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Anderson RC, Alpass FM. Effectiveness of dairy products to protect against cognitive decline in later life: a narrative review. Front Nutr 2024; 11:1366949. [PMID: 38962439 PMCID: PMC11220571 DOI: 10.3389/fnut.2024.1366949] [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: 01/07/2024] [Accepted: 06/03/2024] [Indexed: 07/05/2024] Open
Abstract
As the world's population ages the prevalence of age-related health concerns is increasing, including neurodegeneration disorders such as mild cognitive impairment, vascular dementia and Alzheimer's disease. Diet is a key modifiable risk factor for the development of neurodegeneration, likely due to gut-brain axis interactions related to neuroinflammation. Analyses of dietary patterns identified dairy as being part of a cognitively healthy diet; however, its contribution to cognitive outcomes is difficult to discern. This narrative review evaluates the literature to determine whether there is sufficient evidence that the consumption of dairy products helps to maintain cognitive function in later life. A search using the terms (dairy OR milk OR cheese OR yogurt OR yogurt) AND ("mild cognitive impairment" OR dementia OR "Alzheimer's disease") identified 796 articles. After screening and sorting, 23 observational studies and 6 intervention studies were identified. The results of the observational studies implied that the relationship between total dairy consumption and cognitive outcomes is inverse U-shaped, with moderate consumption (1-2 servings per day) being the most beneficial. The analysis of the intake of different types of dairy products indicated that fermented products, particularly cheese, were most likely responsible for the observed benefits. The experimental studies all used dairy-derived peptides produced during fermentation as the dietary intervention, and the results indicated that these could be an effective treatment for early-stage cognitive impairment. Further experimental studies with whole dairy products, particularly fermented dairy, are needed to determine whether the regular consumption of these foods should be recommended to maximize the likelihood of healthy cognitive aging.
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Affiliation(s)
| | - Fiona M. Alpass
- Health and Ageing Research Team, School of Psychology, Massey University, Palmerston North, New Zealand
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Chang CY, Chang HH, Wu CY, Tsai YT, Lu TH, Chang WH, Hsu CF, Chen PS, Tseng HH. Peripheral inflammation is associated with impaired sadness recognition in euthymic bipolar patients. J Psychiatr Res 2024; 173:333-339. [PMID: 38579478 DOI: 10.1016/j.jpsychires.2024.03.049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 03/06/2024] [Accepted: 03/26/2024] [Indexed: 04/07/2024]
Abstract
BACKGROUND Inflammation impairs cognitive function in healthy individuals and people with psychiatric disorders, such as bipolar disorder (BD). This effect may also impact emotion recognition, a fundamental element of social cognition. Our study aimed to investigate the relationships between pro-inflammatory cytokines and emotion recognition in euthymic BD patients and healthy controls (HCs). METHODS We recruited forty-four euthymic BD patients and forty healthy controls (HCs) and measured their inflammatory markers, including high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), and TNF-α. We applied validated cognitive tasks, the Wisconsin Card-Sorting Test (WCST) and Continuous Performance Test (CPT), and a social cognitive task for emotion recognition, Diagnostic Analyses of Nonverbal Accuracy, Taiwanese Version (DANVA-2-TW). We analyzed the relationships between cytokines and cognition and then explored possible predictive factors of sadness recognition accuracy. RESULTS Regarding pro-inflammatory cytokines, TNF-α was elevated in euthymic BD patients relative to HCs. In euthymic BD patients only, higher TNF-α levels were associated with lower accuracy of sadness recognition. Regression analysis revealed that TNF-α was an independent predictive factor of sadness recognition in patients with euthymic BD when neurocognition was controlled for. CONCLUSIONS We demonstrated that enhanced inflammation, indicated by increased TNF-α, was an independent predictive factor of impaired sadness recognition in BD patients but not in HCs. Our findings suggested a direct influence of TNF-α on sadness recognition and indicated vulnerability to depression in euthymic BD patients with chronic inflammation.
