 166:326-329. [PMID: 30627908 DOI: 10.1007/s10517-019-04343-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Indexed: 10/27/2022]
Abstract
Chronic intranasal administration of antibodies to glutamate to aging C57Bl/6 mice improved passive avoidance conditioning, had no effect on horizontal and vertical locomotor activity, but slowed locomotion in the open-field test. Administration of antibodies to glutamate increased the content of dopamine and its metabolites in mouse hippocampus, but had no effect on the metabolism of neurotransmitter amino acids. In the frontal cortex, antibodies to glutamate did not affect neurotransmitter metabolism, but increased the level of both excitatory and inhibitory amino acids without changing their ratio.
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13
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Yaoita F, Tsuchiya M, Arai Y, Tadano T, Tan-No K. Involvement of catecholaminergic and GABAAergic mediations in the anxiety-related behavior in long-term powdered diet-fed mice. Neurochem Int 2018; 124:1-9. [PMID: 30529642 DOI: 10.1016/j.neuint.2018.12.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 11/30/2018] [Accepted: 12/04/2018] [Indexed: 11/26/2022]
Abstract
Dietary habits are important factors which affect metabolic homeostasis and the development of emotion. We have previously shown that long-term powdered diet feeding in mice increases spontaneous locomotor activity and social interaction (SI) time. Moreover, that diet causes changes in the dopaminergic system, especially increased dopamine turnover and decreased dopamine D4 receptor signals in the frontal cortex. Although the increased SI time indicates low anxiety, the elevated plus maze (EPM) test shows anxiety-related behavior and impulsive behavior. In this study, we investigated whether the powdered diet feeding causes changes in anxiety-related behavior. Mice fed a powdered diet for 17 weeks from weaning were compared with mice fed a standard diet (control). The percentage (%) of open arm time and total number of arm entries were increased in powdered diet-fed mice in the EPM test. We also examined the effects of diazepam, benzodiazepine anti-anxiety drug, bicuculline, GABA-A receptor antagonist, methylphenidate, dopamine transporter (DAT) and noradrenaline transporter (NAT) inhibitor, atomoxetine, selective NAT inhibitor, GBR12909, selective DAT inhibitor, and PD168077, selective dopamine D4 receptor agonist, on the changes of the EPM in powdered diet-fed mice. Methylphenidate and atomoxetine are clinically used to treat attention deficit/hyperactivity disorder (ADHD) symptoms. The % of open arm time in powdered diet-fed mice was decreased by treatments of atomoxetine, methylphenidate and PD168077. Diazepam increased the % of open arm time in control diet-fed mice, but not in powdered diet-fed mice. The powdered diet feeding induced a decrease in GABA transaminase, GABA metabolic enzymes, in the frontal cortex. Moreover, the powdered diet feeding induced an increase in NAT expression, but not DAT expression, in the frontal cortex. These results suggest that the long-term powdered diet feeding may cause low anxiety or impulsivity, possibly via noradrenergic and/or dopaminergic, and GABAAergic mediations and increase the risk for onset of ADHD-like behaviors.
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Affiliation(s)
- Fukie Yaoita
- Department of Pharmacology, Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai, 981-8558, Japan.
| | - Masahiro Tsuchiya
- Department of Nursing, Tohoku Fukushi University, 1-8-1 Kunimi, Aoba-ku, Sendai, 981-8522, Japan
| | - Yuichiro Arai
- Tokyo Ariake University of Medical and Health Science, 2-9-1 Ariake, Koto-Ku, Tokyo, 135-0063, Japan
| | - Takeshi Tadano
- Complementary and Alternative Medicine Clinical Research and Development, Graduate School of Medicine Sciences, Kanazawa University, Kakumamachi, Kanazawa, 920-1192, Japan
| | - Koichi Tan-No
- Department of Pharmacology, Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai, 981-8558, Japan
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14
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Okubo H, Murakami K, Inagaki H, Gondo Y, Ikebe K, Kamide K, Masui Y, Arai Y, Ishizaki T, Sasaki S, Nakagawa T, Kabayama M, Sugimoto K, Rakugi H, Maeda Y. Hardness of the habitual diet and its relationship with cognitive function among 70-year-old Japanese elderly: Findings from the SONIC Study. J Oral Rehabil 2018; 46:151-160. [PMID: 30325532 DOI: 10.1111/joor.12731] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 09/28/2018] [Accepted: 10/08/2018] [Indexed: 11/28/2022]
Abstract
BACKGROUND There is increasing evidence of causal links between poor mastication and cognitive impairment, but possible effects of dietary hardness, which clearly affects mastication, on cognitive function are unknown. OBJECTIVE We investigated the hypothesis that hardness of the habitual diet would be associated with cognitive function among older Japanese adults. METHODS The subjects of this cross-sectional study were 635 Japanese community-dwelling people aged 69-71 years. The masticatory muscle activity required for the habitual diet was used to determine dietary hardness. Consumption of 38 foods was assessed by a validated, brief-type, self-administered diet history questionnaire. A published database was then used to estimate the masticatory muscle activity involved in the ingestion of these foods. The Japanese version of the Montreal Cognitive Assessment (MoCA-J) was used for the measurement of cognitive function. RESULTS The principal contributors to dietary hardness were cooked rice (28.0%), green leafy vegetables (5.1%), dried fish (4.9%), and pork and beef (4.6%). There was a positive association between dietary hardness and MoCA-J score that was robust to adjustment for potential confounders (MoCA-J score per 100-unit increase in dietary hardness: β = 0.83 [95% CI: 0.08, 1.59], P = 0.03). These results did not change materially even after exclusion of subjects who reported substantial changes in their diet for any reason (β = 0.94 [95% CI: 0.02, 1.86], P = 0.04). CONCLUSION This preliminary cross-sectional study suggests that dietary hardness might have a beneficial effect on cognitive function in older Japanese people. Further prospective studies with more accurate measurements are needed to confirm this finding.