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Affiliation(s)
- Chih-Yu Chang
- Department of Medicine, College of Medicine, National Cheng Kung University, Taiwan
| | - Hui Hua Chang
- Institute of Clinical Pharmacy and Pharmaceutical Sciences, College of Medicine, National Cheng University, Tainan, Taiwan; School of Pharmacy, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Pharmacy, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Pharmacy, National Cheng Kung University Hospital, Dou-Liou Branch, Yunlin, Taiwan
| | - Cheng Ying Wu
- Department of Psychiatry, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Ying Tsung Tsai
- Department of Psychiatry, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Tsung-Hua Lu
- Department of Psychiatry, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Wei Hung Chang
- Department of Psychiatry, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Psychiatry, National Cheng Kung University Hospital, Dou-Liou Branch, Yunlin, Taiwan
| | - Chia-Fen Hsu
- Department of Occupational Therapy, College of Medicine, National Cheng Kung University, Tainan City, Taiwan
| | - Po See Chen
- Department of Psychiatry, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Institute of Behavioral Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Public Health, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Huai-Hsuan Tseng
- Department of Psychiatry, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Institute of Behavioral Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Public Health, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
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3
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Bilal H, McDonald SJ, Stout JC, Harding IH. Associations of inflammatory cytokines and cortisol with nonmotor features of Huntington's disease. Ann Clin Transl Neurol 2024; 11:989-999. [PMID: 38356101 PMCID: PMC11021624 DOI: 10.1002/acn3.52016] [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: 08/08/2023] [Revised: 10/26/2023] [Accepted: 01/25/2024] [Indexed: 02/16/2024] Open
Abstract
OBJECTIVE Huntington's disease (HD) is an inherited neurodegenerative disease involving progressive motor abnormalities, cognitive decline, and psychiatric disturbances. Depression and cognitive difficulties are among the most impactful symptoms of HD, yet the pathogenesis of these symptoms is not fully understood. HD involves low-level chronic inflammation and dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, which are linked to depression and cognitive impairment in non-HD populations. However, previous research on the relationships of these pathologies with depression and cognition in HD is limited and inconsistent. METHODS Fifty-three adults with the HD gene expansion (30 premanifest and 23 manifest) completed measures of depression and cognitive functioning. Forty-eight out of 53 participants provided hair samples for quantification of cortisol, and 34 participants provided blood samples for quantification of peripheral inflammatory cytokines. We examined the associations of four cytokines (interleukin [IL]-6, IL-10, IL-1β, and tumor necrosis factor [TNF]-α) and cortisol levels with depression and cognitive scores. RESULTS In unadjusted models, higher levels of plasma IL-6, IL-10, and TNF-α correlated with higher depression scores, and higher levels of IL-10 and TNF-α correlated with poorer cognitive performance. After controlling for age, sex, and body mass index, only the correlations of IL-10 with depression and cognitive performance remained significant. No correlations were evident with hair cortisol. INTERPRETATIONS Peripheral inflammation is associated with depression symptoms and cognitive impairment in HD. Our findings suggest that interactions between the immune and nervous systems are important in HD, and highlight the potential of chronic inflammation as a therapeutic target in early stages of HD.
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Affiliation(s)
- Hiba Bilal
- School of Psychological Sciences, and Turner Institute for Brain and Mental HealthMonash UniversityClaytonVictoriaAustralia
| | - Stuart J. McDonald
- Department of Neuroscience, Central Clinical SchoolMonash UniversityPrahranVictoriaAustralia
| | - Julie C. Stout
- School of Psychological Sciences, and Turner Institute for Brain and Mental HealthMonash UniversityClaytonVictoriaAustralia
| | - Ian H. Harding
- Department of Neuroscience, Central Clinical SchoolMonash UniversityPrahranVictoriaAustralia
- Monash Biomedical ImagingMonash UniversityClaytonVictoriaAustralia
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4
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Keegan AP, Savage K, Bousman CA, Nolidin K, Cribb L, Pipingas A, Stough C. Interleukin 10 (IL10) promoter region polymorphism is associated with IL10 serum concentrations and processing speed in healthy community-dwelling older adults. Behav Brain Res 2024; 458:114756. [PMID: 37951418 DOI: 10.1016/j.bbr.2023.114756] [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: 10/17/2023] [Revised: 11/07/2023] [Accepted: 11/08/2023] [Indexed: 11/14/2023]
Abstract
Inflammation is repressed by interleukin 10 (IL10), a potent anti-inflammatory cytokine, and unchecked inflammation can have detrimental effects on cognition. In healthy older adults enrolled in the Australian Research Council Longevity Intervention (ARCLI) cohort we explored whether a known functional single nucleotide polymorphism (SNP) in the promoter region of IL10, -1082 G/A (rs1800896), was associated with reaction times on computerized cognitive testing that included elements of processing speed (i.e., reaction time). Participants were aged 60-75 years (240 females, 158 males), free of dementia and psychiatric disorders, and provide a blood sample. Processing speed was measured using the Swinburne University Computerized Cognitive Assessment Battery (SUCCAB), which includes measures of reaction time (in milliseconds, ms) on six tasks. Blood-derived DNA was genotyped for the IL10 rs1800896 SNP and presence of the APOE E4 allele. General linear models for each SUCCAB subtest were fitted, with age, sex, education (years), APOE E4 carrier status, and IL10 genotype as independent variables. Carriers of the IL10 AA genotype had significantly slower reaction times on multiple tests compared to carriers of the minor allele (AG, GG) and lower IL10 serum levels. Although IL10 SNPs have not been detected in Alzheimer's disease genome-wide associated studies, these results support further exploration of IL10 mechanisms as a possible resilience factor.
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Affiliation(s)
| | - Karen Savage
- School of Health Sciences, Swinburne University of Technology, Hawthorn, Victoria, Australia
| | - Chad A Bousman
- Department of Medical Genetics, Psychiatry, Physiology & Pharmacology, University of Calgary, Calgary, AB, Canada
| | - Karen Nolidin
- School of Health Sciences, Swinburne University of Technology, Hawthorn, Victoria, Australia
| | - Lachlan Cribb
- Department of Psychiatry, The University of Melbourne, Parkville, Victoria, Australia
| | - Andrew Pipingas
- School of Health Sciences, Swinburne University of Technology, Hawthorn, Victoria, Australia
| | - Con Stough
- School of Health Sciences, Swinburne University of Technology, Hawthorn, Victoria, Australia
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5
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Aranda S, Jiménez E, Canales-Rodríguez EJ, Verdolini N, Alonso S, Sepúlveda E, Julià A, Marsal S, Bobes J, Sáiz PA, García-Portilla P, Menchón JM, Crespo JM, González-Pinto A, Pérez V, Arango C, Sierra P, Sanjuán J, Pomarol-Clotet E, Vieta E, Vilella E. Processing speed mediates the relationship between DDR1 and psychosocial functioning in euthymic patients with bipolar disorder presenting psychotic symptoms. Mol Psychiatry 2024:10.1038/s41380-024-02480-1. [PMID: 38374360 DOI: 10.1038/s41380-024-02480-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 02/01/2024] [Accepted: 02/05/2024] [Indexed: 02/21/2024]
Abstract
The DDR1 locus is associated with the diagnosis of schizophrenia and with processing speed in patients with schizophrenia and first-episode psychosis. Here, we investigated whether DDR1 variants are associated with bipolar disorder (BD) features. First, we performed a case‒control association study comparing DDR1 variants between patients with BD and healthy controls. Second, we performed linear regression analyses to assess the associations of DDR1 variants with neurocognitive domains and psychosocial functioning. Third, we conducted a mediation analysis to explore whether neurocognitive impairment mediated the association between DDR1 variants and psychosocial functioning in patients with BD. Finally, we studied the association between DDR1 variants and white matter microstructure. We did not find any statistically significant associations in the case‒control association study; however, we found that the combined genotypes rs1264323AA-rs2267641AC/CC were associated with worse neurocognitive performance in patients with BD with psychotic symptoms. In addition, the combined genotypes rs1264323AA-rs2267641AC/CC were associated with worse psychosocial functioning through processing speed. We did not find correlations between white matter microstructure abnormalities and the neurocognitive domains associated with the combined genotypes rs1264323AA-rs2267641AC/CC. Overall, the results suggest that DDR1 may be a marker of worse neurocognitive performance and psychosocial functioning in patients with BD, specifically those with psychotic symptoms.
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Affiliation(s)
- Selena Aranda
- Institut d'Investigació Sanitària Pere Virgili-CERCA, Reus, Spain
- Hospital Universitari Institut Pere Mata, Reus, Spain
- Universitat Rovira i Virgili, Reus, Spain
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain
| | - Esther Jiménez
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain
- Bipolar and Depressive Disorders Unit, Hospital Clinic, Institute of Neurosciences, University of Barcelona, IDIBAPS, Barcelona, Spain
- Department of Psychiatry, University of the Basque Country (UPV-EHU), Vitoria-Gasteiz, Spain
| | - Erick J Canales-Rodríguez
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain
- FIDMAG Germanes Hospitalàries Research Foundation, Sant Boi de Llobregat, Barcelona, Spain
- Signal Processing Laboratory (LTS5), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Norma Verdolini
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain
- Bipolar and Depressive Disorders Unit, Hospital Clinic, Institute of Neurosciences, University of Barcelona, IDIBAPS, Barcelona, Spain
- FIDMAG Germanes Hospitalàries Research Foundation, Sant Boi de Llobregat, Barcelona, Spain
| | - Silvia Alonso
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain
- Bipolar and Depressive Disorders Unit, Hospital Clinic, Institute of Neurosciences, University of Barcelona, IDIBAPS, Barcelona, Spain
| | - Esteban Sepúlveda
- Institut d'Investigació Sanitària Pere Virgili-CERCA, Reus, Spain
- Hospital Universitari Institut Pere Mata, Reus, Spain
- Universitat Rovira i Virgili, Reus, Spain
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain
| | - Antonio Julià
- Rheumatology Research Group, Vall d'Hebron Research Institute, Barcelona, Spain
| | - Sara Marsal
- Rheumatology Research Group, Vall d'Hebron Research Institute, Barcelona, Spain
| | - Julio Bobes
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain
- Department of Psychiatry, Universidad de Oviedo, Oviedo, Spain
- nstituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain