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Affiliation(s)
- Hitomi Okubo
- Department of Health Promotion, National Institute of Public Health, Saitama, Japan
| | - Kentaro Murakami
- Department of Social and Preventive Epidemiology, School of Public Health, University of Tokyo, Tokyo, Japan
| | - Hiroki Inagaki
- Tokyo Metropolitan Geriatric Hospital and Institute of Gerontology, Tokyo, Japan
| | - Yasuyuki Gondo
- Department of Clinical Thanatology and Geriatric Behavioral Science, Osaka University Graduate School of Human Sciences, Osaka, Japan
| | - Kazunori Ikebe
- Department of Prosthodontics, Gerontology and Oral Rehabilitation, Osaka University Graduate School of Dentistry, Osaka, Japan
| | - Kei Kamide
- Department of Health Science, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Yukie Masui
- Tokyo Metropolitan Geriatric Hospital and Institute of Gerontology, Tokyo, Japan
| | - Yasumichi Arai
- Center for Supercentenarian Medical Research, Keio University, School of Medicine, Tokyo, Japan
| | - Tatsuro Ishizaki
- Tokyo Metropolitan Geriatric Hospital and Institute of Gerontology, Tokyo, Japan
| | - Satoshi Sasaki
- Department of Social and Preventive Epidemiology, School of Public Health, University of Tokyo, Tokyo, Japan
| | - Takeshi Nakagawa
- National Center for Geriatrics and Gerontology, Aichi, Japan.,Japan Society for the Promotion of Science, Tokyo, Japan
| | - Mai Kabayama
- Department of Health Science, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Ken Sugimoto
- Department of Geriatric and General Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Hiromi Rakugi
- Department of Geriatric and General Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Yoshinobu Maeda
- Department of Prosthodontics, Gerontology and Oral Rehabilitation, Osaka University Graduate School of Dentistry, Osaka, Japan
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15
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Saito S, Ohi T, Murakami T, Komiyama T, Miyoshi Y, Endo K, Satoh M, Asayama K, Inoue R, Kikuya M, Metoki H, Imai Y, Ohkubo T, Hattori Y. Association between tooth loss and cognitive impairment in community-dwelling older Japanese adults: a 4-year prospective cohort study from the Ohasama study. BMC Oral Health 2018; 18:142. [PMID: 30126407 PMCID: PMC6102919 DOI: 10.1186/s12903-018-0602-7] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 08/03/2018] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Numerous prospective studies have investigated the association between the number of remaining teeth and dementia or cognitive decline. However, no agreement has emerged on the association between tooth loss and cognitive impairment, possibly due to past studies differing in target groups and methodologies. We aimed to investigate the association between tooth loss, as evaluated through clinical oral examinations, and the development of cognitive impairment in community-dwelling older adults while considering baseline cognitive function. METHODS This 4-year prospective cohort study followed 140 older adults (69.3% female) without cognitive impairment aged ≥65 years (mean age: 70.9 ± 4.3 years) living in the town of Ohasama, Iwate Prefecture, Japan. Cognitive function was evaluated with the Mini-Mental State Examination (MMSE) in baseline and follow-up surveys. Based on a baseline oral examination, the participants were divided into those with 0-9 teeth and those with ≥10 teeth. To investigate the association between tooth loss and cognitive impairment, we applied a multiple logistic regression analysis adjusted for age, sex, hypertension, diabetes, cerebrovascular/cardiovascular disease, hypercholesterolemia, depressive symptoms, body mass index, smoking status, drinking status, duration of education, and baseline MMSE score. RESULTS In the 4 years after the baseline survey, 27 participants (19.3%) developed cognitive impairment (i.e., MMSE scores of ≤24). Multiple logistic regression analysis indicated that participants with 0-9 teeth were more likely to develop cognitive impairment than those with ≥10 teeth were (odds ratio: 3.31; 95% confidence interval: 1.07-10.2). Age, male gender, and baseline MMSE scores were also significantly associated with cognitive impairment. CONCLUSIONS Tooth loss was independently associated with the development of cognitive impairment within 4 years among community-dwelling older adults. This finding corroborates the hypothesis that tooth loss may be a predictor or risk factor for cognitive decline.
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Affiliation(s)
- Sho Saito
- Division of Aging and Geriatric Dentistry, Department of Oral Function and Morphology, Tohoku University Graduate School of Dentistry, 4-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575 Japan
| | - Takashi Ohi
- Division of Aging and Geriatric Dentistry, Department of Oral Function and Morphology, Tohoku University Graduate School of Dentistry, 4-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575 Japan
- Japanese Red Cross Ishinomaki Hospital, Ishinomaki, Japan
| | - Takahisa Murakami
- Division of Public Health, Hygiene and Epidemiology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Takamasa Komiyama
- Division of Aging and Geriatric Dentistry, Department of Oral Function and Morphology, Tohoku University Graduate School of Dentistry, 4-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575 Japan
| | - Yoshitada Miyoshi
- Division of Aging and Geriatric Dentistry, Department of Oral Function and Morphology, Tohoku University Graduate School of Dentistry, 4-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575 Japan
| | - Kosei Endo
- Division of Aging and Geriatric Dentistry, Department of Oral Function and Morphology, Tohoku University Graduate School of Dentistry, 4-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575 Japan
| | - Michihiro Satoh
- Division of Public Health, Hygiene and Epidemiology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Kei Asayama
- Department of Hygiene and Public Health, Teikyo University School of Medicine, Tokyo, Japan
- Department of Planning for Drug Development and Clinical Evaluation, Tohoku University Graduate School of Pharmaceutical Sciences, Sendai, Japan
| | - Ryusuke Inoue
- Department of Medical Informatics, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Masahiro Kikuya
- Department of Preventive Medicine and Epidemiology, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan
| | - Hirohito Metoki
- Division of Public Health, Hygiene and Epidemiology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Yutaka Imai
- Department of Planning for Drug Development and Clinical Evaluation, Tohoku University Graduate School of Pharmaceutical Sciences, Sendai, Japan
| | - Takayoshi Ohkubo
- Department of Hygiene and Public Health, Teikyo University School of Medicine, Tokyo, Japan
| | - Yoshinori Hattori
- Division of Aging and Geriatric Dentistry, Department of Oral Function and Morphology, Tohoku University Graduate School of Dentistry, 4-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575 Japan
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16
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Jou YT. Dental deafferentation and brain damage: A review and a hypothesis. Kaohsiung J Med Sci 2018; 34:231-237. [PMID: 29655412 DOI: 10.1016/j.kjms.2018.01.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 12/07/2017] [Accepted: 01/12/2018] [Indexed: 01/04/2023] Open
Abstract
In the last few decades, neurobiological and human brain imaging research have greatly advanced our understanding of brain mechanisms that support perception and memory, as well as their function in daily activities. Knowledge of the neurobiological mechanisms behind the deafferentation of stomatognathic systems has also expanded greatly in recent decades. In particular, current studies reveal that the peripheral deafferentations of stomatognathic systems may be projected globally into the central nervous system (CNS) and become an associated critical factor in triggering and aggravating neurodegenerative diseases. This review explores basic neurobiological mechanisms associated with the deafferentation of stomatognathic systems. Further included is a discussion on tooth loss and other dental deafferentation (DD) mechanisms, with a focus on dental and masticatory apparatuses associated with brain functions and which may underlie the changes observed in the aging brain. A new hypothesis is presented where DD and changes in the functionality of teeth and the masticatory apparatus may cause brain damage as a result of altered cerebral circulation and dysfunctional homeostasis. Furthermore, multiple recurrent reorganizations of the brain may be a triggering or contributing risk factor in the onset and progression of neurodegenerative conditions such as Alzheimer's disease (AD). A growing understanding of the association between DD and brain aging may lead to solutions in treating and preventing cognitive decline and neurodegenerative diseases.
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Affiliation(s)
- Yi-Tai Jou
- Department of Endodontics School of Dental Medicine University of Pennsylvania Philadelphia, Pennsylvania, USA.
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17
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Kim D, Chung S, Lee SH, Choi SY, Kim SM, Koo J, Lee JH, Jahng JW. Decreased hippocampal brain-derived neurotrophic factor and impaired cognitive function by hypoglossal nerve transection in rats. J Cell Mol Med 2017; 21:3752-3760. [PMID: 28767193 PMCID: PMC5706565 DOI: 10.1111/jcmm.13284] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 05/22/2017] [Indexed: 12/21/2022] Open
Abstract
The hypoglossal nerve controls tongue movements, and damages of it result in difficulty in mastication and food intake. Mastication has been reported to maintain hippocampus‐dependent cognitive function. This study was conducted to examine the effect of tongue motor loss on the hippocampus‐dependent cognitive function and its underlying mechanism. Male Sprague Dawley rats were subjected to the initial training of Morris water maze task before or after the bilateral transection of hypoglossal nerves (Hx). When the initial training was given before the surgery, the target quadrant dwelling time during the probe test performed at a week after the surgery was significantly reduced in Hx rats relative to sham‐operated controls. When the initial training was given after the surgery, Hx affected the initial and reversal trainings and probe tests. Brain‐derived neurotrophic factor (BDNF) expression, cell numbers and long‐term potentiation (LTP) were examined in the hippocampus on the 10th day, and BrdU and doublecortin staining on the 14th day, after the surgery. Hx decreased the hippocampal BDNF and cells in the CA1/CA3 regions and impaired LTP. BrdU and doublecortin staining was decreased in the dentate gyrus of Hx rats. Results suggest that tongue motor loss impairs hippocampus‐dependent cognitive function, and decreased BDNF expression in the hippocampus may be implicated in its underlying molecular mechanism in relation with decreased neurogenesis/proliferation and impaired LTP.