- Instituto Universitario de Neurociencias del Principado de Asturias (INEUROPA), Oviedo, Spain
- Servicio de Salud del Principado de Asturias (SESPA) Oviedo, Oviedo, Spain
| | - Pilar A Sáiz
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain
- Department of Psychiatry, Universidad de Oviedo, Oviedo, Spain
- nstituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain
- Instituto Universitario de Neurociencias del Principado de Asturias (INEUROPA), Oviedo, Spain
- Servicio de Salud del Principado de Asturias (SESPA) Oviedo, Oviedo, Spain
| | - Paz García-Portilla
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain
- Department of Psychiatry, Universidad de Oviedo, Oviedo, Spain
- nstituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain
- Instituto Universitario de Neurociencias del Principado de Asturias (INEUROPA), Oviedo, Spain
- Servicio de Salud del Principado de Asturias (SESPA) Oviedo, Oviedo, Spain
| | - Jose M Menchón
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain
- Bellvitge Biomedical Research Institute-IDIBELL, Bellvitge University Hospital, Barcelona, Spain
- Department of Clinical Sciences, University of Barcelona, Barcelona, Spain
| | - José M Crespo
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain
- Bellvitge Biomedical Research Institute-IDIBELL, Bellvitge University Hospital, Barcelona, Spain
- Department of Clinical Sciences, University of Barcelona, Barcelona, Spain
| | - Ana González-Pinto
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain
- Department of Psychiatry, University of the Basque Country (UPV-EHU), Vitoria-Gasteiz, Spain
- Araba University Hospital, Bioaraba Research Institute, UPV/EHU, Vitoria-Gasteiz, Spain
| | - Víctor Pérez
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain
- Hospital de Mar. Mental Health Institute, Barcelona, Spain
- Neurosciences Research Unit, Hospital del Mar d'Investigacions Mèdiques, Barcelona, Spain
- Department of Experimental and Health Sciences, Pompeu Fabra University, Barcelona, Spain
| | - Celso Arango
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain
- Institute of Psychiatry and Mental Health, Madrid, Spain
- Hospital General Universitario Gregorio Marañón, Madrid, Spain
- Universidad Complutense, Madrid, Spain
| | - Pilar Sierra
- La Fe University and Polytechnic Hospital, Valencia, Spain
- Department of Psychiatry, School of Medicine, University of Valencia, Valencia, Spain
| | - Julio Sanjuán
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain
- Department of Psychiatry, School of Medicine, University of Valencia, Valencia, Spain
| | - Edith Pomarol-Clotet
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain
- FIDMAG Germanes Hospitalàries Research Foundation, Sant Boi de Llobregat, Barcelona, Spain
| | - Eduard Vieta
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain
- Bipolar and Depressive Disorders Unit, Hospital Clinic, Institute of Neurosciences, University of Barcelona, IDIBAPS, Barcelona, Spain
| | - Elisabet Vilella
- Institut d'Investigació Sanitària Pere Virgili-CERCA, Reus, Spain.
- Hospital Universitari Institut Pere Mata, Reus, Spain.
- Universitat Rovira i Virgili, Reus, Spain.
- Centro de Investigación Biomédica en Red en Salud Mental (CIBERSAM)-Instituto de Salud Carlos III, Madrid, Spain.
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Dyer AH, McNulty H, Caffrey A, Gordon S, Laird E, Hoey L, Hughes CF, Ward M, Strain JJ, O'Kane M, Tracey F, Molloy AM, Cunningham C, McCarroll K. Low-Grade systemic inflammation is associated with domain-specific cognitive performance and cognitive decline in older adults: Data from the TUDA study. Neurobiol Aging 2024; 134:94-105. [PMID: 38043161 DOI: 10.1016/j.neurobiolaging.2023.11.008] [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: 08/11/2023] [Revised: 11/12/2023] [Accepted: 11/21/2023] [Indexed: 12/05/2023]
Abstract
Studies examining the relationships between chronic inflammation, cognitive function and cognitive decline in older adults have yielded conflicting results. In a large cohort of older adults free from established dementia (n = 3270; 73.1 ± 7.9 years; 68.4% female), we evaluated the cross-sectional and longitudinal relationships between serum cytokines (IL-6, IL-10, TNF-α) and both global and domain-specific cognitive performance (Repeatable Battery for Assessment of Neuropsychological Status [RBANS]). Higher IL-6 (OR: 1.33; 1.06, 1.66, p = 0.01), TNF-α (OR: 1.35; 1.09, 1.67, p = 0.01) and IL-6:IL-10 Ratio (OR: 1.43; 1.17, 1.74, p = 0.001) were cross-sectionally associated with impaired global RBANS performance. For specific cognitive domains, greatest effect sizes were observed between higher TNF-α levels and poorer visual-spatial and attention performance. In a subset of participants (n = 725; 69.8 ± 5.5 years; 67.0% female) with repeat assessment performed at a median of 5.4 years, only higher baseline IL-6:IL-10 ratio was associated with impaired incident overall, immediate memory and visual-spatial performance. Associations were stronger in females, but not modified by age or APOE genotype.
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Affiliation(s)
- Adam H Dyer
- Department of Age-Related Healthcare, Tallaght University Hospital, United Kingdom; Department of Medical Gerontology, School of Medicine, Trinity College Dublin, United Kingdom.
| | - Helene McNulty
- The Nutrition Innovation Centre for Food and Health, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland, United Kingdom
| | - Aoife Caffrey
- The Nutrition Innovation Centre for Food and Health, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland, United Kingdom
| | - Shane Gordon
- The Nutrition Innovation Centre for Food and Health, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland, United Kingdom
| | - Eamon Laird
- Department of Physical Education and Sport Science, University of Limerick, United Kingdom
| | - Leane Hoey
- The Nutrition Innovation Centre for Food and Health, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland, United Kingdom
| | - Catherine F Hughes
- The Nutrition Innovation Centre for Food and Health, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland, United Kingdom
| | - Mary Ward
- The Nutrition Innovation Centre for Food and Health, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland, United Kingdom
| | - J J Strain
- The Nutrition Innovation Centre for Food and Health, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland, United Kingdom
| | - Maurice O'Kane
- Clinical Chemistry Laboratory, Altnagelvin Hospital, Western Health and Social Care Trust, Londonderry, Northern Ireland, United Kingdom
| | - Fergal Tracey
- Causeway Hospital, Northern Health and Social Care Trust, Coleraine, Northern Ireland, United Kingdom
| | | | - Conal Cunningham
- Department of Medical Gerontology, School of Medicine, Trinity College Dublin, United Kingdom; Mercer's Institute for Successful Ageing, St James's Hospital, Dublin, Ireland
| | - Kevin McCarroll
- Department of Medical Gerontology, School of Medicine, Trinity College Dublin, United Kingdom; Mercer's Institute for Successful Ageing, St James's Hospital, Dublin, Ireland
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7
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Li X, Ma L. From biological aging to functional decline: Insights into chronic inflammation and intrinsic capacity. Ageing Res Rev 2024; 93:102175. [PMID: 38145874 DOI: 10.1016/j.arr.2023.102175] [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: 05/18/2023] [Revised: 12/06/2023] [Accepted: 12/19/2023] [Indexed: 12/27/2023]
Abstract
Intrinsic capacity is the sum of an individual's physical and mental capacities, which helps determine functional ability. Intrinsic capacity decline is an important predictor of adverse health outcomes and can identify individuals at higher risk of functional decline. Aging is characterized by a decrease in physiological reserves and functional abilities. Chronic inflammation, a mechanism of aging, is associated with decreased intrinsic capacity, which may mirror the broader relationship between aging and functional ability. Therefore, it is crucial for maintaining functional ability and promoting healthy aging to study the mechanisms of intrinsic capacity decline, identify easily available markers, and make targets for intervention from the perspective of chronic inflammation. We reviewed the current research on chronic inflammation, inflammation-related markers, and intrinsic capacity. To date, there is still no inflammatory markers with high specificity and sensitivity to monitor intrinsic capacity decline. Interleukin-6, C-reactive protein, and tumor necrosis factor-alpha may potentially indicate changes in intrinsic capacity, but their results with intrinsic capacity or each intrinsic capacity domain are inconsistent. Considering the variations in individual responses to changes in inflammatory markers, it may be beneficial to explore the use of multiple analytes instead of relying on a single marker. This approach could be valuable in monitoring the decline of intrinsic capacity in the future.
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Affiliation(s)
- Xiaxia Li
- Department of Geriatrics, Xuanwu Hospital, Capital Medical University, National Clinical Research Center for Geriatric Disorders, Beijing, China
| | - Lina Ma
- Department of Geriatrics, Xuanwu Hospital, Capital Medical University, National Clinical Research Center for Geriatric Disorders, Beijing, China.
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Bousquet A, Sanderson K, O’Shea TM, Fry RC. Accelerated Aging and the Life Course of Individuals Born Preterm. CHILDREN (BASEL, SWITZERLAND) 2023; 10:1683. [PMID: 37892346 PMCID: PMC10605448 DOI: 10.3390/children10101683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Revised: 09/29/2023] [Accepted: 10/11/2023] [Indexed: 10/29/2023]
Abstract
Individuals born preterm have shorter lifespans and elevated rates of chronic illness that contribute to mortality risk when compared to individuals born at term. Emerging evidence suggests that individuals born preterm or of low birthweight also exhibit physiologic and cellular biomarkers of accelerated aging. It is unclear whether, and to what extent, accelerated aging contributes to a higher risk of chronic illness and mortality among individuals born preterm. Here, we review accelerated aging phenotypes in adults born preterm and biological pathways that appear to contribute to accelerated aging. We highlight biomarkers of accelerated aging and various resiliency factors, including both pharmacologic and non-pharmacologic factors, that might buffer the propensity for accelerated aging among individuals born preterm.
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Affiliation(s)
- Audrey Bousquet
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599, USA; (A.B.); (R.C.F.)
| | - Keia Sanderson
- Department of Internal Medicine, School of Medicine, University of North Carolina, Chapel Hill, NC 27599, USA;
| | - T. Michael O’Shea
- Department of Pediatrics, School of Medicine, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Rebecca C. Fry
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599, USA; (A.B.); (R.C.F.)