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Affiliation(s)
- Doyun Kim
- Department of Oral and Maxillofacial Surgery, Dental Research Institute, Seoul National University, School of Dentistry, Seoul, Korea.,Department of Brain Science, Daegu Gyeongbuk Institute of Science & Technology, Dae Gu, Korea
| | - Sena Chung
- Department of Oral and Maxillofacial Surgery, Dental Research Institute, Seoul National University, School of Dentistry, Seoul, Korea
| | - Seung-Hyun Lee
- Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Korea
| | - Se-Young Choi
- Department of Physiology, Dental Research Institute, Seoul National University School of Dentistry, Seoul, Korea
| | - Soung-Min Kim
- Department of Oral and Maxillofacial Surgery, Dental Research Institute, Seoul National University, School of Dentistry, Seoul, Korea
| | - JaeHyung Koo
- Department of Brain Science, Daegu Gyeongbuk Institute of Science & Technology, Dae Gu, Korea
| | - Jong-Ho Lee
- Department of Oral and Maxillofacial Surgery, Dental Research Institute, Seoul National University, School of Dentistry, Seoul, Korea
| | - Jeong Won Jahng
- Department of Oral and Maxillofacial Surgery, Dental Research Institute, Seoul National University, School of Dentistry, Seoul, Korea
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18
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Kubo KY, Murabayashi C, Kotachi M, Suzuki A, Mori D, Sato Y, Onozuka M, Azuma K, Iinuma M. Tooth loss early in life suppresses neurogenesis and synaptophysin expression in the hippocampus and impairs learning in mice. Arch Oral Biol 2017; 74:21-27. [DOI: 10.1016/j.archoralbio.2016.11.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 11/01/2016] [Accepted: 11/03/2016] [Indexed: 11/25/2022]
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19
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Yaoita F. Animal Models for Elucidation of the Mechanisms of Neuropsychiatric Disorders Induced by Sleep and Dietary Habits. YAKUGAKU ZASSHI 2016; 136:895-904. [PMID: 27252067 DOI: 10.1248/yakushi.15-00283] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Numerous changes in human lifestyle in modern life increase the risk of disease. Especially, modern sleep and dietary habits are crucial factors affecting lifestyle disease. In terms of sleep, decreases in total sleep time and in rapid eye movement sleep time have been observed in attention-deficit/hyperactivity disorder (ADHD) patients. From a dietary perspective, mastication during eating has several good effects on systemic, mental, and physical functions of the body. However, few animal experiments have addressed the influence of this decline in sleep duration or of long-term powdered diet feeding on parameters reflecting systemic health. In our studies, we examined both the influence of intermittent sleep deprivation (SD) treatment and long-term powdered diet feeding on emotional behavior in mice, and focused on the mechanisms underlying these impaired behaviors. Our findings were as follows: SD treatment induced hypernoradrenergic and hypodopaminergic states within the frontal cortex. Furthermore, hyperactivity and an explosive number of jumps were observed. Both the hypernoradrenergic state and the jumps were improved by treatment with ADHD therapeutic drugs. On the other hand, long-term powdered diet feeding increased social interaction behaviors. The feeding affected the dopaminergic function of the frontal cortex. In addition, the long-term powdered diet fed mice presented systemic illness signs, such as elevations of blood glucose, and hypertension. This review, describing the SD mice and long-term powdered diet fed mice can be a useful model for elucidation of the mechanism of neuropsychiatric disorders or the discovery of new therapeutic targets in combatting effects of the modern lifestyle.
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Affiliation(s)
- Fukie Yaoita
- Department of Pharmacology, Faculty of Pharmaceutical Science, Tohoku Medical and Pharmaceutical University
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20
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Chronic Powder Diet After Weaning Induces Sleep, Behavioral, Neuroanatomical, and Neurophysiological Changes in Mice. PLoS One 2015; 10:e0143909. [PMID: 26630494 PMCID: PMC4668096 DOI: 10.1371/journal.pone.0143909] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 11/11/2015] [Indexed: 12/23/2022] Open
Abstract
The purpose of this study is to clarify the effects of chronic powder diet feeding on sleep patterns and other physiological/anatomical changes in mice. C57BL/6 male mice were divided into two groups from weaning: a group fed with solid food (SD) and a group fed with powder food (PD), and sleep and physiological and anatomical changes were compared between the groups. PD exhibited less cranial bone structure development and a significant weight gain. Furthermore, these PD mice showed reduced number of neurogenesis in the hippocampus. Sleep analysis showed that PD induced attenuated diurnal sleep/wake rhythm, characterized by increased sleep during active period and decreased sleep during rest period. With food deprivation (FD), PD showed less enhancement of wake/locomotor activity compared to SD, indicating reduced food-seeking behavior during FD. These results suggest that powder feeding in mice results in a cluster of detrimental symptoms caused by abnormal energy metabolism and anatomical/neurological changes.
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Xu X, Cao B, Wang J, Yu T, Li Y. Decision-making deficits associated with disrupted synchronization between basolateral amygdala and anterior cingulate cortex in rats after tooth loss. Prog Neuropsychopharmacol Biol Psychiatry 2015; 60:26-35. [PMID: 25684327 DOI: 10.1016/j.pnpbp.2015.02.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Accepted: 02/05/2015] [Indexed: 12/09/2022]
Abstract
Human studies have shown that multiple teeth loss was significantly associated with cognitive impairment, dementia and Alzheimer's disease. However, the causal relationship between tooth loss and cognitive deficits has not been clarified. Rodents demonstrate human-like cognitive faculties. In this study by performing rat gambling task (RGT), we reported that prolonged tooth loss condition by extracting all left molars in the rats led to an increase in the proportion of poor decision-makers, and decrease in the proportion of good decision-makers compared with controls. No influence was detected on the general activity and motivation after tooth loss. Recent experiments have shown that decision-making performances in the RGT rely on the functional integrity of the amygdala and anterior cingulate cortex (ACC). The theta band brain oscillation has been acknowledged for extensive cognitive functions. Here, we performed multiple-electrode array recordings of local field potential (LFP) in anesthetized rats. The results exhibited an increase in accumulative power of the theta frequency of LFP in the basolateral amygdala (BLA) and decrease of theta power in the ACC in tooth loss rats. Furthermore, cross-correlation analysis displayed that tooth loss suppressed the synchronization of theta frequency of LFP between the BLA and ACC, indicating reduced neuronal communications between these two regions. In conclusion, we demonstrate for the first time that tooth loss leads to higher-order cognitive deficits accompanied by the alteration of theta frequency of LFP in brain circuitries and disruption of neural network integrity.