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Capogna E, Watne LO, Sørensen Ø, Guichelaar CJ, Idland AV, Halaas NB, Blennow K, Zetterberg H, Walhovd KB, Fjell AM, Vidal-Piñeiro D. Associations of neuroinflammatory IL-6 and IL-8 with brain atrophy, memory decline, and core AD biomarkers - in cognitively unimpaired older adults. Brain Behav Immun 2023; 113:56-65. [PMID: 37400002 DOI: 10.1016/j.bbi.2023.06.027] [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: 02/21/2023] [Revised: 05/31/2023] [Accepted: 06/27/2023] [Indexed: 07/05/2023] Open
Abstract
Concentrations of pro-inflammatory cytokines -interleukin-6 (IL-6) and interleukin-8 (IL-8) - are increased with age and in Alzheimer's disease (AD). It is not clear whether concentrations of IL-6 and IL-8 in the central nervous system predict later brain and cognitive changes over time nor whether this relationship is mediated by core AD biomarkers. Here, 219 cognitively healthy older adults (62-91 years), with baseline cerebrospinal fluid (CSF) measures of IL-6 and IL-8 were followed over time - up to 9 years - with assessments that included cognitive function, structural magnetic resonance imaging, and CSF measurements of phosphorylated tau (p-tau) and amyloid-β (Aβ-42) concentrations (for a subsample). Higher baseline CSF IL-8 was associated with better memory performance over time in the context of lower levels of CSF p-tau and p-tau/Aβ-42 ratio. Higher CSF IL-6 was related to less CSF p-tau changes over time. The results are in line with the hypothesis suggesting that an up-regulation of IL-6 and IL-8 in the brain may play a neuroprotective role in cognitively healthy older adults with lower load of AD pathology.
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Affiliation(s)
- Elettra Capogna
- Centre for Lifespan Changes in Brain and Cognition, Department of Psychology, University of Oslo, 0373 Oslo, Norway.
| | - Leiv Otto Watne
- Department of Geriatric Medicine, Akershus University Hospital, Lørenskog, Norway; Institute of Clinical Medicine, University of Oslo, Campus Ahus, Oslo, Norway
| | - Øystein Sørensen
- Centre for Lifespan Changes in Brain and Cognition, Department of Psychology, University of Oslo, 0373 Oslo, Norway
| | - Carlijn Jamila Guichelaar
- Centre for Lifespan Changes in Brain and Cognition, Department of Psychology, University of Oslo, 0373 Oslo, Norway
| | - Ane Victoria Idland
- Oslo Delirium Research Group, Department of Geriatric Medicine, Oslo University Hospital, Oslo, Norway
| | - Nathalie Bodd Halaas
- Oslo Delirium Research Group, Department of Geriatric Medicine, Oslo University Hospital, Oslo, Norway
| | - Kaj Blennow
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Mölndal, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Henrik Zetterberg
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Mölndal, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden; Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK; UK Dementia Research Institute at UCL, London, UK; Hong Center for Neurodegenerative Diseases, Hong Kong, China; Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Kristine Beate Walhovd
- Centre for Lifespan Changes in Brain and Cognition, Department of Psychology, University of Oslo, 0373 Oslo, Norway; Computational Radiology and Artificial Intelligence, Department of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo, Norway
| | - Anders Martin Fjell
- Centre for Lifespan Changes in Brain and Cognition, Department of Psychology, University of Oslo, 0373 Oslo, Norway; Computational Radiology and Artificial Intelligence, Department of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo, Norway
| | - Didac Vidal-Piñeiro
- Centre for Lifespan Changes in Brain and Cognition, Department of Psychology, University of Oslo, 0373 Oslo, Norway
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10
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Slaney C, Sallis HM, Jones HJ, Dardani C, Tilling K, Munafò MR, Davey Smith G, Mahedy L, Khandaker GM. Association between inflammation and cognition: Triangulation of evidence using a population-based cohort and Mendelian randomization analyses. Brain Behav Immun 2023; 110:30-42. [PMID: 36791891 PMCID: PMC10728829 DOI: 10.1016/j.bbi.2023.02.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 01/23/2023] [Accepted: 02/10/2023] [Indexed: 02/15/2023] Open
Abstract
BACKGROUND Inflammation is associated with cognitive functioning and dementia in older adults, but whether inflammation is related to cognitive functioning in youth and whether these associations are causal remains unclear. METHODS In a population-based cohort (Avon Longitudinal Study of Parents and Children; ALSPAC), we investigated cross-sectional associations of inflammatory markers (C-reactive protein [CRP], Interleukin-6 [IL-6] and Glycoprotein acetyls [GlycA]) with measures of cold (working memory, response inhibition) and hot (emotion recognition) cognition at age 24 (N = 3,305 in multiple imputation models). Furthermore, we conducted one-sample and two-sample bidirectional Mendelian randomization (MR) analyses to examine potential causal effects of genetically-proxied inflammatory markers (CRP, GlycA, IL-6, IL-6 receptor, soluble IL-6 receptor) on cognitive measures (above) and on general cognitive ability. RESULTS In the ALSPAC cohort, there was limited evidence of an association between standardised inflammatory markers and standardised cognitive measures at age 24 after adjusting for potential confounders (N = 3,305; beta range, -0.02 [95 % confidence interval (CI) -0.06 to 0.02, p = 0.27] to 0.02 [95 % CI -0.02 to 0.05, p = 0.33]). Similarly, we found limited evidence of potential effects of 1-unit increase in genetically-proxied inflammatory markers on standardised working memory, emotion recognition or response inhibition in one-sample MR using ALSPAC data (beta range, -0.73 [95 % CI -2.47 to 1.01, p = 0.41] to 0.21 [95 % CI -1.42 to 1.84, p = 0.80]; or on standardised general cognitive ability in two-sample MR using the latest Genome-Wide Association Study (GWAS) datasets (inverse-variance weighted beta range, -0.02 [95 % CI -0.05 to 0.01, p = 0.12] to 0.03 [95 % CI -0.01 to 0.07, p = 0.19]). CONCLUSIONS Our MR findings do not provide strong evidence of a potential causal effect of inflammatory markers (CRP, IL-6, IL-6 receptor, GlycA) on the cognitive functions examined here. Given the large confidence intervals in the one-sample MR, larger GWAS of specific cognitive measures are needed to enable well-powered MR analyses to investigate whether inflammation causally influences specific cognitive domains.
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Affiliation(s)
- Chloe Slaney
- MRC Integrative Epidemiology Unit at the University of Bristol, UK; School of Psychological Science, University of Bristol, 12a Priory Road, Bristol, UK; Centre for Academic Mental Health, Population Health Sciences, Bristol Medical School, University of Bristol, UK.
| | - Hannah M Sallis
- MRC Integrative Epidemiology Unit at the University of Bristol, UK; School of Psychological Science, University of Bristol, 12a Priory Road, Bristol, UK; Centre for Academic Mental Health, Population Health Sciences, Bristol Medical School, University of Bristol, UK; Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Hannah J Jones
- MRC Integrative Epidemiology Unit at the University of Bristol, UK; Centre for Academic Mental Health, Population Health Sciences, Bristol Medical School, University of Bristol, UK; National Institute for Health Research Biomedical Research Centre at the University Hospitals Bristol NHS Foundation Trust and the University of Bristol, UK
| | - Christina Dardani
- Centre for Academic Mental Health, Population Health Sciences, Bristol Medical School, University of Bristol, UK; Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Kate Tilling
- MRC Integrative Epidemiology Unit at the University of Bristol, UK; Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Marcus R Munafò
- MRC Integrative Epidemiology Unit at the University of Bristol, UK; School of Psychological Science, University of Bristol, 12a Priory Road, Bristol, UK; National Institute for Health Research Biomedical Research Centre at the University Hospitals Bristol NHS Foundation Trust and the University of Bristol, UK
| | - George Davey Smith
- MRC Integrative Epidemiology Unit at the University of Bristol, UK; Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK; National Institute for Health Research Biomedical Research Centre at the University Hospitals Bristol NHS Foundation Trust and the University of Bristol, UK
| | - Liam Mahedy
- MRC Integrative Epidemiology Unit at the University of Bristol, UK; Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK; National Institute for Health Research Biomedical Research Centre at the University Hospitals Bristol NHS Foundation Trust and the University of Bristol, UK
| | - Golam M Khandaker
- MRC Integrative Epidemiology Unit at the University of Bristol, UK; Centre for Academic Mental Health, Population Health Sciences, Bristol Medical School, University of Bristol, UK; Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK; National Institute for Health Research Biomedical Research Centre at the University Hospitals Bristol NHS Foundation Trust and the University of Bristol, UK
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11
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Feng L, Wang Y, Zeng D, Wang M, Duan X. Predictors of cognitive decline in older individuals without dementia: An updated meta-analysis. Ann Clin Transl Neurol 2023; 10:497-506. [PMID: 36705073 PMCID: PMC10109353 DOI: 10.1002/acn3.51740] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 01/12/2023] [Accepted: 01/14/2023] [Indexed: 01/28/2023] Open
Abstract
OBJECTIVE To evaluate the effect of overall peripheral inflammatory levels on cognitive function, we explored the relationship between established biomarkers of peripheral inflammation (circulating C-reactive protein [CRP], interleukin-6 [IL-6], and tumor necrosis factor-α [TNF-α]) and cognitive decline by performing a review of observational studies and creating an updated summary. METHODS We included literatures exploring the relationship between peripheral levels of CRP, IL-6, and TNF-α and subsequent cognitive decline, published until July 2022, by searching the following databases: PubMed, Embase, Web of Science, the Cochrane Library, ClinicalTrials, CNKI, and VIP databases. We used random-effects models to pool the odds ratios (ORs) for the risks of subsequent cognitive decline in older adults with high levels of peripheral inflammation. We initially screened out 501 literatures, of which only 17 were ultimately eligible. Overall, there were 19,516 older individuals included in our meta-analysis, and 2134 of them experienced subsequent cognitive change. RESULTS Individuals with high levels of peripheral inflammation may have 14% more chance to develop subsequent cognitive decline than those with low levels (OR = 1.14, 95% CI: 1.03-1.27; p < 0.00001). In the subgroup analysis, the incidence of cognitive decline was higher in individuals with high levels of IL-6. This study further demonstrates the link between systemic inflammation and cognitive status. INTERPRETATION Detecting CRP, IL-6, and TNF-α in peripheral blood is necessary, as they may become effective indicators for forthcoming cognitive performance.