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Affiliation(s)
- Xiaoxiang Xu
- Department of Biomedical Science, City University of Hong Kong, Hong Kong, China; Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong, China
| | - Bing Cao
- Department of Biomedical Science, City University of Hong Kong, Hong Kong, China; Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong, China
| | - Jun Wang
- Department of Biomedical Science, City University of Hong Kong, Hong Kong, China; Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong, China
| | - Tianran Yu
- Department of Biomedical Science, City University of Hong Kong, Hong Kong, China; Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong, China
| | - Ying Li
- Department of Biomedical Science, City University of Hong Kong, Hong Kong, China; Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong, China.
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Chewing prevents stress-induced hippocampal LTD formation and anxiety-related behaviors: a possible role of the dopaminergic system. BIOMED RESEARCH INTERNATIONAL 2015; 2015:294068. [PMID: 26075223 PMCID: PMC4449872 DOI: 10.1155/2015/294068] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2014] [Accepted: 01/13/2015] [Indexed: 11/17/2022]
Abstract
The present study examined the effects of chewing on stress-induced long-term depression (LTD) and anxiogenic behavior. Experiments were performed in adult male rats under three conditions: restraint stress condition, voluntary chewing condition during stress, and control condition without any treatments except handling. Chewing ameliorated LTD development in the hippocampal CA1 region. It also counteracted the stress-suppressed number of entries to the center region of the open field when they were tested immediately, 30 min, or 60 min after restraint. At the latter two poststress time periods, chewing during restraint significantly increased the number of times of open arm entries in the elevated plus maze, when compared with those without chewing. The in vivo microdialysis further revealed that extracellular dopamine concentration in the ventral hippocampus, which is involved in anxiety-related behavior, was significantly greater in chewing rats than in those without chewing from 30 to 105 min after stress exposure. Development of LTD and anxiolytic effects ameliorated by chewing were counteracted by administering the D1 dopamine receptor antagonist SCH23390, which suggested that chewing may activate the dopaminergic system in the ventral hippocampus to suppress stress-induced anxiogenic behavior.
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23
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How masticatory function and periodontal disease relate to senile dementia. JAPANESE DENTAL SCIENCE REVIEW 2015. [DOI: 10.1016/j.jdsr.2014.09.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
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Oue H, Miyamoto Y, Koretake K, Okada S, Doi K, Jung CG, Michikawa M, Akagawa Y. Tooth loss might not alter molecular pathogenesis in an aged transgenic Alzheimer's disease model mouse. Gerodontology 2014; 33:308-14. [DOI: 10.1111/ger.12153] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/15/2014] [Indexed: 11/29/2022]
Affiliation(s)
- Hiroshi Oue
- Department of Advanced Prosthodontics; Hiroshima University Graduate School of Biomedical & Health Sciences; Hiroshima Japan
| | - Yasunari Miyamoto
- Department of Advanced Prosthodontics; Hiroshima University Graduate School of Biomedical & Health Sciences; Hiroshima Japan
| | - Katsunori Koretake
- Department of Advanced Prosthodontics; Hiroshima University Graduate School of Biomedical & Health Sciences; Hiroshima Japan
| | - Shinsuke Okada
- Department of Advanced Prosthodontics; Hiroshima University Graduate School of Biomedical & Health Sciences; Hiroshima Japan
| | - Kazuya Doi
- Department of Advanced Prosthodontics; Hiroshima University Graduate School of Biomedical & Health Sciences; Hiroshima Japan
| | - Cha-Gyun Jung
- Department of Neurophysiology and Brain Science; Nagoya City University Graduate School of Medical Sciences; Nagoya Japan
| | - Makoto Michikawa
- Department of Biochemistry; Nagoya City University Graduate School of Medical Sciences; Nagoya Japan
| | - Yasumasa Akagawa
- Department of Prosthetic Dentistry; Ohu University School of Dentistry; Koriyama Japan
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25
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Okihara H, Ito JI, Kokai S, Ishida T, Hiranuma M, Kato C, Yabushita T, Ishida K, Ono T, Michikawa M. Liquid diet induces memory impairment accompanied by a decreased number of hippocampal neurons in mice. J Neurosci Res 2014; 92:1010-7. [PMID: 24687840 DOI: 10.1002/jnr.23383] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 02/19/2014] [Accepted: 02/19/2014] [Indexed: 12/16/2022]
Abstract
It is suggested that masticatory dysfunction affects the central nervous system; however, the underlying mechanism remains unknown. Brain-derived neurotrophic factor (BDNF) and its receptor, TrkB, are known to play important roles in memory and learning. In this study, we examined the effects of mastication on memory, the expression levels of BDNF and TrkB, and the number of neurons in the hippocampus of mice. Male C57 BL/6J mice (3 weeks old) were randomly divided into the control group (N = 7) fed chow pellets and the experimental group (N = 7) fed a liquid diet, which reduces mastication during eating. At 14 weeks of age, we performed a passive avoidance test and found that memory and learning ability were impaired in the experimental group compared with the control group. After the behavioral experiment, brains were harvested and analyzed morphologically and biochemically. In the hippocampus of the experimental group, the expression levels of BDNF were significantly higher, whereas those of TrkB were lower than those of the control group. In the cerebral cortex, these levels remained unchanged between the two groups. The ratio of phospho-p44/42 ERK/pan ERK, a downstream molecule of BDNF/TrkB signaling, in the experimental group was significantly lower than that of the control group in the cortex and hippocampus. The number of pyramidal neurons in the hippocampus was lower in the experimental group than in the control group. These findings suggest that reduced mastication induced by a liquid diet in early childhood may impair memory and learning ability, accompanied by neuronal loss in the hippocampus.
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Affiliation(s)
- Hidemasa Okihara
- Department of Biochemistry, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan; Department of Orthodontic Science, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
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Kawahata M, Ono Y, Ohno A, Kawamoto S, Kimoto K, Onozuka M. Loss of molars early in life develops behavioral lateralization and impairs hippocampus-dependent recognition memory. BMC Neurosci 2014; 15:4. [PMID: 24387332 PMCID: PMC3890624 DOI: 10.1186/1471-2202-15-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 01/03/2014] [Indexed: 01/21/2023] Open
Abstract
Background Using senescence-accelerated mouse prone 8 (SAMP8), we examined whether reduced mastication from a young age affects hippocampal-dependent cognitive function. We anesthetized male SAMP8 mice at 8 weeks of age and extracted all maxillary molar teeth of half the animals. The other animals were treated similarly, except that molar teeth were not extracted. At 12 and 24 weeks of age, their general behavior and their ability to recognize novel objects were tested using the open-field test (OFT) and the object-recognition test (ORT), respectively. Results The body weight of molarless mice was reduced significantly compared to that of molar-intact mice after the extraction and did not recover to the weight of age-matched molar-intact mice throughout the experimental period. At 12 weeks of age, molarless mice showed significantly greater locomotor activity in the OFT than molar-intact mice. However, the ability of molarless mice to discriminate a novel object in the ORT was impaired compared to that of molar-intact mice. The ability of both molarless and molar-intact SAMP8 mice to recognize objects was impaired at 24 weeks of age. These results suggest that molarless SAMP8 mice develop a deficit of cognitive function earlier than molar-intact SAMP8 mice. Interestingly, both at 12 and 24 weeks of age, molarless mice showed a lateralized preference of object location in the encoding session of the ORT, in which two identical objects were presented. Their lateralized preference of object location was positively correlated with the rightward turning-direction preference, which reached statistical significance at 24 weeks of age. Conclusions Loss of masticatory function in early life causes malnutrition and chronic stress and impairs the ability to recognize novel objects. Hyperactivation and lateralized rotational behavior are commonly observed with dysfunction of the dopaminergic system, therefore, reduced masticatory function may deplete the mesolimbic and mesocorticolimbic dopaminergic systems to impair the cognitive functions of selective attention and recognition memory in the prefrontal cortex and the hippocampus.
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Affiliation(s)
| | - Yumie Ono
- Department of Prosthodontics & Oral Rehabilitation, Graduate School of Dentistry, Kanagawa Dental University, Yokosuka, Japan.
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Teixeira FB, Pereira Fernandes LDM, Noronha PAT, dos Santos MAR, Gomes-Leal W, Ferraz Maia CDS, Lima RR. Masticatory deficiency as a risk factor for cognitive dysfunction. Int J Med Sci 2014; 11:209-14. [PMID: 24465167 PMCID: PMC3894406 DOI: 10.7150/ijms.6801] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 11/25/2013] [Indexed: 11/13/2022] Open
Abstract
Several studies have demonstrated that chewing helps to maintain cognitive functions in brain regions including the hippocampus, a central nervous system (CNS) region vital for memory and learning. Epidemiological studies suggest that masticatory deficiency is associated with development of dementia, which is related to spatial memory deficits especially in older animals. The purpose of this paper is to review recent work on the effects of masticatory impairment on cognitive functions both in experimental animals and humans. We show that several mechanisms may be involved in the cognitive deficits associated with masticatory deficiency. The epidemiological data suggest a positive correlation between masticatory deficit and Alzheimer's disease. It may be concluded that chewing has important implications for the mechanisms underlying certain cognitive abilities.