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Affiliation(s)
- Lan Feng
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, China.,Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, China.,Department of Anesthesiology, Southwest Medical University, Luzhou, China
| | - Yuhao Wang
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, China.,Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, China.,Department of Anesthesiology, Southwest Medical University, Luzhou, China
| | - Daojun Zeng
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, China.,Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, China.,Department of Anesthesiology, Southwest Medical University, Luzhou, China
| | - Maohua Wang
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, China.,Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, China.,Department of Anesthesiology, Southwest Medical University, Luzhou, China
| | - Xiaoxia Duan
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, China.,Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, China.,Department of Anesthesiology, Southwest Medical University, Luzhou, China
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12
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Zhuo B, Zheng D, Cai M, Wang C, Zhang S, Zhang Z, Tian F, Wang X, Lin H. Mediation Effect of Brain Volume on the Relationship Between Peripheral Inflammation and Cognitive Decline. J Alzheimers Dis 2023; 95:523-533. [PMID: 37545239 DOI: 10.3233/jad-230253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
BACKGROUND Studies have reported the associations between inflammation, brain volume, and cognition separately. It is reasonable to assume peripheral inflammation may contribute to cognitive decline through brain volume atrophy. OBJECTIVE To examine the associations between peripheral inflammation, brain volume, and cognition among adults, and to investigate whether brain volume atrophy mediates the inflammation-cognition relationshipMethods:We retrieved 20,381 participants with available data on peripheral inflammation, brain volume, and cognition from the UK Biobank cohort. Cognitive function was assessed by performance on cognitive tasks probing various cognitive domains. Brain volumes were measured by magnetic resonance imaging (MRI). Multivariable linear models were used to investigate the associations between three peripheral inflammatory indexes (C-reactive protein, systemic immune-inflammatory index, neutrophil-to-lymphocyte ratio), brain volume, and cognition. Mediation analyses were conducted to assess the potential mediating effect of brain volume atrophy. All results were corrected for multiple comparisons using the false-discovery rate (FDR). RESULTS Peripheral inflammation was inversely associated with grey matter volume (GMV), white matter volume (WMV), and cognition after adjusting for potential covariates. For instance, CRP was associated with the GMV of left parahippocampal gyrus (β= -0.05, 95% confidence interval [CI]: -0.06 to -0.04, pFDR =1.07×10-16) and general cognitive factor (β= -0.03, 95% CI: -0. -0.04 to -0.01, pFDR = 0.001). Brain volume atrophy mediated the inflammation-cognitive decline relationship, accounting for 15-29% of the overall impact. CONCLUSION In this cohort study, peripheral inflammation was associated with brain volume atrophy and cognitive decline. Brain atrophy may mediate the inflammation-cognitive decline relationship.
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Affiliation(s)
- Bingting Zhuo
- Department of Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Dashan Zheng
- Department of Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Miao Cai
- Department of Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Chongjian Wang
- Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Henan, China
| | - Shiyu Zhang
- Department of Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Zilong Zhang
- Department of Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Fei Tian
- Department of Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Xiaojie Wang
- Department of Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Hualiang Lin
- Department of Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong, China
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13
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Anderson RC. Can probiotics mitigate age-related neuroinflammation leading to improved cognitive outcomes? Front Nutr 2022; 9:1012076. [PMID: 36505245 PMCID: PMC9729724 DOI: 10.3389/fnut.2022.1012076] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 11/07/2022] [Indexed: 11/25/2022] Open
Abstract
Changes in brain structure and cognitive function are a natural part of aging; however, in some cases these changes are more severe resulting in mild cognitive impairment (MCI) or Alzheimer's disease (AD). Evidence is mounting to show that neuroinflammation is an underlying risk factor for neurodegenerative disease progression. Age-related neuroinflammation does not appear to occur in isolation and is part of increased systemic inflammation, which may in turn be triggered by changes in the gut associated with aging. These include an increase in gut permeability, which allows immune triggering compounds into the body, and alterations in gut microbiota composition leading to dysbiosis. It therefore follows that, treatments that can maintain healthy gut function may reduce inflammation and protect against, or improve, symptoms of age-associated neurodegeneration. The aim of this mini review was to evaluate whether probiotics could be used for this purpose. The analysis concluded that there is preliminary evidence to suggest that specific probiotics may improve cognitive function, particularly in those with MCI; however, this is not yet convincing and larger, multilocation, studies focus on the effects of probiotics alone are required. In addition, studies that combine assessment of cognition alongside analysis of inflammatory biomarkers and gut function are needed. Immense gains could be made to the quality of life of the aging population should the hypothesis be proven to be correct.
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