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Affiliation(s)
- Francisco Bruno Teixeira
- 1. Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, 66075-900, Belém-Pará, Brazil
| | - Luanna de Melo Pereira Fernandes
- 1. Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, 66075-900, Belém-Pará, Brazil; ; 2. Laboratory Pharmacology of Inflammation and Behavior, Institute of Health Sciences, Federal University of Pará, 66075-900, Belém-Pará, Brazil
| | - Patrycy Assis Tavares Noronha
- 3. Laboratory of Experimental Neuroprotection and Neuroregeneration, Institute of Biological Sciences, Federal University of Pará, 66075-900, Belém-Pará, Brazil
| | - Marcio Antonio Raiol dos Santos
- 1. Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, 66075-900, Belém-Pará, Brazil
| | - Walace Gomes-Leal
- 3. Laboratory of Experimental Neuroprotection and Neuroregeneration, Institute of Biological Sciences, Federal University of Pará, 66075-900, Belém-Pará, Brazil
| | - Cristiane do Socorro Ferraz Maia
- 2. Laboratory Pharmacology of Inflammation and Behavior, Institute of Health Sciences, Federal University of Pará, 66075-900, Belém-Pará, Brazil
| | - Rafael Rodrigues Lima
- 1. Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, 66075-900, Belém-Pará, Brazil
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Oue H, Miyamoto Y, Okada S, Koretake K, Jung CG, Michikawa M, Akagawa Y. Tooth loss induces memory impairment and neuronal cell loss in APP transgenic mice. Behav Brain Res 2013; 252:318-25. [DOI: 10.1016/j.bbr.2013.06.015] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Revised: 06/05/2013] [Accepted: 06/06/2013] [Indexed: 02/08/2023]
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Niijima-Yaoita F, Tsuchiya M, Saito H, Nagasawa Y, Murai S, Arai Y, Nakagawasai O, Nemoto W, Tadano T, Tan-No K. Influence of a long-term powdered diet on the social interaction test and dopaminergic systems in mice. Neurochem Int 2013; 63:309-15. [PMID: 23871718 DOI: 10.1016/j.neuint.2013.07.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2012] [Revised: 06/22/2013] [Accepted: 07/07/2013] [Indexed: 10/26/2022]
Abstract
It is well known that the characteristics of mastication are important for the maintenance of our physical well-being. In this study, to assess the importance of the effects of food hardness during mastication, we investigated whether a long-term powdered diet might cause changes in emotional behavior tests, including spontaneous locomotor activity and social interaction (SI) tests, and the dopaminergic system of the frontal cortex and hippocampus in mice. Mice fed a powdered diet for 17 weeks from weaning were compared with mice fed a standard diet (control). The dopamine turnover and expression of dopamine receptors mRNA in the frontal cortex were also evaluated. Spontaneous locomotor activity, SI time and dopamine turnover of the frontal cortex were increased in powdered diet-fed mice. On the other hand, the expression of dopamine-4 (D4) receptors mRNA in the frontal cortex was decreased in powdered diet-fed mice. Moreover, we examined the effect of PD168077, a selective D4 agonist, on the increased SI time in powdered diet-fed mice. Treatment with PD168077 decreased the SI time. These results suggest that the masticatory dysfunction induced by long-term powdered diet feeding may cause the increased SI time and the changes in the dopaminergic system, especially dopamine D4 receptor subtype in the frontal cortex.
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Affiliation(s)
- Fukie Niijima-Yaoita
- Department of Pharmacology, Tohoku Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai 981-8558, Japan.
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Mendes FDCCDS, de Almeida MNF, Felício APG, Fadel AC, Silva DDJ, Borralho TG, da Silva RP, Bento-Torres J, Vasconcelos PFDC, Perry VH, Ramos EMLS, Picanço-Diniz CW, Sosthenes MCK. Enriched environment and masticatory activity rehabilitation recover spatial memory decline in aged mice. BMC Neurosci 2013; 14:63. [PMID: 23805920 PMCID: PMC3706212 DOI: 10.1186/1471-2202-14-63] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 06/20/2013] [Indexed: 11/23/2022] Open
Abstract
Background To measure the impact of masticatory reduction on learning and memory, previous studies have produced experimental masticatory reduction by modified diet or molar removal. Here we induced spatial learning impairment in mice by reducing masticatory activity and then tested the effect of a combination of environmental enrichment and masticatory rehabilitation in recovering spatial learning at adulthood and in later life. For 6 months (6M) or 18 months (18M), we fed three groups of mice from postnatal day 21 respectively with a hard diet (HD) of pellets; pellets followed by a powdered, soft diet (HD/SD, divided into equal periods); or pellets followed by powder, followed by pellets again (HD/SD/HD, divided into equal periods). To mimic sedentary or active lifestyles, half of the animals from each group were raised from weaning in standard cages (impoverished environment; IE) and the other half in enriched cages (enriched environment; EE). To evaluate spatial learning, we used the Morris water maze. Results IE6M-HD/SD mice showed lower learning rates compared with control (IE6M-HD) or masticatory rehabilitated (IE6MHD/SD/HD) animals. Similarly, EE-HD/SD mice independent of age showed lower performance than controls (EE-HD) or rehabilitated mice (EE-HD/SD/HD). However, combined rehabilitation and EE in aged mice improved learning rate up to control levels. Learning rates did not correlate with swim speed. Conclusions Reduction in masticatory activity imposed on mice previously fed a hard diet (HD/SD) impaired spatial learning in the Morris water maze. In adults, masticatory rehabilitation recovered spatial abilities in both sedentary and active mice, and rehabilitation of masticatory activity combined with EE recovered these losses in aged mice.
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Affiliation(s)
- Fabíola de Carvalho Chaves de Siqueira Mendes
- Universidade Federal do Pará/UFPA, Instituto de Ciências Biológicas, Laboratório de Investigações em Neurodegeneração e Infecção, Hospital Universitário João de Barros Barreto, Rua dos Mundurucus, 4487 - Guamá Belém, Pará, Brasil
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Abstract
INTRODUCTION Over the last 8 years, emerging studies bridging the gap between nutrition and mental health have resolutely established that learning and memory abilities as well as mood can be influenced by diet. However, the mechanisms by which diet modulates mental health are still not well understood. Sources of data In this article, a review of the literature was conducted using PubMed to identify studies that provide functional implications of adult hippocampal neurogenesis (AHN) and its modulation by diet. AREAS OF AGREEMENT One of the brain structures associated with learning and memory as well as mood is the hippocampus. Importantly, the hippocampus is one of the two structures in the adult brain where the formation of newborn neurons, or neurogenesis, persists. AREAS OF CONTROVERSY The exact roles of these newborn neurons in learning, memory formation and mood regulation remain elusive. GROWING POINTS Nevertheless, there has been accumulating evidence linking cognition and mood to neurogenesis occurring in the adult hippocampus. Therefore, modulation of AHN by diet emerges as a possible mechanism by which nutrition impacts on mental health. AREAS TIMELY FOR DEVELOPING RESEARCH This area of investigation is new and needs attention because a better understanding of the neurological mechanisms by which nutrition affect mental health may lead to novel dietary approaches for disease prevention, healthier ageing and discovery of new therapeutic targets for mental illnesses.
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Ohno A, Yoshino F, Yoshida A, Hori N, Ono Y, Kimoto K, Onozuka M, Lee MCI. Soft-food diet induces oxidative stress in the rat brain. Neurosci Lett 2012; 508:42-6. [DOI: 10.1016/j.neulet.2011.12.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2011] [Revised: 11/30/2011] [Accepted: 12/12/2011] [Indexed: 10/14/2022]
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Weijenberg R, Scherder E, Lobbezoo F. Mastication for the mind—The relationship between mastication and cognition in ageing and dementia. Neurosci Biobehav Rev 2011; 35:483-97. [DOI: 10.1016/j.neubiorev.2010.06.002] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2009] [Revised: 06/05/2010] [Accepted: 06/08/2010] [Indexed: 01/14/2023]
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Kubo KY, Ichihashi Y, Kurata C, Iinuma M, Mori D, Katayama T, Miyake H, Fujiwara S, Tamura Y. Masticatory function and cognitive function. Okajimas Folia Anat Jpn 2010; 87:135-140. [PMID: 21174943 DOI: 10.2535/ofaj.87.135] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Recent studies have suggest that masticatory (chewing) function is useful for maintaining neurocognitive function in the elderly. For example, a reduced ability to masticate, such as that resulting from toothlessness or soft-diet feeding, causes learning and memory deficits in aged animals and pathologic changes in the hippocampus. In addition, occlusal disharmony impairs hippocampal memory processes via chronic stress, and induces similar hippocampal pathology. Chewing, however, rescues stress-induced suppression of long-term potentiation in the hippocampus and the stress-induced impairment of hippocampal-dependent learning. These findings strongly suggest a link between mastication and neurocognitive function.
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Affiliation(s)
- Kin-Ya Kubo
- Seijoh University Graduate School of Health Care Studies, 2-172 Fukinodai, Tokai, Aichi 476-8588, Japan.
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Ono Y, Yamamoto T, Kubo KY, Onozuka M. Occlusion and brain function: mastication as a prevention of cognitive dysfunction. J Oral Rehabil 2010; 37:624-40. [PMID: 20236235 DOI: 10.1111/j.1365-2842.2010.02079.x] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Research in animals and humans has shown that mastication maintains cognitive function in the hippocampus, a brain area important for learning and memory. Reduced mastication, an epidemiological risk factor for the development of dementia in humans, attenuates spatial memory and causes hippocampal neurons to deteriorate morphologically and functionally, especially in aged animals. Active mastication rescues the stress-attenuated hippocampal memory process in animals and attenuates the perception of stress in humans by suppressing endocrinological and autonomic stress responses. Active mastication further improves the performance of sustained cognitive tasks by increasing the activation of the hippocampus and the prefrontal cortex, the brain regions that are essential for cognitive processing. Abnormal mastication caused by experimental occlusal disharmony in animals produces chronic stress, which in turn suppresses spatial learning ability. The negative correlation between mastication and corticosteroids has raised the hypothesis that the suppression of the hypothalamic-pituitary-adrenal (HPA) axis by masticatory stimulation contributes, in part, to preserving cognitive functions associated with mastication. In the present review, we examine research pertaining to the mastication-induced amelioration of deficits in cognitive function, its possible relationship with the HPA axis, and the neuronal mechanisms that may be involved in this process in the hippocampus.
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Affiliation(s)
- Y Ono
- Department of Physiology and Neuroscience, Kanagawa Dental College, Yokosuka, Japan.
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Stangl D, Thuret S. Impact of diet on adult hippocampal neurogenesis. GENES AND NUTRITION 2009; 4:271-82. [PMID: 19685256 DOI: 10.1007/s12263-009-0134-5] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Accepted: 07/20/2009] [Indexed: 01/09/2023]
Abstract
Research over the last 5 years has firmly established that learning and memory abilities, as well as mood, can be influenced by diet, although the mechanisms by which diet modulates mental health are not well understood. One of the brain structures associated with learning and memory, as well as mood, is the hippocampus. Interestingly, the hippocampus is one of the two structures in the adult brain where the formation of newborn neurons, or neurogenesis, persists. The level of neurogenesis in the adult hippocampus has been linked directly to cognition and mood. Therefore, modulation of adult hippocampal neurogenesis (AHN) by diet emerges as a possible mechanism by which nutrition impacts on mental health. In this study, we give an overview of the mechanisms and functional implications of AHN and summarize recent findings regarding the modulation of AHN by diet.
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Affiliation(s)
- Doris Stangl
- Centre for the Cellular Basis of Behaviour and MRC Centre for Neurodegeneration Research, The James Black Centre, Institute of Psychiatry, King's College London, 125 Coldharbour Lane, London, SE5 9NU, UK
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